X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=d92ed1caf4c4067f479407a31c6bc07ceba7206e;hp=4f18e67feeb37381c97534ec8abc0d7719167ebd;hb=eaed535c5f00ee75185e798dc2fe445a11e396af;hpb=1f97b48a31cd60d71c5fb63541cbf3991a094443 diff --git a/src/position.h b/src/position.h index 4f18e67f..d92ed1ca 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 Marco Costalba + Copyright (C) 2008-2009 Marco Costalba Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -21,12 +21,16 @@ #if !defined(POSITION_H_INCLUDED) #define POSITION_H_INCLUDED -// Disable a silly and noisy warning from MSVC compiler +// Disable some silly and noisy warning from MSVC compiler #if defined(_MSC_VER) // Forcing value to bool 'true' or 'false' (performance warning) #pragma warning(disable: 4800) +// Conditional expression is constant +#pragma warning(disable: 4127) + + #endif //// @@ -38,7 +42,6 @@ #include "direction.h" #include "move.h" #include "piece.h" -#include "phase.h" #include "square.h" #include "value.h" @@ -47,13 +50,12 @@ //// Constants //// -/// FEN string for the initial position: -const std::string StartPosition = - "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"; +/// FEN string for the initial position +const std::string StartPosition = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"; /// Maximum number of plies per game (220 should be enough, because the /// maximum search depth is 100, and during position setup we reset the -/// move counter for every non-reversible move): +/// move counter for every non-reversible move). const int MaxGameLength = 220; @@ -61,17 +63,35 @@ const int MaxGameLength = 220; //// Types //// -/// Castle rights, encoded as bit fields: +/// struct checkInfo is initialized at c'tor time and keeps +/// info used to detect if a move gives check. + +struct CheckInfo { + + CheckInfo(const Position&); + + Square ksq; + Bitboard dcCandidates; + Bitboard checkSq[8]; +}; + +/// Castle rights, encoded as bit fields enum CastleRights { - NO_CASTLES = 0, - WHITE_OO = 1, - BLACK_OO = 2, - WHITE_OOO = 4, - BLACK_OOO = 8, + NO_CASTLES = 0, + WHITE_OO = 1, + BLACK_OO = 2, + WHITE_OOO = 4, + BLACK_OOO = 8, ALL_CASTLES = 15 }; +/// Game phase +enum Phase { + PHASE_ENDGAME = 0, + PHASE_MIDGAME = 128 +}; + /// The StateInfo struct stores information we need to restore a Position /// object to its previous state when we retract a move. Whenever a move @@ -79,37 +99,38 @@ enum CastleRights { /// must be passed as a parameter. struct StateInfo { - Bitboard pinners[2], pinned[2], dcCandidates[2], checkersBB; - Key key, pawnKey, materialKey; - int castleRights, rule50; + Key pawnKey, materialKey; + int castleRights, rule50, pliesFromNull; Square epSquare; - Value mgValue, egValue; + Score value; + Value npMaterial[2]; + + Key key; PieceType capture; + Bitboard checkersBB; StateInfo* previous; - Move lastMove; }; -/// The position data structure. A position consists of the following data: +/// 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 occupiecd by +/// * 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 +/// * 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. -/// * The last move played. /// * 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 +/// * Hash keys for all previous positions in the game for detecting /// repetition draws. /// * A counter for detecting 50 move rule draws. @@ -119,10 +140,15 @@ class Position { friend class EndgameFunctions; public: + enum GamePhase { + MidGame, + EndGame + }; + // Constructors - Position() {}; - Position(const Position& pos); - Position(const std::string& fen); + Position(); + explicit Position(const Position& pos); + explicit Position(const std::string& fen); // Text input/output void from_fen(const std::string& fen); @@ -130,8 +156,8 @@ public: void print(Move m = MOVE_NONE) const; // Copying - void copy(const Position &pos); - void flipped_copy(const Position &pos); + void fast_copy(const Position& pos); + void flipped_copy(const Position& pos); // The piece on a given square Piece piece_on(Square s) const; @@ -149,26 +175,10 @@ public: Bitboard empty_squares() const; Bitboard occupied_squares() const; Bitboard pieces_of_color(Color c) const; - Bitboard pieces_of_type(PieceType pt) const; - Bitboard pieces_of_color_and_type(Color c, PieceType pt) const; - Bitboard pawns() const; - Bitboard knights() const; - Bitboard bishops() const; - Bitboard rooks() const; - Bitboard queens() const; - Bitboard kings() const; - Bitboard rooks_and_queens() const; - Bitboard bishops_and_queens() const; - Bitboard sliders() const; - Bitboard pawns(Color c) const; - Bitboard knights(Color c) const; - Bitboard bishops(Color c) const; - Bitboard rooks(Color c) const; - Bitboard queens(Color c) const; - Bitboard kings(Color c) const; - Bitboard rooks_and_queens(Color c) const; - Bitboard bishops_and_queens(Color c) const; - Bitboard sliders_of_color(Color c) 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; @@ -186,62 +196,50 @@ public: Square initial_kr_square(Color c) const; Square initial_qr_square(Color c) const; - // Attack bitboards - Bitboard sliding_attacks(Square s, Direction d) const; - Bitboard ray_attacks(Square s, SignedDirection d) const; - Bitboard pawn_attacks(Color c, Square s) const; - - template - Bitboard piece_attacks(Square s) const; - // Bitboards for pinned pieces and discovered check candidates Bitboard discovered_check_candidates(Color c) const; - Bitboard pinned_pieces(Color c, Bitboard& p) const; Bitboard pinned_pieces(Color c) const; - // Checking pieces + // Checking pieces and under check information Bitboard checkers() const; + bool is_check() const; // Piece lists Square piece_list(Color c, PieceType pt, int index) const; + const Square* piece_list_begin(Color c, PieceType pt) const; - // Attack information for a given square - bool square_is_attacked(Square s, Color c) const; - Bitboard attacks_to(Square s) const; - Bitboard attacks_to(Square s, Color c) const; - bool is_check() const; - bool pawn_attacks_square(Color c, Square f, Square t) const; - - template - Bitboard piece_attacks_square(Square f, Square t) const; // Dispatch at compile-time - - bool piece_attacks_square(Piece p, Square f, Square t) const; // Dispatch at run-time + // Information about attacks to or from a given square + Bitboard attackers_to(Square s) const; + Bitboard attacks_from(Piece p, Square s) const; + template Bitboard attacks_from(Square s) const; + template Bitboard attacks_from(Square s, Color c) const; // Properties of moves - bool pl_move_is_legal(Move m) const; + bool pl_move_is_legal(Move m, Bitboard pinned) const; + bool pl_move_is_evasion(Move m, Bitboard pinned) const; bool move_is_check(Move m) const; + bool move_is_check(Move m, const CheckInfo& ci) const; bool move_is_capture(Move m) const; - bool move_is_deep_pawn_push(Move m) const; - bool move_is_pawn_push_to_7th(Move m) const; + bool move_is_capture_or_promotion(Move m) const; bool move_is_passed_pawn_push(Move m) const; - bool move_was_passed_pawn_push(Move m) const; bool move_attacks_square(Move m, Square s) const; + // Piece captured with previous moves + PieceType captured_piece() const; + // Information about pawns bool pawn_is_passed(Color c, Square s) const; - bool pawn_is_isolated(Color c, Square s) const; - bool pawn_is_doubled(Color c, Square s) const; - - // Open and half-open files - bool file_is_open(File f) const; - bool file_is_half_open(Color c, File f) const; + static bool pawn_is_passed(Bitboard theirPawns, Color c, Square s); + static bool pawn_is_isolated(Bitboard ourPawns, Square s); + static bool pawn_is_doubled(Bitboard ourPawns, Color c, Square s); // Weak squares bool square_is_weak(Square s, Color c) const; // Doing and undoing moves - void setStartState(const StateInfo& st); + void detach(); void do_move(Move m, StateInfo& st); + void do_move(Move m, StateInfo& st, const CheckInfo& ci, bool moveIsCheck); void undo_move(Move m); void do_null_move(StateInfo& st); void undo_null_move(); @@ -250,18 +248,18 @@ public: int see(Square from, Square to) const; int see(Move m) const; int see(Square to) const; + int see_sign(Move m) const; // Accessing hash keys Key get_key() const; + Key get_exclusion_key() const; Key get_pawn_key() const; Key get_material_key() const; // Incremental evaluation - Value mg_value() const; - Value eg_value() const; + Score value() const; Value non_pawn_material(Color c) const; - Phase game_phase() const; - Value mg_pst_delta(Move m) const; + Score pst_delta(Piece piece, Square from, Square to) const; // Game termination checks bool is_mate() const; @@ -283,17 +281,12 @@ public: // Position consistency check, for debugging bool is_ok(int* failedStep = NULL) const; - // Static member functions: + // Static member functions static void init_zobrist(); static void init_piece_square_tables(); private: - enum { - Pinned = 1, - DcCandidates = 2 - }; - // Initialization helper functions (used while setting up a position) void clear(); void put_piece(Piece p, Square s); @@ -301,23 +294,13 @@ private: void allow_ooo(Color c); // Helper functions for doing and undoing moves - void do_capture_move(Move m, PieceType capture, Color them, Square to); + void do_capture_move(Bitboard& key, PieceType capture, Color them, Square to, bool ep); void do_castle_move(Move m); - void do_promotion_move(Move m); - void do_ep_move(Move m); void undo_castle_move(Move m); - void undo_promotion_move(Move m); - void undo_ep_move(Move m); void find_checkers(); - void find_hidden_checks(Color us, unsigned int types); - void find_hidden_checks(); - void update_hidden_checks(Square from, Square to); - template - void update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, Square to, Bitboard dcCandidates); - - template - Bitboard hidden_checks(Color c, Square ksq, Bitboard& pinners) const; + template + Bitboard hidden_checkers(Color c) const; // Computing hash keys from scratch (for initialization and debugging) Key compute_key() const; @@ -325,33 +308,27 @@ private: Key compute_material_key() const; // Computing incremental evaluation scores and material counts - enum GamePhase { - MidGame, - EndGame - }; - template Value pst(Color c, PieceType pt, Square s) const; - template Value compute_value() const; + Score pst(Color c, PieceType pt, Square s) const; + Score compute_value() const; Value compute_non_pawn_material(Color c) const; - // Bitboards - Bitboard byColorBB[2], byTypeBB[8]; - // Board Piece board[64]; + // Bitboards + Bitboard byTypeBB[8], byColorBB[2]; + // Piece counts int pieceCount[2][8]; // [color][pieceType] // Piece lists Square pieceList[2][8][16]; // [color][pieceType][index] - int index[64]; + int index[64]; // [square] // Other info - Square kingSquare[2]; Color sideToMove; int gamePly; Key history[MaxGameLength]; - Value npMaterial[2]; File initialKFile, initialKRFile, initialQRFile; StateInfo startState; StateInfo* st; @@ -363,8 +340,8 @@ private: static Key zobCastle[16]; static Key zobMaterial[2][8][16]; static Key zobSideToMove; - static Value MgPieceSquareTable[16][64]; - static Value EgPieceSquareTable[16][64]; + static Score PieceSquareTable[16][64]; + static Key zobExclusion; }; @@ -416,84 +393,20 @@ inline Bitboard Position::pieces_of_color(Color c) const { return byColorBB[c]; } -inline Bitboard Position::pieces_of_type(PieceType pt) const { +inline Bitboard Position::pieces(PieceType pt) const { return byTypeBB[pt]; } -inline Bitboard Position::pieces_of_color_and_type(Color c, PieceType pt) const { - return pieces_of_color(c) & pieces_of_type(pt); -} - -inline Bitboard Position::pawns() const { - return pieces_of_type(PAWN); -} - -inline Bitboard Position::knights() const { - return pieces_of_type(KNIGHT); -} - -inline Bitboard Position::bishops() const { - return pieces_of_type(BISHOP); -} - -inline Bitboard Position::rooks() const { - return pieces_of_type(ROOK); -} - -inline Bitboard Position::queens() const { - return pieces_of_type(QUEEN); -} - -inline Bitboard Position::kings() const { - return pieces_of_type(KING); -} - -inline Bitboard Position::rooks_and_queens() const { - return rooks() | queens(); -} - -inline Bitboard Position::bishops_and_queens() const { - return bishops() | queens(); -} - -inline Bitboard Position::sliders() const { - return bishops() | queens() | rooks(); -} - -inline Bitboard Position::pawns(Color c) const { - return pieces_of_color_and_type(c, PAWN); -} - -inline Bitboard Position::knights(Color c) const { - return pieces_of_color_and_type(c, KNIGHT); -} - -inline Bitboard Position::bishops(Color c) const { - return pieces_of_color_and_type(c, BISHOP); -} - -inline Bitboard Position::rooks(Color c) const { - return pieces_of_color_and_type(c, ROOK); -} - -inline Bitboard Position::queens(Color c) const { - return pieces_of_color_and_type(c, QUEEN); +inline Bitboard Position::pieces(PieceType pt, Color c) const { + return byTypeBB[pt] & byColorBB[c]; } -inline Bitboard Position::kings(Color c) const { - return pieces_of_color_and_type(c, KING); +inline Bitboard Position::pieces(PieceType pt1, PieceType pt2) const { + return byTypeBB[pt1] | byTypeBB[pt2]; } -inline Bitboard Position::rooks_and_queens(Color c) const { - return rooks_and_queens() & pieces_of_color(c); -} - -inline Bitboard Position::bishops_and_queens(Color c) const { - return bishops_and_queens() & pieces_of_color(c); -} - -inline Bitboard Position::sliders_of_color(Color c) const { - return sliders() & pieces_of_color(c); +inline Bitboard Position::pieces(PieceType pt1, PieceType pt2, Color c) const { + return (byTypeBB[pt1] | byTypeBB[pt2]) & byColorBB[c]; } inline int Position::piece_count(Color c, PieceType pt) const { @@ -504,12 +417,16 @@ inline Square Position::piece_list(Color c, PieceType pt, int index) const { return pieceList[c][pt][index]; } +inline const Square* Position::piece_list_begin(Color c, PieceType pt) const { + return pieceList[c][pt]; +} + inline Square Position::ep_square() const { return st->epSquare; } inline Square Position::king_square(Color c) const { - return kingSquare[c]; + return pieceList[c][KING][0]; } inline bool Position::can_castle_kingside(Color side) const { @@ -532,51 +449,29 @@ inline Square Position::initial_qr_square(Color c) const { return relative_square(c, make_square(initialQRFile, RANK_1)); } -inline Bitboard Position::pawn_attacks(Color c, Square s) const { - return StepAttackBB[piece_of_color_and_type(c, PAWN)][s]; -} - template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[piece_of_color_and_type(opposite_color(sideToMove), PAWN)][s]; +inline Bitboard Position::attacks_from(Square s, Color c) const { + return StepAttackBB[piece_of_color_and_type(c, PAWN)][s]; } -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[KNIGHT][s]; +template // Knight and King and white pawns +inline Bitboard Position::attacks_from(Square s) const { + return StepAttackBB[Piece][s]; } template<> -inline Bitboard Position::piece_attacks(Square s) const { +inline Bitboard Position::attacks_from(Square s) const { return bishop_attacks_bb(s, occupied_squares()); } template<> -inline Bitboard Position::piece_attacks(Square s) const { +inline Bitboard Position::attacks_from(Square s) const { return rook_attacks_bb(s, occupied_squares()); } template<> -inline Bitboard Position::piece_attacks(Square s) const { - return piece_attacks(s) | piece_attacks(s); -} - -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[KING][s]; -} - -inline Bitboard Position::pinned_pieces(Color c) const { - return st->pinned[c]; -} - -inline Bitboard Position::pinned_pieces(Color c, Bitboard& p) const { - p = st->pinners[c]; - return st->pinned[c]; -} - -inline Bitboard Position::discovered_check_candidates(Color c) const { - return st->dcCandidates[c]; +inline Bitboard Position::attacks_from(Square s) const { + return attacks_from(s) | attacks_from(s); } inline Bitboard Position::checkers() const { @@ -587,53 +482,34 @@ inline bool Position::is_check() const { return st->checkersBB != EmptyBoardBB; } -inline bool Position::pawn_attacks_square(Color c, Square f, Square t) const { - return bit_is_set(pawn_attacks(c, f), t); -} - -template -Bitboard Position::piece_attacks_square(Square f, Square t) const { - return bit_is_set(piece_attacks(f), t); -} - -inline Bitboard Position::attacks_to(Square s, Color c) const { - - return attacks_to(s) & pieces_of_color(c); -} - -inline bool Position::square_is_attacked(Square s, Color c) const { - - return attacks_to(s, c) != EmptyBoardBB; -} - inline bool Position::pawn_is_passed(Color c, Square s) const { - return !(pawns(opposite_color(c)) & passed_pawn_mask(c, s)); -} - -inline bool Position::pawn_is_isolated(Color c, Square s) const { - return !(pawns(c) & neighboring_files_bb(s)); + return !(pieces(PAWN, opposite_color(c)) & passed_pawn_mask(c, s)); } -inline bool Position::pawn_is_doubled(Color c, Square s) const { - return pawns(c) & squares_behind(c, s); +inline bool Position::pawn_is_passed(Bitboard theirPawns, Color c, Square s) { + return !(theirPawns & passed_pawn_mask(c, s)); } -inline bool Position::file_is_open(File f) const { - return !(pawns() & file_bb(f)); +inline bool Position::pawn_is_isolated(Bitboard ourPawns, Square s) { + return !(ourPawns & neighboring_files_bb(s)); } -inline bool Position::file_is_half_open(Color c, File f) const { - return !(pawns(c) & file_bb(f)); +inline bool Position::pawn_is_doubled(Bitboard ourPawns, Color c, Square s) { + return ourPawns & squares_behind(c, s); } inline bool Position::square_is_weak(Square s, Color c) const { - return !(pawns(c) & outpost_mask(opposite_color(c), s)); + return !(pieces(PAWN, c) & outpost_mask(opposite_color(c), s)); } inline Key Position::get_key() const { return st->key; } +inline Key Position::get_exclusion_key() const { + return st->key ^ zobExclusion; +} + inline Key Position::get_pawn_key() const { return st->pawnKey; } @@ -642,63 +518,20 @@ inline Key Position::get_material_key() const { return st->materialKey; } -template -inline Value Position::pst(Color c, PieceType pt, Square s) const { - return (Phase == MidGame ? MgPieceSquareTable[piece_of_color_and_type(c, pt)][s] - : EgPieceSquareTable[piece_of_color_and_type(c, pt)][s]); -} - -inline Value Position::mg_pst_delta(Move m) const { - return MgPieceSquareTable[piece_on(move_from(m))][move_to(m)] - -MgPieceSquareTable[piece_on(move_from(m))][move_from(m)]; +inline Score Position::pst(Color c, PieceType pt, Square s) const { + return PieceSquareTable[piece_of_color_and_type(c, pt)][s]; } -inline Value Position::mg_value() const { - return st->mgValue; +inline Score Position::pst_delta(Piece piece, Square from, Square to) const { + return PieceSquareTable[piece][to] - PieceSquareTable[piece][from]; } -inline Value Position::eg_value() const { - return st->egValue; +inline Score Position::value() const { + return st->value; } inline Value Position::non_pawn_material(Color c) const { - return npMaterial[c]; -} - -inline Phase Position::game_phase() const { - - // The purpose of the Value(325) terms below is to make sure the difference - // between MidgameLimit and EndgameLimit is a power of 2, which should make - // the division at the end of the function a bit faster. - static const Value MidgameLimit = 2 * QueenValueMidgame - + 2 * RookValueMidgame - + 6 * BishopValueMidgame - + Value(325); - - static const Value EndgameLimit = 4 * RookValueMidgame - Value(325); - - Value npm = non_pawn_material(WHITE) + non_pawn_material(BLACK); - - if (npm >= MidgameLimit) - return PHASE_MIDGAME; - else if(npm <= EndgameLimit) - return PHASE_ENDGAME; - else - return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit)); -} - -inline bool Position::move_is_deep_pawn_push(Move m) const { - - Color c = side_to_move(); - return piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN) - && relative_rank(c, move_to(m)) > RANK_4; -} - -inline bool Position::move_is_pawn_push_to_7th(Move m) const { - - Color c = side_to_move(); - return piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN) - && relative_rank(c, move_to(m)) == RANK_7; + return st->npMaterial[c]; } inline bool Position::move_is_passed_pawn_push(Move m) const { @@ -708,13 +541,6 @@ inline bool Position::move_is_passed_pawn_push(Move m) const { && pawn_is_passed(c, move_to(m)); } -inline bool Position::move_was_passed_pawn_push(Move m) const { - - Color c = opposite_color(side_to_move()); - return piece_on(move_to(m)) == piece_of_color_and_type(c, PAWN) - && pawn_is_passed(c, move_to(m)); -} - inline int Position::rule_50_counter() const { return st->rule50; @@ -729,8 +555,23 @@ inline bool Position::opposite_colored_bishops() const { inline bool Position::has_pawn_on_7th(Color c) const { - return pawns(c) & relative_rank_bb(c, RANK_7); + return pieces(PAWN, c) & relative_rank_bb(c, RANK_7); } +inline bool Position::move_is_capture(Move m) const { + + // Move must not be MOVE_NONE ! + return (m & (3 << 15)) ? !move_is_castle(m) : !square_is_empty(move_to(m)); +} + +inline bool Position::move_is_capture_or_promotion(Move m) const { + + // Move must not be MOVE_NONE ! + return (m & (0x1F << 12)) ? !move_is_castle(m) : !square_is_empty(move_to(m)); +} + +inline PieceType Position::captured_piece() const { + return st->capture; +} #endif // !defined(POSITION_H_INCLUDED)