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[X86][Costmodel] Load/store i32/f32 Stride=2 VF=32 interleaving costs
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Authored by lebedev.ri on Sep 29 2021, 12:48 PM.

Details

Summary

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

Here for store pattern we are starting to have spilling,
so accurate modelling may be problematic,
although if i drop the spilling, the measurements don't change.

For load we have:
https://godbolt.org/z/1oTTnncbx - for intels Block RThroughput: =16.0; for ryzens, Block RThroughput: <=8.0
So pick cost of 16.

For store we have:
https://godbolt.org/z/1oTTnncbx - for intels Block RThroughput: =16.0; for ryzens, Block RThroughput: =8.0
So pick cost of 16.

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, 12:48 PM
RKSimon accepted this revision.Oct 1 2021, 6:09 AM

LGTM

This revision is now accepted and ready to land.Oct 1 2021, 6:09 AM

Thank you for the reviews!

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.