[llvm] [InstCombine] Add transforms for `(or/and (icmp eq/ne X,0),(icmp eq/ne X,Pow2OrZero))` (PR #94648)

[Nikita Popov via llvm-commits]

nikic wrote:

Implementation still looks good to me. I think @dtcxzyw's tests should give us a much better answer about whether this canonicalization is problematic or not now :)

https://github.com/llvm/llvm-project/pull/94648