[PATCH] D132308: [LV] Replace fixed-order cost model with a SK_Splice shuffle

Mon Aug 22 02:59:31 PDT 2022

fhahn added a subscriber: power-llvm-team.
fhahn added a comment.

Using splice seems more accurate here, thanks! It would be good to update at least X86 before landing this.

Also cc'ing @power-llvm-team and @jonpa  for the PPC & SystemZ costs respectively.

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Comment at: llvm/test/Transforms/LoopVectorize/ARM/mve-recurrence.ll:10

 define void @firstorderrec(ptr nocapture noundef readonly %x, ptr noalias nocapture noundef writeonly %y, i32 noundef %n) #0 {
 ; CHECK-LABEL: @firstorderrec(
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It would probably be good to have the same test for X86 and AArch64 at least. THere's seems no cost-model test for recurrences on X86 at all, and on AArch64 we only have first-order recurrences.

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  https://reviews.llvm.org/D132308/new/

https://reviews.llvm.org/D132308