[llvm] [SeparateConstOffsetFromGEP] Decompose constant xor operand if possible (PR #135788)

[Sumanth Gundapaneni via llvm-commits]

sgundapa wrote:

> Do you mean cases like the add 0, 0 from the tests?

I added this  (add 0,0) as a short cut for the knownbits to compute bits easily. I can rewrite them with variable, and, or to set the values i need. 



https://github.com/llvm/llvm-project/pull/135788