[Mesa-dev] [PATCH v2 24/25] i965: Call spirv_to_nir() instead of glsl_to_nir() for SPIR-V shaders

[Timothy Arceri]

On 01/12/17 04:28, Eduardo Lima Mitev wrote:
> This is the main fork of the shader compilation code-path, where a NIR
> shader is obtained by calling spirv_to_nir() or glsl_to_nir(),
> depending on its nature..
> 
> v2: Use 'spirv_data' member from gl_linked_shader to know which method
>     to call. (Timothy Arceri)
> ---
>   src/mesa/drivers/dri/i965/brw_program.c | 14 ++++++++++++--
>   1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_program.c b/src/mesa/drivers/dri/i965/brw_program.c
> index 755d4973cc0..596118f2fe5 100644
> --- a/src/mesa/drivers/dri/i965/brw_program.c
> +++ b/src/mesa/drivers/dri/i965/brw_program.c
> @@ -31,6 +31,7 @@
>   
>   #include <pthread.h>
>   #include "main/imports.h"
> +#include "main/glspirv.h"
>   #include "program/prog_parameter.h"
>   #include "program/prog_print.h"
>   #include "program/prog_to_nir.h"
> @@ -73,9 +74,18 @@ brw_create_nir(struct brw_context *brw,
>         ctx->Const.ShaderCompilerOptions[stage].NirOptions;
>      nir_shader *nir;
>   
> -   /* First, lower the GLSL IR or Mesa IR to NIR */
> +   /* First, lower the GLSL/Mesa IR or SPIR-V to NIR */
>      if (shader_prog) {
> -      nir = glsl_to_nir(shader_prog, stage, options);
> +      bool is_spirv_shader =
> +         (shader_prog->_LinkedShaders[stage]->spirv_data != NULL);
> +
> +      if (!is_spirv_shader) {
> +         nir = glsl_to_nir(shader_prog, stage, options);
> +      } else {
> +         nir = _mesa_spirv_to_nir(ctx, shader_prog, stage, options);
> +      }
> +      assert (nir);

Rather than messing around with bools, null checks and !'s I'd just 
change this to:

       /* First, lower the GLSL/Mesa IR or SPIR-V to NIR */
       if (shader_prog->_LinkedShaders[stage]->spirv_data) {
          nir = _mesa_spirv_to_nir(ctx, shader_prog, stage, options);
       } else {
          nir = glsl_to_nir(shader_prog, stage, options);
       }
       assert (nir);


> +
>         nir_remove_dead_variables(nir, nir_var_shader_in | nir_var_shader_out);
>         nir_lower_returns(nir);
>         nir_validate_shader(nir);
>