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/a9hv4z47v - for intels Block RThroughput: =4.0; for ryzens, Block RThroughput: =2.0
So pick cost of 4.
For store we have:
https://godbolt.org/z/6GfPn1b79 - for intels Block RThroughput: =3.0; for ryzens, Block RThroughput: <=2.0
So pick cost of 3.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.