On Fri, Aug 22, 2014 at 2:23 PM, Frank Henigman <fjhenig...@google.com> wrote:
> If a precision qualifer is allowed on type T, it should be allowed
> on an array of T. Refactor the check to ensure this is the case.
> ---
> I wanted to expand the comment to say why is_record() is in there,
> but I don't understand why it is. I thought structs couldn't have
> precision qualifiers.
Right. I noticed some error messages in src/glsl/ast_to_hir.cpp
supporting your argument:
"precision qualifiers do not apply to structures"
"precision qualifiers can't be applied to structures"
We have piglit tests for this which currently pass with Mesa master:
tests/spec/glsl-es-1.00/compiler/precision-qualifiers/precision-struct-01.frag
tests/spec/glsl-es-1.00/compiler/precision-qualifiers/precision-struct-02.frag
So, I think we can just omit is_record() entry from here.
>
> src/glsl/ast_to_hir.cpp | 75
> +++++++++++++++++++++++++++----------------------
> 1 file changed, 41 insertions(+), 34 deletions(-)
>
> diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
> index 30b02d0..998404a 100644
> --- a/src/glsl/ast_to_hir.cpp
> +++ b/src/glsl/ast_to_hir.cpp
> @@ -3202,6 +3202,41 @@ validate_identifier(const char *identifier, YYLTYPE
> loc,
> }
> }
>
> +static bool
> +precision_qualifier_allowed(const glsl_type *type)
> +{
> + /* Precision qualifiers apply to floating point, integer and sampler
> + * types.
> + *
> + * Section 4.5.2 (Precision Qualifiers) of the GLSL 1.30 spec says:
> + * "Any floating point or any integer declaration can have the type
> + * preceded by one of these precision qualifiers [...] Literal
> + * constants do not have precision qualifiers. Neither do Boolean
> + * variables.
> + *
> + * Section 4.5 (Precision and Precision Qualifiers) of the GLSL 1.30
> + * spec also says:
> + *
> + * "Precision qualifiers are added for code portability with OpenGL
> + * ES, not for functionality. They have the same syntax as in OpenGL
> + * ES."
> + *
> + * Section 8 (Built-In Functions) of the GLSL ES 1.00 spec says:
> + *
> + * "uniform lowp sampler2D sampler;
> + * highp vec2 coord;
> + * ...
> + * lowp vec4 col = texture2D (sampler, coord);
> + * // texture2D returns lowp"
> + *
> + * From this, we infer that GLSL 1.30 (and later) should allow precision
> + * qualifiers on sampler types just like float and integer types.
> + */
> + return type->is_float()
> + || type->is_integer()
> + || type->is_record()
> + || type->is_sampler();
> +}
>
> ir_rvalue *
> ast_declarator_list::hir(exec_list *instructions,
> @@ -3689,41 +3724,13 @@ ast_declarator_list::hir(exec_list *instructions,
> }
>
>
> - /* Precision qualifiers apply to floating point, integer and sampler
> - * types.
> - *
> - * Section 4.5.2 (Precision Qualifiers) of the GLSL 1.30 spec says:
> - * "Any floating point or any integer declaration can have the type
> - * preceded by one of these precision qualifiers [...] Literal
> - * constants do not have precision qualifiers. Neither do Boolean
> - * variables.
> - *
> - * Section 4.5 (Precision and Precision Qualifiers) of the GLSL 1.30
> - * spec also says:
> - *
> - * "Precision qualifiers are added for code portability with OpenGL
> - * ES, not for functionality. They have the same syntax as in
> OpenGL
> - * ES."
> - *
> - * Section 8 (Built-In Functions) of the GLSL ES 1.00 spec says:
> - *
> - * "uniform lowp sampler2D sampler;
> - * highp vec2 coord;
> - * ...
> - * lowp vec4 col = texture2D (sampler, coord);
> - * // texture2D returns
> lowp"
> - *
> - * From this, we infer that GLSL 1.30 (and later) should allow
> precision
> - * qualifiers on sampler types just like float and integer types.
> + /* If a precision qualifier is allowed on a type, it is allowed on
> + * an array of that type.
> */
> - if (this->type->qualifier.precision != ast_precision_none
> - && !var->type->is_float()
> - && !var->type->is_integer()
> - && !var->type->is_record()
> - && !var->type->is_sampler()
> - && !(var->type->is_array()
> - && (var->type->fields.array->is_float()
> - || var->type->fields.array->is_integer()))) {
> + if (!(this->type->qualifier.precision == ast_precision_none
> + || precision_qualifier_allowed(var->type)
> + || (var->type->is_array()
> + && precision_qualifier_allowed(var->type->fields.array)))) {
>
> _mesa_glsl_error(&loc, state,
> "precision qualifiers apply only to floating point"
> --
> 2.1.0.rc2.206.gedb03e5
>
I think it would be better to omit the is_record() check in a separate
patch.
This patch is: Reviewed-by: Anuj Phogat <anuj.pho...@gmail.com>
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