X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=3947180f6f6528a404e6fc48d6b0d4af150ff128;hp=6667de704f3e15508f45b1b1239f46d88d536a9f;hb=3184852bdce27e387852f4e250c3c5b502706cb3;hpb=7caa6cd3383cf90189a1947c9bdf9c6fea1172a6 diff --git a/src/position.h b/src/position.h index 6667de70..3947180f 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) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 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 @@ -21,17 +21,18 @@ #define POSITION_H_INCLUDED #include -#include +#include // For offsetof() +#include #include "bitboard.h" -#include "bitcount.h" #include "types.h" -/// The checkInfo struct is initialized at c'tor time and keeps info used -/// to detect if a move gives check. class Position; struct Thread; +/// CheckInfo struct is initialized at c'tor time and keeps info used to detect +/// if a move gives check. + struct CheckInfo { explicit CheckInfo(const Position&); @@ -39,50 +40,52 @@ struct CheckInfo { Bitboard dcCandidates; Bitboard pinned; Bitboard checkSq[PIECE_TYPE_NB]; - Square ksq; + Square ksq; }; -/// The StateInfo struct stores information needed 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), a StateInfo -/// object must be passed as a parameter. +/// StateInfo struct stores information needed 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), a StateInfo object must be passed. struct StateInfo { - Key pawnKey, materialKey; - Value npMaterial[COLOR_NB]; - int castlingRights, rule50, pliesFromNull; - Score psq; + + // Copied when making a move + Key pawnKey; + Key materialKey; + Value nonPawnMaterial[COLOR_NB]; + int castlingRights; + int rule50; + int pliesFromNull; + Score psq; Square epSquare; - Key key; - Bitboard checkersBB; - PieceType capturedType; + // Not copied when making a move + Key key; + Bitboard checkersBB; + PieceType capturedType; StateInfo* previous; }; -/// 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 class stores the information regarding the board representation -/// like pieces, side to move, hash keys, castling info, etc. The most important -/// methods are do_move() and undo_move(), used by the search to update node info -/// when traversing the search tree. +/// Position class stores information regarding the board representation as +/// pieces, side to move, hash keys, castling info, etc. Important methods are +/// do_move() and undo_move(), used by the search to update node info when +/// traversing the search tree. class Position { friend std::ostream& operator<<(std::ostream&, const Position&); public: - Position() {} - Position(const Position& pos, Thread* t) { *this = pos; thisThread = t; } - Position(const std::string& f, bool c960, Thread* t) { set(f, c960, t); } - Position& operator=(const Position&); static void init(); + Position() = default; // To define the global object RootPos + Position(const Position&) = delete; + Position(const Position& pos, Thread* th) { *this = pos; thisThread = th; } + Position(const std::string& f, bool c960, Thread* th) { set(f, c960, th); } + Position& operator=(const Position&); // To assign RootPos from UCI + // FEN string input/output void set(const std::string& fenStr, bool isChess960, Thread* th); const std::string fen() const; @@ -100,7 +103,6 @@ public: bool empty(Square s) const; template int count(Color c) const; template const Square* list(Color c) const; - int total_piece_count() const; // Castling int can_castle(Color c) const; @@ -115,7 +117,7 @@ public: // Attacks to/from a given square Bitboard attackers_to(Square s) const; - Bitboard attackers_to(Square s, Bitboard occ) const; + Bitboard attackers_to(Square s, Bitboard occupied) const; Bitboard attacks_from(Piece pc, Square s) const; template Bitboard attacks_from(Square s) const; template Bitboard attacks_from(Square s, Color c) const; @@ -133,12 +135,11 @@ public: // Piece specific bool pawn_passed(Color c, Square s) const; bool pawn_on_7th(Color c) const; - bool bishop_pair(Color c) const; bool opposite_bishops() 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 do_move(Move m, StateInfo& st, const CheckInfo& ci, bool givesCheck); void undo_move(Move m); void do_null_move(StateInfo& st); void undo_null_move(); @@ -151,12 +152,8 @@ public: Key key() const; Key key_after(Move m) const; Key exclusion_key() const; - Key pawn_key() const; Key material_key() const; - - // Incremental piece-square evaluation - Score psq_score() const; - Value non_pawn_material(Color c) const; + Key pawn_key() const; // Other properties of the position Color side_to_move() const; @@ -168,9 +165,11 @@ public: void set_nodes_searched(uint64_t n); bool is_draw() const; int rule50_count() const; + Score psq_score() const; + Value non_pawn_material(Color c) const; // Position consistency check, for debugging - bool pos_is_ok(int* step = NULL) const; + bool pos_is_ok(int* failedStep = nullptr) const; void flip(); private: @@ -179,7 +178,7 @@ private: void set_castling_right(Color c, Square rfrom); void set_state(StateInfo* si) const; - // Helper functions + // Other helpers Bitboard check_blockers(Color c, Color kingColor) const; void put_piece(Square s, Color c, PieceType pt); void remove_piece(Square s, Color c, PieceType pt); @@ -187,15 +186,13 @@ private: template void do_castling(Square from, Square& to, Square& rfrom, Square& rto); - // Board and pieces + // Data members 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 castlingRightsMask[SQUARE_NB]; Square castlingRookSquare[CASTLING_RIGHT_NB]; Bitboard castlingPath[CASTLING_RIGHT_NB]; @@ -208,12 +205,12 @@ private: bool chess960; }; -inline uint64_t Position::nodes_searched() const { - return nodes; +inline Color Position::side_to_move() const { + return sideToMove; } -inline void Position::set_nodes_searched(uint64_t n) { - nodes = n; +inline bool Position::empty(Square s) const { + return board[s] == NO_PIECE; } inline Piece Position::piece_on(Square s) const { @@ -224,14 +221,6 @@ inline Piece Position::moved_piece(Move m) const { return board[from_sq(m)]; } -inline bool Position::empty(Square s) const { - return board[s] == NO_PIECE; -} - -inline Color Position::side_to_move() const { - return sideToMove; -} - inline Bitboard Position::pieces() const { return byTypeBB[ALL_PIECES]; } @@ -264,14 +253,14 @@ template inline const Square* Position::list(Color c) const { return pieceList[c][Pt]; } -inline Square Position::ep_square() const { - return st->epSquare; -} - inline Square Position::king_square(Color c) const { return pieceList[c][KING][0]; } +inline Square Position::ep_square() const { + return st->epSquare; +} + inline int Position::can_castle(CastlingRight cr) const { return st->castlingRights & cr; } @@ -290,7 +279,6 @@ inline Square Position::castling_rook_square(CastlingRight cr) const { template inline Bitboard Position::attacks_from(Square s) const { - return Pt == BISHOP || Pt == ROOK ? attacks_bb(s, byTypeBB[ALL_PIECES]) : Pt == QUEEN ? attacks_from(s) | attacks_from(s) : StepAttacksBB[Pt][s]; @@ -347,7 +335,7 @@ inline Score Position::psq_score() const { } inline Value Position::non_pawn_material(Color c) const { - return st->npMaterial[c]; + return st->nonPawnMaterial[c]; } inline int Position::game_ply() const { @@ -358,23 +346,20 @@ inline int Position::rule50_count() const { return st->rule50; } -inline int Position::total_piece_count() const { - return HasPopCnt ? popcount(pieces()) : pieceCount[WHITE][ALL_PIECES]; +inline uint64_t Position::nodes_searched() const { + return nodes; } -inline bool Position::opposite_bishops() const { +inline void Position::set_nodes_searched(uint64_t n) { + nodes = n; +} +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::bishop_pair(Color c) const { - - return pieceCount[c][BISHOP] >= 2 - && opposite_colors(pieceList[c][BISHOP][0], pieceList[c][BISHOP][1]); -} - inline bool Position::pawn_on_7th(Color c) const { return pieces(c, PAWN) & rank_bb(relative_rank(c, RANK_7)); } @@ -391,7 +376,7 @@ inline bool Position::capture_or_promotion(Move m) const { inline bool Position::capture(Move m) const { - // Note that castling is encoded as "king captures the rook" + // Castling is encoded as "king captures the rook" assert(is_ok(m)); return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == ENPASSANT; } @@ -412,14 +397,13 @@ inline void Position::put_piece(Square s, Color c, PieceType pt) { byColorBB[c] |= s; index[s] = pieceCount[c][pt]++; pieceList[c][pt][index[s]] = s; - if (!HasPopCnt) - pieceCount[WHITE][ALL_PIECES]++; + pieceCount[c][ALL_PIECES]++; } inline void Position::move_piece(Square from, Square to, Color c, PieceType pt) { - // index[from] is not updated and becomes stale. This works as long - // as index[] is accessed just by known occupied squares. + // index[from] is not updated and becomes stale. This works as long as index[] + // is accessed just by known occupied squares. Bitboard from_to_bb = SquareBB[from] ^ SquareBB[to]; byTypeBB[ALL_PIECES] ^= from_to_bb; byTypeBB[pt] ^= from_to_bb; @@ -439,13 +423,12 @@ inline void Position::remove_piece(Square s, Color c, PieceType pt) { byTypeBB[ALL_PIECES] ^= s; byTypeBB[pt] ^= s; byColorBB[c] ^= s; - /* board[s] = NO_PIECE; */ // Not needed, will be overwritten by capturing + /* board[s] = NO_PIECE; Not needed, overwritten by the capturing one */ Square lastSquare = pieceList[c][pt][--pieceCount[c][pt]]; index[lastSquare] = index[s]; pieceList[c][pt][index[lastSquare]] = lastSquare; pieceList[c][pt][pieceCount[c][pt]] = SQ_NONE; - if (!HasPopCnt) - pieceCount[WHITE][ALL_PIECES]--; + pieceCount[c][ALL_PIECES]--; } #endif // #ifndef POSITION_H_INCLUDED