X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=00e1adf5caa293bcff46b0b263f55196319d2fb7;hp=551c4c0e84090006e047916fbf74ce24703b923e;hb=23de3e16f153f91601e0a6a19b793c54a1ba35cd;hpb=049139d025b26a9fbc9cf87f51b578a4fab447cf diff --git a/src/movegen.cpp b/src/movegen.cpp index 551c4c0e..00e1adf5 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -47,84 +47,61 @@ namespace { enum MoveType { CAPTURE, - NON_CAPTURE + NON_CAPTURE, + CHECK, + EVASION }; - // Functions - bool castling_is_check(const Position&, CastlingSide); - // Helper templates template - MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist); - - template - MoveStack* generate_pawn_blocking_evasions(const Position&, Bitboard, Bitboard, MoveStack*); + MoveStack* generate_castle_moves(const Position&, MoveStack*); - template - MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist); + template + MoveStack* generate_pawn_moves(const Position&, MoveStack*, Bitboard = EmptyBoardBB, + Square = SQ_NONE, Bitboard = EmptyBoardBB); - template - MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool promotion); + // Template generate_piece_moves (captures and non-captures) with specializations and overloads + template + MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); - template - MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist); + template<> + MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); - template - MoveStack* generate_pawn_checks(const Position&, Bitboard, Square, MoveStack*); + template + inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us) { - template - inline Bitboard move_pawns(Bitboard p) { + assert(Piece == PAWN); + assert(Type == CAPTURE || Type == NON_CAPTURE); - if (Direction == DELTA_N) - return Us == WHITE ? p << 8 : p >> 8; - else if (Direction == DELTA_NE) - return Us == WHITE ? p << 9 : p >> 7; - else if (Direction == DELTA_NW) - return Us == WHITE ? p << 7 : p >> 9; - else - return p; + return (us == WHITE ? generate_pawn_moves(p, m) + : generate_pawn_moves(p, m)); } - // Template generate_piece_checks() with specializations - template - MoveStack* generate_piece_checks(const Position&, MoveStack*, Color, Bitboard, Square); + // Templates for non-capture checks generation - template<> - inline MoveStack* generate_piece_checks(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) { - - return (us == WHITE ? generate_pawn_checks(p, dc, ksq, m) - : generate_pawn_checks(p, dc, ksq, m)); - } + template + MoveStack* generate_discovered_checks(const Position& pos, Square from, MoveStack* mlist); - // Template generate_piece_moves() with specializations and overloads template - MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard); + MoveStack* generate_direct_checks(const Position&, MoveStack*, Color, Bitboard, Square); template<> - MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); - - template - inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us) { - - assert(Piece == PAWN); + inline MoveStack* generate_direct_checks(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) { - if (Type == CAPTURE) - return (us == WHITE ? generate_pawn_captures(p, m) - : generate_pawn_captures(p, m)); - else - return (us == WHITE ? generate_pawn_noncaptures(p, m) - : generate_pawn_noncaptures(p, m)); + return (us == WHITE ? generate_pawn_moves(p, m, dc, ksq) + : generate_pawn_moves(p, m, dc, ksq)); } + // Template generate_piece_evasions with specializations template - MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard, Bitboard); + MoveStack* generate_piece_evasions(const Position&, MoveStack*, Color, Bitboard, Bitboard); template<> - inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, - Color us, Bitboard t, Bitboard pnd) { + inline MoveStack* generate_piece_evasions(const Position& p, MoveStack* m, + Color us, Bitboard t, Bitboard pnd) { - return (us == WHITE ? generate_pawn_blocking_evasions(p, pnd, t, m) - : generate_pawn_blocking_evasions(p, pnd, t, m)); + return (us == WHITE ? generate_pawn_moves(p, m, pnd, SQ_NONE, t) + : generate_pawn_moves(p, m, pnd, SQ_NONE, t)); } } @@ -134,7 +111,7 @@ namespace { //// -/// generate_captures generates() all pseudo-legal captures and queen +/// generate_captures() generates all pseudo-legal captures and queen /// promotions. Returns a pointer to the end of the move list. MoveStack* generate_captures(const Position& pos, MoveStack* mlist) { @@ -176,8 +153,8 @@ MoveStack* generate_noncaptures(const Position& pos, MoveStack* mlist) { } -/// generate_non_capture_checks() generates all pseudo-legal non-capturing, -/// non-promoting checks. Returns a pointer to the end of the move list. +/// generate_non_capture_checks() generates all pseudo-legal non-captures and +/// underpromotions that give check. Returns a pointer to the end of the move list. MoveStack* generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { @@ -189,26 +166,28 @@ MoveStack* generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bi assert(pos.piece_on(ksq) == piece_of_color_and_type(opposite_color(us), KING)); - // Pieces moves - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - - // Castling moves that give check. Very rare but nice to have! - if ( pos.can_castle_queenside(us) - && (square_rank(ksq) == square_rank(pos.king_square(us)) || square_file(ksq) == FILE_D) - && castling_is_check(pos, QUEEN_SIDE)) - mlist = generate_castle_moves(pos, mlist); - - if ( pos.can_castle_kingside(us) - && (square_rank(ksq) == square_rank(pos.king_square(us)) || square_file(ksq) == FILE_F) - && castling_is_check(pos, KING_SIDE)) - mlist = generate_castle_moves(pos, mlist); + // Discovered non-capture checks + Bitboard b = dc; + while (b) + { + Square from = pop_1st_bit(&b); + switch (pos.type_of_piece_on(from)) + { + case PAWN: /* Will be generated togheter with pawns direct checks */ break; + case KNIGHT: mlist = generate_discovered_checks(pos, from, mlist); break; + case BISHOP: mlist = generate_discovered_checks(pos, from, mlist); break; + case ROOK: mlist = generate_discovered_checks(pos, from, mlist); break; + case KING: mlist = generate_discovered_checks(pos, from, mlist); break; + default: assert(false); break; + } + } - return mlist; + // Direct non-capture checks + mlist = generate_direct_checks(pos, mlist, us, dc, ksq); + mlist = generate_direct_checks(pos, mlist, us, dc, ksq); + mlist = generate_direct_checks(pos, mlist, us, dc, ksq); + mlist = generate_direct_checks(pos, mlist, us, dc, ksq); + return generate_direct_checks(pos, mlist, us, dc, ksq); } @@ -225,6 +204,8 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin Color us = pos.side_to_move(); Color them = opposite_color(us); Square ksq = pos.king_square(us); + Bitboard sliderAttacks = EmptyBoardBB; + Bitboard checkers = pos.checkers(); assert(pos.piece_on(ksq) == piece_of_color_and_type(us, KING)); @@ -232,34 +213,33 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin Bitboard b_noKing = pos.occupied_squares(); clear_bit(&b_noKing, ksq); - // Find squares attacked by slider checkers, we will - // remove them from king evasions set so to avoid a couple + // Find squares attacked by slider checkers, we will remove + // them from the king evasions set so to avoid a couple // of cycles in the slow king evasions legality check loop - // and to be able to use attacks_to(). - Bitboard checkers = pos.checkers(); - Bitboard checkersAttacks = EmptyBoardBB; + // and to be able to use attackers_to(). Bitboard b = checkers & pos.pieces(BISHOP, QUEEN); while (b) { from = pop_1st_bit(&b); - checkersAttacks |= bishop_attacks_bb(from, b_noKing); + sliderAttacks |= bishop_attacks_bb(from, b_noKing); } b = checkers & pos.pieces(ROOK, QUEEN); while (b) { from = pop_1st_bit(&b); - checkersAttacks |= rook_attacks_bb(from, b_noKing); + sliderAttacks |= rook_attacks_bb(from, b_noKing); } - // Generate evasions for king - Bitboard b1 = pos.piece_attacks(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks; + // Generate evasions for king, capture and non capture moves + Bitboard enemy = pos.pieces_of_color(them); + Bitboard b1 = pos.attacks_from(ksq) & ~pos.pieces_of_color(us) & ~sliderAttacks; while (b1) { + // Note that we can use attackers_to() only because we have already + // removed from b1 the squares attacked by slider checkers. to = pop_1st_bit(&b1); - // Note that we can use attacks_to() only because we - // have already removed slider checkers. - if (!pos.attacks_to(to, them)) + if (!(pos.attackers_to(to) & enemy)) (*mlist++).move = make_move(ksq, to); } @@ -275,7 +255,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin // Generate captures of the checking piece // Pawn captures - b1 = pos.pawn_attacks(checksq, them) & pos.pieces(PAWN, us) & ~pinned; + b1 = pos.attacks_from(checksq, them) & pos.pieces(PAWN, us) & ~pinned; while (b1) { from = pop_1st_bit(&b1); @@ -290,9 +270,9 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin } // Pieces captures - b1 = ( (pos.piece_attacks(checksq) & pos.pieces(KNIGHT, us)) - | (pos.piece_attacks(checksq) & pos.pieces(BISHOP, QUEEN, us)) - | (pos.piece_attacks(checksq) & pos.pieces(ROOK, QUEEN, us)) ) & ~pinned; + b1 = ( (pos.attacks_from(checksq) & pos.pieces(KNIGHT, us)) + | (pos.attacks_from(checksq) & pos.pieces(BISHOP, QUEEN, us)) + | (pos.attacks_from(checksq) & pos.pieces(ROOK, QUEEN, us)) ) & ~pinned; while (b1) { @@ -300,21 +280,20 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin (*mlist++).move = make_move(from, checksq); } - // Blocking check evasions are possible only if the checking piece is - // a slider. - if (checkers & (pos.pieces(BISHOP) | pos.pieces(ROOK) | pos.pieces(QUEEN))) + // Blocking check evasions are possible only if the checking piece is a slider + if (sliderAttacks) { Bitboard blockSquares = squares_between(checksq, ksq); assert((pos.occupied_squares() & blockSquares) == EmptyBoardBB); - if (blockSquares != EmptyBoardBB) + if (blockSquares) { - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_evasions(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_evasions(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_evasions(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_evasions(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_evasions(pos, mlist, us, blockSquares, pinned); } } @@ -326,7 +305,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin if (pos.ep_square() != SQ_NONE && (checkers & pos.pieces(PAWN, them))) { to = pos.ep_square(); - b1 = pos.pawn_attacks(to, them) & pos.pieces(PAWN, us); + b1 = pos.attacks_from(to, them) & pos.pieces(PAWN, us); // The checking pawn cannot be a discovered (bishop) check candidate // otherwise we were in check also before last double push move. @@ -348,13 +327,11 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin } -/// generate_legal_moves() computes a complete list of legal moves in the -/// current position. This function is not very fast, and should be used -/// only in situations where performance is unimportant. It wouldn't be -/// very hard to write an efficient legal move generator, but for the moment -/// we don't need it. +/// generate_moves() computes a complete list of legal or pseudo-legal moves in +/// the current position. This function is not very fast, and should be used +/// only in non time-critical paths. -MoveStack* generate_legal_moves(const Position& pos, MoveStack* mlist) { +MoveStack* generate_moves(const Position& pos, MoveStack* mlist, bool pseudoLegal) { assert(pos.is_ok()); @@ -366,6 +343,8 @@ MoveStack* generate_legal_moves(const Position& pos, MoveStack* mlist) { // Generate pseudo-legal moves MoveStack* last = generate_captures(pos, mlist); last = generate_noncaptures(pos, last); + if (pseudoLegal) + return last; // Remove illegal moves from the list for (MoveStack* cur = mlist; cur != last; cur++) @@ -379,10 +358,24 @@ MoveStack* generate_legal_moves(const Position& pos, MoveStack* mlist) { /// move_is_legal() takes a position and a (not necessarily pseudo-legal) -/// move and a pinned pieces bitboard as input, and tests whether -/// the move is legal. If the move is legal, the move itself is -/// returned. If not, the function returns false. This function must -/// only be used when the side to move is not in check. +/// move and tests whether the move is legal. This version is not very fast +/// and should be used only in non time-critical paths. + +bool move_is_legal(const Position& pos, const Move m) { + + MoveStack mlist[256]; + MoveStack* last = generate_moves(pos, mlist, true); + for (MoveStack* cur = mlist; cur != last; cur++) + if (cur->move == m) + return pos.pl_move_is_legal(m); + + return false; +} + + +/// Fast version of move_is_legal() that takes a position a move and a +/// bitboard of pinned pieces as input, and tests whether the move is legal. +/// This version must only be used when the side to move is not in check. bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { @@ -391,8 +384,14 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { assert(move_is_ok(m)); assert(pinned == pos.pinned_pieces(pos.side_to_move())); + // Use a slower but simpler function for uncommon cases + if (move_is_ep(m) || move_is_castle(m)) + return move_is_legal(pos, m); + Color us = pos.side_to_move(); + Color them = opposite_color(us); Square from = move_from(m); + Square to = move_to(m); Piece pc = pos.piece_on(from); // If the from square is not occupied by a piece belonging to the side to @@ -400,100 +399,11 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { if (color_of_piece(pc) != us) return false; - Color them = opposite_color(us); - Square to = move_to(m); - - // En passant moves - if (move_is_ep(m)) - { - // The piece must be a pawn and destination square must be the - // en passant square. - if ( type_of_piece(pc) != PAWN - || to != pos.ep_square()) - return false; - - assert(pos.square_is_empty(to)); - assert(pos.piece_on(to - pawn_push(us)) == piece_of_color_and_type(them, PAWN)); - - // The move is pseudo-legal, check if it is also legal - return pos.pl_move_is_legal(m, pinned); - } - - // Castling moves - if (move_is_short_castle(m)) - { - // The piece must be a king and side to move must still have - // the right to castle kingside. - if ( type_of_piece(pc) != KING - ||!pos.can_castle_kingside(us)) - return false; - - assert(from == pos.king_square(us)); - assert(to == pos.initial_kr_square(us)); - assert(pos.piece_on(to) == piece_of_color_and_type(us, ROOK)); - - Square g1 = relative_square(us, SQ_G1); - Square f1 = relative_square(us, SQ_F1); - Square s; - bool illegal = false; - - // Check if any of the squares between king and rook - // is occupied or under attack. - for (s = Min(from, g1); s <= Max(from, g1); s++) - if ( (s != from && s != to && !pos.square_is_empty(s)) - || pos.attacks_to(s, them)) - illegal = true; - - // Check if any of the squares between king and rook - // is occupied. - for (s = Min(to, f1); s <= Max(to, f1); s++) - if (s != from && s != to && !pos.square_is_empty(s)) - illegal = true; - - return !illegal; - } - - if (move_is_long_castle(m)) - { - // The piece must be a king and side to move must still have - // the right to castle kingside. - if ( type_of_piece(pc) != KING - ||!pos.can_castle_queenside(us)) - return false; - - assert(from == pos.king_square(us)); - assert(to == pos.initial_qr_square(us)); - assert(pos.piece_on(to) == piece_of_color_and_type(us, ROOK)); - - Square c1 = relative_square(us, SQ_C1); - Square d1 = relative_square(us, SQ_D1); - Square s; - bool illegal = false; - - for (s = Min(from, c1); s <= Max(from, c1); s++) - if( (s != from && s != to && !pos.square_is_empty(s)) - || pos.attacks_to(s, them)) - illegal = true; - - for (s = Min(to, d1); s <= Max(to, d1); s++) - if(s != from && s != to && !pos.square_is_empty(s)) - illegal = true; - - if ( square_file(to) == FILE_B - && ( pos.piece_on(to + DELTA_W) == piece_of_color_and_type(them, ROOK) - || pos.piece_on(to + DELTA_W) == piece_of_color_and_type(them, QUEEN))) - illegal = true; - - return !illegal; - } - - // Normal moves - // The destination square cannot be occupied by a friendly piece if (pos.color_of_piece_on(to) == us) return false; - // Proceed according to the type of the moving piece. + // Handle the special case of a pawn move if (type_of_piece(pc) == PAWN) { // Move direction must be compatible with pawn color @@ -501,15 +411,14 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { if ((us == WHITE) != (direction > 0)) return false; - // If the destination square is on the 8/1th rank, the move must - // be a promotion. - if ( ( (square_rank(to) == RANK_8 && us == WHITE) - ||(square_rank(to) == RANK_1 && us != WHITE)) - && !move_is_promotion(m)) + // A pawn move is a promotion iff the destination square is + // on the 8/1th rank. + if (( (square_rank(to) == RANK_8 && us == WHITE) + ||(square_rank(to) == RANK_1 && us != WHITE)) != bool(move_is_promotion(m))) return false; - // Proceed according to the square delta between the source and - // destionation squares. + // Proceed according to the square delta between the origin and + // destination squares. switch (direction) { case DELTA_NW: @@ -557,36 +466,12 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { } // Luckly we can handle all the other pieces in one go - return ( pos.piece_attacks_square(pos.piece_on(from), from, to) + return ( bit_is_set(pos.attacks_from(pc, from), to) && pos.pl_move_is_legal(m, pinned) && !move_is_promotion(m)); } -/// Another version of move_is_legal(), which takes only a position and a move -/// as input. This function does not require that the side to move is not in -/// check. It is not optimized for speed, and is only used for verifying move -/// legality when building a PV from the transposition table. - -bool move_is_legal(const Position& pos, const Move m) { - - Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); - if (!pos.is_check()) - return move_is_legal(pos, m, pinned); - else - { - Position p(pos); - MoveStack mlist[64]; - MoveStack* last = generate_evasions(p, mlist, pinned); - for (MoveStack* cur = mlist; cur != last; cur++) - if (cur->move == m) - return true; - - return false; - } -} - - namespace { template @@ -594,47 +479,60 @@ namespace { Square from; Bitboard b; + const Square* ptr = pos.piece_list_begin(us, Piece); - for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++) + while ((from = *ptr++) != SQ_NONE) { - from = pos.piece_list(us, Piece, i); - b = pos.piece_attacks(from) & target; + b = pos.attacks_from(from) & target; SERIALIZE_MOVES(b); } return mlist; } + template<> + MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { + + Bitboard b; + Square from = pos.king_square(us); + + b = pos.attacks_from(from) & target; + SERIALIZE_MOVES(b); + return mlist; + } + template - MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, - Color us, Bitboard target, Bitboard pinned) { + MoveStack* generate_piece_evasions(const Position& pos, MoveStack* mlist, + Color us, Bitboard target, Bitboard pinned) { Square from; Bitboard b; + const Square* ptr = pos.piece_list_begin(us, Piece); - for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++) + while ((from = *ptr++) != SQ_NONE) { - from = pos.piece_list(us, Piece, i); if (pinned && bit_is_set(pinned, from)) continue; - b = pos.piece_attacks(from) & target; + b = pos.attacks_from(from) & target; SERIALIZE_MOVES(b); } return mlist; } - template<> - MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { - - Bitboard b; - Square from = pos.king_square(us); + template + inline Bitboard move_pawns(Bitboard p) { - b = pos.piece_attacks(from) & target; - SERIALIZE_MOVES(b); - return mlist; + if (Direction == DELTA_N) + return Us == WHITE ? p << 8 : p >> 8; + else if (Direction == DELTA_NE) + return Us == WHITE ? p << 9 : p >> 7; + else if (Direction == DELTA_NW) + return Us == WHITE ? p << 7 : p >> 9; + else + return p; } template - MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool promotion) { + MoveStack* generate_pawn_diagonal_captures(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool promotion) { // Calculate our parametrized parameters at compile time const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); @@ -665,256 +563,169 @@ namespace { return mlist; } - template - MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) { + template + MoveStack* generate_pawn_moves(const Position& pos, MoveStack* mlist, Bitboard dcp, + Square ksq, Bitboard blockSquares) { // Calculate our parametrized parameters at compile time const Color Them = (Us == WHITE ? BLACK : WHITE); const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE); + const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW); const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); + Bitboard b1, b2, dcPawns1, dcPawns2; Square to; - Bitboard pawns = pos.pieces(PAWN, Us); - Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); - bool possiblePromotion = (pawns & TRank7BB); + Bitboard pawns = (Type == EVASION ? pos.pieces(PAWN, Us) & ~dcp : pos.pieces(PAWN, Us)); + bool possiblePromotion = pawns & TRank7BB; - // Standard captures and capturing promotions in both directions - mlist = generate_pawn_captures_diagonal(mlist, pawns, enemyPieces, possiblePromotion); - mlist = generate_pawn_captures_diagonal(mlist, pawns, enemyPieces, possiblePromotion); + if (Type == CAPTURE) + { + // Standard captures and capturing promotions in both directions + Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); + mlist = generate_pawn_diagonal_captures(mlist, pawns, enemyPieces, possiblePromotion); + mlist = generate_pawn_diagonal_captures(mlist, pawns, enemyPieces, possiblePromotion); + } - // Non-capturing promotions if (possiblePromotion) { - Bitboard b1 = move_pawns(pawns) & pos.empty_squares() & TRank8BB; - while (b1) + // When generating checks consider under-promotion moves (both captures + // and non captures) only if can give a discovery check. Note that dcp + // is dc bitboard or pinned bitboard when Type == EVASION. + Bitboard pp = (Type == CHECK ? pawns & dcp : pawns); + + if (Type != EVASION && Type != CAPTURE) { - to = pop_1st_bit(&b1); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN); + Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); + + // Underpromotion captures in the a1-h8 (a8-h1 for black) direction + b1 = move_pawns(pp) & ~FileABB & enemyPieces & TRank8BB; + while (b1) + { + to = pop_1st_bit(&b1); + (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, ROOK); + (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, BISHOP); + (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, KNIGHT); + } + + // Underpromotion captures in the h1-a8 (h8-a1 for black) direction + b1 = move_pawns(pp) & ~FileHBB & enemyPieces & TRank8BB; + while (b1) + { + to = pop_1st_bit(&b1); + (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, ROOK); + (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, BISHOP); + (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, KNIGHT); + } } - } - // En passant captures - if (pos.ep_square() != SQ_NONE) - { - assert(Us != WHITE || square_rank(pos.ep_square()) == RANK_6); - assert(Us != BLACK || square_rank(pos.ep_square()) == RANK_3); - - Bitboard b1 = pawns & pos.pawn_attacks(pos.ep_square(), Them); - assert(b1 != EmptyBoardBB); + // Underpromotion pawn pushes. Also queen promotions for evasions and captures. + b1 = move_pawns(pp) & TRank8BB; + b1 &= (Type == EVASION ? blockSquares : pos.empty_squares()); while (b1) { to = pop_1st_bit(&b1); - (*mlist++).move = make_ep_move(to, pos.ep_square()); + if (Type == EVASION || Type == CAPTURE) + (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN); + + if (Type != CAPTURE) + { + (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK); + (*mlist++).move = make_promotion_move(to - TDELTA_N, to, BISHOP); + (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT); + } } } - return mlist; - } - - template - MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist) { - - // Calculate our parametrized parameters at compile time - const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); - const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); - const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE); - const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW); - const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); - Bitboard b1, b2; - Square to; - Bitboard pawns = pos.pieces(PAWN, Us); - Bitboard emptySquares = pos.empty_squares(); - - if (pawns & TRank7BB) // There is some promotion candidate ? + if (Type != CAPTURE) { - Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); - - // Underpromotion captures in the a1-h8 (a8-h1 for black) direction - b1 = move_pawns(pawns) & ~FileABB & enemyPieces & TRank8BB; - while (b1) + Bitboard emptySquares = pos.empty_squares(); + dcPawns1 = dcPawns2 = EmptyBoardBB; + if (Type == CHECK && (pawns & dcp)) { - to = pop_1st_bit(&b1); - (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, ROOK); - (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, BISHOP); - (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, KNIGHT); + // Pawn moves which gives discovered check. This is possible only if the + // pawn is not on the same file as the enemy king, because we don't + // generate captures. + dcPawns1 = move_pawns(pawns & dcp & ~file_bb(ksq)) & emptySquares & ~TRank8BB; + dcPawns2 = move_pawns(dcPawns1 & TRank3BB) & emptySquares; } - // Underpromotion captures in the h1-a8 (h8-a1 for black) direction - b1 = move_pawns(pawns) & ~FileHBB & enemyPieces & TRank8BB; - while (b1) - { - to = pop_1st_bit(&b1); - (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, ROOK); - (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, BISHOP); - (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, KNIGHT); - } + // Single pawn pushes + b1 = move_pawns(pawns) & emptySquares & ~TRank8BB; + b2 = (Type == CHECK ? (b1 & pos.attacks_from(ksq, Them)) | dcPawns1 : + (Type == EVASION ? b1 & blockSquares : b1)); + SERIALIZE_MOVES_D(b2, -TDELTA_N); + + // Double pawn pushes + b1 = move_pawns(b1 & TRank3BB) & emptySquares; + b2 = (Type == CHECK ? (b1 & pos.attacks_from(ksq, Them)) | dcPawns2 : + (Type == EVASION ? b1 & blockSquares : b1)); + SERIALIZE_MOVES_D(b2, -TDELTA_N -TDELTA_N); + } + else if (pos.ep_square() != SQ_NONE) // En passant captures + { + assert(Us != WHITE || square_rank(pos.ep_square()) == RANK_6); + assert(Us != BLACK || square_rank(pos.ep_square()) == RANK_3); + + b1 = pawns & pos.attacks_from(pos.ep_square(), Them); + assert(b1 != EmptyBoardBB); - // Underpromotion pawn pushes - b1 = move_pawns(pawns) & emptySquares & TRank8BB; while (b1) { to = pop_1st_bit(&b1); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, BISHOP); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT); + (*mlist++).move = make_ep_move(to, pos.ep_square()); } } - - // Single pawn pushes - b2 = b1 = move_pawns(pawns) & emptySquares & ~TRank8BB; - SERIALIZE_MOVES_D(b2, -TDELTA_N); - - // Double pawn pushes - b2 = move_pawns(b1 & TRank3BB) & emptySquares; - SERIALIZE_MOVES_D(b2, -TDELTA_N -TDELTA_N); return mlist; } + template + MoveStack* generate_discovered_checks(const Position& pos, Square from, MoveStack* mlist) { - template - MoveStack* generate_pawn_checks(const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist) - { - // Calculate our parametrized parameters at compile time - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); - const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); - const SquareDelta TDELTA_S = (Us == WHITE ? DELTA_S : DELTA_N); - - Square to; - Bitboard b1, b2, b3; - Bitboard pawns = pos.pieces(PAWN, Us); + assert(Piece != QUEEN); - if (dc & pawns) + Bitboard b = pos.attacks_from(from) & pos.empty_squares(); + if (Piece == KING) { - Bitboard empty = pos.empty_squares(); - - // Pawn moves which gives discovered check. This is possible only if the - // pawn is not on the same file as the enemy king, because we don't - // generate captures. - b1 = pawns & ~file_bb(ksq); - - // Discovered checks, single pawn pushes, no promotions - b2 = b3 = move_pawns(b1 & dc) & empty & ~TRank8BB; - SERIALIZE_MOVES_D(b3, -TDELTA_N); - - // Discovered checks, double pawn pushes - b3 = move_pawns(b2 & TRank3BB) & empty; - SERIALIZE_MOVES_D(b3, -TDELTA_N -TDELTA_N); + Square ksq = pos.king_square(opposite_color(pos.side_to_move())); + b &= ~QueenPseudoAttacks[ksq]; } - - // Direct checks. These are possible only for pawns on neighboring files - // and in the two ranks that, after the push, are in front of the enemy king. - b1 = pawns & neighboring_files_bb(ksq) & ~dc; - - // We can get false positives if (ksq + x) is not in [0,63] range but - // is not a problem, they will be filtered out later. - b2 = b1 & (rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S)); - if (!b2) - return mlist; - - // Direct checks, single pawn pushes - Bitboard empty = pos.empty_squares(); - b2 = move_pawns(b1) & empty; - b3 = b2 & pos.pawn_attacks(ksq, Them); - SERIALIZE_MOVES_D(b3, -TDELTA_N); - - // Direct checks, double pawn pushes - b3 = move_pawns(b2 & TRank3BB) & empty & pos.pawn_attacks(ksq, Them); - SERIALIZE_MOVES_D(b3, -TDELTA_N -TDELTA_N); + SERIALIZE_MOVES(b); return mlist; } template - MoveStack* generate_piece_checks(const Position& pos, MoveStack* mlist, Color us, + MoveStack* generate_direct_checks(const Position& pos, MoveStack* mlist, Color us, Bitboard dc, Square ksq) { + assert(Piece != KING); - Bitboard target = pos.pieces(Piece, us); - - // Discovered checks - Bitboard b = target & dc; - while (b) - { - Square from = pop_1st_bit(&b); - Bitboard bb = pos.piece_attacks(from) & pos.empty_squares(); - if (Piece == KING) - bb &= ~QueenPseudoAttacks[ksq]; - - SERIALIZE_MOVES(bb); - } - - // Direct checks - b = target & ~dc; - if (Piece != KING || b) - { - Bitboard checkSqs = pos.piece_attacks(ksq) & pos.empty_squares(); - if (!checkSqs) - return mlist; - - while (b) - { - Square from = pop_1st_bit(&b); - if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs)) - || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs)) - || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs))) - continue; - - Bitboard bb = pos.piece_attacks(from) & checkSqs; - SERIALIZE_MOVES(bb); - } - } - return mlist; - } - - template - MoveStack* generate_pawn_blocking_evasions(const Position& pos, Bitboard pinned, - Bitboard blockSquares, MoveStack* mlist) { - - // Calculate our parametrized parameters at compile time - const Rank TRANK_8 = (Us == WHITE ? RANK_8 : RANK_1); - const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); + Square from; + Bitboard checkSqs; + const Square* ptr = pos.piece_list_begin(us, Piece); - Square to; + if ((from = *ptr++) == SQ_NONE) + return mlist; - // Find non-pinned pawns and push them one square - Bitboard b1 = move_pawns(pos.pieces(PAWN, Us) & ~pinned); + checkSqs = pos.attacks_from(ksq) & pos.empty_squares(); - // We don't have to AND with empty squares here, - // because the blocking squares will always be empty. - Bitboard b2 = b1 & blockSquares; - while (b2) + do { - to = pop_1st_bit(&b2); - - assert(pos.piece_on(to) == EMPTY); + if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs)) + || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs)) + || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs))) + continue; - if (square_rank(to) == TRANK_8) - { - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, BISHOP); - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT); - } else - (*mlist++).move = make_move(to - TDELTA_N, to); - } + if (dc && bit_is_set(dc, from)) + continue; - // Double pawn pushes - b2 = b1 & pos.empty_squares() & TRank3BB; - b2 = move_pawns(b2) & blockSquares; - while (b2) - { - to = pop_1st_bit(&b2); + Bitboard bb = pos.attacks_from(from) & checkSqs; + SERIALIZE_MOVES(bb); - assert(pos.piece_on(to) == EMPTY); - assert(Us != WHITE || square_rank(to) == RANK_4); - assert(Us != BLACK || square_rank(to) == RANK_5); + } while ((from = *ptr++) != SQ_NONE); - (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to); - } return mlist; } @@ -942,7 +753,7 @@ namespace { // It is a bit complicated to correctly handle Chess960 for (s = Min(ksq, s1); s <= Max(ksq, s1); s++) if ( (s != ksq && s != rsq && pos.square_is_occupied(s)) - || pos.attacks_to(s, them)) + ||(pos.attackers_to(s) & pos.pieces_of_color(them))) illegal = true; for (s = Min(rsq, s2); s <= Max(rsq, s2); s++) @@ -960,17 +771,4 @@ namespace { } return mlist; } - - bool castling_is_check(const Position& pos, CastlingSide side) { - - // After castling opponent king is attacked by the castled rook? - File rookFile = (side == QUEEN_SIDE ? FILE_D : FILE_F); - Color us = pos.side_to_move(); - Square ksq = pos.king_square(us); - Bitboard occ = pos.occupied_squares(); - - clear_bit(&occ, ksq); // Remove our king from the board - Square rsq = make_square(rookFile, square_rank(ksq)); - return bit_is_set(rook_attacks_bb(rsq, occ), pos.king_square(opposite_color(us))); - } }