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[X86][Costmodel] Load/store i64/f64 Stride=2 VF=8 interleaving costs
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Authored by lebedev.ri on Sep 30 2021, 8:04 AM.

Details

Summary

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/PGYbYKPq8 - for intels Block RThroughput: =8.0; for ryzens, Block RThroughput: <=4.0
So pick cost of 8.

For store we have:
https://godbolt.org/z/PGYbYKPq8 - for intels Block RThroughput: =8.0; for ryzens, Block RThroughput: <=8.0
So pick cost of 8.

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 30 2021, 8:04 AM
RKSimon accepted this revision.Oct 1 2021, 5:44 AM

LGTM

This revision is now accepted and ready to land.Oct 1 2021, 5:44 AM
This revision was landed with ongoing or failed builds.Oct 1 2021, 7:49 AM
This revision was automatically updated to reflect the committed changes.