X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=77a6d604523f40a841a5f73ba6a2e67e41a760f3;hp=20829da26f782ca52b8fef5c18ba9aced711183c;hb=f35ddb04af2a00bd9facf5b66ec97e4ab28d4480;hpb=049139d025b26a9fbc9cf87f51b578a4fab447cf diff --git a/src/position.cpp b/src/position.cpp index 20829da2..77a6d604 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -52,8 +52,7 @@ Key Position::zobCastle[16]; Key Position::zobMaterial[2][8][16]; Key Position::zobSideToMove; -Value Position::MgPieceSquareTable[16][64]; -Value Position::EgPieceSquareTable[16][64]; +Score Position::PieceSquareTable[16][64]; static bool RequestPending = false; @@ -213,8 +212,7 @@ void Position::from_fen(const string& fen) { st->key = compute_key(); st->pawnKey = compute_pawn_key(); st->materialKey = compute_material_key(); - st->mgValue = compute_value(); - st->egValue = compute_value(); + st->value = compute_value(); st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); st->npMaterial[BLACK] = compute_non_pawn_material(BLACK); } @@ -379,36 +377,35 @@ Bitboard Position::discovered_check_candidates(Color c) const { return hidden_checkers(c); } -/// Position::attacks_to() computes a bitboard containing all pieces which +/// Position::attackers_to() computes a bitboard containing all pieces which /// attacks a given square. -Bitboard Position::attacks_to(Square s) const { +Bitboard Position::attackers_to(Square s) const { - return (pawn_attacks(s, BLACK) & pieces(PAWN, WHITE)) - | (pawn_attacks(s, WHITE) & pieces(PAWN, BLACK)) - | (piece_attacks(s) & pieces(KNIGHT)) - | (piece_attacks(s) & pieces(ROOK, QUEEN)) - | (piece_attacks(s) & pieces(BISHOP, QUEEN)) - | (piece_attacks(s) & pieces(KING)); + return (attacks_from(s, BLACK) & pieces(PAWN, WHITE)) + | (attacks_from(s, WHITE) & pieces(PAWN, BLACK)) + | (attacks_from(s) & pieces(KNIGHT)) + | (attacks_from(s) & pieces(ROOK, QUEEN)) + | (attacks_from(s) & pieces(BISHOP, QUEEN)) + | (attacks_from(s) & pieces(KING)); } -/// Position::piece_attacks_square() tests whether the piece on square f -/// attacks square t. +/// Position::attacks_from() computes a bitboard of all attacks +/// of a given piece put in a given square. -bool Position::piece_attacks_square(Piece p, Square f, Square t) const { +Bitboard Position::attacks_from(Piece p, Square s) const { - assert(square_is_ok(f)); - assert(square_is_ok(t)); + assert(square_is_ok(s)); switch (p) { - case WP: return pawn_attacks_square(f, t, WHITE); - case BP: return pawn_attacks_square(f, t, BLACK); - case WN: case BN: return piece_attacks_square(f, t); - case WB: case BB: return piece_attacks_square(f, t); - case WR: case BR: return piece_attacks_square(f, t); - case WQ: case BQ: return piece_attacks_square(f, t); - case WK: case BK: return piece_attacks_square(f, t); + case WP: return attacks_from(s, WHITE); + case BP: return attacks_from(s, BLACK); + case WN: case BN: return attacks_from(s); + case WB: case BB: return attacks_from(s); + case WR: case BR: return attacks_from(s); + case WQ: case BQ: return attacks_from(s); + case WK: case BK: return attacks_from(s); default: break; } return false; @@ -427,7 +424,7 @@ bool Position::move_attacks_square(Move m, Square s) const { assert(square_is_occupied(f)); - if (piece_attacks_square(piece_on(f), t, s)) + if (bit_is_set(attacks_from(piece_on(f), t), s)) return true; // Move the piece and scan for X-ray attacks behind it @@ -440,38 +437,30 @@ bool Position::move_attacks_square(Move m, Square s) const { // If we have attacks we need to verify that are caused by our move // and are not already existent ones. - return xray && (xray ^ (xray & piece_attacks(s))); + return xray && (xray ^ (xray & attacks_from(s))); } /// Position::find_checkers() computes the checkersBB bitboard, which /// contains a nonzero bit for each checking piece (0, 1 or 2). It -/// currently works by calling Position::attacks_to, which is probably +/// currently works by calling Position::attackers_to, which is probably /// inefficient. Consider rewriting this function to use the last move /// played, like in non-bitboard versions of Glaurung. void Position::find_checkers() { Color us = side_to_move(); - st->checkersBB = attacks_to(king_square(us), opposite_color(us)); + st->checkersBB = attackers_to(king_square(us)) & pieces_of_color(opposite_color(us)); } /// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal -bool Position::pl_move_is_legal(Move m) const { - - // If we're in check, all pseudo-legal moves are legal, because our - // check evasion generator only generates true legal moves. - return is_check() || pl_move_is_legal(m, pinned_pieces(side_to_move())); -} - bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(is_ok()); assert(move_is_ok(m)); assert(pinned == pinned_pieces(side_to_move())); - assert(!is_check()); // Castling moves are checked for legality during move generation. if (move_is_castle(m)) @@ -483,7 +472,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(color_of_piece_on(from) == us); assert(piece_on(king_square(us)) == piece_of_color_and_type(us, KING)); - // En passant captures are a tricky special case. Because they are + // 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 (move_is_ep(m)) @@ -510,7 +499,7 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { // If the moving piece is a king, check whether the destination // square is attacked by the opponent. if (type_of_piece_on(from) == KING) - return !attacks_to(move_to(m), opposite_color(us)); + return !(attackers_to(move_to(m)) & pieces_of_color(opposite_color(us))); // A non-king move is legal if and only if it is not pinned or it // is moving along the ray towards or away from the king. @@ -520,6 +509,32 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { } +/// Position::pl_move_is_evasion() tests whether a pseudo-legal move is a legal evasion + +bool Position::pl_move_is_evasion(Move m, Bitboard pinned) const +{ + assert(is_check()); + + Color us = side_to_move(); + Square from = move_from(m); + Square to = move_to(m); + + // King moves and en-passant captures are verified in pl_move_is_legal() + if (type_of_piece_on(from) == KING || move_is_ep(m)) + return pl_move_is_legal(m, pinned); + + Bitboard target = checkers(); + Square checksq = pop_1st_bit(&target); + + if (target) // double check ? + return false; + + // Our move must be a blocking evasion or a capture of the checking piece + target = squares_between(checksq, king_square(us)) | checkers(); + return bit_is_set(target, to) && pl_move_is_legal(m, pinned); +} + + /// Position::move_is_check() tests whether a pseudo-legal move is a check bool Position::move_is_check(Move m) const { @@ -548,7 +563,7 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const { { case PAWN: - if (bit_is_set(pawn_attacks(ksq, them), to)) // Normal check? + if (bit_is_set(attacks_from(ksq, them), to)) // Normal check? return true; if ( dcCandidates // Discovered check? @@ -564,7 +579,7 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const { switch (move_promotion_piece(m)) { case KNIGHT: - return bit_is_set(piece_attacks(to), ksq); + return bit_is_set(attacks_from(to), ksq); case BISHOP: return bit_is_set(bishop_attacks_bb(to, b), ksq); case ROOK: @@ -594,21 +609,21 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const { // Test discovered check and normal check according to piece type case KNIGHT: return (dcCandidates && bit_is_set(dcCandidates, from)) - || bit_is_set(piece_attacks(ksq), to); + || bit_is_set(attacks_from(ksq), to); case BISHOP: return (dcCandidates && bit_is_set(dcCandidates, from)) - || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks(ksq), to)); + || (direction_is_diagonal(ksq, to) && bit_is_set(attacks_from(ksq), to)); case ROOK: return (dcCandidates && bit_is_set(dcCandidates, from)) - || (direction_is_straight(ksq, to) && bit_is_set(piece_attacks(ksq), to)); + || (direction_is_straight(ksq, to) && bit_is_set(attacks_from(ksq), to)); case QUEEN: // Discovered checks are impossible! assert(!bit_is_set(dcCandidates, from)); - return ( (direction_is_straight(ksq, to) && bit_is_set(piece_attacks(ksq), to)) - || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks(ksq), to))); + return ( (direction_is_straight(ksq, to) && bit_is_set(attacks_from(ksq), to)) + || (direction_is_diagonal(ksq, to) && bit_is_set(attacks_from(ksq), to))); case KING: // Discovered check? @@ -662,22 +677,23 @@ inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square // Direct checks if ( ( (Bishop && bit_is_set(BishopPseudoAttacks[ksq], to)) || (Rook && bit_is_set(RookPseudoAttacks[ksq], to))) - && bit_is_set(piece_attacks(ksq), to)) // slow, try to early skip + && bit_is_set(attacks_from(ksq), to)) // slow, try to early skip set_bit(pCheckersBB, to); else if ( Piece != KING && !Slider - && bit_is_set(Piece == PAWN ? pawn_attacks(ksq, opposite_color(sideToMove)) : piece_attacks(ksq), to)) + && bit_is_set(Piece == PAWN ? attacks_from(ksq, opposite_color(sideToMove)) + : attacks_from(ksq), to)) set_bit(pCheckersBB, to); // Discovery checks if (Piece != QUEEN && bit_is_set(dcCandidates, from)) { if (Piece != ROOK) - (*pCheckersBB) |= (piece_attacks(ksq) & pieces(ROOK, QUEEN, side_to_move())); + (*pCheckersBB) |= (attacks_from(ksq) & pieces(ROOK, QUEEN, side_to_move())); if (Piece != BISHOP) - (*pCheckersBB) |= (piece_attacks(ksq) & pieces(BISHOP, QUEEN, side_to_move())); + (*pCheckersBB) |= (attacks_from(ksq) & pieces(BISHOP, QUEEN, side_to_move())); } } @@ -702,10 +718,10 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // ones which are recalculated from scratch anyway, then switch our state // pointer to point to the new, ready to be updated, state. struct ReducedStateInfo { - Key key, pawnKey, materialKey; - int castleRights, rule50; - Square kingSquare[2], epSquare; - Value mgValue, egValue; + Key pawnKey, materialKey; + int castleRights, rule50, pliesFromNull; + Square epSquare; + Value value; Value npMaterial[2]; }; @@ -724,6 +740,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // Increment the 50 moves rule draw counter. Resetting it to zero in the // case of non-reversible moves is taken care of later. st->rule50++; + st->pliesFromNull++; if (move_is_castle(m)) { @@ -741,16 +758,15 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { Piece piece = piece_on(from); PieceType pt = type_of_piece(piece); + PieceType capture = ep ? PAWN : type_of_piece_on(to); assert(color_of_piece_on(from) == us); assert(color_of_piece_on(to) == them || square_is_empty(to)); assert(!(ep || pm) || piece == piece_of_color_and_type(us, PAWN)); assert(!pm || relative_rank(us, to) == RANK_8); - st->capture = ep ? PAWN : type_of_piece_on(to); - - if (st->capture) - do_capture_move(key, st->capture, them, to, ep); + if (capture) + do_capture_move(key, capture, them, to, ep); // Update hash key key ^= zobrist[us][pt][from] ^ zobrist[us][pt][to]; @@ -784,10 +800,6 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { board[to] = board[from]; board[from] = EMPTY; - // If the moving piece was a king, update the king square - if (pt == KING) - st->kingSquare[us] = to; - // Update piece lists, note that index[from] is not updated and // becomes stale. This works as long as index[] is accessed just // by known occupied squares. @@ -804,9 +816,9 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; // Set en passant square, only if moved pawn can be captured - if (abs(int(to) - int(from)) == 16) + if ((to ^ from) == 16) { - if (pawn_attacks(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them)) + if (attacks_from(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them)) { st->epSquare = Square((int(from) + int(to)) / 2); key ^= zobEp[st->epSquare]; @@ -815,8 +827,10 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { } // Update incremental scores - st->mgValue += pst_delta(piece, from, to); - st->egValue += pst_delta(piece, from, to); + st->value += pst_delta(piece, from, to); + + // Set capture piece + st->capture = capture; if (pm) // promotion ? { @@ -842,6 +856,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { Square lastPawnSquare = pieceList[us][PAWN][pieceCount[us][PAWN]]; index[lastPawnSquare] = index[to]; pieceList[us][PAWN][index[lastPawnSquare]] = lastPawnSquare; + pieceList[us][PAWN][pieceCount[us][PAWN]] = SQ_NONE; index[to] = pieceCount[us][promotion] - 1; pieceList[us][promotion][index[to]] = to; @@ -850,10 +865,8 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { st->pawnKey ^= zobrist[us][PAWN][to]; // Partially revert and update incremental scores - st->mgValue -= pst(us, PAWN, to); - st->mgValue += pst(us, promotion, to); - st->egValue -= pst(us, PAWN, to); - st->egValue += pst(us, promotion, to); + st->value -= pst(us, PAWN, to); + st->value += pst(us, promotion, to); // Update material st->npMaterial[us] += piece_value_midgame(promotion); @@ -864,7 +877,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // Update checkers bitboard, piece must be already moved if (ep | pm) - st->checkersBB = attacks_to(king_square(them), us); + st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); else { st->checkersBB = EmptyBoardBB; @@ -883,9 +896,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) { // Finish sideToMove = opposite_color(sideToMove); - - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); } @@ -921,8 +932,7 @@ void Position::do_capture_move(Bitboard& key, PieceType capture, Color them, Squ key ^= zobrist[them][capture][capsq]; // Update incremental scores - st->mgValue -= pst(them, capture, capsq); - st->egValue -= pst(them, capture, capsq); + st->value -= pst(them, capture, capsq); // If the captured piece was a pawn, update pawn hash key, // otherwise update non-pawn material. @@ -947,6 +957,7 @@ void Position::do_capture_move(Bitboard& key, PieceType capture, Color them, Squ Square lastPieceSquare = pieceList[them][capture][pieceCount[them][capture]]; index[lastPieceSquare] = index[capsq]; pieceList[them][capture][index[lastPieceSquare]] = lastPieceSquare; + pieceList[them][capture][pieceCount[them][capture]] = SQ_NONE; // Reset rule 50 counter st->rule50 = 0; @@ -987,17 +998,22 @@ void Position::do_castle_move(Move m) { rto = relative_square(us, SQ_D1); } - // Move the pieces - Bitboard kmove_bb = make_move_bb(kfrom, kto); - do_move_bb(&(byColorBB[us]), kmove_bb); - do_move_bb(&(byTypeBB[KING]), kmove_bb); - do_move_bb(&(byTypeBB[0]), kmove_bb); // HACK: byTypeBB[0] == occupied squares - - Bitboard rmove_bb = make_move_bb(rfrom, rto); - do_move_bb(&(byColorBB[us]), rmove_bb); - do_move_bb(&(byTypeBB[ROOK]), rmove_bb); - do_move_bb(&(byTypeBB[0]), rmove_bb); // HACK: byTypeBB[0] == occupied squares - + // Remove pieces from source squares: + clear_bit(&(byColorBB[us]), kfrom); + clear_bit(&(byTypeBB[KING]), kfrom); + clear_bit(&(byTypeBB[0]), kfrom); // HACK: byTypeBB[0] == occupied squares + clear_bit(&(byColorBB[us]), rfrom); + clear_bit(&(byTypeBB[ROOK]), rfrom); + clear_bit(&(byTypeBB[0]), rfrom); // HACK: byTypeBB[0] == occupied squares + + // Put pieces on destination squares: + set_bit(&(byColorBB[us]), kto); + set_bit(&(byTypeBB[KING]), kto); + set_bit(&(byTypeBB[0]), kto); // HACK: byTypeBB[0] == occupied squares + set_bit(&(byColorBB[us]), rto); + set_bit(&(byTypeBB[ROOK]), rto); + set_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares + // Update board array Piece king = piece_of_color_and_type(us, KING); Piece rook = piece_of_color_and_type(us, ROOK); @@ -1005,9 +1021,6 @@ void Position::do_castle_move(Move m) { board[kto] = king; board[rto] = rook; - // Update king square - st->kingSquare[us] = kto; - // Update piece lists pieceList[us][KING][index[kfrom]] = kto; pieceList[us][ROOK][index[rfrom]] = rto; @@ -1016,10 +1029,8 @@ void Position::do_castle_move(Move m) { index[rto] = tmp; // Update incremental scores - st->mgValue += pst_delta(king, kfrom, kto); - st->egValue += pst_delta(king, kfrom, kto); - st->mgValue += pst_delta(rook, rfrom, rto); - st->egValue += pst_delta(rook, rfrom, rto); + st->value += pst_delta(king, kfrom, kto); + st->value += pst_delta(rook, rfrom, rto); // Update hash key st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto]; @@ -1041,13 +1052,11 @@ void Position::do_castle_move(Move m) { st->rule50 = 0; // Update checkers BB - st->checkersBB = attacks_to(king_square(them), us); + st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); // Finish sideToMove = opposite_color(sideToMove); - - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); } @@ -1106,10 +1115,12 @@ void Position::undo_move(Move m) { Square lastPromotionSquare = pieceList[us][promotion][pieceCount[us][promotion]]; index[lastPromotionSquare] = index[to]; pieceList[us][promotion][index[lastPromotionSquare]] = lastPromotionSquare; + pieceList[us][promotion][pieceCount[us][promotion]] = SQ_NONE; index[to] = pieceCount[us][PAWN] - 1; pieceList[us][PAWN][index[to]] = to; } + // Put the piece back at the source square Bitboard move_bb = make_move_bb(to, from); do_move_bb(&(byColorBB[us]), move_bb); @@ -1187,17 +1198,22 @@ void Position::undo_castle_move(Move m) { assert(piece_on(kto) == piece_of_color_and_type(us, KING)); assert(piece_on(rto) == piece_of_color_and_type(us, ROOK)); - - // Put the pieces back at the source square - Bitboard kmove_bb = make_move_bb(kto, kfrom); - do_move_bb(&(byColorBB[us]), kmove_bb); - do_move_bb(&(byTypeBB[KING]), kmove_bb); - do_move_bb(&(byTypeBB[0]), kmove_bb); // HACK: byTypeBB[0] == occupied squares - - Bitboard rmove_bb = make_move_bb(rto, rfrom); - do_move_bb(&(byColorBB[us]), rmove_bb); - do_move_bb(&(byTypeBB[ROOK]), rmove_bb); - do_move_bb(&(byTypeBB[0]), rmove_bb); // HACK: byTypeBB[0] == occupied squares + + // Remove pieces from destination squares: + clear_bit(&(byColorBB[us]), kto); + clear_bit(&(byTypeBB[KING]), kto); + clear_bit(&(byTypeBB[0]), kto); // HACK: byTypeBB[0] == occupied squares + clear_bit(&(byColorBB[us]), rto); + clear_bit(&(byTypeBB[ROOK]), rto); + clear_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares + + // Put pieces on source squares: + set_bit(&(byColorBB[us]), kfrom); + set_bit(&(byTypeBB[KING]), kfrom); + set_bit(&(byTypeBB[0]), kfrom); // HACK: byTypeBB[0] == occupied squares + set_bit(&(byColorBB[us]), rfrom); + set_bit(&(byTypeBB[ROOK]), rfrom); + set_bit(&(byTypeBB[0]), rfrom); // HACK: byTypeBB[0] == occupied squares // Update board board[rto] = board[kto] = EMPTY; @@ -1232,9 +1248,9 @@ void Position::do_null_move(StateInfo& backupSt) { // a backup storage not as a new state to be used. backupSt.key = st->key; backupSt.epSquare = st->epSquare; - backupSt.mgValue = st->mgValue; - backupSt.egValue = st->egValue; + backupSt.value = st->value; backupSt.previous = st->previous; + backupSt.pliesFromNull = st->pliesFromNull; st->previous = &backupSt; // Save the current key to the history[] array, in order to be able to @@ -1251,10 +1267,9 @@ void Position::do_null_move(StateInfo& backupSt) { sideToMove = opposite_color(sideToMove); st->epSquare = SQ_NONE; st->rule50++; + st->pliesFromNull = 0; + st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue; gamePly++; - - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; } @@ -1269,9 +1284,9 @@ void Position::undo_null_move() { StateInfo* backupSt = st->previous; st->key = backupSt->key; st->epSquare = backupSt->epSquare; - st->mgValue = backupSt->mgValue; - st->egValue = backupSt->egValue; + st->value = backupSt->value; st->previous = backupSt->previous; + st->pliesFromNull = backupSt->pliesFromNull; // Update the necessary information sideToMove = opposite_color(sideToMove); @@ -1325,7 +1340,7 @@ int Position::see(Square from, Square to) const { 0, 0 }; - Bitboard attackers, stmAttackers, occ, b; + Bitboard attackers, stmAttackers, b; assert(square_is_ok(from) || from == SQ_NONE); assert(square_is_ok(to)); @@ -1337,10 +1352,11 @@ int Position::see(Square from, Square to) const { // Initialize pieces Piece piece = piece_on(from); Piece capture = piece_on(to); + Bitboard occ = occupied_squares(); - // Find all attackers to the destination square, with the moving piece - // removed, but possibly an X-ray attacker added behind it. - occ = occupied_squares(); + // King cannot be recaptured + if (type_of_piece(piece) == KING) + return seeValues[capture]; // Handle en passant moves if (st->epSquare == to && type_of_piece_on(from) == PAWN) @@ -1357,13 +1373,15 @@ int Position::see(Square from, Square to) const { while (true) { + // Find all attackers to the destination square, with the moving piece + // removed, but possibly an X-ray attacker added behind it. clear_bit(&occ, from); - attackers = (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN)) - | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN)) - | (piece_attacks(to) & pieces(KNIGHT)) - | (piece_attacks(to) & pieces(KING)) - | (pawn_attacks(to, WHITE) & pieces(PAWN, BLACK)) - | (pawn_attacks(to, BLACK) & pieces(PAWN, WHITE)); + attackers = (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN)) + | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN)) + | (attacks_from(to) & pieces(KNIGHT)) + | (attacks_from(to) & pieces(KING)) + | (attacks_from(to, WHITE) & pieces(PAWN, BLACK)) + | (attacks_from(to, BLACK) & pieces(PAWN, WHITE)); if (from != SQ_NONE) break; @@ -1478,8 +1496,8 @@ void Position::clear() { for (int i = 0; i < 64; i++) board[i] = EMPTY; - for (int i = 0; i < 7; i++) - for (int j = 0; j < 8; j++) + for (int i = 0; i < 8; i++) + for (int j = 0; j < 16; j++) pieceList[0][i][j] = pieceList[1][i][j] = SQ_NONE; sideToMove = WHITE; @@ -1519,9 +1537,6 @@ void Position::put_piece(Piece p, Square s) { set_bit(&byTypeBB[0], s); // HACK: byTypeBB[0] contains all occupied squares. pieceCount[c][pt]++; - - if (pt == KING) - st->kingSquare[c] = s; } @@ -1616,10 +1631,9 @@ Key Position::compute_material_key() const { /// game and the endgame. These functions are used to initialize the incremental /// scores when a new position is set up, and to verify that the scores are correctly /// updated by do_move and undo_move when the program is running in debug mode. -template -Value Position::compute_value() const { +Score Position::compute_value() const { - Value result = Value(0); + Score result = make_score(0, 0); Bitboard b; Square s; @@ -1631,12 +1645,11 @@ Value Position::compute_value() const { { s = pop_1st_bit(&b); assert(piece_on(s) == piece_of_color_and_type(c, pt)); - result += pst(c, pt, s); + result += pst(c, pt, s); } } - const Value TempoValue = (Phase == MidGame ? TempoValueMidgame : TempoValueEndgame); - result += (side_to_move() == WHITE)? TempoValue / 2 : -TempoValue / 2; + result += (side_to_move() == WHITE ? TempoValue / 2 : -TempoValue / 2); return result; } @@ -1680,7 +1693,7 @@ bool Position::is_draw() const { return true; // Draw by repetition? - for (int i = 2; i < Min(gamePly, st->rule50); i += 2) + for (int i = 2; i < Min(Min(gamePly, st->rule50), st->pliesFromNull); i += 2) if (history[gamePly - i] == st->key) return true; @@ -1694,8 +1707,7 @@ bool Position::is_draw() const { bool Position::is_mate() const { MoveStack moves[256]; - - return is_check() && (generate_evasions(*this, moves, pinned_pieces(sideToMove)) == moves); + return is_check() && (generate_moves(*this, moves, false) == moves); } @@ -1716,11 +1728,10 @@ bool Position::has_mate_threat(Color c) { MoveStack mlist[120]; bool result = false; - Bitboard dc = discovered_check_candidates(sideToMove); Bitboard pinned = pinned_pieces(sideToMove); // Generate pseudo-legal non-capture and capture check moves - MoveStack* last = generate_non_capture_checks(*this, mlist, dc); + MoveStack* last = generate_non_capture_checks(*this, mlist); last = generate_captures(*this, last); // Loop through the moves, and see if one of them is mate @@ -1787,16 +1798,12 @@ void Position::init_piece_square_tables() { for (Piece p = WP; p <= WK; p++) { i = (r == 0)? 0 : (genrand_int32() % (r*2) - r); - MgPieceSquareTable[p][s] = Value(MgPST[p][s] + i); - EgPieceSquareTable[p][s] = Value(EgPST[p][s] + i); + PieceSquareTable[p][s] = make_score(MgPST[p][s] + i, EgPST[p][s] + i); } for (Square s = SQ_A1; s <= SQ_H8; s++) for (Piece p = BP; p <= BK; p++) - { - MgPieceSquareTable[p][s] = -MgPieceSquareTable[p-8][flip_square(s)]; - EgPieceSquareTable[p][s] = -EgPieceSquareTable[p-8][flip_square(s)]; - } + PieceSquareTable[p][s] = -PieceSquareTable[p-8][flip_square(s)]; } @@ -1851,8 +1858,7 @@ void Position::flipped_copy(const Position& pos) { st->materialKey = compute_material_key(); // Incremental scores - st->mgValue = compute_value(); - st->egValue = compute_value(); + st->value = compute_value(); // Material st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); @@ -1923,7 +1929,7 @@ bool Position::is_ok(int* failedStep) const { Color us = side_to_move(); Color them = opposite_color(us); Square ksq = king_square(them); - if (attacks_to(ksq, us)) + if (attackers_to(ksq) & pieces_of_color(us)) return false; } @@ -1979,14 +1985,8 @@ bool Position::is_ok(int* failedStep) const { // Incremental eval OK? if (failedStep) (*failedStep)++; - if (debugIncrementalEval) - { - if (st->mgValue != compute_value()) - return false; - - if (st->egValue != compute_value()) - return false; - } + if (debugIncrementalEval && st->value != compute_value()) + return false; // Non-pawn material OK? if (failedStep) (*failedStep)++; @@ -2014,7 +2014,7 @@ bool Position::is_ok(int* failedStep) const { for(PieceType pt = PAWN; pt <= KING; pt++) for(int i = 0; i < pieceCount[c][pt]; i++) { - if (piece_on(piece_list(c, pt, i)) != (pieces(pt, c))) + if (piece_on(piece_list(c, pt, i)) != piece_of_color_and_type(c, pt)) return false; if (index[piece_list(c, pt, i)] != i)