[llvm-dev] invariant.load metadata semantics

Caldarale, Charles R via llvm-dev llvm-dev at lists.llvm.org
Thu Aug 25 14:12:22 PDT 2016

> From: Hal Finkel [mailto:hfinkel at anl.gov] 
> Subject: Re: [llvm-dev] invariant.load metadata semantics

> > I would expect invariant to indicate that loads reachable from the
> > one marked invariant are guaranteed to read the same value, but that
> > prior ones are not.  This would allow updates to be made to the
> > location of interest up to the point of declared invariance, but not
> > after.

> No, this is a different use case, and we invariant.group/invariant.group.barrier and 
> invariant.start/invariant.end for that.

Good point; I'd forgotten about those.

 - Chuck

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