PPC64 libmvec implementation of sincos

Richard Biener richard.guenther@gmail.com
Fri Jan 17 16:37:00 GMT 2020


On Thu, Jan 16, 2020 at 4:54 PM GT <tnggil@protonmail.com> wrote:
>
>
> ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
> On Wednesday, January 15, 2020 3:20 PM, GT <tnggil@protonmail.com> wrote:
>
> > ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
> > On Thursday, January 9, 2020 8:42 AM, Richard Biener richard.guenther@gmail.com wrote:
> >
> > > As for the other question for testing you probably want to provide a
> > > OMP simd declaration
> > > of a function like
> > > _Complex double mycexpi (double);
> > > and make a testcase like
> > > void foo (_Complex double * __restrict out, double *in)
> > > {
> > > for (int i = 0; i < 1024; ++i)
> > > {
> > > out[i] = mycexpi (in[i]);
> > > }
> > > }
> > > or eventually with two output arrays and explicit __real/__imag
> > > processing. The real
> > > and main question is how is the OMP SIMD declaration of mycexpi looking like?
> > > So I'd completely side-step sincos() and GCCs sincos() ->
> > > __builtin_cepxi transform
> > > and concentrate on OMP SIMD of a function with the signature we need to handle.
> > > Richard.
> >
> > I think what is required here is to attach either #pragma omp declare simd orattribute ((simd))
> > to the declaration of builtin cexpi. In gcc/builtins.def, some attributes are provided during
> > creation of cexpi (line 656, call containing BUILT_IN_CEXPI). Attaching the simd attributes to
> > function declarations is how sin, cos, and the other math functions were handled in math-vector.h
> > glibc header file.
>
> You probably intended that we first teach GCC how to vectorize any function which returns a
> _Complex double and has a single parameter of type double. When that's done, move on to solving
> the specific vectorization of __builtin_cexpi. Right?

Yes.

Richard.

> Bert.



More information about the Gcc mailing list