X86FSET_SSE4_2
if (!is_x86_feature(x86_featureset, X86FSET_SSE4_2)) {
add_x86_feature(featureset, X86FSET_SSE4_2);
{ AV_386_SSE4_2, X86FSET_SSE4_2 },
is_x86_feature(x86_featureset, X86FSET_SSE4_2)) {