X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=537674c9119c123370c44456cfb7b9ea94301451;hp=f50677bb7e612c8536883ff9037bcecc437d81a1;hb=34178205fc762638e633a61ecc45360e1662bdee;hpb=86e159997cb94926bd91ee3c2f11f761ee69db5b diff --git a/src/position.cpp b/src/position.cpp index f50677bb..537674c9 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -36,7 +36,7 @@ using std::cout; using std::endl; Key Position::zobrist[2][8][64]; -Key Position::zobEp[64]; +Key Position::zobEp[8]; Key Position::zobCastle[16]; Key Position::zobSideToMove; Key Position::zobExclusion; @@ -242,14 +242,27 @@ 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 color and the rook starting square. -void Position::set_castle_right(Color c, Square rsq) { +void Position::set_castle_right(Color c, Square rfrom) { - int f = (rsq < king_square(c) ? WHITE_OOO : WHITE_OO) << c; + Square kfrom = king_square(c); + bool kingSide = kfrom < rfrom; + int cr = (kingSide ? WHITE_OO : WHITE_OOO) << c; - st->castleRights |= f; - castleRightsMask[king_square(c)] ^= f; - castleRightsMask[rsq] ^= f; - castleRookSquare[f] = rsq; + st->castleRights |= cr; + castleRightsMask[kfrom] |= cr; + castleRightsMask[rfrom] |= cr; + castleRookSquare[cr] = rfrom; + + Square kto = relative_square(c, kingSide ? SQ_G1 : SQ_C1); + Square rto = relative_square(c, kingSide ? SQ_F1 : SQ_D1); + + for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); s++) + if (s != kfrom && s != rfrom) + castlePath[cr] |= s; + + for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); s++) + if (s != kfrom && s != rfrom) + castlePath[cr] |= s; } @@ -386,8 +399,8 @@ Bitboard Position::attackers_to(Square s, Bitboard occ) const { return (attacks_from(s, BLACK) & pieces(PAWN, WHITE)) | (attacks_from(s, WHITE) & pieces(PAWN, BLACK)) | (attacks_from(s) & pieces(KNIGHT)) - | (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN)) - | (bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN)) + | (attacks_bb(s, occ) & pieces(ROOK, QUEEN)) + | (attacks_bb(s, occ) & pieces(BISHOP, QUEEN)) | (attacks_from(s) & pieces(KING)); } @@ -401,9 +414,9 @@ Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { switch (type_of(p)) { - 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); + case BISHOP: return attacks_bb(s, occ); + case ROOK : return attacks_bb(s, occ); + case QUEEN : return attacks_bb(s, occ) | attacks_bb(s, occ); default : return StepAttacksBB[p][s]; } } @@ -420,22 +433,20 @@ bool Position::move_attacks_square(Move m, Square s) const { Bitboard occ, xray; Square from = from_sq(m); Square to = to_sq(m); - Piece piece = piece_on(from); + Piece piece = piece_moved(m); assert(!square_is_empty(from)); // Update occupancy as if the piece is moving - occ = occupied_squares(); - occ ^= from; - occ ^= to; + occ = occupied_squares() ^ from ^ to; // The piece moved in 'to' attacks the square 's' ? if (attacks_from(piece, to, occ) & s) return true; // 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))); + xray = (attacks_bb(s, occ) & pieces(ROOK, QUEEN, color_of(piece))) + |(attacks_bb(s, occ) & pieces(BISHOP, QUEEN, color_of(piece))); // Verify attackers are triggered by our move and not already existing return xray && (xray ^ (xray & attacks_from(s))); @@ -452,7 +463,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { Color us = sideToMove; Square from = from_sq(m); - assert(color_of(piece_on(from)) == us); + assert(color_of(piece_moved(m)) == us); assert(piece_on(king_square(us)) == make_piece(us, KING)); // En passant captures are a tricky special case. Because they are rather @@ -464,19 +475,15 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { Square to = to_sq(m); Square capsq = to + pawn_push(them); Square ksq = king_square(us); - Bitboard b = occupied_squares(); + Bitboard b = (occupied_squares() ^ from ^ capsq) | to; assert(to == ep_square()); - assert(piece_on(from) == make_piece(us, PAWN)); + assert(piece_moved(m) == make_piece(us, PAWN)); assert(piece_on(capsq) == make_piece(them, PAWN)); assert(piece_on(to) == NO_PIECE); - b ^= from; - b ^= capsq; - b |= to; - - return !(rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, them)) - && !(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, them)); + return !(attacks_bb(ksq, b) & pieces(ROOK, QUEEN, them)) + && !(attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, them)); } // If the moving piece is a king, check whether the destination @@ -517,14 +524,14 @@ bool Position::is_pseudo_legal(const Move m) const { Color them = ~sideToMove; Square from = from_sq(m); Square to = to_sq(m); - Piece pc = piece_on(from); + Piece pc = piece_moved(m); // Use a slower but simpler function for uncommon cases if (is_special(m)) return move_is_legal(m); // Is not a promotion, so promotion piece must be empty - if (promotion_piece_type(m) - 2 != NO_PIECE_TYPE) + if (promotion_type(m) - 2 != NO_PIECE_TYPE) return false; // If the from square is not occupied by a piece belonging to the side to @@ -606,28 +613,22 @@ bool Position::is_pseudo_legal(const Move m) const { // same kind of moves are filtered out here. if (in_check()) { - // In case of king moves under check we have to remove king so to catch - // as invalid moves like b1a1 when opposite queen is on c1. - if (type_of(piece_on(from)) == KING) + if (type_of(pc) != KING) { - Bitboard b = occupied_squares(); - b ^= from; - if (attackers_to(to_sq(m), b) & pieces(~us)) - return false; - } - else - { - Bitboard target = checkers(); - Square checksq = pop_1st_bit(&target); + Bitboard b = checkers(); + Square checksq = pop_1st_bit(&b); - if (target) // double check ? In this case a king move is required + if (b) // double check ? In this case a king move is required return false; // Our move must be a blocking evasion or a capture of the checking piece - target = squares_between(checksq, king_square(us)) | checkers(); - if (!(target & to_sq(m))) + if (!((squares_between(checksq, king_square(us)) | checkers()) & to)) return false; } + // In case of king moves under check we have to remove king so to catch + // as invalid moves like b1a1 when opposite queen is on c1. + else if (attackers_to(to, occupied_squares() ^ from) & pieces(~us)) + return false; } return true; @@ -664,15 +665,11 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { return false; Color us = sideToMove; - Bitboard b = occupied_squares(); Square ksq = king_square(~us); // Promotion with check ? if (is_promotion(m)) - { - b ^= from; - return attacks_from(Piece(promotion_piece_type(m)), to, b) & ksq; - } + return attacks_from(Piece(promotion_type(m)), to, occupied_squares() ^ from) & ksq; // En passant capture with check ? We have already handled the case // of direct checks and ordinary discovered check, the only case we @@ -681,33 +678,22 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { if (is_enpassant(m)) { Square capsq = make_square(file_of(to), rank_of(from)); - b ^= from; - b ^= capsq; - b |= to; - return (rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, us)) - ||(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us)); + Bitboard b = (occupied_squares() ^ from ^ capsq) | to; + + return (attacks_bb< ROOK>(ksq, b) & pieces( ROOK, QUEEN, us)) + | (attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us)); } // Castling with check ? if (is_castle(m)) { - Square kfrom, kto, rfrom, rto; - kfrom = from; - rfrom = to; + Square kfrom = from; + Square rfrom = to; // 'King captures the rook' notation + Square kto = relative_square(us, rfrom > kfrom ? SQ_G1 : SQ_C1); + Square rto = relative_square(us, rfrom > kfrom ? SQ_F1 : SQ_D1); + Bitboard b = (occupied_squares() ^ kfrom ^ rfrom) | rto | kto; - if (rfrom > kfrom) - { - kto = relative_square(us, SQ_G1); - rto = relative_square(us, SQ_F1); - } else { - kto = relative_square(us, SQ_C1); - rto = relative_square(us, SQ_D1); - } - b ^= kfrom; - b ^= rfrom; - b |= rto; - b |= kto; - return rook_attacks_bb(rto, b) & ksq; + return attacks_bb(rto, b) & ksq; } return false; @@ -835,17 +821,16 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI // Reset en passant square if (st->epSquare != SQ_NONE) { - k ^= zobEp[st->epSquare]; + k ^= zobEp[file_of(st->epSquare)]; st->epSquare = SQ_NONE; } // Update castle rights if needed - if ( st->castleRights != CASTLES_NONE - && (castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES) + if (st->castleRights && (castleRightsMask[from] | castleRightsMask[to])) { - k ^= zobCastle[st->castleRights]; - st->castleRights &= castleRightsMask[from] & castleRightsMask[to]; - k ^= zobCastle[st->castleRights]; + int cr = castleRightsMask[from] | castleRightsMask[to]; + k ^= zobCastle[st->castleRights & cr]; + st->castleRights &= ~cr; } // Prefetch TT access as soon as we know key is updated @@ -869,16 +854,16 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI if (pt == PAWN) { // Set en-passant square, only if moved pawn can be captured - if ( (to ^ from) == 16 + if ( (int(to) ^ int(from)) == 16 && (attacks_from(from + pawn_push(us), us) & pieces(PAWN, them))) { st->epSquare = Square((from + to) / 2); - k ^= zobEp[st->epSquare]; + k ^= zobEp[file_of(st->epSquare)]; } if (is_promotion(m)) { - PieceType promotion = promotion_piece_type(m); + PieceType promotion = promotion_type(m); assert(relative_rank(us, to) == RANK_8); assert(promotion >= KNIGHT && promotion <= QUEEN); @@ -993,7 +978,7 @@ void Position::undo_move(Move m) { if (is_promotion(m)) { - PieceType promotion = promotion_piece_type(m); + PieceType promotion = promotion_type(m); assert(promotion == pt); assert(relative_rank(us, to) == RANK_8); @@ -1146,14 +1131,13 @@ void Position::do_castle_move(Move m) { // Clear en passant square if (st->epSquare != SQ_NONE) { - st->key ^= zobEp[st->epSquare]; + st->key ^= zobEp[file_of(st->epSquare)]; st->epSquare = SQ_NONE; } // Update castling rights - st->key ^= zobCastle[st->castleRights]; - st->castleRights &= castleRightsMask[kfrom]; - st->key ^= zobCastle[st->castleRights]; + st->key ^= zobCastle[st->castleRights & castleRightsMask[kfrom]]; + st->castleRights &= ~castleRightsMask[kfrom]; // Update checkers BB st->checkersBB = attackers_to(king_square(~us)) & pieces(us); @@ -1195,7 +1179,7 @@ void Position::do_null_move(StateInfo& backupSt) { if (Do) { if (st->epSquare != SQ_NONE) - st->key ^= zobEp[st->epSquare]; + st->key ^= zobEp[file_of(st->epSquare)]; st->key ^= zobSideToMove; prefetch((char*)TT.first_entry(st->key)); @@ -1224,13 +1208,10 @@ int Position::see_sign(Move m) const { assert(is_ok(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 // here because king midgame value is set to 0. - if (PieceValueMidgame[piece_on(to)] >= PieceValueMidgame[piece_on(from)]) + if (PieceValueMidgame[piece_on(to_sq(m))] >= PieceValueMidgame[piece_moved(m)]) return 1; return see(m); @@ -1301,8 +1282,8 @@ int Position::see(Move m) const { // and scan for new X-ray attacks behind the attacker. b = stmAttackers & pieces(pt); occ ^= (b & (~b + 1)); - attackers |= (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN)) - | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN)); + attackers |= (attacks_bb(to, occ) & pieces(ROOK, QUEEN)) + | (attacks_bb(to, occ) & pieces(BISHOP, QUEEN)); attackers &= occ; // Cut out pieces we've already done @@ -1340,27 +1321,16 @@ int Position::see(Move m) const { void Position::clear() { + memset(this, 0, sizeof(Position)); + startState.epSquare = SQ_NONE; st = &startState; - memset(st, 0, sizeof(StateInfo)); - st->epSquare = SQ_NONE; - - memset(byColorBB, 0, sizeof(Bitboard) * 2); - memset(byTypeBB, 0, sizeof(Bitboard) * 8); - memset(pieceCount, 0, sizeof(int) * 2 * 8); - memset(index, 0, sizeof(int) * 64); for (int i = 0; i < 8; i++) for (int j = 0; j < 16; j++) pieceList[0][i][j] = pieceList[1][i][j] = SQ_NONE; for (Square sq = SQ_A1; sq <= SQ_H8; sq++) - { board[sq] = NO_PIECE; - castleRightsMask[sq] = ALL_CASTLES; - } - sideToMove = WHITE; - nodes = 0; - occupied = 0; } @@ -1396,7 +1366,7 @@ Key Position::compute_key() const { result ^= zobrist[color_of(piece_on(s))][type_of(piece_on(s))][s]; if (ep_square() != SQ_NONE) - result ^= zobEp[ep_square()]; + result ^= zobEp[file_of(ep_square())]; if (sideToMove == BLACK) result ^= zobSideToMove; @@ -1542,11 +1512,18 @@ void Position::init() { for (Square s = SQ_A1; s <= SQ_H8; s++) zobrist[c][pt][s] = rk.rand(); - for (Square s = SQ_A1; s <= SQ_H8; s++) - zobEp[s] = rk.rand(); + for (File f = FILE_A; f <= FILE_H; f++) + zobEp[f] = rk.rand(); - for (int i = 0; i < 16; i++) - zobCastle[i] = rk.rand(); + for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; cr++) + { + Bitboard b = cr; + while (b) + { + Key k = zobCastle[1 << pop_1st_bit(&b)]; + zobCastle[cr] ^= k ? k : rk.rand(); + } + } zobSideToMove = rk.rand(); zobExclusion = rk.rand(); @@ -1686,7 +1663,7 @@ 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))) + if (pieces(WHITE) & pieces(BLACK)) return false; // The union of the white and black pieces must be equal to all @@ -1772,8 +1749,8 @@ bool Position::pos_is_ok(int* failedStep) const { Piece rook = (f & (WHITE_OO | WHITE_OOO) ? W_ROOK : B_ROOK); - if ( castleRightsMask[castleRookSquare[f]] != (ALL_CASTLES ^ f) - || piece_on(castleRookSquare[f]) != rook) + if ( piece_on(castleRookSquare[f]) != rook + || castleRightsMask[castleRookSquare[f]] != f) return false; }