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.

-- 
Alan Modra
Australia Development Lab, IBM

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