X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fpawns.h;h=d20e7c2ebe52786d715cf427a62aa31dbe34104b;hb=HEAD;hp=549aafa90b46c8290c80332af9e644edf0f6ee52;hpb=0fcda095df1caa860e8e3f3a714d5545ec9dc122;p=stockfish diff --git a/src/pawns.h b/src/pawns.h deleted file mode 100644 index 549aafa9..00000000 --- a/src/pawns.h +++ /dev/null @@ -1,146 +0,0 @@ -/* - Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - 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 - 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 . -*/ - -#if !defined(PAWNS_H_INCLUDED) -#define PAWNS_H_INCLUDED - -#include "bitboard.h" -#include "position.h" -#include "tt.h" -#include "types.h" - -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 PawnInfo { - - friend class PawnInfoTable; - -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; - - template - Score king_shelter(const Position& pos, Square ksq); - -private: - template - Score updateShelter(const Position& pos, Square ksq); - - Key key; - Bitboard passedPawns[2]; - Bitboard pawnAttacks[2]; - Square kingSquares[2]; - Score value; - int halfOpenFiles[2]; - Score kingShelters[2]; -}; - - -/// 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: - PawnInfo* get_pawn_info(const Position& pos) const; - void prefetch(Key key) const; - -private: - template - Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const; -}; - -inline Square pawn_push(Color c) { - return c == WHITE ? DELTA_N : DELTA_S; -} - -inline void PawnInfoTable::prefetch(Key key) const { - - unsigned index = unsigned(key & (PawnTableSize - 1)); - PawnInfo* pi = entries + index; - ::prefetch((char*) pi); -} - -inline Score PawnInfo::pawns_value() const { - return value; -} - -inline Bitboard PawnInfo::pawn_attacks(Color c) const { - return pawnAttacks[c]; -} - -inline Bitboard PawnInfo::passed_pawns(Color c) const { - return passedPawns[c]; -} - -inline int PawnInfo::file_is_half_open(Color c, File f) const { - return (halfOpenFiles[c] & (1 << int(f))); -} - -inline int PawnInfo::has_open_file_to_left(Color c, File f) const { - return halfOpenFiles[c] & ((1 << int(f)) - 1); -} - -inline int PawnInfo::has_open_file_to_right(Color c, File f) const { - return halfOpenFiles[c] & ~((1 << int(f+1)) - 1); -} - -/// 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)