[PATCH] D148806: [SLP]Fix the cost for the extractelements, used in several nodes.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/blending-shuffle-inseltpoison.ll:12
+; CHECK-NEXT:    [[INS2:%.*]] = insertelement <2 x i8> [[INS1]], i8 [[Y1Y1]], i64 1
+; CHECK-NEXT:    ret <2 x i8> [[INS2]]
 ;
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ABataev wrote:
> ABataev wrote:
> > RKSimon wrote:
> > > This doesn't look faster imo
> > It will be fixed after D148801, I hope. Let me commit it and see if it is so
> TTI reports that the cost of vector mul is 4, when the scalar cost is 2 (1x2). 
> llvm-mca reports different numbers - 8 for scalar muls and 1 for vector mul.
> https://godbolt.org/z/azqaMKabr
Thanks for catching that - I'll get it updated


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D148806/new/

https://reviews.llvm.org/D148806