[PATCH] D53889: [CodeGen] Prefer static frame index for STATEPOINT liveness args

[Cherry Zhang via Phabricator via llvm-commits]

cherry added a comment.

I think the argument, as an SSA Value, should be immutable. But here, argument at fixed frame index is, in the IR level, a pointer argument with byval attribute. We don't modify the pointer. A function could modify the content of the memory that argument points to, just like a regular pointer argument. The only difference is that we know the pointer points to a fixed stack location.

If the GC were to modify the content of the pointed-to memory, it would do it with or without this change. So I don't think this change affects that.

I tried Option 1. It works, thanks!

I also got another approach, which handles arguments at fixed stack locations more general in getValue. See https://reviews.llvm.org/D55072. I have to tweak some tests slightly. Let me know which one do you think is better. Thanks!


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https://reviews.llvm.org/D53889