Stockfish 5

Stockfish bench signature is: 8732553

Readme.md

@@ -1,5 +1,4 @@
-1. Introduction
----------------
+### Overview
 
 Stockfish is a free UCI chess engine derived from Glaurung 2.1. It is
 not a complete chess program and requires some UCI-compatible GUI
@@ -8,46 +7,37 @@ Partner or Fritz) in order to be used comfortably. Read the
 documentation for your GUI of choice for information about how to use
 Stockfish with it.
 
-This version of Stockfish supports up to 32 CPUs, but has not been
-tested thoroughly with more than 4.  The program tries to detect the
-number of CPUs on your computer and sets the number of search threads
-accordingly, but please be aware that the detection is not always
-correct. It is therefore recommended to inspect the value of the
-"Threads" UCI parameter, and to make sure it equals the number of CPU
-cores on your computer. If you are using more than eight threads, it is
-recommended to raise the value of the "Min Split Depth" UCI parameter to
-7.
+This version of Stockfish supports up to 128 CPUs. The engine defaults
+to one search thread, so it is therefore recommended to inspect the value of
+the *Threads* UCI parameter, and to make sure it equals the number of CPU
+cores on your computer.
 
 
-2. Files
---------
+### Files
 
 This distribution of Stockfish consists of the following files:
 
-  * Readme.txt, the file you are currently reading.
+  * Readme.md, the file you are currently reading.
 
   * Copying.txt, a text file containing the GNU General Public License.
 
-  * src/, a subdirectory containing the full source code, including a
-    Makefile that can be used to compile Stockfish on Unix-like systems.
-    For further information about how to compile Stockfish yourself read
-    section 4 below.
+  * src, a subdirectory containing the full source code, including a Makefile
+    that can be used to compile Stockfish on Unix-like systems. For further
+    information about how to compile Stockfish yourself read section below.
 
   * polyglot.ini, for using Stockfish with Fabien Letouzey's PolyGlot
     adapter.
 
 
-3. Opening books
-----------------
+### Opening books
 
 This version of Stockfish has support for PolyGlot opening books. For
 information about how to create such books, consult the PolyGlot
-documentation. The book file can be selected by setting the "Book File"
+documentation. The book file can be selected by setting the *Book File*
 UCI parameter.
 
 
-4. Compiling it yourself
-------------------------
+### Compiling it yourself
 
 On Unix-like systems, it should be possible to compile Stockfish
 directly from the source code with the included Makefile.
@@ -55,17 +45,16 @@ directly from the source code with the included Makefile.
 Stockfish has support for 32 or 64-bit CPUs, the hardware POPCNT
 instruction, big-endian machines such as Power PC, and other platforms.
 
-In general it is recommended to run 'make help' to see a list of make
-targets with corresponding descriptions. When not using Makefile to
+In general it is recommended to run `make help` to see a list of make
+targets with corresponding descriptions. When not using the Makefile to
 compile (for instance with Microsoft MSVC) you need to manually
-set/unset some switches in the compiler command line; see file "types.h"
+set/unset some switches in the compiler command line; see file *types.h*
 for a quick reference.
 
 
-5. Terms of use
----------------
+### Terms of use
 
-Stockfish is free, and distributed under the GNU General Public License
+Stockfish is free, and distributed under the **GNU General Public License**
 (GPL). Essentially, this means that you are free to do almost exactly
 what you want with the program, including distributing it among your
 friends, making it available for download from your web site, selling
@@ -78,4 +67,4 @@ to where the source code can be found. If you make any changes to the
 source code, these changes must also be made available under the GPL.
 
 For full details, read the copy of the GPL found in the file named
-Copying.txt.
+*Copying.txt*

polyglot.ini

@@ -1,4 +1,3 @@
-
 [PolyGlot]
 
 EngineDir = .
@@ -15,21 +14,22 @@ ResignScore = 600
 
 [Engine]
 
-Use Search Log = false
+Write Debug Log = false
+Write Search Log = false
 Search Log Filename = SearchLog.txt
 Book File = book.bin
 Best Book Move = false
-Mobility (Middle Game) = 100
+Contempt Factor = 0
+Mobility (Midgame) = 100
 Mobility (Endgame) = 100
-Passed Pawns (Middle Game) = 100
+Pawn Structure (Midgame) = 100
+Pawn Structure (Endgame) = 100
+Passed Pawns (Midgame) = 100
 Passed Pawns (Endgame) = 100
 Space = 100
-Aggressiveness = 100
-Cowardice = 100
-Min Split Depth = 4
-Max Threads per Split Point = 5
+King Safety = 100
+Min Split Depth = 0
 Threads = 1
-Use Sleeping Threads = false
 Hash = 128
 Ponder = true
 OwnBook = false
@@ -39,5 +39,5 @@ Emergency Move Horizon = 40
 Emergency Base Time = 200
 Emergency Move Time = 70
 Minimum Thinking Time = 20
+Slow Mover = 100
 UCI_Chess960 = false
-UCI_AnalyseMode = false

src/Makefile

@@ -1,6 +1,6 @@
 # Stockfish, a UCI chess playing engine derived from Glaurung 2.1
 # Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-# Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+# Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 #
 # Stockfish is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -35,7 +35,7 @@ endif
 BINDIR = $(PREFIX)/bin
 
 ### Built-in benchmark for pgo-builds
-PGOBENCH = ./$(EXE) bench 32 1 10 default depth
+PGOBENCH = ./$(EXE) bench 32 1 1 default time
 
 ### Object files
 OBJS = benchmark.o bitbase.o bitboard.o book.o endgame.o evaluate.o main.o \
@@ -58,108 +58,85 @@ OBJS = benchmark.o bitbase.o bitboard.o book.o endgame.o evaluate.o main.o \
 # bsfq = yes/no       --- -DUSE_BSFQ       --- Use bsfq x86_64 asm-instruction (only
 #                                              with GCC and ICC 64-bit)
 # popcnt = yes/no     --- -DUSE_POPCNT     --- Use popcnt x86_64 asm-instruction
+# sse = yes/no        --- -msse            --- Use Intel Streaming SIMD Extensions
+# pext = yes/no       --- -DUSE_PEXT       --- Use pext x86_64 asm-instruction
 #
 # Note that Makefile is space sensitive, so when adding new architectures
 # or modifying existing flags, you have to make sure there are no extra spaces
 # at the end of the line for flag values.
 
-### 2.1. General
-debug = no
+### 2.1. General and architecture defaults
 optimize = yes
+debug = no
+os = any
+bits = 32
+prefetch = no
+bsfq = no
+popcnt = no
+sse = no
+pext = no
 
 ### 2.2 Architecture specific
 
-# General-section
-ifeq ($(ARCH),general-64)
-	arch = any
-	os = any
-	bits = 64
-	prefetch = no
-	bsfq = no
-	popcnt = no
-endif
-
 ifeq ($(ARCH),general-32)
 	arch = any
-	os = any
-	bits = 32
-	prefetch = no
-	bsfq = no
-	popcnt = no
-endif
-
-# x86-section
-ifeq ($(ARCH),x86-64)
-	arch = x86_64
-	os = any
-	bits = 64
-	prefetch = yes
-	bsfq = yes
-	popcnt = no
-endif
-
-ifeq ($(ARCH),x86-64-modern)
-	arch = x86_64
-	os = any
-	bits = 64
-	prefetch = yes
-	bsfq = yes
-	popcnt = yes
-endif
-
-ifeq ($(ARCH),x86-32)
-	arch = i386
-	os = any
-	bits = 32
-	prefetch = yes
-	bsfq = no
-	popcnt = no
 endif
 
 ifeq ($(ARCH),x86-32-old)
 	arch = i386
-	os = any
-	bits = 32
-	prefetch = no
-	bsfq = no
-	popcnt = no
 endif
 
-# osx-section
-ifeq ($(ARCH),osx-ppc-64)
-	arch = ppc64
-	os = osx
+ifeq ($(ARCH),x86-32)
+	arch = i386
+	prefetch = yes
+	sse = yes
+endif
+
+ifeq ($(ARCH),general-64)
+	arch = any
 	bits = 64
-	prefetch = no
-	bsfq = no
-	popcnt = no
 endif
 
-ifeq ($(ARCH),osx-ppc-32)
-	arch = ppc
-	os = osx
-	bits = 32
-	prefetch = no
-	bsfq = no
-	popcnt = no
-endif
-
-ifeq ($(ARCH),osx-x86-64)
+ifeq ($(ARCH),x86-64)
 	arch = x86_64
-	os = osx
 	bits = 64
 	prefetch = yes
 	bsfq = yes
-	popcnt = no
+	sse = yes
 endif
 
-ifeq ($(ARCH),osx-x86-32)
-	arch = i386
-	os = osx
-	bits = 32
+ifeq ($(ARCH),x86-64-modern)
+	arch = x86_64
+	bits = 64
 	prefetch = yes
-	bsfq = no
-	popcnt = no
+	bsfq = yes
+	popcnt = yes
+	sse = yes
+endif
+
+ifeq ($(ARCH),x86-64-bmi2)
+	arch = x86_64
+	bits = 64
+	prefetch = yes
+	bsfq = yes
+	popcnt = yes
+	sse = yes
+	pext = yes
+endif
+
+ifeq ($(ARCH),armv7)
+	arch = armv7
+	prefetch = yes
+	bsfq = yes
+endif
+
+ifeq ($(ARCH),ppc-32)
+	arch = ppc
+endif
+
+ifeq ($(ARCH),ppc-64)
+	arch = ppc64
+	bits = 64
 endif
 
 
@@ -168,87 +145,72 @@ endif
 ### ==========================================================================
 
 ### 3.1 Selecting compiler (default = gcc)
+
+CXXFLAGS += -Wall -Wcast-qual -fno-exceptions -fno-rtti $(EXTRACXXFLAGS)
+LDFLAGS += $(EXTRALDFLAGS)
+
 ifeq ($(COMP),)
 	COMP=gcc
 endif
 
-ifeq ($(COMP),mingw)
-	comp=mingw
-	CXX=g++
-	profile_prepare = gcc-profile-prepare
-	profile_make = gcc-profile-make
-	profile_use = gcc-profile-use
-	profile_clean = gcc-profile-clean
-endif
-
 ifeq ($(COMP),gcc)
 	comp=gcc
 	CXX=g++
-	profile_prepare = gcc-profile-prepare
-	profile_make = gcc-profile-make
-	profile_use = gcc-profile-use
-	profile_clean = gcc-profile-clean
+	CXXFLAGS += -ansi -pedantic -Wno-long-long -Wextra -Wshadow
+endif
+
+ifeq ($(COMP),mingw)
+	comp=mingw
+	CXX=g++
+	CXXFLAGS += -Wextra -Wshadow
+	LDFLAGS += -static-libstdc++ -static-libgcc
 endif
 
 ifeq ($(COMP),icc)
 	comp=icc
 	CXX=icpc
-	profile_prepare = icc-profile-prepare
-	profile_make = icc-profile-make
-	profile_use = icc-profile-use
-	profile_clean = icc-profile-clean
+	CXXFLAGS += -diag-disable 1476,10120 -Wcheck -Wabi -Wdeprecated -strict-ansi
 endif
 
 ifeq ($(COMP),clang)
 	comp=clang
 	CXX=clang++
+	CXXFLAGS += -ansi -pedantic -Wno-long-long -Wextra -Wshadow
+endif
+
+ifeq ($(comp),icc)
+	profile_prepare = icc-profile-prepare
+	profile_make = icc-profile-make
+	profile_use = icc-profile-use
+	profile_clean = icc-profile-clean
+else
 	profile_prepare = gcc-profile-prepare
 	profile_make = gcc-profile-make
 	profile_use = gcc-profile-use
 	profile_clean = gcc-profile-clean
 endif
 
-### 3.2 General compiler settings
-CXXFLAGS = -g -Wall -Wcast-qual -fno-exceptions -fno-rtti $(EXTRACXXFLAGS)
-
-ifeq ($(comp),gcc)
-	CXXFLAGS += -ansi -pedantic -Wno-long-long -Wextra -Wshadow
+ifeq ($(UNAME),Darwin)
+	CXXFLAGS += -arch $(arch) -mmacosx-version-min=10.6
+	LDFLAGS += -arch $(arch) -mmacosx-version-min=10.6
 endif
 
-ifeq ($(comp),mingw)
-	CXXFLAGS += -Wextra -Wshadow
-endif
-
-ifeq ($(comp),icc)
-	CXXFLAGS += -wd383,981,1418,1419,10187,10188,11505,11503 -Wcheck -Wabi -Wdeprecated -strict-ansi
-endif
-
-ifeq ($(comp),clang)
-	CXXFLAGS += -ansi -pedantic -Wno-long-long -Wextra -Wshadow
-endif
-
-ifeq ($(os),osx)
-	CXXFLAGS += -arch $(arch)
-endif
-
-### 3.3 General linker settings
-LDFLAGS = $(EXTRALDFLAGS)
-
 ### On mingw use Windows threads, otherwise POSIX
 ifneq ($(comp),mingw)
-	# Haiku has pthreads in its libroot, so only link it in on other platforms
-	ifneq ($(UNAME),Haiku)
-		LDFLAGS += -lpthread
+	# On Android Bionic's C library comes with its own pthread implementation bundled in
+	ifneq ($(arch),armv7)
+		# Haiku has pthreads in its libroot, so only link it in on other platforms
+		ifneq ($(UNAME),Haiku)
+			LDFLAGS += -lpthread
+		endif
 	endif
 endif
 
-ifeq ($(os),osx)
-	LDFLAGS += -arch $(arch)
-endif
-
 ### 3.4 Debugging
 ifeq ($(debug),no)
 	CXXFLAGS += -DNDEBUG
+else
+	CXXFLAGS += -g
 endif
 
 ### 3.5 Optimization
@@ -257,7 +219,7 @@ ifeq ($(optimize),yes)
 	ifeq ($(comp),gcc)
 		CXXFLAGS += -O3
 
-		ifeq ($(os),osx)
+		ifeq ($(UNAME),Darwin)
 			ifeq ($(arch),i386)
 				CXXFLAGS += -mdynamic-no-pic
 			endif
@@ -265,6 +227,10 @@ ifeq ($(optimize),yes)
 				CXXFLAGS += -mdynamic-no-pic
 			endif
 		endif
+
+		ifeq ($(arch),armv7)
+			CXXFLAGS += -fno-gcse -mthumb -march=armv7-a -mfloat-abi=softfp
+		endif
 	endif
 
 	ifeq ($(comp),mingw)
@@ -272,18 +238,21 @@ ifeq ($(optimize),yes)
 	endif
 
 	ifeq ($(comp),icc)
-		ifeq ($(os),osx)
+		ifeq ($(UNAME),Darwin)
 			CXXFLAGS += -fast -mdynamic-no-pic
 		else
-			CXXFLAGS += -O3
+			CXXFLAGS += -fast
 		endif
 	endif
 
 	ifeq ($(comp),clang)
-		### -O4 requires a linker that supports LLVM's LTO
 		CXXFLAGS += -O3
 
-		ifeq ($(os),osx)
+		ifeq ($(UNAME),Darwin)
+			ifeq ($(pext),no)
+				CXXFLAGS += -flto
+				LDFLAGS += $(CXXFLAGS)
+			endif
 			ifeq ($(arch),i386)
 				CXXFLAGS += -mdynamic-no-pic
 			endif
@@ -301,8 +270,10 @@ endif
 
 ### 3.7 prefetch
 ifeq ($(prefetch),yes)
-	CXXFLAGS += -msse
-	DEPENDFLAGS += -msse
+	ifeq ($(sse),yes)
+		CXXFLAGS += -msse
+		DEPENDFLAGS += -msse
+	endif
 else
 	CXXFLAGS += -DNO_PREFETCH
 endif
@@ -317,11 +288,20 @@ ifeq ($(popcnt),yes)
 	CXXFLAGS += -msse3 -DUSE_POPCNT
 endif
 
-### 3.10 Link Time Optimization, it works since gcc 4.5 but not on mingw.
+### 3.10 pext
+ifeq ($(pext),yes)
+	CXXFLAGS += -DUSE_PEXT
+	ifeq ($(comp),$(filter $(comp),gcc clang mingw))
+		CXXFLAGS += -mbmi -mbmi2
+	endif
+endif
+
+### 3.11 Link Time Optimization, it works since gcc 4.5 but not on mingw.
 ### This is a mix of compile and link time options because the lto link phase
 ### needs access to the optimization flags.
 ifeq ($(comp),gcc)
 	ifeq ($(optimize),yes)
+	ifeq ($(debug),no)
 		GCC_MAJOR := `$(CXX) -dumpversion | cut -f1 -d.`
 		GCC_MINOR := `$(CXX) -dumpversion | cut -f2 -d.`
 		ifeq (1,$(shell expr \( $(GCC_MAJOR) \> 4 \) \| \( $(GCC_MAJOR) \= 4 \& $(GCC_MINOR) \>= 5 \)))
@@ -329,6 +309,7 @@ ifeq ($(comp),gcc)
 			LDFLAGS += $(CXXFLAGS)
 		endif
 	endif
+	endif
 endif
 
 ### ==========================================================================
@@ -343,43 +324,43 @@ help:
 	@echo ""
 	@echo "Supported targets:"
 	@echo ""
-	@echo "build                > Build unoptimized version"
-	@echo "profile-build        > Build PGO-optimized version"
-	@echo "strip                > Strip executable"
-	@echo "install              > Install executable"
-	@echo "clean                > Clean up"
-	@echo "testrun              > Make sample run"
+	@echo "build                   > Standard build"
+	@echo "profile-build           > PGO build"
+	@echo "strip                   > Strip executable"
+	@echo "install                 > Install executable"
+	@echo "clean                   > Clean up"
 	@echo ""
 	@echo "Supported archs:"
 	@echo ""
-	@echo "x86-64               > x86 64-bit"
-	@echo "x86-64-modern        > x86 64-bit with runtime support for popcnt instruction"
-	@echo "x86-32               > x86 32-bit excluding old hardware without SSE-support"
-	@echo "x86-32-old           > x86 32-bit including also very old hardware"
-	@echo "osx-ppc-64           > PPC-Mac OS X 64 bit"
-	@echo "osx-ppc-32           > PPC-Mac OS X 32 bit"
-	@echo "osx-x86-64           > x86-Mac OS X 64 bit"
-	@echo "osx-x86-32           > x86-Mac OS X 32 bit"
-	@echo "general-64           > unspecified 64-bit"
-	@echo "general-32           > unspecified 32-bit"
+	@echo "x86-64                  > x86 64-bit"
+	@echo "x86-64-modern           > x86 64-bit with popcnt support"
+	@echo "x86-64-bmi2             > x86 64-bit with pext support"
+	@echo "x86-32                  > x86 32-bit with SSE support"
+	@echo "x86-32-old              > x86 32-bit fall back for old hardware"
+	@echo "ppc-64                  > PPC 64-bit"
+	@echo "ppc-32                  > PPC 32-bit"
+	@echo "armv7                   > ARMv7 32-bit"
+	@echo "general-64              > unspecified 64-bit"
+	@echo "general-32              > unspecified 32-bit"
 	@echo ""
-	@echo "Supported comps:"
+	@echo "Supported compilers:"
 	@echo ""
-	@echo "gcc                  > Gnu compiler (default)"
-	@echo "icc                  > Intel compiler"
-	@echo "mingw                > Gnu compiler with MinGW under Windows"
-	@echo "clang                > LLVM Clang compiler"
+	@echo "gcc                     > Gnu compiler (default)"
+	@echo "mingw                   > Gnu compiler with MinGW under Windows"
+	@echo "clang                   > LLVM Clang compiler"
+	@echo "icc                     > Intel compiler"
 	@echo ""
 	@echo "Non-standard targets:"
 	@echo ""
-	@echo "make hpux           >  Compile for HP-UX. Compiler = aCC"
+	@echo "make hpux               >  Compile for HP-UX. Compiler = aCC"
 	@echo ""
 	@echo "Examples. If you don't know what to do, you likely want to run: "
 	@echo ""
-	@echo "make profile-build ARCH=x86-64    (This is for 64-bit systems)"
-	@echo "make profile-build ARCH=x86-32    (This is for 32-bit systems)"
+	@echo "make build ARCH=x86-64    (This is for 64-bit systems)"
+	@echo "make build ARCH=x86-32    (This is for 32-bit systems)"
 	@echo ""
 
+.PHONY: build profile-build
 build:
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) config-sanity
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) all
@@ -415,9 +396,6 @@ install:
 clean:
 	$(RM) $(EXE) $(EXE).exe *.o .depend *~ core bench.txt *.gcda
 
-testrun:
-	@$(PGOBENCH)
-
 default:
 	help
 
@@ -438,6 +416,8 @@ config-sanity:
 	@echo "prefetch: '$(prefetch)'"
 	@echo "bsfq: '$(bsfq)'"
 	@echo "popcnt: '$(popcnt)'"
+	@echo "sse: '$(sse)'"
+	@echo "pext: '$(pext)'"
 	@echo ""
 	@echo "Flags:"
 	@echo "CXX: $(CXX)"
@@ -449,12 +429,14 @@ config-sanity:
 	@test "$(debug)" = "yes" || test "$(debug)" = "no"
 	@test "$(optimize)" = "yes" || test "$(optimize)" = "no"
 	@test "$(arch)" = "any" || test "$(arch)" = "x86_64" || test "$(arch)" = "i386" || \
-	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc"
-	@test "$(os)" = "any" || test "$(os)" = "osx"
+	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc" || test "$(arch)" = "armv7"
+	@test "$(os)" = "any"
 	@test "$(bits)" = "32" || test "$(bits)" = "64"
 	@test "$(prefetch)" = "yes" || test "$(prefetch)" = "no"
 	@test "$(bsfq)" = "yes" || test "$(bsfq)" = "no"
 	@test "$(popcnt)" = "yes" || test "$(popcnt)" = "no"
+	@test "$(sse)" = "yes" || test "$(sse)" = "no"
+	@test "$(pext)" = "yes" || test "$(pext)" = "no"
 	@test "$(comp)" = "gcc" || test "$(comp)" = "icc" || test "$(comp)" = "mingw" || test "$(comp)" = "clang"
 
 $(EXE): $(OBJS)

src/benchmark.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,6 +23,7 @@
 #include <vector>
 
 #include "misc.h"
+#include "notation.h"
 #include "position.h"
 #include "search.h"
 #include "thread.h"
@@ -47,15 +48,29 @@ static const char* Defaults[] = {
   "3r1rk1/p5pp/bpp1pp2/8/q1PP1P2/b3P3/P2NQRPP/1R2B1K1 b - - 6 22",
   "r1q2rk1/2p1bppp/2Pp4/p6b/Q1PNp3/4B3/PP1R1PPP/2K4R w - - 2 18",
   "4k2r/1pb2ppp/1p2p3/1R1p4/3P4/2r1PN2/P4PPP/1R4K1 b - - 3 22",
-  "3q2k1/pb3p1p/4pbp1/2r5/PpN2N2/1P2P2P/5PP1/Q2R2K1 b - - 4 26"
+  "3q2k1/pb3p1p/4pbp1/2r5/PpN2N2/1P2P2P/5PP1/Q2R2K1 b - - 4 26",
+  "6k1/6p1/6Pp/ppp5/3pn2P/1P3K2/1PP2P2/3N4 b - - 0 1",
+  "3b4/5kp1/1p1p1p1p/pP1PpP1P/P1P1P3/3KN3/8/8 w - - 0 1",
+  "2K5/p7/7P/5pR1/8/5k2/r7/8 w - - 0 1",
+  "8/6pk/1p6/8/PP3p1p/5P2/4KP1q/3Q4 w - - 0 1",
+  "7k/3p2pp/4q3/8/4Q3/5Kp1/P6b/8 w - - 0 1",
+  "8/2p5/8/2kPKp1p/2p4P/2P5/3P4/8 w - - 0 1",
+  "8/1p3pp1/7p/5P1P/2k3P1/8/2K2P2/8 w - - 0 1",
+  "8/pp2r1k1/2p1p3/3pP2p/1P1P1P1P/P5KR/8/8 w - - 0 1",
+  "8/3p4/p1bk3p/Pp6/1Kp1PpPp/2P2P1P/2P5/5B2 b - - 0 1",
+  "5k2/7R/4P2p/5K2/p1r2P1p/8/8/8 b - - 0 1",
+  "6k1/6p1/P6p/r1N5/5p2/7P/1b3PP1/4R1K1 w - - 0 1",
+  "1r3k2/4q3/2Pp3b/3Bp3/2Q2p2/1p1P2P1/1P2KP2/3N4 w - - 0 1",
+  "6k1/4pp1p/3p2p1/P1pPb3/R7/1r2P1PP/3B1P2/6K1 w - - 0 1",
+  "8/3p3B/5p2/5P2/p7/PP5b/k7/6K1 w - - 0 1"
 };
 
 
 /// benchmark() runs a simple benchmark by letting Stockfish analyze a set
-/// of positions for a given limit each. There are five parameters; the
+/// of positions for a given limit each. There are five parameters: the
 /// transposition table size, the number of search threads that should
 /// be used, the limit value spent for each position (optional, default is
-/// depth 12), an optional file name where to look for positions in fen
+/// depth 13), an optional file name where to look for positions in FEN
 /// format (defaults are the positions defined above) and the type of the
 /// limit value: depth (default), time in secs or number of nodes.
 
@@ -66,9 +81,9 @@ void benchmark(const Position& current, istream& is) {
   vector<string> fens;
 
   // Assign default values to missing arguments
-  string ttSize    = (is >> token) ? token : "128";
+  string ttSize    = (is >> token) ? token : "32";
   string threads   = (is >> token) ? token : "1";
-  string limit     = (is >> token) ? token : "12";
+  string limit     = (is >> token) ? token : "13";
   string fenFile   = (is >> token) ? token : "default";
   string limitType = (is >> token) ? token : "depth";
 
@@ -82,14 +97,17 @@ void benchmark(const Position& current, istream& is) {
   else if (limitType == "nodes")
       limits.nodes = atoi(limit.c_str());
 
+  else if (limitType == "mate")
+      limits.mate = atoi(limit.c_str());
+
   else
       limits.depth = atoi(limit.c_str());
 
   if (fenFile == "default")
-      fens.assign(Defaults, Defaults + 16);
+      fens.assign(Defaults, Defaults + 30);
 
   else if (fenFile == "current")
-      fens.push_back(current.to_fen());
+      fens.push_back(current.fen());
 
   else
   {
@@ -99,7 +117,7 @@ void benchmark(const Position& current, istream& is) {
       if (!file.is_open())
       {
           cerr << "Unable to open file " << fenFile << endl;
-          exit(EXIT_FAILURE);
+          return;
       }
 
       while (getline(file, fen))
@@ -109,31 +127,43 @@ void benchmark(const Position& current, istream& is) {
       file.close();
   }
 
-  int64_t nodes = 0;
+  uint64_t nodes = 0;
   Search::StateStackPtr st;
   Time::point elapsed = Time::now();
 
-  for (size_t i = 0; i < fens.size(); i++)
+  for (size_t i = 0; i < fens.size(); ++i)
   {
-      Position pos(fens[i], Options["UCI_Chess960"], Threads.main_thread());
+      Position pos(fens[i], Options["UCI_Chess960"], Threads.main());
 
       cerr << "\nPosition: " << i + 1 << '/' << fens.size() << endl;
 
-      if (limitType == "perft")
+      if (limitType == "divide")
+          for (MoveList<LEGAL> it(pos); *it; ++it)
+          {
+              StateInfo si;
+              pos.do_move(*it, si);
+              uint64_t cnt = limits.depth > 1 ? Search::perft(pos, (limits.depth - 1) * ONE_PLY) : 1;
+              pos.undo_move(*it);
+              cerr << move_to_uci(*it, pos.is_chess960()) << ": " << cnt << endl;
+              nodes += cnt;
+          }
+      else if (limitType == "perft")
       {
-          size_t cnt = Search::perft(pos, limits.depth * ONE_PLY);
+          uint64_t cnt = Search::perft(pos, limits.depth * ONE_PLY);
           cerr << "\nPerft " << limits.depth  << " leaf nodes: " << cnt << endl;
           nodes += cnt;
       }
       else
       {
-          Threads.start_searching(pos, limits, vector<Move>(), st);
-          Threads.wait_for_search_finished();
-          nodes += Search::RootPosition.nodes_searched();
+          Threads.start_thinking(pos, limits, st);
+          Threads.wait_for_think_finished();
+          nodes += Search::RootPos.nodes_searched();
       }
   }
 
-  elapsed = Time::now() - elapsed + 1; // Assure positive to avoid a 'divide by zero'
+  elapsed = Time::now() - elapsed + 1; // Ensure positivity to avoid a 'divide by zero'
+
+  dbg_print(); // Just before to exit
 
   cerr << "\n==========================="
        << "\nTotal time (ms) : " << elapsed

src/bitbase.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,12 +18,32 @@
 */
 
 #include <cassert>
+#include <vector>
 
 #include "bitboard.h"
 #include "types.h"
 
 namespace {
 
+  // There are 24 possible pawn squares: the first 4 files and ranks from 2 to 7
+  const unsigned MAX_INDEX = 2*24*64*64; // stm * psq * wksq * bksq = 196608
+
+  // Each uint32_t stores results of 32 positions, one per bit
+  uint32_t KPKBitbase[MAX_INDEX / 32];
+
+  // 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 us, Square bksq, Square wksq, Square psq) {
+    return wksq + (bksq << 6) + (us << 12) + (file_of(psq) << 13) + ((RANK_7 - rank_of(psq)) << 15);
+  }
+
   enum Result {
     INVALID = 0,
     UNKNOWN = 1,
@@ -35,196 +55,121 @@ namespace {
 
   struct KPKPosition {
 
-    Result classify_leaf(int idx);
-    Result classify(int idx, Result db[]);
+    KPKPosition(unsigned idx);
+    operator Result() const { return result; }
+    Result classify(const std::vector<KPKPosition>& db)
+    { return us == WHITE ? classify<WHITE>(db) : classify<BLACK>(db); }
 
   private:
-    template<Color Us> Result classify(const Result db[]) const;
+    template<Color Us> Result classify(const std::vector<KPKPosition>& db);
 
-    template<Color Us> Bitboard k_attacks() const {
-      return Us == WHITE ? StepAttacksBB[W_KING][wksq] : StepAttacksBB[B_KING][bksq];
-    }
-
-    Bitboard p_attacks() const { return StepAttacksBB[W_PAWN][psq]; }
-    void decode_index(int idx);
-
-    Square wksq, bksq, psq;
-    Color stm;
+    Color us;
+    Square bksq, wksq, psq;
+    Result result;
   };
 
-  // The possible pawns squares are 24, the first 4 files and ranks from 2 to 7
-  const int IndexMax = 2 * 24 * 64 * 64; // stm * wp_sq * wk_sq * bk_sq = 196608
-
-  // Each uint32_t stores results of 32 positions, one per bit
-  uint32_t KPKBitbase[IndexMax / 32];
-
-  int index(Square wksq, Square bksq, Square psq, Color stm);
-}
+} // namespace
 
 
-uint32_t Bitbases::probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm) {
+bool Bitbases::probe_kpk(Square wksq, Square wpsq, Square bksq, Color us) {
 
-  int idx = index(wksq, bksq, wpsq, stm);
-  return KPKBitbase[idx / 32] & (1 << (idx & 31));
+  assert(file_of(wpsq) <= FILE_D);
+
+  unsigned idx = index(us, bksq, wksq, wpsq);
+  return KPKBitbase[idx / 32] & (1 << (idx & 0x1F));
 }
 
 
 void Bitbases::init_kpk() {
 
-  Result db[IndexMax];
-  KPKPosition pos;
-  int idx, bit, repeat = 1;
+  unsigned idx, repeat = 1;
+  std::vector<KPKPosition> db;
+  db.reserve(MAX_INDEX);
 
-  // Initialize table with known win / draw positions
-  for (idx = 0; idx < IndexMax; idx++)
-      db[idx] = pos.classify_leaf(idx);
+  // Initialize db with known win / draw positions
+  for (idx = 0; idx < MAX_INDEX; ++idx)
+      db.push_back(KPKPosition(idx));
 
-  // Iterate until all positions are classified (30 cycles needed)
+  // 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 < IndexMax; idx++)
-          if (db[idx] == UNKNOWN && (db[idx] = pos.classify(idx, db)) != UNKNOWN)
-              repeat = 1;
+      for (repeat = idx = 0; idx < MAX_INDEX; ++idx)
+          repeat |= (db[idx] == UNKNOWN && db[idx].classify(db) != UNKNOWN);
 
-  // Map 32 position results into one KPKBitbase[] entry
-  for (idx = 0; idx < IndexMax / 32; idx++)
-      for (bit = 0; bit < 32; bit++)
-          if (db[32 * idx + bit] == WIN)
-              KPKBitbase[idx] |= 1 << bit;
+  // Map 32 results into one KPKBitbase[] entry
+  for (idx = 0; idx < MAX_INDEX; ++idx)
+      if (db[idx] == WIN)
+          KPKBitbase[idx / 32] |= 1 << (idx & 0x1F);
 }
 
 
 namespace {
 
-  // A KPK bitbase index is an integer in [0, IndexMax] range
-  //
-  // Information is mapped in this way
-  //
-  // bit     0: side to move (WHITE or BLACK)
-  // bit  1- 6: black king square (from SQ_A1 to SQ_H8)
-  // bit  7-12: white king square (from SQ_A1 to SQ_H8)
-  // bit 13-14: white pawn file (from FILE_A to FILE_D)
-  // bit 15-17: white pawn rank - 1 (from RANK_2 - 1 to RANK_7 - 1)
+  KPKPosition::KPKPosition(unsigned idx) {
 
-  int index(Square w, Square b, Square p, Color c) {
-
-    assert(file_of(p) <= FILE_D);
-
-    return c + (b << 1) + (w << 7) + (file_of(p) << 13) + ((rank_of(p) - 1) << 15);
-  }
-
-  void KPKPosition::decode_index(int idx) {
-
-    stm  = Color(idx & 1);
-    bksq = Square((idx >> 1) & 63);
-    wksq = Square((idx >> 7) & 63);
-    psq  = File((idx >> 13) & 3) | Rank((idx >> 15) + 1);
-  }
-
-  Result KPKPosition::classify_leaf(int idx) {
-
-    decode_index(idx);
+    wksq = Square((idx >>  0) & 0x3F);
+    bksq = Square((idx >>  6) & 0x3F);
+    us   = Color ((idx >> 12) & 0x01);
+    psq  = make_square(File((idx >> 13) & 0x03), Rank(RANK_7 - (idx >> 15)));
+    result  = UNKNOWN;
 
     // Check if two pieces are on the same square or if a king can be captured
-    if (   wksq == psq || wksq == bksq || bksq == psq
-        || (k_attacks<WHITE>() & bksq)
-        || (stm == WHITE && (p_attacks() & bksq)))
-        return INVALID;
+    if (   square_distance(wksq, bksq) <= 1
+        || wksq == psq
+        || bksq == psq
+        || (us == WHITE && (StepAttacksBB[PAWN][psq] & bksq)))
+        result = INVALID;
 
-    // The position is an immediate win if it is white to move and the white
-    // pawn can be promoted without getting captured.
-    if (   rank_of(psq) == RANK_7
-        && stm == WHITE
-        && wksq != psq + DELTA_N
-        && (   square_distance(bksq, psq + DELTA_N) > 1
-            ||(k_attacks<WHITE>() & (psq + DELTA_N))))
-        return WIN;
-
-    // Check for known draw positions
-    //
-    // Case 1: Stalemate
-    if (   stm == BLACK
-        && !(k_attacks<BLACK>() & ~(k_attacks<WHITE>() | p_attacks())))
-        return DRAW;
-
-    // Case 2: King can capture undefended pawn
-    if (   stm == BLACK
-        && (k_attacks<BLACK>() & psq & ~k_attacks<WHITE>()))
-        return DRAW;
-
-    // Case 3: Black king in front of white pawn
-    if (   bksq == psq + DELTA_N
-        && rank_of(psq) < RANK_7)
-        return DRAW;
-
-    // Case 4: White king in front of pawn and black has opposition
-    if (   stm == WHITE
-        && wksq == psq + DELTA_N
-        && bksq == wksq + DELTA_N + DELTA_N
-        && rank_of(psq) < RANK_5)
-        return DRAW;
-
-    // Case 5: Stalemate with rook pawn
-    if (   bksq == SQ_A8
-        && file_of(psq) == FILE_A)
-        return DRAW;
-
-    // Case 6: White king trapped on the rook file
-    if (   file_of(wksq) == FILE_A
-        && file_of(psq) == FILE_A
-        && rank_of(wksq) > rank_of(psq)
-        && bksq == wksq + 2)
-        return DRAW;
-
-    return UNKNOWN;
+    else if (us == WHITE)
+    {
+        // Immediate win if a pawn can be promoted without getting captured
+        if (   rank_of(psq) == RANK_7
+            && wksq != psq + DELTA_N
+            && (   square_distance(bksq, psq + DELTA_N) > 1
+                ||(StepAttacksBB[KING][wksq] & (psq + DELTA_N))))
+            result = WIN;
+    }
+    // Immediate draw if it is a stalemate or a king captures undefended pawn
+    else if (  !(StepAttacksBB[KING][bksq] & ~(StepAttacksBB[KING][wksq] | StepAttacksBB[PAWN][psq]))
+             || (StepAttacksBB[KING][bksq] & psq & ~StepAttacksBB[KING][wksq]))
+        result = DRAW;
   }
 
   template<Color Us>
-  Result KPKPosition::classify(const Result db[]) const {
+  Result KPKPosition::classify(const std::vector<KPKPosition>& db) {
 
-    // White to Move: If one move leads to a position classified as RESULT_WIN,
-    // the result of the current position is RESULT_WIN. If all moves lead to
-    // positions classified as RESULT_DRAW, the current position is classified
-    // RESULT_DRAW otherwise the current position is classified as RESULT_UNKNOWN.
+    // 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 RESULT_DRAW,
-    // the result of the current position is RESULT_DRAW. If all moves lead to
-    // positions classified as RESULT_WIN, the position is classified RESULT_WIN.
-    // Otherwise, the current position is classified as RESULT_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 Color Them = (Us == WHITE ? BLACK : WHITE);
 
     Result r = INVALID;
-    Bitboard b = k_attacks<Us>();
+    Bitboard b = StepAttacksBB[KING][Us == WHITE ? wksq : bksq];
 
     while (b)
-    {
-        r |= Us == WHITE ? db[index(pop_lsb(&b), bksq, psq, BLACK)]
-                         : db[index(wksq, pop_lsb(&b), psq, WHITE)];
-
-        if (Us == WHITE && (r & WIN))
-            return WIN;
-
-        if (Us == BLACK && (r & DRAW))
-            return DRAW;
-    }
+        r |= Us == WHITE ? db[index(Them, bksq, pop_lsb(&b), psq)]
+                         : db[index(Them, pop_lsb(&b), wksq, psq)];
 
     if (Us == WHITE && rank_of(psq) < RANK_7)
     {
         Square s = psq + DELTA_N;
-        r |= db[index(wksq, bksq, s, BLACK)]; // Single push
+        r |= db[index(BLACK, bksq, wksq, s)]; // Single push
 
-        if (rank_of(s) == RANK_3 && s != wksq && s != bksq)
-            r |= db[index(wksq, bksq, s + DELTA_N, BLACK)]; // Double push
-
-        if (r & WIN)
-            return WIN;
+        if (rank_of(psq) == RANK_2 && s != wksq && s != bksq)
+            r |= db[index(BLACK, bksq, wksq, s + DELTA_N)]; // Double push
     }
 
-    return r & UNKNOWN ? UNKNOWN : Us == WHITE ? DRAW : WIN;
+    if (Us == WHITE)
+        return result = r & WIN  ? WIN  : r & UNKNOWN ? UNKNOWN : DRAW;
+    else
+        return result = r & DRAW ? DRAW : r & UNKNOWN ? UNKNOWN : WIN;
   }
 
-  Result KPKPosition::classify(int idx, Result db[]) {
-
-    decode_index(idx);
-    return stm == WHITE ? classify<WHITE>(db) : classify<BLACK>(db);
-  }
-
-}
+} // namespace

src/bitboard.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,55 +18,52 @@
 */
 
 #include <algorithm>
-#include <cstring>
-#include <iostream>
+#include <cstring> // For memset
 
 #include "bitboard.h"
 #include "bitcount.h"
-#include "misc.h"
 #include "rkiss.h"
 
 CACHE_LINE_ALIGNMENT
 
-Bitboard RMasks[64];
-Bitboard RMagics[64];
-Bitboard* RAttacks[64];
-unsigned RShifts[64];
+Bitboard RMasks[SQUARE_NB];
+Bitboard RMagics[SQUARE_NB];
+Bitboard* RAttacks[SQUARE_NB];
+unsigned RShifts[SQUARE_NB];
 
-Bitboard BMasks[64];
-Bitboard BMagics[64];
-Bitboard* BAttacks[64];
-unsigned BShifts[64];
+Bitboard BMasks[SQUARE_NB];
+Bitboard BMagics[SQUARE_NB];
+Bitboard* BAttacks[SQUARE_NB];
+unsigned BShifts[SQUARE_NB];
 
-Bitboard SquareBB[64];
-Bitboard FileBB[8];
-Bitboard RankBB[8];
-Bitboard AdjacentFilesBB[8];
-Bitboard ThisAndAdjacentFilesBB[8];
-Bitboard InFrontBB[2][8];
-Bitboard StepAttacksBB[16][64];
-Bitboard BetweenBB[64][64];
-Bitboard DistanceRingsBB[64][8];
-Bitboard ForwardBB[2][64];
-Bitboard PassedPawnMask[2][64];
-Bitboard AttackSpanMask[2][64];
-Bitboard PseudoAttacks[6][64];
+Bitboard SquareBB[SQUARE_NB];
+Bitboard FileBB[FILE_NB];
+Bitboard RankBB[RANK_NB];
+Bitboard AdjacentFilesBB[FILE_NB];
+Bitboard InFrontBB[COLOR_NB][RANK_NB];
+Bitboard StepAttacksBB[PIECE_NB][SQUARE_NB];
+Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
+Bitboard LineBB[SQUARE_NB][SQUARE_NB];
+Bitboard DistanceRingsBB[SQUARE_NB][8];
+Bitboard ForwardBB[COLOR_NB][SQUARE_NB];
+Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB];
+Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB];
+Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 
-int SquareDistance[64][64];
+int SquareDistance[SQUARE_NB][SQUARE_NB];
 
 namespace {
 
   // De Bruijn sequences. See chessprogramming.wikispaces.com/BitScan
-  const uint64_t DeBruijn_64 = 0x218A392CD3D5DBFULL;
+  const uint64_t DeBruijn_64 = 0x3F79D71B4CB0A89ULL;
   const uint32_t DeBruijn_32 = 0x783A9B23;
 
   CACHE_LINE_ALIGNMENT
 
   int MS1BTable[256];
-  Square BSFTable[64];
+  Square BSFTable[SQUARE_NB];
   Bitboard RTable[0x19000]; // Storage space for rook attacks
   Bitboard BTable[0x1480];  // Storage space for bishop attacks
-  uint8_t BitCount8Bit[256];
 
   typedef unsigned (Fn)(Square, Bitboard);
 
@@ -75,19 +72,17 @@ namespace {
 
   FORCE_INLINE unsigned bsf_index(Bitboard b) {
 
-    if (Is64Bit)
-        return ((b & -b) * DeBruijn_64) >> 58;
-
-    // Use Matt Taylor's folding trick for 32 bit systems
+    // Matt Taylor's folding for 32 bit systems, extended to 64 bits by Kim Walisch
     b ^= (b - 1);
-    return ((unsigned(b) ^ unsigned(b >> 32)) * DeBruijn_32) >> 26;
+    return Is64Bit ? (b * DeBruijn_64) >> 58
+                   : ((unsigned(b) ^ unsigned(b >> 32)) * DeBruijn_32) >> 26;
   }
 }
 
-/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard.
-/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard.
+/// lsb()/msb() finds the least/most significant bit in a non-zero bitboard.
+/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard.
 
-#if !defined(USE_BSFQ)
+#ifndef USE_BSFQ
 
 Square lsb(Bitboard b) { return BSFTable[bsf_index(b)]; }
 
@@ -123,95 +118,79 @@ Square msb(Bitboard b) {
       result += 8;
   }
 
-  return (Square)(result + MS1BTable[b32]);
+  return Square(result + MS1BTable[b32]);
 }
 
-#endif // !defined(USE_BSFQ)
+#endif // ifndef USE_BSFQ
 
 
-/// Bitboards::print() prints a bitboard in an easily readable format to the
-/// standard output. This is sometimes useful for debugging.
+/// Bitboards::pretty() returns an ASCII representation of a bitboard to be
+/// printed to standard output. This is sometimes useful for debugging.
 
-void Bitboards::print(Bitboard b) {
+const std::string Bitboards::pretty(Bitboard b) {
 
-  sync_cout;
+  std::string s = "+---+---+---+---+---+---+---+---+\n";
 
-  for (Rank rank = RANK_8; rank >= RANK_1; rank--)
+  for (Rank r = RANK_8; r >= RANK_1; --r)
   {
-      std::cout << "+---+---+---+---+---+---+---+---+" << '\n';
+      for (File f = FILE_A; f <= FILE_H; ++f)
+          s.append(b & make_square(f, r) ? "| X " : "|   ");
 
-      for (File file = FILE_A; file <= FILE_H; file++)
-          std::cout << "| " << (b & (file | rank) ? "X " : "  ");
-
-      std::cout << "|\n";
+      s.append("|\n+---+---+---+---+---+---+---+---+\n");
   }
-  std::cout << "+---+---+---+---+---+---+---+---+" << sync_endl;
+
+  return s;
 }
 
 
-/// Bitboards::init() initializes various bitboard arrays. It is called during
-/// program initialization.
+/// Bitboards::init() initializes various bitboard tables. It is called at
+/// startup and relies on global objects to be already zero-initialized.
 
 void Bitboards::init() {
 
-  for (int k = 0, i = 0; i < 8; i++)
-      while (k < (2 << i))
-          MS1BTable[k++] = i;
+  for (Square s = SQ_A1; s <= SQ_H8; ++s)
+      BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s;
 
-  for (int i = 0; i < 64; i++)
-      BSFTable[bsf_index(1ULL << i)] = Square(i);
+  for (Bitboard b = 1; b < 256; ++b)
+      MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b);
 
-  for (Bitboard b = 0; b < 256; b++)
-      BitCount8Bit[b] = (uint8_t)popcount<Max15>(b);
+  for (File f = FILE_A; f <= FILE_H; ++f)
+      FileBB[f] = f > FILE_A ? FileBB[f - 1] << 1 : FileABB;
 
-  for (Square s = SQ_A1; s <= SQ_H8; s++)
-      SquareBB[s] = 1ULL << s;
+  for (Rank r = RANK_1; r <= RANK_8; ++r)
+      RankBB[r] = r > RANK_1 ? RankBB[r - 1] << 8 : Rank1BB;
 
-  FileBB[FILE_A] = FileABB;
-  RankBB[RANK_1] = Rank1BB;
-
-  for (int i = 1; i < 8; i++)
-  {
-      FileBB[i] = FileBB[i - 1] << 1;
-      RankBB[i] = RankBB[i - 1] << 8;
-  }
-
-  for (File f = FILE_A; f <= FILE_H; f++)
-  {
+  for (File f = FILE_A; f <= FILE_H; ++f)
       AdjacentFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0);
-      ThisAndAdjacentFilesBB[f] = FileBB[f] | AdjacentFilesBB[f];
-  }
 
-  for (Rank r = RANK_1; r < RANK_8; r++)
+  for (Rank r = RANK_1; r < RANK_8; ++r)
       InFrontBB[WHITE][r] = ~(InFrontBB[BLACK][r + 1] = InFrontBB[BLACK][r] | RankBB[r]);
 
-  for (Color c = WHITE; c <= BLACK; c++)
-      for (Square s = SQ_A1; s <= SQ_H8; s++)
+  for (Color c = WHITE; c <= BLACK; ++c)
+      for (Square s = SQ_A1; s <= SQ_H8; ++s)
       {
           ForwardBB[c][s]      = InFrontBB[c][rank_of(s)] & FileBB[file_of(s)];
-          PassedPawnMask[c][s] = InFrontBB[c][rank_of(s)] & ThisAndAdjacentFilesBB[file_of(s)];
-          AttackSpanMask[c][s] = InFrontBB[c][rank_of(s)] & AdjacentFilesBB[file_of(s)];
+          PawnAttackSpan[c][s] = InFrontBB[c][rank_of(s)] & AdjacentFilesBB[file_of(s)];
+          PassedPawnMask[c][s] = ForwardBB[c][s] | PawnAttackSpan[c][s];
       }
 
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
-      for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
-          SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2));
-
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
-      for (int d = 1; d < 8; d++)
-          for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
-              if (SquareDistance[s1][s2] == d)
-                  DistanceRingsBB[s1][d - 1] |= s2;
+  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
+      for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
+          if (s1 != s2)
+          {
+              SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2));
+              DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2;
+          }
 
   int steps[][9] = { {}, { 7, 9 }, { 17, 15, 10, 6, -6, -10, -15, -17 },
                      {}, {}, {}, { 9, 7, -7, -9, 8, 1, -1, -8 } };
 
-  for (Color c = WHITE; c <= BLACK; c++)
-      for (PieceType pt = PAWN; pt <= KING; pt++)
-          for (Square s = SQ_A1; s <= SQ_H8; s++)
-              for (int k = 0; steps[pt][k]; k++)
+  for (Color c = WHITE; c <= BLACK; ++c)
+      for (PieceType pt = PAWN; pt <= KING; ++pt)
+          for (Square s = SQ_A1; s <= SQ_H8; ++s)
+              for (int i = 0; steps[pt][i]; ++i)
               {
-                  Square to = s + Square(c == WHITE ? steps[pt][k] : -steps[pt][k]);
+                  Square to = s + Square(c == WHITE ? steps[pt][i] : -steps[pt][i]);
 
                   if (is_ok(to) && square_distance(s, to) < 3)
                       StepAttacksBB[make_piece(c, pt)][s] |= to;
@@ -223,21 +202,23 @@ void Bitboards::init() {
   init_magics(RTable, RAttacks, RMagics, RMasks, RShifts, RDeltas, magic_index<ROOK>);
   init_magics(BTable, BAttacks, BMagics, BMasks, BShifts, BDeltas, magic_index<BISHOP>);
 
-  for (Square s = SQ_A1; s <= SQ_H8; s++)
+  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
   {
-      PseudoAttacks[QUEEN][s]  = PseudoAttacks[BISHOP][s] = attacks_bb<BISHOP>(s, 0);
-      PseudoAttacks[QUEEN][s] |= PseudoAttacks[  ROOK][s] = attacks_bb<  ROOK>(s, 0);
+      PseudoAttacks[QUEEN][s1]  = PseudoAttacks[BISHOP][s1] = attacks_bb<BISHOP>(s1, 0);
+      PseudoAttacks[QUEEN][s1] |= PseudoAttacks[  ROOK][s1] = attacks_bb<  ROOK>(s1, 0);
+
+      for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
+      {
+          Piece pc = (PseudoAttacks[BISHOP][s1] & s2) ? W_BISHOP :
+                     (PseudoAttacks[ROOK][s1]   & s2) ? W_ROOK   : NO_PIECE;
+
+          if (pc == NO_PIECE)
+              continue;
+
+          LineBB[s1][s2] = (attacks_bb(pc, s1, 0) & attacks_bb(pc, s2, 0)) | s1 | s2;
+          BetweenBB[s1][s2] = attacks_bb(pc, s1, SquareBB[s2]) & attacks_bb(pc, s2, SquareBB[s1]);
+      }
   }
-
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
-      for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
-          if (PseudoAttacks[QUEEN][s1] & s2)
-          {
-              Square delta = (s2 - s1) / square_distance(s1, s2);
-
-              for (Square s = s1 + delta; s != s2; s += delta)
-                  BetweenBB[s1][s2] |= s;
-          }
 }
 
 
@@ -247,7 +228,7 @@ namespace {
 
     Bitboard attack = 0;
 
-    for (int i = 0; i < 4; i++)
+    for (int i = 0; i < 4; ++i)
         for (Square s = sq + deltas[i];
              is_ok(s) && square_distance(s, s - deltas[i]) == 1;
              s += deltas[i])
@@ -262,20 +243,6 @@ namespace {
   }
 
 
-  Bitboard pick_random(RKISS& rk, int booster) {
-
-    // Values s1 and s2 are used to rotate the candidate magic of a
-    // quantity known to be the optimal to quickly find the magics.
-    int s1 = booster & 63, s2 = (booster >> 6) & 63;
-
-    Bitboard m = rk.rand<Bitboard>();
-    m = (m >> s1) | (m << (64 - s1));
-    m &= rk.rand<Bitboard>();
-    m = (m >> s2) | (m << (64 - s2));
-    return m & rk.rand<Bitboard>();
-  }
-
-
   // 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
   // chessprogramming.wikispaces.com/Magic+Bitboards. In particular, here we
@@ -284,8 +251,9 @@ namespace {
   void init_magics(Bitboard table[], Bitboard* attacks[], Bitboard magics[],
                    Bitboard masks[], unsigned shifts[], Square deltas[], Fn index) {
 
-    int MagicBoosters[][8] = { { 3191, 2184, 1310, 3618, 2091, 1308, 2452, 3996 },
-                               { 1059, 3608,  605, 3234, 3326,   38, 2029, 3043 } };
+    int MagicBoosters[][8] = { {  969, 1976, 2850,  542, 2069, 2852, 1708,  164 },
+                               { 3101,  552, 3555,  926,  834,   26, 2131, 1117 } };
+
     RKISS rk;
     Bitboard occupancy[4096], reference[4096], edges, b;
     int i, size, booster;
@@ -293,7 +261,7 @@ namespace {
     // attacks[s] is a pointer to the beginning of the attacks table for square 's'
     attacks[SQ_A1] = table;
 
-    for (Square s = SQ_A1; s <= SQ_H8; s++)
+    for (Square s = SQ_A1; s <= SQ_H8; ++s)
     {
         // Board edges are not considered in the relevant occupancies
         edges = ((Rank1BB | Rank8BB) & ~rank_bb(s)) | ((FileABB | FileHBB) & ~file_bb(s));
@@ -311,7 +279,12 @@ namespace {
         b = size = 0;
         do {
             occupancy[size] = b;
-            reference[size++] = sliding_attack(deltas, s, b);
+            reference[size] = sliding_attack(deltas, s, b);
+
+            if (HasPext)
+                attacks[s][_pext_u64(b, masks[s])] = reference[size];
+
+            size++;
             b = (b - masks[s]) & masks[s];
         } while (b);
 
@@ -320,32 +293,35 @@ namespace {
         if (s < SQ_H8)
             attacks[s + 1] = attacks[s] + size;
 
+        if (HasPext)
+            continue;
+
         booster = MagicBoosters[Is64Bit][rank_of(s)];
 
         // Find a magic for square 's' picking up an (almost) random number
         // until we find the one that passes the verification test.
         do {
-            do magics[s] = pick_random(rk, booster);
-            while (BitCount8Bit[(magics[s] * masks[s]) >> 56] < 6);
+            do magics[s] = rk.magic_rand<Bitboard>(booster);
+            while (popcount<Max15>((magics[s] * masks[s]) >> 56) < 6);
 
-            memset(attacks[s], 0, size * sizeof(Bitboard));
+            std::memset(attacks[s], 0, size * sizeof(Bitboard));
 
             // A good magic must map every possible occupancy to an index that
             // looks up the correct sliding attack in the attacks[s] database.
             // Note that we build up the database for square 's' as a side
             // effect of verifying the magic.
-            for (i = 0; i < size; i++)
+            for (i = 0; i < size; ++i)
             {
                 Bitboard& attack = attacks[s][index(s, occupancy[i])];
 
                 if (attack && attack != reference[i])
                     break;
 
-                assert(reference[i] != 0);
+                assert(reference[i]);
 
                 attack = reference[i];
             }
-        } while (i != size);
+        } while (i < size);
     }
   }
 }

src/bitboard.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,7 +18,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(BITBOARD_H_INCLUDED)
+#ifndef BITBOARD_H_INCLUDED
 #define BITBOARD_H_INCLUDED
 
 #include "types.h"
@@ -26,43 +26,64 @@
 namespace Bitboards {
 
 void init();
-void print(Bitboard b);
+const std::string pretty(Bitboard b);
 
 }
 
 namespace Bitbases {
 
 void init_kpk();
-uint32_t probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm);
+bool probe_kpk(Square wksq, Square wpsq, Square bksq, Color us);
 
 }
 
+const Bitboard FileABB = 0x0101010101010101ULL;
+const Bitboard FileBBB = FileABB << 1;
+const Bitboard FileCBB = FileABB << 2;
+const Bitboard FileDBB = FileABB << 3;
+const Bitboard FileEBB = FileABB << 4;
+const Bitboard FileFBB = FileABB << 5;
+const Bitboard FileGBB = FileABB << 6;
+const Bitboard FileHBB = FileABB << 7;
+
+const Bitboard Rank1BB = 0xFF;
+const Bitboard Rank2BB = Rank1BB << (8 * 1);
+const Bitboard Rank3BB = Rank1BB << (8 * 2);
+const Bitboard Rank4BB = Rank1BB << (8 * 3);
+const Bitboard Rank5BB = Rank1BB << (8 * 4);
+const Bitboard Rank6BB = Rank1BB << (8 * 5);
+const Bitboard Rank7BB = Rank1BB << (8 * 6);
+const Bitboard Rank8BB = Rank1BB << (8 * 7);
+
 CACHE_LINE_ALIGNMENT
 
-extern Bitboard RMasks[64];
-extern Bitboard RMagics[64];
-extern Bitboard* RAttacks[64];
-extern unsigned RShifts[64];
+extern Bitboard RMasks[SQUARE_NB];
+extern Bitboard RMagics[SQUARE_NB];
+extern Bitboard* RAttacks[SQUARE_NB];
+extern unsigned RShifts[SQUARE_NB];
 
-extern Bitboard BMasks[64];
-extern Bitboard BMagics[64];
-extern Bitboard* BAttacks[64];
-extern unsigned BShifts[64];
+extern Bitboard BMasks[SQUARE_NB];
+extern Bitboard BMagics[SQUARE_NB];
+extern Bitboard* BAttacks[SQUARE_NB];
+extern unsigned BShifts[SQUARE_NB];
 
-extern Bitboard SquareBB[64];
-extern Bitboard FileBB[8];
-extern Bitboard RankBB[8];
-extern Bitboard AdjacentFilesBB[8];
-extern Bitboard ThisAndAdjacentFilesBB[8];
-extern Bitboard InFrontBB[2][8];
-extern Bitboard StepAttacksBB[16][64];
-extern Bitboard BetweenBB[64][64];
-extern Bitboard DistanceRingsBB[64][8];
-extern Bitboard ForwardBB[2][64];
-extern Bitboard PassedPawnMask[2][64];
-extern Bitboard AttackSpanMask[2][64];
-extern Bitboard PseudoAttacks[6][64];
+extern Bitboard SquareBB[SQUARE_NB];
+extern Bitboard FileBB[FILE_NB];
+extern Bitboard RankBB[RANK_NB];
+extern Bitboard AdjacentFilesBB[FILE_NB];
+extern Bitboard InFrontBB[COLOR_NB][RANK_NB];
+extern Bitboard StepAttacksBB[PIECE_NB][SQUARE_NB];
+extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
+extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
+extern Bitboard DistanceRingsBB[SQUARE_NB][8];
+extern Bitboard ForwardBB[COLOR_NB][SQUARE_NB];
+extern Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB];
+extern Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB];
+extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 
+extern int SquareDistance[SQUARE_NB][SQUARE_NB];
+
+const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
 
 /// 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.
@@ -87,13 +108,34 @@ inline Bitboard operator^(Bitboard b, Square s) {
   return b ^ SquareBB[s];
 }
 
-
-/// more_than_one() returns true if in 'b' there is more than one bit set
-
 inline bool more_than_one(Bitboard b) {
   return b & (b - 1);
 }
 
+inline int square_distance(Square s1, Square s2) {
+  return SquareDistance[s1][s2];
+}
+
+inline int file_distance(Square s1, Square s2) {
+  return abs(file_of(s1) - file_of(s2));
+}
+
+inline int rank_distance(Square s1, Square s2) {
+  return abs(rank_of(s1) - rank_of(s2));
+}
+
+
+/// shift_bb() moves bitboard one step along direction Delta. Mainly for pawns.
+
+template<Square Delta>
+inline Bitboard shift_bb(Bitboard b) {
+
+  return  Delta == DELTA_N  ?  b             << 8 : Delta == DELTA_S  ?  b             >> 8
+        : Delta == DELTA_NE ? (b & ~FileHBB) << 9 : Delta == DELTA_SE ? (b & ~FileHBB) >> 7
+        : Delta == DELTA_NW ? (b & ~FileABB) << 7 : Delta == DELTA_SW ? (b & ~FileABB) >> 9
+        : 0;
+}
+
 
 /// rank_bb() and file_bb() take a file or a square as input and return
 /// a bitboard representing all squares on the given file or rank.
@@ -115,7 +157,7 @@ inline Bitboard file_bb(Square s) {
 }
 
 
-/// adjacent_files_bb takes a file as input and returns a bitboard representing
+/// adjacent_files_bb() takes a file as input and returns a bitboard representing
 /// all squares on the adjacent files.
 
 inline Bitboard adjacent_files_bb(File f) {
@@ -123,32 +165,19 @@ inline Bitboard adjacent_files_bb(File f) {
 }
 
 
-/// this_and_adjacent_files_bb takes a file as input and returns a bitboard
-/// representing all squares on the given and adjacent files.
-
-inline Bitboard this_and_adjacent_files_bb(File f) {
-  return ThisAndAdjacentFilesBB[f];
-}
-
-
-/// in_front_bb() takes a color and a rank or square as input, and returns a
-/// bitboard representing all the squares on all ranks in front of the rank
-/// (or square), from the given color's point of view.  For instance,
-/// in_front_bb(WHITE, RANK_5) will give all squares on ranks 6, 7 and 8, while
-/// in_front_bb(BLACK, SQ_D3) will give all squares on ranks 1 and 2.
+/// in_front_bb() takes a color and a rank as input, and returns a bitboard
+/// representing all the squares on all ranks in front of the rank, from the
+/// given color's point of view. For instance, in_front_bb(BLACK, RANK_3) will
+/// give all squares on ranks 1 and 2.
 
 inline Bitboard in_front_bb(Color c, Rank r) {
   return InFrontBB[c][r];
 }
 
-inline Bitboard in_front_bb(Color c, Square s) {
-  return InFrontBB[c][rank_of(s)];
-}
 
-
-/// between_bb returns a bitboard representing all squares between two squares.
+/// between_bb() returns a bitboard representing all squares between two squares.
 /// For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with the bits for
-/// square d5 and e6 set.  If s1 and s2 are not on the same line, file or diagonal,
+/// square d5 and e6 set.  If s1 and s2 are not on the same rank, file or diagonal,
 /// 0 is returned.
 
 inline Bitboard between_bb(Square s1, Square s2) {
@@ -156,7 +185,7 @@ inline Bitboard between_bb(Square s1, Square s2) {
 }
 
 
-/// forward_bb takes a color and a square as input, and returns a bitboard
+/// forward_bb() takes a color and a square as input, and returns a bitboard
 /// representing all squares along the line in front of the square, from the
 /// point of view of the given color. Definition of the table is:
 /// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s)
@@ -166,41 +195,39 @@ inline Bitboard forward_bb(Color c, Square s) {
 }
 
 
-/// passed_pawn_mask takes a color and a square as input, and returns a
+/// pawn_attack_span() takes a color and a square as input, and returns a bitboard
+/// representing all squares that can be attacked by a pawn of the given color
+/// when it moves along its file starting from the given square. Definition is:
+/// PawnAttackSpan[c][s] = in_front_bb(c, s) & adjacent_files_bb(s);
+
+inline Bitboard pawn_attack_span(Color c, Square s) {
+  return PawnAttackSpan[c][s];
+}
+
+
+/// passed_pawn_mask() takes a color and a square as input, and returns a
 /// bitboard mask which can be used to test if a pawn of the given color on
 /// the given square is a passed pawn. Definition of the table is:
-/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(s)
+/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_bb(c, s)
 
 inline Bitboard passed_pawn_mask(Color c, Square s) {
   return PassedPawnMask[c][s];
 }
 
 
-/// attack_span_mask takes a color and a square as input, and returns a bitboard
-/// representing all squares that can be attacked by a pawn of the given color
-/// when it moves along its file starting from the given square. Definition is:
-/// AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(s);
+/// squares_of_color() returns a bitboard representing all squares with the same
+/// color of the given square.
 
-inline Bitboard attack_span_mask(Color c, Square s) {
-  return AttackSpanMask[c][s];
+inline Bitboard squares_of_color(Square s) {
+  return DarkSquares & s ? DarkSquares : ~DarkSquares;
 }
 
 
-/// squares_aligned returns true if the squares s1, s2 and s3 are aligned
+/// aligned() returns true if the squares s1, s2 and s3 are aligned
 /// either on a straight or on a diagonal line.
 
-inline bool squares_aligned(Square s1, Square s2, Square s3) {
-  return  (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3])
-        & (     SquareBB[s1] |      SquareBB[s2] |      SquareBB[s3]);
-}
-
-
-/// same_color_squares() returns a bitboard representing all squares with
-/// the same color of the given square.
-
-inline Bitboard same_color_squares(Square s) {
-  return Bitboard(0xAA55AA55AA55AA55ULL) & s ?  0xAA55AA55AA55AA55ULL
-                                             : ~0xAA55AA55AA55AA55ULL;
+inline bool aligned(Square s1, Square s2, Square s3) {
+  return LineBB[s1][s2] & s3;
 }
 
 
@@ -214,6 +241,9 @@ FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) {
   Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
   unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
 
+  if (HasPext)
+      return unsigned(_pext_u64(occ, Masks[s]));
+
   if (Is64Bit)
       return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
 
@@ -227,49 +257,74 @@ inline Bitboard attacks_bb(Square s, Bitboard occ) {
   return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index<Pt>(s, occ)];
 }
 
+inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occ) {
 
-/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard.
-/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard.
+  switch (type_of(pc))
+  {
+  case BISHOP: return attacks_bb<BISHOP>(s, occ);
+  case ROOK  : return attacks_bb<ROOK>(s, occ);
+  case QUEEN : return attacks_bb<BISHOP>(s, occ) | attacks_bb<ROOK>(s, occ);
+  default    : return StepAttacksBB[pc][s];
+  }
+}
 
-#if defined(USE_BSFQ)
+/// lsb()/msb() finds the least/most significant bit in a non-zero bitboard.
+/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard.
+
+#ifdef USE_BSFQ
 
 #  if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
 
 FORCE_INLINE Square lsb(Bitboard b) {
-  unsigned long index;
-  _BitScanForward64(&index, b);
-  return (Square) index;
+  unsigned long idx;
+  _BitScanForward64(&idx, b);
+  return (Square) idx;
 }
 
 FORCE_INLINE Square msb(Bitboard b) {
-  unsigned long index;
-  _BitScanReverse64(&index, b);
-  return (Square) index;
+  unsigned long idx;
+  _BitScanReverse64(&idx, b);
+  return (Square) idx;
+}
+
+#  elif defined(__arm__)
+
+FORCE_INLINE int lsb32(uint32_t v) {
+  __asm__("rbit %0, %1" : "=r"(v) : "r"(v));
+  return __builtin_clz(v);
+}
+
+FORCE_INLINE Square msb(Bitboard b) {
+  return (Square) (63 - __builtin_clzll(b));
+}
+
+FORCE_INLINE Square lsb(Bitboard b) {
+  return (Square) (uint32_t(b) ? lsb32(uint32_t(b)) : 32 + lsb32(uint32_t(b >> 32)));
 }
 
 #  else
 
 FORCE_INLINE Square lsb(Bitboard b) { // Assembly code by Heinz van Saanen
-  Bitboard index;
-  __asm__("bsfq %1, %0": "=r"(index): "rm"(b) );
-  return (Square) index;
+  Bitboard idx;
+  __asm__("bsfq %1, %0": "=r"(idx): "rm"(b) );
+  return (Square) idx;
 }
 
 FORCE_INLINE Square msb(Bitboard b) {
-  Bitboard index;
-  __asm__("bsrq %1, %0": "=r"(index): "rm"(b) );
-  return (Square) index;
+  Bitboard idx;
+  __asm__("bsrq %1, %0": "=r"(idx): "rm"(b) );
+  return (Square) idx;
 }
 
 #  endif
 
 FORCE_INLINE Square pop_lsb(Bitboard* b) {
   const Square s = lsb(*b);
-  *b &= ~(1ULL << s);
+  *b &= *b - 1;
   return s;
 }
 
-#else // if !defined(USE_BSFQ)
+#else // if defined(USE_BSFQ)
 
 extern Square msb(Bitboard b);
 extern Square lsb(Bitboard b);
@@ -277,4 +332,10 @@ extern Square pop_lsb(Bitboard* b);
 
 #endif
 
-#endif // !defined(BITBOARD_H_INCLUDED)
+/// frontmost_sq() and backmost_sq() find the square corresponding to the
+/// most/least advanced bit relative to the given color.
+
+inline Square frontmost_sq(Color c, Bitboard b) { return c == WHITE ? msb(b) : lsb(b); }
+inline Square  backmost_sq(Color c, Bitboard b) { return c == WHITE ? lsb(b) : msb(b); }
+
+#endif // #ifndef BITBOARD_H_INCLUDED

src/bitcount.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,7 +18,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(BITCOUNT_H_INCLUDED)
+#ifndef BITCOUNT_H_INCLUDED
 #define BITCOUNT_H_INCLUDED
 
 #include <cassert>
@@ -32,62 +32,56 @@ enum BitCountType {
   CNT_HW_POPCNT
 };
 
-/// Determine at compile time the best popcount<> specialization according if
-/// platform is 32 or 64 bits, to the maximum number of nonzero bits to count or
-/// use hardware popcnt instruction when available.
+/// Determine at compile time the best popcount<> specialization according to
+/// whether the platform is 32 or 64 bit, the maximum number of non-zero
+/// bits to count and if the hardware popcnt instruction is available.
 const BitCountType Full  = HasPopCnt ? CNT_HW_POPCNT : Is64Bit ? CNT_64 : CNT_32;
 const BitCountType Max15 = HasPopCnt ? CNT_HW_POPCNT : Is64Bit ? CNT_64_MAX15 : CNT_32_MAX15;
 
 
-/// popcount() counts the number of nonzero bits in a bitboard
+/// popcount() counts the number of non-zero bits in a bitboard
 template<BitCountType> inline int popcount(Bitboard);
 
 template<>
 inline int popcount<CNT_64>(Bitboard b) {
-  b -= ((b>>1) & 0x5555555555555555ULL);
-  b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
-  b = ((b>>4) + b) & 0x0F0F0F0F0F0F0F0FULL;
-  b *= 0x0101010101010101ULL;
-  return int(b >> 56);
+  b -=  (b >> 1) & 0x5555555555555555ULL;
+  b  = ((b >> 2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
+  b  = ((b >> 4) + b) & 0x0F0F0F0F0F0F0F0FULL;
+  return (b * 0x0101010101010101ULL) >> 56;
 }
 
 template<>
 inline int popcount<CNT_64_MAX15>(Bitboard b) {
-  b -= (b>>1) & 0x5555555555555555ULL;
-  b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
-  b *= 0x1111111111111111ULL;
-  return int(b >> 60);
+  b -=  (b >> 1) & 0x5555555555555555ULL;
+  b  = ((b >> 2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
+  return (b * 0x1111111111111111ULL) >> 60;
 }
 
 template<>
 inline int popcount<CNT_32>(Bitboard b) {
   unsigned w = unsigned(b >> 32), v = unsigned(b);
-  v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits
-  w -= (w >> 1) & 0x55555555;
-  v = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits
-  w = ((w >> 2) & 0x33333333) + (w & 0x33333333);
-  v = ((v >> 4) + v) & 0x0F0F0F0F; // 0-8 in 8 bits
-  v += (((w >> 4) + w) & 0x0F0F0F0F);  // 0-16 in 8 bits
-  v *= 0x01010101; // mul is fast on amd procs
-  return int(v >> 24);
+  v -=  (v >> 1) & 0x55555555; // 0-2 in 2 bits
+  w -=  (w >> 1) & 0x55555555;
+  v  = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits
+  w  = ((w >> 2) & 0x33333333) + (w & 0x33333333);
+  v  = ((v >> 4) + v + (w >> 4) + w) & 0x0F0F0F0F;
+  return (v * 0x01010101) >> 24;
 }
 
 template<>
 inline int popcount<CNT_32_MAX15>(Bitboard b) {
   unsigned w = unsigned(b >> 32), v = unsigned(b);
-  v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits
-  w -= (w >> 1) & 0x55555555;
-  v = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits
-  w = ((w >> 2) & 0x33333333) + (w & 0x33333333);
-  v += w; // 0-8 in 4 bits
-  v *= 0x11111111;
-  return int(v >> 28);
+  v -=  (v >> 1) & 0x55555555; // 0-2 in 2 bits
+  w -=  (w >> 1) & 0x55555555;
+  v  = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits
+  w  = ((w >> 2) & 0x33333333) + (w & 0x33333333);
+  return ((v + w) * 0x11111111) >> 28;
 }
 
 template<>
 inline int popcount<CNT_HW_POPCNT>(Bitboard b) {
 
-#if !defined(USE_POPCNT)
+#ifndef USE_POPCNT
 
   assert(false);
   return b != 0; // Avoid 'b not used' warning
@@ -102,11 +96,10 @@ inline int popcount<CNT_HW_POPCNT>(Bitboard b) {
 
 #else
 
-  unsigned long ret;
-  __asm__("popcnt %1, %0" : "=r" (ret) : "r" (b));
-  return ret;
+  __asm__("popcnt %1, %0" : "=r" (b) : "r" (b));
+  return b;
 
 #endif
 }
 
-#endif // !defined(BITCOUNT_H_INCLUDED)
+#endif // #ifndef BITCOUNT_H_INCLUDED

src/book.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -25,7 +25,6 @@
 
 #include <algorithm>
 #include <cassert>
-#include <iostream>
 
 #include "book.h"
 #include "misc.h"
@@ -36,9 +35,9 @@ using namespace std;
 namespace {
 
   // A Polyglot book is a series of "entries" of 16 bytes. All integers are
-  // stored in big-endian format, with highest byte first (regardless of size).
-  // The entries are ordered according to the key in ascending order.
-  struct BookEntry {
+  // stored in big-endian format, with the highest byte first (regardless of
+  // size). The entries are ordered according to the key in ascending order.
+  struct Entry {
     uint64_t key;
     uint16_t move;
     uint16_t count;
@@ -46,7 +45,15 @@ namespace {
   };
 
   // Random numbers from PolyGlot, used to compute book hash keys
-  const Key PolyGlotRandoms[781] = {
+  const union {
+    Key PolyGlotRandoms[781];
+    struct {
+      Key psq[12][64];  // [piece][square]
+      Key castling[4];  // [castling flag]
+      Key enpassant[8]; // [file]
+      Key turn;
+    } Zobrist;
+  } PG = {{
     0x9D39247E33776D41ULL, 0x2AF7398005AAA5C7ULL, 0x44DB015024623547ULL,
     0x9C15F73E62A76AE2ULL, 0x75834465489C0C89ULL, 0x3290AC3A203001BFULL,
     0x0FBBAD1F61042279ULL, 0xE83A908FF2FB60CAULL, 0x0D7E765D58755C10ULL,
@@ -308,75 +315,64 @@ namespace {
     0x003A93D8B2806962ULL, 0x1C99DED33CB890A1ULL, 0xCF3145DE0ADD4289ULL,
     0xD0E4427A5514FB72ULL, 0x77C621CC9FB3A483ULL, 0x67A34DAC4356550BULL,
     0xF8D626AAAF278509ULL
-  };
+  }};
 
-  // Offsets to the PolyGlotRandoms[] array of zobrist keys
-  const Key* ZobPiece     = PolyGlotRandoms;
-  const Key* ZobCastle    = ZobPiece     + 12 * 64; // Pieces * squares
-  const Key* ZobEnPassant = ZobCastle    + 4;       // Castle flags
-  const Key* ZobTurn      = ZobEnPassant + 8;       // Number of files
+  // polyglot_key() returns the PolyGlot hash key of the given position
+  Key polyglot_key(const Position& pos) {
 
-  // book_key() returns the PolyGlot hash key of the given position
-  uint64_t book_key(const Position& pos) {
-
-    uint64_t key = 0;
+    Key key = 0;
     Bitboard b = pos.pieces();
 
     while (b)
     {
-        // In PolyGlotRandoms[] pieces are stored in the following sequence:
-        // BP = 0, WP = 1, BN = 2, WN = 3, ... BK = 10, WK = 11
         Square s = pop_lsb(&b);
-        Piece p = pos.piece_on(s);
-        int pieceOfs = 2 * (type_of(p) - 1) + (color_of(p) == WHITE);
-        key ^= ZobPiece[64 * pieceOfs + s];
+        Piece pc = pos.piece_on(s);
+
+        // PolyGlot pieces are: BP = 0, WP = 1, BN = 2, ... BK = 10, WK = 11
+        key ^= PG.Zobrist.psq[2 * (type_of(pc) - 1) + (color_of(pc) == WHITE)][s];
     }
 
-    b = pos.can_castle(ALL_CASTLES);
+    b = pos.can_castle(ANY_CASTLING);
 
     while (b)
-        key ^= ZobCastle[pop_lsb(&b)];
+        key ^= PG.Zobrist.castling[pop_lsb(&b)];
 
     if (pos.ep_square() != SQ_NONE)
-        key ^= ZobEnPassant[file_of(pos.ep_square())];
+        key ^= PG.Zobrist.enpassant[file_of(pos.ep_square())];
 
     if (pos.side_to_move() == WHITE)
-        key ^= ZobTurn[0];
+        key ^= PG.Zobrist.turn;
 
     return key;
   }
 
 } // namespace
 
-PolyglotBook::PolyglotBook() {
-
-  for (int i = Time::now() % 10000; i > 0; i--)
-      RKiss.rand<unsigned>(); // Make random number generation less deterministic
-}
+PolyglotBook::PolyglotBook() : rkiss(Time::now() % 10000) {}
 
 PolyglotBook::~PolyglotBook() { if (is_open()) close(); }
 
 
 /// operator>>() reads sizeof(T) chars from the file's binary byte stream and
-/// converts them in a number of type T. A Polyglot book stores numbers in
+/// converts them into a number of type T. A Polyglot book stores numbers in
 /// big-endian format.
 
 template<typename T> PolyglotBook& PolyglotBook::operator>>(T& n) {
 
   n = 0;
-  for (size_t i = 0; i < sizeof(T); i++)
+  for (size_t i = 0; i < sizeof(T); ++i)
       n = T((n << 8) + ifstream::get());
 
   return *this;
 }
 
-template<> PolyglotBook& PolyglotBook::operator>>(BookEntry& e) {
+template<> PolyglotBook& PolyglotBook::operator>>(Entry& e) {
   return *this >> e.key >> e.move >> e.count >> e.learn;
 }
 
 
 /// open() tries to open a book file with the given name after closing any
-/// exsisting one.
+/// existing one.
 
 bool PolyglotBook::open(const char* fName) {
 
@@ -386,37 +382,38 @@ bool PolyglotBook::open(const char* fName) {
   ifstream::open(fName, ifstream::in | ifstream::binary);
 
   fileName = is_open() ? fName : "";
-  ifstream::clear(); // Reset any error flag to allow retry ifstream::open()
+  ifstream::clear(); // Reset any error flag to allow a retry ifstream::open()
   return !fileName.empty();
 }
 
 
 /// probe() tries to find a book move for the given position. If no move is
-/// found returns MOVE_NONE. If pickBest is true returns always the highest
-/// rated move, otherwise randomly chooses one, based on the move score.
+/// found, it returns MOVE_NONE. If pickBest is true, then it always returns
+/// the highest-rated move, otherwise it randomly chooses one based on the
+/// move score.
 
 Move PolyglotBook::probe(const Position& pos, const string& fName, bool pickBest) {
 
   if (fileName != fName && !open(fName.c_str()))
       return MOVE_NONE;
 
-  BookEntry e;
+  Entry e;
   uint16_t best = 0;
   unsigned sum = 0;
   Move move = MOVE_NONE;
-  uint64_t key = book_key(pos);
+  Key key = polyglot_key(pos);
 
-  seekg(find_first(key) * sizeof(BookEntry), ios_base::beg);
+  seekg(find_first(key) * sizeof(Entry), ios_base::beg);
 
   while (*this >> e, e.key == key && good())
   {
       best = max(best, e.count);
       sum += e.count;
 
-      // Choose book move according to its score. If a move has a very
-      // high score it has higher probability to be choosen than a move
-      // with lower score. Note that first entry is always chosen.
-      if (   (sum && RKiss.rand<unsigned>() % sum < e.count)
+      // Choose book move according to its score. If a move has a very high
+      // score it has a higher probability of being choosen than a move with
+      // a lower score. Note that first entry is always chosen.
+      if (   (!pickBest && sum && rkiss.rand<unsigned>() % sum < e.count)
           || (pickBest && e.count == best))
           move = Move(e.move);
   }
@@ -430,18 +427,18 @@ Move PolyglotBook::probe(const Position& pos, const string& fName, bool pickBest
   // bit  6-11: origin square (from 0 to 63)
   // bit 12-14: promotion piece (from KNIGHT == 1 to QUEEN == 4)
   //
-  // Castling moves follow "king captures rook" representation. So in case book
-  // move is a promotion we have to convert to our representation, in all the
-  // other cases we can directly compare with a Move after having masked out
-  // the special Move's flags (bit 14-15) that are not supported by PolyGlot.
+  // Castling moves follow the "king captures rook" representation. If a book
+  // move is a promotion, we have to convert it to our representation and in
+  // all other cases, we can directly compare with a Move after having masked
+  // out the special Move flags (bit 14-15) that are not supported by PolyGlot.
   int pt = (move >> 12) & 7;
   if (pt)
       move = make<PROMOTION>(from_sq(move), to_sq(move), PieceType(pt + 1));
 
   // Add 'special move' flags and verify it is legal
-  for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
-      if (move == (ml.move() & 0x3FFF))
-          return ml.move();
+  for (MoveList<LEGAL> it(pos); *it; ++it)
+      if (move == (*it ^ type_of(*it)))
+          return *it;
 
   return MOVE_NONE;
 }
@@ -451,12 +448,12 @@ Move PolyglotBook::probe(const Position& pos, const string& fName, bool pickBest
 /// the book file for the given key. Returns the index of the leftmost book
 /// entry with the same key as the input.
 
-size_t PolyglotBook::find_first(uint64_t key) {
+size_t PolyglotBook::find_first(Key key) {
 
   seekg(0, ios::end); // Move pointer to end, so tellg() gets file's size
 
-  size_t low = 0, mid, high = (size_t)tellg() / sizeof(BookEntry) - 1;
-  BookEntry e;
+  size_t low = 0, mid, high = (size_t)tellg() / sizeof(Entry) - 1;
+  Entry e;
 
   assert(low <= high);
 
@@ -466,7 +463,7 @@ size_t PolyglotBook::find_first(uint64_t key) {
 
       assert(mid >= low && mid < high);
 
-      seekg(mid * sizeof(BookEntry), ios_base::beg);
+      seekg(mid * sizeof(Entry), ios_base::beg);
       *this >> e;
 
       if (key <= e.key)

src/book.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(BOOK_H_INCLUDED)
+#ifndef BOOK_H_INCLUDED
 #define BOOK_H_INCLUDED
 
 #include <fstream>
@@ -36,10 +36,10 @@ private:
   template<typename T> PolyglotBook& operator>>(T& n);
 
   bool open(const char* fName);
-  size_t find_first(uint64_t key);
+  size_t find_first(Key key);
 
-  RKISS RKiss;
+  RKISS rkiss;
   std::string fileName;
 };
 
-#endif // !defined(BOOK_H_INCLUDED)
+#endif // #ifndef BOOK_H_INCLUDED

src/endgame.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(ENDGAME_H_INCLUDED)
+#ifndef ENDGAME_H_INCLUDED
 #define ENDGAME_H_INCLUDED
 
 #include <map>
@@ -33,37 +33,38 @@ enum EndgameType {
 
   // Evaluation functions
 
+  KNNK,  // KNN vs K
   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
-  KBBKN, // KBB vs KN
-  KNNK,  // KNN vs K
-  KmmKm, // K and two minors vs K and one or two minors
 
 
   // Scaling functions
   SCALE_FUNS,
 
-  KBPsK,   // KB+pawns vs K
-  KQKRPs,  // KQ vs KR+pawns
+  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,    // King and pawns vs king
+  KPsK,    // K and pawns vs K
   KBPKB,   // KBP vs KB
   KBPPKB,  // KBPP vs KB
   KBPKN,   // KBP vs KN
   KNPK,    // KNP vs K
+  KNPKB,   // KNP vs KB
   KPKP     // KP vs KP
 };
 
 
-/// Endgame functions can be of two types according if return a Value or a
-/// ScaleFactor. Type eg_fun<int>::type equals to either ScaleFactor or Value
-/// depending if the template parameter is 0 or 1.
+/// Endgame functions can be of two types depending on whether they return a
+/// Value or a ScaleFactor. Type eg_fun<int>::type returns either ScaleFactor
+/// or Value depending on whether the template parameter is 0 or 1.
 
 template<int> struct eg_fun { typedef Value type; };
 template<> struct eg_fun<1> { typedef ScaleFactor type; };
@@ -83,18 +84,18 @@ struct EndgameBase {
 template<EndgameType E, typename T = typename eg_fun<(E > SCALE_FUNS)>::type>
 struct Endgame : public EndgameBase<T> {
 
-  explicit Endgame(Color c) : strongerSide(c), weakerSide(~c) {}
-  Color color() const { return strongerSide; }
+  explicit Endgame(Color c) : strongSide(c), weakSide(~c) {}
+  Color color() const { return strongSide; }
   T operator()(const Position&) const;
 
 private:
-  Color strongerSide, weakerSide;
+  const Color strongSide, weakSide;
 };
 
 
-/// Endgames class stores in two std::map the pointers to endgame evaluation
-/// and scaling base objects. Then we use polymorphism to invoke the actual
-/// endgame function calling its operator() that is virtual.
+/// The Endgames class stores the pointers to endgame evaluation and scaling
+/// base objects in two std::map typedefs. We then use polymorphism to invoke
+/// the actual endgame function by calling its virtual operator().
 
 class Endgames {
 
@@ -111,10 +112,10 @@ class Endgames {
 
 public:
   Endgames();
-  ~Endgames();
+ ~Endgames();
 
   template<typename T> T probe(Key key, T& eg)
   { return eg = map(eg).count(key) ? map(eg)[key] : NULL; }
 };
 
-#endif // !defined(ENDGAME_H_INCLUDED)
+#endif // #ifndef ENDGAME_H_INCLUDED

src/evaluate.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(EVALUATE_H_INCLUDED)
+#ifndef EVALUATE_H_INCLUDED
 #define EVALUATE_H_INCLUDED
 
 #include "types.h"
@@ -26,12 +26,10 @@ class Position;
 
 namespace Eval {
 
-extern Color RootColor;
-
 extern void init();
-extern Value evaluate(const Position& pos, Value& margin);
+extern Value evaluate(const Position& pos);
 extern std::string trace(const Position& pos);
 
 }
 
-#endif // !defined(EVALUATE_H_INCLUDED)
+#endif // #ifndef EVALUATE_H_INCLUDED

src/history.h

@@ -1,72 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
-
-  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/>.
-*/
-
-#if !defined(HISTORY_H_INCLUDED)
-#define HISTORY_H_INCLUDED
-
-#include <algorithm>
-#include <cstring>
-
-#include "types.h"
-
-/// The History class stores statistics about how often different moves
-/// have been successful or unsuccessful during the current search. These
-/// statistics are used for reduction and move ordering decisions. History
-/// entries are stored according only to moving piece and destination square,
-/// in particular two moves with different origin but same destination and
-/// same piece will be considered identical.
-
-class History {
-
-public:
-  void clear();
-  Value value(Piece p, Square to) const;
-  void add(Piece p, Square to, Value bonus);
-  Value gain(Piece p, Square to) const;
-  void update_gain(Piece p, Square to, Value g);
-
-  static const Value MaxValue = Value(2000);
-
-private:
-  Value history[16][64];  // [piece][to_square]
-  Value maxGains[16][64]; // [piece][to_square]
-};
-
-inline void History::clear() {
-  memset(history,  0, 16 * 64 * sizeof(Value));
-  memset(maxGains, 0, 16 * 64 * sizeof(Value));
-}
-
-inline Value History::value(Piece p, Square to) const {
-  return history[p][to];
-}
-
-inline void History::add(Piece p, Square to, Value bonus) {
-  if (abs(history[p][to] + bonus) < MaxValue) history[p][to] += bonus;
-}
-
-inline Value History::gain(Piece p, Square to) const {
-  return maxGains[p][to];
-}
-
-inline void History::update_gain(Piece p, Square to, Value g) {
-  maxGains[p][to] = std::max(g, maxGains[p][to] - 1);
-}
-
-#endif // !defined(HISTORY_H_INCLUDED)

src/main.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,7 +18,6 @@
 */
 
 #include <iostream>
-#include <string>
 
 #include "bitboard.h"
 #include "evaluate.h"
@@ -34,19 +33,15 @@ int main(int argc, char* argv[]) {
 
   UCI::init(Options);
   Bitboards::init();
-  Zobrist::init();
+  Position::init();
   Bitbases::init_kpk();
   Search::init();
+  Pawns::init();
   Eval::init();
   Threads.init();
-  TT.set_size(Options["Hash"]);
+  TT.resize(Options["Hash"]);
 
-  std::string args;
-
-  for (int i = 1; i < argc; i++)
-      args += std::string(argv[i]) + " ";
-
-  UCI::loop(args);
+  UCI::loop(argc, argv);
 
   Threads.exit();
 }

src/material.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <algorithm>
+#include <algorithm>  // For std::min
 #include <cassert>
 #include <cstring>
 
@@ -27,30 +27,35 @@ using namespace std;
 
 namespace {
 
-  // Values modified by Joona Kiiski
-  const Value MidgameLimit = Value(15581);
-  const Value EndgameLimit = Value(3998);
-
-  // Scale factors used when one side has no more pawns
-  const int NoPawnsSF[4] = { 6, 12, 32 };
-
   // Polynomial material balance parameters
-  const Value RedundantQueenPenalty = Value(320);
-  const Value RedundantRookPenalty  = Value(554);
 
-  const int LinearCoefficients[6] = { 1617, -162, -1172, -190, 105, 26 };
+  //                                  pair  pawn knight bishop rook queen
+  const int LinearCoefficients[6] = { 1852, -162, -1122, -183,  249, -154 };
 
-  const int QuadraticCoefficientsSameColor[][8] = {
-  { 7, 7, 7, 7, 7, 7 }, { 39, 2, 7, 7, 7, 7 }, { 35, 271, -4, 7, 7, 7 },
-  { 7, 25, 4, 7, 7, 7 }, { -27, -2, 46, 100, 56, 7 }, { 58, 29, 83, 148, -3, -25 } };
+  const int QuadraticCoefficientsSameSide[][PIECE_TYPE_NB] = {
+    //            OUR PIECES
+    // pair pawn knight bishop rook queen
+    {   0                               }, // Bishop pair
+    {  39,    2                         }, // Pawn
+    {  35,  271,  -4                    }, // knight      OUR PIECES
+    {   0,  105,   4,    0              }, // Bishop
+    { -27,   -2,  46,   100,  -141      }, // Rook
+    {-177,   25, 129,   142,  -137,   0 }  // Queen
+  };
 
-  const int QuadraticCoefficientsOppositeColor[][8] = {
-  { 41, 41, 41, 41, 41, 41 }, { 37, 41, 41, 41, 41, 41 }, { 10, 62, 41, 41, 41, 41 },
-  { 57, 64, 39, 41, 41, 41 }, { 50, 40, 23, -22, 41, 41 }, { 106, 101, 3, 151, 171, 41 } };
+  const int QuadraticCoefficientsOppositeSide[][PIECE_TYPE_NB] = {
+    //           THEIR PIECES
+    // pair pawn knight bishop rook queen
+    {   0                               }, // Bishop pair
+    {  37,    0                         }, // Pawn
+    {  10,   62,   0                    }, // Knight      OUR PIECES
+    {  57,   64,  39,     0             }, // Bishop
+    {  50,   40,  23,   -22,    0       }, // Rook
+    {  98,  105, -39,   141,  274,    0 }  // Queen
+  };
 
-  // Endgame evaluation and scaling functions accessed direcly and not through
-  // the function maps because correspond to more then one material hash key.
-  Endgame<KmmKm> EvaluateKmmKm[] = { Endgame<KmmKm>(WHITE), Endgame<KmmKm>(BLACK) };
+  // 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) };
@@ -61,38 +66,69 @@ namespace {
   // Helper templates used to detect a given material distribution
   template<Color Us> bool is_KXK(const Position& pos) {
     const Color Them = (Us == WHITE ? BLACK : WHITE);
-    return   pos.non_pawn_material(Them) == VALUE_ZERO
-          && pos.piece_count(Them, PAWN) == 0
-          && pos.non_pawn_material(Us)   >= RookValueMg;
+    return  !pos.count<PAWN>(Them)
+          && pos.non_pawn_material(Them) == VALUE_ZERO
+          && pos.non_pawn_material(Us) >= RookValueMg;
   }
 
   template<Color Us> bool is_KBPsKs(const Position& pos) {
-    return   pos.non_pawn_material(Us)   == BishopValueMg
-          && pos.piece_count(Us, BISHOP) == 1
-          && pos.piece_count(Us, PAWN)   >= 1;
+    return   pos.non_pawn_material(Us) == BishopValueMg
+          && pos.count<BISHOP>(Us) == 1
+          && pos.count<PAWN  >(Us) >= 1;
   }
 
   template<Color Us> bool is_KQKRPs(const Position& pos) {
     const Color Them = (Us == WHITE ? BLACK : WHITE);
-    return   pos.piece_count(Us, PAWN)    == 0
-          && pos.non_pawn_material(Us)    == QueenValueMg
-          && pos.piece_count(Us, QUEEN)   == 1
-          && pos.piece_count(Them, ROOK)  == 1
-          && pos.piece_count(Them, PAWN)  >= 1;
+    return  !pos.count<PAWN>(Us)
+          && pos.non_pawn_material(Us) == QueenValueMg
+          && pos.count<QUEEN>(Us)  == 1
+          && pos.count<ROOK>(Them) == 1
+          && pos.count<PAWN>(Them) >= 1;
+  }
+
+  /// imbalance() calculates the imbalance by comparing the piece count of each
+  /// piece type for both colors.
+
+  template<Color Us>
+  int imbalance(const int pieceCount[][PIECE_TYPE_NB]) {
+
+    const Color Them = (Us == WHITE ? BLACK : WHITE);
+
+    int pt1, pt2, pc, v;
+    int value = 0;
+
+    // Second-degree polynomial material imbalance by Tord Romstad
+    for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
+    {
+        pc = pieceCount[Us][pt1];
+        if (!pc)
+            continue;
+
+        v = LinearCoefficients[pt1];
+
+        for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; ++pt2)
+            v +=  QuadraticCoefficientsSameSide[pt1][pt2] * pieceCount[Us][pt2]
+                + QuadraticCoefficientsOppositeSide[pt1][pt2] * pieceCount[Them][pt2];
+
+        value += pc * v;
+    }
+
+    return value;
   }
 
 } // namespace
 
+namespace Material {
 
-/// MaterialTable::probe() takes a position object as input, looks up a MaterialEntry
+/// Material::probe() takes a position object as input, looks up a MaterialEntry
 /// object, and returns a pointer to it. If the material configuration is not
 /// already present in the table, it is computed and stored there, so we don't
 /// have to recompute everything when the same material configuration occurs again.
 
-MaterialEntry* MaterialTable::probe(const Position& pos) {
+Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
 
   Key key = pos.material_key();
-  MaterialEntry* e = entries[key];
+  Entry* e = entries[key];
 
   // If e->key matches the position's material hash key, it means that we
   // have analysed this material configuration before, and we can simply
@@ -100,14 +136,14 @@ MaterialEntry* MaterialTable::probe(const Position& pos) {
   if (e->key == key)
       return e;
 
-  memset(e, 0, sizeof(MaterialEntry));
+  std::memset(e, 0, sizeof(Entry));
   e->key = key;
   e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
-  e->gamePhase = MaterialTable::game_phase(pos);
+  e->gamePhase = game_phase(pos);
 
-  // Let's look if we have a specialized evaluation function for this
-  // particular material configuration. First we look for a fixed
-  // configuration one, then a generic one if previous search failed.
+  // 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 (endgames.probe(key, e->evaluationFunction))
       return e;
 
@@ -123,21 +159,6 @@ MaterialEntry* MaterialTable::probe(const Position& pos) {
       return e;
   }
 
-  if (!pos.pieces(PAWN) && !pos.pieces(ROOK) && !pos.pieces(QUEEN))
-  {
-      // Minor piece endgame with at least one minor piece per side and
-      // no pawns. Note that the case KmmK is already handled by KXK.
-      assert((pos.pieces(WHITE, KNIGHT) | pos.pieces(WHITE, BISHOP)));
-      assert((pos.pieces(BLACK, KNIGHT) | pos.pieces(BLACK, BISHOP)));
-
-      if (   pos.piece_count(WHITE, BISHOP) + pos.piece_count(WHITE, KNIGHT) <= 2
-          && pos.piece_count(BLACK, BISHOP) + pos.piece_count(BLACK, KNIGHT) <= 2)
-      {
-          e->evaluationFunction = &EvaluateKmmKm[pos.side_to_move()];
-          return e;
-      }
-  }
-
   // OK, we didn't find any special evaluation function for the current
   // material configuration. Is there a suitable scaling function?
   //
@@ -151,8 +172,8 @@ MaterialEntry* MaterialTable::probe(const Position& pos) {
       return e;
   }
 
-  // Generic scaling functions that refer to more then one material
-  // distribution. Should be probed after the specialized ones.
+  // Generic scaling functions that refer to more than one material
+  // distribution. They should be probed after the specialized ones.
   // Note that these ones don't return after setting the function.
   if (is_KBPsKs<WHITE>(pos))
       e->scalingFunction[WHITE] = &ScaleKBPsK[WHITE];
@@ -169,19 +190,19 @@ MaterialEntry* MaterialTable::probe(const Position& pos) {
   Value npm_w = pos.non_pawn_material(WHITE);
   Value npm_b = pos.non_pawn_material(BLACK);
 
-  if (npm_w + npm_b == VALUE_ZERO)
+  if (npm_w + npm_b == VALUE_ZERO && pos.pieces(PAWN))
   {
-      if (pos.piece_count(BLACK, PAWN) == 0)
+      if (!pos.count<PAWN>(BLACK))
       {
-          assert(pos.piece_count(WHITE, PAWN) >= 2);
+          assert(pos.count<PAWN>(WHITE) >= 2);
           e->scalingFunction[WHITE] = &ScaleKPsK[WHITE];
       }
-      else if (pos.piece_count(WHITE, PAWN) == 0)
+      else if (!pos.count<PAWN>(WHITE))
       {
-          assert(pos.piece_count(BLACK, PAWN) >= 2);
+          assert(pos.count<PAWN>(BLACK) >= 2);
           e->scalingFunction[BLACK] = &ScaleKPsK[BLACK];
       }
-      else if (pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1)
+      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.
@@ -190,83 +211,49 @@ MaterialEntry* MaterialTable::probe(const Position& pos) {
       }
   }
 
-  // No pawns makes it difficult to win, even with a material advantage
-  if (pos.piece_count(WHITE, PAWN) == 0 && npm_w - npm_b <= BishopValueMg)
-  {
-      e->factor[WHITE] = (uint8_t)
-      (npm_w == npm_b || npm_w < RookValueMg ? 0 : NoPawnsSF[std::min(pos.piece_count(WHITE, BISHOP), 2)]);
-  }
+  // No pawns makes it difficult to win, even with a material advantage. This
+  // catches some trivial draws like KK, KBK and KNK and gives a very 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 : 12);
 
-  if (pos.piece_count(BLACK, PAWN) == 0 && npm_b - npm_w <= BishopValueMg)
-  {
-      e->factor[BLACK] = (uint8_t)
-      (npm_w == npm_b || npm_b < RookValueMg ? 0 : NoPawnsSF[std::min(pos.piece_count(BLACK, BISHOP), 2)]);
-  }
+  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 : 12);
+
+  if (pos.count<PAWN>(WHITE) == 1 && npm_w - npm_b <= BishopValueMg)
+      e->factor[WHITE] = (uint8_t) SCALE_FACTOR_ONEPAWN;
+
+  if (pos.count<PAWN>(BLACK) == 1 && npm_b - npm_w <= BishopValueMg)
+      e->factor[BLACK] = (uint8_t) SCALE_FACTOR_ONEPAWN;
 
   // Compute the space weight
   if (npm_w + npm_b >= 2 * QueenValueMg + 4 * RookValueMg + 2 * KnightValueMg)
   {
-      int minorPieceCount =  pos.piece_count(WHITE, KNIGHT) + pos.piece_count(WHITE, BISHOP)
-                           + pos.piece_count(BLACK, KNIGHT) + pos.piece_count(BLACK, BISHOP);
+      int minorPieceCount =  pos.count<KNIGHT>(WHITE) + pos.count<BISHOP>(WHITE)
+                           + pos.count<KNIGHT>(BLACK) + pos.count<BISHOP>(BLACK);
 
-      e->spaceWeight = minorPieceCount * minorPieceCount;
+      e->spaceWeight = make_score(minorPieceCount * minorPieceCount, 0);
   }
 
   // Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder
-  // for the bishop pair "extended piece", this allow us to be more flexible
+  // for the bishop pair "extended piece", which allows us to be more flexible
   // in defining bishop pair bonuses.
-  const int pieceCount[2][8] = {
-  { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(WHITE, PAWN), pos.piece_count(WHITE, KNIGHT),
-    pos.piece_count(WHITE, BISHOP)    , pos.piece_count(WHITE, ROOK), pos.piece_count(WHITE, QUEEN) },
-  { pos.piece_count(BLACK, BISHOP) > 1, pos.piece_count(BLACK, PAWN), pos.piece_count(BLACK, KNIGHT),
-    pos.piece_count(BLACK, BISHOP)    , pos.piece_count(BLACK, ROOK), pos.piece_count(BLACK, QUEEN) } };
+  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->value = (int16_t)((imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16);
   return e;
 }
 
 
-/// MaterialTable::imbalance() calculates imbalance comparing piece count of each
-/// piece type for both colors.
-
-template<Color Us>
-int MaterialTable::imbalance(const int pieceCount[][8]) {
-
-  const Color Them = (Us == WHITE ? BLACK : WHITE);
-
-  int pt1, pt2, pc, v;
-  int value = 0;
-
-  // Redundancy of major pieces, formula based on Kaufman's paper
-  // "The Evaluation of Material Imbalances in Chess"
-  if (pieceCount[Us][ROOK] > 0)
-      value -=  RedundantRookPenalty * (pieceCount[Us][ROOK] - 1)
-              + RedundantQueenPenalty * pieceCount[Us][QUEEN];
-
-  // Second-degree polynomial material imbalance by Tord Romstad
-  for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
-  {
-      pc = pieceCount[Us][pt1];
-      if (!pc)
-          continue;
-
-      v = LinearCoefficients[pt1];
-
-      for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
-          v +=  QuadraticCoefficientsSameColor[pt1][pt2] * pieceCount[Us][pt2]
-              + QuadraticCoefficientsOppositeColor[pt1][pt2] * pieceCount[Them][pt2];
-
-      value += pc * v;
-  }
-  return value;
-}
-
-
-/// MaterialTable::game_phase() calculates the phase given the current
+/// Material::game_phase() calculates the phase given the current
 /// position. Because the phase is strictly a function of the material, it
 /// is stored in MaterialEntry.
 
-Phase MaterialTable::game_phase(const Position& pos) {
+Phase game_phase(const Position& pos) {
 
   Value npm = pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK);
 
@@ -274,3 +261,5 @@ Phase MaterialTable::game_phase(const Position& pos) {
         : npm <= EndgameLimit ? PHASE_ENDGAME
         : Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
 }
+
+} // namespace Material

src/material.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(MATERIAL_H_INCLUDED)
+#ifndef MATERIAL_H_INCLUDED
 #define MATERIAL_H_INCLUDED
 
 #include "endgame.h"
@@ -25,96 +25,51 @@
 #include "position.h"
 #include "types.h"
 
-const int MaterialTableSize = 8192;
+namespace Material {
 
-/// Game phase
-enum Phase {
-  PHASE_ENDGAME = 0,
-  PHASE_MIDGAME = 128
-};
-
-
-/// MaterialEntry is a class which contains various information about a
-/// material configuration. It contains a material balance evaluation,
-/// a function pointer to a special endgame evaluation function (which in
-/// most cases is NULL, meaning that the standard evaluation function will
-/// be used), and "scale factors" for black and white.
+/// Material::Entry contains various information about a material configuration.
+/// It contains a material balance evaluation, a function pointer to a special
+/// endgame evaluation function (which in most cases is NULL, 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.
 
-class MaterialEntry {
+struct Entry {
 
-  friend struct MaterialTable;
+  Score material_value() const { return make_score(value, value); }
+  Score space_weight() const { return spaceWeight; }
+  Phase game_phase() const { return gamePhase; }
+  bool specialized_eval_exists() const { return evaluationFunction != NULL; }
+  Value evaluate(const Position& pos) const { return (*evaluationFunction)(pos); }
 
-public:
-  Score material_value() const;
-  ScaleFactor scale_factor(const Position& pos, Color c) const;
-  int space_weight() const;
-  Phase game_phase() const;
-  bool specialized_eval_exists() const;
-  Value evaluate(const Position& pos) const;
+  // 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 need not be a constant: It can also be a function
+  // which should be applied to the position. For instance, in KBP vs K endgames,
+  // a scaling function for draws with rook pawns and wrong-colored bishops.
+
+  ScaleFactor scale_factor(const Position& pos, Color c) const {
+
+    return !scalingFunction[c] || (*scalingFunction[c])(pos) == SCALE_FACTOR_NONE
+          ? ScaleFactor(factor[c]) : (*scalingFunction[c])(pos);
+  }
 
-private:
   Key key;
   int16_t value;
-  uint8_t factor[2];
+  uint8_t factor[COLOR_NB];
   EndgameBase<Value>* evaluationFunction;
-  EndgameBase<ScaleFactor>* scalingFunction[2];
-  int spaceWeight;
+  EndgameBase<ScaleFactor>* scalingFunction[COLOR_NB];
+  Score spaceWeight;
   Phase gamePhase;
 };
 
+typedef HashTable<Entry, 8192> Table;
 
-/// The MaterialTable class represents a material hash table. The most important
-/// method is probe(), which returns a pointer to a MaterialEntry object.
+Entry* probe(const Position& pos, Table& entries, Endgames& endgames);
+Phase game_phase(const Position& pos);
 
-struct MaterialTable {
+} // namespace Material
 
-  MaterialEntry* probe(const Position& pos);
-  static Phase game_phase(const Position& pos);
-  template<Color Us> static int imbalance(const int pieceCount[][8]);
-
-  HashTable<MaterialEntry, MaterialTableSize> entries;
-  Endgames endgames;
-};
-
-
-/// MaterialEntry::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 need not
-/// to be a constant: It can also be a function which should be applied to
-/// the position. For instance, in KBP vs K endgames, a scaling function
-/// which checks for draws with rook pawns and wrong-colored bishops.
-
-inline ScaleFactor MaterialEntry::scale_factor(const Position& pos, Color c) const {
-
-  if (!scalingFunction[c])
-      return ScaleFactor(factor[c]);
-
-  ScaleFactor sf = (*scalingFunction[c])(pos);
-  return sf == SCALE_FACTOR_NONE ? ScaleFactor(factor[c]) : sf;
-}
-
-inline Value MaterialEntry::evaluate(const Position& pos) const {
-  return (*evaluationFunction)(pos);
-}
-
-inline Score MaterialEntry::material_value() const {
-  return make_score(value, value);
-}
-
-inline int MaterialEntry::space_weight() const {
-  return spaceWeight;
-}
-
-inline Phase MaterialEntry::game_phase() const {
-  return gamePhase;
-}
-
-inline bool MaterialEntry::specialized_eval_exists() const {
-  return evaluationFunction != NULL;
-}
-
-#endif // !defined(MATERIAL_H_INCLUDED)
+#endif // #ifndef MATERIAL_H_INCLUDED

src/misc.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,64 +24,48 @@
 #include "misc.h"
 #include "thread.h"
 
-#if defined(__hpux)
-#    include <sys/pstat.h>
-#endif
-
 using namespace std;
 
-/// Version number. If Version is left empty, then Tag plus current
-/// date (in the format YYMMDD) is used as a version number.
-
-static const string Version = "2.3.1";
-static const string Tag = "";
+/// Version number. If Version is left empty, then compile date in the format
+/// DD-MM-YY and show in engine_info.
+static const string Version = "5";
 
 
-/// engine_info() returns the full name of the current Stockfish version.
-/// This will be either "Stockfish YYMMDD" (where YYMMDD is the date when
-/// the program was compiled) or "Stockfish <version number>", depending
-/// on whether Version is empty.
+/// engine_info() returns the full name of the current Stockfish version. This
+/// will be either "Stockfish <Tag> DD-MM-YY" (where DD-MM-YY is the date when
+/// the program was compiled) or "Stockfish <Version>", depending on whether
+/// Version is empty.
 
 const string engine_info(bool to_uci) {
 
   const string months("Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec");
-  const string cpu64(Is64Bit ? " 64bit" : "");
-  const string popcnt(HasPopCnt ? " SSE4.2" : "");
-
   string month, day, year;
-  stringstream s, date(__DATE__); // From compiler, format is "Sep 21 2008"
+  stringstream ss, date(__DATE__); // From compiler, format is "Sep 21 2008"
 
-  s << "Stockfish " << Version;
+  ss << "Stockfish " << Version << setfill('0');
 
   if (Version.empty())
   {
       date >> month >> day >> year;
-
-      s << Tag << setfill('0') << " " << year.substr(2)
-        << setw(2) << (1 + months.find(month) / 4) << setw(2) << day;
+      ss << setw(2) << day << setw(2) << (1 + months.find(month) / 4) << year.substr(2);
   }
 
-  s << cpu64 << popcnt << (to_uci ? "\nid author ": " by ")
-    << "Tord Romstad, Marco Costalba and Joona Kiiski";
+  ss << (Is64Bit ? " 64" : "")
+     << (HasPext ? " BMI2" : (HasPopCnt ? " SSE4.2" : ""))
+     << (to_uci  ? "\nid author ": " by ")
+     << "Tord Romstad, Marco Costalba and Joona Kiiski";
 
-  return s.str();
-}
-
-
-/// Convert system time to milliseconds. That's all we need.
-
-Time::point Time::now() {
-  sys_time_t t; system_time(&t); return time_to_msec(t);
+  return ss.str();
 }
 
 
 /// Debug functions used mainly to collect run-time statistics
 
-static uint64_t hits[2], means[2];
+static int64_t hits[2], means[2];
 
-void dbg_hit_on(bool b) { hits[0]++; if (b) hits[1]++; }
+void dbg_hit_on(bool b) { ++hits[0]; if (b) ++hits[1]; }
 void dbg_hit_on_c(bool c, bool b) { if (c) dbg_hit_on(b); }
-void dbg_mean_of(int v) { means[0]++; means[1] += v; }
+void dbg_mean_of(int v) { ++means[0]; means[1] += v; }
 
 void dbg_print() {
 
@@ -91,14 +75,14 @@ void dbg_print() {
 
   if (means[0])
       cerr << "Total " << means[0] << " Mean "
-           << (float)means[1] / means[0] << endl;
+           << (double)means[1] / means[0] << endl;
 }
 
 
 /// Our fancy logging facility. The trick here is to replace cin.rdbuf() and
 /// cout.rdbuf() with two Tie objects that tie cin and cout to a file stream. We
-/// can toggle the logging of std::cout and std:cin at runtime while preserving
-/// usual i/o functionality and without changing a single line of code!
+/// can toggle the logging of std::cout and std:cin at runtime whilst preserving
+/// usual i/o functionality, all without changing a single line of code!
 /// Idea from http://groups.google.com/group/comp.lang.c++/msg/1d941c0f26ea0d81
 
 struct Tie: public streambuf { // MSVC requires splitted streambuf for cin and cout
@@ -153,17 +137,17 @@ public:
 };
 
 
-/// Used to serialize access to std::cout to avoid multiple threads to write at
+/// Used to serialize access to std::cout to avoid multiple threads writing at
 /// the same time.
 
 std::ostream& operator<<(std::ostream& os, SyncCout sc) {
 
   static Mutex m;
 
-  if (sc == io_lock)
+  if (sc == IO_LOCK)
       m.lock();
 
-  if (sc == io_unlock)
+  if (sc == IO_UNLOCK)
       m.unlock();
 
   return os;
@@ -174,37 +158,12 @@ std::ostream& operator<<(std::ostream& os, SyncCout sc) {
 void start_logger(bool b) { Logger::start(b); }
 
 
-/// cpu_count() tries to detect the number of CPU cores
-
-int cpu_count() {
-
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO s;
-  GetSystemInfo(&s);
-  return s.dwNumberOfProcessors;
-#else
-
-#  if defined(_SC_NPROCESSORS_ONLN)
-  return sysconf(_SC_NPROCESSORS_ONLN);
-#  elif defined(__hpux)
-  struct pst_dynamic psd;
-  if (pstat_getdynamic(&psd, sizeof(psd), (size_t)1, 0) == -1)
-      return 1;
-  return psd.psd_proc_cnt;
-#  else
-  return 1;
-#  endif
-
-#endif
-}
-
-
-/// timed_wait() waits for msec milliseconds. It is mainly an helper to wrap
-/// conversion from milliseconds to struct timespec, as used by pthreads.
+/// timed_wait() waits for msec milliseconds. It is mainly a helper to wrap
+/// the conversion from milliseconds to struct timespec, as used by pthreads.
 
 void timed_wait(WaitCondition& sleepCond, Lock& sleepLock, int msec) {
 
-#if defined(_WIN32) || defined(_WIN64)
+#ifdef _WIN32
   int tm = msec;
 #else
   timespec ts, *tm = &ts;
@@ -218,27 +177,28 @@ void timed_wait(WaitCondition& sleepCond, Lock& sleepLock, int msec) {
 }
 
 
-/// prefetch() preloads the given address in L1/L2 cache. This is a non
-/// blocking function and do not stalls the CPU waiting for data to be
-/// loaded from memory, that can be quite slow.
-#if defined(NO_PREFETCH)
+/// prefetch() 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.
+#ifdef NO_PREFETCH
 
 void prefetch(char*) {}
 
 #else
 
-#   include <xmmintrin.h>
-
 void prefetch(char* addr) {
 
-#  if defined(__INTEL_COMPILER) || defined(__ICL)
-   // This hack prevents prefetches to be optimized away by
-   // Intel compiler. Both MSVC and gcc seems not affected.
+#  if defined(__INTEL_COMPILER)
+   // This hack prevents prefetches from being optimized away by
+   // Intel compiler. Both MSVC and gcc seem not be affected by this.
    __asm__ ("");
 #  endif
 
-  _mm_prefetch(addr, _MM_HINT_T2);
-  _mm_prefetch(addr+64, _MM_HINT_T2); // 64 bytes ahead
+#  if defined(__INTEL_COMPILER) || defined(_MSC_VER)
+  _mm_prefetch(addr, _MM_HINT_T0);
+#  else
+  __builtin_prefetch(addr);
+#  endif
 }
 
 #endif

src/misc.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(MISC_H_INCLUDED)
+#ifndef MISC_H_INCLUDED
 #define MISC_H_INCLUDED
 
 #include <fstream>
@@ -27,7 +27,6 @@
 #include "types.h"
 
 extern const std::string engine_info(bool to_uci = false);
-extern int cpu_count();
 extern void timed_wait(WaitCondition&, Lock&, int);
 extern void prefetch(char* addr);
 extern void start_logger(bool b);
@@ -46,24 +45,24 @@ struct Log : public std::ofstream {
 
 namespace Time {
   typedef int64_t point;
-  point now();
+  inline point now() { return system_time_to_msec(); }
 }
 
 
 template<class Entry, int Size>
 struct HashTable {
-  HashTable() : e(Size, Entry()) {}
-  Entry* operator[](Key k) { return &e[(uint32_t)k & (Size - 1)]; }
+  HashTable() : table(Size, Entry()) {}
+  Entry* operator[](Key k) { return &table[(uint32_t)k & (Size - 1)]; }
 
 private:
-  std::vector<Entry> e;
+  std::vector<Entry> table;
 };
 
 
-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
+#define sync_cout std::cout << IO_LOCK
+#define sync_endl std::endl << IO_UNLOCK
 
-#endif // !defined(MISC_H_INCLUDED)
+#endif // #ifndef MISC_H_INCLUDED

src/movegen.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,88 +22,73 @@
 #include "movegen.h"
 #include "position.h"
 
-/// Simple macro to wrap a very common while loop, no facny, no flexibility,
-/// hardcoded names 'mlist' and 'from'.
-#define SERIALIZE(b) while (b) (*mlist++).move = make_move(from, pop_lsb(&b))
-
-/// Version used for pawns, where the 'from' square is given as a delta from the 'to' square
-#define SERIALIZE_PAWNS(b, d) while (b) { Square to = pop_lsb(&b); \
-                                         (*mlist++).move = make_move(to - (d), to); }
 namespace {
 
-  template<CastlingSide Side, bool Checks, bool Chess960>
-  MoveStack* generate_castle(const Position& pos, MoveStack* mlist, Color us) {
+  template<CastlingRight Cr, bool Checks, bool Chess960>
+  ExtMove* generate_castling(const Position& pos, ExtMove* mlist, Color us, const CheckInfo* ci) {
 
-    if (pos.castle_impeded(us, Side) || !pos.can_castle(make_castle_right(us, Side)))
+    static const bool KingSide = (Cr == WHITE_OO || Cr == BLACK_OO);
+
+    if (pos.castling_impeded(Cr) || !pos.can_castle(Cr))
         return mlist;
 
     // After castling, the rook and king final positions are the same in Chess960
     // as they would be in standard chess.
     Square kfrom = pos.king_square(us);
-    Square rfrom = pos.castle_rook_square(us, Side);
-    Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
+    Square rfrom = pos.castling_rook_square(Cr);
+    Square kto = relative_square(us, KingSide ? SQ_G1 : SQ_C1);
     Bitboard enemies = pos.pieces(~us);
 
-    assert(!pos.in_check());
+    assert(!pos.checkers());
 
-    const int K = Chess960 ? kto > kfrom ? -1 : 1
-                           : Side == KING_SIDE ? -1 : 1;
+    const Square K = Chess960 ? kto > kfrom ? DELTA_W : DELTA_E
+                              : KingSide    ? DELTA_W : DELTA_E;
 
-    for (Square s = kto; s != kfrom; s += (Square)K)
+    for (Square s = kto; s != kfrom; s += K)
         if (pos.attackers_to(s) & enemies)
             return mlist;
 
     // Because we generate only legal castling moves we need to verify that
     // when moving the castling rook we do not discover some hidden checker.
     // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
-    if (Chess960 && (pos.attackers_to(kto, pos.pieces() ^ rfrom) & enemies))
+    if (Chess960 && (attacks_bb<ROOK>(kto, pos.pieces() ^ rfrom) & pos.pieces(~us, ROOK, QUEEN)))
         return mlist;
 
-    (*mlist++).move = make<CASTLE>(kfrom, rfrom);
+    Move m = make<CASTLING>(kfrom, rfrom);
 
-    if (Checks && !pos.move_gives_check((mlist - 1)->move, CheckInfo(pos)))
-        mlist--;
+    if (Checks && !pos.gives_check(m, *ci))
+        return mlist;
+
+    (mlist++)->move = m;
 
     return mlist;
   }
 
 
-  template<Square Delta>
-  inline Bitboard move_pawns(Bitboard p) {
-
-    return  Delta == DELTA_N  ?  p << 8
-          : Delta == DELTA_S  ?  p >> 8
-          : Delta == DELTA_NE ? (p & ~FileHBB) << 9
-          : Delta == DELTA_SE ? (p & ~FileHBB) >> 7
-          : Delta == DELTA_NW ? (p & ~FileABB) << 7
-          : Delta == DELTA_SW ? (p & ~FileABB) >> 9 : 0;
-  }
-
-
   template<GenType Type, Square Delta>
-  inline MoveStack* generate_promotions(MoveStack* mlist, Bitboard pawnsOn7,
-                                        Bitboard target, const CheckInfo* ci) {
+  inline ExtMove* generate_promotions(ExtMove* mlist, Bitboard pawnsOn7,
+                                      Bitboard target, const CheckInfo* ci) {
 
-    Bitboard b = move_pawns<Delta>(pawnsOn7) & target;
+    Bitboard b = shift_bb<Delta>(pawnsOn7) & target;
 
     while (b)
     {
         Square to = pop_lsb(&b);
 
         if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
-            (*mlist++).move = make<PROMOTION>(to - Delta, to, QUEEN);
+            (mlist++)->move = make<PROMOTION>(to - Delta, to, QUEEN);
 
         if (Type == QUIETS || Type == EVASIONS || Type == NON_EVASIONS)
         {
-            (*mlist++).move = make<PROMOTION>(to - Delta, to, ROOK);
-            (*mlist++).move = make<PROMOTION>(to - Delta, to, BISHOP);
-            (*mlist++).move = make<PROMOTION>(to - Delta, to, KNIGHT);
+            (mlist++)->move = make<PROMOTION>(to - Delta, to, ROOK);
+            (mlist++)->move = make<PROMOTION>(to - Delta, to, BISHOP);
+            (mlist++)->move = make<PROMOTION>(to - Delta, to, KNIGHT);
         }
 
-        // Knight-promotion is the only one that can give a direct check not
-        // already included in the queen-promotion.
+        // Knight promotion is the only promotion that can give a direct check
+        // that's not already included in the queen promotion.
         if (Type == QUIET_CHECKS && (StepAttacksBB[W_KNIGHT][to] & ci->ksq))
-            (*mlist++).move = make<PROMOTION>(to - Delta, to, KNIGHT);
+            (mlist++)->move = make<PROMOTION>(to - Delta, to, KNIGHT);
         else
             (void)ci; // Silence a warning under MSVC
     }
@@ -113,8 +98,8 @@ namespace {
 
 
   template<Color Us, GenType Type>
-  MoveStack* generate_pawn_moves(const Position& pos, MoveStack* mlist,
-                                 Bitboard target, const CheckInfo* ci) {
+  ExtMove* generate_pawn_moves(const Position& pos, ExtMove* mlist,
+                               Bitboard target, const CheckInfo* ci) {
 
     // Compute our parametrized parameters at compile time, named according to
     // the point of view of white side.
@@ -122,9 +107,9 @@ namespace {
     const Bitboard TRank8BB = (Us == WHITE ? Rank8BB  : Rank1BB);
     const Bitboard TRank7BB = (Us == WHITE ? Rank7BB  : Rank2BB);
     const Bitboard TRank3BB = (Us == WHITE ? Rank3BB  : Rank6BB);
-    const Square   UP       = (Us == WHITE ? DELTA_N  : DELTA_S);
-    const Square   RIGHT    = (Us == WHITE ? DELTA_NE : DELTA_SW);
-    const Square   LEFT     = (Us == WHITE ? DELTA_NW : DELTA_SE);
+    const Square   Up       = (Us == WHITE ? DELTA_N  : DELTA_S);
+    const Square   Right    = (Us == WHITE ? DELTA_NE : DELTA_SW);
+    const Square   Left     = (Us == WHITE ? DELTA_NW : DELTA_SE);
 
     Bitboard b1, b2, dc1, dc2, emptySquares;
 
@@ -139,8 +124,8 @@ namespace {
     {
         emptySquares = (Type == QUIETS || Type == QUIET_CHECKS ? target : ~pos.pieces());
 
-        b1 = move_pawns<UP>(pawnsNotOn7)   & emptySquares;
-        b2 = move_pawns<UP>(b1 & TRank3BB) & emptySquares;
+        b1 = shift_bb<Up>(pawnsNotOn7)   & emptySquares;
+        b2 = shift_bb<Up>(b1 & TRank3BB) & emptySquares;
 
         if (Type == EVASIONS) // Consider only blocking squares
         {
@@ -156,19 +141,28 @@ namespace {
             // Add pawn pushes which give discovered check. This is possible only
             // if the pawn is not on the same file as the enemy king, because we
             // don't generate captures. Note that a possible discovery check
-            // promotion has been already generated among captures.
+            // promotion has been already generated amongst the captures.
             if (pawnsNotOn7 & ci->dcCandidates)
             {
-                dc1 = move_pawns<UP>(pawnsNotOn7 & ci->dcCandidates) & emptySquares & ~file_bb(ci->ksq);
-                dc2 = move_pawns<UP>(dc1 & TRank3BB) & emptySquares;
+                dc1 = shift_bb<Up>(pawnsNotOn7 & ci->dcCandidates) & emptySquares & ~file_bb(ci->ksq);
+                dc2 = shift_bb<Up>(dc1 & TRank3BB) & emptySquares;
 
                 b1 |= dc1;
                 b2 |= dc2;
             }
         }
 
-        SERIALIZE_PAWNS(b1, UP);
-        SERIALIZE_PAWNS(b2, UP + UP);
+        while (b1)
+        {
+            Square to = pop_lsb(&b1);
+            (mlist++)->move = make_move(to - Up, to);
+        }
+
+        while (b2)
+        {
+            Square to = pop_lsb(&b2);
+            (mlist++)->move = make_move(to - Up - Up, to);
+        }
     }
 
     // Promotions and underpromotions
@@ -180,19 +174,28 @@ namespace {
         if (Type == EVASIONS)
             emptySquares &= target;
 
-        mlist = generate_promotions<Type, RIGHT>(mlist, pawnsOn7, enemies, ci);
-        mlist = generate_promotions<Type, LEFT>(mlist, pawnsOn7, enemies, ci);
-        mlist = generate_promotions<Type, UP>(mlist, pawnsOn7, emptySquares, ci);
+        mlist = generate_promotions<Type, Right>(mlist, pawnsOn7, enemies, ci);
+        mlist = generate_promotions<Type, Left >(mlist, pawnsOn7, enemies, ci);
+        mlist = generate_promotions<Type, Up>(mlist, pawnsOn7, emptySquares, ci);
     }
 
     // Standard and en-passant captures
     if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
     {
-        b1 = move_pawns<RIGHT>(pawnsNotOn7) & enemies;
-        b2 = move_pawns<LEFT >(pawnsNotOn7) & enemies;
+        b1 = shift_bb<Right>(pawnsNotOn7) & enemies;
+        b2 = shift_bb<Left >(pawnsNotOn7) & enemies;
 
-        SERIALIZE_PAWNS(b1, RIGHT);
-        SERIALIZE_PAWNS(b2, LEFT);
+        while (b1)
+        {
+            Square to = pop_lsb(&b1);
+            (mlist++)->move = make_move(to - Right, to);
+        }
+
+        while (b2)
+        {
+            Square to = pop_lsb(&b2);
+            (mlist++)->move = make_move(to - Left, to);
+        }
 
         if (pos.ep_square() != SQ_NONE)
         {
@@ -201,7 +204,7 @@ namespace {
             // An en passant capture can be an evasion only if the checking piece
             // is the double pushed pawn and so is in the target. Otherwise this
             // is a discovery check and we are forced to do otherwise.
-            if (Type == EVASIONS && !(target & (pos.ep_square() - UP)))
+            if (Type == EVASIONS && !(target & (pos.ep_square() - Up)))
                 return mlist;
 
             b1 = pawnsNotOn7 & pos.attacks_from<PAWN>(pos.ep_square(), Them);
@@ -209,7 +212,7 @@ namespace {
             assert(b1);
 
             while (b1)
-                (*mlist++).move = make<ENPASSANT>(pop_lsb(&b1), pos.ep_square());
+                (mlist++)->move = make<ENPASSANT>(pop_lsb(&b1), pos.ep_square());
         }
     }
 
@@ -218,12 +221,12 @@ namespace {
 
 
   template<PieceType Pt, bool Checks> FORCE_INLINE
-  MoveStack* generate_moves(const Position& pos, MoveStack* mlist, Color us,
-                            Bitboard target, const CheckInfo* ci) {
+  ExtMove* generate_moves(const Position& pos, ExtMove* mlist, Color us,
+                          Bitboard target, const CheckInfo* ci) {
 
     assert(Pt != KING && Pt != PAWN);
 
-    const Square* pl = pos.piece_list(us, Pt);
+    const Square* pl = pos.list<Pt>(us);
 
     for (Square from = *pl; from != SQ_NONE; from = *++pl)
     {
@@ -233,7 +236,7 @@ namespace {
                 && !(PseudoAttacks[Pt][from] & target & ci->checkSq[Pt]))
                 continue;
 
-            if (ci->dcCandidates && (ci->dcCandidates & from))
+            if (unlikely(ci->dcCandidates) && (ci->dcCandidates & from))
                 continue;
         }
 
@@ -242,48 +245,45 @@ namespace {
         if (Checks)
             b &= ci->checkSq[Pt];
 
-        SERIALIZE(b);
+        while (b)
+            (mlist++)->move = make_move(from, pop_lsb(&b));
     }
 
     return mlist;
   }
 
 
-  FORCE_INLINE MoveStack* generate_king_moves(const Position& pos, MoveStack* mlist,
-                                              Color us, Bitboard target) {
-    Square from = pos.king_square(us);
-    Bitboard b = pos.attacks_from<KING>(from) & target;
-    SERIALIZE(b);
-    return mlist;
-  }
+  template<Color Us, GenType Type> FORCE_INLINE
+  ExtMove* generate_all(const Position& pos, ExtMove* mlist, Bitboard target,
+                        const CheckInfo* ci = NULL) {
 
+    const bool Checks = Type == QUIET_CHECKS;
 
-  template<GenType Type> FORCE_INLINE
-  MoveStack* generate_all_moves(const Position& pos, MoveStack* mlist, Color us,
-                                Bitboard target, const CheckInfo* ci = NULL) {
-
-    mlist = (us == WHITE ? generate_pawn_moves<WHITE, Type>(pos, mlist, target, ci)
-                         : generate_pawn_moves<BLACK, Type>(pos, mlist, target, ci));
-
-    mlist = generate_moves<KNIGHT, Type == QUIET_CHECKS>(pos, mlist, us, target, ci);
-    mlist = generate_moves<BISHOP, Type == QUIET_CHECKS>(pos, mlist, us, target, ci);
-    mlist = generate_moves<ROOK,   Type == QUIET_CHECKS>(pos, mlist, us, target, ci);
-    mlist = generate_moves<QUEEN,  Type == QUIET_CHECKS>(pos, mlist, us, target, ci);
+    mlist = generate_pawn_moves<Us, Type>(pos, mlist, target, ci);
+    mlist = generate_moves<KNIGHT, Checks>(pos, mlist, Us, target, ci);
+    mlist = generate_moves<BISHOP, Checks>(pos, mlist, Us, target, ci);
+    mlist = generate_moves<  ROOK, Checks>(pos, mlist, Us, target, ci);
+    mlist = generate_moves< QUEEN, Checks>(pos, mlist, Us, target, ci);
 
     if (Type != QUIET_CHECKS && Type != EVASIONS)
-        mlist = generate_king_moves(pos, mlist, us, target);
+    {
+        Square ksq = pos.king_square(Us);
+        Bitboard b = pos.attacks_from<KING>(ksq) & target;
+        while (b)
+            (mlist++)->move = make_move(ksq, pop_lsb(&b));
+    }
 
-    if (Type != CAPTURES && Type != EVASIONS && pos.can_castle(us))
+    if (Type != CAPTURES && Type != EVASIONS && pos.can_castle(Us))
     {
         if (pos.is_chess960())
         {
-            mlist = generate_castle<KING_SIDE,  Type == QUIET_CHECKS, true>(pos, mlist, us);
-            mlist = generate_castle<QUEEN_SIDE, Type == QUIET_CHECKS, true>(pos, mlist, us);
+            mlist = generate_castling<MakeCastling<Us,  KING_SIDE>::right, Checks, true>(pos, mlist, Us, ci);
+            mlist = generate_castling<MakeCastling<Us, QUEEN_SIDE>::right, Checks, true>(pos, mlist, Us, ci);
         }
         else
         {
-            mlist = generate_castle<KING_SIDE,  Type == QUIET_CHECKS, false>(pos, mlist, us);
-            mlist = generate_castle<QUEEN_SIDE, Type == QUIET_CHECKS, false>(pos, mlist, us);
+            mlist = generate_castling<MakeCastling<Us,  KING_SIDE>::right, Checks, false>(pos, mlist, Us, ci);
+            mlist = generate_castling<MakeCastling<Us, QUEEN_SIDE>::right, Checks, false>(pos, mlist, Us, ci);
         }
     }
 
@@ -304,38 +304,33 @@ namespace {
 /// non-captures. Returns a pointer to the end of the move list.
 
 template<GenType Type>
-MoveStack* generate(const Position& pos, MoveStack* mlist) {
+ExtMove* generate(const Position& pos, ExtMove* mlist) {
 
   assert(Type == CAPTURES || Type == QUIETS || Type == NON_EVASIONS);
-  assert(!pos.in_check());
+  assert(!pos.checkers());
 
   Color us = pos.side_to_move();
-  Bitboard target;
 
-  if (Type == CAPTURES)
-      target = pos.pieces(~us);
+  Bitboard target = Type == CAPTURES     ?  pos.pieces(~us)
+                  : Type == QUIETS       ? ~pos.pieces()
+                  : Type == NON_EVASIONS ? ~pos.pieces(us) : 0;
 
-  else if (Type == QUIETS)
-      target = ~pos.pieces();
-
-  else if (Type == NON_EVASIONS)
-      target = ~pos.pieces(us);
-
-  return generate_all_moves<Type>(pos, mlist, us, target);
+  return us == WHITE ? generate_all<WHITE, Type>(pos, mlist, target)
+                     : generate_all<BLACK, Type>(pos, mlist, target);
 }
 
 // Explicit template instantiations
-template MoveStack* generate<CAPTURES>(const Position&, MoveStack*);
-template MoveStack* generate<QUIETS>(const Position&, MoveStack*);
-template MoveStack* generate<NON_EVASIONS>(const Position&, MoveStack*);
+template ExtMove* generate<CAPTURES>(const Position&, ExtMove*);
+template ExtMove* generate<QUIETS>(const Position&, ExtMove*);
+template ExtMove* generate<NON_EVASIONS>(const Position&, ExtMove*);
 
 
 /// generate<QUIET_CHECKS> generates all pseudo-legal non-captures and knight
 /// underpromotions that give check. Returns a pointer to the end of the move list.
 template<>
-MoveStack* generate<QUIET_CHECKS>(const Position& pos, MoveStack* mlist) {
+ExtMove* generate<QUIET_CHECKS>(const Position& pos, ExtMove* mlist) {
 
-  assert(!pos.in_check());
+  assert(!pos.checkers());
 
   Color us = pos.side_to_move();
   CheckInfo ci(pos);
@@ -347,99 +342,77 @@ MoveStack* generate<QUIET_CHECKS>(const Position& pos, MoveStack* mlist) {
      PieceType pt = type_of(pos.piece_on(from));
 
      if (pt == PAWN)
-         continue; // Will be generated togheter with direct checks
+         continue; // Will be generated together with direct checks
 
      Bitboard b = pos.attacks_from(Piece(pt), from) & ~pos.pieces();
 
      if (pt == KING)
          b &= ~PseudoAttacks[QUEEN][ci.ksq];
 
-     SERIALIZE(b);
+     while (b)
+         (mlist++)->move = make_move(from, pop_lsb(&b));
   }
 
-  return generate_all_moves<QUIET_CHECKS>(pos, mlist, us, ~pos.pieces(), &ci);
+  return us == WHITE ? generate_all<WHITE, QUIET_CHECKS>(pos, mlist, ~pos.pieces(), &ci)
+                     : generate_all<BLACK, QUIET_CHECKS>(pos, mlist, ~pos.pieces(), &ci);
 }
 
 
 /// generate<EVASIONS> generates all pseudo-legal check evasions when the side
 /// to move is in check. Returns a pointer to the end of the move list.
 template<>
-MoveStack* generate<EVASIONS>(const Position& pos, MoveStack* mlist) {
-
-  assert(pos.in_check());
-
-  Square from, checksq;
-  int checkersCnt = 0;
-  Color us = pos.side_to_move();
-  Square ksq = pos.king_square(us);
-  Bitboard sliderAttacks = 0;
-  Bitboard b = pos.checkers();
+ExtMove* generate<EVASIONS>(const Position& pos, ExtMove* mlist) {
 
   assert(pos.checkers());
 
-  // Find squares attacked by slider checkers, we will remove them from the king
-  // evasions so to skip known illegal moves avoiding useless legality check later.
-  do
+  Color us = pos.side_to_move();
+  Square ksq = pos.king_square(us);
+  Bitboard sliderAttacks = 0;
+  Bitboard sliders = pos.checkers() & ~pos.pieces(KNIGHT, PAWN);
+
+  // Find all the squares attacked by slider checkers. We will remove them from
+  // the king evasions in order to skip known illegal moves, which avoids any
+  // useless legality checks later on.
+  while (sliders)
   {
-      checkersCnt++;
-      checksq = pop_lsb(&b);
-
-      assert(color_of(pos.piece_on(checksq)) == ~us);
-
-      switch (type_of(pos.piece_on(checksq)))
-      {
-      case BISHOP: sliderAttacks |= PseudoAttacks[BISHOP][checksq]; break;
-      case ROOK:   sliderAttacks |= PseudoAttacks[ROOK][checksq];   break;
-      case QUEEN:
-          // If queen and king are far or not on a diagonal line we can safely
-          // remove all the squares attacked in the other direction becuase are
-          // not reachable by the king anyway.
-          if (between_bb(ksq, checksq) || !(PseudoAttacks[BISHOP][checksq] & ksq))
-              sliderAttacks |= PseudoAttacks[QUEEN][checksq];
-
-          // Otherwise we need to use real rook attacks to check if king is safe
-          // to move in the other direction. For example: king in B2, queen in A1
-          // a knight in B1, and we can safely move to C1.
-          else
-              sliderAttacks |= PseudoAttacks[BISHOP][checksq] | pos.attacks_from<ROOK>(checksq);
-
-      default:
-          break;
-      }
-  } while (b);
+      Square checksq = pop_lsb(&sliders);
+      sliderAttacks |= LineBB[checksq][ksq] ^ checksq;
+  }
 
   // Generate evasions for king, capture and non capture moves
-  b = pos.attacks_from<KING>(ksq) & ~pos.pieces(us) & ~sliderAttacks;
-  from = ksq;
-  SERIALIZE(b);
+  Bitboard b = pos.attacks_from<KING>(ksq) & ~pos.pieces(us) & ~sliderAttacks;
+  while (b)
+      (mlist++)->move = make_move(ksq, pop_lsb(&b));
 
-  if (checkersCnt > 1)
+  if (more_than_one(pos.checkers()))
       return mlist; // Double check, only a king move can save the day
 
   // Generate blocking evasions or captures of the checking piece
-  Bitboard target = between_bb(checksq, ksq) | pos.checkers();
+  Square checksq = lsb(pos.checkers());
+  Bitboard target = between_bb(checksq, ksq) | checksq;
 
-  return generate_all_moves<EVASIONS>(pos, mlist, us, target);
+  return us == WHITE ? generate_all<WHITE, EVASIONS>(pos, mlist, target)
+                     : generate_all<BLACK, EVASIONS>(pos, mlist, target);
 }
 
 
 /// generate<LEGAL> generates all the legal moves in the given position
 
 template<>
-MoveStack* generate<LEGAL>(const Position& pos, MoveStack* mlist) {
+ExtMove* generate<LEGAL>(const Position& pos, ExtMove* mlist) {
 
-  MoveStack *end, *cur = mlist;
-  Bitboard pinned = pos.pinned_pieces();
+  ExtMove *end, *cur = mlist;
+  Bitboard pinned = pos.pinned_pieces(pos.side_to_move());
   Square ksq = pos.king_square(pos.side_to_move());
 
-  end = pos.in_check() ? generate<EVASIONS>(pos, mlist)
+  end = pos.checkers() ? generate<EVASIONS>(pos, mlist)
                        : generate<NON_EVASIONS>(pos, mlist);
   while (cur != end)
       if (   (pinned || from_sq(cur->move) == ksq || type_of(cur->move) == ENPASSANT)
-          && !pos.pl_move_is_legal(cur->move, pinned))
+          && !pos.legal(cur->move, pinned))
           cur->move = (--end)->move;
       else
-          cur++;
+          ++cur;
 
   return end;
 }

src/movegen.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(MOVEGEN_H_INCLUDED)
+#ifndef MOVEGEN_H_INCLUDED
 #define MOVEGEN_H_INCLUDED
 
 #include "types.h"
@@ -34,22 +34,25 @@ enum GenType {
 class Position;
 
 template<GenType>
-MoveStack* generate(const Position& pos, MoveStack* mlist);
+ExtMove* generate(const Position& pos, ExtMove* mlist);
 
-/// The MoveList struct is a simple wrapper around generate(), sometimes comes
-/// handy to use this class instead of the low level generate() function.
+/// 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.
 template<GenType T>
 struct MoveList {
 
-  explicit MoveList(const Position& pos) : cur(mlist), last(generate<T>(pos, mlist)) {}
-  void operator++() { cur++; }
-  bool end() const { return cur == last; }
-  Move move() const { return cur->move; }
+  explicit MoveList(const Position& pos) : cur(mlist), last(generate<T>(pos, mlist)) { last->move = MOVE_NONE; }
+  void operator++() { ++cur; }
+  Move operator*() const { return cur->move; }
   size_t size() const { return last - mlist; }
+  bool contains(Move m) const {
+    for (const ExtMove* it(mlist); it != last; ++it) if (it->move == m) return true;
+    return false;
+  }
 
 private:
-  MoveStack mlist[MAX_MOVES];
-  MoveStack *cur, *last;
+  ExtMove mlist[MAX_MOVES];
+  ExtMove *cur, *last;
 };
 
-#endif // !defined(MOVEGEN_H_INCLUDED)
+#endif // #ifndef MOVEGEN_H_INCLUDED

src/movepick.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,16 +18,14 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <algorithm>
 #include <cassert>
 
-#include "movegen.h"
 #include "movepick.h"
 #include "thread.h"
 
 namespace {
 
-  enum Sequencer {
+  enum Stages {
     MAIN_SEARCH, CAPTURES_S1, KILLERS_S1, QUIETS_1_S1, QUIETS_2_S1, BAD_CAPTURES_S1,
     EVASION,     EVASIONS_S2,
     QSEARCH_0,   CAPTURES_S3, QUIET_CHECKS_S3,
@@ -37,14 +35,28 @@ namespace {
     STOP
   };
 
-  // Unary predicate used by std::partition to split positive scores from remaining
-  // ones so to sort separately the two sets, and with the second sort delayed.
-  inline bool has_positive_score(const MoveStack& ms) { return ms.score > 0; }
+  // Our insertion sort, which is guaranteed (and also needed) to be stable
+  void insertion_sort(ExtMove* begin, ExtMove* end)
+  {
+    ExtMove tmp, *p, *q;
 
-  // Picks and moves to the front the best move in the range [begin, end),
-  // it is faster than sorting all the moves in advance when moves are few, as
-  // normally are the possible captures.
-  inline MoveStack* pick_best(MoveStack* begin, MoveStack* end)
+    for (p = begin + 1; p < end; ++p)
+    {
+        tmp = *p;
+        for (q = p; q != begin && *(q-1) < tmp; --q)
+            *q = *(q-1);
+        *q = tmp;
+    }
+  }
+
+  // Unary predicate used by std::partition to split positive values from remaining
+  // ones so as to sort the two sets separately, with the second sort delayed.
+  inline bool has_positive_value(const ExtMove& ms) { return ms.value > 0; }
+
+  // Picks the best move in the range (begin, end) and moves it to the front.
+  // It's faster than sorting all the moves in advance when there are few
+  // moves e.g. possible captures.
+  inline ExtMove* pick_best(ExtMove* begin, ExtMove* end)
   {
       std::swap(*begin, *std::max_element(begin, end));
       return begin;
@@ -53,100 +65,87 @@ namespace {
 
 
 /// Constructors of the MovePicker class. As arguments we pass information
-/// to help it to return the presumably good moves first, to decide which
+/// 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 about how important good
-/// move ordering is at the current node.
+/// search captures, promotions and some checks) and how important good move
+/// ordering is at the current node.
 
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
-                       Search::Stack* s, Value beta) : pos(p), H(h), depth(d) {
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h,
+                       Move* cm, Move* fm, Search::Stack* s) : pos(p), history(h), depth(d) {
 
   assert(d > DEPTH_ZERO);
 
-  captureThreshold = 0;
   cur = end = moves;
   endBadCaptures = moves + MAX_MOVES - 1;
+  countermoves = cm;
+  followupmoves = fm;
   ss = s;
 
-  if (p.in_check())
-      phase = EVASION;
+  if (pos.checkers())
+      stage = EVASION;
 
   else
-  {
-      phase = MAIN_SEARCH;
+      stage = MAIN_SEARCH;
 
-      killers[0].move = ss->killers[0];
-      killers[1].move = ss->killers[1];
-
-      // Consider sligtly negative captures as good if at low depth and far from beta
-      if (ss && ss->eval < beta - PawnValueMg && d < 3 * ONE_PLY)
-          captureThreshold = -PawnValueMg;
-
-      // Consider negative captures as good if still enough to reach beta
-      else if (ss && ss->eval > beta)
-          captureThreshold = beta - ss->eval;
-  }
-
-  ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE);
+  ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE);
   end += (ttMove != MOVE_NONE);
 }
 
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
-                       Square sq) : pos(p), H(h), cur(moves), end(moves) {
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h,
+                       Square s) : pos(p), history(h), cur(moves), end(moves) {
 
   assert(d <= DEPTH_ZERO);
 
-  if (p.in_check())
-      phase = EVASION;
+  if (pos.checkers())
+      stage = EVASION;
 
   else if (d > DEPTH_QS_NO_CHECKS)
-      phase = QSEARCH_0;
+      stage = QSEARCH_0;
 
   else if (d > DEPTH_QS_RECAPTURES)
   {
-      phase = QSEARCH_1;
+      stage = QSEARCH_1;
 
-      // Skip TT move if is not a capture or a promotion, this avoids qsearch
+      // Skip TT move if is not a capture or a promotion. This avoids qsearch
       // tree explosion due to a possible perpetual check or similar rare cases
       // when TT table is full.
-      if (ttm && !pos.is_capture_or_promotion(ttm))
+      if (ttm && !pos.capture_or_promotion(ttm))
           ttm = MOVE_NONE;
   }
   else
   {
-      phase = RECAPTURE;
-      recaptureSquare = sq;
+      stage = RECAPTURE;
+      recaptureSquare = s;
       ttm = MOVE_NONE;
   }
 
-  ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE);
+  ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE);
   end += (ttMove != MOVE_NONE);
 }
 
-MovePicker::MovePicker(const Position& p, Move ttm, const History& h, PieceType pt)
-                       : pos(p), H(h), cur(moves), end(moves) {
+MovePicker::MovePicker(const Position& p, Move ttm, const HistoryStats& h, PieceType pt)
+                       : pos(p), history(h), cur(moves), end(moves) {
 
-  assert(!pos.in_check());
+  assert(!pos.checkers());
 
-  phase = PROBCUT;
+  stage = PROBCUT;
 
-  // In ProbCut we generate only captures better than parent's captured piece
-  captureThreshold = PieceValue[Mg][pt];
-  ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE);
+  // In ProbCut we generate only captures that are better than the parent's
+  // captured piece.
+  captureThreshold = PieceValue[MG][pt];
+  ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE);
 
-  if (ttMove && (!pos.is_capture(ttMove) ||  pos.see(ttMove) <= captureThreshold))
+  if (ttMove && (!pos.capture(ttMove) || pos.see(ttMove) <= captureThreshold))
       ttMove = MOVE_NONE;
 
   end += (ttMove != MOVE_NONE);
 }
 
 
-/// MovePicker::score_captures(), MovePicker::score_noncaptures() and
-/// MovePicker::score_evasions() assign a numerical move ordering score
-/// to each move in a move list.  The moves with highest scores will be
-/// picked first by next_move().
-
-void MovePicker::score_captures() {
+/// score() assign a numerical value to each move in a move list. The moves with
+/// highest values will be picked first.
+template<>
+void MovePicker::score<CAPTURES>() {
   // Winning and equal captures in the main search are ordered by MVV/LVA.
   // Suprisingly, this appears to perform slightly better than SEE based
   // move ordering. The reason is probably that in a position with a winning
@@ -156,89 +155,114 @@ void MovePicker::score_captures() {
   // where it is possible to recapture with the hanging piece). Exchanging
   // big pieces before capturing a hanging piece probably helps to reduce
   // the subtree size.
-  // In main search we want to push captures with negative SEE values to
-  // badCaptures[] array, but instead of doing it now we delay till when
-  // the move has been picked up in pick_move_from_list(), this way we save
-  // some SEE calls in case we get a cutoff (idea from Pablo Vazquez).
+  // In main search we want to push captures with negative SEE values to the
+  // badCaptures[] array, but instead of doing it now we delay until the move
+  // has been picked up in pick_move_from_list(). This way we save some SEE
+  // calls in case we get a cutoff.
   Move m;
 
-  for (MoveStack* it = moves; it != end; ++it)
+  for (ExtMove* it = moves; it != end; ++it)
   {
       m = it->move;
-      it->score =  PieceValue[Mg][pos.piece_on(to_sq(m))]
-                 - type_of(pos.piece_moved(m));
+      it->value =  PieceValue[MG][pos.piece_on(to_sq(m))]
+                 - Value(type_of(pos.moved_piece(m)));
 
-      if (type_of(m) == PROMOTION)
-          it->score += PieceValue[Mg][promotion_type(m)];
+      if (type_of(m) == ENPASSANT)
+          it->value += PieceValue[MG][PAWN];
+
+      else if (type_of(m) == PROMOTION)
+          it->value += PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN];
   }
 }
 
-void MovePicker::score_noncaptures() {
+template<>
+void MovePicker::score<QUIETS>() {
 
   Move m;
 
-  for (MoveStack* it = moves; it != end; ++it)
+  for (ExtMove* it = moves; it != end; ++it)
   {
       m = it->move;
-      it->score = H.value(pos.piece_moved(m), to_sq(m));
+      it->value = history[pos.moved_piece(m)][to_sq(m)];
   }
 }
 
-void MovePicker::score_evasions() {
+template<>
+void MovePicker::score<EVASIONS>() {
   // Try good captures ordered by MVV/LVA, then non-captures if destination square
   // is not under attack, ordered by history value, then bad-captures and quiet
-  // moves with a negative SEE. This last group is ordered by the SEE score.
+  // moves with a negative SEE. This last group is ordered by the SEE value.
   Move m;
-  int seeScore;
+  Value see;
 
-  if (end < moves + 2)
-      return;
-
-  for (MoveStack* it = moves; it != end; ++it)
+  for (ExtMove* it = moves; it != end; ++it)
   {
       m = it->move;
-      if ((seeScore = pos.see_sign(m)) < 0)
-          it->score = seeScore - History::MaxValue; // Be sure we are at the bottom
-      else if (pos.is_capture(m))
-          it->score =  PieceValue[Mg][pos.piece_on(to_sq(m))]
-                     - type_of(pos.piece_moved(m)) + History::MaxValue;
+      if ((see = pos.see_sign(m)) < VALUE_ZERO)
+          it->value = see - HistoryStats::Max; // At the bottom
+
+      else if (pos.capture(m))
+          it->value =  PieceValue[MG][pos.piece_on(to_sq(m))]
+                     - Value(type_of(pos.moved_piece(m))) + HistoryStats::Max;
       else
-          it->score = H.value(pos.piece_moved(m), to_sq(m));
+          it->value = history[pos.moved_piece(m)][to_sq(m)];
   }
 }
 
 
-/// MovePicker::generate_next() generates, scores and sorts the next bunch of moves,
-/// when there are no more moves to try for the current phase.
+/// generate_next_stage() generates, scores and sorts the next bunch of moves,
+/// when there are no more moves to try for the current stage.
 
-void MovePicker::generate_next() {
+void MovePicker::generate_next_stage() {
 
   cur = moves;
 
-  switch (++phase) {
+  switch (++stage) {
 
   case CAPTURES_S1: case CAPTURES_S3: case CAPTURES_S4: case CAPTURES_S5: case CAPTURES_S6:
       end = generate<CAPTURES>(pos, moves);
-      score_captures();
+      score<CAPTURES>();
       return;
 
   case KILLERS_S1:
       cur = killers;
       end = cur + 2;
+
+      killers[0].move = ss->killers[0];
+      killers[1].move = ss->killers[1];
+      killers[2].move = killers[3].move = MOVE_NONE;
+      killers[4].move = killers[5].move = MOVE_NONE;
+
+      // Please note that following code is racy and could yield to rare (less
+      // than 1 out of a million) duplicated entries in SMP case. This is harmless.
+
+      // Be sure countermoves are different from killers
+      for (int i = 0; i < 2; ++i)
+          if (   countermoves[i] != (cur+0)->move
+              && countermoves[i] != (cur+1)->move)
+              (end++)->move = countermoves[i];
+
+      // Be sure followupmoves are different from killers and countermoves
+      for (int i = 0; i < 2; ++i)
+          if (   followupmoves[i] != (cur+0)->move
+              && followupmoves[i] != (cur+1)->move
+              && followupmoves[i] != (cur+2)->move
+              && followupmoves[i] != (cur+3)->move)
+              (end++)->move = followupmoves[i];
       return;
 
   case QUIETS_1_S1:
       endQuiets = end = generate<QUIETS>(pos, moves);
-      score_noncaptures();
-      end = std::partition(cur, end, has_positive_score);
-      sort<MoveStack>(cur, end);
+      score<QUIETS>();
+      end = std::partition(cur, end, has_positive_value);
+      insertion_sort(cur, end);
       return;
 
   case QUIETS_2_S1:
       cur = end;
       end = endQuiets;
       if (depth >= 3 * ONE_PLY)
-          sort<MoveStack>(cur, end);
+          insertion_sort(cur, end);
       return;
 
   case BAD_CAPTURES_S1:
@@ -249,7 +273,8 @@ void MovePicker::generate_next() {
 
   case EVASIONS_S2:
       end = generate<EVASIONS>(pos, moves);
-      score_evasions();
+      if (end > moves + 1)
+          score<EVASIONS>();
       return;
 
   case QUIET_CHECKS_S3:
@@ -257,7 +282,9 @@ void MovePicker::generate_next() {
       return;
 
   case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: case RECAPTURE:
-      phase = STOP;
+      stage = STOP;
+      /* Fall through */
+
   case STOP:
       end = cur + 1; // Avoid another next_phase() call
       return;
@@ -268,11 +295,10 @@ void MovePicker::generate_next() {
 }
 
 
-/// 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. It picks the move with the biggest score from a list
-/// of generated moves taking care not to return the tt move if has already been
-/// searched previously.
+/// 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. It picks the move with the biggest value from a list of generated moves
+/// taking care not to return the ttMove if it has already been searched.
 template<>
 Move MovePicker::next_move<false>() {
 
@@ -281,21 +307,19 @@ Move MovePicker::next_move<false>() {
   while (true)
   {
       while (cur == end)
-          generate_next();
+          generate_next_stage();
 
-      switch (phase) {
+      switch (stage) {
 
       case MAIN_SEARCH: case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT:
-          cur++;
+          ++cur;
           return ttMove;
 
       case CAPTURES_S1:
           move = pick_best(cur++, end)->move;
           if (move != ttMove)
           {
-              assert(captureThreshold <= 0); // Otherwise we cannot use see_sign()
-
-              if (pos.see_sign(move) >= captureThreshold)
+              if (pos.see_sign(move) >= VALUE_ZERO)
                   return move;
 
               // Losing capture, move it to the tail of the array
@@ -306,9 +330,9 @@ Move MovePicker::next_move<false>() {
       case KILLERS_S1:
           move = (cur++)->move;
           if (    move != MOVE_NONE
-              &&  pos.is_pseudo_legal(move)
               &&  move != ttMove
-              && !pos.is_capture(move))
+              &&  pos.pseudo_legal(move)
+              && !pos.capture(move))
               return move;
           break;
 
@@ -316,7 +340,11 @@ Move MovePicker::next_move<false>() {
           move = (cur++)->move;
           if (   move != ttMove
               && move != killers[0].move
-              && move != killers[1].move)
+              && move != killers[1].move
+              && move != killers[2].move
+              && move != killers[3].move
+              && move != killers[4].move
+              && move != killers[5].move)
               return move;
           break;
 
@@ -359,6 +387,6 @@ Move MovePicker::next_move<false>() {
 
 /// Version of next_move() to use at split point nodes where the move is grabbed
 /// from the split point's shared MovePicker object. This function is not thread
-/// safe so should be lock protected by the caller.
+/// safe so must be lock protected by the caller.
 template<>
-Move MovePicker::next_move<true>() { return ss->sp->mp->next_move<false>(); }
+Move MovePicker::next_move<true>() { return ss->splitPoint->movePicker->next_move<false>(); }

src/movepick.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,15 +17,61 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined MOVEPICK_H_INCLUDED
+#ifndef MOVEPICK_H_INCLUDED
 #define MOVEPICK_H_INCLUDED
 
-#include "history.h"
+#include <algorithm> // For std::max
+#include <cstring>   // For std::memset
+
+#include "movegen.h"
 #include "position.h"
 #include "search.h"
 #include "types.h"
 
 
+/// The Stats struct stores moves statistics. According to the template parameter
+/// the class can store History, Gains and Countermoves. History records how often
+/// different moves have been successful or unsuccessful during the current search
+/// and is used for reduction and move ordering decisions. Gains records the move's
+/// best evaluation gain from one ply to the next and is used for pruning decisions.
+/// Countermoves store the move that refute a previous one. Entries are stored
+/// using only the moving piece and destination square, hence two moves with
+/// different origin but same destination and piece will be considered identical.
+template<bool Gain, typename T>
+struct Stats {
+
+  static const Value Max = Value(2000);
+
+  const T* operator[](Piece pc) const { return table[pc]; }
+  void clear() { std::memset(table, 0, sizeof(table)); }
+
+  void update(Piece pc, Square to, Move m) {
+
+    if (m == table[pc][to].first)
+        return;
+
+    table[pc][to].second = table[pc][to].first;
+    table[pc][to].first = m;
+  }
+
+  void update(Piece pc, Square to, Value v) {
+
+    if (Gain)
+        table[pc][to] = std::max(v, table[pc][to] - 1);
+
+    else if (abs(table[pc][to] + v) < Max)
+        table[pc][to] +=  v;
+  }
+
+private:
+  T table[PIECE_NB][SQUARE_NB];
+};
+
+typedef Stats< true, Value> GainsStats;
+typedef Stats<false, Value> HistoryStats;
+typedef Stats<false, std::pair<Move, Move> > MovesStats;
+
+
 /// 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,
@@ -38,27 +84,29 @@ class MovePicker {
   MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC
 
 public:
-  MovePicker(const Position&, Move, Depth, const History&, Search::Stack*, Value);
-  MovePicker(const Position&, Move, Depth, const History&, Square);
-  MovePicker(const Position&, Move, const History&, PieceType);
+  MovePicker(const Position&, Move, Depth, const HistoryStats&, Square);
+  MovePicker(const Position&, Move, const HistoryStats&, PieceType);
+  MovePicker(const Position&, Move, Depth, const HistoryStats&, Move*, Move*, Search::Stack*);
+
   template<bool SpNode> Move next_move();
 
 private:
-  void score_captures();
-  void score_noncaptures();
-  void score_evasions();
-  void generate_next();
+  template<GenType> void score();
+  void generate_next_stage();
 
   const Position& pos;
-  const History& H;
+  const HistoryStats& history;
   Search::Stack* ss;
+  Move* countermoves;
+  Move* followupmoves;
   Depth depth;
   Move ttMove;
-  MoveStack killers[2];
+  ExtMove killers[6];
   Square recaptureSquare;
-  int captureThreshold, phase;
-  MoveStack *cur, *end, *endQuiets, *endBadCaptures;
-  MoveStack moves[MAX_MOVES];
+  Value captureThreshold;
+  int stage;
+  ExtMove *cur, *end, *endQuiets, *endBadCaptures;
+  ExtMove moves[MAX_MOVES];
 };
 
-#endif // !defined(MOVEPICK_H_INCLUDED)
+#endif // #ifndef MOVEPICK_H_INCLUDED

src/notation.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,7 +20,7 @@
 #include <cassert>
 #include <iomanip>
 #include <sstream>
-#include <string>
+#include <stack>
 
 #include "movegen.h"
 #include "notation.h"
@@ -28,7 +28,7 @@
 
 using namespace std;
 
-static const char* PieceToChar = " PNBRQK  pnbrqk";
+static const char* PieceToChar[COLOR_NB] = { " PNBRQK", " pnbrqk" };
 
 
 /// score_to_uci() converts a value to a string suitable for use with the UCI
@@ -40,23 +40,23 @@ static const char* PieceToChar = " PNBRQK  pnbrqk";
 
 string score_to_uci(Value v, Value alpha, Value beta) {
 
-  stringstream s;
+  stringstream ss;
 
   if (abs(v) < VALUE_MATE_IN_MAX_PLY)
-      s << "cp " << v * 100 / int(PawnValueMg);
+      ss << "cp " << v * 100 / PawnValueEg;
   else
-      s << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
+      ss << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
 
-  s << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : "");
+  ss << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : "");
 
-  return s.str();
+  return ss.str();
 }
 
 
 /// move_to_uci() converts a move to a string in coordinate notation
 /// (g1f3, a7a8q, etc.). The only special case is castling moves, where we print
 /// in the e1g1 notation in normal chess mode, and in e1h1 notation in chess960
-/// mode. Internally castle moves are always coded as "king captures rook".
+/// mode. Internally castling moves are always encoded as "king captures rook".
 
 const string move_to_uci(Move m, bool chess960) {
 
@@ -69,13 +69,13 @@ const string move_to_uci(Move m, bool chess960) {
   if (m == MOVE_NULL)
       return "0000";
 
-  if (type_of(m) == CASTLE && !chess960)
-      to = (to > from ? FILE_G : FILE_C) | rank_of(from);
+  if (type_of(m) == CASTLING && !chess960)
+      to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
 
-  string move = square_to_string(from) + square_to_string(to);
+  string move = to_string(from) + to_string(to);
 
   if (type_of(m) == PROMOTION)
-      move += PieceToChar[make_piece(BLACK, promotion_type(m))]; // Lower case
+      move += PieceToChar[BLACK][promotion_type(m)]; // Lower case
 
   return move;
 }
@@ -89,9 +89,9 @@ Move move_from_uci(const Position& pos, string& str) {
   if (str.length() == 5) // Junior could send promotion piece in uppercase
       str[4] = char(tolower(str[4]));
 
-  for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
-      if (str == move_to_uci(ml.move(), pos.is_chess960()))
-          return ml.move();
+  for (MoveList<LEGAL> it(pos); *it; ++it)
+      if (str == move_to_uci(*it, pos.is_chess960()))
+          return *it;
 
   return MOVE_NONE;
 }
@@ -108,10 +108,9 @@ const string move_to_san(Position& pos, Move m) {
   if (m == MOVE_NULL)
       return "(null)";
 
-  assert(pos.move_is_legal(m));
+  assert(MoveList<LEGAL>(pos).contains(m));
 
-  Bitboard attackers;
-  bool ambiguousMove, ambiguousFile, ambiguousRank;
+  Bitboard others, b;
   string san;
   Color us = pos.side_to_move();
   Square from = from_sq(m);
@@ -119,58 +118,50 @@ const string move_to_san(Position& pos, Move m) {
   Piece pc = pos.piece_on(from);
   PieceType pt = type_of(pc);
 
-  if (type_of(m) == CASTLE)
+  if (type_of(m) == CASTLING)
       san = to > from ? "O-O" : "O-O-O";
   else
   {
       if (pt != PAWN)
       {
-          san = PieceToChar[pt]; // Upper case
+          san = PieceToChar[WHITE][pt]; // Upper case
 
-          // Disambiguation if we have more then one piece with destination 'to'
-          // note that for pawns is not needed because starting file is explicit.
-          ambiguousMove = ambiguousFile = ambiguousRank = false;
+          // A disambiguation occurs if we have more then one piece of type 'pt'
+          // that can reach 'to' with a legal move.
+          others = b = (pos.attacks_from(pc, to) & pos.pieces(us, pt)) ^ from;
 
-          attackers = (pos.attacks_from(pc, to) & pos.pieces(us, pt)) ^ from;
-
-          while (attackers)
+          while (b)
           {
-              Square sq = pop_lsb(&attackers);
-
-              // Pinned pieces are not included in the possible sub-set
-              if (!pos.pl_move_is_legal(make_move(sq, to), pos.pinned_pieces()))
-                  continue;
-
-              ambiguousFile |= file_of(sq) == file_of(from);
-              ambiguousRank |= rank_of(sq) == rank_of(from);
-              ambiguousMove = true;
+              Square s = pop_lsb(&b);
+              if (!pos.legal(make_move(s, to), pos.pinned_pieces(us)))
+                  others ^= s;
           }
 
-          if (ambiguousMove)
-          {
-              if (!ambiguousFile)
-                  san += file_to_char(file_of(from));
+          if (!others)
+          { /* Disambiguation is not needed */ }
 
-              else if (!ambiguousRank)
-                  san += rank_to_char(rank_of(from));
+          else if (!(others & file_bb(from)))
+              san += to_char(file_of(from));
 
-              else
-                  san += square_to_string(from);
-          }
+          else if (!(others & rank_bb(from)))
+              san += to_char(rank_of(from));
+
+          else
+              san += to_string(from);
       }
-      else if (pos.is_capture(m))
-          san = file_to_char(file_of(from));
+      else if (pos.capture(m))
+          san = to_char(file_of(from));
 
-      if (pos.is_capture(m))
+      if (pos.capture(m))
           san += 'x';
 
-      san += square_to_string(to);
+      san += to_string(to);
 
       if (type_of(m) == PROMOTION)
-          san += string("=") + PieceToChar[promotion_type(m)];
+          san += string("=") + PieceToChar[WHITE][promotion_type(m)];
   }
 
-  if (pos.move_gives_check(m, CheckInfo(pos)))
+  if (pos.gives_check(m, CheckInfo(pos)))
   {
       StateInfo st;
       pos.do_move(m, st);
@@ -184,9 +175,9 @@ const string move_to_san(Position& pos, Move m) {
 
 /// pretty_pv() formats human-readable search information, typically to be
 /// appended to the search log file. It uses the two helpers below to pretty
-/// format time and score respectively.
+/// format the time and score respectively.
 
-static string time_to_string(int64_t msecs) {
+static string format(int64_t msecs) {
 
   const int MSecMinute = 1000 * 60;
   const int MSecHour   = 1000 * 60 * 60;
@@ -195,77 +186,71 @@ static string time_to_string(int64_t msecs) {
   int64_t minutes =  (msecs % MSecHour) / MSecMinute;
   int64_t seconds = ((msecs % MSecHour) % MSecMinute) / 1000;
 
-  stringstream s;
+  stringstream ss;
 
   if (hours)
-      s << hours << ':';
+      ss << hours << ':';
 
-  s << setfill('0') << setw(2) << minutes << ':' << setw(2) << seconds;
+  ss << setfill('0') << setw(2) << minutes << ':' << setw(2) << seconds;
 
-  return s.str();
+  return ss.str();
 }
 
-static string score_to_string(Value v) {
+static string format(Value v) {
 
-  stringstream s;
+  stringstream ss;
 
   if (v >= VALUE_MATE_IN_MAX_PLY)
-      s << "#" << (VALUE_MATE - v + 1) / 2;
+      ss << "#" << (VALUE_MATE - v + 1) / 2;
 
   else if (v <= VALUE_MATED_IN_MAX_PLY)
-      s << "-#" << (VALUE_MATE + v) / 2;
+      ss << "-#" << (VALUE_MATE + v) / 2;
 
   else
-      s << setprecision(2) << fixed << showpos << float(v) / PawnValueMg;
+      ss << setprecision(2) << fixed << showpos << double(v) / PawnValueEg;
 
-  return s.str();
+  return ss.str();
 }
 
 string pretty_pv(Position& pos, int depth, Value value, int64_t msecs, Move pv[]) {
 
-  const int64_t K = 1000;
-  const int64_t M = 1000000;
+  const uint64_t K = 1000;
+  const uint64_t M = 1000000;
 
-  StateInfo state[MAX_PLY_PLUS_2], *st = state;
+  std::stack<StateInfo> st;
   Move* m = pv;
-  string san, padding;
-  size_t length;
-  stringstream s;
+  string san, str, padding;
+  stringstream ss;
 
-  s << setw(2) << depth
-    << setw(8) << score_to_string(value)
-    << setw(8) << time_to_string(msecs);
+  ss << setw(2) << depth << setw(8) << format(value) << setw(8) << format(msecs);
 
   if (pos.nodes_searched() < M)
-      s << setw(8) << pos.nodes_searched() / 1 << "  ";
+      ss << setw(8) << pos.nodes_searched() / 1 << "  ";
 
   else if (pos.nodes_searched() < K * M)
-      s << setw(7) << pos.nodes_searched() / K << "K  ";
+      ss << setw(7) << pos.nodes_searched() / K << "K  ";
 
   else
-      s << setw(7) << pos.nodes_searched() / M << "M  ";
+      ss << setw(7) << pos.nodes_searched() / M << "M  ";
 
-  padding = string(s.str().length(), ' ');
-  length = padding.length();
+  str = ss.str();
+  padding = string(str.length(), ' ');
 
   while (*m != MOVE_NONE)
   {
-      san = move_to_san(pos, *m);
+      san = move_to_san(pos, *m) + ' ';
 
-      if (length + san.length() > 80)
-      {
-          s << "\n" + padding;
-          length = padding.length();
-      }
+      if ((str.length() + san.length()) % 80 <= san.length()) // Exceed 80 cols
+          str += "\n" + padding;
 
-      s << san << ' ';
-      length += san.length() + 1;
+      str += san;
 
-      pos.do_move(*m++, *st++);
+      st.push(StateInfo());
+      pos.do_move(*m++, st.top());
   }
 
   while (m != pv)
       pos.undo_move(*--m);
 
-  return s.str();
+  return str;
 }

src/notation.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(NOTATION_H_INCLUDED)
+#ifndef NOTATION_H_INCLUDED
 #define NOTATION_H_INCLUDED
 
 #include <string>
@@ -32,4 +32,4 @@ const std::string move_to_uci(Move m, bool chess960);
 const std::string move_to_san(Position& pos, Move m);
 std::string pretty_pv(Position& pos, int depth, Value score, int64_t msecs, Move pv[]);
 
-#endif // !defined(NOTATION_H_INCLUDED)
+#endif // #ifndef NOTATION_H_INCLUDED

src/pawns.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <algorithm>
 #include <cassert>
 
 #include "bitboard.h"
@@ -29,238 +30,264 @@ namespace {
   #define V Value
   #define S(mg, eg) make_score(mg, eg)
 
-  // Doubled pawn penalty by opposed flag and file
-  const Score DoubledPawnPenalty[2][8] = {
-  { S(13, 43), S(20, 48), S(23, 48), S(23, 48),
-    S(23, 48), S(23, 48), S(20, 48), S(13, 43) },
-  { S(13, 43), S(20, 48), S(23, 48), S(23, 48),
-    S(23, 48), S(23, 48), S(20, 48), S(13, 43) }};
+  // Doubled pawn penalty by file
+  const Score Doubled[FILE_NB] = {
+    S(13, 43), S(20, 48), S(23, 48), S(23, 48),
+    S(23, 48), S(23, 48), S(20, 48), S(13, 43) };
 
   // Isolated pawn penalty by opposed flag and file
-  const Score IsolatedPawnPenalty[2][8] = {
+  const Score Isolated[2][FILE_NB] = {
   { S(37, 45), S(54, 52), S(60, 52), S(60, 52),
     S(60, 52), S(60, 52), S(54, 52), S(37, 45) },
   { S(25, 30), S(36, 35), S(40, 35), S(40, 35),
-    S(40, 35), S(40, 35), S(36, 35), S(25, 30) }};
+    S(40, 35), S(40, 35), S(36, 35), S(25, 30) } };
 
   // Backward pawn penalty by opposed flag and file
-  const Score BackwardPawnPenalty[2][8] = {
+  const Score Backward[2][FILE_NB] = {
   { S(30, 42), S(43, 46), S(49, 46), S(49, 46),
     S(49, 46), S(49, 46), S(43, 46), S(30, 42) },
   { S(20, 28), S(29, 31), S(33, 31), S(33, 31),
-    S(33, 31), S(33, 31), S(29, 31), S(20, 28) }};
+    S(33, 31), S(33, 31), S(29, 31), S(20, 28) } };
 
-  // Pawn chain membership bonus by file
-  const Score ChainBonus[8] = {
-    S(11,-1), S(13,-1), S(13,-1), S(14,-1),
-    S(14,-1), S(13,-1), S(13,-1), S(11,-1)
-  };
+  // Connected pawn bonus by file and rank (initialized by formula)
+  Score Connected[FILE_NB][RANK_NB];
 
   // Candidate passed pawn bonus by rank
-  const Score CandidateBonus[8] = {
+  const Score CandidatePassed[RANK_NB] = {
     S( 0, 0), S( 6, 13), S(6,13), S(14,29),
-    S(34,68), S(83,166), S(0, 0), S( 0, 0)
-  };
+    S(34,68), S(83,166), S(0, 0), S( 0, 0) };
 
-  const Score PawnStructureWeight = S(233, 201);
+  // Bonus for file distance of the two outermost pawns
+  const Score PawnsFileSpan = S(0, 15);
 
-  // Weakness of our pawn shelter in front of the king indexed by [king pawn][rank]
-  const Value ShelterWeakness[2][8] =
-  { { V(141), V(0), V(38), V(102), V(128), V(141), V(141) },
-    { V( 61), V(0), V(16), V( 44), V( 56), V( 61), V( 61) } };
+  // Unsupported pawn penalty
+  const Score UnsupportedPawnPenalty = S(20, 10);
 
-  // Danger of enemy pawns moving toward our king indexed by [pawn blocked][rank]
-  const Value StormDanger[2][8] =
-  { { V(26), V(0), V(128), V(51), V(26) },
-    { V(13), V(0), V( 64), V(25), V(13) } };
+  // Weakness of our pawn shelter in front of the king indexed by [rank]
+  const Value ShelterWeakness[RANK_NB] =
+  { V(100), V(0), V(27), V(73), V(92), V(101), V(101) };
+
+  // Danger of enemy pawns moving toward our king indexed by
+  // [no friendly pawn | pawn unblocked | pawn blocked][rank of enemy pawn]
+  const Value StormDanger[3][RANK_NB] = {
+  { V( 0),  V(64), V(128), V(51), V(26) },
+  { V(26),  V(32), V( 96), V(38), V(20) },
+  { V( 0),  V( 0), V(160), V(25), V(13) } };
 
   // Max bonus for king safety. Corresponds to start position with all the pawns
-  // in front of the king and no enemy pawn on the horizont.
+  // in front of the king and no enemy pawn on the horizon.
   const Value MaxSafetyBonus = V(263);
 
   #undef S
   #undef V
+
+  template<Color Us>
+  Score evaluate(const Position& pos, Pawns::Entry* e) {
+
+    const Color  Them  = (Us == WHITE ? BLACK    : WHITE);
+    const Square Up    = (Us == WHITE ? DELTA_N  : DELTA_S);
+    const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW);
+    const Square Left  = (Us == WHITE ? DELTA_NW : DELTA_SE);
+
+    Bitboard b, p, doubled;
+    Square s;
+    File f;
+    bool passed, isolated, opposed, connected, backward, candidate, unsupported;
+    Score value = SCORE_ZERO;
+    const Square* pl = pos.list<PAWN>(Us);
+
+    Bitboard ourPawns = pos.pieces(Us, PAWN);
+    Bitboard theirPawns = pos.pieces(Them, PAWN);
+
+    e->passedPawns[Us] = e->candidatePawns[Us] = 0;
+    e->kingSquares[Us] = SQ_NONE;
+    e->semiopenFiles[Us] = 0xFF;
+    e->pawnAttacks[Us] = shift_bb<Right>(ourPawns) | shift_bb<Left>(ourPawns);
+    e->pawnsOnSquares[Us][BLACK] = popcount<Max15>(ourPawns & DarkSquares);
+    e->pawnsOnSquares[Us][WHITE] = pos.count<PAWN>(Us) - e->pawnsOnSquares[Us][BLACK];
+
+    // Loop through all pawns of the current color and score each pawn
+    while ((s = *pl++) != SQ_NONE)
+    {
+        assert(pos.piece_on(s) == make_piece(Us, PAWN));
+
+        f = file_of(s);
+
+        // This file cannot be semi-open
+        e->semiopenFiles[Us] &= ~(1 << f);
+
+        // Previous rank
+        p = rank_bb(s - pawn_push(Us));
+
+        // Our rank plus previous one
+        b = rank_bb(s) | p;
+
+        // Flag the pawn as passed, isolated, doubled,
+        // unsupported or connected (but not the backward one).
+        connected   =   ourPawns   & adjacent_files_bb(f) & b;
+        unsupported = !(ourPawns   & adjacent_files_bb(f) & p);
+        isolated    = !(ourPawns   & adjacent_files_bb(f));
+        doubled     =   ourPawns   & forward_bb(Us, s);
+        opposed     =   theirPawns & forward_bb(Us, s);
+        passed      = !(theirPawns & passed_pawn_mask(Us, s));
+
+        // Test for backward pawn.
+        // If the pawn is passed, isolated, or connected it cannot be
+        // backward. If there are friendly pawns behind on adjacent files
+        // or if it can capture an enemy pawn it cannot be backward either.
+        if (   (passed | isolated | connected)
+            || (ourPawns & pawn_attack_span(Them, s))
+            || (pos.attacks_from<PAWN>(s, Us) & theirPawns))
+            backward = false;
+        else
+        {
+            // We now know that there are no friendly pawns beside or behind this
+            // pawn on adjacent files. We now check whether the pawn is
+            // backward by looking in the forward direction on the adjacent
+            // files, and picking the closest pawn there.
+            b = pawn_attack_span(Us, s) & (ourPawns | theirPawns);
+            b = pawn_attack_span(Us, s) & rank_bb(backmost_sq(Us, b));
+
+            // If we have an enemy pawn in the same or next rank, the pawn is
+            // backward because it cannot advance without being captured.
+            backward = (b | shift_bb<Up>(b)) & theirPawns;
+        }
+
+        assert(opposed | passed | (pawn_attack_span(Us, s) & theirPawns));
+
+        // A not-passed pawn is a candidate to become passed, if it is free to
+        // advance and if the number of friendly pawns beside or behind this
+        // pawn on adjacent files is higher than or equal to the number of
+        // enemy pawns in the forward direction on the adjacent files.
+        candidate =   !(opposed | passed | backward | isolated)
+                   && (b = pawn_attack_span(Them, s + pawn_push(Us)) & ourPawns) != 0
+                   &&  popcount<Max15>(b) >= popcount<Max15>(pawn_attack_span(Us, s) & theirPawns);
+
+        // Passed pawns will be properly scored in evaluation because we need
+        // full attack info to evaluate passed pawns. Only the frontmost passed
+        // pawn on each file is considered a true passed pawn.
+        if (passed && !doubled)
+            e->passedPawns[Us] |= s;
+
+        // Score this pawn
+        if (isolated)
+            value -= Isolated[opposed][f];
+
+        if (unsupported && !isolated)
+            value -= UnsupportedPawnPenalty;
+
+        if (doubled)
+            value -= Doubled[f] / rank_distance(s, lsb(doubled));
+
+        if (backward)
+            value -= Backward[opposed][f];
+
+        if (connected)
+            value += Connected[f][relative_rank(Us, s)];
+
+        if (candidate)
+        {
+            value += CandidatePassed[relative_rank(Us, s)];
+
+            if (!doubled)
+                e->candidatePawns[Us] |= s;
+        }
+    }
+
+    // In endgame it's better to have pawns on both wings. So give a bonus according
+    // to file distance between left and right outermost pawns.
+    if (pos.count<PAWN>(Us) > 1)
+    {
+        b = e->semiopenFiles[Us] ^ 0xFF;
+        value += PawnsFileSpan * int(msb(b) - lsb(b));
+    }
+
+    return value;
+  }
+
+} // namespace
+
+namespace Pawns {
+
+/// init() initializes some tables by formula instead of hard-coding their values
+
+void init() {
+
+  const int bonusesByFile[8] = { 1, 3, 3, 4, 4, 3, 3, 1 };
+  int bonus;
+
+  for (Rank r = RANK_1; r < RANK_8; ++r)
+      for (File f = FILE_A; f <= FILE_H; ++f)
+      {
+          bonus = r * (r-1) * (r-2) + bonusesByFile[f] * (r/2 + 1);
+          Connected[f][r] = make_score(bonus, bonus);
+      }
 }
 
 
-/// PawnTable::probe() takes a position object as input, computes a PawnEntry
-/// object, and returns a pointer to it. The result is also stored in a hash
-/// table, so we don't have to recompute everything when the same pawn structure
-/// occurs again.
+/// probe() takes a position object as input, computes a Entry object, and returns
+/// a pointer to it. The result is also stored in a hash table, so we don't have
+/// to recompute everything when the same pawn structure occurs again.
 
-PawnEntry* PawnTable::probe(const Position& pos) {
+Entry* probe(const Position& pos, Table& entries) {
 
   Key key = pos.pawn_key();
-  PawnEntry* e = entries[key];
+  Entry* e = entries[key];
 
-  // If e->key matches the position's pawn hash key, it means that we
-  // have analysed this pawn structure before, and we can simply return
-  // the information we found the last time instead of recomputing it.
   if (e->key == key)
       return e;
 
   e->key = key;
-  e->passedPawns[WHITE] = e->passedPawns[BLACK] = 0;
-  e->kingSquares[WHITE] = e->kingSquares[BLACK] = SQ_NONE;
-  e->halfOpenFiles[WHITE] = e->halfOpenFiles[BLACK] = 0xFF;
-
-  Bitboard wPawns = pos.pieces(WHITE, PAWN);
-  Bitboard bPawns = pos.pieces(BLACK, PAWN);
-  e->pawnAttacks[WHITE] = ((wPawns & ~FileHBB) << 9) | ((wPawns & ~FileABB) << 7);
-  e->pawnAttacks[BLACK] = ((bPawns & ~FileHBB) >> 7) | ((bPawns & ~FileABB) >> 9);
-
-  e->value =  evaluate_pawns<WHITE>(pos, wPawns, bPawns, e)
-            - evaluate_pawns<BLACK>(pos, bPawns, wPawns, e);
-
-  e->value = apply_weight(e->value, PawnStructureWeight);
-
+  e->value = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
   return e;
 }
 
 
-/// PawnTable::evaluate_pawns() evaluates each pawn of the given color
-
-template<Color Us>
-Score PawnTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
-                                Bitboard theirPawns, PawnEntry* e) {
-
-  const Color Them = (Us == WHITE ? BLACK : WHITE);
-
-  Bitboard b;
-  Square s;
-  File f;
-  Rank r;
-  bool passed, isolated, doubled, opposed, chain, backward, candidate;
-  Score value = SCORE_ZERO;
-  const Square* pl = pos.piece_list(Us, PAWN);
-
-  // Loop through all pawns of the current color and score each pawn
-  while ((s = *pl++) != SQ_NONE)
-  {
-      assert(pos.piece_on(s) == make_piece(Us, PAWN));
-
-      f = file_of(s);
-      r = rank_of(s);
-
-      // This file cannot be half open
-      e->halfOpenFiles[Us] &= ~(1 << f);
-
-      // Our rank plus previous one. Used for chain detection
-      b = rank_bb(r) | rank_bb(Us == WHITE ? r - Rank(1) : r + Rank(1));
-
-      // Flag the pawn as passed, isolated, doubled or member of a pawn
-      // chain (but not the backward one).
-      chain    =   ourPawns   & adjacent_files_bb(f) & b;
-      isolated = !(ourPawns   & adjacent_files_bb(f));
-      doubled  =   ourPawns   & forward_bb(Us, s);
-      opposed  =   theirPawns & forward_bb(Us, s);
-      passed   = !(theirPawns & passed_pawn_mask(Us, s));
-
-      // Test for backward pawn
-      backward = false;
-
-      // If the pawn is passed, isolated, or member of a pawn chain it cannot
-      // be backward. If there are friendly pawns behind on adjacent files
-      // or if can capture an enemy pawn it cannot be backward either.
-      if (   !(passed | isolated | chain)
-          && !(ourPawns & attack_span_mask(Them, s))
-          && !(pos.attacks_from<PAWN>(s, Us) & theirPawns))
-      {
-          // We now know that there are no friendly pawns beside or behind this
-          // pawn on adjacent files. We now check whether the pawn is
-          // backward by looking in the forward direction on the adjacent
-          // files, and seeing whether we meet a friendly or an enemy pawn first.
-          b = pos.attacks_from<PAWN>(s, Us);
-
-          // Note that we are sure to find something because pawn is not passed
-          // nor isolated, so loop is potentially infinite, but it isn't.
-          while (!(b & (ourPawns | theirPawns)))
-              Us == WHITE ? b <<= 8 : b >>= 8;
-
-          // The friendly pawn needs to be at least two ranks closer than the
-          // enemy pawn in order to help the potentially backward pawn advance.
-          backward = (b | (Us == WHITE ? b << 8 : b >> 8)) & theirPawns;
-      }
-
-      assert(opposed | passed | (attack_span_mask(Us, s) & theirPawns));
-
-      // A not passed pawn is a candidate to become passed if it is free to
-      // advance and if the number of friendly pawns beside or behind this
-      // pawn on adjacent files is higher or equal than the number of
-      // enemy pawns in the forward direction on the adjacent files.
-      candidate =   !(opposed | passed | backward | isolated)
-                 && (b = attack_span_mask(Them, s + pawn_push(Us)) & ourPawns) != 0
-                 &&  popcount<Max15>(b) >= popcount<Max15>(attack_span_mask(Us, s) & theirPawns);
-
-      // Passed pawns will be properly scored in evaluation because we need
-      // full attack info to evaluate passed pawns. Only the frontmost passed
-      // pawn on each file is considered a true passed pawn.
-      if (passed && !doubled)
-          e->passedPawns[Us] |= s;
-
-      // Score this pawn
-      if (isolated)
-          value -= IsolatedPawnPenalty[opposed][f];
-
-      if (doubled)
-          value -= DoubledPawnPenalty[opposed][f];
-
-      if (backward)
-          value -= BackwardPawnPenalty[opposed][f];
-
-      if (chain)
-          value += ChainBonus[f];
-
-      if (candidate)
-          value += CandidateBonus[relative_rank(Us, s)];
-  }
-
-  return value;
-}
-
-
-/// PawnEntry::shelter_storm() calculates shelter and storm penalties for the file
+/// Entry::shelter_storm() calculates shelter and storm penalties for the file
 /// the king is on, as well as the two adjacent files.
 
 template<Color Us>
-Value PawnEntry::shelter_storm(const Position& pos, Square ksq) {
+Value Entry::shelter_storm(const Position& pos, Square ksq) {
 
   const Color Them = (Us == WHITE ? BLACK : WHITE);
+  static const Bitboard MiddleEdges = (FileABB | FileHBB) & (Rank2BB | Rank3BB);
 
   Value safety = MaxSafetyBonus;
-  Bitboard b = pos.pieces(PAWN) & (in_front_bb(Us, ksq) | rank_bb(ksq));
-  Bitboard ourPawns = b & pos.pieces(Us) & ~rank_bb(ksq);
+  Bitboard b = pos.pieces(PAWN) & (in_front_bb(Us, rank_of(ksq)) | rank_bb(ksq));
+  Bitboard ourPawns = b & pos.pieces(Us);
   Bitboard theirPawns = b & pos.pieces(Them);
   Rank rkUs, rkThem;
-  File kf = file_of(ksq);
+  File kf = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
 
-  kf = (kf == FILE_A) ? kf++ : (kf == FILE_H) ? kf-- : kf;
-
-  for (int f = kf - 1; f <= kf + 1; f++)
+  for (File f = kf - File(1); f <= kf + File(1); ++f)
   {
-      // Shelter penalty is higher for the pawn in front of the king
-      b = ourPawns & FileBB[f];
-      rkUs = b ? rank_of(Us == WHITE ? lsb(b) : ~msb(b)) : RANK_1;
-      safety -= ShelterWeakness[f != kf][rkUs];
+      b = ourPawns & file_bb(f);
+      rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1;
 
-      // Storm danger is smaller if enemy pawn is blocked
-      b  = theirPawns & FileBB[f];
-      rkThem = b ? rank_of(Us == WHITE ? lsb(b) : ~msb(b)) : RANK_1;
-      safety -= StormDanger[rkThem == rkUs + 1][rkThem];
+      b  = theirPawns & file_bb(f);
+      rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
+
+      if (   (MiddleEdges & make_square(f, rkThem))
+          && file_of(ksq) == f
+          && relative_rank(Us, ksq) == rkThem - 1)
+          safety += 200;
+      else
+          safety -= ShelterWeakness[rkUs]
+                  + StormDanger[rkUs == RANK_1 ? 0 : rkThem == rkUs + 1 ? 2 : 1][rkThem];
   }
 
   return safety;
 }
 
 
-/// PawnEntry::update_safety() calculates and caches a bonus for king safety. It is
-/// called only when king square changes, about 20% of total king_safety() calls.
+/// 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 PawnEntry::update_safety(const Position& pos, Square ksq) {
+Score Entry::do_king_safety(const Position& pos, Square ksq) {
 
   kingSquares[Us] = ksq;
-  castleRights[Us] = pos.can_castle(Us);
+  castlingRights[Us] = pos.can_castle(Us);
   minKPdistance[Us] = 0;
 
   Bitboard pawns = pos.pieces(Us, PAWN);
@@ -268,20 +295,22 @@ Score PawnEntry::update_safety(const Position& pos, Square ksq) {
       while (!(DistanceRingsBB[ksq][minKPdistance[Us]++] & pawns)) {}
 
   if (relative_rank(Us, ksq) > RANK_4)
-      return kingSafety[Us] = make_score(0, -16 * minKPdistance[Us]);
+      return make_score(0, -16 * minKPdistance[Us]);
 
   Value bonus = shelter_storm<Us>(pos, ksq);
 
-  // If we can castle use the bonus after the castle if is bigger
-  if (pos.can_castle(make_castle_right(Us, KING_SIDE)))
+  // If we can castle use the bonus after the castling if it is bigger
+  if (pos.can_castle(MakeCastling<Us, KING_SIDE>::right))
       bonus = std::max(bonus, shelter_storm<Us>(pos, relative_square(Us, SQ_G1)));
 
-  if (pos.can_castle(make_castle_right(Us, QUEEN_SIDE)))
+  if (pos.can_castle(MakeCastling<Us, QUEEN_SIDE>::right))
       bonus = std::max(bonus, shelter_storm<Us>(pos, relative_square(Us, SQ_C1)));
 
-  return kingSafety[Us] = make_score(bonus, -16 * minKPdistance[Us]);
+  return make_score(bonus, -16 * minKPdistance[Us]);
 }
 
 // Explicit template instantiation
-template Score PawnEntry::update_safety<WHITE>(const Position& pos, Square ksq);
-template Score PawnEntry::update_safety<BLACK>(const Position& pos, Square ksq);
+template Score Entry::do_king_safety<WHITE>(const Position& pos, Square ksq);
+template Score Entry::do_king_safety<BLACK>(const Position& pos, Square ksq);
+
+} // namespace Pawns

src/pawns.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,99 +17,68 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(PAWNS_H_INCLUDED)
+#ifndef PAWNS_H_INCLUDED
 #define PAWNS_H_INCLUDED
 
 #include "misc.h"
 #include "position.h"
 #include "types.h"
 
-const int PawnTableSize = 16384;
+namespace Pawns {
 
-/// PawnEntry is a class which contains various information about a pawn
-/// structure. Currently, it only includes a middle game and an end game
-/// pawn structure evaluation, and a bitboard of passed pawns. We may want
-/// to add further information in the future. A lookup to the pawn hash
-/// table (performed by calling the probe method in a PawnTable object)
-/// returns a pointer to a PawnEntry object.
+/// 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.
 
-class PawnEntry {
+struct Entry {
 
-  friend struct PawnTable;
+  Score pawns_value() const { return value; }
+  Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; }
+  Bitboard passed_pawns(Color c) const { return passedPawns[c]; }
+  Bitboard candidate_pawns(Color c) const { return candidatePawns[c]; }
 
-public:
-  Score pawns_value() const;
-  Bitboard pawn_attacks(Color c) const;
-  Bitboard passed_pawns(Color c) const;
-  int file_is_half_open(Color c, File f) const;
-  int has_open_file_to_left(Color c, File f) const;
-  int has_open_file_to_right(Color c, File f) const;
+  int semiopen_file(Color c, File f) const {
+    return semiopenFiles[c] & (1 << f);
+  }
+
+  int semiopen_side(Color c, File f, bool leftSide) const {
+    return semiopenFiles[c] & (leftSide ? (1 << f) - 1 : ~((1 << (f + 1)) - 1));
+  }
+
+  int pawns_on_same_color_squares(Color c, Square s) const {
+    return pawnsOnSquares[c][!!(DarkSquares & s)];
+  }
 
   template<Color Us>
-  Score king_safety(const Position& pos, Square ksq);
+  Score king_safety(const Position& pos, Square ksq)  {
+    return  kingSquares[Us] == ksq && castlingRights[Us] == pos.can_castle(Us)
+          ? kingSafety[Us] : (kingSafety[Us] = do_king_safety<Us>(pos, ksq));
+  }
 
-private:
   template<Color Us>
-  Score update_safety(const Position& pos, Square ksq);
+  Score do_king_safety(const Position& pos, Square ksq);
 
   template<Color Us>
   Value shelter_storm(const Position& pos, Square ksq);
 
   Key key;
-  Bitboard passedPawns[2];
-  Bitboard pawnAttacks[2];
-  Square kingSquares[2];
-  int minKPdistance[2];
-  int castleRights[2];
   Score value;
-  int halfOpenFiles[2];
-  Score kingSafety[2];
+  Bitboard passedPawns[COLOR_NB];
+  Bitboard candidatePawns[COLOR_NB];
+  Bitboard pawnAttacks[COLOR_NB];
+  Square kingSquares[COLOR_NB];
+  Score kingSafety[COLOR_NB];
+  int minKPdistance[COLOR_NB];
+  int castlingRights[COLOR_NB];
+  int semiopenFiles[COLOR_NB];
+  int pawnsOnSquares[COLOR_NB][COLOR_NB]; // [color][light/dark squares]
 };
 
+typedef HashTable<Entry, 16384> Table;
 
-/// The PawnTable class represents a pawn hash table. The most important
-/// method is probe, which returns a pointer to a PawnEntry object.
+void init();
+Entry* probe(const Position& pos, Table& entries);
 
-struct PawnTable {
+} // namespace Pawns
 
-  PawnEntry* probe(const Position& pos);
-
-  template<Color Us>
-  static Score evaluate_pawns(const Position& pos, Bitboard ourPawns,
-                              Bitboard theirPawns, PawnEntry* e);
-
-  HashTable<PawnEntry, PawnTableSize> entries;
-};
-
-
-inline Score PawnEntry::pawns_value() const {
-  return value;
-}
-
-inline Bitboard PawnEntry::pawn_attacks(Color c) const {
-  return pawnAttacks[c];
-}
-
-inline Bitboard PawnEntry::passed_pawns(Color c) const {
-  return passedPawns[c];
-}
-
-inline int PawnEntry::file_is_half_open(Color c, File f) const {
-  return halfOpenFiles[c] & (1 << int(f));
-}
-
-inline int PawnEntry::has_open_file_to_left(Color c, File f) const {
-  return halfOpenFiles[c] & ((1 << int(f)) - 1);
-}
-
-inline int PawnEntry::has_open_file_to_right(Color c, File f) const {
-  return halfOpenFiles[c] & ~((1 << int(f+1)) - 1);
-}
-
-template<Color Us>
-inline Score PawnEntry::king_safety(const Position& pos, Square ksq) {
-  return kingSquares[Us] == ksq && castleRights[Us] == pos.can_castle(Us)
-       ? kingSafety[Us] : update_safety<Us>(pos, ksq);
-}
-
-#endif // !defined(PAWNS_H_INCLUDED)
+#endif // #ifndef PAWNS_H_INCLUDED

src/platform.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,12 +17,12 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(PLATFORM_H_INCLUDED)
+#ifndef PLATFORM_H_INCLUDED
 #define PLATFORM_H_INCLUDED
 
-#if defined(_MSC_VER)
+#ifdef _MSC_VER
 
-// Disable some silly and noisy warning from MSVC compiler
+// 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'
@@ -42,13 +42,15 @@ typedef unsigned __int64 uint64_t;
 #  include <inttypes.h>
 #endif
 
-#if !defined(_WIN32) && !defined(_WIN64) // Linux - Unix
+#ifndef _WIN32 // Linux - Unix
 
 #  include <sys/time.h>
-typedef timeval sys_time_t;
 
-inline void system_time(sys_time_t* t) { gettimeofday(t, NULL); }
-inline int64_t time_to_msec(const sys_time_t& t) { return t.tv_sec * 1000LL + t.tv_usec / 1000; }
+inline int64_t system_time_to_msec() {
+  timeval t;
+  gettimeofday(&t, NULL);
+  return t.tv_sec * 1000LL + t.tv_usec / 1000;
+}
 
 #  include <pthread.h>
 typedef pthread_mutex_t Lock;
@@ -65,18 +67,20 @@ typedef void*(*pt_start_fn)(void*);
 #  define cond_signal(x) pthread_cond_signal(&(x))
 #  define cond_wait(x,y) pthread_cond_wait(&(x),&(y))
 #  define cond_timedwait(x,y,z) pthread_cond_timedwait(&(x),&(y),z)
-#  define thread_create(x,f,t) !pthread_create(&(x),NULL,(pt_start_fn)f,t)
+#  define thread_create(x,f,t) pthread_create(&(x),NULL,(pt_start_fn)f,t)
 #  define thread_join(x) pthread_join(x, NULL)
 
 #else // Windows and MinGW
 
 #  include <sys/timeb.h>
-typedef _timeb sys_time_t;
 
-inline void system_time(sys_time_t* t) { _ftime(t); }
-inline int64_t time_to_msec(const sys_time_t& t) { return t.time * 1000LL + t.millitm; }
+inline int64_t system_time_to_msec() {
+  _timeb t;
+  _ftime(&t);
+  return t.time * 1000LL + t.millitm;
+}
 
-#if !defined(NOMINMAX)
+#ifndef NOMINMAX
 #  define NOMINMAX // disable macros min() and max()
 #endif
 
@@ -85,13 +89,16 @@ inline int64_t time_to_msec(const sys_time_t& t) { return t.time * 1000LL + t.mi
 #undef WIN32_LEAN_AND_MEAN
 #undef NOMINMAX
 
-// We use critical sections on Windows to support Windows XP and older versions,
-// unfortunatly cond_wait() is racy between lock_release() and WaitForSingleObject()
+// We use critical sections on Windows to support Windows XP and older versions.
+// Unfortunately, cond_wait() is racy between lock_release() and WaitForSingleObject()
 // but apart from this they have the same speed performance of SRW locks.
 typedef CRITICAL_SECTION Lock;
 typedef HANDLE WaitCondition;
 typedef HANDLE NativeHandle;
 
+// On Windows 95 and 98 parameter lpThreadId may not be null
+inline DWORD* dwWin9xKludge() { static DWORD dw; return &dw; }
+
 #  define lock_init(x) InitializeCriticalSection(&(x))
 #  define lock_grab(x) EnterCriticalSection(&(x))
 #  define lock_release(x) LeaveCriticalSection(&(x))
@@ -101,9 +108,9 @@ typedef HANDLE NativeHandle;
 #  define cond_signal(x) SetEvent(x)
 #  define cond_wait(x,y) { lock_release(y); WaitForSingleObject(x, INFINITE); lock_grab(y); }
 #  define cond_timedwait(x,y,z) { lock_release(y); WaitForSingleObject(x,z); lock_grab(y); }
-#  define thread_create(x,f,t) (x = CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)f,t,0,NULL), x != NULL)
+#  define thread_create(x,f,t) (x = CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)f,t,0,dwWin9xKludge()))
 #  define thread_join(x) { WaitForSingleObject(x, INFINITE); CloseHandle(x); }
 
 #endif
 
-#endif // !defined(PLATFORM_H_INCLUDED)
+#endif // #ifndef PLATFORM_H_INCLUDED

src/position.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,10 +17,11 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(POSITION_H_INCLUDED)
+#ifndef POSITION_H_INCLUDED
 #define POSITION_H_INCLUDED
 
 #include <cassert>
+#include <cstddef>
 
 #include "bitboard.h"
 #include "types.h"
@@ -29,7 +30,7 @@
 /// The checkInfo struct is initialized at c'tor time and keeps info used
 /// to detect if a move gives check.
 class Position;
-class Thread;
+struct Thread;
 
 struct CheckInfo {
 
@@ -37,21 +38,21 @@ struct CheckInfo {
 
   Bitboard dcCandidates;
   Bitboard pinned;
-  Bitboard checkSq[8];
+  Bitboard checkSq[PIECE_TYPE_NB];
   Square ksq;
 };
 
 
-/// The StateInfo struct stores information we need to restore a Position
+/// The 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), an StateInfo object
-/// must be passed as a parameter.
+/// is made on the board (by calling Position::do_move), a StateInfo
+/// object must be passed as a parameter.
 
 struct StateInfo {
   Key pawnKey, materialKey;
-  Value npMaterial[2];
-  int castleRights, rule50, pliesFromNull;
-  Score psqScore;
+  Value npMaterial[COLOR_NB];
+  int castlingRights, rule50, pliesFromNull;
+  Score psq;
   Square epSquare;
 
   Key key;
@@ -60,48 +61,29 @@ struct StateInfo {
   StateInfo* previous;
 };
 
-struct ReducedStateInfo {
-  Key pawnKey, materialKey;
-  Value npMaterial[2];
-  int castleRights, rule50, pliesFromNull;
-  Score psqScore;
-  Square epSquare;
-};
+
+/// When making a move the current StateInfo up to 'key' excluded is copied to
+/// the new one. Here we calculate the quad words (64bits) needed to be copied.
+const size_t StateCopySize64 = offsetof(StateInfo, key) / sizeof(uint64_t) + 1;
 
 
-/// The position data structure. A position consists of the following data:
-///
-///    * For each piece type, a bitboard representing the squares occupied
-///      by pieces of that type.
-///    * For each color, a bitboard representing the squares occupied by
-///      pieces of that color.
-///    * A bitboard of all occupied squares.
-///    * A bitboard of all checking pieces.
-///    * A 64-entry array of pieces, indexed by the squares of the board.
-///    * The current side to move.
-///    * Information about the castling rights for both sides.
-///    * The initial files of the kings and both pairs of rooks. This is
-///      used to implement the Chess960 castling rules.
-///    * The en passant square (which is SQ_NONE if no en passant capture is
-///      possible).
-///    * The squares of the kings for both sides.
-///    * Hash keys for the position itself, the current pawn structure, and
-///      the current material situation.
-///    * Hash keys for all previous positions in the game for detecting
-///      repetition draws.
-///    * A counter for detecting 50 move rule draws.
+/// The Position class stores the information regarding the board representation
+/// like pieces, side to move, hash keys, castling info, etc. The most important
+/// methods are do_move() and undo_move(), used by the search to update node info
+/// when traversing the search tree.
 
 class Position {
 public:
   Position() {}
-  Position(const Position& p, Thread* t) { *this = p; thisThread = t; }
-  Position(const std::string& f, bool c960, Thread* t) { from_fen(f, c960, t); }
+  Position(const Position& pos, Thread* t) { *this = pos; thisThread = t; }
+  Position(const std::string& f, bool c960, Thread* t) { set(f, c960, t); }
   Position& operator=(const Position&);
+  static void init();
 
   // Text input/output
-  void from_fen(const std::string& fen, bool isChess960, Thread* th);
-  const std::string to_fen() const;
-  void print(Move m = MOVE_NONE) const;
+  void set(const std::string& fenStr, bool isChess960, Thread* th);
+  const std::string fen() const;
+  const std::string pretty(Move m = MOVE_NONE) const;
 
   // Position representation
   Bitboard pieces() const;
@@ -113,57 +95,54 @@ public:
   Piece piece_on(Square s) const;
   Square king_square(Color c) const;
   Square ep_square() const;
-  bool is_empty(Square s) const;
-  const Square* piece_list(Color c, PieceType pt) const;
-  int piece_count(Color c, PieceType pt) const;
+  bool empty(Square s) const;
+  template<PieceType Pt> int count(Color c) const;
+  template<PieceType Pt> const Square* list(Color c) const;
 
   // Castling
-  int can_castle(CastleRight f) const;
   int can_castle(Color c) const;
-  bool castle_impeded(Color c, CastlingSide s) const;
-  Square castle_rook_square(Color c, CastlingSide s) const;
+  int can_castle(CastlingRight cr) const;
+  bool castling_impeded(CastlingRight cr) const;
+  Square castling_rook_square(CastlingRight cr) const;
 
   // Checking
-  bool in_check() const;
   Bitboard checkers() const;
   Bitboard discovered_check_candidates() const;
-  Bitboard pinned_pieces() const;
+  Bitboard pinned_pieces(Color c) const;
 
   // Attacks to/from a given square
   Bitboard attackers_to(Square s) const;
   Bitboard attackers_to(Square s, Bitboard occ) const;
-  Bitboard attacks_from(Piece p, Square s) const;
-  static Bitboard attacks_from(Piece p, Square s, Bitboard occ);
+  Bitboard attacks_from(Piece pc, Square s) const;
   template<PieceType> Bitboard attacks_from(Square s) const;
   template<PieceType> Bitboard attacks_from(Square s, Color c) const;
 
   // Properties of moves
-  bool move_gives_check(Move m, const CheckInfo& ci) const;
-  bool move_attacks_square(Move m, Square s) const;
-  bool move_is_legal(const Move m) const;
-  bool pl_move_is_legal(Move m, Bitboard pinned) const;
-  bool is_pseudo_legal(const Move m) const;
-  bool is_capture(Move m) const;
-  bool is_capture_or_promotion(Move m) const;
-  bool is_passed_pawn_push(Move m) const;
-  Piece piece_moved(Move m) const;
+  bool legal(Move m, Bitboard pinned) const;
+  bool pseudo_legal(const Move m) const;
+  bool capture(Move m) const;
+  bool capture_or_promotion(Move m) const;
+  bool gives_check(Move m, const CheckInfo& ci) const;
+  bool advanced_pawn_push(Move m) const;
+  Piece moved_piece(Move m) const;
   PieceType captured_piece_type() const;
 
   // Piece specific
-  bool pawn_is_passed(Color c, Square s) const;
+  bool pawn_passed(Color c, Square s) const;
   bool pawn_on_7th(Color c) const;
-  bool opposite_bishops() const;
   bool bishop_pair(Color c) const;
+  bool opposite_bishops() const;
 
   // Doing and undoing moves
   void do_move(Move m, StateInfo& st);
   void do_move(Move m, StateInfo& st, const CheckInfo& ci, bool moveIsCheck);
   void undo_move(Move m);
-  template<bool Do> void do_null_move(StateInfo& st);
+  void do_null_move(StateInfo& st);
+  void undo_null_move();
 
   // Static exchange evaluation
-  int see(Move m) const;
-  int see_sign(Move m) const;
+  Value see(Move m) const;
+  Value see_sign(Move m) const;
 
   // Accessing hash keys
   Key key() const;
@@ -173,67 +152,61 @@ public:
 
   // Incremental piece-square evaluation
   Score psq_score() const;
-  Score psq_delta(Piece p, Square from, Square to) const;
   Value non_pawn_material(Color c) const;
 
   // Other properties of the position
   Color side_to_move() const;
-  int startpos_ply_counter() const;
+  int game_ply() const;
   bool is_chess960() const;
   Thread* this_thread() const;
-  int64_t nodes_searched() const;
-  void set_nodes_searched(int64_t n);
-  template<bool SkipRepetition> bool is_draw() const;
+  uint64_t nodes_searched() const;
+  void set_nodes_searched(uint64_t n);
+  bool is_draw() const;
 
   // Position consistency check, for debugging
-  bool pos_is_ok(int* failedStep = NULL) const;
+  bool pos_is_ok(int* step = NULL) const;
   void flip();
 
 private:
   // Initialization helpers (used while setting up a position)
   void clear();
-  void put_piece(Piece p, Square s);
-  void set_castle_right(Color c, Square rfrom);
+  void set_castling_right(Color c, Square rfrom);
+  void set_state(StateInfo* si) const;
 
-  // Helper template functions
-  template<bool Do> void do_castle_move(Move m);
-  template<bool FindPinned> Bitboard hidden_checkers() const;
-
-  // Computing hash keys from scratch (for initialization and debugging)
-  Key compute_key() const;
-  Key compute_pawn_key() const;
-  Key compute_material_key() const;
-
-  // Computing incremental evaluation scores and material counts
-  Score compute_psq_score() const;
-  Value compute_non_pawn_material(Color c) const;
+  // Helper functions
+  Bitboard check_blockers(Color c, Color kingColor) const;
+  void put_piece(Square s, Color c, PieceType pt);
+  void remove_piece(Square s, Color c, PieceType pt);
+  void move_piece(Square from, Square to, Color c, PieceType pt);
+  template<bool Do>
+  void do_castling(Square from, Square& to, Square& rfrom, Square& rto);
 
   // Board and pieces
-  Piece board[64];             // [square]
-  Bitboard byTypeBB[8];        // [pieceType]
-  Bitboard byColorBB[2];       // [color]
-  int pieceCount[2][8];        // [color][pieceType]
-  Square pieceList[2][8][16];  // [color][pieceType][index]
-  int index[64];               // [square]
+  Piece board[SQUARE_NB];
+  Bitboard byTypeBB[PIECE_TYPE_NB];
+  Bitboard byColorBB[COLOR_NB];
+  int pieceCount[COLOR_NB][PIECE_TYPE_NB];
+  Square pieceList[COLOR_NB][PIECE_TYPE_NB][16];
+  int index[SQUARE_NB];
 
   // Other info
-  int castleRightsMask[64];      // [square]
-  Square castleRookSquare[2][2]; // [color][side]
-  Bitboard castlePath[2][2];     // [color][side]
+  int castlingRightsMask[SQUARE_NB];
+  Square castlingRookSquare[CASTLING_RIGHT_NB];
+  Bitboard castlingPath[CASTLING_RIGHT_NB];
   StateInfo startState;
-  int64_t nodes;
-  int startPosPly;
+  uint64_t nodes;
+  int gamePly;
   Color sideToMove;
   Thread* thisThread;
   StateInfo* st;
-  int chess960;
+  bool chess960;
 };
 
-inline int64_t Position::nodes_searched() const {
+inline uint64_t Position::nodes_searched() const {
   return nodes;
 }
 
-inline void Position::set_nodes_searched(int64_t n) {
+inline void Position::set_nodes_searched(uint64_t n) {
   nodes = n;
 }
 
@@ -241,11 +214,11 @@ inline Piece Position::piece_on(Square s) const {
   return board[s];
 }
 
-inline Piece Position::piece_moved(Move m) const {
+inline Piece Position::moved_piece(Move m) const {
   return board[from_sq(m)];
 }
 
-inline bool Position::is_empty(Square s) const {
+inline bool Position::empty(Square s) const {
   return board[s] == NO_PIECE;
 }
 
@@ -277,12 +250,12 @@ inline Bitboard Position::pieces(Color c, PieceType pt1, PieceType pt2) const {
   return byColorBB[c] & (byTypeBB[pt1] | byTypeBB[pt2]);
 }
 
-inline int Position::piece_count(Color c, PieceType pt) const {
-  return pieceCount[c][pt];
+template<PieceType Pt> inline int Position::count(Color c) const {
+  return pieceCount[c][Pt];
 }
 
-inline const Square* Position::piece_list(Color c, PieceType pt) const {
-  return pieceList[c][pt];
+template<PieceType Pt> inline const Square* Position::list(Color c) const {
+  return pieceList[c][Pt];
 }
 
 inline Square Position::ep_square() const {
@@ -293,26 +266,26 @@ inline Square Position::king_square(Color c) const {
   return pieceList[c][KING][0];
 }
 
-inline int Position::can_castle(CastleRight f) const {
-  return st->castleRights & f;
+inline int Position::can_castle(CastlingRight cr) const {
+  return st->castlingRights & cr;
 }
 
 inline int Position::can_castle(Color c) const {
-  return st->castleRights & ((WHITE_OO | WHITE_OOO) << (2 * c));
+  return st->castlingRights & ((WHITE_OO | WHITE_OOO) << (2 * c));
 }
 
-inline bool Position::castle_impeded(Color c, CastlingSide s) const {
-  return byTypeBB[ALL_PIECES] & castlePath[c][s];
+inline bool Position::castling_impeded(CastlingRight cr) const {
+  return byTypeBB[ALL_PIECES] & castlingPath[cr];
 }
 
-inline Square Position::castle_rook_square(Color c, CastlingSide s) const {
-  return castleRookSquare[c][s];
+inline Square Position::castling_rook_square(CastlingRight cr) const {
+  return castlingRookSquare[cr];
 }
 
 template<PieceType Pt>
 inline Bitboard Position::attacks_from(Square s) const {
 
-  return  Pt == BISHOP || Pt == ROOK ? attacks_bb<Pt>(s, pieces())
+  return  Pt == BISHOP || Pt == ROOK ? attacks_bb<Pt>(s, byTypeBB[ALL_PIECES])
         : Pt == QUEEN  ? attacks_from<ROOK>(s) | attacks_from<BISHOP>(s)
         : StepAttacksBB[Pt][s];
 }
@@ -322,8 +295,8 @@ inline Bitboard Position::attacks_from<PAWN>(Square s, Color c) const {
   return StepAttacksBB[make_piece(c, PAWN)][s];
 }
 
-inline Bitboard Position::attacks_from(Piece p, Square s) const {
-  return attacks_from(p, s, byTypeBB[ALL_PIECES]);
+inline Bitboard Position::attacks_from(Piece pc, Square s) const {
+  return attacks_bb(pc, s, byTypeBB[ALL_PIECES]);
 }
 
 inline Bitboard Position::attackers_to(Square s) const {
@@ -334,30 +307,27 @@ inline Bitboard Position::checkers() const {
   return st->checkersBB;
 }
 
-inline bool Position::in_check() const {
-  return st->checkersBB != 0;
-}
-
 inline Bitboard Position::discovered_check_candidates() const {
-  return hidden_checkers<false>();
+  return check_blockers(sideToMove, ~sideToMove);
 }
 
-inline Bitboard Position::pinned_pieces() const {
-  return hidden_checkers<true>();
+inline Bitboard Position::pinned_pieces(Color c) const {
+  return check_blockers(c, c);
 }
 
-inline bool Position::pawn_is_passed(Color c, Square s) const {
+inline bool Position::pawn_passed(Color c, Square s) const {
   return !(pieces(~c, PAWN) & passed_pawn_mask(c, s));
 }
 
+inline bool Position::advanced_pawn_push(Move m) const {
+  return   type_of(moved_piece(m)) == PAWN
+        && relative_rank(sideToMove, from_sq(m)) > RANK_4;
+}
+
 inline Key Position::key() const {
   return st->key;
 }
 
-inline Key Position::exclusion_key() const {
-  return st->key ^ Zobrist::exclusion;
-}
-
 inline Key Position::pawn_key() const {
   return st->pawnKey;
 }
@@ -366,26 +336,16 @@ inline Key Position::material_key() const {
   return st->materialKey;
 }
 
-inline Score Position::psq_delta(Piece p, Square from, Square to) const {
-  return pieceSquareTable[p][to] - pieceSquareTable[p][from];
-}
-
 inline Score Position::psq_score() const {
-  return st->psqScore;
+  return st->psq;
 }
 
 inline Value Position::non_pawn_material(Color c) const {
   return st->npMaterial[c];
 }
 
-inline bool Position::is_passed_pawn_push(Move m) const {
-
-  return   type_of(piece_moved(m)) == PAWN
-        && pawn_is_passed(sideToMove, to_sq(m));
-}
-
-inline int Position::startpos_ply_counter() const {
-  return startPosPly + st->pliesFromNull; // HACK
+inline int Position::game_ply() const {
+  return gamePly;
 }
 
 inline bool Position::opposite_bishops() const {
@@ -409,17 +369,17 @@ inline bool Position::is_chess960() const {
   return chess960;
 }
 
-inline bool Position::is_capture_or_promotion(Move m) const {
+inline bool Position::capture_or_promotion(Move m) const {
 
   assert(is_ok(m));
-  return type_of(m) ? type_of(m) != CASTLE : !is_empty(to_sq(m));
+  return type_of(m) != NORMAL ? type_of(m) != CASTLING : !empty(to_sq(m));
 }
 
-inline bool Position::is_capture(Move m) const {
+inline bool Position::capture(Move m) const {
 
-  // Note that castle is coded as "king captures the rook"
+  // Note that castling is encoded as "king captures the rook"
   assert(is_ok(m));
-  return (!is_empty(to_sq(m)) && type_of(m) != CASTLE) || type_of(m) == ENPASSANT;
+  return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == ENPASSANT;
 }
 
 inline PieceType Position::captured_piece_type() const {
@@ -430,4 +390,44 @@ inline Thread* Position::this_thread() const {
   return thisThread;
 }
 
-#endif // !defined(POSITION_H_INCLUDED)
+inline void Position::put_piece(Square s, Color c, PieceType pt) {
+
+  board[s] = make_piece(c, pt);
+  byTypeBB[ALL_PIECES] |= s;
+  byTypeBB[pt] |= s;
+  byColorBB[c] |= s;
+  index[s] = pieceCount[c][pt]++;
+  pieceList[c][pt][index[s]] = s;
+}
+
+inline void Position::move_piece(Square from, Square to, Color c, PieceType pt) {
+
+  // index[from] is not updated and becomes stale. This works as long
+  // as index[] is accessed just by known occupied squares.
+  Bitboard from_to_bb = SquareBB[from] ^ SquareBB[to];
+  byTypeBB[ALL_PIECES] ^= from_to_bb;
+  byTypeBB[pt] ^= from_to_bb;
+  byColorBB[c] ^= from_to_bb;
+  board[from] = NO_PIECE;
+  board[to] = make_piece(c, pt);
+  index[to] = index[from];
+  pieceList[c][pt][index[to]] = to;
+}
+
+inline void Position::remove_piece(Square s, Color c, PieceType pt) {
+
+  // WARNING: This is not a reversible operation. If we remove a piece in
+  // do_move() and then replace it in undo_move() we will put it at the end of
+  // the list and not in its original place, it means index[] and pieceList[]
+  // are not guaranteed to be invariant to a do_move() + undo_move() sequence.
+  byTypeBB[ALL_PIECES] ^= s;
+  byTypeBB[pt] ^= s;
+  byColorBB[c] ^= s;
+  /* board[s] = NO_PIECE; */ // Not needed, will be overwritten by capturing
+  Square lastSquare = pieceList[c][pt][--pieceCount[c][pt]];
+  index[lastSquare] = index[s];
+  pieceList[c][pt][index[lastSquare]] = lastSquare;
+  pieceList[c][pt][pieceCount[c][pt]] = SQ_NONE;
+}
+
+#endif // #ifndef POSITION_H_INCLUDED

src/psqtab.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(PSQTAB_H_INCLUDED)
+#ifndef PSQTAB_H_INCLUDED
 #define PSQTAB_H_INCLUDED
 
 #include "types.h"
@@ -26,73 +26,73 @@
 
 
 /// PSQT[PieceType][Square] contains Piece-Square scores. For each piece type on
-/// a given square a (midgame, endgame) score pair is assigned. PSQT is defined
-/// for white side, for black side the tables are symmetric.
+/// a given square a (middlegame, endgame) score pair is assigned. PSQT is defined
+/// for the white side and the tables are symmetric for the black side.
 
-static const Score PSQT[][64] = {
+static const Score PSQT[][SQUARE_NB] = {
   { },
   { // Pawn
    S(  0, 0), S( 0, 0), S( 0, 0), S( 0, 0), S(0,  0), S( 0, 0), S( 0, 0), S(  0, 0),
-   S(-28,-8), S(-6,-8), S( 4,-8), S(14,-8), S(14,-8), S( 4,-8), S(-6,-8), S(-28,-8),
-   S(-28,-8), S(-6,-8), S( 9,-8), S(36,-8), S(36,-8), S( 9,-8), S(-6,-8), S(-28,-8),
-   S(-28,-8), S(-6,-8), S(17,-8), S(58,-8), S(58,-8), S(17,-8), S(-6,-8), S(-28,-8),
-   S(-28,-8), S(-6,-8), S(17,-8), S(36,-8), S(36,-8), S(17,-8), S(-6,-8), S(-28,-8),
-   S(-28,-8), S(-6,-8), S( 9,-8), S(14,-8), S(14,-8), S( 9,-8), S(-6,-8), S(-28,-8),
-   S(-28,-8), S(-6,-8), S( 4,-8), S(14,-8), S(14,-8), S( 4,-8), S(-6,-8), S(-28,-8),
+   S(-20, 0), S( 0, 0), S( 0, 0), S( 0, 0), S(0,  0), S( 0, 0), S( 0, 0), S(-20, 0),
+   S(-20, 0), S( 0, 0), S(10, 0), S(20, 0), S(20, 0), S(10, 0), S( 0, 0), S(-20, 0),
+   S(-20, 0), S( 0, 0), S(20, 0), S(40, 0), S(40, 0), S(20, 0), S( 0, 0), S(-20, 0),
+   S(-20, 0), S( 0, 0), S(10, 0), S(20, 0), S(20, 0), S(10, 0), S( 0, 0), S(-20, 0),
+   S(-20, 0), S( 0, 0), S( 0, 0), S( 0, 0), S(0,  0), S( 0, 0), S( 0, 0), S(-20, 0),
+   S(-20, 0), S( 0, 0), S( 0, 0), S( 0, 0), S(0,  0), S( 0, 0), S( 0, 0), S(-20, 0),
    S(  0, 0), S( 0, 0), S( 0, 0), S( 0, 0), S(0,  0), S( 0, 0), S( 0, 0), S(  0, 0)
   },
   { // Knight
-   S(-135,-104), S(-107,-79), S(-80,-55), S(-67,-42), S(-67,-42), S(-80,-55), S(-107,-79), S(-135,-104),
-   S( -93, -79), S( -67,-55), S(-39,-30), S(-25,-17), S(-25,-17), S(-39,-30), S( -67,-55), S( -93, -79),
-   S( -53, -55), S( -25,-30), S(  1, -6), S( 13,  5), S( 13,  5), S(  1, -6), S( -25,-30), S( -53, -55),
-   S( -25, -42), S(   1,-17), S( 27,  5), S( 41, 18), S( 41, 18), S( 27,  5), S(   1,-17), S( -25, -42),
-   S( -11, -42), S(  13,-17), S( 41,  5), S( 55, 18), S( 55, 18), S( 41,  5), S(  13,-17), S( -11, -42),
-   S( -11, -55), S(  13,-30), S( 41, -6), S( 55,  5), S( 55,  5), S( 41, -6), S(  13,-30), S( -11, -55),
-   S( -53, -79), S( -25,-55), S(  1,-30), S( 13,-17), S( 13,-17), S(  1,-30), S( -25,-55), S( -53, -79),
-   S(-193,-104), S( -67,-79), S(-39,-55), S(-25,-42), S(-25,-42), S(-39,-55), S( -67,-79), S(-193,-104)
+   S(-144,-98), S(-109,-83), S(-85,-51), S(-73,-16), S(-73,-16), S(-85,-51), S(-109,-83), S(-144,-98),
+   S( -88,-68), S( -43,-53), S(-19,-21), S( -7, 14), S( -7, 14), S(-19,-21), S( -43,-53), S( -88,-68),
+   S( -69,-53), S( -24,-38), S(  0, -6), S( 12, 29), S( 12, 29), S(  0, -6), S( -24,-38), S( -69,-53),
+   S( -28,-42), S(  17,-27), S( 41,  5), S( 53, 40), S( 53, 40), S( 41,  5), S(  17,-27), S( -28,-42),
+   S( -30,-42), S(  15,-27), S( 39,  5), S( 51, 40), S( 51, 40), S( 39,  5), S(  15,-27), S( -30,-42),
+   S( -10,-53), S(  35,-38), S( 59, -6), S( 71, 29), S( 71, 29), S( 59, -6), S(  35,-38), S( -10,-53),
+   S( -64,-68), S( -19,-53), S(  5,-21), S( 17, 14), S( 17, 14), S(  5,-21), S( -19,-53), S( -64,-68),
+   S(-200,-98), S( -65,-83), S(-41,-51), S(-29,-16), S(-29,-16), S(-41,-51), S( -65,-83), S(-200,-98)
   },
   { // Bishop
-   S(-40,-59), S(-40,-42), S(-35,-35), S(-30,-26), S(-30,-26), S(-35,-35), S(-40,-42), S(-40,-59),
-   S(-17,-42), S(  0,-26), S( -4,-18), S(  0,-11), S(  0,-11), S( -4,-18), S(  0,-26), S(-17,-42),
-   S(-13,-35), S( -4,-18), S(  8,-11), S(  4, -4), S(  4, -4), S(  8,-11), S( -4,-18), S(-13,-35),
-   S( -8,-26), S(  0,-11), S(  4, -4), S( 17,  4), S( 17,  4), S(  4, -4), S(  0,-11), S( -8,-26),
-   S( -8,-26), S(  0,-11), S(  4, -4), S( 17,  4), S( 17,  4), S(  4, -4), S(  0,-11), S( -8,-26),
-   S(-13,-35), S( -4,-18), S(  8,-11), S(  4, -4), S(  4, -4), S(  8,-11), S( -4,-18), S(-13,-35),
-   S(-17,-42), S(  0,-26), S( -4,-18), S(  0,-11), S(  0,-11), S( -4,-18), S(  0,-26), S(-17,-42),
-   S(-17,-59), S(-17,-42), S(-13,-35), S( -8,-26), S( -8,-26), S(-13,-35), S(-17,-42), S(-17,-59)
+   S(-54,-65), S(-27,-42), S(-34,-44), S(-43,-26), S(-43,-26), S(-34,-44), S(-27,-42), S(-54,-65),
+   S(-29,-43), S(  8,-20), S(  1,-22), S( -8, -4), S( -8, -4), S(  1,-22), S(  8,-20), S(-29,-43),
+   S(-20,-33), S( 17,-10), S( 10,-12), S(  1,  6), S(  1,  6), S( 10,-12), S( 17,-10), S(-20,-33),
+   S(-19,-35), S( 18,-12), S( 11,-14), S(  2,  4), S(  2,  4), S( 11,-14), S( 18,-12), S(-19,-35),
+   S(-22,-35), S( 15,-12), S(  8,-14), S( -1,  4), S( -1,  4), S(  8,-14), S( 15,-12), S(-22,-35),
+   S(-28,-33), S(  9,-10), S(  2,-12), S( -7,  6), S( -7,  6), S(  2,-12), S(  9,-10), S(-28,-33),
+   S(-32,-43), S(  5,-20), S( -2,-22), S(-11, -4), S(-11, -4), S( -2,-22), S(  5,-20), S(-32,-43),
+   S(-49,-65), S(-22,-42), S(-29,-44), S(-38,-26), S(-38,-26), S(-29,-44), S(-22,-42), S(-49,-65)
   },
   { // Rook
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3),
-   S(-12, 3), S(-7, 3), S(-2, 3), S(2, 3), S(2, 3), S(-2, 3), S(-7, 3), S(-12, 3)
+   S(-22, 3), S(-17, 3), S(-12, 3), S(-8, 3), S(-8, 3), S(-12, 3), S(-17, 3), S(-22, 3),
+   S(-22, 3), S( -7, 3), S( -2, 3), S( 2, 3), S( 2, 3), S( -2, 3), S( -7, 3), S(-22, 3),
+   S(-22, 3), S( -7, 3), S( -2, 3), S( 2, 3), S( 2, 3), S( -2, 3), S( -7, 3), S(-22, 3),
+   S(-22, 3), S( -7, 3), S( -2, 3), S( 2, 3), S( 2, 3), S( -2, 3), S( -7, 3), S(-22, 3),
+   S(-22, 3), S( -7, 3), S( -2, 3), S( 2, 3), S( 2, 3), S( -2, 3), S( -7, 3), S(-22, 3),
+   S(-22, 3), S( -7, 3), S( -2, 3), S( 2, 3), S( 2, 3), S( -2, 3), S( -7, 3), S(-22, 3),
+   S(-11, 3), S(  4, 3), S(  9, 3), S(13, 3), S(13, 3), S(  9, 3), S(  4, 3), S(-11, 3),
+   S(-22, 3), S(-17, 3), S(-12, 3), S(-8, 3), S(-8, 3), S(-12, 3), S(-17, 3), S(-22, 3)
   },
   { // Queen
-   S(8,-80), S(8,-54), S(8,-42), S(8,-30), S(8,-30), S(8,-42), S(8,-54), S(8,-80),
-   S(8,-54), S(8,-30), S(8,-18), S(8, -6), S(8, -6), S(8,-18), S(8,-30), S(8,-54),
-   S(8,-42), S(8,-18), S(8, -6), S(8,  6), S(8,  6), S(8, -6), S(8,-18), S(8,-42),
-   S(8,-30), S(8, -6), S(8,  6), S(8, 18), S(8, 18), S(8,  6), S(8, -6), S(8,-30),
-   S(8,-30), S(8, -6), S(8,  6), S(8, 18), S(8, 18), S(8,  6), S(8, -6), S(8,-30),
-   S(8,-42), S(8,-18), S(8, -6), S(8,  6), S(8,  6), S(8, -6), S(8,-18), S(8,-42),
-   S(8,-54), S(8,-30), S(8,-18), S(8, -6), S(8, -6), S(8,-18), S(8,-30), S(8,-54),
-   S(8,-80), S(8,-54), S(8,-42), S(8,-30), S(8,-30), S(8,-42), S(8,-54), S(8,-80)
+   S(-2,-80), S(-2,-54), S(-2,-42), S(-2,-30), S(-2,-30), S(-2,-42), S(-2,-54), S(-2,-80),
+   S(-2,-54), S( 8,-30), S( 8,-18), S( 8, -6), S( 8, -6), S( 8,-18), S( 8,-30), S(-2,-54),
+   S(-2,-42), S( 8,-18), S( 8, -6), S( 8,  6), S( 8,  6), S( 8, -6), S( 8,-18), S(-2,-42),
+   S(-2,-30), S( 8, -6), S( 8,  6), S( 8, 18), S( 8, 18), S( 8,  6), S( 8, -6), S(-2,-30),
+   S(-2,-30), S( 8, -6), S( 8,  6), S( 8, 18), S( 8, 18), S( 8,  6), S( 8, -6), S(-2,-30),
+   S(-2,-42), S( 8,-18), S( 8, -6), S( 8,  6), S( 8,  6), S( 8, -6), S( 8,-18), S(-2,-42),
+   S(-2,-54), S( 8,-30), S( 8,-18), S( 8, -6), S( 8, -6), S( 8,-18), S( 8,-30), S(-2,-54),
+   S(-2,-80), S(-2,-54), S(-2,-42), S(-2,-30), S(-2,-30), S(-2,-42), S(-2,-54), S(-2,-80)
   },
   { // King
-   S(287, 18), S(311, 77), S(262,105), S(214,135), S(214,135), S(262,105), S(311, 77), S(287, 18),
-   S(262, 77), S(287,135), S(238,165), S(190,193), S(190,193), S(238,165), S(287,135), S(262, 77),
-   S(214,105), S(238,165), S(190,193), S(142,222), S(142,222), S(190,193), S(238,165), S(214,105),
-   S(190,135), S(214,193), S(167,222), S(119,251), S(119,251), S(167,222), S(214,193), S(190,135),
-   S(167,135), S(190,193), S(142,222), S( 94,251), S( 94,251), S(142,222), S(190,193), S(167,135),
-   S(142,105), S(167,165), S(119,193), S( 69,222), S( 69,222), S(119,193), S(167,165), S(142,105),
-   S(119, 77), S(142,135), S( 94,165), S( 46,193), S( 46,193), S( 94,165), S(142,135), S(119, 77),
-   S(94,  18), S(119, 77), S( 69,105), S( 21,135), S( 21,135), S( 69,105), S(119, 77), S( 94, 18)
+   S(298, 27), S(332, 81), S(273,108), S(225,116), S(225,116), S(273,108), S(332, 81), S(298, 27),
+   S(287, 74), S(321,128), S(262,155), S(214,163), S(214,163), S(262,155), S(321,128), S(287, 74),
+   S(224,111), S(258,165), S(199,192), S(151,200), S(151,200), S(199,192), S(258,165), S(224,111),
+   S(196,135), S(230,189), S(171,216), S(123,224), S(123,224), S(171,216), S(230,189), S(196,135),
+   S(173,135), S(207,189), S(148,216), S(100,224), S(100,224), S(148,216), S(207,189), S(173,135),
+   S(146,111), S(180,165), S(121,192), S( 73,200), S( 73,200), S(121,192), S(180,165), S(146,111),
+   S(119, 74), S(153,128), S( 94,155), S( 46,163), S( 46,163), S( 94,155), S(153,128), S(119, 74),
+   S( 98, 27), S(132, 81), S( 73,108), S( 25,116), S( 25,116), S( 73,108), S(132, 81), S( 98, 27)
   }
 };
 
 #undef S
 
-#endif // !defined(PSQTAB_H_INCLUDED)
+#endif // #ifndef PSQTAB_H_INCLUDED

src/rkiss.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,7 +22,7 @@
   (at your option) any later version.
 */
 
-#if !defined(RKISS_H_INCLUDED)
+#ifndef RKISS_H_INCLUDED
 #define RKISS_H_INCLUDED
 
 #include "types.h"
@@ -43,36 +43,39 @@
 
 class RKISS {
 
-  // Keep variables always together
-  struct S { uint64_t a, b, c, d; } s;
+  uint64_t a, b, c, d;
 
-  uint64_t rotate(uint64_t x, uint64_t k) const {
+  uint64_t rotate_L(uint64_t x, unsigned k) const {
     return (x << k) | (x >> (64 - k));
   }
 
-  // Return 64 bit unsigned integer in between [0, 2^64 - 1]
   uint64_t rand64() {
 
-    const uint64_t
-      e = s.a - rotate(s.b,  7);
-    s.a = s.b ^ rotate(s.c, 13);
-    s.b = s.c + rotate(s.d, 37);
-    s.c = s.d + e;
-    return s.d = e + s.a;
-  }
-
-  // Init seed and scramble a few rounds
-  void raninit() {
-
-    s.a = 0xf1ea5eed;
-    s.b = s.c = s.d = 0xd4e12c77;
-    for (int i = 0; i < 73; i++)
-        rand64();
+    const uint64_t e = a - rotate_L(b,  7);
+    a = b ^ rotate_L(c, 13);
+    b = c + rotate_L(d, 37);
+    c = d + e;
+    return d = e + a;
   }
 
 public:
-  RKISS() { raninit(); }
+  RKISS(int seed = 73) {
+
+    a = 0xF1EA5EED, b = c = d = 0xD4E12C77;
+
+    for (int i = 0; i < seed; ++i) // Scramble a few rounds
+        rand64();
+  }
+
   template<typename T> T rand() { return T(rand64()); }
+
+  /// Special generator used to fast init magic numbers. Here the
+  /// trick is to rotate the randoms of a given quantity 's' known
+  /// to be optimal to quickly find a good magic candidate.
+  template<typename T> T magic_rand(int s) {
+    return rotate_L(rotate_L(rand<T>(), (s >> 0) & 0x3F) & rand<T>()
+                                      , (s >> 6) & 0x3F) & rand<T>();
+  }
 };
 
-#endif // !defined(RKISS_H_INCLUDED)
+#endif // #ifndef RKISS_H_INCLUDED

src/search.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,10 +17,9 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(SEARCH_H_INCLUDED)
+#ifndef SEARCH_H_INCLUDED
 #define SEARCH_H_INCLUDED
 
-#include <cstring>
 #include <memory>
 #include <stack>
 #include <vector>
@@ -38,14 +37,14 @@ namespace Search {
 /// has its own array of Stack objects, indexed by the current ply.
 
 struct Stack {
-  SplitPoint* sp;
+  SplitPoint* splitPoint;
   int ply;
   Move currentMove;
+  Move ttMove;
   Move excludedMove;
   Move killers[2];
   Depth reduction;
-  Value eval;
-  Value evalMargin;
+  Value staticEval;
   int skipNullMove;
 };
 
@@ -56,12 +55,11 @@ struct Stack {
 /// all non-pv moves.
 struct RootMove {
 
-  RootMove(){} // Needed by sort()
   RootMove(Move m) : score(-VALUE_INFINITE), prevScore(-VALUE_INFINITE) {
     pv.push_back(m); pv.push_back(MOVE_NONE);
   }
 
-  bool operator<(const RootMove& m) const { return score < m.score; }
+  bool operator<(const RootMove& m) const { return score > m.score; } // Ascending sort
   bool operator==(const Move& m) const { return pv[0] == m; }
 
   void extract_pv_from_tt(Position& pos);
@@ -75,22 +73,26 @@ struct RootMove {
 
 /// The LimitsType struct stores information sent by GUI about available time
 /// to search the current move, maximum depth/time, if we are in analysis mode
-/// or if we have to ponder while is our opponent's side to move.
+/// or if we have to ponder while it's our opponent's turn to move.
 
 struct LimitsType {
 
-  LimitsType() { memset(this, 0, sizeof(LimitsType)); }
-  bool use_time_management() const { return !(movetime | depth | nodes | infinite); }
+  LimitsType() { // Using memset on a std::vector is undefined behavior
+    time[WHITE] = time[BLACK] = inc[WHITE] = inc[BLACK] = movestogo =
+    depth = nodes = movetime = mate = infinite = ponder = 0;
+  }
+  bool use_time_management() const { return !(mate | movetime | depth | nodes | infinite); }
 
-  int time[2], inc[2], movestogo, depth, nodes, movetime, infinite, ponder;
+  std::vector<Move> searchmoves;
+  int time[COLOR_NB], inc[COLOR_NB], movestogo, depth, nodes, movetime, mate, infinite, ponder;
 };
 
 
 /// The SignalsType struct stores volatile flags updated during the search
-/// typically in an async fashion, for instance to stop the search by the GUI.
+/// typically in an async fashion e.g. to stop the search by the GUI.
 
 struct SignalsType {
-  bool stopOnPonderhit, firstRootMove, stop, failedLowAtRoot;
+  bool stop, stopOnPonderhit, firstRootMove, failedLowAtRoot;
 };
 
 typedef std::auto_ptr<std::stack<StateInfo> > StateStackPtr;
@@ -98,14 +100,15 @@ typedef std::auto_ptr<std::stack<StateInfo> > StateStackPtr;
 extern volatile SignalsType Signals;
 extern LimitsType Limits;
 extern std::vector<RootMove> RootMoves;
-extern Position RootPosition;
+extern Position RootPos;
+extern Color RootColor;
 extern Time::point SearchTime;
 extern StateStackPtr SetupStates;
 
 extern void init();
-extern size_t perft(Position& pos, Depth depth);
+extern uint64_t perft(Position& pos, Depth depth);
 extern void think();
 
 } // namespace Search
 
-#endif // !defined(SEARCH_H_INCLUDED)
+#endif // #ifndef SEARCH_H_INCLUDED

src/thread.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,8 +17,8 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <algorithm> // For std::count
 #include <cassert>
-#include <iostream>
 
 #include "movegen.h"
 #include "search.h"
@@ -29,101 +29,39 @@ using namespace Search;
 
 ThreadPool Threads; // Global object
 
-namespace { extern "C" {
-
- // start_routine() is the C function which is called when a new thread
- // is launched. It is a wrapper to member function pointed by start_fn.
-
- long start_routine(Thread* th) { (th->*(th->start_fn))(); return 0; }
-
-} }
-
-
-// Thread c'tor starts a newly-created thread of execution that will call
-// the idle loop function pointed by start_fn going immediately to sleep.
-
-Thread::Thread(Fn fn) {
-
-  is_searching = do_exit = false;
-  maxPly = splitPointsCnt = 0;
-  curSplitPoint = NULL;
-  start_fn = fn;
-  idx = Threads.size();
-
-  do_sleep = (fn != &Thread::main_loop); // Avoid a race with start_searching()
-
-  if (!thread_create(handle, start_routine, this))
-  {
-      std::cerr << "Failed to create thread number " << idx << std::endl;
-      ::exit(EXIT_FAILURE);
-  }
-}
-
-
-// Thread d'tor waits for thread termination before to return.
-
-Thread::~Thread() {
-
-  assert(do_sleep);
-
-  do_exit = true; // Search must be already finished
-  wake_up();
-  thread_join(handle); // Wait for thread termination
-}
-
-
-// Thread::timer_loop() is where the timer thread waits maxPly milliseconds and
-// then calls check_time(). If maxPly is 0 thread sleeps until is woken up.
 extern void check_time();
 
-void Thread::timer_loop() {
+namespace {
+
+ // start_routine() is the C function which is called when a new thread
+ // is launched. It is a wrapper to the virtual function idle_loop().
+
+ extern "C" { long start_routine(ThreadBase* th) { th->idle_loop(); return 0; } }
+
+
+ // Helpers to launch a thread after creation and joining before delete. Must be
+ // outside Thread c'tor and d'tor because the object will be fully initialized
+ // when start_routine (and hence virtual idle_loop) is called and when joining.
+
+ template<typename T> T* new_thread() {
+   T* th = new T();
+   thread_create(th->handle, start_routine, th); // Will go to sleep
+   return th;
+ }
+
+ void delete_thread(ThreadBase* th) {
+   th->exit = true; // Search must be already finished
+   th->notify_one();
+   thread_join(th->handle); // Wait for thread termination
+   delete th;
+ }
 
-  while (!do_exit)
-  {
-      mutex.lock();
-      sleepCondition.wait_for(mutex, maxPly ? maxPly : INT_MAX);
-      mutex.unlock();
-      check_time();
-  }
 }
 
 
-// Thread::main_loop() is where the main thread is parked waiting to be started
-// when there is a new search. Main thread will launch all the slave threads.
+// notify_one() wakes up the thread when there is some work to do
 
-void Thread::main_loop() {
-
-  while (true)
-  {
-      mutex.lock();
-
-      do_sleep = true; // Always return to sleep after a search
-      is_searching = false;
-
-      while (do_sleep && !do_exit)
-      {
-          Threads.sleepCondition.notify_one(); // Wake up UI thread if needed
-          sleepCondition.wait(mutex);
-      }
-
-      mutex.unlock();
-
-      if (do_exit)
-          return;
-
-      is_searching = true;
-
-      Search::think();
-
-      assert(is_searching);
-  }
-}
-
-
-// Thread::wake_up() wakes up the thread, normally at the beginning of the search
-// or, if "sleeping threads" is used at split time.
-
-void Thread::wake_up() {
+void ThreadBase::notify_one() {
 
   mutex.lock();
   sleepCondition.notify_one();
@@ -131,29 +69,35 @@ void Thread::wake_up() {
 }
 
 
-// Thread::wait_for_stop_or_ponderhit() is called when the maximum depth is
-// reached while the program is pondering. The point is to work around a wrinkle
-// in the UCI protocol: When pondering, the engine is not allowed to give a
-// "bestmove" before the GUI sends it a "stop" or "ponderhit" command. We simply
-// wait here until one of these commands (that raise StopRequest) is sent and
-// then return, after which the bestmove and pondermove will be printed.
+// wait_for() set the thread to sleep until condition 'b' turns true
 
-void Thread::wait_for_stop_or_ponderhit() {
-
-  Signals.stopOnPonderhit = true;
+void ThreadBase::wait_for(volatile const bool& b) {
 
   mutex.lock();
-  while (!Signals.stop) sleepCondition.wait(mutex);;
+  while (!b) sleepCondition.wait(mutex);
   mutex.unlock();
 }
 
 
-// Thread::cutoff_occurred() checks whether a beta cutoff has occurred in the
+// Thread c'tor just inits data and does not launch any execution thread.
+// Such a thread will only be started when c'tor returns.
+
+Thread::Thread() /* : splitPoints() */ { // Value-initialization bug in MSVC
+
+  searching = false;
+  maxPly = splitPointsSize = 0;
+  activeSplitPoint = NULL;
+  activePosition = NULL;
+  idx = Threads.size(); // Starts from 0
+}
+
+
+// cutoff_occurred() checks whether a beta cutoff has occurred in the
 // current active split point, or in some ancestor of the split point.
 
 bool Thread::cutoff_occurred() const {
 
-  for (SplitPoint* sp = curSplitPoint; sp; sp = sp->parent)
+  for (SplitPoint* sp = activeSplitPoint; sp; sp = sp->parentSplitPoint)
       if (sp->cutoff)
           return true;
 
@@ -161,276 +105,282 @@ bool Thread::cutoff_occurred() const {
 }
 
 
-// Thread::is_available_to() checks whether the thread is available to help the
+// Thread::available_to() checks whether the thread is available to help the
 // thread 'master' at a split point. An obvious requirement is that thread must
 // be idle. With more than two threads, this is not sufficient: If the thread is
-// the master of some active split point, it is only available as a slave to the
-// slaves which are busy searching the split point at the top of slaves split
-// point stack (the "helpful master concept" in YBWC terminology).
+// the master of some split point, it is only available as a slave to the slaves
+// which are busy searching the split point at the top of slave's split point
+// stack (the "helpful master concept" in YBWC terminology).
 
-bool Thread::is_available_to(Thread* master) const {
+bool Thread::available_to(const Thread* master) const {
 
-  if (is_searching)
+  if (searching)
       return false;
 
-  // Make a local copy to be sure doesn't become zero under our feet while
-  // testing next condition and so leading to an out of bound access.
-  int spCnt = splitPointsCnt;
+  // Make a local copy to be sure it doesn't become zero under our feet while
+  // testing next condition and so leading to an out of bounds access.
+  int size = splitPointsSize;
 
-  // No active split points means that the thread is available as a slave for any
+  // No split points means that the thread is available as a slave for any
   // other thread otherwise apply the "helpful master" concept if possible.
-  return !spCnt || (splitPoints[spCnt - 1].slavesMask & (1ULL << master->idx));
+  return !size || splitPoints[size - 1].slavesMask.test(master->idx);
 }
 
 
-// init() is called at startup. Initializes lock and condition variable and
-// launches requested threads sending them immediately to sleep. We cannot use
-// a c'tor becuase Threads is a static object and we need a fully initialized
-// engine at this point due to allocation of endgames in Thread c'tor.
+// TimerThread::idle_loop() is where the timer thread waits msec milliseconds
+// and then calls check_time(). If msec is 0 thread sleeps until it's woken up.
+
+void TimerThread::idle_loop() {
+
+  while (!exit)
+  {
+      mutex.lock();
+
+      if (!exit)
+          sleepCondition.wait_for(mutex, run ? Resolution : INT_MAX);
+
+      mutex.unlock();
+
+      if (run)
+          check_time();
+  }
+}
+
+
+// MainThread::idle_loop() is where the main thread is parked waiting to be started
+// when there is a new search. The main thread will launch all the slave threads.
+
+void MainThread::idle_loop() {
+
+  while (true)
+  {
+      mutex.lock();
+
+      thinking = false;
+
+      while (!thinking && !exit)
+      {
+          Threads.sleepCondition.notify_one(); // Wake up the UI thread if needed
+          sleepCondition.wait(mutex);
+      }
+
+      mutex.unlock();
+
+      if (exit)
+          return;
+
+      searching = true;
+
+      Search::think();
+
+      assert(searching);
+
+      searching = false;
+  }
+}
+
+
+// init() is called at startup to create and launch requested threads, that will
+// go immediately to sleep. We cannot use a c'tor because Threads is a static
+// object and we need a fully initialized engine at this point due to allocation
+// of Endgames in Thread c'tor.
 
 void ThreadPool::init() {
 
-  timer = new Thread(&Thread::timer_loop);
-  threads.push_back(new Thread(&Thread::main_loop));
+  timer = new_thread<TimerThread>();
+  push_back(new_thread<MainThread>());
   read_uci_options();
 }
 
 
-// exit() cleanly terminates the threads before the program exits.
+// exit() cleanly terminates the threads before the program exits. Cannot be done in
+// d'tor because we have to terminate the threads before to free ThreadPool object.
 
 void ThreadPool::exit() {
 
-  for (size_t i = 0; i < threads.size(); i++)
-      delete threads[i];
+  delete_thread(timer); // As first because check_time() accesses threads data
 
-  delete timer;
+  for (iterator it = begin(); it != end(); ++it)
+      delete_thread(*it);
 }
 
 
 // read_uci_options() updates internal threads parameters from the corresponding
 // UCI options and creates/destroys threads to match the requested number. Thread
-// objects are dynamically allocated to avoid creating in advance all possible
-// threads, with included pawns and material tables, if only few are used.
+// objects are dynamically allocated to avoid creating all possible threads
+// in advance (which include pawns and material tables), even if only a few
+// are to be used.
 
 void ThreadPool::read_uci_options() {
 
-  maxThreadsPerSplitPoint = Options["Max Threads per Split Point"];
-  minimumSplitDepth       = Options["Min Split Depth"] * ONE_PLY;
-  useSleepingThreads      = Options["Use Sleeping Threads"];
-  size_t requested        = Options["Threads"];
+  minimumSplitDepth = Options["Min Split Depth"] * ONE_PLY;
+  size_t requested  = Options["Threads"];
 
   assert(requested > 0);
 
-  while (threads.size() < requested)
-      threads.push_back(new Thread(&Thread::idle_loop));
+  // If zero (default) then set best minimum split depth automatically
+  if (!minimumSplitDepth)
+      minimumSplitDepth = requested < 8 ? 4 * ONE_PLY : 7 * ONE_PLY;
 
-  while (threads.size() > requested)
+  while (size() < requested)
+      push_back(new_thread<Thread>());
+
+  while (size() > requested)
   {
-      delete threads.back();
-      threads.pop_back();
+      delete_thread(back());
+      pop_back();
   }
 }
 
 
-// wake_up() is called before a new search to start the threads that are waiting
-// on the sleep condition and to reset maxPly. When useSleepingThreads is set
-// threads will be woken up at split time.
+// available_slave() tries to find an idle thread which is available as a slave
+// for the thread 'master'.
 
-void ThreadPool::wake_up() const {
+Thread* ThreadPool::available_slave(const Thread* master) const {
 
-  for (size_t i = 0; i < threads.size(); i++)
-  {
-      threads[i]->maxPly = 0;
-      threads[i]->do_sleep = false;
+  for (const_iterator it = begin(); it != end(); ++it)
+      if ((*it)->available_to(master))
+          return *it;
 
-      if (!useSleepingThreads)
-          threads[i]->wake_up();
-  }
-}
-
-
-// sleep() is called after the search finishes to ask all the threads but the
-// main one to go waiting on a sleep condition.
-
-void ThreadPool::sleep() const {
-
-  // Main thread will go to sleep by itself to avoid a race with start_searching()
-  for (size_t i = 1; i < threads.size(); i++)
-      threads[i]->do_sleep = true;
-}
-
-
-// available_slave_exists() tries to find an idle thread which is available as
-// a slave for the thread 'master'.
-
-bool ThreadPool::available_slave_exists(Thread* master) const {
-
-  for (size_t i = 0; i < threads.size(); i++)
-      if (threads[i]->is_available_to(master))
-          return true;
-
-  return false;
+  return NULL;
 }
 
 
 // split() does the actual work of distributing the work at a node between
 // several available threads. If it does not succeed in splitting the node
-// (because no idle threads are available, or because we have no unused split
-// point objects), the function immediately returns. If splitting is possible, a
-// SplitPoint object is initialized with all the data that must be copied to the
-// helper threads and then helper threads are told that they have been assigned
-// work. This will cause them to instantly leave their idle loops and call
-// search(). When all threads have returned from search() then split() returns.
+// (because no idle threads are available), the function immediately returns.
+// If splitting is possible, a SplitPoint object is initialized with all the
+// data that must be copied to the helper threads and then helper threads are
+// told that they have been assigned work. This will cause them to instantly
+// leave their idle loops and call search(). When all threads have returned from
+// search() then split() returns.
 
 template <bool Fake>
-Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
-                        Value bestValue, Move* bestMove, Depth depth,
-                        Move threatMove, int moveCount, MovePicker* mp, int nodeType) {
+void Thread::split(Position& pos, const Stack* ss, Value alpha, Value beta, Value* bestValue,
+                   Move* bestMove, Depth depth, int moveCount,
+                   MovePicker* movePicker, int nodeType, bool cutNode) {
 
   assert(pos.pos_is_ok());
-  assert(bestValue > -VALUE_INFINITE);
-  assert(bestValue <= alpha);
-  assert(alpha < beta);
-  assert(beta <= VALUE_INFINITE);
-  assert(depth > DEPTH_ZERO);
-
-  Thread* master = pos.this_thread();
-
-  if (master->splitPointsCnt >= MAX_SPLITPOINTS_PER_THREAD)
-      return bestValue;
+  assert(-VALUE_INFINITE < *bestValue && *bestValue <= alpha && alpha < beta && beta <= VALUE_INFINITE);
+  assert(depth >= Threads.minimumSplitDepth);
+  assert(searching);
+  assert(splitPointsSize < MAX_SPLITPOINTS_PER_THREAD);
 
   // Pick the next available split point from the split point stack
-  SplitPoint& sp = master->splitPoints[master->splitPointsCnt];
+  SplitPoint& sp = splitPoints[splitPointsSize];
 
-  sp.parent = master->curSplitPoint;
-  sp.master = master;
-  sp.cutoff = false;
-  sp.slavesMask = 1ULL << master->idx;
+  sp.masterThread = this;
+  sp.parentSplitPoint = activeSplitPoint;
+  sp.slavesMask = 0, sp.slavesMask.set(idx);
   sp.depth = depth;
+  sp.bestValue = *bestValue;
   sp.bestMove = *bestMove;
-  sp.threatMove = threatMove;
   sp.alpha = alpha;
   sp.beta = beta;
   sp.nodeType = nodeType;
-  sp.bestValue = bestValue;
-  sp.mp = mp;
+  sp.cutNode = cutNode;
+  sp.movePicker = movePicker;
   sp.moveCount = moveCount;
   sp.pos = &pos;
   sp.nodes = 0;
+  sp.cutoff = false;
   sp.ss = ss;
 
-  assert(master->is_searching);
-
-  master->curSplitPoint = &sp;
-  int slavesCnt = 0;
-
   // Try to allocate available threads and ask them to start searching setting
-  // is_searching flag. This must be done under lock protection to avoid concurrent
+  // 'searching' flag. This must be done under lock protection to avoid concurrent
   // allocation of the same slave by another master.
+  Threads.mutex.lock();
   sp.mutex.lock();
-  mutex.lock();
 
-  for (size_t i = 0; i < threads.size() && !Fake; ++i)
-      if (threads[i]->is_available_to(master))
+  sp.allSlavesSearching = true; // Must be set under lock protection
+  ++splitPointsSize;
+  activeSplitPoint = &sp;
+  activePosition = NULL;
+
+  if (!Fake)
+      for (Thread* slave; (slave = Threads.available_slave(this)) != NULL; )
       {
-          sp.slavesMask |= 1ULL << i;
-          threads[i]->curSplitPoint = &sp;
-          threads[i]->is_searching = true; // Slave leaves idle_loop()
-
-          if (useSleepingThreads)
-              threads[i]->wake_up();
-
-          if (++slavesCnt + 1 >= maxThreadsPerSplitPoint) // Master is always included
-              break;
+          sp.slavesMask.set(slave->idx);
+          slave->activeSplitPoint = &sp;
+          slave->searching = true; // Slave leaves idle_loop()
+          slave->notify_one(); // Could be sleeping
       }
 
-  master->splitPointsCnt++;
-
-  mutex.unlock();
-  sp.mutex.unlock();
-
   // Everything is set up. The master thread enters the idle loop, from which
-  // it will instantly launch a search, because its is_searching flag is set.
+  // it will instantly launch a search, because its 'searching' flag is set.
   // The thread will return from the idle loop when all slaves have finished
   // their work at this split point.
-  if (slavesCnt || Fake)
-  {
-      master->idle_loop();
+  sp.mutex.unlock();
+  Threads.mutex.unlock();
 
-      // In helpful master concept a master can help only a sub-tree of its split
-      // point, and because here is all finished is not possible master is booked.
-      assert(!master->is_searching);
-  }
+  Thread::idle_loop(); // Force a call to base class idle_loop()
+
+  // In the helpful master concept, a master can help only a sub-tree of its
+  // split point and because everything is finished here, it's not possible
+  // for the master to be booked.
+  assert(!searching);
+  assert(!activePosition);
 
   // We have returned from the idle loop, which means that all threads are
-  // finished. Note that setting is_searching and decreasing splitPointsCnt is
-  // done under lock protection to avoid a race with Thread::is_available_to().
-  sp.mutex.lock(); // To protect sp.nodes
-  mutex.lock();
+  // finished. Note that setting 'searching' and decreasing splitPointsSize is
+  // done under lock protection to avoid a race with Thread::available_to().
+  Threads.mutex.lock();
+  sp.mutex.lock();
 
-  master->is_searching = true;
-  master->splitPointsCnt--;
-  master->curSplitPoint = sp.parent;
+  searching = true;
+  --splitPointsSize;
+  activeSplitPoint = sp.parentSplitPoint;
+  activePosition = &pos;
   pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
   *bestMove = sp.bestMove;
+  *bestValue = sp.bestValue;
 
-  mutex.unlock();
   sp.mutex.unlock();
-
-  return sp.bestValue;
+  Threads.mutex.unlock();
 }
 
 // Explicit template instantiations
-template Value ThreadPool::split<false>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
-template Value ThreadPool::split<true>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
+template void Thread::split<false>(Position&, const Stack*, Value, Value, Value*, Move*, Depth, int, MovePicker*, int, bool);
+template void Thread::split< true>(Position&, const Stack*, Value, Value, Value*, Move*, Depth, int, MovePicker*, int, bool);
 
 
-// set_timer() is used to set the timer to trigger after msec milliseconds.
-// If msec is 0 then timer is stopped.
+// wait_for_think_finished() waits for main thread to go to sleep then returns
 
-void ThreadPool::set_timer(int msec) {
+void ThreadPool::wait_for_think_finished() {
 
-  timer->mutex.lock();
-  timer->maxPly = msec;
-  timer->sleepCondition.notify_one(); // Wake up and restart the timer
-  timer->mutex.unlock();
-}
-
-
-// wait_for_search_finished() waits for main thread to go to sleep, this means
-// search is finished. Then returns.
-
-void ThreadPool::wait_for_search_finished() {
-
-  Thread* t = main_thread();
+  MainThread* t = main();
   t->mutex.lock();
-  t->sleepCondition.notify_one(); // In case is waiting for stop or ponderhit
-  while (!t->do_sleep) sleepCondition.wait(t->mutex);
+  while (t->thinking) sleepCondition.wait(t->mutex);
   t->mutex.unlock();
 }
 
 
-// start_searching() wakes up the main thread sleeping in  main_loop() so to start
-// a new search, then returns immediately.
+// start_thinking() wakes up the main thread sleeping in MainThread::idle_loop()
+// so to start a new search, then returns immediately.
 
-void ThreadPool::start_searching(const Position& pos, const LimitsType& limits,
-                                 const std::vector<Move>& searchMoves, StateStackPtr& states) {
-  wait_for_search_finished();
+void ThreadPool::start_thinking(const Position& pos, const LimitsType& limits, StateStackPtr& states) {
+
+  wait_for_think_finished();
 
   SearchTime = Time::now(); // As early as possible
 
   Signals.stopOnPonderhit = Signals.firstRootMove = false;
   Signals.stop = Signals.failedLowAtRoot = false;
 
-  RootPosition = pos;
-  Limits = limits;
-  SetupStates = states; // Ownership transfer here
   RootMoves.clear();
+  RootPos = pos;
+  Limits = limits;
+  if (states.get()) // If we don't set a new position, preserve current state
+  {
+      SetupStates = states; // Ownership transfer here
+      assert(!states.get());
+  }
 
-  for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
-      if (searchMoves.empty() || count(searchMoves.begin(), searchMoves.end(), ml.move()))
-          RootMoves.push_back(RootMove(ml.move()));
+  for (MoveList<LEGAL> it(pos); *it; ++it)
+      if (   limits.searchmoves.empty()
+          || std::count(limits.searchmoves.begin(), limits.searchmoves.end(), *it))
+          RootMoves.push_back(RootMove(*it));
 
-  main_thread()->do_sleep = false;
-  main_thread()->wake_up();
+  main()->thinking = true;
+  main()->notify_one(); // Starts main thread
 }

src/thread.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,9 +17,10 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(THREAD_H_INCLUDED)
+#ifndef THREAD_H_INCLUDED
 #define THREAD_H_INCLUDED
 
+#include <bitset>
 #include <vector>
 
 #include "material.h"
@@ -28,7 +29,7 @@
 #include "position.h"
 #include "search.h"
 
-const int MAX_THREADS = 32;
+const int MAX_THREADS = 128;
 const int MAX_SPLITPOINTS_PER_THREAD = 8;
 
 struct Mutex {
@@ -56,27 +57,28 @@ private:
   WaitCondition c;
 };
 
-class Thread;
+struct Thread;
 
 struct SplitPoint {
 
   // Const data after split point has been setup
   const Position* pos;
   const Search::Stack* ss;
+  Thread* masterThread;
   Depth depth;
   Value beta;
   int nodeType;
-  Thread* master;
-  Move threatMove;
+  bool cutNode;
 
   // Const pointers to shared data
-  MovePicker* mp;
-  SplitPoint* parent;
+  MovePicker* movePicker;
+  SplitPoint* parentSplitPoint;
 
   // Shared data
   Mutex mutex;
-  volatile uint64_t slavesMask;
-  volatile int64_t nodes;
+  std::bitset<MAX_THREADS> slavesMask;
+  volatile bool allSlavesSearching;
+  volatile uint64_t nodes;
   volatile Value alpha;
   volatile Value bestValue;
   volatile Move bestMove;
@@ -85,84 +87,91 @@ struct SplitPoint {
 };
 
 
+/// ThreadBase struct is the base of the hierarchy from where we derive all the
+/// specialized thread classes.
+
+struct ThreadBase {
+
+  ThreadBase() : handle(NativeHandle()), exit(false) {}
+  virtual ~ThreadBase() {}
+  virtual void idle_loop() = 0;
+  void notify_one();
+  void wait_for(volatile const bool& b);
+
+  Mutex mutex;
+  ConditionVariable sleepCondition;
+  NativeHandle handle;
+  volatile bool exit;
+};
+
+
 /// Thread struct keeps together all the thread related stuff like locks, state
 /// and especially split points. We also 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 Thread {
+struct Thread : public ThreadBase {
 
-  typedef void (Thread::* Fn) (); // Pointer to member function
-
-public:
-  Thread(Fn fn);
- ~Thread();
-
-  void wake_up();
+  Thread();
+  virtual void idle_loop();
   bool cutoff_occurred() const;
-  bool is_available_to(Thread* master) const;
-  void idle_loop();
-  void main_loop();
-  void timer_loop();
-  void wait_for_stop_or_ponderhit();
+  bool available_to(const Thread* master) const;
+
+  template <bool Fake>
+  void split(Position& pos, const Search::Stack* ss, Value alpha, Value beta, Value* bestValue, Move* bestMove,
+             Depth depth, int moveCount, MovePicker* movePicker, int nodeType, bool cutNode);
 
   SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD];
-  MaterialTable materialTable;
-  PawnTable pawnTable;
+  Material::Table materialTable;
+  Endgames endgames;
+  Pawns::Table pawnsTable;
+  Position* activePosition;
   size_t idx;
   int maxPly;
-  Mutex mutex;
-  ConditionVariable sleepCondition;
-  NativeHandle handle;
-  Fn start_fn;
-  SplitPoint* volatile curSplitPoint;
-  volatile int splitPointsCnt;
-  volatile bool is_searching;
-  volatile bool do_sleep;
-  volatile bool do_exit;
+  SplitPoint* volatile activeSplitPoint;
+  volatile int splitPointsSize;
+  volatile bool searching;
 };
 
 
-/// ThreadPool class handles all the threads related stuff like init, starting,
-/// parking and, the most important, launching a slave thread at a split point.
+/// MainThread and TimerThread are derived classes used to characterize the two
+/// special threads: the main one and the recurring timer.
+
+struct MainThread : public Thread {
+  MainThread() : thinking(true) {} // Avoid a race with start_thinking()
+  virtual void idle_loop();
+  volatile bool thinking;
+};
+
+struct TimerThread : public ThreadBase {
+  TimerThread() : run(false) {}
+  virtual void idle_loop();
+  bool run;
+  static const int Resolution = 5; // msec between two check_time() calls
+};
+
+
+/// ThreadPool struct handles all the threads related stuff like init, starting,
+/// parking and, most importantly, launching a slave thread at a split point.
 /// All the access to shared thread data is done through this class.
 
-class ThreadPool {
+struct ThreadPool : public std::vector<Thread*> {
 
-public:
   void init(); // No c'tor and d'tor, threads rely on globals that should
-  void exit(); // be initialized and valid during the whole thread lifetime.
+  void exit(); // be initialized and are valid during the whole thread lifetime.
 
-  Thread& operator[](size_t id) { return *threads[id]; }
-  bool use_sleeping_threads() const { return useSleepingThreads; }
-  int min_split_depth() const { return minimumSplitDepth; }
-  size_t size() const { return threads.size(); }
-  Thread* main_thread() { return threads[0]; }
-
-  void wake_up() const;
-  void sleep() const;
+  MainThread* main() { return static_cast<MainThread*>((*this)[0]); }
   void read_uci_options();
-  bool available_slave_exists(Thread* master) const;
-  void set_timer(int msec);
-  void wait_for_search_finished();
-  void start_searching(const Position&, const Search::LimitsType&,
-                       const std::vector<Move>&, Search::StateStackPtr&);
+  Thread* available_slave(const Thread* master) const;
+  void wait_for_think_finished();
+  void start_thinking(const Position&, const Search::LimitsType&, Search::StateStackPtr&);
 
-  template <bool Fake>
-  Value split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value bestValue, Move* bestMove,
-              Depth depth, Move threatMove, int moveCount, MovePicker* mp, int nodeType);
-private:
-  friend class Thread;
-
-  std::vector<Thread*> threads;
-  Thread* timer;
+  Depth minimumSplitDepth;
   Mutex mutex;
   ConditionVariable sleepCondition;
-  Depth minimumSplitDepth;
-  int maxThreadsPerSplitPoint;
-  bool useSleepingThreads;
+  TimerThread* timer;
 };
 
 extern ThreadPool Threads;
 
-#endif // !defined(THREAD_H_INCLUDED)
+#endif // #ifndef THREAD_H_INCLUDED

src/timeman.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,8 +17,9 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <cmath>
 #include <algorithm>
+#include <cfloat>
+#include <cmath>
 
 #include "search.h"
 #include "timeman.h"
@@ -26,66 +27,51 @@
 
 namespace {
 
-  /// Constants
-
-  const int MoveHorizon  = 50;    // Plan time management at most this many moves ahead
-  const float MaxRatio   = 3.0f;  // When in trouble, we can step over reserved time with this ratio
-  const float StealRatio = 0.33f; // However we must not steal time from remaining moves over this ratio
-
-
-  // MoveImportance[] is based on naive statistical analysis of "how many games are still undecided
-  // after n half-moves". Game is considered "undecided" as long as neither side has >275cp advantage.
-  // Data was extracted from CCRL game database with some simple filtering criteria.
-  const int MoveImportance[512] = {
-    7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780,
-    7780, 7780, 7780, 7780, 7778, 7778, 7776, 7776, 7776, 7773, 7770, 7768, 7766, 7763, 7757, 7751,
-    7743, 7735, 7724, 7713, 7696, 7689, 7670, 7656, 7627, 7605, 7571, 7549, 7522, 7493, 7462, 7425,
-    7385, 7350, 7308, 7272, 7230, 7180, 7139, 7094, 7055, 7010, 6959, 6902, 6841, 6778, 6705, 6651,
-    6569, 6508, 6435, 6378, 6323, 6253, 6152, 6085, 5995, 5931, 5859, 5794, 5717, 5646, 5544, 5462,
-    5364, 5282, 5172, 5078, 4988, 4901, 4831, 4764, 4688, 4609, 4536, 4443, 4365, 4293, 4225, 4155,
-    4085, 4005, 3927, 3844, 3765, 3693, 3634, 3560, 3479, 3404, 3331, 3268, 3207, 3146, 3077, 3011,
-    2947, 2894, 2828, 2776, 2727, 2676, 2626, 2589, 2538, 2490, 2442, 2394, 2345, 2302, 2243, 2192,
-    2156, 2115, 2078, 2043, 2004, 1967, 1922, 1893, 1845, 1809, 1772, 1736, 1702, 1674, 1640, 1605,
-    1566, 1536, 1509, 1479, 1452, 1423, 1388, 1362, 1332, 1304, 1289, 1266, 1250, 1228, 1206, 1180,
-    1160, 1134, 1118, 1100, 1080, 1068, 1051, 1034, 1012, 1001, 980, 960, 945, 934, 916, 900, 888,
-    878, 865, 852, 828, 807, 787, 770, 753, 744, 731, 722, 706, 700, 683, 676, 671, 664, 652, 641,
-    634, 627, 613, 604, 591, 582, 568, 560, 552, 540, 534, 529, 519, 509, 495, 484, 474, 467, 460,
-    450, 438, 427, 419, 410, 406, 399, 394, 387, 382, 377, 372, 366, 359, 353, 348, 343, 337, 333,
-    328, 321, 315, 309, 303, 298, 293, 287, 284, 281, 277, 273, 265, 261, 255, 251, 247, 241, 240,
-    235, 229, 218, 217, 213, 212, 208, 206, 197, 193, 191, 189, 185, 184, 180, 177, 172, 170, 170,
-    170, 166, 163, 159, 158, 156, 155, 151, 146, 141, 138, 136, 132, 130, 128, 125, 123, 122, 118,
-    118, 118, 117, 115, 114, 108, 107, 105, 105, 105, 102, 97, 97, 95, 94, 93, 91, 88, 86, 83, 80,
-    80, 79, 79, 79, 78, 76, 75, 72, 72, 71, 70, 68, 65, 63, 61, 61, 59, 59, 59, 58, 56, 55, 54, 54,
-    52, 49, 48, 48, 48, 48, 45, 45, 45, 44, 43, 41, 41, 41, 41, 40, 40, 38, 37, 36, 34, 34, 34, 33,
-    31, 29, 29, 29, 28, 28, 28, 28, 28, 28, 28, 27, 27, 27, 27, 27, 24, 24, 23, 23, 22, 21, 20, 20,
-    19, 19, 19, 19, 19, 18, 18, 18, 18, 17, 17, 17, 17, 17, 16, 16, 15, 15, 14, 14, 14, 12, 12, 11,
-    9, 9, 9, 9, 9, 9, 9, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
-    8, 8, 8, 8, 7, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 2, 2, 2, 2,
-    2, 1, 1, 1, 1, 1, 1, 1 };
-
-  int move_importance(int ply) { return MoveImportance[std::min(ply, 511)]; }
-
-
-  /// Function Prototypes
-
   enum TimeType { OptimumTime, MaxTime };
 
-  template<TimeType>
-  int remaining(int myTime, int movesToGo, int fullMoveNumber, int slowMover);
-}
+  const int MoveHorizon   = 50;   // Plan time management at most this many moves ahead
+  const double MaxRatio   = 7.0;  // When in trouble, we can step over reserved time with this ratio
+  const double StealRatio = 0.33; // However we must not steal time from remaining moves over this ratio
+
+  const double xscale     = 9.3;
+  const double xshift     = 59.8;
+  const double skewfactor = 0.172;
 
 
-void TimeManager::pv_instability(int curChanges, int prevChanges) {
+  // move_importance() is a skew-logistic function based on naive statistical
+  // analysis of "how many games are still undecided after n half-moves". Game
+  // is considered "undecided" as long as neither side has >275cp advantage.
+  // Data was extracted from CCRL game database with some simple filtering criteria.
 
-  unstablePVExtraTime =  curChanges  * (optimumSearchTime / 2)
-                       + prevChanges * (optimumSearchTime / 3);
-}
+  double move_importance(int ply) {
+
+    return pow((1 + exp((ply - xshift) / xscale)), -skewfactor) + DBL_MIN; // Ensure non-zero
+  }
+
+  template<TimeType T>
+  int remaining(int myTime, int movesToGo, int currentPly, int slowMover)
+  {
+    const double TMaxRatio   = (T == OptimumTime ? 1 : MaxRatio);
+    const double TStealRatio = (T == OptimumTime ? 0 : StealRatio);
+
+    double thisMoveImportance = (move_importance(currentPly) * slowMover) / 100;
+    double otherMovesImportance = 0;
+
+    for (int i = 1; i < movesToGo; ++i)
+        otherMovesImportance += move_importance(currentPly + 2 * i);
+
+    double ratio1 = (TMaxRatio * thisMoveImportance) / (TMaxRatio * thisMoveImportance + otherMovesImportance);
+    double ratio2 = (thisMoveImportance + TStealRatio * otherMovesImportance) / (thisMoveImportance + otherMovesImportance);
+
+    return int(myTime * std::min(ratio1, ratio2));
+  }
+
+} // namespace
 
 
 void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color us)
 {
-  /* We support four different kind of time controls:
+  /* We support four different kinds of time controls:
 
       increment == 0 && movesToGo == 0 means: x basetime  [sudden death!]
       increment == 0 && movesToGo != 0 means: x moves in y minutes
@@ -109,15 +95,15 @@ void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color u
   int minThinkingTime      = Options["Minimum Thinking Time"];
   int slowMover            = Options["Slow Mover"];
 
-  // Initialize to maximum values but unstablePVExtraTime that is reset
-  unstablePVExtraTime = 0;
-  optimumSearchTime = maximumSearchTime = limits.time[us];
+  // Initialize unstablePvFactor to 1 and search times to maximum values
+  unstablePvFactor = 1;
+  optimumSearchTime = maximumSearchTime = std::max(limits.time[us], minThinkingTime);
 
-  // We calculate optimum time usage for different hypothetic "moves to go"-values and choose the
+  // We calculate optimum time usage for different hypothetical "moves to go"-values and choose the
   // minimum of calculated search time values. Usually the greatest hypMTG gives the minimum values.
-  for (hypMTG = 1; hypMTG <= (limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon); hypMTG++)
+  for (hypMTG = 1; hypMTG <= (limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon); ++hypMTG)
   {
-      // Calculate thinking time for hypothetic "moves to go"-value
+      // Calculate thinking time for hypothetical "moves to go"-value
       hypMyTime =  limits.time[us]
                  + limits.inc[us] * (hypMTG - 1)
                  - emergencyBaseTime
@@ -138,25 +124,3 @@ void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color u
   // Make sure that maxSearchTime is not over absoluteMaxSearchTime
   optimumSearchTime = std::min(optimumSearchTime, maximumSearchTime);
 }
-
-
-namespace {
-
-  template<TimeType T>
-  int remaining(int myTime, int movesToGo, int currentPly, int slowMover)
-  {
-    const float TMaxRatio   = (T == OptimumTime ? 1 : MaxRatio);
-    const float TStealRatio = (T == OptimumTime ? 0 : StealRatio);
-
-    int thisMoveImportance = move_importance(currentPly) * slowMover / 100;
-    int otherMovesImportance = 0;
-
-    for (int i = 1; i < movesToGo; i++)
-        otherMovesImportance += move_importance(currentPly + 2 * i);
-
-    float ratio1 = (TMaxRatio * thisMoveImportance) / float(TMaxRatio * thisMoveImportance + otherMovesImportance);
-    float ratio2 = (thisMoveImportance + TStealRatio * otherMovesImportance) / float(thisMoveImportance + otherMovesImportance);
-
-    return int(floor(myTime * std::min(ratio1, ratio2)));
-  }
-}

src/timeman.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,23 +17,23 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(TIMEMAN_H_INCLUDED)
+#ifndef TIMEMAN_H_INCLUDED
 #define TIMEMAN_H_INCLUDED
 
 /// The TimeManager class computes the optimal time to think depending on the
-/// maximum available time, the move game number and other parameters.
+/// maximum available time, the game move number and other parameters.
 
 class TimeManager {
 public:
   void init(const Search::LimitsType& limits, int currentPly, Color us);
-  void pv_instability(int curChanges, int prevChanges);
-  int available_time() const { return optimumSearchTime + unstablePVExtraTime; }
+  void pv_instability(double bestMoveChanges) { unstablePvFactor = 1 + bestMoveChanges; }
+  int available_time() const { return int(optimumSearchTime * unstablePvFactor * 0.71); }
   int maximum_time() const { return maximumSearchTime; }
 
 private:
   int optimumSearchTime;
   int maximumSearchTime;
-  int unstablePVExtraTime;
+  double unstablePvFactor;
 };
 
-#endif // !defined(TIMEMAN_H_INCLUDED)
+#endif // #ifndef TIMEMAN_H_INCLUDED

src/tt.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -25,42 +25,32 @@
 
 TranspositionTable TT; // Our global transposition table
 
-TranspositionTable::TranspositionTable() {
 
-  size = generation = 0;
-  entries = NULL;
-}
+/// 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.
 
-TranspositionTable::~TranspositionTable() {
+void TranspositionTable::resize(uint64_t mbSize) {
 
-  delete [] entries;
-}
+  assert(msb((mbSize << 20) / sizeof(TTEntry)) < 32);
 
+  uint32_t size = ClusterSize << msb((mbSize << 20) / sizeof(TTEntry[ClusterSize]));
 
-/// TranspositionTable::set_size() sets the size of the transposition table,
-/// measured in megabytes. Transposition table consists of a power of 2 number of
-/// TTCluster and each cluster consists of ClusterSize number of TTEntries. Each
-/// non-empty entry contains information of exactly one position.
-
-void TranspositionTable::set_size(size_t mbSize) {
-
-  size_t newSize = 1ULL << msb((mbSize << 20) / sizeof(TTCluster));
-
-  if (newSize == size)
+  if (hashMask == size - ClusterSize)
       return;
 
-  size = newSize;
-  delete [] entries;
-  entries = new (std::nothrow) TTCluster[size];
+  hashMask = size - ClusterSize;
+  free(mem);
+  mem = calloc(size * sizeof(TTEntry) + CACHE_LINE_SIZE - 1, 1);
 
-  if (!entries)
+  if (!mem)
   {
       std::cerr << "Failed to allocate " << mbSize
                 << "MB for transposition table." << std::endl;
       exit(EXIT_FAILURE);
   }
 
-  clear(); // Operator new is not guaranteed to initialize memory to zero
+  table = (TTEntry*)((uintptr_t(mem) + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1));
 }
 
 
@@ -70,47 +60,7 @@ void TranspositionTable::set_size(size_t mbSize) {
 
 void TranspositionTable::clear() {
 
-  memset(entries, 0, size * sizeof(TTCluster));
-}
-
-
-/// TranspositionTable::store() writes a new entry containing position key and
-/// valuable information of current position. The lowest order bits of position
-/// key are used to decide on which cluster the position will be placed.
-/// When a new entry is written and there are no empty entries available in cluster,
-/// it replaces the least valuable of entries. A TTEntry t1 is considered to be
-/// more valuable than a TTEntry t2 if t1 is from the current search and t2 is from
-/// a previous search, or if the depth of t1 is bigger than the depth of t2.
-
-void TranspositionTable::store(const Key posKey, Value v, Bound t, Depth d, Move m, Value statV, Value kingD) {
-
-  int c1, c2, c3;
-  TTEntry *tte, *replace;
-  uint32_t posKey32 = posKey >> 32; // Use the high 32 bits as key inside the cluster
-
-  tte = replace = first_entry(posKey);
-
-  for (int i = 0; i < ClusterSize; i++, tte++)
-  {
-      if (!tte->key() || tte->key() == posKey32) // Empty or overwrite old
-      {
-          // Preserve any existing ttMove
-          if (m == MOVE_NONE)
-              m = tte->move();
-
-          tte->save(posKey32, v, t, d, m, generation, statV, kingD);
-          return;
-      }
-
-      // Implement replace strategy
-      c1 = (replace->generation() == generation ?  2 : 0);
-      c2 = (tte->generation() == generation || tte->type() == BOUND_EXACT ? -2 : 0);
-      c3 = (tte->depth() < replace->depth() ?  1 : 0);
-
-      if (c1 + c2 + c3 > 0)
-          replace = tte;
-  }
-  replace->save(posKey32, v, t, d, m, generation, statV, kingD);
+  std::memset(table, 0, (hashMask + ClusterSize) * sizeof(TTEntry));
 }
 
 
@@ -118,24 +68,54 @@ void TranspositionTable::store(const Key posKey, Value v, Bound t, Depth d, Move
 /// transposition table. Returns a pointer to the TTEntry or NULL if
 /// position is not found.
 
-TTEntry* TranspositionTable::probe(const Key posKey) const {
+const TTEntry* TranspositionTable::probe(const Key key) const {
 
-  uint32_t posKey32 = posKey >> 32;
-  TTEntry* tte = first_entry(posKey);
+  TTEntry* tte = first_entry(key);
+  uint32_t key32 = key >> 32;
 
-  for (int i = 0; i < ClusterSize; i++, tte++)
-      if (tte->key() == posKey32)
+  for (unsigned i = 0; i < ClusterSize; ++i, ++tte)
+      if (tte->key32 == key32)
+      {
+          tte->generation8 = generation; // Refresh
           return tte;
+      }
 
   return NULL;
 }
 
 
-/// TranspositionTable::new_search() is called at the beginning of every new
-/// search. It increments the "generation" variable, which is used to
-/// distinguish transposition table entries from previous searches from
-/// entries from the current search.
+/// TranspositionTable::store() writes a new entry containing position key and
+/// valuable information of current position. The lowest order bits of position
+/// key are used to decide in which cluster the position will be placed.
+/// When a new entry is written and there are no empty entries available in the
+/// cluster, it replaces the least valuable of the entries. A TTEntry t1 is considered
+/// to be more valuable than a TTEntry t2 if t1 is from the current search and t2
+/// is from a previous search, or if the depth of t1 is bigger than the depth of t2.
 
-void TranspositionTable::new_search() {
-  generation++;
+void TranspositionTable::store(const Key key, Value v, Bound b, Depth d, Move m, Value statV) {
+
+  TTEntry *tte, *replace;
+  uint32_t key32 = key >> 32; // Use the high 32 bits as key inside the cluster
+
+  tte = replace = first_entry(key);
+
+  for (unsigned i = 0; i < ClusterSize; ++i, ++tte)
+  {
+      if (!tte->key32 || tte->key32 == key32) // Empty or overwrite old
+      {
+          if (!m)
+              m = tte->move(); // Preserve any existing ttMove
+
+          replace = tte;
+          break;
+      }
+
+      // Implement replace strategy
+      if (  (    tte->generation8 == generation || tte->bound() == BOUND_EXACT)
+          - (replace->generation8 == generation)
+          - (tte->depth16 < replace->depth16) < 0)
+          replace = tte;
+  }
+
+  replace->save(key32, v, b, d, m, generation, statV);
 }

src/tt.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,99 +17,76 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(TT_H_INCLUDED)
+#ifndef TT_H_INCLUDED
 #define TT_H_INCLUDED
 
 #include "misc.h"
 #include "types.h"
 
-/// The TTEntry is the class of transposition table entries
+/// The TTEntry is the 14 bytes transposition table entry, defined as below:
 ///
-/// A TTEntry needs 128 bits to be stored
-///
-/// bit  0-31: key
-/// bit 32-63: data
-/// bit 64-79: value
-/// bit 80-95: depth
-/// bit 96-111: static value
-/// bit 112-127: margin of static value
-///
-/// the 32 bits of the data field are so defined
-///
-/// bit  0-15: move
-/// bit 16-20: not used
-/// bit 21-22: value type
-/// bit 23-31: generation
+/// key        32 bit
+/// move       16 bit
+/// bound type  8 bit
+/// generation  8 bit
+/// value      16 bit
+/// depth      16 bit
+/// eval value 16 bit
 
-class TTEntry {
+struct TTEntry {
 
-public:
-  void save(uint32_t k, Value v, Bound b, Depth d, Move m, int g, Value statV, Value statM) {
-
-    key32        = (uint32_t)k;
-    move16       = (uint16_t)m;
-    bound        = (uint8_t)b;
-    generation8  = (uint8_t)g;
-    value16      = (int16_t)v;
-    depth16      = (int16_t)d;
-    staticValue  = (int16_t)statV;
-    staticMargin = (int16_t)statM;
-  }
-  void set_generation(int g) { generation8 = (uint8_t)g; }
-
-  uint32_t key() const              { return key32; }
-  Depth depth() const               { return (Depth)depth16; }
-  Move move() const                 { return (Move)move16; }
-  Value value() const               { return (Value)value16; }
-  Bound type() const                { return (Bound)bound; }
-  int generation() const            { return (int)generation8; }
-  Value static_value() const        { return (Value)staticValue; }
-  Value static_value_margin() const { return (Value)staticMargin; }
+  Move  move()  const      { return (Move )move16; }
+  Bound bound() const      { return (Bound)bound8; }
+  Value value() const      { return (Value)value16; }
+  Depth depth() const      { return (Depth)depth16; }
+  Value eval_value() const { return (Value)evalValue; }
 
 private:
+  friend class TranspositionTable;
+
+  void save(uint32_t k, Value v, Bound b, Depth d, Move m, uint8_t g, Value ev) {
+
+    key32       = (uint32_t)k;
+    move16      = (uint16_t)m;
+    bound8      = (uint8_t)b;
+    generation8 = (uint8_t)g;
+    value16     = (int16_t)v;
+    depth16     = (int16_t)d;
+    evalValue   = (int16_t)ev;
+  }
+
   uint32_t key32;
   uint16_t move16;
-  uint8_t bound, generation8;
-  int16_t value16, depth16, staticValue, staticMargin;
+  uint8_t bound8, generation8;
+  int16_t value16, depth16, evalValue;
 };
 
 
-/// This is the number of TTEntry slots for each cluster
-const int ClusterSize = 4;
-
-
-/// TTCluster consists of ClusterSize number of TTEntries. Size of TTCluster
-/// must not be bigger than a cache line size. In case it is less, it should
-/// be padded to guarantee always aligned accesses.
-
-struct TTCluster {
-  TTEntry data[ClusterSize];
-};
-
-
-/// The transposition table class. This is basically just a huge array containing
-/// TTCluster objects, and a few methods for writing and reading entries.
+/// A TranspositionTable consists of a power of 2 number of clusters and each
+/// cluster consists of ClusterSize number of TTEntry. Each non-empty entry
+/// contains information of exactly one position. The size of a cluster should
+/// not be bigger than a cache line size. In case it is less, it should be padded
+/// to guarantee always aligned accesses.
 
 class TranspositionTable {
 
-  TranspositionTable(const TranspositionTable&);
-  TranspositionTable& operator=(const TranspositionTable&);
+  static const unsigned ClusterSize = 4;
 
 public:
-  TranspositionTable();
-  ~TranspositionTable();
-  void set_size(size_t mbSize);
+ ~TranspositionTable() { free(mem); }
+  void new_search() { ++generation; }
+
+  const TTEntry* probe(const Key key) const;
+  TTEntry* first_entry(const Key key) const;
+  void resize(uint64_t mbSize);
   void clear();
-  void store(const Key posKey, Value v, Bound type, Depth d, Move m, Value statV, Value kingD);
-  TTEntry* probe(const Key posKey) const;
-  void new_search();
-  TTEntry* first_entry(const Key posKey) const;
-  void refresh(const TTEntry* tte) const;
+  void store(const Key key, Value v, Bound type, Depth d, Move m, Value statV);
 
 private:
-  size_t size;
-  TTCluster* entries;
-  uint8_t generation; // Size must be not bigger then TTEntry::generation8
+  uint32_t hashMask;
+  TTEntry* table;
+  void* mem;
+  uint8_t generation; // Size must be not bigger than TTEntry::generation8
 };
 
 extern TranspositionTable TT;
@@ -119,18 +96,9 @@ extern TranspositionTable TT;
 /// a cluster given a position. The lowest order bits of the key are used to
 /// get the index of the cluster.
 
-inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
+inline TTEntry* TranspositionTable::first_entry(const Key key) const {
 
-  return entries[((uint32_t)posKey) & (size - 1)].data;
+  return table + ((uint32_t)key & hashMask);
 }
 
-
-/// TranspositionTable::refresh() updates the 'generation' value of the TTEntry
-/// to avoid aging. Normally called after a TT hit.
-
-inline void TranspositionTable::refresh(const TTEntry* tte) const {
-
-  const_cast<TTEntry*>(tte)->set_generation(generation);
-}
-
-#endif // !defined(TT_H_INCLUDED)
+#endif // #ifndef TT_H_INCLUDED

src/types.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(TYPES_H_INCLUDED)
+#ifndef TYPES_H_INCLUDED
 #define TYPES_H_INCLUDED
 
 /// For Linux and OSX configuration is done automatically using Makefile. To get
@@ -26,7 +26,7 @@
 /// For Windows, part of the configuration is detected automatically, but some
 /// switches need to be set manually:
 ///
-/// -DNDEBUG      | Disable debugging mode. Use always.
+/// -DNDEBUG      | Disable debugging mode. Always use this.
 ///
 /// -DNO_PREFETCH | Disable use of prefetch asm-instruction. A must if you want
 ///               | the executable to run on some very old machines.
@@ -35,13 +35,16 @@
 ///               | only in 64-bit mode. For compiling requires hardware with
 ///               | popcnt support.
 
+#include <cassert>
 #include <cctype>
 #include <climits>
 #include <cstdlib>
 
 #include "platform.h"
 
-#if defined(_WIN64)
+#define unlikely(x) (x) // For code annotation purposes
+
+#if defined(_WIN64) && !defined(IS_64BIT)
 #  include <intrin.h> // MSVC popcnt and bsfq instrinsics
 #  define IS_64BIT
 #  define USE_BSFQ
@@ -51,13 +54,24 @@
 #  include <nmmintrin.h> // Intel header for _mm_popcnt_u64() intrinsic
 #endif
 
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#  define CACHE_LINE_ALIGNMENT __declspec(align(64))
+#if defined(USE_PEXT)
+#  include <immintrin.h> // Header for _pext_u64() intrinsic
 #else
-#  define CACHE_LINE_ALIGNMENT  __attribute__ ((aligned(64)))
+#  define _pext_u64(b, m) (0)
 #endif
 
-#if defined(_MSC_VER)
+#  if !defined(NO_PREFETCH) && (defined(__INTEL_COMPILER) || defined(_MSC_VER))
+#   include <xmmintrin.h> // Intel and Microsoft header for _mm_prefetch()
+#  endif
+
+#define CACHE_LINE_SIZE 64
+#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
+#  define CACHE_LINE_ALIGNMENT __declspec(align(CACHE_LINE_SIZE))
+#else
+#  define CACHE_LINE_ALIGNMENT  __attribute__ ((aligned(CACHE_LINE_SIZE)))
+#endif
+
+#ifdef _MSC_VER
 #  define FORCE_INLINE  __forceinline
 #elif defined(__GNUC__)
 #  define FORCE_INLINE  inline __attribute__((always_inline))
@@ -65,13 +79,19 @@
 #  define FORCE_INLINE  inline
 #endif
 
-#if defined(USE_POPCNT)
+#ifdef USE_POPCNT
 const bool HasPopCnt = true;
 #else
 const bool HasPopCnt = false;
 #endif
 
-#if defined(IS_64BIT)
+#ifdef USE_PEXT
+const bool HasPext = true;
+#else
+const bool HasPext = false;
+#endif
+
+#ifdef IS_64BIT
 const bool Is64Bit = true;
 #else
 const bool Is64Bit = false;
@@ -80,87 +100,86 @@ const bool Is64Bit = false;
 typedef uint64_t Key;
 typedef uint64_t Bitboard;
 
-const int MAX_MOVES      = 192;
-const int MAX_PLY        = 100;
-const int MAX_PLY_PLUS_2 = MAX_PLY + 2;
-
-const Bitboard FileABB = 0x0101010101010101ULL;
-const Bitboard FileBBB = FileABB << 1;
-const Bitboard FileCBB = FileABB << 2;
-const Bitboard FileDBB = FileABB << 3;
-const Bitboard FileEBB = FileABB << 4;
-const Bitboard FileFBB = FileABB << 5;
-const Bitboard FileGBB = FileABB << 6;
-const Bitboard FileHBB = FileABB << 7;
-
-const Bitboard Rank1BB = 0xFF;
-const Bitboard Rank2BB = Rank1BB << (8 * 1);
-const Bitboard Rank3BB = Rank1BB << (8 * 2);
-const Bitboard Rank4BB = Rank1BB << (8 * 3);
-const Bitboard Rank5BB = Rank1BB << (8 * 4);
-const Bitboard Rank6BB = Rank1BB << (8 * 5);
-const Bitboard Rank7BB = Rank1BB << (8 * 6);
-const Bitboard Rank8BB = Rank1BB << (8 * 7);
-
+const int MAX_MOVES      = 256;
+const int MAX_PLY        = 120;
+const int MAX_PLY_PLUS_6 = MAX_PLY + 6;
 
 /// 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), castle (3)
+/// 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 {
-  MOVE_NONE = 0,
+  MOVE_NONE,
   MOVE_NULL = 65
 };
 
 enum MoveType {
-  NORMAL    = 0,
+  NORMAL,
   PROMOTION = 1 << 14,
   ENPASSANT = 2 << 14,
-  CASTLE    = 3 << 14
+  CASTLING  = 3 << 14
 };
 
-enum CastleRight {  // Defined as in PolyGlot book hash key
-  CASTLES_NONE = 0,
-  WHITE_OO     = 1,
-  WHITE_OOO    = 2,
-  BLACK_OO     = 4,
-  BLACK_OOO    = 8,
-  ALL_CASTLES  = 15
+enum Color {
+  WHITE, BLACK, NO_COLOR, COLOR_NB = 2
 };
 
 enum CastlingSide {
-  KING_SIDE,
-  QUEEN_SIDE
+  KING_SIDE, QUEEN_SIDE, CASTLING_SIDE_NB = 2
+};
+
+enum CastlingRight {  // Defined as in PolyGlot book hash key
+  NO_CASTLING,
+  WHITE_OO,
+  WHITE_OOO   = WHITE_OO << 1,
+  BLACK_OO    = WHITE_OO << 2,
+  BLACK_OOO   = WHITE_OO << 3,
+  ANY_CASTLING = WHITE_OO | WHITE_OOO | BLACK_OO | BLACK_OOO,
+  CASTLING_RIGHT_NB = 16
+};
+
+template<Color C, CastlingSide S> struct MakeCastling {
+  static const CastlingRight
+  right = C == WHITE ? S == QUEEN_SIDE ? WHITE_OOO : WHITE_OO
+                     : S == QUEEN_SIDE ? BLACK_OOO : BLACK_OO;
+};
+
+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
+  SCALE_FACTOR_DRAW    = 0,
+  SCALE_FACTOR_ONEPAWN = 48,
+  SCALE_FACTOR_NORMAL  = 64,
+  SCALE_FACTOR_MAX     = 128,
+  SCALE_FACTOR_NONE    = 255
 };
 
 enum Bound {
-  BOUND_NONE  = 0,
-  BOUND_UPPER = 1,
-  BOUND_LOWER = 2,
+  BOUND_NONE,
+  BOUND_UPPER,
+  BOUND_LOWER,
   BOUND_EXACT = BOUND_UPPER | BOUND_LOWER
 };
 
 enum Value {
   VALUE_ZERO      = 0,
   VALUE_DRAW      = 0,
-  VALUE_KNOWN_WIN = 15000,
-  VALUE_MATE      = 30000,
-  VALUE_INFINITE  = 30001,
-  VALUE_NONE      = 30002,
+  VALUE_KNOWN_WIN = 10000,
+  VALUE_MATE      = 32000,
+  VALUE_INFINITE  = 32001,
+  VALUE_NONE      = 32002,
 
   VALUE_MATE_IN_MAX_PLY  =  VALUE_MATE - MAX_PLY,
   VALUE_MATED_IN_MAX_PLY = -VALUE_MATE + MAX_PLY,
@@ -168,28 +187,26 @@ enum Value {
   VALUE_ENSURE_INTEGER_SIZE_P = INT_MAX,
   VALUE_ENSURE_INTEGER_SIZE_N = INT_MIN,
 
-  Mg = 0, Eg = 1,
-
   PawnValueMg   = 198,   PawnValueEg   = 258,
   KnightValueMg = 817,   KnightValueEg = 846,
   BishopValueMg = 836,   BishopValueEg = 857,
   RookValueMg   = 1270,  RookValueEg   = 1278,
-  QueenValueMg  = 2521,  QueenValueEg  = 2558
+  QueenValueMg  = 2521,  QueenValueEg  = 2558,
+
+  MidgameLimit  = 15581, EndgameLimit  = 3998
 };
 
 enum PieceType {
-  NO_PIECE_TYPE = 0, ALL_PIECES = 0,
-  PAWN = 1, KNIGHT = 2, BISHOP = 3, ROOK = 4, QUEEN = 5, KING = 6
+  NO_PIECE_TYPE, PAWN, KNIGHT, BISHOP, ROOK, QUEEN, KING,
+  ALL_PIECES = 0,
+  PIECE_TYPE_NB = 8
 };
 
 enum Piece {
-  NO_PIECE = 16, // color_of(NO_PIECE) == NO_COLOR
-  W_PAWN = 1, W_KNIGHT =  2, W_BISHOP =  3, W_ROOK =  4, W_QUEEN =  5, W_KING =  6,
-  B_PAWN = 9, B_KNIGHT = 10, B_BISHOP = 11, B_ROOK = 12, B_QUEEN = 13, B_KING = 14
-};
-
-enum Color {
-  WHITE, BLACK, NO_COLOR
+  NO_PIECE,
+  W_PAWN = 1, W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING,
+  B_PAWN = 9, B_KNIGHT, B_BISHOP, B_ROOK, B_QUEEN, B_KING,
+  PIECE_NB = 16
 };
 
 enum Depth {
@@ -197,8 +214,8 @@ enum Depth {
   ONE_PLY = 2,
 
   DEPTH_ZERO          =  0 * ONE_PLY,
-  DEPTH_QS_CHECKS     = -1 * ONE_PLY,
-  DEPTH_QS_NO_CHECKS  = -2 * ONE_PLY,
+  DEPTH_QS_CHECKS     =  0 * ONE_PLY,
+  DEPTH_QS_NO_CHECKS  = -1 * ONE_PLY,
   DEPTH_QS_RECAPTURES = -5 * ONE_PLY,
 
   DEPTH_NONE = -127 * ONE_PLY
@@ -215,6 +232,8 @@ enum Square {
   SQ_A8, SQ_B8, SQ_C8, SQ_D8, SQ_E8, SQ_F8, SQ_G8, SQ_H8,
   SQ_NONE,
 
+  SQUARE_NB = 64,
+
   DELTA_N =  8,
   DELTA_E =  1,
   DELTA_S = -8,
@@ -229,76 +248,85 @@ enum Square {
 };
 
 enum File {
-  FILE_A, FILE_B, FILE_C, FILE_D, FILE_E, FILE_F, FILE_G, FILE_H
+  FILE_A, FILE_B, FILE_C, FILE_D, FILE_E, FILE_F, FILE_G, FILE_H, FILE_NB
 };
 
 enum Rank {
-  RANK_1, RANK_2, RANK_3, RANK_4, RANK_5, RANK_6, RANK_7, RANK_8
+  RANK_1, RANK_2, RANK_3, RANK_4, RANK_5, RANK_6, RANK_7, RANK_8, RANK_NB
 };
 
 
-/// Score enum keeps a midgame and an endgame value in a single integer (enum),
-/// first LSB 16 bits are used to store endgame value, while upper bits are used
-/// for midgame value. Compiler is free to choose the enum type as long as can
-/// keep its data, so ensure Score to be an integer type.
+/// The Score enum stores a middlegame and an endgame value in a single integer
+/// (enum). The least significant 16 bits are used to store the endgame value
+/// and the upper 16 bits are used to store the middlegame value. The compiler
+/// is free to choose the enum type as long as it can store the data, so we
+/// ensure that Score is an integer type by assigning some big int values.
 enum Score {
-  SCORE_ZERO = 0,
+  SCORE_ZERO,
   SCORE_ENSURE_INTEGER_SIZE_P = INT_MAX,
   SCORE_ENSURE_INTEGER_SIZE_N = INT_MIN
 };
 
-inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); }
+typedef union {
+  uint32_t full;
+  struct { int16_t eg, mg; } half;
+} ScoreView;
 
-/// Extracting the signed lower and upper 16 bits it 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 mg_value(Score s) { return Value(((s + 32768) & ~0xffff) / 0x10000); }
-
-/// On Intel 64 bit we have a small speed regression with the standard conforming
-/// version, so use a faster code in this case that, although not 100% standard
-/// compliant it seems to work for Intel and MSVC.
-#if defined(IS_64BIT) && (!defined(__GNUC__) || defined(__INTEL_COMPILER))
-
-inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
-
-#else
-
-inline Value eg_value(Score s) {
-  return Value((int)(unsigned(s) & 0x7fffu) - (int)(unsigned(s) & 0x8000u));
+inline Score make_score(int mg, int eg) {
+  ScoreView v;
+  v.half.mg = (int16_t)(mg - (uint16_t(eg) >> 15));
+  v.half.eg = (int16_t)eg;
+  return Score(v.full);
 }
 
-#endif
+inline Value mg_value(Score s) {
+  ScoreView v;
+  v.full = s;
+  return Value(v.half.mg + (uint16_t(v.half.eg) >> 15));
+}
 
-#define ENABLE_SAFE_OPERATORS_ON(T)                                         \
+inline Value eg_value(Score s) {
+  ScoreView v;
+  v.full = s;
+  return Value(v.half.eg);
+}
+
+#define ENABLE_BASE_OPERATORS_ON(T)                                         \
 inline T operator+(const T d1, const T d2) { return T(int(d1) + int(d2)); } \
 inline T operator-(const T d1, const T d2) { return T(int(d1) - int(d2)); } \
 inline T operator*(int i, const T d) { return T(i * int(d)); }              \
 inline T operator*(const T d, int i) { return T(int(d) * i); }              \
 inline T operator-(const T d) { return T(-int(d)); }                        \
-inline T& operator+=(T& d1, const T d2) { d1 = d1 + d2; return d1; }        \
-inline T& operator-=(T& d1, const T d2) { d1 = d1 - d2; return d1; }        \
-inline T& operator*=(T& d, int i) { d = T(int(d) * i); return d; }
+inline T& operator+=(T& d1, const T d2) { return d1 = d1 + d2; }            \
+inline T& operator-=(T& d1, const T d2) { return d1 = d1 - d2; }            \
+inline T& operator*=(T& d, int i) { return d = T(int(d) * i); }
 
-#define ENABLE_OPERATORS_ON(T) ENABLE_SAFE_OPERATORS_ON(T)                  \
-inline T operator++(T& d, int) { d = T(int(d) + 1); return d; }             \
-inline T operator--(T& d, int) { d = T(int(d) - 1); return d; }             \
+ENABLE_BASE_OPERATORS_ON(Score)
+
+#define ENABLE_FULL_OPERATORS_ON(T)                                         \
+ENABLE_BASE_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); }                    \
 inline T operator/(const T d, int i) { return T(int(d) / i); }              \
-inline T& operator/=(T& d, int i) { d = T(int(d) / i); return d; }
+inline T& operator/=(T& d, int i) { return d = T(int(d) / i); }
 
-ENABLE_OPERATORS_ON(Value)
-ENABLE_OPERATORS_ON(PieceType)
-ENABLE_OPERATORS_ON(Piece)
-ENABLE_OPERATORS_ON(Color)
-ENABLE_OPERATORS_ON(Depth)
-ENABLE_OPERATORS_ON(Square)
-ENABLE_OPERATORS_ON(File)
-ENABLE_OPERATORS_ON(Rank)
+ENABLE_FULL_OPERATORS_ON(Value)
+ENABLE_FULL_OPERATORS_ON(PieceType)
+ENABLE_FULL_OPERATORS_ON(Piece)
+ENABLE_FULL_OPERATORS_ON(Color)
+ENABLE_FULL_OPERATORS_ON(Depth)
+ENABLE_FULL_OPERATORS_ON(Square)
+ENABLE_FULL_OPERATORS_ON(File)
+ENABLE_FULL_OPERATORS_ON(Rank)
 
-/// Added operators for adding integers to a Value
+#undef ENABLE_FULL_OPERATORS_ON
+#undef ENABLE_BASE_OPERATORS_ON
+
+/// Additional operators to add integers to a Value
 inline Value operator+(Value v, int i) { return Value(int(v) + i); }
 inline Value operator-(Value v, int i) { return Value(int(v) - i); }
-
-ENABLE_SAFE_OPERATORS_ON(Score)
+inline Value& operator+=(Value& v, int i) { return v = v + i; }
+inline Value& operator-=(Value& v, int i) { return v = v - i; }
 
 /// 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.
@@ -309,51 +337,27 @@ inline Score operator/(Score s, int i) {
   return make_score(mg_value(s) / i, eg_value(s) / i);
 }
 
-/// Weight score v by score w trying to prevent overflow
-inline Score apply_weight(Score v, Score w) {
-  return make_score((int(mg_value(v)) * mg_value(w)) / 0x100,
-                    (int(eg_value(v)) * eg_value(w)) / 0x100);
-}
+extern Value PieceValue[PHASE_NB][PIECE_NB];
 
-#undef ENABLE_OPERATORS_ON
-#undef ENABLE_SAFE_OPERATORS_ON
-
-namespace Zobrist {
-
-  extern Key psq[2][8][64]; // [color][pieceType][square / piece count]
-  extern Key enpassant[8];  // [file]
-  extern Key castle[16];    // [castleRight]
-  extern Key side;
-  extern Key exclusion;
-
-  void init();
-}
-
-CACHE_LINE_ALIGNMENT
-
-extern Score pieceSquareTable[16][64]; // [piece][square]
-extern Value PieceValue[2][18];        // [Mg / Eg][piece / pieceType]
-extern int SquareDistance[64][64];     // [square][square]
-
-struct MoveStack {
+struct ExtMove {
   Move move;
-  int score;
+  Value value;
 };
 
-inline bool operator<(const MoveStack& f, const MoveStack& s) {
-  return f.score < s.score;
+inline bool operator<(const ExtMove& f, const ExtMove& s) {
+  return f.value < s.value;
 }
 
 inline Color operator~(Color c) {
-  return Color(c ^ 1);
+  return Color(c ^ BLACK);
 }
 
 inline Square operator~(Square s) {
-  return Square(s ^ 56); // Vertical flip SQ_A1 -> SQ_A8
+  return Square(s ^ SQ_A8); // Vertical flip SQ_A1 -> SQ_A8
 }
 
-inline Square operator|(File f, Rank r) {
-  return Square((r << 3) | f);
+inline CastlingRight operator|(Color c, CastlingSide s) {
+  return CastlingRight(WHITE_OO << ((s == QUEEN_SIDE) + 2 * c));
 }
 
 inline Value mate_in(int ply) {
@@ -364,20 +368,21 @@ inline Value mated_in(int ply) {
   return -VALUE_MATE + ply;
 }
 
+inline Square make_square(File f, Rank r) {
+  return Square((r << 3) | f);
+}
+
 inline Piece make_piece(Color c, PieceType pt) {
   return Piece((c << 3) | pt);
 }
 
-inline CastleRight make_castle_right(Color c, CastlingSide s) {
-  return CastleRight(WHITE_OO << ((s == QUEEN_SIDE) + 2 * c));
+inline PieceType type_of(Piece pc)  {
+  return PieceType(pc & 7);
 }
 
-inline PieceType type_of(Piece p)  {
-  return PieceType(p & 7);
-}
-
-inline Color color_of(Piece p) {
-  return Color(p >> 3);
+inline Color color_of(Piece pc) {
+  assert(pc != NO_PIECE);
+  return Color(pc >> 3);
 }
 
 inline bool is_ok(Square s) {
@@ -392,10 +397,6 @@ inline Rank rank_of(Square s) {
   return Rank(s >> 3);
 }
 
-inline Square mirror(Square s) {
-  return Square(s ^ 7); // Horizontal flip SQ_A1 -> SQ_H1
-}
-
 inline Square relative_square(Color c, Square s) {
   return Square(s ^ (c * 56));
 }
@@ -413,24 +414,12 @@ inline bool opposite_colors(Square s1, Square s2) {
   return ((s >> 3) ^ s) & 1;
 }
 
-inline int file_distance(Square s1, Square s2) {
-  return abs(file_of(s1) - file_of(s2));
+inline char to_char(File f, bool tolower = true) {
+  return char(f - FILE_A + (tolower ? 'a' : 'A'));
 }
 
-inline int rank_distance(Square s1, Square s2) {
-  return abs(rank_of(s1) - rank_of(s2));
-}
-
-inline int square_distance(Square s1, Square s2) {
-  return SquareDistance[s1][s2];
-}
-
-inline char file_to_char(File f) {
-  return char(f - FILE_A + int('a'));
-}
-
-inline char rank_to_char(Rank r) {
-  return char(r - RANK_1 + int('1'));
+inline char to_char(Rank r) {
+  return char(r - RANK_1 + '1');
 }
 
 inline Square pawn_push(Color c) {
@@ -459,7 +448,7 @@ inline Move make_move(Square from, Square to) {
 
 template<MoveType T>
 inline Move make(Square from, Square to, PieceType pt = KNIGHT) {
-  return Move(to | (from << 6) | T | ((pt - KNIGHT) << 12)) ;
+  return Move(to | (from << 6) | T | ((pt - KNIGHT) << 12));
 }
 
 inline bool is_ok(Move m) {
@@ -468,26 +457,9 @@ inline bool is_ok(Move m) {
 
 #include <string>
 
-inline const std::string square_to_string(Square s) {
-  char ch[] = { file_to_char(file_of(s)), rank_to_char(rank_of(s)), 0 };
+inline const std::string to_string(Square s) {
+  char ch[] = { to_char(file_of(s)), to_char(rank_of(s)), 0 };
   return ch;
 }
 
-/// Our insertion sort implementation, works with pointers and iterators and is
-/// guaranteed to be stable, as is needed.
-template<typename T, typename K>
-void sort(K first, K last)
-{
-  T tmp;
-  K p, q;
-
-  for (p = first + 1; p < last; p++)
-  {
-      tmp = *p;
-      for (q = p; q != first && *(q-1) < tmp; --q)
-          *q = *(q-1);
-      *q = tmp;
-  }
-}
-
-#endif // !defined(TYPES_H_INCLUDED)
+#endif // #ifndef TYPES_H_INCLUDED

src/uci.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <iomanip>
 #include <iostream>
 #include <sstream>
 #include <string>
@@ -26,6 +27,7 @@
 #include "position.h"
 #include "search.h"
 #include "thread.h"
+#include "tt.h"
 #include "ucioption.h"
 
 using namespace std;
@@ -37,125 +39,18 @@ namespace {
   // FEN string of the initial position, normal chess
   const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
 
-  // Keep track of position keys along the setup moves (from start position to the
-  // position just before to start searching). Needed by repetition draw detection.
+  // Keep a track of the position keys along the setup moves (from the start position
+  // to the position just before the search starts). This is needed by the repetition
+  // draw detection code.
   Search::StateStackPtr SetupStates;
 
-  void set_option(istringstream& up);
-  void set_position(Position& pos, istringstream& up);
-  void go(Position& pos, istringstream& up);
-}
 
-
-/// Wait for a command from the user, parse this text string as an UCI command,
-/// and call the appropriate functions. Also intercepts EOF from stdin to ensure
-/// that we exit gracefully if the GUI dies unexpectedly. In addition to the UCI
-/// commands, the function also supports a few debug commands.
-
-void UCI::loop(const string& args) {
-
-  Position pos(StartFEN, false, Threads.main_thread()); // The root position
-  string cmd, token;
-
-  while (token != "quit")
-  {
-      if (!args.empty())
-          cmd = args;
-
-      else if (!getline(cin, cmd)) // Block here waiting for input
-          cmd = "quit";
-
-      istringstream is(cmd);
-
-      is >> skipws >> token;
-
-      if (token == "quit" || token == "stop")
-      {
-          Search::Signals.stop = true;
-          Threads.wait_for_search_finished(); // Cannot quit while threads are running
-      }
-
-      else if (token == "ponderhit")
-      {
-          // The opponent has played the expected move. GUI sends "ponderhit" if
-          // we were told to ponder on the same move the opponent has played. We
-          // should continue searching but switching from pondering to normal search.
-          Search::Limits.ponder = false;
-
-          if (Search::Signals.stopOnPonderhit)
-          {
-              Search::Signals.stop = true;
-              Threads.main_thread()->wake_up(); // Could be sleeping
-          }
-      }
-
-      else if (token == "go")
-          go(pos, is);
-
-      else if (token == "ucinewgame")
-      { /* Avoid returning "Unknown command" */ }
-
-      else if (token == "isready")
-          sync_cout << "readyok" << sync_endl;
-
-      else if (token == "position")
-          set_position(pos, is);
-
-      else if (token == "setoption")
-          set_option(is);
-
-      else if (token == "d")
-          pos.print();
-
-      else if (token == "flip")
-          pos.flip();
-
-      else if (token == "eval")
-          sync_cout << Eval::trace(pos) << sync_endl;
-
-      else if (token == "bench")
-          benchmark(pos, is);
-
-      else if (token == "key")
-          sync_cout << "key: " << hex     << pos.key()
-                    << "\nmaterial key: " << pos.material_key()
-                    << "\npawn key: "     << pos.pawn_key() << sync_endl;
-
-      else if (token == "uci")
-          sync_cout << "id name " << engine_info(true)
-                    << "\n"       << Options
-                    << "\nuciok"  << sync_endl;
-
-      else if (token == "perft" && (is >> token)) // Read depth
-      {
-          stringstream ss;
-
-          ss << Options["Hash"]    << " "
-             << Options["Threads"] << " " << token << " current perft";
-
-          benchmark(pos, ss);
-      }
-
-      else
-          sync_cout << "Unknown command: " << cmd << sync_endl;
-
-      if (!args.empty()) // Command line arguments have one-shot behaviour
-      {
-          Threads.wait_for_search_finished();
-          break;
-      }
-  }
-}
-
-
-namespace {
-
-  // set_position() is called when engine receives the "position" UCI command.
-  // The function sets up the position described in the given fen string ("fen")
+  // position() is called when engine receives the "position" UCI command.
+  // The function sets up the position described in the given FEN string ("fen")
   // or the starting position ("startpos") and then makes the moves given in the
   // following move list ("moves").
 
-  void set_position(Position& pos, istringstream& is) {
+  void position(Position& pos, istringstream& is) {
 
     Move m;
     string token, fen;
@@ -173,7 +68,7 @@ namespace {
     else
         return;
 
-    pos.from_fen(fen, Options["UCI_Chess960"], Threads.main_thread());
+    pos.set(fen, Options["UCI_Chess960"], Threads.main());
     SetupStates = Search::StateStackPtr(new std::stack<StateInfo>());
 
     // Parse move list (if any)
@@ -185,10 +80,10 @@ namespace {
   }
 
 
-  // set_option() is called when engine receives the "setoption" UCI command. The
+  // setoption() is called when engine receives the "setoption" UCI command. The
   // function updates the UCI option ("name") to the given value ("value").
 
-  void set_option(istringstream& is) {
+  void setoption(istringstream& is) {
 
     string token, name, value;
 
@@ -210,42 +105,115 @@ namespace {
 
 
   // go() is called when engine receives the "go" UCI command. The function sets
-  // the thinking time and other parameters from the input string, and then starts
+  // the thinking time and other parameters from the input string, and starts
   // the search.
 
-  void go(Position& pos, istringstream& is) {
+  void go(const Position& pos, istringstream& is) {
 
     Search::LimitsType limits;
-    vector<Move> searchMoves;
     string token;
 
     while (is >> token)
     {
-        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 == "infinite")
-            limits.infinite = true;
-        else if (token == "ponder")
-            limits.ponder = true;
-        else if (token == "searchmoves")
+        if (token == "searchmoves")
             while (is >> token)
-                searchMoves.push_back(move_from_uci(pos, token));
+                limits.searchmoves.push_back(move_from_uci(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 == "infinite")  limits.infinite = true;
+        else if (token == "ponder")    limits.ponder = true;
     }
 
-    Threads.start_searching(pos, limits, searchMoves, SetupStates);
+    Threads.start_thinking(pos, limits, SetupStates);
   }
+
+} // namespace
+
+
+/// Wait for a command from the user, parse this text string as an UCI command,
+/// and call the appropriate functions. Also intercepts EOF from stdin to ensure
+/// that we exit gracefully if the GUI dies unexpectedly. In addition to the UCI
+/// commands, the function also supports a few debug commands.
+
+void UCI::loop(int argc, char* argv[]) {
+
+  Position pos(StartFEN, false, Threads.main()); // The root position
+  string token, cmd;
+
+  for (int i = 1; i < argc; ++i)
+      cmd += std::string(argv[i]) + " ";
+
+  do {
+      if (argc == 1 && !getline(cin, cmd)) // Block here waiting for input
+          cmd = "quit";
+
+      istringstream is(cmd);
+
+      is >> skipws >> token;
+
+      if (token == "quit" || token == "stop" || token == "ponderhit")
+      {
+          // The GUI sends 'ponderhit' to tell us to ponder on the same move the
+          // opponent has played. In case Signals.stopOnPonderhit is set we are
+          // waiting for 'ponderhit' to stop the search (for instance because we
+          // already ran out of time), otherwise we should continue searching but
+          // switch from pondering to normal search.
+          if (token != "ponderhit" || Search::Signals.stopOnPonderhit)
+          {
+              Search::Signals.stop = true;
+              Threads.main()->notify_one(); // Could be sleeping
+          }
+          else
+              Search::Limits.ponder = false;
+      }
+      else if (token == "perft" || token == "divide")
+      {
+          int depth;
+          stringstream ss;
+
+          is >> depth;
+          ss << Options["Hash"]    << " "
+             << Options["Threads"] << " " << depth << " current " << token;
+
+          benchmark(pos, ss);
+      }
+      else if (token == "key")
+          sync_cout << hex << uppercase << setfill('0')
+                    << "position key: "   << setw(16) << pos.key()
+                    << "\nmaterial key: " << setw(16) << pos.material_key()
+                    << "\npawn key:     " << setw(16) << pos.pawn_key()
+                    << dec << nouppercase << setfill(' ') << sync_endl;
+
+      else if (token == "uci")
+          sync_cout << "id name " << engine_info(true)
+                    << "\n"       << Options
+                    << "\nuciok"  << sync_endl;
+
+      else if (token == "eval")
+      {
+          Search::RootColor = pos.side_to_move(); // Ensure it is set
+          sync_cout << Eval::trace(pos) << sync_endl;
+      }
+      else if (token == "ucinewgame") { /* Avoid returning "Unknown command" */ }
+      else if (token == "go")         go(pos, is);
+      else if (token == "position")   position(pos, is);
+      else if (token == "setoption")  setoption(is);
+      else if (token == "flip")       pos.flip();
+      else if (token == "bench")      benchmark(pos, is);
+      else if (token == "d")          sync_cout << pos.pretty() << sync_endl;
+      else if (token == "isready")    sync_cout << "readyok" << sync_endl;
+      else
+          sync_cout << "Unknown command: " << cmd << sync_endl;
+
+  } while (token != "quit" && argc == 1); // Passed args have one-shot behaviour
+
+  Threads.wait_for_think_finished(); // Cannot quit whilst the search is running
 }

src/ucioption.cpp

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -38,7 +38,7 @@ namespace UCI {
 void on_logger(const Option& o) { start_logger(o); }
 void on_eval(const Option&) { Eval::init(); }
 void on_threads(const Option&) { Threads.read_uci_options(); }
-void on_hash_size(const Option& o) { TT.set_size(o); }
+void on_hash_size(const Option& o) { TT.resize(o); }
 void on_clear_hash(const Option&) { TT.clear(); }
 
 
@@ -50,44 +50,39 @@ bool CaseInsensitiveLess::operator() (const string& s1, const string& s2) const
 }
 
 
-/// init() initializes the UCI options to their hard coded default values
-/// and initializes the default value of "Threads" and "Min Split Depth"
-/// parameters according to the number of CPU cores detected.
+/// init() initializes the UCI options to their hard-coded default values
 
 void init(OptionsMap& o) {
 
-  int cpus = std::min(cpu_count(), MAX_THREADS);
-  int msd = cpus < 8 ? 4 : 7;
-
-  o["Use Debug Log"]               = Option(false, on_logger);
-  o["Use Search Log"]              = Option(false);
-  o["Search Log Filename"]         = Option("SearchLog.txt");
-  o["Book File"]                   = Option("book.bin");
-  o["Best Book Move"]              = Option(false);
-  o["Mobility (Middle Game)"]      = Option(100, 0, 200, on_eval);
-  o["Mobility (Endgame)"]          = Option(100, 0, 200, on_eval);
-  o["Passed Pawns (Middle Game)"]  = Option(100, 0, 200, on_eval);
-  o["Passed Pawns (Endgame)"]      = Option(100, 0, 200, on_eval);
-  o["Space"]                       = Option(100, 0, 200, on_eval);
-  o["Aggressiveness"]              = Option(100, 0, 200, on_eval);
-  o["Cowardice"]                   = Option(100, 0, 200, on_eval);
-  o["Min Split Depth"]             = Option(msd, 4, 7, on_threads);
-  o["Max Threads per Split Point"] = Option(5, 4, 8, on_threads);
-  o["Threads"]                     = Option(cpus, 1, MAX_THREADS, on_threads);
-  o["Use Sleeping Threads"]        = Option(false, on_threads);
-  o["Hash"]                        = Option(32, 4, 8192, on_hash_size);
-  o["Clear Hash"]                  = Option(on_clear_hash);
-  o["Ponder"]                      = Option(true);
-  o["OwnBook"]                     = Option(false);
-  o["MultiPV"]                     = Option(1, 1, 500);
-  o["Skill Level"]                 = Option(20, 0, 20);
-  o["Emergency Move Horizon"]      = Option(40, 0, 50);
-  o["Emergency Base Time"]         = Option(200, 0, 30000);
-  o["Emergency Move Time"]         = Option(70, 0, 5000);
-  o["Minimum Thinking Time"]       = Option(20, 0, 5000);
-  o["Slow Mover"]                  = Option(100, 10, 1000);
-  o["UCI_Chess960"]                = Option(false);
-  o["UCI_AnalyseMode"]             = Option(false, on_eval);
+  o["Write Debug Log"]          << Option(false, on_logger);
+  o["Write Search Log"]         << Option(false);
+  o["Search Log Filename"]      << Option("SearchLog.txt");
+  o["Book File"]                << Option("book.bin");
+  o["Best Book Move"]           << Option(false);
+  o["Contempt Factor"]          << Option(0, -50,  50);
+  o["Mobility (Midgame)"]       << Option(100, 0, 200, on_eval);
+  o["Mobility (Endgame)"]       << Option(100, 0, 200, on_eval);
+  o["Pawn Structure (Midgame)"] << Option(100, 0, 200, on_eval);
+  o["Pawn Structure (Endgame)"] << Option(100, 0, 200, on_eval);
+  o["Passed Pawns (Midgame)"]   << Option(100, 0, 200, on_eval);
+  o["Passed Pawns (Endgame)"]   << Option(100, 0, 200, on_eval);
+  o["Space"]                    << Option(100, 0, 200, on_eval);
+  o["Aggressiveness"]           << Option(100, 0, 200, on_eval);
+  o["Cowardice"]                << Option(100, 0, 200, on_eval);
+  o["Min Split Depth"]          << Option(0, 0, 12, on_threads);
+  o["Threads"]                  << Option(1, 1, MAX_THREADS, on_threads);
+  o["Hash"]                     << Option(32, 1, 16384, on_hash_size);
+  o["Clear Hash"]               << Option(on_clear_hash);
+  o["Ponder"]                   << Option(true);
+  o["OwnBook"]                  << Option(false);
+  o["MultiPV"]                  << Option(1, 1, 500);
+  o["Skill Level"]              << Option(20, 0, 20);
+  o["Emergency Move Horizon"]   << Option(40, 0, 50);
+  o["Emergency Base Time"]      << Option(60, 0, 30000);
+  o["Emergency Move Time"]      << Option(30, 0, 5000);
+  o["Minimum Thinking Time"]    << Option(20, 0, 5000);
+  o["Slow Mover"]               << Option(80, 10, 1000);
+  o["UCI_Chess960"]             << Option(false);
 }
 
 
@@ -96,7 +91,7 @@ void init(OptionsMap& o) {
 
 std::ostream& operator<<(std::ostream& os, const OptionsMap& om) {
 
-  for (size_t idx = 0; idx < om.size(); idx++)
+  for (size_t idx = 0; idx < om.size(); ++idx)
       for (OptionsMap::const_iterator it = om.begin(); it != om.end(); ++it)
           if (it->second.idx == idx)
           {
@@ -115,18 +110,18 @@ std::ostream& operator<<(std::ostream& os, const OptionsMap& om) {
 }
 
 
-/// Option c'tors and conversion operators
+/// Option class constructors and conversion operators
 
-Option::Option(const char* v, Fn* f) : type("string"), min(0), max(0), idx(Options.size()), on_change(f)
+Option::Option(const char* v, OnChange f) : type("string"), min(0), max(0), on_change(f)
 { defaultValue = currentValue = v; }
 
-Option::Option(bool v, Fn* f) : type("check"), min(0), max(0), idx(Options.size()), on_change(f)
+Option::Option(bool v, OnChange f) : type("check"), min(0), max(0), on_change(f)
 { defaultValue = currentValue = (v ? "true" : "false"); }
 
-Option::Option(Fn* f) : type("button"), min(0), max(0), idx(Options.size()), on_change(f)
+Option::Option(OnChange f) : type("button"), min(0), max(0), on_change(f)
 {}
 
-Option::Option(int v, int minv, int maxv, Fn* f) : type("spin"), min(minv), max(maxv), idx(Options.size()), on_change(f)
+Option::Option(int v, int minv, int maxv, OnChange f) : type("spin"), min(minv), max(maxv), on_change(f)
 { std::ostringstream ss; ss << v; defaultValue = currentValue = ss.str(); }
 
 
@@ -141,6 +136,17 @@ Option::operator std::string() const {
 }
 
 
+/// operator<<() inits options and assigns idx in the correct printing order
+
+void Option::operator<<(const Option& o) {
+
+  static size_t insert_order = 0;
+
+  *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.
@@ -158,7 +164,7 @@ Option& Option::operator=(const string& v) {
       currentValue = v;
 
   if (on_change)
-      (*on_change)(*this);
+      on_change(*this);
 
   return *this;
 }

src/ucioption.h

@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined(UCIOPTION_H_INCLUDED)
+#ifndef UCIOPTION_H_INCLUDED
 #define UCIOPTION_H_INCLUDED
 
 #include <map>
@@ -38,15 +38,16 @@ typedef std::map<std::string, Option, CaseInsensitiveLess> OptionsMap;
 /// Option class implements an option as defined by UCI protocol
 class Option {
 
-  typedef void (Fn)(const Option&);
+  typedef void (*OnChange)(const Option&);
 
 public:
-  Option(Fn* = NULL);
-  Option(bool v, Fn* = NULL);
-  Option(const char* v, Fn* = NULL);
-  Option(int v, int min, int max, Fn* = NULL);
+  Option(OnChange = NULL);
+  Option(bool v, OnChange = NULL);
+  Option(const char* v, OnChange = NULL);
+  Option(int v, int min, int max, OnChange = NULL);
 
   Option& operator=(const std::string& v);
+  void operator<<(const Option& o);
   operator int() const;
   operator std::string() const;
 
@@ -56,14 +57,14 @@ private:
   std::string defaultValue, currentValue, type;
   int min, max;
   size_t idx;
-  Fn* on_change;
+  OnChange on_change;
 };
 
 void init(OptionsMap&);
-void loop(const std::string&);
+void loop(int argc, char* argv[]);
 
 } // namespace UCI
 
 extern UCI::OptionsMap Options;
 
-#endif // !defined(UCIOPTION_H_INCLUDED)
+#endif // #ifndef UCIOPTION_H_INCLUDED