https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94962
--- Comment #5 from Nemo <n...@self-evident.org> ---
(In reply to Jakub Jelinek from comment #2)
I would be happy if GCC could just emit optimal code (single vcmpeqd
instruction) for this useful constant:
_mm256_set_m128i(_mm_setzero_si128(), _mm_set1_epi8(-1))
aka.
_mm256_inserti128_si256(_mm256_setzero_si256(), _mm_set1_epi8(-1), 0)
(The latter is just what GCC uses to implement _mm256_zextsi128_si256, if I am
reading the headers correctly.)
It's a minor thing, but I was a little surprised to find that none of the
compilers I know of are able to do this. At least, not with any input I tried.
