On Fri, Mar 29, 2019 at 10:50:04PM +1030, Alan Modra wrote:
> On Fri, Mar 29, 2019 at 04:47:21AM -0500, Segher Boessenkool wrote:
> > On Fri, Mar 29, 2019 at 04:00:55PM +1030, Alan Modra wrote:
> > > On Thu, Mar 28, 2019 at 01:08:55PM -0500, Segher Boessenkool wrote:
> > > > TARGET_DIRECT_MOVE is always on for these CPUs. Should this also use
> > > > the
> > > > m*vsr* cost with say -mcpu=power7 -mtune=power9?
> > >
> > > No, because if we don't generate m*vsr*, and we shouldn't, then that
> > > would be telling a lie.
> >
> > Then should we have those "tune" things in this conditional? Just do it
> > for any direct move target?
>
> Oh, right. I think we still need to "tune" the cost to reflect
> actual hardware, but that shouldn't be in the outer condition. So
>
> if (TARGET_DIRECT_MOVE)
> {
> if (rs6000_tune != PROCESSOR_POWER9)
> ret = 4 * hard_regno_nregs (0, mode);
> else
> ret = 2 * hard_regno_nregs (0, mode);
> ...
>
> should be good enough.
Yes exactly.
Segher
