[Bug target/80636] AVX / AVX512 register-zeroing should always use AVX 128b, not ymm or zmm

2021-06-03 Thread peter at cordes dot ca via Gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80636 Peter Cordes changed: What|Removed |Added Status|NEW |RESOLVED Resolution|---

[Bug target/80636] AVX / AVX512 register-zeroing should always use AVX 128b, not ymm or zmm

2017-05-20 Thread peter at cordes dot ca
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80636 --- Comment #3 from Peter Cordes --- The point about moves also applies to integer code, since a 64-bit mov requires an extra byte for the REX prefix (unless a REX prefix was already required for r8-r15). I just noticed a case where gcc uses a

[Bug target/80636] AVX / AVX512 register-zeroing should always use AVX 128b, not ymm or zmm

2017-05-05 Thread peter at cordes dot ca
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80636 --- Comment #2 from Peter Cordes --- > The same possibly applies to all "zero-extending" moves? Yes, if a vmovdqa %xmm0,%xmm1 will work, it's the best choice on AMD CPUs, and doesn't hurt on Intel CPUs. So in any case where you need to copy

[Bug target/80636] AVX / AVX512 register-zeroing should always use AVX 128b, not ymm or zmm

2017-05-05 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80636 Richard Biener changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed|