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[X86][Costmodel] Load/store i64/f64 Stride=3 VF=4 interleaving costs
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Authored by lebedev.ri on Oct 3 2021, 8:13 AM.

Details

Summary

This one required quite a bit of assembly surgery.

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/Tce3osvcz - for intels Block RThroughput: =5.0; for ryzens, Block RThroughput: <=4.0
So pick cost of 5.

For store we have:
https://godbolt.org/z/oc3arEcnE - for intels Block RThroughput: =6.0; for ryzens, Block RThroughput: <=4.0
So pick cost of 6.

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

Diff Detail