[Mesa-dev] [PATCH 1/5] glsl: Restrict functions to not return arrays or SOAs in GLSL 1.00.

[Samuel Pitoiset]

On 05/02/2017 07:36 PM, Eric Anholt wrote:
>  From the spec,
> 
>      Arrays are allowed as arguments, but not as the return type. [...] The
>      return type can also be a structure if the structure does not contain
>      an array.
> 
> Fixes DEQP shaders.functions.invalid.return_array_in_struct_fragment.
> ---
>   src/compiler/glsl/ast_to_hir.cpp | 12 ++++++++++++
>   src/compiler/glsl_types.cpp      | 13 +++++++++++++
>   src/compiler/glsl_types.h        |  6 ++++++
>   3 files changed, 31 insertions(+)
> 
> diff --git a/src/compiler/glsl/ast_to_hir.cpp b/src/compiler/glsl/ast_to_hir.cpp
> index 1159b2cdfbf9..9e02529dffb9 100644
> --- a/src/compiler/glsl/ast_to_hir.cpp
> +++ b/src/compiler/glsl/ast_to_hir.cpp
> @@ -5608,6 +5608,18 @@ ast_function::hir(exec_list *instructions,
>                          "sized", name);
>      }
>   
> +   /* Section 6.1 (Function Definitions) of the GLSL 1.00 spec says:

Looks like we usually format like:

/* From section 6.1 (Function Definitions) of the GLSL 1.00 spec:

> +    *
> +    *     "Arrays are allowed as arguments, but not as the return type. [...]
> +    *      The return type can also be a structure if the structure does not
> +    *      contain an array."
> +    */
> +   if (state->language_version == 100 && return_type->contains_array()) {
> +      YYLTYPE loc = this->get_location();
> +      _mesa_glsl_error(& loc, state,
> +                       "function `%s' return type contains an array", name);
> +   }
> +
>      /* From section 4.1.7 of the GLSL 4.40 spec:
>       *
>       *    "[Opaque types] can only be declared as function parameters
> diff --git a/src/compiler/glsl_types.cpp b/src/compiler/glsl_types.cpp
> index 0480bef80eca..a52625ad7b52 100644
> --- a/src/compiler/glsl_types.cpp
> +++ b/src/compiler/glsl_types.cpp
> @@ -225,6 +225,19 @@ glsl_type::contains_sampler() const
>      }
>   }
>   
> +bool
> +glsl_type::contains_array() const
> +{
> +   if (this->is_record() || this->is_interface()) {
> +      for (unsigned int i = 0; i < this->length; i++) {
> +         if (this->fields.structure[i].type->contains_array())
> +            return true;
> +      }
> +      return false;
> +   } else {
> +      return this->is_array();
> +   }
> +}
>   
>   bool
>   glsl_type::contains_integer() const
> diff --git a/src/compiler/glsl_types.h b/src/compiler/glsl_types.h
> index 403663f7b87a..6b2de11117c2 100644
> --- a/src/compiler/glsl_types.h
> +++ b/src/compiler/glsl_types.h
> @@ -561,6 +561,12 @@ struct glsl_type {
>      bool contains_sampler() const;
>   
>      /**
> +    * Query whether or not type is an array or for struct, interface and
> +    * array types, contains an array.
> +    */
> +   bool contains_array() const;
> +
> +   /**
>       * Get the Mesa texture target index for a sampler type.
>       */
>      gl_texture_index sampler_index() const;
>