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[X86][Costmodel] Load/store i8 Stride=2 VF=8 interleaving costs
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Authored by lebedev.ri on Sep 29 2021, 5:57 AM.

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Summary

The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3

Identical to VF=2.

For load we have:
https://godbolt.org/z/4TEbdzbMM - for intels Block RThroughput: =2.0; for ryzens, Block RThroughput: <=1.0
So pick cost of 2.

For store we have:
https://godbolt.org/z/MYfzGPf3Y - for intels Block RThroughput: =1.0; for ryzens, Block RThroughput: <=0.5
So pick cost of 1.

I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.

Diff Detail

Event Timeline

lebedev.ri created this revision.Sep 29 2021, 5:57 AM
RKSimon accepted this revision.Sep 29 2021, 9:18 AM

LGTM

This revision is now accepted and ready to land.Sep 29 2021, 9:18 AM
This revision was landed with ongoing or failed builds.Sep 29 2021, 11:53 AM
This revision was automatically updated to reflect the committed changes.