X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=60c5380d8352e329c2b662e218d75fbb885717cc;hp=98f49c756fe989cee80a1d553889e84dd476aa7c;hb=e56342ed002b2d567fbecd2e4432b881f1b244bc;hpb=67338e6f322b8f8ec0d897815e16a87937efc9b0 diff --git a/src/position.cpp b/src/position.cpp index 98f49c75..60c5380d 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -19,7 +19,6 @@ #include #include -#include #include #include #include @@ -37,7 +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; @@ -67,7 +66,7 @@ const Value PieceValueEndgame[17] = { namespace { // Bonus for having the side to move (modified by Joona Kiiski) - const Score TempoValue = make_score(48, 22); + const Score Tempo = make_score(48, 22); // To convert a Piece to and from a FEN char const string PieceToChar(" PNBRQK pnbrqk ."); @@ -78,8 +77,8 @@ namespace { CheckInfo::CheckInfo(const Position& pos) { - Color them = flip(pos.side_to_move()); - Square ksq = pos.king_square(them); + Color them = ~pos.side_to_move(); + ksq = pos.king_square(them); pinned = pos.pinned_pieces(); dcCandidates = pos.discovered_check_candidates(); @@ -93,33 +92,26 @@ CheckInfo::CheckInfo(const Position& pos) { } -/// Position c'tors. Here we always create a copy of the original position -/// 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::operator=() creates a copy of 'pos'. We want the new born Position +/// object do not depend on any external data so we detach state pointer from +/// the source one. -void Position::copy(const Position& pos, int th) { +void Position::operator=(const Position& pos) { memcpy(this, &pos, sizeof(Position)); startState = *st; st = &startState; - threadID = th; nodes = 0; assert(pos_is_ok()); } -Position::Position(const string& fen, bool isChess960, int th) { - - from_fen(fen, isChess960); - threadID = th; -} - /// Position::from_fen() initializes the position object with the given FEN /// string. This function is not very robust - make sure that input FENs are /// correct (this is assumed to be the responsibility of the GUI). -void Position::from_fen(const string& fenStr, bool isChess960) { +void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { /* A FEN string defines a particular position using only the ASCII character set. @@ -165,11 +157,11 @@ 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) { @@ -192,15 +184,14 @@ 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)); @@ -208,7 +199,7 @@ 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 @@ -231,27 +222,41 @@ void Position::from_fen(const string& fenStr, bool isChess960) { st->key = compute_key(); st->pawnKey = compute_pawn_key(); st->materialKey = compute_material_key(); - st->value = compute_value(); + st->psqScore = compute_psq_score(); st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); st->npMaterial[BLACK] = compute_non_pawn_material(BLACK); - st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(flip(sideToMove)); + st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove); chess960 = isChess960; + thisThread = th; assert(pos_is_ok()); } /// 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(Color c, Square rfrom) { -void Position::set_castle_right(Square ksq, Square rsq) { + Square kfrom = king_square(c); + CastlingSide cs = kfrom < rfrom ? KING_SIDE : QUEEN_SIDE; + int cr = (cs == KING_SIDE ? WHITE_OO : WHITE_OOO) << c; - int f = (rsq < ksq ? WHITE_OOO : WHITE_OO) << color_of(piece_on(ksq)); + st->castleRights |= cr; + castleRightsMask[kfrom] |= cr; + castleRightsMask[rfrom] |= cr; + castleRookSquare[c][cs] = rfrom; - st->castleRights |= f; - castleRightsMask[ksq] ^= f; - castleRightsMask[rsq] ^= f; - castleRookSquare[f] = rsq; + Square kto = relative_square(c, cs == KING_SIDE ? SQ_G1 : SQ_C1); + Square rto = relative_square(c, cs == KING_SIDE ? SQ_F1 : SQ_D1); + + for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); s++) + if (s != kfrom && s != rfrom) + castlePath[c][cs] |= s; + + for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); s++) + if (s != kfrom && s != rfrom) + castlePath[c][cs] |= s; } @@ -272,7 +277,7 @@ const string Position::to_fen() const { { sq = make_square(file, rank); - if (square_is_empty(sq)) + if (square_empty(sq)) emptyCnt++; else { @@ -295,16 +300,16 @@ const string Position::to_fen() const { fen << (sideToMove == WHITE ? " w " : " b "); if (can_castle(WHITE_OO)) - fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE_OO))))) : 'K'); + fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, KING_SIDE))))) : 'K'); if (can_castle(WHITE_OOO)) - fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE_OOO))))) : 'Q'); + fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, QUEEN_SIDE))))) : 'Q'); if (can_castle(BLACK_OO)) - fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK_OO))) : 'k'); + fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, KING_SIDE))) : 'k'); if (can_castle(BLACK_OOO)) - fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK_OOO))) : 'q'); + fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, QUEEN_SIDE))) : 'q'); if (st->castleRights == CASTLES_NONE) fen << '-'; @@ -325,7 +330,7 @@ void Position::print(Move move) const { if (move) { - Position p(*this, thread()); + Position p(*this); cout << "\nMove is: " << (sideToMove == BLACK ? ".." : "") << move_to_san(p, move); } @@ -357,19 +362,18 @@ Bitboard Position::hidden_checkers() const { // Pinned pieces protect our king, dicovery checks attack the enemy king Bitboard b, result = 0; - Bitboard pinners = pieces(FindPinned ? flip(sideToMove) : sideToMove); - Square ksq = king_square(FindPinned ? sideToMove : flip(sideToMove)); + Bitboard pinners = pieces(FindPinned ? ~sideToMove : sideToMove); + Square ksq = king_square(FindPinned ? sideToMove : ~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) { - b = squares_between(ksq, pop_1st_bit(&pinners)) & occupied_squares(); + b = squares_between(ksq, pop_1st_bit(&pinners)) & pieces(); - // Only one bit set and is an our piece? - if (b && !(b & (b - 1)) && (b & pieces(sideToMove))) + if (b && single_bit(b) && (b & pieces(sideToMove))) result |= b; } return result; @@ -388,8 +392,8 @@ 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)); } @@ -399,13 +403,13 @@ Bitboard Position::attackers_to(Square s, Bitboard occ) const { Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { - assert(square_is_ok(s)); + assert(is_ok(s)); 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]; } } @@ -417,26 +421,25 @@ Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { bool Position::move_attacks_square(Move m, Square s) const { assert(is_ok(m)); - assert(square_is_ok(s)); + assert(is_ok(s)); 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)); + assert(!square_empty(from)); // Update occupancy as if the piece is moving - occ = occupied_squares(); - do_move_bb(&occ, make_move_bb(from, to)); + occ = pieces() ^ from ^ to; // The piece moved in 'to' attacks the square 's' ? - if (bit_is_set(attacks_from(piece, to, occ), 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))); @@ -450,10 +453,10 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(is_ok(m)); assert(pinned == pinned_pieces()); - Color us = side_to_move(); + 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 @@ -461,35 +464,31 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { // the move is made. if (is_enpassant(m)) { - Color them = flip(us); + Color them = ~us; Square to = to_sq(m); Square capsq = to + pawn_push(them); Square ksq = king_square(us); - Bitboard b = occupied_squares(); + Bitboard b = (pieces() ^ 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); - clear_bit(&b, from); - clear_bit(&b, capsq); - set_bit(&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 // 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(to_sq(m)) & pieces(flip(us))); + return is_castle(m) || !(attackers_to(to_sq(m)) & pieces(~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) + || !(pinned & from) || squares_aligned(from, to_sq(m), king_square(us)); } @@ -515,17 +514,17 @@ bool Position::move_is_legal(const Move m) const { bool Position::is_pseudo_legal(const Move m) const { Color us = sideToMove; - Color them = flip(sideToMove); + 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 @@ -571,7 +570,7 @@ bool Position::is_pseudo_legal(const Move m) const { case DELTA_N: case DELTA_S: // Pawn push. The destination square must be empty. - if (!square_is_empty(to)) + if (!square_empty(to)) return false; break; @@ -580,8 +579,8 @@ bool Position::is_pseudo_legal(const Move m) const { // rank, and both the destination square and the square between the // source and destination squares must be empty. if ( rank_of(to) != RANK_4 - || !square_is_empty(to) - || !square_is_empty(from + DELTA_N)) + || !square_empty(to) + || !square_empty(from + DELTA_N)) return false; break; @@ -590,8 +589,8 @@ bool Position::is_pseudo_legal(const Move m) const { // rank, and both the destination square and the square between the // source and destination squares must be empty. if ( rank_of(to) != RANK_5 - || !square_is_empty(to) - || !square_is_empty(from + DELTA_S)) + || !square_empty(to) + || !square_empty(from + DELTA_S)) return false; break; @@ -599,7 +598,7 @@ bool Position::is_pseudo_legal(const Move m) const { return false; } } - else if (!bit_is_set(attacks_from(pc, from), to)) + else if (!(attacks_from(pc, from) & to)) return false; // Evasions generator already takes care to avoid some kind of illegal moves @@ -607,28 +606,22 @@ 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) - { - Bitboard b = occupied_squares(); - clear_bit(&b, from); - if (attackers_to(to_sq(m), b) & pieces(flip(us))) - return false; - } - else + if (type_of(pc) != KING) { - 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 (!bit_is_set(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, pieces() ^ from) & pieces(~us)) + return false; } return true; @@ -641,22 +634,22 @@ 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(from_sq(m))) == side_to_move()); + assert(color_of(piece_moved(m)) == sideToMove); Square from = from_sq(m); Square to = to_sq(m); PieceType pt = type_of(piece_on(from)); // Direct check ? - if (bit_is_set(ci.checkSq[pt], to)) + if (ci.checkSq[pt] & to) return true; // Discovery check ? - if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) + if (ci.dcCandidates && (ci.dcCandidates & from)) { // For pawn and king moves we need to verify also direction if ( (pt != PAWN && pt != KING) - || !squares_aligned(from, to, king_square(flip(side_to_move())))) + || !squares_aligned(from, to, king_square(~sideToMove))) return true; } @@ -664,16 +657,12 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { if (!is_special(m)) return false; - Color us = side_to_move(); - Bitboard b = occupied_squares(); - Square ksq = king_square(flip(us)); + Color us = sideToMove; + Square ksq = king_square(~us); // Promotion with check ? if (is_promotion(m)) - { - clear_bit(&b, from); - return bit_is_set(attacks_from(Piece(promotion_piece_type(m)), to, b), ksq); - } + return attacks_from(Piece(promotion_type(m)), to, pieces() ^ from) & ksq; // En passant capture with check ? We have already handled the case // of direct checks and ordinary discovered check, the only case we @@ -682,33 +671,22 @@ 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)); - clear_bit(&b, from); - clear_bit(&b, capsq); - set_bit(&b, to); - return (rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, us)) - ||(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us)); + Bitboard b = (pieces() ^ 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 = (pieces() ^ 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); - } - clear_bit(&b, kfrom); - clear_bit(&b, rfrom); - set_bit(&b, rto); - set_bit(&b, kto); - return bit_is_set(rook_attacks_bb(rto, b), ksq); + return attacks_bb(rto, b) & ksq; } return false; @@ -740,7 +718,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI Key pawnKey, materialKey; Value npMaterial[2]; int castleRights, rule50, pliesFromNull; - Score value; + Score psq_score; Square epSquare; }; @@ -753,7 +731,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI 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. + // case of a capture or a pawn move is taken care of later. st->rule50++; st->pliesFromNull++; @@ -764,8 +742,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI return; } - Color us = side_to_move(); - Color them = flip(us); + Color us = sideToMove; + Color them = ~us; Square from = from_sq(m); Square to = to_sq(m); Piece piece = piece_on(from); @@ -803,9 +781,9 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI st->npMaterial[them] -= PieceValueMidgame[capture]; // Remove the captured piece - clear_bit(&byColorBB[them], capsq); - clear_bit(&byTypeBB[capture], capsq); - clear_bit(&occupied, capsq); + byTypeBB[ALL_PIECES] ^= capsq; + byTypeBB[capture] ^= capsq; + byColorBB[them] ^= capsq; // Update piece list, move the last piece at index[capsq] position and // shrink the list. @@ -824,7 +802,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI st->materialKey ^= zobrist[them][capture][pieceCount[them][capture]]; // Update incremental scores - st->value -= pst(make_piece(them, capture), capsq); + st->psqScore -= pieceSquareTable[make_piece(them, capture)][capsq]; // Reset rule 50 counter st->rule50 = 0; @@ -836,27 +814,26 @@ 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 prefetch((char*)TT.first_entry(k)); // Move the piece - Bitboard move_bb = make_move_bb(from, to); - do_move_bb(&byColorBB[us], move_bb); - do_move_bb(&byTypeBB[pt], move_bb); - do_move_bb(&occupied, move_bb); + Bitboard from_to_bb = SquareBB[from] | SquareBB[to]; + byTypeBB[ALL_PIECES] ^= from_to_bb; + byTypeBB[pt] ^= from_to_bb; + byColorBB[us] ^= from_to_bb; board[to] = board[from]; board[from] = NO_PIECE; @@ -870,23 +847,23 @@ 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); // Replace the pawn with the promoted piece - clear_bit(&byTypeBB[PAWN], to); - set_bit(&byTypeBB[promotion], to); + byTypeBB[PAWN] ^= to; + byTypeBB[promotion] |= to; board[to] = make_piece(us, promotion); // Update piece lists, move the last pawn at index[to] position @@ -905,8 +882,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI ^ zobrist[us][PAWN][pieceCount[us][PAWN]]; // Update incremental score - st->value += pst(make_piece(us, promotion), to) - - pst(make_piece(us, PAWN), to); + st->psqScore += pieceSquareTable[make_piece(us, promotion)][to] + - pieceSquareTable[make_piece(us, PAWN)][to]; // Update material st->npMaterial[us] += PieceValueMidgame[promotion]; @@ -920,11 +897,11 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI } // Prefetch pawn and material hash tables - Threads[threadID].pawnTable.prefetch(st->pawnKey); - Threads[threadID].materialTable.prefetch(st->materialKey); + prefetch((char*)thisThread->pawnTable.entries[st->pawnKey]); + prefetch((char*)thisThread->materialTable.entries[st->materialKey]); // Update incremental scores - st->value += pst_delta(piece, from, to); + st->psqScore += psq_delta(piece, from, to); // Set capture piece st->capturedType = capture; @@ -942,11 +919,11 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI else { // Direct checks - if (bit_is_set(ci.checkSq[pt], to)) - st->checkersBB = SetMaskBB[to]; + if (ci.checkSq[pt] & to) + st->checkersBB |= to; // Discovery checks - if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) + if (ci.dcCandidates && (ci.dcCandidates & from)) { if (pt != ROOK) st->checkersBB |= attacks_from(king_square(them)) & pieces(ROOK, QUEEN, us); @@ -958,8 +935,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI } // Finish - sideToMove = flip(sideToMove); - st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); + sideToMove = ~sideToMove; + st->psqScore += (sideToMove == WHITE ? Tempo : -Tempo); assert(pos_is_ok()); } @@ -972,7 +949,7 @@ void Position::undo_move(Move m) { assert(is_ok(m)); - sideToMove = flip(sideToMove); + sideToMove = ~sideToMove; if (is_castle(m)) { @@ -980,29 +957,29 @@ void Position::undo_move(Move m) { return; } - Color us = side_to_move(); - Color them = flip(us); + Color us = sideToMove; + Color them = ~us; Square from = from_sq(m); Square to = to_sq(m); Piece piece = piece_on(to); PieceType pt = type_of(piece); PieceType capture = st->capturedType; - assert(square_is_empty(from)); + assert(square_empty(from)); assert(color_of(piece) == us); assert(capture != KING); 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); assert(promotion >= KNIGHT && promotion <= QUEEN); // Replace the promoted piece with the pawn - clear_bit(&byTypeBB[promotion], to); - set_bit(&byTypeBB[PAWN], to); + byTypeBB[promotion] ^= to; + byTypeBB[PAWN] |= to; board[to] = make_piece(us, PAWN); // Update piece lists, move the last promoted piece at index[to] position @@ -1018,10 +995,10 @@ void Position::undo_move(Move m) { } // Put the piece back at the source square - Bitboard move_bb = make_move_bb(to, from); - do_move_bb(&byColorBB[us], move_bb); - do_move_bb(&byTypeBB[pt], move_bb); - do_move_bb(&occupied, move_bb); + Bitboard from_to_bb = SquareBB[from] | SquareBB[to]; + byTypeBB[ALL_PIECES] ^= from_to_bb; + byTypeBB[pt] ^= from_to_bb; + byColorBB[us] ^= from_to_bb; board[from] = board[to]; board[to] = NO_PIECE; @@ -1046,9 +1023,9 @@ void Position::undo_move(Move m) { } // Restore the captured piece - set_bit(&byColorBB[them], capsq); - set_bit(&byTypeBB[capture], capsq); - set_bit(&occupied, capsq); + byTypeBB[ALL_PIECES] |= capsq; + byTypeBB[capture] |= capsq; + byColorBB[them] |= capsq; board[capsq] = make_piece(them, capture); @@ -1076,7 +1053,7 @@ void Position::do_castle_move(Move m) { Square kto, kfrom, rfrom, rto, kAfter, rAfter; - Color us = side_to_move(); + Color us = sideToMove; Square kBefore = from_sq(m); Square rBefore = to_sq(m); @@ -1102,20 +1079,20 @@ void Position::do_castle_move(Move m) { assert(piece_on(rfrom) == make_piece(us, ROOK)); // Remove pieces from source squares - clear_bit(&byColorBB[us], kfrom); - clear_bit(&byTypeBB[KING], kfrom); - clear_bit(&occupied, kfrom); - clear_bit(&byColorBB[us], rfrom); - clear_bit(&byTypeBB[ROOK], rfrom); - clear_bit(&occupied, rfrom); + byTypeBB[ALL_PIECES] ^= kfrom; + byTypeBB[KING] ^= kfrom; + byColorBB[us] ^= kfrom; + byTypeBB[ALL_PIECES] ^= rfrom; + byTypeBB[ROOK] ^= rfrom; + byColorBB[us] ^= rfrom; // Put pieces on destination squares - set_bit(&byColorBB[us], kto); - set_bit(&byTypeBB[KING], kto); - set_bit(&occupied, kto); - set_bit(&byColorBB[us], rto); - set_bit(&byTypeBB[ROOK], rto); - set_bit(&occupied, rto); + byTypeBB[ALL_PIECES] |= kto; + byTypeBB[KING] |= kto; + byColorBB[us] |= kto; + byTypeBB[ALL_PIECES] |= rto; + byTypeBB[ROOK] |= rto; + byColorBB[us] |= rto; // Update board Piece king = make_piece(us, KING); @@ -1137,8 +1114,8 @@ void Position::do_castle_move(Move m) { st->capturedType = NO_PIECE_TYPE; // Update incremental scores - st->value += pst_delta(king, kfrom, kto); - st->value += pst_delta(rook, rfrom, rto); + st->psqScore += psq_delta(king, kfrom, kto); + st->psqScore += psq_delta(rook, rfrom, rto); // Update hash key st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto]; @@ -1147,24 +1124,20 @@ 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]; - - // Reset rule 50 counter - st->rule50 = 0; + st->key ^= zobCastle[st->castleRights & castleRightsMask[kfrom]]; + st->castleRights &= ~castleRightsMask[kfrom]; // Update checkers BB - st->checkersBB = attackers_to(king_square(flip(us))) & pieces(us); + st->checkersBB = attackers_to(king_square(~us)) & pieces(us); // Finish - sideToMove = flip(sideToMove); - st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); + sideToMove = ~sideToMove; + st->psqScore += (sideToMove == WHITE ? Tempo : -Tempo); } else // Undo: point our state pointer back to the previous state @@ -1190,16 +1163,16 @@ void Position::do_null_move(StateInfo& backupSt) { dst->key = src->key; dst->epSquare = src->epSquare; - dst->value = src->value; + dst->psqScore = src->psqScore; dst->rule50 = src->rule50; dst->pliesFromNull = src->pliesFromNull; - sideToMove = flip(sideToMove); + sideToMove = ~sideToMove; 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)); @@ -1207,7 +1180,7 @@ void Position::do_null_move(StateInfo& backupSt) { st->epSquare = SQ_NONE; st->rule50++; st->pliesFromNull = 0; - st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue; + st->psqScore += (sideToMove == WHITE ? Tempo : -Tempo); } assert(pos_is_ok()); @@ -1228,13 +1201,10 @@ 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); @@ -1259,28 +1229,28 @@ int Position::see(Move m) const { from = from_sq(m); to = to_sq(m); capturedType = type_of(piece_on(to)); - occ = occupied_squares(); + occ = pieces(); // Handle en passant moves if (is_enpassant(m)) { - Square capQq = to - pawn_push(side_to_move()); + Square capQq = to - pawn_push(sideToMove); - assert(capturedType == NO_PIECE_TYPE); + assert(!capturedType); assert(type_of(piece_on(capQq)) == PAWN); // Remove the captured pawn - clear_bit(&occ, capQq); + occ ^= capQq; capturedType = PAWN; } // Find all attackers to the destination square, with the moving piece // removed, but possibly an X-ray attacker added behind it. - clear_bit(&occ, from); + occ ^= from; attackers = attackers_to(to, occ); // If the opponent has no attackers we are finished - stm = flip(color_of(piece_on(from))); + stm = ~color_of(piece_on(from)); stmAttackers = attackers & pieces(stm); if (!stmAttackers) return PieceValueMidgame[capturedType]; @@ -1305,8 +1275,8 @@ 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 @@ -1318,7 +1288,7 @@ int Position::see(Move m) const { // Remember the value of the capturing piece, and change the side to // move before beginning the next iteration. capturedType = pt; - stm = flip(stm); + stm = ~stm; stmAttackers = attackers & pieces(stm); // Stop before processing a king capture @@ -1344,27 +1314,16 @@ 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; } @@ -1380,9 +1339,9 @@ void Position::put_piece(Piece p, Square s) { index[s] = pieceCount[c][pt]++; pieceList[c][pt][index[s]] = s; - set_bit(&byTypeBB[pt], s); - set_bit(&byColorBB[c], s); - set_bit(&occupied, s); + byTypeBB[ALL_PIECES] |= s; + byTypeBB[pt] |= s; + byColorBB[c] |= s; } @@ -1396,13 +1355,13 @@ Key Position::compute_key() const { Key result = zobCastle[st->castleRights]; for (Square s = SQ_A1; s <= SQ_H8; s++) - if (!square_is_empty(s)) + if (!square_empty(s)) 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 (side_to_move() == BLACK) + if (sideToMove == BLACK) result ^= zobSideToMove; return result; @@ -1449,11 +1408,11 @@ Key Position::compute_material_key() const { } -/// Position::compute_value() compute the incremental scores for the middle +/// Position::compute_psq_score() computes the incremental scores for the middle /// game and the endgame. These functions are used to initialize the incremental /// scores when a new position is set up, and to verify that the scores are correctly /// updated by do_move and undo_move when the program is running in debug mode. -Score Position::compute_value() const { +Score Position::compute_psq_score() const { Bitboard b; Score result = SCORE_ZERO; @@ -1463,10 +1422,10 @@ Score Position::compute_value() const { { b = pieces(pt, c); while (b) - result += pst(make_piece(c, pt), pop_1st_bit(&b)); + result += pieceSquareTable[make_piece(c, pt)][pop_1st_bit(&b)]; } - result += (side_to_move() == WHITE ? TempoValue / 2 : -TempoValue / 2); + result += (sideToMove == WHITE ? Tempo / 2 : -Tempo / 2); return result; } @@ -1499,7 +1458,7 @@ 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? @@ -1531,15 +1490,6 @@ 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 @@ -1555,11 +1505,18 @@ 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[1ULL << pop_1st_bit(&b)]; + zobCastle[cr] ^= k ? k : rk.rand(); + } + } zobSideToMove = rk.rand(); zobExclusion = rk.rand(); @@ -1571,57 +1528,48 @@ void Position::init() { for (Square s = SQ_A1; s <= SQ_H8; s++) { pieceSquareTable[p][s] = ps + PSQT[p][s]; - pieceSquareTable[p+8][flip(s)] = -pieceSquareTable[p][s]; + pieceSquareTable[p+8][~s] = -pieceSquareTable[p][s]; } } } -/// Position::flip_me() flips position with the white and black sides reversed. This +/// Position::flip() flips position with the white and black sides reversed. This /// is only useful for debugging especially for finding evaluation symmetry bugs. -void Position::flip_me() { +void Position::flip() { - // Make a copy of current position before to start changing - const Position pos(*this, threadID); + const Position pos(*this); clear(); - threadID = pos.thread(); - // Board - for (Square s = SQ_A1; s <= SQ_H8; s++) - if (!pos.square_is_empty(s)) - put_piece(Piece(pos.piece_on(s) ^ 8), flip(s)); + sideToMove = ~pos.side_to_move(); + thisThread = pos.this_thread(); + nodes = pos.nodes_searched(); + chess960 = pos.is_chess960(); + startPosPly = pos.startpos_ply_counter(); - // Side to move - sideToMove = flip(pos.side_to_move()); + for (Square s = SQ_A1; s <= SQ_H8; s++) + if (!pos.square_empty(s)) + put_piece(Piece(pos.piece_on(s) ^ 8), ~s); - // 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, ~pos.castle_rook_square(WHITE, KING_SIDE)); if (pos.can_castle(WHITE_OOO)) - set_castle_right(king_square(BLACK), flip(pos.castle_rook_square(WHITE_OOO))); + set_castle_right(BLACK, ~pos.castle_rook_square(WHITE, QUEEN_SIDE)); if (pos.can_castle(BLACK_OO)) - set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OO))); + set_castle_right(WHITE, ~pos.castle_rook_square(BLACK, KING_SIDE)); if (pos.can_castle(BLACK_OOO)) - set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OOO))); + set_castle_right(WHITE, ~pos.castle_rook_square(BLACK, QUEEN_SIDE)); - // En passant square if (pos.st->epSquare != SQ_NONE) - st->epSquare = flip(pos.st->epSquare); - - // Checkers - st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(flip(sideToMove)); + st->epSquare = ~pos.st->epSquare; - // Hash keys st->key = compute_key(); st->pawnKey = compute_pawn_key(); st->materialKey = compute_material_key(); - - // Incremental scores - st->value = compute_value(); - - // Material + st->psqScore = compute_psq_score(); + st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove); st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); st->npMaterial[BLACK] = compute_non_pawn_material(BLACK); @@ -1653,7 +1601,7 @@ bool Position::pos_is_ok(int* failedStep) const { if (failedStep) *failedStep = 1; // Side to move OK? - if (side_to_move() != WHITE && side_to_move() != BLACK) + if (sideToMove != WHITE && sideToMove != BLACK) return false; // Are the king squares in the position correct? @@ -1682,8 +1630,8 @@ bool Position::pos_is_ok(int* failedStep) const { if (failedStep) (*failedStep)++; if (debugKingCapture) { - Color us = side_to_move(); - Color them = flip(us); + Color us = sideToMove; + Color them = ~us; Square ksq = king_square(them); if (attackers_to(ksq) & pieces(us)) return false; @@ -1699,12 +1647,12 @@ 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 // occupied squares - if ((pieces(WHITE) | pieces(BLACK)) != occupied_squares()) + if ((pieces(WHITE) | pieces(BLACK)) != pieces()) return false; // Separate piece type bitboards must have empty intersections @@ -1720,7 +1668,7 @@ bool Position::pos_is_ok(int* failedStep) const { { // The en passant square must be on rank 6, from the point of view of the // side to move. - if (relative_rank(side_to_move(), ep_square()) != RANK_6) + if (relative_rank(sideToMove, ep_square()) != RANK_6) return false; } @@ -1741,7 +1689,7 @@ bool Position::pos_is_ok(int* failedStep) const { // Incremental eval OK? if (failedStep) (*failedStep)++; - if (debugIncrementalEval && st->value != compute_value()) + if (debugIncrementalEval && st->psqScore != compute_psq_score()) return false; // Non-pawn material OK? @@ -1778,17 +1726,18 @@ bool Position::pos_is_ok(int* failedStep) const { if (failedStep) (*failedStep)++; if (debugCastleSquares) - for (CastleRight f = WHITE_OO; f <= BLACK_OOO; f = CastleRight(f << 1)) - { - if (!can_castle(f)) - continue; + for (Color c = WHITE; c <= BLACK; c++) + for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s+1)) + { + CastleRight cr = CastleRight((s == KING_SIDE ? WHITE_OO : WHITE_OOO) << c); - Piece rook = (f & (WHITE_OO | WHITE_OOO) ? W_ROOK : B_ROOK); + if (!can_castle(cr)) + continue; - if ( castleRightsMask[castleRookSquare[f]] != (ALL_CASTLES ^ f) - || piece_on(castleRookSquare[f]) != rook) - return false; - } + if ( piece_on(castleRookSquare[c][s]) != make_piece(c, ROOK) + || castleRightsMask[castleRookSquare[c][s]] != cr) + return false; + } if (failedStep) *failedStep = 0; return true;