- b1 = ( (pos.piece_attacks<KNIGHT>(checksq) & pos.knights(us))
- | (pos.piece_attacks<BISHOP>(checksq) & pos.bishops_and_queens(us))
- | (pos.piece_attacks<ROOK>(checksq) & pos.rooks_and_queens(us)) ) & ~pinned;
+ b1 = ( (pos.piece_attacks<KNIGHT>(checksq) & pos.pieces(KNIGHT, us))
+ | (pos.piece_attacks<BISHOP>(checksq) & pos.pieces(BISHOP, QUEEN, us))
+ | (pos.piece_attacks<ROOK>(checksq) & pos.pieces(ROOK, QUEEN, us)) ) & ~pinned;