X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=2106414ba2dd4f3475bf5cb42e2149539e939abf;hp=68fc508e16793474d291eeeef98607f6e7b124b9;hb=4ae5a7b45a430aea5f4b21f9455b4db74ed1c44a;hpb=ca6c9f85a5c3a45a248716b8fe68821b20eee201 diff --git a/src/position.h b/src/position.h index 68fc508e..2106414b 100644 --- a/src/position.h +++ b/src/position.h @@ -2,7 +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 + Copyright (C) 2015-2019 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 @@ -22,25 +22,13 @@ #define POSITION_H_INCLUDED #include -#include // For offsetof() #include -#include // For std::unique_ptr +#include // For std::unique_ptr #include -#include #include "bitboard.h" #include "types.h" -class Position; -class Thread; - -namespace PSQT { - - extern Score psq[PIECE_NB][SQUARE_NB]; - - void init(); -} - /// 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 @@ -55,19 +43,23 @@ struct StateInfo { int castlingRights; int rule50; int pliesFromNull; - Score psq; Square epSquare; - // Not copied when making a move + // Not copied when making a move (will be recomputed anyhow) + int repetition; Key key; Bitboard checkersBB; Piece capturedPiece; StateInfo* previous; Bitboard blockersForKing[COLOR_NB]; + Bitboard pinners[COLOR_NB]; Bitboard checkSquares[PIECE_TYPE_NB]; }; -// In a std::deque references to elements are unaffected upon resizing +/// A list to keep track of the position states along the setup moves (from the +/// start position to the position just before the search starts). Needed by +/// 'draw by repetition' detection. Use a std::deque because pointers to +/// elements are not invalidated upon list resizing. typedef std::unique_ptr> StateListPtr; @@ -75,9 +67,9 @@ typedef std::unique_ptr> StateListPtr; /// 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 { - public: static void init(); @@ -87,6 +79,7 @@ public: // FEN string input/output 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 @@ -100,28 +93,30 @@ public: Square ep_square() const; bool empty(Square s) const; template int count(Color c) const; + template int count() const; template const Square* squares(Color c) const; template Square square(Color c) const; + bool is_on_semiopen_file(Color c, Square s) const; // Castling - int can_castle(Color c) const; - int can_castle(CastlingRight cr) const; + int castling_rights(Color c) const; + bool can_castle(CastlingRight cr) const; bool castling_impeded(CastlingRight cr) const; Square castling_rook_square(CastlingRight cr) const; // Checking Bitboard checkers() const; - Bitboard discovered_check_candidates() const; - Bitboard pinned_pieces(Color c) const; + Bitboard blockers_for_king(Color c) const; Bitboard check_squares(PieceType pt) const; + bool is_discovery_check_on_king(Color c, Move m) 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) const; + Bitboard slider_blockers(Bitboard sliders, Square s, Bitboard& pinners) const; // Properties of moves bool legal(Move m) const; @@ -136,16 +131,17 @@ public: // Piece specific bool pawn_passed(Color c, Square s) const; bool opposite_bishops() const; + int pawns_on_same_color_squares(Color c, Square s) const; // Doing and undoing moves - void do_move(Move m, StateInfo& st, 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 threshold = VALUE_ZERO) const; // Accessing hash keys Key key() const; @@ -155,19 +151,19 @@ public: // Other properties of the position Color side_to_move() const; - Phase game_phase() const; int game_ply() const; 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; + bool has_game_cycle(int ply) const; + bool has_repeated() 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; + bool pos_is_ok() const; void flip(); private: @@ -193,14 +189,18 @@ private: int castlingRightsMask[SQUARE_NB]; Square castlingRookSquare[CASTLING_RIGHT_NB]; Bitboard castlingPath[CASTLING_RIGHT_NB]; - uint64_t nodes; int gamePly; Color sideToMove; + Score psq; Thread* thisThread; StateInfo* st; bool chess960; }; +namespace PSQT { + extern Score psq[PIECE_NB][SQUARE_NB]; +} + extern std::ostream& operator<<(std::ostream& os, const Position& pos); inline Color Position::side_to_move() const { @@ -247,6 +247,10 @@ template inline int Position::count(Color c) const { return pieceCount[make_piece(c, Pt)]; } +template inline int Position::count() const { + return pieceCount[make_piece(WHITE, Pt)] + pieceCount[make_piece(BLACK, Pt)]; +} + template inline const Square* Position::squares(Color c) const { return pieceList[make_piece(c, Pt)]; } @@ -260,12 +264,16 @@ inline Square Position::ep_square() const { return st->epSquare; } -inline int Position::can_castle(CastlingRight cr) const { +inline bool Position::is_on_semiopen_file(Color c, Square s) const { + return !(pieces(c, PAWN) & file_bb(s)); +} + +inline bool Position::can_castle(CastlingRight cr) const { return st->castlingRights & cr; } -inline int Position::can_castle(Color c) const { - return st->castlingRights & ((WHITE_OO | WHITE_OOO) << (2 * c)); +inline int Position::castling_rights(Color c) const { + return st->castlingRights & (c == WHITE ? WHITE_CASTLING : BLACK_CASTLING); } inline bool Position::castling_impeded(CastlingRight cr) const { @@ -278,18 +286,19 @@ 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 { @@ -300,25 +309,29 @@ inline Bitboard Position::checkers() const { return st->checkersBB; } -inline Bitboard Position::discovered_check_candidates() const { - return st->blockersForKing[~sideToMove] & pieces(sideToMove); -} - -inline Bitboard Position::pinned_pieces(Color c) const { - return st->blockersForKing[c] & pieces(c); +inline Bitboard Position::blockers_for_king(Color c) const { + return st->blockersForKing[c]; } inline Bitboard Position::check_squares(PieceType pt) const { return st->checkSquares[pt]; } +inline bool Position::is_discovery_check_on_king(Color c, Move m) const { + return st->blockersForKing[c] & from_sq(m); +} + inline bool Position::pawn_passed(Color c, Square s) const { - return !(pieces(~c, PAWN) & passed_pawn_mask(c, s)); + return !(pieces(~c, PAWN) & passed_pawn_span(c, s)); } inline bool Position::advanced_pawn_push(Move m) const { return type_of(moved_piece(m)) == PAWN - && relative_rank(sideToMove, from_sq(m)) > RANK_4; + && relative_rank(sideToMove, to_sq(m)) > RANK_5; +} + +inline int Position::pawns_on_same_color_squares(Color c, Square s) const { + return popcount(pieces(c, PAWN) & ((DarkSquares & s) ? DarkSquares : ~DarkSquares)); } inline Key Position::key() const { @@ -334,13 +347,17 @@ inline Key Position::material_key() const { } inline Score Position::psq_score() const { - return st->psq; + return psq; } 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; } @@ -349,14 +366,6 @@ inline int Position::rule50_count() const { return st->rule50; } -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[W_BISHOP] == 1 && pieceCount[B_BISHOP] == 1 @@ -368,15 +377,13 @@ 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; } @@ -397,6 +404,7 @@ inline void Position::put_piece(Piece pc, Square s) { index[s] = pieceCount[pc]++; pieceList[pc][index[s]] = s; pieceCount[make_piece(color_of(pc), ALL_PIECES)]++; + psq += PSQT::psq[pc][s]; } inline void Position::remove_piece(Piece pc, Square s) { @@ -404,7 +412,7 @@ 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[type_of(pc)] ^= s; byColorBB[color_of(pc)] ^= s; @@ -414,20 +422,26 @@ inline void Position::remove_piece(Piece pc, Square s) { pieceList[pc][index[lastSquare]] = lastSquare; pieceList[pc][pieceCount[pc]] = SQ_NONE; pieceCount[make_piece(color_of(pc), ALL_PIECES)]--; + psq -= PSQT::psq[pc][s]; } 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; + Bitboard fromTo = square_bb(from) | square_bb(to); + byTypeBB[ALL_PIECES] ^= fromTo; + byTypeBB[type_of(pc)] ^= fromTo; + byColorBB[color_of(pc)] ^= fromTo; board[from] = NO_PIECE; board[to] = pc; index[to] = index[from]; pieceList[pc][index[to]] = to; + psq += PSQT::psq[pc][to] - PSQT::psq[pc][from]; +} + +inline void Position::do_move(Move m, StateInfo& newSt) { + do_move(m, newSt, gives_check(m)); } #endif // #ifndef POSITION_H_INCLUDED