X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovegen.cpp;h=5049613617ac5eb304385fa82f40fc073dbed66f;hb=c489df6f5b5629a135af3b8222fa1ef607ec1526;hp=3340f65cf10479113d7228d2fbe461dde3e282f4;hpb=5f1843c9cb55afcd3fb1da9e9dc4b0092f25d9f0;p=stockfish diff --git a/src/movegen.cpp b/src/movegen.cpp index 3340f65c..50496136 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,6 +1,6 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file) + 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 @@ -21,6 +21,8 @@ #include "movegen.h" #include "position.h" +namespace Stockfish { + namespace { template @@ -61,7 +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 @@ -85,7 +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) @@ -100,13 +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); } } @@ -125,16 +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; @@ -142,13 +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); } @@ -156,10 +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()); @@ -167,7 +167,7 @@ namespace { assert(b1); while (b1) - *moveList++ = make(pop_lsb(&b1), pos.ep_square()); + *moveList++ = make(pop_lsb(b1), pos.ep_square()); } } @@ -175,32 +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; @@ -209,8 +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) { @@ -222,30 +219,25 @@ 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 } ) @@ -260,7 +252,7 @@ namespace { /// 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 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. @@ -283,8 +275,8 @@ template ExtMove* generate(const Position&, ExtMove*); template ExtMove* generate(const Position&, ExtMove*); -/// generate generates all pseudo-legal non-captures. -/// 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) { @@ -295,7 +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(); @@ -304,7 +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) @@ -321,24 +313,16 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { Color us = pos.side_to_move(); Square ksq = pos.square(us); - Bitboard sliderAttacks = 0; - Bitboard sliders = pos.checkers() & ~pos.pieces(KNIGHT, PAWN); - - // Find all the squares attacked by slider checkers. We will remove them from - // the king evasions in order to skip known illegal moves, which avoids any - // useless legality checks later on. - while (sliders) - 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; + // Generate evasions for king + Bitboard b = attacks_bb(ksq) & ~pos.pieces(us); 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); } @@ -357,7 +341,7 @@ 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 @@ -365,3 +349,5 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) { return moveList; } + +} // namespace Stockfish