X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=97581e126316ecb79757388fe8ca66701a6b24ea;hp=f1c36156a3b08551393f829ddcf43aad872af91c;hb=d558f8a673b56b32ab6da8050f41b9e02fe1758b;hpb=f90274d8ce1aad4ad0595aacbceb74b6cbe306a8 diff --git a/src/position.cpp b/src/position.cpp index f1c36156..97581e12 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -251,8 +251,6 @@ 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; @@ -266,24 +264,12 @@ 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)))) - && ( file_of(square(sideToMove)) == file_of(st->epSquare) - || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove)))); + && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove)))); } - // 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 + if (!enpassant) st->epSquare = SQ_NONE; // 5-6. Halfmove clock and fullmove number @@ -295,10 +281,7 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th chess960 = isChess960; thisThread = th; - st->accumulator.state[WHITE] = Eval::NNUE::INIT; - st->accumulator.state[BLACK] = Eval::NNUE::INIT; - - assert(pos_is_ok()); + set_state(st); return *this; } @@ -517,11 +500,23 @@ bool Position::legal(Move m) const { assert(color_of(moved_piece(m)) == us); assert(piece_on(square(us)) == make_piece(us, KING)); - // st->previous->blockersForKing consider capsq as empty. - // If pinned, it has to move along the king ray. + // 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) == EN_PASSANT) - return !(st->previous->blockersForKing[sideToMove] & from) - || aligned(from, to, square(us)); + { + 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)); + } // Castling moves generation does not check if the castling path is clear of // enemy attacks, it is delayed at a later time: now! @@ -654,15 +649,18 @@ bool Position::gives_check(Move m) const { case PROMOTION: return attacks_bb(promotion_type(m), to, pieces() ^ from) & square(~sideToMove); - // 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. + // 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 EN_PASSANT: - return st->previous->checkersBB - || ( rank_of(square(~sideToMove)) == rank_of(from) - && st->previous->blockersForKing[~sideToMove] & from); + { + Square capsq = make_square(file_of(to), rank_of(from)); + Bitboard b = (pieces() ^ from ^ capsq) | to; + return (attacks_bb< ROOK>(square(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK)) + | (attacks_bb(square(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP)); + } default: //CASTLING { // Castling is encoded as 'king captures the rook' @@ -702,8 +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; @@ -1003,8 +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) { @@ -1080,8 +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;