[llvm] [X86] Improve FREEZE node elimination for SETCC operations (PR #192362)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

For the generic ISD::SETCC comparisons, we have to be more careful with fp comparisons as certain combos can create poison - are there any nodes that feed into X86ISD::SETCC/CARRY that can still create poison/undef?

https://github.com/llvm/llvm-project/pull/192362