X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=1c9663000e011af6df038d459a1bdb96337a25fa;hp=abde14593bbf833914be4651387e867770262744;hb=9b43fd79372946128924ab3d42c64559e95d29d6;hpb=e7939f450fe5d249bfc9893212dbea1f1829250a diff --git a/src/position.cpp b/src/position.cpp index abde1459..1c966300 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; @@ -223,7 +226,7 @@ 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(); @@ -335,8 +338,8 @@ 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 << '|'; } @@ -349,7 +352,6 @@ void Position::print(Move move) const { /// king) pieces for the given color. Or, when template parameter FindPinned is /// false, the function return the pieces of the given color candidate for a /// discovery check against the enemy king. - template Bitboard Position::hidden_checkers() const { @@ -373,26 +375,12 @@ Bitboard Position::hidden_checkers() const { return result; } +// Explicit template instantiations +template Bitboard Position::hidden_checkers() const; +template Bitboard Position::hidden_checkers() const; -/// Position:pinned_pieces() returns a bitboard of all pinned (against the -/// king) pieces for the side to move. - -Bitboard Position::pinned_pieces() const { - - return hidden_checkers(); -} - - -/// Position:discovered_check_candidates() returns a bitboard containing all -/// pieces for the side to move which are candidates for giving a discovered -/// check. - -Bitboard Position::discovered_check_candidates() const { - - return hidden_checkers(); -} -/// Position::attackers_to() computes a bitboard of all pieces which attacks a +/// Position::attackers_to() computes a bitboard of all pieces which attack a /// given square. Slider attacks use occ bitboard as occupancy. Bitboard Position::attackers_to(Square s, Bitboard occ) const { @@ -405,6 +393,7 @@ Bitboard Position::attackers_to(Square s, Bitboard occ) const { | (attacks_from(s) & pieces(KING)); } + /// Position::attacks_from() computes a bitboard of all attacks of a given piece /// put in a given square. Slider attacks use occ bitboard as occupancy. @@ -412,12 +401,12 @@ 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]; } } @@ -431,22 +420,25 @@ bool Position::move_attacks_square(Move m, Square s) const { assert(square_is_ok(s)); Bitboard occ, xray; - Square f = move_from(m), t = move_to(m); + Square from = from_sq(m); + Square to = to_sq(m); + Piece piece = piece_on(from); + + assert(!square_is_empty(from)); - assert(!square_is_empty(f)); + // Update occupancy as if the piece is moving + occ = occupied_squares(); + do_move_bb(&occ, make_move_bb(from, to)); - if (bit_is_set(attacks_from(piece_on(f), t), s)) + // The piece moved in 'to' attacks the square 's' ? + if (bit_is_set(attacks_from(piece, to, occ), s)) return true; - // Move the piece and scan for X-ray attacks behind it - occ = occupied_squares(); - do_move_bb(&occ, make_move_bb(f, t)); - xray = ( (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN)) - |(bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN))) - & pieces(color_of(piece_on(f))); + // Scan for possible X-ray attackers behind the moved piece + xray = (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN, color_of(piece))) + |(bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN, color_of(piece))); - // If we have attacks we need to verify that are caused by our move - // and are not already existent ones. + // Verify attackers are triggered by our move and not already existing return xray && (xray ^ (xray & attacks_from(s))); } @@ -459,7 +451,7 @@ 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)); @@ -470,7 +462,7 @@ 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(); @@ -478,7 +470,7 @@ 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); @@ -492,19 +484,19 @@ 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)); } /// Position::move_is_legal() takes a random move and tests whether the move -/// is legal. This version is not very fast and should be used only -/// in non time-critical paths. +/// is legal. This version is not very fast and should be used only in non +/// time-critical paths. bool Position::move_is_legal(const Move m) const { @@ -524,8 +516,8 @@ 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 @@ -533,12 +525,12 @@ 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 @@ -621,7 +613,7 @@ 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 @@ -634,7 +626,7 @@ 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; } } @@ -649,10 +641,10 @@ 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_on(from_sq(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 ? @@ -739,7 +731,7 @@ 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 @@ -758,7 +750,7 @@ 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. @@ -767,15 +759,15 @@ 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)); @@ -799,10 +791,10 @@ 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]; @@ -828,7 +820,7 @@ 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 @@ -839,12 +831,12 @@ 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; } @@ -852,13 +844,13 @@ 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); @@ -867,7 +859,7 @@ 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. @@ -882,7 +874,7 @@ 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)) @@ -907,7 +899,7 @@ 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]]; @@ -938,10 +930,10 @@ 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) { @@ -990,8 +982,8 @@ 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; @@ -1032,7 +1024,7 @@ 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. @@ -1050,7 +1042,7 @@ 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 @@ -1085,8 +1077,8 @@ 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 @@ -1128,7 +1120,7 @@ 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; @@ -1142,7 +1134,7 @@ 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); @@ -1236,8 +1228,8 @@ 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 @@ -1264,8 +1256,8 @@ 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(); @@ -1274,7 +1266,7 @@ 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 @@ -1341,7 +1333,7 @@ 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]; } @@ -1367,7 +1359,7 @@ 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; @@ -1513,7 +1505,7 @@ bool Position::is_draw() const { // 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) { @@ -1572,7 +1564,7 @@ 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]); @@ -1666,11 +1658,11 @@ 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? @@ -1699,7 +1691,7 @@ 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? @@ -1707,7 +1699,7 @@ 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 @@ -1768,7 +1760,7 @@ 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)++; @@ -1791,7 +1783,7 @@ 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)