X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=7de4ae826c246c0705019f2ccab936ff1afd33d6;hp=b6c0a522e204edb3889e02d26036932d1e7da3d7;hb=bd618941ce6586507a641724646b9fe6b211a1b1;hpb=4626ec2890b140829e9971658ca948005b945fd4 diff --git a/src/position.cpp b/src/position.cpp index b6c0a522..7de4ae82 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -51,17 +51,31 @@ Key Position::zobEp[64]; Key Position::zobCastle[16]; Key Position::zobMaterial[2][8][16]; Key Position::zobSideToMove; +Key Position::zobExclusion; Score Position::PieceSquareTable[16][64]; static bool RequestPending = false; -//// -//// Functions -//// /// Constructors +CheckInfo::CheckInfo(const Position& pos) { + + Color us = pos.side_to_move(); + Color them = opposite_color(us); + + ksq = pos.king_square(them); + dcCandidates = pos.discovered_check_candidates(us); + + checkSq[PAWN] = pos.attacks_from(ksq, them); + checkSq[KNIGHT] = pos.attacks_from(ksq); + checkSq[BISHOP] = pos.attacks_from(ksq); + checkSq[ROOK] = pos.attacks_from(ksq); + checkSq[QUEEN] = checkSq[BISHOP] | checkSq[ROOK]; + checkSq[KING] = EmptyBoardBB; +} + Position::Position(const Position& pos) { copy(pos); } @@ -330,16 +344,15 @@ void Position::copy(const Position& pos) { template Bitboard Position::hidden_checkers(Color c) const { - Bitboard pinners, result = EmptyBoardBB; + Bitboard result = EmptyBoardBB; + Bitboard pinners = pieces_of_color(FindPinned ? opposite_color(c) : c); // Pinned pieces protect our king, dicovery checks attack // the enemy king. Square ksq = king_square(FindPinned ? c : opposite_color(c)); - // Pinners are sliders, not checkers, that give check when - // candidate pinned is removed. - pinners = (pieces(ROOK, QUEEN, FindPinned ? opposite_color(c) : c) & RookPseudoAttacks[ksq]) - | (pieces(BISHOP, QUEEN, FindPinned ? opposite_color(c) : c) & BishopPseudoAttacks[ksq]); + // Pinners are sliders, not checkers, that give check when candidate pinned is removed + pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq]) | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]); if (FindPinned && pinners) pinners &= ~st->checkersBB; @@ -539,162 +552,98 @@ bool Position::pl_move_is_evasion(Move m, Bitboard pinned) const bool Position::move_is_check(Move m) const { - Bitboard dc = discovered_check_candidates(side_to_move()); - return move_is_check(m, dc); + return move_is_check(m, CheckInfo(*this)); } -bool Position::move_is_check(Move m, Bitboard dcCandidates) const { +bool Position::move_is_check(Move m, const CheckInfo& ci) const { assert(is_ok()); assert(move_is_ok(m)); - assert(dcCandidates == discovered_check_candidates(side_to_move())); + assert(ci.dcCandidates == discovered_check_candidates(side_to_move())); + assert(color_of_piece_on(move_from(m)) == side_to_move()); + assert(piece_on(ci.ksq) == piece_of_color_and_type(opposite_color(side_to_move()), KING)); - Color us = side_to_move(); - Color them = opposite_color(us); Square from = move_from(m); Square to = move_to(m); - Square ksq = king_square(them); + PieceType pt = type_of_piece_on(from); - assert(color_of_piece_on(from) == us); - assert(piece_on(ksq) == piece_of_color_and_type(them, KING)); + // Direct check ? + if (bit_is_set(ci.checkSq[pt], to)) + return true; - // Proceed according to the type of the moving piece - switch (type_of_piece_on(from)) + // Discovery check ? + if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) { - case PAWN: - - if (bit_is_set(attacks_from(ksq, them), to)) // Normal check? + // For pawn and king moves we need to verify also direction + if ( (pt != PAWN && pt != KING) + ||(direction_between_squares(from, ci.ksq) != direction_between_squares(to, ci.ksq))) return true; + } - if ( dcCandidates // Discovered check? - && bit_is_set(dcCandidates, from) - && (direction_between_squares(from, ksq) != direction_between_squares(to, ksq))) - return true; - - if (move_is_promotion(m)) // Promotion with check? - { - Bitboard b = occupied_squares(); - clear_bit(&b, from); - - switch (move_promotion_piece(m)) - { - case KNIGHT: - return bit_is_set(attacks_from(to), ksq); - case BISHOP: - return bit_is_set(bishop_attacks_bb(to, b), ksq); - case ROOK: - return bit_is_set(rook_attacks_bb(to, b), ksq); - case QUEEN: - return bit_is_set(queen_attacks_bb(to, b), ksq); - default: - assert(false); - } - } - // En passant capture with check? We have already handled the case - // of direct checks and ordinary discovered check, the only case we - // need to handle is the unusual case of a discovered check through the - // captured pawn. - else if (move_is_ep(m)) - { - Square capsq = make_square(square_file(to), square_rank(from)); - Bitboard b = occupied_squares(); - 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)); - } + // Can we skip the ugly special cases ? + if (!move_is_special(m)) return false; - // Test discovered check and normal check according to piece type - case KNIGHT: - return (dcCandidates && bit_is_set(dcCandidates, from)) - || bit_is_set(attacks_from(ksq), to); - - case BISHOP: - return (dcCandidates && bit_is_set(dcCandidates, from)) - || (direction_is_diagonal(ksq, to) && bit_is_set(attacks_from(ksq), to)); - - case ROOK: - return (dcCandidates && bit_is_set(dcCandidates, from)) - || (direction_is_straight(ksq, to) && bit_is_set(attacks_from(ksq), to)); - - case QUEEN: - // Discovered checks are impossible! - assert(!bit_is_set(dcCandidates, from)); - return ( (direction_is_straight(ksq, to) && bit_is_set(attacks_from(ksq), to)) - || (direction_is_diagonal(ksq, to) && bit_is_set(attacks_from(ksq), to))); - - case KING: - // Discovered check? - if ( bit_is_set(dcCandidates, from) - && (direction_between_squares(from, ksq) != direction_between_squares(to, ksq))) - return true; + Color us = side_to_move(); + Bitboard b = occupied_squares(); - // Castling with check? - if (move_is_castle(m)) - { - Square kfrom, kto, rfrom, rto; - Bitboard b = occupied_squares(); - kfrom = from; - rfrom = to; + // Promotion with check ? + if (move_is_promotion(m)) + { + clear_bit(&b, from); - 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); + switch (move_promotion_piece(m)) + { + case KNIGHT: + return bit_is_set(attacks_from(to), ci.ksq); + case BISHOP: + return bit_is_set(bishop_attacks_bb(to, b), ci.ksq); + case ROOK: + return bit_is_set(rook_attacks_bb(to, b), ci.ksq); + case QUEEN: + return bit_is_set(queen_attacks_bb(to, b), ci.ksq); + default: + assert(false); } - return false; - - default: // NO_PIECE_TYPE - break; } - assert(false); - return false; -} - - -/// Position::update_checkers() udpates chekers info given the move. It is called -/// in do_move() and is faster then find_checkers(). -template -inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, - Square to, Bitboard dcCandidates) { - - const bool Bishop = (Piece == QUEEN || Piece == BISHOP); - const bool Rook = (Piece == QUEEN || Piece == ROOK); - const bool Slider = Bishop || Rook; - - // Direct checks - if ( ( (Bishop && bit_is_set(BishopPseudoAttacks[ksq], to)) - || (Rook && bit_is_set(RookPseudoAttacks[ksq], to))) - && bit_is_set(attacks_from(ksq), to)) // slow, try to early skip - set_bit(pCheckersBB, to); - - else if ( Piece != KING - && !Slider - && bit_is_set(Piece == PAWN ? attacks_from(ksq, opposite_color(sideToMove)) - : attacks_from(ksq), to)) - set_bit(pCheckersBB, to); + // En passant capture with check? We have already handled the case + // of direct checks and ordinary discovered check, the only case we + // need to handle is the unusual case of a discovered check through the + // captured pawn. + if (move_is_ep(m)) + { + Square capsq = make_square(square_file(to), square_rank(from)); + clear_bit(&b, from); + clear_bit(&b, capsq); + set_bit(&b, to); + return (rook_attacks_bb(ci.ksq, b) & pieces(ROOK, QUEEN, us)) + ||(bishop_attacks_bb(ci.ksq, b) & pieces(BISHOP, QUEEN, us)); + } - // Discovery checks - if (Piece != QUEEN && bit_is_set(dcCandidates, from)) + // Castling with check ? + if (move_is_castle(m)) { - if (Piece != ROOK) - (*pCheckersBB) |= (attacks_from(ksq) & pieces(ROOK, QUEEN, side_to_move())); + Square kfrom, kto, rfrom, rto; + kfrom = from; + rfrom = to; - if (Piece != BISHOP) - (*pCheckersBB) |= (attacks_from(ksq) & pieces(BISHOP, QUEEN, side_to_move())); + 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), ci.ksq); } + + return false; } @@ -704,10 +653,11 @@ inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square void Position::do_move(Move m, StateInfo& newSt) { - do_move(m, newSt, discovered_check_candidates(side_to_move())); + CheckInfo ci(*this); + do_move(m, newSt, ci, move_is_check(m, ci)); } -void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { +void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) { assert(is_ok()); assert(move_is_ok(m)); @@ -718,7 +668,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // ones which are recalculated from scratch anyway, then switch our state // pointer to point to the new, ready to be updated, state. struct ReducedStateInfo { - Key key, pawnKey, materialKey; + Key pawnKey, materialKey; int castleRights, rule50, pliesFromNull; Square epSquare; Value value; @@ -758,16 +708,15 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { Piece piece = piece_on(from); PieceType pt = type_of_piece(piece); + PieceType capture = ep ? PAWN : type_of_piece_on(to); assert(color_of_piece_on(from) == us); assert(color_of_piece_on(to) == them || square_is_empty(to)); assert(!(ep || pm) || piece == piece_of_color_and_type(us, PAWN)); assert(!pm || relative_rank(us, to) == RANK_8); - st->capture = ep ? PAWN : type_of_piece_on(to); - - if (st->capture) - do_capture_move(key, st->capture, them, to, ep); + if (capture) + do_capture_move(key, capture, them, to, ep); // Update hash key key ^= zobrist[us][pt][from] ^ zobrist[us][pt][to]; @@ -817,7 +766,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; // Set en passant square, only if moved pawn can be captured - if (abs(int(to) - int(from)) == 16) + if ((to ^ from) == 16) { if (attacks_from(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them)) { @@ -830,6 +779,9 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // Update incremental scores st->value += pst_delta(piece, from, to); + // Set capture piece + st->capture = capture; + if (pm) // promotion ? { PieceType promotion = move_promotion_piece(m); @@ -874,27 +826,33 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { st->key = key; // Update checkers bitboard, piece must be already moved - if (ep | pm) - st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); - else + st->checkersBB = EmptyBoardBB; + + if (moveIsCheck) { - st->checkersBB = EmptyBoardBB; - Square ksq = king_square(them); - switch (pt) + if (ep | pm) + st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); + else { - case PAWN: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - case KNIGHT: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - case BISHOP: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - case ROOK: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - case QUEEN: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - case KING: update_checkers(&(st->checkersBB), ksq, from, to, dcCandidates); break; - default: assert(false); break; + // Direct checks + if (bit_is_set(ci.checkSq[pt], to)) + st->checkersBB = SetMaskBB[to]; + + // Discovery checks + if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) + { + if (pt != ROOK) + st->checkersBB |= (attacks_from(ci.ksq) & pieces(ROOK, QUEEN, us)); + + if (pt != BISHOP) + st->checkersBB |= (attacks_from(ci.ksq) & pieces(BISHOP, QUEEN, us)); + } } } // Finish sideToMove = opposite_color(sideToMove); - st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue; + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); } @@ -1054,7 +1012,7 @@ void Position::do_castle_move(Move m) { // Finish sideToMove = opposite_color(sideToMove); - st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue; + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); } @@ -1631,7 +1589,7 @@ Key Position::compute_material_key() const { /// updated by do_move and undo_move when the program is running in debug mode. Score Position::compute_value() const { - Score result(0, 0); + Score result = make_score(0, 0); Bitboard b; Square s; @@ -1647,7 +1605,7 @@ Score Position::compute_value() const { } } - result += (side_to_move() == WHITE)? TempoValue / 2 : -TempoValue / 2; + result += (side_to_move() == WHITE ? TempoValue / 2 : -TempoValue / 2); return result; } @@ -1779,6 +1737,8 @@ void Position::init_zobrist() { for (int i = 0; i < 16; i++) zobMaterial[0][KING][i] = zobMaterial[1][KING][i] = Key(0ULL); + + zobExclusion = genrand_int64(); } @@ -1796,7 +1756,7 @@ void Position::init_piece_square_tables() { for (Piece p = WP; p <= WK; p++) { i = (r == 0)? 0 : (genrand_int32() % (r*2) - r); - PieceSquareTable[p][s] = Score(MgPST[p][s] + i, EgPST[p][s] + i); + PieceSquareTable[p][s] = make_score(MgPST[p][s] + i, EgPST[p][s] + i); } for (Square s = SQ_A1; s <= SQ_H8; s++)