[PATCH] D53710: [FileCheck] Warn if a prefix is only used in LABEL checks

[Sjoerd Meijer via Phabricator via llvm-commits]

SjoerdMeijer added a comment.

> AMDGPU does this a lot intentionally for a shared label prefix and unique per run like ones for different subtargets

Yep.  Briefly looked at AMDGPU warnings. The very first 4 warnings, in tests `basic-loop.ll`, `basic-call-return.ll`, `bug-vopc-commute.ll`, `call-return-types.ll`, shows I think that they are dodgy tests, but then I see indeed the intentional use of the shared label prefix.

While these are only warnings, which you normally don't see when you run lit, I agree that they are false positives which ideally we shouldn't have.

I am not sure what the solution is yet, i.e. I am not sure (haven't looked at it) if I can distinguish the intentional uses from the dodgy uses. Or thinking out loud: perhaps we should say that `-check-prefix` should really check a prefix, and we introduce `-check-label` to check shared labels...


https://reviews.llvm.org/D53710