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[X86][Costmodel] Load/store i16 Stride=4 VF=16 interleaving costs
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Authored by lebedev.ri on Sep 27 2021, 5:55 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/Wd9cKab83 - for intels Block RThroughput: =75.0; for ryzens, Block RThroughput: <=29.5
So pick cost of 75. (note that # 32-byte Reload does not affect throughput there.)

For store we have:
https://godbolt.org/z/Wd9cKab83 - for intels Block RThroughput: =32.0; for ryzens, Block RThroughput: <=12.0
So pick cost of 32.

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 27 2021, 5:55 AM
This revision is now accepted and ready to land.Sep 27 2021, 10:01 AM
This revision was landed with ongoing or failed builds.Sep 27 2021, 12:20 PM
This revision was automatically updated to reflect the committed changes.