[llvm] [InstCombine] Fix the correctness of missing check reassoc attribute (PR #71277)

[via llvm-commits]

vfdff wrote:

This is hard to fix with a unified approach, and need continuous improvement, such as [PR86428](https://github.com/llvm/llvm-project/pull/86428), so close it now

https://github.com/llvm/llvm-project/pull/71277