[PATCH] D150646: [clang][X86] Add __cpuidex function to cpuid.h

[Aiden Grossman via Phabricator via cfe-commits]

aidengrossman added a comment.

The main issue here is that there's no way to reliably detect whether the built in is defined (can't check if a function is defined in the preprocessor, preprocessor macro isn't exposed correctly in all configurations), which ends up breaking some configurations. I wouldn't be opposed to exposing things more often, but I'm fine with the builtins being exposed under `-fms-extensions`, we just need to expose the preprocessor macro when we expose the builtins.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D150646/new/

https://reviews.llvm.org/D150646