X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=9a6b902bb3efc8b66d2b08a52f63bbad7419a0d5;hp=9781f9a9e0e8cabb53d98bdb9dd0b3da2eea892a;hb=46bb6c6dc300bc5a8b819d690734ddcb1f1e4e14;hpb=214f9dcc278dd322b94f4922924219a970b95009 diff --git a/src/movegen.cpp b/src/movegen.cpp index 9781f9a9..9a6b902b 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -40,8 +40,10 @@ namespace { QUEEN_SIDE }; - const bool CAPTURE = true; - const bool NON_CAPTURE = false; + enum MoveType { + CAPTURE, + NON_CAPTURE + }; // Functions bool castling_is_check(const Position&, CastlingSide); @@ -62,6 +64,19 @@ namespace { template MoveStack* generate_pawn_checks(const Position&, Bitboard, Square, MoveStack*); + template + inline Bitboard move_pawns(Bitboard p) { + + 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 generate_piece_checks() with specializations template MoveStack* generate_piece_checks(const Position&, MoveStack*, Color, Bitboard, Square); @@ -76,19 +91,19 @@ namespace { } - // Template generate_piece_moves() with specializations + // Template generate_piece_moves() with specializations and overloads template MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard); template<> - MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target); + MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); - template + template inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us) { assert(Piece == PAWN); - if (Capture) + if (Type == CAPTURE) return (us == WHITE ? generate_pawn_captures(p, m) : generate_pawn_captures(p, m)); else @@ -96,17 +111,16 @@ namespace { : generate_pawn_noncaptures(p, m)); } - // Template generate_piece_blocking_evasions() with specializations template - MoveStack* generate_piece_blocking_evasions(const Position&, MoveStack*, Color us, Bitboard, Bitboard); + MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard, Bitboard); template<> - inline MoveStack* generate_piece_blocking_evasions(const Position& p, MoveStack* m, Color us, - Bitboard pnd, Bitboard bs) { + inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, + Color us, Bitboard t, Bitboard pnd) { if (us == WHITE) - return generate_pawn_blocking_evasions(p, pnd, bs, m); + return generate_pawn_blocking_evasions(p, pnd, t, m); else - return generate_pawn_blocking_evasions(p, pnd, bs, m); + return generate_pawn_blocking_evasions(p, pnd, t, m); } } @@ -162,10 +176,10 @@ int generate_noncaptures(const Position& pos, MoveStack* mlist) { } -/// generate_checks() generates all pseudo-legal non-capturing, non-promoting -/// checks. It returns the number of generated moves. +/// generate_non_capture_checks() generates all pseudo-legal non-capturing, +/// non-promoting checks. It returns the number of generated moves. -int generate_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { +int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { assert(pos.is_ok()); assert(!pos.is_check()); @@ -174,7 +188,7 @@ int generate_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { Square ksq = pos.king_square(opposite_color(us)); MoveStack* mlist_start = mlist; - assert(pos.piece_on(ksq) == king_of_color(opposite_color(us))); + 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); @@ -200,9 +214,8 @@ int generate_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { /// generate_evasions() generates all check evasions when the side to move is -/// in check. Unlike the other move generation functions, this one generates -/// only legal moves. It returns the number of generated moves. This -/// function is very ugly, and needs cleaning up some time later. FIXME +/// in check. Unlike the other move generation functions, this one generates +/// only legal moves. It returns the number of generated moves. int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { @@ -215,29 +228,30 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { Square ksq = pos.king_square(us); MoveStack* mlist_start = mlist; - assert(pos.piece_on(ksq) == king_of_color(us)); + assert(pos.piece_on(ksq) == piece_of_color_and_type(us, KING)); // The bitboard of occupied pieces without our king - Bitboard b2 = pos.occupied_squares(); - clear_bit(&b2, ksq); + 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 - // of cycles in the slow king evasions legality check loop. + // of cycles in the slow king evasions legality check loop + // and to be able to use square_is_attacked(). Bitboard checkers = pos.checkers(); Bitboard checkersAttacks = EmptyBoardBB; Bitboard b = checkers & (pos.queens() | pos.bishops()); while (b) { from = pop_1st_bit(&b); - checkersAttacks |= bishop_attacks_bb(from, b2); + checkersAttacks |= bishop_attacks_bb(from, b_noKing); } b = checkers & (pos.queens() | pos.rooks()); while (b) { from = pop_1st_bit(&b); - checkersAttacks |= rook_attacks_bb(from, b2); + checkersAttacks |= rook_attacks_bb(from, b_noKing); } // Generate evasions for king @@ -245,17 +259,9 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { while (b1) { to = pop_1st_bit(&b1); - - // Make sure 'to' is not attacked by the other side. This is a bit ugly, - // because we can't use Position::square_is_attacked. Instead we use - // the low-level bishop_attacks_bb and rook_attacks_bb with the bitboard - // b2 (the occupied squares with the king removed) in order to test whether - // the king will remain in check on the destination square. - if (!( (pos.piece_attacks(to) & pos.knights(them)) - || (pos.pawn_attacks(us, to) & pos.pawns(them)) - || (bishop_attacks_bb(to, b2) & pos.bishops_and_queens(them)) - || (rook_attacks_bb(to, b2) & pos.rooks_and_queens(them)) - || (pos.piece_attacks(to) & pos.kings(them)))) + // Note that we can use square_is_attacked() only because we + // have already removed slider checkers. + if (!pos.square_is_attacked(to, them)) (*mlist++).move = make_move(ksq, to); } @@ -304,39 +310,41 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { assert((pos.occupied_squares() & blockSquares) == EmptyBoardBB); - // Pieces moves - mlist = generate_piece_blocking_evasions(pos, mlist, us, pinned, blockSquares); - mlist = generate_piece_blocking_evasions(pos, mlist, us, pinned, blockSquares); - mlist = generate_piece_blocking_evasions(pos, mlist, us, pinned, blockSquares); - mlist = generate_piece_blocking_evasions(pos, mlist, us, pinned, blockSquares); - mlist = generate_piece_blocking_evasions(pos, mlist, us, pinned, blockSquares); - } + if (blockSquares != EmptyBoardBB) + { + 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); + } + } - // Finally, the ugly special case of en passant captures. An en passant - // capture can only be a check evasion if the check is not a discovered - // check. If pos.ep_square() is set, the last move made must have been - // a double pawn push. If, furthermore, the checking piece is a pawn, - // an en passant check evasion may be possible. - if (pos.ep_square() != SQ_NONE && (checkers & pos.pawns(them))) - { - to = pos.ep_square(); - b1 = pos.pawn_attacks(them, to) & pos.pawns(us); + // Finally, the special case of en passant captures. An en passant + // capture can only be a check evasion if the check is not a discovered + // check. If pos.ep_square() is set, the last move made must have been + // a double pawn push. If, furthermore, the checking piece is a pawn, + // an en passant check evasion may be possible. + if (pos.ep_square() != SQ_NONE && (checkers & pos.pawns(them))) + { + to = pos.ep_square(); + b1 = pos.pawn_attacks(them, to) & pos.pawns(us); - // The checking pawn cannot be a discovered (bishop) check candidate - // otherwise we were in check also before last double push move. - assert(!bit_is_set(pos.discovered_check_candidates(them), checksq)); - assert(count_1s(b1) == 1 || count_1s(b1) == 2); + // The checking pawn cannot be a discovered (bishop) check candidate + // otherwise we were in check also before last double push move. + assert(!bit_is_set(pos.discovered_check_candidates(them), checksq)); + assert(count_1s(b1) == 1 || count_1s(b1) == 2); - b1 &= ~pinned; - while (b1) - { - from = pop_1st_bit(&b1); - // Move is always legal because checking pawn is not a discovered - // check candidate and our capturing pawn has been already tested - // against pinned pieces. - (*mlist++).move = make_ep_move(from, to); - } - } + b1 &= ~pinned; + while (b1) + { + from = pop_1st_bit(&b1); + // Move is always legal because checking pawn is not a discovered + // check candidate and our capturing pawn has been already tested + // against pinned pieces. + (*mlist++).move = make_ep_move(from, to); + } + } } return int(mlist - mlist_start); } @@ -405,7 +413,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { return false; assert(pos.square_is_empty(to)); - assert(pos.piece_on(to - pawn_push(us)) == pawn_of_color(them)); + 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); @@ -422,7 +430,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { assert(from == pos.king_square(us)); assert(to == pos.initial_kr_square(us)); - assert(pos.piece_on(to) == rook_of_color(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); @@ -455,7 +463,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { assert(from == pos.king_square(us)); assert(to == pos.initial_qr_square(us)); - assert(pos.piece_on(to) == rook_of_color(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); @@ -472,8 +480,8 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { illegal = true; if ( square_file(to) == FILE_B - && ( pos.piece_on(to + DELTA_W) == rook_of_color(them) - || pos.piece_on(to + DELTA_W) == queen_of_color(them))) + && ( 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; @@ -488,6 +496,11 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { // Proceed according to the type of the moving piece. if (type_of_piece(pc) == PAWN) { + // Move direction must be compatible with pawn color + int direction = to - from; + 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) @@ -497,7 +510,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { // Proceed according to the square delta between the source and // destionation squares. - switch (to - from) + switch (direction) { case DELTA_NW: case DELTA_NE: @@ -544,7 +557,7 @@ 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(from, to) + return ( pos.piece_attacks_square(pos.piece_on(from), from, to) && pos.pl_move_is_legal(m, pinned) && !move_promotion(m)); } @@ -567,20 +580,9 @@ namespace { 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.piece_attacks(from) & target; - SERIALIZE_MOVES(b); - return mlist; - } - template - MoveStack* generate_piece_blocking_evasions(const Position& pos, MoveStack* mlist, Color us, - Bitboard pinned, Bitboard blockSquares) { + MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, + Color us, Bitboard target, Bitboard pinned) { Square from; Bitboard b; @@ -590,12 +592,23 @@ namespace { if (pinned && bit_is_set(pinned, from)) continue; - b = pos.piece_attacks(from) & blockSquares; + b = pos.piece_attacks(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.piece_attacks(from) & target; + SERIALIZE_MOVES(b); + return mlist; + } + template @@ -606,7 +619,7 @@ namespace { Bitboard enemyPieces = pos.pieces_of_color(Them); // Captures in the a1-h8 (a8-h1 for black) direction - Bitboard b1 = (Us == WHITE ? pawns << 9 : pawns >> 7) & ~FileABB & enemyPieces; + Bitboard b1 = move_pawns(pawns) & ~FileABB & enemyPieces; // Capturing promotions Bitboard b2 = b1 & TRank8BB; @@ -625,7 +638,7 @@ namespace { } // Captures in the h1-a8 (h8-a1 for black) direction - b1 = (Us == WHITE ? pawns << 7 : pawns >> 9) & ~FileHBB & enemyPieces; + b1 = move_pawns(pawns) & ~FileHBB & enemyPieces; // Capturing promotions b2 = b1 & TRank8BB; @@ -644,7 +657,7 @@ namespace { } // Non-capturing promotions - b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & pos.empty_squares() & TRank8BB; + b1 = move_pawns(pawns) & pos.empty_squares() & TRank8BB; while (b1) { to = pop_1st_bit(&b1); @@ -681,7 +694,7 @@ namespace { Square to; // Underpromotion captures in the a1-h8 (a8-h1 for black) direction - b1 = (Us == WHITE ? pawns << 9 : pawns >> 7) & ~FileABB & enemyPieces & TRank8BB; + b1 = move_pawns(pawns) & ~FileABB & enemyPieces & TRank8BB; while (b1) { to = pop_1st_bit(&b1); @@ -691,7 +704,7 @@ namespace { } // Underpromotion captures in the h1-a8 (h8-a1 for black) direction - b1 = (Us == WHITE ? pawns << 7 : pawns >> 9) & ~FileHBB & enemyPieces & TRank8BB; + b1 = move_pawns(pawns) & ~FileHBB & enemyPieces & TRank8BB; while (b1) { to = pop_1st_bit(&b1); @@ -701,7 +714,7 @@ namespace { } // Single pawn pushes - b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & emptySquares; + b1 = move_pawns(pawns) & emptySquares; b2 = b1 & TRank8BB; while (b2) { @@ -718,7 +731,7 @@ namespace { } // Double pawn pushes - b2 = (Us == WHITE ? (b1 & TRank3BB) << 8 : (b1 & TRank3BB) >> 8) & emptySquares; + b2 = move_pawns(b1 & TRank3BB) & emptySquares; while (b2) { to = pop_1st_bit(&b2); @@ -743,7 +756,7 @@ namespace { b1 = pos.pawns(Us) & ~file_bb(ksq); // Discovered checks, single pawn pushes, no promotions - b2 = b3 = (Us == WHITE ? (b1 & dc) << 8 : (b1 & dc) >> 8) & empty & ~TRank8BB; + b2 = b3 = move_pawns(b1 & dc) & empty & ~TRank8BB; while (b3) { Square to = pop_1st_bit(&b3); @@ -751,7 +764,7 @@ namespace { } // Discovered checks, double pawn pushes - b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8) & empty; + b3 = move_pawns(b2 & TRank3BB) & empty; while (b3) { Square to = pop_1st_bit(&b3); @@ -764,7 +777,7 @@ namespace { b1 = pos.pawns(Us) & neighboring_files_bb(ksq) & ~dc; // Direct checks, single pawn pushes - b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & empty; + b2 = move_pawns(b1) & empty; b3 = b2 & pos.pawn_attacks(Them, ksq); while (b3) { @@ -773,9 +786,7 @@ namespace { } // Direct checks, double pawn pushes - b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8) - & empty - & pos.pawn_attacks(Them, ksq); + b3 = move_pawns(b2 & TRank3BB) & empty & pos.pawn_attacks(Them, ksq); while (b3) { Square to = pop_1st_bit(&b3); @@ -808,9 +819,17 @@ namespace { return mlist; 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); } @@ -822,12 +841,12 @@ namespace { Bitboard blockSquares, MoveStack* mlist) { Square to; - // Find non-pinned pawns - Bitboard b1 = pos.pawns(Us) & ~pinned; + // Find non-pinned pawns and push them one square + Bitboard b1 = move_pawns(pos.pawns(Us) & ~pinned); - // Single pawn pushes. We don't have to AND with empty squares here, + // We don't have to AND with empty squares here, // because the blocking squares will always be empty. - Bitboard b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & blockSquares; + Bitboard b2 = b1 & blockSquares; while (b2) { to = pop_1st_bit(&b2); @@ -845,8 +864,8 @@ namespace { } // Double pawn pushes - b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & pos.empty_squares() & TRank3BB; - b2 = (Us == WHITE ? b2 << 8 : b2 >> 8) & blockSquares; + b2 = b1 & pos.empty_squares() & TRank3BB; + b2 = move_pawns(b2) & blockSquares; while (b2) { to = pop_1st_bit(&b2); @@ -871,7 +890,7 @@ namespace { Color them = opposite_color(us); Square ksq = pos.king_square(us); - assert(pos.piece_on(ksq) == king_of_color(us)); + assert(pos.piece_on(ksq) == piece_of_color_and_type(us, KING)); Square rsq = (Side == KING_SIDE ? pos.initial_kr_square(us) : pos.initial_qr_square(us)); Square s1 = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1); @@ -879,7 +898,7 @@ namespace { Square s; bool illegal = false; - assert(pos.piece_on(rsq) == rook_of_color(us)); + assert(pos.piece_on(rsq) == piece_of_color_and_type(us, ROOK)); // It is a bit complicated to correctly handle Chess960 for (s = Min(ksq, s1); s <= Max(ksq, s1); s++) @@ -893,8 +912,8 @@ namespace { if ( Side == QUEEN_SIDE && square_file(rsq) == FILE_B - && ( pos.piece_on(relative_square(us, SQ_A1)) == rook_of_color(them) - || pos.piece_on(relative_square(us, SQ_A1)) == queen_of_color(them))) + && ( pos.piece_on(relative_square(us, SQ_A1)) == piece_of_color_and_type(them, ROOK) + || pos.piece_on(relative_square(us, SQ_A1)) == piece_of_color_and_type(them, QUEEN))) illegal = true; if (!illegal)