* ulong mask A B => A & B
* ulong add A B => A + B (mod 2^32)
* ulong subtract A B => A - B (mod 2^32)
- * ulong compare A B => 0/-1/1
+ * ulong compare A B => 0 -1 (A<B) +1 (A>B)
* ulong shift l|r ULONG BITS fails if BITS >32
*
* ulong ul2bitfields VALUE [SIZE TYPE [TYPE-ARG...] ...] => 0/1