X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.h;h=e41044091566050567d413cb2d5888dba6585538;hp=4bd3e214d1ba98c9e3f8c6d80c190e0c8c24b5b1;hb=0ddf84870ad9f7fb4309e992e1e5eae968577958;hpb=ef6fca98a0b70b82ba701e6969a80cd9daf78705 diff --git a/src/pawns.h b/src/pawns.h index 4bd3e214..e4104409 100644 --- a/src/pawns.h +++ b/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) 2008-2009 Marco Costalba + Copyright (C) 2008-2010 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 @@ -26,71 +26,66 @@ //// #include "bitboard.h" +#include "position.h" +#include "tt.h" #include "value.h" + //// //// Types //// +const int PawnTableSize = 16384; + /// PawnInfo 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 get_pawn_info method in a PawnInfoTable object) /// returns a pointer to a PawnInfo object. -class Position; - class PawnInfo { friend class PawnInfoTable; public: - PawnInfo() { clear(); } - - Score value() const; - Value kingside_storm_value(Color c) const; - Value queenside_storm_value(Color c) const; + Score pawns_value() const; Bitboard pawn_attacks(Color c) const; - Bitboard passed_pawns() 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 get_king_shelter(const Position& pos, Color c, Square ksq); + + template + Score king_shelter(const Position& pos, Square ksq); private: - void clear(); - int updateShelter(const Position& pos, Color c, Square ksq); + template + Score updateShelter(const Position& pos, Square ksq); Key key; - Bitboard passedPawns; + Bitboard passedPawns[2]; Bitboard pawnAttacks[2]; - int16_t mgValue, egValue; - int16_t ksStormValue[2], qsStormValue[2]; - uint8_t halfOpenFiles[2]; Square kingSquares[2]; - uint8_t kingShelters[2]; + Score value; + int halfOpenFiles[2]; + Score kingShelters[2]; }; -/// The PawnInfoTable class represents a pawn hash table. It is basically -/// just an array of PawnInfo objects and a few methods for accessing these -/// objects. The most important method is get_pawn_info, which looks up a -/// position in the table and returns a pointer to a PawnInfo object. -class PawnInfoTable { +/// The PawnInfoTable class represents a pawn hash table. The most important +/// method is get_pawn_info, which returns a pointer to a PawnInfo object. + +class PawnInfoTable : public SimpleHash { + + enum SideType { KingSide, QueenSide }; public: - PawnInfoTable(unsigned numOfEntries); - ~PawnInfoTable(); - PawnInfo* get_pawn_info(const Position& pos); + PawnInfo* get_pawn_info(const Position& pos) const; + void prefetch(Key key) const; private: - typedef std::pair Values; - template - Values evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi); - - unsigned size; - PawnInfo* entries; + Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const; }; @@ -98,24 +93,23 @@ private: //// Inline functions //// -inline Score PawnInfo::value() const { - return make_score(mgValue, egValue); +inline void PawnInfoTable::prefetch(Key key) const { + + unsigned index = unsigned(key & (PawnTableSize - 1)); + PawnInfo* pi = entries + index; + ::prefetch((char*) pi); } -inline Bitboard PawnInfo::passed_pawns() const { - return passedPawns; +inline Score PawnInfo::pawns_value() const { + return value; } inline Bitboard PawnInfo::pawn_attacks(Color c) const { return pawnAttacks[c]; } -inline Value PawnInfo::kingside_storm_value(Color c) const { - return Value(ksStormValue[c]); -} - -inline Value PawnInfo::queenside_storm_value(Color c) const { - return Value(qsStormValue[c]); +inline Bitboard PawnInfo::passed_pawns(Color c) const { + return passedPawns[c]; } inline int PawnInfo::file_is_half_open(Color c, File f) const { @@ -130,8 +124,34 @@ inline int PawnInfo::has_open_file_to_right(Color c, File f) const { return halfOpenFiles[c] & ~((1 << int(f+1)) - 1); } -inline int PawnInfo::get_king_shelter(const Position& pos, Color c, Square ksq) { - return (kingSquares[c] == ksq ? kingShelters[c] : updateShelter(pos, c, ksq)); +/// PawnInfo::updateShelter() calculates and caches king shelter. It is called +/// only when king square changes, about 20% of total king_shelter() calls. +template +Score PawnInfo::updateShelter(const Position& pos, Square ksq) { + + const int Shift = (Us == WHITE ? 8 : -8); + + Bitboard pawns; + int r, shelter = 0; + + if (relative_rank(Us, ksq) <= RANK_4) + { + pawns = pos.pieces(PAWN, Us) & this_and_neighboring_files_bb(ksq); + r = square_rank(ksq) * 8; + for (int i = 1; i < 4; i++) + { + r += Shift; + shelter += BitCount8Bit[(pawns >> r) & 0xFF] * (128 >> i); + } + } + kingSquares[Us] = ksq; + kingShelters[Us] = make_score(shelter, 0); + return kingShelters[Us]; +} + +template +inline Score PawnInfo::king_shelter(const Position& pos, Square ksq) { + return kingSquares[Us] == ksq ? kingShelters[Us] : updateShelter(pos, ksq); } #endif // !defined(PAWNS_H_INCLUDED)