It’s been a while, but usually you do this because a lot of simd instructions operate more easily on lookup tables like this. You can mask, compare, compute, et

It’s been a while, but usually you do this because a lot of simd instructions operate more easily on lookup tables like this. You can mask, compare, compute, etc. on multiple lanes at the same time against a lookup table. The u8 value you’d produce into each component of a simd vector would be used as a shuffle mask or a gather offset to use the table.