[llvm] [InstCombine] Handle ceil division idiom (PR #100977)

[Yingwei Zheng via llvm-commits]

dtcxzyw wrote:

> Unless I'm missing something, ValueTracking seems to be lacking support of considering the possible overflow coming from *.with.overflow intrinsics, as computeOverflow currently returns MayOverflow when is guaranteed not to overflow. I'll be taking a look.

Yeah, ValueTracking doesn't support this assumption. It only exists in some rust applications. See also https://github.com/rust-lang/hashbrown/issues/509.



https://github.com/llvm/llvm-project/pull/100977