How are modern processor instructions exposed to userland?

Sijmen J. Mulder ik at
Wed Jun 19 09:32:54 UTC 2019

Mayuresh Kathe <mayuresh at> wrote:
> Let's think about the AVX-512 instruction introduced with the latest 
> Intel Core i9 Skylake-X processor.
> I wanted to know how one could use such capabilities via regular C.

Unprivileged instructions (like these) are available to all processes.
C compilers can and do already emit them when targeting a CPU that
supports them (see the "-march" flag).

You can also use instrinsics:


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