const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB);
const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S);
+ const SquareDelta TDELTA_S = (Us == WHITE ? DELTA_S : DELTA_N);
Bitboard b1, b2, b3;
- Bitboard empty = pos.empty_squares();
Bitboard pawns = pos.pawns(Us);
if (dc & pawns)
{
+ Bitboard empty = pos.empty_squares();
+
// Pawn moves which gives discovered check. This is possible only if the
// pawn is not on the same file as the enemy king, because we don't
// generate captures.
}
// Direct checks. These are possible only for pawns on neighboring files
- // of the enemy king.
+ // and in the two ranks that, after the push, are in front of the enemy king.
b1 = pawns & neighboring_files_bb(ksq) & ~dc;
+ b2 = rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S);
+ b1 &= b2;
+ if (!b1)
+ return mlist;
// Direct checks, single pawn pushes
+ Bitboard empty = pos.empty_squares();
b2 = move_pawns<Us, DELTA_N>(b1) & empty;
b3 = b2 & pos.pawn_attacks(Them, ksq);
while (b3)
// Direct checks
b = target & ~dc;
- if (Piece == KING || !b)
- return mlist;
-
- Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
- if (!checkSqs)
- return mlist;
-
- while (b)
+ if (Piece != KING || b)
{
- Square from = pop_1st_bit(&b);
- if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
- || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs))
- || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
- continue;
+ Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
+ if (!checkSqs)
+ return mlist;
- Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
- SERIALIZE_MOVES(bb);
+ while (b)
+ {
+ Square from = pop_1st_bit(&b);
+ if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
+ || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs))
+ || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
+ continue;
+
+ Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
+ SERIALIZE_MOVES(bb);
+ }
}
return mlist;
}