[mtklein]

The promise of the AVX-512 instruction set really was that it would be much easier to (auto-)vectorize code that wasn’t written with vectorization in mind, with tools like masked execution and gather/scatter that either didn’t exist at all before (SSE) or were very minimal (AVX).

The tools are there in the instruction set, but that still leaves the issues of time and effort to implement in compilers, and enough performance improvement on enough machines in some market (browsers, games, etc) capable of running it all before any of this possibility becomes real.

The skylake-xeon/icelake false start here really can’t have helped. It’s still a much more pragmatic thing to target the haswell feature set that all the intel chips and most amd chips can run (and run well).