[llvm] InstCombine: improve optimizations for ceiling division with no overflow (PR #142869)

[Alex Gaynor via llvm-commits]

alex wrote:

https://alive2.llvm.org/ce/z/HRxA3c generalized proof for all integer powers of 2. Hopefully that looks good.

Will work on your code review notes next. Thank you!

https://github.com/llvm/llvm-project/pull/142869