AVX512 has native unsigned integer comparisons instructions, removing
the need to XOR the most-significant-bit with a constant in memory to
use the signed comparison instructions. These instructions only write to
a k-mask register though and need an additional call to `vpmovm2*` to
turn the mask-register into a vector-mask register.
As of Icelake:
`vpcmpu*` is all L3/T1
`vpmovm2d` is L1/T0.33
`vpmovm2{b,w}` is L3/T0.33
As of Zen4:
`vpcmpu*` is all L3/T0.50
`vpmovm2*` is all L1/T0.25
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