X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=0b91582ec997461b38233770b40339a69164d87d;hp=cb221d95e178e1833c00fb414e183561b02a9924;hb=83ecfa7c33ab3e89fcbc506f0f4d5312baa26aeb;hpb=ad2a0e356e395038a08324f9ff0afee7fc98b8e9 diff --git a/src/movegen.cpp b/src/movegen.cpp index cb221d95..0b91582e 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -2,7 +2,7 @@ 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) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -25,46 +25,6 @@ namespace { - template - ExtMove* generate_castling(const Position& pos, ExtMove* moveList, Color us) { - - static const bool KingSide = (Cr == WHITE_OO || Cr == BLACK_OO); - - 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.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 Direction K = Chess960 ? kto > kfrom ? WEST : EAST - : KingSide ? WEST : EAST; - - for (Square s = kto; s != kfrom; s += K) - if (pos.attackers_to(s) & enemies) - 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 moveList; - - Move m = make(kfrom, rfrom); - - if (Checks && !pos.gives_check(m)) - return moveList; - - *moveList++ = m; - return moveList; - } - - template ExtMove* make_promotions(ExtMove* moveList, Square to, Square ksq) { @@ -92,16 +52,15 @@ namespace { template 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 Direction Up = (Us == WHITE ? NORTH : SOUTH); - const Direction UpRight = (Us == WHITE ? NORTH_EAST : SOUTH_WEST); - const Direction UpLeft = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); + // Compute some compile time parameters relative to the white side + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + constexpr Direction Up = pawn_push(Us); + constexpr Direction UpRight = (Us == WHITE ? NORTH_EAST : SOUTH_WEST); + constexpr Direction UpLeft = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); + const Square ksq = pos.square(Them); Bitboard emptySquares; Bitboard pawnsOn7 = pos.pieces(Us, PAWN) & TRank7BB; @@ -126,8 +85,6 @@ namespace { if (Type == QUIET_CHECKS) { - Square ksq = pos.square(Them); - b1 &= pos.attacks_from(ksq, Them); b2 &= pos.attacks_from(ksq, Them); @@ -135,10 +92,10 @@ namespace { // 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 amongst the captures. - Bitboard dcCandidates = pos.blockers_for_king(Them); - if (pawnsNotOn7 & dcCandidates) + Bitboard dcCandidateQuiets = pos.blockers_for_king(Them) & pawnsNotOn7; + if (dcCandidateQuiets) { - Bitboard dc1 = shift(pawnsNotOn7 & dcCandidates) & emptySquares & ~file_bb(ksq); + Bitboard dc1 = shift(dcCandidateQuiets) & emptySquares & ~file_bb(ksq); Bitboard dc2 = shift(dc1 & TRank3BB) & emptySquares; b1 |= dc1; @@ -160,7 +117,7 @@ namespace { } // Promotions and underpromotions - if (pawnsOn7 && (Type != EVASIONS || (target & TRank8BB))) + if (pawnsOn7) { if (Type == CAPTURES) emptySquares = ~pos.pieces(); @@ -172,8 +129,6 @@ namespace { 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); @@ -229,7 +184,7 @@ namespace { ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Color us, Bitboard target) { - assert(Pt != KING && Pt != PAWN); + static_assert(Pt != KING && Pt != PAWN, "Unsupported piece type in generate_moves()"); const Square* pl = pos.squares(us); @@ -261,7 +216,9 @@ namespace { template ExtMove* generate_all(const Position& pos, ExtMove* moveList, Bitboard target) { - const bool Checks = Type == QUIET_CHECKS; + constexpr CastlingRights OO = Us & KING_SIDE; + constexpr CastlingRights OOO = Us & QUEEN_SIDE; + constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantations moveList = generate_pawn_moves(pos, moveList, target); moveList = generate_moves(pos, moveList, Us, target); @@ -275,19 +232,14 @@ namespace { 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 (pos.is_chess960()) - { - moveList = generate_castling::right, Checks, true>(pos, moveList, Us); - moveList = generate_castling::right, Checks, true>(pos, moveList, Us); - } - else + if (Type != CAPTURES && pos.can_castle(CastlingRights(OO | OOO))) { - moveList = generate_castling::right, Checks, false>(pos, moveList, Us); - moveList = generate_castling::right, Checks, false>(pos, moveList, Us); + if (!pos.castling_impeded(OO) && pos.can_castle(OO)) + *moveList++ = make(ksq, pos.castling_rook_square(OO)); + + if (!pos.castling_impeded(OOO) && pos.can_castle(OOO)) + *moveList++ = make(ksq, pos.castling_rook_square(OOO)); } } @@ -297,19 +249,16 @@ namespace { } // namespace -/// generate generates all pseudo-legal captures and queen -/// promotions. Returns a pointer to the end of the move list. -/// -/// generate generates all pseudo-legal non-captures and -/// underpromotions. Returns a pointer to the end of the move list. +/// Generates all pseudo-legal captures and queen promotions +/// Generates all pseudo-legal non-captures and underpromotions +/// Generates all pseudo-legal captures and non-captures /// -/// generate generates all pseudo-legal captures and -/// non-captures. Returns a pointer to the end of the move list. +/// Returns a pointer to the end of the move list. template ExtMove* generate(const Position& pos, ExtMove* moveList) { - assert(Type == CAPTURES || Type == QUIETS || Type == NON_EVASIONS); + static_assert(Type == CAPTURES || Type == QUIETS || Type == NON_EVASIONS, "Unsupported type in generate()"); assert(!pos.checkers()); Color us = pos.side_to_move();