X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=1135c21976f416a9bf0116f0936972dc9bde2afe;hp=37e66724e5decd81e25a8eaecd552264f200e2c1;hb=f1591447cf791b6c0ed4710df7eb688c65c4c20e;hpb=1b0fee9b17a1220b60b3051626e8444f474e884c diff --git a/src/movegen.cpp b/src/movegen.cpp index 37e66724..1135c219 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,6 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008 Marco Costalba + Copyright (C) 2004-2008 Tord Romstad (Glaurung author) + Copyright (C) 2008-2009 Marco Costalba Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -23,6 +24,7 @@ #include +#include "bitcount.h" #include "movegen.h" // Simple macro to wrap a very common while loop, no facny, no flexibility, @@ -52,18 +54,34 @@ namespace { template MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist); - template + template MoveStack* generate_pawn_blocking_evasions(const Position&, Bitboard, Bitboard, MoveStack*); - template + template MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist); - template + template + MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces); + + template MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist); - template + 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); @@ -71,11 +89,8 @@ namespace { template<> inline MoveStack* generate_piece_checks(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) { - if (us == WHITE) - return generate_pawn_checks(p, dc, ksq, m); - else - return generate_pawn_checks(p, dc, ksq, m); - + return (us == WHITE ? generate_pawn_checks(p, dc, ksq, m) + : generate_pawn_checks(p, dc, ksq, m)); } // Template generate_piece_moves() with specializations and overloads @@ -91,11 +106,11 @@ namespace { assert(Piece == PAWN); if (Type == CAPTURE) - return (us == WHITE ? generate_pawn_captures(p, m) - : generate_pawn_captures(p, m)); + 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_noncaptures(p, m) + : generate_pawn_noncaptures(p, m)); } template @@ -104,10 +119,9 @@ namespace { template<> 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, t, m); - else - return generate_pawn_blocking_evasions(p, pnd, t, m); + + return (us == WHITE ? generate_pawn_blocking_evasions(p, pnd, t, m) + : generate_pawn_blocking_evasions(p, pnd, t, m)); } } @@ -163,17 +177,16 @@ 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) { +int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { assert(pos.is_ok()); assert(!pos.is_check()); Color us = pos.side_to_move(); Square ksq = pos.king_square(opposite_color(us)); - Bitboard dc = pos.discovered_check_candidates(us); MoveStack* mlist_start = mlist; assert(pos.piece_on(ksq) == piece_of_color_and_type(opposite_color(us), KING)); @@ -205,7 +218,7 @@ int generate_checks(const Position& pos, MoveStack* mlist) { /// 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) { +int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { assert(pos.is_ok()); assert(pos.is_check()); @@ -259,7 +272,6 @@ int generate_evasions(const Position& pos, MoveStack* mlist) { if (!(checkers & (checkers - 1))) // Only one bit set? { Square checksq = first_1(checkers); - Bitboard pinned = pos.pinned_pieces(us); assert(pos.color_of_piece_on(checksq) == them); @@ -349,8 +361,10 @@ int generate_legal_moves(const Position& pos, MoveStack* mlist) { assert(pos.is_ok()); + Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); + if (pos.is_check()) - return generate_evasions(pos, mlist); + return generate_evasions(pos, mlist, pinned); // Generate pseudo-legal moves int n = generate_captures(pos, mlist); @@ -358,7 +372,7 @@ int generate_legal_moves(const Position& pos, MoveStack* mlist) { // Remove illegal moves from the list for (int i = 0; i < n; i++) - if (!pos.pl_move_is_legal(mlist[i].move)) + if (!pos.pl_move_is_legal(mlist[i].move, pinned)) mlist[i--].move = mlist[--n].move; return n; @@ -371,11 +385,12 @@ int generate_legal_moves(const Position& pos, MoveStack* mlist) { /// returned. If not, the function returns false. This function must /// only be used when the side to move is not in check. -bool move_is_legal(const Position& pos, const Move m) { +bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { assert(pos.is_ok()); assert(!pos.is_check()); assert(move_is_ok(m)); + assert(pinned == pos.pinned_pieces(pos.side_to_move())); Color us = pos.side_to_move(); Color them = opposite_color(us); @@ -402,7 +417,7 @@ bool move_is_legal(const Position& pos, const Move m) { 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); + return pos.pl_move_is_legal(m, pinned); } // Castling moves @@ -482,6 +497,11 @@ bool move_is_legal(const Position& pos, const Move m) { // 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) @@ -491,7 +511,7 @@ bool move_is_legal(const Position& pos, const Move m) { // Proceed according to the square delta between the source and // destionation squares. - switch (to - from) + switch (direction) { case DELTA_NW: case DELTA_NE: @@ -534,12 +554,12 @@ bool move_is_legal(const Position& pos, const Move m) { return false; } // The move is pseudo-legal, check if it is also legal - return pos.pl_move_is_legal(m); + return pos.pl_move_is_legal(m, pinned); } // Luckly we can handle all the other pieces in one go return ( pos.piece_attacks_square(pos.piece_on(from), from, to) - && pos.pl_move_is_legal(m) + && pos.pl_move_is_legal(m, pinned) && !move_promotion(m)); } @@ -590,24 +610,27 @@ namespace { return mlist; } - template - MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) { + template + MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces) { + + // 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); Square to; - Bitboard pawns = pos.pawns(Us); - 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; + // 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; // Capturing promotions Bitboard b2 = b1 & TRank8BB; while (b2) { to = pop_1st_bit(&b2); - (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, QUEEN); + (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, QUEEN); } // Capturing non-promotions @@ -615,30 +638,29 @@ namespace { while (b2) { to = pop_1st_bit(&b2); - (*mlist++).move = make_move(to - TDELTA_NE, to); + (*mlist++).move = make_move(to - TTDELTA_NE, to); } + return mlist; + } - // Captures in the h1-a8 (h8-a1 for black) direction - b1 = (Us == WHITE ? pawns << 7 : pawns >> 9) & ~FileHBB & enemyPieces; + template + MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) { - // Capturing promotions - b2 = b1 & TRank8BB; - while (b2) - { - to = pop_1st_bit(&b2); - (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, QUEEN); - } + // Calculate our parametrized parameters at compile time + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); + const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); - // Capturing non-promotions - b2 = b1 & ~TRank8BB; - while (b2) - { - to = pop_1st_bit(&b2); - (*mlist++).move = make_move(to - TDELTA_NW, to); - } + Square to; + Bitboard pawns = pos.pawns(Us); + Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); + + // Standard captures and capturing promotions in both directions + mlist = generate_pawn_captures_diagonal(mlist, pawns, enemyPieces); + mlist = generate_pawn_captures_diagonal(mlist, pawns, enemyPieces); // Non-capturing promotions - b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & pos.empty_squares() & TRank8BB; + Bitboard b1 = move_pawns(pawns) & pos.empty_squares() & TRank8BB; while (b1) { to = pop_1st_bit(&b1); @@ -663,19 +685,24 @@ namespace { return mlist; } - template + template MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist) { - Bitboard pawns = pos.pawns(Us); - Bitboard enemyPieces = pos.pieces_of_color(Them); - Bitboard emptySquares = pos.empty_squares(); + // Calculate our parametrized parameters at compile time + const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); + 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.pawns(Us); + Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us)); + Bitboard emptySquares = pos.empty_squares(); // 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); @@ -685,7 +712,7 @@ 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); @@ -695,7 +722,7 @@ namespace { } // Single pawn pushes - b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & emptySquares; + b1 = move_pawns(pawns) & emptySquares; b2 = b1 & TRank8BB; while (b2) { @@ -712,7 +739,7 @@ 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); @@ -722,22 +749,30 @@ namespace { } - template + template MoveStack* generate_pawn_checks(const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist) { - // Find all friendly pawns not on the enemy king's file + // 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); + Bitboard b1, b2, b3; - Bitboard empty = pos.empty_squares(); + Bitboard pawns = pos.pawns(Us); - if (dc != EmptyBoardBB) + if (dc & pawns) { + 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 = pos.pawns(Us) & ~file_bb(ksq); + b1 = pawns & ~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); @@ -745,7 +780,7 @@ 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); @@ -754,11 +789,16 @@ namespace { } // Direct checks. These are possible only for pawns on neighboring files - // of the enemy king. - b1 = pos.pawns(Us) & neighboring_files_bb(ksq) & ~dc; + // and in the two ranks that, after the push, are in front of the enemy king. + b1 = pawns & neighboring_files_bb(ksq) & ~dc; + b2 = rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S); + b1 &= b2; + if (!b1) + return mlist; // Direct checks, single pawn pushes - b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & empty; + Bitboard empty = pos.empty_squares(); + b2 = move_pawns(b1) & empty; b3 = b2 & pos.pawn_attacks(Them, ksq); while (b3) { @@ -767,9 +807,7 @@ 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); @@ -798,37 +836,51 @@ namespace { // Direct checks b = target & ~dc; - if (Piece == KING || !b) - return mlist; - - Bitboard checkSqs = pos.piece_attacks(ksq) & pos.empty_squares(); - while (b) + if (Piece != KING || b) { - Square from = pop_1st_bit(&b); - Bitboard bb = pos.piece_attacks(from) & checkSqs; - SERIALIZE_MOVES(bb); + 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 + template MoveStack* generate_pawn_blocking_evasions(const Position& pos, Bitboard pinned, Bitboard blockSquares, MoveStack* mlist) { + + // Calculate our parametrized parameters at compile time + const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); + const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); + 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); assert(pos.piece_on(to) == EMPTY); - if (square_rank(to) == TRANK_8) + if (square_rank(to) == TRank8BB) { (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN); (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK); @@ -839,8 +891,8 @@ 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);