X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=907357bd1f90ba09f6197f15763248970997965b;hp=12485fbb780fb64026e359bc97cdd271ea9c2599;hb=c549f71f64a29fd06f8537de697bc67fdc642753;hpb=c6f497f09de59ce4889c2045e0e4b6efb3082899 diff --git a/src/position.cpp b/src/position.cpp index 12485fbb..907357bd 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -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) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2012 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 @@ -22,6 +22,7 @@ #include #include #include +#include #include "bitcount.h" #include "movegen.h" @@ -69,7 +70,7 @@ namespace { const Score TempoValue = make_score(48, 22); // To convert a Piece to and from a FEN char - const string PieceToChar(".PNBRQK pnbrqk "); + const string PieceToChar(" PNBRQK pnbrqk ."); } @@ -78,7 +79,7 @@ namespace { CheckInfo::CheckInfo(const Position& pos) { Color them = flip(pos.side_to_move()); - Square ksq = pos.king_square(them); + ksq = pos.king_square(them); pinned = pos.pinned_pieces(); dcCandidates = pos.discovered_check_candidates(); @@ -88,7 +89,7 @@ CheckInfo::CheckInfo(const Position& pos) { checkSq[BISHOP] = pos.attacks_from(ksq); checkSq[ROOK] = pos.attacks_from(ksq); checkSq[QUEEN] = checkSq[BISHOP] | checkSq[ROOK]; - checkSq[KING] = EmptyBoardBB; + checkSq[KING] = 0; } @@ -96,9 +97,11 @@ CheckInfo::CheckInfo(const Position& pos) { /// or the FEN string, we want the new born Position object do not depend /// on any external data so we detach state pointer from the source one. -Position::Position(const Position& pos, int th) { +void Position::copy(const Position& pos, int th) { memcpy(this, &pos, sizeof(Position)); + startState = *st; + st = &startState; threadID = th; nodes = 0; @@ -162,11 +165,11 @@ void Position::from_fen(const string& fenStr, bool isChess960) { // 1. Piece placement while ((fen >> token) && !isspace(token)) { - if (token == '/') - sq -= Square(16); // Jump back of 2 rows + if (isdigit(token)) + sq += Square(token - '0'); // Advance the given number of files - else if (isdigit(token)) - sq += Square(token - '0'); // Skip the given number of files + else if (token == '/') + sq = make_square(FILE_A, rank_of(sq) - Rank(2)); else if ((p = PieceToChar.find(token)) != string::npos) { @@ -189,15 +192,14 @@ void Position::from_fen(const string& fenStr, bool isChess960) { { Square rsq; Color c = islower(token) ? BLACK : WHITE; - Piece rook = make_piece(c, ROOK); token = char(toupper(token)); if (token == 'K') - for (rsq = relative_square(c, SQ_H1); piece_on(rsq) != rook; rsq--) {} + for (rsq = relative_square(c, SQ_H1); type_of(piece_on(rsq)) != ROOK; rsq--) {} else if (token == 'Q') - for (rsq = relative_square(c, SQ_A1); piece_on(rsq) != rook; rsq++) {} + for (rsq = relative_square(c, SQ_A1); type_of(piece_on(rsq)) != ROOK; rsq++) {} else if (token >= 'A' && token <= 'H') rsq = make_square(File(token - 'A'), relative_rank(c, RANK_1)); @@ -205,7 +207,7 @@ void Position::from_fen(const string& fenStr, bool isChess960) { else continue; - set_castle_right(king_square(c), rsq); + set_castle_right(c, rsq); } // 4. En passant square. Ignore if no pawn capture is possible @@ -223,7 +225,7 @@ void Position::from_fen(const string& fenStr, bool isChess960) { // Convert from fullmove starting from 1 to ply starting from 0, // handle also common incorrect FEN with fullmove = 0. - startPosPly = Max(2 * (startPosPly - 1), 0) + int(sideToMove == BLACK); + startPosPly = std::max(2 * (startPosPly - 1), 0) + int(sideToMove == BLACK); st->key = compute_key(); st->pawnKey = compute_pawn_key(); @@ -239,14 +241,14 @@ void Position::from_fen(const string& fenStr, bool isChess960) { /// Position::set_castle_right() is an helper function used to set castling -/// rights given the corresponding king and rook starting squares. +/// rights given the corresponding color and the rook starting square. -void Position::set_castle_right(Square ksq, Square rsq) { +void Position::set_castle_right(Color c, Square rsq) { - int f = (rsq < ksq ? WHITE_OOO : WHITE_OO) << color_of(piece_on(ksq)); + int f = (rsq < king_square(c) ? WHITE_OOO : WHITE_OO) << c; st->castleRights |= f; - castleRightsMask[ksq] ^= f; + castleRightsMask[king_square(c)] ^= f; castleRightsMask[rsq] ^= f; castleRookSquare[f] = rsq; } @@ -335,8 +337,8 @@ void Position::print(Move move) const { Piece piece = piece_on(sq); char c = (color_of(piece) == BLACK ? '=' : ' '); - if (piece == PIECE_NONE && color_of(sq) == DARK) - piece = PIECE_NONE_DARK_SQ; + if (piece == NO_PIECE && !opposite_colors(sq, SQ_A1)) + piece++; // Index the dot cout << c << PieceToChar[piece] << c << '|'; } @@ -358,8 +360,8 @@ Bitboard Position::hidden_checkers() const { Square ksq = king_square(FindPinned ? sideToMove : flip(sideToMove)); // Pinners are sliders, that give check when candidate pinned is removed - pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq]) - | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]); + pinners &= (pieces(ROOK, QUEEN) & PseudoAttacks[ROOK][ksq]) + | (pieces(BISHOP, QUEEN) & PseudoAttacks[BISHOP][ksq]); while (pinners) { @@ -398,12 +400,12 @@ Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { assert(square_is_ok(s)); - switch (p) + switch (type_of(p)) { - case WB: case BB: return bishop_attacks_bb(s, occ); - case WR: case BR: return rook_attacks_bb(s, occ); - case WQ: case BQ: return bishop_attacks_bb(s, occ) | rook_attacks_bb(s, occ); - default: return StepAttacksBB[p][s]; + case BISHOP: return bishop_attacks_bb(s, occ); + case ROOK : return rook_attacks_bb(s, occ); + case QUEEN : return bishop_attacks_bb(s, occ) | rook_attacks_bb(s, occ); + default : return StepAttacksBB[p][s]; } } @@ -417,8 +419,8 @@ bool Position::move_attacks_square(Move m, Square s) const { assert(square_is_ok(s)); Bitboard occ, xray; - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); Piece piece = piece_on(from); assert(!square_is_empty(from)); @@ -448,7 +450,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(pinned == pinned_pieces()); Color us = side_to_move(); - Square from = move_from(m); + Square from = from_sq(m); assert(color_of(piece_on(from)) == us); assert(piece_on(king_square(us)) == make_piece(us, KING)); @@ -459,7 +461,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { if (is_enpassant(m)) { Color them = flip(us); - Square to = move_to(m); + Square to = to_sq(m); Square capsq = to + pawn_push(them); Square ksq = king_square(us); Bitboard b = occupied_squares(); @@ -467,7 +469,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(to == ep_square()); assert(piece_on(from) == make_piece(us, PAWN)); assert(piece_on(capsq) == make_piece(them, PAWN)); - assert(piece_on(to) == PIECE_NONE); + assert(piece_on(to) == NO_PIECE); clear_bit(&b, from); clear_bit(&b, capsq); @@ -481,13 +483,13 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { // square is attacked by the opponent. Castling moves are checked // for legality during move generation. if (type_of(piece_on(from)) == KING) - return is_castle(m) || !(attackers_to(move_to(m)) & pieces(flip(us))); + return is_castle(m) || !(attackers_to(to_sq(m)) & pieces(flip(us))); // A non-king move is legal if and only if it is not pinned or it // is moving along the ray towards or away from the king. return !pinned || !bit_is_set(pinned, from) - || squares_aligned(from, move_to(m), king_square(us)); + || squares_aligned(from, to_sq(m), king_square(us)); } @@ -513,8 +515,8 @@ bool Position::is_pseudo_legal(const Move m) const { Color us = sideToMove; Color them = flip(sideToMove); - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); Piece pc = piece_on(from); // Use a slower but simpler function for uncommon cases @@ -522,12 +524,12 @@ bool Position::is_pseudo_legal(const Move m) const { return move_is_legal(m); // Is not a promotion, so promotion piece must be empty - if (promotion_piece_type(m) - 2 != PIECE_TYPE_NONE) + if (promotion_piece_type(m) - 2 != NO_PIECE_TYPE) return false; // If the from square is not occupied by a piece belonging to the side to // move, the move is obviously not legal. - if (pc == PIECE_NONE || color_of(pc) != us) + if (pc == NO_PIECE || color_of(pc) != us) return false; // The destination square cannot be occupied by a friendly piece @@ -610,7 +612,7 @@ bool Position::is_pseudo_legal(const Move m) const { { Bitboard b = occupied_squares(); clear_bit(&b, from); - if (attackers_to(move_to(m), b) & pieces(flip(us))) + if (attackers_to(to_sq(m), b) & pieces(flip(us))) return false; } else @@ -623,7 +625,7 @@ bool Position::is_pseudo_legal(const Move m) const { // Our move must be a blocking evasion or a capture of the checking piece target = squares_between(checksq, king_square(us)) | checkers(); - if (!bit_is_set(target, move_to(m))) + if (!bit_is_set(target, to_sq(m))) return false; } } @@ -638,10 +640,10 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { assert(is_ok(m)); assert(ci.dcCandidates == discovered_check_candidates()); - assert(color_of(piece_on(move_from(m))) == side_to_move()); + assert(color_of(piece_moved(m)) == side_to_move()); - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); PieceType pt = type_of(piece_on(from)); // Direct check ? @@ -728,7 +730,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI assert(&newSt != st); nodes++; - Key key = st->key; + Key k = st->key; // Copy some fields of old state to our new StateInfo object except the ones // which are recalculated from scratch anyway, then switch our state pointer @@ -747,7 +749,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI st = &newSt; // Update side to move - key ^= zobSideToMove; + k ^= zobSideToMove; // Increment the 50 moves rule draw counter. Resetting it to zero in the // case of non-reversible moves is taken care of later. @@ -756,15 +758,15 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI if (is_castle(m)) { - st->key = key; + st->key = k; do_castle_move(m); return; } Color us = side_to_move(); Color them = flip(us); - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); Piece piece = piece_on(from); PieceType pt = type_of(piece); PieceType capture = is_enpassant(m) ? PAWN : type_of(piece_on(to)); @@ -788,10 +790,10 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI assert(pt == PAWN); assert(to == st->epSquare); assert(relative_rank(us, to) == RANK_6); - assert(piece_on(to) == PIECE_NONE); + assert(piece_on(to) == NO_PIECE); assert(piece_on(capsq) == make_piece(them, PAWN)); - board[capsq] = PIECE_NONE; + board[capsq] = NO_PIECE; } st->pawnKey ^= zobrist[them][PAWN][capsq]; @@ -817,7 +819,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI pieceList[them][capture][pieceCount[them][capture]] = SQ_NONE; // Update hash keys - key ^= zobrist[them][capture][capsq]; + k ^= zobrist[them][capture][capsq]; st->materialKey ^= zobrist[them][capture][pieceCount[them][capture]]; // Update incremental scores @@ -828,12 +830,12 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI } // Update hash key - key ^= zobrist[us][pt][from] ^ zobrist[us][pt][to]; + k ^= zobrist[us][pt][from] ^ zobrist[us][pt][to]; // Reset en passant square if (st->epSquare != SQ_NONE) { - key ^= zobEp[st->epSquare]; + k ^= zobEp[st->epSquare]; st->epSquare = SQ_NONE; } @@ -841,13 +843,13 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI if ( st->castleRights != CASTLES_NONE && (castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES) { - key ^= zobCastle[st->castleRights]; + k ^= zobCastle[st->castleRights]; st->castleRights &= castleRightsMask[from] & castleRightsMask[to]; - key ^= zobCastle[st->castleRights]; + k ^= zobCastle[st->castleRights]; } // Prefetch TT access as soon as we know key is updated - prefetch((char*)TT.first_entry(key)); + prefetch((char*)TT.first_entry(k)); // Move the piece Bitboard move_bb = make_move_bb(from, to); @@ -856,7 +858,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI do_move_bb(&occupied, move_bb); board[to] = board[from]; - board[from] = PIECE_NONE; + board[from] = NO_PIECE; // Update piece lists, index[from] is not updated and becomes stale. This // works as long as index[] is accessed just by known occupied squares. @@ -871,7 +873,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI && (attacks_from(from + pawn_push(us), us) & pieces(PAWN, them))) { st->epSquare = Square((from + to) / 2); - key ^= zobEp[st->epSquare]; + k ^= zobEp[st->epSquare]; } if (is_promotion(m)) @@ -896,7 +898,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI pieceList[us][promotion][index[to]] = to; // Update hash keys - key ^= zobrist[us][PAWN][to] ^ zobrist[us][promotion][to]; + k ^= zobrist[us][PAWN][to] ^ zobrist[us][promotion][to]; st->pawnKey ^= zobrist[us][PAWN][to]; st->materialKey ^= zobrist[us][promotion][pieceCount[us][promotion]++] ^ zobrist[us][PAWN][pieceCount[us][PAWN]]; @@ -927,10 +929,10 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI st->capturedType = capture; // Update the key with the final value - st->key = key; + st->key = k; // Update checkers bitboard, piece must be already moved - st->checkersBB = EmptyBoardBB; + st->checkersBB = 0; if (moveIsCheck) { @@ -979,8 +981,8 @@ void Position::undo_move(Move m) { Color us = side_to_move(); Color them = flip(us); - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); Piece piece = piece_on(to); PieceType pt = type_of(piece); PieceType capture = st->capturedType; @@ -1021,7 +1023,7 @@ void Position::undo_move(Move m) { do_move_bb(&occupied, move_bb); board[from] = board[to]; - board[to] = PIECE_NONE; + board[to] = NO_PIECE; // Update piece lists, index[to] is not updated and becomes stale. This // works as long as index[] is accessed just by known occupied squares. @@ -1039,7 +1041,7 @@ void Position::undo_move(Move m) { assert(pt == PAWN); assert(to == st->previous->epSquare); assert(relative_rank(us, to) == RANK_6); - assert(piece_on(capsq) == PIECE_NONE); + assert(piece_on(capsq) == NO_PIECE); } // Restore the captured piece @@ -1074,8 +1076,8 @@ void Position::do_castle_move(Move m) { Square kto, kfrom, rfrom, rto, kAfter, rAfter; Color us = side_to_move(); - Square kBefore = move_from(m); - Square rBefore = move_to(m); + Square kBefore = from_sq(m); + Square rBefore = to_sq(m); // Find after-castle squares for king and rook if (rBefore > kBefore) // O-O @@ -1117,7 +1119,7 @@ void Position::do_castle_move(Move m) { // Update board Piece king = make_piece(us, KING); Piece rook = make_piece(us, ROOK); - board[kfrom] = board[rfrom] = PIECE_NONE; + board[kfrom] = board[rfrom] = NO_PIECE; board[kto] = king; board[rto] = rook; @@ -1131,7 +1133,7 @@ void Position::do_castle_move(Move m) { if (Do) { // Reset capture field - st->capturedType = PIECE_TYPE_NONE; + st->capturedType = NO_PIECE_TYPE; // Update incremental scores st->value += pst_delta(king, kfrom, kto); @@ -1225,8 +1227,8 @@ int Position::see_sign(Move m) const { assert(is_ok(m)); - Square from = move_from(m); - Square to = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); // Early return if SEE cannot be negative because captured piece value // is not less then capturing one. Note that king moves always return @@ -1253,8 +1255,8 @@ int Position::see(Move m) const { if (is_castle(m)) return 0; - from = move_from(m); - to = move_to(m); + from = from_sq(m); + to = to_sq(m); capturedType = type_of(piece_on(to)); occ = occupied_squares(); @@ -1263,7 +1265,7 @@ int Position::see(Move m) const { { Square capQq = to - pawn_push(side_to_move()); - assert(capturedType == PIECE_TYPE_NONE); + assert(capturedType == NO_PIECE_TYPE); assert(type_of(piece_on(capQq)) == PAWN); // Remove the captured pawn @@ -1330,7 +1332,7 @@ int Position::see(Move m) const { // Having built the swap list, we negamax through it to find the best // achievable score from the point of view of the side to move. while (--slIndex) - swapList[slIndex-1] = Min(-swapList[slIndex], swapList[slIndex-1]); + swapList[slIndex-1] = std::min(-swapList[slIndex], swapList[slIndex-1]); return swapList[0]; } @@ -1356,7 +1358,7 @@ void Position::clear() { for (Square sq = SQ_A1; sq <= SQ_H8; sq++) { - board[sq] = PIECE_NONE; + board[sq] = NO_PIECE; castleRightsMask[sq] = ALL_CASTLES; } sideToMove = WHITE; @@ -1496,13 +1498,13 @@ bool Position::is_draw() const { return true; // Draw by the 50 moves rule? - if (st->rule50 > 99 && !is_mate()) + if (st->rule50 > 99 && (!in_check() || MoveList(*this).size())) return true; // Draw by repetition? if (!SkipRepetition) { - int i = 4, e = Min(st->rule50, st->pliesFromNull); + int i = 4, e = std::min(st->rule50, st->pliesFromNull); if (i <= e) { @@ -1528,15 +1530,6 @@ template bool Position::is_draw() const; template bool Position::is_draw() const; -/// Position::is_mate() returns true or false depending on whether the -/// side to move is checkmated. - -bool Position::is_mate() const { - - return in_check() && !MoveList(*this).size(); -} - - /// Position::init() is a static member function which initializes at startup /// the various arrays used to compute hash keys and the piece square tables. /// The latter is a two-step operation: First, the white halves of the tables @@ -1561,7 +1554,7 @@ void Position::init() { zobSideToMove = rk.rand(); zobExclusion = rk.rand(); - for (Piece p = WP; p <= WK; p++) + for (Piece p = W_PAWN; p <= W_KING; p++) { Score ps = make_score(PieceValueMidgame[p], PieceValueEndgame[p]); @@ -1595,13 +1588,13 @@ void Position::flip_me() { // Castling rights if (pos.can_castle(WHITE_OO)) - set_castle_right(king_square(BLACK), flip(pos.castle_rook_square(WHITE_OO))); + set_castle_right(BLACK, flip(pos.castle_rook_square(WHITE_OO))); if (pos.can_castle(WHITE_OOO)) - set_castle_right(king_square(BLACK), flip(pos.castle_rook_square(WHITE_OOO))); + set_castle_right(BLACK, flip(pos.castle_rook_square(WHITE_OOO))); if (pos.can_castle(BLACK_OO)) - set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OO))); + set_castle_right(WHITE, flip(pos.castle_rook_square(BLACK_OO))); if (pos.can_castle(BLACK_OOO)) - set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OOO))); + set_castle_right(WHITE, flip(pos.castle_rook_square(BLACK_OOO))); // En passant square if (pos.st->epSquare != SQ_NONE) @@ -1655,11 +1648,11 @@ bool Position::pos_is_ok(int* failedStep) const { // Are the king squares in the position correct? if (failedStep) (*failedStep)++; - if (piece_on(king_square(WHITE)) != WK) + if (piece_on(king_square(WHITE)) != W_KING) return false; if (failedStep) (*failedStep)++; - if (piece_on(king_square(BLACK)) != BK) + if (piece_on(king_square(BLACK)) != B_KING) return false; // Do both sides have exactly one king? @@ -1688,7 +1681,7 @@ bool Position::pos_is_ok(int* failedStep) const { // Is there more than 2 checkers? if (failedStep) (*failedStep)++; - if (debugCheckerCount && count_1s(st->checkersBB) > 2) + if (debugCheckerCount && popcount(st->checkersBB) > 2) return false; // Bitboards OK? @@ -1696,7 +1689,7 @@ bool Position::pos_is_ok(int* failedStep) const { if (debugBitboards) { // The intersection of the white and black pieces must be empty - if ((pieces(WHITE) & pieces(BLACK)) != EmptyBoardBB) + if (!(pieces(WHITE) & pieces(BLACK))) return false; // The union of the white and black pieces must be equal to all @@ -1757,7 +1750,7 @@ bool Position::pos_is_ok(int* failedStep) const { if (debugPieceCounts) for (Color c = WHITE; c <= BLACK; c++) for (PieceType pt = PAWN; pt <= KING; pt++) - if (pieceCount[c][pt] != count_1s(pieces(pt, c))) + if (pieceCount[c][pt] != popcount(pieces(pt, c))) return false; if (failedStep) (*failedStep)++; @@ -1780,7 +1773,7 @@ bool Position::pos_is_ok(int* failedStep) const { if (!can_castle(f)) continue; - Piece rook = (f & (WHITE_OO | WHITE_OOO) ? WR : BR); + Piece rook = (f & (WHITE_OO | WHITE_OOO) ? W_ROOK : B_ROOK); if ( castleRightsMask[castleRookSquare[f]] != (ALL_CASTLES ^ f) || piece_on(castleRookSquare[f]) != rook)