X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=7d7a0641f91f88240a9e6b1ab34f91e014fa8753;hp=22c17173c5727cd016a0bca109f7c2f62cc9c3a7;hb=81e242a96dcfc109aa6dd851a055f49bc7a270db;hpb=2097cd12217a0e18c59bd88424ca613572e6feb2 diff --git a/src/position.cpp b/src/position.cpp index 22c17173..7d7a0641 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -41,7 +41,7 @@ static const string PieceToChar(" PNBRQK pnbrqk"); CACHE_LINE_ALIGNMENT -Score pieceSquareTable[PIECE_NB][SQUARE_NB]; +Score pieceSquareTable[COLOR_NB][PIECE_TYPE_NB][SQUARE_NB]; Value PieceValue[PHASE_NB][PIECE_NB] = { { VALUE_ZERO, PawnValueMg, KnightValueMg, BishopValueMg, RookValueMg, QueenValueMg }, { VALUE_ZERO, PawnValueEg, KnightValueEg, BishopValueEg, RookValueEg, QueenValueEg } }; @@ -94,8 +94,8 @@ void init() { for (Square s = SQ_A1; s <= SQ_H8; s++) { - pieceSquareTable[make_piece(WHITE, pt)][ s] = (v + PSQT[pt][s]); - pieceSquareTable[make_piece(BLACK, pt)][~s] = -(v + PSQT[pt][s]); + pieceSquareTable[WHITE][pt][ s] = (v + PSQT[pt][s]); + pieceSquareTable[BLACK][pt][~s] = -(v + PSQT[pt][s]); } } } @@ -105,9 +105,9 @@ void init() { namespace { -/// next_attacker() is an helper function used by see() to locate the least -/// valuable attacker for the side to move, remove the attacker we just found -/// from the 'occupied' bitboard and scan for new X-ray attacks behind it. +// next_attacker() is an helper function used by see() to locate the least +// valuable attacker for the side to move, remove the attacker we just found +// from the 'occupied' bitboard and scan for new X-ray attacks behind it. template FORCE_INLINE PieceType next_attacker(const Bitboard* bb, const Square& to, const Bitboard& stmAttackers, @@ -408,8 +408,8 @@ const string Position::pretty(Move move) const { ss << square_to_string(pop_lsb(&b)) << " "; ss << "\nLegal moves: "; - for (MoveList ml(*this); !ml.end(); ++ml) - ss << move_to_san(*const_cast(this), ml.move()) << " "; + for (MoveList it(*this); *it; ++it) + ss << move_to_san(*const_cast(this), *it) << " "; return ss.str(); } @@ -747,17 +747,17 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI Color them = ~us; Square from = from_sq(m); Square to = to_sq(m); - Piece piece = piece_on(from); - PieceType pt = type_of(piece); + Piece pc = piece_on(from); + PieceType pt = type_of(pc); PieceType capture = type_of(m) == ENPASSANT ? PAWN : type_of(piece_on(to)); - assert(color_of(piece) == us); + assert(color_of(pc) == us); assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == them || type_of(m) == CASTLE); assert(capture != KING); if (type_of(m) == CASTLE) { - assert(piece == make_piece(us, KING)); + assert(pc == make_piece(us, KING)); bool kingSide = to > from; Square rfrom = to; // Castle is encoded as "king captures friendly rook" @@ -767,7 +767,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI do_castle(from, to, rfrom, rto); - st->psqScore += psq_delta(make_piece(us, ROOK), rfrom, rto); + st->psqScore += pieceSquareTable[us][ROOK][rto] - pieceSquareTable[us][ROOK][rfrom]; k ^= Zobrist::psq[us][ROOK][rfrom] ^ Zobrist::psq[us][ROOK][rto]; } @@ -820,7 +820,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI prefetch((char*)thisThread->materialTable[st->materialKey]); // Update incremental scores - st->psqScore -= pieceSquareTable[make_piece(them, capture)][capsq]; + st->psqScore -= pieceSquareTable[them][capture][capsq]; // Reset rule 50 counter st->rule50 = 0; @@ -856,7 +856,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI byColorBB[us] ^= from_to_bb; board[from] = NO_PIECE; - board[to] = piece; + board[to] = pc; // Update piece lists, index[from] is not updated and becomes stale. This // works as long as index[] is accessed just by known occupied squares. @@ -903,8 +903,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI ^ Zobrist::psq[us][PAWN][pieceCount[us][PAWN]]; // Update incremental score - st->psqScore += pieceSquareTable[make_piece(us, promotion)][to] - - pieceSquareTable[make_piece(us, PAWN)][to]; + st->psqScore += pieceSquareTable[us][promotion][to] - pieceSquareTable[us][PAWN][to]; // Update material st->npMaterial[us] += PieceValue[MG][promotion]; @@ -919,7 +918,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI } // Update incremental scores - st->psqScore += psq_delta(piece, from, to); + st->psqScore += pieceSquareTable[us][pt][to] - pieceSquareTable[us][pt][from]; // Set capture piece st->capturedType = capture; @@ -1129,10 +1128,10 @@ void Position::undo_null_move() { /// 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 -/// move, and one which takes a 'from' and a 'to' square. The function does -/// not yet understand promotions captures. +/// material gain or loss resulting from a move. Parameter 'asymmThreshold' takes +/// tempi into account. If the side who initiated the capturing sequence does the +/// last capture, he loses a tempo and if the result is below 'asymmThreshold' +/// the capturing sequence is considered bad. int Position::see_sign(Move m) const { @@ -1147,17 +1146,7 @@ int Position::see_sign(Move m) const { return see(m); } -int Position::see(Move m) const { - return do_see(m, 0); -} - -int Position::see_asymm(Move m, int asymmThreshold) const -{ - return do_see(m, asymmThreshold); -} - -template -int Position::do_see(Move m, int asymmThreshold) const { +int Position::see(Move m, int asymmThreshold) const { Square from, to; Bitboard occupied, attackers, stmAttackers; @@ -1234,15 +1223,14 @@ int Position::do_see(Move m, int asymmThreshold) const { } while (stmAttackers); - // FIXME: Document - if (Asymmetric) - { - for (int i = 0; i < slIndex ; slIndex += 2) - { - if (swapList[slIndex] < asymmThreshold) - swapList[slIndex] = - QueenValueMg * 16; - } - } + // If we are doing asymmetric SEE evaluation and the same side does the first + // and the last capture, he loses a tempo and gain must be at least worth + // 'asymmThreshold', otherwise we replace the score with a very low value, + // before negamaxing. + if (asymmThreshold) + for (int i = 0; i < slIndex; i += 2) + if (swapList[i] < asymmThreshold) + swapList[i] = - QueenValueMg * 16; // 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. @@ -1361,7 +1349,8 @@ Score Position::compute_psq_score() const { for (Bitboard b = pieces(); b; ) { Square s = pop_lsb(&b); - score += pieceSquareTable[piece_on(s)][s]; + Piece pc = piece_on(s); + score += pieceSquareTable[color_of(pc)][type_of(pc)][s]; } return score; @@ -1387,7 +1376,6 @@ 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 bool Position::is_draw() const { // Draw by material? @@ -1400,33 +1388,26 @@ bool Position::is_draw() const { return true; // Draw by repetition? - if (!SkipRepetition) - { - int i = 4, e = std::min(st->rule50, st->pliesFromNull); + int i = 4, e = std::min(st->rule50, st->pliesFromNull); - if (i <= e) - { - StateInfo* stp = st->previous->previous; + if (i <= e) + { + StateInfo* stp = st->previous->previous; - do { - stp = stp->previous->previous; + do { + stp = stp->previous->previous; - if (stp->key == st->key) - return true; + if (stp->key == st->key) + return true; - i += 2; + i += 2; - } while (i <= e); - } + } while (i <= e); } return false; } -// Explicit template instantiations -template bool Position::is_draw() const; -template bool Position::is_draw() const; - /// Position::flip() flips position with the white and black sides reversed. This /// is only useful for debugging especially for finding evaluation symmetry bugs.