[llvm] [MergeFuncs] Account for elementwise loads in FunctionComparator (PR #211478)

[Yonah Goldberg via llvm-commits]

https://github.com/YonahGoldberg commented:

good catch! I think you should just include the fix for atomicrmw here. ping me when you do and I'll approve quickly

https://github.com/llvm/llvm-project/pull/211478