[PATCH] D50665: [LV][LAA] Vectorize loop invariant values stored into loop invariant address

[Hideki Saito via Phabricator via llvm-commits]

hsaito added a comment.

In https://reviews.llvm.org/D50665#1208026, @anna wrote:

> In https://reviews.llvm.org/D50665#1206780, @Ayal wrote:
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> > In https://reviews.llvm.org/D50665#1200509, @anna wrote:
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> > >
> >
> >
> > ...
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> > > Yes, the stores are scalarized. Identical replicas left as-is. Either passes such as load elimination can remove it, or we can clean it up in LV itself.
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> >
> >
> > - - by revisiting LoopVectorizationCostModel::collectLoopUniforms()?  ;-)
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>
> Right now, I just run instcombine after loop vectorization to clean up those unnecessary stores (and test cases make sure there's only one store left). Looks like there are other places in LV which relies on InstCombine as the clean up pass, so it may not be that bad after all? Thoughts?


Ideally, each optimizer should generate as clean output IR as it can feasibly do so. Cleaning up this particular "mess" is one of the simpler tasks LV can do on its own.


Repository:
  rL LLVM

https://reviews.llvm.org/D50665