On Wed, Aug 19, 2020 at 3:52 AM Hongtao Liu <crazy...@gmail.com> wrote:
>
> On Mon, Aug 17, 2020 at 5:20 PM Uros Bizjak <ubiz...@gmail.com> wrote:
> >
> > On Fri, Aug 14, 2020 at 10:22 AM Hongtao Liu <crazy...@gmail.com> wrote:
> > >
> > > Hi:
> > > First, since avx512 masks involve both vector isa and general part,
> > > so i add both maintainers to the maillist.
> > >
> > > I'm doing this in 4 steps:
> > > 1 - Add cost model for operation of mask registers.
> > > 2 - Introduce new cover class INT_MASK_REGS, this will enable direct
> > > move between gpr and mask registers in pass_reload by consideration of
> > > cost model, this is similar as INT_SSE_REGS.
> > > 3 - Tune cost model.
> > > 4 - Enable operator or/xor/and/andn/not for mask register. kxnor is
> > > not enabled since there's no corresponding instruction for general
> > > registers, 64bit mask op is not enabled for 32bit target.
> > > kadd/kshift/ktest are not merged into general versionsadd/ashl/test
> > > since i think it would be odd to use mask register for those
> > > operations.
> > >
> > > Bootstrap is ok, regression test is ok for i386/x86-64 result.
> > > There's some improvement for performance of SPEC2017 tested on SKL,
> > > i observe there're many spills from integer to mask registers instead
> > > of memory which is the reason for the improvement.
> >
> > + if (MASK_CLASS_P (regclass))
> > + {
> > + int index;
> > + switch (GET_MODE_SIZE (mode))
> > + {
> > + case 1:
> > + index = 0;
> > + break;
> > + case 2:
> > + index = 1;
> > + break;
> > + default:
> > + index = 3;
> >
> > Max index = 2!
> >
>
> Fix typo.
>
> > + break;
> > + }
> > +
> > + if (in == 2)
> > + return MAX (ix86_cost->hard_register.mask_load[index],
> > + ix86_cost->hard_register.mask_store[index]);
> > + return in ? ix86_cost->hard_register.mask_load[2]
> > + : ix86_cost->hard_register.mask_store[2];
> > + }
> >
> > Are DImode loads and stores assumed to cost the same as SImode? A
> > comment would be nice here.
> >
>
> Yes, comment is added.
>
> > Uros.
>
> Update patch.
Patch is OK (no comment on costs, though).
Thanks,
Uros.
