[PATCH] Use generic vector computations in s_sincosf.h

[H.J. Lu]

On Mon, Dec 3, 2018 at 12:22 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Mon, Dec 3, 2018 at 10:44 AM Wilco Dijkstra <Wilco.Dijkstra@arm.com> wrote:
> >
> > Hi,
> >
> > > H.J. Lu wrote:
> > > Only sincosf_poly is vectorized.  Without changing the existing
> > > structure, I need
> > > to duplicate everything in sysdeps/ieee754/flt-32/s_sincosf.h.
> >
> > The only shared function which relies on the structure is reduce_fast.
> > To avoid any duplication it could just get the 2 values it needs as arguments.
> >
> > > My x86-64 vector version has x86-64 specific intrinsics:
> > >
> > >  __v2df vps1c2 = (__v2df) _mm_loadu_pd (&p->s1c2.s1);
> > >  __v2df vps2c3 = (__v2df) _mm_loadu_pd (&p->s2c3.s2);
> > >  __v2df vps3c4 = (__v2df) _mm_loadu_pd (&p->s3c4.s3);
> >
> > Simple vector loads are supported, you don't need any intrinsics for these.
>
> I try to replace
>
>   struct
>     {
>       double s1;
>       double c2;
>     } s1c2;
>
> with __v2df.
>
> > >  __v4sf v4sf = _mm_cvtpd_ps (vsincos);
> >
> > This works fine too for me using v4sf = {(float)vsincos[0], (float)vsincos[1]};
> >
>
> I got
>
>         vcvtsd2ss       %xmm1, %xmm2, %xmm0
>         vunpckhpd       %xmm1, %xmm1, %xmm1
>         vmovss  %xmm0, (%rdi)
>         vcvtsd2ss       %xmm1, %xmm2, %xmm2
>         vmovss  %xmm2, (%rsi)
>         ret
>
> instead of
>
>         vcvtpd2psx      %xmm2, %xmm2
>         vmovss  %xmm2, (%rdi)
>         vextractps      $1, %xmm2, (%rsi)
>         ret
>
> I prefer
>
>  __v4sf v4sf = _mm_cvtpd_ps (vsincos);
>

I am testing this patch to use generic vector computations in s_sincosf.h.
OK for master if build-many-glibcs.py passes?

-- 
H.J.
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