[PATCH] D72742: Don't assume promotable integers are zero/sign-extended already in x86-64 ABI.

Emilio Cobos Álvarez via Phabricator via cfe-commits cfe-commits at lists.llvm.org
Mon Feb 3 05:32:57 PST 2020


emilio added a comment.

Could anyone update me with how do they want me to proceed here? Is fixing the coercions enough to allow this to land? Do I need to make it target-specific? If so, which targets should keep the current behavior?

Another slightly more backwards-compatible alternative (though hacky, arguably) is to just not use the zext for optimization purposes in the backend. This would be simpler and should keep clang always sign-extending on the caller too, for now. We could then after a while, switch to this approach. D71178 <https://reviews.llvm.org/D71178> contains such a patch, for comparison.

Thoughts?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72742/new/

https://reviews.llvm.org/D72742





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