Small cleanups 12

- Clean signature of functions in namespace NNUE
- Add comment for countermove based pruning
- Remove bestMoveCount variable
- Add const qualifier to kpp_board_index array
- Fix spaces in get_best_thread()
- Fix indention in capture LMR code in search.cpp
- Rename TtmemDeleter to LargePageDeleter

Closes https://github.com/official-stockfish/Stockfish/pull/3063

No functional change

src/nnue/evaluate_nnue.cpp

@@ -30,7 +30,7 @@
 
 namespace Eval::NNUE {
 
-  uint32_t kpp_board_index[PIECE_NB][COLOR_NB] = {
+  const uint32_t kpp_board_index[PIECE_NB][COLOR_NB] = {
    // convention: W - us, B - them
    // viewed from other side, W and B are reversed
       { PS_NONE,     PS_NONE     },
@@ -136,10 +136,10 @@ namespace Eval::NNUE {
   }
 
   // Load eval, from a file stream or a memory stream
-  bool load_eval(std::string streamName, std::istream& stream) {
+  bool load_eval(std::string name, std::istream& stream) {
 
     Initialize();
-    fileName = streamName;
+    fileName = name;
     return ReadParameters(stream);
   }
 

src/nnue/evaluate_nnue.h

@@ -41,7 +41,7 @@ namespace Eval::NNUE {
   };
 
   template <typename T>
-  struct TtmemDeleter {
+  struct LargePageDeleter {
     void operator()(T* ptr) const {
       ptr->~T();
       aligned_large_pages_free(ptr);
@@ -52,7 +52,7 @@ namespace Eval::NNUE {
   using AlignedPtr = std::unique_ptr<T, AlignedDeleter<T>>;
 
   template <typename T>
-  using LargePagePtr = std::unique_ptr<T, TtmemDeleter<T>>;
+  using LargePagePtr = std::unique_ptr<T, LargePageDeleter<T>>;
 
 }  // namespace Eval::NNUE
 

src/nnue/nnue_common.h

@@ -113,7 +113,7 @@ namespace Eval::NNUE {
     PS_END2     = 12 * SQUARE_NB + 1
   };
 
-  extern uint32_t kpp_board_index[PIECE_NB][COLOR_NB];
+  extern const uint32_t kpp_board_index[PIECE_NB][COLOR_NB];
 
   // Type of input feature after conversion
   using TransformedFeatureType = std::uint8_t;