[PATCH] D92317: [LV] ExtractValue instruction costs

[Florian Hahn via Phabricator via llvm-commits]

fhahn accepted this revision.
fhahn added a comment.
This revision is now accepted and ready to land.

LGTM, we should be able to rely on TTI for the cost. Also handling `InsertValue` as a follow-up would be great!



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Comment at: llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:6858
+    // Assume we need 1 instruction to extract a value from a vector.
+    return 1;
   default:
----------------
SjoerdMeijer wrote:
> fhahn wrote:
> > SjoerdMeijer wrote:
> > > fhahn wrote:
> > > > Better to use `TTI.getVectorInstrCost`? And perhaps also handle `InsertValue`?
> > > Yeah, cheers, will look/do that.
> > Should this also handle `InsertValue` for completeness?
> That doesn't seem to be supported by getInstructionCost, which means it returns -1 for InsertValue, which is probably not what we want. So, I think InsertValue needs a bit looking into, which probably best done separately? Although don't mind doing it part of this....
oh yes, just saw that. Probably best to do it separately.


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