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[X86][Costmodel] Load/store i32/f32 Stride=6 VF=16 interleaving costs
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Authored by lebedev.ri on Oct 4 2021, 12:21 PM.

Details

Summary

This one required quite a bit of an assembly surgery, but i think it's in the right ballpark..

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

For load we have:
https://godbolt.org/z/na97Kb96o - for intels Block RThroughput: <=64.0; for ryzens, Block RThroughput: <=32.0
So could pick cost of 64.

For store we have:
https://godbolt.org/z/GG1WeoKar - for intels Block RThroughput: =66.0; for ryzens, Block RThroughput: <=27.5
So we could pick cost of 66.

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.Oct 4 2021, 12:21 PM
lebedev.ri edited the summary of this revision. (Show Details)Oct 4 2021, 12:59 PM
RKSimon accepted this revision.Oct 5 2021, 6:20 AM

LGTM

This revision is now accepted and ready to land.Oct 5 2021, 6:20 AM

LGTM

Thank you for the reviews!

This revision was landed with ongoing or failed builds.Oct 5 2021, 7:00 AM
This revision was automatically updated to reflect the committed changes.