[PATCH] D139627: clang/X86: Don't emit "min-legal-vector-width"="0"

[Phoebe Wang via Phabricator via llvm-commits]

pengfei requested changes to this revision.
pengfei added a comment.
This revision now requires changes to proceed.

The use of `min-legal-vector-width` doesn't look great to me either. I'm more than glad if we can remove it totally without any user perceivable affects.
I cannot agree with this change because it neither eliminates the clutter (but makes it even worse [1]) nor is NFC to end user.
I think we used `UINT32_MAX` just to be compatible with BCs that generated before introduing the attribute. This change definitely breaks the compatibility.
Placing a `"min-legal-vector-width" = "512"` doesn't make any sense either. For one thing, we cannot place the attribute in pre-built BC files, for another `512` is the current max vector suppoted on X86, we cannot guarantee no `1024`, `2048` etc. in future and we cannot change it too once compiled into BC files.


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  https://reviews.llvm.org/D139627/new/

https://reviews.llvm.org/D139627