Just to clarify - this was about SWAR version as my interest, similar to what you mentioned in a sibling comment, is in mainly below-vector-width strings, becau

Just to clarify - this was about SWAR version as my interest, similar to what you mentioned in a sibling comment, is in mainly below-vector-width strings, because these are most frequently passed to these kinds of functions by developers. I was going to try to see if it can further "amortize" the jump table with fallthrough for variable lengths below 16 in my C# UTF-8 string implementation that is going to use it. In any case, thanks for writing the article, for some reason there is quite a bit of negativity among users and developers towards AVX512 - it is seen as "AVX2 but twice as wide", which it of course isn't, but most do not know that. Also, you may want to simply do the overlapping conversion for the tail instead of masking out the elements, which is usually faster on the benchmarks (at least give it a try), and also align the source and destination for the loop to avoid split loads/stores.