X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=2eb30ca0d2a6d5536f3f4dc6d315bb9cd6d0de66;hp=396bff5f545c0f92bde33d12f23810e9d6d98745;hb=40cb0f076a62115af030c4524825d9ba73d61023;hpb=76a039027d14640852f60bda6d62ca16bdac3b9e diff --git a/src/position.cpp b/src/position.cpp index 396bff5f..2eb30ca0 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -1,8 +1,6 @@ /* 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) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + 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 @@ -79,6 +77,8 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) { && !pos.can_castle(ANY_CASTLING)) { StateInfo st; + ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize); + Position p; p.set(pos.fen(), pos.is_chess960(), &st, pos.this_thread()); Tablebases::ProbeState s1, s2; @@ -197,7 +197,6 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th std::memset(this, 0, sizeof(Position)); std::memset(si, 0, sizeof(StateInfo)); - std::fill_n(&pieceList[0][0], sizeof(pieceList) / sizeof(Square), SQ_NONE); st = si; ss >> std::noskipws; @@ -211,8 +210,7 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th else if (token == '/') sq += 2 * SOUTH; - else if ((idx = PieceToChar.find(token)) != string::npos) - { + else if ((idx = PieceToChar.find(token)) != string::npos) { put_piece(Piece(idx), sq); ++sq; } @@ -251,6 +249,8 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th set_castling_right(c, rsq); } + set_state(st); + // 4. En passant square. // Ignore if square is invalid or not on side to move relative rank 6. bool enpassant = false; @@ -264,12 +264,24 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th // a) side to move have a pawn threatening epSquare // b) there is an enemy pawn in front of epSquare // c) there is no piece on epSquare or behind epSquare + // d) enemy pawn didn't block a check of its own color by moving forward enpassant = pawn_attacks_bb(~sideToMove, st->epSquare) & pieces(sideToMove, PAWN) && (pieces(~sideToMove, PAWN) & (st->epSquare + pawn_push(~sideToMove))) - && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove)))); + && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove)))) + && ( file_of(square(sideToMove)) == file_of(st->epSquare) + || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove)))); } - if (!enpassant) + // It's necessary for st->previous to be intialized in this way because legality check relies on its existence + if (enpassant) { + st->previous = new StateInfo(); + remove_piece(st->epSquare - pawn_push(sideToMove)); + st->previous->checkersBB = attackers_to(square(~sideToMove)) & pieces(sideToMove); + st->previous->blockersForKing[WHITE] = slider_blockers(pieces(BLACK), square(WHITE), st->previous->pinners[BLACK]); + st->previous->blockersForKing[BLACK] = slider_blockers(pieces(WHITE), square(BLACK), st->previous->pinners[WHITE]); + put_piece(make_piece(~sideToMove, PAWN), st->epSquare - pawn_push(sideToMove)); + } + else st->epSquare = SQ_NONE; // 5-6. Halfmove clock and fullmove number @@ -281,7 +293,8 @@ 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; assert(pos_is_ok()); @@ -502,23 +515,11 @@ bool Position::legal(Move m) const { assert(color_of(moved_piece(m)) == us); assert(piece_on(square(us)) == make_piece(us, KING)); - // 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) - { - Square ksq = square(us); - Square capsq = to - pawn_push(us); - Bitboard occupied = (pieces() ^ from ^ capsq) | to; - - assert(to == ep_square()); - assert(moved_piece(m) == make_piece(us, PAWN)); - assert(piece_on(capsq) == make_piece(~us, PAWN)); - assert(piece_on(to) == NO_PIECE); - - return !(attacks_bb< ROOK>(ksq, occupied) & pieces(~us, QUEEN, ROOK)) - && !(attacks_bb(ksq, occupied) & pieces(~us, QUEEN, BISHOP)); - } + // st->previous->blockersForKing consider capsq as empty. + // If pinned, it has to move along the king ray. + if (type_of(m) == EN_PASSANT) + return !(st->previous->blockersForKing[sideToMove] & from) + || aligned(from, to, square(us)); // Castling moves generation does not check if the castling path is clear of // enemy attacks, it is delayed at a later time: now! @@ -533,11 +534,9 @@ 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 @@ -547,8 +546,8 @@ bool Position::legal(Move m) const { // 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)); } @@ -564,8 +563,10 @@ 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) @@ -651,31 +652,24 @@ bool Position::gives_check(Move m) const { case PROMOTION: return attacks_bb(promotion_type(m), to, pieces() ^ from) & square(~sideToMove); - // En passant capture with check? We have already handled the case - // 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: - { - Square capsq = make_square(file_of(to), rank_of(from)); - Bitboard b = (pieces() ^ from ^ capsq) | to; + // The double-pushed pawn blocked a check? En Passant will remove the blocker. + // The only discovery check that wasn't handle is through capsq and fromsq + // So the King must be in the same rank as fromsq to consider this possibility. + // st->previous->blockersForKing consider capsq as empty. + case EN_PASSANT: + return st->previous->checkersBB + || ( rank_of(square(~sideToMove)) == rank_of(from) + && st->previous->blockersForKing[~sideToMove] & from); - 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; } } @@ -705,12 +699,18 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { ++st->rule50; ++st->pliesFromNull; + // Used by NNUE + st->accumulator.state[WHITE] = Eval::NNUE::EMPTY; + st->accumulator.state[BLACK] = Eval::NNUE::EMPTY; + auto& dp = st->dirtyPiece; + dp.dirty_num = 1; + Color us = sideToMove; Color them = ~us; 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)); @@ -736,7 +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); @@ -752,10 +752,18 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { else st->nonPawnMaterial[them] -= PieceValue[MG][captured]; + if (Eval::useNNUE) + { + dp.dirty_num = 2; // 1 piece moved, 1 piece captured + dp.piece[1] = captured; + dp.from[1] = capsq; + dp.to[1] = SQ_NONE; + } + // 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 @@ -787,12 +795,21 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // Move the piece. The tricky Chess960 castling is handled earlier if (type_of(m) != CASTLING) + { + if (Eval::useNNUE) + { + dp.piece[0] = pc; + dp.from[0] = from; + dp.to[0] = to; + } + move_piece(from, to); + } // 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))) { @@ -810,6 +827,16 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { remove_piece(to); put_piece(promotion, to); + if (Eval::useNNUE) + { + // Promoting pawn to SQ_NONE, promoted piece from SQ_NONE + dp.to[0] = SQ_NONE; + dp.piece[dp.dirty_num] = promotion; + dp.from[dp.dirty_num] = SQ_NONE; + dp.to[dp.dirty_num] = to; + dp.dirty_num++; + } + // Update hash keys k ^= Zobrist::psq[pc][to] ^ Zobrist::psq[promotion][to]; st->pawnKey ^= Zobrist::psq[pc][to]; @@ -905,7 +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); @@ -938,6 +965,18 @@ void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Squ rto = relative_square(us, kingSide ? SQ_F1 : SQ_D1); to = relative_square(us, kingSide ? SQ_G1 : SQ_C1); + if (Do && Eval::useNNUE) + { + auto& dp = st->dirtyPiece; + dp.piece[0] = make_piece(us, KING); + dp.from[0] = from; + dp.to[0] = to; + dp.piece[1] = make_piece(us, ROOK); + dp.from[1] = rfrom; + dp.to[1] = rto; + dp.dirty_num = 2; + } + // Remove both pieces first since squares could overlap in Chess960 remove_piece(Do ? from : to); remove_piece(Do ? rfrom : rto); @@ -955,10 +994,16 @@ void Position::do_null_move(StateInfo& newSt) { assert(!checkers()); assert(&newSt != st); - std::memcpy(&newSt, st, sizeof(StateInfo)); + std::memcpy(&newSt, st, offsetof(StateInfo, accumulator)); + newSt.previous = st; st = &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; + if (st->epSquare != SQ_NONE) { st->key ^= Zobrist::enpassant[file_of(st->epSquare)]; @@ -966,7 +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; @@ -991,7 +1036,7 @@ 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 { @@ -1016,7 +1061,7 @@ 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; @@ -1047,8 +1092,8 @@ bool Position::see_ge(Move m, Value threshold) const { // Don't allow pinned pieces to attack (except the king) as long as // there are pinners on their original square. - if (st->pinners[~stm] & occupied) - stmAttackers &= ~st->blockersForKing[stm]; + if (pinners(~stm) & occupied) + stmAttackers &= ~blockers_for_king(stm); if (!stmAttackers) break; @@ -1268,21 +1313,17 @@ bool Position::pos_is_ok() const { assert(0 && "pos_is_ok: Bitboards"); StateInfo si = *st; + ASSERT_ALIGNED(&si, Eval::NNUE::kCacheLineSize); + set_state(&si); if (std::memcmp(&si, st, sizeof(StateInfo))) assert(0 && "pos_is_ok: State"); for (Piece pc : Pieces) - { if ( pieceCount[pc] != popcount(pieces(color_of(pc), type_of(pc))) || pieceCount[pc] != std::count(board, board + SQUARE_NB, pc)) assert(0 && "pos_is_ok: Pieces"); - for (int i = 0; i < pieceCount[pc]; ++i) - if (board[pieceList[pc][i]] != pc || index[pieceList[pc][i]] != i) - assert(0 && "pos_is_ok: Index"); - } - for (Color c : { WHITE, BLACK }) for (CastlingRights cr : {c & KING_SIDE, c & QUEEN_SIDE}) {