[Mesa-dev] [PATCH 3/3] glsl/linker: validate explicit locations for SSO programs

[Iago Toral]

On Fri, 2017-10-20 at 22:03 +1100, Timothy Arceri wrote:
> 
> On 20/10/17 21:46, Iago Toral Quiroga wrote:
> > ---
> >   src/compiler/glsl/link_varyings.cpp | 53
> > +++++++++++++++++++++++++++++++++++++
> >   src/compiler/glsl/link_varyings.h   |  4 +++
> >   src/compiler/glsl/linker.cpp        |  6 +++++
> >   3 files changed, 63 insertions(+)
> > 
> > diff --git a/src/compiler/glsl/link_varyings.cpp
> > b/src/compiler/glsl/link_varyings.cpp
> > index dffb4f98df..d7e407184d 100644
> > --- a/src/compiler/glsl/link_varyings.cpp
> > +++ b/src/compiler/glsl/link_varyings.cpp
> > @@ -599,6 +599,59 @@ validate_explicit_variable_location(struct
> > gl_context *ctx,
> >   }
> >   
> >   /**
> > + * Validate explicit locations for SSO programs. For non-SSO
> > programs this
> > + * is alreadty done in cross_validate_outputs_to_inputs().
> > + */
> > +void
> > +validate_sso_explicit_locations(struct gl_context *ctx,
> > +                                struct gl_shader_program *prog)
> > +{
> > +   assert(prog->SeparateShader);
> > +   struct explicit_location_info
> > explicit_locations_in[MAX_VARYINGS_INCL_PATCH][4];
> > +   struct explicit_location_info
> > explicit_locations_out[MAX_VARYINGS_INCL_PATCH][4];
> > +
> > +   for (unsigned i = 0; i <= MESA_SHADER_FRAGMENT; i++) {
> > +      if (prog->_LinkedShaders[i] == NULL)
> > +         continue;
> > +
> > +      gl_linked_shader *sh = prog->_LinkedShaders[i];
> > +
> > +      memset(explicit_locations_in, 0,
> > sizeof(explicit_locations_in));
> > +      memset(explicit_locations_out, 0,
> > sizeof(explicit_locations_out));
> > +
> > +      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 != ir_var_shader_in &&
> > +              var->data.mode != ir_var_shader_out))
> > +            continue;
> > +
> > +         /* Vertex shader inputs and fragment shader outputs are
> > validated
> > +          * in assign_attribute_or_color_locations, skip them.
> > +          */
> > +         if (sh->Stage == MESA_SHADER_FRAGMENT &&
> > +             var->data.mode == ir_var_shader_out)
> > +            continue;
> > +
> > +         if (sh->Stage == MESA_SHADER_VERTEX &&
> > +             var->data.mode == ir_var_shader_in)
> > +            continue;
> > +
> > +         if (!validate_explicit_variable_location(
> > +               ctx,
> > +               var->data.mode == ir_var_shader_in ?
> > explicit_locations_in :
> > +                                                    explicit_locat
> > ions_out,
> > +               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..e8486208a2 100644
> > --- a/src/compiler/glsl/link_varyings.h
> > +++ b/src/compiler/glsl/link_varyings.h
> > @@ -300,6 +300,10 @@ 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);
> > +
> > +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..cba14f940b 100644
> > --- a/src/compiler/glsl/linker.cpp
> > +++ b/src/compiler/glsl/linker.cpp
> > @@ -4938,6 +4938,12 @@ link_shaders(struct gl_context *ctx, struct
> > gl_shader_program *prog)
> >         prev = i;
> >      }
> >   
> > +   /* Validate location aliasing for SSO programs (this is done
> > during
> > +    * cross_validate_outputs_to_inputs for non-SSO programs).
> > +    */
> > +   if (prog->SeparateShader)
> > +      validate_sso_explicit_locations(ctx, prog);
> 
> Somewhere in link shaders we already calculate the first and last
> shader 
> stages. I think we should probably pass those to this function and
> then 
> only run the validation on the input of the first and output of the 
> last, otherwise we are re-validating things the are already covered
> by 
> the non-sso checks.

Aha, good point, thanks. I'll look into that.

Iago

> > +
> >      /* Cross-validate uniform blocks between shader stages */
> >      validate_interstage_uniform_blocks(prog, prog-
> > >_LinkedShaders);
> >      if (!prog->data->LinkStatus)
> > 
> 
>