X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=9aa4c44533cdf5f536b8232ea3a186245120b2e4;hp=86acd20d0eb7a174b779147f8e992dce9ff4a7c5;hb=ca677526452823d1fe89543762edb66684e7bdc7;hpb=f53aea45e3230239d358d4d35357c9ee6bf6fb54 diff --git a/src/position.h b/src/position.h index 86acd20d..9aa4c445 100644 --- a/src/position.h +++ b/src/position.h @@ -2,6 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -21,28 +22,13 @@ #define POSITION_H_INCLUDED #include -#include // For offsetof() +#include +#include // For std::unique_ptr #include #include "bitboard.h" #include "types.h" -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&); - - Bitboard dcCandidates; - Bitboard pinned; - Bitboard checkSq[PIECE_TYPE_NB]; - Square ksq; -}; - /// 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 @@ -60,40 +46,36 @@ struct StateInfo { Score psq; Square epSquare; - // Not copied when making a move + // Not copied when making a move (will be recomputed anyhow) Key key; Bitboard checkersBB; - PieceType capturedType; + Piece capturedPiece; StateInfo* previous; + Bitboard blockersForKing[COLOR_NB]; + Bitboard pinnersForKing[COLOR_NB]; + Bitboard checkSquares[PIECE_TYPE_NB]; }; - -/// When making a move the current StateInfo up to 'key' excluded is copied to -/// the new one. Here we calculate the quad words (64 bit) needed to be copied. -const size_t StateCopySize64 = offsetof(StateInfo, key) / sizeof(uint64_t) + 1; +// In a std::deque references to elements are unaffected upon resizing +typedef std::unique_ptr> StateListPtr; /// 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 Thread; class Position { - - friend std::ostream& operator<<(std::ostream&, const Position&); - - Position(const Position&); // Disable the default copy constructor - public: static void init(); - Position() {} // To define the global object RootPos - 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 + Position() = default; + Position(const Position&) = delete; + Position& operator=(const Position&) = delete; // FEN string input/output - void set(const std::string& fenStr, bool isChess960, Thread* th); + Position& set(const std::string& fenStr, bool isChess960, StateInfo* si, Thread* th); const std::string fen() const; // Position representation @@ -104,11 +86,11 @@ public: 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 empty(Square s) const; template int count(Color c) const; - template const Square* list(Color c) const; + template const Square* squares(Color c) const; + template Square square(Color c) const; // Castling int can_castle(Color c) const; @@ -120,6 +102,7 @@ public: Bitboard checkers() const; Bitboard discovered_check_candidates() const; Bitboard pinned_pieces(Color c) const; + Bitboard check_squares(PieceType pt) const; // Attacks to/from a given square Bitboard attackers_to(Square s) const; @@ -127,37 +110,34 @@ public: Bitboard attacks_from(Piece pc, Square s) const; template Bitboard attacks_from(Square s) const; template Bitboard attacks_from(Square s, Color c) const; + Bitboard slider_blockers(Bitboard sliders, Square s, Bitboard& pinners) const; // Properties of moves - bool legal(Move m, Bitboard pinned) const; + bool legal(Move m) const; bool pseudo_legal(const Move m) const; bool capture(Move m) const; bool capture_or_promotion(Move m) const; - bool gives_check(Move m, const CheckInfo& ci) const; + bool gives_check(Move m) const; bool advanced_pawn_push(Move m) const; Piece moved_piece(Move m) const; - PieceType captured_piece_type() const; + Piece captured_piece() const; // Piece specific bool pawn_passed(Color c, Square s) const; - bool pawn_on_7th(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, bool givesCheck); void undo_move(Move m); void do_null_move(StateInfo& st); void undo_null_move(); - // Static exchange evaluation - Value see(Move m) const; - Value see_sign(Move m) const; + // Static Exchange Evaluation + bool see_ge(Move m, Value value) const; // Accessing hash keys Key key() const; Key key_after(Move m) const; - Key exclusion_key() const; Key material_key() const; Key pawn_key() const; @@ -168,41 +148,38 @@ public: bool is_chess960() const; Thread* this_thread() const; uint64_t nodes_searched() const; - 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 = nullptr) const; + bool pos_is_ok(int* failedStep = nullptr) const; void flip(); private: // Initialization helpers (used while setting up a position) - void clear(); void set_castling_right(Color c, Square rfrom); void set_state(StateInfo* si) const; + void set_check_info(StateInfo* si) const; // 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); - void move_piece(Square from, Square to, Color c, PieceType pt); + void put_piece(Piece pc, Square s); + void remove_piece(Piece pc, Square s); + void move_piece(Piece pc, Square from, Square to); template - void do_castling(Square from, Square& to, Square& rfrom, Square& rto); + void do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto); // 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 pieceCount[PIECE_NB]; + Square pieceList[PIECE_NB][16]; int index[SQUARE_NB]; int castlingRightsMask[SQUARE_NB]; Square castlingRookSquare[CASTLING_RIGHT_NB]; Bitboard castlingPath[CASTLING_RIGHT_NB]; - StateInfo startState; uint64_t nodes; int gamePly; Color sideToMove; @@ -211,6 +188,8 @@ private: bool chess960; }; +extern std::ostream& operator<<(std::ostream& os, const Position& pos); + inline Color Position::side_to_move() const { return sideToMove; } @@ -252,15 +231,16 @@ inline Bitboard Position::pieces(Color c, PieceType pt1, PieceType pt2) const { } template inline int Position::count(Color c) const { - return pieceCount[c][Pt]; + return pieceCount[make_piece(c, Pt)]; } -template inline const Square* Position::list(Color c) const { - return pieceList[c][Pt]; +template inline const Square* Position::squares(Color c) const { + return pieceList[make_piece(c, Pt)]; } -inline Square Position::king_square(Color c) const { - return pieceList[c][KING][0]; +template inline Square Position::square(Color c) const { + assert(pieceCount[make_piece(c, Pt)] == 1); + return pieceList[make_piece(c, Pt)][0]; } inline Square Position::ep_square() const { @@ -308,11 +288,15 @@ inline Bitboard Position::checkers() const { } inline Bitboard Position::discovered_check_candidates() const { - return check_blockers(sideToMove, ~sideToMove); + return st->blockersForKing[~sideToMove] & pieces(sideToMove); } inline Bitboard Position::pinned_pieces(Color c) const { - return check_blockers(c, c); + return st->blockersForKing[c] & pieces(c); +} + +inline Bitboard Position::check_squares(PieceType pt) const { + return st->checkSquares[pt]; } inline bool Position::pawn_passed(Color c, Square s) const { @@ -356,18 +340,10 @@ inline uint64_t Position::nodes_searched() const { return nodes; } -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::pawn_on_7th(Color c) const { - return pieces(c, PAWN) & rank_bb(relative_rank(c, RANK_7)); + return pieceCount[W_BISHOP] == 1 + && pieceCount[B_BISHOP] == 1 + && opposite_colors(square(WHITE), square(BLACK)); } inline bool Position::is_chess960() const { @@ -375,66 +351,64 @@ inline bool Position::is_chess960() const { } inline bool Position::capture_or_promotion(Move m) const { - assert(is_ok(m)); return type_of(m) != NORMAL ? type_of(m) != CASTLING : !empty(to_sq(m)); } inline bool Position::capture(Move m) const { - - // Castling is encoded as "king captures the rook" assert(is_ok(m)); + // Castling is encoded as "king captures rook" return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == ENPASSANT; } -inline PieceType Position::captured_piece_type() const { - return st->capturedType; +inline Piece Position::captured_piece() const { + return st->capturedPiece; } inline Thread* Position::this_thread() const { return thisThread; } -inline void Position::put_piece(Square s, Color c, PieceType pt) { +inline void Position::put_piece(Piece pc, Square s) { - board[s] = make_piece(c, pt); + board[s] = pc; byTypeBB[ALL_PIECES] |= s; - byTypeBB[pt] |= s; - byColorBB[c] |= s; - index[s] = pieceCount[c][pt]++; - pieceList[c][pt][index[s]] = s; - pieceCount[c][ALL_PIECES]++; + byTypeBB[type_of(pc)] |= s; + byColorBB[color_of(pc)] |= s; + index[s] = pieceCount[pc]++; + pieceList[pc][index[s]] = s; + pieceCount[make_piece(color_of(pc), 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. - Bitboard from_to_bb = SquareBB[from] ^ SquareBB[to]; - byTypeBB[ALL_PIECES] ^= from_to_bb; - byTypeBB[pt] ^= from_to_bb; - byColorBB[c] ^= from_to_bb; - board[from] = NO_PIECE; - board[to] = make_piece(c, pt); - index[to] = index[from]; - pieceList[c][pt][index[to]] = to; -} - -inline void Position::remove_piece(Square s, Color c, PieceType pt) { +inline void Position::remove_piece(Piece pc, Square s) { // WARNING: This is not a reversible operation. If we remove a piece in // do_move() and then replace it in undo_move() we will put it at the end of // the list and not in its original place, it means index[] and pieceList[] - // are not guaranteed to be invariant to a do_move() + undo_move() sequence. + // are not invariant to a do_move() + undo_move() sequence. byTypeBB[ALL_PIECES] ^= s; - byTypeBB[pt] ^= s; - byColorBB[c] ^= s; + byTypeBB[type_of(pc)] ^= s; + byColorBB[color_of(pc)] ^= s; /* board[s] = NO_PIECE; Not needed, overwritten by the capturing one */ - Square lastSquare = pieceList[c][pt][--pieceCount[c][pt]]; + Square lastSquare = pieceList[pc][--pieceCount[pc]]; index[lastSquare] = index[s]; - pieceList[c][pt][index[lastSquare]] = lastSquare; - pieceList[c][pt][pieceCount[c][pt]] = SQ_NONE; - pieceCount[c][ALL_PIECES]--; + pieceList[pc][index[lastSquare]] = lastSquare; + pieceList[pc][pieceCount[pc]] = SQ_NONE; + pieceCount[make_piece(color_of(pc), ALL_PIECES)]--; +} + +inline void Position::move_piece(Piece pc, Square from, Square to) { + + // 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[type_of(pc)] ^= from_to_bb; + byColorBB[color_of(pc)] ^= from_to_bb; + board[from] = NO_PIECE; + board[to] = pc; + index[to] = index[from]; + pieceList[pc][index[to]] = to; } #endif // #ifndef POSITION_H_INCLUDED