[wtallis]

AVX-512 was a bit of a flop initially, because of how Intel implemented it. AMD's solution doesn't provide quite as much peak throughput for highly-optimized code, but is a better way of providing the flexibility benefits of AVX-512 to the masses without the severe downclocking. There may still be plenty of situations where it would make sense to use 256-bit vectors with AVX-512 instructions, but on Zen 4 there won't be a strong reason to avoid 512-bit vectors where they are useful.