X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=0db293ccc7eb713901e139665578821a3b077a9f;hp=da619d1c605e17de1199aa99de245403d60adb79;hb=4dded4e72f9b9582db8adc9a478e9eda5841d8c5;hpb=1c73c1c15026766fb1b77b45d58a0c5b98139ae6 diff --git a/src/movegen.cpp b/src/movegen.cpp index da619d1c..0db293cc 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2009 Marco Costalba + Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -79,7 +79,7 @@ namespace { // Templates for non-capture checks generation template - MoveStack* generate_discovered_checks(const Position& pos, MoveStack* mlist, Square from); + MoveStack* generate_discovered_checks(const Position&, MoveStack*, Square); template MoveStack* generate_direct_checks(const Position&, MoveStack*, Color, Bitboard, Square); @@ -140,6 +140,32 @@ MoveStack* generate_noncaptures(const Position& pos, MoveStack* mlist) { } +/// generate_non_evasions() generates all pseudo-legal captures and +/// non-captures. Returns a pointer to the end of the move list. + +MoveStack* generate_non_evasions(const Position& pos, MoveStack* mlist) { + + assert(pos.is_ok()); + assert(!pos.is_check()); + + Color us = pos.side_to_move(); + Bitboard target = pos.pieces_of_color(opposite_color(us)); + + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, pos.empty_squares()); + + target |= pos.empty_squares(); + + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_castle_moves(pos, mlist); + return generate_castle_moves(pos, mlist); +} + + /// generate_non_capture_checks() generates all pseudo-legal non-captures and knight /// underpromotions that give check. Returns a pointer to the end of the move list. @@ -148,17 +174,19 @@ MoveStack* generate_non_capture_checks(const Position& pos, MoveStack* mlist) { assert(pos.is_ok()); assert(!pos.is_check()); + Bitboard b, dc; + Square from; Color us = pos.side_to_move(); Square ksq = pos.king_square(opposite_color(us)); - Bitboard dc = pos.discovered_check_candidates(us); assert(pos.piece_on(ksq) == piece_of_color_and_type(opposite_color(us), KING)); // Discovered non-capture checks - Bitboard b = dc; + b = dc = pos.discovered_check_candidates(us); + while (b) { - Square from = pop_1st_bit(&b); + from = pop_1st_bit(&b); switch (pos.type_of_piece_on(from)) { case PAWN: /* Will be generated togheter with pawns direct checks */ break; @@ -187,7 +215,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist) { assert(pos.is_ok()); assert(pos.is_check()); - Bitboard b; + Bitboard b, target; Square from, checksq; int checkersCnt = 0; Color us = pos.side_to_move(); @@ -216,7 +244,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist) { case QUEEN: // In case of a queen remove also squares attacked in the other direction to // avoid possible illegal moves when queen and king are on adjacent squares. - if (direction_is_straight(checksq, ksq)) + if (squares_straight_aligned(checksq, ksq)) sliderAttacks |= RookPseudoAttacks[checksq] | pos.attacks_from(checksq); else sliderAttacks |= BishopPseudoAttacks[checksq] | pos.attacks_from(checksq); @@ -236,7 +264,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist) { // Find squares where a blocking evasion or a capture of the // checker piece is possible. - Bitboard target = squares_between(checksq, ksq) | checkers; + target = squares_between(checksq, ksq) | checkers; mlist = generate_piece_moves(pos, mlist, us, target); mlist = generate_piece_moves(pos, mlist, us, target); @@ -254,26 +282,22 @@ MoveStack* generate_moves(const Position& pos, MoveStack* mlist, bool pseudoLega assert(pos.is_ok()); - MoveStack* last; + MoveStack *last, *cur = mlist; Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); // Generate pseudo-legal moves - if (pos.is_check()) - last = generate_evasions(pos, mlist); - else { - last = generate_captures(pos, mlist); - last = generate_noncaptures(pos, last); - } + last = pos.is_check() ? generate_evasions(pos, mlist) + : generate_non_evasions(pos, mlist); if (pseudoLegal) return last; // Remove illegal moves from the list - for (MoveStack* cur = mlist; cur != last; cur++) - if (!pos.pl_move_is_legal(cur->move, pinned)) - { + while (cur != last) + if (pos.pl_move_is_legal(cur->move, pinned)) + cur++; + else cur->move = (--last)->move; - cur--; - } + return last; } @@ -284,9 +308,10 @@ MoveStack* generate_moves(const Position& pos, MoveStack* mlist, bool pseudoLega 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++) + MoveStack mlist[MOVES_MAX]; + MoveStack *cur, *last = generate_moves(pos, mlist, true); + + for (cur = mlist; cur != last; cur++) if (cur->move == m) return pos.pl_move_is_legal(m, pos.pinned_pieces(pos.side_to_move())); @@ -303,16 +328,16 @@ 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); + // Use a slower but simpler function for uncommon cases + if (move_is_special(m)) + return move_is_legal(pos, m); + // If the from square is not occupied by a piece belonging to the side to // move, the move is obviously not legal. if (color_of_piece(pc) != us) @@ -330,10 +355,9 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { if ((us == WHITE) != (direction > 0)) return false; - // 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))) + // We have already handled promotion moves, so destination + // cannot be on the 8/1th rank. + if (square_rank(to) == RANK_8 || square_rank(to) == RANK_1) return false; // Proceed according to the square delta between the origin and @@ -380,14 +404,12 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { default: return false; } - // The move is pseudo-legal, check if it is also legal - return pos.is_check() ? pos.pl_move_is_evasion(m, pinned) : pos.pl_move_is_legal(m, pinned); } + else if (!bit_is_set(pos.attacks_from(pc, from), to)) + return false; - // Luckly we can handle all the other pieces in one go - return bit_is_set(pos.attacks_from(pc, from), to) - && (pos.is_check() ? pos.pl_move_is_evasion(m, pinned) : pos.pl_move_is_legal(m, pinned)) - && !move_is_promotion(m); + // The move is pseudo-legal, check if it is also legal + return pos.is_check() ? pos.pl_move_is_evasion(m, pinned) : pos.pl_move_is_legal(m, pinned); } @@ -396,14 +418,17 @@ namespace { template MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { - Square from; Bitboard b; + Square from; const Square* ptr = pos.piece_list_begin(us, Piece); - while ((from = *ptr++) != SQ_NONE) + if (*ptr != SQ_NONE) { - b = pos.attacks_from(from) & target; - SERIALIZE_MOVES(b); + do { + from = *ptr; + b = pos.attacks_from(from) & target; + SERIALIZE_MOVES(b); + } while (*++ptr != SQ_NONE); } return mlist; } @@ -419,152 +444,135 @@ namespace { return mlist; } - template + 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; + return Delta == DELTA_N ? p << 8 : Delta == DELTA_S ? p >> 8 : + Delta == DELTA_NE ? p << 9 : Delta == DELTA_SE ? p >> 7 : + Delta == DELTA_NW ? p << 7 : Delta == DELTA_SW ? p >> 9 : p; } - template - inline MoveStack* generate_pawn_captures(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool possiblePromotion) { + template + inline MoveStack* generate_pawn_captures(MoveStack* mlist, Bitboard pawns, Bitboard target) { - // Calculate our parametrized parameters at compile time - const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); - const Bitboard TFileABB = (Diagonal == DELTA_NE ? FileABB : FileHBB); - const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE); - const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW); - const SquareDelta TTDELTA_NE = (Diagonal == DELTA_NE ? TDELTA_NE : TDELTA_NW); + const Bitboard TFileABB = (Delta == DELTA_NE || Delta == DELTA_SE ? FileABB : FileHBB); + Bitboard b; Square to; // Captures in the a1-h8 (a8-h1 for black) diagonal or in the h1-a8 (h8-a1 for black) - Bitboard b1 = move_pawns(pawns) & ~TFileABB & enemyPieces; + b = move_pawns(pawns) & target & ~TFileABB; + SERIALIZE_MOVES_D(b, -Delta); + return mlist; + } - // Capturing promotions and under-promotions - if (possiblePromotion) - { - Bitboard b2 = b1 & TRank8BB; - b1 &= ~TRank8BB; - while (b2) - { - to = pop_1st_bit(&b2); + template + inline MoveStack* generate_promotions(const Position& pos, MoveStack* mlist, Bitboard pawnsOn7, Bitboard target) { - if (Type == CAPTURE || Type == EVASION) - (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, QUEEN); + const Bitboard TFileABB = (Delta == DELTA_NE || Delta == DELTA_SE ? FileABB : FileHBB); - if (Type == NON_CAPTURE || Type == EVASION) - { - (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, ROOK); - (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, BISHOP); - (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, KNIGHT); - } + Bitboard b; + Square to; - // This is the only possible under promotion that can give a check - // not already included in the queen-promotion. It is not sure that - // the promoted knight will give check, but it doesn't worth to verify. - if (Type == CHECK) - (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, KNIGHT); - } - } + // Promotions and under-promotions, both captures and non-captures + b = move_pawns(pawnsOn7) & target; - // Serialize standard captures - if (Type == CAPTURE || Type == EVASION) - SERIALIZE_MOVES_D(b1, -TTDELTA_NE); + if (Delta != DELTA_N && Delta != DELTA_S) + b &= ~TFileABB; + while (b) + { + to = pop_1st_bit(&b); + + if (Type == CAPTURE || Type == EVASION) + (*mlist++).move = make_promotion_move(to - Delta, to, QUEEN); + + if (Type == NON_CAPTURE || Type == EVASION) + { + (*mlist++).move = make_promotion_move(to - Delta, to, ROOK); + (*mlist++).move = make_promotion_move(to - Delta, to, BISHOP); + (*mlist++).move = make_promotion_move(to - Delta, to, KNIGHT); + } + + // This is the only possible under promotion that can give a check + // not already included in the queen-promotion. + if ( Type == CHECK + && bit_is_set(pos.attacks_from(to), pos.king_square(opposite_color(Us)))) + (*mlist++).move = make_promotion_move(to - Delta, to, KNIGHT); + else (void)pos; // Silence a warning under MSVC + } return mlist; } template MoveStack* generate_pawn_moves(const Position& pos, MoveStack* mlist, Bitboard target, Square ksq) { - // 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_N = (Us == WHITE ? DELTA_N : DELTA_S); + // Calculate our parametrized parameters at compile time, named + // according to the point of view of white side. + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); + const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE); + const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW); Square to; - Bitboard b1, b2, enemyPieces, emptySquares; + Bitboard b1, b2, dc1, dc2, pawnPushes, emptySquares; Bitboard pawns = pos.pieces(PAWN, Us); - bool possiblePromotion = pawns & TRank7BB; + Bitboard pawnsOn7 = pawns & TRank7BB; + Bitboard enemyPieces = (Type == CAPTURE ? target : pos.pieces_of_color(Them)); - // Standard captures and capturing promotions and underpromotions - if (Type == CAPTURE || Type == EVASION || possiblePromotion) + // Pre-calculate pawn pushes before changing emptySquares definition + if (Type != CAPTURE) { - enemyPieces = (Type == CAPTURE ? target : pos.pieces_of_color(opposite_color(Us))); - - if (Type == EVASION) - enemyPieces &= target; // Capture only the checker piece - - mlist = generate_pawn_captures(mlist, pawns, enemyPieces, possiblePromotion); - mlist = generate_pawn_captures(mlist, pawns, enemyPieces, possiblePromotion); + emptySquares = (Type == NON_CAPTURE ? target : pos.empty_squares()); + pawnPushes = move_pawns(pawns & ~TRank7BB) & emptySquares; } - // Non-capturing promotions and underpromotions - if (possiblePromotion) + if (Type == EVASION) { - b1 = move_pawns(pawns) & TRank8BB & pos.empty_squares(); - - if (Type == EVASION) - b1 &= target; // Only blocking promotion pushes - - while (b1) - { - to = pop_1st_bit(&b1); + emptySquares &= target; // Only blocking squares + enemyPieces &= target; // Capture only the checker piece + } - if (Type == CAPTURE || Type == EVASION) - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN); + // Promotions and underpromotions + if (pawnsOn7) + { + if (Type == CAPTURE) + emptySquares = pos.empty_squares(); - if (Type == NON_CAPTURE || Type == EVASION) - { - (*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); - } + pawns &= ~TRank7BB; + mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); + mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); + mlist = generate_promotions(pos, mlist, pawnsOn7, emptySquares); + } - // This is the only possible under promotion that can give a check - // not already included in the queen-promotion. - if (Type == CHECK && bit_is_set(pos.attacks_from(to), pos.king_square(Them))) - (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT); - } + // Standard captures + if (Type == CAPTURE || Type == EVASION) + { + mlist = generate_pawn_captures(mlist, pawns, enemyPieces); + mlist = generate_pawn_captures(mlist, pawns, enemyPieces); } - // Standard pawn pushes and double pushes + // Single and double pawn pushes if (Type != CAPTURE) { - emptySquares = (Type == NON_CAPTURE ? target : pos.empty_squares()); - - // Single and double pawn pushes - b1 = move_pawns(pawns) & emptySquares & ~TRank8BB; - b2 = move_pawns(b1 & TRank3BB) & emptySquares; + b1 = pawnPushes & emptySquares; + b2 = move_pawns(pawnPushes & TRank3BB) & emptySquares; - // Filter out unwanted pushes according to the move type - if (Type == EVASION) + if (Type == CHECK) { - b1 &= target; - b2 &= target; - } - else if (Type == CHECK) - { - // Pawn moves which give direct cheks + // Condider only pawn moves which give direct checks b1 &= pos.attacks_from(ksq, Them); b2 &= pos.attacks_from(ksq, Them); - // 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. + // Add 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. if (pawns & target) // For CHECK type target is dc bitboard { - Bitboard dc1 = move_pawns(pawns & target & ~file_bb(ksq)) & emptySquares & ~TRank8BB; - Bitboard dc2 = move_pawns(dc1 & TRank3BB) & emptySquares; + dc1 = move_pawns(pawns & target & ~file_bb(ksq)) & emptySquares; + dc2 = move_pawns(dc1 & TRank3BB) & emptySquares; b1 |= dc1; b2 |= dc2; @@ -619,8 +627,8 @@ namespace { Bitboard dc, Square ksq) { assert(Piece != KING); + Bitboard checkSqs, b; Square from; - Bitboard checkSqs; const Square* ptr = pos.piece_list_begin(us, Piece); if ((from = *ptr++) == SQ_NONE) @@ -638,8 +646,8 @@ namespace { if (dc && bit_is_set(dc, from)) continue; - Bitboard bb = pos.attacks_from(from) & checkSqs; - SERIALIZE_MOVES(bb); + b = pos.attacks_from(from) & checkSqs; + SERIALIZE_MOVES(b); } while ((from = *ptr++) != SQ_NONE); @@ -651,7 +659,7 @@ namespace { Color us = pos.side_to_move(); - if ( (Side == KING_SIDE && pos.can_castle_kingside(us)) + if ( (Side == KING_SIDE && pos.can_castle_kingside(us)) ||(Side == QUEEN_SIDE && pos.can_castle_queenside(us))) { Color them = opposite_color(us);