X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=de5d04c13ac8982368fcd10edf0eab96168058ec;hp=3f81994611975aaaf31c8f397b1613cf85edb297;hb=e9ab7353de074a0a970d334ac98b391e2222f77d;hpb=5fc8b27db9a1d9fffeb46d0e2ef40803c55fd4f9 diff --git a/src/position.cpp b/src/position.cpp index 3f819946..de5d04c1 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -172,11 +172,11 @@ Position& Position::operator=(const Position& pos) { } -/// Position::from_fen() initializes the position object with the given FEN -/// string. This function is not very robust - make sure that input FENs are -/// correct (this is assumed to be the responsibility of the GUI). +/// Position::set() initializes the position object with the given FEN string. +/// This function is not very robust - make sure that input FENs are correct, +/// this is assumed to be the responsibility of the GUI. -void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { +void Position::set(const string& fenStr, bool isChess960, Thread* th) { /* A FEN string defines a particular position using only the ASCII character set. @@ -214,13 +214,13 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { char col, row, token; size_t p; Square sq = SQ_A8; - std::istringstream fen(fenStr); + std::istringstream ss(fenStr); clear(); - fen >> std::noskipws; + ss >> std::noskipws; // 1. Piece placement - while ((fen >> token) && !isspace(token)) + while ((ss >> token) && !isspace(token)) { if (isdigit(token)) sq += Square(token - '0'); // Advance the given number of files @@ -236,16 +236,16 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { } // 2. Active color - fen >> token; + ss >> token; sideToMove = (token == 'w' ? WHITE : BLACK); - fen >> token; + ss >> token; // 3. Castling availability. Compatible with 3 standards: Normal FEN standard, // Shredder-FEN that uses the letters of the columns on which the rooks began // the game instead of KQkq and also X-FEN standard that, in case of Chess960, // if an inner rook is associated with the castling right, the castling tag is // replaced by the file letter of the involved rook, as for the Shredder-FEN. - while ((fen >> token) && !isspace(token)) + while ((ss >> token) && !isspace(token)) { Square rsq; Color c = islower(token) ? BLACK : WHITE; @@ -268,8 +268,8 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { } // 4. En passant square. Ignore if no pawn capture is possible - if ( ((fen >> col) && (col >= 'a' && col <= 'h')) - && ((fen >> row) && (row == '3' || row == '6'))) + if ( ((ss >> col) && (col >= 'a' && col <= 'h')) + && ((ss >> row) && (row == '3' || row == '6'))) { st->epSquare = File(col - 'a') | Rank(row - '1'); @@ -278,7 +278,7 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) { } // 5-6. Halfmove clock and fullmove number - fen >> std::skipws >> st->rule50 >> startPosPly; + ss >> std::skipws >> st->rule50 >> startPosPly; // Convert from fullmove starting from 1 to ply starting from 0, // handle also common incorrect FEN with fullmove = 0. @@ -325,12 +325,12 @@ void Position::set_castle_right(Color c, Square rfrom) { } -/// Position::to_fen() returns a FEN representation of the position. In case +/// Position::fen() returns a FEN representation of the position. In case /// of Chess960 the Shredder-FEN notation is used. Mainly a debugging function. -const string Position::to_fen() const { +const string Position::fen() const { - std::ostringstream fen; + std::ostringstream ss; Square sq; int emptyCnt; @@ -348,48 +348,48 @@ const string Position::to_fen() const { { if (emptyCnt > 0) { - fen << emptyCnt; + ss << emptyCnt; emptyCnt = 0; } - fen << PieceToChar[piece_on(sq)]; + ss << PieceToChar[piece_on(sq)]; } } if (emptyCnt > 0) - fen << emptyCnt; + ss << emptyCnt; if (rank > RANK_1) - fen << '/'; + ss << '/'; } - fen << (sideToMove == WHITE ? " w " : " b "); + ss << (sideToMove == WHITE ? " w " : " b "); if (can_castle(WHITE_OO)) - fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, KING_SIDE))))) : 'K'); + ss << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, KING_SIDE))))) : 'K'); if (can_castle(WHITE_OOO)) - fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, QUEEN_SIDE))))) : 'Q'); + ss << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, QUEEN_SIDE))))) : 'Q'); if (can_castle(BLACK_OO)) - fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, KING_SIDE))) : 'k'); + ss << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, KING_SIDE))) : 'k'); if (can_castle(BLACK_OOO)) - fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, QUEEN_SIDE))) : 'q'); + ss << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, QUEEN_SIDE))) : 'q'); if (st->castleRights == CASTLES_NONE) - fen << '-'; + ss << '-'; - fen << (ep_square() == SQ_NONE ? " - " : " " + square_to_string(ep_square()) + " ") + ss << (ep_square() == SQ_NONE ? " - " : " " + square_to_string(ep_square()) + " ") << st->rule50 << " " << 1 + (startPosPly - int(sideToMove == BLACK)) / 2; - return fen.str(); + return ss.str(); } -/// Position::print() prints an ASCII representation of the position to -/// the standard output. If a move is given then also the san is printed. +/// Position::pretty() returns an ASCII representation of the position to be +/// printed to the standard output together with the move's san notation. -void Position::print(Move move) const { +const string Position::pretty(Move move) const { const string dottedLine = "\n+---+---+---+---+---+---+---+---+"; const string twoRows = dottedLine + "\n| | . | | . | | . | | . |" @@ -397,17 +397,25 @@ void Position::print(Move move) const { string brd = twoRows + twoRows + twoRows + twoRows + dottedLine; - sync_cout; + std::ostringstream ss; if (move) - cout << "\nMove is: " << (sideToMove == BLACK ? ".." : "") - << move_to_san(*const_cast(this), move); + ss << "\nMove: " << (sideToMove == BLACK ? ".." : "") + << move_to_san(*const_cast(this), move); for (Square sq = SQ_A1; sq <= SQ_H8; sq++) if (piece_on(sq) != NO_PIECE) brd[513 - 68*rank_of(sq) + 4*file_of(sq)] = PieceToChar[piece_on(sq)]; - cout << brd << "\nFen is: " << to_fen() << "\nKey is: " << st->key << sync_endl; + ss << brd << "\nFen: " << fen() << "\nKey: " << st->key; + + if (checkers()) + { + ss << "\nCheckers: "; + for (Bitboard b = checkers(); b; ) + ss << square_to_string(pop_lsb(&b)) << " "; + } + return ss.str(); } @@ -473,37 +481,6 @@ Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { } -/// Position::move_attacks_square() tests whether a move from the current -/// position attacks a given square. - -bool Position::move_attacks_square(Move m, Square s) const { - - assert(is_ok(m)); - assert(is_ok(s)); - - Bitboard occ, xray; - Square from = from_sq(m); - Square to = to_sq(m); - Piece piece = piece_moved(m); - - assert(!is_empty(from)); - - // Update occupancy as if the piece is moving - occ = pieces() ^ from ^ to; - - // The piece moved in 'to' attacks the square 's' ? - if (attacks_from(piece, to, occ) & s) - return true; - - // Scan for possible X-ray attackers behind the moved piece - xray = (attacks_bb< ROOK>(s, occ) & pieces(color_of(piece), QUEEN, ROOK)) - | (attacks_bb(s, occ) & pieces(color_of(piece), QUEEN, BISHOP)); - - // Verify attackers are triggered by our move and not already existing - return xray && (xray ^ (xray & attacks_from(s))); -} - - /// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { @@ -551,20 +528,6 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { } -/// Position::move_is_legal() takes a random move and tests whether the move -/// is legal. This version is not very fast and should be used only in non -/// time-critical paths. - -bool Position::move_is_legal(const Move m) const { - - for (MoveList ml(*this); !ml.end(); ++ml) - if (ml.move() == m) - return true; - - return false; -} - - /// Position::is_pseudo_legal() takes a random move and tests whether the move /// is pseudo legal. It is used to validate moves from TT that can be corrupted /// due to SMP concurrent access or hash position key aliasing. @@ -572,14 +535,13 @@ bool Position::move_is_legal(const Move m) const { bool Position::is_pseudo_legal(const Move m) const { Color us = sideToMove; - Color them = ~sideToMove; Square from = from_sq(m); Square to = to_sq(m); Piece pc = piece_moved(m); // Use a slower but simpler function for uncommon cases if (type_of(m) != NORMAL) - return move_is_legal(m); + return MoveList(*this).contains(m); // Is not a promotion, so promotion piece must be empty if (promotion_type(m) - 2 != NO_PIECE_TYPE) @@ -591,7 +553,7 @@ bool Position::is_pseudo_legal(const Move m) const { return false; // The destination square cannot be occupied by a friendly piece - if (color_of(piece_on(to)) == us) + if (piece_on(to) != NO_PIECE && color_of(piece_on(to)) == us) return false; // Handle the special case of a pawn move @@ -617,7 +579,7 @@ bool Position::is_pseudo_legal(const Move m) const { case DELTA_SE: // Capture. The destination square must be occupied by an enemy // piece (en passant captures was handled earlier). - if (color_of(piece_on(to)) != them) + if (piece_on(to) == NO_PIECE || color_of(piece_on(to)) != ~us) return false; // From and to files must be one file apart, avoids a7h5 @@ -662,18 +624,16 @@ bool Position::is_pseudo_legal(const Move m) const { // Evasions generator already takes care to avoid some kind of illegal moves // and pl_move_is_legal() relies on this. So we have to take care that the // same kind of moves are filtered out here. - if (in_check()) + if (checkers()) { if (type_of(pc) != KING) { - Bitboard b = checkers(); - Square checksq = pop_lsb(&b); - - if (b) // double check ? In this case a king move is required + // Double check? In this case a king move is required + if (more_than_one(checkers())) return false; // Our move must be a blocking evasion or a capture of the checking piece - if (!((between_bb(checksq, king_square(us)) | checkers()) & to)) + if (!((between_bb(lsb(checkers()), king_square(us)) | checkers()) & to)) return false; } // In case of king moves under check we have to remove king so to catch @@ -718,15 +678,16 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { Color us = sideToMove; Square ksq = king_square(~us); - // Promotion with check ? - if (type_of(m) == PROMOTION) + switch (type_of(m)) + { + case PROMOTION: return attacks_from(Piece(promotion_type(m)), to, pieces() ^ from) & ksq; // En passant capture with check ? We have already handled the case // of direct checks and ordinary discovered check, the only case we // need to handle is the unusual case of a discovered check through // the captured pawn. - if (type_of(m) == ENPASSANT) + case ENPASSANT: { Square capsq = file_of(to) | rank_of(from); Bitboard b = (pieces() ^ from ^ capsq) | to; @@ -734,9 +695,7 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { return (attacks_bb< ROOK>(ksq, b) & pieces(us, QUEEN, ROOK)) | (attacks_bb(ksq, b) & pieces(us, QUEEN, BISHOP)); } - - // Castling with check ? - if (type_of(m) == CASTLE) + case CASTLE: { Square kfrom = from; Square rfrom = to; // 'King captures the rook' notation @@ -746,8 +705,10 @@ bool Position::move_gives_check(Move m, const CheckInfo& ci) const { return attacks_bb(rto, b) & ksq; } - - return false; + default: + assert(false); + return false; + } } @@ -770,9 +731,9 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI Key k = st->key; // Copy some fields of old state to our new StateInfo object except the ones - // which are recalculated from scratch anyway, then switch our state pointer - // to point to the new, ready to be updated, state. - memcpy(&newSt, st, sizeof(ReducedStateInfo)); + // which are going to be recalculated from scratch anyway, then switch our state + // pointer to point to the new, ready to be updated, state. + memcpy(&newSt, st, StateCopySize64 * sizeof(uint64_t)); newSt.previous = st; st = &newSt; @@ -801,7 +762,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI PieceType capture = type_of(m) == ENPASSANT ? PAWN : type_of(piece_on(to)); assert(color_of(piece) == us); - assert(color_of(piece_on(to)) != us); + assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == them); assert(capture != KING); if (capture) @@ -947,8 +908,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI } // Prefetch pawn and material hash tables - prefetch((char*)thisThread->pawnTable.entries[st->pawnKey]); - prefetch((char*)thisThread->materialTable.entries[st->materialKey]); + prefetch((char*)thisThread->pawnsTable[st->pawnKey]); + prefetch((char*)thisThread->materialTable[st->materialKey]); // Update incremental scores st->psqScore += psq_delta(piece, from, to); @@ -1190,7 +1151,7 @@ void Position::do_castle_move(Move m) { template void Position::do_null_move(StateInfo& backupSt) { - assert(!in_check()); + assert(!checkers()); // Back up the information necessary to undo the null move to the supplied // StateInfo object. Note that differently from normal case here backupSt @@ -1467,36 +1428,31 @@ Value Position::compute_non_pawn_material(Color c) const { /// Position::is_draw() tests whether the position is drawn by material, /// repetition, or the 50 moves rule. It does not detect stalemates, this /// must be done by the search. -template +template bool Position::is_draw() const { - // Draw by material? if ( !pieces(PAWN) && (non_pawn_material(WHITE) + non_pawn_material(BLACK) <= BishopValueMg)) return true; - // Draw by the 50 moves rule? - if (st->rule50 > 99 && (!in_check() || MoveList(*this).size())) + if (st->rule50 > 99 && (!checkers() || MoveList(*this).size())) return true; - // Draw by repetition? - if (!SkipRepetition) + if (CheckRepetition) { - int i = 4, e = std::min(st->rule50, st->pliesFromNull); + int i = 4, e = std::min(st->rule50, st->pliesFromNull), cnt; if (i <= e) { StateInfo* stp = st->previous->previous; - do { + for (cnt = 0; i <= e; i += 2) + { stp = stp->previous->previous; - if (stp->key == st->key) + if (stp->key == st->key && (!CheckThreeFold || ++cnt >= 2)) return true; - - i +=2; - - } while (i <= e); + } } } @@ -1504,8 +1460,9 @@ bool Position::is_draw() const { } // Explicit template instantiations -template bool Position::is_draw() const; -template bool Position::is_draw() const; +template bool Position::is_draw() const; +template bool Position::is_draw() const; +template bool Position::is_draw() const; /// Position::flip() flips position with the white and black sides reversed. This