[PATCH] D21271: Fix `InstCombine` to not widen metadata on store-to-load forwarding

[Anna Thomas via llvm-commits]

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anna added a comment.

Could you please add a comment explaining the new parameter `isLoadCSE` same as done for other parameters in `FindAvailableLoadedValue`, and what's the purpose of recording the fact that it's a load. It's not very obvious by looking at the change in the code in InstCombineLoadStoreAlloca.cpp.

This way other optimizations using `FindAvailableLoadedValue` can *correctly* use this hidden parameter, `isLoadCSE`.

I agree with @deadalnix can we fix the issue of missing metadata without using hidden parameters, and adding to the list of parameters kept track to `FindAvailableLoadedValue`?


http://reviews.llvm.org/D21271