// note this fails on some x86 machines, with an error like:
#include <simde/x86/mmx.h>
// /usr/lib/gcc/x86_64-redhat-linux/8/include/gfniintrin.h:57:1: error: inlining failed in call to always_inline ‘_mm_gf2p8affine_epi64_epi8’: target specific option mismatch