X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovegen.cpp;h=1e42f99e91231da212cdf17cb473727853329d2a;hb=83eac08e7562d93787f75eccd4b7781c4bd45dd3;hp=b57f41a9829ed3264293418feff27736dbe68eec;hpb=fd8e88427b1268bfddc0b2ab72f639f758b7be0b;p=stockfish diff --git a/src/movegen.cpp b/src/movegen.cpp index b57f41a9..1e42f99e 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,8 +1,6 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file) Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -23,28 +21,28 @@ #include "movegen.h" #include "position.h" +namespace Stockfish { + namespace { template ExtMove* make_promotions(ExtMove* moveList, Square to, Square ksq) { if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS) + { *moveList++ = make(to - D, to, QUEEN); + if (attacks_bb(to) & ksq) + *moveList++ = make(to - D, to, KNIGHT); + } if (Type == QUIETS || Type == EVASIONS || Type == NON_EVASIONS) { *moveList++ = make(to - D, to, ROOK); *moveList++ = make(to - D, to, BISHOP); - *moveList++ = make(to - D, to, KNIGHT); + if (!(attacks_bb(to) & ksq)) + *moveList++ = make(to - D, to, KNIGHT); } - // Knight promotion is the only promotion that can give a direct check - // that's not already included in the queen promotion. - if (Type == QUIET_CHECKS && (attacks_bb(to) & ksq)) - *moveList++ = make(to - D, to, KNIGHT); - else - (void)ksq; // Silence a warning under MSVC - return moveList; } @@ -65,7 +63,7 @@ namespace { Bitboard pawnsOn7 = pos.pieces(Us, PAWN) & TRank7BB; Bitboard pawnsNotOn7 = pos.pieces(Us, PAWN) & ~TRank7BB; - Bitboard enemies = (Type == EVASIONS ? pos.pieces(Them) & target: + Bitboard enemies = (Type == EVASIONS ? pos.checkers(): Type == CAPTURES ? target : pos.pieces(Them)); // Single and double pawn pushes, no promotions @@ -89,7 +87,7 @@ namespace { // Add pawn pushes which give 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. Note that a possible discovery check + // don't generate captures. Note that a possible discovered check // promotion has been already generated amongst the captures. Bitboard dcCandidateQuiets = pos.blockers_for_king(Them) & pawnsNotOn7; if (dcCandidateQuiets) @@ -104,13 +102,13 @@ namespace { while (b1) { - Square to = pop_lsb(&b1); + Square to = pop_lsb(b1); *moveList++ = make_move(to - Up, to); } while (b2) { - Square to = pop_lsb(&b2); + Square to = pop_lsb(b2); *moveList++ = make_move(to - Up - Up, to); } } @@ -129,16 +127,16 @@ namespace { Bitboard b3 = shift(pawnsOn7) & emptySquares; while (b1) - moveList = make_promotions(moveList, pop_lsb(&b1), ksq); + moveList = make_promotions(moveList, pop_lsb(b1), ksq); while (b2) - moveList = make_promotions(moveList, pop_lsb(&b2), ksq); + moveList = make_promotions(moveList, pop_lsb(b2), ksq); while (b3) - moveList = make_promotions(moveList, pop_lsb(&b3), ksq); + moveList = make_promotions(moveList, pop_lsb(b3), ksq); } - // Standard and en-passant captures + // Standard and en passant captures if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS) { Bitboard b1 = shift(pawnsNotOn7) & enemies; @@ -146,13 +144,13 @@ namespace { while (b1) { - Square to = pop_lsb(&b1); + Square to = pop_lsb(b1); *moveList++ = make_move(to - UpRight, to); } while (b2) { - Square to = pop_lsb(&b2); + Square to = pop_lsb(b2); *moveList++ = make_move(to - UpLeft, to); } @@ -160,10 +158,8 @@ namespace { { assert(rank_of(pos.ep_square()) == relative_rank(Us, RANK_6)); - // An en passant capture can be an evasion only if the checking piece - // is the double pushed pawn and so is in the target. Otherwise this - // is a discovery check and we are forced to do otherwise. - if (Type == EVASIONS && !(target & (pos.ep_square() - Up))) + // An en passant capture cannot resolve a discovered check + if (Type == EVASIONS && (target & (pos.ep_square() + Up))) return moveList; b1 = pawnsNotOn7 & pawn_attacks_bb(Them, pos.ep_square()); @@ -171,7 +167,7 @@ namespace { assert(b1); while (b1) - *moveList++ = make(pop_lsb(&b1), pos.ep_square()); + *moveList++ = make(pop_lsb(b1), pos.ep_square()); } } @@ -179,32 +175,23 @@ namespace { } - template - ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard target) { + template + ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard piecesToMove, Bitboard target) { static_assert(Pt != KING && Pt != PAWN, "Unsupported piece type in generate_moves()"); - const Square* pl = pos.squares(Us); + Bitboard bb = piecesToMove & pos.pieces(Pt); - for (Square from = *pl; from != SQ_NONE; from = *++pl) + while (bb) { - if (Checks) - { - if ( (Pt == BISHOP || Pt == ROOK || Pt == QUEEN) - && !(attacks_bb(from) & target & pos.check_squares(Pt))) - continue; - - if (pos.blockers_for_king(~Us) & from) - continue; - } + Square from = pop_lsb(bb); Bitboard b = attacks_bb(from, pos.pieces()) & target; - - if (Checks) + if constexpr (Checks) b &= pos.check_squares(Pt); while (b) - *moveList++ = make_move(from, pop_lsb(&b)); + *moveList++ = make_move(from, pop_lsb(b)); } return moveList; @@ -213,8 +200,14 @@ namespace { template ExtMove* generate_all(const Position& pos, ExtMove* moveList) { - constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantations - Bitboard target; + + static_assert(Type != LEGAL, "Unsupported type in generate_all()"); + + constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantiations + Bitboard target, piecesToMove = pos.pieces(Us); + + if(Type == QUIET_CHECKS) + piecesToMove &= ~pos.blockers_for_king(~Us); switch (Type) { @@ -226,33 +219,28 @@ namespace { target = ~pos.pieces(); break; case EVASIONS: - { - Square checksq = lsb(pos.checkers()); - target = between_bb(pos.square(Us), checksq) | checksq; + target = between_bb(pos.square(Us), lsb(pos.checkers())); break; - } case NON_EVASIONS: target = ~pos.pieces(Us); break; - default: - static_assert(true, "Unsupported type in generate_all()"); } moveList = generate_pawn_moves(pos, moveList, target); - moveList = generate_moves(pos, moveList, target); - moveList = generate_moves(pos, moveList, target); - moveList = generate_moves(pos, moveList, target); - moveList = generate_moves(pos, moveList, target); + moveList = generate_moves(pos, moveList, piecesToMove, target); + moveList = generate_moves(pos, moveList, piecesToMove, target); + moveList = generate_moves< ROOK, Checks>(pos, moveList, piecesToMove, target); + moveList = generate_moves< QUEEN, Checks>(pos, moveList, piecesToMove, target); if (Type != QUIET_CHECKS && Type != EVASIONS) { Square ksq = pos.square(Us); Bitboard b = attacks_bb(ksq) & target; while (b) - *moveList++ = make_move(ksq, pop_lsb(&b)); + *moveList++ = make_move(ksq, pop_lsb(b)); if ((Type != CAPTURES) && pos.can_castle(Us & ANY_CASTLING)) - for(CastlingRights cr : { Us & KING_SIDE, Us & QUEEN_SIDE } ) + for (CastlingRights cr : { Us & KING_SIDE, Us & QUEEN_SIDE } ) if (!pos.castling_impeded(cr) && pos.can_castle(cr)) *moveList++ = make(ksq, pos.castling_rook_square(cr)); } @@ -263,8 +251,8 @@ namespace { } // namespace -/// Generates all pseudo-legal captures and queen promotions -/// Generates all pseudo-legal non-captures and underpromotions +/// Generates all pseudo-legal captures plus queen and checking knight promotions +/// Generates all pseudo-legal non-captures and underpromotions (except checking knight) /// Generates all pseudo-legal captures and non-captures /// /// Returns a pointer to the end of the move list. @@ -287,8 +275,8 @@ template ExtMove* generate(const Position&, ExtMove*); template ExtMove* generate(const Position&, ExtMove*); -/// generate generates all pseudo-legal non-captures and knight -/// underpromotions that give check. Returns a pointer to the end of the move list. +/// generate generates all pseudo-legal non-captures giving check, +/// except castling. Returns a pointer to the end of the move list. template<> ExtMove* generate(const Position& pos, ExtMove* moveList) { @@ -299,7 +287,7 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { while (dc) { - Square from = pop_lsb(&dc); + Square from = pop_lsb(dc); PieceType pt = type_of(pos.piece_on(from)); Bitboard b = attacks_bb(pt, from, pos.pieces()) & ~pos.pieces(); @@ -308,7 +296,7 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { b &= ~attacks_bb(pos.square(~us)); while (b) - *moveList++ = make_move(from, pop_lsb(&b)); + *moveList++ = make_move(from, pop_lsb(b)); } return us == WHITE ? generate_all(pos, moveList) @@ -332,17 +320,17 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { // the king evasions in order to skip known illegal moves, which avoids any // useless legality checks later on. while (sliders) - sliderAttacks |= LineBB[ksq][pop_lsb(&sliders)] & ~pos.checkers(); + sliderAttacks |= line_bb(ksq, pop_lsb(sliders)) & ~pos.checkers(); // Generate evasions for king, capture and non capture moves Bitboard b = attacks_bb(ksq) & ~pos.pieces(us) & ~sliderAttacks; while (b) - *moveList++ = make_move(ksq, pop_lsb(&b)); + *moveList++ = make_move(ksq, pop_lsb(b)); if (more_than_one(pos.checkers())) return moveList; // Double check, only a king move can save the day - // Generate blocking evasions or captures of the checking piece + // Generate blocking interpositions or captures of the checking piece return us == WHITE ? generate_all(pos, moveList) : generate_all(pos, moveList); } @@ -361,7 +349,7 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { moveList = pos.checkers() ? generate(pos, moveList) : generate(pos, moveList); while (cur != moveList) - if ( (pinned || from_sq(*cur) == ksq || type_of(*cur) == ENPASSANT) + if ( ((pinned && pinned & from_sq(*cur)) || from_sq(*cur) == ksq || type_of(*cur) == EN_PASSANT) && !pos.legal(*cur)) *cur = (--moveList)->move; else @@ -369,3 +357,5 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { return moveList; } + +} // namespace Stockfish