[Mesa-dev] [PATCH 3/5] main/version: Don't require ARB_compute_shader for OpenGLES 3.1

[Ian Romanick]

On 12/15/2015 04:08 PM, Jordan Justen wrote:
> The OpenGL ARB_compute_shader extension specfication requires at least
> 1024 for GL_MAX_COMPUTE_WORK_GROUP_INVOCATIONS, whereas OpenGLES 3.1
> only required 128.

Does this mean that extensions->ARB_compute_shader is not set?  I'm a
little bit nervous about that.  Are we sure that we check for compute
shader support correctly everywhere (i.e., don't just check the
extension bit that isn't set)?

> Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
> Cc: Ian Romanick <idr at freedesktop.org>
> Cc: Marta Lofstedt <marta.lofstedt at intel.com>
> ---
>  src/mesa/main/version.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/src/mesa/main/version.c b/src/mesa/main/version.c
> index e92bb11..112a73d 100644
> --- a/src/mesa/main/version.c
> +++ b/src/mesa/main/version.c
> @@ -433,7 +433,8 @@ compute_version_es1(const struct gl_extensions *extensions)
>  }
>  
>  static GLuint
> -compute_version_es2(const struct gl_extensions *extensions)
> +compute_version_es2(const struct gl_extensions *extensions,
> +                    const struct gl_constants *consts)
>  {
>     /* OpenGL ES 2.0 is derived from OpenGL 2.0 */
>     const bool ver_2_0 = (extensions->ARB_texture_cube_map &&
> @@ -464,9 +465,11 @@ compute_version_es2(const struct gl_extensions *extensions)
>                           extensions->EXT_texture_snorm &&
>                           extensions->NV_primitive_restart &&
>                           extensions->OES_depth_texture_cube_map);
> +   const bool es31_compute_shader =
> +      consts->MaxComputeWorkGroupInvocations >= 128;
>     const bool ver_3_1 = (ver_3_0 &&
>                           extensions->ARB_arrays_of_arrays &&
> -                         extensions->ARB_compute_shader &&
> +                         es31_compute_shader &&
>                           extensions->ARB_draw_indirect &&
>                           extensions->ARB_explicit_uniform_location &&
>                           extensions->ARB_framebuffer_no_attachments &&
> @@ -508,7 +511,7 @@ _mesa_get_version(const struct gl_extensions *extensions,
>     case API_OPENGLES:
>        return compute_version_es1(extensions);
>     case API_OPENGLES2:
> -      return compute_version_es2(extensions);
> +      return compute_version_es2(extensions, consts);
>     }
>     return 0;
>  }
>