X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovegen.cpp;h=1082ad016aab60bbe60c7a782113b38920e7efb5;hp=9b4cc130b2268fb0e6029b9bf2b547741ac46bf9;hb=67338e6f322b8f8ec0d897815e16a87937efc9b0;hpb=e5077dc11e8047eb8ce32a166a73e433a7e19b15 diff --git a/src/movegen.cpp b/src/movegen.cpp index 9b4cc130..1082ad01 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, 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 @@ -18,9 +18,11 @@ */ #include +#include #include "bitcount.h" #include "movegen.h" +#include "position.h" // Simple macro to wrap a very common while loop, no facny, no flexibility, // hardcoded list name 'mlist' and from square 'from'. @@ -45,14 +47,13 @@ namespace { template inline MoveStack* generate_discovered_checks(const Position& pos, MoveStack* mlist, Square from) { - assert(Pt != QUEEN); + assert(Pt != QUEEN && Pt != PAWN); Bitboard b = pos.attacks_from(from) & pos.empty_squares(); + if (Pt == KING) - { - Square ksq = pos.king_square(opposite_color(pos.side_to_move())); - b &= ~QueenPseudoAttacks[ksq]; - } + b &= ~QueenPseudoAttacks[pos.king_square(flip(pos.side_to_move()))]; + SERIALIZE_MOVES(b); return mlist; } @@ -60,13 +61,13 @@ namespace { template inline MoveStack* generate_direct_checks(const Position& pos, MoveStack* mlist, Color us, Bitboard dc, Square ksq) { - assert(Pt != KING); + assert(Pt != KING && Pt != PAWN); Bitboard checkSqs, b; Square from; - const Square* ptr = pos.piece_list_begin(us, Pt); + const Square* pl = pos.piece_list(us, Pt); - if ((from = *ptr++) == SQ_NONE) + if ((from = *pl++) == SQ_NONE) return mlist; checkSqs = pos.attacks_from(ksq) & pos.empty_squares(); @@ -84,7 +85,7 @@ namespace { b = pos.attacks_from(from) & checkSqs; SERIALIZE_MOVES(b); - } while ((from = *ptr++) != SQ_NONE); + } while ((from = *pl++) != SQ_NONE); return mlist; } @@ -111,15 +112,15 @@ namespace { Bitboard b; Square from; - const Square* ptr = pos.piece_list_begin(us, Pt); + const Square* pl = pos.piece_list(us, Pt); - if (*ptr != SQ_NONE) + if (*pl != SQ_NONE) { do { - from = *ptr; + from = *pl; b = pos.attacks_from(from) & target; SERIALIZE_MOVES(b); - } while (*++ptr != SQ_NONE); + } while (*++pl != SQ_NONE); } return mlist; } @@ -150,14 +151,13 @@ namespace { template MoveStack* generate(const Position& pos, MoveStack* mlist) { - assert(pos.is_ok()); assert(!pos.in_check()); Color us = pos.side_to_move(); Bitboard target; if (Type == MV_CAPTURE || Type == MV_NON_EVASION) - target = pos.pieces(opposite_color(us)); + target = pos.pieces(flip(us)); else if (Type == MV_NON_CAPTURE) target = pos.empty_squares(); else @@ -196,28 +196,27 @@ template MoveStack* generate(const Position& pos, MoveStack* mli template MoveStack* generate(const Position& pos, MoveStack* mlist); -/// generate_non_capture_checks() generates all pseudo-legal non-captures and knight +/// generate generates all pseudo-legal non-captures and knight /// underpromotions that give check. Returns a pointer to the end of the move list. template<> MoveStack* generate(const Position& pos, MoveStack* mlist) { - assert(pos.is_ok()); assert(!pos.in_check()); Bitboard b, dc; Square from; Color us = pos.side_to_move(); - Square ksq = pos.king_square(opposite_color(us)); + Square ksq = pos.king_square(flip(us)); - assert(pos.piece_on(ksq) == make_piece(opposite_color(us), KING)); + assert(pos.piece_on(ksq) == make_piece(flip(us), KING)); // Discovered non-capture checks - b = dc = pos.discovered_check_candidates(us); + b = dc = pos.discovered_check_candidates(); while (b) { from = pop_1st_bit(&b); - switch (piece_type(pos.piece_on(from))) + switch (type_of(pos.piece_on(from))) { case PAWN: /* Will be generated togheter with pawns direct checks */ break; case KNIGHT: mlist = generate_discovered_checks(pos, mlist, from); break; @@ -237,12 +236,11 @@ MoveStack* generate(const Position& pos, MoveStack* mlist) } -/// generate_evasions() generates all pseudo-legal check evasions when -/// the side to move is in check. Returns a pointer to the end of the move list. +/// 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<> MoveStack* generate(const Position& pos, MoveStack* mlist) { - assert(pos.is_ok()); assert(pos.in_check()); Bitboard b, target; @@ -251,7 +249,7 @@ MoveStack* generate(const Position& pos, MoveStack* mlist) { Color us = pos.side_to_move(); Square ksq = pos.king_square(us); Bitboard checkers = pos.checkers(); - Bitboard sliderAttacks = EmptyBoardBB; + Bitboard sliderAttacks = 0; assert(pos.piece_on(ksq) == make_piece(us, KING)); assert(checkers); @@ -265,9 +263,9 @@ MoveStack* generate(const Position& pos, MoveStack* mlist) { checkersCnt++; checksq = pop_1st_bit(&b); - assert(piece_color(pos.piece_on(checksq)) == opposite_color(us)); + assert(color_of(pos.piece_on(checksq)) == flip(us)); - switch (piece_type(pos.piece_on(checksq))) + switch (type_of(pos.piece_on(checksq))) { case BISHOP: sliderAttacks |= BishopPseudoAttacks[checksq]; break; case ROOK: sliderAttacks |= RookPseudoAttacks[checksq]; break; @@ -314,10 +312,8 @@ MoveStack* generate(const Position& pos, MoveStack* mlist) { template<> MoveStack* generate(const Position& pos, MoveStack* mlist) { - assert(pos.is_ok()); - MoveStack *last, *cur = mlist; - Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); + Bitboard pinned = pos.pinned_pieces(); last = pos.in_check() ? generate(pos, mlist) : generate(pos, mlist); @@ -357,7 +353,7 @@ namespace { return mlist; } - template + template inline MoveStack* generate_promotions(const Position& pos, MoveStack* mlist, Bitboard pawnsOn7, Bitboard target) { const Bitboard TFileABB = (Delta == DELTA_NE || Delta == DELTA_SE ? FileABB : FileHBB); @@ -376,20 +372,20 @@ namespace { to = pop_1st_bit(&b); if (Type == MV_CAPTURE || Type == MV_EVASION) - (*mlist++).move = make_promotion_move(to - Delta, to, QUEEN); + (*mlist++).move = make_promotion(to - Delta, to, QUEEN); if (Type == MV_NON_CAPTURE || Type == MV_EVASION) { - (*mlist++).move = make_promotion_move(to - Delta, to, ROOK); - (*mlist++).move = make_promotion_move(to - Delta, to, BISHOP); - (*mlist++).move = make_promotion_move(to - Delta, to, KNIGHT); + (*mlist++).move = make_promotion(to - Delta, to, ROOK); + (*mlist++).move = make_promotion(to - Delta, to, BISHOP); + (*mlist++).move = make_promotion(to - Delta, to, KNIGHT); } // This is the only possible under promotion that can give a check // not already included in the queen-promotion. if ( Type == MV_CHECK - && bit_is_set(pos.attacks_from(to), pos.king_square(opposite_color(Us)))) - (*mlist++).move = make_promotion_move(to - Delta, to, KNIGHT); + && bit_is_set(pos.attacks_from(to), pos.king_square(Delta > 0 ? BLACK : WHITE))) + (*mlist++).move = make_promotion(to - Delta, to, KNIGHT); else (void)pos; // Silence a warning under MSVC } return mlist; @@ -403,9 +399,9 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - const Square TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S); - const Square TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE); - const Square TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW); + const Square UP = (Us == WHITE ? DELTA_N : DELTA_S); + const Square RIGHT_UP = (Us == WHITE ? DELTA_NE : DELTA_SW); + const Square LEFT_UP = (Us == WHITE ? DELTA_NW : DELTA_SE); Square to; Bitboard b1, b2, dc1, dc2, pawnPushes, emptySquares; @@ -417,7 +413,7 @@ namespace { if (Type != MV_CAPTURE) { emptySquares = (Type == MV_NON_CAPTURE ? target : pos.empty_squares()); - pawnPushes = move_pawns(pawns & ~TRank7BB) & emptySquares; + pawnPushes = move_pawns(pawns & ~TRank7BB) & emptySquares; } if (Type == MV_EVASION) @@ -433,23 +429,23 @@ namespace { emptySquares = pos.empty_squares(); pawns &= ~TRank7BB; - mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); - mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); - mlist = generate_promotions(pos, mlist, pawnsOn7, emptySquares); + mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); + mlist = generate_promotions(pos, mlist, pawnsOn7, enemyPieces); + mlist = generate_promotions(pos, mlist, pawnsOn7, emptySquares); } // Standard captures if (Type == MV_CAPTURE || Type == MV_EVASION) { - mlist = generate_pawn_captures(mlist, pawns, enemyPieces); - mlist = generate_pawn_captures(mlist, pawns, enemyPieces); + mlist = generate_pawn_captures(mlist, pawns, enemyPieces); + mlist = generate_pawn_captures(mlist, pawns, enemyPieces); } // Single and double pawn pushes if (Type != MV_CAPTURE) { b1 = (Type != MV_EVASION ? pawnPushes : pawnPushes & emptySquares); - b2 = move_pawns(pawnPushes & TRank3BB) & emptySquares; + b2 = move_pawns(pawnPushes & TRank3BB) & emptySquares; if (Type == MV_CHECK) { @@ -462,37 +458,37 @@ namespace { // don't generate captures. if (pawns & target) // For CHECK type target is dc bitboard { - dc1 = move_pawns(pawns & target & ~file_bb(ksq)) & emptySquares; - dc2 = move_pawns(dc1 & TRank3BB) & emptySquares; + dc1 = move_pawns(pawns & target & ~file_bb(ksq)) & emptySquares; + dc2 = move_pawns(dc1 & TRank3BB) & emptySquares; b1 |= dc1; b2 |= dc2; } } - SERIALIZE_MOVES_D(b1, -TDELTA_N); - SERIALIZE_MOVES_D(b2, -TDELTA_N -TDELTA_N); + SERIALIZE_MOVES_D(b1, -UP); + SERIALIZE_MOVES_D(b2, -UP -UP); } // En passant captures if ((Type == MV_CAPTURE || Type == MV_EVASION) && pos.ep_square() != SQ_NONE) { - assert(Us != WHITE || square_rank(pos.ep_square()) == RANK_6); - assert(Us != BLACK || square_rank(pos.ep_square()) == RANK_3); + assert(Us != WHITE || rank_of(pos.ep_square()) == RANK_6); + assert(Us != BLACK || rank_of(pos.ep_square()) == RANK_3); // 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 == MV_EVASION && !bit_is_set(target, pos.ep_square() - TDELTA_N)) + if (Type == MV_EVASION && !bit_is_set(target, pos.ep_square() - UP)) return mlist; b1 = pawns & pos.attacks_from(pos.ep_square(), Them); - assert(b1 != EmptyBoardBB); + assert(b1); while (b1) { to = pop_1st_bit(&b1); - (*mlist++).move = make_ep_move(to, pos.ep_square()); + (*mlist++).move = make_enpassant(to, pos.ep_square()); } } return mlist; @@ -501,38 +497,45 @@ namespace { template MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist, Color us) { - Color them = opposite_color(us); - Square ksq = pos.king_square(us); CastleRight f = CastleRight((Side == KING_SIDE ? WHITE_OO : WHITE_OOO) << us); - - assert(pos.piece_on(ksq) == make_piece(us, KING)); - - Square rsq = pos.castle_rook_square(f); - Square s1 = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1); - Square s2 = relative_square(us, Side == KING_SIDE ? SQ_F1 : SQ_D1); - Square s; - bool illegal = false; - - assert(pos.piece_on(rsq) == make_piece(us, ROOK)); - - // It is a bit complicated to correctly handle Chess960 - for (s = Min(ksq, s1); s <= Max(ksq, s1); s++) - if ( (s != ksq && s != rsq && !pos.square_is_empty(s)) + Color them = flip(us); + + // After castling, the rook and king's final positions are exactly the same + // in Chess960 as they would be in standard chess. + Square kfrom = pos.king_square(us); + Square rfrom = pos.castle_rook_square(f); + Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1); + Square rto = relative_square(us, Side == KING_SIDE ? SQ_F1 : SQ_D1); + + assert(!pos.in_check()); + assert(pos.piece_on(kfrom) == make_piece(us, KING)); + assert(pos.piece_on(rfrom) == make_piece(us, ROOK)); + + // Unimpeded rule: All the squares between the king's initial and final squares + // (including the final square), and all the squares between the rook's initial + // and final squares (including the final square), must be vacant except for + // the king and castling rook. + for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); s++) + if ( (s != kfrom && s != rfrom && !pos.square_is_empty(s)) ||(pos.attackers_to(s) & pos.pieces(them))) - illegal = true; + return mlist; - for (s = Min(rsq, s2); s <= Max(rsq, s2); s++) - if (s != ksq && s != rsq && !pos.square_is_empty(s)) - illegal = true; + for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); s++) + if (s != kfrom && s != rfrom && !pos.square_is_empty(s)) + return mlist; - if ( Side == QUEEN_SIDE - && square_file(rsq) == FILE_B - && ( pos.piece_on(relative_square(us, SQ_A1)) == make_piece(them, ROOK) - || pos.piece_on(relative_square(us, SQ_A1)) == make_piece(them, QUEEN))) - illegal = true; + // 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 (pos.is_chess960()) + { + Bitboard occ = pos.occupied_squares(); + clear_bit(&occ, rfrom); + if (pos.attackers_to(kto, occ) & pos.pieces(them)) + return mlist; + } - if (!illegal) - (*mlist++).move = make_castle_move(ksq, rsq); + (*mlist++).move = make_castle(kfrom, rfrom); return mlist; }