X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=e7678979f42450029c78d70cb0afe0d01358139e;hp=a3623a69e5e4369bfcfcae701e04cdce4c2d82d0;hb=e2d3c163cbdd98de6f0399db358be964d014d313;hpb=9763c69fa5683accd7e81786977be4b195370a7b diff --git a/src/movegen.cpp b/src/movegen.cpp index a3623a69..e7678979 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,7 +1,8 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -22,99 +23,86 @@ #include "movegen.h" #include "position.h" -/// Simple macro to wrap a very common while loop, no facny, no flexibility, -/// hardcoded names 'mlist' and 'from'. -#define SERIALIZE(b) while (b) (mlist++)->move = make_move(from, pop_lsb(&b)) - -/// Version used for pawns, where the 'from' square is given as a delta from the 'to' square -#define SERIALIZE_PAWNS(b, d) while (b) { Square to = pop_lsb(&b); \ - (mlist++)->move = make_move(to - (d), to); } namespace { - template - ExtMove* generate_castle(const Position& pos, ExtMove* mlist, Color us) { + template + ExtMove* generate_castling(const Position& pos, ExtMove* moveList) { + + constexpr CastlingRight Cr = Us | Cs; + constexpr bool KingSide = (Cs == KING_SIDE); - if (pos.castle_impeded(us, Side) || !pos.can_castle(make_castle_right(us, Side))) - return mlist; + if (pos.castling_impeded(Cr) || !pos.can_castle(Cr)) + return moveList; // After castling, the rook and king final positions are the same in Chess960 // as they would be in standard chess. - Square kfrom = pos.king_square(us); - Square rfrom = pos.castle_rook_square(us, Side); - Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1); - Bitboard enemies = pos.pieces(~us); + Square kfrom = pos.square(Us); + Square rfrom = pos.castling_rook_square(Cr); + Square kto = relative_square(Us, KingSide ? SQ_G1 : SQ_C1); + Bitboard enemies = pos.pieces(~Us); assert(!pos.checkers()); - const int K = Chess960 ? kto > kfrom ? -1 : 1 - : Side == KING_SIDE ? -1 : 1; + const Direction step = Chess960 ? kto > kfrom ? WEST : EAST + : KingSide ? WEST : EAST; - for (Square s = kto; s != kfrom; s += (Square)K) + for (Square s = kto; s != kfrom; s += step) if (pos.attackers_to(s) & enemies) - return mlist; + return moveList; // Because we generate only legal castling moves we need to verify that // when moving the castling rook we do not discover some hidden checker. // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1. - if (Chess960 && (attacks_bb(kto, pos.pieces() ^ rfrom) & pos.pieces(~us, ROOK, QUEEN))) - return mlist; + if (Chess960 && (attacks_bb(kto, pos.pieces() ^ rfrom) & pos.pieces(~Us, ROOK, QUEEN))) + return moveList; - (mlist++)->move = make(kfrom, rfrom); + Move m = make(kfrom, rfrom); - if (Checks && !pos.gives_check((mlist - 1)->move, CheckInfo(pos))) - --mlist; + if (Checks && !pos.gives_check(m)) + return moveList; - return mlist; + *moveList++ = m; + return moveList; } - template - inline ExtMove* generate_promotions(ExtMove* mlist, Bitboard pawnsOn7, - Bitboard target, const CheckInfo* ci) { + template + ExtMove* make_promotions(ExtMove* moveList, Square to, Square ksq) { - Bitboard b = shift_bb(pawnsOn7) & target; + if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS) + *moveList++ = make(to - D, to, QUEEN); - while (b) + if (Type == QUIETS || Type == EVASIONS || Type == NON_EVASIONS) { - Square to = pop_lsb(&b); - - if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS) - (mlist++)->move = make(to - Delta, to, QUEEN); - - if (Type == QUIETS || Type == EVASIONS || Type == NON_EVASIONS) - { - (mlist++)->move = make(to - Delta, to, ROOK); - (mlist++)->move = make(to - Delta, to, BISHOP); - (mlist++)->move = make(to - Delta, to, KNIGHT); - } - - // Knight-promotion is the only one that can give a direct check not - // already included in the queen-promotion. - if (Type == QUIET_CHECKS && (StepAttacksBB[W_KNIGHT][to] & ci->ksq)) - (mlist++)->move = make(to - Delta, to, KNIGHT); - else - (void)ci; // Silence a warning under MSVC + *moveList++ = make(to - D, to, ROOK); + *moveList++ = make(to - D, to, BISHOP); + *moveList++ = make(to - D, to, KNIGHT); } - return mlist; + // 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 && (PseudoAttacks[KNIGHT][to] & ksq)) + *moveList++ = make(to - D, to, KNIGHT); + else + (void)ksq; // Silence a warning under MSVC + + return moveList; } template - ExtMove* generate_pawn_moves(const Position& pos, ExtMove* mlist, - Bitboard target, const CheckInfo* ci) { + ExtMove* generate_pawn_moves(const Position& pos, ExtMove* moveList, Bitboard target) { // Compute 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 TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB); - const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); - const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - const Square Up = (Us == WHITE ? DELTA_N : DELTA_S); - const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW); - const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Direction UpRight = (Us == WHITE ? NORTH_EAST : SOUTH_WEST); + constexpr Direction UpLeft = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); - Bitboard b1, b2, dc1, dc2, emptySquares; + Bitboard emptySquares; Bitboard pawnsOn7 = pos.pieces(Us, PAWN) & TRank7BB; Bitboard pawnsNotOn7 = pos.pieces(Us, PAWN) & ~TRank7BB; @@ -127,8 +115,8 @@ namespace { { emptySquares = (Type == QUIETS || Type == QUIET_CHECKS ? target : ~pos.pieces()); - b1 = shift_bb(pawnsNotOn7) & emptySquares; - b2 = shift_bb(b1 & TRank3BB) & emptySquares; + Bitboard b1 = shift(pawnsNotOn7) & emptySquares; + Bitboard b2 = shift(b1 & TRank3BB) & emptySquares; if (Type == EVASIONS) // Consider only blocking squares { @@ -138,29 +126,41 @@ namespace { if (Type == QUIET_CHECKS) { - b1 &= pos.attacks_from(ci->ksq, Them); - b2 &= pos.attacks_from(ci->ksq, Them); + Square ksq = pos.square(Them); + + b1 &= pos.attacks_from(ksq, Them); + b2 &= pos.attacks_from(ksq, Them); // 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 - // promotion has been already generated among captures. - if (pawnsNotOn7 & ci->dcCandidates) + // promotion has been already generated amongst the captures. + Bitboard dcCandidates = pos.blockers_for_king(Them); + if (pawnsNotOn7 & dcCandidates) { - dc1 = shift_bb(pawnsNotOn7 & ci->dcCandidates) & emptySquares & ~file_bb(ci->ksq); - dc2 = shift_bb(dc1 & TRank3BB) & emptySquares; + Bitboard dc1 = shift(pawnsNotOn7 & dcCandidates) & emptySquares & ~file_bb(ksq); + Bitboard dc2 = shift(dc1 & TRank3BB) & emptySquares; b1 |= dc1; b2 |= dc2; } } - SERIALIZE_PAWNS(b1, Up); - SERIALIZE_PAWNS(b2, Up + Up); + while (b1) + { + Square to = pop_lsb(&b1); + *moveList++ = make_move(to - Up, to); + } + + while (b2) + { + Square to = pop_lsb(&b2); + *moveList++ = make_move(to - Up - Up, to); + } } // Promotions and underpromotions - if (pawnsOn7 && (Type != EVASIONS || (target & TRank8BB))) + if (pawnsOn7) { if (Type == CAPTURES) emptySquares = ~pos.pieces(); @@ -168,19 +168,39 @@ namespace { if (Type == EVASIONS) emptySquares &= target; - mlist = generate_promotions(mlist, pawnsOn7, enemies, ci); - mlist = generate_promotions(mlist, pawnsOn7, enemies, ci); - mlist = generate_promotions(mlist, pawnsOn7, emptySquares, ci); + Bitboard b1 = shift(pawnsOn7) & enemies; + Bitboard b2 = shift(pawnsOn7) & enemies; + Bitboard b3 = shift(pawnsOn7) & emptySquares; + + Square ksq = pos.square(Them); + + while (b1) + moveList = make_promotions(moveList, pop_lsb(&b1), ksq); + + while (b2) + moveList = make_promotions(moveList, pop_lsb(&b2), ksq); + + while (b3) + moveList = make_promotions(moveList, pop_lsb(&b3), ksq); } // Standard and en-passant captures if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS) { - b1 = shift_bb(pawnsNotOn7) & enemies; - b2 = shift_bb(pawnsNotOn7) & enemies; + Bitboard b1 = shift(pawnsNotOn7) & enemies; + Bitboard b2 = shift(pawnsNotOn7) & enemies; - SERIALIZE_PAWNS(b1, Right); - SERIALIZE_PAWNS(b2, Left); + while (b1) + { + Square to = pop_lsb(&b1); + *moveList++ = make_move(to - UpRight, to); + } + + while (b2) + { + Square to = pop_lsb(&b2); + *moveList++ = make_move(to - UpLeft, to); + } if (pos.ep_square() != SQ_NONE) { @@ -190,90 +210,90 @@ namespace { // 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))) - return mlist; + return moveList; b1 = pawnsNotOn7 & pos.attacks_from(pos.ep_square(), Them); assert(b1); while (b1) - (mlist++)->move = make(pop_lsb(&b1), pos.ep_square()); + *moveList++ = make(pop_lsb(&b1), pos.ep_square()); } } - return mlist; + return moveList; } - template FORCE_INLINE - ExtMove* generate_moves(const Position& pos, ExtMove* mlist, Color us, - Bitboard target, const CheckInfo* ci) { + template + ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Color us, + Bitboard target) { assert(Pt != KING && Pt != PAWN); - const Square* pl = pos.list(us); + const Square* pl = pos.squares(us); for (Square from = *pl; from != SQ_NONE; from = *++pl) { if (Checks) { if ( (Pt == BISHOP || Pt == ROOK || Pt == QUEEN) - && !(PseudoAttacks[Pt][from] & target & ci->checkSq[Pt])) + && !(PseudoAttacks[Pt][from] & target & pos.check_squares(Pt))) continue; - if (unlikely(ci->dcCandidates) && (ci->dcCandidates & from)) + if (pos.blockers_for_king(~us) & from) continue; } Bitboard b = pos.attacks_from(from) & target; if (Checks) - b &= ci->checkSq[Pt]; + b &= pos.check_squares(Pt); - SERIALIZE(b); + while (b) + *moveList++ = make_move(from, pop_lsb(&b)); } - return mlist; + return moveList; } - template FORCE_INLINE - ExtMove* generate_all(const Position& pos, ExtMove* mlist, Bitboard target, - const CheckInfo* ci = NULL) { + template + ExtMove* generate_all(const Position& pos, ExtMove* moveList, Bitboard target) { - const bool Checks = Type == QUIET_CHECKS; + constexpr bool Checks = Type == QUIET_CHECKS; - mlist = generate_pawn_moves(pos, mlist, target, ci); - mlist = generate_moves(pos, mlist, Us, target, ci); - mlist = generate_moves(pos, mlist, Us, target, ci); - mlist = generate_moves< ROOK, Checks>(pos, mlist, Us, target, ci); - mlist = generate_moves< QUEEN, Checks>(pos, mlist, Us, target, ci); + moveList = generate_pawn_moves(pos, moveList, target); + moveList = generate_moves(pos, moveList, Us, target); + moveList = generate_moves(pos, moveList, Us, target); + moveList = generate_moves< ROOK, Checks>(pos, moveList, Us, target); + moveList = generate_moves< QUEEN, Checks>(pos, moveList, Us, target); if (Type != QUIET_CHECKS && Type != EVASIONS) { - Square from = pos.king_square(Us); - Bitboard b = pos.attacks_from(from) & target; - SERIALIZE(b); + Square ksq = pos.square(Us); + Bitboard b = pos.attacks_from(ksq) & target; + while (b) + *moveList++ = make_move(ksq, pop_lsb(&b)); } - if (Type != CAPTURES && Type != EVASIONS && pos.can_castle(Us)) + if (Type != CAPTURES && Type != EVASIONS && pos.castling_rights(Us)) { if (pos.is_chess960()) { - mlist = generate_castle< KING_SIDE, Checks, true>(pos, mlist, Us); - mlist = generate_castle(pos, mlist, Us); + moveList = generate_castling(pos, moveList); + moveList = generate_castling(pos, moveList); } else { - mlist = generate_castle< KING_SIDE, Checks, false>(pos, mlist, Us); - mlist = generate_castle(pos, mlist, Us); + moveList = generate_castling(pos, moveList); + moveList = generate_castling(pos, moveList); } } - return mlist; + return moveList; } - } // namespace @@ -287,19 +307,19 @@ namespace { /// non-captures. Returns a pointer to the end of the move list. template -ExtMove* generate(const Position& pos, ExtMove* mlist) { +ExtMove* generate(const Position& pos, ExtMove* moveList) { assert(Type == CAPTURES || Type == QUIETS || Type == NON_EVASIONS); assert(!pos.checkers()); Color us = pos.side_to_move(); - Bitboard target = Type == CAPTURES ? pos.pieces(~us) - : Type == QUIETS ? ~pos.pieces() - : Type == NON_EVASIONS ? ~pos.pieces(us) : 0; + Bitboard target = Type == CAPTURES ? pos.pieces(~us) + : Type == QUIETS ? ~pos.pieces() + : Type == NON_EVASIONS ? ~pos.pieces(us) : 0; - return us == WHITE ? generate_all(pos, mlist, target) - : generate_all(pos, mlist, target); + return us == WHITE ? generate_all(pos, moveList, target) + : generate_all(pos, moveList, target); } // Explicit template instantiations @@ -311,13 +331,12 @@ 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. template<> -ExtMove* generate(const Position& pos, ExtMove* mlist) { +ExtMove* generate(const Position& pos, ExtMove* moveList) { assert(!pos.checkers()); Color us = pos.side_to_move(); - CheckInfo ci(pos); - Bitboard dc = ci.dcCandidates; + Bitboard dc = pos.blockers_for_king(~us) & pos.pieces(us); while (dc) { @@ -325,82 +344,78 @@ ExtMove* generate(const Position& pos, ExtMove* mlist) { PieceType pt = type_of(pos.piece_on(from)); if (pt == PAWN) - continue; // Will be generated togheter with direct checks + continue; // Will be generated together with direct checks - Bitboard b = pos.attacks_from(Piece(pt), from) & ~pos.pieces(); + Bitboard b = pos.attacks_from(pt, from) & ~pos.pieces(); if (pt == KING) - b &= ~PseudoAttacks[QUEEN][ci.ksq]; + b &= ~PseudoAttacks[QUEEN][pos.square(~us)]; - SERIALIZE(b); + while (b) + *moveList++ = make_move(from, pop_lsb(&b)); } - return us == WHITE ? generate_all(pos, mlist, ~pos.pieces(), &ci) - : generate_all(pos, mlist, ~pos.pieces(), &ci); + return us == WHITE ? generate_all(pos, moveList, ~pos.pieces()) + : generate_all(pos, moveList, ~pos.pieces()); } /// generate generates all pseudo-legal check evasions when the side /// to move is in check. Returns a pointer to the end of the move list. template<> -ExtMove* generate(const Position& pos, ExtMove* mlist) { +ExtMove* generate(const Position& pos, ExtMove* moveList) { assert(pos.checkers()); - int checkersCnt = 0; Color us = pos.side_to_move(); - Square ksq = pos.king_square(us), from = ksq /* For SERIALIZE */, checksq; + Square ksq = pos.square(us); Bitboard sliderAttacks = 0; - Bitboard b = pos.checkers(); + Bitboard sliders = pos.checkers() & ~pos.pieces(KNIGHT, PAWN); - assert(pos.checkers()); - - // Find squares attacked by slider checkers, we will remove them from the king - // evasions so to skip known illegal moves avoiding useless legality check later. - do + // 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) { - ++checkersCnt; - checksq = pop_lsb(&b); - - assert(color_of(pos.piece_on(checksq)) == ~us); - - if (type_of(pos.piece_on(checksq)) > KNIGHT) // A slider - sliderAttacks |= LineBB[checksq][ksq] ^ checksq; - - } while (b); + Square checksq = pop_lsb(&sliders); + sliderAttacks |= LineBB[checksq][ksq] ^ checksq; + } // Generate evasions for king, capture and non capture moves - b = pos.attacks_from(ksq) & ~pos.pieces(us) & ~sliderAttacks; - SERIALIZE(b); + Bitboard b = pos.attacks_from(ksq) & ~pos.pieces(us) & ~sliderAttacks; + while (b) + *moveList++ = make_move(ksq, pop_lsb(&b)); - if (checkersCnt > 1) - return mlist; // Double check, only a king move can save the day + 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 + Square checksq = lsb(pos.checkers()); Bitboard target = between_bb(checksq, ksq) | checksq; - return us == WHITE ? generate_all(pos, mlist, target) - : generate_all(pos, mlist, target); + return us == WHITE ? generate_all(pos, moveList, target) + : generate_all(pos, moveList, target); } /// generate generates all the legal moves in the given position template<> -ExtMove* generate(const Position& pos, ExtMove* mlist) { - - ExtMove *end, *cur = mlist; - Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); - Square ksq = pos.king_square(pos.side_to_move()); - - end = pos.checkers() ? generate(pos, mlist) - : generate(pos, mlist); - while (cur != end) - if ( (pinned || from_sq(cur->move) == ksq || type_of(cur->move) == ENPASSANT) - && !pos.legal(cur->move, pinned)) - cur->move = (--end)->move; +ExtMove* generate(const Position& pos, ExtMove* moveList) { + + Color us = pos.side_to_move(); + Bitboard pinned = pos.blockers_for_king(us) & pos.pieces(us); + Square ksq = pos.square(us); + ExtMove* cur = moveList; + + moveList = pos.checkers() ? generate(pos, moveList) + : generate(pos, moveList); + while (cur != moveList) + if ( (pinned || from_sq(*cur) == ksq || type_of(*cur) == ENPASSANT) + && !pos.legal(*cur)) + *cur = (--moveList)->move; else ++cur; - return end; + return moveList; }