PPC64 libmvec implementation of sincos

[GT]

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Monday, December 9, 2019 3:39 AM, Richard Biener <richard.guenther@gmail.com> wrote:

> > I'm modifying the code trying to get complex double accepted as a valid type by the vectorizer.
> > This is the first time I'm dealing with GCC source so I ask for some patience.
> > Function mode_for_vector in gcc/stor-layout.c requires a new else-if for complex double. I cannot
> > seem to find a header file where MIN_MODE_VECTOR_FLOAT and similar macros are defined. I expect
> > a new MIN_MODE_COMPLEX_VECTOR_FLOAT to be defined in the same file as the existing similar macros.
> > How do I go about making this change?
>
> You don't want to do it this way but map _Complex double to a vector
> of 2 * n doubles instead.
> Look into get_related_vectype_for_scalar_type where it alreday has
> code to "change" the
> scalar type into something that fits what we allow for vectors.
>

I need more guidance on how to proceed here. Function mode_for_vector is called by
build_vector_type_for_mode. The latter is called by get_related_vectype_for_scalar_type,
which you suggested to study for a preferred implementation. The code in mode_for_vector
relies on the relationship that vector mode E_V2DFmode is composed of E_DFmode scalars.
The complex argument has mode E_DCmode. Where should I create a relationship between
E_V2DFmode and E_DCmode so that mode_for_vector returns the appropriate vector mode?
The solution has to be general so that single precision float complex vectorization is
also supported.

Bert.