X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=2361132fac4e5596cbb08ca369c7fd7364c0d614;hp=3947180f6f6528a404e6fc48d6b0d4af150ff128;hb=e06a117d5e78ec4edc051f2b161d36559f784d37;hpb=3184852bdce27e387852f4e250c3c5b502706cb3 diff --git a/src/position.h b/src/position.h index 3947180f..2361132f 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) 2015-2017 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 @@ -60,34 +46,37 @@ 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]; }; +// 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&); - public: static void init(); - Position() = default; // To define the global object RootPos + Position() = default; 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 + 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); + Position& set(const std::string& code, Color c, StateInfo* si); const std::string fen() const; // Position representation @@ -98,11 +87,12 @@ 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 int count() const; + template const Square* squares(Color c) const; + template Square square(Color c) const; // Castling int can_castle(Color c) const; @@ -114,44 +104,43 @@ 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; Bitboard attackers_to(Square s, Bitboard occupied) const; - Bitboard attacks_from(Piece pc, Square s) const; + Bitboard attacks_from(PieceType pt, 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 givesCheck); + void do_move(Move m, StateInfo& newSt); + void do_move(Move m, StateInfo& newSt, bool givesCheck); void undo_move(Move m); - void do_null_move(StateInfo& st); + void do_null_move(StateInfo& newSt); 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; @@ -162,11 +151,11 @@ 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; + bool is_draw(int ply) const; int rule50_count() const; Score psq_score() const; Value non_pawn_material(Color c) const; + Value non_pawn_material() const; // Position consistency check, for debugging bool pos_is_ok(int* failedStep = nullptr) const; @@ -174,29 +163,27 @@ public: 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; @@ -205,6 +192,8 @@ private: bool chess960; }; +extern std::ostream& operator<<(std::ostream& os, const Position& pos); + inline Color Position::side_to_move() const { return sideToMove; } @@ -246,15 +235,20 @@ 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 int Position::count() const { + return pieceCount[make_piece(WHITE, Pt)] + pieceCount[make_piece(BLACK, Pt)]; } -inline Square Position::king_square(Color c) const { - return pieceList[c][KING][0]; +template inline const Square* Position::squares(Color c) const { + return pieceList[make_piece(c, Pt)]; +} + +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 { @@ -279,18 +273,19 @@ inline Square Position::castling_rook_square(CastlingRight cr) const { template inline Bitboard Position::attacks_from(Square s) const { + assert(Pt != PAWN); return Pt == BISHOP || Pt == ROOK ? attacks_bb(s, byTypeBB[ALL_PIECES]) : Pt == QUEEN ? attacks_from(s) | attacks_from(s) - : StepAttacksBB[Pt][s]; + : PseudoAttacks[Pt][s]; } template<> inline Bitboard Position::attacks_from(Square s, Color c) const { - return StepAttacksBB[make_piece(c, PAWN)][s]; + return PawnAttacks[c][s]; } -inline Bitboard Position::attacks_from(Piece pc, Square s) const { - return attacks_bb(pc, s, byTypeBB[ALL_PIECES]); +inline Bitboard Position::attacks_from(PieceType pt, Square s) const { + return attacks_bb(pt, s, byTypeBB[ALL_PIECES]); } inline Bitboard Position::attackers_to(Square s) const { @@ -302,11 +297,15 @@ 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 { @@ -338,6 +337,10 @@ inline Value Position::non_pawn_material(Color c) const { return st->nonPawnMaterial[c]; } +inline Value Position::non_pawn_material() const { + return st->nonPawnMaterial[WHITE] + st->nonPawnMaterial[BLACK]; +} + inline int Position::game_ply() const { return gamePly; } @@ -350,18 +353,10 @@ 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 { @@ -369,66 +364,68 @@ 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) { +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 invariant to a do_move() + undo_move() sequence. + byTypeBB[ALL_PIECES] ^= 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[pc][--pieceCount[pc]]; + index[lastSquare] = index[s]; + 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[pt] ^= from_to_bb; - byColorBB[c] ^= from_to_bb; + byTypeBB[type_of(pc)] ^= from_to_bb; + byColorBB[color_of(pc)] ^= from_to_bb; board[from] = NO_PIECE; - board[to] = make_piece(c, pt); + board[to] = pc; index[to] = index[from]; - pieceList[c][pt][index[to]] = to; + pieceList[pc][index[to]] = to; } -inline void Position::remove_piece(Square s, Color c, PieceType pt) { - - // 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. - byTypeBB[ALL_PIECES] ^= s; - byTypeBB[pt] ^= s; - byColorBB[c] ^= s; - /* 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; - pieceCount[c][ALL_PIECES]--; +inline void Position::do_move(Move m, StateInfo& newSt) { + do_move(m, newSt, gives_check(m)); } #endif // #ifndef POSITION_H_INCLUDED