X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=8b81358769854354b0fc07ad828711ebf0518378;hp=30c25652f5b2455f966cd6767d9ae5011c43b814;hb=7e95495b35ef84a87fa6be34639a5f96e67972b0;hpb=34178205fc762638e633a61ecc45360e1662bdee diff --git a/src/position.h b/src/position.h index 30c25652..8b813587 100644 --- a/src/position.h +++ b/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) 2008-2013 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 @@ -21,6 +21,7 @@ #define POSITION_H_INCLUDED #include +#include #include "bitboard.h" #include "types.h" @@ -29,6 +30,7 @@ /// The checkInfo struct is initialized at c'tor time and keeps info used /// to detect if a move gives check. class Position; +struct Thread; struct CheckInfo { @@ -36,21 +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 /// 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 +/// 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]; + Value npMaterial[COLOR_NB]; int castleRights, rule50, pliesFromNull; - Score value; + Score psqScore; Square epSquare; Key key; @@ -60,6 +62,11 @@ struct StateInfo { }; +/// 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 @@ -83,65 +90,43 @@ struct StateInfo { /// * A counter for detecting 50 move rule draws. class Position { - - // No copy c'tor or assignment operator allowed - Position(const Position&); - Position& operator=(const Position&); - public: Position() {} - Position(const Position& pos, int th) { copy(pos, th); } - Position(const std::string& fen, bool isChess960, int th); + Position(const Position& p, Thread* t) { *this = p; thisThread = t; } + Position(const std::string& f, bool c960, Thread* t) { set(f, c960, t); } + Position& operator=(const Position&); // Text input/output - void copy(const Position& pos, int th); - void from_fen(const std::string& fen, bool isChess960); - const std::string to_fen() const; - void print(Move m = MOVE_NONE) const; - - // The piece on a given square - Piece piece_on(Square s) const; - Piece piece_moved(Move m) const; - bool square_is_empty(Square s) const; - - // Side to move - Color side_to_move() const; + void set(const std::string& fen, bool isChess960, Thread* th); + const std::string fen() const; + const std::string pretty(Move m = MOVE_NONE) const; - // Bitboard representation of the position - Bitboard occupied_squares() const; - Bitboard pieces(Color c) const; + // Position representation + Bitboard pieces() const; Bitboard pieces(PieceType pt) const; - Bitboard pieces(PieceType pt, Color c) const; Bitboard pieces(PieceType pt1, PieceType pt2) const; - Bitboard pieces(PieceType pt1, PieceType pt2, Color c) const; - - // Number of pieces of each color and type - int piece_count(Color c, PieceType pt) const; - - // The en passant square - Square ep_square() const; - - // Current king position for each color + Bitboard pieces(Color c) const; + Bitboard pieces(Color c, PieceType pt) const; + Bitboard pieces(Color c, PieceType pt1, PieceType pt2) const; + 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; - // Castling rights - bool can_castle(CastleRight f) const; - bool can_castle(Color c) const; - bool castle_impeded(CastleRight f) const; - Square castle_rook_square(CastleRight f) 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; - // Bitboards for pinned pieces and discovered check candidates + // Checking + Bitboard checkers() const; Bitboard discovered_check_candidates() const; Bitboard pinned_pieces() const; - // Checking pieces and under check information - Bitboard checkers() const; - bool in_check() const; - - // Piece lists - const Square* piece_list(Color c, PieceType pt) const; - - // Information about attacks to or from a given square + // 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; @@ -151,27 +136,29 @@ public: // Properties of moves bool move_gives_check(Move m, const CheckInfo& ci) const; - bool move_attacks_square(Move m, Square s) 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 captured with previous moves + Piece piece_moved(Move m) const; PieceType captured_piece_type() const; - // Information about pawns + // Piece specific bool pawn_is_passed(Color c, Square s) const; + bool pawn_on_7th(Color c) const; + bool opposite_bishops() const; + bool bishop_pair(Color c) 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 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(Move m, int asymmThreshold = 0) const; int see_sign(Move m) const; // Accessing hash keys @@ -180,39 +167,31 @@ public: Key pawn_key() const; Key material_key() const; - // Incremental evaluation - Score value() const; + // Incremental piece-square evaluation + Score psq_score() const; Value non_pawn_material(Color c) const; - Score pst_delta(Piece piece, Square from, Square to) const; // Other properties of the position - template bool is_draw() const; - int startpos_ply_counter() const; - bool opposite_colored_bishops() const; - bool both_color_bishops(Color c) const; - bool has_pawn_on_7th(Color c) const; + Color side_to_move() const; + int game_ply() const; bool is_chess960() const; - int thread() const; + Thread* this_thread() const; int64_t nodes_searched() const; void set_nodes_searched(int64_t n); + bool is_draw() const; // Position consistency check, for debugging bool pos_is_ok(int* failedStep = NULL) const; - void flip_me(); - - // Global initialization - static void init(); + void flip(); private: - - // Initialization helper functions (used while setting up a position) + // 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); - bool move_is_legal(const Move m) const; - // Helper template functions - template void do_castle_move(Move m); + // Helper functions + void do_castle(Square kfrom, Square kto, Square rfrom, Square rto); template Bitboard hidden_checkers() const; // Computing hash keys from scratch (for initialization and debugging) @@ -221,44 +200,28 @@ private: Key compute_material_key() const; // Computing incremental evaluation scores and material counts - Score pst(Piece p, Square s) const; - Score compute_value() const; + Score compute_psq_score() const; Value compute_non_pawn_material(Color c) const; - // Board - Piece board[64]; // [square] - - // Bitboards - Bitboard byTypeBB[8]; // [pieceType] - Bitboard byColorBB[2]; // [color] - Bitboard occupied; - - // Piece counts - int pieceCount[2][8]; // [color][pieceType] - - // Piece lists - Square pieceList[2][8][16]; // [color][pieceType][index] - int index[64]; // [square] + // Board and pieces + 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[16]; // [castleRight] - Bitboard castlePath[16]; // [castleRight] + int castleRightsMask[SQUARE_NB]; + Square castleRookSquare[COLOR_NB][CASTLING_SIDE_NB]; + Bitboard castlePath[COLOR_NB][CASTLING_SIDE_NB]; StateInfo startState; int64_t nodes; - int startPosPly; + int gamePly; Color sideToMove; - int threadID; + Thread* thisThread; StateInfo* st; int chess960; - - // Static variables - static Score pieceSquareTable[16][64]; // [piece][square] - static Key zobrist[2][8][64]; // [color][pieceType][square]/[piece count] - static Key zobEp[8]; // [file] - static Key zobCastle[16]; // [castleRight] - static Key zobSideToMove; - static Key zobExclusion; }; inline int64_t Position::nodes_searched() const { @@ -277,7 +240,7 @@ inline Piece Position::piece_moved(Move m) const { return board[from_sq(m)]; } -inline bool Position::square_is_empty(Square s) const { +inline bool Position::is_empty(Square s) const { return board[s] == NO_PIECE; } @@ -285,28 +248,28 @@ inline Color Position::side_to_move() const { return sideToMove; } -inline Bitboard Position::occupied_squares() const { - return occupied; -} - -inline Bitboard Position::pieces(Color c) const { - return byColorBB[c]; +inline Bitboard Position::pieces() const { + return byTypeBB[ALL_PIECES]; } inline Bitboard Position::pieces(PieceType pt) const { return byTypeBB[pt]; } -inline Bitboard Position::pieces(PieceType pt, Color c) const { - return byTypeBB[pt] & byColorBB[c]; -} - inline Bitboard Position::pieces(PieceType pt1, PieceType pt2) const { return byTypeBB[pt1] | byTypeBB[pt2]; } -inline Bitboard Position::pieces(PieceType pt1, PieceType pt2, Color c) const { - return (byTypeBB[pt1] | byTypeBB[pt2]) & byColorBB[c]; +inline Bitboard Position::pieces(Color c) const { + return byColorBB[c]; +} + +inline Bitboard Position::pieces(Color c, PieceType pt) const { + return byColorBB[c] & byTypeBB[pt]; +} + +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 { @@ -325,25 +288,26 @@ inline Square Position::king_square(Color c) const { return pieceList[c][KING][0]; } -inline bool Position::can_castle(CastleRight f) const { +inline int Position::can_castle(CastleRight f) const { return st->castleRights & f; } -inline bool Position::can_castle(Color c) const { - return st->castleRights & ((WHITE_OO | WHITE_OOO) << c); +inline int Position::can_castle(Color c) const { + return st->castleRights & ((WHITE_OO | WHITE_OOO) << (2 * c)); } -inline bool Position::castle_impeded(CastleRight f) const { - return occupied & castlePath[f]; +inline bool Position::castle_impeded(Color c, CastlingSide s) const { + return byTypeBB[ALL_PIECES] & castlePath[c][s]; } -inline Square Position::castle_rook_square(CastleRight f) const { - return castleRookSquare[f]; +inline Square Position::castle_rook_square(Color c, CastlingSide s) const { + return castleRookSquare[c][s]; } template inline Bitboard Position::attacks_from(Square s) const { - return Pt == BISHOP || Pt == ROOK ? attacks_bb(s, occupied_squares()) + + return Pt == BISHOP || Pt == ROOK ? attacks_bb(s, pieces()) : Pt == QUEEN ? attacks_from(s) | attacks_from(s) : StepAttacksBB[Pt][s]; } @@ -354,21 +318,17 @@ inline Bitboard Position::attacks_from(Square s, Color c) const { } inline Bitboard Position::attacks_from(Piece p, Square s) const { - return attacks_from(p, s, occupied); + return attacks_from(p, s, byTypeBB[ALL_PIECES]); } inline Bitboard Position::attackers_to(Square s) const { - return attackers_to(s, occupied); + return attackers_to(s, byTypeBB[ALL_PIECES]); } 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(); } @@ -378,7 +338,7 @@ inline Bitboard Position::pinned_pieces() const { } inline bool Position::pawn_is_passed(Color c, Square s) const { - return !(pieces(PAWN, ~c) & passed_pawn_mask(c, s)); + return !(pieces(~c, PAWN) & passed_pawn_mask(c, s)); } inline Key Position::key() const { @@ -386,7 +346,7 @@ inline Key Position::key() const { } inline Key Position::exclusion_key() const { - return st->key ^ zobExclusion; + return st->key ^ Zobrist::exclusion; } inline Key Position::pawn_key() const { @@ -397,16 +357,8 @@ inline Key Position::material_key() const { return st->materialKey; } -inline Score Position::pst(Piece p, Square s) const { - return pieceSquareTable[p][s]; -} - -inline Score Position::pst_delta(Piece piece, Square from, Square to) const { - return pieceSquareTable[piece][to] - pieceSquareTable[piece][from]; -} - -inline Score Position::value() const { - return st->value; +inline Score Position::psq_score() const { + return st->psqScore; } inline Value Position::non_pawn_material(Color c) const { @@ -415,29 +367,29 @@ inline Value Position::non_pawn_material(Color c) const { inline bool Position::is_passed_pawn_push(Move m) const { - return board[from_sq(m)] == make_piece(sideToMove, PAWN) + 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_colored_bishops() const { +inline bool Position::opposite_bishops() const { return pieceCount[WHITE][BISHOP] == 1 && pieceCount[BLACK][BISHOP] == 1 && opposite_colors(pieceList[WHITE][BISHOP][0], pieceList[BLACK][BISHOP][0]); } -inline bool Position::both_color_bishops(Color c) const { - // Assumes that there are only two bishops - return pieceCount[c][BISHOP] >= 2 && - opposite_colors(pieceList[c][BISHOP][0], pieceList[c][BISHOP][1]); +inline bool Position::bishop_pair(Color c) const { + + return pieceCount[c][BISHOP] >= 2 + && opposite_colors(pieceList[c][BISHOP][0], pieceList[c][BISHOP][1]); } -inline bool Position::has_pawn_on_7th(Color c) const { - return pieces(PAWN, c) & rank_bb(relative_rank(c, RANK_7)); +inline bool Position::pawn_on_7th(Color c) const { + return pieces(c, PAWN) & rank_bb(relative_rank(c, RANK_7)); } inline bool Position::is_chess960() const { @@ -447,22 +399,22 @@ inline bool Position::is_chess960() const { inline bool Position::is_capture_or_promotion(Move m) const { assert(is_ok(m)); - return is_special(m) ? !is_castle(m) : !square_is_empty(to_sq(m)); + return type_of(m) ? type_of(m) != CASTLE : !is_empty(to_sq(m)); } inline bool Position::is_capture(Move m) const { // Note that castle is coded as "king captures the rook" assert(is_ok(m)); - return (!square_is_empty(to_sq(m)) && !is_castle(m)) || is_enpassant(m); + return (!is_empty(to_sq(m)) && type_of(m) != CASTLE) || type_of(m) == ENPASSANT; } inline PieceType Position::captured_piece_type() const { return st->capturedType; } -inline int Position::thread() const { - return threadID; +inline Thread* Position::this_thread() const { + return thisThread; } #endif // !defined(POSITION_H_INCLUDED)