On 9/4/24 12:55, Jan Hubicka wrote:
On 9/3/24 15:07, Jan Hubicka wrote:
Hi,
We disable gathers for zen4. It seems that gather has improved a bit compared
to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions when
the indices are known ahead of time. Vector loads followed by
On Wed, Sep 4, 2024 at 12:56 PM Jan Hubicka wrote:
>
> > On 9/3/24 15:07, Jan Hubicka wrote:
> >
> > > Hi,
> > > We disable gathers for zen4. It seems that gather has improved a bit
> > > compared
> > > to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions
> > > when
> > > th
> On 9/3/24 15:07, Jan Hubicka wrote:
>
> > Hi,
> > We disable gathers for zen4. It seems that gather has improved a bit
> > compared
> > to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions
> > when
> > the indices are known ahead of time. Vector loads followed by shuffles
On 9/3/24 15:07, Jan Hubicka wrote:
Hi,
We disable gathers for zen4. It seems that gather has improved a bit compared
to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions when
the indices are known ahead of time. Vector loads followed by shuffles result
in a higher load band
On Tue, Sep 3, 2024 at 3:07 PM Jan Hubicka wrote:
>
> Hi,
> We disable gathers for zen4. It seems that gather has improved a bit compared
> to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions when
> the indices are known ahead of time. Vector loads followed by shuffles result
Hi,
We disable gathers for zen4. It seems that gather has improved a bit compared
to zen4 and Zen5 optimization manual suggests "Avoid GATHER instructions when
the indices are known ahead of time. Vector loads followed by shuffles result
in a higher load bandwidth." however the situation seems to
