[Mesa-dev] [PATCH v2 12/24] mesa: refactor GetAttribLocation

[Martin Peres]

On 01/04/15 15:14, Tapani Pälli wrote:
> Use program_resource_location to fetch location.
>
> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
> ---
>   src/mesa/main/shader_query.cpp | 42 ++++++++++++++++++++----------------------
>   1 file changed, 20 insertions(+), 22 deletions(-)
>
> diff --git a/src/mesa/main/shader_query.cpp b/src/mesa/main/shader_query.cpp
> index 0f7804c..cbdcc61 100644
> --- a/src/mesa/main/shader_query.cpp
> +++ b/src/mesa/main/shader_query.cpp
> @@ -41,6 +41,10 @@ extern "C" {
>   #include "shaderapi.h"
>   }
>   
> +static GLint
> +program_resource_location(struct gl_shader_program *shProg,
> +                          struct gl_program_resource *res, const char *name);
> +
>   /**
>    * Declare convenience functions to return resource data in a given type.
>    * Warning! this is not type safe so be *very* careful when using these.
> @@ -266,31 +270,25 @@ _mesa_GetAttribLocation(GLhandleARB program, const GLcharARB * name)
>      if (shProg->_LinkedShaders[MESA_SHADER_VERTEX] == NULL)
>         return -1;
>   
> -   exec_list *ir = shProg->_LinkedShaders[MESA_SHADER_VERTEX]->ir;
> -   foreach_in_list(ir_instruction, node, ir) {
> -      const ir_variable *const var = node->as_variable();
> -
> -      /* The extra check against VERT_ATTRIB_GENERIC0 is because
> -       * glGetAttribLocation cannot be used on "conventional" attributes.
> -       *
> -       * From page 95 of the OpenGL 3.0 spec:
> -       *
> -       *     "If name is not an active attribute, if name is a conventional
> -       *     attribute, or if an error occurs, -1 will be returned."
> -       */
> -      if (var == NULL
> -	  || var->data.mode != ir_var_shader_in
> -	  || var->data.location == -1
> -	  || var->data.location < VERT_ATTRIB_GENERIC0)
> -	 continue;
> +   struct gl_program_resource *res =
> +      _mesa_program_resource_find_name(shProg, GL_PROGRAM_INPUT, name);
>   
> -      int index = get_matching_index(var, (const char *) name);
> +   if (!res)
> +      return -1;
>   
> -      if (index >= 0)
> -         return var->data.location + index - VERT_ATTRIB_GENERIC0;
> -   }
> +   GLint loc = program_resource_location(shProg, res, name);
>   
> -   return -1;
> +   /* The extra check against against 0 is made because of builtin-attribute
> +    * locations that have offset applied. Function program_resource_location
> +    * can return built-in attribute locations < 0 and glGetAttribLocation
> +    * cannot be used on "conventional" attributes.
> +    *
> +    * From page 95 of the OpenGL 3.0 spec:
> +    *
> +    *     "If name is not an active attribute, if name is a conventional
> +    *     attribute, or if an error occurs, -1 will be returned."
> +    */
> +   return (loc >= 0) ? loc : -1;
>   }

Great code-deduplication.

Reviewed-by: Martin Peres <martin.peres at linux.intel.com>