On Thu, Feb 17, 2022 at 10:49:48AM +0100, Richard Biener via Gcc-patches wrote:
> On Thu, Feb 17, 2022 at 8:52 AM Uros Bizjak via Gcc-patches
> wrote:
> >
> > On Thu, Feb 17, 2022 at 6:25 AM Hongtao Liu via Gcc-patches
> > wrote:
> > >
> > > On Thu, Feb 17, 2022 at 12:26 PM H.J. Lu via Gcc-patche
On Thu, Feb 17, 2022 at 8:52 AM Uros Bizjak via Gcc-patches
wrote:
>
> On Thu, Feb 17, 2022 at 6:25 AM Hongtao Liu via Gcc-patches
> wrote:
> >
> > On Thu, Feb 17, 2022 at 12:26 PM H.J. Lu via Gcc-patches
> > wrote:
> > >
> > > Reading YMM registers with all zero bits needs VZEROUPPER on Sandy B
On Thu, Feb 17, 2022 at 6:25 AM Hongtao Liu via Gcc-patches
wrote:
>
> On Thu, Feb 17, 2022 at 12:26 PM H.J. Lu via Gcc-patches
> wrote:
> >
> > Reading YMM registers with all zero bits needs VZEROUPPER on Sandy Bride,
> > Ivy Bridge, Haswell, Broadwell and Alder Lake to avoid SSE <-> AVX
> > tra
On Thu, Feb 17, 2022 at 12:26 PM H.J. Lu via Gcc-patches
wrote:
>
> Reading YMM registers with all zero bits needs VZEROUPPER on Sandy Bride,
> Ivy Bridge, Haswell, Broadwell and Alder Lake to avoid SSE <-> AVX
> transition penalty. Add TARGET_READ_ZERO_YMM_ZMM_NEED_VZEROUPPER to
> generate vzero
Reading YMM registers with all zero bits needs VZEROUPPER on Sandy Bride,
Ivy Bridge, Haswell, Broadwell and Alder Lake to avoid SSE <-> AVX
transition penalty. Add TARGET_READ_ZERO_YMM_ZMM_NEED_VZEROUPPER to
generate vzeroupper instruction after loading all-zero YMM/YMM registers
and enable it by
