[Mesa-dev] [PATCH v2 8/8] glsl/linker: validate explicit locations for SSO programs

[Ilia Mirkin]

For all the patches in the series that I didn't have comments on,

Reviewed-by: Ilia Mirkin <imirkin at alum.mit.edu>

On Tue, Oct 24, 2017 at 5:28 AM, Iago Toral Quiroga <itoral at igalia.com> wrote:
> v2:
> - we only need to validate inputs to the first stage and outputs
>   from the last stage, everything else has already been validated
>   during cross_validate_outputs_to_inputs (Timothy).
> - Use MAX_VARYING instead of MAX_VARYINGS_INCL_PATCH (Illia)
> ---
>  src/compiler/glsl/link_varyings.cpp | 55 +++++++++++++++++++++++++++++++++++++
>  src/compiler/glsl/link_varyings.h   |  6 ++++
>  src/compiler/glsl/linker.cpp        | 10 +++++++
>  3 files changed, 71 insertions(+)
>
> diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp
> index 02a48f7199..e80736fb38 100644
> --- a/src/compiler/glsl/link_varyings.cpp
> +++ b/src/compiler/glsl/link_varyings.cpp
> @@ -600,6 +600,61 @@ validate_explicit_variable_location(struct gl_context *ctx,
>  }
>
>  /**
> + * Validate explicit locations for the inputs to the first stage and the
> + * outputs of the last stage in an SSO program (everything in between is
> + * validated in cross_validate_outputs_to_inputs).
> + */
> +void
> +validate_sso_explicit_locations(struct gl_context *ctx,
> +                                struct gl_shader_program *prog,
> +                                gl_shader_stage first_stage,
> +                                gl_shader_stage last_stage)
> +{
> +   assert(prog->SeparateShader);
> +
> +   /* VS inputs and FS outputs are validated in
> +    * assign_attribute_or_color_locations()
> +    */
> +   bool validate_first_stage = first_stage != MESA_SHADER_VERTEX;
> +   bool validate_last_stage = last_stage != MESA_SHADER_FRAGMENT;
> +   if (!validate_first_stage && !validate_last_stage)
> +      return;
> +
> +   struct explicit_location_info explicit_locations[MAX_VARYING][4];
> +
> +   gl_shader_stage stages[2] = { first_stage, last_stage };
> +   bool validate_stage[2] = { validate_first_stage, validate_last_stage };
> +   ir_variable_mode var_direction[2] = { ir_var_shader_in, ir_var_shader_out };
> +
> +   for (unsigned i = 0; i < 2; i++) {
> +      if (!validate_stage[i])
> +         continue;
> +
> +      gl_shader_stage stage = stages[i];
> +
> +      gl_linked_shader *sh = prog->_LinkedShaders[stage];
> +      assert(sh);
> +
> +      memset(explicit_locations, 0, sizeof(explicit_locations));
> +
> +      foreach_in_list(ir_instruction, node, sh->ir) {
> +         ir_variable *const var = node->as_variable();
> +
> +         if (var == NULL ||
> +             !var->data.explicit_location ||
> +             var->data.location < VARYING_SLOT_VAR0 ||
> +             var->data.mode != var_direction[i])
> +            continue;
> +
> +         if (!validate_explicit_variable_location(
> +               ctx, explicit_locations, var, prog, sh)) {
> +            return;
> +         }
> +      }
> +   }
> +}
> +
> +/**
>   * Validate that outputs from one stage match inputs of another
>   */
>  void
> diff --git a/src/compiler/glsl/link_varyings.h b/src/compiler/glsl/link_varyings.h
> index 081b04ea38..e052a2b3e5 100644
> --- a/src/compiler/glsl/link_varyings.h
> +++ b/src/compiler/glsl/link_varyings.h
> @@ -300,6 +300,12 @@ link_varyings(struct gl_shader_program *prog, unsigned first, unsigned last,
>                struct gl_context *ctx, void *mem_ctx);
>
>  void
> +validate_sso_explicit_locations(struct gl_context *ctx,
> +                                struct gl_shader_program *prog,
> +                                gl_shader_stage first,
> +                                gl_shader_stage last);
> +
> +void
>  cross_validate_outputs_to_inputs(struct gl_context *ctx,
>                                   struct gl_shader_program *prog,
>                                   gl_linked_shader *producer,
> diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
> index 3798309678..8c610df9bf 100644
> --- a/src/compiler/glsl/linker.cpp
> +++ b/src/compiler/glsl/linker.cpp
> @@ -4938,6 +4938,16 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
>        prev = i;
>     }
>
> +   /* The cross validation of outputs/inputs above validates explicit locations
> +    * but for SSO programs we need to do this also for the inputs in the
> +    * first stage and outputs of the last stage included in the program, since
> +    * there is no cross validation for these.
> +    */
> +   if (prog->SeparateShader)
> +      validate_sso_explicit_locations(ctx, prog,
> +                                      (gl_shader_stage) first,
> +                                      (gl_shader_stage) last);
> +
>     /* Cross-validate uniform blocks between shader stages */
>     validate_interstage_uniform_blocks(prog, prog->_LinkedShaders);
>     if (!prog->data->LinkStatus)
> --
> 2.11.0
>