Assuming 2's complement is used for signed numbers, operations that care about signedness (ie they are different for the signed and unsigned interpretation of a bitstring) are:
- division
- modulo
- right shift
- comparisons (except equality)
- double-width multiplication (rare outside of assembly)
Operations for which signedness is irrelevant are:
- addition
- subtraction
- negation (
-x
means~x + 1
) - bitwise and
- bitwise or
- bitwise xor
- bitwise not (
~x
means-x - 1
) - left shift
- multiplication
- comparison (equality only)