X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fposition.cpp;h=eda26014c32c49330a57cbdd996102a555011b0d;hb=856a5f3aaaf8b9d53599963decacd4476b55c034;hp=9db41b784918388f31b9f4d5a3385c043d2ae4f8;hpb=6fa6da3ee13d2b7bdbec3cd24ff8ca43233c74fb;p=stockfish diff --git a/src/position.cpp b/src/position.cpp index 9db41b78..eda26014 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -19,7 +19,7 @@ #include #include -#include // For std::memset, std::memcmp +#include // For std::memset #include #include @@ -182,7 +182,7 @@ void Position::init() { Position& Position::operator=(const Position& pos) { std::memcpy(this, &pos, sizeof(Position)); - std::memcpy(&startState, st, sizeof(StateInfo)); + startState = *st; st = &startState; nodes = 0; @@ -265,7 +265,7 @@ void Position::set(const string& fenStr, bool isChess960, Thread* th) { else if ((idx = PieceToChar.find(token)) != string::npos) { - put_piece(color_of(Piece(idx)), type_of(Piece(idx)), sq); + put_piece(sq, color_of(Piece(idx)), type_of(Piece(idx))); ++sq; } } @@ -375,13 +375,13 @@ void Position::set_state(StateInfo* si) const { si->psq += psq[color_of(pc)][type_of(pc)][s]; } - if (si->epSquare != SQ_NONE) - si->key ^= Zobrist::enpassant[file_of(si->epSquare)]; + if (ep_square() != SQ_NONE) + si->key ^= Zobrist::enpassant[file_of(ep_square())]; if (sideToMove == BLACK) si->key ^= Zobrist::side; - si->key ^= Zobrist::castling[si->castlingRights]; + si->key ^= Zobrist::castling[st->castlingRights]; for (Bitboard b = pieces(PAWN); b; ) { @@ -498,7 +498,7 @@ Bitboard Position::attackers_to(Square s, Bitboard occupied) const { return (attacks_from(s, BLACK) & pieces(WHITE, PAWN)) | (attacks_from(s, WHITE) & pieces(BLACK, PAWN)) | (attacks_from(s) & pieces(KNIGHT)) - | (attacks_bb(s, occupied) & pieces(ROOK, QUEEN)) + | (attacks_bb(s, occupied) & pieces(ROOK, QUEEN)) | (attacks_bb(s, occupied) & pieces(BISHOP, QUEEN)) | (attacks_from(s) & pieces(KING)); } @@ -566,7 +566,7 @@ bool Position::pseudo_legal(const Move m) const { return MoveList(*this).contains(m); // Is not a promotion, so promotion piece must be empty - if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE) + if (promotion_type(m) - 2 != NO_PIECE_TYPE) return false; // If the 'from' square is not occupied by a piece belonging to the side to @@ -587,7 +587,9 @@ bool Position::pseudo_legal(const Move m) const { return false; if ( !(attacks_from(from, us) & pieces(~us) & to) // Not a capture + && !((from + pawn_push(us) == to) && empty(to)) // Not a single push + && !( (from + 2 * pawn_push(us) == to) // Not a double push && (rank_of(from) == relative_rank(us, RANK_2)) && empty(to) @@ -632,9 +634,10 @@ bool Position::gives_check(Move m, const CheckInfo& ci) const { Square from = from_sq(m); Square to = to_sq(m); + PieceType pt = type_of(piece_on(from)); // Is there a direct check? - if (ci.checkSq[type_of(piece_on(from))] & to) + if (ci.checkSq[pt] & to) return true; // Is there a discovered check? @@ -684,21 +687,31 @@ bool Position::gives_check(Move m, const CheckInfo& ci) const { /// to a StateInfo object. The move is assumed to be legal. Pseudo-legal /// moves should be filtered out before this function is called. -void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { +void Position::do_move(Move m, StateInfo& newSt) { + + CheckInfo ci(*this); + do_move(m, newSt, gives_check(m, ci)); +} + +void Position::do_move(Move m, StateInfo& newSt, bool moveIsCheck) { assert(is_ok(m)); assert(&newSt != st); ++nodes; - Key k = st->key ^ Zobrist::side; + Key k = st->key; // Copy some fields of the old state to our new StateInfo object except the // ones which are going to be recalculated from scratch anyway and then switch // our state pointer to point to the new (ready to be updated) state. - std::memcpy(&newSt, st, offsetof(StateInfo, key)); + std::memcpy(&newSt, st, StateCopySize64 * sizeof(uint64_t)); + newSt.previous = st; st = &newSt; + // Update side to move + k ^= Zobrist::side; + // Increment ply counters. In particular, rule50 will be reset to zero later on // in case of a capture or a pawn move. ++gamePly; @@ -709,19 +722,20 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { Color them = ~us; Square from = from_sq(m); Square to = to_sq(m); - PieceType pt = type_of(piece_on(from)); + Piece pc = piece_on(from); + PieceType pt = type_of(pc); PieceType captured = type_of(m) == ENPASSANT ? PAWN : type_of(piece_on(to)); - assert(color_of(piece_on(from)) == us); - assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == (type_of(m) != CASTLING ? them : us)); + assert(color_of(pc) == us); + assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == them || type_of(m) == CASTLING); assert(captured != KING); if (type_of(m) == CASTLING) { - assert(pt == KING); + assert(pc == make_piece(us, KING)); Square rfrom, rto; - do_castling(us, from, to, rfrom, rto); + do_castling(from, to, rfrom, rto); captured = NO_PIECE_TYPE; st->psq += psq[us][ROOK][rto] - psq[us][ROOK][rfrom]; @@ -738,7 +752,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { { if (type_of(m) == ENPASSANT) { - capsq -= pawn_push(us); + capsq += pawn_push(them); assert(pt == PAWN); assert(to == st->epSquare); @@ -746,7 +760,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { assert(piece_on(to) == NO_PIECE); assert(piece_on(capsq) == make_piece(them, PAWN)); - board[capsq] = NO_PIECE; // Not done by remove_piece() + board[capsq] = NO_PIECE; } st->pawnKey ^= Zobrist::psq[them][PAWN][capsq]; @@ -755,12 +769,12 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { st->nonPawnMaterial[them] -= PieceValue[MG][captured]; // Update board and piece lists - remove_piece(them, captured, capsq); + remove_piece(capsq, them, captured); // Update material hash key and prefetch access to materialTable k ^= Zobrist::psq[them][captured][capsq]; st->materialKey ^= Zobrist::psq[them][captured][pieceCount[them][captured]]; - prefetch(thisThread->materialTable[st->materialKey]); + prefetch((char*)thisThread->materialTable[st->materialKey]); // Update incremental scores st->psq -= psq[them][captured][capsq]; @@ -789,16 +803,16 @@ 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) - move_piece(us, pt, from, to); + move_piece(from, to, us, pt); // If the moving piece is a pawn do some special extra work if (pt == PAWN) { // Set en-passant square if the moved pawn can be captured if ( (int(to) ^ int(from)) == 16 - && (attacks_from(to - pawn_push(us), us) & pieces(them, PAWN))) + && (attacks_from(from + pawn_push(us), us) & pieces(them, PAWN))) { - st->epSquare = (from + to) / 2; + st->epSquare = Square((from + to) / 2); k ^= Zobrist::enpassant[file_of(st->epSquare)]; } @@ -809,8 +823,8 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { assert(relative_rank(us, to) == RANK_8); assert(promotion >= KNIGHT && promotion <= QUEEN); - remove_piece(us, PAWN, to); - put_piece(us, promotion, to); + remove_piece(to, us, PAWN); + put_piece(to, us, promotion); // Update hash keys k ^= Zobrist::psq[us][PAWN][to] ^ Zobrist::psq[us][promotion][to]; @@ -827,7 +841,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // Update pawn hash key and prefetch access to pawnsTable st->pawnKey ^= Zobrist::psq[us][PAWN][from] ^ Zobrist::psq[us][PAWN][to]; - prefetch(thisThread->pawnsTable[st->pawnKey]); + prefetch((char*)thisThread->pawnsTable[st->pawnKey]); // Reset rule 50 draw counter st->rule50 = 0; @@ -842,8 +856,8 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) { // Update the key with the final value st->key = k; - // Calculate checkers bitboard (if move gives check) - st->checkersBB = givesCheck ? attackers_to(king_square(them)) & pieces(us) : 0; + // Calculate checkers bitboard (if move is check) + st->checkersBB = moveIsCheck ? attackers_to(king_square(them)) & pieces(us) : 0; sideToMove = ~sideToMove; @@ -870,23 +884,23 @@ void Position::undo_move(Move m) { if (type_of(m) == PROMOTION) { - assert(relative_rank(us, to) == RANK_8); assert(pt == promotion_type(m)); - assert(pt >= KNIGHT && pt <= QUEEN); + assert(relative_rank(us, to) == RANK_8); + assert(promotion_type(m) >= KNIGHT && promotion_type(m) <= QUEEN); - remove_piece(us, pt, to); - put_piece(us, PAWN, to); + remove_piece(to, us, promotion_type(m)); + put_piece(to, us, PAWN); pt = PAWN; } if (type_of(m) == CASTLING) { Square rfrom, rto; - do_castling(us, from, to, rfrom, rto); + do_castling(from, to, rfrom, rto); } else { - move_piece(us, pt, to, from); // Put the piece back at the source square + move_piece(to, from, us, pt); // Put the piece back at the source square if (st->capturedType) { @@ -900,10 +914,9 @@ void Position::undo_move(Move m) { assert(to == st->previous->epSquare); assert(relative_rank(us, to) == RANK_6); assert(piece_on(capsq) == NO_PIECE); - assert(st->capturedType == PAWN); } - put_piece(~us, st->capturedType, capsq); // Restore the captured piece + put_piece(capsq, ~us, st->capturedType); // Restore the captured piece } } @@ -918,19 +931,19 @@ void Position::undo_move(Move m) { /// Position::do_castling() is a helper used to do/undo a castling move. This /// is a bit tricky, especially in Chess960. template -void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto) { +void Position::do_castling(Square from, Square& to, Square& rfrom, Square& rto) { bool kingSide = to > from; rfrom = to; // Castling is encoded as "king captures friendly rook" - rto = relative_square(us, kingSide ? SQ_F1 : SQ_D1); - to = relative_square(us, kingSide ? SQ_G1 : SQ_C1); + rto = relative_square(sideToMove, kingSide ? SQ_F1 : SQ_D1); + to = relative_square(sideToMove, kingSide ? SQ_G1 : SQ_C1); // Remove both pieces first since squares could overlap in Chess960 - remove_piece(us, KING, Do ? from : to); - remove_piece(us, ROOK, Do ? rfrom : rto); + remove_piece(Do ? from : to, sideToMove, KING); + remove_piece(Do ? rfrom : rto, sideToMove, ROOK); board[Do ? from : to] = board[Do ? rfrom : rto] = NO_PIECE; // Since remove_piece doesn't do it for us - put_piece(us, KING, Do ? to : from); - put_piece(us, ROOK, Do ? rto : rfrom); + put_piece(Do ? to : from, sideToMove, KING); + put_piece(Do ? rto : rfrom, sideToMove, ROOK); } @@ -940,9 +953,9 @@ void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Squ void Position::do_null_move(StateInfo& newSt) { assert(!checkers()); - assert(&newSt != st); - std::memcpy(&newSt, st, sizeof(StateInfo)); + std::memcpy(&newSt, st, sizeof(StateInfo)); // Fully copy here + newSt.previous = st; st = &newSt; @@ -953,7 +966,7 @@ void Position::do_null_move(StateInfo& newSt) { } st->key ^= Zobrist::side; - prefetch(TT.first_entry(st->key)); + prefetch((char*)TT.first_entry(st->key)); ++st->rule50; st->pliesFromNull = 0; @@ -1063,11 +1076,21 @@ Value Position::see(Move m) const { // Locate and remove the next least valuable attacker captured = min_attacker(byTypeBB, to, stmAttackers, occupied, attackers); + + // Stop before processing a king capture + if (captured == KING) + { + if (stmAttackers == attackers) + ++slIndex; + + break; + } + stm = ~stm; stmAttackers = attackers & pieces(stm); ++slIndex; - } while (stmAttackers && (captured != KING || (--slIndex, false))); // Stop before a king capture + } while (stmAttackers); // Having built the swap list, we negamax through it to find the best // achievable score from the point of view of the side to move. @@ -1102,6 +1125,10 @@ bool Position::is_draw() const { /// Position::flip() flips position with the white and black sides reversed. This /// is only useful for debugging e.g. for finding evaluation symmetry bugs. +static char toggle_case(char c) { + return char(islower(c) ? toupper(c) : tolower(c)); +} + void Position::flip() { string f, token; @@ -1119,8 +1146,7 @@ void Position::flip() { ss >> token; // Castling availability f += token + " "; - std::transform(f.begin(), f.end(), f.begin(), - [](char c) { return char(islower(c) ? toupper(c) : tolower(c)); }); + std::transform(f.begin(), f.end(), f.begin(), toggle_case); ss >> token; // En passant square f += (token == "-" ? token : token.replace(1, 1, token[1] == '3' ? "6" : "3")); @@ -1137,77 +1163,96 @@ void Position::flip() { /// Position::pos_is_ok() performs some consistency checks for the position object. /// This is meant to be helpful when debugging. -bool Position::pos_is_ok(int* failedStep) const { +bool Position::pos_is_ok(int* step) const { + + // Which parts of the position should be verified? + const bool all = false; + + const bool testBitboards = all || false; + const bool testState = all || false; + const bool testKingCount = all || false; + const bool testKingCapture = all || false; + const bool testPieceCounts = all || false; + const bool testPieceList = all || false; + const bool testCastlingSquares = all || false; - const bool Fast = true; // Quick (default) or full check? + if (step) + *step = 1; - enum { Default, King, Bitboards, State, Lists, Castling }; + if ( (sideToMove != WHITE && sideToMove != BLACK) + || piece_on(king_square(WHITE)) != W_KING + || piece_on(king_square(BLACK)) != B_KING + || ( ep_square() != SQ_NONE + && relative_rank(sideToMove, ep_square()) != RANK_6)) + return false; - for (int step = Default; step <= (Fast ? Default : Castling); step++) + if (step && ++*step, testBitboards) { - if (failedStep) - *failedStep = step; - - if (step == Default) - if ( (sideToMove != WHITE && sideToMove != BLACK) - || piece_on(king_square(WHITE)) != W_KING - || piece_on(king_square(BLACK)) != B_KING - || ( ep_square() != SQ_NONE - && relative_rank(sideToMove, ep_square()) != RANK_6)) - return false; + // The intersection of the white and black pieces must be empty + if (pieces(WHITE) & pieces(BLACK)) + return false; - if (step == King) - if ( std::count(board, board + SQUARE_NB, W_KING) != 1 - || std::count(board, board + SQUARE_NB, B_KING) != 1 - || attackers_to(king_square(~sideToMove)) & pieces(sideToMove)) - return false; + // The union of the white and black pieces must be equal to all + // occupied squares + if ((pieces(WHITE) | pieces(BLACK)) != pieces()) + return false; - if (step == Bitboards) - { - if ( (pieces(WHITE) & pieces(BLACK)) - ||(pieces(WHITE) | pieces(BLACK)) != pieces()) - return false; + // Separate piece type bitboards must have empty intersections + for (PieceType p1 = PAWN; p1 <= KING; ++p1) + for (PieceType p2 = PAWN; p2 <= KING; ++p2) + if (p1 != p2 && (pieces(p1) & pieces(p2))) + return false; + } - for (PieceType p1 = PAWN; p1 <= KING; ++p1) - for (PieceType p2 = PAWN; p2 <= KING; ++p2) - if (p1 != p2 && (pieces(p1) & pieces(p2))) - return false; - } + if (step && ++*step, testState) + { + StateInfo si; + set_state(&si); + if ( st->key != si.key + || st->pawnKey != si.pawnKey + || st->materialKey != si.materialKey + || st->nonPawnMaterial[WHITE] != si.nonPawnMaterial[WHITE] + || st->nonPawnMaterial[BLACK] != si.nonPawnMaterial[BLACK] + || st->psq != si.psq + || st->checkersBB != si.checkersBB) + return false; + } - if (step == State) - { - StateInfo si = *st; - set_state(&si); - if (std::memcmp(&si, st, sizeof(StateInfo))) - return false; - } + if (step && ++*step, testKingCount) + if ( std::count(board, board + SQUARE_NB, W_KING) != 1 + || std::count(board, board + SQUARE_NB, B_KING) != 1) + return false; - if (step == Lists) - for (Color c = WHITE; c <= BLACK; ++c) - for (PieceType pt = PAWN; pt <= KING; ++pt) - { - if (pieceCount[c][pt] != popcount(pieces(c, pt))) - return false; + if (step && ++*step, testKingCapture) + if (attackers_to(king_square(~sideToMove)) & pieces(sideToMove)) + return false; - for (int i = 0; i < pieceCount[c][pt]; ++i) - if ( board[pieceList[c][pt][i]] != make_piece(c, pt) - || index[pieceList[c][pt][i]] != i) - return false; - } - - if (step == Castling) - for (Color c = WHITE; c <= BLACK; ++c) - for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1)) - { - if (!can_castle(c | s)) - continue; - - if ( piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK) - || castlingRightsMask[castlingRookSquare[c | s]] != (c | s) - ||(castlingRightsMask[king_square(c)] & (c | s)) != (c | s)) + if (step && ++*step, testPieceCounts) + for (Color c = WHITE; c <= BLACK; ++c) + for (PieceType pt = PAWN; pt <= KING; ++pt) + if (pieceCount[c][pt] != popcount(pieces(c, pt))) + return false; + + if (step && ++*step, testPieceList) + for (Color c = WHITE; c <= BLACK; ++c) + for (PieceType pt = PAWN; pt <= KING; ++pt) + for (int i = 0; i < pieceCount[c][pt]; ++i) + if ( board[pieceList[c][pt][i]] != make_piece(c, pt) + || index[pieceList[c][pt][i]] != i) return false; - } - } + + if (step && ++*step, testCastlingSquares) + for (Color c = WHITE; c <= BLACK; ++c) + for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1)) + { + if (!can_castle(c | s)) + continue; + + if ( (castlingRightsMask[king_square(c)] & (c | s)) != (c | s) + || piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK) + || castlingRightsMask[castlingRookSquare[c | s]] != (c | s)) + return false; + } return true; }