X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=97581e126316ecb79757388fe8ca66701a6b24ea;hp=13010c1a43f49571193d745a144ad92a4867bb9d;hb=d558f8a673b56b32ab6da8050f41b9e02fe1758b;hpb=4513dafd026288c51ad1af2db9e4729798f877a8 diff --git a/src/position.cpp b/src/position.cpp index 13010c1a..97581e12 100644 --- a/src/position.cpp +++ b/src/position.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 @@ -34,6 +34,8 @@ using std::string; +namespace Stockfish { + namespace Zobrist { Key psq[PIECE_NB][SQUARE_NB]; @@ -71,13 +73,13 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) { << std::setfill(' ') << std::dec << "\nCheckers: "; for (Bitboard b = pos.checkers(); b; ) - os << UCI::square(pop_lsb(&b)) << " "; + os << UCI::square(pop_lsb(b)) << " "; if ( int(Tablebases::MaxCardinality) >= popcount(pos.pieces()) && !pos.can_castle(ANY_CASTLING)) { StateInfo st; - ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize); + ASSERT_ALIGNED(&st, Eval::NNUE::CacheLineSize); Position p; p.set(pos.fen(), pos.is_chess960(), &st, pos.this_thread()); @@ -280,8 +282,6 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th chess960 = isChess960; thisThread = th; set_state(st); - st->accumulator.state[WHITE] = Eval::NNUE::INIT; - st->accumulator.state[BLACK] = Eval::NNUE::INIT; return *this; } @@ -303,7 +303,7 @@ void Position::set_castling_right(Color c, Square rfrom) { Square kto = relative_square(c, cr & KING_SIDE ? SQ_G1 : SQ_C1); Square rto = relative_square(c, cr & KING_SIDE ? SQ_F1 : SQ_D1); - castlingPath[cr] = (between_bb(rfrom, rto) | between_bb(kfrom, kto) | rto | kto) + castlingPath[cr] = (between_bb(rfrom, rto) | between_bb(kfrom, kto)) & ~(kfrom | rfrom); } @@ -342,7 +342,7 @@ void Position::set_state(StateInfo* si) const { for (Bitboard b = pieces(); b; ) { - Square s = pop_lsb(&b); + Square s = pop_lsb(b); Piece pc = piece_on(s); si->key ^= Zobrist::psq[pc][s]; @@ -393,7 +393,7 @@ Position& Position::set(const string& code, Color c, StateInfo* si) { /// Position::fen() returns a FEN representation of the position. In case of /// Chess960 the Shredder-FEN notation is used. This is mainly a debugging function. -const string Position::fen() const { +string Position::fen() const { int emptyCnt; std::ostringstream ss; @@ -459,7 +459,7 @@ Bitboard Position::slider_blockers(Bitboard sliders, Square s, Bitboard& pinners while (snipers) { - Square sniperSq = pop_lsb(&snipers); + Square sniperSq = pop_lsb(snipers); Bitboard b = between_bb(s, sniperSq) & occupancy; if (b && !more_than_one(b)) @@ -503,7 +503,7 @@ bool Position::legal(Move m) const { // En passant captures are a tricky special case. Because they are rather // uncommon, we do it simply by testing whether the king is attacked after // the move is made. - if (type_of(m) == ENPASSANT) + if (type_of(m) == EN_PASSANT) { Square ksq = square(us); Square capsq = to - pawn_push(us); @@ -531,22 +531,20 @@ bool Position::legal(Move m) const { if (attackers_to(s) & pieces(~us)) return false; - // In case of Chess960, verify that when moving the castling rook we do - // not discover some hidden checker. + // In case of Chess960, verify if the Rook blocks some checks // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1. - return !chess960 - || !(attacks_bb(to, pieces() ^ to_sq(m)) & pieces(~us, ROOK, QUEEN)); + return !chess960 || !(blockers_for_king(us) & to_sq(m)); } // If the moving piece is a king, check whether the destination square is // attacked by the opponent. if (type_of(piece_on(from)) == KING) - return !(attackers_to(to) & pieces(~us)); + return !(attackers_to(to, pieces() ^ from) & pieces(~us)); // A non-king move is legal if and only if it is not pinned or it // is moving along the ray towards or away from the king. - return !(blockers_for_king(us) & from) - || aligned(from, to, square(us)); + return !(blockers_for_king(us) & from) + || aligned(from, to, square(us)); } @@ -562,8 +560,10 @@ bool Position::pseudo_legal(const Move m) const { Piece pc = moved_piece(m); // Use a slower but simpler function for uncommon cases + // yet we skip the legality check of MoveList(). if (type_of(m) != NORMAL) - return MoveList(*this).contains(m); + return checkers() ? MoveList< EVASIONS>(*this).contains(m) + : MoveList(*this).contains(m); // Is not a promotion, so promotion piece must be empty if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE) @@ -608,8 +608,8 @@ bool Position::pseudo_legal(const Move m) const { if (more_than_one(checkers())) return false; - // Our move must be a blocking evasion or a capture of the checking piece - if (!((between_bb(lsb(checkers()), square(us)) | checkers()) & to)) + // Our move must be a blocking interposition or a capture of the checking piece + if (!(between_bb(square(us), lsb(checkers())) & to)) return false; } // In case of king moves under check we have to remove king so as to catch @@ -653,7 +653,7 @@ bool Position::gives_check(Move m) const { // of direct checks and ordinary discovered check, so the only case we // need to handle is the unusual case of a discovered check through // the captured pawn. - case ENPASSANT: + case EN_PASSANT: { Square capsq = make_square(file_of(to), rank_of(from)); Bitboard b = (pieces() ^ from ^ capsq) | to; @@ -661,19 +661,15 @@ bool Position::gives_check(Move m) const { return (attacks_bb< ROOK>(square(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK)) | (attacks_bb(square(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP)); } - case CASTLING: + default: //CASTLING { - Square kfrom = from; - Square rfrom = to; // Castling is encoded as 'king captures the rook' - Square kto = relative_square(sideToMove, rfrom > kfrom ? SQ_G1 : SQ_C1); - Square rto = relative_square(sideToMove, rfrom > kfrom ? SQ_F1 : SQ_D1); + // Castling is encoded as 'king captures the rook' + Square ksq = square(~sideToMove); + Square rto = relative_square(sideToMove, to > from ? SQ_F1 : SQ_D1); - return (attacks_bb(rto) & square(~sideToMove)) - && (attacks_bb(rto, (pieces() ^ kfrom ^ rfrom) | rto | kto) & square(~sideToMove)); + return (attacks_bb(rto) & ksq) + && (attacks_bb(rto, pieces() ^ from ^ to) & ksq); } - default: - assert(false); - return false; } } @@ -704,8 +700,8 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { ++st->pliesFromNull; // Used by NNUE - st->accumulator.state[WHITE] = Eval::NNUE::EMPTY; - st->accumulator.state[BLACK] = Eval::NNUE::EMPTY; + st->accumulator.computed[WHITE] = false; + st->accumulator.computed[BLACK] = false; auto& dp = st->dirtyPiece; dp.dirty_num = 1; @@ -714,7 +710,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { Square from = from_sq(m); Square to = to_sq(m); Piece pc = piece_on(from); - Piece captured = type_of(m) == ENPASSANT ? make_piece(them, PAWN) : piece_on(to); + Piece captured = type_of(m) == EN_PASSANT ? make_piece(them, PAWN) : piece_on(to); assert(color_of(pc) == us); assert(captured == NO_PIECE || color_of(captured) == (type_of(m) != CASTLING ? them : us)); @@ -740,7 +736,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // update non-pawn material. if (type_of(captured) == PAWN) { - if (type_of(m) == ENPASSANT) + if (type_of(m) == EN_PASSANT) { capsq -= pawn_push(us); @@ -767,7 +763,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // Update board and piece lists remove_piece(capsq); - if (type_of(m) == ENPASSANT) + if (type_of(m) == EN_PASSANT) board[capsq] = NO_PIECE; // Update material hash key and prefetch access to materialTable @@ -813,7 +809,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // If the moving piece is a pawn do some special extra work if (type_of(pc) == PAWN) { - // Set en-passant square if the moved pawn can be captured + // Set en passant square if the moved pawn can be captured if ( (int(to) ^ int(from)) == 16 && (pawn_attacks_bb(us, to - pawn_push(us)) & pieces(them, PAWN))) { @@ -936,7 +932,7 @@ void Position::undo_move(Move m) { { Square capsq = to; - if (type_of(m) == ENPASSANT) + if (type_of(m) == EN_PASSANT) { capsq -= pawn_push(us); @@ -990,7 +986,7 @@ void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Squ } -/// Position::do(undo)_null_move() is used to do(undo) a "null move": it flips +/// Position::do_null_move() is used to do a "null move": it flips /// the side to move without executing any move on the board. void Position::do_null_move(StateInfo& newSt) { @@ -1005,8 +1001,8 @@ void Position::do_null_move(StateInfo& newSt) { st->dirtyPiece.dirty_num = 0; st->dirtyPiece.piece[0] = NO_PIECE; // Avoid checks in UpdateAccumulator() - st->accumulator.state[WHITE] = Eval::NNUE::EMPTY; - st->accumulator.state[BLACK] = Eval::NNUE::EMPTY; + st->accumulator.computed[WHITE] = false; + st->accumulator.computed[BLACK] = false; if (st->epSquare != SQ_NONE) { @@ -1015,7 +1011,7 @@ void Position::do_null_move(StateInfo& newSt) { } st->key ^= Zobrist::side; - prefetch(TT.first_entry(st->key)); + prefetch(TT.first_entry(key())); ++st->rule50; st->pliesFromNull = 0; @@ -1029,6 +1025,9 @@ void Position::do_null_move(StateInfo& newSt) { assert(pos_is_ok()); } + +/// Position::undo_null_move() must be used to undo a "null move" + void Position::undo_null_move() { assert(!checkers()); @@ -1040,7 +1039,7 @@ void Position::undo_null_move() { /// Position::key_after() computes the new hash key after the given move. Needed /// for speculative prefetch. It doesn't recognize special moves like castling, -/// en-passant and promotions. +/// en passant and promotions. Key Position::key_after(Move m) const { @@ -1065,7 +1064,7 @@ bool Position::see_ge(Move m, Value threshold) const { assert(is_ok(m)); - // Only deal with normal moves, assume others pass a simple see + // Only deal with normal moves, assume others pass a simple SEE if (type_of(m) != NORMAL) return VALUE_ZERO >= threshold; @@ -1079,8 +1078,9 @@ bool Position::see_ge(Move m, Value threshold) const { if (swap <= 0) return true; + assert(color_of(piece_on(from)) == sideToMove); Bitboard occupied = pieces() ^ from ^ to; - Color stm = color_of(piece_on(from)); + Color stm = sideToMove; Bitboard attackers = attackers_to(to, occupied); Bitboard stmAttackers, bb; int res = 1; @@ -1094,8 +1094,8 @@ bool Position::see_ge(Move m, Value threshold) const { if (!(stmAttackers = attackers & pieces(stm))) break; - // Don't allow pinned pieces to attack (except the king) as long as - // there are pinners on their original square. + // Don't allow pinned pieces to attack as long as there are + // pinners on their original square. if (pinners(~stm) & occupied) stmAttackers &= ~blockers_for_king(stm); @@ -1111,7 +1111,7 @@ bool Position::see_ge(Move m, Value threshold) const { if ((swap = PawnValueMg - swap) < res) break; - occupied ^= lsb(bb); + occupied ^= least_significant_square_bb(bb); attackers |= attacks_bb(to, occupied) & pieces(BISHOP, QUEEN); } @@ -1120,7 +1120,7 @@ bool Position::see_ge(Move m, Value threshold) const { if ((swap = KnightValueMg - swap) < res) break; - occupied ^= lsb(bb); + occupied ^= least_significant_square_bb(bb); } else if ((bb = stmAttackers & pieces(BISHOP))) @@ -1128,7 +1128,7 @@ bool Position::see_ge(Move m, Value threshold) const { if ((swap = BishopValueMg - swap) < res) break; - occupied ^= lsb(bb); + occupied ^= least_significant_square_bb(bb); attackers |= attacks_bb(to, occupied) & pieces(BISHOP, QUEEN); } @@ -1137,7 +1137,7 @@ bool Position::see_ge(Move m, Value threshold) const { if ((swap = RookValueMg - swap) < res) break; - occupied ^= lsb(bb); + occupied ^= least_significant_square_bb(bb); attackers |= attacks_bb(to, occupied) & pieces(ROOK, QUEEN); } @@ -1146,7 +1146,7 @@ bool Position::see_ge(Move m, Value threshold) const { if ((swap = QueenValueMg - swap) < res) break; - occupied ^= lsb(bb); + occupied ^= least_significant_square_bb(bb); attackers |= (attacks_bb(to, occupied) & pieces(BISHOP, QUEEN)) | (attacks_bb(to, occupied) & pieces(ROOK , QUEEN)); } @@ -1220,7 +1220,7 @@ bool Position::has_game_cycle(int ply) const { Square s1 = from_sq(move); Square s2 = to_sq(move); - if (!(between_bb(s1, s2) & pieces())) + if (!((between_bb(s1, s2) ^ s2) & pieces())) { if (ply > i) return true; @@ -1317,7 +1317,7 @@ bool Position::pos_is_ok() const { assert(0 && "pos_is_ok: Bitboards"); StateInfo si = *st; - ASSERT_ALIGNED(&si, Eval::NNUE::kCacheLineSize); + ASSERT_ALIGNED(&si, Eval::NNUE::CacheLineSize); set_state(&si); if (std::memcmp(&si, st, sizeof(StateInfo))) @@ -1342,3 +1342,5 @@ bool Position::pos_is_ok() const { return true; } + +} // namespace Stockfish