[llvm] KnownBits: refine KnownBits::srem for high-bits (PR #109121)

[Ramkumar Ramachandra via llvm-commits]

artagnon wrote:

> I'm not sure if you can use assume in the tgt for verification, maybe try something like this: https://alive2.llvm.org/ce/z/Ugh-Dq

Thanks, the modified proof is indeed correct, and the fix in the code was easy :)

https://github.com/llvm/llvm-project/pull/109121