On Sat, Apr 06, 2024 at 12:08:14PM +1300, David Rowley wrote: > Won't Valgrind complain about this? > > +pg_popcount_avx512(const char *buf, int bytes) > > + buf = (const char *) TYPEALIGN_DOWN(sizeof(__m512i), buf); > > + val = _mm512_maskz_loadu_epi8(mask, (const __m512i *) buf);
I haven't been able to generate any complaints, at least with some simple tests. But I see your point. If this did cause such complaints, ISTM we'd just want to add it to the suppression file. Otherwise, I think we'd have to go back to the non-maskz approach (which I really wanted to avoid because of the weird function overhead juggling) or find another way to do a partial load into an __m512i. -- Nathan Bossart Amazon Web Services: https://aws.amazon.com
