X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=0336a832a363291d4c07d5ade63899db790a9bca;hp=7ee63b22aa6cdf16076e75214302ac6e77acb9d5;hb=e6f2d43b8a02aeb0180466d75be425800ec7c24d;hpb=1588a4e84695e48e47c5c8b83d14ead285530c45 diff --git a/src/position.cpp b/src/position.cpp index 7ee63b22..0336a832 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -76,15 +76,52 @@ CheckInfo::CheckInfo(const Position& pos) { checkSq[KING] = EmptyBoardBB; } + +/// Position c'tors. Here we always create a slower but safer copy of +/// the original position or the FEN string, we want the new born Position +/// object do not depend on any external data. Instead if we know what we +/// are doing and we need speed we can create a position with default +/// c'tor Position() and then use just fast_copy(). + +Position::Position() {} + Position::Position(const Position& pos) { - copy(pos); + + fast_copy(pos); + detach(); // Always detach() in copy c'tor to avoid surprises } Position::Position(const string& fen) { + from_fen(fen); } +/// Position::fast_copy() creates a partial copy of the given position, +/// only data that changes with a do_move() / undo_move() cycle is copied, +/// in particular for stateInfo are copied only the pointers, so that the +/// actual data remains stored in the parent Position. This is not a problem +/// if the parent Position is known not to be destroyed while we are still alive, +/// as is the common case, see detach() otherwise. + +void Position::fast_copy(const Position& pos) { + + memcpy(this, &pos, sizeof(Position)); +} + + +/// Position::detach() copies the content of the current state and castling +/// masks inside the position itself. This is needed when the st pointee could +/// become stale, as example because the caller is about to going out of scope. + +void Position::detach() { + + startState = *st; + st = &startState; + st->previous = NULL; // as a safe guard +} + + /// 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). @@ -143,61 +180,61 @@ void Position::from_fen(const string& fen) { } i++; - while(strchr("KQkqabcdefghABCDEFGH-", fen[i])) { - if (fen[i] == '-') - { - i++; - break; - } - else if(fen[i] == 'K') allow_oo(WHITE); - else if(fen[i] == 'Q') allow_ooo(WHITE); - else if(fen[i] == 'k') allow_oo(BLACK); - else if(fen[i] == 'q') allow_ooo(BLACK); - else if(fen[i] >= 'A' && fen[i] <= 'H') { - File rookFile, kingFile = FILE_NONE; - for(Square square = SQ_B1; square <= SQ_G1; square++) - if(piece_on(square) == WK) - kingFile = square_file(square); - if(kingFile == FILE_NONE) { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - initialKFile = kingFile; - rookFile = File(fen[i] - 'A') + FILE_A; - if(rookFile < initialKFile) { - allow_ooo(WHITE); - initialQRFile = rookFile; - } - else { - allow_oo(WHITE); - initialKRFile = rookFile; + while (strchr("KQkqabcdefghABCDEFGH-", fen[i])) { + if (fen[i] == '-') + { + i++; + break; } - } - else if(fen[i] >= 'a' && fen[i] <= 'h') { - File rookFile, kingFile = FILE_NONE; - for(Square square = SQ_B8; square <= SQ_G8; square++) - if(piece_on(square) == BK) - kingFile = square_file(square); - if(kingFile == FILE_NONE) { - std::cout << "Error in FEN at character " << i << std::endl; - return; + else if (fen[i] == 'K') allow_oo(WHITE); + else if (fen[i] == 'Q') allow_ooo(WHITE); + else if (fen[i] == 'k') allow_oo(BLACK); + else if (fen[i] == 'q') allow_ooo(BLACK); + else if (fen[i] >= 'A' && fen[i] <= 'H') { + File rookFile, kingFile = FILE_NONE; + for (Square square = SQ_B1; square <= SQ_G1; square++) + if (piece_on(square) == WK) + kingFile = square_file(square); + if (kingFile == FILE_NONE) { + std::cout << "Error in FEN at character " << i << std::endl; + return; + } + initialKFile = kingFile; + rookFile = File(fen[i] - 'A') + FILE_A; + if (rookFile < initialKFile) { + allow_ooo(WHITE); + initialQRFile = rookFile; + } + else { + allow_oo(WHITE); + initialKRFile = rookFile; + } } - initialKFile = kingFile; - rookFile = File(fen[i] - 'a') + FILE_A; - if(rookFile < initialKFile) { - allow_ooo(BLACK); - initialQRFile = rookFile; + else if (fen[i] >= 'a' && fen[i] <= 'h') { + File rookFile, kingFile = FILE_NONE; + for (Square square = SQ_B8; square <= SQ_G8; square++) + if (piece_on(square) == BK) + kingFile = square_file(square); + if (kingFile == FILE_NONE) { + std::cout << "Error in FEN at character " << i << std::endl; + return; + } + initialKFile = kingFile; + rookFile = File(fen[i] - 'a') + FILE_A; + if (rookFile < initialKFile) { + allow_ooo(BLACK); + initialQRFile = rookFile; + } + else { + allow_oo(BLACK); + initialKRFile = rookFile; + } } else { - allow_oo(BLACK); - initialKRFile = rookFile; + std::cout << "Error in FEN at character " << i << std::endl; + return; } - } - else { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - i++; + i++; } // Skip blanks @@ -277,16 +314,16 @@ const string Position::to_fen() const { if (can_castle_queenside(WHITE)) fen += 'Q'; if (can_castle_kingside(BLACK)) fen += 'k'; if (can_castle_queenside(BLACK)) fen += 'q'; - } + } else { - if (can_castle_kingside(WHITE)) - fen += toupper(file_to_char(initialKRFile)); - if (can_castle_queenside(WHITE)) - fen += toupper(file_to_char(initialQRFile)); - if (can_castle_kingside(BLACK)) + if (can_castle_kingside(WHITE)) + fen += char(toupper(file_to_char(initialKRFile))); + if (can_castle_queenside(WHITE)) + fen += char(toupper(file_to_char(initialQRFile))); + if (can_castle_kingside(BLACK)) fen += file_to_char(initialKRFile); - if (can_castle_queenside(BLACK)) + if (can_castle_queenside(BLACK)) fen += file_to_char(initialQRFile); } } else @@ -319,8 +356,9 @@ void Position::print(Move m) const { std::cout << std::endl; if (m != MOVE_NONE) { + Position p(*this); string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : ""); - std::cout << "Move is: " << col << move_to_san(*this, m) << std::endl; + std::cout << "Move is: " << col << move_to_san(p, m) << std::endl; } for (Rank rank = RANK_8; rank >= RANK_1; rank--) { @@ -345,15 +383,6 @@ void Position::print(Move m) const { } -/// Position::copy() creates a copy of the input position. - -void Position::copy(const Position& pos) { - - memcpy(this, &pos, sizeof(Position)); - saveState(); // detach and copy state info -} - - /// Position:hidden_checkers<>() returns a bitboard of all pinned (against the /// king) pieces for the given color and for the given pinner type. Or, when /// template parameter FindPinned is false, the pieces of the given color @@ -1272,6 +1301,11 @@ void Position::undo_null_move() { } +/// +PieceType Position::captured_piece() const { + return st->capture; +} + /// Position::see() is a static exchange evaluator: It tries to estimate the /// material gain or loss resulting from a move. There are three versions of /// this function: One which takes a destination square as input, one takes a @@ -1443,19 +1477,6 @@ int Position::see(Square from, Square to) const { } -/// Position::saveState() copies the content of the current state -/// inside startState and makes st point to it. This is needed -/// when the st pointee could become stale, as example because -/// the caller is about to going out of scope. - -void Position::saveState() { - - startState = *st; - st = &startState; - st->previous = NULL; // as a safe guard -} - - /// Position::clear() erases the position object to a pristine state, with an /// empty board, white to move, and no castling rights. @@ -1574,7 +1595,7 @@ Key Position::compute_pawn_key() const { for (Color c = WHITE; c <= BLACK; c++) { b = pieces(PAWN, c); - while(b) + while (b) { s = pop_1st_bit(&b); result ^= zobrist[c][PAWN][s]; @@ -1618,7 +1639,7 @@ Score Position::compute_value() const { for (PieceType pt = PAWN; pt <= KING; pt++) { b = pieces(pt, c); - while(b) + while (b) { s = pop_1st_bit(&b); assert(piece_on(s) == piece_of_color_and_type(c, pt)); @@ -1657,6 +1678,7 @@ 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. +// FIXME: Currently we are not handling 50 move rule correctly when in check bool Position::is_draw() const { @@ -1670,7 +1692,7 @@ bool Position::is_draw() const { return true; // Draw by repetition? - for (int i = 2; i < Min(Min(gamePly, st->rule50), st->pliesFromNull); i += 2) + for (int i = 4; i <= Min(Min(gamePly, st->rule50), st->pliesFromNull); i += 2) if (history[gamePly - i] == st->key) return true; @@ -1990,9 +2012,9 @@ bool Position::is_ok(int* failedStep) const { if (failedStep) (*failedStep)++; if (debugPieceList) { - for(Color c = WHITE; c <= BLACK; c++) - for(PieceType pt = PAWN; pt <= KING; pt++) - for(int i = 0; i < pieceCount[c][pt]; i++) + for (Color c = WHITE; c <= BLACK; c++) + for (PieceType pt = PAWN; pt <= KING; pt++) + for (int i = 0; i < pieceCount[c][pt]; i++) { if (piece_on(piece_list(c, pt, i)) != piece_of_color_and_type(c, pt)) return false; @@ -2004,20 +2026,20 @@ bool Position::is_ok(int* failedStep) const { if (failedStep) (*failedStep)++; if (debugCastleSquares) { - for (Color c = WHITE; c <= BLACK; c++) { - if (can_castle_kingside(c) && piece_on(initial_kr_square(c)) != piece_of_color_and_type(c, ROOK)) - return false; - if (can_castle_queenside(c) && piece_on(initial_qr_square(c)) != piece_of_color_and_type(c, ROOK)) - return false; - } - if (castleRightsMask[initial_kr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OO)) - return false; - if (castleRightsMask[initial_qr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OOO)) - return false; - if (castleRightsMask[initial_kr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OO)) - return false; - if (castleRightsMask[initial_qr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OOO)) - return false; + for (Color c = WHITE; c <= BLACK; c++) { + if (can_castle_kingside(c) && piece_on(initial_kr_square(c)) != piece_of_color_and_type(c, ROOK)) + return false; + if (can_castle_queenside(c) && piece_on(initial_qr_square(c)) != piece_of_color_and_type(c, ROOK)) + return false; + } + if (castleRightsMask[initial_kr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OO)) + return false; + if (castleRightsMask[initial_qr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OOO)) + return false; + if (castleRightsMask[initial_kr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OO)) + return false; + if (castleRightsMask[initial_qr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OOO)) + return false; } if (failedStep) *failedStep = 0;