- if ( dcCandidates // Discovered check?
- && bit_is_set(dcCandidates, from)
- && (direction_between_squares(from, ksq) != direction_between_squares(to, ksq)))
- return true;
-
- if (move_is_promotion(m)) // Promotion with check?
- {
- Bitboard b = occupied_squares();
- clear_bit(&b, from);
-
- switch (move_promotion_piece(m))
- {
- case KNIGHT:
- return bit_is_set(attacks_from<KNIGHT>(to), ksq);
- case BISHOP:
- return bit_is_set(bishop_attacks_bb(to, b), ksq);
- case ROOK:
- return bit_is_set(rook_attacks_bb(to, b), ksq);
- case QUEEN:
- return bit_is_set(queen_attacks_bb(to, b), ksq);
- default:
- assert(false);
- }
- }
- // 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.
- else if (move_is_ep(m))
- {
- Square capsq = make_square(square_file(to), square_rank(from));
- Bitboard b = occupied_squares();
- clear_bit(&b, from);
- clear_bit(&b, capsq);
- set_bit(&b, to);
- return (rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, us))
- ||(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us));
- }