[llvm] [WIP] Fold (bitwiseop X, (add (not Y), Z)) -> (bitwiseop X, (not (sub Y, Z))). (PR #141476)

[Xu Zhang via llvm-commits]

simonzgx wrote:

> Needs tests

Yes, there are some failed UT that need fixing and some new ones to add. I'm still working on both and will submit soon.

https://github.com/llvm/llvm-project/pull/141476