[clang] [llvm] [InstCombine] Infer nuw for gep inbounds from base of object (PR #119225)

[Vitaly Buka via llvm-commits]

vitalybuka wrote:

> I think [llvm/llvm-test-suite#190](https://github.com/llvm/llvm-test-suite/pull/190) should fix this issue, but haven't tested on an affected arch.
> 
> I'm a bit worried that we don't have a sanitizer to catch this issue (the negative left shift issue is an unrelated one).

`-fsanitize=local-bounds` is quite related, but I guess InstCombine happens before the check inserted

https://github.com/llvm/llvm-project/pull/119225