[Mesa-dev] [PATCH 1/2] st/mesa: simplify shader limit initialization code

[Marek Olšák]

On Thu, Jan 9, 2014 at 8:21 PM, Brian Paul <brianp at vmware.com> wrote:
> Make use of the new gl_constants::Program[] array.
> ---
>  src/mesa/state_tracker/st_extensions.c     |   31 ++++++++--------------------
>  src/mesa/state_tracker/st_glsl_to_tgsi.cpp |   20 +-----------------
>  src/mesa/state_tracker/st_program.h        |   18 ++++++++++++++++
>  3 files changed, 28 insertions(+), 41 deletions(-)
>
> diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
> index c17601a..cc63b36 100644
> --- a/src/mesa/state_tracker/st_extensions.c
> +++ b/src/mesa/state_tracker/st_extensions.c
> @@ -38,6 +38,8 @@
>  #include "st_context.h"
>  #include "st_extensions.h"
>  #include "st_format.h"
> +#include "st_program.h"
> +
>
>  static unsigned _min(unsigned a, unsigned b)
>  {
> @@ -68,8 +70,8 @@ void st_init_limits(struct st_context *st)
>  {
>     struct pipe_screen *screen = st->pipe->screen;
>     struct gl_constants *c = &st->ctx->Const;
> -   unsigned sh;
>     boolean can_ubo = TRUE;
> +   int i;
>
>     c->MaxTextureLevels
>        = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_2D_LEVELS),
> @@ -149,27 +151,12 @@ void st_init_limits(struct st_context *st)
>        can_ubo = FALSE;
>     }
>
> -   for (sh = 0; sh < PIPE_SHADER_TYPES; ++sh) {
> -      struct gl_shader_compiler_options *options;
> -      struct gl_program_constants *pc;
> -
> -      switch (sh) {
> -      case PIPE_SHADER_FRAGMENT:
> -         pc = &c->Program[MESA_SHADER_FRAGMENT];
> -         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_FRAGMENT];
> -         break;
> -      case PIPE_SHADER_VERTEX:
> -         pc = &c->Program[MESA_SHADER_VERTEX];
> -         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_VERTEX];
> -         break;
> -      case PIPE_SHADER_GEOMETRY:
> -         pc = &c->Program[MESA_SHADER_GEOMETRY];
> -         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_GEOMETRY];
> -         break;
> -      default:
> -         /* compute shader, etc. */
> -         continue;
> -      }
> +   /* Note: we only loop over the currently supported gallium shader types */
> +   for (i = MESA_SHADER_VERTEX; i <= MESA_SHADER_FRAGMENT; i++) {

The MESA_SHADER_xxx numbers are ordered in the same way they appear in
the pipeline, so tessellation shaders will be before
MESA_SHADER_FRAGMENT. In other words, the comment in the code is not
true and st_shader_stage_to_ptarget should be more robust to handle
unsupported shader types.

Marek