Hey, you can have 7-bit lookup tables at the byte level on AVX512VBMI (using the 2-register shuffle forms) and you can already have 6-bit lookups with 2-register 16-bit shuffles if you can play around on Skylake Server.
Mass availability of the VBMI goodies looks to be bottlenecked behind Icelake/Sunny Cove, so you'll have plenty of time to think through the implications of fast 6-bit lookup. :-)
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And now I'm distracted looking for 6-bit lookup tables that will enjoy that instruction. DES had 6-bit SBoxes for example.
https://en.wikipedia.org/wiki/DES_supplementary_material#Sub...
Hmmmmm... 6-bit lookup tables. Yum. I wonder what else is out there that would benefit?
Hey, you can have 7-bit lookup tables at the byte level on AVX512VBMI (using the 2-register shuffle forms) and you can already have 6-bit lookups with 2-register 16-bit shuffles if you can play around on Skylake Server.
Mass availability of the VBMI goodies looks to be bottlenecked behind Icelake/Sunny Cove, so you'll have plenty of time to think through the implications of fast 6-bit lookup. :-)