[llvm] [HashRecognize] Rewrite arePHIsIntertwined (PR #144878)

[Piotr Fusik via llvm-commits]

pfusik wrote:

Now I think the XOR might be e.g. multiplied by a (runtime) zero, or be one of the branches of a `SelectInst` that is never taken.

https://github.com/llvm/llvm-project/pull/144878