// it cannot be backward. If can capture an enemy pawn or if
// there are friendly pawns behind on neighboring files it cannot
// be backward either.
+
bool backward;
- if ( passed
- || isolated
- || chain
- || (pos.attacks_from<PAWN>(s, us) & theirPawns)
- || (ourPawns & behind_bb(us, r) & neighboring_files_bb(f)))
+ if ( (passed | isolated | chain)
+ || (ourPawns & behind_bb(us, r) & neighboring_files_bb(f))
+ || (pos.attacks_from<PAWN>(s, us) & theirPawns))
backward = false;
else
{