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/v98qPTTf6 - for intels Block RThroughput: =18.0; for ryzens, Block RThroughput: =6.0
So pick cost of 18.
For store we have:
https://godbolt.org/z/rn5T9E8q6 - for intels Block RThroughput: <=16.0; for ryzens, Block RThroughput: <=4.5
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.