[llvm] [InstCombine] Propagate exact flags in transformation (PR #88340)

[via llvm-commits]

AtariDreams wrote:

> Could you please please add alive2 proof for it?

https://alive2.llvm.org/ce/z/kspgi5

> @AtariDreams Your contribution behavior continues to be unacceptable, to the point that I am _this close_ to requesting a ban from the LLVM organization for you.
> 
> Please, do not submit pull requests until you both have adequate test coverage and proofs. See https://llvm.org/docs/InstCombineContributorGuide.html for our contribution guidelines. If you want to submit a PR without these things, submit it as a draft pull request, and only mark it as ready for review when it is actually ready.

I apologize. I will ensure moving forward to ensure all PRs have proofs and tests.

https://github.com/llvm/llvm-project/pull/88340