private static boolean checkRegUsed(BitSet regsUsed,RegisterSpec rs){
  int reg=rs.getReg();
  int category=rs.getCategory();
  return regsUsed.get(reg) || (category == 2 ? regsUsed.get(reg + 1) : false);
}

private static boolean checkRegUsed ( BitSet regsUsed , RegisterSpec rs ) { int reg = rs . getReg ( ) ; int category = rs . getCategory ( ) ; return regsUsed . get ( reg ) || ( category == 2 ? regsUsed . get ( reg + 1 ) : false ) ; }
checks to see if the register is used in a bitset , taking into account its category / width .
