[PATCH] D155459: [AArch64] Change the cost of vector insert/extract to 2

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


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Comment at: llvm/test/Transforms/LoopVectorize/AArch64/strict-fadd-cost.ll:53
 ; CHECK-VF4: Found an estimated cost of 1 for VF 4 For instruction:   %muladd = tail call float @llvm.fmuladd.f32(float %0, float %1, float %sum.07)
-; CHECK-VF8: Found an estimated cost of 38 for VF 8 For instruction:   %muladd = tail call float @llvm.fmuladd.f32(float %0, float %1, float %sum.07)
+; CHECK-VF8: Found an estimated cost of 32 for VF 8 For instruction:   %muladd = tail call float @llvm.fmuladd.f32(float %0, float %1, float %sum.07)
 
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efriedma wrote:
> dmgreen wrote:
> > efriedma wrote:
> > > This cost modeling is weird.
> > This is an in-order reduction.
> Then why does it cost 1 at VF 4?
It, for some reason, prints the costs twice and these are matching two different things. There is some details in 2e0bf67df1437cb0156d7f5dd9e1b701749f96ca. I'll rebased on the updated costs.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D155459/new/

https://reviews.llvm.org/D155459