Stockfish 16.1

Official release version of Stockfish 16.1

Bench: 1303971

---

Stockfish 16.1

Today, we have the pleasure to announce Stockfish 16.1. As always, you can
freely download it at https://stockfishchess.org/download and use it in the GUI
of your choice[1].

Don't forget to join our Discord server[2] to get in touch with the community of
developers and users of the project!

*Quality of chess play*

In our testing against its predecessor, Stockfish 16.1 shows a notable
improvement in performance, with an Elo gain of up to 27 points and winning over
2 times more game pairs[3] than it loses.

*Update highlights*

*Improved evaluation*

- Updated neural network architecture: The neural network architecture has
  undergone two updates and is currently in its 8th version[4].
- Removal of handcrafted evaluation (HCE): This release marks the removal of the
  traditional handcrafted evaluation and the transition to a fully neural
  network-based approach[5].
- Dual NNUE: For the first time, Stockfish includes a secondary neural
  network[6], used to quickly evaluate positions that are easily decided.

*UCI Options removed*

`Use NNUE` and `UCI_AnalyseMode`[7] have been removed as they no longer had any
effect. `SlowMover`[8] has also been removed in favor of `Move Overhead`.

*More binaries*

We now offer 13 new binaries. These new binaries include `avx512`, `vnni256`,
`vnni512`, `m1-apple-silicon`, and `armv8-dotprod`, which take advantage of
specific CPU instructions for improved performance.
For most users, using `sse41-popcnt` (formerly `modern`), `avx2`, or `bmi2`
should be enough, but if your CPU supports these new instructions, feel free to
try them!

*Development changes*

- Updated testing book: This new book[9], now derived exclusively from the open
  Lichess database[10], is 10 times larger than its predecessor, and has been
  used to test potential improvements to Stockfish over the past few months.
- Consolidation of repositories: Aiming to simplify access to our resources, we
  have moved most Stockfish-related repositories into the official Stockfish
  organization[11] on GitHub.
- Growing maintainer team: We welcome Disservin[12] to the team of maintainers
  of the project! This extra pair of hands will ensure the lasting success of
  Stockfish.

*Thank you*

The Stockfish project builds on a thriving community of enthusiasts (thanks
everybody!) who contribute their expertise, time, and resources to build a free
and open-source chess engine that is robust, widely available, and very strong.

We would like to express our gratitude for the 10k stars[13] that light up our
GitHub project! Thank you for your support and encouragement – your recognition
means a lot to us.

We invite our chess fans to join the Fishtest testing framework[14], and
programmers to contribute to the project either directly to Stockfish[15] (C++),
to Fishtest[16] (HTML, CSS, JavaScript, and Python), to our trainer
nnue-pytorch[17] (C++ and Python), or to our website[18] (HTML, CSS/SCSS, and
JavaScript).

The Stockfish team

[1] https://github.com/official-stockfish/Stockfish/wiki/Download-and-usage#download-a-chess-gui
[2] https://discord.gg/GWDRS3kU6R
[3] https://tests.stockfishchess.org/tests/view/65d666051d8e83c78bfddbd8
[4] https://github.com/official-stockfish/nnue-pytorch/blob/master/docs/nnue.md#sfnnv8-architecture
[5] https://github.com/official-stockfish/Stockfish/commit/af110e0
[6] https://github.com/official-stockfish/Stockfish/commit/584d9ef
[7] https://github.com/official-stockfish/Stockfish/commit/c53d2ec
[8] https://github.com/official-stockfish/Stockfish/commit/536d692
[9] https://github.com/official-stockfish/books/commit/426eca4
[10] https://database.lichess.org/
[11] https://github.com/official-stockfish/
[12] https://github.com/Disservin
[13] https://github.com/official-stockfish/Stockfish/stargazers
[14] https://github.com/official-stockfish/fishtest/wiki/Running-the-worker
[15] https://github.com/official-stockfish/Stockfish
[16] https://github.com/official-stockfish/fishtest
[17] https://github.com/official-stockfish/nnue-pytorch
[18] https://github.com/official-stockfish/stockfish-web

.clang-format

@@ -0,0 +1,44 @@
+AccessModifierOffset: -1
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: Consecutive
+AlignConsecutiveDeclarations: Consecutive
+AlignEscapedNewlines: DontAlign
+AlignOperands: AlignAfterOperator
+AlignTrailingComments: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortEnumsOnASingleLine: false
+AllowShortIfStatementsOnASingleLine: false
+AlwaysBreakTemplateDeclarations: Yes
+BasedOnStyle: WebKit
+BitFieldColonSpacing: After
+BinPackParameters: false
+BreakBeforeBinaryOperators: NonAssignment
+BreakBeforeBraces: Custom
+BraceWrapping:
+  AfterFunction: false 
+  AfterClass: false
+  AfterControlStatement: true
+  BeforeElse: true
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializers: AfterColon
+BreakStringLiterals: false
+ColumnLimit: 100
+ContinuationIndentWidth: 2
+Cpp11BracedListStyle: true
+IndentGotoLabels: false
+IndentPPDirectives: BeforeHash
+IndentWidth: 4
+MaxEmptyLinesToKeep: 2
+NamespaceIndentation: None
+PackConstructorInitializers: Never
+ReflowComments: false
+SortIncludes: false
+SortUsingDeclarations: false
+SpaceAfterCStyleCast: true
+SpaceAfterTemplateKeyword: false
+SpaceBeforeCaseColon: true
+SpaceBeforeCpp11BracedList: false
+SpaceBeforeInheritanceColon: false
+SpaceInEmptyBlock: false
+SpacesBeforeTrailingComments: 2

.git-blame-ignore-revs

@@ -0,0 +1,7 @@
+# .git-blame-ignore-revs
+# Ignore commit which added clang-format
+2d0237db3f0e596fb06e3ffbadba84dcc4e018f6
+
+# Post commit formatting fixes
+0fca5605fa2e5e7240fde5e1aae50952b2612231
+08ed4c90db31959521b7ef3186c026edd1e90307

.github/ISSUE_TEMPLATE/config.yml

@@ -2,7 +2,7 @@ blank_issues_enabled: false
 contact_links:
   - name: Discord server
     url: https://discord.gg/GWDRS3kU6R
-    about: Feel free to ask for support or have a chat with us in our Discord server!
+    about: Feel free to ask for support or have a chat with us on our Discord server!
   - name: Discussions, Q&A, ideas, show us something...
     url: https://github.com/official-stockfish/Stockfish/discussions/new
     about: Do you have an idea for Stockfish? Do you want to show something that you made? Please open a discussion about it!

.github/ci/arm_matrix.json

@@ -0,0 +1,51 @@
+{
+  "config": [
+    {
+      "name": "Android NDK aarch64",
+      "os": "ubuntu-22.04",
+      "simple_name": "android",
+      "compiler": "aarch64-linux-android21-clang++",
+      "emu": "qemu-aarch64",
+      "comp": "ndk",
+      "shell": "bash",
+      "archive_ext": "tar"
+    },
+    {
+      "name": "Android NDK arm",
+      "os": "ubuntu-22.04",
+      "simple_name": "android",
+      "compiler": "armv7a-linux-androideabi21-clang++",
+      "emu": "qemu-arm",
+      "comp": "ndk",
+      "shell": "bash",
+      "archive_ext": "tar"
+    }
+  ],
+  "binaries": ["armv8-dotprod", "armv8", "armv7", "armv7-neon"],
+  "exclude": [
+    {
+      "binaries": "armv8-dotprod",
+      "config": {
+        "compiler": "armv7a-linux-androideabi21-clang++"
+      }
+    },
+    {
+      "binaries": "armv8",
+      "config": {
+        "compiler": "armv7a-linux-androideabi21-clang++"
+      }
+    },
+    {
+      "binaries": "armv7",
+      "config": {
+        "compiler": "aarch64-linux-android21-clang++"
+      }
+    },
+    {
+      "binaries": "armv7-neon",
+      "config": {
+        "compiler": "aarch64-linux-android21-clang++"
+      }
+    }
+  ]
+}

.github/ci/libcxx17.imp

@@ -0,0 +1,21 @@
+[
+    # Mappings for libcxx's internal headers
+    { include: [ "<__fwd/fstream.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/ios.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/istream.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/ostream.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/sstream.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/streambuf.h>", private, "<iosfwd>", public ] },
+    { include: [ "<__fwd/string_view.h>", private, "<string_view>", public ] },
+
+    # Mappings for includes between public headers
+    { include: [ "<ios>", public, "<iostream>", public ] },
+    { include: [ "<streambuf>", public, "<iostream>", public ] },
+    { include: [ "<istream>", public, "<iostream>", public ] },
+    { include: [ "<ostream>", public, "<iostream>", public ] },
+    { include: [ "<iosfwd>", public, "<iostream>", public ] },
+
+    # Missing mappings in include-what-you-use's libcxx.imp
+    { include: ["@<__condition_variable/.*>", private, "<condition_variable>", public ] },
+    { include: ["@<__mutex/.*>", private, "<mutex>", public ] },
+]

.github/ci/matrix.json

@@ -0,0 +1,160 @@
+{
+  "config": [
+    {
+      "name": "Ubuntu 20.04 GCC",
+      "os": "ubuntu-20.04",
+      "simple_name": "ubuntu",
+      "compiler": "g++",
+      "comp": "gcc",
+      "shell": "bash",
+      "archive_ext": "tar",
+      "sde": "/home/runner/work/Stockfish/Stockfish/.output/sde-temp-files/sde-external-9.27.0-2023-09-13-lin/sde -future --"
+    },
+    {
+      "name": "MacOS 13 Apple Clang",
+      "os": "macos-13",
+      "simple_name": "macos",
+      "compiler": "clang++",
+      "comp": "clang",
+      "shell": "bash",
+      "archive_ext": "tar"
+    },
+    {
+      "name": "MacOS 14 Apple Clang M1",
+      "os": "macos-14",
+      "simple_name": "macos-m1",
+      "compiler": "clang++",
+      "comp": "clang",
+      "shell": "bash",
+      "archive_ext": "tar"
+    },
+    {
+      "name": "Windows 2022 Mingw-w64 GCC x86_64",
+      "os": "windows-2022",
+      "simple_name": "windows",
+      "compiler": "g++",
+      "comp": "mingw",
+      "msys_sys": "mingw64",
+      "msys_env": "x86_64-gcc",
+      "shell": "msys2 {0}",
+      "ext": ".exe",
+      "sde": "/d/a/Stockfish/Stockfish/.output/sde-temp-files/sde-external-9.27.0-2023-09-13-win/sde.exe -future --",
+      "archive_ext": "zip"
+    }
+  ],
+  "binaries": [
+    "x86-64",
+    "x86-64-sse41-popcnt",
+    "x86-64-avx2",
+    "x86-64-bmi2",
+    "x86-64-avxvnni",
+    "x86-64-avx512",
+    "x86-64-vnni256",
+    "x86-64-vnni512",
+    "apple-silicon"
+  ],
+  "exclude": [
+    {
+      "binaries": "x86-64",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-sse41-popcnt",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-avx2",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-bmi2",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-avxvnni",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-avxvnni",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-avx512",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-vnni256",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-vnni512",
+      "config": {
+        "os": "macos-14"
+      }
+    },
+    {
+      "binaries": "x86-64-avxvnni",
+      "config": {
+        "ubuntu-20.04": null
+      }
+    },
+    {
+      "binaries": "x86-64-avxvnni",
+      "config": {
+        "os": "macos-13"
+      }
+    },
+    {
+      "binaries": "x86-64-avx512",
+      "config": {
+        "os": "macos-13"
+      }
+    },
+    {
+      "binaries": "x86-64-vnni256",
+      "config": {
+        "os": "macos-13"
+      }
+    },
+    {
+      "binaries": "x86-64-vnni512",
+      "config": {
+        "os": "macos-13"
+      }
+    },
+    {
+      "binaries": "apple-silicon",
+      "config": {
+        "os": "windows-2022"
+      }
+    },
+    {
+      "binaries": "apple-silicon",
+      "config": {
+        "os": "macos-13"
+      }
+    },
+    {
+      "binaries": "apple-silicon",
+      "config": {
+        "os": "ubuntu-20.04"
+      }
+    }
+  ]
+}

.github/workflows/arm_compilation.yml

@@ -0,0 +1,94 @@
+name: Compilation
+on:
+  workflow_call:
+    inputs:
+      matrix:
+        type: string
+        required: true
+jobs:
+  Compilation:
+    name: ${{ matrix.config.name }} ${{ matrix.binaries }}
+    runs-on: ${{ matrix.config.os }}
+    env:
+      COMPILER: ${{ matrix.config.compiler }}
+      COMP: ${{ matrix.config.comp }}
+      EMU: ${{ matrix.config.emu }}
+      EXT: ${{ matrix.config.ext }}
+      BINARY: ${{ matrix.binaries }}
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(inputs.matrix) }}
+    defaults:
+      run:
+        working-directory: src
+        shell: ${{ matrix.config.shell }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Download required linux packages
+        if: runner.os == 'Linux'
+        run: |
+          sudo apt update
+          sudo apt install qemu-user
+
+      - name: Install NDK
+        if: runner.os == 'Linux'
+        run: |
+          if [ $COMP == ndk ]; then
+            NDKV="21.4.7075529"
+            ANDROID_ROOT=/usr/local/lib/android
+            ANDROID_SDK_ROOT=$ANDROID_ROOT/sdk
+            SDKMANAGER=$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager
+            echo "y" | $SDKMANAGER "ndk;$NDKV"
+            ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk/$NDKV
+            ANDROID_NDK_BIN=$ANDROID_NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/bin
+            echo "ANDROID_NDK_BIN=$ANDROID_NDK_BIN" >> $GITHUB_ENV
+          fi
+
+      - name: Extract the bench number from the commit history
+        run: |
+          for hash in $(git rev-list -100 HEAD); do
+            benchref=$(git show -s $hash | tac | grep -m 1 -o -x '[[:space:]]*\b[Bb]ench[ :]\+[1-9][0-9]\{5,7\}\b[[:space:]]*' | sed 's/[^0-9]//g') && break || true
+          done
+          [[ -n "$benchref" ]] && echo "benchref=$benchref" >> $GITHUB_ENV && echo "From commit: $hash" && echo "Reference bench: $benchref" || echo "No bench found"
+
+      - name: Download the used network from the fishtest framework
+        run: make net
+
+      - name: Check compiler
+        run: |
+          if [ $COMP == ndk ]; then
+            export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
+          fi
+          $COMPILER -v
+
+      - name: Test help target
+        run: make help
+
+      - name: Check git
+        run: git --version
+
+      # Compile profile guided builds
+
+      - name: Compile ${{ matrix.binaries }} build
+        run: |
+          if [ $COMP == ndk ]; then
+            export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
+            export LDFLAGS="-static -Wno-unused-command-line-argument"
+          fi
+          make clean
+          make -j4 profile-build ARCH=$BINARY COMP=$COMP WINE_PATH=$EMU
+          make strip ARCH=$BINARY COMP=$COMP
+          WINE_PATH=$EMU ../tests/signature.sh $benchref
+          mv ./stockfish$EXT ../stockfish-android-$BINARY$EXT
+
+      - name: Remove non src files
+        run: git clean -fx
+
+      - name: Upload artifact for (pre)-release
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
+          path: .

.github/workflows/clang-format.yml

@@ -0,0 +1,51 @@
+# This workflow will run clang-format and comment on the PR.
+# Because of security reasons, it is crucial that this workflow
+# executes no shell script nor runs make.
+# Read this before editing: https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
+
+name: Clang-Format
+on:
+  pull_request_target:
+    branches:
+      - "master"
+    paths:
+      - "**.cpp"
+      - "**.h"
+jobs:
+  Clang-Format:
+    name: Clang-Format
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+
+      - name: Run clang-format style check
+        uses: jidicula/clang-format-action@f62da5e3d3a2d88ff364771d9d938773a618ab5e # @v4.11.0
+        id: clang-format
+        continue-on-error: true
+        with:
+          clang-format-version: "17"
+          exclude-regex: "incbin"
+
+      - name: Comment on PR
+        if: steps.clang-format.outcome == 'failure'
+        uses: thollander/actions-comment-pull-request@1d3973dc4b8e1399c0620d3f2b1aa5e795465308 # @v2.4.3
+        with:
+          message: |
+            clang-format 17 needs to be run on this PR.
+            If you do not have clang-format installed, the maintainer will run it when merging.
+            For the exact version please see https://packages.ubuntu.com/mantic/clang-format-17.
+
+            _(execution **${{ github.run_id }}** / attempt **${{ github.run_attempt }}**)_
+          comment_tag: execution
+
+      - name: Comment on PR
+        if: steps.clang-format.outcome != 'failure'
+        uses: thollander/actions-comment-pull-request@1d3973dc4b8e1399c0620d3f2b1aa5e795465308 # @v2.4.3
+        with:
+          message: |
+            _(execution **${{ github.run_id }}** / attempt **${{ github.run_attempt }}**)_
+          create_if_not_exists: false
+          comment_tag: execution
+          mode: delete

.github/workflows/codeql.yml

@@ -0,0 +1,53 @@
+name: "CodeQL"
+
+on:
+  push:
+    branches: ["master"]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: ["master"]
+  schedule:
+    - cron: "17 18 * * 1"
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: ["cpp"]
+        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
+        # Use only 'java' to analyze code written in Java, Kotlin, or both
+        # Use only 'javascript' to analyze code written in JavaScript, TypeScript or both
+        # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      # Initializes the CodeQL tools for scanning.
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: ${{ matrix.language }}
+          # If you wish to specify custom queries, you can do so here or in a config file.
+          # By default, queries listed here will override any specified in a config file.
+          # Prefix the list here with "+" to use these queries and those in the config file.
+
+          # For more details on CodeQL's query packs, refer to: https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
+          # queries: security-extended,security-and-quality
+
+      - name: Build
+        working-directory: src
+        run: make -j build ARCH=x86-64-modern
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: "/language:${{matrix.language}}"

.github/workflows/compilation.yml

@@ -0,0 +1,89 @@
+name: Compilation
+on:
+  workflow_call:
+    inputs:
+      matrix:
+        type: string
+        required: true
+jobs:
+  Compilation:
+    name: ${{ matrix.config.name }} ${{ matrix.binaries }}
+    runs-on: ${{ matrix.config.os }}
+    env:
+      COMPILER: ${{ matrix.config.compiler }}
+      COMP: ${{ matrix.config.comp }}
+      EXT: ${{ matrix.config.ext }}
+      NAME: ${{ matrix.config.simple_name }}
+      BINARY: ${{ matrix.binaries }}
+      SDE: ${{ matrix.config.sde }}
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(inputs.matrix) }}
+    defaults:
+      run:
+        working-directory: src
+        shell: ${{ matrix.config.shell }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install fixed GCC on Linux
+        if: runner.os == 'Linux'
+        uses: egor-tensin/setup-gcc@eaa888eb19115a521fa72b65cd94fe1f25bbcaac # @v1.3
+        with:
+          version: 11
+
+      - name: Setup msys and install required packages
+        if: runner.os == 'Windows'
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: ${{ matrix.config.msys_sys }}
+          install: mingw-w64-${{ matrix.config.msys_env }} make git zip
+
+      - name: Download SDE package
+        if: runner.os == 'Linux' || runner.os == 'Windows'
+        uses: petarpetrovt/setup-sde@91a1a03434384e064706634125a15f7446d2aafb # @v2.3
+        with:
+          environmentVariableName: SDE_DIR
+          sdeVersion: 9.27.0
+
+      - name: Download the used network from the fishtest framework
+        run: make net
+
+      - name: Check compiler
+        run: $COMPILER -v
+
+      - name: Test help target
+        run: make help
+
+      - name: Check git
+        run: git --version
+
+      - name: Check compiler
+        run: $COMPILER -v
+
+      - name: Show g++ cpu info
+        if: runner.os != 'macOS'
+        run: g++ -Q -march=native --help=target
+
+      - name: Show clang++ cpu info
+        if: runner.os == 'macOS'
+        run: clang++ -E - -march=native -###
+
+      # x86-64 with newer extensions tests
+
+      - name: Compile ${{ matrix.config.binaries }} build
+        run: |
+          make clean
+          make -j4 profile-build ARCH=$BINARY COMP=$COMP WINE_PATH="$SDE"
+          make strip ARCH=$BINARY COMP=$COMP
+          WINE_PATH="$SDE" ../tests/signature.sh $benchref
+          mv ./stockfish$EXT ../stockfish-$NAME-$BINARY$EXT
+
+      - name: Remove non src files
+        run: git clean -fx
+
+      - name: Upload artifact for (pre)-release
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
+          path: .

.github/workflows/iwyu.yml

@@ -0,0 +1,47 @@
+name: IWYU
+on:
+  workflow_call:
+jobs:
+  Analyzers:
+    name: Check includes
+    runs-on: ubuntu-22.04
+    defaults:
+      run:
+        working-directory: Stockfish/src
+        shell: bash
+    steps:
+      - name: Checkout Stockfish
+        uses: actions/checkout@v4
+        with:
+          path: Stockfish
+
+      - name: Checkout include-what-you-use
+        uses: actions/checkout@v4
+        with:
+          repository: include-what-you-use/include-what-you-use
+          ref: f25caa280dc3277c4086ec345ad279a2463fea0f
+          path: include-what-you-use
+
+      - name: Download required linux packages
+        run: |
+          sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-17 main'
+          wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+          sudo apt update
+          sudo apt install -y libclang-17-dev clang-17 libc++-17-dev
+
+      - name: Set up include-what-you-use
+        run: |
+          mkdir build && cd build
+          cmake -G "Unix Makefiles" -DCMAKE_PREFIX_PATH="/usr/lib/llvm-17" ..
+          sudo make install
+        working-directory: include-what-you-use
+
+      - name: Check include-what-you-use
+        run: include-what-you-use --version
+
+      - name: Check includes
+        run: >
+          make analyze
+          COMP=clang
+          CXX=include-what-you-use
+          CXXFLAGS="-stdlib=libc++ -Xiwyu --comment_style=long -Xiwyu --mapping='${{ github.workspace }}/Stockfish/.github/ci/libcxx17.imp' -Xiwyu --error"

.github/workflows/sanitizers.yml

@@ -1,8 +1,8 @@
-name: Stockfish
+name: Sanitizers
 on:
   workflow_call:
 jobs:
-  Stockfish:
+  Test-under-sanitizers:
     name: ${{ matrix.sanitizers.name }}
     runs-on: ${{ matrix.config.os }}
     env:
@@ -10,13 +10,14 @@ jobs:
       COMP: ${{ matrix.config.comp }}
       CXXFLAGS: "-Werror"
     strategy:
+      fail-fast: false
       matrix:
         config:
-          - name: Ubuntu 20.04 GCC
-            os: ubuntu-20.04
+          - name: Ubuntu 22.04 GCC
+            os: ubuntu-22.04
             compiler: g++
             comp: gcc
-            shell: bash {0}
+            shell: bash
         sanitizers:
           - name: Run with thread sanitizer
             make_option: sanitize=thread
@@ -35,9 +36,7 @@ jobs:
         working-directory: src
         shell: ${{ matrix.config.shell }}
     steps:
-      - uses: actions/checkout@v3
-        with:
-          fetch-depth: 0
+      - uses: actions/checkout@v4
 
       - name: Download required linux packages
         run: |
@@ -62,5 +61,5 @@ jobs:
         run: |
           export CXXFLAGS="-O1 -fno-inline"
           make clean
-          make -j2 ARCH=x86-64-modern ${{ matrix.sanitizers.make_option }} debug=yes optimize=no build > /dev/null
+          make -j4 ARCH=x86-64-sse41-popcnt ${{ matrix.sanitizers.make_option }} debug=yes optimize=no build > /dev/null
           ../tests/instrumented.sh --${{ matrix.sanitizers.instrumented_option }}

.github/workflows/stockfish.yml

@@ -1,8 +1,8 @@
 name: Stockfish
 on:
   push:
-    tags:        
-      - '*' 
+    tags:
+      - "*"
     branches:
       - master
       - tools
@@ -13,13 +13,9 @@ on:
       - tools
 jobs:
   Prerelease:
-    if: github.ref == 'refs/heads/master'
+    if: github.repository == 'official-stockfish/Stockfish' && (github.ref == 'refs/heads/master' || (startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag'))
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-        with:
-          fetch-depth: 0
-
       # returns null if no pre-release exists
       - name: Get Commit SHA of Latest Pre-release
         run: |
@@ -29,23 +25,52 @@ jobs:
 
           echo "COMMIT_SHA=$(jq -r 'map(select(.prerelease)) | first | .tag_name' <<< $(curl -s https://api.github.com/repos/${{ github.repository_owner }}/Stockfish/releases))" >> $GITHUB_ENV
 
-      # delete old previous pre-release and tag
-      - uses: dev-drprasad/delete-tag-and-release@v0.2.1
+        # delete old previous pre-release and tag
+      - uses: actions/checkout@v4
+      - run: gh release delete ${{ env.COMMIT_SHA }} --cleanup-tag
         if: env.COMMIT_SHA != 'null'
-        with:
-          tag_name: ${{ env.COMMIT_SHA }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
+  Matrix:
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.set-matrix.outputs.matrix }}
+      arm_matrix: ${{ steps.set-arm-matrix.outputs.arm_matrix }}
+    steps:
+      - uses: actions/checkout@v4
+      - id: set-matrix
+        run: |
+          TASKS=$(echo $(cat .github/ci/matrix.json) )
+          echo "MATRIX=$TASKS" >> $GITHUB_OUTPUT
+      - id: set-arm-matrix
+        run: |
+          TASKS_ARM=$(echo $(cat .github/ci/arm_matrix.json) )
+          echo "ARM_MATRIX=$TASKS_ARM" >> $GITHUB_OUTPUT
+  Compilation:
+    needs: [Matrix]
+    uses: ./.github/workflows/compilation.yml
+    with:
+      matrix: ${{ needs.Matrix.outputs.matrix }}
+  ARMCompilation:
+    needs: [Matrix]
+    uses: ./.github/workflows/arm_compilation.yml
+    with:
+      matrix: ${{ needs.Matrix.outputs.arm_matrix }}
+  IWYU:
+    uses: ./.github/workflows/iwyu.yml
   Sanitizers:
-    uses: ./.github/workflows/stockfish_sanitizers.yml
+    uses: ./.github/workflows/sanitizers.yml
   Tests:
-    uses: ./.github/workflows/stockfish_test.yml
-  Compiles:
-    uses: ./.github/workflows/stockfish_compile_test.yml
+    uses: ./.github/workflows/tests.yml
   Binaries:
-    if: github.ref == 'refs/heads/master' || (startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag')
-    uses: ./.github/workflows/stockfish_binaries.yml
+    if: github.repository == 'official-stockfish/Stockfish'
+    needs: [Matrix, Prerelease, Compilation]
+    uses: ./.github/workflows/upload_binaries.yml
+    with:
+      matrix: ${{ needs.Matrix.outputs.matrix }}
   ARM_Binaries:
-    if: github.ref == 'refs/heads/master' || (startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag')
-    uses: ./.github/workflows/stockfish_arm_binaries.yml
+    if: github.repository == 'official-stockfish/Stockfish'
+    needs: [Matrix, Prerelease, ARMCompilation]
+    uses: ./.github/workflows/upload_binaries.yml
+    with:
+      matrix: ${{ needs.Matrix.outputs.arm_matrix }}

.github/workflows/stockfish_arm_binaries.yml

@@ -1,158 +0,0 @@
-name: Stockfish
-on:
-  workflow_call:
-jobs:
-  Stockfish:
-    name: ${{ matrix.config.name }} ${{ matrix.binaries }}
-    runs-on: ${{ matrix.config.os }}
-    env:
-      COMPILER: ${{ matrix.config.compiler }}
-      COMP: ${{ matrix.config.comp }}
-      EMU: ${{ matrix.config.emu }}
-      EXT: ${{ matrix.config.ext }}
-      OS: ${{ matrix.config.os }}
-      BINARY: ${{ matrix.binaries }}
-    strategy:
-      matrix:
-        config:
-          - name: Android NDK aarch64
-            os: ubuntu-22.04
-            compiler: aarch64-linux-android21-clang++
-            emu: qemu-aarch64
-            comp: ndk
-            shell: bash {0}
-          - name: Android NDK arm
-            os: ubuntu-22.04
-            compiler: armv7a-linux-androideabi21-clang++
-            emu: qemu-arm
-            comp: ndk
-            shell: bash {0}
-        binaries:
-          - armv8
-          - armv7
-          - armv7-neon
-        exclude:
-          - binaries: armv8
-            config: {compiler: armv7a-linux-androideabi21-clang++}
-          - binaries: armv7
-            config: {compiler: aarch64-linux-android21-clang++}
-          - binaries: armv7-neon
-            config: {compiler: aarch64-linux-android21-clang++}
-    defaults:
-      run:
-        working-directory: src
-        shell: ${{ matrix.config.shell }}
-    steps:
-      - uses: actions/checkout@v3
-        with:
-          fetch-depth: 0
-
-      - name: Download required linux packages
-        if: runner.os == 'Linux'
-        run: |
-          sudo apt update
-          sudo apt install qemu-user
-
-      - name: Install NDK
-        if: runner.os == 'Linux'
-        run: |
-          if [ $COMP == ndk ]; then
-            NDKV="21.4.7075529"
-            ANDROID_ROOT=/usr/local/lib/android
-            ANDROID_SDK_ROOT=$ANDROID_ROOT/sdk
-            SDKMANAGER=$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager
-            echo "y" | $SDKMANAGER "ndk;$NDKV"
-            ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk/$NDKV
-            ANDROID_NDK_BIN=$ANDROID_NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/bin
-            echo "ANDROID_NDK_BIN=$ANDROID_NDK_BIN" >> $GITHUB_ENV
-          fi
-
-      - name: Download the used network from the fishtest framework
-        run: make net
-
-      - name: Check compiler
-        run: |
-          if [ $COMP == ndk ]; then
-            export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
-          fi
-          $COMPILER -v
-
-      - name: Test help target
-        run: make help
-
-      - name: Check git
-        run: git --version
-
-      # Compile profile guided builds
-
-      - name: Compile ${{ matrix.binaries }} build
-        run: |
-          if [ $COMP == ndk ]; then
-            export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
-            export LDFLAGS="-static -Wno-unused-command-line-argument"
-          fi
-          make clean
-          make -j2 profile-build ARCH=$BINARY COMP=$COMP WINE_PATH=$EMU
-          make strip ARCH=$BINARY COMP=$COMP
-          mv ./stockfish$EXT ../stockfish-android-$BINARY$EXT
-
-      - name: Remove non src files
-        run: rm -f *.o .depend *.nnue
-
-      - name: Download wiki
-        run: |
-          git clone https://github.com/official-stockfish/Stockfish.wiki.git ../wiki
-          cd ../wiki
-          rm -rf .git
-
-      - name: Create tar archive.
-        run: |
-          cd ..
-          mkdir stockfish
-          cp -r wiki stockfish/
-          cp -r src stockfish/
-          cp stockfish-android-$BINARY$EXT stockfish/
-          cp "Top CPU Contributors.txt" stockfish/
-          cp Copying.txt stockfish/
-          cp AUTHORS stockfish/
-          cp CITATION.cff stockfish/
-          cp README.md stockfish/
-          tar -cvf stockfish-android-$BINARY.tar stockfish
-
-      - name: Upload binaries
-        uses: actions/upload-artifact@v3
-        with:
-          name: stockfish-android-${{ matrix.binaries }}
-          path: stockfish-android-${{ matrix.binaries }}.tar
-
-      - name: Release
-        if: startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag'
-        uses: softprops/action-gh-release@v1
-        with:
-          files: stockfish-android-${{ matrix.binaries }}.tar
-
-      - name: Get last commit sha
-        id: last_commit
-        run: echo "COMMIT_SHA=$(git rev-parse HEAD | cut -c 1-8)" >> $GITHUB_ENV
-
-      - name: Get commit date
-        id: commit_date
-        run: echo "COMMIT_DATE=$(git show -s --date=format:'%Y%m%d' --format=%cd HEAD)" >> $GITHUB_ENV
-
-      # Make sure that an old ci which still runs on master doesn't recreate a prerelease
-      - name: Check Pullable Commits
-        id: check_commits
-        run: |
-          git fetch
-          CHANGES=$(git rev-list HEAD..origin/master --count)
-          echo "CHANGES=$CHANGES" >> $GITHUB_ENV
-
-      - name: Prerelease
-        if: github.ref_name == 'master' && env.CHANGES == '0'
-        continue-on-error: true
-        uses: softprops/action-gh-release@v1
-        with:
-          name: Stockfish dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
-          tag_name: stockfish-dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
-          prerelease: true
-          files: stockfish-android-${{ matrix.binaries }}.tar

.github/workflows/stockfish_binaries.yml

@@ -1,168 +0,0 @@
-name: Stockfish
-on:
-  workflow_call:
-jobs:
-  Stockfish:
-    name: ${{ matrix.config.name }} ${{ matrix.binaries }}
-    runs-on: ${{ matrix.config.os }}
-    env:
-      COMPILER: ${{ matrix.config.compiler }}
-      COMP: ${{ matrix.config.comp }}
-      EXT: ${{ matrix.config.ext }}
-      NAME: ${{ matrix.config.simple_name }}
-      BINARY: ${{ matrix.binaries }}
-    strategy:
-      matrix:
-        config:
-          - name: Ubuntu 20.04 GCC
-            os: ubuntu-20.04
-            simple_name: ubuntu
-            compiler: g++
-            comp: gcc
-            shell: bash {0}
-            archive_ext: tar
-          - name: MacOS 12 Apple Clang
-            os: macos-12
-            simple_name: macos
-            compiler: clang++
-            comp: clang
-            shell: bash {0}
-            archive_ext: tar
-          - name: Windows 2022 Mingw-w64 GCC x86_64
-            os: windows-2022
-            simple_name: windows
-            compiler: g++
-            comp: mingw
-            msys_sys: mingw64
-            msys_env: x86_64-gcc
-            shell: msys2 {0}
-            ext: .exe
-            archive_ext: zip
-        binaries:
-          - x86-64
-          - x86-64-modern
-          - x86-64-avx2
-        exclude:
-          - binaries: x86-64-avx2
-            config: {os: macos-12}
-    defaults:
-      run:
-        working-directory: src
-        shell: ${{ matrix.config.shell }}
-    steps:
-      - uses: actions/checkout@v3
-        with:
-          fetch-depth: 0
-
-      - name: Download required linux packages
-        if: runner.os == 'Linux'
-        run: sudo apt update
-
-      - name: Setup msys and install required packages
-        if: runner.os == 'Windows'
-        uses: msys2/setup-msys2@v2
-        with:
-          msystem: ${{ matrix.config.msys_sys }}
-          install: mingw-w64-${{ matrix.config.msys_env }} make git zip
-
-      - name: Download the used network from the fishtest framework
-        run: make net
-
-      - name: Check compiler
-        run: $COMPILER -v
-
-      - name: Test help target
-        run: make help
-
-      - name: Check git
-        run: git --version
-
-      # Compile profile guided builds
-
-      - name: Compile ${{ matrix.binaries }} build
-        run: |
-          make -j2 profile-build ARCH=$BINARY COMP=$COMP
-          make strip ARCH=$BINARY COMP=$COMP
-          mv ./stockfish$EXT ../stockfish-$NAME-$BINARY$EXT
-
-      - name: Remove non src files
-        run: git clean -fx
-
-      - name: Download wiki
-        run: |
-          git clone https://github.com/official-stockfish/Stockfish.wiki.git ../wiki
-          rm -rf ../wiki/.git
-
-      - name: Create directory.
-        run: |
-          cd ..
-          mkdir stockfish
-          cp -r wiki stockfish/
-          cp -r src stockfish/
-          cp stockfish-$NAME-$BINARY$EXT stockfish/
-          cp "Top CPU Contributors.txt" stockfish/
-          cp Copying.txt stockfish/
-          cp AUTHORS stockfish/
-          cp CITATION.cff stockfish/
-          cp README.md stockfish/
-
-      - name: Create tar
-        if: runner.os != 'Windows'
-        run: |
-          cd ..
-          tar -cvf stockfish-$NAME-$BINARY.tar stockfish
-
-      - name: Create zip
-        if: runner.os == 'Windows'
-        run: |
-          cd ..
-          zip -r stockfish-$NAME-$BINARY.zip stockfish
-
-      - name: Upload binaries
-        if: runner.os != 'Windows'
-        uses: actions/upload-artifact@v3
-        with:
-          name: stockfish-${{ matrix.config.os }}-${{ matrix.binaries }}
-          path: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.tar
-
-      # Artifacts automatically get zipped
-      # to avoid double zipping, we use the unzipped directory
-      - name: Upload binaries
-        if: runner.os == 'Windows'
-        uses: actions/upload-artifact@v3
-        with:
-          name: stockfish-${{ matrix.config.os }}-${{ matrix.binaries }}
-          path: stockfish
-
-      - name: Release
-        if: startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag'
-        uses: softprops/action-gh-release@v1
-        with:
-          files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}
-
-      - name: Get last commit sha
-        id: last_commit
-        run: echo "COMMIT_SHA=$(git rev-parse HEAD | cut -c 1-8)" >> $GITHUB_ENV
-
-      - name: Get commit date
-        id: commit_date
-        run: echo "COMMIT_DATE=$(git show -s --date=format:'%Y%m%d' --format=%cd HEAD)" >> $GITHUB_ENV
-
-      # Make sure that an old ci which still runs on master doesn't recreate a prerelease
-      - name: Check Pullable Commits
-        id: check_commits
-        run: |
-          git fetch
-          CHANGES=$(git rev-list HEAD..origin/master --count)
-          echo "CHANGES=$CHANGES" >> $GITHUB_ENV
-
-      - name: Prerelease
-        if: github.ref_name == 'master' && env.CHANGES == '0'
-        continue-on-error: true
-        uses: softprops/action-gh-release@v1
-        with:
-          name: Stockfish dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
-          tag_name: stockfish-dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
-          prerelease: true
-          files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}
-

.github/workflows/stockfish_compile_test.yml

@@ -1,102 +0,0 @@
-name: Stockfish
-on:
-  workflow_call:
-jobs:
-  Stockfish:
-    name: ${{ matrix.config.name }}
-    runs-on: ${{ matrix.config.os }}
-    env:
-      COMPILER: ${{ matrix.config.compiler }}
-      COMP: ${{ matrix.config.comp }}
-    strategy:
-      matrix:
-        config:
-          - name: Ubuntu 20.04 GCC
-            os: ubuntu-20.04
-            compiler: g++
-            comp: gcc
-            shell: bash {0}
-          - name: Ubuntu 20.04 Clang
-            os: ubuntu-20.04
-            compiler: clang++
-            comp: clang
-            shell: bash {0}
-          - name: MacOS 12 Apple Clang
-            os: macos-12
-            compiler: clang++
-            comp: clang
-            shell: bash {0}
-          - name: MacOS 12 GCC 11
-            os: macos-12
-            compiler: g++-11
-            comp: gcc
-            shell: bash {0}
-          - name: Windows 2022 Mingw-w64 GCC x86_64
-            os: windows-2022
-            compiler: g++
-            comp: mingw
-            msys_sys: mingw64
-            msys_env: x86_64-gcc
-            shell: msys2 {0}
-          - name: Windows 2022 Mingw-w64 Clang x86_64
-            os: windows-2022
-            compiler: clang++
-            comp: clang
-            msys_sys: clang64
-            msys_env: clang-x86_64-clang
-            shell: msys2 {0}
-
-    defaults:
-      run:
-        working-directory: src
-        shell: ${{ matrix.config.shell }}
-    steps:
-      - uses: actions/checkout@v3
-        with:
-          fetch-depth: 0
-
-      - name: Setup msys and install required packages
-        if: runner.os == 'Windows'
-        uses: msys2/setup-msys2@v2
-        with:
-          msystem: ${{matrix.config.msys_sys}}
-          install: mingw-w64-${{matrix.config.msys_env}} make git
-
-      - name: Download the used network from the fishtest framework
-        run: make net
-
-      - name: Check compiler
-        run: $COMPILER -v
-
-      - name: Test help target
-        run: make help
-
-      - name: Check git
-        run: git --version
-
-      # x86-64 with newer extensions tests
-
-      - name: Compile x86-64-avx2 build
-        run: |
-          make clean
-          make -j2 ARCH=x86-64-avx2 build
-
-      - name: Compile x86-64-bmi2 build
-        run: |
-          make clean
-          make -j2 ARCH=x86-64-bmi2 build
-
-      - name: Compile x86-64-avx512 build
-        run: |
-          make clean
-          make -j2 ARCH=x86-64-avx512 build
-
-      - name: Compile x86-64-vnni512 build
-        run: |
-          make clean
-          make -j2 ARCH=x86-64-vnni512 build
-
-      - name: Compile x86-64-vnni256 build
-        run: |
-          make clean
-          make -j2 ARCH=x86-64-vnni256 build

.github/workflows/tests.yml

@@ -1,8 +1,8 @@
-name: Stockfish
+name: Tests
 on:
   workflow_call:
 jobs:
-  Stockfish:
+  Test-Targets:
     name: ${{ matrix.config.name }}
     runs-on: ${{ matrix.config.os }}
     env:
@@ -10,6 +10,7 @@ jobs:
       COMP: ${{ matrix.config.comp }}
       CXXFLAGS: "-Werror"
     strategy:
+      fail-fast: false
       matrix:
         config:
           - name: Ubuntu 20.04 GCC
@@ -18,38 +19,61 @@ jobs:
             comp: gcc
             run_32bit_tests: true
             run_64bit_tests: true
-            shell: bash {0}
+            shell: bash
           - name: Ubuntu 20.04 Clang
             os: ubuntu-20.04
             compiler: clang++
             comp: clang
             run_32bit_tests: true
             run_64bit_tests: true
-            shell: bash {0}
+            shell: bash
           - name: Android NDK aarch64
             os: ubuntu-22.04
             compiler: aarch64-linux-android21-clang++
             comp: ndk
             run_armv8_tests: true
-            shell: bash {0}
+            shell: bash
           - name: Android NDK arm
             os: ubuntu-22.04
             compiler: armv7a-linux-androideabi21-clang++
             comp: ndk
             run_armv7_tests: true
-            shell: bash {0}
-          - name: MacOS 12 Apple Clang
-            os: macos-12
+            shell: bash
+          - name: Linux GCC riscv64
+            os: ubuntu-22.04
+            compiler: g++
+            comp: gcc
+            run_riscv64_tests: true
+            base_image: "riscv64/alpine:edge"
+            platform: linux/riscv64
+            shell: bash
+          - name: Linux GCC ppc64
+            os: ubuntu-22.04
+            compiler: g++
+            comp: gcc
+            run_ppc64_tests: true
+            base_image: "ppc64le/alpine:latest"
+            platform: linux/ppc64le
+            shell: bash
+          - name: MacOS 13 Apple Clang
+            os: macos-13
             compiler: clang++
             comp: clang
             run_64bit_tests: true
-            shell: bash {0}
-          - name: MacOS 12 GCC 11
-            os: macos-12
+            shell: bash
+          - name: MacOS 14 Apple Clang M1
+            os: macos-14
+            compiler: clang++
+            comp: clang
+            run_64bit_tests: false
+            run_m1_tests: true
+            shell: bash
+          - name: MacOS 13 GCC 11
+            os: macos-13
             compiler: g++-11
             comp: gcc
             run_64bit_tests: true
-            shell: bash {0}
+            shell: bash
           - name: Windows 2022 Mingw-w64 GCC x86_64
             os: windows-2022
             compiler: g++
@@ -79,7 +103,7 @@ jobs:
         working-directory: src
         shell: ${{ matrix.config.shell }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
@@ -87,7 +111,7 @@ jobs:
         if: runner.os == 'Linux'
         run: |
           sudo apt update
-          sudo apt install expect valgrind g++-multilib qemu-user
+          sudo apt install expect valgrind g++-multilib qemu-user-static
 
       - name: Install NDK
         if: runner.os == 'Linux'
@@ -103,6 +127,28 @@ jobs:
             echo "ANDROID_NDK_BIN=$ANDROID_NDK_BIN" >> $GITHUB_ENV
           fi
 
+      - name: Set up QEMU
+        if: matrix.config.base_image
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker Buildx
+        if: matrix.config.base_image
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build Docker container
+        if: matrix.config.base_image
+        run: |
+          docker buildx build --load -t sf_builder - << EOF
+          FROM ${{ matrix.config.base_image }}
+          WORKDIR /app
+          RUN apk update && apk add make g++
+          CMD ["sh", "script.sh"]
+          EOF
+
+      - name: Download required macOS packages
+        if: runner.os == 'macOS'
+        run: brew install coreutils
+
       - name: Setup msys and install required packages
         if: runner.os == 'Windows'
         uses: msys2/setup-msys2@v2
@@ -115,15 +161,22 @@ jobs:
 
       - name: Extract the bench number from the commit history
         run: |
-          git log HEAD | grep -o "\b[Bb]ench[ :]\+[1-9][0-9]\{5,9\}\b" | head -n 1 | sed "s/[^0-9]//g" > git_sig
-          [ -s git_sig ] && echo "benchref=$(cat git_sig)" >> $GITHUB_ENV && echo "Reference bench:" $(cat git_sig) || echo "No bench found"
+          for hash in $(git rev-list -100 HEAD); do
+            benchref=$(git show -s $hash | tac | grep -m 1 -o -x '[[:space:]]*\b[Bb]ench[ :]\+[1-9][0-9]\{5,7\}\b[[:space:]]*' | sed 's/[^0-9]//g') && break || true
+          done
+          [[ -n "$benchref" ]] && echo "benchref=$benchref" >> $GITHUB_ENV && echo "From commit: $hash" && echo "Reference bench: $benchref" || echo "No bench found"
 
       - name: Check compiler
         run: |
-          if [ $COMP == ndk ]; then
-            export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
+          if [ -z "${{ matrix.config.base_image }}" ]; then
+            if [ $COMP == ndk ]; then
+              export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
+            fi
+            $COMPILER -v
+          else
+            echo "$COMPILER -v" > script.sh
+            docker run --rm --platform ${{ matrix.config.platform }} -v ${{ github.workspace }}/src:/app sf_builder
           fi
-          $COMPILER -v
 
       - name: Test help target
         run: make help
@@ -134,123 +187,179 @@ jobs:
       # x86-32 tests
 
       - name: Test debug x86-32 build
-        if: ${{ matrix.config.run_32bit_tests }}
+        if: matrix.config.run_32bit_tests
         run: |
           export CXXFLAGS="-Werror -D_GLIBCXX_DEBUG"
           make clean
-          make -j2 ARCH=x86-32 optimize=no debug=yes build
+          make -j4 ARCH=x86-32 optimize=no debug=yes build
           ../tests/signature.sh $benchref
 
       - name: Test x86-32 build
-        if: ${{ matrix.config.run_32bit_tests }}
+        if: matrix.config.run_32bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-32 build
+          make -j4 ARCH=x86-32 build
           ../tests/signature.sh $benchref
 
       - name: Test x86-32-sse41-popcnt build
-        if: ${{ matrix.config.run_32bit_tests }}
+        if: matrix.config.run_32bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-32-sse41-popcnt build
+          make -j4 ARCH=x86-32-sse41-popcnt build
           ../tests/signature.sh $benchref
 
       - name: Test x86-32-sse2 build
-        if: ${{ matrix.config.run_32bit_tests }}
+        if: matrix.config.run_32bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-32-sse2 build
+          make -j4 ARCH=x86-32-sse2 build
           ../tests/signature.sh $benchref
 
       - name: Test general-32 build
-        if: ${{ matrix.config.run_32bit_tests }}
+        if: matrix.config.run_32bit_tests
         run: |
           make clean
-          make -j2 ARCH=general-32 build
+          make -j4 ARCH=general-32 build
           ../tests/signature.sh $benchref
 
       # x86-64 tests
 
-      - name: Test debug x86-64-modern build
-        if: ${{ matrix.config.run_64bit_tests }}
+      - name: Test debug x86-64-avx2 build
+        if: matrix.config.run_64bit_tests
         run: |
           export CXXFLAGS="-Werror -D_GLIBCXX_DEBUG"
           make clean
-          make -j2 ARCH=x86-64-modern optimize=no debug=yes build
+          make -j4 ARCH=x86-64-avx2 optimize=no debug=yes build
           ../tests/signature.sh $benchref
 
-      - name: Test x86-64-modern build
-        if: ${{ matrix.config.run_64bit_tests }}
+      - name: Test x86-64-bmi2 build
+        if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-64-modern build
+          make -j4 ARCH=x86-64-bmi2 build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64-avx2 build
+        if: matrix.config.run_64bit_tests
+        run: |
+          make clean
+          make -j4 ARCH=x86-64-avx2 build
+          ../tests/signature.sh $benchref
+
+      # Test a deprecated arch
+      - name: Test x86-64-modern build
+        if: matrix.config.run_64bit_tests
+        run: |
+          make clean
+          make -j4 ARCH=x86-64-modern build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64-sse41-popcnt build
+        if: matrix.config.run_64bit_tests
+        run: |
+          make clean
+          make -j4 ARCH=x86-64-sse41-popcnt build
           ../tests/signature.sh $benchref
 
       - name: Test x86-64-ssse3 build
-        if: ${{ matrix.config.run_64bit_tests }}
+        if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-64-ssse3 build
+          make -j4 ARCH=x86-64-ssse3 build
           ../tests/signature.sh $benchref
 
       - name: Test x86-64-sse3-popcnt build
-        if: ${{ matrix.config.run_64bit_tests }}
+        if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-64-sse3-popcnt build
+          make -j4 ARCH=x86-64-sse3-popcnt build
           ../tests/signature.sh $benchref
 
       - name: Test x86-64 build
-        if: ${{ matrix.config.run_64bit_tests }}
+        if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-64 build
+          make -j4 ARCH=x86-64 build
           ../tests/signature.sh $benchref
 
       - name: Test general-64 build
         if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=general-64 build
+          make -j4 ARCH=general-64 build
+          ../tests/signature.sh $benchref
+
+      - name: Test apple-silicon build
+        if: matrix.config.run_m1_tests
+        run: |
+          make clean
+          make -j4 ARCH=apple-silicon build
           ../tests/signature.sh $benchref
 
       # armv8 tests
 
       - name: Test armv8 build
-        if: ${{ matrix.config.run_armv8_tests }}
+        if: matrix.config.run_armv8_tests
         run: |
           export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
           export LDFLAGS="-static -Wno-unused-command-line-argument"
           make clean
-          make -j2 ARCH=armv8 build
+          make -j4 ARCH=armv8 build
+          ../tests/signature.sh $benchref
+
+      - name: Test armv8-dotprod build
+        if: matrix.config.run_armv8_tests
+        run: |
+          export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
+          export LDFLAGS="-static -Wno-unused-command-line-argument"
+          make clean
+          make -j4 ARCH=armv8-dotprod build
           ../tests/signature.sh $benchref
 
       # armv7 tests
 
       - name: Test armv7 build
-        if: ${{ matrix.config.run_armv7_tests }}
+        if: matrix.config.run_armv7_tests
         run: |
           export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
           export LDFLAGS="-static -Wno-unused-command-line-argument"
           make clean
-          make -j2 ARCH=armv7 build
+          make -j4 ARCH=armv7 build
           ../tests/signature.sh $benchref
 
       - name: Test armv7-neon build
-        if: ${{ matrix.config.run_armv7_tests }}
+        if: matrix.config.run_armv7_tests
         run: |
           export PATH=${{ env.ANDROID_NDK_BIN }}:$PATH
           export LDFLAGS="-static -Wno-unused-command-line-argument"
           make clean
-          make -j2 ARCH=armv7-neon build
+          make -j4 ARCH=armv7-neon build
+          ../tests/signature.sh $benchref
+
+      # riscv64 tests
+
+      - name: Test riscv64 build
+        if: matrix.config.run_riscv64_tests
+        run: |
+          echo "export LDFLAGS='-static' && make clean && make -j4 ARCH=riscv64 build" > script.sh
+          docker run --rm --platform ${{ matrix.config.platform }} -v ${{ github.workspace }}/src:/app sf_builder
+          ../tests/signature.sh $benchref
+
+      # ppc64 tests
+
+      - name: Test ppc64 build
+        if: matrix.config.run_ppc64_tests
+        run: |
+          echo "export LDFLAGS='-static' && make clean && make -j4 ARCH=ppc-64 build" > script.sh
+          docker run --rm --platform ${{ matrix.config.platform }} -v ${{ github.workspace }}/src:/app sf_builder
           ../tests/signature.sh $benchref
 
       # Other tests
 
       - name: Check perft and search reproducibility
-        if: ${{ matrix.config.run_64bit_tests }}
+        if: matrix.config.run_64bit_tests
         run: |
           make clean
-          make -j2 ARCH=x86-64-modern build
+          make -j4 ARCH=x86-64-avx2 build
           ../tests/perft.sh
           ../tests/reprosearch.sh

.github/workflows/upload_binaries.yml

@@ -0,0 +1,105 @@
+name: Upload Binaries
+on:
+  workflow_call:
+    inputs:
+      matrix:
+        type: string
+        required: true
+
+jobs:
+  Artifacts:
+    name: ${{ matrix.config.name }} ${{ matrix.binaries }}
+    runs-on: ${{ matrix.config.os }}
+    env:
+      COMPILER: ${{ matrix.config.compiler }}
+      COMP: ${{ matrix.config.comp }}
+      EXT: ${{ matrix.config.ext }}
+      NAME: ${{ matrix.config.simple_name }}
+      BINARY: ${{ matrix.binaries }}
+      SDE: ${{ matrix.config.sde }}
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(inputs.matrix) }}
+    defaults:
+      run:
+        shell: ${{ matrix.config.shell }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download artifact from compilation
+        uses: actions/download-artifact@v4
+        with:
+          name: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
+          path: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
+
+      - name: Setup msys and install required packages
+        if: runner.os == 'Windows'
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: ${{ matrix.config.msys_sys }}
+          install: mingw-w64-${{ matrix.config.msys_env }} make git zip
+
+      - name: Create Package
+        run: |
+          mkdir stockfish
+
+      - name: Download wiki
+        run: |
+          git clone https://github.com/official-stockfish/Stockfish.wiki.git wiki
+          rm -rf wiki/.git
+          mv wiki stockfish/
+
+      - name: Copy files
+        run: |
+          mv "${{ matrix.config.simple_name }} ${{ matrix.binaries }}" stockfish-workflow
+          cd stockfish-workflow
+          cp -r src ../stockfish/
+          cp stockfish-$NAME-$BINARY$EXT ../stockfish/
+          cp "Top CPU Contributors.txt" ../stockfish/
+          cp Copying.txt ../stockfish/
+          cp AUTHORS ../stockfish/
+          cp CITATION.cff ../stockfish/
+          cp README.md ../stockfish/
+          cp CONTRIBUTING.md ../stockfish/
+
+      - name: Create tar
+        if: runner.os != 'Windows'
+        run: |
+          tar -cvf stockfish-$NAME-$BINARY.tar stockfish
+
+      - name: Create zip
+        if: runner.os == 'Windows'
+        run: |
+          zip -r stockfish-$NAME-$BINARY.zip stockfish
+
+      - name: Release
+        if: startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag'
+        uses: softprops/action-gh-release@4634c16e79c963813287e889244c50009e7f0981
+        with:
+          files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}
+
+      - name: Get last commit sha
+        id: last_commit
+        run: echo "COMMIT_SHA=$(git rev-parse HEAD | cut -c 1-8)" >> $GITHUB_ENV
+
+      - name: Get commit date
+        id: commit_date
+        run: echo "COMMIT_DATE=$(git show -s --date=format:'%Y%m%d' --format=%cd HEAD)" >> $GITHUB_ENV
+
+      # Make sure that an old ci that still runs on master doesn't recreate a prerelease
+      - name: Check Pullable Commits
+        id: check_commits
+        run: |
+          git fetch
+          CHANGES=$(git rev-list HEAD..origin/master --count)
+          echo "CHANGES=$CHANGES" >> $GITHUB_ENV
+
+      - name: Prerelease
+        if: github.ref_name == 'master' && env.CHANGES == '0'
+        continue-on-error: true
+        uses: softprops/action-gh-release@de2c0eb89ae2a093876385947365aca7b0e5f844 # @v1
+        with:
+          name: Stockfish dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
+          tag_name: stockfish-dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
+          prerelease: true
+          files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}

AUTHORS

@@ -12,6 +12,7 @@ Hisayori Noda (nodchip)
 # All other authors of Stockfish code (in alphabetical order)
 Aditya (absimaldata)
 Adrian Petrescu (apetresc)
+Ahmed Kerimov (wcdbmv)
 Ajith Chandy Jose (ajithcj)
 Alain Savard (Rocky640)
 Alayan Feh (Alayan-stk-2)
@@ -29,6 +30,7 @@ Aram Tumanian (atumanian)
 Arjun Temurnikar
 Artem Solopiy (EntityFX)
 Auguste Pop
+Balazs Szilagyi
 Balint Pfliegel
 Ben Chaney (Chaneybenjamini)
 Ben Koshy (BKSpurgeon)
@@ -45,9 +47,12 @@ candirufish
 Chess13234
 Chris Cain (ceebo)
 clefrks
+Clemens L. (rn5f107s2)
+Cody Ho (aesrentai)
 Dale Weiler (graphitemaster)
 Daniel Axtens (daxtens)
 Daniel Dugovic (ddugovic)
+Daniel Monroe (Ergodice)
 Dan Schmidt (dfannius)
 Dariusz Orzechowski (dorzechowski)
 David (dav1312)
@@ -69,9 +74,11 @@ Fabian Beuke (madnight)
 Fabian Fichter (ianfab)
 Fanael Linithien (Fanael)
 fanon
-Fauzi Akram Dabat (FauziAkram)
+Fauzi Akram Dabat (fauzi2)
 Felix Wittmann
 gamander
+Gabriele Lombardo (gabe)
+Gahtan Nahdi
 Gary Heckman (gheckman)
 George Sobala (gsobala)
 gguliash
@@ -94,6 +101,7 @@ Jake Senne (w1wwwwww)
 Jan Ondruš (hxim)
 Jared Kish (Kurtbusch, kurt22i)
 Jarrod Torriero (DU-jdto)
+Jasper Shovelton (Beanie496)
 Jean-Francois Romang (jromang)
 Jean Gauthier (OuaisBla)
 Jekaa
@@ -178,6 +186,7 @@ Raminder Singh
 renouve
 Reuven Peleg (R-Peleg)
 Richard Lloyd (Richard-Lloyd)
+Robert Nürnberg (robertnurnberg)
 Rodrigo Exterckötter Tjäder
 Rodrigo Roim (roim)
 Ronald de Man (syzygy1, syzygy)
@@ -201,10 +210,15 @@ Stefano Cardanobile (Stefano80)
 Stefano Di Martino (StefanoD)
 Steinar Gunderson (sesse)
 Stéphane Nicolet (snicolet)
+Stephen Touset (stouset)
 Syine Mineta (MinetaS)
+Taras Vuk (TarasVuk)
 Thanar2
 thaspel
 theo77186
+TierynnB
+Ting-Hsuan Huang (fffelix-huang)
+Tobias Steinmann
 Tomasz Sobczyk (Sopel97)
 Tom Truscott
 Tom Vijlbrief (tomtor)
@@ -218,9 +232,10 @@ Vince Negri (cuddlestmonkey)
 Viren
 windfishballad
 xefoci7612
+Xiang Wang (KatyushaScarlet)
 zz4032
 
 # Additionally, we acknowledge the authors and maintainers of fishtest,
 # an amazing and essential framework for Stockfish development!
 #
-# https://github.com/glinscott/fishtest/blob/master/AUTHORS
+# https://github.com/official-stockfish/fishtest/blob/master/AUTHORS

CONTRIBUTING.md

@@ -0,0 +1,97 @@
+# Contributing to Stockfish
+
+Welcome to the Stockfish project! We are excited that you are interested in
+contributing. This document outlines the guidelines and steps to follow when
+making contributions to Stockfish.
+
+## Table of Contents
+
+- [Building Stockfish](#building-stockfish)
+- [Making Contributions](#making-contributions)
+  - [Reporting Issues](#reporting-issues)
+  - [Submitting Pull Requests](#submitting-pull-requests)
+- [Code Style](#code-style)
+- [Community and Communication](#community-and-communication)
+- [License](#license)
+
+## Building Stockfish
+
+In case you do not have a C++ compiler installed, you can follow the
+instructions from our wiki.
+
+- [Ubuntu][ubuntu-compiling-link]
+- [Windows][windows-compiling-link]
+- [macOS][macos-compiling-link]
+
+## Making Contributions
+
+### Reporting Issues
+
+If you find a bug, please open an issue on the
+[issue tracker][issue-tracker-link]. Be sure to include relevant information
+like your operating system, build environment, and a detailed description of the
+problem.
+
+_Please note that Stockfish's development is not focused on adding new features.
+Thus any issue regarding missing features will potentially be closed without
+further discussion._
+
+### Submitting Pull Requests
+
+- Functional changes need to be tested on fishtest. See
+  [Creating my First Test][creating-my-first-test] for more details.
+  The accompanying pull request should include a link to the test results and
+  the new bench.
+
+- Non-functional changes (e.g. refactoring, code style, documentation) do not
+  need to be tested on fishtest, unless they might impact performance.
+
+- Provide a clear and concise description of the changes in the pull request
+  description.
+
+_First time contributors should add their name to [AUTHORS](../AUTHORS)._
+
+_Stockfish's development is not focused on adding new features. Thus any pull
+request introducing new features will potentially be closed without further
+discussion._
+
+## Code Style
+
+Changes to Stockfish C++ code should respect our coding style defined by
+[.clang-format](.clang-format). You can format your changes by running
+`make format`. This requires clang-format version 17 to be installed on your system.
+
+## Navigate
+
+For experienced Git users who frequently use git blame, it is recommended to
+configure the blame.ignoreRevsFile setting.
+This setting is useful for excluding noisy formatting commits.
+
+```bash
+git config blame.ignoreRevsFile .git-blame-ignore-revs
+```
+
+## Community and Communication
+
+- Join the [Stockfish discord][discord-link] to discuss ideas, issues, and
+  development.
+- Participate in the [Stockfish GitHub discussions][discussions-link] for
+  broader conversations.
+
+## License
+
+By contributing to Stockfish, you agree that your contributions will be licensed
+under the GNU General Public License v3.0. See [Copying.txt][copying-link] for
+more details.
+
+Thank you for contributing to Stockfish and helping us make it even better!
+
+
+[copying-link]:           https://github.com/official-stockfish/Stockfish/blob/master/Copying.txt
+[discord-link]:           https://discord.gg/GWDRS3kU6R
+[discussions-link]:       https://github.com/official-stockfish/Stockfish/discussions/new
+[creating-my-first-test]: https://github.com/official-stockfish/fishtest/wiki/Creating-my-first-test#create-your-test
+[issue-tracker-link]:     https://github.com/official-stockfish/Stockfish/issues
+[ubuntu-compiling-link]:  https://github.com/official-stockfish/Stockfish/wiki/Developers#user-content-installing-a-compiler-1
+[windows-compiling-link]: https://github.com/official-stockfish/Stockfish/wiki/Developers#user-content-installing-a-compiler
+[macos-compiling-link]:   https://github.com/official-stockfish/Stockfish/wiki/Developers#user-content-installing-a-compiler-2

README.md

@@ -59,39 +59,10 @@ This distribution of Stockfish consists of the following files:
   * a file with the .nnue extension, storing the neural network for the NNUE
     evaluation. Binary distributions will have this file embedded.
 
-## The UCI protocol
-
-The [Universal Chess Interface][uci-link] (UCI) is a standard text-based protocol
-used to communicate with a chess engine and is the recommended way to do so for
-typical graphical user interfaces (GUI) or chess tools. Stockfish implements the
-majority of its options.
-
-Developers can see the default values for the UCI options available in Stockfish
-by typing `./stockfish uci` in a terminal, but most users should typically use a
-chess GUI to interact with Stockfish.
-
-For more information on UCI or debug commands, see our [documentation][wiki-commands-link].
-
-## Compiling Stockfish
-
-Stockfish has support for 32 or 64-bit CPUs, certain hardware instructions,
-big-endian machines such as Power PC, and other platforms.
-
-On Unix-like systems, it should be easy to compile Stockfish directly from the
-source code with the included Makefile in the folder `src`. In general, it is
-recommended to run `make help` to see a list of make targets with corresponding
-descriptions.
-
-```
-cd src
-make -j build ARCH=x86-64-modern
-```
-
-Detailed compilation instructions for all platforms can be found in our
-[documentation][wiki-compile-link].
-
 ## Contributing
 
+__See [Contributing Guide](CONTRIBUTING.md).__
+
 ### Donating hardware
 
 Improving Stockfish requires a massive amount of testing. You can donate your
@@ -114,6 +85,25 @@ Discussions about Stockfish take place these days mainly in the Stockfish
 [Discord server][discord-link]. This is also the best place to ask questions
 about the codebase and how to improve it.
 
+## Compiling Stockfish
+
+Stockfish has support for 32 or 64-bit CPUs, certain hardware instructions,
+big-endian machines such as Power PC, and other platforms.
+
+On Unix-like systems, it should be easy to compile Stockfish directly from the
+source code with the included Makefile in the folder `src`. In general, it is
+recommended to run `make help` to see a list of make targets with corresponding
+descriptions. An example suitable for most Intel and AMD chips:
+
+```
+cd src
+make -j profile-build ARCH=x86-64-avx2
+```
+
+Detailed compilation instructions for all platforms can be found in our
+[documentation][wiki-compile-link]. Our wiki also has information about
+the [UCI commands][wiki-uci-link] supported by Stockfish.
+
 ## Terms of use
 
 Stockfish is free and distributed under the
@@ -138,7 +128,7 @@ also be made available under GPL v3.
 [issue-link]:         https://github.com/official-stockfish/Stockfish/issues/new?assignees=&labels=&template=BUG-REPORT.yml
 [discussions-link]:   https://github.com/official-stockfish/Stockfish/discussions/new
 [fishtest-link]:      https://tests.stockfishchess.org/tests
-[guideline-link]:     https://github.com/glinscott/fishtest/wiki/Creating-my-first-test
+[guideline-link]:     https://github.com/official-stockfish/fishtest/wiki/Creating-my-first-test
 [license-link]:       https://github.com/official-stockfish/Stockfish/blob/master/Copying.txt
 [programming-link]:   https://www.chessprogramming.org/Main_Page
 [programmingsf-link]: https://www.chessprogramming.org/Stockfish
@@ -150,10 +140,10 @@ also be made available under GPL v3.
 [website-link]:       https://stockfishchess.org
 [website-blog-link]:  https://stockfishchess.org/blog/
 [wiki-link]:          https://github.com/official-stockfish/Stockfish/wiki
-[wiki-usage-link]:    https://github.com/official-stockfish/Stockfish/wiki/Download-and-usage
 [wiki-compile-link]:  https://github.com/official-stockfish/Stockfish/wiki/Compiling-from-source
-[wiki-commands-link]: https://github.com/official-stockfish/Stockfish/wiki/Commands
-[worker-link]:        https://github.com/glinscott/fishtest/wiki/Running-the-worker
+[wiki-uci-link]:      https://github.com/official-stockfish/Stockfish/wiki/UCI-&-Commands
+[wiki-usage-link]:    https://github.com/official-stockfish/Stockfish/wiki/Download-and-usage
+[worker-link]:        https://github.com/official-stockfish/fishtest/wiki/Running-the-worker
 
 [build-badge]:        https://img.shields.io/github/actions/workflow/status/official-stockfish/Stockfish/stockfish.yml?branch=master&style=for-the-badge&label=stockfish&logo=github
 [commits-badge]:      https://img.shields.io/github/commits-since/official-stockfish/Stockfish/latest?style=for-the-badge

Top CPU Contributors.txt

@@ -1,139 +1,146 @@
-Contributors to Fishtest with >10,000 CPU hours, as of 2023-06-20.
+Contributors to Fishtest with >10,000 CPU hours, as of 2024-02-24.
 Thank you!
 
 Username                                CPU Hours     Games played
 ------------------------------------------------------------------
-noobpwnftw                               37457426       2850540907
-technologov                              14135647        742892808
-linrock                                   4423514        303254809
+noobpwnftw                               39302472       3055513453
+technologov                              20845762        994893444
+linrock                                   8616428        560281417
 mlang                                     3026000        200065824
+okrout                                    2332151        222639518
+pemo                                      1800019         60274069
 dew                                       1689162        100033738
-okrout                                    1578136        148855886
-pemo                                      1508508         48814305
-grandphish2                               1461406         91540343
-TueRens                                   1194790         70400852
-JojoM                                      947612         61773190
+TueRens                                   1474943         75121774
+grandphish2                               1463002         91616949
+JojoM                                     1109702         72927902
+olafm                                      978631         71037944
+sebastronomy                               939955         44920556
 tvijlbrief                                 796125         51897690
-sebastronomy                               742434         38218524
+gvreuls                                    711320         49142318
 mibere                                     703840         46867607
-gvreuls                                    651026         42988582
-oz                                         543438         39314736
-cw                                         517858         34869755
+oz                                         646268         46293638
+rpngn                                      572571         38928563
+leszek                                     531858         39316505
+cw                                         518116         34894291
 fastgm                                     503862         30260818
-leszek                                     467278         33514883
-CSU_Dynasty                                464940         31177118
-ctoks                                      434416         28506889
-crunchy                                    427035         27344275
-maximmasiutin                              424795         26577722
-bcross                                     415722         29060963
-olafm                                      395922         32268020
-rpngn                                      348378         24560289
-velislav                                   342567         22138992
+CSU_Dynasty                                468784         31385034
+ctoks                                      434591         28520597
+maximmasiutin                              429983         27066286
+crunchy                                    427414         27371625
+bcross                                     415724         29061187
+velislav                                   342588         22140902
+mgrabiak                                   338763         23999170
 Fisherman                                  327231         21829379
-mgrabiak                                   300612         20608380
+robal                                      299836         20213182
 Dantist                                    296386         18031762
-nordlandia                                 246201         16189678
-robal                                      241300         15656382
+ncfish1                                    267604         17881149
+nordlandia                                 249322         16420192
 marrco                                     234581         17714473
-ncfish1                                    227517         15233777
+tolkki963                                  233490         19773930
 glinscott                                  208125         13277240
 drabel                                     204167         13930674
 mhoram                                     202894         12601997
 bking_US                                   198894         11876016
+Calis007                                   188631         12795784
 Thanar                                     179852         12365359
+Fifis                                      176209         10638245
 vdv                                        175544          9904472
 spams                                      157128         10319326
+DesolatedDodo                              156659         10210328
+armo9494                                   155355         10566898
 sqrt2                                      147963          9724586
-DesolatedDodo                              146350          9536172
-Calis007                                   143165          9478764
-vdbergh                                    138650          9064413
+jcAEie                                     140086         10603658
+vdbergh                                    139746          9172061
 CoffeeOne                                  137100          5024116
-armo9494                                   136191          9460264
 malala                                     136182          8002293
 xoto                                       133759          9159372
 davar                                      129023          8376525
 DMBK                                       122960          8980062
 dsmith                                     122059          7570238
+javran                                     121564         10144656
 amicic                                     119661          7938029
+sschnee                                    118107          7389266
+Wolfgang                                   114616          8070494
 Data                                       113305          8220352
 BrunoBanani                                112960          7436849
+Wencey                                     111502          5991676
+cuistot                                    108503          7006992
 CypressChess                               108331          7759788
 skiminki                                   107583          7218170
-jcAEie                                     105675          8238962
 MaZePallas                                 102823          6633619
 sterni1971                                 100532          5880772
 sunu                                       100167          7040199
 zeryl                                       99331          6221261
-thirdlife                                   99124          2242380
+thirdlife                                   99156          2245320
 ElbertoOne                                  99028          7023771
-cuistot                                     98853          6069816
+Dubslow                                     98600          6903242
+markkulix                                   97010          7643900
 bigpen0r                                    94809          6529203
 brabos                                      92118          6186135
-Wolfgang                                    91939          6105872
+Maxim                                       90818          3283364
 psk                                         89957          5984901
-sschnee                                     88235          5268000
+megaman7de                                  88822          6052132
 racerschmacer                               85805          6122790
-Fifis                                       85722          5709729
-Dubslow                                     84986          6042456
+maposora                                    85710          7778146
 Vizvezdenec                                 83761          5344740
 0x3C33                                      82614          5271253
 BRAVONE                                     81239          5054681
 nssy                                        76497          5259388
 jromang                                     76106          5236025
 teddybaer                                   75125          5407666
-tolkki963                                   74762          5149662
-megaman7de                                  74351          4940352
-Wencey                                      74181          4711488
 Pking_cda                                   73776          5293873
-yurikvelo                                   73150          5004382
-markkulix                                   72607          5304642
+yurikvelo                                   73516          5036928
+MarcusTullius                               71053          4803477
 Bobo1239                                    70579          4794999
 solarlight                                  70517          5028306
 dv8silencer                                 70287          3883992
+Spprtr                                      69646          4806763
+Mineta                                      66325          4537742
 manap                                       66273          4121774
+szupaw                                      65468          5669742
 tinker                                      64333          4268790
 qurashee                                    61208          3429862
-Mineta                                      59357          4418202
-Spprtr                                      58723          3911011
-AGI                                         58147          4325994
+woutboat                                    59496          4906352
+AGI                                         58195          4329580
 robnjr                                      57262          4053117
 Freja                                       56938          3733019
 MaxKlaxxMiner                               56879          3423958
-MarcusTullius                               56746          3762951
 ttruscott                                   56010          3680085
 rkl                                         55132          4164467
+jmdana                                      54697          4012593
 renouve                                     53811          3501516
-javran                                      53785          4627608
+notchris                                    52433          4044590
 finfish                                     51360          3370515
 eva42                                       51272          3599691
 eastorwest                                  51117          3454811
+Goatminola                                  51004          4432492
 rap                                         49985          3219146
 pb00067                                     49733          3298934
+GPUex                                       48686          3684998
 OuaisBla                                    48626          3445134
 ronaldjerum                                 47654          3240695
 biffhero                                    46564          3111352
+oryx                                        45533          3539290
 VoyagerOne                                  45476          3452465
-jmdana                                      44893          3065205
-maposora                                    44597          4039578
-oryx                                        44570          3454238
 speedycpu                                   43842          3003273
 jbwiebe                                     43305          2805433
-GPUex                                       42378          3133332
 Antihistamine                               41788          2761312
 mhunt                                       41735          2691355
 homyur                                      39893          2850481
 gri                                         39871          2515779
 Garf                                        37741          2999686
 SC                                          37299          2731694
+Sylvain27                                   36520          1467082
 csnodgrass                                  36207          2688994
+Gaster319                                   35655          3149442
 strelock                                    34716          2074055
-szupaw                                      34102          2880346
 EthanOConnor                                33370          2090311
 slakovv                                     32915          2021889
+gopeto                                      31884          2076712
 Gelma                                       31771          1551204
-gopeto                                      31671          2060990
 kdave                                       31157          2198362
 manapbk                                     30987          1810399
+ZacHFX                                      30551          2238078
 Prcuvu                                      30377          2170122
 anst                                        30301          2190091
 jkiiski                                     30136          1904470
@@ -142,27 +149,31 @@ hyperbolic.tom                              29840          2017394
 chuckstablers                               29659          2093438
 Pyafue                                      29650          1902349
 belzedar94                                  28846          1811530
+votoanthuan                                 27978          2285818
+shawnxu                                     27438          2465810
 chriswk                                     26902          1868317
 xwziegtm                                    26897          2124586
 achambord                                   26582          1767323
 Patrick_G                                   26276          1801617
 yorkman                                     26193          1992080
-Ulysses                                     25288          1689730
+Ulysses                                     25397          1701264
+Jopo12321                                   25227          1652482
 SFTUser                                     25182          1675689
-nabildanial                                 24942          1519409
+nabildanial                                 25068          1531665
 Sharaf_DG                                   24765          1786697
-Maxim                                       24705          1502062
 rodneyc                                     24376          1416402
+jsys14                                      24297          1721230
 agg177                                      23890          1395014
-Goatminola                                  23763          1956036
-Ente                                        23639          1671638
-Jopo12321                                   23467          1483172
+srowen                                      23842          1342508
+Ente                                        23752          1678188
+jojo2357                                    23479          2061238
 JanErik                                     23408          1703875
 Isidor                                      23388          1680691
 Norabor                                     23371          1603244
 cisco2015                                   22920          1763301
-jsys14                                      22824          1591906
 Zirie                                       22542          1472937
+Nullvalue                                   22490          1970374
+AndreasKrug                                 22485          1769491
 team-oh                                     22272          1636708
 Roady                                       22220          1465606
 MazeOfGalious                               21978          1629593
@@ -173,79 +184,83 @@ dex                                         21612          1467203
 nesoneg                                     21494          1463031
 user213718                                  21454          1404128
 sphinx                                      21211          1384728
-AndreasKrug                                 21097          1634811
+qoo_charly_cai                              21135          1514907
 jjoshua2                                    21001          1423089
 Zake9298                                    20938          1565848
 horst.prack                                 20878          1465656
 0xB00B1ES                                   20590          1208666
+Serpensin                                   20487          1729674
+Dinde                                       20440          1292390
 j3corre                                     20405           941444
 Adrian.Schmidt123                           20316          1281436
 wei                                         19973          1745989
-notchris                                    19958          1800128
-Serpensin                                   19840          1697528
-Gaster319                                   19712          1677310
 fishtester                                  19617          1257388
 rstoesser                                   19569          1293588
 eudhan                                      19274          1283717
-votoanthuan                                 19108          1609992
 vulcan                                      18871          1729392
 Karpovbot                                   18766          1053178
-qoo_charly_cai                              18543          1284937
+WoodMan777                                  18556          1628264
 jundery                                     18445          1115855
 ville                                       17883          1384026
 chris                                       17698          1487385
 purplefishies                               17595          1092533
 dju                                         17414           981289
+ols                                         17291          1042003
 iisiraider                                  17275          1049015
+Skiff84                                     17111           950248
 DragonLord                                  17014          1162790
 redstone59                                  16842          1461780
-Alb11747                                    16787          1213926
+Karby                                       16839          1010124
+Alb11747                                    16787          1213990
+pirt                                        16493          1237199
+Naven94                                     16414           951718
+wizardassassin                              16392          1148672
 IgorLeMasson                                16064          1147232
-Karby                                       15982           979610
 scuzzi                                      15757           968735
 ako027ako                                   15671          1173203
 Nikolay.IT                                  15154          1068349
 Andrew Grant                                15114           895539
-Naven94                                     15054           834762
 OssumOpossum                                14857          1007129
-ZacHFX                                      14783          1021842
+LunaticBFF57                                14525          1190310
 enedene                                     14476           905279
+IslandLambda                                14393           958196
 bpfliegel                                   14233           882523
+YELNAMRON                                   14230          1128094
 mpx86                                       14019           759568
 jpulman                                     13982           870599
-Skiff84                                     13826           721996
+getraideBFF                                 13871          1172846
+Nesa92                                      13806          1116101
 crocogoat                                   13803          1117422
-Nesa92                                      13786          1114691
 joster                                      13710           946160
 mbeier                                      13650          1044928
 Hjax                                        13535           915487
-Nullvalue                                   13468          1140498
 Dark_wizzie                                 13422          1007152
 Rudolphous                                  13244           883140
-pirt                                        13100          1009897
 Machariel                                   13010           863104
 infinigon                                   12991           943216
 mabichito                                   12903           749391
 thijsk                                      12886           722107
 AdrianSA                                    12860           804972
 Flopzee                                     12698           894821
+mschmidt                                    12644           863193
 korposzczur                                 12606           838168
+tsim67                                      12570           890180
+Jackfish                                    12553           836958
 fatmurphy                                   12547           853210
+Oakwen                                      12503           853105
 SapphireBrand                               12416           969604
-Oakwen                                      12399           844109
 deflectooor                                 12386           579392
 modolief                                    12386           896470
+TataneSan                                   12358           609332
 Farseer                                     12249           694108
-Jackfish                                    12213           805008
 pgontarz                                    12151           848794
 dbernier                                    12103           860824
-getraideBFF                                 12072          1024966
+FormazChar                                  11989           907809
 stocky                                      11954           699440
-mschmidt                                    11941           803401
-MooTheCow                                   11870           773598
-FormazChar                                  11766           885707
+somethingintheshadows                       11940           989472
+MooTheCow                                   11892           776126
+3cho                                        11842          1036786
 whelanh                                     11557           245188
-3cho                                        11494          1031076
 infinity                                    11470           727027
 aga                                         11412           695127
 torbjo                                      11395           729145
@@ -253,15 +268,19 @@ Thomas A. Anderson                          11372           732094
 savage84                                    11358           670860
 d64                                         11263           789184
 ali-al-zhrani                               11245           779246
+ckaz                                        11170           680866
 snicolet                                    11106           869170
 dapper                                      11032           771402
-ols                                         10947           624903
-Karmatron                                   10828           677458
+Ethnikoi                                    10993           945906
+Snuuka                                      10938           435504
+Karmatron                                   10859           678058
 basepi                                      10637           744851
+jibarbosa                                   10628           857100
 Cubox                                       10621           826448
+mecevdimitar                                10609           787318
 michaelrpg                                  10509           739239
+Def9Infinity                                10427           686978
 OIVAS7572                                   10420           995586
-jojo2357                                    10419           929708
-WoodMan777                                  10380           873720
+wxt9861                                     10412          1013864
 Garruk                                      10365           706465
 dzjp                                        10343           732529

scripts/get_native_properties.sh

@@ -0,0 +1,120 @@
+#!/bin/sh
+
+#
+# Returns properties of the native system.
+# best architecture as supported by the CPU
+# filename of the best binary uploaded as an artifact during CI
+#
+
+# Check if all the given flags are present in the CPU flags list
+check_flags() {
+  for flag; do
+    printf '%s\n' "$flags" | grep -q -w "$flag" || return 1
+  done
+}
+
+# Set the CPU flags list
+# remove underscores and points from flags, e.g. gcc uses avx512vnni, while some cpuinfo can have avx512_vnni, some systems use sse4_1 others sse4.1
+get_flags() {
+  flags=$(awk '/^flags[ \t]*:|^Features[ \t]*:/{gsub(/^flags[ \t]*:[ \t]*|^Features[ \t]*:[ \t]*|[_.]/, ""); line=$0} END{print line}' /proc/cpuinfo)
+}
+
+# Check for gcc march "znver1" or "znver2" https://en.wikichip.org/wiki/amd/cpuid
+check_znver_1_2() {
+  vendor_id=$(awk '/^vendor_id/{print $3; exit}' /proc/cpuinfo)
+  cpu_family=$(awk '/^cpu family/{print $4; exit}' /proc/cpuinfo)
+  [ "$vendor_id" = "AuthenticAMD" ] && [ "$cpu_family" = "23" ] && znver_1_2=true
+}
+
+# Set the file CPU x86_64 architecture
+set_arch_x86_64() {
+  if check_flags 'avx512vnni' 'avx512dq' 'avx512f' 'avx512bw' 'avx512vl'; then
+    true_arch='x86-64-vnni256'
+  elif check_flags 'avx512f' 'avx512bw'; then
+    true_arch='x86-64-avx512'
+  elif [ -z "${znver_1_2+1}" ] && check_flags 'bmi2'; then
+    true_arch='x86-64-bmi2'
+  elif check_flags 'avx2'; then
+    true_arch='x86-64-avx2'
+  elif check_flags 'sse41' && check_flags 'popcnt'; then
+    true_arch='x86-64-sse41-popcnt'
+  else
+    true_arch='x86-64'
+  fi
+}
+
+# Check the system type
+uname_s=$(uname -s)
+uname_m=$(uname -m)
+case $uname_s in
+  'Darwin') # Mac OSX system
+    case $uname_m in
+      'arm64')
+        true_arch='apple-silicon'
+        file_arch='x86-64-sse41-popcnt' # Supported by Rosetta 2
+        ;;
+      'x86_64')
+        flags=$(sysctl -n machdep.cpu.features machdep.cpu.leaf7_features | tr '\n' ' ' | tr '[:upper:]' '[:lower:]' | tr -d '_.')
+        set_arch_x86_64
+        if [ "$true_arch" = 'x86-64-vnni256' ] || [ "$true_arch" = 'x86-64-avx512' ]; then
+           file_arch='x86-64-bmi2'
+        fi
+        ;;
+    esac
+    file_os='macos'
+    file_ext='tar'
+    ;;
+  'Linux') # Linux system
+    get_flags
+    case $uname_m in
+      'x86_64')
+        file_os='ubuntu'
+        check_znver_1_2
+        set_arch_x86_64
+        ;;
+      'i686')
+        file_os='ubuntu'
+        true_arch='x86-32'
+        ;;
+      'aarch64')
+        file_os='android'
+        true_arch='armv8'
+        if check_flags 'asimddp'; then
+          true_arch="$true_arch-dotprod"
+        fi
+        ;;
+      'armv7'*)
+        file_os='android'
+        true_arch='armv7'
+        if check_flags 'neon'; then
+          true_arch="$true_arch-neon"
+        fi
+        ;;
+      *) # Unsupported machine type, exit with error
+        printf 'Unsupported machine type: %s\n' "$uname_m"
+        exit 1
+        ;;
+    esac
+    file_ext='tar'
+    ;;
+  'CYGWIN'*|'MINGW'*|'MSYS'*) # Windows system with POSIX compatibility layer
+    get_flags
+    check_znver_1_2
+    set_arch_x86_64
+    file_os='windows'
+    file_ext='zip'
+    ;;
+  *)
+    # Unknown system type, exit with error
+    printf 'Unsupported system type: %s\n' "$uname_s"
+    exit 1
+    ;;
+esac
+
+if [ -z "$file_arch" ]; then
+  file_arch=$true_arch
+fi
+
+file_name="stockfish-$file_os-$file_arch.$file_ext"
+
+printf '%s %s\n' "$true_arch" "$file_name"

src/Makefile

@@ -1,5 +1,5 @@
 # Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-# Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+# Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 #
 # Stockfish is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,9 +20,9 @@
 ### ==========================================================================
 
 ### Establish the operating system name
-KERNEL = $(shell uname -s)
+KERNEL := $(shell uname -s)
 ifeq ($(KERNEL),Linux)
-	OS = $(shell uname -o)
+	OS := $(shell uname -o)
 endif
 
 ### Target Windows OS
@@ -33,7 +33,7 @@ ifeq ($(OS),Windows_NT)
 else ifeq ($(COMP),mingw)
 	target_windows = yes
 	ifeq ($(WINE_PATH),)
-		WINE_PATH = $(shell which wine)
+		WINE_PATH := $(shell which wine)
 	endif
 endif
 
@@ -49,18 +49,22 @@ PREFIX = /usr/local
 BINDIR = $(PREFIX)/bin
 
 ### Built-in benchmark for pgo-builds
-ifeq ($(SDE_PATH),)
-	PGOBENCH = $(WINE_PATH) ./$(EXE) bench
-else
-	PGOBENCH = $(SDE_PATH) -- $(WINE_PATH) ./$(EXE) bench
-endif
+PGOBENCH = $(WINE_PATH) ./$(EXE) bench
 
 ### Source and object files
-SRCS = benchmark.cpp bitbase.cpp bitboard.cpp endgame.cpp evaluate.cpp main.cpp \
-	material.cpp misc.cpp movegen.cpp movepick.cpp pawns.cpp position.cpp psqt.cpp \
+SRCS = benchmark.cpp bitboard.cpp evaluate.cpp main.cpp \
+	misc.cpp movegen.cpp movepick.cpp position.cpp \
 	search.cpp thread.cpp timeman.cpp tt.cpp uci.cpp ucioption.cpp tune.cpp syzygy/tbprobe.cpp \
 	nnue/evaluate_nnue.cpp nnue/features/half_ka_v2_hm.cpp
 
+HEADERS = benchmark.h bitboard.h evaluate.h misc.h movegen.h movepick.h \
+		nnue/evaluate_nnue.h nnue/features/half_ka_v2_hm.h nnue/layers/affine_transform.h \
+		nnue/layers/affine_transform_sparse_input.h nnue/layers/clipped_relu.h nnue/layers/simd.h \
+		nnue/layers/sqr_clipped_relu.h nnue/nnue_accumulator.h nnue/nnue_architecture.h \
+		nnue/nnue_common.h nnue/nnue_feature_transformer.h position.h \
+		search.h syzygy/tbprobe.h thread.h thread_win32_osx.h timeman.h \
+		tt.h tune.h types.h uci.h ucioption.h perft.h
+
 OBJS = $(notdir $(SRCS:.cpp=.o))
 
 VPATH = syzygy:nnue:nnue/features
@@ -108,16 +112,20 @@ VPATH = syzygy:nnue:nnue/features
 ### 2.1. General and architecture defaults
 
 ifeq ($(ARCH),)
-   ARCH = x86-64-modern
-   help_skip_sanity = yes
+   ARCH = native
 endif
+
+ifeq ($(ARCH), native)
+   override ARCH := $(shell $(SHELL) ../scripts/get_native_properties.sh | cut -d " " -f 1)
+endif
+
 # explicitly check for the list of supported architectures (as listed with make help),
 # the user can override with `make ARCH=x86-32-vnni256 SUPPORTED_ARCH=true`
 ifeq ($(ARCH), $(filter $(ARCH), \
                  x86-64-vnni512 x86-64-vnni256 x86-64-avx512 x86-64-avxvnni x86-64-bmi2 \
                  x86-64-avx2 x86-64-sse41-popcnt x86-64-modern x86-64-ssse3 x86-64-sse3-popcnt \
                  x86-64 x86-32-sse41-popcnt x86-32-sse2 x86-32 ppc-64 ppc-32 e2k \
-                 armv7 armv7-neon armv8 armv8-dotprod apple-silicon general-64 general-32 riscv64))
+                 armv7 armv7-neon armv8 armv8-dotprod apple-silicon general-64 general-32 riscv64 loongarch64))
    SUPPORTED_ARCH=true
 else
    SUPPORTED_ARCH=false
@@ -145,6 +153,12 @@ dotprod = no
 arm_version = 0
 STRIP = strip
 
+ifneq ($(shell which clang-format-17 2> /dev/null),)
+	CLANG-FORMAT = clang-format-17
+else
+	CLANG-FORMAT = clang-format
+endif
+
 ### 2.2 Architecture specific
 
 ifeq ($(findstring x86,$(ARCH)),x86)
@@ -193,6 +207,8 @@ ifeq ($(findstring -sse41,$(ARCH)),-sse41)
 endif
 
 ifeq ($(findstring -modern,$(ARCH)),-modern)
+        $(warning *** ARCH=$(ARCH) is deprecated, defaulting to ARCH=x86-64-sse41-popcnt. Execute `make help` for a list of available architectures. ***)
+        $(shell sleep 5)
 	popcnt = yes
 	sse = yes
 	sse2 = yes
@@ -353,6 +369,10 @@ endif
 ifeq ($(ARCH),riscv64)
 	arch = riscv64
 endif
+
+ifeq ($(ARCH),loongarch64)
+	arch = loongarch64
+endif
 endif
 
 
@@ -388,6 +408,8 @@ ifeq ($(COMP),gcc)
 		ifeq ($(ARCH),riscv64)
 			CXXFLAGS += -latomic
 		endif
+	else ifeq ($(ARCH),loongarch64)
+		CXXFLAGS += -latomic
 	else
 		CXXFLAGS += -m$(bits)
 		LDFLAGS += -m$(bits)
@@ -458,6 +480,8 @@ ifeq ($(COMP),clang)
 		ifeq ($(ARCH),riscv64)
 			CXXFLAGS += -latomic
 		endif
+	else ifeq ($(ARCH),loongarch64)
+		CXXFLAGS += -latomic
 	else
 		CXXFLAGS += -m$(bits)
 		LDFLAGS += -m$(bits)
@@ -497,6 +521,14 @@ ifeq ($(COMP),ndk)
 			STRIP=llvm-strip
 		endif
 	endif
+	ifeq ($(arch),x86_64)
+		CXX=x86_64-linux-android21-clang++
+		ifneq ($(shell which x86_64-linux-android-strip 2>/dev/null),)
+			STRIP=x86_64-linux-android-strip
+		else
+			STRIP=llvm-strip
+		endif
+	endif
 	LDFLAGS += -static-libstdc++ -pie -lm -latomic
 endif
 
@@ -526,8 +558,8 @@ endif
 
 ### Sometimes gcc is really clang
 ifeq ($(COMP),gcc)
-	gccversion = $(shell $(CXX) --version 2>/dev/null)
-	gccisclang = $(findstring clang,$(gccversion))
+	gccversion := $(shell $(CXX) --version 2>/dev/null)
+	gccisclang := $(findstring clang,$(gccversion))
 	ifneq ($(gccisclang),)
 		profile_make = clang-profile-make
 		profile_use = clang-profile-use
@@ -564,7 +596,7 @@ endif
 ### 3.3 Optimization
 ifeq ($(optimize),yes)
 
-	CXXFLAGS += -O3
+	CXXFLAGS += -O3 -funroll-loops
 
 	ifeq ($(comp),gcc)
 		ifeq ($(OS), Android)
@@ -585,7 +617,7 @@ ifeq ($(optimize),yes)
 	endif
 
 	ifeq ($(comp),clang)
-		clangmajorversion = $(shell $(CXX) -dumpversion 2>/dev/null | cut -f1 -d.)
+		clangmajorversion := $(shell $(CXX) -dumpversion 2>/dev/null | cut -f1 -d.)
 		ifeq ($(shell expr $(clangmajorversion) \< 16),1)
 			CXXFLAGS += -fexperimental-new-pass-manager
 		endif
@@ -672,7 +704,6 @@ ifeq ($(sse2),yes)
 endif
 
 ifeq ($(mmx),yes)
-	CXXFLAGS += -DUSE_MMX
 	ifeq ($(comp),$(filter $(comp),gcc clang mingw icx))
 		CXXFLAGS += -mmmx
 	endif
@@ -701,19 +732,24 @@ ifeq ($(pext),yes)
 	endif
 endif
 
-### 3.7.1 Try to include git commit sha for versioning
-GIT_SHA = $(shell git rev-parse HEAD 2>/dev/null | cut -c 1-8)
+### 3.8.1 Try to include git commit sha for versioning
+GIT_SHA := $(shell git rev-parse HEAD 2>/dev/null | cut -c 1-8)
 ifneq ($(GIT_SHA), )
 	CXXFLAGS += -DGIT_SHA=$(GIT_SHA)
 endif
 
-### 3.7.2 Try to include git commit date for versioning
-GIT_DATE = $(shell git show -s --date=format:'%Y%m%d' --format=%cd HEAD 2>/dev/null)
+### 3.8.2 Try to include git commit date for versioning
+GIT_DATE := $(shell git show -s --date=format:'%Y%m%d' --format=%cd HEAD 2>/dev/null)
 ifneq ($(GIT_DATE), )
 	CXXFLAGS += -DGIT_DATE=$(GIT_DATE)
 endif
 
-### 3.8 Link Time Optimization
+### 3.8.3 Try to include architecture
+ifneq ($(ARCH), )
+	CXXFLAGS += -DARCH=$(ARCH)
+endif
+
+### 3.9 Link Time Optimization
 ### This is a mix of compile and link time options because the lto link phase
 ### needs access to the optimization flags.
 ifeq ($(optimize),yes)
@@ -748,7 +784,7 @@ ifeq ($(debug), no)
 endif
 endif
 
-### 3.9 Android 5 can only run position independent executables. Note that this
+### 3.10 Android 5 can only run position independent executables. Note that this
 ### breaks Android 4.0 and earlier.
 ifeq ($(OS), Android)
 	CXXFLAGS += -fPIE
@@ -759,25 +795,25 @@ endif
 ### Section 4. Public Targets
 ### ==========================================================================
 
-
 help:
 	@echo ""
 	@echo "To compile stockfish, type: "
 	@echo ""
-	@echo "make target ARCH=arch [COMP=compiler] [COMPCXX=cxx]"
+	@echo "make -j target [ARCH=arch] [COMP=compiler] [COMPCXX=cxx]"
 	@echo ""
 	@echo "Supported targets:"
 	@echo ""
 	@echo "help                    > Display architecture details"
 	@echo "profile-build           > standard build with profile-guided optimization"
 	@echo "build                   > skip profile-guided optimization"
-	@echo "net                     > Download the default nnue net"
+	@echo "net                     > Download the default nnue nets"
 	@echo "strip                   > Strip executable"
 	@echo "install                 > Install executable"
 	@echo "clean                   > Clean up"
 	@echo ""
 	@echo "Supported archs:"
 	@echo ""
+	@echo "native                  > select the best architecture for the host processor (default)"
 	@echo "x86-64-vnni512          > x86 64-bit with vnni 512bit support"
 	@echo "x86-64-vnni256          > x86 64-bit with vnni 512bit support, limit operands to 256bit wide"
 	@echo "x86-64-avx512           > x86 64-bit with avx512 support"
@@ -785,13 +821,13 @@ help:
 	@echo "x86-64-bmi2             > x86 64-bit with bmi2 support"
 	@echo "x86-64-avx2             > x86 64-bit with avx2 support"
 	@echo "x86-64-sse41-popcnt     > x86 64-bit with sse41 and popcnt support"
-	@echo "x86-64-modern           > common modern CPU, currently x86-64-sse41-popcnt"
+	@echo "x86-64-modern           > deprecated, currently x86-64-sse41-popcnt"
 	@echo "x86-64-ssse3            > x86 64-bit with ssse3 support"
-	@echo "x86-64-sse3-popcnt      > x86 64-bit with sse3 and popcnt support"
+	@echo "x86-64-sse3-popcnt      > x86 64-bit with sse3 compile and popcnt support"
 	@echo "x86-64                  > x86 64-bit generic (with sse2 support)"
 	@echo "x86-32-sse41-popcnt     > x86 32-bit with sse41 and popcnt support"
 	@echo "x86-32-sse2             > x86 32-bit with sse2 support"
-	@echo "x86-32                  > x86 32-bit generic (with mmx and sse support)"
+	@echo "x86-32                  > x86 32-bit generic (with mmx compile support)"
 	@echo "ppc-64                  > PPC 64-bit"
 	@echo "ppc-32                  > PPC 32-bit"
 	@echo "armv7                   > ARMv7 32-bit"
@@ -803,11 +839,12 @@ help:
 	@echo "general-64              > unspecified 64-bit"
 	@echo "general-32              > unspecified 32-bit"
 	@echo "riscv64                 > RISC-V 64-bit"
+	@echo "loongarch64             > LoongArch 64-bit"
 	@echo ""
 	@echo "Supported compilers:"
 	@echo ""
-	@echo "gcc                     > Gnu compiler (default)"
-	@echo "mingw                   > Gnu compiler with MinGW under Windows"
+	@echo "gcc                     > GNU compiler (default)"
+	@echo "mingw                   > GNU compiler with MinGW under Windows"
 	@echo "clang                   > LLVM Clang compiler"
 	@echo "icx                     > Intel oneAPI DPC++/C++ Compiler"
 	@echo "ndk                     > Google NDK to cross-compile for Android"
@@ -815,30 +852,30 @@ help:
 	@echo "Simple examples. If you don't know what to do, you likely want to run one of: "
 	@echo ""
 	@echo "make -j profile-build ARCH=x86-64-avx2    # typically a fast compile for common systems "
-	@echo "make -j profile-build ARCH=x86-64-modern  # A more portable compile for 64-bit systems "
+	@echo "make -j profile-build ARCH=x86-64-sse41-popcnt  # A more portable compile for 64-bit systems "
 	@echo "make -j profile-build ARCH=x86-64         # A portable compile for 64-bit systems "
 	@echo ""
 	@echo "Advanced examples, for experienced users: "
 	@echo ""
-	@echo "make -j profile-build ARCH=x86-64-bmi2"
-	@echo "make -j profile-build ARCH=x86-64-bmi2 COMP=gcc COMPCXX=g++-9.0"
+	@echo "make -j profile-build ARCH=x86-64-avxvnni"
+	@echo "make -j profile-build ARCH=x86-64-avxvnni COMP=gcc COMPCXX=g++-12.0"
 	@echo "make -j build ARCH=x86-64-ssse3 COMP=clang"
 	@echo ""
-	@echo "-------------------------------"
-ifeq ($(SUPPORTED_ARCH)$(help_skip_sanity), true)
-	@echo "The selected architecture $(ARCH) will enable the following configuration: "
-	@$(MAKE) ARCH=$(ARCH) COMP=$(COMP) config-sanity
-else
+ifneq ($(SUPPORTED_ARCH), true)
 	@echo "Specify a supported architecture with the ARCH option for more details"
 	@echo ""
 endif
 
 
-.PHONY: help build profile-build strip install clean net objclean profileclean \
-	config-sanity \
+.PHONY: help analyze build profile-build strip install clean net \
+	objclean profileclean config-sanity \
 	icx-profile-use icx-profile-make \
 	gcc-profile-use gcc-profile-make \
-	clang-profile-use clang-profile-make FORCE
+	clang-profile-use clang-profile-make FORCE \
+	format analyze
+
+analyze: net config-sanity objclean
+	$(MAKE) -k ARCH=$(ARCH) COMP=$(COMP) $(OBJS)
 
 build: net config-sanity
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) all
@@ -849,7 +886,8 @@ profile-build: net config-sanity objclean profileclean
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) $(profile_make)
 	@echo ""
 	@echo "Step 2/4. Running benchmark for pgo-build ..."
-	$(PGOBENCH) 2>&1 | tail -n 4
+	$(PGOBENCH) > PGOBENCH.out 2>&1
+	tail -n 4 PGOBENCH.out
 	@echo ""
 	@echo "Step 3/4. Building optimized executable ..."
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) objclean
@@ -870,42 +908,6 @@ install:
 clean: objclean profileclean
 	@rm -f .depend *~ core
 
-# evaluation network (nnue)
-net:
-	$(eval nnuenet := $(shell grep EvalFileDefaultName evaluate.h | grep define | sed 's/.*\(nn-[a-z0-9]\{12\}.nnue\).*/\1/'))
-	@echo "Default net: $(nnuenet)"
-	$(eval nnuedownloadurl1 := https://tests.stockfishchess.org/api/nn/$(nnuenet))
-	$(eval nnuedownloadurl2 := https://github.com/official-stockfish/networks/raw/master/$(nnuenet))
-	$(eval curl_or_wget := $(shell if hash curl 2>/dev/null; then echo "curl -skL"; elif hash wget 2>/dev/null; then echo "wget -qO-"; fi))
-	@if [ "x$(curl_or_wget)" = "x" ]; then \
-	    echo "Neither curl nor wget is installed. Install one of these tools unless the net has been downloaded manually"; \
-        fi
-	$(eval shasum_command := $(shell if hash shasum 2>/dev/null; then echo "shasum -a 256 "; elif hash sha256sum 2>/dev/null; then echo "sha256sum "; fi))
-	@if [ "x$(shasum_command)" = "x" ]; then \
-            echo "shasum / sha256sum not found, skipping net validation"; \
-        fi
-	@for nnuedownloadurl in "$(nnuedownloadurl1)" "$(nnuedownloadurl2)"; do \
-	   if test -f "$(nnuenet)"; then \
-	      echo "$(nnuenet) available."; \
-	   else \
-	      if [ "x$(curl_or_wget)" != "x" ]; then \
-                 echo "Downloading $${nnuedownloadurl}"; $(curl_or_wget) $${nnuedownloadurl} > $(nnuenet);\
-              else \
-                 echo "No net found and download not possible"; exit 1;\
-	      fi; \
-	   fi; \
-	   if [ "x$(shasum_command)" != "x" ]; then \
-	      if [ "$(nnuenet)" != "nn-"`$(shasum_command) $(nnuenet) | cut -c1-12`".nnue" ]; then \
-	         echo "Removing failed download"; rm -f $(nnuenet); \
-	      else \
-	         echo "Network validated"; break; \
-	      fi; \
-	   fi; \
-	done
-	@if ! test -f "$(nnuenet)"; then \
-	    echo "Failed to download $(nnuenet)."; \
-	fi
-
 # clean binaries and objects
 objclean:
 	@rm -f stockfish stockfish.exe *.o ./syzygy/*.o ./nnue/*.o ./nnue/features/*.o
@@ -913,13 +915,71 @@ objclean:
 # clean auxiliary profiling files
 profileclean:
 	@rm -rf profdir
-	@rm -f bench.txt *.gcda *.gcno ./syzygy/*.gcda ./nnue/*.gcda ./nnue/features/*.gcda *.s
+	@rm -f bench.txt *.gcda *.gcno ./syzygy/*.gcda ./nnue/*.gcda ./nnue/features/*.gcda *.s PGOBENCH.out
 	@rm -f stockfish.profdata *.profraw
 	@rm -f stockfish.*args*
 	@rm -f stockfish.*lt*
 	@rm -f stockfish.res
 	@rm -f ./-lstdc++.res
 
+define fetch_network
+	@echo "Default net: $(nnuenet)"
+	@if [ "x$(curl_or_wget)" = "x" ]; then \
+		echo "Neither curl nor wget is installed. Install one of these tools unless the net has been downloaded manually"; \
+	fi
+	@if [ "x$(shasum_command)" = "x" ]; then \
+		echo "shasum / sha256sum not found, skipping net validation"; \
+	elif test -f "$(nnuenet)"; then \
+		if [ "$(nnuenet)" != "nn-"`$(shasum_command) $(nnuenet) | cut -c1-12`".nnue" ]; then \
+			echo "Removing invalid network"; rm -f $(nnuenet); \
+		fi; \
+	fi;
+	@for nnuedownloadurl in "$(nnuedownloadurl1)" "$(nnuedownloadurl2)"; do \
+		if test -f "$(nnuenet)"; then \
+			echo "$(nnuenet) available : OK"; break; \
+		else \
+			if [ "x$(curl_or_wget)" != "x" ]; then \
+				echo "Downloading $${nnuedownloadurl}"; $(curl_or_wget) $${nnuedownloadurl} > $(nnuenet);\
+			else \
+				echo "No net found and download not possible"; exit 1;\
+			fi; \
+		fi; \
+		if [ "x$(shasum_command)" != "x" ]; then \
+			if [ "$(nnuenet)" != "nn-"`$(shasum_command) $(nnuenet) | cut -c1-12`".nnue" ]; then \
+				echo "Removing failed download"; rm -f $(nnuenet); \
+			fi; \
+		fi; \
+	done
+	@if ! test -f "$(nnuenet)"; then \
+		echo "Failed to download $(nnuenet)."; \
+	fi;
+	@if [ "x$(shasum_command)" != "x" ]; then \
+		if [ "$(nnuenet)" = "nn-"`$(shasum_command) $(nnuenet) | cut -c1-12`".nnue" ]; then \
+			echo "Network validated"; break; \
+		fi; \
+	fi;
+endef
+
+# set up shell variables for the net stuff
+define netvariables
+$(eval nnuenet := $(shell grep $(1) evaluate.h | grep define | sed 's/.*\(nn-[a-z0-9]\{12\}.nnue\).*/\1/'))
+$(eval nnuedownloadurl1 := https://tests.stockfishchess.org/api/nn/$(nnuenet))
+$(eval nnuedownloadurl2 := https://github.com/official-stockfish/networks/raw/master/$(nnuenet))
+$(eval curl_or_wget := $(shell if hash curl 2>/dev/null; then echo "curl -skL"; elif hash wget 2>/dev/null; then echo "wget -qO-"; fi))
+$(eval shasum_command := $(shell if hash shasum 2>/dev/null; then echo "shasum -a 256 "; elif hash sha256sum 2>/dev/null; then echo "sha256sum "; fi))
+endef
+
+# evaluation network (nnue)
+net:
+	$(call netvariables, EvalFileDefaultNameBig)
+	$(call fetch_network)
+	$(call netvariables, EvalFileDefaultNameSmall)
+	$(call fetch_network)
+
+format:
+	$(CLANG-FORMAT) -i $(SRCS) $(HEADERS) -style=file
+
+# default target
 default:
 	help
 
@@ -969,7 +1029,7 @@ config-sanity: net
 	@test "$(SUPPORTED_ARCH)" = "true"
 	@test "$(arch)" = "any" || test "$(arch)" = "x86_64" || test "$(arch)" = "i386" || \
 	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc" || test "$(arch)" = "e2k" || \
-	 test "$(arch)" = "armv7" || test "$(arch)" = "armv8" || test "$(arch)" = "arm64" || test "$(arch)" = "riscv64"
+	 test "$(arch)" = "armv7" || test "$(arch)" = "armv8" || test "$(arch)" = "arm64" || test "$(arch)" = "riscv64" || test "$(arch)" = "loongarch64"
 	@test "$(bits)" = "32" || test "$(bits)" = "64"
 	@test "$(prefetch)" = "yes" || test "$(prefetch)" = "no"
 	@test "$(popcnt)" = "yes" || test "$(popcnt)" = "no"

src/benchmark.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,18 +18,17 @@
 
 #include "benchmark.h"
 
+#include <cstdlib>
 #include <fstream>
 #include <iostream>
-#include <istream>
 #include <vector>
 
 #include "position.h"
 
-using namespace std;
-
 namespace {
 
-const vector<string> Defaults = {
+// clang-format off
+const std::vector<std::string> Defaults = {
   "setoption name UCI_Chess960 value false",
   "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1",
   "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq - 0 10",
@@ -92,86 +91,75 @@ const vector<string> Defaults = {
   "nqbnrkrb/pppppppp/8/8/8/8/PPPPPPPP/NQBNRKRB w KQkq - 0 1",
   "setoption name UCI_Chess960 value false"
 };
+// clang-format on
 
-} // namespace
+}  // namespace
 
 namespace Stockfish {
 
-/// setup_bench() builds a list of UCI commands to be run by bench. There
-/// are five parameters: TT size in MB, number of search threads that
-/// should be used, the limit value spent for each position, a file name
-/// where to look for positions in FEN format, the type of the limit:
-/// depth, perft, nodes and movetime (in millisecs), and evaluation type
-/// mixed (default), classical, NNUE.
-///
-/// bench -> search default positions up to depth 13
-/// bench 64 1 15 -> search default positions up to depth 15 (TT = 64MB)
-/// bench 64 4 5000 current movetime -> search current position with 4 threads for 5 sec
-/// bench 64 1 100000 default nodes -> search default positions for 100K nodes each
-/// bench 16 1 5 default perft -> run a perft 5 on default positions
+// Builds a list of UCI commands to be run by bench. There
+// are five parameters: TT size in MB, number of search threads that
+// should be used, the limit value spent for each position, a file name
+// where to look for positions in FEN format, and the type of the limit:
+// depth, perft, nodes and movetime (in milliseconds). Examples:
+//
+// bench                            : search default positions up to depth 13
+// bench 64 1 15                    : search default positions up to depth 15 (TT = 64MB)
+// bench 64 1 100000 default nodes  : search default positions for 100K nodes each
+// bench 64 4 5000 current movetime : search current position with 4 threads for 5 sec
+// bench 16 1 5 blah perft          : run a perft 5 on positions in file "blah"
+std::vector<std::string> setup_bench(const Position& current, std::istream& is) {
 
-vector<string> setup_bench(const Position& current, istream& is) {
+    std::vector<std::string> fens, list;
+    std::string              go, token;
 
-  vector<string> fens, list;
-  string go, token;
+    // Assign default values to missing arguments
+    std::string ttSize    = (is >> token) ? token : "16";
+    std::string threads   = (is >> token) ? token : "1";
+    std::string limit     = (is >> token) ? token : "13";
+    std::string fenFile   = (is >> token) ? token : "default";
+    std::string limitType = (is >> token) ? token : "depth";
 
-  // Assign default values to missing arguments
-  string ttSize    = (is >> token) ? token : "16";
-  string threads   = (is >> token) ? token : "1";
-  string limit     = (is >> token) ? token : "13";
-  string fenFile   = (is >> token) ? token : "default";
-  string limitType = (is >> token) ? token : "depth";
-  string evalType  = (is >> token) ? token : "mixed";
+    go = limitType == "eval" ? "eval" : "go " + limitType + " " + limit;
 
-  go = limitType == "eval" ? "eval" : "go " + limitType + " " + limit;
+    if (fenFile == "default")
+        fens = Defaults;
 
-  if (fenFile == "default")
-      fens = Defaults;
+    else if (fenFile == "current")
+        fens.push_back(current.fen());
 
-  else if (fenFile == "current")
-      fens.push_back(current.fen());
+    else
+    {
+        std::string   fen;
+        std::ifstream file(fenFile);
 
-  else
-  {
-      string fen;
-      ifstream file(fenFile);
+        if (!file.is_open())
+        {
+            std::cerr << "Unable to open file " << fenFile << std::endl;
+            exit(EXIT_FAILURE);
+        }
 
-      if (!file.is_open())
-      {
-          cerr << "Unable to open file " << fenFile << endl;
-          exit(EXIT_FAILURE);
-      }
+        while (getline(file, fen))
+            if (!fen.empty())
+                fens.push_back(fen);
 
-      while (getline(file, fen))
-          if (!fen.empty())
-              fens.push_back(fen);
+        file.close();
+    }
 
-      file.close();
-  }
+    list.emplace_back("setoption name Threads value " + threads);
+    list.emplace_back("setoption name Hash value " + ttSize);
+    list.emplace_back("ucinewgame");
 
-  list.emplace_back("setoption name Threads value " + threads);
-  list.emplace_back("setoption name Hash value " + ttSize);
-  list.emplace_back("ucinewgame");
+    for (const std::string& fen : fens)
+        if (fen.find("setoption") != std::string::npos)
+            list.emplace_back(fen);
+        else
+        {
+            list.emplace_back("position fen " + fen);
+            list.emplace_back(go);
+        }
 
-  size_t posCounter = 0;
-
-  for (const string& fen : fens)
-      if (fen.find("setoption") != string::npos)
-          list.emplace_back(fen);
-      else
-      {
-          if (evalType == "classical" || (evalType == "mixed" && posCounter % 2 == 0))
-              list.emplace_back("setoption name Use NNUE value false");
-          else if (evalType == "NNUE" || (evalType == "mixed" && posCounter % 2 != 0))
-              list.emplace_back("setoption name Use NNUE value true");
-          list.emplace_back("position fen " + fen);
-          list.emplace_back(go);
-          ++posCounter;
-      }
-
-  list.emplace_back("setoption name Use NNUE value true");
-
-  return list;
+    return list;
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/benchmark.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -29,6 +29,6 @@ class Position;
 
 std::vector<std::string> setup_bench(const Position&, std::istream&);
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#endif // #ifndef BENCHMARK_H_INCLUDED
+#endif  // #ifndef BENCHMARK_H_INCLUDED

src/bitbase.cpp

@@ -1,172 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <cassert>
-#include <vector>
-#include <bitset>
-
-#include "bitboard.h"
-#include "types.h"
-
-namespace Stockfish {
-
-namespace {
-
-  // There are 24 possible pawn squares: files A to D and ranks from 2 to 7.
-  // Positions with the pawn on files E to H will be mirrored before probing.
-  constexpr unsigned MAX_INDEX = 2*24*64*64; // stm * psq * wksq * bksq = 196608
-
-  std::bitset<MAX_INDEX> KPKBitbase;
-
-  // A KPK bitbase index is an integer in [0, IndexMax] range
-  //
-  // Information is mapped in a way that minimizes the number of iterations:
-  //
-  // bit  0- 5: white king square (from SQ_A1 to SQ_H8)
-  // bit  6-11: black king square (from SQ_A1 to SQ_H8)
-  // bit    12: side to move (WHITE or BLACK)
-  // bit 13-14: white pawn file (from FILE_A to FILE_D)
-  // bit 15-17: white pawn RANK_7 - rank (from RANK_7 - RANK_7 to RANK_7 - RANK_2)
-  unsigned index(Color stm, Square bksq, Square wksq, Square psq) {
-    return int(wksq) | (bksq << 6) | (stm << 12) | (file_of(psq) << 13) | ((RANK_7 - rank_of(psq)) << 15);
-  }
-
-  enum Result {
-    INVALID = 0,
-    UNKNOWN = 1,
-    DRAW    = 2,
-    WIN     = 4
-  };
-
-  Result& operator|=(Result& r, Result v) { return r = Result(r | v); }
-
-  struct KPKPosition {
-    KPKPosition() = default;
-    explicit KPKPosition(unsigned idx);
-    operator Result() const { return result; }
-    Result classify(const std::vector<KPKPosition>& db);
-
-    Color stm;
-    Square ksq[COLOR_NB], psq;
-    Result result;
-  };
-
-} // namespace
-
-bool Bitbases::probe(Square wksq, Square wpsq, Square bksq, Color stm) {
-
-  assert(file_of(wpsq) <= FILE_D);
-
-  return KPKBitbase[index(stm, bksq, wksq, wpsq)];
-}
-
-
-void Bitbases::init() {
-
-  std::vector<KPKPosition> db(MAX_INDEX);
-  unsigned idx, repeat = 1;
-
-  // Initialize db with known win / draw positions
-  for (idx = 0; idx < MAX_INDEX; ++idx)
-      db[idx] = KPKPosition(idx);
-
-  // Iterate through the positions until none of the unknown positions can be
-  // changed to either wins or draws (15 cycles needed).
-  while (repeat)
-      for (repeat = idx = 0; idx < MAX_INDEX; ++idx)
-          repeat |= (db[idx] == UNKNOWN && db[idx].classify(db) != UNKNOWN);
-
-  // Fill the bitbase with the decisive results
-  for (idx = 0; idx < MAX_INDEX; ++idx)
-      if (db[idx] == WIN)
-          KPKBitbase.set(idx);
-}
-
-namespace {
-
-  KPKPosition::KPKPosition(unsigned idx) {
-
-    ksq[WHITE] = Square((idx >>  0) & 0x3F);
-    ksq[BLACK] = Square((idx >>  6) & 0x3F);
-    stm        = Color ((idx >> 12) & 0x01);
-    psq        = make_square(File((idx >> 13) & 0x3), Rank(RANK_7 - ((idx >> 15) & 0x7)));
-
-    // Invalid if two pieces are on the same square or if a king can be captured
-    if (   distance(ksq[WHITE], ksq[BLACK]) <= 1
-        || ksq[WHITE] == psq
-        || ksq[BLACK] == psq
-        || (stm == WHITE && (pawn_attacks_bb(WHITE, psq) & ksq[BLACK])))
-        result = INVALID;
-
-    // Win if the pawn can be promoted without getting captured
-    else if (   stm == WHITE
-             && rank_of(psq) == RANK_7
-             && ksq[WHITE] != psq + NORTH
-             && (    distance(ksq[BLACK], psq + NORTH) > 1
-                 || (distance(ksq[WHITE], psq + NORTH) == 1)))
-        result = WIN;
-
-    // Draw if it is stalemate or the black king can capture the pawn
-    else if (   stm == BLACK
-             && (  !(attacks_bb<KING>(ksq[BLACK]) & ~(attacks_bb<KING>(ksq[WHITE]) | pawn_attacks_bb(WHITE, psq)))
-                 || (attacks_bb<KING>(ksq[BLACK]) & ~attacks_bb<KING>(ksq[WHITE]) & psq)))
-        result = DRAW;
-
-    // Position will be classified later
-    else
-        result = UNKNOWN;
-  }
-
-  Result KPKPosition::classify(const std::vector<KPKPosition>& db) {
-
-    // White to move: If one move leads to a position classified as WIN, the result
-    // of the current position is WIN. If all moves lead to positions classified
-    // as DRAW, the current position is classified as DRAW, otherwise the current
-    // position is classified as UNKNOWN.
-    //
-    // Black to move: If one move leads to a position classified as DRAW, the result
-    // of the current position is DRAW. If all moves lead to positions classified
-    // as WIN, the position is classified as WIN, otherwise the current position is
-    // classified as UNKNOWN.
-    const Result Good = (stm == WHITE ? WIN   : DRAW);
-    const Result Bad  = (stm == WHITE ? DRAW  : WIN);
-
-    Result r = INVALID;
-    Bitboard b = attacks_bb<KING>(ksq[stm]);
-
-    while (b)
-        r |= stm == WHITE ? db[index(BLACK, ksq[BLACK], pop_lsb(b), psq)]
-                          : db[index(WHITE, pop_lsb(b), ksq[WHITE], psq)];
-
-    if (stm == WHITE)
-    {
-        if (rank_of(psq) < RANK_7)      // Single push
-            r |= db[index(BLACK, ksq[BLACK], ksq[WHITE], psq + NORTH)];
-
-        if (   rank_of(psq) == RANK_2   // Double push
-            && psq + NORTH != ksq[WHITE]
-            && psq + NORTH != ksq[BLACK])
-            r |= db[index(BLACK, ksq[BLACK], ksq[WHITE], psq + NORTH + NORTH)];
-    }
-
-    return result = r & Good  ? Good  : r & UNKNOWN ? UNKNOWN : Bad;
-  }
-
-} // namespace
-
-} // namespace Stockfish

src/bitboard.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,12 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "bitboard.h"
+
 #include <algorithm>
 #include <bitset>
+#include <initializer_list>
 
-#include "bitboard.h"
 #include "misc.h"
 
 namespace Stockfish {
@@ -37,90 +39,86 @@ Magic BishopMagics[SQUARE_NB];
 
 namespace {
 
-  Bitboard RookTable[0x19000];  // To store rook attacks
-  Bitboard BishopTable[0x1480]; // To store bishop attacks
+Bitboard RookTable[0x19000];   // To store rook attacks
+Bitboard BishopTable[0x1480];  // To store bishop attacks
 
-  void init_magics(PieceType pt, Bitboard table[], Magic magics[]);
+void init_magics(PieceType pt, Bitboard table[], Magic magics[]);
 
-}
-
-/// safe_destination() returns the bitboard of target square for the given step
-/// from the given square. If the step is off the board, returns empty bitboard.
-
-inline Bitboard safe_destination(Square s, int step) {
+// Returns the bitboard of target square for the given step
+// from the given square. If the step is off the board, returns empty bitboard.
+Bitboard safe_destination(Square s, int step) {
     Square to = Square(s + step);
     return is_ok(to) && distance(s, to) <= 2 ? square_bb(to) : Bitboard(0);
 }
+}
 
-
-/// Bitboards::pretty() returns an ASCII representation of a bitboard suitable
-/// to be printed to standard output. Useful for debugging.
-
+// Returns an ASCII representation of a bitboard suitable
+// to be printed to standard output. Useful for debugging.
 std::string Bitboards::pretty(Bitboard b) {
 
-  std::string s = "+---+---+---+---+---+---+---+---+\n";
+    std::string s = "+---+---+---+---+---+---+---+---+\n";
 
-  for (Rank r = RANK_8; r >= RANK_1; --r)
-  {
-      for (File f = FILE_A; f <= FILE_H; ++f)
-          s += b & make_square(f, r) ? "| X " : "|   ";
+    for (Rank r = RANK_8; r >= RANK_1; --r)
+    {
+        for (File f = FILE_A; f <= FILE_H; ++f)
+            s += b & make_square(f, r) ? "| X " : "|   ";
 
-      s += "| " + std::to_string(1 + r) + "\n+---+---+---+---+---+---+---+---+\n";
-  }
-  s += "  a   b   c   d   e   f   g   h\n";
+        s += "| " + std::to_string(1 + r) + "\n+---+---+---+---+---+---+---+---+\n";
+    }
+    s += "  a   b   c   d   e   f   g   h\n";
 
-  return s;
+    return s;
 }
 
 
-/// Bitboards::init() initializes various bitboard tables. It is called at
-/// startup and relies on global objects to be already zero-initialized.
-
+// Initializes various bitboard tables. It is called at
+// startup and relies on global objects to be already zero-initialized.
 void Bitboards::init() {
 
-  for (unsigned i = 0; i < (1 << 16); ++i)
-      PopCnt16[i] = uint8_t(std::bitset<16>(i).count());
+    for (unsigned i = 0; i < (1 << 16); ++i)
+        PopCnt16[i] = uint8_t(std::bitset<16>(i).count());
 
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
-      for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
-          SquareDistance[s1][s2] = std::max(distance<File>(s1, s2), distance<Rank>(s1, s2));
+    for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
+        for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
+            SquareDistance[s1][s2] = std::max(distance<File>(s1, s2), distance<Rank>(s1, s2));
 
-  init_magics(ROOK, RookTable, RookMagics);
-  init_magics(BISHOP, BishopTable, BishopMagics);
+    init_magics(ROOK, RookTable, RookMagics);
+    init_magics(BISHOP, BishopTable, BishopMagics);
 
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
-  {
-      PawnAttacks[WHITE][s1] = pawn_attacks_bb<WHITE>(square_bb(s1));
-      PawnAttacks[BLACK][s1] = pawn_attacks_bb<BLACK>(square_bb(s1));
+    for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
+    {
+        PawnAttacks[WHITE][s1] = pawn_attacks_bb<WHITE>(square_bb(s1));
+        PawnAttacks[BLACK][s1] = pawn_attacks_bb<BLACK>(square_bb(s1));
 
-      for (int step : {-9, -8, -7, -1, 1, 7, 8, 9} )
-         PseudoAttacks[KING][s1] |= safe_destination(s1, step);
+        for (int step : {-9, -8, -7, -1, 1, 7, 8, 9})
+            PseudoAttacks[KING][s1] |= safe_destination(s1, step);
 
-      for (int step : {-17, -15, -10, -6, 6, 10, 15, 17} )
-         PseudoAttacks[KNIGHT][s1] |= safe_destination(s1, step);
+        for (int step : {-17, -15, -10, -6, 6, 10, 15, 17})
+            PseudoAttacks[KNIGHT][s1] |= safe_destination(s1, step);
 
-      PseudoAttacks[QUEEN][s1]  = PseudoAttacks[BISHOP][s1] = attacks_bb<BISHOP>(s1, 0);
-      PseudoAttacks[QUEEN][s1] |= PseudoAttacks[  ROOK][s1] = attacks_bb<  ROOK>(s1, 0);
+        PseudoAttacks[QUEEN][s1] = PseudoAttacks[BISHOP][s1] = attacks_bb<BISHOP>(s1, 0);
+        PseudoAttacks[QUEEN][s1] |= PseudoAttacks[ROOK][s1]  = attacks_bb<ROOK>(s1, 0);
 
-      for (PieceType pt : { BISHOP, ROOK })
-          for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
-          {
-              if (PseudoAttacks[pt][s1] & s2)
-              {
-                  LineBB[s1][s2]    = (attacks_bb(pt, s1, 0) & attacks_bb(pt, s2, 0)) | s1 | s2;
-                  BetweenBB[s1][s2] = (attacks_bb(pt, s1, square_bb(s2)) & attacks_bb(pt, s2, square_bb(s1)));
-              }
-              BetweenBB[s1][s2] |= s2;
-          }
-  }
+        for (PieceType pt : {BISHOP, ROOK})
+            for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
+            {
+                if (PseudoAttacks[pt][s1] & s2)
+                {
+                    LineBB[s1][s2] = (attacks_bb(pt, s1, 0) & attacks_bb(pt, s2, 0)) | s1 | s2;
+                    BetweenBB[s1][s2] =
+                      (attacks_bb(pt, s1, square_bb(s2)) & attacks_bb(pt, s2, square_bb(s1)));
+                }
+                BetweenBB[s1][s2] |= s2;
+            }
+    }
 }
 
 namespace {
 
-  Bitboard sliding_attack(PieceType pt, Square sq, Bitboard occupied) {
+Bitboard sliding_attack(PieceType pt, Square sq, Bitboard occupied) {
 
-    Bitboard attacks = 0;
-    Direction   RookDirections[4] = {NORTH, SOUTH, EAST, WEST};
+    Bitboard  attacks             = 0;
+    Direction RookDirections[4]   = {NORTH, SOUTH, EAST, WEST};
     Direction BishopDirections[4] = {NORTH_EAST, SOUTH_EAST, SOUTH_WEST, NORTH_WEST};
 
     for (Direction d : (pt == ROOK ? RookDirections : BishopDirections))
@@ -131,22 +129,21 @@ namespace {
     }
 
     return attacks;
-  }
+}
 
 
-  // init_magics() computes all rook and bishop attacks at startup. Magic
-  // bitboards are used to look up attacks of sliding pieces. As a reference see
-  // www.chessprogramming.org/Magic_Bitboards. In particular, here we use the so
-  // called "fancy" approach.
-
-  void init_magics(PieceType pt, Bitboard table[], Magic magics[]) {
+// Computes all rook and bishop attacks at startup. Magic
+// bitboards are used to look up attacks of sliding pieces. As a reference see
+// www.chessprogramming.org/Magic_Bitboards. In particular, here we use the so
+// called "fancy" approach.
+void init_magics(PieceType pt, Bitboard table[], Magic magics[]) {
 
     // Optimal PRNG seeds to pick the correct magics in the shortest time
-    int seeds[][RANK_NB] = { { 8977, 44560, 54343, 38998,  5731, 95205, 104912, 17020 },
-                             {  728, 10316, 55013, 32803, 12281, 15100,  16645,   255 } };
+    int seeds[][RANK_NB] = {{8977, 44560, 54343, 38998, 5731, 95205, 104912, 17020},
+                            {728, 10316, 55013, 32803, 12281, 15100, 16645, 255}};
 
     Bitboard occupancy[4096], reference[4096], edges, b;
-    int epoch[4096] = {}, cnt = 0, size = 0;
+    int      epoch[4096] = {}, cnt = 0, size = 0;
 
     for (Square s = SQ_A1; s <= SQ_H8; ++s)
     {
@@ -159,8 +156,8 @@ namespace {
         // the number of 1s of the mask. Hence we deduce the size of the shift to
         // apply to the 64 or 32 bits word to get the index.
         Magic& m = magics[s];
-        m.mask  = sliding_attack(pt, s, 0) & ~edges;
-        m.shift = (Is64Bit ? 64 : 32) - popcount(m.mask);
+        m.mask   = sliding_attack(pt, s, 0) & ~edges;
+        m.shift  = (Is64Bit ? 64 : 32) - popcount(m.mask);
 
         // Set the offset for the attacks table of the square. We have individual
         // table sizes for each square with "Fancy Magic Bitboards".
@@ -169,7 +166,8 @@ namespace {
         // Use Carry-Rippler trick to enumerate all subsets of masks[s] and
         // store the corresponding sliding attack bitboard in reference[].
         b = size = 0;
-        do {
+        do
+        {
             occupancy[size] = b;
             reference[size] = sliding_attack(pt, s, b);
 
@@ -187,9 +185,9 @@ namespace {
 
         // Find a magic for square 's' picking up an (almost) random number
         // until we find the one that passes the verification test.
-        for (int i = 0; i < size; )
+        for (int i = 0; i < size;)
         {
-            for (m.magic = 0; popcount((m.magic * m.mask) >> 56) < 6; )
+            for (m.magic = 0; popcount((m.magic * m.mask) >> 56) < 6;)
                 m.magic = rng.sparse_rand<Bitboard>();
 
             // A good magic must map every possible occupancy to an index that
@@ -204,7 +202,7 @@ namespace {
 
                 if (epoch[idx] < cnt)
                 {
-                    epoch[idx] = cnt;
+                    epoch[idx]     = cnt;
                     m.attacks[idx] = reference[i];
                 }
                 else if (m.attacks[idx] != reference[i])
@@ -212,7 +210,7 @@ namespace {
             }
         }
     }
-  }
+}
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/bitboard.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,28 +19,23 @@
 #ifndef BITBOARD_H_INCLUDED
 #define BITBOARD_H_INCLUDED
 
+#include <algorithm>
+#include <cassert>
+#include <cmath>
+#include <cstdint>
+#include <cstdlib>
 #include <string>
 
 #include "types.h"
 
 namespace Stockfish {
 
-namespace Bitbases {
-
-void init();
-bool probe(Square wksq, Square wpsq, Square bksq, Color us);
-
-} // namespace Stockfish::Bitbases
-
 namespace Bitboards {
 
-void init();
+void        init();
 std::string pretty(Bitboard b);
 
-} // namespace Stockfish::Bitboards
-
-constexpr Bitboard AllSquares = ~Bitboard(0);
-constexpr Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
+}  // namespace Stockfish::Bitboards
 
 constexpr Bitboard FileABB = 0x0101010101010101ULL;
 constexpr Bitboard FileBBB = FileABB << 1;
@@ -60,17 +55,6 @@ constexpr Bitboard Rank6BB = Rank1BB << (8 * 5);
 constexpr Bitboard Rank7BB = Rank1BB << (8 * 6);
 constexpr Bitboard Rank8BB = Rank1BB << (8 * 7);
 
-constexpr Bitboard QueenSide   = FileABB | FileBBB | FileCBB | FileDBB;
-constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
-constexpr Bitboard KingSide    = FileEBB | FileFBB | FileGBB | FileHBB;
-constexpr Bitboard Center      = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
-
-constexpr Bitboard KingFlank[FILE_NB] = {
-  QueenSide ^ FileDBB, QueenSide, QueenSide,
-  CenterFiles, CenterFiles,
-  KingSide, KingSide, KingSide ^ FileEBB
-};
-
 extern uint8_t PopCnt16[1 << 16];
 extern uint8_t SquareDistance[SQUARE_NB][SQUARE_NB];
 
@@ -80,371 +64,308 @@ extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 extern Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
 
 
-/// Magic holds all magic bitboards relevant data for a single square
+// Magic holds all magic bitboards relevant data for a single square
 struct Magic {
-  Bitboard  mask;
-  Bitboard  magic;
-  Bitboard* attacks;
-  unsigned  shift;
+    Bitboard  mask;
+    Bitboard  magic;
+    Bitboard* attacks;
+    unsigned  shift;
 
-  // Compute the attack's index using the 'magic bitboards' approach
-  unsigned index(Bitboard occupied) const {
+    // Compute the attack's index using the 'magic bitboards' approach
+    unsigned index(Bitboard occupied) const {
 
-    if (HasPext)
-        return unsigned(pext(occupied, mask));
+        if (HasPext)
+            return unsigned(pext(occupied, mask));
 
-    if (Is64Bit)
-        return unsigned(((occupied & mask) * magic) >> shift);
+        if (Is64Bit)
+            return unsigned(((occupied & mask) * magic) >> shift);
 
-    unsigned lo = unsigned(occupied) & unsigned(mask);
-    unsigned hi = unsigned(occupied >> 32) & unsigned(mask >> 32);
-    return (lo * unsigned(magic) ^ hi * unsigned(magic >> 32)) >> shift;
-  }
+        unsigned lo = unsigned(occupied) & unsigned(mask);
+        unsigned hi = unsigned(occupied >> 32) & unsigned(mask >> 32);
+        return (lo * unsigned(magic) ^ hi * unsigned(magic >> 32)) >> shift;
+    }
 };
 
 extern Magic RookMagics[SQUARE_NB];
 extern Magic BishopMagics[SQUARE_NB];
 
-inline Bitboard square_bb(Square s) {
-  assert(is_ok(s));
-  return (1ULL << s);
+constexpr Bitboard square_bb(Square s) {
+    assert(is_ok(s));
+    return (1ULL << s);
 }
 
 
-/// Overloads of bitwise operators between a Bitboard and a Square for testing
-/// whether a given bit is set in a bitboard, and for setting and clearing bits.
+// Overloads of bitwise operators between a Bitboard and a Square for testing
+// whether a given bit is set in a bitboard, and for setting and clearing bits.
 
-inline Bitboard  operator&( Bitboard  b, Square s) { return b &  square_bb(s); }
-inline Bitboard  operator|( Bitboard  b, Square s) { return b |  square_bb(s); }
-inline Bitboard  operator^( Bitboard  b, Square s) { return b ^  square_bb(s); }
+inline Bitboard  operator&(Bitboard b, Square s) { return b & square_bb(s); }
+inline Bitboard  operator|(Bitboard b, Square s) { return b | square_bb(s); }
+inline Bitboard  operator^(Bitboard b, Square s) { return b ^ square_bb(s); }
 inline Bitboard& operator|=(Bitboard& b, Square s) { return b |= square_bb(s); }
 inline Bitboard& operator^=(Bitboard& b, Square s) { return b ^= square_bb(s); }
 
-inline Bitboard  operator&(Square s, Bitboard b) { return b & s; }
-inline Bitboard  operator|(Square s, Bitboard b) { return b | s; }
-inline Bitboard  operator^(Square s, Bitboard b) { return b ^ s; }
+inline Bitboard operator&(Square s, Bitboard b) { return b & s; }
+inline Bitboard operator|(Square s, Bitboard b) { return b | s; }
+inline Bitboard operator^(Square s, Bitboard b) { return b ^ s; }
 
-inline Bitboard  operator|(Square s1, Square s2) { return square_bb(s1) | s2; }
+inline Bitboard operator|(Square s1, Square s2) { return square_bb(s1) | s2; }
 
-constexpr bool more_than_one(Bitboard b) {
-  return b & (b - 1);
-}
+constexpr bool more_than_one(Bitboard b) { return b & (b - 1); }
 
 
-constexpr bool opposite_colors(Square s1, Square s2) {
-  return (s1 + rank_of(s1) + s2 + rank_of(s2)) & 1;
-}
+// rank_bb() and file_bb() return a bitboard representing all the squares on
+// the given file or rank.
+
+constexpr Bitboard rank_bb(Rank r) { return Rank1BB << (8 * r); }
+
+constexpr Bitboard rank_bb(Square s) { return rank_bb(rank_of(s)); }
+
+constexpr Bitboard file_bb(File f) { return FileABB << f; }
+
+constexpr Bitboard file_bb(Square s) { return file_bb(file_of(s)); }
 
 
-/// rank_bb() and file_bb() return a bitboard representing all the squares on
-/// the given file or rank.
-
-constexpr Bitboard rank_bb(Rank r) {
-  return Rank1BB << (8 * r);
-}
-
-constexpr Bitboard rank_bb(Square s) {
-  return rank_bb(rank_of(s));
-}
-
-constexpr Bitboard file_bb(File f) {
-  return FileABB << f;
-}
-
-constexpr Bitboard file_bb(Square s) {
-  return file_bb(file_of(s));
-}
-
-
-/// shift() moves a bitboard one or two steps as specified by the direction D
-
+// Moves a bitboard one or two steps as specified by the direction D
 template<Direction D>
 constexpr Bitboard shift(Bitboard b) {
-  return  D == NORTH      ?  b             << 8 : D == SOUTH      ?  b             >> 8
-        : D == NORTH+NORTH?  b             <<16 : D == SOUTH+SOUTH?  b             >>16
-        : D == EAST       ? (b & ~FileHBB) << 1 : D == WEST       ? (b & ~FileABB) >> 1
-        : D == NORTH_EAST ? (b & ~FileHBB) << 9 : D == NORTH_WEST ? (b & ~FileABB) << 7
-        : D == SOUTH_EAST ? (b & ~FileHBB) >> 7 : D == SOUTH_WEST ? (b & ~FileABB) >> 9
-        : 0;
+    return D == NORTH         ? b << 8
+         : D == SOUTH         ? b >> 8
+         : D == NORTH + NORTH ? b << 16
+         : D == SOUTH + SOUTH ? b >> 16
+         : D == EAST          ? (b & ~FileHBB) << 1
+         : D == WEST          ? (b & ~FileABB) >> 1
+         : D == NORTH_EAST    ? (b & ~FileHBB) << 9
+         : D == NORTH_WEST    ? (b & ~FileABB) << 7
+         : D == SOUTH_EAST    ? (b & ~FileHBB) >> 7
+         : D == SOUTH_WEST    ? (b & ~FileABB) >> 9
+                              : 0;
 }
 
 
-/// pawn_attacks_bb() returns the squares attacked by pawns of the given color
-/// from the squares in the given bitboard.
-
+// Returns the squares attacked by pawns of the given color
+// from the squares in the given bitboard.
 template<Color C>
 constexpr Bitboard pawn_attacks_bb(Bitboard b) {
-  return C == WHITE ? shift<NORTH_WEST>(b) | shift<NORTH_EAST>(b)
-                    : shift<SOUTH_WEST>(b) | shift<SOUTH_EAST>(b);
+    return C == WHITE ? shift<NORTH_WEST>(b) | shift<NORTH_EAST>(b)
+                      : shift<SOUTH_WEST>(b) | shift<SOUTH_EAST>(b);
 }
 
 inline Bitboard pawn_attacks_bb(Color c, Square s) {
 
-  assert(is_ok(s));
-  return PawnAttacks[c][s];
+    assert(is_ok(s));
+    return PawnAttacks[c][s];
 }
 
-
-/// pawn_double_attacks_bb() returns the squares doubly attacked by pawns of the
-/// given color from the squares in the given bitboard.
-
-template<Color C>
-constexpr Bitboard pawn_double_attacks_bb(Bitboard b) {
-  return C == WHITE ? shift<NORTH_WEST>(b) & shift<NORTH_EAST>(b)
-                    : shift<SOUTH_WEST>(b) & shift<SOUTH_EAST>(b);
-}
-
-
-/// adjacent_files_bb() returns a bitboard representing all the squares on the
-/// adjacent files of a given square.
-
-constexpr Bitboard adjacent_files_bb(Square s) {
-  return shift<EAST>(file_bb(s)) | shift<WEST>(file_bb(s));
-}
-
-
-/// line_bb() returns a bitboard representing an entire line (from board edge
-/// to board edge) that intersects the two given squares. If the given squares
-/// are not on a same file/rank/diagonal, the function returns 0. For instance,
-/// line_bb(SQ_C4, SQ_F7) will return a bitboard with the A2-G8 diagonal.
-
+// Returns a bitboard representing an entire line (from board edge
+// to board edge) that intersects the two given squares. If the given squares
+// are not on a same file/rank/diagonal, the function returns 0. For instance,
+// line_bb(SQ_C4, SQ_F7) will return a bitboard with the A2-G8 diagonal.
 inline Bitboard line_bb(Square s1, Square s2) {
 
-  assert(is_ok(s1) && is_ok(s2));
-
-  return LineBB[s1][s2];
+    assert(is_ok(s1) && is_ok(s2));
+    return LineBB[s1][s2];
 }
 
 
-/// between_bb(s1, s2) returns a bitboard representing the squares in the semi-open
-/// segment between the squares s1 and s2 (excluding s1 but including s2). If the
-/// given squares are not on a same file/rank/diagonal, it returns s2. For instance,
-/// between_bb(SQ_C4, SQ_F7) will return a bitboard with squares D5, E6 and F7, but
-/// between_bb(SQ_E6, SQ_F8) will return a bitboard with the square F8. This trick
-/// allows to generate non-king evasion moves faster: the defending piece must either
-/// interpose itself to cover the check or capture the checking piece.
-
+// Returns a bitboard representing the squares in the semi-open
+// segment between the squares s1 and s2 (excluding s1 but including s2). If the
+// given squares are not on a same file/rank/diagonal, it returns s2. For instance,
+// between_bb(SQ_C4, SQ_F7) will return a bitboard with squares D5, E6 and F7, but
+// between_bb(SQ_E6, SQ_F8) will return a bitboard with the square F8. This trick
+// allows to generate non-king evasion moves faster: the defending piece must either
+// interpose itself to cover the check or capture the checking piece.
 inline Bitboard between_bb(Square s1, Square s2) {
 
-  assert(is_ok(s1) && is_ok(s2));
-
-  return BetweenBB[s1][s2];
+    assert(is_ok(s1) && is_ok(s2));
+    return BetweenBB[s1][s2];
 }
 
+// Returns true if the squares s1, s2 and s3 are aligned either on a
+// straight or on a diagonal line.
+inline bool aligned(Square s1, Square s2, Square s3) { return line_bb(s1, s2) & s3; }
 
-/// forward_ranks_bb() returns a bitboard representing the squares on the ranks in
-/// front of the given one, from the point of view of the given color. For instance,
-/// forward_ranks_bb(BLACK, SQ_D3) will return the 16 squares on ranks 1 and 2.
 
-constexpr Bitboard forward_ranks_bb(Color c, Square s) {
-  return c == WHITE ? ~Rank1BB << 8 * relative_rank(WHITE, s)
-                    : ~Rank8BB >> 8 * relative_rank(BLACK, s);
+// distance() functions return the distance between x and y, defined as the
+// number of steps for a king in x to reach y.
+
+template<typename T1 = Square>
+inline int distance(Square x, Square y);
+
+template<>
+inline int distance<File>(Square x, Square y) {
+    return std::abs(file_of(x) - file_of(y));
 }
 
-
-/// forward_file_bb() returns a bitboard representing all the squares along the
-/// line in front of the given one, from the point of view of the given color.
-
-constexpr Bitboard forward_file_bb(Color c, Square s) {
-  return forward_ranks_bb(c, s) & file_bb(s);
+template<>
+inline int distance<Rank>(Square x, Square y) {
+    return std::abs(rank_of(x) - rank_of(y));
 }
 
-
-/// pawn_attack_span() returns a bitboard representing all the squares that can
-/// be attacked by a pawn of the given color when it moves along its file, starting
-/// from the given square.
-
-constexpr Bitboard pawn_attack_span(Color c, Square s) {
-  return forward_ranks_bb(c, s) & adjacent_files_bb(s);
+template<>
+inline int distance<Square>(Square x, Square y) {
+    return SquareDistance[x][y];
 }
 
-
-/// passed_pawn_span() returns a bitboard which can be used to test if a pawn of
-/// the given color and on the given square is a passed pawn.
-
-constexpr Bitboard passed_pawn_span(Color c, Square s) {
-  return pawn_attack_span(c, s) | forward_file_bb(c, s);
-}
-
-
-/// aligned() returns true if the squares s1, s2 and s3 are aligned either on a
-/// straight or on a diagonal line.
-
-inline bool aligned(Square s1, Square s2, Square s3) {
-  return line_bb(s1, s2) & s3;
-}
-
-
-/// distance() functions return the distance between x and y, defined as the
-/// number of steps for a king in x to reach y.
-
-template<typename T1 = Square> inline int distance(Square x, Square y);
-template<> inline int distance<File>(Square x, Square y) { return std::abs(file_of(x) - file_of(y)); }
-template<> inline int distance<Rank>(Square x, Square y) { return std::abs(rank_of(x) - rank_of(y)); }
-template<> inline int distance<Square>(Square x, Square y) { return SquareDistance[x][y]; }
-
 inline int edge_distance(File f) { return std::min(f, File(FILE_H - f)); }
-inline int edge_distance(Rank r) { return std::min(r, Rank(RANK_8 - r)); }
-
-
-/// attacks_bb(Square) returns the pseudo attacks of the give piece type
-/// assuming an empty board.
 
+// Returns the pseudo attacks of the given piece type
+// assuming an empty board.
 template<PieceType Pt>
 inline Bitboard attacks_bb(Square s) {
 
-  assert((Pt != PAWN) && (is_ok(s)));
-
-  return PseudoAttacks[Pt][s];
+    assert((Pt != PAWN) && (is_ok(s)));
+    return PseudoAttacks[Pt][s];
 }
 
 
-/// attacks_bb(Square, Bitboard) returns the attacks by the given piece
-/// assuming the board is occupied according to the passed Bitboard.
-/// Sliding piece attacks do not continue passed an occupied square.
-
+// Returns the attacks by the given piece
+// assuming the board is occupied according to the passed Bitboard.
+// Sliding piece attacks do not continue passed an occupied square.
 template<PieceType Pt>
 inline Bitboard attacks_bb(Square s, Bitboard occupied) {
 
-  assert((Pt != PAWN) && (is_ok(s)));
+    assert((Pt != PAWN) && (is_ok(s)));
 
-  switch (Pt)
-  {
-  case BISHOP: return BishopMagics[s].attacks[BishopMagics[s].index(occupied)];
-  case ROOK  : return   RookMagics[s].attacks[  RookMagics[s].index(occupied)];
-  case QUEEN : return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
-  default    : return PseudoAttacks[Pt][s];
-  }
+    switch (Pt)
+    {
+    case BISHOP :
+        return BishopMagics[s].attacks[BishopMagics[s].index(occupied)];
+    case ROOK :
+        return RookMagics[s].attacks[RookMagics[s].index(occupied)];
+    case QUEEN :
+        return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
+    default :
+        return PseudoAttacks[Pt][s];
+    }
 }
 
+// Returns the attacks by the given piece
+// assuming the board is occupied according to the passed Bitboard.
+// Sliding piece attacks do not continue passed an occupied square.
 inline Bitboard attacks_bb(PieceType pt, Square s, Bitboard occupied) {
 
-  assert((pt != PAWN) && (is_ok(s)));
+    assert((pt != PAWN) && (is_ok(s)));
 
-  switch (pt)
-  {
-  case BISHOP: return attacks_bb<BISHOP>(s, occupied);
-  case ROOK  : return attacks_bb<  ROOK>(s, occupied);
-  case QUEEN : return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
-  default    : return PseudoAttacks[pt][s];
-  }
+    switch (pt)
+    {
+    case BISHOP :
+        return attacks_bb<BISHOP>(s, occupied);
+    case ROOK :
+        return attacks_bb<ROOK>(s, occupied);
+    case QUEEN :
+        return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
+    default :
+        return PseudoAttacks[pt][s];
+    }
 }
 
 
-/// popcount() counts the number of non-zero bits in a bitboard
-
+// Counts the number of non-zero bits in a bitboard.
 inline int popcount(Bitboard b) {
 
 #ifndef USE_POPCNT
 
-  union { Bitboard bb; uint16_t u[4]; } v = { b };
-  return PopCnt16[v.u[0]] + PopCnt16[v.u[1]] + PopCnt16[v.u[2]] + PopCnt16[v.u[3]];
+    union {
+        Bitboard bb;
+        uint16_t u[4];
+    } v = {b};
+    return PopCnt16[v.u[0]] + PopCnt16[v.u[1]] + PopCnt16[v.u[2]] + PopCnt16[v.u[3]];
 
-#elif defined(_MSC_VER) || defined(__INTEL_COMPILER)
+#elif defined(_MSC_VER)
 
-  return (int)_mm_popcnt_u64(b);
+    return int(_mm_popcnt_u64(b));
 
-#else // Assumed gcc or compatible compiler
+#else  // Assumed gcc or compatible compiler
 
-  return __builtin_popcountll(b);
+    return __builtin_popcountll(b);
 
 #endif
 }
 
-
-/// lsb() and msb() return the least/most significant bit in a non-zero bitboard
-
-#if defined(__GNUC__)  // GCC, Clang, ICC
-
+// Returns the least significant bit in a non-zero bitboard.
 inline Square lsb(Bitboard b) {
-  assert(b);
-  return Square(__builtin_ctzll(b));
-}
+    assert(b);
 
-inline Square msb(Bitboard b) {
-  assert(b);
-  return Square(63 ^ __builtin_clzll(b));
-}
+#if defined(__GNUC__)  // GCC, Clang, ICX
 
-#elif defined(_MSC_VER)  // MSVC
+    return Square(__builtin_ctzll(b));
 
-#ifdef _WIN64  // MSVC, WIN64
+#elif defined(_MSC_VER)
+    #ifdef _WIN64  // MSVC, WIN64
 
-inline Square lsb(Bitboard b) {
-  assert(b);
-  unsigned long idx;
-  _BitScanForward64(&idx, b);
-  return (Square) idx;
-}
+    unsigned long idx;
+    _BitScanForward64(&idx, b);
+    return Square(idx);
 
-inline Square msb(Bitboard b) {
-  assert(b);
-  unsigned long idx;
-  _BitScanReverse64(&idx, b);
-  return (Square) idx;
-}
-
-#else  // MSVC, WIN32
-
-inline Square lsb(Bitboard b) {
-  assert(b);
-  unsigned long idx;
-
-  if (b & 0xffffffff) {
-      _BitScanForward(&idx, int32_t(b));
-      return Square(idx);
-  } else {
-      _BitScanForward(&idx, int32_t(b >> 32));
-      return Square(idx + 32);
-  }
-}
-
-inline Square msb(Bitboard b) {
-  assert(b);
-  unsigned long idx;
-
-  if (b >> 32) {
-      _BitScanReverse(&idx, int32_t(b >> 32));
-      return Square(idx + 32);
-  } else {
-      _BitScanReverse(&idx, int32_t(b));
-      return Square(idx);
-  }
-}
-
-#endif
+    #else  // MSVC, WIN32
+    unsigned long idx;
 
+    if (b & 0xffffffff)
+    {
+        _BitScanForward(&idx, int32_t(b));
+        return Square(idx);
+    }
+    else
+    {
+        _BitScanForward(&idx, int32_t(b >> 32));
+        return Square(idx + 32);
+    }
+    #endif
 #else  // Compiler is neither GCC nor MSVC compatible
-
-#error "Compiler not supported."
-
+    #error "Compiler not supported."
 #endif
+}
 
-/// least_significant_square_bb() returns the bitboard of the least significant
-/// square of a non-zero bitboard. It is equivalent to square_bb(lsb(bb)).
+// Returns the most significant bit in a non-zero bitboard.
+inline Square msb(Bitboard b) {
+    assert(b);
 
+#if defined(__GNUC__)  // GCC, Clang, ICX
+
+    return Square(63 ^ __builtin_clzll(b));
+
+#elif defined(_MSC_VER)
+    #ifdef _WIN64  // MSVC, WIN64
+
+    unsigned long idx;
+    _BitScanReverse64(&idx, b);
+    return Square(idx);
+
+    #else  // MSVC, WIN32
+
+    unsigned long idx;
+
+    if (b >> 32)
+    {
+        _BitScanReverse(&idx, int32_t(b >> 32));
+        return Square(idx + 32);
+    }
+    else
+    {
+        _BitScanReverse(&idx, int32_t(b));
+        return Square(idx);
+    }
+    #endif
+#else  // Compiler is neither GCC nor MSVC compatible
+    #error "Compiler not supported."
+#endif
+}
+
+// Returns the bitboard of the least significant
+// square of a non-zero bitboard. It is equivalent to square_bb(lsb(bb)).
 inline Bitboard least_significant_square_bb(Bitboard b) {
-  assert(b);
-  return b & -b;
+    assert(b);
+    return b & -b;
 }
 
-/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard
-
+// Finds and clears the least significant bit in a non-zero bitboard.
 inline Square pop_lsb(Bitboard& b) {
-  assert(b);
-  const Square s = lsb(b);
-  b &= b - 1;
-  return s;
+    assert(b);
+    const Square s = lsb(b);
+    b &= b - 1;
+    return s;
 }
 
+}  // namespace Stockfish
 
-/// frontmost_sq() returns the most advanced square for the given color,
-/// requires a non-zero bitboard.
-inline Square frontmost_sq(Color c, Bitboard b) {
-  assert(b);
-  return c == WHITE ? msb(b) : lsb(b);
-}
-
-} // namespace Stockfish
-
-#endif // #ifndef BITBOARD_H_INCLUDED
+#endif  // #ifndef BITBOARD_H_INCLUDED

src/endgame.cpp

@@ -1,747 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <cassert>
-
-#include "bitboard.h"
-#include "endgame.h"
-#include "movegen.h"
-
-namespace Stockfish {
-
-namespace {
-
-  // Used to drive the king towards the edge of the board
-  // in KX vs K and KQ vs KR endgames.
-  // Values range from 27 (center squares) to 90 (in the corners)
-  inline int push_to_edge(Square s) {
-      int rd = edge_distance(rank_of(s)), fd = edge_distance(file_of(s));
-      return 90 - (7 * fd * fd / 2 + 7 * rd * rd / 2);
-  }
-
-  // Used to drive the king towards A1H8 corners in KBN vs K endgames.
-  // Values range from 0 on A8H1 diagonal to 7 in A1H8 corners
-  inline int push_to_corner(Square s) {
-      return abs(7 - rank_of(s) - file_of(s));
-  }
-
-  // Drive a piece close to or away from another piece
-  inline int push_close(Square s1, Square s2) { return 140 - 20 * distance(s1, s2); }
-  inline int push_away(Square s1, Square s2) { return 120 - push_close(s1, s2); }
-
-#ifndef NDEBUG
-  bool verify_material(const Position& pos, Color c, Value npm, int pawnsCnt) {
-    return pos.non_pawn_material(c) == npm && pos.count<PAWN>(c) == pawnsCnt;
-  }
-#endif
-
-  // Map the square as if strongSide is white and strongSide's only pawn
-  // is on the left half of the board.
-  Square normalize(const Position& pos, Color strongSide, Square sq) {
-
-    assert(pos.count<PAWN>(strongSide) == 1);
-
-    if (file_of(pos.square<PAWN>(strongSide)) >= FILE_E)
-        sq = flip_file(sq);
-
-    return strongSide == WHITE ? sq : flip_rank(sq);
-  }
-
-} // namespace
-
-
-namespace Endgames {
-
-  std::pair<Map<Value>, Map<ScaleFactor>> maps;
-
-  void init() {
-
-    add<KPK>("KPK");
-    add<KNNK>("KNNK");
-    add<KBNK>("KBNK");
-    add<KRKP>("KRKP");
-    add<KRKB>("KRKB");
-    add<KRKN>("KRKN");
-    add<KQKP>("KQKP");
-    add<KQKR>("KQKR");
-    add<KNNKP>("KNNKP");
-
-    add<KRPKR>("KRPKR");
-    add<KRPKB>("KRPKB");
-    add<KBPKB>("KBPKB");
-    add<KBPKN>("KBPKN");
-    add<KBPPKB>("KBPPKB");
-    add<KRPPKRP>("KRPPKRP");
-  }
-}
-
-
-/// Mate with KX vs K. This function is used to evaluate positions with
-/// king and plenty of material vs a lone king. It simply gives the
-/// attacking side a bonus for driving the defending king towards the edge
-/// of the board, and for keeping the distance between the two kings small.
-template<>
-Value Endgame<KXK>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
-  assert(!pos.checkers()); // Eval is never called when in check
-
-  // Stalemate detection with lone king
-  if (pos.side_to_move() == weakSide && !MoveList<LEGAL>(pos).size())
-      return VALUE_DRAW;
-
-  Square strongKing = pos.square<KING>(strongSide);
-  Square weakKing   = pos.square<KING>(weakSide);
-
-  Value result =  pos.non_pawn_material(strongSide)
-                + pos.count<PAWN>(strongSide) * PawnValueEg
-                + push_to_edge(weakKing)
-                + push_close(strongKing, weakKing);
-
-  if (   pos.count<QUEEN>(strongSide)
-      || pos.count<ROOK>(strongSide)
-      ||(pos.count<BISHOP>(strongSide) && pos.count<KNIGHT>(strongSide))
-      || (   (pos.pieces(strongSide, BISHOP) & ~DarkSquares)
-          && (pos.pieces(strongSide, BISHOP) &  DarkSquares)))
-      result = std::min(result + VALUE_KNOWN_WIN, VALUE_TB_WIN_IN_MAX_PLY - 1);
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// Mate with KBN vs K. This is similar to KX vs K, but we have to drive the
-/// defending king towards a corner square that our bishop attacks.
-template<>
-Value Endgame<KBNK>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, KnightValueMg + BishopValueMg, 0));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
-
-  Square strongKing   = pos.square<KING>(strongSide);
-  Square strongBishop = pos.square<BISHOP>(strongSide);
-  Square weakKing     = pos.square<KING>(weakSide);
-
-  // If our bishop does not attack A1/H8, we flip the enemy king square
-  // to drive to opposite corners (A8/H1).
-
-  Value result =  (VALUE_KNOWN_WIN + 3520)
-                + push_close(strongKing, weakKing)
-                + 420 * push_to_corner(opposite_colors(strongBishop, SQ_A1) ? flip_file(weakKing) : weakKing);
-
-  assert(abs(result) < VALUE_TB_WIN_IN_MAX_PLY);
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KP vs K. This endgame is evaluated with the help of a bitbase
-template<>
-Value Endgame<KPK>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, VALUE_ZERO, 1));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
-
-  // Assume strongSide is white and the pawn is on files A-D
-  Square strongKing = normalize(pos, strongSide, pos.square<KING>(strongSide));
-  Square strongPawn = normalize(pos, strongSide, pos.square<PAWN>(strongSide));
-  Square weakKing   = normalize(pos, strongSide, pos.square<KING>(weakSide));
-
-  Color us = strongSide == pos.side_to_move() ? WHITE : BLACK;
-
-  if (!Bitbases::probe(strongKing, strongPawn, weakKing, us))
-      return VALUE_DRAW;
-
-  Value result = VALUE_KNOWN_WIN + PawnValueEg + Value(rank_of(strongPawn));
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KR vs KP. This is a somewhat tricky endgame to evaluate precisely without
-/// a bitbase. The function below returns drawish scores when the pawn is
-/// far advanced with support of the king, while the attacking king is far
-/// away.
-template<>
-Value Endgame<KRKP>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 0));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 1));
-
-  Square strongKing = pos.square<KING>(strongSide);
-  Square weakKing   = pos.square<KING>(weakSide);
-  Square strongRook = pos.square<ROOK>(strongSide);
-  Square weakPawn   = pos.square<PAWN>(weakSide);
-  Square queeningSquare = make_square(file_of(weakPawn), relative_rank(weakSide, RANK_8));
-  Value result;
-
-  // If the stronger side's king is in front of the pawn, it's a win
-  if (forward_file_bb(strongSide, strongKing) & weakPawn)
-      result = RookValueEg - distance(strongKing, weakPawn);
-
-  // If the weaker side's king is too far from the pawn and the rook,
-  // it's a win.
-  else if (   distance(weakKing, weakPawn) >= 3 + (pos.side_to_move() == weakSide)
-           && distance(weakKing, strongRook) >= 3)
-      result = RookValueEg - distance(strongKing, weakPawn);
-
-  // If the pawn is far advanced and supported by the defending king,
-  // the position is drawish
-  else if (   relative_rank(strongSide, weakKing) <= RANK_3
-           && distance(weakKing, weakPawn) == 1
-           && relative_rank(strongSide, strongKing) >= RANK_4
-           && distance(strongKing, weakPawn) > 2 + (pos.side_to_move() == strongSide))
-      result = Value(80) - 8 * distance(strongKing, weakPawn);
-
-  else
-      result =  Value(200) - 8 * (  distance(strongKing, weakPawn + pawn_push(weakSide))
-                                  - distance(weakKing, weakPawn + pawn_push(weakSide))
-                                  - distance(weakPawn, queeningSquare));
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KR vs KB. This is very simple, and always returns drawish scores. The
-/// score is slightly bigger when the defending king is close to the edge.
-template<>
-Value Endgame<KRKB>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 0));
-  assert(verify_material(pos, weakSide, BishopValueMg, 0));
-
-  Value result = Value(push_to_edge(pos.square<KING>(weakSide)));
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KR vs KN. The attacking side has slightly better winning chances than
-/// in KR vs KB, particularly if the king and the knight are far apart.
-template<>
-Value Endgame<KRKN>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 0));
-  assert(verify_material(pos, weakSide, KnightValueMg, 0));
-
-  Square weakKing   = pos.square<KING>(weakSide);
-  Square weakKnight = pos.square<KNIGHT>(weakSide);
-  Value result = Value(push_to_edge(weakKing) + push_away(weakKing, weakKnight));
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KQ vs KP. In general, this is a win for the stronger side, but there are a
-/// few important exceptions. A pawn on 7th rank and on the A,C,F or H files
-/// with a king positioned next to it can be a draw, so in that case, we only
-/// use the distance between the kings.
-template<>
-Value Endgame<KQKP>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, QueenValueMg, 0));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 1));
-
-  Square strongKing = pos.square<KING>(strongSide);
-  Square weakKing   = pos.square<KING>(weakSide);
-  Square weakPawn   = pos.square<PAWN>(weakSide);
-
-  Value result = Value(push_close(strongKing, weakKing));
-
-  if (   relative_rank(weakSide, weakPawn) != RANK_7
-      || distance(weakKing, weakPawn) != 1
-      || ((FileBBB | FileDBB | FileEBB | FileGBB) & weakPawn))
-      result += QueenValueEg - PawnValueEg;
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KQ vs KR. This is almost identical to KX vs K: we give the attacking
-/// king a bonus for having the kings close together, and for forcing the
-/// defending king towards the edge. If we also take care to avoid null move for
-/// the defending side in the search, this is usually sufficient to win KQ vs KR.
-template<>
-Value Endgame<KQKR>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, QueenValueMg, 0));
-  assert(verify_material(pos, weakSide, RookValueMg, 0));
-
-  Square strongKing = pos.square<KING>(strongSide);
-  Square weakKing   = pos.square<KING>(weakSide);
-
-  Value result =  QueenValueEg
-                - RookValueEg
-                + push_to_edge(weakKing)
-                + push_close(strongKing, weakKing);
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// KNN vs KP. Very drawish, but there are some mate opportunities if we can
-/// press the weakSide King to a corner before the pawn advances too much.
-template<>
-Value Endgame<KNNKP>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, 2 * KnightValueMg, 0));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 1));
-
-  Square weakKing = pos.square<KING>(weakSide);
-  Square weakPawn = pos.square<PAWN>(weakSide);
-
-  Value result =      PawnValueEg
-               +  2 * push_to_edge(weakKing)
-               - 10 * relative_rank(weakSide, weakPawn);
-
-  return strongSide == pos.side_to_move() ? result : -result;
-}
-
-
-/// Some cases of trivial draws
-template<> Value Endgame<KNNK>::operator()(const Position&) const { return VALUE_DRAW; }
-
-
-/// KB and one or more pawns vs K. It checks for draws with rook pawns and
-/// a bishop of the wrong color. If such a draw is detected, SCALE_FACTOR_DRAW
-/// is returned. If not, the return value is SCALE_FACTOR_NONE, i.e. no scaling
-/// will be used.
-template<>
-ScaleFactor Endgame<KBPsK>::operator()(const Position& pos) const {
-
-  assert(pos.non_pawn_material(strongSide) == BishopValueMg);
-  assert(pos.count<PAWN>(strongSide) >= 1);
-
-  // No assertions about the material of weakSide, because we want draws to
-  // be detected even when the weaker side has some pawns.
-
-  Bitboard strongPawns = pos.pieces(strongSide, PAWN);
-  Bitboard allPawns = pos.pieces(PAWN);
-
-  Square strongBishop = pos.square<BISHOP>(strongSide);
-  Square weakKing = pos.square<KING>(weakSide);
-  Square strongKing = pos.square<KING>(strongSide);
-
-  // All strongSide pawns are on a single rook file?
-  if (!(strongPawns & ~FileABB) || !(strongPawns & ~FileHBB))
-  {
-      Square queeningSquare = relative_square(strongSide, make_square(file_of(lsb(strongPawns)), RANK_8));
-
-      if (   opposite_colors(queeningSquare, strongBishop)
-          && distance(queeningSquare, weakKing) <= 1)
-          return SCALE_FACTOR_DRAW;
-  }
-
-  // If all the pawns are on the same B or G file, then it's potentially a draw
-  if ((!(allPawns & ~FileBBB) || !(allPawns & ~FileGBB))
-      && pos.non_pawn_material(weakSide) == 0
-      && pos.count<PAWN>(weakSide) >= 1)
-  {
-      // Get the least advanced weakSide pawn
-      Square weakPawn = frontmost_sq(strongSide, pos.pieces(weakSide, PAWN));
-
-      // There's potential for a draw if our pawn is blocked on the 7th rank,
-      // the bishop cannot attack it or they only have one pawn left.
-      if (   relative_rank(strongSide, weakPawn) == RANK_7
-          && (strongPawns & (weakPawn + pawn_push(weakSide)))
-          && (opposite_colors(strongBishop, weakPawn) || !more_than_one(strongPawns)))
-      {
-          int strongKingDist = distance(weakPawn, strongKing);
-          int weakKingDist = distance(weakPawn, weakKing);
-
-          // It's a draw if the weak king is on its back two ranks, within 2
-          // squares of the blocking pawn and the strong king is not
-          // closer. (I think this rule only fails in practically
-          // unreachable positions such as 5k1K/6p1/6P1/8/8/3B4/8/8 w
-          // and positions where qsearch will immediately correct the
-          // problem such as 8/4k1p1/6P1/1K6/3B4/8/8/8 w).
-          if (   relative_rank(strongSide, weakKing) >= RANK_7
-              && weakKingDist <= 2
-              && weakKingDist <= strongKingDist)
-              return SCALE_FACTOR_DRAW;
-      }
-  }
-
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// KQ vs KR and one or more pawns. It tests for fortress draws with a rook on
-/// the third rank defended by a pawn.
-template<>
-ScaleFactor Endgame<KQKRPs>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, QueenValueMg, 0));
-  assert(pos.count<ROOK>(weakSide) == 1);
-  assert(pos.count<PAWN>(weakSide) >= 1);
-
-  Square strongKing = pos.square<KING>(strongSide);
-  Square weakKing   = pos.square<KING>(weakSide);
-  Square weakRook   = pos.square<ROOK>(weakSide);
-
-  if (    relative_rank(weakSide,   weakKing) <= RANK_2
-      &&  relative_rank(weakSide, strongKing) >= RANK_4
-      &&  relative_rank(weakSide,   weakRook) == RANK_3
-      && (  pos.pieces(weakSide, PAWN)
-          & attacks_bb<KING>(weakKing)
-          & pawn_attacks_bb(strongSide, weakRook)))
-          return SCALE_FACTOR_DRAW;
-
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// KRP vs KR. This function knows a handful of the most important classes of
-/// drawn positions, but is far from perfect. It would probably be a good idea
-/// to add more knowledge in the future.
-///
-/// It would also be nice to rewrite the actual code for this function,
-/// which is mostly copied from Glaurung 1.x, and isn't very pretty.
-template<>
-ScaleFactor Endgame<KRPKR>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 1));
-  assert(verify_material(pos, weakSide,   RookValueMg, 0));
-
-  // Assume strongSide is white and the pawn is on files A-D
-  Square strongKing = normalize(pos, strongSide, pos.square<KING>(strongSide));
-  Square strongRook = normalize(pos, strongSide, pos.square<ROOK>(strongSide));
-  Square strongPawn = normalize(pos, strongSide, pos.square<PAWN>(strongSide));
-  Square weakKing = normalize(pos, strongSide, pos.square<KING>(weakSide));
-  Square weakRook = normalize(pos, strongSide, pos.square<ROOK>(weakSide));
-
-  File pawnFile = file_of(strongPawn);
-  Rank pawnRank = rank_of(strongPawn);
-  Square queeningSquare = make_square(pawnFile, RANK_8);
-  int tempo = (pos.side_to_move() == strongSide);
-
-  // If the pawn is not too far advanced and the defending king defends the
-  // queening square, use the third-rank defence.
-  if (   pawnRank <= RANK_5
-      && distance(weakKing, queeningSquare) <= 1
-      && strongKing <= SQ_H5
-      && (rank_of(weakRook) == RANK_6 || (pawnRank <= RANK_3 && rank_of(strongRook) != RANK_6)))
-      return SCALE_FACTOR_DRAW;
-
-  // The defending side saves a draw by checking from behind in case the pawn
-  // has advanced to the 6th rank with the king behind.
-  if (   pawnRank == RANK_6
-      && distance(weakKing, queeningSquare) <= 1
-      && rank_of(strongKing) + tempo <= RANK_6
-      && (rank_of(weakRook) == RANK_1 || (!tempo && distance<File>(weakRook, strongPawn) >= 3)))
-      return SCALE_FACTOR_DRAW;
-
-  if (   pawnRank >= RANK_6
-      && weakKing == queeningSquare
-      && rank_of(weakRook) == RANK_1
-      && (!tempo || distance(strongKing, strongPawn) >= 2))
-      return SCALE_FACTOR_DRAW;
-
-  // White pawn on a7 and rook on a8 is a draw if black's king is on g7 or h7
-  // and the black rook is behind the pawn.
-  if (   strongPawn == SQ_A7
-      && strongRook == SQ_A8
-      && (weakKing == SQ_H7 || weakKing == SQ_G7)
-      && file_of(weakRook) == FILE_A
-      && (rank_of(weakRook) <= RANK_3 || file_of(strongKing) >= FILE_D || rank_of(strongKing) <= RANK_5))
-      return SCALE_FACTOR_DRAW;
-
-  // If the defending king blocks the pawn and the attacking king is too far
-  // away, it's a draw.
-  if (   pawnRank <= RANK_5
-      && weakKing == strongPawn + NORTH
-      && distance(strongKing, strongPawn) - tempo >= 2
-      && distance(strongKing, weakRook) - tempo >= 2)
-      return SCALE_FACTOR_DRAW;
-
-  // Pawn on the 7th rank supported by the rook from behind usually wins if the
-  // attacking king is closer to the queening square than the defending king,
-  // and the defending king cannot gain tempi by threatening the attacking rook.
-  if (   pawnRank == RANK_7
-      && pawnFile != FILE_A
-      && file_of(strongRook) == pawnFile
-      && strongRook != queeningSquare
-      && (distance(strongKing, queeningSquare) < distance(weakKing, queeningSquare) - 2 + tempo)
-      && (distance(strongKing, queeningSquare) < distance(weakKing, strongRook) + tempo))
-      return ScaleFactor(SCALE_FACTOR_MAX - 2 * distance(strongKing, queeningSquare));
-
-  // Similar to the above, but with the pawn further back
-  if (   pawnFile != FILE_A
-      && file_of(strongRook) == pawnFile
-      && strongRook < strongPawn
-      && (distance(strongKing, queeningSquare) < distance(weakKing, queeningSquare) - 2 + tempo)
-      && (distance(strongKing, strongPawn + NORTH) < distance(weakKing, strongPawn + NORTH) - 2 + tempo)
-      && (  distance(weakKing, strongRook) + tempo >= 3
-          || (    distance(strongKing, queeningSquare) < distance(weakKing, strongRook) + tempo
-              && (distance(strongKing, strongPawn + NORTH) < distance(weakKing, strongPawn) + tempo))))
-      return ScaleFactor(  SCALE_FACTOR_MAX
-                         - 8 * distance(strongPawn, queeningSquare)
-                         - 2 * distance(strongKing, queeningSquare));
-
-  // If the pawn is not far advanced and the defending king is somewhere in
-  // the pawn's path, it's probably a draw.
-  if (pawnRank <= RANK_4 && weakKing > strongPawn)
-  {
-      if (file_of(weakKing) == file_of(strongPawn))
-          return ScaleFactor(10);
-      if (   distance<File>(weakKing, strongPawn) == 1
-          && distance(strongKing, weakKing) > 2)
-          return ScaleFactor(24 - 2 * distance(strongKing, weakKing));
-  }
-  return SCALE_FACTOR_NONE;
-}
-
-template<>
-ScaleFactor Endgame<KRPKB>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 1));
-  assert(verify_material(pos, weakSide, BishopValueMg, 0));
-
-  // Test for a rook pawn
-  if (pos.pieces(PAWN) & (FileABB | FileHBB))
-  {
-      Square weakKing = pos.square<KING>(weakSide);
-      Square weakBishop = pos.square<BISHOP>(weakSide);
-      Square strongKing = pos.square<KING>(strongSide);
-      Square strongPawn = pos.square<PAWN>(strongSide);
-      Rank pawnRank = relative_rank(strongSide, strongPawn);
-      Direction push = pawn_push(strongSide);
-
-      // If the pawn is on the 5th rank and the pawn (currently) is on
-      // the same color square as the bishop then there is a chance of
-      // a fortress. Depending on the king position give a moderate
-      // reduction or a stronger one if the defending king is near the
-      // corner but not trapped there.
-      if (pawnRank == RANK_5 && !opposite_colors(weakBishop, strongPawn))
-      {
-          int d = distance(strongPawn + 3 * push, weakKing);
-
-          if (d <= 2 && !(d == 0 && weakKing == strongKing + 2 * push))
-              return ScaleFactor(24);
-          else
-              return ScaleFactor(48);
-      }
-
-      // When the pawn has moved to the 6th rank we can be fairly sure
-      // it's drawn if the bishop attacks the square in front of the
-      // pawn from a reasonable distance and the defending king is near
-      // the corner
-      if (   pawnRank == RANK_6
-          && distance(strongPawn + 2 * push, weakKing) <= 1
-          && (attacks_bb<BISHOP>(weakBishop) & (strongPawn + push))
-          && distance<File>(weakBishop, strongPawn) >= 2)
-          return ScaleFactor(8);
-  }
-
-  return SCALE_FACTOR_NONE;
-}
-
-/// KRPP vs KRP. There is just a single rule: if the stronger side has no passed
-/// pawns and the defending king is actively placed, the position is drawish.
-template<>
-ScaleFactor Endgame<KRPPKRP>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, RookValueMg, 2));
-  assert(verify_material(pos, weakSide,   RookValueMg, 1));
-
-  Square strongPawn1 = lsb(pos.pieces(strongSide, PAWN));
-  Square strongPawn2 = msb(pos.pieces(strongSide, PAWN));
-  Square weakKing = pos.square<KING>(weakSide);
-
-  // Does the stronger side have a passed pawn?
-  if (pos.pawn_passed(strongSide, strongPawn1) || pos.pawn_passed(strongSide, strongPawn2))
-      return SCALE_FACTOR_NONE;
-
-  Rank pawnRank = std::max(relative_rank(strongSide, strongPawn1), relative_rank(strongSide, strongPawn2));
-
-  if (   distance<File>(weakKing, strongPawn1) <= 1
-      && distance<File>(weakKing, strongPawn2) <= 1
-      && relative_rank(strongSide, weakKing) > pawnRank)
-  {
-      assert(pawnRank > RANK_1 && pawnRank < RANK_7);
-      return ScaleFactor(7 * pawnRank);
-  }
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// K and two or more pawns vs K. There is just a single rule here: if all pawns
-/// are on the same rook file and are blocked by the defending king, it's a draw.
-template<>
-ScaleFactor Endgame<KPsK>::operator()(const Position& pos) const {
-
-  assert(pos.non_pawn_material(strongSide) == VALUE_ZERO);
-  assert(pos.count<PAWN>(strongSide) >= 2);
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
-
-  Square weakKing = pos.square<KING>(weakSide);
-  Bitboard strongPawns = pos.pieces(strongSide, PAWN);
-
-  // If all pawns are ahead of the king on a single rook file, it's a draw.
-  if (   !(strongPawns & ~(FileABB | FileHBB))
-      && !(strongPawns & ~passed_pawn_span(weakSide, weakKing)))
-      return SCALE_FACTOR_DRAW;
-
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// KBP vs KB. There are two rules: if the defending king is somewhere along the
-/// path of the pawn, and the square of the king is not of the same color as the
-/// stronger side's bishop, it's a draw. If the two bishops have opposite color,
-/// it's almost always a draw.
-template<>
-ScaleFactor Endgame<KBPKB>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, BishopValueMg, 1));
-  assert(verify_material(pos, weakSide,   BishopValueMg, 0));
-
-  Square strongPawn = pos.square<PAWN>(strongSide);
-  Square strongBishop = pos.square<BISHOP>(strongSide);
-  Square weakBishop = pos.square<BISHOP>(weakSide);
-  Square weakKing = pos.square<KING>(weakSide);
-
-  // Case 1: Defending king blocks the pawn, and cannot be driven away
-  if (   (forward_file_bb(strongSide, strongPawn) & weakKing)
-      && (   opposite_colors(weakKing, strongBishop)
-          || relative_rank(strongSide, weakKing) <= RANK_6))
-      return SCALE_FACTOR_DRAW;
-
-  // Case 2: Opposite colored bishops
-  if (opposite_colors(strongBishop, weakBishop))
-      return SCALE_FACTOR_DRAW;
-
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// KBPP vs KB. It detects a few basic draws with opposite-colored bishops
-template<>
-ScaleFactor Endgame<KBPPKB>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, BishopValueMg, 2));
-  assert(verify_material(pos, weakSide,   BishopValueMg, 0));
-
-  Square strongBishop = pos.square<BISHOP>(strongSide);
-  Square weakBishop   = pos.square<BISHOP>(weakSide);
-
-  if (!opposite_colors(strongBishop, weakBishop))
-      return SCALE_FACTOR_NONE;
-
-  Square weakKing = pos.square<KING>(weakSide);
-  Square strongPawn1 = lsb(pos.pieces(strongSide, PAWN));
-  Square strongPawn2 = msb(pos.pieces(strongSide, PAWN));
-  Square blockSq1, blockSq2;
-
-  if (relative_rank(strongSide, strongPawn1) > relative_rank(strongSide, strongPawn2))
-  {
-      blockSq1 = strongPawn1 + pawn_push(strongSide);
-      blockSq2 = make_square(file_of(strongPawn2), rank_of(strongPawn1));
-  }
-  else
-  {
-      blockSq1 = strongPawn2 + pawn_push(strongSide);
-      blockSq2 = make_square(file_of(strongPawn1), rank_of(strongPawn2));
-  }
-
-  switch (distance<File>(strongPawn1, strongPawn2))
-  {
-  case 0:
-    // Both pawns are on the same file. It's an easy draw if the defender firmly
-    // controls some square in the frontmost pawn's path.
-    if (   file_of(weakKing) == file_of(blockSq1)
-        && relative_rank(strongSide, weakKing) >= relative_rank(strongSide, blockSq1)
-        && opposite_colors(weakKing, strongBishop))
-        return SCALE_FACTOR_DRAW;
-    else
-        return SCALE_FACTOR_NONE;
-
-  case 1:
-    // Pawns on adjacent files. It's a draw if the defender firmly controls the
-    // square in front of the frontmost pawn's path, and the square diagonally
-    // behind this square on the file of the other pawn.
-    if (   weakKing == blockSq1
-        && opposite_colors(weakKing, strongBishop)
-        && (   weakBishop == blockSq2
-            || (attacks_bb<BISHOP>(blockSq2, pos.pieces()) & pos.pieces(weakSide, BISHOP))
-            || distance<Rank>(strongPawn1, strongPawn2) >= 2))
-        return SCALE_FACTOR_DRAW;
-
-    else if (   weakKing == blockSq2
-             && opposite_colors(weakKing, strongBishop)
-             && (   weakBishop == blockSq1
-                 || (attacks_bb<BISHOP>(blockSq1, pos.pieces()) & pos.pieces(weakSide, BISHOP))))
-        return SCALE_FACTOR_DRAW;
-    else
-        return SCALE_FACTOR_NONE;
-
-  default:
-    // The pawns are not on the same file or adjacent files. No scaling.
-    return SCALE_FACTOR_NONE;
-  }
-}
-
-
-/// KBP vs KN. There is a single rule: if the defending king is somewhere along
-/// the path of the pawn, and the square of the king is not of the same color as
-/// the stronger side's bishop, it's a draw.
-template<>
-ScaleFactor Endgame<KBPKN>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, BishopValueMg, 1));
-  assert(verify_material(pos, weakSide, KnightValueMg, 0));
-
-  Square strongPawn = pos.square<PAWN>(strongSide);
-  Square strongBishop = pos.square<BISHOP>(strongSide);
-  Square weakKing = pos.square<KING>(weakSide);
-
-  if (   file_of(weakKing) == file_of(strongPawn)
-      && relative_rank(strongSide, strongPawn) < relative_rank(strongSide, weakKing)
-      && (   opposite_colors(weakKing, strongBishop)
-          || relative_rank(strongSide, weakKing) <= RANK_6))
-      return SCALE_FACTOR_DRAW;
-
-  return SCALE_FACTOR_NONE;
-}
-
-
-/// KP vs KP. This is done by removing the weakest side's pawn and probing the
-/// KP vs K bitbase: if the weakest side has a draw without the pawn, it probably
-/// has at least a draw with the pawn as well. The exception is when the stronger
-/// side's pawn is far advanced and not on a rook file; in this case it is often
-/// possible to win (e.g. 8/4k3/3p4/3P4/6K1/8/8/8 w - - 0 1).
-template<>
-ScaleFactor Endgame<KPKP>::operator()(const Position& pos) const {
-
-  assert(verify_material(pos, strongSide, VALUE_ZERO, 1));
-  assert(verify_material(pos, weakSide,   VALUE_ZERO, 1));
-
-  // Assume strongSide is white and the pawn is on files A-D
-  Square strongKing = normalize(pos, strongSide, pos.square<KING>(strongSide));
-  Square weakKing   = normalize(pos, strongSide, pos.square<KING>(weakSide));
-  Square strongPawn = normalize(pos, strongSide, pos.square<PAWN>(strongSide));
-
-  Color us = strongSide == pos.side_to_move() ? WHITE : BLACK;
-
-  // If the pawn has advanced to the fifth rank or further, and is not a
-  // rook pawn, it's too dangerous to assume that it's at least a draw.
-  if (rank_of(strongPawn) >= RANK_5 && file_of(strongPawn) != FILE_A)
-      return SCALE_FACTOR_NONE;
-
-  // Probe the KPK bitbase with the weakest side's pawn removed. If it's a draw,
-  // it's probably at least a draw even with the pawn.
-  return Bitbases::probe(strongKing, strongPawn, weakKing, us) ? SCALE_FACTOR_NONE : SCALE_FACTOR_DRAW;
-}
-
-} // namespace Stockfish

src/endgame.h

@@ -1,126 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#ifndef ENDGAME_H_INCLUDED
-#define ENDGAME_H_INCLUDED
-
-#include <memory>
-#include <string>
-#include <type_traits>
-#include <unordered_map>
-#include <utility>
-
-#include "position.h"
-#include "types.h"
-
-namespace Stockfish {
-
-/// EndgameCode lists all supported endgame functions by corresponding codes
-
-enum EndgameCode {
-
-  EVALUATION_FUNCTIONS,
-  KNNK,  // KNN vs K
-  KNNKP, // KNN vs KP
-  KXK,   // Generic "mate lone king" eval
-  KBNK,  // KBN vs K
-  KPK,   // KP vs K
-  KRKP,  // KR vs KP
-  KRKB,  // KR vs KB
-  KRKN,  // KR vs KN
-  KQKP,  // KQ vs KP
-  KQKR,  // KQ vs KR
-
-  SCALING_FUNCTIONS,
-  KBPsK,   // KB and pawns vs K
-  KQKRPs,  // KQ vs KR and pawns
-  KRPKR,   // KRP vs KR
-  KRPKB,   // KRP vs KB
-  KRPPKRP, // KRPP vs KRP
-  KPsK,    // K and pawns vs K
-  KBPKB,   // KBP vs KB
-  KBPPKB,  // KBPP vs KB
-  KBPKN,   // KBP vs KN
-  KPKP     // KP vs KP
-};
-
-
-/// Endgame functions can be of two types depending on whether they return a
-/// Value or a ScaleFactor.
-
-template<EndgameCode E> using
-eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
-
-
-/// Base and derived functors for endgame evaluation and scaling functions
-
-template<typename T>
-struct EndgameBase {
-
-  explicit EndgameBase(Color c) : strongSide(c), weakSide(~c) {}
-  virtual ~EndgameBase() = default;
-  virtual T operator()(const Position&) const = 0;
-
-  const Color strongSide, weakSide;
-};
-
-
-template<EndgameCode E, typename T = eg_type<E>>
-struct Endgame : public EndgameBase<T> {
-
-  explicit Endgame(Color c) : EndgameBase<T>(c) {}
-  T operator()(const Position&) const override;
-};
-
-
-/// The Endgames namespace handles the pointers to endgame evaluation and scaling
-/// base objects in two std::map. We use polymorphism to invoke the actual
-/// endgame function by calling its virtual operator().
-
-namespace Endgames {
-
-  template<typename T> using Ptr = std::unique_ptr<EndgameBase<T>>;
-  template<typename T> using Map = std::unordered_map<Key, Ptr<T>>;
-
-  extern std::pair<Map<Value>, Map<ScaleFactor>> maps;
-
-  void init();
-
-  template<typename T>
-  Map<T>& map() {
-    return std::get<std::is_same<T, ScaleFactor>::value>(maps);
-  }
-
-  template<EndgameCode E, typename T = eg_type<E>>
-  void add(const std::string& code) {
-
-    StateInfo st;
-    map<T>()[Position().set(code, WHITE, &st).material_key()] = Ptr<T>(new Endgame<E>(WHITE));
-    map<T>()[Position().set(code, BLACK, &st).material_key()] = Ptr<T>(new Endgame<E>(BLACK));
-  }
-
-  template<typename T>
-  const EndgameBase<T>* probe(Key key) {
-    auto it = map<T>().find(key);
-    return it != map<T>().end() ? it->second.get() : nullptr;
-  }
-}
-
-} // namespace Stockfish
-
-#endif // #ifndef ENDGAME_H_INCLUDED

src/evaluate.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,36 +20,52 @@
 #define EVALUATE_H_INCLUDED
 
 #include <string>
-#include <optional>
+#include <unordered_map>
 
 #include "types.h"
 
 namespace Stockfish {
 
 class Position;
+class OptionsMap;
 
 namespace Eval {
 
-  std::string trace(Position& pos);
-  Value evaluate(const Position& pos);
+std::string trace(Position& pos);
 
-  extern bool useNNUE;
-  extern std::string currentEvalFileName;
+int   simple_eval(const Position& pos, Color c);
+Value evaluate(const Position& pos, int optimism);
 
-  // The default net name MUST follow the format nn-[SHA256 first 12 digits].nnue
-  // for the build process (profile-build and fishtest) to work. Do not change the
-  // name of the macro, as it is used in the Makefile.
-  #define EvalFileDefaultName   "nn-5af11540bbfe.nnue"
+// The default net name MUST follow the format nn-[SHA256 first 12 digits].nnue
+// for the build process (profile-build and fishtest) to work. Do not change the
+// name of the macro, as it is used in the Makefile.
+#define EvalFileDefaultNameBig "nn-b1a57edbea57.nnue"
+#define EvalFileDefaultNameSmall "nn-baff1ede1f90.nnue"
 
-  namespace NNUE {
+struct EvalFile {
+    // UCI option name
+    std::string optionName;
+    // Default net name, will use one of the macros above
+    std::string defaultName;
+    // Selected net name, either via uci option or default
+    std::string current;
+    // Net description extracted from the net file
+    std::string netDescription;
+};
 
-    void init();
-    void verify();
+namespace NNUE {
 
-  } // namespace NNUE
+enum NetSize : int;
 
-} // namespace Eval
+using EvalFiles = std::unordered_map<Eval::NNUE::NetSize, EvalFile>;
 
-} // namespace Stockfish
+EvalFiles load_networks(const std::string&, const OptionsMap&, EvalFiles);
+void      verify(const OptionsMap&, const EvalFiles&);
 
-#endif // #ifndef EVALUATE_H_INCLUDED
+}  // namespace NNUE
+
+}  // namespace Eval
+
+}  // namespace Stockfish
+
+#endif  // #ifndef EVALUATE_H_INCLUDED

src/incbin/incbin.h

@@ -3,8 +3,8 @@
  * @author Dale Weiler
  * @brief Utility for including binary files
  *
- * Facilities for including binary files into the current translation unit and
- * making use from them externally in other translation units.
+ * Facilities for including binary files into the current translation unit
+ * and making use of them externally in other translation units.
  */
 #ifndef INCBIN_HDR
 #define INCBIN_HDR
@@ -139,7 +139,7 @@
 #endif
 
 #if defined(__APPLE__)
-/* The directives are different for Apple branded compilers */
+/* The directives are different for Apple-branded compilers */
 #  define INCBIN_SECTION         INCBIN_OUTPUT_SECTION "\n"
 #  define INCBIN_GLOBAL(NAME)    ".globl " INCBIN_MANGLE INCBIN_STRINGIZE(INCBIN_PREFIX) #NAME "\n"
 #  define INCBIN_INT             ".long "
@@ -261,8 +261,8 @@
     INCBIN_STRINGIZE( \
         INCBIN_STYLE_IDENT(TYPE)) \
 
-/* Generate the global labels by indirectly invoking the macro with our style
- * type and concatenating the name against them. */
+/* Generate the global labels by indirectly invoking the macro
+ * with our style type and concatenate the name against them. */
 #define INCBIN_GLOBAL_LABELS(NAME, TYPE) \
     INCBIN_INVOKE( \
         INCBIN_GLOBAL, \

src/main.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,37 +17,32 @@
 */
 
 #include <iostream>
+#include <unordered_map>
 
 #include "bitboard.h"
-#include "endgame.h"
+#include "evaluate.h"
+#include "misc.h"
 #include "position.h"
-#include "psqt.h"
-#include "search.h"
-#include "syzygy/tbprobe.h"
-#include "thread.h"
-#include "tt.h"
+#include "tune.h"
+#include "types.h"
 #include "uci.h"
 
 using namespace Stockfish;
 
 int main(int argc, char* argv[]) {
 
-  std::cout << engine_info() << std::endl;
+    std::cout << engine_info() << std::endl;
 
-  CommandLine::init(argc, argv);
-  UCI::init(Options);
-  Tune::init();
-  PSQT::init();
-  Bitboards::init();
-  Position::init();
-  Bitbases::init();
-  Endgames::init();
-  Threads.set(size_t(Options["Threads"]));
-  Search::clear(); // After threads are up
-  Eval::NNUE::init();
+    Bitboards::init();
+    Position::init();
 
-  UCI::loop(argc, argv);
+    UCI uci(argc, argv);
 
-  Threads.set(0);
-  return 0;
+    Tune::init(uci.options);
+
+    uci.evalFiles = Eval::NNUE::load_networks(uci.workingDirectory(), uci.options, uci.evalFiles);
+
+    uci.loop();
+
+    return 0;
 }

src/material.cpp

@@ -1,229 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <cassert>
-#include <cstring>   // For std::memset
-
-#include "material.h"
-#include "thread.h"
-
-using namespace std;
-
-namespace Stockfish {
-
-namespace {
-  #define S(mg, eg) make_score(mg, eg)
-
-  // Polynomial material imbalance parameters
-
-  // One Score parameter for each pair (our piece, another of our pieces)
-  constexpr Score QuadraticOurs[][PIECE_TYPE_NB] = {
-    // OUR PIECE 2
-    // bishop pair    pawn         knight       bishop       rook           queen
-    {S(1419, 1455)                                                                  }, // Bishop pair
-    {S( 101,   28), S( 37,  39)                                                     }, // Pawn
-    {S(  57,   64), S(249, 187), S(-49, -62)                                        }, // Knight      OUR PIECE 1
-    {S(   0,    0), S(118, 137), S( 10,  27), S(  0,   0)                           }, // Bishop
-    {S( -63,  -68), S( -5,   3), S(100,  81), S(132, 118), S(-246, -244)            }, // Rook
-    {S(-210, -211), S( 37,  14), S(147, 141), S(161, 105), S(-158, -174), S(-9,-31) }  // Queen
-  };
-
-  // One Score parameter for each pair (our piece, their piece)
-  constexpr Score QuadraticTheirs[][PIECE_TYPE_NB] = {
-    // THEIR PIECE
-    // bishop pair   pawn         knight       bishop       rook         queen
-    {                                                                               }, // Bishop pair
-    {S(  33,  30)                                                                   }, // Pawn
-    {S(  46,  18), S(106,  84)                                                      }, // Knight      OUR PIECE
-    {S(  75,  35), S( 59,  44), S( 60,  15)                                         }, // Bishop
-    {S(  26,  35), S(  6,  22), S( 38,  39), S(-12,  -2)                            }, // Rook
-    {S(  97,  93), S(100, 163), S(-58, -91), S(112, 192), S(276, 225)               }  // Queen
-  };
-
-  #undef S
-
-  // Endgame evaluation and scaling functions are accessed directly and not through
-  // the function maps because they correspond to more than one material hash key.
-  Endgame<KXK>    EvaluateKXK[] = { Endgame<KXK>(WHITE),    Endgame<KXK>(BLACK) };
-
-  Endgame<KBPsK>  ScaleKBPsK[]  = { Endgame<KBPsK>(WHITE),  Endgame<KBPsK>(BLACK) };
-  Endgame<KQKRPs> ScaleKQKRPs[] = { Endgame<KQKRPs>(WHITE), Endgame<KQKRPs>(BLACK) };
-  Endgame<KPsK>   ScaleKPsK[]   = { Endgame<KPsK>(WHITE),   Endgame<KPsK>(BLACK) };
-  Endgame<KPKP>   ScaleKPKP[]   = { Endgame<KPKP>(WHITE),   Endgame<KPKP>(BLACK) };
-
-  // Helper used to detect a given material distribution
-  bool is_KXK(const Position& pos, Color us) {
-    return  !more_than_one(pos.pieces(~us))
-          && pos.non_pawn_material(us) >= RookValueMg;
-  }
-
-  bool is_KBPsK(const Position& pos, Color us) {
-    return   pos.non_pawn_material(us) == BishopValueMg
-          && pos.count<PAWN>(us) >= 1;
-  }
-
-  bool is_KQKRPs(const Position& pos, Color us) {
-    return  !pos.count<PAWN>(us)
-          && pos.non_pawn_material(us) == QueenValueMg
-          && pos.count<ROOK>(~us) == 1
-          && pos.count<PAWN>(~us) >= 1;
-  }
-
-
-  /// imbalance() calculates the imbalance by comparing the piece count of each
-  /// piece type for both colors.
-
-  template<Color Us>
-  Score imbalance(const int pieceCount[][PIECE_TYPE_NB]) {
-
-    constexpr Color Them = ~Us;
-
-    Score bonus = SCORE_ZERO;
-
-    // Second-degree polynomial material imbalance, by Tord Romstad
-    for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
-    {
-        if (!pieceCount[Us][pt1])
-            continue;
-
-        int v = QuadraticOurs[pt1][pt1] * pieceCount[Us][pt1];
-
-        for (int pt2 = NO_PIECE_TYPE; pt2 < pt1; ++pt2)
-            v +=  QuadraticOurs[pt1][pt2] * pieceCount[Us][pt2]
-                + QuadraticTheirs[pt1][pt2] * pieceCount[Them][pt2];
-
-        bonus += pieceCount[Us][pt1] * v;
-    }
-
-    return bonus;
-  }
-
-} // namespace
-
-namespace Material {
-
-
-/// Material::probe() looks up the current position's material configuration in
-/// the material hash table. It returns a pointer to the Entry if the position
-/// is found. Otherwise a new Entry is computed and stored there, so we don't
-/// have to recompute all when the same material configuration occurs again.
-
-Entry* probe(const Position& pos) {
-
-  Key key = pos.material_key();
-  Entry* e = pos.this_thread()->materialTable[key];
-
-  if (e->key == key)
-      return e;
-
-  std::memset(e, 0, sizeof(Entry));
-  e->key = key;
-  e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
-
-  Value npm_w = pos.non_pawn_material(WHITE);
-  Value npm_b = pos.non_pawn_material(BLACK);
-  Value npm   = std::clamp(npm_w + npm_b, EndgameLimit, MidgameLimit);
-
-  // Map total non-pawn material into [PHASE_ENDGAME, PHASE_MIDGAME]
-  e->gamePhase = Phase(((npm - EndgameLimit) * PHASE_MIDGAME) / (MidgameLimit - EndgameLimit));
-
-  // Let's look if we have a specialized evaluation function for this particular
-  // material configuration. Firstly we look for a fixed configuration one, then
-  // for a generic one if the previous search failed.
-  if ((e->evaluationFunction = Endgames::probe<Value>(key)) != nullptr)
-      return e;
-
-  for (Color c : { WHITE, BLACK })
-      if (is_KXK(pos, c))
-      {
-          e->evaluationFunction = &EvaluateKXK[c];
-          return e;
-      }
-
-  // OK, we didn't find any special evaluation function for the current material
-  // configuration. Is there a suitable specialized scaling function?
-  const auto* sf = Endgames::probe<ScaleFactor>(key);
-
-  if (sf)
-  {
-      e->scalingFunction[sf->strongSide] = sf; // Only strong color assigned
-      return e;
-  }
-
-  // We didn't find any specialized scaling function, so fall back on generic
-  // ones that refer to more than one material distribution. Note that in this
-  // case we don't return after setting the function.
-  for (Color c : { WHITE, BLACK })
-  {
-    if (is_KBPsK(pos, c))
-        e->scalingFunction[c] = &ScaleKBPsK[c];
-
-    else if (is_KQKRPs(pos, c))
-        e->scalingFunction[c] = &ScaleKQKRPs[c];
-  }
-
-  if (npm_w + npm_b == VALUE_ZERO && pos.pieces(PAWN)) // Only pawns on the board
-  {
-      if (!pos.count<PAWN>(BLACK))
-      {
-          assert(pos.count<PAWN>(WHITE) >= 2);
-
-          e->scalingFunction[WHITE] = &ScaleKPsK[WHITE];
-      }
-      else if (!pos.count<PAWN>(WHITE))
-      {
-          assert(pos.count<PAWN>(BLACK) >= 2);
-
-          e->scalingFunction[BLACK] = &ScaleKPsK[BLACK];
-      }
-      else if (pos.count<PAWN>(WHITE) == 1 && pos.count<PAWN>(BLACK) == 1)
-      {
-          // This is a special case because we set scaling functions
-          // for both colors instead of only one.
-          e->scalingFunction[WHITE] = &ScaleKPKP[WHITE];
-          e->scalingFunction[BLACK] = &ScaleKPKP[BLACK];
-      }
-  }
-
-  // Zero or just one pawn makes it difficult to win, even with a small material
-  // advantage. This catches some trivial draws like KK, KBK and KNK and gives a
-  // drawish scale factor for cases such as KRKBP and KmmKm (except for KBBKN).
-  if (!pos.count<PAWN>(WHITE) && npm_w - npm_b <= BishopValueMg)
-      e->factor[WHITE] = uint8_t(npm_w <  RookValueMg   ? SCALE_FACTOR_DRAW :
-                                 npm_b <= BishopValueMg ? 4 : 14);
-
-  if (!pos.count<PAWN>(BLACK) && npm_b - npm_w <= BishopValueMg)
-      e->factor[BLACK] = uint8_t(npm_b <  RookValueMg   ? SCALE_FACTOR_DRAW :
-                                 npm_w <= BishopValueMg ? 4 : 14);
-
-  // Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder
-  // for the bishop pair "extended piece", which allows us to be more flexible
-  // in defining bishop pair bonuses.
-  const int pieceCount[COLOR_NB][PIECE_TYPE_NB] = {
-  { pos.count<BISHOP>(WHITE) > 1, pos.count<PAWN>(WHITE), pos.count<KNIGHT>(WHITE),
-    pos.count<BISHOP>(WHITE)    , pos.count<ROOK>(WHITE), pos.count<QUEEN >(WHITE) },
-  { pos.count<BISHOP>(BLACK) > 1, pos.count<PAWN>(BLACK), pos.count<KNIGHT>(BLACK),
-    pos.count<BISHOP>(BLACK)    , pos.count<ROOK>(BLACK), pos.count<QUEEN >(BLACK) } };
-
-  e->score = (imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16;
-  return e;
-}
-
-} // namespace Material
-
-} // namespace Stockfish

src/material.h

@@ -1,71 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#ifndef MATERIAL_H_INCLUDED
-#define MATERIAL_H_INCLUDED
-
-#include "endgame.h"
-#include "misc.h"
-#include "position.h"
-#include "types.h"
-
-namespace Stockfish::Material {
-
-/// Material::Entry contains various information about a material configuration.
-/// It contains a material imbalance evaluation, a function pointer to a special
-/// endgame evaluation function (which in most cases is nullptr, meaning that the
-/// standard evaluation function will be used), and scale factors.
-///
-/// The scale factors are used to scale the evaluation score up or down. For
-/// instance, in KRB vs KR endgames, the score is scaled down by a factor of 4,
-/// which will result in scores of absolute value less than one pawn.
-
-struct Entry {
-
-  Score imbalance() const { return score; }
-  Phase game_phase() const { return (Phase)gamePhase; }
-  bool specialized_eval_exists() const { return evaluationFunction != nullptr; }
-  Value evaluate(const Position& pos) const { return (*evaluationFunction)(pos); }
-
-  // scale_factor() takes a position and a color as input and returns a scale factor
-  // for the given color. We have to provide the position in addition to the color
-  // because the scale factor may also be a function which should be applied to
-  // the position. For instance, in KBP vs K endgames, the scaling function looks
-  // for rook pawns and wrong-colored bishops.
-  ScaleFactor scale_factor(const Position& pos, Color c) const {
-    ScaleFactor sf = scalingFunction[c] ? (*scalingFunction[c])(pos)
-                                        :  SCALE_FACTOR_NONE;
-    return sf != SCALE_FACTOR_NONE ? sf : ScaleFactor(factor[c]);
-  }
-
-  Key key;
-  const EndgameBase<Value>* evaluationFunction;
-  const EndgameBase<ScaleFactor>* scalingFunction[COLOR_NB]; // Could be one for each
-                                                             // side (e.g. KPKP, KBPsK)
-  Score score;
-  int16_t gamePhase;
-  uint8_t factor[COLOR_NB];
-};
-
-using Table = HashTable<Entry, 8192>;
-
-Entry* probe(const Position& pos);
-
-} // namespace Stockfish::Material
-
-#endif // #ifndef MATERIAL_H_INCLUDED

src/misc.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,14 +19,14 @@
 #ifndef MISC_H_INCLUDED
 #define MISC_H_INCLUDED
 
+#include <algorithm>
 #include <cassert>
 #include <chrono>
-#include <ostream>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
 #include <string>
 #include <vector>
-#include <cstdint>
-
-#include "types.h"
 
 #define stringify2(x) #x
 #define stringify(x) stringify2(x)
@@ -35,12 +35,19 @@ namespace Stockfish {
 
 std::string engine_info(bool to_uci = false);
 std::string compiler_info();
+
+// Preloads the given address in L1/L2 cache. This is a non-blocking
+// function that doesn't stall the CPU waiting for data to be loaded from memory,
+// which can be quite slow.
 void prefetch(void* addr);
-void start_logger(const std::string& fname);
+
+void  start_logger(const std::string& fname);
 void* std_aligned_alloc(size_t alignment, size_t size);
-void std_aligned_free(void* ptr);
-void* aligned_large_pages_alloc(size_t size); // memory aligned by page size, min alignment: 4096 bytes
-void aligned_large_pages_free(void* mem); // nop if mem == nullptr
+void  std_aligned_free(void* ptr);
+// memory aligned by page size, min alignment: 4096 bytes
+void* aligned_large_pages_alloc(size_t size);
+// nop if mem == nullptr
+void aligned_large_pages_free(void* mem);
 
 void dbg_hit_on(bool cond, int slot = 0);
 void dbg_mean_of(int64_t value, int slot = 0);
@@ -48,129 +55,154 @@ void dbg_stdev_of(int64_t value, int slot = 0);
 void dbg_correl_of(int64_t value1, int64_t value2, int slot = 0);
 void dbg_print();
 
-using TimePoint = std::chrono::milliseconds::rep; // A value in milliseconds
+using TimePoint = std::chrono::milliseconds::rep;  // A value in milliseconds
 static_assert(sizeof(TimePoint) == sizeof(int64_t), "TimePoint should be 64 bits");
 inline TimePoint now() {
-  return std::chrono::duration_cast<std::chrono::milliseconds>
-        (std::chrono::steady_clock::now().time_since_epoch()).count();
+    return std::chrono::duration_cast<std::chrono::milliseconds>(
+             std::chrono::steady_clock::now().time_since_epoch())
+      .count();
 }
 
-template<class Entry, int Size>
-struct HashTable {
-  Entry* operator[](Key key) { return &table[(uint32_t)key & (Size - 1)]; }
 
-private:
-  std::vector<Entry> table = std::vector<Entry>(Size); // Allocate on the heap
+enum SyncCout {
+    IO_LOCK,
+    IO_UNLOCK
 };
-
-
-enum SyncCout { IO_LOCK, IO_UNLOCK };
 std::ostream& operator<<(std::ostream&, SyncCout);
 
 #define sync_cout std::cout << IO_LOCK
 #define sync_endl std::endl << IO_UNLOCK
 
 
-// align_ptr_up() : get the first aligned element of an array.
+// Get the first aligned element of an array.
 // ptr must point to an array of size at least `sizeof(T) * N + alignment` bytes,
 // where N is the number of elements in the array.
-template <uintptr_t Alignment, typename T>
-T* align_ptr_up(T* ptr)
-{
-  static_assert(alignof(T) < Alignment);
+template<uintptr_t Alignment, typename T>
+T* align_ptr_up(T* ptr) {
+    static_assert(alignof(T) < Alignment);
 
-  const uintptr_t ptrint = reinterpret_cast<uintptr_t>(reinterpret_cast<char*>(ptr));
-  return reinterpret_cast<T*>(reinterpret_cast<char*>((ptrint + (Alignment - 1)) / Alignment * Alignment));
+    const uintptr_t ptrint = reinterpret_cast<uintptr_t>(reinterpret_cast<char*>(ptr));
+    return reinterpret_cast<T*>(
+      reinterpret_cast<char*>((ptrint + (Alignment - 1)) / Alignment * Alignment));
 }
 
 
-// IsLittleEndian : true if and only if the binary is compiled on a little endian machine
-static inline const union { uint32_t i; char c[4]; } Le = { 0x01020304 };
+// True if and only if the binary is compiled on a little-endian machine
+static inline const union {
+    uint32_t i;
+    char     c[4];
+} Le                                    = {0x01020304};
 static inline const bool IsLittleEndian = (Le.c[0] == 4);
 
 
-template <typename T, std::size_t MaxSize>
+template<typename T, std::size_t MaxSize>
 class ValueList {
 
-public:
-  std::size_t size() const { return size_; }
-  void push_back(const T& value) { values_[size_++] = value; }
-  const T* begin() const { return values_; }
-  const T* end() const { return values_ + size_; }
+   public:
+    std::size_t size() const { return size_; }
+    void        push_back(const T& value) { values_[size_++] = value; }
+    const T*    begin() const { return values_; }
+    const T*    end() const { return values_ + size_; }
+    const T&    operator[](int index) const { return values_[index]; }
 
-private:
-  T values_[MaxSize];
-  std::size_t size_ = 0;
+   private:
+    T           values_[MaxSize];
+    std::size_t size_ = 0;
 };
 
 
-/// xorshift64star Pseudo-Random Number Generator
-/// This class is based on original code written and dedicated
-/// to the public domain by Sebastiano Vigna (2014).
-/// It has the following characteristics:
-///
-///  -  Outputs 64-bit numbers
-///  -  Passes Dieharder and SmallCrush test batteries
-///  -  Does not require warm-up, no zeroland to escape
-///  -  Internal state is a single 64-bit integer
-///  -  Period is 2^64 - 1
-///  -  Speed: 1.60 ns/call (Core i7 @3.40GHz)
-///
-/// For further analysis see
-///   <http://vigna.di.unimi.it/ftp/papers/xorshift.pdf>
+// xorshift64star Pseudo-Random Number Generator
+// This class is based on original code written and dedicated
+// to the public domain by Sebastiano Vigna (2014).
+// It has the following characteristics:
+//
+//  -  Outputs 64-bit numbers
+//  -  Passes Dieharder and SmallCrush test batteries
+//  -  Does not require warm-up, no zeroland to escape
+//  -  Internal state is a single 64-bit integer
+//  -  Period is 2^64 - 1
+//  -  Speed: 1.60 ns/call (Core i7 @3.40GHz)
+//
+// For further analysis see
+//   <http://vigna.di.unimi.it/ftp/papers/xorshift.pdf>
 
 class PRNG {
 
-  uint64_t s;
+    uint64_t s;
 
-  uint64_t rand64() {
+    uint64_t rand64() {
 
-    s ^= s >> 12, s ^= s << 25, s ^= s >> 27;
-    return s * 2685821657736338717LL;
-  }
+        s ^= s >> 12, s ^= s << 25, s ^= s >> 27;
+        return s * 2685821657736338717LL;
+    }
 
-public:
-  PRNG(uint64_t seed) : s(seed) { assert(seed); }
+   public:
+    PRNG(uint64_t seed) :
+        s(seed) {
+        assert(seed);
+    }
 
-  template<typename T> T rand() { return T(rand64()); }
+    template<typename T>
+    T rand() {
+        return T(rand64());
+    }
 
-  /// Special generator used to fast init magic numbers.
-  /// Output values only have 1/8th of their bits set on average.
-  template<typename T> T sparse_rand()
-  { return T(rand64() & rand64() & rand64()); }
+    // Special generator used to fast init magic numbers.
+    // Output values only have 1/8th of their bits set on average.
+    template<typename T>
+    T sparse_rand() {
+        return T(rand64() & rand64() & rand64());
+    }
 };
 
 inline uint64_t mul_hi64(uint64_t a, uint64_t b) {
 #if defined(__GNUC__) && defined(IS_64BIT)
     __extension__ using uint128 = unsigned __int128;
-    return ((uint128)a * (uint128)b) >> 64;
+    return (uint128(a) * uint128(b)) >> 64;
 #else
-    uint64_t aL = (uint32_t)a, aH = a >> 32;
-    uint64_t bL = (uint32_t)b, bH = b >> 32;
+    uint64_t aL = uint32_t(a), aH = a >> 32;
+    uint64_t bL = uint32_t(b), bH = b >> 32;
     uint64_t c1 = (aL * bL) >> 32;
     uint64_t c2 = aH * bL + c1;
-    uint64_t c3 = aL * bH + (uint32_t)c2;
+    uint64_t c3 = aL * bH + uint32_t(c2);
     return aH * bH + (c2 >> 32) + (c3 >> 32);
 #endif
 }
 
-/// Under Windows it is not possible for a process to run on more than one
-/// logical processor group. This usually means to be limited to use max 64
-/// cores. To overcome this, some special platform specific API should be
-/// called to set group affinity for each thread. Original code from Texel by
-/// Peter Österlund.
-
+// Under Windows it is not possible for a process to run on more than one
+// logical processor group. This usually means being limited to using max 64
+// cores. To overcome this, some special platform-specific API should be
+// called to set group affinity for each thread. Original code from Texel by
+// Peter Österlund.
 namespace WinProcGroup {
-  void bindThisThread(size_t idx);
+void bindThisThread(size_t idx);
 }
 
-namespace CommandLine {
-  void init(int argc, char* argv[]);
 
-  extern std::string binaryDirectory;  // path of the executable directory
-  extern std::string workingDirectory; // path of the working directory
+struct CommandLine {
+   public:
+    CommandLine(int, char**);
+
+    int    argc;
+    char** argv;
+
+    std::string binaryDirectory;   // path of the executable directory
+    std::string workingDirectory;  // path of the working directory
+};
+
+namespace Utility {
+
+template<typename T, typename Predicate>
+void move_to_front(std::vector<T>& vec, Predicate pred) {
+    auto it = std::find_if(vec.begin(), vec.end(), pred);
+
+    if (it != vec.end())
+    {
+        std::rotate(vec.begin(), it, it + 1);
+    }
+}
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#endif // #ifndef MISC_H_INCLUDED
+#endif  // #ifndef MISC_H_INCLUDED

src/movegen.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,64 +16,60 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <cassert>
-
 #include "movegen.h"
+
+#include <cassert>
+#include <initializer_list>
+
+#include "bitboard.h"
 #include "position.h"
 
 namespace Stockfish {
 
 namespace {
 
-  template<GenType Type, Direction D, bool Enemy>
-  ExtMove* make_promotions(ExtMove* moveList, [[maybe_unused]] Square to) {
+template<GenType Type, Direction D, bool Enemy>
+ExtMove* make_promotions(ExtMove* moveList, [[maybe_unused]] Square to) {
 
-    if constexpr (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
-    {
-        *moveList++ = make<PROMOTION>(to - D, to, QUEEN);
-        if constexpr (Enemy && Type == CAPTURES)
-        {
-            *moveList++ = make<PROMOTION>(to - D, to, ROOK);
-            *moveList++ = make<PROMOTION>(to - D, to, BISHOP);
-            *moveList++ = make<PROMOTION>(to - D, to, KNIGHT);
-        }
-    }
+    constexpr bool all = Type == EVASIONS || Type == NON_EVASIONS;
 
-    if constexpr ((Type == QUIETS && !Enemy) || Type == EVASIONS || Type == NON_EVASIONS)
+    if constexpr (Type == CAPTURES || all)
+        *moveList++ = Move::make<PROMOTION>(to - D, to, QUEEN);
+
+    if constexpr ((Type == CAPTURES && Enemy) || (Type == QUIETS && !Enemy) || all)
     {
-        *moveList++ = make<PROMOTION>(to - D, to, ROOK);
-        *moveList++ = make<PROMOTION>(to - D, to, BISHOP);
-        *moveList++ = make<PROMOTION>(to - D, to, KNIGHT);
+        *moveList++ = Move::make<PROMOTION>(to - D, to, ROOK);
+        *moveList++ = Move::make<PROMOTION>(to - D, to, BISHOP);
+        *moveList++ = Move::make<PROMOTION>(to - D, to, KNIGHT);
     }
 
     return moveList;
-  }
+}
 
 
-  template<Color Us, GenType Type>
-  ExtMove* generate_pawn_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
+template<Color Us, GenType Type>
+ExtMove* generate_pawn_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
 
     constexpr Color     Them     = ~Us;
-    constexpr Bitboard  TRank7BB = (Us == WHITE ? Rank7BB    : Rank2BB);
-    constexpr Bitboard  TRank3BB = (Us == WHITE ? Rank3BB    : Rank6BB);
+    constexpr Bitboard  TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB);
+    constexpr Bitboard  TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
     constexpr Direction Up       = pawn_push(Us);
     constexpr Direction UpRight  = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
     constexpr Direction UpLeft   = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
 
     const Bitboard emptySquares = ~pos.pieces();
-    const Bitboard enemies      =  Type == EVASIONS ? pos.checkers()
-                                                    : pos.pieces(Them);
+    const Bitboard enemies      = Type == EVASIONS ? pos.checkers() : pos.pieces(Them);
 
-    Bitboard pawnsOn7    = pos.pieces(Us, PAWN) &  TRank7BB;
+    Bitboard pawnsOn7    = pos.pieces(Us, PAWN) & TRank7BB;
     Bitboard pawnsNotOn7 = pos.pieces(Us, PAWN) & ~TRank7BB;
 
     // Single and double pawn pushes, no promotions
     if constexpr (Type != CAPTURES)
     {
-        Bitboard b1 = shift<Up>(pawnsNotOn7)   & emptySquares;
+        Bitboard b1 = shift<Up>(pawnsNotOn7) & emptySquares;
         Bitboard b2 = shift<Up>(b1 & TRank3BB) & emptySquares;
 
-        if constexpr (Type == EVASIONS) // Consider only blocking squares
+        if constexpr (Type == EVASIONS)  // Consider only blocking squares
         {
             b1 &= target;
             b2 &= target;
@@ -84,22 +80,22 @@ namespace {
             // To make a quiet check, you either make a direct check by pushing a pawn
             // or push a blocker pawn that is not on the same file as the enemy king.
             // Discovered check promotion has been already generated amongst the captures.
-            Square ksq = pos.square<KING>(Them);
+            Square   ksq              = pos.square<KING>(Them);
             Bitboard dcCandidatePawns = pos.blockers_for_king(Them) & ~file_bb(ksq);
-            b1 &= pawn_attacks_bb(Them, ksq) | shift<   Up>(dcCandidatePawns);
-            b2 &= pawn_attacks_bb(Them, ksq) | shift<Up+Up>(dcCandidatePawns);
+            b1 &= pawn_attacks_bb(Them, ksq) | shift<Up>(dcCandidatePawns);
+            b2 &= pawn_attacks_bb(Them, ksq) | shift<Up + Up>(dcCandidatePawns);
         }
 
         while (b1)
         {
-            Square to = pop_lsb(b1);
-            *moveList++ = make_move(to - Up, to);
+            Square to   = pop_lsb(b1);
+            *moveList++ = Move(to - Up, to);
         }
 
         while (b2)
         {
-            Square to = pop_lsb(b2);
-            *moveList++ = make_move(to - Up - Up, to);
+            Square to   = pop_lsb(b2);
+            *moveList++ = Move(to - Up - Up, to);
         }
     }
 
@@ -107,8 +103,8 @@ namespace {
     if (pawnsOn7)
     {
         Bitboard b1 = shift<UpRight>(pawnsOn7) & enemies;
-        Bitboard b2 = shift<UpLeft >(pawnsOn7) & enemies;
-        Bitboard b3 = shift<Up     >(pawnsOn7) & emptySquares;
+        Bitboard b2 = shift<UpLeft>(pawnsOn7) & enemies;
+        Bitboard b3 = shift<Up>(pawnsOn7) & emptySquares;
 
         if constexpr (Type == EVASIONS)
             b3 &= target;
@@ -120,25 +116,25 @@ namespace {
             moveList = make_promotions<Type, UpLeft, true>(moveList, pop_lsb(b2));
 
         while (b3)
-            moveList = make_promotions<Type, Up,    false>(moveList, pop_lsb(b3));
+            moveList = make_promotions<Type, Up, false>(moveList, pop_lsb(b3));
     }
 
     // Standard and en passant captures
     if constexpr (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
     {
         Bitboard b1 = shift<UpRight>(pawnsNotOn7) & enemies;
-        Bitboard b2 = shift<UpLeft >(pawnsNotOn7) & enemies;
+        Bitboard b2 = shift<UpLeft>(pawnsNotOn7) & enemies;
 
         while (b1)
         {
-            Square to = pop_lsb(b1);
-            *moveList++ = make_move(to - UpRight, to);
+            Square to   = pop_lsb(b1);
+            *moveList++ = Move(to - UpRight, to);
         }
 
         while (b2)
         {
-            Square to = pop_lsb(b2);
-            *moveList++ = make_move(to - UpLeft, to);
+            Square to   = pop_lsb(b2);
+            *moveList++ = Move(to - UpLeft, to);
         }
 
         if (pos.ep_square() != SQ_NONE)
@@ -154,16 +150,16 @@ namespace {
             assert(b1);
 
             while (b1)
-                *moveList++ = make<EN_PASSANT>(pop_lsb(b1), pos.ep_square());
+                *moveList++ = Move::make<EN_PASSANT>(pop_lsb(b1), pos.ep_square());
         }
     }
 
     return moveList;
-  }
+}
 
 
-  template<Color Us, PieceType Pt, bool Checks>
-  ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
+template<Color Us, PieceType Pt, bool Checks>
+ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
 
     static_assert(Pt != KING && Pt != PAWN, "Unsupported piece type in generate_moves()");
 
@@ -171,43 +167,43 @@ namespace {
 
     while (bb)
     {
-        Square from = pop_lsb(bb);
-        Bitboard b = attacks_bb<Pt>(from, pos.pieces()) & target;
+        Square   from = pop_lsb(bb);
+        Bitboard b    = attacks_bb<Pt>(from, pos.pieces()) & target;
 
         // To check, you either move freely a blocker or make a direct check.
         if (Checks && (Pt == QUEEN || !(pos.blockers_for_king(~Us) & from)))
             b &= pos.check_squares(Pt);
 
         while (b)
-            *moveList++ = make_move(from, pop_lsb(b));
+            *moveList++ = Move(from, pop_lsb(b));
     }
 
     return moveList;
-  }
+}
 
 
-  template<Color Us, GenType Type>
-  ExtMove* generate_all(const Position& pos, ExtMove* moveList) {
+template<Color Us, GenType Type>
+ExtMove* generate_all(const Position& pos, ExtMove* moveList) {
 
     static_assert(Type != LEGAL, "Unsupported type in generate_all()");
 
-    constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantiations
-    const Square ksq = pos.square<KING>(Us);
-    Bitboard target;
+    constexpr bool Checks = Type == QUIET_CHECKS;  // Reduce template instantiations
+    const Square   ksq    = pos.square<KING>(Us);
+    Bitboard       target;
 
     // Skip generating non-king moves when in double check
     if (Type != EVASIONS || !more_than_one(pos.checkers()))
     {
-        target = Type == EVASIONS     ?  between_bb(ksq, lsb(pos.checkers()))
-               : Type == NON_EVASIONS ? ~pos.pieces( Us)
-               : Type == CAPTURES     ?  pos.pieces(~Us)
-                                      : ~pos.pieces(   ); // QUIETS || QUIET_CHECKS
+        target = Type == EVASIONS     ? between_bb(ksq, lsb(pos.checkers()))
+               : Type == NON_EVASIONS ? ~pos.pieces(Us)
+               : Type == CAPTURES     ? pos.pieces(~Us)
+                                      : ~pos.pieces();  // QUIETS || QUIET_CHECKS
 
         moveList = generate_pawn_moves<Us, Type>(pos, moveList, target);
         moveList = generate_moves<Us, KNIGHT, Checks>(pos, moveList, target);
         moveList = generate_moves<Us, BISHOP, Checks>(pos, moveList, target);
-        moveList = generate_moves<Us,   ROOK, Checks>(pos, moveList, target);
-        moveList = generate_moves<Us,  QUEEN, Checks>(pos, moveList, target);
+        moveList = generate_moves<Us, ROOK, Checks>(pos, moveList, target);
+        moveList = generate_moves<Us, QUEEN, Checks>(pos, moveList, target);
     }
 
     if (!Checks || pos.blockers_for_king(~Us) & ksq)
@@ -217,38 +213,38 @@ namespace {
             b &= ~attacks_bb<QUEEN>(pos.square<KING>(~Us));
 
         while (b)
-            *moveList++ = make_move(ksq, pop_lsb(b));
+            *moveList++ = Move(ksq, pop_lsb(b));
 
         if ((Type == QUIETS || Type == NON_EVASIONS) && pos.can_castle(Us & ANY_CASTLING))
-            for (CastlingRights cr : { Us & KING_SIDE, Us & QUEEN_SIDE } )
+            for (CastlingRights cr : {Us & KING_SIDE, Us & QUEEN_SIDE})
                 if (!pos.castling_impeded(cr) && pos.can_castle(cr))
-                    *moveList++ = make<CASTLING>(ksq, pos.castling_rook_square(cr));
+                    *moveList++ = Move::make<CASTLING>(ksq, pos.castling_rook_square(cr));
     }
 
     return moveList;
-  }
+}
 
-} // namespace
+}  // namespace
 
 
-/// <CAPTURES>     Generates all pseudo-legal captures plus queen promotions
-/// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions
-/// <EVASIONS>     Generates all pseudo-legal check evasions when the side to move is in check
-/// <QUIET_CHECKS> Generates all pseudo-legal non-captures giving check, except castling and promotions
-/// <NON_EVASIONS> Generates all pseudo-legal captures and non-captures
-///
-/// Returns a pointer to the end of the move list.
-
+// <CAPTURES>     Generates all pseudo-legal captures plus queen promotions
+// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions
+// <EVASIONS>     Generates all pseudo-legal check evasions
+// <NON_EVASIONS> Generates all pseudo-legal captures and non-captures
+// <QUIET_CHECKS> Generates all pseudo-legal non-captures giving check,
+//                except castling and promotions
+//
+// Returns a pointer to the end of the move list.
 template<GenType Type>
 ExtMove* generate(const Position& pos, ExtMove* moveList) {
 
-  static_assert(Type != LEGAL, "Unsupported type in generate()");
-  assert((Type == EVASIONS) == (bool)pos.checkers());
+    static_assert(Type != LEGAL, "Unsupported type in generate()");
+    assert((Type == EVASIONS) == bool(pos.checkers()));
 
-  Color us = pos.side_to_move();
+    Color us = pos.side_to_move();
 
-  return us == WHITE ? generate_all<WHITE, Type>(pos, moveList)
-                     : generate_all<BLACK, Type>(pos, moveList);
+    return us == WHITE ? generate_all<WHITE, Type>(pos, moveList)
+                       : generate_all<BLACK, Type>(pos, moveList);
 }
 
 // Explicit template instantiations
@@ -259,26 +255,26 @@ template ExtMove* generate<QUIET_CHECKS>(const Position&, ExtMove*);
 template ExtMove* generate<NON_EVASIONS>(const Position&, ExtMove*);
 
 
-/// generate<LEGAL> generates all the legal moves in the given position
+// generate<LEGAL> generates all the legal moves in the given position
 
 template<>
 ExtMove* generate<LEGAL>(const Position& pos, ExtMove* moveList) {
 
-  Color us = pos.side_to_move();
-  Bitboard pinned = pos.blockers_for_king(us) & pos.pieces(us);
-  Square ksq = pos.square<KING>(us);
-  ExtMove* cur = moveList;
+    Color    us     = pos.side_to_move();
+    Bitboard pinned = pos.blockers_for_king(us) & pos.pieces(us);
+    Square   ksq    = pos.square<KING>(us);
+    ExtMove* cur    = moveList;
 
-  moveList = pos.checkers() ? generate<EVASIONS    >(pos, moveList)
-                            : generate<NON_EVASIONS>(pos, moveList);
-  while (cur != moveList)
-      if (  ((pinned & from_sq(*cur)) || from_sq(*cur) == ksq || type_of(*cur) == EN_PASSANT)
-          && !pos.legal(*cur))
-          *cur = (--moveList)->move;
-      else
-          ++cur;
+    moveList =
+      pos.checkers() ? generate<EVASIONS>(pos, moveList) : generate<NON_EVASIONS>(pos, moveList);
+    while (cur != moveList)
+        if (((pinned & cur->from_sq()) || cur->from_sq() == ksq || cur->type_of() == EN_PASSANT)
+            && !pos.legal(*cur))
+            *cur = *(--moveList);
+        else
+            ++cur;
 
-  return moveList;
+    return moveList;
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/movegen.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,7 +19,8 @@
 #ifndef MOVEGEN_H_INCLUDED
 #define MOVEGEN_H_INCLUDED
 
-#include <algorithm>
+#include <algorithm>  // IWYU pragma: keep
+#include <cstddef>
 
 #include "types.h"
 
@@ -28,50 +29,46 @@ namespace Stockfish {
 class Position;
 
 enum GenType {
-  CAPTURES,
-  QUIETS,
-  QUIET_CHECKS,
-  EVASIONS,
-  NON_EVASIONS,
-  LEGAL
+    CAPTURES,
+    QUIETS,
+    QUIET_CHECKS,
+    EVASIONS,
+    NON_EVASIONS,
+    LEGAL
 };
 
-struct ExtMove {
-  Move move;
-  int value;
+struct ExtMove: public Move {
+    int value;
 
-  operator Move() const { return move; }
-  void operator=(Move m) { move = m; }
+    void operator=(Move m) { data = m.raw(); }
 
-  // Inhibit unwanted implicit conversions to Move
-  // with an ambiguity that yields to a compile error.
-  operator float() const = delete;
+    // Inhibit unwanted implicit conversions to Move
+    // with an ambiguity that yields to a compile error.
+    operator float() const = delete;
 };
 
-inline bool operator<(const ExtMove& f, const ExtMove& s) {
-  return f.value < s.value;
-}
+inline bool operator<(const ExtMove& f, const ExtMove& s) { return f.value < s.value; }
 
 template<GenType>
 ExtMove* generate(const Position& pos, ExtMove* moveList);
 
-/// The MoveList struct is a simple wrapper around generate(). It sometimes comes
-/// in handy to use this class instead of the low level generate() function.
+// The MoveList struct wraps the generate() function and returns a convenient
+// list of moves. Using MoveList is sometimes preferable to directly calling
+// the lower level generate() function.
 template<GenType T>
 struct MoveList {
 
-  explicit MoveList(const Position& pos) : last(generate<T>(pos, moveList)) {}
-  const ExtMove* begin() const { return moveList; }
-  const ExtMove* end() const { return last; }
-  size_t size() const { return last - moveList; }
-  bool contains(Move move) const {
-    return std::find(begin(), end(), move) != end();
-  }
+    explicit MoveList(const Position& pos) :
+        last(generate<T>(pos, moveList)) {}
+    const ExtMove* begin() const { return moveList; }
+    const ExtMove* end() const { return last; }
+    size_t         size() const { return last - moveList; }
+    bool           contains(Move move) const { return std::find(begin(), end(), move) != end(); }
 
-private:
-  ExtMove moveList[MAX_MOVES], *last;
+   private:
+    ExtMove moveList[MAX_MOVES], *last;
 };
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#endif // #ifndef MOVEGEN_H_INCLUDED
+#endif  // #ifndef MOVEGEN_H_INCLUDED

src/movepick.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,280 +16,371 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "movepick.h"
+
+#include <algorithm>
 #include <cassert>
+#include <iterator>
+#include <utility>
 
 #include "bitboard.h"
-#include "movepick.h"
+#include "position.h"
 
 namespace Stockfish {
 
 namespace {
 
-  enum Stages {
-    MAIN_TT, CAPTURE_INIT, GOOD_CAPTURE, REFUTATION, QUIET_INIT, QUIET, BAD_CAPTURE,
-    EVASION_TT, EVASION_INIT, EVASION,
-    PROBCUT_TT, PROBCUT_INIT, PROBCUT,
-    QSEARCH_TT, QCAPTURE_INIT, QCAPTURE, QCHECK_INIT, QCHECK
-  };
+enum Stages {
+    // generate main search moves
+    MAIN_TT,
+    CAPTURE_INIT,
+    GOOD_CAPTURE,
+    REFUTATION,
+    QUIET_INIT,
+    GOOD_QUIET,
+    BAD_CAPTURE,
+    BAD_QUIET,
 
-  // partial_insertion_sort() sorts moves in descending order up to and including
-  // a given limit. The order of moves smaller than the limit is left unspecified.
-  void partial_insertion_sort(ExtMove* begin, ExtMove* end, int limit) {
+    // generate evasion moves
+    EVASION_TT,
+    EVASION_INIT,
+    EVASION,
+
+    // generate probcut moves
+    PROBCUT_TT,
+    PROBCUT_INIT,
+    PROBCUT,
+
+    // generate qsearch moves
+    QSEARCH_TT,
+    QCAPTURE_INIT,
+    QCAPTURE,
+    QCHECK_INIT,
+    QCHECK
+};
+
+// Sort moves in descending order up to and including
+// a given limit. The order of moves smaller than the limit is left unspecified.
+void partial_insertion_sort(ExtMove* begin, ExtMove* end, int limit) {
 
     for (ExtMove *sortedEnd = begin, *p = begin + 1; p < end; ++p)
         if (p->value >= limit)
         {
             ExtMove tmp = *p, *q;
-            *p = *++sortedEnd;
+            *p          = *++sortedEnd;
             for (q = sortedEnd; q != begin && *(q - 1) < tmp; --q)
                 *q = *(q - 1);
             *q = tmp;
         }
-  }
-
-} // namespace
-
-
-/// Constructors of the MovePicker class. As arguments we pass information
-/// to help it to return the (presumably) good moves first, to decide which
-/// moves to return (in the quiescence search, for instance, we only want to
-/// search captures, promotions, and some checks) and how important good move
-/// ordering is at the current node.
-
-/// MovePicker constructor for the main search
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh,
-                                                             const CapturePieceToHistory* cph,
-                                                             const PieceToHistory** ch,
-                                                             Move cm,
-                                                             const Move* killers)
-           : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch),
-             ttMove(ttm), refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}}, depth(d)
-{
-  assert(d > 0);
-
-  stage = (pos.checkers() ? EVASION_TT : MAIN_TT) +
-          !(ttm && pos.pseudo_legal(ttm));
 }
 
-/// MovePicker constructor for quiescence search
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh,
-                                                             const CapturePieceToHistory* cph,
-                                                             const PieceToHistory** ch,
-                                                             Square rs)
-           : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch), ttMove(ttm), recaptureSquare(rs), depth(d)
-{
-  assert(d <= 0);
+}  // namespace
 
-  stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) +
-          !(   ttm
-            && pos.pseudo_legal(ttm));
+
+// Constructors of the MovePicker class. As arguments, we pass information
+// to help it return the (presumably) good moves first, to decide which
+// moves to return (in the quiescence search, for instance, we only want to
+// search captures, promotions, and some checks) and how important a good
+// move ordering is at the current node.
+
+// MovePicker constructor for the main search
+MovePicker::MovePicker(const Position&              p,
+                       Move                         ttm,
+                       Depth                        d,
+                       const ButterflyHistory*      mh,
+                       const CapturePieceToHistory* cph,
+                       const PieceToHistory**       ch,
+                       const PawnHistory*           ph,
+                       Move                         cm,
+                       const Move*                  killers) :
+    pos(p),
+    mainHistory(mh),
+    captureHistory(cph),
+    continuationHistory(ch),
+    pawnHistory(ph),
+    ttMove(ttm),
+    refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}},
+    depth(d) {
+    assert(d > 0);
+
+    stage = (pos.checkers() ? EVASION_TT : MAIN_TT) + !(ttm && pos.pseudo_legal(ttm));
 }
 
-/// MovePicker constructor for ProbCut: we generate captures with SEE greater
-/// than or equal to the given threshold.
-MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph)
-           : pos(p), captureHistory(cph), ttMove(ttm), threshold(th)
-{
-  assert(!pos.checkers());
+// Constructor for quiescence search
+MovePicker::MovePicker(const Position&              p,
+                       Move                         ttm,
+                       Depth                        d,
+                       const ButterflyHistory*      mh,
+                       const CapturePieceToHistory* cph,
+                       const PieceToHistory**       ch,
+                       const PawnHistory*           ph) :
+    pos(p),
+    mainHistory(mh),
+    captureHistory(cph),
+    continuationHistory(ch),
+    pawnHistory(ph),
+    ttMove(ttm),
+    depth(d) {
+    assert(d <= 0);
 
-  stage = PROBCUT_TT + !(ttm && pos.capture_stage(ttm)
-                             && pos.pseudo_legal(ttm)
-                             && pos.see_ge(ttm, threshold));
+    stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) + !(ttm && pos.pseudo_legal(ttm));
 }
 
-/// MovePicker::score() assigns a numerical value to each move in a list, used
-/// for sorting. Captures are ordered by Most Valuable Victim (MVV), preferring
-/// captures with a good history. Quiets moves are ordered using the history tables.
+// Constructor for ProbCut: we generate captures with SEE greater
+// than or equal to the given threshold.
+MovePicker::MovePicker(const Position& p, Move ttm, int th, const CapturePieceToHistory* cph) :
+    pos(p),
+    captureHistory(cph),
+    ttMove(ttm),
+    threshold(th) {
+    assert(!pos.checkers());
+
+    stage = PROBCUT_TT
+          + !(ttm && pos.capture_stage(ttm) && pos.pseudo_legal(ttm) && pos.see_ge(ttm, threshold));
+}
+
+// Assigns a numerical value to each move in a list, used
+// for sorting. Captures are ordered by Most Valuable Victim (MVV), preferring
+// captures with a good history. Quiets moves are ordered using the history tables.
 template<GenType Type>
 void MovePicker::score() {
 
-  static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
+    static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
 
-  [[maybe_unused]] Bitboard threatenedByPawn, threatenedByMinor, threatenedByRook, threatenedPieces;
-  if constexpr (Type == QUIETS)
-  {
-      Color us = pos.side_to_move();
+    [[maybe_unused]] Bitboard threatenedByPawn, threatenedByMinor, threatenedByRook,
+      threatenedPieces;
+    if constexpr (Type == QUIETS)
+    {
+        Color us = pos.side_to_move();
 
-      threatenedByPawn  = pos.attacks_by<PAWN>(~us);
-      threatenedByMinor = pos.attacks_by<KNIGHT>(~us) | pos.attacks_by<BISHOP>(~us) | threatenedByPawn;
-      threatenedByRook  = pos.attacks_by<ROOK>(~us) | threatenedByMinor;
+        threatenedByPawn = pos.attacks_by<PAWN>(~us);
+        threatenedByMinor =
+          pos.attacks_by<KNIGHT>(~us) | pos.attacks_by<BISHOP>(~us) | threatenedByPawn;
+        threatenedByRook = pos.attacks_by<ROOK>(~us) | threatenedByMinor;
 
-      // Pieces threatened by pieces of lesser material value
-      threatenedPieces = (pos.pieces(us, QUEEN) & threatenedByRook)
-                       | (pos.pieces(us, ROOK)  & threatenedByMinor)
-                       | (pos.pieces(us, KNIGHT, BISHOP) & threatenedByPawn);
-  }
+        // Pieces threatened by pieces of lesser material value
+        threatenedPieces = (pos.pieces(us, QUEEN) & threatenedByRook)
+                         | (pos.pieces(us, ROOK) & threatenedByMinor)
+                         | (pos.pieces(us, KNIGHT, BISHOP) & threatenedByPawn);
+    }
 
-  for (auto& m : *this)
-      if constexpr (Type == CAPTURES)
-          m.value =  (7 * int(PieceValue[MG][pos.piece_on(to_sq(m))])
-                   +     (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))]) / 16;
+    for (auto& m : *this)
+        if constexpr (Type == CAPTURES)
+            m.value =
+              7 * int(PieceValue[pos.piece_on(m.to_sq())])
+              + (*captureHistory)[pos.moved_piece(m)][m.to_sq()][type_of(pos.piece_on(m.to_sq()))];
 
-      else if constexpr (Type == QUIETS)
-          m.value =  2 * (*mainHistory)[pos.side_to_move()][from_to(m)]
-                   + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
-                   +     (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
-                   +     (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
-                   +     (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)]
-                   +     (threatenedPieces & from_sq(m) ?
-                           (type_of(pos.moved_piece(m)) == QUEEN && !(to_sq(m) & threatenedByRook)  ? 50000
-                          : type_of(pos.moved_piece(m)) == ROOK  && !(to_sq(m) & threatenedByMinor) ? 25000
-                          :                                         !(to_sq(m) & threatenedByPawn)  ? 15000
-                          :                                                                           0)
-                          :                                                                           0)
-                   +     bool(pos.check_squares(type_of(pos.moved_piece(m))) & to_sq(m)) * 16384;
-      else // Type == EVASIONS
-      {
-          if (pos.capture_stage(m))
-              m.value =  PieceValue[MG][pos.piece_on(to_sq(m))]
-                       - Value(type_of(pos.moved_piece(m)))
-                       + (1 << 28);
-          else
-              m.value =  (*mainHistory)[pos.side_to_move()][from_to(m)]
-                       + (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)];
-      }
+        else if constexpr (Type == QUIETS)
+        {
+            Piece     pc   = pos.moved_piece(m);
+            PieceType pt   = type_of(pc);
+            Square    from = m.from_sq();
+            Square    to   = m.to_sq();
+
+            // histories
+            m.value = 2 * (*mainHistory)[pos.side_to_move()][m.from_to()];
+            m.value += 2 * (*pawnHistory)[pawn_structure_index(pos)][pc][to];
+            m.value += 2 * (*continuationHistory[0])[pc][to];
+            m.value += (*continuationHistory[1])[pc][to];
+            m.value += (*continuationHistory[2])[pc][to] / 4;
+            m.value += (*continuationHistory[3])[pc][to];
+            m.value += (*continuationHistory[5])[pc][to];
+
+            // bonus for checks
+            m.value += bool(pos.check_squares(pt) & to) * 16384;
+
+            // bonus for escaping from capture
+            m.value += threatenedPieces & from ? (pt == QUEEN && !(to & threatenedByRook)   ? 50000
+                                                  : pt == ROOK && !(to & threatenedByMinor) ? 25000
+                                                  : !(to & threatenedByPawn)                ? 15000
+                                                                                            : 0)
+                                               : 0;
+
+            // malus for putting piece en prise
+            m.value -= !(threatenedPieces & from)
+                       ? (pt == QUEEN ? bool(to & threatenedByRook) * 50000
+                                          + bool(to & threatenedByMinor) * 10000
+                          : pt == ROOK ? bool(to & threatenedByMinor) * 25000
+                          : pt != PAWN ? bool(to & threatenedByPawn) * 15000
+                                       : 0)
+                       : 0;
+        }
+
+        else  // Type == EVASIONS
+        {
+            if (pos.capture_stage(m))
+                m.value =
+                  PieceValue[pos.piece_on(m.to_sq())] - type_of(pos.moved_piece(m)) + (1 << 28);
+            else
+                m.value = (*mainHistory)[pos.side_to_move()][m.from_to()]
+                        + (*continuationHistory[0])[pos.moved_piece(m)][m.to_sq()]
+                        + (*pawnHistory)[pawn_structure_index(pos)][pos.moved_piece(m)][m.to_sq()];
+        }
 }
 
-/// MovePicker::select() returns the next move satisfying a predicate function.
-/// It never returns the TT move.
+// Returns the next move satisfying a predicate function.
+// It never returns the TT move.
 template<MovePicker::PickType T, typename Pred>
 Move MovePicker::select(Pred filter) {
 
-  while (cur < endMoves)
-  {
-      if constexpr (T == Best)
-          std::swap(*cur, *std::max_element(cur, endMoves));
+    while (cur < endMoves)
+    {
+        if constexpr (T == Best)
+            std::swap(*cur, *std::max_element(cur, endMoves));
 
-      if (*cur != ttMove && filter())
-          return *cur++;
+        if (*cur != ttMove && filter())
+            return *cur++;
 
-      cur++;
-  }
-  return MOVE_NONE;
+        cur++;
+    }
+    return Move::none();
 }
 
-/// MovePicker::next_move() is the most important method of the MovePicker class. It
-/// returns a new pseudo-legal move every time it is called until there are no more
-/// moves left, picking the move with the highest score from a list of generated moves.
+// Most important method of the MovePicker class. It
+// returns a new pseudo-legal move every time it is called until there are no more
+// moves left, picking the move with the highest score from a list of generated moves.
 Move MovePicker::next_move(bool skipQuiets) {
 
+    auto quiet_threshold = [](Depth d) { return -3330 * d; };
+
 top:
-  switch (stage) {
+    switch (stage)
+    {
 
-  case MAIN_TT:
-  case EVASION_TT:
-  case QSEARCH_TT:
-  case PROBCUT_TT:
-      ++stage;
-      return ttMove;
+    case MAIN_TT :
+    case EVASION_TT :
+    case QSEARCH_TT :
+    case PROBCUT_TT :
+        ++stage;
+        return ttMove;
 
-  case CAPTURE_INIT:
-  case PROBCUT_INIT:
-  case QCAPTURE_INIT:
-      cur = endBadCaptures = moves;
-      endMoves = generate<CAPTURES>(pos, cur);
+    case CAPTURE_INIT :
+    case PROBCUT_INIT :
+    case QCAPTURE_INIT :
+        cur = endBadCaptures = moves;
+        endMoves             = generate<CAPTURES>(pos, cur);
 
-      score<CAPTURES>();
-      partial_insertion_sort(cur, endMoves, std::numeric_limits<int>::min());
-      ++stage;
-      goto top;
+        score<CAPTURES>();
+        partial_insertion_sort(cur, endMoves, std::numeric_limits<int>::min());
+        ++stage;
+        goto top;
 
-  case GOOD_CAPTURE:
-      if (select<Next>([&](){
-                       return pos.see_ge(*cur, Value(-cur->value)) ?
-                              // Move losing capture to endBadCaptures to be tried later
-                              true : (*endBadCaptures++ = *cur, false); }))
-          return *(cur - 1);
+    case GOOD_CAPTURE :
+        if (select<Next>([&]() {
+                // Move losing capture to endBadCaptures to be tried later
+                return pos.see_ge(*cur, -cur->value / 18) ? true
+                                                          : (*endBadCaptures++ = *cur, false);
+            }))
+            return *(cur - 1);
 
-      // Prepare the pointers to loop over the refutations array
-      cur = std::begin(refutations);
-      endMoves = std::end(refutations);
+        // Prepare the pointers to loop over the refutations array
+        cur      = std::begin(refutations);
+        endMoves = std::end(refutations);
 
-      // If the countermove is the same as a killer, skip it
-      if (   refutations[0].move == refutations[2].move
-          || refutations[1].move == refutations[2].move)
-          --endMoves;
+        // If the countermove is the same as a killer, skip it
+        if (refutations[0] == refutations[2] || refutations[1] == refutations[2])
+            --endMoves;
 
-      ++stage;
-      [[fallthrough]];
+        ++stage;
+        [[fallthrough]];
 
-  case REFUTATION:
-      if (select<Next>([&](){ return    *cur != MOVE_NONE
-                                    && !pos.capture_stage(*cur)
-                                    &&  pos.pseudo_legal(*cur); }))
-          return *(cur - 1);
-      ++stage;
-      [[fallthrough]];
+    case REFUTATION :
+        if (select<Next>([&]() {
+                return *cur != Move::none() && !pos.capture_stage(*cur) && pos.pseudo_legal(*cur);
+            }))
+            return *(cur - 1);
+        ++stage;
+        [[fallthrough]];
 
-  case QUIET_INIT:
-      if (!skipQuiets)
-      {
-          cur = endBadCaptures;
-          endMoves = generate<QUIETS>(pos, cur);
+    case QUIET_INIT :
+        if (!skipQuiets)
+        {
+            cur      = endBadCaptures;
+            endMoves = beginBadQuiets = endBadQuiets = generate<QUIETS>(pos, cur);
 
-          score<QUIETS>();
-          partial_insertion_sort(cur, endMoves, -3000 * depth);
-      }
+            score<QUIETS>();
+            partial_insertion_sort(cur, endMoves, quiet_threshold(depth));
+        }
 
-      ++stage;
-      [[fallthrough]];
+        ++stage;
+        [[fallthrough]];
 
-  case QUIET:
-      if (   !skipQuiets
-          && select<Next>([&](){return   *cur != refutations[0].move
-                                      && *cur != refutations[1].move
-                                      && *cur != refutations[2].move;}))
-          return *(cur - 1);
+    case GOOD_QUIET :
+        if (!skipQuiets && select<Next>([&]() {
+                return *cur != refutations[0] && *cur != refutations[1] && *cur != refutations[2];
+            }))
+        {
+            if ((cur - 1)->value > -8000 || (cur - 1)->value <= quiet_threshold(depth))
+                return *(cur - 1);
 
-      // Prepare the pointers to loop over the bad captures
-      cur = moves;
-      endMoves = endBadCaptures;
+            // Remaining quiets are bad
+            beginBadQuiets = cur - 1;
+        }
 
-      ++stage;
-      [[fallthrough]];
+        // Prepare the pointers to loop over the bad captures
+        cur      = moves;
+        endMoves = endBadCaptures;
 
-  case BAD_CAPTURE:
-      return select<Next>([](){ return true; });
+        ++stage;
+        [[fallthrough]];
 
-  case EVASION_INIT:
-      cur = moves;
-      endMoves = generate<EVASIONS>(pos, cur);
+    case BAD_CAPTURE :
+        if (select<Next>([]() { return true; }))
+            return *(cur - 1);
 
-      score<EVASIONS>();
-      ++stage;
-      [[fallthrough]];
+        // Prepare the pointers to loop over the bad quiets
+        cur      = beginBadQuiets;
+        endMoves = endBadQuiets;
 
-  case EVASION:
-      return select<Best>([](){ return true; });
+        ++stage;
+        [[fallthrough]];
 
-  case PROBCUT:
-      return select<Next>([&](){ return pos.see_ge(*cur, threshold); });
+    case BAD_QUIET :
+        if (!skipQuiets)
+            return select<Next>([&]() {
+                return *cur != refutations[0] && *cur != refutations[1] && *cur != refutations[2];
+            });
 
-  case QCAPTURE:
-      if (select<Next>([&](){ return   depth > DEPTH_QS_RECAPTURES
-                                    || to_sq(*cur) == recaptureSquare; }))
-          return *(cur - 1);
+        return Move::none();
 
-      // If we did not find any move and we do not try checks, we have finished
-      if (depth != DEPTH_QS_CHECKS)
-          return MOVE_NONE;
+    case EVASION_INIT :
+        cur      = moves;
+        endMoves = generate<EVASIONS>(pos, cur);
 
-      ++stage;
-      [[fallthrough]];
+        score<EVASIONS>();
+        ++stage;
+        [[fallthrough]];
 
-  case QCHECK_INIT:
-      cur = moves;
-      endMoves = generate<QUIET_CHECKS>(pos, cur);
+    case EVASION :
+        return select<Best>([]() { return true; });
 
-      ++stage;
-      [[fallthrough]];
+    case PROBCUT :
+        return select<Next>([&]() { return pos.see_ge(*cur, threshold); });
 
-  case QCHECK:
-      return select<Next>([](){ return true; });
-  }
+    case QCAPTURE :
+        if (select<Next>([]() { return true; }))
+            return *(cur - 1);
 
-  assert(false);
-  return MOVE_NONE; // Silence warning
+        // If we did not find any move and we do not try checks, we have finished
+        if (depth != DEPTH_QS_CHECKS)
+            return Move::none();
+
+        ++stage;
+        [[fallthrough]];
+
+    case QCHECK_INIT :
+        cur      = moves;
+        endMoves = generate<QUIET_CHECKS>(pos, cur);
+
+        ++stage;
+        [[fallthrough]];
+
+    case QCHECK :
+        return select<Next>([]() { return true; });
+    }
+
+    assert(false);
+    return Move::none();  // Silence warning
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/movepick.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,136 +20,181 @@
 #define MOVEPICK_H_INCLUDED
 
 #include <array>
+#include <cassert>
+#include <cmath>
+#include <cstdint>
+#include <cstdlib>
 #include <limits>
-#include <type_traits>
+#include <type_traits>  // IWYU pragma: keep
 
 #include "movegen.h"
-#include "position.h"
 #include "types.h"
+#include "position.h"
 
 namespace Stockfish {
 
-/// StatsEntry stores the stat table value. It is usually a number but could
-/// be a move or even a nested history. We use a class instead of naked value
-/// to directly call history update operator<<() on the entry so to use stats
-/// tables at caller sites as simple multi-dim arrays.
+constexpr int PAWN_HISTORY_SIZE        = 512;    // has to be a power of 2
+constexpr int CORRECTION_HISTORY_SIZE  = 16384;  // has to be a power of 2
+constexpr int CORRECTION_HISTORY_LIMIT = 1024;
+
+static_assert((PAWN_HISTORY_SIZE & (PAWN_HISTORY_SIZE - 1)) == 0,
+              "PAWN_HISTORY_SIZE has to be a power of 2");
+
+static_assert((CORRECTION_HISTORY_SIZE & (CORRECTION_HISTORY_SIZE - 1)) == 0,
+              "CORRECTION_HISTORY_SIZE has to be a power of 2");
+
+enum PawnHistoryType {
+    Normal,
+    Correction
+};
+
+template<PawnHistoryType T = Normal>
+inline int pawn_structure_index(const Position& pos) {
+    return pos.pawn_key() & ((T == Normal ? PAWN_HISTORY_SIZE : CORRECTION_HISTORY_SIZE) - 1);
+}
+
+// StatsEntry stores the stat table value. It is usually a number but could
+// be a move or even a nested history. We use a class instead of a naked value
+// to directly call history update operator<<() on the entry so to use stats
+// tables at caller sites as simple multi-dim arrays.
 template<typename T, int D>
 class StatsEntry {
 
-  T entry;
+    T entry;
 
-public:
-  void operator=(const T& v) { entry = v; }
-  T* operator&() { return &entry; }
-  T* operator->() { return &entry; }
-  operator const T&() const { return entry; }
+   public:
+    void operator=(const T& v) { entry = v; }
+    T*   operator&() { return &entry; }
+    T*   operator->() { return &entry; }
+    operator const T&() const { return entry; }
 
-  void operator<<(int bonus) {
-    assert(abs(bonus) <= D); // Ensure range is [-D, D]
-    static_assert(D <= std::numeric_limits<T>::max(), "D overflows T");
+    void operator<<(int bonus) {
+        assert(std::abs(bonus) <= D);  // Ensure range is [-D, D]
+        static_assert(D <= std::numeric_limits<T>::max(), "D overflows T");
 
-    entry += bonus - entry * abs(bonus) / D;
+        entry += bonus - entry * std::abs(bonus) / D;
 
-    assert(abs(entry) <= D);
-  }
+        assert(std::abs(entry) <= D);
+    }
 };
 
-/// Stats is a generic N-dimensional array used to store various statistics.
-/// The first template parameter T is the base type of the array, the second
-/// template parameter D limits the range of updates in [-D, D] when we update
-/// values with the << operator, while the last parameters (Size and Sizes)
-/// encode the dimensions of the array.
-template <typename T, int D, int Size, int... Sizes>
-struct Stats : public std::array<Stats<T, D, Sizes...>, Size>
-{
-  using stats = Stats<T, D, Size, Sizes...>;
+// Stats is a generic N-dimensional array used to store various statistics.
+// The first template parameter T is the base type of the array, and the second
+// template parameter D limits the range of updates in [-D, D] when we update
+// values with the << operator, while the last parameters (Size and Sizes)
+// encode the dimensions of the array.
+template<typename T, int D, int Size, int... Sizes>
+struct Stats: public std::array<Stats<T, D, Sizes...>, Size> {
+    using stats = Stats<T, D, Size, Sizes...>;
 
-  void fill(const T& v) {
+    void fill(const T& v) {
 
-    // For standard-layout 'this' points to first struct member
-    assert(std::is_standard_layout<stats>::value);
+        // For standard-layout 'this' points to the first struct member
+        assert(std::is_standard_layout_v<stats>);
 
-    using entry = StatsEntry<T, D>;
-    entry* p = reinterpret_cast<entry*>(this);
-    std::fill(p, p + sizeof(*this) / sizeof(entry), v);
-  }
+        using entry = StatsEntry<T, D>;
+        entry* p    = reinterpret_cast<entry*>(this);
+        std::fill(p, p + sizeof(*this) / sizeof(entry), v);
+    }
 };
 
-template <typename T, int D, int Size>
-struct Stats<T, D, Size> : public std::array<StatsEntry<T, D>, Size> {};
+template<typename T, int D, int Size>
+struct Stats<T, D, Size>: public std::array<StatsEntry<T, D>, Size> {};
 
-/// In stats table, D=0 means that the template parameter is not used
-enum StatsParams { NOT_USED = 0 };
-enum StatsType { NoCaptures, Captures };
+// In stats table, D=0 means that the template parameter is not used
+enum StatsParams {
+    NOT_USED = 0
+};
+enum StatsType {
+    NoCaptures,
+    Captures
+};
 
-/// ButterflyHistory records how often quiet moves have been successful or
-/// unsuccessful during the current search, and is used for reduction and move
-/// ordering decisions. It uses 2 tables (one for each color) indexed by
-/// the move's from and to squares, see www.chessprogramming.org/Butterfly_Boards
-/// (~11 elo)
+// ButterflyHistory records how often quiet moves have been successful or unsuccessful
+// during the current search, and is used for reduction and move ordering decisions.
+// It uses 2 tables (one for each color) indexed by the move's from and to squares,
+// see www.chessprogramming.org/Butterfly_Boards (~11 elo)
 using ButterflyHistory = Stats<int16_t, 7183, COLOR_NB, int(SQUARE_NB) * int(SQUARE_NB)>;
 
-/// CounterMoveHistory stores counter moves indexed by [piece][to] of the previous
-/// move, see www.chessprogramming.org/Countermove_Heuristic
+// CounterMoveHistory stores counter moves indexed by [piece][to] of the previous
+// move, see www.chessprogramming.org/Countermove_Heuristic
 using CounterMoveHistory = Stats<Move, NOT_USED, PIECE_NB, SQUARE_NB>;
 
-/// CapturePieceToHistory is addressed by a move's [piece][to][captured piece type]
+// CapturePieceToHistory is addressed by a move's [piece][to][captured piece type]
 using CapturePieceToHistory = Stats<int16_t, 10692, PIECE_NB, SQUARE_NB, PIECE_TYPE_NB>;
 
-/// PieceToHistory is like ButterflyHistory but is addressed by a move's [piece][to]
+// PieceToHistory is like ButterflyHistory but is addressed by a move's [piece][to]
 using PieceToHistory = Stats<int16_t, 29952, PIECE_NB, SQUARE_NB>;
 
-/// ContinuationHistory is the combined history of a given pair of moves, usually
-/// the current one given a previous one. The nested history table is based on
-/// PieceToHistory instead of ButterflyBoards.
-/// (~63 elo)
+// ContinuationHistory is the combined history of a given pair of moves, usually
+// the current one given a previous one. The nested history table is based on
+// PieceToHistory instead of ButterflyBoards.
+// (~63 elo)
 using ContinuationHistory = Stats<PieceToHistory, NOT_USED, PIECE_NB, SQUARE_NB>;
 
+// PawnHistory is addressed by the pawn structure and a move's [piece][to]
+using PawnHistory = Stats<int16_t, 8192, PAWN_HISTORY_SIZE, PIECE_NB, SQUARE_NB>;
 
-/// MovePicker class is used to pick one pseudo-legal move at a time from the
-/// current position. The most important method is next_move(), which returns a
-/// new pseudo-legal move each time it is called, until there are no moves left,
-/// when MOVE_NONE is returned. In order to improve the efficiency of the
-/// alpha-beta algorithm, MovePicker attempts to return the moves which are most
-/// likely to get a cut-off first.
+// CorrectionHistory is addressed by color and pawn structure
+using CorrectionHistory =
+  Stats<int16_t, CORRECTION_HISTORY_LIMIT, COLOR_NB, CORRECTION_HISTORY_SIZE>;
+
+// MovePicker class is used to pick one pseudo-legal move at a time from the
+// current position. The most important method is next_move(), which returns a
+// new pseudo-legal move each time it is called, until there are no moves left,
+// when Move::none() is returned. In order to improve the efficiency of the
+// alpha-beta algorithm, MovePicker attempts to return the moves which are most
+// likely to get a cut-off first.
 class MovePicker {
 
-  enum PickType { Next, Best };
+    enum PickType {
+        Next,
+        Best
+    };
 
-public:
-  MovePicker(const MovePicker&) = delete;
-  MovePicker& operator=(const MovePicker&) = delete;
-  MovePicker(const Position&, Move, Depth, const ButterflyHistory*,
-                                           const CapturePieceToHistory*,
-                                           const PieceToHistory**,
-                                           Move,
-                                           const Move*);
-  MovePicker(const Position&, Move, Depth, const ButterflyHistory*,
-                                           const CapturePieceToHistory*,
-                                           const PieceToHistory**,
-                                           Square);
-  MovePicker(const Position&, Move, Value, const CapturePieceToHistory*);
-  Move next_move(bool skipQuiets = false);
+   public:
+    MovePicker(const MovePicker&)            = delete;
+    MovePicker& operator=(const MovePicker&) = delete;
+    MovePicker(const Position&,
+               Move,
+               Depth,
+               const ButterflyHistory*,
+               const CapturePieceToHistory*,
+               const PieceToHistory**,
+               const PawnHistory*,
+               Move,
+               const Move*);
+    MovePicker(const Position&,
+               Move,
+               Depth,
+               const ButterflyHistory*,
+               const CapturePieceToHistory*,
+               const PieceToHistory**,
+               const PawnHistory*);
+    MovePicker(const Position&, Move, int, const CapturePieceToHistory*);
+    Move next_move(bool skipQuiets = false);
 
-private:
-  template<PickType T, typename Pred> Move select(Pred);
-  template<GenType> void score();
-  ExtMove* begin() { return cur; }
-  ExtMove* end() { return endMoves; }
+   private:
+    template<PickType T, typename Pred>
+    Move select(Pred);
+    template<GenType>
+    void     score();
+    ExtMove* begin() { return cur; }
+    ExtMove* end() { return endMoves; }
 
-  const Position& pos;
-  const ButterflyHistory* mainHistory;
-  const CapturePieceToHistory* captureHistory;
-  const PieceToHistory** continuationHistory;
-  Move ttMove;
-  ExtMove refutations[3], *cur, *endMoves, *endBadCaptures;
-  int stage;
-  Square recaptureSquare;
-  Value threshold;
-  Depth depth;
-  ExtMove moves[MAX_MOVES];
+    const Position&              pos;
+    const ButterflyHistory*      mainHistory;
+    const CapturePieceToHistory* captureHistory;
+    const PieceToHistory**       continuationHistory;
+    const PawnHistory*           pawnHistory;
+    Move                         ttMove;
+    ExtMove refutations[3], *cur, *endMoves, *endBadCaptures, *beginBadQuiets, *endBadQuiets;
+    int     stage;
+    int     threshold;
+    Depth   depth;
+    ExtMove moves[MAX_MOVES];
 };
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#endif // #ifndef MOVEPICK_H_INCLUDED
+#endif  // #ifndef MOVEPICK_H_INCLUDED

src/nnue/evaluate_nnue.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,312 +18,375 @@
 
 // Code for calculating NNUE evaluation function
 
+#include "evaluate_nnue.h"
+
+#include <cmath>
+#include <cstdlib>
+#include <cstring>
 #include <fstream>
 #include <iomanip>
 #include <iostream>
-#include <set>
+#include <optional>
 #include <sstream>
 #include <string_view>
+#include <type_traits>
+#include <unordered_map>
 
 #include "../evaluate.h"
+#include "../misc.h"
 #include "../position.h"
-#include "../uci.h"
 #include "../types.h"
-
-#include "evaluate_nnue.h"
+#include "../uci.h"
+#include "nnue_accumulator.h"
+#include "nnue_common.h"
 
 namespace Stockfish::Eval::NNUE {
 
-  // Input feature converter
-  LargePagePtr<FeatureTransformer> featureTransformer;
+// Input feature converter
+LargePagePtr<FeatureTransformer<TransformedFeatureDimensionsBig, &StateInfo::accumulatorBig>>
+  featureTransformerBig;
+LargePagePtr<FeatureTransformer<TransformedFeatureDimensionsSmall, &StateInfo::accumulatorSmall>>
+  featureTransformerSmall;
 
-  // Evaluation function
-  AlignedPtr<Network> network[LayerStacks];
+// Evaluation function
+AlignedPtr<Network<TransformedFeatureDimensionsBig, L2Big, L3Big>>       networkBig[LayerStacks];
+AlignedPtr<Network<TransformedFeatureDimensionsSmall, L2Small, L3Small>> networkSmall[LayerStacks];
 
-  // Evaluation function file name
-  std::string fileName;
-  std::string netDescription;
+// Evaluation function file names
 
-  namespace Detail {
+namespace Detail {
 
-  // Initialize the evaluation function parameters
-  template <typename T>
-  void initialize(AlignedPtr<T>& pointer) {
+// Initialize the evaluation function parameters
+template<typename T>
+void initialize(AlignedPtr<T>& pointer) {
 
     pointer.reset(reinterpret_cast<T*>(std_aligned_alloc(alignof(T), sizeof(T))));
     std::memset(pointer.get(), 0, sizeof(T));
-  }
+}
 
-  template <typename T>
-  void initialize(LargePagePtr<T>& pointer) {
+template<typename T>
+void initialize(LargePagePtr<T>& pointer) {
 
-    static_assert(alignof(T) <= 4096, "aligned_large_pages_alloc() may fail for such a big alignment requirement of T");
+    static_assert(alignof(T) <= 4096,
+                  "aligned_large_pages_alloc() may fail for such a big alignment requirement of T");
     pointer.reset(reinterpret_cast<T*>(aligned_large_pages_alloc(sizeof(T))));
     std::memset(pointer.get(), 0, sizeof(T));
-  }
+}
 
-  // Read evaluation function parameters
-  template <typename T>
-  bool read_parameters(std::istream& stream, T& reference) {
+// Read evaluation function parameters
+template<typename T>
+bool read_parameters(std::istream& stream, T& reference) {
 
     std::uint32_t header;
     header = read_little_endian<std::uint32_t>(stream);
-    if (!stream || header != T::get_hash_value()) return false;
+    if (!stream || header != T::get_hash_value())
+        return false;
     return reference.read_parameters(stream);
-  }
+}
 
-  // Write evaluation function parameters
-  template <typename T>
-  bool write_parameters(std::ostream& stream, const T& reference) {
+// Write evaluation function parameters
+template<typename T>
+bool write_parameters(std::ostream& stream, const T& reference) {
 
     write_little_endian<std::uint32_t>(stream, T::get_hash_value());
     return reference.write_parameters(stream);
-  }
+}
 
-  }  // namespace Detail
+}  // namespace Detail
 
-  // Initialize the evaluation function parameters
-  static void initialize() {
 
-    Detail::initialize(featureTransformer);
-    for (std::size_t i = 0; i < LayerStacks; ++i)
-      Detail::initialize(network[i]);
-  }
+// Initialize the evaluation function parameters
+static void initialize(NetSize netSize) {
 
-  // Read network header
-  static bool read_header(std::istream& stream, std::uint32_t* hashValue, std::string* desc)
-  {
+    if (netSize == Small)
+    {
+        Detail::initialize(featureTransformerSmall);
+        for (std::size_t i = 0; i < LayerStacks; ++i)
+            Detail::initialize(networkSmall[i]);
+    }
+    else
+    {
+        Detail::initialize(featureTransformerBig);
+        for (std::size_t i = 0; i < LayerStacks; ++i)
+            Detail::initialize(networkBig[i]);
+    }
+}
+
+// Read network header
+static bool read_header(std::istream& stream, std::uint32_t* hashValue, std::string* desc) {
     std::uint32_t version, size;
 
-    version     = read_little_endian<std::uint32_t>(stream);
-    *hashValue  = read_little_endian<std::uint32_t>(stream);
-    size        = read_little_endian<std::uint32_t>(stream);
-    if (!stream || version != Version) return false;
+    version    = read_little_endian<std::uint32_t>(stream);
+    *hashValue = read_little_endian<std::uint32_t>(stream);
+    size       = read_little_endian<std::uint32_t>(stream);
+    if (!stream || version != Version)
+        return false;
     desc->resize(size);
     stream.read(&(*desc)[0], size);
     return !stream.fail();
-  }
+}
 
-  // Write network header
-  static bool write_header(std::ostream& stream, std::uint32_t hashValue, const std::string& desc)
-  {
+// Write network header
+static bool write_header(std::ostream& stream, std::uint32_t hashValue, const std::string& desc) {
     write_little_endian<std::uint32_t>(stream, Version);
     write_little_endian<std::uint32_t>(stream, hashValue);
-    write_little_endian<std::uint32_t>(stream, (std::uint32_t)desc.size());
+    write_little_endian<std::uint32_t>(stream, std::uint32_t(desc.size()));
     stream.write(&desc[0], desc.size());
     return !stream.fail();
-  }
+}
 
-  // Read network parameters
-  static bool read_parameters(std::istream& stream) {
+// Read network parameters
+static bool read_parameters(std::istream& stream, NetSize netSize, std::string& netDescription) {
 
     std::uint32_t hashValue;
-    if (!read_header(stream, &hashValue, &netDescription)) return false;
-    if (hashValue != HashValue) return false;
-    if (!Detail::read_parameters(stream, *featureTransformer)) return false;
+    if (!read_header(stream, &hashValue, &netDescription))
+        return false;
+    if (hashValue != HashValue[netSize])
+        return false;
+    if (netSize == Big && !Detail::read_parameters(stream, *featureTransformerBig))
+        return false;
+    if (netSize == Small && !Detail::read_parameters(stream, *featureTransformerSmall))
+        return false;
     for (std::size_t i = 0; i < LayerStacks; ++i)
-      if (!Detail::read_parameters(stream, *(network[i]))) return false;
+    {
+        if (netSize == Big && !Detail::read_parameters(stream, *(networkBig[i])))
+            return false;
+        if (netSize == Small && !Detail::read_parameters(stream, *(networkSmall[i])))
+            return false;
+    }
     return stream && stream.peek() == std::ios::traits_type::eof();
-  }
+}
 
-  // Write network parameters
-  static bool write_parameters(std::ostream& stream) {
+// Write network parameters
+static bool
+write_parameters(std::ostream& stream, NetSize netSize, const std::string& netDescription) {
 
-    if (!write_header(stream, HashValue, netDescription)) return false;
-    if (!Detail::write_parameters(stream, *featureTransformer)) return false;
+    if (!write_header(stream, HashValue[netSize], netDescription))
+        return false;
+    if (netSize == Big && !Detail::write_parameters(stream, *featureTransformerBig))
+        return false;
+    if (netSize == Small && !Detail::write_parameters(stream, *featureTransformerSmall))
+        return false;
     for (std::size_t i = 0; i < LayerStacks; ++i)
-      if (!Detail::write_parameters(stream, *(network[i]))) return false;
-    return (bool)stream;
-  }
+    {
+        if (netSize == Big && !Detail::write_parameters(stream, *(networkBig[i])))
+            return false;
+        if (netSize == Small && !Detail::write_parameters(stream, *(networkSmall[i])))
+            return false;
+    }
+    return bool(stream);
+}
 
-  void hint_common_parent_position(const Position& pos) {
-    if (Eval::useNNUE)
-        featureTransformer->hint_common_access(pos);
-  }
+void hint_common_parent_position(const Position& pos) {
 
-  // Evaluation function. Perform differential calculation.
-  Value evaluate(const Position& pos, bool adjusted, int* complexity) {
+    int simpleEval = simple_eval(pos, pos.side_to_move());
+    if (std::abs(simpleEval) > 1050)
+        featureTransformerSmall->hint_common_access(pos);
+    else
+        featureTransformerBig->hint_common_access(pos);
+}
+
+// Evaluation function. Perform differential calculation.
+template<NetSize Net_Size>
+Value evaluate(const Position& pos, bool adjusted, int* complexity) {
 
     // We manually align the arrays on the stack because with gcc < 9.3
     // overaligning stack variables with alignas() doesn't work correctly.
 
     constexpr uint64_t alignment = CacheLineSize;
-    constexpr int delta = 24;
+    constexpr int      delta     = 24;
 
 #if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
-    TransformedFeatureType transformedFeaturesUnaligned[
-      FeatureTransformer::BufferSize + alignment / sizeof(TransformedFeatureType)];
+    TransformedFeatureType transformedFeaturesUnaligned
+      [FeatureTransformer < Net_Size == Small ? TransformedFeatureDimensionsSmall
+                                              : TransformedFeatureDimensionsBig,
+       nullptr > ::BufferSize + alignment / sizeof(TransformedFeatureType)];
 
     auto* transformedFeatures = align_ptr_up<alignment>(&transformedFeaturesUnaligned[0]);
 #else
-    alignas(alignment)
-      TransformedFeatureType transformedFeatures[FeatureTransformer::BufferSize];
+
+    alignas(alignment) TransformedFeatureType
+      transformedFeatures[FeatureTransformer < Net_Size == Small ? TransformedFeatureDimensionsSmall
+                                                                 : TransformedFeatureDimensionsBig,
+                          nullptr > ::BufferSize];
 #endif
 
     ASSERT_ALIGNED(transformedFeatures, alignment);
 
-    const int bucket = (pos.count<ALL_PIECES>() - 1) / 4;
-    const auto psqt = featureTransformer->transform(pos, transformedFeatures, bucket);
-    const auto positional = network[bucket]->propagate(transformedFeatures);
+    const int  bucket     = (pos.count<ALL_PIECES>() - 1) / 4;
+    const auto psqt       = Net_Size == Small
+                            ? featureTransformerSmall->transform(pos, transformedFeatures, bucket)
+                            : featureTransformerBig->transform(pos, transformedFeatures, bucket);
+    const auto positional = Net_Size == Small ? networkSmall[bucket]->propagate(transformedFeatures)
+                                              : networkBig[bucket]->propagate(transformedFeatures);
 
     if (complexity)
-        *complexity = abs(psqt - positional) / OutputScale;
+        *complexity = std::abs(psqt - positional) / OutputScale;
 
     // Give more value to positional evaluation when adjusted flag is set
     if (adjusted)
-        return static_cast<Value>(((1024 - delta) * psqt + (1024 + delta) * positional) / (1024 * OutputScale));
+        return static_cast<Value>(((1024 - delta) * psqt + (1024 + delta) * positional)
+                                  / (1024 * OutputScale));
     else
         return static_cast<Value>((psqt + positional) / OutputScale);
-  }
+}
 
-  struct NnueEvalTrace {
+template Value evaluate<Big>(const Position& pos, bool adjusted, int* complexity);
+template Value evaluate<Small>(const Position& pos, bool adjusted, int* complexity);
+
+struct NnueEvalTrace {
     static_assert(LayerStacks == PSQTBuckets);
 
-    Value psqt[LayerStacks];
-    Value positional[LayerStacks];
+    Value       psqt[LayerStacks];
+    Value       positional[LayerStacks];
     std::size_t correctBucket;
-  };
+};
 
-  static NnueEvalTrace trace_evaluate(const Position& pos) {
+static NnueEvalTrace trace_evaluate(const Position& pos) {
 
     // We manually align the arrays on the stack because with gcc < 9.3
     // overaligning stack variables with alignas() doesn't work correctly.
-
     constexpr uint64_t alignment = CacheLineSize;
 
 #if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
-    TransformedFeatureType transformedFeaturesUnaligned[
-      FeatureTransformer::BufferSize + alignment / sizeof(TransformedFeatureType)];
+    TransformedFeatureType transformedFeaturesUnaligned
+      [FeatureTransformer<TransformedFeatureDimensionsBig, nullptr>::BufferSize
+       + alignment / sizeof(TransformedFeatureType)];
 
     auto* transformedFeatures = align_ptr_up<alignment>(&transformedFeaturesUnaligned[0]);
 #else
-    alignas(alignment)
-      TransformedFeatureType transformedFeatures[FeatureTransformer::BufferSize];
+    alignas(alignment) TransformedFeatureType
+      transformedFeatures[FeatureTransformer<TransformedFeatureDimensionsBig, nullptr>::BufferSize];
 #endif
 
     ASSERT_ALIGNED(transformedFeatures, alignment);
 
     NnueEvalTrace t{};
     t.correctBucket = (pos.count<ALL_PIECES>() - 1) / 4;
-    for (IndexType bucket = 0; bucket < LayerStacks; ++bucket) {
-      const auto materialist = featureTransformer->transform(pos, transformedFeatures, bucket);
-      const auto positional = network[bucket]->propagate(transformedFeatures);
+    for (IndexType bucket = 0; bucket < LayerStacks; ++bucket)
+    {
+        const auto materialist = featureTransformerBig->transform(pos, transformedFeatures, bucket);
+        const auto positional  = networkBig[bucket]->propagate(transformedFeatures);
 
-      t.psqt[bucket] = static_cast<Value>( materialist / OutputScale );
-      t.positional[bucket] = static_cast<Value>( positional / OutputScale );
+        t.psqt[bucket]       = static_cast<Value>(materialist / OutputScale);
+        t.positional[bucket] = static_cast<Value>(positional / OutputScale);
     }
 
     return t;
-  }
+}
 
-  constexpr std::string_view PieceToChar(" PNBRQK  pnbrqk");
+constexpr std::string_view PieceToChar(" PNBRQK  pnbrqk");
 
 
-  // format_cp_compact() converts a Value into (centi)pawns and writes it in a buffer.
-  // The buffer must have capacity for at least 5 chars.
-  static void format_cp_compact(Value v, char* buffer) {
+// Converts a Value into (centi)pawns and writes it in a buffer.
+// The buffer must have capacity for at least 5 chars.
+static void format_cp_compact(Value v, char* buffer) {
 
     buffer[0] = (v < 0 ? '-' : v > 0 ? '+' : ' ');
 
-    int cp = std::abs(100 * v / UCI::NormalizeToPawnValue);
+    int cp = std::abs(UCI::to_cp(v));
     if (cp >= 10000)
     {
-        buffer[1] = '0' + cp / 10000; cp %= 10000;
-        buffer[2] = '0' + cp / 1000; cp %= 1000;
+        buffer[1] = '0' + cp / 10000;
+        cp %= 10000;
+        buffer[2] = '0' + cp / 1000;
+        cp %= 1000;
         buffer[3] = '0' + cp / 100;
         buffer[4] = ' ';
     }
     else if (cp >= 1000)
     {
-        buffer[1] = '0' + cp / 1000; cp %= 1000;
-        buffer[2] = '0' + cp / 100; cp %= 100;
+        buffer[1] = '0' + cp / 1000;
+        cp %= 1000;
+        buffer[2] = '0' + cp / 100;
+        cp %= 100;
         buffer[3] = '.';
         buffer[4] = '0' + cp / 10;
     }
     else
     {
-        buffer[1] = '0' + cp / 100; cp %= 100;
+        buffer[1] = '0' + cp / 100;
+        cp %= 100;
         buffer[2] = '.';
-        buffer[3] = '0' + cp / 10; cp %= 10;
+        buffer[3] = '0' + cp / 10;
+        cp %= 10;
         buffer[4] = '0' + cp / 1;
     }
-  }
+}
 
 
-  // format_cp_aligned_dot() converts a Value into (centi)pawns, always keeping two decimals.
-  static void format_cp_aligned_dot(Value v, std::stringstream &stream) {
-    const double cp = 1.0 * std::abs(int(v)) / UCI::NormalizeToPawnValue;
+// Converts a Value into pawns, always keeping two decimals
+static void format_cp_aligned_dot(Value v, std::stringstream& stream) {
 
-    stream << (v < 0 ? '-' : v > 0 ? '+' : ' ')
-           << std::setiosflags(std::ios::fixed)
-           << std::setw(6)
-           << std::setprecision(2)
-           << cp;
-  }
+    const double pawns = std::abs(0.01 * UCI::to_cp(v));
+
+    stream << (v < 0   ? '-'
+               : v > 0 ? '+'
+                       : ' ')
+           << std::setiosflags(std::ios::fixed) << std::setw(6) << std::setprecision(2) << pawns;
+}
 
 
-  // trace() returns a string with the value of each piece on a board,
-  // and a table for (PSQT, Layers) values bucket by bucket.
-
-  std::string trace(Position& pos) {
+// Returns a string with the value of each piece on a board,
+// and a table for (PSQT, Layers) values bucket by bucket.
+std::string trace(Position& pos) {
 
     std::stringstream ss;
 
-    char board[3*8+1][8*8+2];
+    char board[3 * 8 + 1][8 * 8 + 2];
     std::memset(board, ' ', sizeof(board));
-    for (int row = 0; row < 3*8+1; ++row)
-      board[row][8*8+1] = '\0';
+    for (int row = 0; row < 3 * 8 + 1; ++row)
+        board[row][8 * 8 + 1] = '\0';
 
     // A lambda to output one box of the board
     auto writeSquare = [&board](File file, Rank rank, Piece pc, Value value) {
-
-      const int x = ((int)file) * 8;
-      const int y = (7 - (int)rank) * 3;
-      for (int i = 1; i < 8; ++i)
-         board[y][x+i] = board[y+3][x+i] = '-';
-      for (int i = 1; i < 3; ++i)
-         board[y+i][x] = board[y+i][x+8] = '|';
-      board[y][x] = board[y][x+8] = board[y+3][x+8] = board[y+3][x] = '+';
-      if (pc != NO_PIECE)
-        board[y+1][x+4] = PieceToChar[pc];
-      if (value != VALUE_NONE)
-        format_cp_compact(value, &board[y+2][x+2]);
+        const int x = int(file) * 8;
+        const int y = (7 - int(rank)) * 3;
+        for (int i = 1; i < 8; ++i)
+            board[y][x + i] = board[y + 3][x + i] = '-';
+        for (int i = 1; i < 3; ++i)
+            board[y + i][x] = board[y + i][x + 8] = '|';
+        board[y][x] = board[y][x + 8] = board[y + 3][x + 8] = board[y + 3][x] = '+';
+        if (pc != NO_PIECE)
+            board[y + 1][x + 4] = PieceToChar[pc];
+        if (value != VALUE_NONE)
+            format_cp_compact(value, &board[y + 2][x + 2]);
     };
 
     // We estimate the value of each piece by doing a differential evaluation from
     // the current base eval, simulating the removal of the piece from its square.
-    Value base = evaluate(pos);
-    base = pos.side_to_move() == WHITE ? base : -base;
+    Value base = evaluate<NNUE::Big>(pos);
+    base       = pos.side_to_move() == WHITE ? base : -base;
 
     for (File f = FILE_A; f <= FILE_H; ++f)
-      for (Rank r = RANK_1; r <= RANK_8; ++r)
-      {
-        Square sq = make_square(f, r);
-        Piece pc = pos.piece_on(sq);
-        Value v = VALUE_NONE;
-
-        if (pc != NO_PIECE && type_of(pc) != KING)
+        for (Rank r = RANK_1; r <= RANK_8; ++r)
         {
-          auto st = pos.state();
+            Square sq = make_square(f, r);
+            Piece  pc = pos.piece_on(sq);
+            Value  v  = VALUE_NONE;
 
-          pos.remove_piece(sq);
-          st->accumulator.computed[WHITE] = false;
-          st->accumulator.computed[BLACK] = false;
+            if (pc != NO_PIECE && type_of(pc) != KING)
+            {
+                auto st = pos.state();
 
-          Value eval = evaluate(pos);
-          eval = pos.side_to_move() == WHITE ? eval : -eval;
-          v = base - eval;
+                pos.remove_piece(sq);
+                st->accumulatorBig.computed[WHITE] = false;
+                st->accumulatorBig.computed[BLACK] = false;
 
-          pos.put_piece(pc, sq);
-          st->accumulator.computed[WHITE] = false;
-          st->accumulator.computed[BLACK] = false;
+                Value eval = evaluate<NNUE::Big>(pos);
+                eval       = pos.side_to_move() == WHITE ? eval : -eval;
+                v          = base - eval;
+
+                pos.put_piece(pc, sq);
+                st->accumulatorBig.computed[WHITE] = false;
+                st->accumulatorBig.computed[BLACK] = false;
+            }
+
+            writeSquare(f, r, pc, v);
         }
 
-        writeSquare(f, r, pc, v);
-      }
-
     ss << " NNUE derived piece values:\n";
-    for (int row = 0; row < 3*8+1; ++row)
+    for (int row = 0; row < 3 * 8 + 1; ++row)
         ss << board[row] << '\n';
     ss << '\n';
 
@@ -338,41 +401,53 @@ namespace Stockfish::Eval::NNUE {
 
     for (std::size_t bucket = 0; bucket < LayerStacks; ++bucket)
     {
-      ss <<  "|  " << bucket    << "        ";
-      ss << " |  "; format_cp_aligned_dot(t.psqt[bucket], ss); ss << "  "
-         << " |  "; format_cp_aligned_dot(t.positional[bucket], ss); ss << "  "
-         << " |  "; format_cp_aligned_dot(t.psqt[bucket] + t.positional[bucket], ss); ss << "  "
-         << " |";
-      if (bucket == t.correctBucket)
-          ss << " <-- this bucket is used";
-      ss << '\n';
+        ss << "|  " << bucket << "        ";
+        ss << " |  ";
+        format_cp_aligned_dot(t.psqt[bucket], ss);
+        ss << "  "
+           << " |  ";
+        format_cp_aligned_dot(t.positional[bucket], ss);
+        ss << "  "
+           << " |  ";
+        format_cp_aligned_dot(t.psqt[bucket] + t.positional[bucket], ss);
+        ss << "  "
+           << " |";
+        if (bucket == t.correctBucket)
+            ss << " <-- this bucket is used";
+        ss << '\n';
     }
 
     ss << "+------------+------------+------------+------------+\n";
 
     return ss.str();
-  }
+}
 
 
-  // Load eval, from a file stream or a memory stream
-  bool load_eval(std::string name, std::istream& stream) {
+// Load eval, from a file stream or a memory stream
+std::optional<std::string> load_eval(std::istream& stream, NetSize netSize) {
 
-    initialize();
-    fileName = name;
-    return read_parameters(stream);
-  }
+    initialize(netSize);
+    std::string netDescription;
+    return read_parameters(stream, netSize, netDescription) ? std::make_optional(netDescription)
+                                                            : std::nullopt;
+}
 
-  // Save eval, to a file stream or a memory stream
-  bool save_eval(std::ostream& stream) {
+// Save eval, to a file stream or a memory stream
+bool save_eval(std::ostream&      stream,
+               NetSize            netSize,
+               const std::string& name,
+               const std::string& netDescription) {
 
-    if (fileName.empty())
-      return false;
+    if (name.empty() || name == "None")
+        return false;
 
-    return write_parameters(stream);
-  }
+    return write_parameters(stream, netSize, netDescription);
+}
 
-  /// Save eval, to a file given by its name
-  bool save_eval(const std::optional<std::string>& filename) {
+// Save eval, to a file given by its name
+bool save_eval(const std::optional<std::string>&                              filename,
+               NetSize                                                        netSize,
+               const std::unordered_map<Eval::NNUE::NetSize, Eval::EvalFile>& evalFiles) {
 
     std::string actualFilename;
     std::string msg;
@@ -381,25 +456,27 @@ namespace Stockfish::Eval::NNUE {
         actualFilename = filename.value();
     else
     {
-        if (currentEvalFileName != EvalFileDefaultName)
+        if (evalFiles.at(netSize).current
+            != (netSize == Small ? EvalFileDefaultNameSmall : EvalFileDefaultNameBig))
         {
-             msg = "Failed to export a net. A non-embedded net can only be saved if the filename is specified";
+            msg = "Failed to export a net. "
+                  "A non-embedded net can only be saved if the filename is specified";
 
-             sync_cout << msg << sync_endl;
-             return false;
+            sync_cout << msg << sync_endl;
+            return false;
         }
-        actualFilename = EvalFileDefaultName;
+        actualFilename = (netSize == Small ? EvalFileDefaultNameSmall : EvalFileDefaultNameBig);
     }
 
     std::ofstream stream(actualFilename, std::ios_base::binary);
-    bool saved = save_eval(stream);
+    bool          saved = save_eval(stream, netSize, evalFiles.at(netSize).current,
+                                    evalFiles.at(netSize).netDescription);
 
-    msg = saved ? "Network saved successfully to " + actualFilename
-                : "Failed to export a net";
+    msg = saved ? "Network saved successfully to " + actualFilename : "Failed to export a net";
 
     sync_cout << msg << sync_endl;
     return saved;
-  }
+}
 
 
-} // namespace Stockfish::Eval::NNUE
+}  // namespace Stockfish::Eval::NNUE

src/nnue/evaluate_nnue.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,48 +21,73 @@
 #ifndef NNUE_EVALUATE_NNUE_H_INCLUDED
 #define NNUE_EVALUATE_NNUE_H_INCLUDED
 
+#include <cstdint>
+#include <iosfwd>
+#include <memory>
+#include <optional>
+#include <string>
+#include <unordered_map>
+
+#include "../misc.h"
+#include "../types.h"
+#include "nnue_architecture.h"
 #include "nnue_feature_transformer.h"
 
-#include <memory>
+namespace Stockfish {
+class Position;
+
+namespace Eval {
+struct EvalFile;
+}
+
+}
 
 namespace Stockfish::Eval::NNUE {
 
-  // Hash value of evaluation function structure
-  constexpr std::uint32_t HashValue =
-      FeatureTransformer::get_hash_value() ^ Network::get_hash_value();
+// Hash value of evaluation function structure
+constexpr std::uint32_t HashValue[2] = {
+  FeatureTransformer<TransformedFeatureDimensionsBig, nullptr>::get_hash_value()
+    ^ Network<TransformedFeatureDimensionsBig, L2Big, L3Big>::get_hash_value(),
+  FeatureTransformer<TransformedFeatureDimensionsSmall, nullptr>::get_hash_value()
+    ^ Network<TransformedFeatureDimensionsSmall, L2Small, L3Small>::get_hash_value()};
 
-
-  // Deleter for automating release of memory area
-  template <typename T>
-  struct AlignedDeleter {
+// Deleter for automating release of memory area
+template<typename T>
+struct AlignedDeleter {
     void operator()(T* ptr) const {
-      ptr->~T();
-      std_aligned_free(ptr);
+        ptr->~T();
+        std_aligned_free(ptr);
     }
-  };
+};
 
-  template <typename T>
-  struct LargePageDeleter {
+template<typename T>
+struct LargePageDeleter {
     void operator()(T* ptr) const {
-      ptr->~T();
-      aligned_large_pages_free(ptr);
+        ptr->~T();
+        aligned_large_pages_free(ptr);
     }
-  };
+};
 
-  template <typename T>
-  using AlignedPtr = std::unique_ptr<T, AlignedDeleter<T>>;
+template<typename T>
+using AlignedPtr = std::unique_ptr<T, AlignedDeleter<T>>;
 
-  template <typename T>
-  using LargePagePtr = std::unique_ptr<T, LargePageDeleter<T>>;
+template<typename T>
+using LargePagePtr = std::unique_ptr<T, LargePageDeleter<T>>;
 
-  std::string trace(Position& pos);
-  Value evaluate(const Position& pos, bool adjusted = false, int* complexity = nullptr);
-  void hint_common_parent_position(const Position& pos);
+std::string trace(Position& pos);
+template<NetSize Net_Size>
+Value evaluate(const Position& pos, bool adjusted = false, int* complexity = nullptr);
+void  hint_common_parent_position(const Position& pos);
 
-  bool load_eval(std::string name, std::istream& stream);
-  bool save_eval(std::ostream& stream);
-  bool save_eval(const std::optional<std::string>& filename);
+std::optional<std::string> load_eval(std::istream& stream, NetSize netSize);
+bool                       save_eval(std::ostream&      stream,
+                                     NetSize            netSize,
+                                     const std::string& name,
+                                     const std::string& netDescription);
+bool                       save_eval(const std::optional<std::string>& filename,
+                                     NetSize                           netSize,
+                                     const std::unordered_map<Eval::NNUE::NetSize, Eval::EvalFile>&);
 
 }  // namespace Stockfish::Eval::NNUE
 
-#endif // #ifndef NNUE_EVALUATE_NNUE_H_INCLUDED
+#endif  // #ifndef NNUE_EVALUATE_NNUE_H_INCLUDED

src/nnue/features/half_ka_v2_hm.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,65 +20,67 @@
 
 #include "half_ka_v2_hm.h"
 
+#include "../../bitboard.h"
 #include "../../position.h"
+#include "../../types.h"
+#include "../nnue_common.h"
 
 namespace Stockfish::Eval::NNUE::Features {
 
-  // Index of a feature for a given king position and another piece on some square
-  template<Color Perspective>
-  inline IndexType HalfKAv2_hm::make_index(Square s, Piece pc, Square ksq) {
-    return IndexType((int(s) ^ OrientTBL[Perspective][ksq]) + PieceSquareIndex[Perspective][pc] + KingBuckets[Perspective][ksq]);
-  }
+// Index of a feature for a given king position and another piece on some square
+template<Color Perspective>
+inline IndexType HalfKAv2_hm::make_index(Square s, Piece pc, Square ksq) {
+    return IndexType((int(s) ^ OrientTBL[Perspective][ksq]) + PieceSquareIndex[Perspective][pc]
+                     + KingBuckets[Perspective][ksq]);
+}
 
-  // Get a list of indices for active features
-  template<Color Perspective>
-  void HalfKAv2_hm::append_active_indices(
-    const Position& pos,
-    IndexList& active
-  ) {
-    Square ksq = pos.square<KING>(Perspective);
-    Bitboard bb = pos.pieces();
+// Get a list of indices for active features
+template<Color Perspective>
+void HalfKAv2_hm::append_active_indices(const Position& pos, IndexList& active) {
+    Square   ksq = pos.square<KING>(Perspective);
+    Bitboard bb  = pos.pieces();
     while (bb)
     {
-      Square s = pop_lsb(bb);
-      active.push_back(make_index<Perspective>(s, pos.piece_on(s), ksq));
+        Square s = pop_lsb(bb);
+        active.push_back(make_index<Perspective>(s, pos.piece_on(s), ksq));
     }
-  }
+}
 
-  // Explicit template instantiations
-  template void HalfKAv2_hm::append_active_indices<WHITE>(const Position& pos, IndexList& active);
-  template void HalfKAv2_hm::append_active_indices<BLACK>(const Position& pos, IndexList& active);
+// Explicit template instantiations
+template void HalfKAv2_hm::append_active_indices<WHITE>(const Position& pos, IndexList& active);
+template void HalfKAv2_hm::append_active_indices<BLACK>(const Position& pos, IndexList& active);
 
-  // append_changed_indices() : get a list of indices for recently changed features
-  template<Color Perspective>
-  void HalfKAv2_hm::append_changed_indices(
-    Square ksq,
-    const DirtyPiece& dp,
-    IndexList& removed,
-    IndexList& added
-  ) {
-    for (int i = 0; i < dp.dirty_num; ++i) {
-      if (dp.from[i] != SQ_NONE)
-        removed.push_back(make_index<Perspective>(dp.from[i], dp.piece[i], ksq));
-      if (dp.to[i] != SQ_NONE)
-        added.push_back(make_index<Perspective>(dp.to[i], dp.piece[i], ksq));
+// Get a list of indices for recently changed features
+template<Color Perspective>
+void HalfKAv2_hm::append_changed_indices(Square            ksq,
+                                         const DirtyPiece& dp,
+                                         IndexList&        removed,
+                                         IndexList&        added) {
+    for (int i = 0; i < dp.dirty_num; ++i)
+    {
+        if (dp.from[i] != SQ_NONE)
+            removed.push_back(make_index<Perspective>(dp.from[i], dp.piece[i], ksq));
+        if (dp.to[i] != SQ_NONE)
+            added.push_back(make_index<Perspective>(dp.to[i], dp.piece[i], ksq));
     }
-  }
+}
 
-  // Explicit template instantiations
-  template void HalfKAv2_hm::append_changed_indices<WHITE>(Square ksq, const DirtyPiece& dp, IndexList& removed, IndexList& added);
-  template void HalfKAv2_hm::append_changed_indices<BLACK>(Square ksq, const DirtyPiece& dp, IndexList& removed, IndexList& added);
+// Explicit template instantiations
+template void HalfKAv2_hm::append_changed_indices<WHITE>(Square            ksq,
+                                                         const DirtyPiece& dp,
+                                                         IndexList&        removed,
+                                                         IndexList&        added);
+template void HalfKAv2_hm::append_changed_indices<BLACK>(Square            ksq,
+                                                         const DirtyPiece& dp,
+                                                         IndexList&        removed,
+                                                         IndexList&        added);
 
-  int HalfKAv2_hm::update_cost(const StateInfo* st) {
-    return st->dirtyPiece.dirty_num;
-  }
+int HalfKAv2_hm::update_cost(const StateInfo* st) { return st->dirtyPiece.dirty_num; }
 
-  int HalfKAv2_hm::refresh_cost(const Position& pos) {
-    return pos.count<ALL_PIECES>();
-  }
+int HalfKAv2_hm::refresh_cost(const Position& pos) { return pos.count<ALL_PIECES>(); }
 
-  bool HalfKAv2_hm::requires_refresh(const StateInfo* st, Color perspective) {
+bool HalfKAv2_hm::requires_refresh(const StateInfo* st, Color perspective) {
     return st->dirtyPiece.piece[0] == make_piece(perspective, KING);
-  }
+}
 
 }  // namespace Stockfish::Eval::NNUE::Features

src/nnue/features/half_ka_v2_hm.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,46 +21,47 @@
 #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
 #define NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
 
+#include <cstdint>
+
+#include "../../misc.h"
+#include "../../types.h"
 #include "../nnue_common.h"
 
-#include "../../evaluate.h"
-#include "../../misc.h"
-
 namespace Stockfish {
-  struct StateInfo;
+struct StateInfo;
+class Position;
 }
 
 namespace Stockfish::Eval::NNUE::Features {
 
-  // Feature HalfKAv2_hm: Combination of the position of own king
-  // and the position of pieces. Position mirrored such that king always on e..h files.
-  class HalfKAv2_hm {
+// Feature HalfKAv2_hm: Combination of the position of own king and the
+// position of pieces. Position mirrored such that king is always on e..h files.
+class HalfKAv2_hm {
 
-    // unique number for each piece type on each square
+    // Unique number for each piece type on each square
     enum {
-      PS_NONE     =  0,
-      PS_W_PAWN   =  0,
-      PS_B_PAWN   =  1 * SQUARE_NB,
-      PS_W_KNIGHT =  2 * SQUARE_NB,
-      PS_B_KNIGHT =  3 * SQUARE_NB,
-      PS_W_BISHOP =  4 * SQUARE_NB,
-      PS_B_BISHOP =  5 * SQUARE_NB,
-      PS_W_ROOK   =  6 * SQUARE_NB,
-      PS_B_ROOK   =  7 * SQUARE_NB,
-      PS_W_QUEEN  =  8 * SQUARE_NB,
-      PS_B_QUEEN  =  9 * SQUARE_NB,
-      PS_KING     = 10 * SQUARE_NB,
-      PS_NB       = 11 * SQUARE_NB
+        PS_NONE     = 0,
+        PS_W_PAWN   = 0,
+        PS_B_PAWN   = 1 * SQUARE_NB,
+        PS_W_KNIGHT = 2 * SQUARE_NB,
+        PS_B_KNIGHT = 3 * SQUARE_NB,
+        PS_W_BISHOP = 4 * SQUARE_NB,
+        PS_B_BISHOP = 5 * SQUARE_NB,
+        PS_W_ROOK   = 6 * SQUARE_NB,
+        PS_B_ROOK   = 7 * SQUARE_NB,
+        PS_W_QUEEN  = 8 * SQUARE_NB,
+        PS_B_QUEEN  = 9 * SQUARE_NB,
+        PS_KING     = 10 * SQUARE_NB,
+        PS_NB       = 11 * SQUARE_NB
     };
 
     static constexpr IndexType PieceSquareIndex[COLOR_NB][PIECE_NB] = {
-      // convention: W - us, B - them
-      // viewed from other side, W and B are reversed
-      { PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE,
-        PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE },
-      { PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE,
-        PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE }
-    };
+      // Convention: W - us, B - them
+      // Viewed from other side, W and B are reversed
+      {PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE,
+       PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE},
+      {PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE,
+       PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE}};
 
     // Index of a feature for a given king position and another piece on some square
     template<Color Perspective>
@@ -75,9 +76,10 @@ namespace Stockfish::Eval::NNUE::Features {
 
     // Number of feature dimensions
     static constexpr IndexType Dimensions =
-        static_cast<IndexType>(SQUARE_NB) * static_cast<IndexType>(PS_NB) / 2;
+      static_cast<IndexType>(SQUARE_NB) * static_cast<IndexType>(PS_NB) / 2;
 
 #define B(v) (v * PS_NB)
+    // clang-format off
     static constexpr int KingBuckets[COLOR_NB][SQUARE_NB] = {
       { B(28), B(29), B(30), B(31), B(31), B(30), B(29), B(28),
         B(24), B(25), B(26), B(27), B(27), B(26), B(25), B(24),
@@ -96,8 +98,9 @@ namespace Stockfish::Eval::NNUE::Features {
         B(24), B(25), B(26), B(27), B(27), B(26), B(25), B(24),
         B(28), B(29), B(30), B(31), B(31), B(30), B(29), B(28) }
     };
+    // clang-format on
 #undef B
-
+    // clang-format off
     // Orient a square according to perspective (rotates by 180 for black)
     static constexpr int OrientTBL[COLOR_NB][SQUARE_NB] = {
       { SQ_H1, SQ_H1, SQ_H1, SQ_H1, SQ_A1, SQ_A1, SQ_A1, SQ_A1,
@@ -117,36 +120,31 @@ namespace Stockfish::Eval::NNUE::Features {
         SQ_H8, SQ_H8, SQ_H8, SQ_H8, SQ_A8, SQ_A8, SQ_A8, SQ_A8,
         SQ_H8, SQ_H8, SQ_H8, SQ_H8, SQ_A8, SQ_A8, SQ_A8, SQ_A8 }
     };
+    // clang-format on
 
     // Maximum number of simultaneously active features.
     static constexpr IndexType MaxActiveDimensions = 32;
-    using IndexList = ValueList<IndexType, MaxActiveDimensions>;
+    using IndexList                                = ValueList<IndexType, MaxActiveDimensions>;
 
     // Get a list of indices for active features
     template<Color Perspective>
-    static void append_active_indices(
-      const Position& pos,
-      IndexList& active);
+    static void append_active_indices(const Position& pos, IndexList& active);
 
     // Get a list of indices for recently changed features
     template<Color Perspective>
-    static void append_changed_indices(
-      Square ksq,
-      const DirtyPiece& dp,
-      IndexList& removed,
-      IndexList& added
-    );
+    static void
+    append_changed_indices(Square ksq, const DirtyPiece& dp, IndexList& removed, IndexList& added);
 
     // Returns the cost of updating one perspective, the most costly one.
     // Assumes no refresh needed.
     static int update_cost(const StateInfo* st);
     static int refresh_cost(const Position& pos);
 
-    // Returns whether the change stored in this StateInfo means that
-    // a full accumulator refresh is required.
+    // Returns whether the change stored in this StateInfo means
+    // that a full accumulator refresh is required.
     static bool requires_refresh(const StateInfo* st, Color perspective);
-  };
+};
 
 }  // namespace Stockfish::Eval::NNUE::Features
 
-#endif // #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
+#endif  // #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED

src/nnue/layers/affine_transform.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,33 +21,18 @@
 #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
 #define NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
 
+#include <cstdint>
 #include <iostream>
-#include <algorithm>
-#include <type_traits>
+
 #include "../nnue_common.h"
 #include "simd.h"
 
 /*
   This file contains the definition for a fully connected layer (aka affine transform).
-  Two approaches are employed, depending on the sizes of the transform.
 
-  Approach 1 (a specialization for large inputs):
-    - used when the PaddedInputDimensions >= 128
-    - uses AVX512 if possible
-    - processes inputs in batches of 2*InputSimdWidth
-      - so in batches of 128 for AVX512
-    - the weight blocks of size InputSimdWidth are transposed such that
-      access is sequential
-    - N columns of the weight matrix are processed a time, where N
-      depends on the architecture (the amount of registers)
-    - accumulate + hadd is used
-
-  Approach 2 (a specialization for small inputs):
-    - used when the PaddedInputDimensions < 128
     - expected use-case is for when PaddedInputDimensions == 32 and InputDimensions <= 32.
       - that's why AVX512 is hard to implement
     - expected use-case is small layers
-      - not optimized as well as the approach 1
     - inputs are processed in chunks of 4, weights are respectively transposed
     - accumulation happens directly to int32s
 */
@@ -55,129 +40,104 @@
 namespace Stockfish::Eval::NNUE::Layers {
 
 // Fallback implementation for older/other architectures.
-// Identical for both approaches. Requires the input to be padded to at least 16 values.
+// Requires the input to be padded to at least 16 values.
 #if !defined(USE_SSSE3)
-  template <IndexType InputDimensions, IndexType PaddedInputDimensions, IndexType OutputDimensions>
-  static void affine_transform_non_ssse3(std::int32_t* output, const std::int8_t* weights, const std::int32_t* biases, const std::uint8_t* input)
-  {
-# if defined(USE_SSE2)
+template<IndexType InputDimensions, IndexType PaddedInputDimensions, IndexType OutputDimensions>
+static void affine_transform_non_ssse3(std::int32_t*       output,
+                                       const std::int8_t*  weights,
+                                       const std::int32_t* biases,
+                                       const std::uint8_t* input) {
+    #if defined(USE_SSE2) || defined(USE_NEON_DOTPROD) || defined(USE_NEON)
+        #if defined(USE_SSE2)
     // At least a multiple of 16, with SSE2.
-    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
-    const __m128i Zeros = _mm_setzero_si128();
-    const auto inputVector = reinterpret_cast<const __m128i*>(input);
+    constexpr IndexType NumChunks   = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
+    const __m128i       Zeros       = _mm_setzero_si128();
+    const auto          inputVector = reinterpret_cast<const __m128i*>(input);
 
-# elif defined(USE_MMX)
-    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / 8;
-    const __m64 Zeros = _mm_setzero_si64();
-    const auto inputVector = reinterpret_cast<const __m64*>(input);
+        #elif defined(USE_NEON_DOTPROD)
+    constexpr IndexType NumChunks   = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
+    const auto          inputVector = reinterpret_cast<const int8x16_t*>(input);
 
-# elif defined(USE_NEON_DOTPROD)
-    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
-    const auto inputVector = reinterpret_cast<const int8x16_t*>(input);
+        #elif defined(USE_NEON)
+    constexpr IndexType NumChunks   = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
+    const auto          inputVector = reinterpret_cast<const int8x8_t*>(input);
+        #endif
 
-# elif defined(USE_NEON)
-    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
-    const auto inputVector = reinterpret_cast<const int8x8_t*>(input);
-# endif
+    for (IndexType i = 0; i < OutputDimensions; ++i)
+    {
+        const IndexType offset = i * PaddedInputDimensions;
 
-    for (IndexType i = 0; i < OutputDimensions; ++i) {
-      const IndexType offset = i * PaddedInputDimensions;
+        #if defined(USE_SSE2)
+        __m128i    sumLo = _mm_cvtsi32_si128(biases[i]);
+        __m128i    sumHi = Zeros;
+        const auto row   = reinterpret_cast<const __m128i*>(&weights[offset]);
+        for (IndexType j = 0; j < NumChunks; ++j)
+        {
+            __m128i row_j           = _mm_load_si128(&row[j]);
+            __m128i input_j         = _mm_load_si128(&inputVector[j]);
+            __m128i extendedRowLo   = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
+            __m128i extendedRowHi   = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
+            __m128i extendedInputLo = _mm_unpacklo_epi8(input_j, Zeros);
+            __m128i extendedInputHi = _mm_unpackhi_epi8(input_j, Zeros);
+            __m128i productLo       = _mm_madd_epi16(extendedRowLo, extendedInputLo);
+            __m128i productHi       = _mm_madd_epi16(extendedRowHi, extendedInputHi);
+            sumLo                   = _mm_add_epi32(sumLo, productLo);
+            sumHi                   = _mm_add_epi32(sumHi, productHi);
+        }
+        __m128i sum           = _mm_add_epi32(sumLo, sumHi);
+        __m128i sumHigh_64    = _mm_shuffle_epi32(sum, _MM_SHUFFLE(1, 0, 3, 2));
+        sum                   = _mm_add_epi32(sum, sumHigh_64);
+        __m128i sum_second_32 = _mm_shufflelo_epi16(sum, _MM_SHUFFLE(1, 0, 3, 2));
+        sum                   = _mm_add_epi32(sum, sum_second_32);
+        output[i]             = _mm_cvtsi128_si32(sum);
 
-# if defined(USE_SSE2)
-      __m128i sumLo = _mm_cvtsi32_si128(biases[i]);
-      __m128i sumHi = Zeros;
-      const auto row = reinterpret_cast<const __m128i*>(&weights[offset]);
-      for (IndexType j = 0; j < NumChunks; ++j) {
-        __m128i row_j = _mm_load_si128(&row[j]);
-        __m128i input_j = _mm_load_si128(&inputVector[j]);
-        __m128i extendedRowLo = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
-        __m128i extendedRowHi = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
-        __m128i extendedInputLo = _mm_unpacklo_epi8(input_j, Zeros);
-        __m128i extendedInputHi = _mm_unpackhi_epi8(input_j, Zeros);
-        __m128i productLo = _mm_madd_epi16(extendedRowLo, extendedInputLo);
-        __m128i productHi = _mm_madd_epi16(extendedRowHi, extendedInputHi);
-        sumLo = _mm_add_epi32(sumLo, productLo);
-        sumHi = _mm_add_epi32(sumHi, productHi);
-      }
-      __m128i sum = _mm_add_epi32(sumLo, sumHi);
-      __m128i sumHigh_64 = _mm_shuffle_epi32(sum, _MM_SHUFFLE(1, 0, 3, 2));
-      sum = _mm_add_epi32(sum, sumHigh_64);
-      __m128i sum_second_32 = _mm_shufflelo_epi16(sum, _MM_SHUFFLE(1, 0, 3, 2));
-      sum = _mm_add_epi32(sum, sum_second_32);
-      output[i] = _mm_cvtsi128_si32(sum);
+        #elif defined(USE_NEON_DOTPROD)
+        int32x4_t  sum = {biases[i]};
+        const auto row = reinterpret_cast<const int8x16_t*>(&weights[offset]);
+        for (IndexType j = 0; j < NumChunks; ++j)
+        {
+            sum = vdotq_s32(sum, inputVector[j], row[j]);
+        }
+        output[i] = vaddvq_s32(sum);
 
-# elif defined(USE_MMX)
-      __m64 sumLo = _mm_cvtsi32_si64(biases[i]);
-      __m64 sumHi = Zeros;
-      const auto row = reinterpret_cast<const __m64*>(&weights[offset]);
-      for (IndexType j = 0; j < NumChunks; ++j) {
-        __m64 row_j = row[j];
-        __m64 input_j = inputVector[j];
-        __m64 extendedRowLo = _mm_srai_pi16(_mm_unpacklo_pi8(row_j, row_j), 8);
-        __m64 extendedRowHi = _mm_srai_pi16(_mm_unpackhi_pi8(row_j, row_j), 8);
-        __m64 extendedInputLo = _mm_unpacklo_pi8(input_j, Zeros);
-        __m64 extendedInputHi = _mm_unpackhi_pi8(input_j, Zeros);
-        __m64 productLo = _mm_madd_pi16(extendedRowLo, extendedInputLo);
-        __m64 productHi = _mm_madd_pi16(extendedRowHi, extendedInputHi);
-        sumLo = _mm_add_pi32(sumLo, productLo);
-        sumHi = _mm_add_pi32(sumHi, productHi);
-      }
-      __m64 sum = _mm_add_pi32(sumLo, sumHi);
-      sum = _mm_add_pi32(sum, _mm_unpackhi_pi32(sum, sum));
-      output[i] = _mm_cvtsi64_si32(sum);
+        #elif defined(USE_NEON)
+        int32x4_t  sum = {biases[i]};
+        const auto row = reinterpret_cast<const int8x8_t*>(&weights[offset]);
+        for (IndexType j = 0; j < NumChunks; ++j)
+        {
+            int16x8_t product = vmull_s8(inputVector[j * 2], row[j * 2]);
+            product           = vmlal_s8(product, inputVector[j * 2 + 1], row[j * 2 + 1]);
+            sum               = vpadalq_s16(sum, product);
+        }
+        output[i] = sum[0] + sum[1] + sum[2] + sum[3];
 
-# elif defined(USE_NEON_DOTPROD)
-      int32x4_t sum = {biases[i]};
-      const auto row = reinterpret_cast<const int8x16_t*>(&weights[offset]);
-      for (IndexType j = 0; j < NumChunks; ++j) {
-        sum = vdotq_s32(sum, inputVector[j], row[j]);
-      }
-      output[i] = vaddvq_s32(sum);
-
-# elif defined(USE_NEON)
-      int32x4_t sum = {biases[i]};
-      const auto row = reinterpret_cast<const int8x8_t*>(&weights[offset]);
-      for (IndexType j = 0; j < NumChunks; ++j) {
-        int16x8_t product = vmull_s8(inputVector[j * 2], row[j * 2]);
-        product = vmlal_s8(product, inputVector[j * 2 + 1], row[j * 2 + 1]);
-        sum = vpadalq_s16(sum, product);
-      }
-      output[i] = sum[0] + sum[1] + sum[2] + sum[3];
-
-# else
-      std::int32_t sum = biases[i];
-      for (IndexType j = 0; j < InputDimensions; ++j) {
-        sum += weights[offset + j] * input[j];
-      }
-      output[i] = sum;
-# endif
+        #endif
     }
+    #else
+    std::memcpy(output, biases, sizeof(std::int32_t) * OutputDimensions);
 
-# if defined(USE_MMX)
-    _mm_empty();
-# endif
-  }
+    // Traverse weights in transpose order to take advantage of input sparsity
+    for (IndexType i = 0; i < InputDimensions; ++i)
+        if (input[i])
+        {
+            const std::int8_t* w  = &weights[i];
+            const int          in = input[i];
+            for (IndexType j = 0; j < OutputDimensions; ++j)
+                output[j] += w[j * PaddedInputDimensions] * in;
+        }
+    #endif
+}
 #endif
 
-  template <IndexType InDims, IndexType OutDims, typename Enabled = void>
-  class AffineTransform;
-
-#if defined (USE_AVX512)
-  constexpr IndexType LargeInputSize = 2 * 64;
-#else
-  constexpr IndexType LargeInputSize = std::numeric_limits<IndexType>::max();
-#endif
-
-  // A specialization for large inputs
-  template <IndexType InDims, IndexType OutDims>
-  class AffineTransform<InDims, OutDims, std::enable_if_t<(ceil_to_multiple<IndexType>(InDims, MaxSimdWidth) >= LargeInputSize)>> {
+template<IndexType InDims, IndexType OutDims>
+class AffineTransform {
    public:
     // Input/output type
-    using InputType = std::uint8_t;
+    using InputType  = std::uint8_t;
     using OutputType = std::int32_t;
 
     // Number of input/output dimensions
-    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType InputDimensions  = InDims;
     static constexpr IndexType OutputDimensions = OutDims;
 
     static constexpr IndexType PaddedInputDimensions =
@@ -187,377 +147,162 @@ namespace Stockfish::Eval::NNUE::Layers {
 
     using OutputBuffer = OutputType[PaddedOutputDimensions];
 
-    static_assert(PaddedInputDimensions >= LargeInputSize, "Something went wrong. This specialization (for large inputs) should not have been chosen.");
-
-#if defined (USE_AVX512)
-    static constexpr IndexType InputSimdWidth = 64;
-    static constexpr IndexType MaxNumOutputRegs = 16;
-#elif defined (USE_AVX2)
-    static constexpr IndexType InputSimdWidth = 32;
-    static constexpr IndexType MaxNumOutputRegs = 8;
-#elif defined (USE_SSSE3)
-    static constexpr IndexType InputSimdWidth = 16;
-    static constexpr IndexType MaxNumOutputRegs = 8;
-#elif defined (USE_NEON_DOTPROD)
-    static constexpr IndexType InputSimdWidth = 16;
-    static constexpr IndexType MaxNumOutputRegs = 8;
-#elif defined (USE_NEON)
-    static constexpr IndexType InputSimdWidth = 8;
-    static constexpr IndexType MaxNumOutputRegs = 8;
-#else
-    // The fallback implementation will not have permuted weights.
-    // We define these to avoid a lot of ifdefs later.
-    static constexpr IndexType InputSimdWidth = 1;
-    static constexpr IndexType MaxNumOutputRegs = 1;
-#endif
-
-    // A big block is a region in the weight matrix of the size [PaddedInputDimensions, NumOutputRegs].
-    // A small block is a region of size [InputSimdWidth, 1]
-
-    static constexpr IndexType NumOutputRegs = std::min(MaxNumOutputRegs, OutputDimensions);
-    static constexpr IndexType SmallBlockSize = InputSimdWidth;
-    static constexpr IndexType BigBlockSize = NumOutputRegs * PaddedInputDimensions;
-    static constexpr IndexType NumSmallBlocksInBigBlock = BigBlockSize / SmallBlockSize;
-    static constexpr IndexType NumSmallBlocksPerOutput = PaddedInputDimensions / SmallBlockSize;
-    static constexpr IndexType NumBigBlocks = OutputDimensions / NumOutputRegs;
-
-    static_assert(OutputDimensions % NumOutputRegs == 0);
-
     // Hash value embedded in the evaluation file
     static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hashValue = 0xCC03DAE4u;
-      hashValue += OutputDimensions;
-      hashValue ^= prevHash >> 1;
-      hashValue ^= prevHash << 31;
-      return hashValue;
+        std::uint32_t hashValue = 0xCC03DAE4u;
+        hashValue += OutputDimensions;
+        hashValue ^= prevHash >> 1;
+        hashValue ^= prevHash << 31;
+        return hashValue;
     }
 
-    /*
-      Transposes the small blocks within a block.
-      Effectively means that weights can be traversed sequentially during inference.
-    */
-    static IndexType get_weight_index(IndexType i)
-    {
-      const IndexType smallBlock = (i / SmallBlockSize) % NumSmallBlocksInBigBlock;
-      const IndexType smallBlockCol = smallBlock / NumSmallBlocksPerOutput;
-      const IndexType smallBlockRow = smallBlock % NumSmallBlocksPerOutput;
-      const IndexType bigBlock   = i / BigBlockSize;
-      const IndexType rest       = i % SmallBlockSize;
-
-      const IndexType idx =
-          bigBlock * BigBlockSize
-        + smallBlockRow * SmallBlockSize * NumOutputRegs
-        + smallBlockCol * SmallBlockSize
-        + rest;
-
-      return idx;
+    static constexpr IndexType get_weight_index_scrambled(IndexType i) {
+        return (i / 4) % (PaddedInputDimensions / 4) * OutputDimensions * 4
+             + i / PaddedInputDimensions * 4 + i % 4;
     }
 
-    // Read network parameters
-    bool read_parameters(std::istream& stream) {
-      read_little_endian<BiasType>(stream, biases, OutputDimensions);
-
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
-
-      return !stream.fail();
-    }
-
-    // Write network parameters
-    bool write_parameters(std::ostream& stream) const {
-      write_little_endian<BiasType>(stream, biases, OutputDimensions);
-
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
-
-      return !stream.fail();
-    }
-
-    // Forward propagation
-    const OutputType* propagate(
-        const InputType* input, OutputType* output) const {
-
-#if defined (USE_AVX512)
-      using acc_vec_t = __m512i;
-      using bias_vec_t = __m128i;
-      using weight_vec_t = __m512i;
-      using in_vec_t = __m512i;
-      #define vec_zero _mm512_setzero_si512()
-      #define vec_add_dpbusd_32x2 Simd::m512_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m512_hadd
-      #define vec_haddx4 Simd::m512_haddx4
-#elif defined (USE_AVX2)
-      using acc_vec_t = __m256i;
-      using bias_vec_t = __m128i;
-      using weight_vec_t = __m256i;
-      using in_vec_t = __m256i;
-      #define vec_zero _mm256_setzero_si256()
-      #define vec_add_dpbusd_32x2 Simd::m256_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m256_hadd
-      #define vec_haddx4 Simd::m256_haddx4
-#elif defined (USE_SSSE3)
-      using acc_vec_t = __m128i;
-      using bias_vec_t = __m128i;
-      using weight_vec_t = __m128i;
-      using in_vec_t = __m128i;
-      #define vec_zero _mm_setzero_si128()
-      #define vec_add_dpbusd_32x2 Simd::m128_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m128_hadd
-      #define vec_haddx4 Simd::m128_haddx4
-#elif defined (USE_NEON_DOTPROD)
-      using acc_vec_t = int32x4_t;
-      using bias_vec_t = int32x4_t;
-      using weight_vec_t = int8x16_t;
-      using in_vec_t = int8x16_t;
-      #define vec_zero {0}
-      #define vec_add_dpbusd_32x2 Simd::dotprod_m128_add_dpbusd_epi32x2
-      #define vec_hadd Simd::neon_m128_hadd
-      #define vec_haddx4 Simd::neon_m128_haddx4
-#elif defined (USE_NEON)
-      using acc_vec_t = int32x4_t;
-      using bias_vec_t = int32x4_t;
-      using weight_vec_t = int8x8_t;
-      using in_vec_t = int8x8_t;
-      #define vec_zero {0}
-      #define vec_add_dpbusd_32x2 Simd::neon_m128_add_dpbusd_epi32x2
-      #define vec_hadd Simd::neon_m128_hadd
-      #define vec_haddx4 Simd::neon_m128_haddx4
-#endif
-
-#if defined (USE_SSSE3) || defined (USE_NEON)
-      const in_vec_t* invec = reinterpret_cast<const in_vec_t*>(input);
-
-      // Perform accumulation to registers for each big block
-      for (IndexType bigBlock = 0; bigBlock < NumBigBlocks; ++bigBlock)
-      {
-        acc_vec_t acc[NumOutputRegs] = { vec_zero };
-
-        // Each big block has NumOutputRegs small blocks in each "row", one per register.
-        // We process two small blocks at a time to save on one addition without VNNI.
-        for (IndexType smallBlock = 0; smallBlock < NumSmallBlocksPerOutput; smallBlock += 2)
-        {
-          const weight_vec_t* weightvec =
-            reinterpret_cast<const weight_vec_t*>(
-                weights
-              + bigBlock * BigBlockSize
-              + smallBlock * SmallBlockSize * NumOutputRegs);
-
-          const in_vec_t in0 = invec[smallBlock + 0];
-          const in_vec_t in1 = invec[smallBlock + 1];
-
-          for (IndexType k = 0; k < NumOutputRegs; ++k)
-            vec_add_dpbusd_32x2(acc[k], in0, weightvec[k], in1, weightvec[k + NumOutputRegs]);
-        }
-
-        // Horizontally add all accumulators.
-        if constexpr (NumOutputRegs % 4 == 0)
-        {
-          bias_vec_t* outputvec = reinterpret_cast<bias_vec_t*>(output);
-          const bias_vec_t* biasvec = reinterpret_cast<const bias_vec_t*>(biases);
-
-          for (IndexType k = 0; k < NumOutputRegs; k += 4)
-          {
-            const IndexType idx = (bigBlock * NumOutputRegs + k) / 4;
-            outputvec[idx] = vec_haddx4(acc[k+0], acc[k+1], acc[k+2], acc[k+3], biasvec[idx]);
-          }
-        }
-        else
-        {
-          for (IndexType k = 0; k < NumOutputRegs; ++k)
-          {
-            const IndexType idx = (bigBlock * NumOutputRegs + k);
-            output[idx] = vec_hadd(acc[k], biases[idx]);
-          }
-        }
-      }
-
-# undef vec_zero
-# undef vec_add_dpbusd_32x2
-# undef vec_hadd
-# undef vec_haddx4
+    static constexpr IndexType get_weight_index(IndexType i) {
+#if defined(USE_SSSE3)
+        return get_weight_index_scrambled(i);
 #else
-      // Use old implementation for the other architectures.
-      affine_transform_non_ssse3<
-        InputDimensions,
-        PaddedInputDimensions,
-        OutputDimensions>(output, weights, biases, input);
-
-#endif
-
-      return output;
-    }
-
-   private:
-    using BiasType = OutputType;
-    using WeightType = std::int8_t;
-
-    alignas(CacheLineSize) BiasType biases[OutputDimensions];
-    alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
-  };
-
-  // A specialization for small inputs
-  template <IndexType InDims, IndexType OutDims>
-  class AffineTransform<InDims, OutDims, std::enable_if_t<(ceil_to_multiple<IndexType>(InDims, MaxSimdWidth) < LargeInputSize)>> {
-   public:
-    // Input/output type
-    // Input/output type
-    using InputType = std::uint8_t;
-    using OutputType = std::int32_t;
-
-    // Number of input/output dimensions
-    static constexpr IndexType InputDimensions = InDims;
-    static constexpr IndexType OutputDimensions = OutDims;
-
-    static constexpr IndexType PaddedInputDimensions =
-      ceil_to_multiple<IndexType>(InputDimensions, MaxSimdWidth);
-    static constexpr IndexType PaddedOutputDimensions =
-      ceil_to_multiple<IndexType>(OutputDimensions, MaxSimdWidth);
-
-    using OutputBuffer = OutputType[PaddedOutputDimensions];
-
-    static_assert(PaddedInputDimensions < LargeInputSize, "Something went wrong. This specialization (for small inputs) should not have been chosen.");
-
-    // Hash value embedded in the evaluation file
-    static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hashValue = 0xCC03DAE4u;
-      hashValue += OutputDimensions;
-      hashValue ^= prevHash >> 1;
-      hashValue ^= prevHash << 31;
-      return hashValue;
-    }
-
-    static IndexType get_weight_index_scrambled(IndexType i)
-    {
-      return
-        (i / 4) % (PaddedInputDimensions / 4) * OutputDimensions * 4 +
-        i / PaddedInputDimensions * 4 +
-        i % 4;
-    }
-
-    static IndexType get_weight_index(IndexType i)
-    {
-#if defined (USE_SSSE3)
-      return get_weight_index_scrambled(i);
-#else
-      return i;
+        return i;
 #endif
     }
 
     // Read network parameters
     bool read_parameters(std::istream& stream) {
-      read_little_endian<BiasType>(stream, biases, OutputDimensions);
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
+        read_little_endian<BiasType>(stream, biases, OutputDimensions);
+        for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+            weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
 
-      return !stream.fail();
+        return !stream.fail();
     }
 
     // Write network parameters
     bool write_parameters(std::ostream& stream) const {
-      write_little_endian<BiasType>(stream, biases, OutputDimensions);
+        write_little_endian<BiasType>(stream, biases, OutputDimensions);
 
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
+        for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+            write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
 
-      return !stream.fail();
+        return !stream.fail();
     }
     // Forward propagation
-    const OutputType* propagate(
-        const InputType* input, OutputType* output) const {
+    void propagate(const InputType* input, OutputType* output) const {
 
-#if defined (USE_AVX512)
-      using vec_t = __m512i;
-      #define vec_setzero _mm512_setzero_si512
-      #define vec_set_32 _mm512_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m512_add_dpbusd_epi32
-      #define vec_add_dpbusd_32x2 Simd::m512_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m512_hadd
-#elif defined (USE_AVX2)
-      using vec_t = __m256i;
-      #define vec_setzero _mm256_setzero_si256
-      #define vec_set_32 _mm256_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
-      #define vec_add_dpbusd_32x2 Simd::m256_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m256_hadd
-#elif defined (USE_SSSE3)
-      using vec_t = __m128i;
-      #define vec_setzero _mm_setzero_si128
-      #define vec_set_32 _mm_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
-      #define vec_add_dpbusd_32x2 Simd::m128_add_dpbusd_epi32x2
-      #define vec_hadd Simd::m128_hadd
-#endif
+#if defined(USE_SSSE3)
 
-#if defined (USE_SSSE3)
-      const auto inputVector = reinterpret_cast<const vec_t*>(input);
-
-      static constexpr IndexType OutputSimdWidth = sizeof(vec_t) / sizeof(OutputType);
-
-      static_assert(OutputDimensions % OutputSimdWidth == 0 || OutputDimensions == 1);
-
-      if constexpr (OutputDimensions % OutputSimdWidth == 0)
-      {
-        constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / 4;
-        constexpr IndexType NumRegs = OutputDimensions / OutputSimdWidth;
-
-        const auto input32 = reinterpret_cast<const std::int32_t*>(input);
-        const vec_t* biasvec = reinterpret_cast<const vec_t*>(biases);
-        vec_t acc[NumRegs];
-        for (IndexType k = 0; k < NumRegs; ++k)
-          acc[k] = biasvec[k];
-
-        for (IndexType i = 0; i < NumChunks; i += 2)
+        if constexpr (OutputDimensions > 1)
         {
-          const vec_t in0 = vec_set_32(input32[i + 0]);
-          const vec_t in1 = vec_set_32(input32[i + 1]);
-          const auto col0 = reinterpret_cast<const vec_t*>(&weights[(i + 0) * OutputDimensions * 4]);
-          const auto col1 = reinterpret_cast<const vec_t*>(&weights[(i + 1) * OutputDimensions * 4]);
-          for (IndexType k = 0; k < NumRegs; ++k)
-            vec_add_dpbusd_32x2(acc[k], in0, col0[k], in1, col1[k]);
+
+    #if defined(USE_AVX512)
+            using vec_t = __m512i;
+        #define vec_setzero _mm512_setzero_si512
+        #define vec_set_32 _mm512_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m512_add_dpbusd_epi32
+        #define vec_hadd Simd::m512_hadd
+    #elif defined(USE_AVX2)
+            using vec_t = __m256i;
+        #define vec_setzero _mm256_setzero_si256
+        #define vec_set_32 _mm256_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
+        #define vec_hadd Simd::m256_hadd
+    #elif defined(USE_SSSE3)
+            using vec_t = __m128i;
+        #define vec_setzero _mm_setzero_si128
+        #define vec_set_32 _mm_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
+        #define vec_hadd Simd::m128_hadd
+    #endif
+
+            static constexpr IndexType OutputSimdWidth = sizeof(vec_t) / sizeof(OutputType);
+
+            static_assert(OutputDimensions % OutputSimdWidth == 0);
+
+            constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / 4;
+            constexpr IndexType NumRegs   = OutputDimensions / OutputSimdWidth;
+
+            const auto   input32 = reinterpret_cast<const std::int32_t*>(input);
+            const vec_t* biasvec = reinterpret_cast<const vec_t*>(biases);
+            vec_t        acc[NumRegs];
+            for (IndexType k = 0; k < NumRegs; ++k)
+                acc[k] = biasvec[k];
+
+            for (IndexType i = 0; i < NumChunks; ++i)
+            {
+                const vec_t in0 = vec_set_32(input32[i]);
+                const auto  col0 =
+                  reinterpret_cast<const vec_t*>(&weights[i * OutputDimensions * 4]);
+
+                for (IndexType k = 0; k < NumRegs; ++k)
+                    vec_add_dpbusd_32(acc[k], in0, col0[k]);
+            }
+
+            vec_t* outptr = reinterpret_cast<vec_t*>(output);
+            for (IndexType k = 0; k < NumRegs; ++k)
+                outptr[k] = acc[k];
+
+    #undef vec_setzero
+    #undef vec_set_32
+    #undef vec_add_dpbusd_32
+    #undef vec_hadd
         }
-
-        vec_t* outptr = reinterpret_cast<vec_t*>(output);
-        for (IndexType k = 0; k < NumRegs; ++k)
-          outptr[k] = acc[k];
-      }
-      else if constexpr (OutputDimensions == 1)
-      {
-        constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
-        vec_t sum0 = vec_setzero();
-        const auto row0 = reinterpret_cast<const vec_t*>(&weights[0]);
-
-        for (int j = 0; j < (int)NumChunks; ++j)
+        else if constexpr (OutputDimensions == 1)
         {
-          const vec_t in = inputVector[j];
-          vec_add_dpbusd_32(sum0, in, row0[j]);
-        }
-        output[0] = vec_hadd(sum0, biases[0]);
-      }
 
-# undef vec_setzero
-# undef vec_set_32
-# undef vec_add_dpbusd_32
-# undef vec_add_dpbusd_32x2
-# undef vec_hadd
+    // We cannot use AVX512 for the last layer because there are only 32 inputs
+    // and the buffer is not padded to 64 elements.
+    #if defined(USE_AVX2)
+            using vec_t = __m256i;
+        #define vec_setzero _mm256_setzero_si256
+        #define vec_set_32 _mm256_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
+        #define vec_hadd Simd::m256_hadd
+    #elif defined(USE_SSSE3)
+            using vec_t = __m128i;
+        #define vec_setzero _mm_setzero_si128
+        #define vec_set_32 _mm_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
+        #define vec_hadd Simd::m128_hadd
+    #endif
+
+            const auto inputVector = reinterpret_cast<const vec_t*>(input);
+
+            static constexpr IndexType InputSimdWidth = sizeof(vec_t) / sizeof(InputType);
+
+            static_assert(PaddedInputDimensions % InputSimdWidth == 0);
+
+            constexpr IndexType NumChunks = PaddedInputDimensions / InputSimdWidth;
+            vec_t               sum0      = vec_setzero();
+            const auto          row0      = reinterpret_cast<const vec_t*>(&weights[0]);
+
+            for (int j = 0; j < int(NumChunks); ++j)
+            {
+                const vec_t in = inputVector[j];
+                vec_add_dpbusd_32(sum0, in, row0[j]);
+            }
+            output[0] = vec_hadd(sum0, biases[0]);
+
+    #undef vec_setzero
+    #undef vec_set_32
+    #undef vec_add_dpbusd_32
+    #undef vec_hadd
+        }
 #else
-      // Use old implementation for the other architectures.
-      affine_transform_non_ssse3<
-        InputDimensions,
-        PaddedInputDimensions,
-        OutputDimensions>(output, weights, biases, input);
+        // Use old implementation for the other architectures.
+        affine_transform_non_ssse3<InputDimensions, PaddedInputDimensions, OutputDimensions>(
+          output, weights, biases, input);
 #endif
-
-      return output;
     }
 
    private:
-    using BiasType = OutputType;
+    using BiasType   = OutputType;
     using WeightType = std::int8_t;
 
     alignas(CacheLineSize) BiasType biases[OutputDimensions];
     alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
-  };
+};
 
 }  // namespace Stockfish::Eval::NNUE::Layers
 
-#endif // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
+#endif  // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED

src/nnue/layers/affine_transform_sparse_input.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,10 +21,12 @@
 #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_SPARSE_INPUT_H_INCLUDED
 #define NNUE_LAYERS_AFFINE_TRANSFORM_SPARSE_INPUT_H_INCLUDED
 
-#include <iostream>
 #include <algorithm>
 #include <array>
-#include <type_traits>
+#include <cstdint>
+#include <iostream>
+
+#include "../../bitboard.h"
 #include "../nnue_common.h"
 #include "affine_transform.h"
 #include "simd.h"
@@ -34,130 +36,119 @@
 */
 
 namespace Stockfish::Eval::NNUE::Layers {
-#if defined(__GNUC__)  // GCC, Clang, ICC
 
-  static inline IndexType lsb_(std::uint32_t b) {
-    assert(b);
-    return IndexType(__builtin_ctzl(b));
-  }
-
-#elif defined(_MSC_VER)  // MSVC
-
-  static inline IndexType lsb_(std::uint32_t b) {
-    assert(b);
-    unsigned long idx;
-    _BitScanForward(&idx, b);
-    return (IndexType) idx;
-  }
-
-#else  // Compiler is neither GCC nor MSVC compatible
-
-#error "Compiler not supported."
-
-#endif
-
-
-#if defined(USE_SSSE3)
-  alignas(CacheLineSize) static inline const std::array<std::array<std::uint16_t, 8>, 256> lookup_indices = [](){
-    std::array<std::array<std::uint16_t, 8>, 256> v{};
-    for (int i = 0; i < 256; ++i)
-    {
-      int j = i;
-      int k = 0;
-      while(j)
+#if (USE_SSSE3 | (USE_NEON >= 8))
+alignas(CacheLineSize) static inline const
+  std::array<std::array<std::uint16_t, 8>, 256> lookup_indices = []() {
+      std::array<std::array<std::uint16_t, 8>, 256> v{};
+      for (unsigned i = 0; i < 256; ++i)
       {
-        const IndexType lsbIndex = lsb_(std::uint32_t(j));
-        j &= j - 1;
-        v[i][k] = lsbIndex;
-        ++k;
+          std::uint64_t j = i, k = 0;
+          while (j)
+              v[i][k++] = pop_lsb(j);
       }
-    }
-    return v;
-  }();
-  alignas(CacheLineSize) static inline const std::array<unsigned, 256> lookup_count = [](){
-    std::array<unsigned, 256> v;
-    for (int i = 0; i < 256; ++i)
-    {
-      int j = i;
-      int k = 0;
-      while(j)
-      {
-        j &= j - 1;
-        ++k;
-      }
-      v[i] = k;
-    }
-    return v;
+      return v;
   }();
 
-  // Find indices of nonzero numbers in an int32_t array
-  template<const IndexType InputDimensions>
-  void find_nnz(const std::int32_t* input, std::uint16_t* out, IndexType& count_out) {
-#if defined (USE_AVX512)
+// Find indices of nonzero numbers in an int32_t array
+template<const IndexType InputDimensions>
+void find_nnz(const std::int32_t* input, std::uint16_t* out, IndexType& count_out) {
+    #if defined(USE_SSSE3)
+        #if defined(USE_AVX512)
     using vec_t = __m512i;
-    #define vec_nnz(a) _mm512_cmpgt_epi32_mask(a, _mm512_setzero_si512())
-#elif defined (USE_AVX2)
+            #define vec_nnz(a) _mm512_cmpgt_epi32_mask(a, _mm512_setzero_si512())
+        #elif defined(USE_AVX2)
     using vec_t = __m256i;
-    #define vec_nnz(a) _mm256_movemask_ps(_mm256_castsi256_ps(_mm256_cmpgt_epi32(a, _mm256_setzero_si256())))
-#elif defined (USE_SSSE3)
+            #if defined(USE_VNNI) && !defined(USE_AVXVNNI)
+                #define vec_nnz(a) _mm256_cmpgt_epi32_mask(a, _mm256_setzero_si256())
+            #else
+                #define vec_nnz(a) \
+                    _mm256_movemask_ps( \
+                      _mm256_castsi256_ps(_mm256_cmpgt_epi32(a, _mm256_setzero_si256())))
+            #endif
+        #elif defined(USE_SSSE3)
     using vec_t = __m128i;
-    #define vec_nnz(a) _mm_movemask_ps(_mm_castsi128_ps(_mm_cmpgt_epi32(a, _mm_setzero_si128())))
-#endif
+            #define vec_nnz(a) \
+                _mm_movemask_ps(_mm_castsi128_ps(_mm_cmpgt_epi32(a, _mm_setzero_si128())))
+        #endif
+    using vec128_t = __m128i;
+        #define vec128_zero _mm_setzero_si128()
+        #define vec128_set_16(a) _mm_set1_epi16(a)
+        #define vec128_load(a) _mm_load_si128(a)
+        #define vec128_storeu(a, b) _mm_storeu_si128(a, b)
+        #define vec128_add(a, b) _mm_add_epi16(a, b)
+    #elif defined(USE_NEON)
+    using vec_t                        = uint32x4_t;
+    static const std::uint32_t Mask[4] = {1, 2, 4, 8};
+        #define vec_nnz(a) vaddvq_u32(vandq_u32(vtstq_u32(a, a), vld1q_u32(Mask)))
+    using vec128_t                     = uint16x8_t;
+        #define vec128_zero vdupq_n_u16(0)
+        #define vec128_set_16(a) vdupq_n_u16(a)
+        #define vec128_load(a) vld1q_u16(reinterpret_cast<const std::uint16_t*>(a))
+        #define vec128_storeu(a, b) vst1q_u16(reinterpret_cast<std::uint16_t*>(a), b)
+        #define vec128_add(a, b) vaddq_u16(a, b)
+    #endif
     constexpr IndexType InputSimdWidth = sizeof(vec_t) / sizeof(std::int32_t);
     // Inputs are processed InputSimdWidth at a time and outputs are processed 8 at a time so we process in chunks of max(InputSimdWidth, 8)
-    constexpr IndexType ChunkSize = std::max<IndexType>(InputSimdWidth, 8);
-    constexpr IndexType NumChunks = InputDimensions / ChunkSize;
-    constexpr IndexType InputsPerChunk = ChunkSize / InputSimdWidth;
+    constexpr IndexType ChunkSize       = std::max<IndexType>(InputSimdWidth, 8);
+    constexpr IndexType NumChunks       = InputDimensions / ChunkSize;
+    constexpr IndexType InputsPerChunk  = ChunkSize / InputSimdWidth;
     constexpr IndexType OutputsPerChunk = ChunkSize / 8;
 
-    const auto inputVector = reinterpret_cast<const vec_t*>(input);
-    IndexType count = 0;
-    __m128i base = _mm_set1_epi16(0);
-    __m128i increment = _mm_set1_epi16(8);
+    const auto     inputVector = reinterpret_cast<const vec_t*>(input);
+    IndexType      count       = 0;
+    vec128_t       base        = vec128_zero;
+    const vec128_t increment   = vec128_set_16(8);
     for (IndexType i = 0; i < NumChunks; ++i)
     {
-      // bitmask of nonzero values in this chunk
-      unsigned nnz = 0;
-      for (IndexType j = 0; j < InputsPerChunk; ++j)
-      {
-        const vec_t inputChunk = inputVector[i * InputsPerChunk + j];
-        nnz |= (unsigned)vec_nnz(inputChunk) << (j * InputSimdWidth);
-      }
-      for (IndexType j = 0; j < OutputsPerChunk; ++j)
-      {
-        const auto lookup = (nnz >> (j * 8)) & 0xFF;
-        const auto offsets = _mm_loadu_si128(reinterpret_cast<const __m128i*>(&lookup_indices[lookup]));
-        _mm_storeu_si128(reinterpret_cast<__m128i*>(out + count), _mm_add_epi16(base, offsets));
-        count += lookup_count[lookup];
-        base = _mm_add_epi16(base, increment);
-      }
+        // bitmask of nonzero values in this chunk
+        unsigned nnz = 0;
+        for (IndexType j = 0; j < InputsPerChunk; ++j)
+        {
+            const vec_t inputChunk = inputVector[i * InputsPerChunk + j];
+            nnz |= unsigned(vec_nnz(inputChunk)) << (j * InputSimdWidth);
+        }
+        for (IndexType j = 0; j < OutputsPerChunk; ++j)
+        {
+            const auto lookup = (nnz >> (j * 8)) & 0xFF;
+            const auto offsets =
+              vec128_load(reinterpret_cast<const vec128_t*>(&lookup_indices[lookup]));
+            vec128_storeu(reinterpret_cast<vec128_t*>(out + count), vec128_add(base, offsets));
+            count += popcount(lookup);
+            base = vec128_add(base, increment);
+        }
     }
     count_out = count;
-  }
-# undef vec_nnz
+}
+    #undef vec_nnz
+    #undef vec128_zero
+    #undef vec128_set_16
+    #undef vec128_load
+    #undef vec128_storeu
+    #undef vec128_add
 #endif
 
-  // Sparse input implementation
-  template <IndexType InDims, IndexType OutDims>
-  class AffineTransformSparseInput {
+// Sparse input implementation
+template<IndexType InDims, IndexType OutDims>
+class AffineTransformSparseInput {
    public:
     // Input/output type
-    // Input/output type
-    using InputType = std::uint8_t;
+    using InputType  = std::uint8_t;
     using OutputType = std::int32_t;
 
     // Number of input/output dimensions
-    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType InputDimensions  = InDims;
     static constexpr IndexType OutputDimensions = OutDims;
 
-    static_assert(OutputDimensions % 16 == 0, "Only implemented for OutputDimensions divisible by 16.");
+    static_assert(OutputDimensions % 16 == 0,
+                  "Only implemented for OutputDimensions divisible by 16.");
 
     static constexpr IndexType PaddedInputDimensions =
       ceil_to_multiple<IndexType>(InputDimensions, MaxSimdWidth);
     static constexpr IndexType PaddedOutputDimensions =
       ceil_to_multiple<IndexType>(OutputDimensions, MaxSimdWidth);
 
-#if defined (USE_SSSE3)
+#if (USE_SSSE3 | (USE_NEON >= 8))
     static constexpr IndexType ChunkSize = 4;
 #else
     static constexpr IndexType ChunkSize = 1;
@@ -167,120 +158,121 @@ namespace Stockfish::Eval::NNUE::Layers {
 
     // Hash value embedded in the evaluation file
     static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hashValue = 0xCC03DAE4u;
-      hashValue += OutputDimensions;
-      hashValue ^= prevHash >> 1;
-      hashValue ^= prevHash << 31;
-      return hashValue;
+        std::uint32_t hashValue = 0xCC03DAE4u;
+        hashValue += OutputDimensions;
+        hashValue ^= prevHash >> 1;
+        hashValue ^= prevHash << 31;
+        return hashValue;
     }
 
-    static IndexType get_weight_index_scrambled(IndexType i)
-    {
-      return
-        (i / ChunkSize) % (PaddedInputDimensions / ChunkSize) * OutputDimensions * ChunkSize +
-        i / PaddedInputDimensions * ChunkSize +
-        i % ChunkSize;
+    static constexpr IndexType get_weight_index_scrambled(IndexType i) {
+        return (i / ChunkSize) % (PaddedInputDimensions / ChunkSize) * OutputDimensions * ChunkSize
+             + i / PaddedInputDimensions * ChunkSize + i % ChunkSize;
     }
 
-    static IndexType get_weight_index(IndexType i)
-    {
-#if defined (USE_SSSE3)
-      return get_weight_index_scrambled(i);
+    static constexpr IndexType get_weight_index(IndexType i) {
+#if (USE_SSSE3 | (USE_NEON >= 8))
+        return get_weight_index_scrambled(i);
 #else
-      return i;
+        return i;
 #endif
     }
 
     // Read network parameters
     bool read_parameters(std::istream& stream) {
-      read_little_endian<BiasType>(stream, biases, OutputDimensions);
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
+        read_little_endian<BiasType>(stream, biases, OutputDimensions);
+        for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+            weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
 
-      return !stream.fail();
+        return !stream.fail();
     }
 
     // Write network parameters
     bool write_parameters(std::ostream& stream) const {
-      write_little_endian<BiasType>(stream, biases, OutputDimensions);
+        write_little_endian<BiasType>(stream, biases, OutputDimensions);
 
-      for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
-        write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
+        for (IndexType i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+            write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
 
-      return !stream.fail();
+        return !stream.fail();
     }
     // Forward propagation
-    const OutputType* propagate(
-        const InputType* input, OutputType* output) const {
+    void propagate(const InputType* input, OutputType* output) const {
 
-#if defined (USE_SSSE3)
-#if defined (USE_AVX512)
-      using vec_t = __m512i;
-      #define vec_setzero _mm512_setzero_si512
-      #define vec_set_32 _mm512_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m512_add_dpbusd_epi32
-#elif defined (USE_AVX2)
-      using vec_t = __m256i;
-      #define vec_setzero _mm256_setzero_si256
-      #define vec_set_32 _mm256_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
-#elif defined (USE_SSSE3)
-      using vec_t = __m128i;
-      #define vec_setzero _mm_setzero_si128
-      #define vec_set_32 _mm_set1_epi32
-      #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
-#endif
-      static constexpr IndexType OutputSimdWidth = sizeof(vec_t) / sizeof(OutputType);
+#if (USE_SSSE3 | (USE_NEON >= 8))
+    #if defined(USE_AVX512)
+        using invec_t  = __m512i;
+        using outvec_t = __m512i;
+        #define vec_set_32 _mm512_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m512_add_dpbusd_epi32
+    #elif defined(USE_AVX2)
+        using invec_t  = __m256i;
+        using outvec_t = __m256i;
+        #define vec_set_32 _mm256_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
+    #elif defined(USE_SSSE3)
+        using invec_t  = __m128i;
+        using outvec_t = __m128i;
+        #define vec_set_32 _mm_set1_epi32
+        #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
+    #elif defined(USE_NEON_DOTPROD)
+        using invec_t  = int8x16_t;
+        using outvec_t = int32x4_t;
+        #define vec_set_32(a) vreinterpretq_s8_u32(vdupq_n_u32(a))
+        #define vec_add_dpbusd_32 Simd::dotprod_m128_add_dpbusd_epi32
+    #elif defined(USE_NEON)
+        using invec_t  = int8x16_t;
+        using outvec_t = int32x4_t;
+        #define vec_set_32(a) vreinterpretq_s8_u32(vdupq_n_u32(a))
+        #define vec_add_dpbusd_32 Simd::neon_m128_add_dpbusd_epi32
+    #endif
+        static constexpr IndexType OutputSimdWidth = sizeof(outvec_t) / sizeof(OutputType);
 
-      constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / ChunkSize;
-      constexpr IndexType NumRegs = OutputDimensions / OutputSimdWidth;
-      std::uint16_t nnz[NumChunks];
-      IndexType count;
+        constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / ChunkSize;
+        constexpr IndexType NumRegs   = OutputDimensions / OutputSimdWidth;
+        std::uint16_t       nnz[NumChunks];
+        IndexType           count;
 
-      const auto input32 = reinterpret_cast<const std::int32_t*>(input);
+        const auto input32 = reinterpret_cast<const std::int32_t*>(input);
 
-      // Find indices of nonzero 32bit blocks
-      find_nnz<NumChunks>(input32, nnz, count);
+        // Find indices of nonzero 32-bit blocks
+        find_nnz<NumChunks>(input32, nnz, count);
 
-      const vec_t* biasvec = reinterpret_cast<const vec_t*>(biases);
-      vec_t acc[NumRegs];
-      for (IndexType k = 0; k < NumRegs; ++k)
-        acc[k] = biasvec[k];
-
-      for (IndexType j = 0; j < count; ++j)
-      {
-        const auto i = nnz[j];
-        const vec_t in = vec_set_32(input32[i]);
-        const auto col = reinterpret_cast<const vec_t*>(&weights[i * OutputDimensions * ChunkSize]);
+        const outvec_t* biasvec = reinterpret_cast<const outvec_t*>(biases);
+        outvec_t        acc[NumRegs];
         for (IndexType k = 0; k < NumRegs; ++k)
-          vec_add_dpbusd_32(acc[k], in, col[k]);
-      }
+            acc[k] = biasvec[k];
 
-      vec_t* outptr = reinterpret_cast<vec_t*>(output);
-      for (IndexType k = 0; k < NumRegs; ++k)
-        outptr[k] = acc[k];
-# undef vec_setzero
-# undef vec_set_32
-# undef vec_add_dpbusd_32
+        for (IndexType j = 0; j < count; ++j)
+        {
+            const auto    i  = nnz[j];
+            const invec_t in = vec_set_32(input32[i]);
+            const auto    col =
+              reinterpret_cast<const invec_t*>(&weights[i * OutputDimensions * ChunkSize]);
+            for (IndexType k = 0; k < NumRegs; ++k)
+                vec_add_dpbusd_32(acc[k], in, col[k]);
+        }
+
+        outvec_t* outptr = reinterpret_cast<outvec_t*>(output);
+        for (IndexType k = 0; k < NumRegs; ++k)
+            outptr[k] = acc[k];
+    #undef vec_set_32
+    #undef vec_add_dpbusd_32
 #else
-      // Use dense implementation for the other architectures.
-      affine_transform_non_ssse3<
-        InputDimensions,
-        PaddedInputDimensions,
-        OutputDimensions>(output, weights, biases, input);
+        // Use dense implementation for the other architectures.
+        affine_transform_non_ssse3<InputDimensions, PaddedInputDimensions, OutputDimensions>(
+          output, weights, biases, input);
 #endif
-
-      return output;
     }
 
    private:
-    using BiasType = OutputType;
+    using BiasType   = OutputType;
     using WeightType = std::int8_t;
 
     alignas(CacheLineSize) BiasType biases[OutputDimensions];
     alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
-  };
+};
 
 }  // namespace Stockfish::Eval::NNUE::Layers
 
-#endif // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_SPARSE_INPUT_H_INCLUDED
+#endif  // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_SPARSE_INPUT_H_INCLUDED

src/nnue/layers/clipped_relu.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,160 +21,148 @@
 #ifndef NNUE_LAYERS_CLIPPED_RELU_H_INCLUDED
 #define NNUE_LAYERS_CLIPPED_RELU_H_INCLUDED
 
+#include <algorithm>
+#include <cstdint>
+#include <iosfwd>
+
 #include "../nnue_common.h"
 
 namespace Stockfish::Eval::NNUE::Layers {
 
-  // Clipped ReLU
-  template <IndexType InDims>
-  class ClippedReLU {
+// Clipped ReLU
+template<IndexType InDims>
+class ClippedReLU {
    public:
     // Input/output type
-    using InputType = std::int32_t;
+    using InputType  = std::int32_t;
     using OutputType = std::uint8_t;
 
     // Number of input/output dimensions
-    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType InputDimensions  = InDims;
     static constexpr IndexType OutputDimensions = InputDimensions;
     static constexpr IndexType PaddedOutputDimensions =
-        ceil_to_multiple<IndexType>(OutputDimensions, 32);
+      ceil_to_multiple<IndexType>(OutputDimensions, 32);
 
     using OutputBuffer = OutputType[PaddedOutputDimensions];
 
     // Hash value embedded in the evaluation file
     static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hashValue = 0x538D24C7u;
-      hashValue += prevHash;
-      return hashValue;
+        std::uint32_t hashValue = 0x538D24C7u;
+        hashValue += prevHash;
+        return hashValue;
     }
 
     // Read network parameters
-    bool read_parameters(std::istream&) {
-      return true;
-    }
+    bool read_parameters(std::istream&) { return true; }
 
     // Write network parameters
-    bool write_parameters(std::ostream&) const {
-      return true;
-    }
+    bool write_parameters(std::ostream&) const { return true; }
 
     // Forward propagation
-    const OutputType* propagate(
-        const InputType* input, OutputType* output) const {
+    void propagate(const InputType* input, OutputType* output) const {
 
-  #if defined(USE_AVX2)
-      if constexpr (InputDimensions % SimdWidth == 0) {
+#if defined(USE_AVX2)
+        if constexpr (InputDimensions % SimdWidth == 0)
+        {
+            constexpr IndexType NumChunks = InputDimensions / SimdWidth;
+            const __m256i       Zero      = _mm256_setzero_si256();
+            const __m256i       Offsets   = _mm256_set_epi32(7, 3, 6, 2, 5, 1, 4, 0);
+            const auto          in        = reinterpret_cast<const __m256i*>(input);
+            const auto          out       = reinterpret_cast<__m256i*>(output);
+            for (IndexType i = 0; i < NumChunks; ++i)
+            {
+                const __m256i words0 =
+                  _mm256_srai_epi16(_mm256_packs_epi32(_mm256_load_si256(&in[i * 4 + 0]),
+                                                       _mm256_load_si256(&in[i * 4 + 1])),
+                                    WeightScaleBits);
+                const __m256i words1 =
+                  _mm256_srai_epi16(_mm256_packs_epi32(_mm256_load_si256(&in[i * 4 + 2]),
+                                                       _mm256_load_si256(&in[i * 4 + 3])),
+                                    WeightScaleBits);
+                _mm256_store_si256(
+                  &out[i], _mm256_permutevar8x32_epi32(
+                             _mm256_max_epi8(_mm256_packs_epi16(words0, words1), Zero), Offsets));
+            }
+        }
+        else
+        {
+            constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
+            const __m128i       Zero      = _mm_setzero_si128();
+            const auto          in        = reinterpret_cast<const __m128i*>(input);
+            const auto          out       = reinterpret_cast<__m128i*>(output);
+            for (IndexType i = 0; i < NumChunks; ++i)
+            {
+                const __m128i words0 = _mm_srai_epi16(
+                  _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 0]), _mm_load_si128(&in[i * 4 + 1])),
+                  WeightScaleBits);
+                const __m128i words1 = _mm_srai_epi16(
+                  _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 2]), _mm_load_si128(&in[i * 4 + 3])),
+                  WeightScaleBits);
+                const __m128i packedbytes = _mm_packs_epi16(words0, words1);
+                _mm_store_si128(&out[i], _mm_max_epi8(packedbytes, Zero));
+            }
+        }
+        constexpr IndexType Start = InputDimensions % SimdWidth == 0
+                                    ? InputDimensions / SimdWidth * SimdWidth
+                                    : InputDimensions / (SimdWidth / 2) * (SimdWidth / 2);
+
+#elif defined(USE_SSE2)
         constexpr IndexType NumChunks = InputDimensions / SimdWidth;
-        const __m256i Zero = _mm256_setzero_si256();
-        const __m256i Offsets = _mm256_set_epi32(7, 3, 6, 2, 5, 1, 4, 0);
-        const auto in = reinterpret_cast<const __m256i*>(input);
-        const auto out = reinterpret_cast<__m256i*>(output);
-        for (IndexType i = 0; i < NumChunks; ++i) {
-          const __m256i words0 = _mm256_srai_epi16(_mm256_packs_epi32(
-              _mm256_load_si256(&in[i * 4 + 0]),
-              _mm256_load_si256(&in[i * 4 + 1])), WeightScaleBits);
-          const __m256i words1 = _mm256_srai_epi16(_mm256_packs_epi32(
-              _mm256_load_si256(&in[i * 4 + 2]),
-              _mm256_load_si256(&in[i * 4 + 3])), WeightScaleBits);
-          _mm256_store_si256(&out[i], _mm256_permutevar8x32_epi32(_mm256_max_epi8(
-              _mm256_packs_epi16(words0, words1), Zero), Offsets));
-        }
-      } else {
-        constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
+
+    #ifdef USE_SSE41
         const __m128i Zero = _mm_setzero_si128();
-        const auto in = reinterpret_cast<const __m128i*>(input);
+    #else
+        const __m128i k0x80s = _mm_set1_epi8(-128);
+    #endif
+
+        const auto in  = reinterpret_cast<const __m128i*>(input);
         const auto out = reinterpret_cast<__m128i*>(output);
-        for (IndexType i = 0; i < NumChunks; ++i) {
-          const __m128i words0 = _mm_srai_epi16(_mm_packs_epi32(
-              _mm_load_si128(&in[i * 4 + 0]),
-              _mm_load_si128(&in[i * 4 + 1])), WeightScaleBits);
-          const __m128i words1 = _mm_srai_epi16(_mm_packs_epi32(
-              _mm_load_si128(&in[i * 4 + 2]),
-              _mm_load_si128(&in[i * 4 + 3])), WeightScaleBits);
-          const __m128i packedbytes = _mm_packs_epi16(words0, words1);
-          _mm_store_si128(&out[i], _mm_max_epi8(packedbytes, Zero));
+        for (IndexType i = 0; i < NumChunks; ++i)
+        {
+            const __m128i words0 = _mm_srai_epi16(
+              _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 0]), _mm_load_si128(&in[i * 4 + 1])),
+              WeightScaleBits);
+            const __m128i words1 = _mm_srai_epi16(
+              _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 2]), _mm_load_si128(&in[i * 4 + 3])),
+              WeightScaleBits);
+            const __m128i packedbytes = _mm_packs_epi16(words0, words1);
+            _mm_store_si128(&out[i],
+
+    #ifdef USE_SSE41
+                            _mm_max_epi8(packedbytes, Zero)
+    #else
+                            _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
+    #endif
+
+            );
         }
-      }
-      constexpr IndexType Start =
-        InputDimensions % SimdWidth == 0
-        ? InputDimensions / SimdWidth * SimdWidth
-        : InputDimensions / (SimdWidth / 2) * (SimdWidth / 2);
+        constexpr IndexType Start = NumChunks * SimdWidth;
 
-  #elif defined(USE_SSE2)
-      constexpr IndexType NumChunks = InputDimensions / SimdWidth;
+#elif defined(USE_NEON)
+        constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
+        const int8x8_t      Zero      = {0};
+        const auto          in        = reinterpret_cast<const int32x4_t*>(input);
+        const auto          out       = reinterpret_cast<int8x8_t*>(output);
+        for (IndexType i = 0; i < NumChunks; ++i)
+        {
+            int16x8_t  shifted;
+            const auto pack = reinterpret_cast<int16x4_t*>(&shifted);
+            pack[0]         = vqshrn_n_s32(in[i * 2 + 0], WeightScaleBits);
+            pack[1]         = vqshrn_n_s32(in[i * 2 + 1], WeightScaleBits);
+            out[i]          = vmax_s8(vqmovn_s16(shifted), Zero);
+        }
+        constexpr IndexType Start = NumChunks * (SimdWidth / 2);
+#else
+        constexpr IndexType Start = 0;
+#endif
 
-  #ifdef USE_SSE41
-      const __m128i Zero = _mm_setzero_si128();
-  #else
-      const __m128i k0x80s = _mm_set1_epi8(-128);
-  #endif
-
-      const auto in = reinterpret_cast<const __m128i*>(input);
-      const auto out = reinterpret_cast<__m128i*>(output);
-      for (IndexType i = 0; i < NumChunks; ++i) {
-        const __m128i words0 = _mm_srai_epi16(_mm_packs_epi32(
-            _mm_load_si128(&in[i * 4 + 0]),
-            _mm_load_si128(&in[i * 4 + 1])), WeightScaleBits);
-        const __m128i words1 = _mm_srai_epi16(_mm_packs_epi32(
-            _mm_load_si128(&in[i * 4 + 2]),
-            _mm_load_si128(&in[i * 4 + 3])), WeightScaleBits);
-        const __m128i packedbytes = _mm_packs_epi16(words0, words1);
-        _mm_store_si128(&out[i],
-
-  #ifdef USE_SSE41
-          _mm_max_epi8(packedbytes, Zero)
-  #else
-          _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
-  #endif
-
-        );
-      }
-      constexpr IndexType Start = NumChunks * SimdWidth;
-
-  #elif defined(USE_MMX)
-      constexpr IndexType NumChunks = InputDimensions / SimdWidth;
-      const __m64 k0x80s = _mm_set1_pi8(-128);
-      const auto in = reinterpret_cast<const __m64*>(input);
-      const auto out = reinterpret_cast<__m64*>(output);
-      for (IndexType i = 0; i < NumChunks; ++i) {
-        const __m64 words0 = _mm_srai_pi16(
-            _mm_packs_pi32(in[i * 4 + 0], in[i * 4 + 1]),
-            WeightScaleBits);
-        const __m64 words1 = _mm_srai_pi16(
-            _mm_packs_pi32(in[i * 4 + 2], in[i * 4 + 3]),
-            WeightScaleBits);
-        const __m64 packedbytes = _mm_packs_pi16(words0, words1);
-        out[i] = _mm_subs_pi8(_mm_adds_pi8(packedbytes, k0x80s), k0x80s);
-      }
-      _mm_empty();
-      constexpr IndexType Start = NumChunks * SimdWidth;
-
-  #elif defined(USE_NEON)
-      constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
-      const int8x8_t Zero = {0};
-      const auto in = reinterpret_cast<const int32x4_t*>(input);
-      const auto out = reinterpret_cast<int8x8_t*>(output);
-      for (IndexType i = 0; i < NumChunks; ++i) {
-        int16x8_t shifted;
-        const auto pack = reinterpret_cast<int16x4_t*>(&shifted);
-        pack[0] = vqshrn_n_s32(in[i * 2 + 0], WeightScaleBits);
-        pack[1] = vqshrn_n_s32(in[i * 2 + 1], WeightScaleBits);
-        out[i] = vmax_s8(vqmovn_s16(shifted), Zero);
-      }
-      constexpr IndexType Start = NumChunks * (SimdWidth / 2);
-  #else
-      constexpr IndexType Start = 0;
-  #endif
-
-      for (IndexType i = Start; i < InputDimensions; ++i) {
-        output[i] = static_cast<OutputType>(
-            std::max(0, std::min(127, input[i] >> WeightScaleBits)));
-      }
-
-      return output;
+        for (IndexType i = Start; i < InputDimensions; ++i)
+        {
+            output[i] = static_cast<OutputType>(std::clamp(input[i] >> WeightScaleBits, 0, 127));
+        }
     }
-  };
+};
 
 }  // namespace Stockfish::Eval::NNUE::Layers
 
-#endif // NNUE_LAYERS_CLIPPED_RELU_H_INCLUDED
+#endif  // NNUE_LAYERS_CLIPPED_RELU_H_INCLUDED

src/nnue/layers/simd.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,48 +20,30 @@
 #define STOCKFISH_SIMD_H_INCLUDED
 
 #if defined(USE_AVX2)
-# include <immintrin.h>
+    #include <immintrin.h>
 
 #elif defined(USE_SSE41)
-# include <smmintrin.h>
+    #include <smmintrin.h>
 
 #elif defined(USE_SSSE3)
-# include <tmmintrin.h>
+    #include <tmmintrin.h>
 
 #elif defined(USE_SSE2)
-# include <emmintrin.h>
-
-#elif defined(USE_MMX)
-# include <mmintrin.h>
+    #include <emmintrin.h>
 
 #elif defined(USE_NEON)
-# include <arm_neon.h>
-#endif
-
-// The inline asm is only safe for GCC, where it is necessary to get good codegen.
-// See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101693
-// Clang does fine without it.
-// Play around here: https://godbolt.org/z/7EWqrYq51
-#if (defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER))
-#define USE_INLINE_ASM
-#endif
-
-// Use either the AVX512 or AVX-VNNI version of the VNNI instructions.
-#if defined(USE_AVXVNNI)
-#define VNNI_PREFIX "%{vex%} "
-#else
-#define VNNI_PREFIX ""
+    #include <arm_neon.h>
 #endif
 
 namespace Stockfish::Simd {
 
-#if defined (USE_AVX512)
+#if defined(USE_AVX512)
 
-    [[maybe_unused]] static int m512_hadd(__m512i sum, int bias) {
-      return _mm512_reduce_add_epi32(sum) + bias;
-    }
+[[maybe_unused]] static int m512_hadd(__m512i sum, int bias) {
+    return _mm512_reduce_add_epi32(sum) + bias;
+}
 
-    /*
+/*
       Parameters:
         sum0 = [zmm0.i128[0], zmm0.i128[1], zmm0.i128[2], zmm0.i128[3]]
         sum1 = [zmm1.i128[0], zmm1.i128[1], zmm1.i128[2], zmm1.i128[3]]
@@ -76,328 +58,110 @@ namespace Stockfish::Simd {
           reduce_add_epi32(zmm0.i128[3]), reduce_add_epi32(zmm1.i128[3]), reduce_add_epi32(zmm2.i128[3]), reduce_add_epi32(zmm3.i128[3])
         ]
     */
-    [[maybe_unused]] static __m512i m512_hadd128x16_interleave(
-        __m512i sum0, __m512i sum1, __m512i sum2, __m512i sum3) {
+[[maybe_unused]] static __m512i
+m512_hadd128x16_interleave(__m512i sum0, __m512i sum1, __m512i sum2, __m512i sum3) {
 
-      __m512i sum01a = _mm512_unpacklo_epi32(sum0, sum1);
-      __m512i sum01b = _mm512_unpackhi_epi32(sum0, sum1);
+    __m512i sum01a = _mm512_unpacklo_epi32(sum0, sum1);
+    __m512i sum01b = _mm512_unpackhi_epi32(sum0, sum1);
 
-      __m512i sum23a = _mm512_unpacklo_epi32(sum2, sum3);
-      __m512i sum23b = _mm512_unpackhi_epi32(sum2, sum3);
+    __m512i sum23a = _mm512_unpacklo_epi32(sum2, sum3);
+    __m512i sum23b = _mm512_unpackhi_epi32(sum2, sum3);
 
-      __m512i sum01 = _mm512_add_epi32(sum01a, sum01b);
-      __m512i sum23 = _mm512_add_epi32(sum23a, sum23b);
+    __m512i sum01 = _mm512_add_epi32(sum01a, sum01b);
+    __m512i sum23 = _mm512_add_epi32(sum23a, sum23b);
 
-      __m512i sum0123a = _mm512_unpacklo_epi64(sum01, sum23);
-      __m512i sum0123b = _mm512_unpackhi_epi64(sum01, sum23);
-
-      return _mm512_add_epi32(sum0123a, sum0123b);
-    }
-
-    [[maybe_unused]] static __m128i m512_haddx4(
-        __m512i sum0, __m512i sum1, __m512i sum2, __m512i sum3,
-        __m128i bias) {
-
-      __m512i sum = m512_hadd128x16_interleave(sum0, sum1, sum2, sum3);
-
-      __m256i sum256lo = _mm512_castsi512_si256(sum);
-      __m256i sum256hi = _mm512_extracti64x4_epi64(sum, 1);
-
-      sum256lo = _mm256_add_epi32(sum256lo, sum256hi);
-
-      __m128i sum128lo = _mm256_castsi256_si128(sum256lo);
-      __m128i sum128hi = _mm256_extracti128_si256(sum256lo, 1);
-
-      return _mm_add_epi32(_mm_add_epi32(sum128lo, sum128hi), bias);
-    }
-
-    [[maybe_unused]] static void m512_add_dpbusd_epi32(
-        __m512i& acc,
-        __m512i a,
-        __m512i b) {
-
-# if defined (USE_VNNI)
-#   if defined (USE_INLINE_ASM)
-      asm(
-        "vpdpbusd %[b], %[a], %[acc]\n\t"
-        : [acc]"+v"(acc)
-        : [a]"v"(a), [b]"vm"(b)
-      );
-#   else
-      acc = _mm512_dpbusd_epi32(acc, a, b);
-#   endif
-# else
-#   if defined (USE_INLINE_ASM)
-      __m512i tmp = _mm512_maddubs_epi16(a, b);
-      asm(
-          "vpmaddwd    %[tmp], %[ones], %[tmp]\n\t"
-          "vpaddd      %[acc], %[tmp], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
-          : [ones]"v"(_mm512_set1_epi16(1))
-      );
-#   else
-      __m512i product0 = _mm512_maddubs_epi16(a, b);
-      product0 = _mm512_madd_epi16(product0, _mm512_set1_epi16(1));
-      acc = _mm512_add_epi32(acc, product0);
-#   endif
-# endif
-    }
-
-    [[maybe_unused]] static void m512_add_dpbusd_epi32x2(
-        __m512i& acc,
-        __m512i a0, __m512i b0,
-        __m512i a1, __m512i b1) {
-
-# if defined (USE_VNNI)
-#   if defined (USE_INLINE_ASM)
-      asm(
-        "vpdpbusd %[b0], %[a0], %[acc]\n\t"
-        "vpdpbusd %[b1], %[a1], %[acc]\n\t"
-        : [acc]"+&v"(acc)
-        : [a0]"v"(a0), [b0]"vm"(b0), [a1]"v"(a1), [b1]"vm"(b1)
-      );
-#   else
-      acc = _mm512_dpbusd_epi32(acc, a0, b0);
-      acc = _mm512_dpbusd_epi32(acc, a1, b1);
-#   endif
-# else
-#   if defined (USE_INLINE_ASM)
-      __m512i tmp0 = _mm512_maddubs_epi16(a0, b0);
-      __m512i tmp1 = _mm512_maddubs_epi16(a1, b1);
-      asm(
-          "vpmaddwd    %[tmp0], %[ones], %[tmp0]\n\t"
-          "vpmaddwd    %[tmp1], %[ones], %[tmp1]\n\t"
-          "vpaddd      %[tmp0], %[tmp1], %[tmp0]\n\t"
-          "vpaddd      %[acc], %[tmp0], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0), [tmp1]"+&v"(tmp1)
-          : [ones]"v"(_mm512_set1_epi16(1))
-      );
-#   else
-      __m512i product0 = _mm512_maddubs_epi16(a0, b0);
-      __m512i product1 = _mm512_maddubs_epi16(a1, b1);
-      product0 = _mm512_madd_epi16(product0, _mm512_set1_epi16(1));
-      product1 = _mm512_madd_epi16(product1, _mm512_set1_epi16(1));
-      acc = _mm512_add_epi32(acc, _mm512_add_epi32(product0, product1));
-#   endif
-# endif
-    }
-
-#endif
-
-#if defined (USE_AVX2)
-
-    [[maybe_unused]] static int m256_hadd(__m256i sum, int bias) {
-      __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
-      sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
-      sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
-      return _mm_cvtsi128_si32(sum128) + bias;
-    }
-
-    [[maybe_unused]] static __m128i m256_haddx4(
-        __m256i sum0, __m256i sum1, __m256i sum2, __m256i sum3,
-        __m128i bias) {
-
-      sum0 = _mm256_hadd_epi32(sum0, sum1);
-      sum2 = _mm256_hadd_epi32(sum2, sum3);
-
-      sum0 = _mm256_hadd_epi32(sum0, sum2);
-
-      __m128i sum128lo = _mm256_castsi256_si128(sum0);
-      __m128i sum128hi = _mm256_extracti128_si256(sum0, 1);
-
-      return _mm_add_epi32(_mm_add_epi32(sum128lo, sum128hi), bias);
-    }
-
-    [[maybe_unused]] static void m256_add_dpbusd_epi32(
-        __m256i& acc,
-        __m256i a,
-        __m256i b) {
-
-# if defined (USE_VNNI)
-#   if defined (USE_INLINE_ASM)
-      asm(
-        VNNI_PREFIX "vpdpbusd %[b], %[a], %[acc]\n\t"
-        : [acc]"+v"(acc)
-        : [a]"v"(a), [b]"vm"(b)
-      );
-#   else
-      acc = _mm256_dpbusd_epi32(acc, a, b);
-#   endif
-# else
-#   if defined (USE_INLINE_ASM)
-      __m256i tmp = _mm256_maddubs_epi16(a, b);
-      asm(
-          "vpmaddwd    %[tmp], %[ones], %[tmp]\n\t"
-          "vpaddd      %[acc], %[tmp], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
-          : [ones]"v"(_mm256_set1_epi16(1))
-      );
-#   else
-      __m256i product0 = _mm256_maddubs_epi16(a, b);
-      product0 = _mm256_madd_epi16(product0, _mm256_set1_epi16(1));
-      acc = _mm256_add_epi32(acc, product0);
-#   endif
-# endif
-    }
-
-    [[maybe_unused]] static void m256_add_dpbusd_epi32x2(
-        __m256i& acc,
-        __m256i a0, __m256i b0,
-        __m256i a1, __m256i b1) {
-
-# if defined (USE_VNNI)
-#   if defined (USE_INLINE_ASM)
-      asm(
-        VNNI_PREFIX "vpdpbusd %[b0], %[a0], %[acc]\n\t"
-        VNNI_PREFIX "vpdpbusd %[b1], %[a1], %[acc]\n\t"
-        : [acc]"+&v"(acc)
-        : [a0]"v"(a0), [b0]"vm"(b0), [a1]"v"(a1), [b1]"vm"(b1)
-      );
-#   else
-      acc = _mm256_dpbusd_epi32(acc, a0, b0);
-      acc = _mm256_dpbusd_epi32(acc, a1, b1);
-#   endif
-# else
-#   if defined (USE_INLINE_ASM)
-      __m256i tmp0 = _mm256_maddubs_epi16(a0, b0);
-      __m256i tmp1 = _mm256_maddubs_epi16(a1, b1);
-      asm(
-          "vpmaddwd    %[tmp0], %[ones], %[tmp0]\n\t"
-          "vpmaddwd    %[tmp1], %[ones], %[tmp1]\n\t"
-          "vpaddd      %[tmp0], %[tmp1], %[tmp0]\n\t"
-          "vpaddd      %[acc], %[tmp0], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0), [tmp1]"+&v"(tmp1)
-          : [ones]"v"(_mm256_set1_epi16(1))
-      );
-#   else
-      __m256i product0 = _mm256_maddubs_epi16(a0, b0);
-      __m256i product1 = _mm256_maddubs_epi16(a1, b1);
-      product0 = _mm256_madd_epi16(product0, _mm256_set1_epi16(1));
-      product1 = _mm256_madd_epi16(product1, _mm256_set1_epi16(1));
-      acc = _mm256_add_epi32(acc, _mm256_add_epi32(product0, product1));
-#   endif
-# endif
-    }
-
-#endif
-
-#if defined (USE_SSSE3)
-
-    [[maybe_unused]] static int m128_hadd(__m128i sum, int bias) {
-      sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
-      sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
-      return _mm_cvtsi128_si32(sum) + bias;
-    }
-
-    [[maybe_unused]] static __m128i m128_haddx4(
-        __m128i sum0, __m128i sum1, __m128i sum2, __m128i sum3,
-        __m128i bias) {
-
-      sum0 = _mm_hadd_epi32(sum0, sum1);
-      sum2 = _mm_hadd_epi32(sum2, sum3);
-      sum0 = _mm_hadd_epi32(sum0, sum2);
-      return _mm_add_epi32(sum0, bias);
-    }
-
-    [[maybe_unused]] static void m128_add_dpbusd_epi32(
-        __m128i& acc,
-        __m128i a,
-        __m128i b) {
-
-#   if defined (USE_INLINE_ASM)
-      __m128i tmp = _mm_maddubs_epi16(a, b);
-      asm(
-          "pmaddwd    %[ones], %[tmp]\n\t"
-          "paddd      %[tmp], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
-          : [ones]"v"(_mm_set1_epi16(1))
-      );
-#   else
-      __m128i product0 = _mm_maddubs_epi16(a, b);
-      product0 = _mm_madd_epi16(product0, _mm_set1_epi16(1));
-      acc = _mm_add_epi32(acc, product0);
-#   endif
-    }
-
-    [[maybe_unused]] static void m128_add_dpbusd_epi32x2(
-        __m128i& acc,
-        __m128i a0, __m128i b0,
-        __m128i a1, __m128i b1) {
-
-#   if defined (USE_INLINE_ASM)
-      __m128i tmp0 = _mm_maddubs_epi16(a0, b0);
-      __m128i tmp1 = _mm_maddubs_epi16(a1, b1);
-      asm(
-          "pmaddwd    %[ones], %[tmp0]\n\t"
-          "pmaddwd    %[ones], %[tmp1]\n\t"
-          "paddd      %[tmp1], %[tmp0]\n\t"
-          "paddd      %[tmp0], %[acc]\n\t"
-          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0), [tmp1]"+&v"(tmp1)
-          : [ones]"v"(_mm_set1_epi16(1))
-      );
-#   else
-      __m128i product0 = _mm_maddubs_epi16(a0, b0);
-      __m128i product1 = _mm_maddubs_epi16(a1, b1);
-      product0 = _mm_madd_epi16(product0, _mm_set1_epi16(1));
-      product1 = _mm_madd_epi16(product1, _mm_set1_epi16(1));
-      acc = _mm_add_epi32(acc, _mm_add_epi32(product0, product1));
-#   endif
-    }
-
-#endif
-
-#if defined (USE_NEON_DOTPROD)
-
-    [[maybe_unused]] static void dotprod_m128_add_dpbusd_epi32x2(
-        int32x4_t& acc,
-        int8x16_t a0, int8x16_t b0,
-        int8x16_t a1, int8x16_t b1) {
-
-        acc = vdotq_s32(acc, a0, b0);
-        acc = vdotq_s32(acc, a1, b1);
-    }
-
-#endif
-
-#if defined (USE_NEON)
-
-    [[maybe_unused]] static int neon_m128_reduce_add_epi32(int32x4_t s) {
-#   if USE_NEON >= 8
-      return vaddvq_s32(s);
-#   else
-      return s[0] + s[1] + s[2] + s[3];
-#   endif
-    }
-
-    [[maybe_unused]] static int neon_m128_hadd(int32x4_t sum, int bias) {
-      return neon_m128_reduce_add_epi32(sum) + bias;
-    }
-
-    [[maybe_unused]] static int32x4_t neon_m128_haddx4(
-        int32x4_t sum0, int32x4_t sum1, int32x4_t sum2, int32x4_t sum3,
-        int32x4_t bias) {
-
-      int32x4_t hsums {
-        neon_m128_reduce_add_epi32(sum0),
-        neon_m128_reduce_add_epi32(sum1),
-        neon_m128_reduce_add_epi32(sum2),
-        neon_m128_reduce_add_epi32(sum3)
-      };
-      return vaddq_s32(hsums, bias);
-    }
-
-    [[maybe_unused]] static void neon_m128_add_dpbusd_epi32x2(
-        int32x4_t& acc,
-        int8x8_t a0, int8x8_t b0,
-        int8x8_t a1, int8x8_t b1) {
-
-      int16x8_t product = vmull_s8(a0, b0);
-      product = vmlal_s8(product, a1, b1);
-      acc = vpadalq_s16(acc, product);
-    }
-
-#endif
+    __m512i sum0123a = _mm512_unpacklo_epi64(sum01, sum23);
+    __m512i sum0123b = _mm512_unpackhi_epi64(sum01, sum23);
 
+    return _mm512_add_epi32(sum0123a, sum0123b);
 }
 
-#endif // STOCKFISH_SIMD_H_INCLUDED
+[[maybe_unused]] static void m512_add_dpbusd_epi32(__m512i& acc, __m512i a, __m512i b) {
+
+    #if defined(USE_VNNI)
+    acc = _mm512_dpbusd_epi32(acc, a, b);
+    #else
+    __m512i product0 = _mm512_maddubs_epi16(a, b);
+    product0         = _mm512_madd_epi16(product0, _mm512_set1_epi16(1));
+    acc              = _mm512_add_epi32(acc, product0);
+    #endif
+}
+
+#endif
+
+#if defined(USE_AVX2)
+
+[[maybe_unused]] static int m256_hadd(__m256i sum, int bias) {
+    __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
+    sum128         = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
+    sum128         = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
+    return _mm_cvtsi128_si32(sum128) + bias;
+}
+
+[[maybe_unused]] static void m256_add_dpbusd_epi32(__m256i& acc, __m256i a, __m256i b) {
+
+    #if defined(USE_VNNI)
+    acc = _mm256_dpbusd_epi32(acc, a, b);
+    #else
+    __m256i product0 = _mm256_maddubs_epi16(a, b);
+    product0         = _mm256_madd_epi16(product0, _mm256_set1_epi16(1));
+    acc              = _mm256_add_epi32(acc, product0);
+    #endif
+}
+
+#endif
+
+#if defined(USE_SSSE3)
+
+[[maybe_unused]] static int m128_hadd(__m128i sum, int bias) {
+    sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E));  //_MM_PERM_BADC
+    sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1));  //_MM_PERM_CDAB
+    return _mm_cvtsi128_si32(sum) + bias;
+}
+
+[[maybe_unused]] static void m128_add_dpbusd_epi32(__m128i& acc, __m128i a, __m128i b) {
+
+    __m128i product0 = _mm_maddubs_epi16(a, b);
+    product0         = _mm_madd_epi16(product0, _mm_set1_epi16(1));
+    acc              = _mm_add_epi32(acc, product0);
+}
+
+#endif
+
+#if defined(USE_NEON_DOTPROD)
+
+[[maybe_unused]] static void
+dotprod_m128_add_dpbusd_epi32(int32x4_t& acc, int8x16_t a, int8x16_t b) {
+
+    acc = vdotq_s32(acc, a, b);
+}
+#endif
+
+#if defined(USE_NEON)
+
+[[maybe_unused]] static int neon_m128_reduce_add_epi32(int32x4_t s) {
+    #if USE_NEON >= 8
+    return vaddvq_s32(s);
+    #else
+    return s[0] + s[1] + s[2] + s[3];
+    #endif
+}
+
+[[maybe_unused]] static int neon_m128_hadd(int32x4_t sum, int bias) {
+    return neon_m128_reduce_add_epi32(sum) + bias;
+}
+
+#endif
+
+#if USE_NEON >= 8
+[[maybe_unused]] static void neon_m128_add_dpbusd_epi32(int32x4_t& acc, int8x16_t a, int8x16_t b) {
+
+    int16x8_t product0 = vmull_s8(vget_low_s8(a), vget_low_s8(b));
+    int16x8_t product1 = vmull_high_s8(a, b);
+    int16x8_t sum      = vpaddq_s16(product0, product1);
+    acc                = vpadalq_s16(acc, sum);
+}
+#endif
+}
+
+#endif  // STOCKFISH_SIMD_H_INCLUDED

src/nnue/layers/sqr_clipped_relu.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,100 +21,83 @@
 #ifndef NNUE_LAYERS_SQR_CLIPPED_RELU_H_INCLUDED
 #define NNUE_LAYERS_SQR_CLIPPED_RELU_H_INCLUDED
 
+#include <algorithm>
+#include <cstdint>
+#include <iosfwd>
+
 #include "../nnue_common.h"
 
 namespace Stockfish::Eval::NNUE::Layers {
 
-  // Clipped ReLU
-  template <IndexType InDims>
-  class SqrClippedReLU {
+// Clipped ReLU
+template<IndexType InDims>
+class SqrClippedReLU {
    public:
     // Input/output type
-    using InputType = std::int32_t;
+    using InputType  = std::int32_t;
     using OutputType = std::uint8_t;
 
     // Number of input/output dimensions
-    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType InputDimensions  = InDims;
     static constexpr IndexType OutputDimensions = InputDimensions;
     static constexpr IndexType PaddedOutputDimensions =
-        ceil_to_multiple<IndexType>(OutputDimensions, 32);
+      ceil_to_multiple<IndexType>(OutputDimensions, 32);
 
     using OutputBuffer = OutputType[PaddedOutputDimensions];
 
     // Hash value embedded in the evaluation file
     static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hashValue = 0x538D24C7u;
-      hashValue += prevHash;
-      return hashValue;
+        std::uint32_t hashValue = 0x538D24C7u;
+        hashValue += prevHash;
+        return hashValue;
     }
 
     // Read network parameters
-    bool read_parameters(std::istream&) {
-      return true;
-    }
+    bool read_parameters(std::istream&) { return true; }
 
     // Write network parameters
-    bool write_parameters(std::ostream&) const {
-      return true;
-    }
+    bool write_parameters(std::ostream&) const { return true; }
 
     // Forward propagation
-    const OutputType* propagate(
-        const InputType* input, OutputType* output) const {
+    void propagate(const InputType* input, OutputType* output) const {
 
-  #if defined(USE_SSE2)
-      constexpr IndexType NumChunks = InputDimensions / 16;
+#if defined(USE_SSE2)
+        constexpr IndexType NumChunks = InputDimensions / 16;
 
-  #ifdef USE_SSE41
-      const __m128i Zero = _mm_setzero_si128();
-  #else
-      const __m128i k0x80s = _mm_set1_epi8(-128);
-  #endif
+        static_assert(WeightScaleBits == 6);
+        const auto in  = reinterpret_cast<const __m128i*>(input);
+        const auto out = reinterpret_cast<__m128i*>(output);
+        for (IndexType i = 0; i < NumChunks; ++i)
+        {
+            __m128i words0 =
+              _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 0]), _mm_load_si128(&in[i * 4 + 1]));
+            __m128i words1 =
+              _mm_packs_epi32(_mm_load_si128(&in[i * 4 + 2]), _mm_load_si128(&in[i * 4 + 3]));
 
-      static_assert(WeightScaleBits == 6);
-      const auto in = reinterpret_cast<const __m128i*>(input);
-      const auto out = reinterpret_cast<__m128i*>(output);
-      for (IndexType i = 0; i < NumChunks; ++i) {
-        __m128i words0 = _mm_packs_epi32(
-            _mm_load_si128(&in[i * 4 + 0]),
-            _mm_load_si128(&in[i * 4 + 1]));
-        __m128i words1 = _mm_packs_epi32(
-            _mm_load_si128(&in[i * 4 + 2]),
-            _mm_load_si128(&in[i * 4 + 3]));
+            // We shift by WeightScaleBits * 2 = 12 and divide by 128
+            // which is an additional shift-right of 7, meaning 19 in total.
+            // MulHi strips the lower 16 bits so we need to shift out 3 more to match.
+            words0 = _mm_srli_epi16(_mm_mulhi_epi16(words0, words0), 3);
+            words1 = _mm_srli_epi16(_mm_mulhi_epi16(words1, words1), 3);
 
-        // Not sure if
-        words0 = _mm_srli_epi16(_mm_mulhi_epi16(words0, words0), 3);
-        words1 = _mm_srli_epi16(_mm_mulhi_epi16(words1, words1), 3);
+            _mm_store_si128(&out[i], _mm_packs_epi16(words0, words1));
+        }
+        constexpr IndexType Start = NumChunks * 16;
 
-        const __m128i packedbytes = _mm_packs_epi16(words0, words1);
+#else
+        constexpr IndexType Start = 0;
+#endif
 
-        _mm_store_si128(&out[i],
-
-  #ifdef USE_SSE41
-          _mm_max_epi8(packedbytes, Zero)
-  #else
-          _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
-  #endif
-
-        );
-      }
-      constexpr IndexType Start = NumChunks * 16;
-
-  #else
-      constexpr IndexType Start = 0;
-  #endif
-
-      for (IndexType i = Start; i < InputDimensions; ++i) {
-        output[i] = static_cast<OutputType>(
-            // really should be /127 but we need to make it fast
-            // needs to be accounted for in the trainer
-            std::max(0ll, std::min(127ll, (((long long)input[i] * input[i]) >> (2 * WeightScaleBits)) / 128)));
-      }
-
-      return output;
+        for (IndexType i = Start; i < InputDimensions; ++i)
+        {
+            output[i] = static_cast<OutputType>(
+              // Really should be /127 but we need to make it fast so we right-shift
+              // by an extra 7 bits instead. Needs to be accounted for in the trainer.
+              std::min(127ll, ((long long) (input[i]) * input[i]) >> (2 * WeightScaleBits + 7)));
+        }
     }
-  };
+};
 
 }  // namespace Stockfish::Eval::NNUE::Layers
 
-#endif // NNUE_LAYERS_SQR_CLIPPED_RELU_H_INCLUDED
+#endif  // NNUE_LAYERS_SQR_CLIPPED_RELU_H_INCLUDED

src/nnue/nnue_accumulator.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,17 +21,21 @@
 #ifndef NNUE_ACCUMULATOR_H_INCLUDED
 #define NNUE_ACCUMULATOR_H_INCLUDED
 
+#include <cstdint>
+
 #include "nnue_architecture.h"
+#include "nnue_common.h"
 
 namespace Stockfish::Eval::NNUE {
 
-  // Class that holds the result of affine transformation of input features
-  struct alignas(CacheLineSize) Accumulator {
-    std::int16_t accumulation[2][TransformedFeatureDimensions];
+// Class that holds the result of affine transformation of input features
+template<IndexType Size>
+struct alignas(CacheLineSize) Accumulator {
+    std::int16_t accumulation[2][Size];
     std::int32_t psqtAccumulation[2][PSQTBuckets];
-    bool computed[2];
-  };
+    bool         computed[2];
+};
 
 }  // namespace Stockfish::Eval::NNUE
 
-#endif // NNUE_ACCUMULATOR_H_INCLUDED
+#endif  // NNUE_ACCUMULATOR_H_INCLUDED

src/nnue/nnue_architecture.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,117 +21,122 @@
 #ifndef NNUE_ARCHITECTURE_H_INCLUDED
 #define NNUE_ARCHITECTURE_H_INCLUDED
 
-#include <memory>
-
-#include "nnue_common.h"
+#include <cstdint>
+#include <cstring>
+#include <iosfwd>
 
 #include "features/half_ka_v2_hm.h"
-
-#include "layers/affine_transform_sparse_input.h"
 #include "layers/affine_transform.h"
+#include "layers/affine_transform_sparse_input.h"
 #include "layers/clipped_relu.h"
 #include "layers/sqr_clipped_relu.h"
-
-#include "../misc.h"
+#include "nnue_common.h"
 
 namespace Stockfish::Eval::NNUE {
 
 // Input features used in evaluation function
 using FeatureSet = Features::HalfKAv2_hm;
 
+enum NetSize : int {
+    Big,
+    Small
+};
+
 // Number of input feature dimensions after conversion
-constexpr IndexType TransformedFeatureDimensions = 1536;
+constexpr IndexType TransformedFeatureDimensionsBig = 2560;
+constexpr int       L2Big                           = 15;
+constexpr int       L3Big                           = 32;
+
+constexpr IndexType TransformedFeatureDimensionsSmall = 128;
+constexpr int       L2Small                           = 15;
+constexpr int       L3Small                           = 32;
+
 constexpr IndexType PSQTBuckets = 8;
 constexpr IndexType LayerStacks = 8;
 
-struct Network
-{
-  static constexpr int FC_0_OUTPUTS = 15;
-  static constexpr int FC_1_OUTPUTS = 32;
+template<IndexType L1, int L2, int L3>
+struct Network {
+    static constexpr IndexType TransformedFeatureDimensions = L1;
+    static constexpr int       FC_0_OUTPUTS                 = L2;
+    static constexpr int       FC_1_OUTPUTS                 = L3;
 
-  Layers::AffineTransformSparseInput<TransformedFeatureDimensions, FC_0_OUTPUTS + 1> fc_0;
-  Layers::SqrClippedReLU<FC_0_OUTPUTS + 1> ac_sqr_0;
-  Layers::ClippedReLU<FC_0_OUTPUTS + 1> ac_0;
-  Layers::AffineTransform<FC_0_OUTPUTS * 2, FC_1_OUTPUTS> fc_1;
-  Layers::ClippedReLU<FC_1_OUTPUTS> ac_1;
-  Layers::AffineTransform<FC_1_OUTPUTS, 1> fc_2;
+    Layers::AffineTransformSparseInput<TransformedFeatureDimensions, FC_0_OUTPUTS + 1> fc_0;
+    Layers::SqrClippedReLU<FC_0_OUTPUTS + 1>                                           ac_sqr_0;
+    Layers::ClippedReLU<FC_0_OUTPUTS + 1>                                              ac_0;
+    Layers::AffineTransform<FC_0_OUTPUTS * 2, FC_1_OUTPUTS>                            fc_1;
+    Layers::ClippedReLU<FC_1_OUTPUTS>                                                  ac_1;
+    Layers::AffineTransform<FC_1_OUTPUTS, 1>                                           fc_2;
 
-  // Hash value embedded in the evaluation file
-  static constexpr std::uint32_t get_hash_value() {
-    // input slice hash
-    std::uint32_t hashValue = 0xEC42E90Du;
-    hashValue ^= TransformedFeatureDimensions * 2;
+    // Hash value embedded in the evaluation file
+    static constexpr std::uint32_t get_hash_value() {
+        // input slice hash
+        std::uint32_t hashValue = 0xEC42E90Du;
+        hashValue ^= TransformedFeatureDimensions * 2;
 
-    hashValue = decltype(fc_0)::get_hash_value(hashValue);
-    hashValue = decltype(ac_0)::get_hash_value(hashValue);
-    hashValue = decltype(fc_1)::get_hash_value(hashValue);
-    hashValue = decltype(ac_1)::get_hash_value(hashValue);
-    hashValue = decltype(fc_2)::get_hash_value(hashValue);
+        hashValue = decltype(fc_0)::get_hash_value(hashValue);
+        hashValue = decltype(ac_0)::get_hash_value(hashValue);
+        hashValue = decltype(fc_1)::get_hash_value(hashValue);
+        hashValue = decltype(ac_1)::get_hash_value(hashValue);
+        hashValue = decltype(fc_2)::get_hash_value(hashValue);
 
-    return hashValue;
-  }
+        return hashValue;
+    }
 
-  // Read network parameters
-  bool read_parameters(std::istream& stream) {
-    return   fc_0.read_parameters(stream)
-          && ac_0.read_parameters(stream)
-          && fc_1.read_parameters(stream)
-          && ac_1.read_parameters(stream)
-          && fc_2.read_parameters(stream);
-  }
+    // Read network parameters
+    bool read_parameters(std::istream& stream) {
+        return fc_0.read_parameters(stream) && ac_0.read_parameters(stream)
+            && fc_1.read_parameters(stream) && ac_1.read_parameters(stream)
+            && fc_2.read_parameters(stream);
+    }
 
-  // Write network parameters
-  bool write_parameters(std::ostream& stream) const {
-    return   fc_0.write_parameters(stream)
-          && ac_0.write_parameters(stream)
-          && fc_1.write_parameters(stream)
-          && ac_1.write_parameters(stream)
-          && fc_2.write_parameters(stream);
-  }
+    // Write network parameters
+    bool write_parameters(std::ostream& stream) const {
+        return fc_0.write_parameters(stream) && ac_0.write_parameters(stream)
+            && fc_1.write_parameters(stream) && ac_1.write_parameters(stream)
+            && fc_2.write_parameters(stream);
+    }
 
-  std::int32_t propagate(const TransformedFeatureType* transformedFeatures)
-  {
-    struct alignas(CacheLineSize) Buffer
-    {
-      alignas(CacheLineSize) decltype(fc_0)::OutputBuffer fc_0_out;
-      alignas(CacheLineSize) decltype(ac_sqr_0)::OutputType ac_sqr_0_out[ceil_to_multiple<IndexType>(FC_0_OUTPUTS * 2, 32)];
-      alignas(CacheLineSize) decltype(ac_0)::OutputBuffer ac_0_out;
-      alignas(CacheLineSize) decltype(fc_1)::OutputBuffer fc_1_out;
-      alignas(CacheLineSize) decltype(ac_1)::OutputBuffer ac_1_out;
-      alignas(CacheLineSize) decltype(fc_2)::OutputBuffer fc_2_out;
+    std::int32_t propagate(const TransformedFeatureType* transformedFeatures) {
+        struct alignas(CacheLineSize) Buffer {
+            alignas(CacheLineSize) typename decltype(fc_0)::OutputBuffer fc_0_out;
+            alignas(CacheLineSize) typename decltype(ac_sqr_0)::OutputType
+              ac_sqr_0_out[ceil_to_multiple<IndexType>(FC_0_OUTPUTS * 2, 32)];
+            alignas(CacheLineSize) typename decltype(ac_0)::OutputBuffer ac_0_out;
+            alignas(CacheLineSize) typename decltype(fc_1)::OutputBuffer fc_1_out;
+            alignas(CacheLineSize) typename decltype(ac_1)::OutputBuffer ac_1_out;
+            alignas(CacheLineSize) typename decltype(fc_2)::OutputBuffer fc_2_out;
 
-      Buffer()
-      {
-          std::memset(this, 0, sizeof(*this));
-      }
-    };
+            Buffer() { std::memset(this, 0, sizeof(*this)); }
+        };
 
 #if defined(__clang__) && (__APPLE__)
-    // workaround for a bug reported with xcode 12
-    static thread_local auto tlsBuffer = std::make_unique<Buffer>();
-    // Access TLS only once, cache result.
-    Buffer& buffer = *tlsBuffer;
+        // workaround for a bug reported with xcode 12
+        static thread_local auto tlsBuffer = std::make_unique<Buffer>();
+        // Access TLS only once, cache result.
+        Buffer& buffer = *tlsBuffer;
 #else
-    alignas(CacheLineSize) static thread_local Buffer buffer;
+        alignas(CacheLineSize) static thread_local Buffer buffer;
 #endif
 
-    fc_0.propagate(transformedFeatures, buffer.fc_0_out);
-    ac_sqr_0.propagate(buffer.fc_0_out, buffer.ac_sqr_0_out);
-    ac_0.propagate(buffer.fc_0_out, buffer.ac_0_out);
-    std::memcpy(buffer.ac_sqr_0_out + FC_0_OUTPUTS, buffer.ac_0_out, FC_0_OUTPUTS * sizeof(decltype(ac_0)::OutputType));
-    fc_1.propagate(buffer.ac_sqr_0_out, buffer.fc_1_out);
-    ac_1.propagate(buffer.fc_1_out, buffer.ac_1_out);
-    fc_2.propagate(buffer.ac_1_out, buffer.fc_2_out);
+        fc_0.propagate(transformedFeatures, buffer.fc_0_out);
+        ac_sqr_0.propagate(buffer.fc_0_out, buffer.ac_sqr_0_out);
+        ac_0.propagate(buffer.fc_0_out, buffer.ac_0_out);
+        std::memcpy(buffer.ac_sqr_0_out + FC_0_OUTPUTS, buffer.ac_0_out,
+                    FC_0_OUTPUTS * sizeof(typename decltype(ac_0)::OutputType));
+        fc_1.propagate(buffer.ac_sqr_0_out, buffer.fc_1_out);
+        ac_1.propagate(buffer.fc_1_out, buffer.ac_1_out);
+        fc_2.propagate(buffer.ac_1_out, buffer.fc_2_out);
 
-    // buffer.fc_0_out[FC_0_OUTPUTS] is such that 1.0 is equal to 127*(1<<WeightScaleBits) in quantized form
-    // but we want 1.0 to be equal to 600*OutputScale
-    std::int32_t fwdOut = int(buffer.fc_0_out[FC_0_OUTPUTS]) * (600*OutputScale) / (127*(1<<WeightScaleBits));
-    std::int32_t outputValue = buffer.fc_2_out[0] + fwdOut;
+        // buffer.fc_0_out[FC_0_OUTPUTS] is such that 1.0 is equal to 127*(1<<WeightScaleBits) in
+        // quantized form, but we want 1.0 to be equal to 600*OutputScale
+        std::int32_t fwdOut =
+          (buffer.fc_0_out[FC_0_OUTPUTS]) * (600 * OutputScale) / (127 * (1 << WeightScaleBits));
+        std::int32_t outputValue = buffer.fc_2_out[0] + fwdOut;
 
-    return outputValue;
-  }
+        return outputValue;
+    }
 };
 
 }  // namespace Stockfish::Eval::NNUE
 
-#endif // #ifndef NNUE_ARCHITECTURE_H_INCLUDED
+#endif  // #ifndef NNUE_ARCHITECTURE_H_INCLUDED

src/nnue/nnue_common.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,221 +21,264 @@
 #ifndef NNUE_COMMON_H_INCLUDED
 #define NNUE_COMMON_H_INCLUDED
 
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
 #include <cstring>
 #include <iostream>
+#include <type_traits>
 
-#include "../misc.h"  // for IsLittleEndian
+#include "../misc.h"
 
 #if defined(USE_AVX2)
-#include <immintrin.h>
+    #include <immintrin.h>
 
 #elif defined(USE_SSE41)
-#include <smmintrin.h>
+    #include <smmintrin.h>
 
 #elif defined(USE_SSSE3)
-#include <tmmintrin.h>
+    #include <tmmintrin.h>
 
 #elif defined(USE_SSE2)
-#include <emmintrin.h>
-
-#elif defined(USE_MMX)
-#include <mmintrin.h>
+    #include <emmintrin.h>
 
 #elif defined(USE_NEON)
-#include <arm_neon.h>
+    #include <arm_neon.h>
 #endif
 
 namespace Stockfish::Eval::NNUE {
 
-  // Version of the evaluation file
-  constexpr std::uint32_t Version = 0x7AF32F20u;
+// Version of the evaluation file
+constexpr std::uint32_t Version = 0x7AF32F20u;
 
-  // Constant used in evaluation value calculation
-  constexpr int OutputScale = 16;
-  constexpr int WeightScaleBits = 6;
+// Constant used in evaluation value calculation
+constexpr int OutputScale     = 16;
+constexpr int WeightScaleBits = 6;
 
-  // Size of cache line (in bytes)
-  constexpr std::size_t CacheLineSize = 64;
+// Size of cache line (in bytes)
+constexpr std::size_t CacheLineSize = 64;
 
-  constexpr const char Leb128MagicString[] = "COMPRESSED_LEB128";
-  constexpr const std::size_t Leb128MagicStringSize = sizeof(Leb128MagicString) - 1;
+constexpr const char        Leb128MagicString[]   = "COMPRESSED_LEB128";
+constexpr const std::size_t Leb128MagicStringSize = sizeof(Leb128MagicString) - 1;
 
-  // SIMD width (in bytes)
-  #if defined(USE_AVX2)
-  constexpr std::size_t SimdWidth = 32;
+// SIMD width (in bytes)
+#if defined(USE_AVX2)
+constexpr std::size_t SimdWidth = 32;
 
-  #elif defined(USE_SSE2)
-  constexpr std::size_t SimdWidth = 16;
+#elif defined(USE_SSE2)
+constexpr std::size_t SimdWidth = 16;
 
-  #elif defined(USE_MMX)
-  constexpr std::size_t SimdWidth = 8;
+#elif defined(USE_NEON)
+constexpr std::size_t SimdWidth = 16;
+#endif
 
-  #elif defined(USE_NEON)
-  constexpr std::size_t SimdWidth = 16;
-  #endif
+constexpr std::size_t MaxSimdWidth = 32;
 
-  constexpr std::size_t MaxSimdWidth = 32;
+// Type of input feature after conversion
+using TransformedFeatureType = std::uint8_t;
+using IndexType              = std::uint32_t;
 
-  // Type of input feature after conversion
-  using TransformedFeatureType = std::uint8_t;
-  using IndexType = std::uint32_t;
+// Round n up to be a multiple of base
+template<typename IntType>
+constexpr IntType ceil_to_multiple(IntType n, IntType base) {
+    return (n + base - 1) / base * base;
+}
 
-  // Round n up to be a multiple of base
-  template <typename IntType>
-  constexpr IntType ceil_to_multiple(IntType n, IntType base) {
-      return (n + base - 1) / base * base;
-  }
 
-  // read_little_endian() is our utility to read an integer (signed or unsigned, any size)
-  // from a stream in little-endian order. We swap the byte order after the read if
-  // necessary to return a result with the byte ordering of the compiling machine.
-  template <typename IntType>
-  inline IntType read_little_endian(std::istream& stream) {
-      IntType result;
+// Utility to read an integer (signed or unsigned, any size)
+// from a stream in little-endian order. We swap the byte order after the read if
+// necessary to return a result with the byte ordering of the compiling machine.
+template<typename IntType>
+inline IntType read_little_endian(std::istream& stream) {
+    IntType result;
 
-      if (IsLittleEndian)
-          stream.read(reinterpret_cast<char*>(&result), sizeof(IntType));
-      else
-      {
-          std::uint8_t u[sizeof(IntType)];
-          typename std::make_unsigned<IntType>::type v = 0;
+    if (IsLittleEndian)
+        stream.read(reinterpret_cast<char*>(&result), sizeof(IntType));
+    else
+    {
+        std::uint8_t                  u[sizeof(IntType)];
+        std::make_unsigned_t<IntType> v = 0;
 
-          stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
-          for (std::size_t i = 0; i < sizeof(IntType); ++i)
-              v = (v << 8) | u[sizeof(IntType) - i - 1];
+        stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
+        for (std::size_t i = 0; i < sizeof(IntType); ++i)
+            v = (v << 8) | u[sizeof(IntType) - i - 1];
 
-          std::memcpy(&result, &v, sizeof(IntType));
-      }
+        std::memcpy(&result, &v, sizeof(IntType));
+    }
 
-      return result;
-  }
+    return result;
+}
 
-  // write_little_endian() is our utility to write an integer (signed or unsigned, any size)
-  // to a stream in little-endian order. We swap the byte order before the write if
-  // necessary to always write in little endian order, independently of the byte
-  // ordering of the compiling machine.
-  template <typename IntType>
-  inline void write_little_endian(std::ostream& stream, IntType value) {
 
-      if (IsLittleEndian)
-          stream.write(reinterpret_cast<const char*>(&value), sizeof(IntType));
-      else
-      {
-          std::uint8_t u[sizeof(IntType)];
-          typename std::make_unsigned<IntType>::type v = value;
+// Utility to write an integer (signed or unsigned, any size)
+// to a stream in little-endian order. We swap the byte order before the write if
+// necessary to always write in little-endian order, independently of the byte
+// ordering of the compiling machine.
+template<typename IntType>
+inline void write_little_endian(std::ostream& stream, IntType value) {
 
-          std::size_t i = 0;
-          // if constexpr to silence the warning about shift by 8
-          if constexpr (sizeof(IntType) > 1)
-          {
+    if (IsLittleEndian)
+        stream.write(reinterpret_cast<const char*>(&value), sizeof(IntType));
+    else
+    {
+        std::uint8_t                  u[sizeof(IntType)];
+        std::make_unsigned_t<IntType> v = value;
+
+        std::size_t i = 0;
+        // if constexpr to silence the warning about shift by 8
+        if constexpr (sizeof(IntType) > 1)
+        {
             for (; i + 1 < sizeof(IntType); ++i)
             {
-                u[i] = (std::uint8_t)v;
+                u[i] = std::uint8_t(v);
                 v >>= 8;
             }
-          }
-          u[i] = (std::uint8_t)v;
+        }
+        u[i] = std::uint8_t(v);
 
-          stream.write(reinterpret_cast<char*>(u), sizeof(IntType));
-      }
-  }
+        stream.write(reinterpret_cast<char*>(u), sizeof(IntType));
+    }
+}
 
-  // read_little_endian(s, out, N) : read integers in bulk from a little indian stream.
-  // This reads N integers from stream s and put them in array out.
-  template <typename IntType>
-  inline void read_little_endian(std::istream& stream, IntType* out, std::size_t count) {
-      if (IsLittleEndian)
-          stream.read(reinterpret_cast<char*>(out), sizeof(IntType) * count);
-      else
-          for (std::size_t i = 0; i < count; ++i)
-              out[i] = read_little_endian<IntType>(stream);
-  }
 
-  // write_little_endian(s, values, N) : write integers in bulk to a little indian stream.
-  // This takes N integers from array values and writes them on stream s.
-  template <typename IntType>
-  inline void write_little_endian(std::ostream& stream, const IntType* values, std::size_t count) {
-      if (IsLittleEndian)
-          stream.write(reinterpret_cast<const char*>(values), sizeof(IntType) * count);
-      else
-          for (std::size_t i = 0; i < count; ++i)
-              write_little_endian<IntType>(stream, values[i]);
-  }
+// Read integers in bulk from a little-endian stream.
+// This reads N integers from stream s and puts them in array out.
+template<typename IntType>
+inline void read_little_endian(std::istream& stream, IntType* out, std::size_t count) {
+    if (IsLittleEndian)
+        stream.read(reinterpret_cast<char*>(out), sizeof(IntType) * count);
+    else
+        for (std::size_t i = 0; i < count; ++i)
+            out[i] = read_little_endian<IntType>(stream);
+}
 
-  template <typename IntType>
-  inline void read_leb_128(std::istream& stream, IntType* out, std::size_t count) {
-      static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
-      char leb128MagicString[Leb128MagicStringSize];
-      stream.read(leb128MagicString, Leb128MagicStringSize);
-      assert(strncmp(Leb128MagicString, leb128MagicString, Leb128MagicStringSize) == 0);
-      const std::uint32_t BUF_SIZE = 4096;
-      std::uint8_t buf[BUF_SIZE];
-      auto bytes_left = read_little_endian<std::uint32_t>(stream);
-      std::uint32_t buf_pos = BUF_SIZE;
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType result = 0;
-          size_t shift = 0;
-          do {
-              if (buf_pos == BUF_SIZE) {
-                  stream.read(reinterpret_cast<char*>(buf), std::min(bytes_left, BUF_SIZE));
-                  buf_pos = 0;
-              }
-              std::uint8_t byte = buf[buf_pos++];
-              --bytes_left;
-              result |= (byte & 0x7f) << shift;
-              shift += 7;
-              if ((byte & 0x80) == 0) {
-                  out[i] = sizeof(IntType) * 8 <= shift || (byte & 0x40) == 0 ? result : result | ~((1 << shift) - 1);
-                  break;
-              }
-          } while (shift < sizeof(IntType) * 8);
-      }
-      assert(bytes_left == 0);
-  }
 
-  template <typename IntType>
-  inline void write_leb_128(std::ostream& stream, const IntType* values, std::size_t count) {
-      static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
-      stream.write(Leb128MagicString, Leb128MagicStringSize);
-      std::uint32_t byte_count = 0;
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType value = values[i];
-          std::uint8_t byte;
-          do {
-              byte = value & 0x7f;
-              value >>= 7;
-              ++byte_count;
-          } while ((byte & 0x40) == 0 ? value != 0 : value != -1);
-      }
-      write_little_endian(stream, byte_count);
-      const std::uint32_t BUF_SIZE = 4096;
-      std::uint8_t buf[BUF_SIZE];
-      std::uint32_t buf_pos = 0;
-      auto flush = [&]() {
-          if (buf_pos > 0) {
-              stream.write(reinterpret_cast<char*>(buf), buf_pos);
-              buf_pos = 0;
-          }
-      };
-      auto write = [&](std::uint8_t byte) {
-          buf[buf_pos++] = byte;
-          if (buf_pos == BUF_SIZE) flush();
-      };
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType value = values[i];
-          while (true) {
-              std::uint8_t byte = value & 0x7f;
-              value >>= 7;
-              if ((byte & 0x40) == 0 ? value == 0 : value == -1) {
-                  write(byte);
-                  break;
-              }
-              write(byte | 0x80);
-          }
-      }
-      flush();
-  }
+// Write integers in bulk to a little-endian stream.
+// This takes N integers from array values and writes them on stream s.
+template<typename IntType>
+inline void write_little_endian(std::ostream& stream, const IntType* values, std::size_t count) {
+    if (IsLittleEndian)
+        stream.write(reinterpret_cast<const char*>(values), sizeof(IntType) * count);
+    else
+        for (std::size_t i = 0; i < count; ++i)
+            write_little_endian<IntType>(stream, values[i]);
+}
+
+
+// Read N signed integers from the stream s, putting them in the array out.
+// The stream is assumed to be compressed using the signed LEB128 format.
+// See https://en.wikipedia.org/wiki/LEB128 for a description of the compression scheme.
+template<typename IntType>
+inline void read_leb_128(std::istream& stream, IntType* out, std::size_t count) {
+
+    // Check the presence of our LEB128 magic string
+    char leb128MagicString[Leb128MagicStringSize];
+    stream.read(leb128MagicString, Leb128MagicStringSize);
+    assert(strncmp(Leb128MagicString, leb128MagicString, Leb128MagicStringSize) == 0);
+
+    static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
+
+    const std::uint32_t BUF_SIZE = 4096;
+    std::uint8_t        buf[BUF_SIZE];
+
+    auto bytes_left = read_little_endian<std::uint32_t>(stream);
+
+    std::uint32_t buf_pos = BUF_SIZE;
+    for (std::size_t i = 0; i < count; ++i)
+    {
+        IntType result = 0;
+        size_t  shift  = 0;
+        do
+        {
+            if (buf_pos == BUF_SIZE)
+            {
+                stream.read(reinterpret_cast<char*>(buf), std::min(bytes_left, BUF_SIZE));
+                buf_pos = 0;
+            }
+
+            std::uint8_t byte = buf[buf_pos++];
+            --bytes_left;
+            result |= (byte & 0x7f) << shift;
+            shift += 7;
+
+            if ((byte & 0x80) == 0)
+            {
+                out[i] = (sizeof(IntType) * 8 <= shift || (byte & 0x40) == 0)
+                         ? result
+                         : result | ~((1 << shift) - 1);
+                break;
+            }
+        } while (shift < sizeof(IntType) * 8);
+    }
+
+    assert(bytes_left == 0);
+}
+
+
+// Write signed integers to a stream with LEB128 compression.
+// This takes N integers from array values, compresses them with
+// the LEB128 algorithm and writes the result on the stream s.
+// See https://en.wikipedia.org/wiki/LEB128 for a description of the compression scheme.
+template<typename IntType>
+inline void write_leb_128(std::ostream& stream, const IntType* values, std::size_t count) {
+
+    // Write our LEB128 magic string
+    stream.write(Leb128MagicString, Leb128MagicStringSize);
+
+    static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
+
+    std::uint32_t byte_count = 0;
+    for (std::size_t i = 0; i < count; ++i)
+    {
+        IntType      value = values[i];
+        std::uint8_t byte;
+        do
+        {
+            byte = value & 0x7f;
+            value >>= 7;
+            ++byte_count;
+        } while ((byte & 0x40) == 0 ? value != 0 : value != -1);
+    }
+
+    write_little_endian(stream, byte_count);
+
+    const std::uint32_t BUF_SIZE = 4096;
+    std::uint8_t        buf[BUF_SIZE];
+    std::uint32_t       buf_pos = 0;
+
+    auto flush = [&]() {
+        if (buf_pos > 0)
+        {
+            stream.write(reinterpret_cast<char*>(buf), buf_pos);
+            buf_pos = 0;
+        }
+    };
+
+    auto write = [&](std::uint8_t byte) {
+        buf[buf_pos++] = byte;
+        if (buf_pos == BUF_SIZE)
+            flush();
+    };
+
+    for (std::size_t i = 0; i < count; ++i)
+    {
+        IntType value = values[i];
+        while (true)
+        {
+            std::uint8_t byte = value & 0x7f;
+            value >>= 7;
+            if ((byte & 0x40) == 0 ? value == 0 : value == -1)
+            {
+                write(byte);
+                break;
+            }
+            write(byte | 0x80);
+        }
+    }
+
+    flush();
+}
 
 }  // namespace Stockfish::Eval::NNUE
 
-#endif // #ifndef NNUE_COMMON_H_INCLUDED
+#endif  // #ifndef NNUE_COMMON_H_INCLUDED

src/pawns.cpp

@@ -1,305 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <algorithm>
-#include <cassert>
-
-#include "bitboard.h"
-#include "pawns.h"
-#include "position.h"
-#include "thread.h"
-
-namespace Stockfish {
-
-namespace {
-
-  #define V Value
-  #define S(mg, eg) make_score(mg, eg)
-
-  // Pawn penalties
-  constexpr Score Backward      = S( 6, 19);
-  constexpr Score Doubled       = S(11, 51);
-  constexpr Score DoubledEarly  = S(17,  7);
-  constexpr Score Isolated      = S( 1, 20);
-  constexpr Score WeakLever     = S( 2, 57);
-  constexpr Score WeakUnopposed = S(15, 18);
-
-  // Bonus for blocked pawns at 5th or 6th rank
-  constexpr Score BlockedPawn[2] = { S(-19, -8), S(-7, 3) };
-
-  constexpr Score BlockedStorm[RANK_NB] = {
-    S(0, 0), S(0, 0), S(64, 75), S(-3, 14), S(-12, 19), S(-7, 4), S(-10, 5)
-  };
-
-  // Connected pawn bonus
-  constexpr int Connected[RANK_NB] = { 0, 3, 7, 7, 15, 54, 86 };
-
-  // Strength of pawn shelter for our king by [distance from edge][rank].
-  // RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
-  constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
-    { V(-2), V(85), V(95), V(53), V(39), V(23), V(25) },
-    { V(-55), V(64), V(32), V(-55), V(-30), V(-11), V(-61) },
-    { V(-11), V(75), V(19), V(-6), V(26), V(9), V(-47) },
-    { V(-41), V(-11), V(-27), V(-58), V(-42), V(-66), V(-163) }
-  };
-
-  // Danger of enemy pawns moving toward our king by [distance from edge][rank].
-  // RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn
-  // is behind our king. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
-  // on edge, likely blocked by our king.
-  constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
-    { V(94), V(-280), V(-170), V(90), V(59), V(47), V(53) },
-    { V(43), V(-17), V(128), V(39), V(26), V(-17), V(15) },
-    { V(-9), V(62), V(170), V(34), V(-5), V(-20), V(-11) },
-    { V(-27), V(-19), V(106), V(10), V(2), V(-13), V(-24) }
-  };
-
-
-  // KingOnFile[semi-open Us][semi-open Them] contains bonuses/penalties
-  // for king when the king is on a semi-open or open file.
-  constexpr Score KingOnFile[2][2] = {{ S(-18,11), S(-6,-3)  },
-                                     {  S(  0, 0), S( 5,-4) }};
-
-  #undef S
-  #undef V
-
-
-  /// evaluate() calculates a score for the static pawn structure of the given position.
-  /// We cannot use the location of pieces or king in this function, as the evaluation
-  /// of the pawn structure will be stored in a small cache for speed reasons, and will
-  /// be re-used even when the pieces have moved.
-
-  template<Color Us>
-  Score evaluate(const Position& pos, Pawns::Entry* e) {
-
-    constexpr Color     Them = ~Us;
-    constexpr Direction Up   = pawn_push(Us);
-    constexpr Direction Down = -Up;
-
-    Bitboard neighbours, stoppers, support, phalanx, opposed;
-    Bitboard lever, leverPush, blocked;
-    Square s;
-    bool backward, passed, doubled;
-    Score score = SCORE_ZERO;
-    Bitboard b = pos.pieces(Us, PAWN);
-
-    Bitboard ourPawns   = pos.pieces(  Us, PAWN);
-    Bitboard theirPawns = pos.pieces(Them, PAWN);
-
-    Bitboard doubleAttackThem = pawn_double_attacks_bb<Them>(theirPawns);
-
-    e->passedPawns[Us] = 0;
-    e->kingSquares[Us] = SQ_NONE;
-    e->pawnAttacks[Us] = e->pawnAttacksSpan[Us] = pawn_attacks_bb<Us>(ourPawns);
-    e->blockedCount += popcount(shift<Up>(ourPawns) & (theirPawns | doubleAttackThem));
-
-    // Loop through all pawns of the current color and score each pawn
-    while (b)
-    {
-        s = pop_lsb(b);
-
-        assert(pos.piece_on(s) == make_piece(Us, PAWN));
-
-        Rank r = relative_rank(Us, s);
-
-        // Flag the pawn
-        opposed    = theirPawns & forward_file_bb(Us, s);
-        blocked    = theirPawns & (s + Up);
-        stoppers   = theirPawns & passed_pawn_span(Us, s);
-        lever      = theirPawns & pawn_attacks_bb(Us, s);
-        leverPush  = theirPawns & pawn_attacks_bb(Us, s + Up);
-        doubled    = ourPawns   & (s - Up);
-        neighbours = ourPawns   & adjacent_files_bb(s);
-        phalanx    = neighbours & rank_bb(s);
-        support    = neighbours & rank_bb(s - Up);
-
-        if (doubled)
-        {
-            // Additional doubled penalty if none of their pawns is fixed
-            if (!(ourPawns & shift<Down>(theirPawns | pawn_attacks_bb<Them>(theirPawns))))
-                score -= DoubledEarly;
-        }
-
-        // A pawn is backward when it is behind all pawns of the same color on
-        // the adjacent files and cannot safely advance.
-        backward =  !(neighbours & forward_ranks_bb(Them, s + Up))
-                  && (leverPush | blocked);
-
-        // Compute additional span if pawn is not backward nor blocked
-        if (!backward && !blocked)
-            e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
-
-        // A pawn is passed if one of the three following conditions is true:
-        // (a) there is no stoppers except some levers
-        // (b) the only stoppers are the leverPush, but we outnumber them
-        // (c) there is only one front stopper which can be levered.
-        //     (Refined in Evaluation::passed)
-        passed =   !(stoppers ^ lever)
-                || (   !(stoppers ^ leverPush)
-                    && popcount(phalanx) >= popcount(leverPush))
-                || (   stoppers == blocked && r >= RANK_5
-                    && (shift<Up>(support) & ~(theirPawns | doubleAttackThem)));
-
-        passed &= !(forward_file_bb(Us, s) & ourPawns);
-
-        // Passed pawns will be properly scored later in evaluation when we have
-        // full attack info.
-        if (passed)
-            e->passedPawns[Us] |= s;
-
-        // Score this pawn
-        if (support | phalanx)
-        {
-            int v =  Connected[r] * (2 + bool(phalanx) - bool(opposed))
-                   + 22 * popcount(support);
-
-            score += make_score(v, v * (r - 2) / 4);
-        }
-
-        else if (!neighbours)
-        {
-            if (     opposed
-                &&  (ourPawns & forward_file_bb(Them, s))
-                && !(theirPawns & adjacent_files_bb(s)))
-                score -= Doubled;
-            else
-                score -=  Isolated
-                        + WeakUnopposed * !opposed;
-        }
-
-        else if (backward)
-            score -=  Backward
-                    + WeakUnopposed * !opposed * bool(~(FileABB | FileHBB) & s);
-
-        if (!support)
-            score -=  Doubled * doubled
-                    + WeakLever * more_than_one(lever);
-
-        if (blocked && r >= RANK_5)
-            score += BlockedPawn[r - RANK_5];
-    }
-
-    return score;
-  }
-
-} // namespace
-
-namespace Pawns {
-
-
-/// Pawns::probe() looks up the current position's pawns configuration in
-/// the pawns hash table. It returns a pointer to the Entry if the position
-/// is found. Otherwise a new Entry is computed and stored there, so we don't
-/// have to recompute all when the same pawns configuration occurs again.
-
-Entry* probe(const Position& pos) {
-
-  Key key = pos.pawn_key();
-  Entry* e = pos.this_thread()->pawnsTable[key];
-
-  if (e->key == key)
-      return e;
-
-  e->key = key;
-  e->blockedCount = 0;
-  e->scores[WHITE] = evaluate<WHITE>(pos, e);
-  e->scores[BLACK] = evaluate<BLACK>(pos, e);
-
-  return e;
-}
-
-
-/// Entry::evaluate_shelter() calculates the shelter bonus and the storm
-/// penalty for a king, looking at the king file and the two closest files.
-
-template<Color Us>
-Score Entry::evaluate_shelter(const Position& pos, Square ksq) const {
-
-  constexpr Color Them = ~Us;
-
-  Bitboard b = pos.pieces(PAWN) & ~forward_ranks_bb(Them, ksq);
-  Bitboard ourPawns = b & pos.pieces(Us) & ~pawnAttacks[Them];
-  Bitboard theirPawns = b & pos.pieces(Them);
-
-  Score bonus = make_score(5, 5);
-
-  File center = std::clamp(file_of(ksq), FILE_B, FILE_G);
-  for (File f = File(center - 1); f <= File(center + 1); ++f)
-  {
-      b = ourPawns & file_bb(f);
-      int ourRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
-
-      b = theirPawns & file_bb(f);
-      int theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
-
-      int d = edge_distance(f);
-      bonus += make_score(ShelterStrength[d][ourRank], 0);
-
-      if (ourRank && (ourRank == theirRank - 1))
-          bonus -= BlockedStorm[theirRank];
-      else
-          bonus -= make_score(UnblockedStorm[d][theirRank], 0);
-  }
-
-  // King On File
-  bonus -= KingOnFile[pos.is_on_semiopen_file(Us, ksq)][pos.is_on_semiopen_file(Them, ksq)];
-
-  return bonus;
-}
-
-
-/// Entry::do_king_safety() calculates a bonus for king safety. It is called only
-/// when king square changes, which is about 20% of total king_safety() calls.
-
-template<Color Us>
-Score Entry::do_king_safety(const Position& pos) {
-
-  Square ksq = pos.square<KING>(Us);
-  kingSquares[Us] = ksq;
-  castlingRights[Us] = pos.castling_rights(Us);
-  auto compare = [](Score a, Score b) { return mg_value(a) < mg_value(b); };
-
-  Score shelter = evaluate_shelter<Us>(pos, ksq);
-
-  // If we can castle use the bonus after castling if it is bigger
-
-  if (pos.can_castle(Us & KING_SIDE))
-      shelter = std::max(shelter, evaluate_shelter<Us>(pos, relative_square(Us, SQ_G1)), compare);
-
-  if (pos.can_castle(Us & QUEEN_SIDE))
-      shelter = std::max(shelter, evaluate_shelter<Us>(pos, relative_square(Us, SQ_C1)), compare);
-
-  // In endgame we like to bring our king near our closest pawn
-  Bitboard pawns = pos.pieces(Us, PAWN);
-  int minPawnDist = 6;
-
-  if (pawns & attacks_bb<KING>(ksq))
-      minPawnDist = 1;
-  else while (pawns)
-      minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(pawns)));
-
-  return shelter - make_score(0, 16 * minPawnDist);
-}
-
-// Explicit template instantiation
-template Score Entry::do_king_safety<WHITE>(const Position& pos);
-template Score Entry::do_king_safety<BLACK>(const Position& pos);
-
-} // namespace Pawns
-
-} // namespace Stockfish

src/pawns.h

@@ -1,70 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#ifndef PAWNS_H_INCLUDED
-#define PAWNS_H_INCLUDED
-
-#include "misc.h"
-#include "position.h"
-#include "types.h"
-
-namespace Stockfish::Pawns {
-
-/// Pawns::Entry contains various information about a pawn structure. A lookup
-/// to the pawn hash table (performed by calling the probe function) returns a
-/// pointer to an Entry object.
-
-struct Entry {
-
-  Score pawn_score(Color c) const { return scores[c]; }
-  Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; }
-  Bitboard passed_pawns(Color c) const { return passedPawns[c]; }
-  Bitboard pawn_attacks_span(Color c) const { return pawnAttacksSpan[c]; }
-  int passed_count() const { return popcount(passedPawns[WHITE] | passedPawns[BLACK]); }
-  int blocked_count() const { return blockedCount; }
-
-  template<Color Us>
-  Score king_safety(const Position& pos) {
-    return  kingSquares[Us] == pos.square<KING>(Us) && castlingRights[Us] == pos.castling_rights(Us)
-          ? kingSafety[Us] : (kingSafety[Us] = do_king_safety<Us>(pos));
-  }
-
-  template<Color Us>
-  Score do_king_safety(const Position& pos);
-
-  template<Color Us>
-  Score evaluate_shelter(const Position& pos, Square ksq) const;
-
-  Key key;
-  Score scores[COLOR_NB];
-  Bitboard passedPawns[COLOR_NB];
-  Bitboard pawnAttacks[COLOR_NB];
-  Bitboard pawnAttacksSpan[COLOR_NB];
-  Square kingSquares[COLOR_NB];
-  Score kingSafety[COLOR_NB];
-  int castlingRights[COLOR_NB];
-  int blockedCount;
-};
-
-using Table = HashTable<Entry, 131072>;
-
-Entry* probe(const Position& pos);
-
-} // namespace Stockfish::Pawns
-
-#endif // #ifndef PAWNS_H_INCLUDED

src/perft.h

@@ -0,0 +1,69 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef PERFT_H_INCLUDED
+#define PERFT_H_INCLUDED
+
+#include <cstdint>
+
+#include "movegen.h"
+#include "position.h"
+#include "types.h"
+#include "uci.h"
+
+namespace Stockfish {
+
+// Utility to verify move generation. All the leaf nodes up
+// to the given depth are generated and counted, and the sum is returned.
+template<bool Root>
+uint64_t perft(Position& pos, Depth depth) {
+
+    StateInfo st;
+    ASSERT_ALIGNED(&st, Eval::NNUE::CacheLineSize);
+
+    uint64_t   cnt, nodes = 0;
+    const bool leaf = (depth == 2);
+
+    for (const auto& m : MoveList<LEGAL>(pos))
+    {
+        if (Root && depth <= 1)
+            cnt = 1, nodes++;
+        else
+        {
+            pos.do_move(m, st);
+            cnt = leaf ? MoveList<LEGAL>(pos).size() : perft<false>(pos, depth - 1);
+            nodes += cnt;
+            pos.undo_move(m);
+        }
+        if (Root)
+            sync_cout << UCI::move(m, pos.is_chess960()) << ": " << cnt << sync_endl;
+    }
+    return nodes;
+}
+
+inline void perft(const std::string& fen, Depth depth, bool isChess960) {
+    StateListPtr states(new std::deque<StateInfo>(1));
+    Position     p;
+    p.set(fen, isChess960, &states->back());
+
+    uint64_t nodes = perft<true>(p, depth);
+    sync_cout << "\nNodes searched: " << nodes << "\n" << sync_endl;
+}
+}
+
+#endif  // PERFT_H_INCLUDED

src/position.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,430 +21,344 @@
 
 #include <cassert>
 #include <deque>
-#include <memory> // For std::unique_ptr
+#include <iosfwd>
+#include <memory>
 #include <string>
 
 #include "bitboard.h"
-#include "evaluate.h"
-#include "psqt.h"
-#include "types.h"
-
 #include "nnue/nnue_accumulator.h"
+#include "nnue/nnue_architecture.h"
+#include "types.h"
 
 namespace Stockfish {
 
-/// StateInfo struct stores information needed to restore a Position object to
-/// its previous state when we retract a move. Whenever a move is made on the
-/// board (by calling Position::do_move), a StateInfo object must be passed.
+class TranspositionTable;
+
+// StateInfo struct stores information needed to restore a Position object to
+// its previous state when we retract a move. Whenever a move is made on the
+// board (by calling Position::do_move), a StateInfo object must be passed.
 
 struct StateInfo {
 
-  // Copied when making a move
-  Key    pawnKey;
-  Key    materialKey;
-  Value  nonPawnMaterial[COLOR_NB];
-  int    castlingRights;
-  int    rule50;
-  int    pliesFromNull;
-  Square epSquare;
+    // Copied when making a move
+    Key    materialKey;
+    Key    pawnKey;
+    Value  nonPawnMaterial[COLOR_NB];
+    int    castlingRights;
+    int    rule50;
+    int    pliesFromNull;
+    Square epSquare;
 
-  // Not copied when making a move (will be recomputed anyhow)
-  Key        key;
-  Bitboard   checkersBB;
-  StateInfo* previous;
-  Bitboard   blockersForKing[COLOR_NB];
-  Bitboard   pinners[COLOR_NB];
-  Bitboard   checkSquares[PIECE_TYPE_NB];
-  Piece      capturedPiece;
-  int        repetition;
+    // Not copied when making a move (will be recomputed anyhow)
+    Key        key;
+    Bitboard   checkersBB;
+    StateInfo* previous;
+    Bitboard   blockersForKing[COLOR_NB];
+    Bitboard   pinners[COLOR_NB];
+    Bitboard   checkSquares[PIECE_TYPE_NB];
+    Piece      capturedPiece;
+    int        repetition;
 
-  // Used by NNUE
-  Eval::NNUE::Accumulator accumulator;
-  DirtyPiece dirtyPiece;
+    // Used by NNUE
+    Eval::NNUE::Accumulator<Eval::NNUE::TransformedFeatureDimensionsBig>   accumulatorBig;
+    Eval::NNUE::Accumulator<Eval::NNUE::TransformedFeatureDimensionsSmall> accumulatorSmall;
+    DirtyPiece                                                             dirtyPiece;
 };
 
 
-/// A list to keep track of the position states along the setup moves (from the
-/// start position to the position just before the search starts). Needed by
-/// 'draw by repetition' detection. Use a std::deque because pointers to
-/// elements are not invalidated upon list resizing.
+// A list to keep track of the position states along the setup moves (from the
+// start position to the position just before the search starts). Needed by
+// 'draw by repetition' detection. Use a std::deque because pointers to
+// elements are not invalidated upon list resizing.
 using StateListPtr = std::unique_ptr<std::deque<StateInfo>>;
 
 
-/// Position class stores information regarding the board representation as
-/// pieces, side to move, hash keys, castling info, etc. Important methods are
-/// do_move() and undo_move(), used by the search to update node info when
-/// traversing the search tree.
-class Thread;
-
+// Position class stores information regarding the board representation as
+// pieces, side to move, hash keys, castling info, etc. Important methods are
+// do_move() and undo_move(), used by the search to update node info when
+// traversing the search tree.
 class Position {
-public:
-  static void init();
+   public:
+    static void init();
 
-  Position() = default;
-  Position(const Position&) = delete;
-  Position& operator=(const Position&) = delete;
+    Position()                           = default;
+    Position(const Position&)            = delete;
+    Position& operator=(const Position&) = delete;
 
-  // FEN string input/output
-  Position& set(const std::string& fenStr, bool isChess960, StateInfo* si, Thread* th);
-  Position& set(const std::string& code, Color c, StateInfo* si);
-  std::string fen() const;
+    // FEN string input/output
+    Position&   set(const std::string& fenStr, bool isChess960, StateInfo* si);
+    Position&   set(const std::string& code, Color c, StateInfo* si);
+    std::string fen() const;
 
-  // Position representation
-  Bitboard pieces(PieceType pt) const;
-  template<typename ...PieceTypes> Bitboard pieces(PieceType pt, PieceTypes... pts) const;
-  Bitboard pieces(Color c) const;
-  template<typename ...PieceTypes> Bitboard pieces(Color c, PieceTypes... pts) const;
-  Piece piece_on(Square s) const;
-  Square ep_square() const;
-  bool empty(Square s) const;
-  template<PieceType Pt> int count(Color c) const;
-  template<PieceType Pt> int count() const;
-  template<PieceType Pt> Square square(Color c) const;
-  bool is_on_semiopen_file(Color c, Square s) const;
+    // Position representation
+    Bitboard pieces(PieceType pt = ALL_PIECES) const;
+    template<typename... PieceTypes>
+    Bitboard pieces(PieceType pt, PieceTypes... pts) const;
+    Bitboard pieces(Color c) const;
+    template<typename... PieceTypes>
+    Bitboard pieces(Color c, PieceTypes... pts) const;
+    Piece    piece_on(Square s) const;
+    Square   ep_square() const;
+    bool     empty(Square s) const;
+    template<PieceType Pt>
+    int count(Color c) const;
+    template<PieceType Pt>
+    int count() const;
+    template<PieceType Pt>
+    Square square(Color c) const;
 
-  // Castling
-  CastlingRights castling_rights(Color c) const;
-  bool can_castle(CastlingRights cr) const;
-  bool castling_impeded(CastlingRights cr) const;
-  Square castling_rook_square(CastlingRights cr) const;
+    // Castling
+    CastlingRights castling_rights(Color c) const;
+    bool           can_castle(CastlingRights cr) const;
+    bool           castling_impeded(CastlingRights cr) const;
+    Square         castling_rook_square(CastlingRights cr) const;
 
-  // Checking
-  Bitboard checkers() const;
-  Bitboard blockers_for_king(Color c) const;
-  Bitboard check_squares(PieceType pt) const;
-  Bitboard pinners(Color c) const;
+    // Checking
+    Bitboard checkers() const;
+    Bitboard blockers_for_king(Color c) const;
+    Bitboard check_squares(PieceType pt) const;
+    Bitboard pinners(Color c) const;
 
-  // Attacks to/from a given square
-  Bitboard attackers_to(Square s) const;
-  Bitboard attackers_to(Square s, Bitboard occupied) const;
-  Bitboard slider_blockers(Bitboard sliders, Square s, Bitboard& pinners) const;
-  template<PieceType Pt> Bitboard attacks_by(Color c) const;
+    // Attacks to/from a given square
+    Bitboard attackers_to(Square s) const;
+    Bitboard attackers_to(Square s, Bitboard occupied) const;
+    void     update_slider_blockers(Color c) const;
+    template<PieceType Pt>
+    Bitboard attacks_by(Color c) const;
 
-  // Properties of moves
-  bool legal(Move m) const;
-  bool pseudo_legal(const Move m) const;
-  bool capture(Move m) const;
-  bool capture_stage(Move m) const;
-  bool gives_check(Move m) const;
-  Piece moved_piece(Move m) const;
-  Piece captured_piece() const;
+    // Properties of moves
+    bool  legal(Move m) const;
+    bool  pseudo_legal(const Move m) const;
+    bool  capture(Move m) const;
+    bool  capture_stage(Move m) const;
+    bool  gives_check(Move m) const;
+    Piece moved_piece(Move m) const;
+    Piece captured_piece() const;
 
-  // Piece specific
-  bool pawn_passed(Color c, Square s) const;
-  bool opposite_bishops() const;
-  int  pawns_on_same_color_squares(Color c, Square s) const;
+    // Doing and undoing moves
+    void do_move(Move m, StateInfo& newSt);
+    void do_move(Move m, StateInfo& newSt, bool givesCheck);
+    void undo_move(Move m);
+    void do_null_move(StateInfo& newSt, TranspositionTable& tt);
+    void undo_null_move();
 
-  // Doing and undoing moves
-  void do_move(Move m, StateInfo& newSt);
-  void do_move(Move m, StateInfo& newSt, bool givesCheck);
-  void undo_move(Move m);
-  void do_null_move(StateInfo& newSt);
-  void undo_null_move();
+    // Static Exchange Evaluation
+    bool see_ge(Move m, int threshold = 0) const;
 
-  // Static Exchange Evaluation
-  bool see_ge(Move m, Value threshold = VALUE_ZERO) const;
-  bool see_ge(Move m, Bitboard& occupied, Value threshold = VALUE_ZERO) const;
+    // Accessing hash keys
+    Key key() const;
+    Key key_after(Move m) const;
+    Key material_key() const;
+    Key pawn_key() const;
 
-  // Accessing hash keys
-  Key key() const;
-  Key key_after(Move m) const;
-  Key material_key() const;
-  Key pawn_key() const;
+    // Other properties of the position
+    Color side_to_move() const;
+    int   game_ply() const;
+    bool  is_chess960() const;
+    bool  is_draw(int ply) const;
+    bool  has_game_cycle(int ply) const;
+    bool  has_repeated() const;
+    int   rule50_count() const;
+    Value non_pawn_material(Color c) const;
+    Value non_pawn_material() const;
 
-  // Other properties of the position
-  Color side_to_move() const;
-  int game_ply() const;
-  bool is_chess960() const;
-  Thread* this_thread() const;
-  bool is_draw(int ply) const;
-  bool has_game_cycle(int ply) const;
-  bool has_repeated() const;
-  int rule50_count() const;
-  Score psq_score() const;
-  Value psq_eg_stm() const;
-  Value non_pawn_material(Color c) const;
-  Value non_pawn_material() const;
+    // Position consistency check, for debugging
+    bool pos_is_ok() const;
+    void flip();
 
-  // Position consistency check, for debugging
-  bool pos_is_ok() const;
-  void flip();
+    // Used by NNUE
+    StateInfo* state() const;
 
-  // Used by NNUE
-  StateInfo* state() const;
+    void put_piece(Piece pc, Square s);
+    void remove_piece(Square s);
 
-  void put_piece(Piece pc, Square s);
-  void remove_piece(Square s);
+   private:
+    // Initialization helpers (used while setting up a position)
+    void set_castling_right(Color c, Square rfrom);
+    void set_state() const;
+    void set_check_info() const;
 
-private:
-  // Initialization helpers (used while setting up a position)
-  void set_castling_right(Color c, Square rfrom);
-  void set_state() const;
-  void set_check_info() const;
+    // Other helpers
+    void move_piece(Square from, Square to);
+    template<bool Do>
+    void do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto);
+    template<bool AfterMove>
+    Key adjust_key50(Key k) const;
 
-  // Other helpers
-  void move_piece(Square from, Square to);
-  template<bool Do>
-  void do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto);
-  template<bool AfterMove>
-  Key adjust_key50(Key k) const;
-
-  // Data members
-  Piece board[SQUARE_NB];
-  Bitboard byTypeBB[PIECE_TYPE_NB];
-  Bitboard byColorBB[COLOR_NB];
-  int pieceCount[PIECE_NB];
-  int castlingRightsMask[SQUARE_NB];
-  Square castlingRookSquare[CASTLING_RIGHT_NB];
-  Bitboard castlingPath[CASTLING_RIGHT_NB];
-  Thread* thisThread;
-  StateInfo* st;
-  int gamePly;
-  Color sideToMove;
-  Score psq;
-  bool chess960;
+    // Data members
+    Piece      board[SQUARE_NB];
+    Bitboard   byTypeBB[PIECE_TYPE_NB];
+    Bitboard   byColorBB[COLOR_NB];
+    int        pieceCount[PIECE_NB];
+    int        castlingRightsMask[SQUARE_NB];
+    Square     castlingRookSquare[CASTLING_RIGHT_NB];
+    Bitboard   castlingPath[CASTLING_RIGHT_NB];
+    StateInfo* st;
+    int        gamePly;
+    Color      sideToMove;
+    bool       chess960;
 };
 
 std::ostream& operator<<(std::ostream& os, const Position& pos);
 
-inline Color Position::side_to_move() const {
-  return sideToMove;
-}
+inline Color Position::side_to_move() const { return sideToMove; }
 
 inline Piece Position::piece_on(Square s) const {
-  assert(is_ok(s));
-  return board[s];
+    assert(is_ok(s));
+    return board[s];
 }
 
-inline bool Position::empty(Square s) const {
-  return piece_on(s) == NO_PIECE;
-}
+inline bool Position::empty(Square s) const { return piece_on(s) == NO_PIECE; }
 
-inline Piece Position::moved_piece(Move m) const {
-  return piece_on(from_sq(m));
-}
+inline Piece Position::moved_piece(Move m) const { return piece_on(m.from_sq()); }
 
-inline Bitboard Position::pieces(PieceType pt = ALL_PIECES) const {
-  return byTypeBB[pt];
-}
+inline Bitboard Position::pieces(PieceType pt) const { return byTypeBB[pt]; }
 
-template<typename ...PieceTypes>
+template<typename... PieceTypes>
 inline Bitboard Position::pieces(PieceType pt, PieceTypes... pts) const {
-  return pieces(pt) | pieces(pts...);
+    return pieces(pt) | pieces(pts...);
 }
 
-inline Bitboard Position::pieces(Color c) const {
-  return byColorBB[c];
-}
+inline Bitboard Position::pieces(Color c) const { return byColorBB[c]; }
 
-template<typename ...PieceTypes>
+template<typename... PieceTypes>
 inline Bitboard Position::pieces(Color c, PieceTypes... pts) const {
-  return pieces(c) & pieces(pts...);
+    return pieces(c) & pieces(pts...);
 }
 
-template<PieceType Pt> inline int Position::count(Color c) const {
-  return pieceCount[make_piece(c, Pt)];
+template<PieceType Pt>
+inline int Position::count(Color c) const {
+    return pieceCount[make_piece(c, Pt)];
 }
 
-template<PieceType Pt> inline int Position::count() const {
-  return count<Pt>(WHITE) + count<Pt>(BLACK);
+template<PieceType Pt>
+inline int Position::count() const {
+    return count<Pt>(WHITE) + count<Pt>(BLACK);
 }
 
-template<PieceType Pt> inline Square Position::square(Color c) const {
-  assert(count<Pt>(c) == 1);
-  return lsb(pieces(c, Pt));
+template<PieceType Pt>
+inline Square Position::square(Color c) const {
+    assert(count<Pt>(c) == 1);
+    return lsb(pieces(c, Pt));
 }
 
-inline Square Position::ep_square() const {
-  return st->epSquare;
-}
+inline Square Position::ep_square() const { return st->epSquare; }
 
-inline bool Position::is_on_semiopen_file(Color c, Square s) const {
-  return !(pieces(c, PAWN) & file_bb(s));
-}
-
-inline bool Position::can_castle(CastlingRights cr) const {
-  return st->castlingRights & cr;
-}
+inline bool Position::can_castle(CastlingRights cr) const { return st->castlingRights & cr; }
 
 inline CastlingRights Position::castling_rights(Color c) const {
-  return c & CastlingRights(st->castlingRights);
+    return c & CastlingRights(st->castlingRights);
 }
 
 inline bool Position::castling_impeded(CastlingRights cr) const {
-  assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO);
-
-  return pieces() & castlingPath[cr];
+    assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO);
+    return pieces() & castlingPath[cr];
 }
 
 inline Square Position::castling_rook_square(CastlingRights cr) const {
-  assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO);
-
-  return castlingRookSquare[cr];
+    assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO);
+    return castlingRookSquare[cr];
 }
 
-inline Bitboard Position::attackers_to(Square s) const {
-  return attackers_to(s, pieces());
-}
+inline Bitboard Position::attackers_to(Square s) const { return attackers_to(s, pieces()); }
 
 template<PieceType Pt>
 inline Bitboard Position::attacks_by(Color c) const {
 
-  if constexpr (Pt == PAWN)
-      return c == WHITE ? pawn_attacks_bb<WHITE>(pieces(WHITE, PAWN))
-                        : pawn_attacks_bb<BLACK>(pieces(BLACK, PAWN));
-  else
-  {
-      Bitboard threats = 0;
-      Bitboard attackers = pieces(c, Pt);
-      while (attackers)
-          threats |= attacks_bb<Pt>(pop_lsb(attackers), pieces());
-      return threats;
-  }
+    if constexpr (Pt == PAWN)
+        return c == WHITE ? pawn_attacks_bb<WHITE>(pieces(WHITE, PAWN))
+                          : pawn_attacks_bb<BLACK>(pieces(BLACK, PAWN));
+    else
+    {
+        Bitboard threats   = 0;
+        Bitboard attackers = pieces(c, Pt);
+        while (attackers)
+            threats |= attacks_bb<Pt>(pop_lsb(attackers), pieces());
+        return threats;
+    }
 }
 
-inline Bitboard Position::checkers() const {
-  return st->checkersBB;
-}
+inline Bitboard Position::checkers() const { return st->checkersBB; }
 
-inline Bitboard Position::blockers_for_king(Color c) const {
-  return st->blockersForKing[c];
-}
+inline Bitboard Position::blockers_for_king(Color c) const { return st->blockersForKing[c]; }
 
-inline Bitboard Position::pinners(Color c) const {
-  return st->pinners[c];
-}
+inline Bitboard Position::pinners(Color c) const { return st->pinners[c]; }
 
-inline Bitboard Position::check_squares(PieceType pt) const {
-  return st->checkSquares[pt];
-}
+inline Bitboard Position::check_squares(PieceType pt) const { return st->checkSquares[pt]; }
 
-inline bool Position::pawn_passed(Color c, Square s) const {
-  return !(pieces(~c, PAWN) & passed_pawn_span(c, s));
-}
-
-inline int Position::pawns_on_same_color_squares(Color c, Square s) const {
-  return popcount(pieces(c, PAWN) & ((DarkSquares & s) ? DarkSquares : ~DarkSquares));
-}
-
-inline Key Position::key() const {
-  return adjust_key50<false>(st->key);
-}
+inline Key Position::key() const { return adjust_key50<false>(st->key); }
 
 template<bool AfterMove>
-inline Key Position::adjust_key50(Key k) const
-{
-  return st->rule50 < 14 - AfterMove
-      ? k : k ^ make_key((st->rule50 - (14 - AfterMove)) / 8);
+inline Key Position::adjust_key50(Key k) const {
+    return st->rule50 < 14 - AfterMove ? k : k ^ make_key((st->rule50 - (14 - AfterMove)) / 8);
 }
 
-inline Key Position::pawn_key() const {
-  return st->pawnKey;
-}
+inline Key Position::pawn_key() const { return st->pawnKey; }
 
-inline Key Position::material_key() const {
-  return st->materialKey;
-}
+inline Key Position::material_key() const { return st->materialKey; }
 
-inline Score Position::psq_score() const {
-  return psq;
-}
-
-inline Value Position::psq_eg_stm() const {
-  return (sideToMove == WHITE ? 1 : -1) * eg_value(psq);
-}
-
-inline Value Position::non_pawn_material(Color c) const {
-  return st->nonPawnMaterial[c];
-}
+inline Value Position::non_pawn_material(Color c) const { return st->nonPawnMaterial[c]; }
 
 inline Value Position::non_pawn_material() const {
-  return non_pawn_material(WHITE) + non_pawn_material(BLACK);
+    return non_pawn_material(WHITE) + non_pawn_material(BLACK);
 }
 
-inline int Position::game_ply() const {
-  return gamePly;
-}
+inline int Position::game_ply() const { return gamePly; }
 
-inline int Position::rule50_count() const {
-  return st->rule50;
-}
+inline int Position::rule50_count() const { return st->rule50; }
 
-inline bool Position::opposite_bishops() const {
-  return   count<BISHOP>(WHITE) == 1
-        && count<BISHOP>(BLACK) == 1
-        && opposite_colors(square<BISHOP>(WHITE), square<BISHOP>(BLACK));
-}
-
-inline bool Position::is_chess960() const {
-  return chess960;
-}
+inline bool Position::is_chess960() const { return chess960; }
 
 inline bool Position::capture(Move m) const {
-  assert(is_ok(m));
-  return     (!empty(to_sq(m)) && type_of(m) != CASTLING)
-          ||  type_of(m) == EN_PASSANT;
+    assert(m.is_ok());
+    return (!empty(m.to_sq()) && m.type_of() != CASTLING) || m.type_of() == EN_PASSANT;
 }
 
-// returns true if a move is generated from the capture stage
-// having also queen promotions covered, i.e. consistency with the capture stage move generation
+// Returns true if a move is generated from the capture stage, having also
+// queen promotions covered, i.e. consistency with the capture stage move generation
 // is needed to avoid the generation of duplicate moves.
 inline bool Position::capture_stage(Move m) const {
-  assert(is_ok(m));
-  return  capture(m) || promotion_type(m) == QUEEN;
+    assert(m.is_ok());
+    return capture(m) || m.promotion_type() == QUEEN;
 }
 
-inline Piece Position::captured_piece() const {
-  return st->capturedPiece;
-}
-
-inline Thread* Position::this_thread() const {
-  return thisThread;
-}
+inline Piece Position::captured_piece() const { return st->capturedPiece; }
 
 inline void Position::put_piece(Piece pc, Square s) {
 
-  board[s] = pc;
-  byTypeBB[ALL_PIECES] |= byTypeBB[type_of(pc)] |= s;
-  byColorBB[color_of(pc)] |= s;
-  pieceCount[pc]++;
-  pieceCount[make_piece(color_of(pc), ALL_PIECES)]++;
-  psq += PSQT::psq[pc][s];
+    board[s] = pc;
+    byTypeBB[ALL_PIECES] |= byTypeBB[type_of(pc)] |= s;
+    byColorBB[color_of(pc)] |= s;
+    pieceCount[pc]++;
+    pieceCount[make_piece(color_of(pc), ALL_PIECES)]++;
 }
 
 inline void Position::remove_piece(Square s) {
 
-  Piece pc = board[s];
-  byTypeBB[ALL_PIECES] ^= s;
-  byTypeBB[type_of(pc)] ^= s;
-  byColorBB[color_of(pc)] ^= s;
-  board[s] = NO_PIECE;
-  pieceCount[pc]--;
-  pieceCount[make_piece(color_of(pc), ALL_PIECES)]--;
-  psq -= PSQT::psq[pc][s];
+    Piece pc = board[s];
+    byTypeBB[ALL_PIECES] ^= s;
+    byTypeBB[type_of(pc)] ^= s;
+    byColorBB[color_of(pc)] ^= s;
+    board[s] = NO_PIECE;
+    pieceCount[pc]--;
+    pieceCount[make_piece(color_of(pc), ALL_PIECES)]--;
 }
 
 inline void Position::move_piece(Square from, Square to) {
 
-  Piece pc = board[from];
-  Bitboard fromTo = from | to;
-  byTypeBB[ALL_PIECES] ^= fromTo;
-  byTypeBB[type_of(pc)] ^= fromTo;
-  byColorBB[color_of(pc)] ^= fromTo;
-  board[from] = NO_PIECE;
-  board[to] = pc;
-  psq += PSQT::psq[pc][to] - PSQT::psq[pc][from];
+    Piece    pc     = board[from];
+    Bitboard fromTo = from | to;
+    byTypeBB[ALL_PIECES] ^= fromTo;
+    byTypeBB[type_of(pc)] ^= fromTo;
+    byColorBB[color_of(pc)] ^= fromTo;
+    board[from] = NO_PIECE;
+    board[to]   = pc;
 }
 
-inline void Position::do_move(Move m, StateInfo& newSt) {
-  do_move(m, newSt, gives_check(m));
-}
+inline void Position::do_move(Move m, StateInfo& newSt) { do_move(m, newSt, gives_check(m)); }
 
-inline StateInfo* Position::state() const {
+inline StateInfo* Position::state() const { return st; }
 
-  return st;
-}
+}  // namespace Stockfish
 
-} // namespace Stockfish
-
-#endif // #ifndef POSITION_H_INCLUDED
+#endif  // #ifndef POSITION_H_INCLUDED

src/psqt.cpp

@@ -1,131 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-
-#include "psqt.h"
-
-#include <algorithm>
-
-#include "bitboard.h"
-#include "types.h"
-
-namespace Stockfish {
-
-namespace
-{
-
-auto constexpr S = make_score;
-
-// 'Bonus' contains Piece-Square parameters.
-// Scores are explicit for files A to D, implicitly mirrored for E to H.
-constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
-  { },
-  { },
-  { // Knight
-   { S(-175, -96), S(-92,-65), S(-74,-49), S(-73,-21) },
-   { S( -77, -67), S(-41,-54), S(-27,-18), S(-15,  8) },
-   { S( -61, -40), S(-17,-27), S(  6, -8), S( 12, 29) },
-   { S( -35, -35), S(  8, -2), S( 40, 13), S( 49, 28) },
-   { S( -34, -45), S( 13,-16), S( 44,  9), S( 51, 39) },
-   { S(  -9, -51), S( 22,-44), S( 58,-16), S( 53, 17) },
-   { S( -67, -69), S(-27,-50), S(  4,-51), S( 37, 12) },
-   { S(-201,-100), S(-83,-88), S(-56,-56), S(-26,-17) }
-  },
-  { // Bishop
-   { S(-37,-40), S(-4 ,-21), S( -6,-26), S(-16, -8) },
-   { S(-11,-26), S(  6, -9), S( 13,-12), S(  3,  1) },
-   { S(-5 ,-11), S( 15, -1), S( -4, -1), S( 12,  7) },
-   { S(-4 ,-14), S(  8, -4), S( 18,  0), S( 27, 12) },
-   { S(-8 ,-12), S( 20, -1), S( 15,-10), S( 22, 11) },
-   { S(-11,-21), S(  4,  4), S(  1,  3), S(  8,  4) },
-   { S(-12,-22), S(-10,-14), S(  4, -1), S(  0,  1) },
-   { S(-34,-32), S(  1,-29), S(-10,-26), S(-16,-17) }
-  },
-  { // Rook
-   { S(-31, -9), S(-20,-13), S(-14,-10), S(-5, -9) },
-   { S(-21,-12), S(-13, -9), S( -8, -1), S( 6, -2) },
-   { S(-25,  6), S(-11, -8), S( -1, -2), S( 3, -6) },
-   { S(-13, -6), S( -5,  1), S( -4, -9), S(-6,  7) },
-   { S(-27, -5), S(-15,  8), S( -4,  7), S( 3, -6) },
-   { S(-22,  6), S( -2,  1), S(  6, -7), S(12, 10) },
-   { S( -2,  4), S( 12,  5), S( 16, 20), S(18, -5) },
-   { S(-17, 18), S(-19,  0), S( -1, 19), S( 9, 13) }
-  },
-  { // Queen
-   { S( 3,-69), S(-5,-57), S(-5,-47), S( 4,-26) },
-   { S(-3,-54), S( 5,-31), S( 8,-22), S(12, -4) },
-   { S(-3,-39), S( 6,-18), S(13, -9), S( 7,  3) },
-   { S( 4,-23), S( 5, -3), S( 9, 13), S( 8, 24) },
-   { S( 0,-29), S(14, -6), S(12,  9), S( 5, 21) },
-   { S(-4,-38), S(10,-18), S( 6,-11), S( 8,  1) },
-   { S(-5,-50), S( 6,-27), S(10,-24), S( 8, -8) },
-   { S(-2,-74), S(-2,-52), S( 1,-43), S(-2,-34) }
-  },
-  { // King
-   { S(271,  1), S(327, 45), S(271, 85), S(198, 76) },
-   { S(278, 53), S(303,100), S(234,133), S(179,135) },
-   { S(195, 88), S(258,130), S(169,169), S(120,175) },
-   { S(164,103), S(190,156), S(138,172), S( 98,172) },
-   { S(154, 96), S(179,166), S(105,199), S( 70,199) },
-   { S(123, 92), S(145,172), S( 81,184), S( 31,191) },
-   { S( 88, 47), S(120,121), S( 65,116), S( 33,131) },
-   { S( 59, 11), S( 89, 59), S( 45, 73), S( -1, 78) }
-  }
-};
-
-constexpr Score PBonus[RANK_NB][FILE_NB] =
-  { // Pawn (asymmetric distribution)
-   { },
-   { S(  2, -8), S(  4, -6), S( 11,  9), S( 18,  5), S( 16, 16), S( 21,  6), S(  9, -6), S( -3,-18) },
-   { S( -9, -9), S(-15, -7), S( 11,-10), S( 15,  5), S( 31,  2), S( 23,  3), S(  6, -8), S(-20, -5) },
-   { S( -3,  7), S(-20,  1), S(  8, -8), S( 19, -2), S( 39,-14), S( 17,-13), S(  2,-11), S( -5, -6) },
-   { S( 11, 12), S( -4,  6), S(-11,  2), S(  2, -6), S( 11, -5), S(  0, -4), S(-12, 14), S(  5,  9) },
-   { S(  3, 27), S(-11, 18), S( -6, 19), S( 22, 29), S( -8, 30), S( -5,  9), S(-14,  8), S(-11, 14) },
-   { S( -7, -1), S(  6,-14), S( -2, 13), S(-11, 22), S(  4, 24), S(-14, 17), S( 10,  7), S( -9,  7) }
-  };
-
-} // namespace
-
-
-namespace PSQT
-{
-
-Score psq[PIECE_NB][SQUARE_NB];
-
-// PSQT::init() initializes piece-square tables: the white halves of the tables are
-// copied from Bonus[] and PBonus[], adding the piece value, then the black halves of
-// the tables are initialized by flipping and changing the sign of the white scores.
-void init() {
-
-  for (Piece pc : {W_PAWN, W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING})
-  {
-    Score score = make_score(PieceValue[MG][pc], PieceValue[EG][pc]);
-
-    for (Square s = SQ_A1; s <= SQ_H8; ++s)
-    {
-      File f = File(edge_distance(file_of(s)));
-      psq[ pc][s] = score + (type_of(pc) == PAWN ? PBonus[rank_of(s)][file_of(s)]
-                                                 : Bonus[pc][rank_of(s)][f]);
-      psq[~pc][flip_rank(s)] = -psq[pc][s];
-    }
-  }
-}
-
-} // namespace PSQT
-
-} // namespace Stockfish

src/psqt.h

@@ -1,38 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-
-#ifndef PSQT_H_INCLUDED
-#define PSQT_H_INCLUDED
-
-
-#include "types.h"
-
-
-namespace Stockfish::PSQT
-{
-
-extern Score psq[PIECE_NB][SQUARE_NB];
-
-// Fill psqt array from a set of internally linked parameters
-void init();
-
-} // namespace Stockfish::PSQT
-
-
-#endif // PSQT_H_INCLUDED

src/search.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,98 +19,243 @@
 #ifndef SEARCH_H_INCLUDED
 #define SEARCH_H_INCLUDED
 
+#include <array>
+#include <atomic>
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <memory>
 #include <vector>
+#include <string>
 
 #include "misc.h"
 #include "movepick.h"
+#include "position.h"
+#include "syzygy/tbprobe.h"
+#include "timeman.h"
 #include "types.h"
 
 namespace Stockfish {
 
-class Position;
+// Different node types, used as a template parameter
+enum NodeType {
+    NonPV,
+    PV,
+    Root
+};
+
+class TranspositionTable;
+class ThreadPool;
+class OptionsMap;
 
 namespace Search {
 
-
-/// Stack struct keeps track of the information we need to remember from nodes
-/// shallower and deeper in the tree during the search. Each search thread has
-/// its own array of Stack objects, indexed by the current ply.
-
+// Stack struct keeps track of the information we need to remember from nodes
+// shallower and deeper in the tree during the search. Each search thread has
+// its own array of Stack objects, indexed by the current ply.
 struct Stack {
-  Move* pv;
-  PieceToHistory* continuationHistory;
-  int ply;
-  Move currentMove;
-  Move excludedMove;
-  Move killers[2];
-  Value staticEval;
-  int statScore;
-  int moveCount;
-  bool inCheck;
-  bool ttPv;
-  bool ttHit;
-  int doubleExtensions;
-  int cutoffCnt;
+    Move*           pv;
+    PieceToHistory* continuationHistory;
+    int             ply;
+    Move            currentMove;
+    Move            excludedMove;
+    Move            killers[2];
+    Value           staticEval;
+    int             statScore;
+    int             moveCount;
+    bool            inCheck;
+    bool            ttPv;
+    bool            ttHit;
+    int             multipleExtensions;
+    int             cutoffCnt;
 };
 
 
-/// RootMove struct is used for moves at the root of the tree. For each root move
-/// we store a score and a PV (really a refutation in the case of moves which
-/// fail low). Score is normally set at -VALUE_INFINITE for all non-pv moves.
-
+// RootMove struct is used for moves at the root of the tree. For each root move
+// we store a score and a PV (really a refutation in the case of moves which
+// fail low). Score is normally set at -VALUE_INFINITE for all non-pv moves.
 struct RootMove {
 
-  explicit RootMove(Move m) : pv(1, m) {}
-  bool extract_ponder_from_tt(Position& pos);
-  bool operator==(const Move& m) const { return pv[0] == m; }
-  bool operator<(const RootMove& m) const { // Sort in descending order
-    return m.score != score ? m.score < score
-                            : m.previousScore < previousScore;
-  }
+    explicit RootMove(Move m) :
+        pv(1, m) {}
+    bool extract_ponder_from_tt(const TranspositionTable& tt, Position& pos);
+    bool operator==(const Move& m) const { return pv[0] == m; }
+    // Sort in descending order
+    bool operator<(const RootMove& m) const {
+        return m.score != score ? m.score < score : m.previousScore < previousScore;
+    }
 
-  Value score = -VALUE_INFINITE;
-  Value previousScore = -VALUE_INFINITE;
-  Value averageScore = -VALUE_INFINITE;
-  Value uciScore = -VALUE_INFINITE;
-  bool scoreLowerbound = false;
-  bool scoreUpperbound = false;
-  int selDepth = 0;
-  int tbRank = 0;
-  Value tbScore;
-  std::vector<Move> pv;
+    Value             score           = -VALUE_INFINITE;
+    Value             previousScore   = -VALUE_INFINITE;
+    Value             averageScore    = -VALUE_INFINITE;
+    Value             uciScore        = -VALUE_INFINITE;
+    bool              scoreLowerbound = false;
+    bool              scoreUpperbound = false;
+    int               selDepth        = 0;
+    int               tbRank          = 0;
+    Value             tbScore;
+    std::vector<Move> pv;
 };
 
 using RootMoves = std::vector<RootMove>;
 
 
-/// LimitsType struct stores information sent by GUI about available time to
-/// search the current move, maximum depth/time, or if we are in analysis mode.
-
+// LimitsType struct stores information sent by GUI about available time to
+// search the current move, maximum depth/time, or if we are in analysis mode.
 struct LimitsType {
 
-  LimitsType() { // Init explicitly due to broken value-initialization of non POD in MSVC
-    time[WHITE] = time[BLACK] = inc[WHITE] = inc[BLACK] = npmsec = movetime = TimePoint(0);
-    movestogo = depth = mate = perft = infinite = 0;
-    nodes = 0;
-  }
+    // Init explicitly due to broken value-initialization of non POD in MSVC
+    LimitsType() {
+        time[WHITE] = time[BLACK] = inc[WHITE] = inc[BLACK] = npmsec = movetime = TimePoint(0);
+        movestogo = depth = mate = perft = infinite = 0;
+        nodes                                       = 0;
+    }
 
-  bool use_time_management() const {
-    return time[WHITE] || time[BLACK];
-  }
+    bool use_time_management() const { return time[WHITE] || time[BLACK]; }
 
-  std::vector<Move> searchmoves;
-  TimePoint time[COLOR_NB], inc[COLOR_NB], npmsec, movetime, startTime;
-  int movestogo, depth, mate, perft, infinite;
-  int64_t nodes;
+    std::vector<Move> searchmoves;
+    TimePoint         time[COLOR_NB], inc[COLOR_NB], npmsec, movetime, startTime;
+    int               movestogo, depth, mate, perft, infinite;
+    uint64_t          nodes;
 };
 
-extern LimitsType Limits;
 
-void init();
-void clear();
+// The UCI stores the uci options, thread pool, and transposition table.
+// This struct is used to easily forward data to the Search::Worker class.
+struct SharedState {
+    SharedState(const OptionsMap&   optionsMap,
+                ThreadPool&         threadPool,
+                TranspositionTable& transpositionTable) :
+        options(optionsMap),
+        threads(threadPool),
+        tt(transpositionTable) {}
 
-} // namespace Search
+    const OptionsMap&   options;
+    ThreadPool&         threads;
+    TranspositionTable& tt;
+};
 
-} // namespace Stockfish
+class Worker;
 
-#endif // #ifndef SEARCH_H_INCLUDED
+// Null Object Pattern, implement a common interface for the SearchManagers.
+// A Null Object will be given to non-mainthread workers.
+class ISearchManager {
+   public:
+    virtual ~ISearchManager() {}
+    virtual void check_time(Search::Worker&) = 0;
+};
+
+// SearchManager manages the search from the main thread. It is responsible for
+// keeping track of the time, and storing data strictly related to the main thread.
+class SearchManager: public ISearchManager {
+   public:
+    void check_time(Search::Worker& worker) override;
+
+    std::string pv(const Search::Worker&     worker,
+                   const ThreadPool&         threads,
+                   const TranspositionTable& tt,
+                   Depth                     depth) const;
+
+    Stockfish::TimeManagement tm;
+    int                       callsCnt;
+    std::atomic_bool          ponder;
+
+    std::array<Value, 4> iterValue;
+    double               previousTimeReduction;
+    Value                bestPreviousScore;
+    Value                bestPreviousAverageScore;
+    bool                 stopOnPonderhit;
+
+    size_t id;
+};
+
+class NullSearchManager: public ISearchManager {
+   public:
+    void check_time(Search::Worker&) override {}
+};
+
+// Search::Worker is the class that does the actual search.
+// It is instantiated once per thread, and it is responsible for keeping track
+// of the search history, and storing data required for the search.
+class Worker {
+   public:
+    Worker(SharedState&, std::unique_ptr<ISearchManager>, size_t);
+
+    // Called at instantiation to initialize Reductions tables
+    // Reset histories, usually before a new game
+    void clear();
+
+    // Called when the program receives the UCI 'go' command.
+    // It searches from the root position and outputs the "bestmove".
+    void start_searching();
+
+    bool is_mainthread() const { return thread_idx == 0; }
+
+    // Public because they need to be updatable by the stats
+    CounterMoveHistory    counterMoves;
+    ButterflyHistory      mainHistory;
+    CapturePieceToHistory captureHistory;
+    ContinuationHistory   continuationHistory[2][2];
+    PawnHistory           pawnHistory;
+    CorrectionHistory     correctionHistory;
+
+   private:
+    void iterative_deepening();
+
+    // Main search function for both PV and non-PV nodes
+    template<NodeType nodeType>
+    Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, bool cutNode);
+
+    // Quiescence search function, which is called by the main search
+    template<NodeType nodeType>
+    Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth = 0);
+
+    Depth reduction(bool i, Depth d, int mn, int delta);
+
+    // Get a pointer to the search manager, only allowed to be called by the
+    // main thread.
+    SearchManager* main_manager() const {
+        assert(thread_idx == 0);
+        return static_cast<SearchManager*>(manager.get());
+    }
+
+    std::array<std::array<uint64_t, SQUARE_NB>, SQUARE_NB> effort;
+
+    LimitsType limits;
+
+    size_t                pvIdx, pvLast;
+    std::atomic<uint64_t> nodes, tbHits, bestMoveChanges;
+    int                   selDepth, nmpMinPly;
+
+    Value optimism[COLOR_NB];
+
+    Position  rootPos;
+    StateInfo rootState;
+    RootMoves rootMoves;
+    Depth     rootDepth, completedDepth;
+    Value     rootDelta;
+
+    size_t thread_idx;
+
+    // Reductions lookup table initialized at startup
+    std::array<int, MAX_MOVES> reductions;  // [depth or moveNumber]
+
+    // The main thread has a SearchManager, the others have a NullSearchManager
+    std::unique_ptr<ISearchManager> manager;
+
+    Tablebases::Config tbConfig;
+
+    const OptionsMap&   options;
+    ThreadPool&         threads;
+    TranspositionTable& tt;
+
+    friend class Stockfish::ThreadPool;
+    friend class SearchManager;
+};
+
+
+}  // namespace Search
+
+}  // namespace Stockfish
+
+#endif  // #ifndef SEARCH_H_INCLUDED

src/syzygy/tbprobe.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,58 +19,57 @@
 #ifndef TBPROBE_H
 #define TBPROBE_H
 
-#include <ostream>
+#include <string>
+#include <vector>
 
-#include "../search.h"
+
+namespace Stockfish {
+class Position;
+class OptionsMap;
+
+using Depth = int;
+
+namespace Search {
+struct RootMove;
+using RootMoves = std::vector<RootMove>;
+}
+}
 
 namespace Stockfish::Tablebases {
 
+struct Config {
+    int   cardinality = 0;
+    bool  rootInTB    = false;
+    bool  useRule50   = false;
+    Depth probeDepth  = 0;
+};
+
 enum WDLScore {
-    WDLLoss        = -2, // Loss
-    WDLBlessedLoss = -1, // Loss, but draw under 50-move rule
-    WDLDraw        =  0, // Draw
-    WDLCursedWin   =  1, // Win, but draw under 50-move rule
-    WDLWin         =  2, // Win
+    WDLLoss        = -2,  // Loss
+    WDLBlessedLoss = -1,  // Loss, but draw under 50-move rule
+    WDLDraw        = 0,   // Draw
+    WDLCursedWin   = 1,   // Win, but draw under 50-move rule
+    WDLWin         = 2,   // Win
 };
 
 // Possible states after a probing operation
 enum ProbeState {
-    FAIL              =  0, // Probe failed (missing file table)
-    OK                =  1, // Probe successful
-    CHANGE_STM        = -1, // DTZ should check the other side
-    ZEROING_BEST_MOVE =  2  // Best move zeroes DTZ (capture or pawn move)
+    FAIL              = 0,   // Probe failed (missing file table)
+    OK                = 1,   // Probe successful
+    CHANGE_STM        = -1,  // DTZ should check the other side
+    ZEROING_BEST_MOVE = 2    // Best move zeroes DTZ (capture or pawn move)
 };
 
 extern int MaxCardinality;
 
-void init(const std::string& paths);
+
+void     init(const std::string& paths);
 WDLScore probe_wdl(Position& pos, ProbeState* result);
-int probe_dtz(Position& pos, ProbeState* result);
-bool root_probe(Position& pos, Search::RootMoves& rootMoves);
-bool root_probe_wdl(Position& pos, Search::RootMoves& rootMoves);
-void rank_root_moves(Position& pos, Search::RootMoves& rootMoves);
+int      probe_dtz(Position& pos, ProbeState* result);
+bool     root_probe(Position& pos, Search::RootMoves& rootMoves, bool rule50);
+bool     root_probe_wdl(Position& pos, Search::RootMoves& rootMoves, bool rule50);
+Config   rank_root_moves(const OptionsMap& options, Position& pos, Search::RootMoves& rootMoves);
 
-inline std::ostream& operator<<(std::ostream& os, const WDLScore v) {
-
-    os << (v == WDLLoss        ? "Loss" :
-           v == WDLBlessedLoss ? "Blessed loss" :
-           v == WDLDraw        ? "Draw" :
-           v == WDLCursedWin   ? "Cursed win" :
-           v == WDLWin         ? "Win" : "None");
-
-    return os;
-}
-
-inline std::ostream& operator<<(std::ostream& os, const ProbeState v) {
-
-    os << (v == FAIL              ? "Failed" :
-           v == OK                ? "Success" :
-           v == CHANGE_STM        ? "Probed opponent side" :
-           v == ZEROING_BEST_MOVE ? "Best move zeroes DTZ" : "None");
-
-    return os;
-}
-
-} // namespace Stockfish::Tablebases
+}  // namespace Stockfish::Tablebases
 
 #endif

src/thread.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,238 +16,269 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <cassert>
+#include "thread.h"
 
-#include <algorithm> // For std::count
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <memory>
+#include <unordered_map>
+#include <utility>
+#include <array>
+
+#include "misc.h"
 #include "movegen.h"
 #include "search.h"
-#include "thread.h"
-#include "uci.h"
 #include "syzygy/tbprobe.h"
+#include "timeman.h"
 #include "tt.h"
+#include "types.h"
+#include "ucioption.h"
 
 namespace Stockfish {
 
-ThreadPool Threads; // Global object
+// Constructor launches the thread and waits until it goes to sleep
+// in idle_loop(). Note that 'searching' and 'exit' should be already set.
+Thread::Thread(Search::SharedState&                    sharedState,
+               std::unique_ptr<Search::ISearchManager> sm,
+               size_t                                  n) :
+    worker(std::make_unique<Search::Worker>(sharedState, std::move(sm), n)),
+    idx(n),
+    nthreads(sharedState.options["Threads"]),
+    stdThread(&Thread::idle_loop, this) {
 
-
-/// Thread constructor launches the thread and waits until it goes to sleep
-/// in idle_loop(). Note that 'searching' and 'exit' should be already set.
-
-Thread::Thread(size_t n) : idx(n), stdThread(&Thread::idle_loop, this) {
-
-  wait_for_search_finished();
+    wait_for_search_finished();
 }
 
 
-/// Thread destructor wakes up the thread in idle_loop() and waits
-/// for its termination. Thread should be already waiting.
-
+// Destructor wakes up the thread in idle_loop() and waits
+// for its termination. Thread should be already waiting.
 Thread::~Thread() {
 
-  assert(!searching);
+    assert(!searching);
 
-  exit = true;
-  start_searching();
-  stdThread.join();
+    exit = true;
+    start_searching();
+    stdThread.join();
 }
 
-
-/// Thread::clear() reset histories, usually before a new game
-
-void Thread::clear() {
-
-  counterMoves.fill(MOVE_NONE);
-  mainHistory.fill(0);
-  captureHistory.fill(0);
-
-  for (bool inCheck : { false, true })
-      for (StatsType c : { NoCaptures, Captures })
-          for (auto& to : continuationHistory[inCheck][c])
-              for (auto& h : to)
-                  h->fill(-71);
-}
-
-
-/// Thread::start_searching() wakes up the thread that will start the search
-
+// Wakes up the thread that will start the search
 void Thread::start_searching() {
-  mutex.lock();
-  searching = true;
-  mutex.unlock(); // Unlock before notifying saves a few CPU-cycles
-  cv.notify_one(); // Wake up the thread in idle_loop()
+    mutex.lock();
+    searching = true;
+    mutex.unlock();   // Unlock before notifying saves a few CPU-cycles
+    cv.notify_one();  // Wake up the thread in idle_loop()
 }
 
 
-/// Thread::wait_for_search_finished() blocks on the condition variable
-/// until the thread has finished searching.
-
+// Blocks on the condition variable
+// until the thread has finished searching.
 void Thread::wait_for_search_finished() {
 
-  std::unique_lock<std::mutex> lk(mutex);
-  cv.wait(lk, [&]{ return !searching; });
+    std::unique_lock<std::mutex> lk(mutex);
+    cv.wait(lk, [&] { return !searching; });
 }
 
 
-/// Thread::idle_loop() is where the thread is parked, blocked on the
-/// condition variable, when it has no work to do.
+// Thread gets parked here, blocked on the
+// condition variable, when it has no work to do.
 
 void Thread::idle_loop() {
 
-  // If OS already scheduled us on a different group than 0 then don't overwrite
-  // the choice, eventually we are one of many one-threaded processes running on
-  // some Windows NUMA hardware, for instance in fishtest. To make it simple,
-  // just check if running threads are below a threshold, in this case all this
-  // NUMA machinery is not needed.
-  if (Options["Threads"] > 8)
-      WinProcGroup::bindThisThread(idx);
+    // If OS already scheduled us on a different group than 0 then don't overwrite
+    // the choice, eventually we are one of many one-threaded processes running on
+    // some Windows NUMA hardware, for instance in fishtest. To make it simple,
+    // just check if running threads are below a threshold, in this case, all this
+    // NUMA machinery is not needed.
+    if (nthreads > 8)
+        WinProcGroup::bindThisThread(idx);
 
-  while (true)
-  {
-      std::unique_lock<std::mutex> lk(mutex);
-      searching = false;
-      cv.notify_one(); // Wake up anyone waiting for search finished
-      cv.wait(lk, [&]{ return searching; });
+    while (true)
+    {
+        std::unique_lock<std::mutex> lk(mutex);
+        searching = false;
+        cv.notify_one();  // Wake up anyone waiting for search finished
+        cv.wait(lk, [&] { return searching; });
 
-      if (exit)
-          return;
+        if (exit)
+            return;
 
-      lk.unlock();
+        lk.unlock();
 
-      search();
-  }
+        worker->start_searching();
+    }
 }
 
-/// ThreadPool::set() creates/destroys threads to match the requested number.
-/// Created and launched threads will immediately go to sleep in idle_loop.
-/// Upon resizing, threads are recreated to allow for binding if necessary.
+// Creates/destroys threads to match the requested number.
+// Created and launched threads will immediately go to sleep in idle_loop.
+// Upon resizing, threads are recreated to allow for binding if necessary.
+void ThreadPool::set(Search::SharedState sharedState) {
 
-void ThreadPool::set(size_t requested) {
+    if (threads.size() > 0)  // destroy any existing thread(s)
+    {
+        main_thread()->wait_for_search_finished();
 
-  if (threads.size() > 0)   // destroy any existing thread(s)
-  {
-      main()->wait_for_search_finished();
+        while (threads.size() > 0)
+            delete threads.back(), threads.pop_back();
+    }
 
-      while (threads.size() > 0)
-          delete threads.back(), threads.pop_back();
-  }
+    const size_t requested = sharedState.options["Threads"];
 
-  if (requested > 0)   // create new thread(s)
-  {
-      threads.push_back(new MainThread(0));
+    if (requested > 0)  // create new thread(s)
+    {
+        threads.push_back(new Thread(
+          sharedState, std::unique_ptr<Search::ISearchManager>(new Search::SearchManager()), 0));
 
-      while (threads.size() < requested)
-          threads.push_back(new Thread(threads.size()));
-      clear();
 
-      // Reallocate the hash with the new threadpool size
-      TT.resize(size_t(Options["Hash"]));
+        while (threads.size() < requested)
+            threads.push_back(new Thread(
+              sharedState, std::unique_ptr<Search::ISearchManager>(new Search::NullSearchManager()),
+              threads.size()));
+        clear();
 
-      // Init thread number dependent search params.
-      Search::init();
-  }
+        main_thread()->wait_for_search_finished();
+
+        // Reallocate the hash with the new threadpool size
+        sharedState.tt.resize(sharedState.options["Hash"], requested);
+    }
 }
 
 
-/// ThreadPool::clear() sets threadPool data to initial values
-
+// Sets threadPool data to initial values
 void ThreadPool::clear() {
 
-  for (Thread* th : threads)
-      th->clear();
+    for (Thread* th : threads)
+        th->worker->clear();
 
-  main()->callsCnt = 0;
-  main()->bestPreviousScore = VALUE_INFINITE;
-  main()->bestPreviousAverageScore = VALUE_INFINITE;
-  main()->previousTimeReduction = 1.0;
+    main_manager()->callsCnt                 = 0;
+    main_manager()->bestPreviousScore        = VALUE_INFINITE;
+    main_manager()->bestPreviousAverageScore = VALUE_INFINITE;
+    main_manager()->previousTimeReduction    = 1.0;
+    main_manager()->tm.clear();
 }
 
 
-/// ThreadPool::start_thinking() wakes up main thread waiting in idle_loop() and
-/// returns immediately. Main thread will wake up other threads and start the search.
+// Wakes up main thread waiting in idle_loop() and
+// returns immediately. Main thread will wake up other threads and start the search.
+void ThreadPool::start_thinking(const OptionsMap&  options,
+                                Position&          pos,
+                                StateListPtr&      states,
+                                Search::LimitsType limits,
+                                bool               ponderMode) {
 
-void ThreadPool::start_thinking(Position& pos, StateListPtr& states,
-                                const Search::LimitsType& limits, bool ponderMode) {
+    main_thread()->wait_for_search_finished();
 
-  main()->wait_for_search_finished();
+    main_manager()->stopOnPonderhit = stop = abortedSearch = false;
+    main_manager()->ponder                                 = ponderMode;
 
-  main()->stopOnPonderhit = stop = false;
-  increaseDepth = true;
-  main()->ponder = ponderMode;
-  Search::Limits = limits;
-  Search::RootMoves rootMoves;
+    increaseDepth = true;
 
-  for (const auto& m : MoveList<LEGAL>(pos))
-      if (   limits.searchmoves.empty()
-          || std::count(limits.searchmoves.begin(), limits.searchmoves.end(), m))
-          rootMoves.emplace_back(m);
+    Search::RootMoves rootMoves;
 
-  if (!rootMoves.empty())
-      Tablebases::rank_root_moves(pos, rootMoves);
+    for (const auto& m : MoveList<LEGAL>(pos))
+        if (limits.searchmoves.empty()
+            || std::count(limits.searchmoves.begin(), limits.searchmoves.end(), m))
+            rootMoves.emplace_back(m);
 
-  // After ownership transfer 'states' becomes empty, so if we stop the search
-  // and call 'go' again without setting a new position states.get() == nullptr.
-  assert(states.get() || setupStates.get());
+    Tablebases::Config tbConfig = Tablebases::rank_root_moves(options, pos, rootMoves);
 
-  if (states.get())
-      setupStates = std::move(states); // Ownership transfer, states is now empty
+    // After ownership transfer 'states' becomes empty, so if we stop the search
+    // and call 'go' again without setting a new position states.get() == nullptr.
+    assert(states.get() || setupStates.get());
 
-  // We use Position::set() to set root position across threads. But there are
-  // some StateInfo fields (previous, pliesFromNull, capturedPiece) that cannot
-  // be deduced from a fen string, so set() clears them and they are set from
-  // setupStates->back() later. The rootState is per thread, earlier states are shared
-  // since they are read-only.
-  for (Thread* th : threads)
-  {
-      th->nodes = th->tbHits = th->nmpMinPly = th->bestMoveChanges = 0;
-      th->rootDepth = th->completedDepth = 0;
-      th->rootMoves = rootMoves;
-      th->rootPos.set(pos.fen(), pos.is_chess960(), &th->rootState, th);
-      th->rootState = setupStates->back();
-  }
+    if (states.get())
+        setupStates = std::move(states);  // Ownership transfer, states is now empty
 
-  main()->start_searching();
+    // We use Position::set() to set root position across threads. But there are
+    // some StateInfo fields (previous, pliesFromNull, capturedPiece) that cannot
+    // be deduced from a fen string, so set() clears them and they are set from
+    // setupStates->back() later. The rootState is per thread, earlier states are shared
+    // since they are read-only.
+    for (Thread* th : threads)
+    {
+        th->worker->limits = limits;
+        th->worker->nodes = th->worker->tbHits = th->worker->nmpMinPly =
+          th->worker->bestMoveChanges          = 0;
+        th->worker->rootDepth = th->worker->completedDepth = 0;
+        th->worker->rootMoves                              = rootMoves;
+        th->worker->rootPos.set(pos.fen(), pos.is_chess960(), &th->worker->rootState);
+        th->worker->rootState = setupStates->back();
+        th->worker->tbConfig  = tbConfig;
+        th->worker->effort    = {};
+    }
+
+    main_thread()->start_searching();
 }
 
 Thread* ThreadPool::get_best_thread() const {
 
     Thread* bestThread = threads.front();
-    std::map<Move, int64_t> votes;
-    Value minScore = VALUE_NONE;
+    Value   minScore   = VALUE_NONE;
 
-    // Find minimum score of all threads
-    for (Thread* th: threads)
-        minScore = std::min(minScore, th->rootMoves[0].score);
+    std::unordered_map<Move, int64_t, Move::MoveHash> votes(
+      2 * std::min(size(), bestThread->worker->rootMoves.size()));
+
+    // Find the minimum score of all threads
+    for (Thread* th : threads)
+        minScore = std::min(minScore, th->worker->rootMoves[0].score);
 
     // Vote according to score and depth, and select the best thread
-    auto thread_value = [minScore](Thread* th) {
-            return (th->rootMoves[0].score - minScore + 14) * int(th->completedDepth);
-        };
+    auto thread_voting_value = [minScore](Thread* th) {
+        return (th->worker->rootMoves[0].score - minScore + 14) * int(th->worker->completedDepth);
+    };
 
     for (Thread* th : threads)
-        votes[th->rootMoves[0].pv[0]] += thread_value(th);
+        votes[th->worker->rootMoves[0].pv[0]] += thread_voting_value(th);
 
     for (Thread* th : threads)
-        if (abs(bestThread->rootMoves[0].score) >= VALUE_TB_WIN_IN_MAX_PLY)
+    {
+        const auto bestThreadScore = bestThread->worker->rootMoves[0].score;
+        const auto newThreadScore  = th->worker->rootMoves[0].score;
+
+        const auto& bestThreadPV = bestThread->worker->rootMoves[0].pv;
+        const auto& newThreadPV  = th->worker->rootMoves[0].pv;
+
+        const auto bestThreadMoveVote = votes[bestThreadPV[0]];
+        const auto newThreadMoveVote  = votes[newThreadPV[0]];
+
+        const bool bestThreadInProvenWin = bestThreadScore >= VALUE_TB_WIN_IN_MAX_PLY;
+        const bool newThreadInProvenWin  = newThreadScore >= VALUE_TB_WIN_IN_MAX_PLY;
+
+        const bool bestThreadInProvenLoss =
+          bestThreadScore != -VALUE_INFINITE && bestThreadScore <= VALUE_TB_LOSS_IN_MAX_PLY;
+        const bool newThreadInProvenLoss =
+          newThreadScore != -VALUE_INFINITE && newThreadScore <= VALUE_TB_LOSS_IN_MAX_PLY;
+
+        // Note that we make sure not to pick a thread with truncated-PV for better viewer experience.
+        const bool betterVotingValue =
+          thread_voting_value(th) * int(newThreadPV.size() > 2)
+          > thread_voting_value(bestThread) * int(bestThreadPV.size() > 2);
+
+        if (bestThreadInProvenWin)
         {
-            // Make sure we pick the shortest mate / TB conversion or stave off mate the longest
-            if (th->rootMoves[0].score > bestThread->rootMoves[0].score)
+            // Make sure we pick the shortest mate / TB conversion
+            if (newThreadScore > bestThreadScore)
                 bestThread = th;
         }
-        else if (   th->rootMoves[0].score >= VALUE_TB_WIN_IN_MAX_PLY
-                 || (   th->rootMoves[0].score > VALUE_TB_LOSS_IN_MAX_PLY
-                     && (   votes[th->rootMoves[0].pv[0]] > votes[bestThread->rootMoves[0].pv[0]]
-                         || (   votes[th->rootMoves[0].pv[0]] == votes[bestThread->rootMoves[0].pv[0]]
-                             &&   thread_value(th) * int(th->rootMoves[0].pv.size() > 2)
-                                > thread_value(bestThread) * int(bestThread->rootMoves[0].pv.size() > 2)))))
+        else if (bestThreadInProvenLoss)
+        {
+            // Make sure we pick the shortest mated / TB conversion
+            if (newThreadInProvenLoss && newThreadScore < bestThreadScore)
+                bestThread = th;
+        }
+        else if (newThreadInProvenWin || newThreadInProvenLoss
+                 || (newThreadScore > VALUE_TB_LOSS_IN_MAX_PLY
+                     && (newThreadMoveVote > bestThreadMoveVote
+                         || (newThreadMoveVote == bestThreadMoveVote && betterVotingValue))))
             bestThread = th;
+    }
 
     return bestThread;
 }
 
 
-/// Start non-main threads
-
+// Start non-main threads
+// Will be invoked by main thread after it has started searching
 void ThreadPool::start_searching() {
 
     for (Thread* th : threads)
@@ -256,7 +287,7 @@ void ThreadPool::start_searching() {
 }
 
 
-/// Wait for non-main threads
+// Wait for non-main threads
 
 void ThreadPool::wait_for_search_finished() const {
 
@@ -265,4 +296,4 @@ void ThreadPool::wait_for_search_finished() const {
             th->wait_for_search_finished();
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/thread.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,121 +21,101 @@
 
 #include <atomic>
 #include <condition_variable>
+#include <cstddef>
+#include <cstdint>
+#include <memory>
 #include <mutex>
-#include <thread>
 #include <vector>
 
-#include "material.h"
-#include "movepick.h"
-#include "pawns.h"
 #include "position.h"
 #include "search.h"
 #include "thread_win32_osx.h"
 
 namespace Stockfish {
 
-/// Thread class keeps together all the thread-related stuff. We use
-/// per-thread pawn and material hash tables so that once we get a
-/// pointer to an entry its life time is unlimited and we don't have
-/// to care about someone changing the entry under our feet.
+class OptionsMap;
+using Value = int;
 
+// Abstraction of a thread. It contains a pointer to the worker and a native thread.
+// After construction, the native thread is started with idle_loop()
+// waiting for a signal to start searching.
+// When the signal is received, the thread starts searching and when
+// the search is finished, it goes back to idle_loop() waiting for a new signal.
 class Thread {
+   public:
+    Thread(Search::SharedState&, std::unique_ptr<Search::ISearchManager>, size_t);
+    virtual ~Thread();
 
-  std::mutex mutex;
-  std::condition_variable cv;
-  size_t idx;
-  bool exit = false, searching = true; // Set before starting std::thread
-  NativeThread stdThread;
+    void   idle_loop();
+    void   start_searching();
+    void   wait_for_search_finished();
+    size_t id() const { return idx; }
 
-public:
-  explicit Thread(size_t);
-  virtual ~Thread();
-  virtual void search();
-  void clear();
-  void idle_loop();
-  void start_searching();
-  void wait_for_search_finished();
-  size_t id() const { return idx; }
+    std::unique_ptr<Search::Worker> worker;
 
-  Pawns::Table pawnsTable;
-  Material::Table materialTable;
-  size_t pvIdx, pvLast;
-  std::atomic<uint64_t> nodes, tbHits, bestMoveChanges;
-  int selDepth, nmpMinPly;
-  Value bestValue, optimism[COLOR_NB];
-
-  Position rootPos;
-  StateInfo rootState;
-  Search::RootMoves rootMoves;
-  Depth rootDepth, completedDepth;
-  Value rootDelta;
-  CounterMoveHistory counterMoves;
-  ButterflyHistory mainHistory;
-  CapturePieceToHistory captureHistory;
-  ContinuationHistory continuationHistory[2][2];
+   private:
+    std::mutex              mutex;
+    std::condition_variable cv;
+    size_t                  idx, nthreads;
+    bool                    exit = false, searching = true;  // Set before starting std::thread
+    NativeThread            stdThread;
 };
 
 
-/// MainThread is a derived class specific for main thread
+// ThreadPool struct handles all the threads-related stuff like init, starting,
+// parking and, most importantly, launching a thread. All the access to threads
+// is done through this class.
+class ThreadPool {
 
-struct MainThread : public Thread {
+   public:
+    ~ThreadPool() {
+        // destroy any existing thread(s)
+        if (threads.size() > 0)
+        {
+            main_thread()->wait_for_search_finished();
 
-  using Thread::Thread;
+            while (threads.size() > 0)
+                delete threads.back(), threads.pop_back();
+        }
+    }
 
-  void search() override;
-  void check_time();
+    void
+    start_thinking(const OptionsMap&, Position&, StateListPtr&, Search::LimitsType, bool = false);
+    void clear();
+    void set(Search::SharedState);
 
-  double previousTimeReduction;
-  Value bestPreviousScore;
-  Value bestPreviousAverageScore;
-  Value iterValue[4];
-  int callsCnt;
-  bool stopOnPonderhit;
-  std::atomic_bool ponder;
+    Search::SearchManager* main_manager() const {
+        return static_cast<Search::SearchManager*>(main_thread()->worker.get()->manager.get());
+    };
+    Thread*  main_thread() const { return threads.front(); }
+    uint64_t nodes_searched() const { return accumulate(&Search::Worker::nodes); }
+    uint64_t tb_hits() const { return accumulate(&Search::Worker::tbHits); }
+    Thread*  get_best_thread() const;
+    void     start_searching();
+    void     wait_for_search_finished() const;
+
+    std::atomic_bool stop, abortedSearch, increaseDepth;
+
+    auto cbegin() const noexcept { return threads.cbegin(); }
+    auto begin() noexcept { return threads.begin(); }
+    auto end() noexcept { return threads.end(); }
+    auto cend() const noexcept { return threads.cend(); }
+    auto size() const noexcept { return threads.size(); }
+    auto empty() const noexcept { return threads.empty(); }
+
+   private:
+    StateListPtr         setupStates;
+    std::vector<Thread*> threads;
+
+    uint64_t accumulate(std::atomic<uint64_t> Search::Worker::*member) const {
+
+        uint64_t sum = 0;
+        for (Thread* th : threads)
+            sum += (th->worker.get()->*member).load(std::memory_order_relaxed);
+        return sum;
+    }
 };
 
+}  // namespace Stockfish
 
-/// ThreadPool struct handles all the threads-related stuff like init, starting,
-/// parking and, most importantly, launching a thread. All the access to threads
-/// is done through this class.
-
-struct ThreadPool {
-
-  void start_thinking(Position&, StateListPtr&, const Search::LimitsType&, bool = false);
-  void clear();
-  void set(size_t);
-
-  MainThread* main()        const { return static_cast<MainThread*>(threads.front()); }
-  uint64_t nodes_searched() const { return accumulate(&Thread::nodes); }
-  uint64_t tb_hits()        const { return accumulate(&Thread::tbHits); }
-  Thread* get_best_thread() const;
-  void start_searching();
-  void wait_for_search_finished() const;
-
-  std::atomic_bool stop, increaseDepth;
-
-  auto cbegin() const noexcept { return threads.cbegin(); }
-  auto begin() noexcept { return threads.begin(); }
-  auto end() noexcept { return threads.end(); }
-  auto cend() const noexcept { return threads.cend(); }
-  auto size() const noexcept { return threads.size(); }
-  auto empty() const noexcept { return threads.empty(); }
-
-private:
-  StateListPtr setupStates;
-  std::vector<Thread*> threads;
-
-  uint64_t accumulate(std::atomic<uint64_t> Thread::* member) const {
-
-    uint64_t sum = 0;
-    for (Thread* th : threads)
-        sum += (th->*member).load(std::memory_order_relaxed);
-    return sum;
-  }
-};
-
-extern ThreadPool Threads;
-
-} // namespace Stockfish
-
-#endif // #ifndef THREAD_H_INCLUDED
+#endif  // #ifndef THREAD_H_INCLUDED

src/thread_win32_osx.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,54 +21,58 @@
 
 #include <thread>
 
-/// On OSX threads other than the main thread are created with a reduced stack
-/// size of 512KB by default, this is too low for deep searches, which require
-/// somewhat more than 1MB stack, so adjust it to TH_STACK_SIZE.
-/// The implementation calls pthread_create() with the stack size parameter
-/// equal to the linux 8MB default, on platforms that support it.
+// On OSX threads other than the main thread are created with a reduced stack
+// size of 512KB by default, this is too low for deep searches, which require
+// somewhat more than 1MB stack, so adjust it to TH_STACK_SIZE.
+// The implementation calls pthread_create() with the stack size parameter
+// equal to the Linux 8MB default, on platforms that support it.
 
 #if defined(__APPLE__) || defined(__MINGW32__) || defined(__MINGW64__) || defined(USE_PTHREADS)
 
-#include <pthread.h>
+    #include <pthread.h>
+    #include <functional>
 
 namespace Stockfish {
 
-static const size_t TH_STACK_SIZE = 8 * 1024 * 1024;
-
-template <class T, class P = std::pair<T*, void(T::*)()>>
-void* start_routine(void* ptr)
-{
-   P* p = reinterpret_cast<P*>(ptr);
-   (p->first->*(p->second))(); // Call member function pointer
-   delete p;
-   return nullptr;
-}
-
 class NativeThread {
+    pthread_t thread;
 
-   pthread_t thread;
+    static constexpr size_t TH_STACK_SIZE = 8 * 1024 * 1024;
 
-public:
-  template<class T, class P = std::pair<T*, void(T::*)()>>
-  explicit NativeThread(void(T::*fun)(), T* obj) {
-    pthread_attr_t attr_storage, *attr = &attr_storage;
-    pthread_attr_init(attr);
-    pthread_attr_setstacksize(attr, TH_STACK_SIZE);
-    pthread_create(&thread, attr, start_routine<T>, new P(obj, fun));
-  }
-  void join() { pthread_join(thread, nullptr); }
+   public:
+    template<class Function, class... Args>
+    explicit NativeThread(Function&& fun, Args&&... args) {
+        auto func = new std::function<void()>(
+          std::bind(std::forward<Function>(fun), std::forward<Args>(args)...));
+
+        pthread_attr_t attr_storage, *attr = &attr_storage;
+        pthread_attr_init(attr);
+        pthread_attr_setstacksize(attr, TH_STACK_SIZE);
+
+        auto start_routine = [](void* ptr) -> void* {
+            auto f = reinterpret_cast<std::function<void()>*>(ptr);
+            // Call the function
+            (*f)();
+            delete f;
+            return nullptr;
+        };
+
+        pthread_create(&thread, attr, start_routine, func);
+    }
+
+    void join() { pthread_join(thread, nullptr); }
 };
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#else // Default case: use STL classes
+#else  // Default case: use STL classes
 
 namespace Stockfish {
 
 using NativeThread = std::thread;
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
 #endif
 
-#endif // #ifndef THREAD_WIN32_OSX_H_INCLUDED
+#endif  // #ifndef THREAD_WIN32_OSX_H_INCLUDED

src/timeman.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,94 +16,111 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "timeman.h"
+
 #include <algorithm>
-#include <cfloat>
+#include <cassert>
 #include <cmath>
+#include <cstdint>
 
 #include "search.h"
-#include "timeman.h"
-#include "uci.h"
+#include "ucioption.h"
 
 namespace Stockfish {
 
-TimeManagement Time; // Our global time management object
-
-
-/// TimeManagement::init() is called at the beginning of the search and calculates
-/// the bounds of time allowed for the current game ply. We currently support:
-//      1) x basetime (+ z increment)
-//      2) x moves in y seconds (+ z increment)
-
-void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
-
-  // if we have no time, no need to initialize TM, except for the start time,
-  // which is used by movetime.
-  startTime = limits.startTime;
-  if (limits.time[us] == 0)
-      return;
-
-  TimePoint moveOverhead    = TimePoint(Options["Move Overhead"]);
-  TimePoint slowMover       = TimePoint(Options["Slow Mover"]);
-  TimePoint npmsec          = TimePoint(Options["nodestime"]);
-
-  // optScale is a percentage of available time to use for the current move.
-  // maxScale is a multiplier applied to optimumTime.
-  double optScale, maxScale;
-
-  // If we have to play in 'nodes as time' mode, then convert from time
-  // to nodes, and use resulting values in time management formulas.
-  // WARNING: to avoid time losses, the given npmsec (nodes per millisecond)
-  // must be much lower than the real engine speed.
-  if (npmsec)
-  {
-      if (!availableNodes) // Only once at game start
-          availableNodes = npmsec * limits.time[us]; // Time is in msec
-
-      // Convert from milliseconds to nodes
-      limits.time[us] = TimePoint(availableNodes);
-      limits.inc[us] *= npmsec;
-      limits.npmsec = npmsec;
-  }
-
-  // Maximum move horizon of 50 moves
-  int mtg = limits.movestogo ? std::min(limits.movestogo, 50) : 50;
-
-  // Make sure timeLeft is > 0 since we may use it as a divisor
-  TimePoint timeLeft =  std::max(TimePoint(1),
-      limits.time[us] + limits.inc[us] * (mtg - 1) - moveOverhead * (2 + mtg));
-
-  // Use extra time with larger increments
-  double optExtra = std::clamp(1.0 + 12.0 * limits.inc[us] / limits.time[us], 1.0, 1.12);
-
-  // A user may scale time usage by setting UCI option "Slow Mover"
-  // Default is 100 and changing this value will probably lose elo.
-  timeLeft = slowMover * timeLeft / 100;
-
-  // x basetime (+ z increment)
-  // If there is a healthy increment, timeLeft can exceed actual available
-  // game time for the current move, so also cap to 20% of available game time.
-  if (limits.movestogo == 0)
-  {
-      optScale = std::min(0.0120 + std::pow(ply + 3.0, 0.45) * 0.0039,
-                           0.2 * limits.time[us] / double(timeLeft))
-                 * optExtra;
-      maxScale = std::min(7.0, 4.0 + ply / 12.0);
-  }
-
-  // x moves in y seconds (+ z increment)
-  else
-  {
-      optScale = std::min((0.88 + ply / 116.4) / mtg,
-                            0.88 * limits.time[us] / double(timeLeft));
-      maxScale = std::min(6.3, 1.5 + 0.11 * mtg);
-  }
-
-  // Never use more than 80% of the available time for this move
-  optimumTime = TimePoint(optScale * timeLeft);
-  maximumTime = TimePoint(std::min(0.8 * limits.time[us] - moveOverhead, maxScale * optimumTime));
-
-  if (Options["Ponder"])
-      optimumTime += optimumTime / 4;
+TimePoint TimeManagement::optimum() const { return optimumTime; }
+TimePoint TimeManagement::maximum() const { return maximumTime; }
+TimePoint TimeManagement::elapsed(size_t nodes) const {
+    return useNodesTime ? TimePoint(nodes) : now() - startTime;
 }
 
-} // namespace Stockfish
+void TimeManagement::clear() {
+    availableNodes = 0;  // When in 'nodes as time' mode
+}
+
+void TimeManagement::advance_nodes_time(std::int64_t nodes) {
+    assert(useNodesTime);
+    availableNodes += nodes;
+}
+
+// Called at the beginning of the search and calculates
+// the bounds of time allowed for the current game ply. We currently support:
+//      1) x basetime (+ z increment)
+//      2) x moves in y seconds (+ z increment)
+void TimeManagement::init(Search::LimitsType& limits,
+                          Color               us,
+                          int                 ply,
+                          const OptionsMap&   options) {
+    // If we have no time, no need to initialize TM, except for the start time,
+    // which is used by movetime.
+    startTime = limits.startTime;
+    if (limits.time[us] == 0)
+        return;
+
+    TimePoint moveOverhead = TimePoint(options["Move Overhead"]);
+    TimePoint npmsec       = TimePoint(options["nodestime"]);
+
+    // optScale is a percentage of available time to use for the current move.
+    // maxScale is a multiplier applied to optimumTime.
+    double optScale, maxScale;
+
+    // If we have to play in 'nodes as time' mode, then convert from time
+    // to nodes, and use resulting values in time management formulas.
+    // WARNING: to avoid time losses, the given npmsec (nodes per millisecond)
+    // must be much lower than the real engine speed.
+    if (npmsec)
+    {
+        useNodesTime = true;
+
+        if (!availableNodes)                            // Only once at game start
+            availableNodes = npmsec * limits.time[us];  // Time is in msec
+
+        // Convert from milliseconds to nodes
+        limits.time[us] = TimePoint(availableNodes);
+        limits.inc[us] *= npmsec;
+        limits.npmsec = npmsec;
+    }
+
+    // Maximum move horizon of 50 moves
+    int mtg = limits.movestogo ? std::min(limits.movestogo, 50) : 50;
+
+    // Make sure timeLeft is > 0 since we may use it as a divisor
+    TimePoint timeLeft = std::max(TimePoint(1), limits.time[us] + limits.inc[us] * (mtg - 1)
+                                                  - moveOverhead * (2 + mtg));
+
+    // x basetime (+ z increment)
+    // If there is a healthy increment, timeLeft can exceed actual available
+    // game time for the current move, so also cap to 20% of available game time.
+    if (limits.movestogo == 0)
+    {
+        // Use extra time with larger increments
+        double optExtra = std::clamp(1.0 + 12.5 * limits.inc[us] / limits.time[us], 1.0, 1.11);
+
+        // Calculate time constants based on current time left.
+        double optConstant =
+          std::min(0.00334 + 0.0003 * std::log10(limits.time[us] / 1000.0), 0.0049);
+        double maxConstant = std::max(3.4 + 3.0 * std::log10(limits.time[us] / 1000.0), 2.76);
+
+        optScale = std::min(0.0120 + std::pow(ply + 3.1, 0.44) * optConstant,
+                            0.21 * limits.time[us] / double(timeLeft))
+                 * optExtra;
+        maxScale = std::min(6.9, maxConstant + ply / 12.2);
+    }
+
+    // x moves in y seconds (+ z increment)
+    else
+    {
+        optScale = std::min((0.88 + ply / 116.4) / mtg, 0.88 * limits.time[us] / double(timeLeft));
+        maxScale = std::min(6.3, 1.5 + 0.11 * mtg);
+    }
+
+    // Limit the maximum possible time for this move
+    optimumTime = TimePoint(optScale * timeLeft);
+    maximumTime =
+      TimePoint(std::min(0.84 * limits.time[us] - moveOverhead, maxScale * optimumTime)) - 10;
+
+    if (options["Ponder"])
+        optimumTime += optimumTime / 4;
+}
+
+}  // namespace Stockfish

src/timeman.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,33 +19,42 @@
 #ifndef TIMEMAN_H_INCLUDED
 #define TIMEMAN_H_INCLUDED
 
+#include <cstddef>
+#include <cstdint>
+
 #include "misc.h"
-#include "search.h"
-#include "thread.h"
+#include "types.h"
 
 namespace Stockfish {
 
-/// The TimeManagement class computes the optimal time to think depending on
-/// the maximum available time, the game move number and other parameters.
+class OptionsMap;
 
+namespace Search {
+struct LimitsType;
+}
+
+// The TimeManagement class computes the optimal time to think depending on
+// the maximum available time, the game move number, and other parameters.
 class TimeManagement {
-public:
-  void init(Search::LimitsType& limits, Color us, int ply);
-  TimePoint optimum() const { return optimumTime; }
-  TimePoint maximum() const { return maximumTime; }
-  TimePoint elapsed() const { return Search::Limits.npmsec ?
-                                     TimePoint(Threads.nodes_searched()) : now() - startTime; }
+   public:
+    void init(Search::LimitsType& limits, Color us, int ply, const OptionsMap& options);
 
-  int64_t availableNodes; // When in 'nodes as time' mode
+    TimePoint optimum() const;
+    TimePoint maximum() const;
+    TimePoint elapsed(std::size_t nodes) const;
 
-private:
-  TimePoint startTime;
-  TimePoint optimumTime;
-  TimePoint maximumTime;
+    void clear();
+    void advance_nodes_time(std::int64_t nodes);
+
+   private:
+    TimePoint startTime;
+    TimePoint optimumTime;
+    TimePoint maximumTime;
+
+    std::int64_t availableNodes = 0;      // When in 'nodes as time' mode
+    bool         useNodesTime   = false;  // True if we are in 'nodes as time' mode
 };
 
-extern TimeManagement Time;
+}  // namespace Stockfish
 
-} // namespace Stockfish
-
-#endif // #ifndef TIMEMAN_H_INCLUDED
+#endif  // #ifndef TIMEMAN_H_INCLUDED

src/tt.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,147 +16,137 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <cstring>   // For std::memset
+#include "tt.h"
+
+#include <cassert>
+#include <cstdlib>
+#include <cstring>
 #include <iostream>
 #include <thread>
+#include <vector>
 
-#include "bitboard.h"
 #include "misc.h"
-#include "thread.h"
-#include "tt.h"
-#include "uci.h"
 
 namespace Stockfish {
 
-TranspositionTable TT; // Our global transposition table
+// Populates the TTEntry with a new node's data, possibly
+// overwriting an old position. The update is not atomic and can be racy.
+void TTEntry::save(
+  Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev, uint8_t generation8) {
 
-/// TTEntry::save() populates the TTEntry with a new node's data, possibly
-/// overwriting an old position. Update is not atomic and can be racy.
+    // Preserve any existing move for the same position
+    if (m || uint16_t(k) != key16)
+        move16 = m;
 
-void TTEntry::save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev) {
+    // Overwrite less valuable entries (cheapest checks first)
+    if (b == BOUND_EXACT || uint16_t(k) != key16 || d - DEPTH_OFFSET + 2 * pv > depth8 - 4)
+    {
+        assert(d > DEPTH_OFFSET);
+        assert(d < 256 + DEPTH_OFFSET);
 
-  // Preserve any existing move for the same position
-  if (m || (uint16_t)k != key16)
-      move16 = (uint16_t)m;
-
-  // Overwrite less valuable entries (cheapest checks first)
-  if (   b == BOUND_EXACT
-      || (uint16_t)k != key16
-      || d - DEPTH_OFFSET + 2 * pv > depth8 - 4)
-  {
-      assert(d > DEPTH_OFFSET);
-      assert(d < 256 + DEPTH_OFFSET);
-
-      key16     = (uint16_t)k;
-      depth8    = (uint8_t)(d - DEPTH_OFFSET);
-      genBound8 = (uint8_t)(TT.generation8 | uint8_t(pv) << 2 | b);
-      value16   = (int16_t)v;
-      eval16    = (int16_t)ev;
-  }
+        key16     = uint16_t(k);
+        depth8    = uint8_t(d - DEPTH_OFFSET);
+        genBound8 = uint8_t(generation8 | uint8_t(pv) << 2 | b);
+        value16   = int16_t(v);
+        eval16    = int16_t(ev);
+    }
 }
 
 
-/// TranspositionTable::resize() sets the size of the transposition table,
-/// measured in megabytes. Transposition table consists of a power of 2 number
-/// of clusters and each cluster consists of ClusterSize number of TTEntry.
+// Sets the size of the transposition table,
+// measured in megabytes. Transposition table consists of a power of 2 number
+// of clusters and each cluster consists of ClusterSize number of TTEntry.
+void TranspositionTable::resize(size_t mbSize, int threadCount) {
+    aligned_large_pages_free(table);
 
-void TranspositionTable::resize(size_t mbSize) {
+    clusterCount = mbSize * 1024 * 1024 / sizeof(Cluster);
 
-  Threads.main()->wait_for_search_finished();
+    table = static_cast<Cluster*>(aligned_large_pages_alloc(clusterCount * sizeof(Cluster)));
+    if (!table)
+    {
+        std::cerr << "Failed to allocate " << mbSize << "MB for transposition table." << std::endl;
+        exit(EXIT_FAILURE);
+    }
 
-  aligned_large_pages_free(table);
-
-  clusterCount = mbSize * 1024 * 1024 / sizeof(Cluster);
-
-  table = static_cast<Cluster*>(aligned_large_pages_alloc(clusterCount * sizeof(Cluster)));
-  if (!table)
-  {
-      std::cerr << "Failed to allocate " << mbSize
-                << "MB for transposition table." << std::endl;
-      exit(EXIT_FAILURE);
-  }
-
-  clear();
+    clear(threadCount);
 }
 
 
-/// TranspositionTable::clear() initializes the entire transposition table to zero,
-//  in a multi-threaded way.
+// Initializes the entire transposition table to zero,
+// in a multi-threaded way.
+void TranspositionTable::clear(size_t threadCount) {
+    std::vector<std::thread> threads;
 
-void TranspositionTable::clear() {
+    for (size_t idx = 0; idx < size_t(threadCount); ++idx)
+    {
+        threads.emplace_back([this, idx, threadCount]() {
+            // Thread binding gives faster search on systems with a first-touch policy
+            if (threadCount > 8)
+                WinProcGroup::bindThisThread(idx);
 
-  std::vector<std::thread> threads;
+            // Each thread will zero its part of the hash table
+            const size_t stride = size_t(clusterCount / threadCount), start = size_t(stride * idx),
+                         len = idx != size_t(threadCount) - 1 ? stride : clusterCount - start;
 
-  for (size_t idx = 0; idx < size_t(Options["Threads"]); ++idx)
-  {
-      threads.emplace_back([this, idx]() {
+            std::memset(&table[start], 0, len * sizeof(Cluster));
+        });
+    }
 
-          // Thread binding gives faster search on systems with a first-touch policy
-          if (Options["Threads"] > 8)
-              WinProcGroup::bindThisThread(idx);
-
-          // Each thread will zero its part of the hash table
-          const size_t stride = size_t(clusterCount / Options["Threads"]),
-                       start  = size_t(stride * idx),
-                       len    = idx != size_t(Options["Threads"]) - 1 ?
-                                stride : clusterCount - start;
-
-          std::memset(&table[start], 0, len * sizeof(Cluster));
-      });
-  }
-
-  for (std::thread& th : threads)
-      th.join();
+    for (std::thread& th : threads)
+        th.join();
 }
 
 
-/// TranspositionTable::probe() looks up the current position in the transposition
-/// table. It returns true and a pointer to the TTEntry if the position is found.
-/// Otherwise, it returns false and a pointer to an empty or least valuable TTEntry
-/// to be replaced later. The replace value of an entry is calculated as its depth
-/// minus 8 times its relative age. TTEntry t1 is considered more valuable than
-/// TTEntry t2 if its replace value is greater than that of t2.
-
+// Looks up the current position in the transposition
+// table. It returns true and a pointer to the TTEntry if the position is found.
+// Otherwise, it returns false and a pointer to an empty or least valuable TTEntry
+// to be replaced later. The replace value of an entry is calculated as its depth
+// minus 8 times its relative age. TTEntry t1 is considered more valuable than
+// TTEntry t2 if its replace value is greater than that of t2.
 TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
 
-  TTEntry* const tte = first_entry(key);
-  const uint16_t key16 = (uint16_t)key;  // Use the low 16 bits as key inside the cluster
+    TTEntry* const tte   = first_entry(key);
+    const uint16_t key16 = uint16_t(key);  // Use the low 16 bits as key inside the cluster
 
-  for (int i = 0; i < ClusterSize; ++i)
-      if (tte[i].key16 == key16 || !tte[i].depth8)
-      {
-          tte[i].genBound8 = uint8_t(generation8 | (tte[i].genBound8 & (GENERATION_DELTA - 1))); // Refresh
+    for (int i = 0; i < ClusterSize; ++i)
+        if (tte[i].key16 == key16 || !tte[i].depth8)
+        {
+            tte[i].genBound8 =
+              uint8_t(generation8 | (tte[i].genBound8 & (GENERATION_DELTA - 1)));  // Refresh
 
-          return found = (bool)tte[i].depth8, &tte[i];
-      }
+            return found = bool(tte[i].depth8), &tte[i];
+        }
 
-  // Find an entry to be replaced according to the replacement strategy
-  TTEntry* replace = tte;
-  for (int i = 1; i < ClusterSize; ++i)
-      // Due to our packed storage format for generation and its cyclic
-      // nature we add GENERATION_CYCLE (256 is the modulus, plus what
-      // is needed to keep the unrelated lowest n bits from affecting
-      // the result) to calculate the entry age correctly even after
-      // generation8 overflows into the next cycle.
-      if (  replace->depth8 - ((GENERATION_CYCLE + generation8 - replace->genBound8) & GENERATION_MASK)
-          >   tte[i].depth8 - ((GENERATION_CYCLE + generation8 -   tte[i].genBound8) & GENERATION_MASK))
-          replace = &tte[i];
+    // Find an entry to be replaced according to the replacement strategy
+    TTEntry* replace = tte;
+    for (int i = 1; i < ClusterSize; ++i)
+        // Due to our packed storage format for generation and its cyclic
+        // nature we add GENERATION_CYCLE (256 is the modulus, plus what
+        // is needed to keep the unrelated lowest n bits from affecting
+        // the result) to calculate the entry age correctly even after
+        // generation8 overflows into the next cycle.
+        if (replace->depth8
+              - ((GENERATION_CYCLE + generation8 - replace->genBound8) & GENERATION_MASK)
+            > tte[i].depth8
+                - ((GENERATION_CYCLE + generation8 - tte[i].genBound8) & GENERATION_MASK))
+            replace = &tte[i];
 
-  return found = false, replace;
+    return found = false, replace;
 }
 
 
-/// TranspositionTable::hashfull() returns an approximation of the hashtable
-/// occupation during a search. The hash is x permill full, as per UCI protocol.
+// Returns an approximation of the hashtable
+// occupation during a search. The hash is x permill full, as per UCI protocol.
 
 int TranspositionTable::hashfull() const {
 
-  int cnt = 0;
-  for (int i = 0; i < 1000; ++i)
-      for (int j = 0; j < ClusterSize; ++j)
-          cnt += table[i].entry[j].depth8 && (table[i].entry[j].genBound8 & GENERATION_MASK) == generation8;
+    int cnt = 0;
+    for (int i = 0; i < 1000; ++i)
+        for (int j = 0; j < ClusterSize; ++j)
+            cnt += table[i].entry[j].depth8
+                && (table[i].entry[j].genBound8 & GENERATION_MASK) == generation8;
 
-  return cnt / ClusterSize;
+    return cnt / ClusterSize;
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/tt.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,89 +19,92 @@
 #ifndef TT_H_INCLUDED
 #define TT_H_INCLUDED
 
+#include <cstddef>
+#include <cstdint>
+
 #include "misc.h"
 #include "types.h"
 
 namespace Stockfish {
 
-/// TTEntry struct is the 10 bytes transposition table entry, defined as below:
-///
-/// key        16 bit
-/// depth       8 bit
-/// generation  5 bit
-/// pv node     1 bit
-/// bound type  2 bit
-/// move       16 bit
-/// value      16 bit
-/// eval value 16 bit
-
+// TTEntry struct is the 10 bytes transposition table entry, defined as below:
+//
+// key        16 bit
+// depth       8 bit
+// generation  5 bit
+// pv node     1 bit
+// bound type  2 bit
+// move       16 bit
+// value      16 bit
+// eval value 16 bit
 struct TTEntry {
 
-  Move  move()  const { return (Move )move16; }
-  Value value() const { return (Value)value16; }
-  Value eval()  const { return (Value)eval16; }
-  Depth depth() const { return (Depth)depth8 + DEPTH_OFFSET; }
-  bool is_pv()  const { return (bool)(genBound8 & 0x4); }
-  Bound bound() const { return (Bound)(genBound8 & 0x3); }
-  void save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev);
+    Move  move() const { return Move(move16); }
+    Value value() const { return Value(value16); }
+    Value eval() const { return Value(eval16); }
+    Depth depth() const { return Depth(depth8 + DEPTH_OFFSET); }
+    bool  is_pv() const { return bool(genBound8 & 0x4); }
+    Bound bound() const { return Bound(genBound8 & 0x3); }
+    void  save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev, uint8_t generation8);
 
-private:
-  friend class TranspositionTable;
+   private:
+    friend class TranspositionTable;
 
-  uint16_t key16;
-  uint8_t  depth8;
-  uint8_t  genBound8;
-  uint16_t move16;
-  int16_t  value16;
-  int16_t  eval16;
+    uint16_t key16;
+    uint8_t  depth8;
+    uint8_t  genBound8;
+    Move     move16;
+    int16_t  value16;
+    int16_t  eval16;
 };
 
 
-/// A TranspositionTable is an array of Cluster, of size clusterCount. Each
-/// cluster consists of ClusterSize number of TTEntry. Each non-empty TTEntry
-/// contains information on exactly one position. The size of a Cluster should
-/// divide the size of a cache line for best performance, as the cacheline is
-/// prefetched when possible.
-
+// A TranspositionTable is an array of Cluster, of size clusterCount. Each
+// cluster consists of ClusterSize number of TTEntry. Each non-empty TTEntry
+// contains information on exactly one position. The size of a Cluster should
+// divide the size of a cache line for best performance, as the cacheline is
+// prefetched when possible.
 class TranspositionTable {
 
-  static constexpr int ClusterSize = 3;
+    static constexpr int ClusterSize = 3;
 
-  struct Cluster {
-    TTEntry entry[ClusterSize];
-    char padding[2]; // Pad to 32 bytes
-  };
+    struct Cluster {
+        TTEntry entry[ClusterSize];
+        char    padding[2];  // Pad to 32 bytes
+    };
 
-  static_assert(sizeof(Cluster) == 32, "Unexpected Cluster size");
+    static_assert(sizeof(Cluster) == 32, "Unexpected Cluster size");
 
-  // Constants used to refresh the hash table periodically
-  static constexpr unsigned GENERATION_BITS  = 3;                                // nb of bits reserved for other things
-  static constexpr int      GENERATION_DELTA = (1 << GENERATION_BITS);           // increment for generation field
-  static constexpr int      GENERATION_CYCLE = 255 + (1 << GENERATION_BITS);     // cycle length
-  static constexpr int      GENERATION_MASK  = (0xFF << GENERATION_BITS) & 0xFF; // mask to pull out generation number
+    // Constants used to refresh the hash table periodically
+    static constexpr unsigned GENERATION_BITS = 3;  // nb of bits reserved for other things
+    static constexpr int      GENERATION_DELTA =
+      (1 << GENERATION_BITS);  // increment for generation field
+    static constexpr int GENERATION_CYCLE = 255 + (1 << GENERATION_BITS);  // cycle length
+    static constexpr int GENERATION_MASK =
+      (0xFF << GENERATION_BITS) & 0xFF;  // mask to pull out generation number
 
-public:
- ~TranspositionTable() { aligned_large_pages_free(table); }
-  void new_search() { generation8 += GENERATION_DELTA; } // Lower bits are used for other things
-  TTEntry* probe(const Key key, bool& found) const;
-  int hashfull() const;
-  void resize(size_t mbSize);
-  void clear();
+   public:
+    ~TranspositionTable() { aligned_large_pages_free(table); }
+    void new_search() { generation8 += GENERATION_DELTA; }  // Lower bits are used for other things
+    TTEntry* probe(const Key key, bool& found) const;
+    int      hashfull() const;
+    void     resize(size_t mbSize, int threadCount);
+    void     clear(size_t threadCount);
 
-  TTEntry* first_entry(const Key key) const {
-    return &table[mul_hi64(key, clusterCount)].entry[0];
-  }
+    TTEntry* first_entry(const Key key) const {
+        return &table[mul_hi64(key, clusterCount)].entry[0];
+    }
 
-private:
-  friend struct TTEntry;
+    uint8_t generation() const { return generation8; }
 
-  size_t clusterCount;
-  Cluster* table;
-  uint8_t generation8; // Size must be not bigger than TTEntry::genBound8
+   private:
+    friend struct TTEntry;
+
+    size_t   clusterCount;
+    Cluster* table       = nullptr;
+    uint8_t  generation8 = 0;  // Size must be not bigger than TTEntry::genBound8
 };
 
-extern TranspositionTable TT;
+}  // namespace Stockfish
 
-} // namespace Stockfish
-
-#endif // #ifndef TT_H_INCLUDED
+#endif  // #ifndef TT_H_INCLUDED

src/tune.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,100 +16,88 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "tune.h"
+
 #include <algorithm>
 #include <iostream>
+#include <map>
 #include <sstream>
+#include <string>
 
-#include "types.h"
-#include "misc.h"
-#include "uci.h"
+#include "ucioption.h"
 
 using std::string;
 
 namespace Stockfish {
 
-bool Tune::update_on_last;
-const UCI::Option* LastOption = nullptr;
+bool                              Tune::update_on_last;
+const Option*                     LastOption = nullptr;
+OptionsMap*                       Tune::options;
 static std::map<std::string, int> TuneResults;
 
 string Tune::next(string& names, bool pop) {
 
-  string name;
+    string name;
 
-  do {
-      string token = names.substr(0, names.find(','));
+    do
+    {
+        string token = names.substr(0, names.find(','));
 
-      if (pop)
-          names.erase(0, token.size() + 1);
+        if (pop)
+            names.erase(0, token.size() + 1);
 
-      std::stringstream ws(token);
-      name += (ws >> token, token); // Remove trailing whitespace
+        std::stringstream ws(token);
+        name += (ws >> token, token);  // Remove trailing whitespace
 
-  } while (  std::count(name.begin(), name.end(), '(')
-           - std::count(name.begin(), name.end(), ')'));
+    } while (std::count(name.begin(), name.end(), '(') - std::count(name.begin(), name.end(), ')'));
 
-  return name;
+    return name;
 }
 
-static void on_tune(const UCI::Option& o) {
+static void on_tune(const Option& o) {
 
-  if (!Tune::update_on_last || LastOption == &o)
-      Tune::read_options();
+    if (!Tune::update_on_last || LastOption == &o)
+        Tune::read_options();
 }
 
-static void make_option(const string& n, int v, const SetRange& r) {
+static void make_option(OptionsMap* options, const string& n, int v, const SetRange& r) {
 
-  // Do not generate option when there is nothing to tune (ie. min = max)
-  if (r(v).first == r(v).second)
-      return;
+    // Do not generate option when there is nothing to tune (ie. min = max)
+    if (r(v).first == r(v).second)
+        return;
 
-  if (TuneResults.count(n))
-      v = TuneResults[n];
+    if (TuneResults.count(n))
+        v = TuneResults[n];
 
-  Options[n] << UCI::Option(v, r(v).first, r(v).second, on_tune);
-  LastOption = &Options[n];
+    (*options)[n] << Option(v, r(v).first, r(v).second, on_tune);
+    LastOption = &((*options)[n]);
 
-  // Print formatted parameters, ready to be copy-pasted in Fishtest
-  std::cout << n << ","
-            << v << ","
-            << r(v).first << "," << r(v).second << ","
-            << (r(v).second - r(v).first) / 20.0 << ","
-            << "0.0020"
-            << std::endl;
+    // Print formatted parameters, ready to be copy-pasted in Fishtest
+    std::cout << n << "," << v << "," << r(v).first << "," << r(v).second << ","
+              << (r(v).second - r(v).first) / 20.0 << ","
+              << "0.0020" << std::endl;
 }
 
-template<> void Tune::Entry<int>::init_option() { make_option(name, value, range); }
-
-template<> void Tune::Entry<int>::read_option() {
-  if (Options.count(name))
-      value = int(Options[name]);
+template<>
+void Tune::Entry<int>::init_option() {
+    make_option(options, name, value, range);
 }
 
-template<> void Tune::Entry<Value>::init_option() { make_option(name, value, range); }
-
-template<> void Tune::Entry<Value>::read_option() {
-  if (Options.count(name))
-      value = Value(int(Options[name]));
-}
-
-template<> void Tune::Entry<Score>::init_option() {
-  make_option("m" + name, mg_value(value), range);
-  make_option("e" + name, eg_value(value), range);
-}
-
-template<> void Tune::Entry<Score>::read_option() {
-  if (Options.count("m" + name))
-      value = make_score(int(Options["m" + name]), eg_value(value));
-
-  if (Options.count("e" + name))
-      value = make_score(mg_value(value), int(Options["e" + name]));
+template<>
+void Tune::Entry<int>::read_option() {
+    if (options->count(name))
+        value = int((*options)[name]);
 }
 
 // Instead of a variable here we have a PostUpdate function: just call it
-template<> void Tune::Entry<Tune::PostUpdate>::init_option() {}
-template<> void Tune::Entry<Tune::PostUpdate>::read_option() { value(); }
+template<>
+void Tune::Entry<Tune::PostUpdate>::init_option() {}
+template<>
+void Tune::Entry<Tune::PostUpdate>::read_option() {
+    value();
+}
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
 
 // Init options with tuning session results instead of default values. Useful to
@@ -121,13 +109,10 @@ template<> void Tune::Entry<Tune::PostUpdate>::read_option() { value(); }
 //
 // Then paste the output below, as the function body
 
-#include <cmath>
 
 namespace Stockfish {
 
-void Tune::read_results() {
-
-  /* ...insert your values here... */
+void Tune::read_results() { /* ...insert your values here... */
 }
 
-} // namespace Stockfish
+}  // namespace Stockfish

src/tune.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,145 +19,163 @@
 #ifndef TUNE_H_INCLUDED
 #define TUNE_H_INCLUDED
 
+#include <cstddef>
 #include <memory>
 #include <string>
-#include <type_traits>
+#include <type_traits>  // IWYU pragma: keep
+#include <utility>
 #include <vector>
 
 namespace Stockfish {
 
-using Range = std::pair<int, int>; // Option's min-max values
-using RangeFun = Range (int);
+class OptionsMap;
+
+using Range    = std::pair<int, int>;  // Option's min-max values
+using RangeFun = Range(int);
 
 // Default Range function, to calculate Option's min-max values
-inline Range default_range(int v) {
-  return v > 0 ? Range(0, 2 * v) : Range(2 * v, 0);
-}
+inline Range default_range(int v) { return v > 0 ? Range(0, 2 * v) : Range(2 * v, 0); }
 
 struct SetRange {
-  explicit SetRange(RangeFun f) : fun(f) {}
-  SetRange(int min, int max) : fun(nullptr), range(min, max) {}
-  Range operator()(int v) const { return fun ? fun(v) : range; }
+    explicit SetRange(RangeFun f) :
+        fun(f) {}
+    SetRange(int min, int max) :
+        fun(nullptr),
+        range(min, max) {}
+    Range operator()(int v) const { return fun ? fun(v) : range; }
 
-  RangeFun* fun;
-  Range range;
+    RangeFun* fun;
+    Range     range;
 };
 
 #define SetDefaultRange SetRange(default_range)
 
 
-/// Tune class implements the 'magic' code that makes the setup of a fishtest
-/// tuning session as easy as it can be. Mainly you have just to remove const
-/// qualifiers from the variables you want to tune and flag them for tuning, so
-/// if you have:
-///
-///   const Score myScore = S(10, 15);
-///   const Value myValue[][2] = { { V(100), V(20) }, { V(7), V(78) } };
-///
-/// If you have a my_post_update() function to run after values have been updated,
-/// and a my_range() function to set custom Option's min-max values, then you just
-/// remove the 'const' qualifiers and write somewhere below in the file:
-///
-///   TUNE(SetRange(my_range), myScore, myValue, my_post_update);
-///
-/// You can also set the range directly, and restore the default at the end
-///
-///   TUNE(SetRange(-100, 100), myScore, SetDefaultRange);
-///
-/// In case update function is slow and you have many parameters, you can add:
-///
-///   UPDATE_ON_LAST();
-///
-/// And the values update, including post update function call, will be done only
-/// once, after the engine receives the last UCI option, that is the one defined
-/// and created as the last one, so the GUI should send the options in the same
-/// order in which have been defined.
+// Tune class implements the 'magic' code that makes the setup of a fishtest tuning
+// session as easy as it can be. Mainly you have just to remove const qualifiers
+// from the variables you want to tune and flag them for tuning, so if you have:
+//
+//   const Value myValue[][2] = { { V(100), V(20) }, { V(7), V(78) } };
+//
+// If you have a my_post_update() function to run after values have been updated,
+// and a my_range() function to set custom Option's min-max values, then you just
+// remove the 'const' qualifiers and write somewhere below in the file:
+//
+//   TUNE(SetRange(my_range), myValue, my_post_update);
+//
+// You can also set the range directly, and restore the default at the end
+//
+//   TUNE(SetRange(-100, 100), myValue, SetDefaultRange);
+//
+// In case update function is slow and you have many parameters, you can add:
+//
+//   UPDATE_ON_LAST();
+//
+// And the values update, including post update function call, will be done only
+// once, after the engine receives the last UCI option, that is the one defined
+// and created as the last one, so the GUI should send the options in the same
+// order in which have been defined.
 
 class Tune {
 
-  using PostUpdate = void (); // Post-update function
+    using PostUpdate = void();  // Post-update function
 
-  Tune() { read_results(); }
-  Tune(const Tune&) = delete;
-  void operator=(const Tune&) = delete;
-  void read_results();
+    Tune() { read_results(); }
+    Tune(const Tune&)           = delete;
+    void operator=(const Tune&) = delete;
+    void read_results();
 
-  static Tune& instance() { static Tune t; return t; } // Singleton
+    static Tune& instance() {
+        static Tune t;
+        return t;
+    }  // Singleton
 
-  // Use polymorphism to accommodate Entry of different types in the same vector
-  struct EntryBase {
-    virtual ~EntryBase() = default;
-    virtual void init_option() = 0;
-    virtual void read_option() = 0;
-  };
+    // Use polymorphism to accommodate Entry of different types in the same vector
+    struct EntryBase {
+        virtual ~EntryBase()       = default;
+        virtual void init_option() = 0;
+        virtual void read_option() = 0;
+    };
 
-  template<typename T>
-  struct Entry : public EntryBase {
+    template<typename T>
+    struct Entry: public EntryBase {
 
-    static_assert(!std::is_const<T>::value, "Parameter cannot be const!");
+        static_assert(!std::is_const_v<T>, "Parameter cannot be const!");
 
-    static_assert(   std::is_same<T,   int>::value
-                  || std::is_same<T, Value>::value
-                  || std::is_same<T, Score>::value
-                  || std::is_same<T, PostUpdate>::value, "Parameter type not supported!");
+        static_assert(std::is_same_v<T, int> || std::is_same_v<T, PostUpdate>,
+                      "Parameter type not supported!");
 
-    Entry(const std::string& n, T& v, const SetRange& r) : name(n), value(v), range(r) {}
-    void operator=(const Entry&) = delete; // Because 'value' is a reference
-    void init_option() override;
-    void read_option() override;
+        Entry(const std::string& n, T& v, const SetRange& r) :
+            name(n),
+            value(v),
+            range(r) {}
+        void operator=(const Entry&) = delete;  // Because 'value' is a reference
+        void init_option() override;
+        void read_option() override;
 
-    std::string name;
-    T& value;
-    SetRange range;
-  };
+        std::string name;
+        T&          value;
+        SetRange    range;
+    };
 
-  // Our facility to fill the container, each Entry corresponds to a parameter
-  // to tune. We use variadic templates to deal with an unspecified number of
-  // entries, each one of a possible different type.
-  static std::string next(std::string& names, bool pop = true);
+    // Our facility to fill the container, each Entry corresponds to a parameter
+    // to tune. We use variadic templates to deal with an unspecified number of
+    // entries, each one of a possible different type.
+    static std::string next(std::string& names, bool pop = true);
 
-  int add(const SetRange&, std::string&&) { return 0; }
+    int add(const SetRange&, std::string&&) { return 0; }
 
-  template<typename T, typename... Args>
-  int add(const SetRange& range, std::string&& names, T& value, Args&&... args) {
-    list.push_back(std::unique_ptr<EntryBase>(new Entry<T>(next(names), value, range)));
-    return add(range, std::move(names), args...);
-  }
+    template<typename T, typename... Args>
+    int add(const SetRange& range, std::string&& names, T& value, Args&&... args) {
+        list.push_back(std::unique_ptr<EntryBase>(new Entry<T>(next(names), value, range)));
+        return add(range, std::move(names), args...);
+    }
 
-  // Template specialization for arrays: recursively handle multi-dimensional arrays
-  template<typename T, size_t N, typename... Args>
-  int add(const SetRange& range, std::string&& names, T (&value)[N], Args&&... args) {
-    for (size_t i = 0; i < N; i++)
-        add(range, next(names, i == N - 1) + "[" + std::to_string(i) + "]", value[i]);
-    return add(range, std::move(names), args...);
-  }
+    // Template specialization for arrays: recursively handle multi-dimensional arrays
+    template<typename T, size_t N, typename... Args>
+    int add(const SetRange& range, std::string&& names, T (&value)[N], Args&&... args) {
+        for (size_t i = 0; i < N; i++)
+            add(range, next(names, i == N - 1) + "[" + std::to_string(i) + "]", value[i]);
+        return add(range, std::move(names), args...);
+    }
 
-  // Template specialization for SetRange
-  template<typename... Args>
-  int add(const SetRange&, std::string&& names, SetRange& value, Args&&... args) {
-    return add(value, (next(names), std::move(names)), args...);
-  }
+    // Template specialization for SetRange
+    template<typename... Args>
+    int add(const SetRange&, std::string&& names, SetRange& value, Args&&... args) {
+        return add(value, (next(names), std::move(names)), args...);
+    }
 
-  std::vector<std::unique_ptr<EntryBase>> list;
+    std::vector<std::unique_ptr<EntryBase>> list;
 
-public:
-  template<typename... Args>
-  static int add(const std::string& names, Args&&... args) {
-    return instance().add(SetDefaultRange, names.substr(1, names.size() - 2), args...); // Remove trailing parenthesis
-  }
-  static void init() { for (auto& e : instance().list) e->init_option(); read_options(); } // Deferred, due to UCI::Options access
-  static void read_options() { for (auto& e : instance().list) e->read_option(); }
-  static bool update_on_last;
+   public:
+    template<typename... Args>
+    static int add(const std::string& names, Args&&... args) {
+        return instance().add(SetDefaultRange, names.substr(1, names.size() - 2),
+                              args...);  // Remove trailing parenthesis
+    }
+    static void init(OptionsMap& o) {
+        options = &o;
+        for (auto& e : instance().list)
+            e->init_option();
+        read_options();
+    }  // Deferred, due to UCI::Options access
+    static void read_options() {
+        for (auto& e : instance().list)
+            e->read_option();
+    }
+
+    static bool        update_on_last;
+    static OptionsMap* options;
 };
 
-// Some macro magic :-) we define a dummy int variable that compiler initializes calling Tune::add()
+// Some macro magic :-) we define a dummy int variable that the compiler initializes calling Tune::add()
 #define STRINGIFY(x) #x
-#define UNIQUE2(x, y) x ## y
-#define UNIQUE(x, y) UNIQUE2(x, y) // Two indirection levels to expand __LINE__
+#define UNIQUE2(x, y) x##y
+#define UNIQUE(x, y) UNIQUE2(x, y)  // Two indirection levels to expand __LINE__
 #define TUNE(...) int UNIQUE(p, __LINE__) = Tune::add(STRINGIFY((__VA_ARGS__)), __VA_ARGS__)
 
 #define UPDATE_ON_LAST() bool UNIQUE(p, __LINE__) = Tune::update_on_last = true
 
-} // namespace Stockfish
+}  // namespace Stockfish
 
-#endif // #ifndef TUNE_H_INCLUDED
+#endif  // #ifndef TUNE_H_INCLUDED

src/types.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,475 +17,395 @@
 */
 
 #ifndef TYPES_H_INCLUDED
-#define TYPES_H_INCLUDED
+    #define TYPES_H_INCLUDED
 
-/// When compiling with provided Makefile (e.g. for Linux and OSX), configuration
-/// is done automatically. To get started type 'make help'.
-///
-/// When Makefile is not used (e.g. with Microsoft Visual Studio) some switches
-/// need to be set manually:
-///
-/// -DNDEBUG      | Disable debugging mode. Always use this for release.
-///
-/// -DNO_PREFETCH | Disable use of prefetch asm-instruction. You may need this to
-///               | run on some very old machines.
-///
-/// -DUSE_POPCNT  | Add runtime support for use of popcnt asm-instruction. Works
-///               | only in 64-bit mode and requires hardware with popcnt support.
-///
-/// -DUSE_PEXT    | Add runtime support for use of pext asm-instruction. Works
-///               | only in 64-bit mode and requires hardware with pext support.
+// When compiling with provided Makefile (e.g. for Linux and OSX), configuration
+// is done automatically. To get started type 'make help'.
+//
+// When Makefile is not used (e.g. with Microsoft Visual Studio) some switches
+// need to be set manually:
+//
+// -DNDEBUG      | Disable debugging mode. Always use this for release.
+//
+// -DNO_PREFETCH | Disable use of prefetch asm-instruction. You may need this to
+//               | run on some very old machines.
+//
+// -DUSE_POPCNT  | Add runtime support for use of popcnt asm-instruction. Works
+//               | only in 64-bit mode and requires hardware with popcnt support.
+//
+// -DUSE_PEXT    | Add runtime support for use of pext asm-instruction. Works
+//               | only in 64-bit mode and requires hardware with pext support.
 
-#include <cassert>
-#include <cctype>
-#include <cstdint>
-#include <cstdlib>
-#include <algorithm>
+    #include <cassert>
+    #include <cstdint>
 
-#if defined(_MSC_VER)
-// Disable some silly and noisy warning from MSVC compiler
-#pragma warning(disable: 4127) // Conditional expression is constant
-#pragma warning(disable: 4146) // Unary minus operator applied to unsigned type
-#pragma warning(disable: 4800) // Forcing value to bool 'true' or 'false'
-#endif
+    #if defined(_MSC_VER)
+        // Disable some silly and noisy warnings from MSVC compiler
+        #pragma warning(disable: 4127)  // Conditional expression is constant
+        #pragma warning(disable: 4146)  // Unary minus operator applied to unsigned type
+        #pragma warning(disable: 4800)  // Forcing value to bool 'true' or 'false'
+    #endif
 
-/// Predefined macros hell:
-///
-/// __GNUC__           Compiler is gcc, Clang or Intel on Linux
-/// __INTEL_COMPILER   Compiler is Intel
-/// _MSC_VER           Compiler is MSVC or Intel on Windows
-/// _WIN32             Building on Windows (any)
-/// _WIN64             Building on Windows 64 bit
+// Predefined macros hell:
+//
+// __GNUC__                Compiler is GCC, Clang or ICX
+// __clang__               Compiler is Clang or ICX
+// __INTEL_LLVM_COMPILER   Compiler is ICX
+// _MSC_VER                Compiler is MSVC
+// _WIN32                  Building on Windows (any)
+// _WIN64                  Building on Windows 64 bit
 
-#if defined(__GNUC__ ) && (__GNUC__ < 9 || (__GNUC__ == 9 && __GNUC_MINOR__ <= 2)) && defined(_WIN32) && !defined(__clang__)
-#define ALIGNAS_ON_STACK_VARIABLES_BROKEN
-#endif
+    #if defined(__GNUC__) && (__GNUC__ < 9 || (__GNUC__ == 9 && __GNUC_MINOR__ <= 2)) \
+      && defined(_WIN32) && !defined(__clang__)
+        #define ALIGNAS_ON_STACK_VARIABLES_BROKEN
+    #endif
 
-#define ASSERT_ALIGNED(ptr, alignment) assert(reinterpret_cast<uintptr_t>(ptr) % alignment == 0)
+    #define ASSERT_ALIGNED(ptr, alignment) assert(reinterpret_cast<uintptr_t>(ptr) % alignment == 0)
 
-#if defined(_WIN64) && defined(_MSC_VER) // No Makefile used
-#  include <intrin.h> // Microsoft header for _BitScanForward64()
-#  define IS_64BIT
-#endif
+    #if defined(_WIN64) && defined(_MSC_VER)  // No Makefile used
+        #include <intrin.h>                   // Microsoft header for _BitScanForward64()
+        #define IS_64BIT
+    #endif
 
-#if defined(USE_POPCNT) && (defined(__INTEL_COMPILER) || defined(_MSC_VER))
-#  include <nmmintrin.h> // Intel and Microsoft header for _mm_popcnt_u64()
-#endif
+    #if defined(USE_POPCNT) && defined(_MSC_VER)
+        #include <nmmintrin.h>  // Microsoft header for _mm_popcnt_u64()
+    #endif
 
-#if !defined(NO_PREFETCH) && (defined(__INTEL_COMPILER) || defined(_MSC_VER))
-#  include <xmmintrin.h> // Intel and Microsoft header for _mm_prefetch()
-#endif
+    #if !defined(NO_PREFETCH) && defined(_MSC_VER)
+        #include <xmmintrin.h>  // Microsoft header for _mm_prefetch()
+    #endif
 
-#if defined(USE_PEXT)
-#  include <immintrin.h> // Header for _pext_u64() intrinsic
-#  define pext(b, m) _pext_u64(b, m)
-#else
-#  define pext(b, m) 0
-#endif
+    #if defined(USE_PEXT)
+        #include <immintrin.h>  // Header for _pext_u64() intrinsic
+        #define pext(b, m) _pext_u64(b, m)
+    #else
+        #define pext(b, m) 0
+    #endif
 
 namespace Stockfish {
 
-#ifdef USE_POPCNT
+    #ifdef USE_POPCNT
 constexpr bool HasPopCnt = true;
-#else
+    #else
 constexpr bool HasPopCnt = false;
-#endif
+    #endif
 
-#ifdef USE_PEXT
+    #ifdef USE_PEXT
 constexpr bool HasPext = true;
-#else
+    #else
 constexpr bool HasPext = false;
-#endif
+    #endif
 
-#ifdef IS_64BIT
+    #ifdef IS_64BIT
 constexpr bool Is64Bit = true;
-#else
+    #else
 constexpr bool Is64Bit = false;
-#endif
+    #endif
 
-using Key = uint64_t;
+using Key      = uint64_t;
 using Bitboard = uint64_t;
 
 constexpr int MAX_MOVES = 256;
 constexpr int MAX_PLY   = 246;
 
-/// A move needs 16 bits to be stored
-///
-/// bit  0- 5: destination square (from 0 to 63)
-/// bit  6-11: origin square (from 0 to 63)
-/// bit 12-13: promotion piece type - 2 (from KNIGHT-2 to QUEEN-2)
-/// bit 14-15: special move flag: promotion (1), en passant (2), castling (3)
-/// NOTE: en passant bit is set only when a pawn can be captured
-///
-/// Special cases are MOVE_NONE and MOVE_NULL. We can sneak these in because in
-/// any normal move destination square is always different from origin square
-/// while MOVE_NONE and MOVE_NULL have the same origin and destination square.
-
-enum Move : int {
-  MOVE_NONE,
-  MOVE_NULL = 65
-};
-
-enum MoveType {
-  NORMAL,
-  PROMOTION = 1 << 14,
-  EN_PASSANT = 2 << 14,
-  CASTLING  = 3 << 14
-};
-
 enum Color {
-  WHITE, BLACK, COLOR_NB = 2
+    WHITE,
+    BLACK,
+    COLOR_NB = 2
 };
 
 enum CastlingRights {
-  NO_CASTLING,
-  WHITE_OO,
-  WHITE_OOO = WHITE_OO << 1,
-  BLACK_OO  = WHITE_OO << 2,
-  BLACK_OOO = WHITE_OO << 3,
+    NO_CASTLING,
+    WHITE_OO,
+    WHITE_OOO = WHITE_OO << 1,
+    BLACK_OO  = WHITE_OO << 2,
+    BLACK_OOO = WHITE_OO << 3,
 
-  KING_SIDE      = WHITE_OO  | BLACK_OO,
-  QUEEN_SIDE     = WHITE_OOO | BLACK_OOO,
-  WHITE_CASTLING = WHITE_OO  | WHITE_OOO,
-  BLACK_CASTLING = BLACK_OO  | BLACK_OOO,
-  ANY_CASTLING   = WHITE_CASTLING | BLACK_CASTLING,
+    KING_SIDE      = WHITE_OO | BLACK_OO,
+    QUEEN_SIDE     = WHITE_OOO | BLACK_OOO,
+    WHITE_CASTLING = WHITE_OO | WHITE_OOO,
+    BLACK_CASTLING = BLACK_OO | BLACK_OOO,
+    ANY_CASTLING   = WHITE_CASTLING | BLACK_CASTLING,
 
-  CASTLING_RIGHT_NB = 16
-};
-
-enum Phase {
-  PHASE_ENDGAME,
-  PHASE_MIDGAME = 128,
-  MG = 0, EG = 1, PHASE_NB = 2
-};
-
-enum ScaleFactor {
-  SCALE_FACTOR_DRAW    = 0,
-  SCALE_FACTOR_NORMAL  = 64,
-  SCALE_FACTOR_MAX     = 128,
-  SCALE_FACTOR_NONE    = 255
+    CASTLING_RIGHT_NB = 16
 };
 
 enum Bound {
-  BOUND_NONE,
-  BOUND_UPPER,
-  BOUND_LOWER,
-  BOUND_EXACT = BOUND_UPPER | BOUND_LOWER
+    BOUND_NONE,
+    BOUND_UPPER,
+    BOUND_LOWER,
+    BOUND_EXACT = BOUND_UPPER | BOUND_LOWER
 };
 
-enum Value : int {
-  VALUE_ZERO      = 0,
-  VALUE_DRAW      = 0,
-  VALUE_KNOWN_WIN = 10000,
-  VALUE_MATE      = 32000,
-  VALUE_INFINITE  = 32001,
-  VALUE_NONE      = 32002,
+// Value is used as an alias for int16_t, this is done to differentiate between
+// a search value and any other integer value. The values used in search are always
+// supposed to be in the range (-VALUE_NONE, VALUE_NONE] and should not exceed this range.
+using Value = int;
 
-  VALUE_TB_WIN_IN_MAX_PLY  =  VALUE_MATE - 2 * MAX_PLY,
-  VALUE_TB_LOSS_IN_MAX_PLY = -VALUE_TB_WIN_IN_MAX_PLY,
-  VALUE_MATE_IN_MAX_PLY  =  VALUE_MATE - MAX_PLY,
-  VALUE_MATED_IN_MAX_PLY = -VALUE_MATE_IN_MAX_PLY,
+constexpr Value VALUE_ZERO     = 0;
+constexpr Value VALUE_DRAW     = 0;
+constexpr Value VALUE_NONE     = 32002;
+constexpr Value VALUE_INFINITE = 32001;
 
-  // In the code, we make the assumption that these values
-  // are such that non_pawn_material() can be used to uniquely
-  // identify the material on the board.
-  PawnValueMg   = 126,   PawnValueEg   = 208,
-  KnightValueMg = 781,   KnightValueEg = 854,
-  BishopValueMg = 825,   BishopValueEg = 915,
-  RookValueMg   = 1276,  RookValueEg   = 1380,
-  QueenValueMg  = 2538,  QueenValueEg  = 2682,
+constexpr Value VALUE_MATE             = 32000;
+constexpr Value VALUE_MATE_IN_MAX_PLY  = VALUE_MATE - MAX_PLY;
+constexpr Value VALUE_MATED_IN_MAX_PLY = -VALUE_MATE_IN_MAX_PLY;
 
-  MidgameLimit  = 15258, EndgameLimit  = 3915
-};
+constexpr Value VALUE_TB                 = VALUE_MATE_IN_MAX_PLY - 1;
+constexpr Value VALUE_TB_WIN_IN_MAX_PLY  = VALUE_TB - MAX_PLY;
+constexpr Value VALUE_TB_LOSS_IN_MAX_PLY = -VALUE_TB_WIN_IN_MAX_PLY;
 
+// In the code, we make the assumption that these values
+// are such that non_pawn_material() can be used to uniquely
+// identify the material on the board.
+constexpr Value PawnValue   = 208;
+constexpr Value KnightValue = 781;
+constexpr Value BishopValue = 825;
+constexpr Value RookValue   = 1276;
+constexpr Value QueenValue  = 2538;
+
+
+// clang-format off
 enum PieceType {
-  NO_PIECE_TYPE, PAWN, KNIGHT, BISHOP, ROOK, QUEEN, KING,
-  ALL_PIECES = 0,
-  PIECE_TYPE_NB = 8
+    NO_PIECE_TYPE, PAWN, KNIGHT, BISHOP, ROOK, QUEEN, KING,
+    ALL_PIECES = 0,
+    PIECE_TYPE_NB = 8
 };
 
 enum Piece {
-  NO_PIECE,
-  W_PAWN = PAWN,     W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING,
-  B_PAWN = PAWN + 8, B_KNIGHT, B_BISHOP, B_ROOK, B_QUEEN, B_KING,
-  PIECE_NB = 16
+    NO_PIECE,
+    W_PAWN = PAWN,     W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING,
+    B_PAWN = PAWN + 8, B_KNIGHT, B_BISHOP, B_ROOK, B_QUEEN, B_KING,
+    PIECE_NB = 16
 };
+// clang-format on
 
-constexpr Value PieceValue[PHASE_NB][PIECE_NB] = {
-  { VALUE_ZERO, PawnValueMg, KnightValueMg, BishopValueMg, RookValueMg, QueenValueMg, VALUE_ZERO, VALUE_ZERO,
-    VALUE_ZERO, PawnValueMg, KnightValueMg, BishopValueMg, RookValueMg, QueenValueMg, VALUE_ZERO, VALUE_ZERO },
-  { VALUE_ZERO, PawnValueEg, KnightValueEg, BishopValueEg, RookValueEg, QueenValueEg, VALUE_ZERO, VALUE_ZERO,
-    VALUE_ZERO, PawnValueEg, KnightValueEg, BishopValueEg, RookValueEg, QueenValueEg, VALUE_ZERO, VALUE_ZERO }
-};
+constexpr Value PieceValue[PIECE_NB] = {
+  VALUE_ZERO, PawnValue, KnightValue, BishopValue, RookValue, QueenValue, VALUE_ZERO, VALUE_ZERO,
+  VALUE_ZERO, PawnValue, KnightValue, BishopValue, RookValue, QueenValue, VALUE_ZERO, VALUE_ZERO};
 
 using Depth = int;
 
 enum : int {
-  DEPTH_QS_CHECKS     =  0,
-  DEPTH_QS_NO_CHECKS  = -1,
-  DEPTH_QS_RECAPTURES = -5,
+    DEPTH_QS_CHECKS    = 0,
+    DEPTH_QS_NO_CHECKS = -1,
 
-  DEPTH_NONE   = -6,
+    DEPTH_NONE = -6,
 
-  DEPTH_OFFSET = -7 // value used only for TT entry occupancy check
+    DEPTH_OFFSET = -7  // value used only for TT entry occupancy check
 };
 
+// clang-format off
 enum Square : int {
-  SQ_A1, SQ_B1, SQ_C1, SQ_D1, SQ_E1, SQ_F1, SQ_G1, SQ_H1,
-  SQ_A2, SQ_B2, SQ_C2, SQ_D2, SQ_E2, SQ_F2, SQ_G2, SQ_H2,
-  SQ_A3, SQ_B3, SQ_C3, SQ_D3, SQ_E3, SQ_F3, SQ_G3, SQ_H3,
-  SQ_A4, SQ_B4, SQ_C4, SQ_D4, SQ_E4, SQ_F4, SQ_G4, SQ_H4,
-  SQ_A5, SQ_B5, SQ_C5, SQ_D5, SQ_E5, SQ_F5, SQ_G5, SQ_H5,
-  SQ_A6, SQ_B6, SQ_C6, SQ_D6, SQ_E6, SQ_F6, SQ_G6, SQ_H6,
-  SQ_A7, SQ_B7, SQ_C7, SQ_D7, SQ_E7, SQ_F7, SQ_G7, SQ_H7,
-  SQ_A8, SQ_B8, SQ_C8, SQ_D8, SQ_E8, SQ_F8, SQ_G8, SQ_H8,
-  SQ_NONE,
+    SQ_A1, SQ_B1, SQ_C1, SQ_D1, SQ_E1, SQ_F1, SQ_G1, SQ_H1,
+    SQ_A2, SQ_B2, SQ_C2, SQ_D2, SQ_E2, SQ_F2, SQ_G2, SQ_H2,
+    SQ_A3, SQ_B3, SQ_C3, SQ_D3, SQ_E3, SQ_F3, SQ_G3, SQ_H3,
+    SQ_A4, SQ_B4, SQ_C4, SQ_D4, SQ_E4, SQ_F4, SQ_G4, SQ_H4,
+    SQ_A5, SQ_B5, SQ_C5, SQ_D5, SQ_E5, SQ_F5, SQ_G5, SQ_H5,
+    SQ_A6, SQ_B6, SQ_C6, SQ_D6, SQ_E6, SQ_F6, SQ_G6, SQ_H6,
+    SQ_A7, SQ_B7, SQ_C7, SQ_D7, SQ_E7, SQ_F7, SQ_G7, SQ_H7,
+    SQ_A8, SQ_B8, SQ_C8, SQ_D8, SQ_E8, SQ_F8, SQ_G8, SQ_H8,
+    SQ_NONE,
 
-  SQUARE_ZERO = 0,
-  SQUARE_NB   = 64
+    SQUARE_ZERO = 0,
+    SQUARE_NB   = 64
 };
+// clang-format on
 
 enum Direction : int {
-  NORTH =  8,
-  EAST  =  1,
-  SOUTH = -NORTH,
-  WEST  = -EAST,
+    NORTH = 8,
+    EAST  = 1,
+    SOUTH = -NORTH,
+    WEST  = -EAST,
 
-  NORTH_EAST = NORTH + EAST,
-  SOUTH_EAST = SOUTH + EAST,
-  SOUTH_WEST = SOUTH + WEST,
-  NORTH_WEST = NORTH + WEST
+    NORTH_EAST = NORTH + EAST,
+    SOUTH_EAST = SOUTH + EAST,
+    SOUTH_WEST = SOUTH + WEST,
+    NORTH_WEST = NORTH + WEST
 };
 
 enum File : int {
-  FILE_A, FILE_B, FILE_C, FILE_D, FILE_E, FILE_F, FILE_G, FILE_H, FILE_NB
+    FILE_A,
+    FILE_B,
+    FILE_C,
+    FILE_D,
+    FILE_E,
+    FILE_F,
+    FILE_G,
+    FILE_H,
+    FILE_NB
 };
 
 enum Rank : int {
-  RANK_1, RANK_2, RANK_3, RANK_4, RANK_5, RANK_6, RANK_7, RANK_8, RANK_NB
+    RANK_1,
+    RANK_2,
+    RANK_3,
+    RANK_4,
+    RANK_5,
+    RANK_6,
+    RANK_7,
+    RANK_8,
+    RANK_NB
 };
 
 // Keep track of what a move changes on the board (used by NNUE)
 struct DirtyPiece {
 
-  // Number of changed pieces
-  int dirty_num;
+    // Number of changed pieces
+    int dirty_num;
 
-  // Max 3 pieces can change in one move. A promotion with capture moves
-  // both the pawn and the captured piece to SQ_NONE and the piece promoted
-  // to from SQ_NONE to the capture square.
-  Piece piece[3];
+    // Max 3 pieces can change in one move. A promotion with capture moves
+    // both the pawn and the captured piece to SQ_NONE and the piece promoted
+    // to from SQ_NONE to the capture square.
+    Piece piece[3];
 
-  // From and to squares, which may be SQ_NONE
-  Square from[3];
-  Square to[3];
+    // From and to squares, which may be SQ_NONE
+    Square from[3];
+    Square to[3];
 };
 
-/// Score enum stores a middlegame and an endgame value in a single integer (enum).
-/// The least significant 16 bits are used to store the middlegame value and the
-/// upper 16 bits are used to store the endgame value. We have to take care to
-/// avoid left-shifting a signed int to avoid undefined behavior.
-enum Score : int { SCORE_ZERO };
+    #define ENABLE_INCR_OPERATORS_ON(T) \
+        inline T& operator++(T& d) { return d = T(int(d) + 1); } \
+        inline T& operator--(T& d) { return d = T(int(d) - 1); }
 
-constexpr Score make_score(int mg, int eg) {
-  return Score((int)((unsigned int)eg << 16) + mg);
-}
-
-/// Extracting the signed lower and upper 16 bits is not so trivial because
-/// according to the standard a simple cast to short is implementation defined
-/// and so is a right shift of a signed integer.
-inline Value eg_value(Score s) {
-  union { uint16_t u; int16_t s; } eg = { uint16_t(unsigned(s + 0x8000) >> 16) };
-  return Value(eg.s);
-}
-
-inline Value mg_value(Score s) {
-  union { uint16_t u; int16_t s; } mg = { uint16_t(unsigned(s)) };
-  return Value(mg.s);
-}
-
-#define ENABLE_BASE_OPERATORS_ON(T)                                \
-constexpr T operator+(T d1, int d2) { return T(int(d1) + d2); }    \
-constexpr T operator-(T d1, int d2) { return T(int(d1) - d2); }    \
-constexpr T operator-(T d) { return T(-int(d)); }                  \
-inline T& operator+=(T& d1, int d2) { return d1 = d1 + d2; }       \
-inline T& operator-=(T& d1, int d2) { return d1 = d1 - d2; }
-
-#define ENABLE_INCR_OPERATORS_ON(T)                                \
-inline T& operator++(T& d) { return d = T(int(d) + 1); }           \
-inline T& operator--(T& d) { return d = T(int(d) - 1); }
-
-#define ENABLE_FULL_OPERATORS_ON(T)                                \
-ENABLE_BASE_OPERATORS_ON(T)                                        \
-constexpr T operator*(int i, T d) { return T(i * int(d)); }        \
-constexpr T operator*(T d, int i) { return T(int(d) * i); }        \
-constexpr T operator/(T d, int i) { return T(int(d) / i); }        \
-constexpr int operator/(T d1, T d2) { return int(d1) / int(d2); }  \
-inline T& operator*=(T& d, int i) { return d = T(int(d) * i); }    \
-inline T& operator/=(T& d, int i) { return d = T(int(d) / i); }
-
-ENABLE_FULL_OPERATORS_ON(Value)
-ENABLE_FULL_OPERATORS_ON(Direction)
-
-ENABLE_INCR_OPERATORS_ON(Piece)
 ENABLE_INCR_OPERATORS_ON(PieceType)
 ENABLE_INCR_OPERATORS_ON(Square)
 ENABLE_INCR_OPERATORS_ON(File)
 ENABLE_INCR_OPERATORS_ON(Rank)
 
-ENABLE_BASE_OPERATORS_ON(Score)
+    #undef ENABLE_INCR_OPERATORS_ON
 
-#undef ENABLE_FULL_OPERATORS_ON
-#undef ENABLE_INCR_OPERATORS_ON
-#undef ENABLE_BASE_OPERATORS_ON
+constexpr Direction operator+(Direction d1, Direction d2) { return Direction(int(d1) + int(d2)); }
+constexpr Direction operator*(int i, Direction d) { return Direction(i * int(d)); }
 
-/// Additional operators to add a Direction to a Square
+// Additional operators to add a Direction to a Square
 constexpr Square operator+(Square s, Direction d) { return Square(int(s) + int(d)); }
 constexpr Square operator-(Square s, Direction d) { return Square(int(s) - int(d)); }
-inline Square& operator+=(Square& s, Direction d) { return s = s + d; }
-inline Square& operator-=(Square& s, Direction d) { return s = s - d; }
+inline Square&   operator+=(Square& s, Direction d) { return s = s + d; }
+inline Square&   operator-=(Square& s, Direction d) { return s = s - d; }
 
-/// Only declared but not defined. We don't want to multiply two scores due to
-/// a very high risk of overflow. So user should explicitly convert to integer.
-Score operator*(Score, Score) = delete;
+// Toggle color
+constexpr Color operator~(Color c) { return Color(c ^ BLACK); }
 
-/// Division of a Score must be handled separately for each term
-inline Score operator/(Score s, int i) {
-  return make_score(mg_value(s) / i, eg_value(s) / i);
-}
+// Swap A1 <-> A8
+constexpr Square flip_rank(Square s) { return Square(s ^ SQ_A8); }
 
-/// Multiplication of a Score by an integer. We check for overflow in debug mode.
-inline Score operator*(Score s, int i) {
+// Swap A1 <-> H1
+constexpr Square flip_file(Square s) { return Square(s ^ SQ_H1); }
 
-  Score result = Score(int(s) * i);
-
-  assert(eg_value(result) == (i * eg_value(s)));
-  assert(mg_value(result) == (i * mg_value(s)));
-  assert((i == 0) || (result / i) == s);
-
-  return result;
-}
-
-/// Multiplication of a Score by a boolean
-inline Score operator*(Score s, bool b) {
-  return b ? s : SCORE_ZERO;
-}
-
-constexpr Color operator~(Color c) {
-  return Color(c ^ BLACK); // Toggle color
-}
-
-constexpr Square flip_rank(Square s) { // Swap A1 <-> A8
-  return Square(s ^ SQ_A8);
-}
-
-constexpr Square flip_file(Square s) { // Swap A1 <-> H1
-  return Square(s ^ SQ_H1);
-}
-
-constexpr Piece operator~(Piece pc) {
-  return Piece(pc ^ 8); // Swap color of piece B_KNIGHT <-> W_KNIGHT
-}
+// Swap color of piece B_KNIGHT <-> W_KNIGHT
+constexpr Piece operator~(Piece pc) { return Piece(pc ^ 8); }
 
 constexpr CastlingRights operator&(Color c, CastlingRights cr) {
-  return CastlingRights((c == WHITE ? WHITE_CASTLING : BLACK_CASTLING) & cr);
+    return CastlingRights((c == WHITE ? WHITE_CASTLING : BLACK_CASTLING) & cr);
 }
 
-constexpr Value mate_in(int ply) {
-  return VALUE_MATE - ply;
-}
+constexpr Value mate_in(int ply) { return VALUE_MATE - ply; }
 
-constexpr Value mated_in(int ply) {
-  return -VALUE_MATE + ply;
-}
+constexpr Value mated_in(int ply) { return -VALUE_MATE + ply; }
 
-constexpr Square make_square(File f, Rank r) {
-  return Square((r << 3) + f);
-}
+constexpr Square make_square(File f, Rank r) { return Square((r << 3) + f); }
 
-constexpr Piece make_piece(Color c, PieceType pt) {
-  return Piece((c << 3) + pt);
-}
+constexpr Piece make_piece(Color c, PieceType pt) { return Piece((c << 3) + pt); }
 
-constexpr PieceType type_of(Piece pc) {
-  return PieceType(pc & 7);
-}
+constexpr PieceType type_of(Piece pc) { return PieceType(pc & 7); }
 
 inline Color color_of(Piece pc) {
-  assert(pc != NO_PIECE);
-  return Color(pc >> 3);
+    assert(pc != NO_PIECE);
+    return Color(pc >> 3);
 }
 
-constexpr bool is_ok(Move m) {
-  return m != MOVE_NONE && m != MOVE_NULL;
-}
+constexpr bool is_ok(Square s) { return s >= SQ_A1 && s <= SQ_H8; }
 
-constexpr bool is_ok(Square s) {
-  return s >= SQ_A1 && s <= SQ_H8;
-}
+constexpr File file_of(Square s) { return File(s & 7); }
 
-constexpr File file_of(Square s) {
-  return File(s & 7);
-}
+constexpr Rank rank_of(Square s) { return Rank(s >> 3); }
 
-constexpr Rank rank_of(Square s) {
-  return Rank(s >> 3);
-}
+constexpr Square relative_square(Color c, Square s) { return Square(s ^ (c * 56)); }
 
-constexpr Square relative_square(Color c, Square s) {
-  return Square(s ^ (c * 56));
-}
+constexpr Rank relative_rank(Color c, Rank r) { return Rank(r ^ (c * 7)); }
 
-constexpr Rank relative_rank(Color c, Rank r) {
-  return Rank(r ^ (c * 7));
-}
+constexpr Rank relative_rank(Color c, Square s) { return relative_rank(c, rank_of(s)); }
 
-constexpr Rank relative_rank(Color c, Square s) {
-  return relative_rank(c, rank_of(s));
-}
+constexpr Direction pawn_push(Color c) { return c == WHITE ? NORTH : SOUTH; }
 
-constexpr Direction pawn_push(Color c) {
-  return c == WHITE ? NORTH : SOUTH;
-}
 
-constexpr Square from_sq(Move m) {
-  assert(is_ok(m));
-  return Square((m >> 6) & 0x3F);
-}
-
-constexpr Square to_sq(Move m) {
-  assert(is_ok(m));
-  return Square(m & 0x3F);
-}
-
-constexpr int from_to(Move m) {
-  return m & 0xFFF;
-}
-
-constexpr MoveType type_of(Move m) {
-  return MoveType(m & (3 << 14));
-}
-
-constexpr PieceType promotion_type(Move m) {
-  return PieceType(((m >> 12) & 3) + KNIGHT);
-}
-
-constexpr Move make_move(Square from, Square to) {
-  return Move((from << 6) + to);
-}
-
-template<MoveType T>
-constexpr Move make(Square from, Square to, PieceType pt = KNIGHT) {
-  return Move(T + ((pt - KNIGHT) << 12) + (from << 6) + to);
-}
-
-/// Based on a congruential pseudo random number generator
+// Based on a congruential pseudo-random number generator
 constexpr Key make_key(uint64_t seed) {
-  return seed * 6364136223846793005ULL + 1442695040888963407ULL;
+    return seed * 6364136223846793005ULL + 1442695040888963407ULL;
 }
 
-} // namespace Stockfish
 
-#endif // #ifndef TYPES_H_INCLUDED
+enum MoveType {
+    NORMAL,
+    PROMOTION  = 1 << 14,
+    EN_PASSANT = 2 << 14,
+    CASTLING   = 3 << 14
+};
 
-#include "tune.h" // Global visibility to tuning setup
+// A move needs 16 bits to be stored
+//
+// bit  0- 5: destination square (from 0 to 63)
+// bit  6-11: origin square (from 0 to 63)
+// bit 12-13: promotion piece type - 2 (from KNIGHT-2 to QUEEN-2)
+// bit 14-15: special move flag: promotion (1), en passant (2), castling (3)
+// NOTE: en passant bit is set only when a pawn can be captured
+//
+// Special cases are Move::none() and Move::null(). We can sneak these in because in
+// any normal move destination square is always different from origin square
+// while Move::none() and Move::null() have the same origin and destination square.
+class Move {
+   public:
+    Move() = default;
+    constexpr explicit Move(std::uint16_t d) :
+        data(d) {}
+
+    constexpr Move(Square from, Square to) :
+        data((from << 6) + to) {}
+
+    template<MoveType T>
+    static constexpr Move make(Square from, Square to, PieceType pt = KNIGHT) {
+        return Move(T + ((pt - KNIGHT) << 12) + (from << 6) + to);
+    }
+
+    constexpr Square from_sq() const {
+        assert(is_ok());
+        return Square((data >> 6) & 0x3F);
+    }
+
+    constexpr Square to_sq() const {
+        assert(is_ok());
+        return Square(data & 0x3F);
+    }
+
+    constexpr int from_to() const { return data & 0xFFF; }
+
+    constexpr MoveType type_of() const { return MoveType(data & (3 << 14)); }
+
+    constexpr PieceType promotion_type() const { return PieceType(((data >> 12) & 3) + KNIGHT); }
+
+    constexpr bool is_ok() const { return none().data != data && null().data != data; }
+
+    static constexpr Move null() { return Move(65); }
+    static constexpr Move none() { return Move(0); }
+
+    constexpr bool operator==(const Move& m) const { return data == m.data; }
+    constexpr bool operator!=(const Move& m) const { return data != m.data; }
+
+    constexpr explicit operator bool() const { return data != 0; }
+
+    constexpr std::uint16_t raw() const { return data; }
+
+    struct MoveHash {
+        std::size_t operator()(const Move& m) const { return make_key(m.data); }
+    };
+
+   protected:
+    std::uint16_t data;
+};
+
+}  // namespace Stockfish
+
+#endif  // #ifndef TYPES_H_INCLUDED
+
+#include "tune.h"  // Global visibility to tuning setup

src/uci.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,50 +16,296 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "uci.h"
+
+#include <algorithm>
 #include <cassert>
+#include <cctype>
 #include <cmath>
-#include <iostream>
+#include <cstdlib>
+#include <deque>
+#include <memory>
+#include <optional>
 #include <sstream>
-#include <string>
+#include <vector>
+#include <cstdint>
 
 #include "benchmark.h"
 #include "evaluate.h"
 #include "movegen.h"
+#include "nnue/evaluate_nnue.h"
+#include "nnue/nnue_architecture.h"
 #include "position.h"
 #include "search.h"
-#include "thread.h"
-#include "timeman.h"
-#include "tt.h"
-#include "uci.h"
 #include "syzygy/tbprobe.h"
-#include "nnue/evaluate_nnue.h"
-
-using namespace std;
+#include "types.h"
+#include "ucioption.h"
+#include "perft.h"
 
 namespace Stockfish {
 
-namespace {
+constexpr auto StartFEN             = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
+constexpr int  NormalizeToPawnValue = 356;
+constexpr int  MaxHashMB            = Is64Bit ? 33554432 : 2048;
 
-  // FEN string for the initial position in standard chess
-  const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
+UCI::UCI(int argc, char** argv) :
+    cli(argc, argv) {
+
+    evalFiles = {{Eval::NNUE::Big, {"EvalFile", EvalFileDefaultNameBig, "None", ""}},
+                 {Eval::NNUE::Small, {"EvalFileSmall", EvalFileDefaultNameSmall, "None", ""}}};
 
 
-  // position() is called when the engine receives the "position" UCI command.
-  // It sets up the position that is described in the given FEN string ("fen") or
-  // the initial position ("startpos") and then makes the moves given in the following
-  // move list ("moves").
+    options["Debug Log File"] << Option("", [](const Option& o) { start_logger(o); });
 
-  void position(Position& pos, istringstream& is, StateListPtr& states) {
+    options["Threads"] << Option(1, 1, 1024, [this](const Option&) {
+        threads.set({options, threads, tt});
+    });
 
-    Move m;
-    string token, fen;
+    options["Hash"] << Option(16, 1, MaxHashMB, [this](const Option& o) {
+        threads.main_thread()->wait_for_search_finished();
+        tt.resize(o, options["Threads"]);
+    });
+
+    options["Clear Hash"] << Option([this](const Option&) { search_clear(); });
+    options["Ponder"] << Option(false);
+    options["MultiPV"] << Option(1, 1, MAX_MOVES);
+    options["Skill Level"] << Option(20, 0, 20);
+    options["Move Overhead"] << Option(10, 0, 5000);
+    options["nodestime"] << Option(0, 0, 10000);
+    options["UCI_Chess960"] << Option(false);
+    options["UCI_LimitStrength"] << Option(false);
+    options["UCI_Elo"] << Option(1320, 1320, 3190);
+    options["UCI_ShowWDL"] << Option(false);
+    options["SyzygyPath"] << Option("<empty>", [](const Option& o) { Tablebases::init(o); });
+    options["SyzygyProbeDepth"] << Option(1, 1, 100);
+    options["Syzygy50MoveRule"] << Option(true);
+    options["SyzygyProbeLimit"] << Option(7, 0, 7);
+    options["EvalFile"] << Option(EvalFileDefaultNameBig, [this](const Option&) {
+        evalFiles = Eval::NNUE::load_networks(cli.binaryDirectory, options, evalFiles);
+    });
+    options["EvalFileSmall"] << Option(EvalFileDefaultNameSmall, [this](const Option&) {
+        evalFiles = Eval::NNUE::load_networks(cli.binaryDirectory, options, evalFiles);
+    });
+
+    threads.set({options, threads, tt});
+
+    search_clear();  // After threads are up
+}
+
+void UCI::loop() {
+
+    Position     pos;
+    std::string  token, cmd;
+    StateListPtr states(new std::deque<StateInfo>(1));
+
+    pos.set(StartFEN, false, &states->back());
+
+    for (int i = 1; i < cli.argc; ++i)
+        cmd += std::string(cli.argv[i]) + " ";
+
+    do
+    {
+        if (cli.argc == 1
+            && !getline(std::cin, cmd))  // Wait for an input or an end-of-file (EOF) indication
+            cmd = "quit";
+
+        std::istringstream is(cmd);
+
+        token.clear();  // Avoid a stale if getline() returns nothing or a blank line
+        is >> std::skipws >> token;
+
+        if (token == "quit" || token == "stop")
+            threads.stop = true;
+
+        // The GUI sends 'ponderhit' to tell that the user has played the expected move.
+        // So, 'ponderhit' is sent if pondering was done on the same move that the user
+        // has played. The search should continue, but should also switch from pondering
+        // to the normal search.
+        else if (token == "ponderhit")
+            threads.main_manager()->ponder = false;  // Switch to the normal search
+
+        else if (token == "uci")
+            sync_cout << "id name " << engine_info(true) << "\n"
+                      << options << "\nuciok" << sync_endl;
+
+        else if (token == "setoption")
+            setoption(is);
+        else if (token == "go")
+            go(pos, is, states);
+        else if (token == "position")
+            position(pos, is, states);
+        else if (token == "ucinewgame")
+            search_clear();
+        else if (token == "isready")
+            sync_cout << "readyok" << sync_endl;
+
+        // Add custom non-UCI commands, mainly for debugging purposes.
+        // These commands must not be used during a search!
+        else if (token == "flip")
+            pos.flip();
+        else if (token == "bench")
+            bench(pos, is, states);
+        else if (token == "d")
+            sync_cout << pos << sync_endl;
+        else if (token == "eval")
+            trace_eval(pos);
+        else if (token == "compiler")
+            sync_cout << compiler_info() << sync_endl;
+        else if (token == "export_net")
+        {
+            std::optional<std::string> filename;
+            std::string                f;
+            if (is >> std::skipws >> f)
+                filename = f;
+            Eval::NNUE::save_eval(filename, Eval::NNUE::Big, evalFiles);
+        }
+        else if (token == "--help" || token == "help" || token == "--license" || token == "license")
+            sync_cout
+              << "\nStockfish is a powerful chess engine for playing and analyzing."
+                 "\nIt is released as free software licensed under the GNU GPLv3 License."
+                 "\nStockfish is normally used with a graphical user interface (GUI) and implements"
+                 "\nthe Universal Chess Interface (UCI) protocol to communicate with a GUI, an API, etc."
+                 "\nFor any further information, visit https://github.com/official-stockfish/Stockfish#readme"
+                 "\nor read the corresponding README.md and Copying.txt files distributed along with this program.\n"
+              << sync_endl;
+        else if (!token.empty() && token[0] != '#')
+            sync_cout << "Unknown command: '" << cmd << "'. Type help for more information."
+                      << sync_endl;
+
+    } while (token != "quit" && cli.argc == 1);  // The command-line arguments are one-shot
+}
+
+void UCI::go(Position& pos, std::istringstream& is, StateListPtr& states) {
+
+    Search::LimitsType limits;
+    std::string        token;
+    bool               ponderMode = false;
+
+    limits.startTime = now();  // The search starts as early as possible
+
+    while (is >> token)
+        if (token == "searchmoves")  // Needs to be the last command on the line
+            while (is >> token)
+                limits.searchmoves.push_back(to_move(pos, token));
+
+        else if (token == "wtime")
+            is >> limits.time[WHITE];
+        else if (token == "btime")
+            is >> limits.time[BLACK];
+        else if (token == "winc")
+            is >> limits.inc[WHITE];
+        else if (token == "binc")
+            is >> limits.inc[BLACK];
+        else if (token == "movestogo")
+            is >> limits.movestogo;
+        else if (token == "depth")
+            is >> limits.depth;
+        else if (token == "nodes")
+            is >> limits.nodes;
+        else if (token == "movetime")
+            is >> limits.movetime;
+        else if (token == "mate")
+            is >> limits.mate;
+        else if (token == "perft")
+            is >> limits.perft;
+        else if (token == "infinite")
+            limits.infinite = 1;
+        else if (token == "ponder")
+            ponderMode = true;
+
+    Eval::NNUE::verify(options, evalFiles);
+
+    if (limits.perft)
+    {
+        perft(pos.fen(), limits.perft, options["UCI_Chess960"]);
+        return;
+    }
+
+    threads.start_thinking(options, pos, states, limits, ponderMode);
+}
+
+void UCI::bench(Position& pos, std::istream& args, StateListPtr& states) {
+    std::string token;
+    uint64_t    num, nodes = 0, cnt = 1;
+
+    std::vector<std::string> list = setup_bench(pos, args);
+
+    num = count_if(list.begin(), list.end(),
+                   [](const std::string& s) { return s.find("go ") == 0 || s.find("eval") == 0; });
+
+    TimePoint elapsed = now();
+
+    for (const auto& cmd : list)
+    {
+        std::istringstream is(cmd);
+        is >> std::skipws >> token;
+
+        if (token == "go" || token == "eval")
+        {
+            std::cerr << "\nPosition: " << cnt++ << '/' << num << " (" << pos.fen() << ")"
+                      << std::endl;
+            if (token == "go")
+            {
+                go(pos, is, states);
+                threads.main_thread()->wait_for_search_finished();
+                nodes += threads.nodes_searched();
+            }
+            else
+                trace_eval(pos);
+        }
+        else if (token == "setoption")
+            setoption(is);
+        else if (token == "position")
+            position(pos, is, states);
+        else if (token == "ucinewgame")
+        {
+            search_clear();  // Search::clear() may take a while
+            elapsed = now();
+        }
+    }
+
+    elapsed = now() - elapsed + 1;  // Ensure positivity to avoid a 'divide by zero'
+
+    dbg_print();
+
+    std::cerr << "\n==========================="
+              << "\nTotal time (ms) : " << elapsed << "\nNodes searched  : " << nodes
+              << "\nNodes/second    : " << 1000 * nodes / elapsed << std::endl;
+}
+
+void UCI::trace_eval(Position& pos) {
+    StateListPtr states(new std::deque<StateInfo>(1));
+    Position     p;
+    p.set(pos.fen(), options["UCI_Chess960"], &states->back());
+
+    Eval::NNUE::verify(options, evalFiles);
+
+    sync_cout << "\n" << Eval::trace(p) << sync_endl;
+}
+
+void UCI::search_clear() {
+    threads.main_thread()->wait_for_search_finished();
+
+    tt.clear(options["Threads"]);
+    threads.clear();
+    Tablebases::init(options["SyzygyPath"]);  // Free mapped files
+}
+
+void UCI::setoption(std::istringstream& is) {
+    threads.main_thread()->wait_for_search_finished();
+    options.setoption(is);
+}
+
+void UCI::position(Position& pos, std::istringstream& is, StateListPtr& states) {
+    Move        m;
+    std::string token, fen;
 
     is >> token;
 
     if (token == "startpos")
     {
         fen = StartFEN;
-        is >> token; // Consume the "moves" token, if any
+        is >> token;  // Consume the "moves" token, if any
     }
     else if (token == "fen")
         while (is >> token && token != "moves")
@@ -67,332 +313,107 @@ namespace {
     else
         return;
 
-    states = StateListPtr(new std::deque<StateInfo>(1)); // Drop the old state and create a new one
-    pos.set(fen, Options["UCI_Chess960"], &states->back(), Threads.main());
+    states = StateListPtr(new std::deque<StateInfo>(1));  // Drop the old state and create a new one
+    pos.set(fen, options["UCI_Chess960"], &states->back());
 
     // Parse the move list, if any
-    while (is >> token && (m = UCI::to_move(pos, token)) != MOVE_NONE)
+    while (is >> token && (m = to_move(pos, token)) != Move::none())
     {
         states->emplace_back();
         pos.do_move(m, states->back());
     }
-  }
+}
 
-  // trace_eval() prints the evaluation of the current position, consistent with
-  // the UCI options set so far.
+int UCI::to_cp(Value v) { return 100 * v / NormalizeToPawnValue; }
 
-  void trace_eval(Position& pos) {
+std::string UCI::value(Value v) {
+    assert(-VALUE_INFINITE < v && v < VALUE_INFINITE);
 
-    StateListPtr states(new std::deque<StateInfo>(1));
-    Position p;
-    p.set(pos.fen(), Options["UCI_Chess960"], &states->back(), Threads.main());
+    std::stringstream ss;
 
-    Eval::NNUE::verify();
-
-    sync_cout << "\n" << Eval::trace(p) << sync_endl;
-  }
-
-
-  // setoption() is called when the engine receives the "setoption" UCI command.
-  // The function updates the UCI option ("name") to the given value ("value").
-
-  void setoption(istringstream& is) {
-
-    string token, name, value;
-
-    is >> token; // Consume the "name" token
-
-    // Read the option name (can contain spaces)
-    while (is >> token && token != "value")
-        name += (name.empty() ? "" : " ") + token;
-
-    // Read the option value (can contain spaces)
-    while (is >> token)
-        value += (value.empty() ? "" : " ") + token;
-
-    if (Options.count(name))
-        Options[name] = value;
-    else
-        sync_cout << "No such option: " << name << sync_endl;
-  }
-
-
-  // go() is called when the engine receives the "go" UCI command. The function
-  // sets the thinking time and other parameters from the input string, then starts
-  // with a search.
-
-  void go(Position& pos, istringstream& is, StateListPtr& states) {
-
-    Search::LimitsType limits;
-    string token;
-    bool ponderMode = false;
-
-    limits.startTime = now(); // The search starts as early as possible
-
-    while (is >> token)
-        if (token == "searchmoves") // Needs to be the last command on the line
-            while (is >> token)
-                limits.searchmoves.push_back(UCI::to_move(pos, token));
-
-        else if (token == "wtime")     is >> limits.time[WHITE];
-        else if (token == "btime")     is >> limits.time[BLACK];
-        else if (token == "winc")      is >> limits.inc[WHITE];
-        else if (token == "binc")      is >> limits.inc[BLACK];
-        else if (token == "movestogo") is >> limits.movestogo;
-        else if (token == "depth")     is >> limits.depth;
-        else if (token == "nodes")     is >> limits.nodes;
-        else if (token == "movetime")  is >> limits.movetime;
-        else if (token == "mate")      is >> limits.mate;
-        else if (token == "perft")     is >> limits.perft;
-        else if (token == "infinite")  limits.infinite = 1;
-        else if (token == "ponder")    ponderMode = true;
-
-    Threads.start_thinking(pos, states, limits, ponderMode);
-  }
-
-
-  // bench() is called when the engine receives the "bench" command.
-  // Firstly, a list of UCI commands is set up according to the bench
-  // parameters, then it is run one by one, printing a summary at the end.
-
-  void bench(Position& pos, istream& args, StateListPtr& states) {
-
-    string token;
-    uint64_t num, nodes = 0, cnt = 1;
-
-    vector<string> list = setup_bench(pos, args);
-    num = count_if(list.begin(), list.end(), [](const string& s) { return s.find("go ") == 0 || s.find("eval") == 0; });
-
-    TimePoint elapsed = now();
-
-    for (const auto& cmd : list)
+    if (std::abs(v) < VALUE_TB_WIN_IN_MAX_PLY)
+        ss << "cp " << to_cp(v);
+    else if (std::abs(v) <= VALUE_TB)
     {
-        istringstream is(cmd);
-        is >> skipws >> token;
-
-        if (token == "go" || token == "eval")
-        {
-            cerr << "\nPosition: " << cnt++ << '/' << num << " (" << pos.fen() << ")" << endl;
-            if (token == "go")
-            {
-               go(pos, is, states);
-               Threads.main()->wait_for_search_finished();
-               nodes += Threads.nodes_searched();
-            }
-            else
-               trace_eval(pos);
-        }
-        else if (token == "setoption")  setoption(is);
-        else if (token == "position")   position(pos, is, states);
-        else if (token == "ucinewgame") { Search::clear(); elapsed = now(); } // Search::clear() may take a while
+        const int ply = VALUE_TB - std::abs(v);  // recompute ss->ply
+        ss << "cp " << (v > 0 ? 20000 - ply : -20000 + ply);
     }
+    else
+        ss << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
 
-    elapsed = now() - elapsed + 1; // Ensure positivity to avoid a 'divide by zero'
-
-    dbg_print();
-
-    cerr << "\n==========================="
-         << "\nTotal time (ms) : " << elapsed
-         << "\nNodes searched  : " << nodes
-         << "\nNodes/second    : " << 1000 * nodes / elapsed << endl;
-  }
-
-  // The win rate model returns the probability of winning (in per mille units) given an
-  // eval and a game ply. It fits the LTC fishtest statistics rather accurately.
-  int win_rate_model(Value v, int ply) {
-
-     // The model only captures up to 240 plies, so limit the input and then rescale
-     double m = std::min(240, ply) / 64.0;
-
-     // The coefficients of a third-order polynomial fit is based on the fishtest data
-     // for two parameters that need to transform eval to the argument of a logistic
-     // function.
-     constexpr double as[] = {   0.38036525,   -2.82015070,   23.17882135,  307.36768407};
-     constexpr double bs[] = {  -2.29434733,   13.27689788,  -14.26828904,   63.45318330 };
-
-     // Enforce that NormalizeToPawnValue corresponds to a 50% win rate at ply 64
-     static_assert(UCI::NormalizeToPawnValue == int(as[0] + as[1] + as[2] + as[3]));
-
-     double a = (((as[0] * m + as[1]) * m + as[2]) * m) + as[3];
-     double b = (((bs[0] * m + bs[1]) * m + bs[2]) * m) + bs[3];
-
-     // Transform the eval to centipawns with limited range
-     double x = std::clamp(double(v), -4000.0, 4000.0);
-
-     // Return the win rate in per mille units rounded to the nearest value
-     return int(0.5 + 1000 / (1 + std::exp((a - x) / b)));
-  }
-
-} // namespace
-
-
-/// UCI::loop() waits for a command from the stdin, parses it and then calls the appropriate
-/// function. It also intercepts an end-of-file (EOF) indication from the stdin to ensure a
-/// graceful exit if the GUI dies unexpectedly. When called with some command-line arguments,
-/// like running 'bench', the function returns immediately after the command is executed.
-/// In addition to the UCI ones, some additional debug commands are also supported.
-
-void UCI::loop(int argc, char* argv[]) {
-
-  Position pos;
-  string token, cmd;
-  StateListPtr states(new std::deque<StateInfo>(1));
-
-  pos.set(StartFEN, false, &states->back(), Threads.main());
-
-  for (int i = 1; i < argc; ++i)
-      cmd += std::string(argv[i]) + " ";
-
-  do {
-      if (argc == 1 && !getline(cin, cmd)) // Wait for an input or an end-of-file (EOF) indication
-          cmd = "quit";
-
-      istringstream is(cmd);
-
-      token.clear(); // Avoid a stale if getline() returns nothing or a blank line
-      is >> skipws >> token;
-
-      if (    token == "quit"
-          ||  token == "stop")
-          Threads.stop = true;
-
-      // The GUI sends 'ponderhit' to tell that the user has played the expected move.
-      // So, 'ponderhit' is sent if pondering was done on the same move that the user
-      // has played. The search should continue, but should also switch from pondering
-      // to the normal search.
-      else if (token == "ponderhit")
-          Threads.main()->ponder = false; // Switch to the normal search
-
-      else if (token == "uci")
-          sync_cout << "id name " << engine_info(true)
-                    << "\n"       << Options
-                    << "\nuciok"  << sync_endl;
-
-      else if (token == "setoption")  setoption(is);
-      else if (token == "go")         go(pos, is, states);
-      else if (token == "position")   position(pos, is, states);
-      else if (token == "ucinewgame") Search::clear();
-      else if (token == "isready")    sync_cout << "readyok" << sync_endl;
-
-      // Add custom non-UCI commands, mainly for debugging purposes.
-      // These commands must not be used during a search!
-      else if (token == "flip")     pos.flip();
-      else if (token == "bench")    bench(pos, is, states);
-      else if (token == "d")        sync_cout << pos << sync_endl;
-      else if (token == "eval")     trace_eval(pos);
-      else if (token == "compiler") sync_cout << compiler_info() << sync_endl;
-      else if (token == "export_net")
-      {
-          std::optional<std::string> filename;
-          std::string f;
-          if (is >> skipws >> f)
-              filename = f;
-          Eval::NNUE::save_eval(filename);
-      }
-      else if (token == "--help" || token == "help" || token == "--license" || token == "license")
-          sync_cout << "\nStockfish is a powerful chess engine for playing and analyzing."
-                       "\nIt is released as free software licensed under the GNU GPLv3 License."
-                       "\nStockfish is normally used with a graphical user interface (GUI) and implements"
-                       "\nthe Universal Chess Interface (UCI) protocol to communicate with a GUI, an API, etc."
-                       "\nFor any further information, visit https://github.com/official-stockfish/Stockfish#readme"
-                       "\nor read the corresponding README.md and Copying.txt files distributed along with this program.\n" << sync_endl;
-      else if (!token.empty() && token[0] != '#')
-          sync_cout << "Unknown command: '" << cmd << "'. Type help for more information." << sync_endl;
-
-  } while (token != "quit" && argc == 1); // The command-line arguments are one-shot
+    return ss.str();
 }
 
-
-/// UCI::value() converts a Value to a string by adhering to the UCI protocol specification:
-///
-/// cp <x>    The score from the engine's point of view in centipawns.
-/// mate <y>  Mate in 'y' moves (not plies). If the engine is getting mated,
-///           uses negative values for 'y'.
-
-string UCI::value(Value v) {
-
-  assert(-VALUE_INFINITE < v && v < VALUE_INFINITE);
-
-  stringstream ss;
-
-  if (abs(v) < VALUE_TB_WIN_IN_MAX_PLY)
-      ss << "cp " << v * 100 / NormalizeToPawnValue;
-  else if (abs(v) < VALUE_MATE_IN_MAX_PLY)
-  {
-      const int ply = VALUE_MATE_IN_MAX_PLY - 1 - std::abs(v);  // recompute ss->ply
-      ss << "cp " << (v > 0 ? 20000 - ply : -20000 + ply);
-  }
-  else
-      ss << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
-
-  return ss.str();
-}
-
-
-/// UCI::wdl() reports the win-draw-loss (WDL) statistics given an evaluation
-/// and a game ply based on the data gathered for fishtest LTC games.
-
-string UCI::wdl(Value v, int ply) {
-
-  stringstream ss;
-
-  int wdl_w = win_rate_model( v, ply);
-  int wdl_l = win_rate_model(-v, ply);
-  int wdl_d = 1000 - wdl_w - wdl_l;
-  ss << " wdl " << wdl_w << " " << wdl_d << " " << wdl_l;
-
-  return ss.str();
-}
-
-
-/// UCI::square() converts a Square to a string in algebraic notation (g1, a7, etc.)
-
 std::string UCI::square(Square s) {
-  return std::string{ char('a' + file_of(s)), char('1' + rank_of(s)) };
+    return std::string{char('a' + file_of(s)), char('1' + rank_of(s))};
 }
 
+std::string UCI::move(Move m, bool chess960) {
+    if (m == Move::none())
+        return "(none)";
 
-/// UCI::move() converts a Move to a string in coordinate notation (g1f3, a7a8q).
-/// The only special case is castling where the e1g1 notation is printed in
-/// standard chess mode and in e1h1 notation it is printed in Chess960 mode.
-/// Internally, all castling moves are always encoded as 'king captures rook'.
+    if (m == Move::null())
+        return "0000";
 
-string UCI::move(Move m, bool chess960) {
+    Square from = m.from_sq();
+    Square to   = m.to_sq();
 
-  if (m == MOVE_NONE)
-      return "(none)";
+    if (m.type_of() == CASTLING && !chess960)
+        to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
 
-  if (m == MOVE_NULL)
-      return "0000";
+    std::string move = square(from) + square(to);
 
-  Square from = from_sq(m);
-  Square to = to_sq(m);
+    if (m.type_of() == PROMOTION)
+        move += " pnbrqk"[m.promotion_type()];
 
-  if (type_of(m) == CASTLING && !chess960)
-      to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
-
-  string move = UCI::square(from) + UCI::square(to);
-
-  if (type_of(m) == PROMOTION)
-      move += " pnbrqk"[promotion_type(m)];
-
-  return move;
+    return move;
 }
 
+namespace {
+// The win rate model returns the probability of winning (in per mille units) given an
+// eval and a game ply. It fits the LTC fishtest statistics rather accurately.
+int win_rate_model(Value v, int ply) {
 
-/// UCI::to_move() converts a string representing a move in coordinate notation
-/// (g1f3, a7a8q) to the corresponding legal Move, if any.
+    // The fitted model only uses data for moves in [8, 120], and is anchored at move 32.
+    double m = std::clamp(ply / 2 + 1, 8, 120) / 32.0;
 
-Move UCI::to_move(const Position& pos, string& str) {
+    // The coefficients of a third-order polynomial fit is based on the fishtest data
+    // for two parameters that need to transform eval to the argument of a logistic
+    // function.
+    constexpr double as[] = {-1.06249702, 7.42016937, 0.89425629, 348.60356174};
+    constexpr double bs[] = {-5.33122190, 39.57831533, -90.84473771, 123.40620748};
 
-  if (str.length() == 5)
-      str[4] = char(tolower(str[4])); // The promotion piece character must be lowercased
+    // Enforce that NormalizeToPawnValue corresponds to a 50% win rate at move 32.
+    static_assert(NormalizeToPawnValue == int(0.5 + as[0] + as[1] + as[2] + as[3]));
 
-  for (const auto& m : MoveList<LEGAL>(pos))
-      if (str == UCI::move(m, pos.is_chess960()))
-          return m;
+    double a = (((as[0] * m + as[1]) * m + as[2]) * m) + as[3];
+    double b = (((bs[0] * m + bs[1]) * m + bs[2]) * m) + bs[3];
 
-  return MOVE_NONE;
+    // Return the win rate in per mille units, rounded to the nearest integer.
+    return int(0.5 + 1000 / (1 + std::exp((a - double(v)) / b)));
+}
 }
 
-} // namespace Stockfish
+std::string UCI::wdl(Value v, int ply) {
+    std::stringstream ss;
+
+    int wdl_w = win_rate_model(v, ply);
+    int wdl_l = win_rate_model(-v, ply);
+    int wdl_d = 1000 - wdl_w - wdl_l;
+    ss << " wdl " << wdl_w << " " << wdl_d << " " << wdl_l;
+
+    return ss.str();
+}
+
+Move UCI::to_move(const Position& pos, std::string& str) {
+    if (str.length() == 5)
+        str[4] = char(tolower(str[4]));  // The promotion piece character must be lowercased
+
+    for (const auto& m : MoveList<LEGAL>(pos))
+        if (str == move(m, pos.is_chess960()))
+            return m;
+
+    return Move::none();
+}
+
+}  // namespace Stockfish

src/uci.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,74 +19,59 @@
 #ifndef UCI_H_INCLUDED
 #define UCI_H_INCLUDED
 
-#include <map>
+#include <iostream>
 #include <string>
+#include <unordered_map>
 
-#include "types.h"
+#include "evaluate.h"
+#include "misc.h"
+#include "position.h"
+#include "thread.h"
+#include "tt.h"
+#include "ucioption.h"
 
 namespace Stockfish {
 
-class Position;
+namespace Eval::NNUE {
+enum NetSize : int;
+}
 
-namespace UCI {
+class Move;
+enum Square : int;
+using Value = int;
 
-// Normalizes the internal value as reported by evaluate or search
-// to the UCI centipawn result used in output. This value is derived from
-// the win_rate_model() such that Stockfish outputs an advantage of
-// "100 centipawns" for a position if the engine has a 50% probability to win
-// from this position in selfplay at fishtest LTC time control.
-const int NormalizeToPawnValue = 328;
+class UCI {
+   public:
+    UCI(int argc, char** argv);
 
-class Option;
+    void loop();
 
-/// Define a custom comparator, because the UCI options should be case-insensitive
-struct CaseInsensitiveLess {
-  bool operator() (const std::string&, const std::string&) const;
+    static int         to_cp(Value v);
+    static std::string value(Value v);
+    static std::string square(Square s);
+    static std::string move(Move m, bool chess960);
+    static std::string wdl(Value v, int ply);
+    static Move        to_move(const Position& pos, std::string& str);
+
+    const std::string& workingDirectory() const { return cli.workingDirectory; }
+
+    OptionsMap options;
+
+    std::unordered_map<Eval::NNUE::NetSize, Eval::EvalFile> evalFiles;
+
+   private:
+    TranspositionTable tt;
+    ThreadPool         threads;
+    CommandLine        cli;
+
+    void go(Position& pos, std::istringstream& is, StateListPtr& states);
+    void bench(Position& pos, std::istream& args, StateListPtr& states);
+    void position(Position& pos, std::istringstream& is, StateListPtr& states);
+    void trace_eval(Position& pos);
+    void search_clear();
+    void setoption(std::istringstream& is);
 };
 
-/// The options container is defined as a std::map
-using OptionsMap = std::map<std::string, Option, CaseInsensitiveLess>;
+}  // namespace Stockfish
 
-/// The Option class implements each option as specified by the UCI protocol
-class Option {
-
-  using OnChange = void (*)(const Option&);
-
-public:
-  Option(OnChange = nullptr);
-  Option(bool v, OnChange = nullptr);
-  Option(const char* v, OnChange = nullptr);
-  Option(double v, int minv, int maxv, OnChange = nullptr);
-  Option(const char* v, const char* cur, OnChange = nullptr);
-
-  Option& operator=(const std::string&);
-  void operator<<(const Option&);
-  operator int() const;
-  operator std::string() const;
-  bool operator==(const char*) const;
-
-private:
-  friend std::ostream& operator<<(std::ostream&, const OptionsMap&);
-
-  std::string defaultValue, currentValue, type;
-  int min, max;
-  size_t idx;
-  OnChange on_change;
-};
-
-void init(OptionsMap&);
-void loop(int argc, char* argv[]);
-std::string value(Value v);
-std::string square(Square s);
-std::string move(Move m, bool chess960);
-std::string pv(const Position& pos, Depth depth);
-std::string wdl(Value v, int ply);
-Move to_move(const Position& pos, std::string& str);
-
-} // namespace UCI
-
-extern UCI::OptionsMap Options;
-
-} // namespace Stockfish
-
-#endif // #ifndef UCI_H_INCLUDED
+#endif  // #ifndef UCI_H_INCLUDED

src/ucioption.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -16,179 +16,170 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "ucioption.h"
+
 #include <algorithm>
 #include <cassert>
-#include <ostream>
+#include <cctype>
+#include <iostream>
 #include <sstream>
+#include <utility>
 
-#include "evaluate.h"
 #include "misc.h"
-#include "search.h"
-#include "thread.h"
-#include "tt.h"
-#include "uci.h"
-#include "syzygy/tbprobe.h"
-
-using std::string;
 
 namespace Stockfish {
 
-UCI::OptionsMap Options; // Global object
+bool CaseInsensitiveLess::operator()(const std::string& s1, const std::string& s2) const {
 
-namespace UCI {
-
-/// 'On change' actions, triggered by an option's value change
-static void on_clear_hash(const Option&) { Search::clear(); }
-static void on_hash_size(const Option& o) { TT.resize(size_t(o)); }
-static void on_logger(const Option& o) { start_logger(o); }
-static void on_threads(const Option& o) { Threads.set(size_t(o)); }
-static void on_tb_path(const Option& o) { Tablebases::init(o); }
-static void on_use_NNUE(const Option&) { Eval::NNUE::init(); }
-static void on_eval_file(const Option&) { Eval::NNUE::init(); }
-
-/// Our case insensitive less() function as required by UCI protocol
-bool CaseInsensitiveLess::operator() (const string& s1, const string& s2) const {
-
-  return std::lexicographical_compare(s1.begin(), s1.end(), s2.begin(), s2.end(),
-         [](char c1, char c2) { return tolower(c1) < tolower(c2); });
+    return std::lexicographical_compare(
+      s1.begin(), s1.end(), s2.begin(), s2.end(),
+      [](char c1, char c2) { return std::tolower(c1) < std::tolower(c2); });
 }
 
+void OptionsMap::setoption(std::istringstream& is) {
+    std::string token, name, value;
 
-/// UCI::init() initializes the UCI options to their hard-coded default values
+    is >> token;  // Consume the "name" token
 
-void init(OptionsMap& o) {
+    // Read the option name (can contain spaces)
+    while (is >> token && token != "value")
+        name += (name.empty() ? "" : " ") + token;
 
-  constexpr int MaxHashMB = Is64Bit ? 33554432 : 2048;
+    // Read the option value (can contain spaces)
+    while (is >> token)
+        value += (value.empty() ? "" : " ") + token;
 
-  o["Debug Log File"]        << Option("", on_logger);
-  o["Threads"]               << Option(1, 1, 1024, on_threads);
-  o["Hash"]                  << Option(16, 1, MaxHashMB, on_hash_size);
-  o["Clear Hash"]            << Option(on_clear_hash);
-  o["Ponder"]                << Option(false);
-  o["MultiPV"]               << Option(1, 1, 500);
-  o["Skill Level"]           << Option(20, 0, 20);
-  o["Move Overhead"]         << Option(10, 0, 5000);
-  o["Slow Mover"]            << Option(100, 10, 1000);
-  o["nodestime"]             << Option(0, 0, 10000);
-  o["UCI_Chess960"]          << Option(false);
-  o["UCI_AnalyseMode"]       << Option(false);
-  o["UCI_LimitStrength"]     << Option(false);
-  o["UCI_Elo"]               << Option(1320, 1320, 3190);
-  o["UCI_ShowWDL"]           << Option(false);
-  o["SyzygyPath"]            << Option("<empty>", on_tb_path);
-  o["SyzygyProbeDepth"]      << Option(1, 1, 100);
-  o["Syzygy50MoveRule"]      << Option(true);
-  o["SyzygyProbeLimit"]      << Option(7, 0, 7);
-  o["Use NNUE"]              << Option(true, on_use_NNUE);
-  o["EvalFile"]              << Option(EvalFileDefaultName, on_eval_file);
+    if (options_map.count(name))
+        options_map[name] = value;
+    else
+        sync_cout << "No such option: " << name << sync_endl;
 }
 
-
-/// operator<<() is used to print all the options default values in chronological
-/// insertion order (the idx field) and in the format defined by the UCI protocol.
-
-std::ostream& operator<<(std::ostream& os, const OptionsMap& om) {
-
-  for (size_t idx = 0; idx < om.size(); ++idx)
-      for (const auto& it : om)
-          if (it.second.idx == idx)
-          {
-              const Option& o = it.second;
-              os << "\noption name " << it.first << " type " << o.type;
-
-              if (o.type == "string" || o.type == "check" || o.type == "combo")
-                  os << " default " << o.defaultValue;
-
-              if (o.type == "spin")
-                  os << " default " << int(stof(o.defaultValue))
-                     << " min "     << o.min
-                     << " max "     << o.max;
-
-              break;
-          }
-
-  return os;
+Option OptionsMap::operator[](const std::string& name) const {
+    auto it = options_map.find(name);
+    return it != options_map.end() ? it->second : Option();
 }
 
+Option& OptionsMap::operator[](const std::string& name) { return options_map[name]; }
 
-/// Option class constructors and conversion operators
+std::size_t OptionsMap::count(const std::string& name) const { return options_map.count(name); }
 
-Option::Option(const char* v, OnChange f) : type("string"), min(0), max(0), on_change(f)
-{ defaultValue = currentValue = v; }
+Option::Option(const char* v, OnChange f) :
+    type("string"),
+    min(0),
+    max(0),
+    on_change(std::move(f)) {
+    defaultValue = currentValue = v;
+}
 
-Option::Option(bool v, OnChange f) : type("check"), min(0), max(0), on_change(f)
-{ defaultValue = currentValue = (v ? "true" : "false"); }
+Option::Option(bool v, OnChange f) :
+    type("check"),
+    min(0),
+    max(0),
+    on_change(std::move(f)) {
+    defaultValue = currentValue = (v ? "true" : "false");
+}
 
-Option::Option(OnChange f) : type("button"), min(0), max(0), on_change(f)
-{}
+Option::Option(OnChange f) :
+    type("button"),
+    min(0),
+    max(0),
+    on_change(std::move(f)) {}
 
-Option::Option(double v, int minv, int maxv, OnChange f) : type("spin"), min(minv), max(maxv), on_change(f)
-{ defaultValue = currentValue = std::to_string(v); }
+Option::Option(double v, int minv, int maxv, OnChange f) :
+    type("spin"),
+    min(minv),
+    max(maxv),
+    on_change(std::move(f)) {
+    defaultValue = currentValue = std::to_string(v);
+}
 
-Option::Option(const char* v, const char* cur, OnChange f) : type("combo"), min(0), max(0), on_change(f)
-{ defaultValue = v; currentValue = cur; }
+Option::Option(const char* v, const char* cur, OnChange f) :
+    type("combo"),
+    min(0),
+    max(0),
+    on_change(std::move(f)) {
+    defaultValue = v;
+    currentValue = cur;
+}
 
 Option::operator int() const {
-  assert(type == "check" || type == "spin");
-  return (type == "spin" ? std::stoi(currentValue) : currentValue == "true");
+    assert(type == "check" || type == "spin");
+    return (type == "spin" ? std::stoi(currentValue) : currentValue == "true");
 }
 
 Option::operator std::string() const {
-  assert(type == "string");
-  return currentValue;
+    assert(type == "string");
+    return currentValue;
 }
 
 bool Option::operator==(const char* s) const {
-  assert(type == "combo");
-  return   !CaseInsensitiveLess()(currentValue, s)
-        && !CaseInsensitiveLess()(s, currentValue);
+    assert(type == "combo");
+    return !CaseInsensitiveLess()(currentValue, s) && !CaseInsensitiveLess()(s, currentValue);
 }
 
 
-/// operator<<() inits options and assigns idx in the correct printing order
+// Inits options and assigns idx in the correct printing order
 
 void Option::operator<<(const Option& o) {
 
-  static size_t insert_order = 0;
+    static size_t insert_order = 0;
 
-  *this = o;
-  idx = insert_order++;
+    *this = o;
+    idx   = insert_order++;
 }
 
 
-/// operator=() updates currentValue and triggers on_change() action. It's up to
-/// the GUI to check for option's limits, but we could receive the new value
-/// from the user by console window, so let's check the bounds anyway.
+// Updates currentValue and triggers on_change() action. It's up to
+// the GUI to check for option's limits, but we could receive the new value
+// from the user by console window, so let's check the bounds anyway.
+Option& Option::operator=(const std::string& v) {
 
-Option& Option::operator=(const string& v) {
+    assert(!type.empty());
 
-  assert(!type.empty());
+    if ((type != "button" && type != "string" && v.empty())
+        || (type == "check" && v != "true" && v != "false")
+        || (type == "spin" && (std::stof(v) < min || std::stof(v) > max)))
+        return *this;
 
-  if (   (type != "button" && type != "string" && v.empty())
-      || (type == "check" && v != "true" && v != "false")
-      || (type == "spin" && (stof(v) < min || stof(v) > max)))
-      return *this;
+    if (type == "combo")
+    {
+        OptionsMap         comboMap;  // To have case insensitive compare
+        std::string        token;
+        std::istringstream ss(defaultValue);
+        while (ss >> token)
+            comboMap[token] << Option();
+        if (!comboMap.count(v) || v == "var")
+            return *this;
+    }
 
-  if (type == "combo")
-  {
-      OptionsMap comboMap; // To have case insensitive compare
-      string token;
-      std::istringstream ss(defaultValue);
-      while (ss >> token)
-          comboMap[token] << Option();
-      if (!comboMap.count(v) || v == "var")
-          return *this;
-  }
+    if (type != "button")
+        currentValue = v;
 
-  if (type != "button")
-      currentValue = v;
+    if (on_change)
+        on_change(*this);
 
-  if (on_change)
-      on_change(*this);
-
-  return *this;
+    return *this;
 }
 
-} // namespace UCI
+std::ostream& operator<<(std::ostream& os, const OptionsMap& om) {
+    for (size_t idx = 0; idx < om.options_map.size(); ++idx)
+        for (const auto& it : om.options_map)
+            if (it.second.idx == idx)
+            {
+                const Option& o = it.second;
+                os << "\noption name " << it.first << " type " << o.type;
 
-} // namespace Stockfish
+                if (o.type == "string" || o.type == "check" || o.type == "combo")
+                    os << " default " << o.defaultValue;
+
+                if (o.type == "spin")
+                    os << " default " << int(stof(o.defaultValue)) << " min " << o.min << " max "
+                       << o.max;
+
+                break;
+            }
+
+    return os;
+}
+}

src/ucioption.h

@@ -0,0 +1,81 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2024 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef UCIOPTION_H_INCLUDED
+#define UCIOPTION_H_INCLUDED
+
+#include <cstddef>
+#include <functional>
+#include <iosfwd>
+#include <map>
+#include <string>
+
+namespace Stockfish {
+// Define a custom comparator, because the UCI options should be case-insensitive
+struct CaseInsensitiveLess {
+    bool operator()(const std::string&, const std::string&) const;
+};
+
+class Option;
+
+class OptionsMap {
+   public:
+    void setoption(std::istringstream&);
+
+    friend std::ostream& operator<<(std::ostream&, const OptionsMap&);
+
+    Option  operator[](const std::string&) const;
+    Option& operator[](const std::string&);
+
+    std::size_t count(const std::string&) const;
+
+   private:
+    // The options container is defined as a std::map
+    using OptionsStore = std::map<std::string, Option, CaseInsensitiveLess>;
+
+    OptionsStore options_map;
+};
+
+// The Option class implements each option as specified by the UCI protocol
+class Option {
+   public:
+    using OnChange = std::function<void(const Option&)>;
+
+    Option(OnChange = nullptr);
+    Option(bool v, OnChange = nullptr);
+    Option(const char* v, OnChange = nullptr);
+    Option(double v, int minv, int maxv, OnChange = nullptr);
+    Option(const char* v, const char* cur, OnChange = nullptr);
+
+    Option& operator=(const std::string&);
+    void    operator<<(const Option&);
+    operator int() const;
+    operator std::string() const;
+    bool operator==(const char*) const;
+
+    friend std::ostream& operator<<(std::ostream&, const OptionsMap&);
+
+   private:
+    std::string defaultValue, currentValue, type;
+    int         min, max;
+    size_t      idx;
+    OnChange    on_change;
+};
+
+}
+#endif  // #ifndef UCIOPTION_H_INCLUDED

tests/instrumented.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# check for errors under valgrind or sanitizers.
+# check for errors under Valgrind or sanitizers.
 
 error()
 {
@@ -64,14 +64,32 @@ EOF
   ;;
 esac
 
+cat << EOF > bench_tmp.epd
+Rn6/1rbq1bk1/2p2n1p/2Bp1p2/3Pp1pP/1N2P1P1/2Q1NPB1/6K1 w - - 2 26
+rnbqkb1r/ppp1pp2/5n1p/3p2p1/P2PP3/5P2/1PP3PP/RNBQKBNR w KQkq - 0 3
+3qnrk1/4bp1p/1p2p1pP/p2bN3/1P1P1B2/P2BQ3/5PP1/4R1K1 w - - 9 28
+r4rk1/1b2ppbp/pq4pn/2pp1PB1/1p2P3/1P1P1NN1/1PP3PP/R2Q1RK1 w - - 0 13
+EOF
+
 # simple command line testing
 for args in "eval" \
             "go nodes 1000" \
             "go depth 10" \
+            "go perft 4" \
             "go movetime 1000" \
             "go wtime 8000 btime 8000 winc 500 binc 500" \
+            "go wtime 1000 btime 1000 winc 0 binc 0" \
+            "go wtime 1000 btime 1000 winc 0 binc 0" \
+            "go wtime 1000 btime 1000 winc 0 binc 0 movestogo 5" \
+            "go movetime 200" \
+            "go nodes 20000 searchmoves e2e4 d2d4" \
             "bench 128 $threads 8 default depth" \
-            "export_net verify.nnue"
+            "bench 128 $threads 3 bench_tmp.epd depth" \
+            "export_net verify.nnue" \
+            "d" \
+            "compiler" \
+            "license" \
+            "uci"
 do
 
    echo "$prefix $exeprefix ./stockfish $args $postfix"
@@ -92,6 +110,7 @@ cat << EOF > game.exp
  send "uci\n"
  expect "uciok"
 
+ # send "setoption name Debug Log File value debug.log\n"
  send "setoption name Threads value $threads\n"
 
  send "ucinewgame\n"
@@ -107,10 +126,32 @@ cat << EOF > game.exp
  send "go depth 10\n"
  expect "bestmove"
 
+ send "setoption name UCI_ShowWDL value true\n"
+ send "position startpos\n"
+ send "flip\n"
+ send "go depth 5\n"
+ expect "bestmove"
+
+ send "setoption name Skill Level value 10\n"
+ send "position startpos\n"
+ send "go depth 5\n"
+ expect "bestmove"
+
+ send "setoption name Clear Hash\n"
+
+ send "setoption name EvalFile value verify.nnue\n"
+ send "position startpos\n"
+ send "go depth 5\n"
+ expect "bestmove"
+
+ send "setoption name MultiPV value 4\n"
+ send "position startpos\n"
+ send "go depth 5\n"
+
  send "quit\n"
  expect eof
 
- # return error code of the spawned program, useful for valgrind
+ # return error code of the spawned program, useful for Valgrind
  lassign [wait] pid spawnid os_error_flag value
  exit \$value
 EOF
@@ -128,10 +169,17 @@ cat << EOF > syzygy.exp
  send "setoption name SyzygyPath value ../tests/syzygy/\n"
  expect "info string Found 35 tablebases" {} timeout {exit 1}
  send "bench 128 1 8 default depth\n"
+ send "ucinewgame\n"
+ send "position fen 4k3/PP6/8/8/8/8/8/4K3 w - - 0 1\n"
+ send "go depth 5\n"
+ expect "bestmove"
+ send "position fen 8/1P6/2B5/8/4K3/8/6k1/8 w - - 0 1\n"
+ send "go depth 5\n"
+ expect "bestmove"
  send "quit\n"
  expect eof
 
- # return error code of the spawned program, useful for valgrind
+ # return error code of the spawned program, useful for Valgrind
  lassign [wait] pid spawnid os_error_flag value
  exit \$value
 EOF
@@ -146,6 +194,6 @@ do
 
 done
 
-rm -f tsan.supp
+rm -f tsan.supp bench_tmp.epd
 
 echo "instrumented testing OK"

tests/signature.sh

@@ -11,7 +11,7 @@ trap 'error ${LINENO}' ERR
 
 # obtain
 
-signature=`./stockfish bench 2>&1 | grep "Nodes searched  : " | awk '{print $4}'`
+signature=`eval "$WINE_PATH ./stockfish bench 2>&1" | grep "Nodes searched  : " | awk '{print $4}'`
 
 if [ $# -gt 0 ]; then
    # compare to given reference