[Mesa-dev] [PATCH 06/10] glsl: invariant qualifier is not valid for shader inputs in GLSL ES 3.00

[Eduardo Lima Mitev]

From: Samuel Iglesias Gonsalvez <siglesias at igalia.com>

GLSL ES 3.00 spec, chapter 4.6.1 "The Invariant Qualifier",

    Only variables output from a shader can be candidates for invariance. This
    includes user-defined output variables and the built-in output variables.
    As only outputs can be declared as invariant, an invariant output from one
    shader stage will still match an input of a subsequent stage without the
    input being declared as invariant.

This patch fixes the following dEQP tests:

dEQP-GLES3.functional.shaders.qualification_order.variables.valid.invariant_interp_storage_precision
dEQP-GLES3.functional.shaders.qualification_order.variables.valid.invariant_interp_storage
dEQP-GLES3.functional.shaders.qualification_order.variables.valid.invariant_storage_precision
dEQP-GLES3.functional.shaders.qualification_order.variables.valid.invariant_storage
dEQP-GLES3.functional.shaders.qualification_order.variables.invalid.invariant_interp_storage_precision_invariant_input
dEQP-GLES3.functional.shaders.qualification_order.variables.invalid.invariant_interp_storage_invariant_input
dEQP-GLES3.functional.shaders.qualification_order.variables.invalid.invariant_storage_precision_invariant_input
dEQP-GLES3.functional.shaders.qualification_order.variables.invalid.invariant_storage_invariant_input

No piglit regressions observed.

Signed-off-by: Samuel Iglesias Gonsalvez <siglesias at igalia.com>
---
 src/glsl/glsl_parser.yy    | 2 ++
 src/glsl/link_varyings.cpp | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/glsl/glsl_parser.yy b/src/glsl/glsl_parser.yy
index 6160e26..55b3a7d 100644
--- a/src/glsl/glsl_parser.yy
+++ b/src/glsl/glsl_parser.yy
@@ -1591,6 +1591,8 @@ type_qualifier:
 
       $$ = $2;
       $$.flags.q.invariant = 1;
+      if (state->es_shader && state->language_version >= 300 && $$.flags.q.in)
+         _mesa_glsl_error(&@1, state, "invariant qualifiers cannot be used with shader inputs");
    }
    | interpolation_qualifier type_qualifier
    {
diff --git a/src/glsl/link_varyings.cpp b/src/glsl/link_varyings.cpp
index 1866ab2..1fe198a 100644
--- a/src/glsl/link_varyings.cpp
+++ b/src/glsl/link_varyings.cpp
@@ -116,7 +116,7 @@ cross_validate_types_and_qualifiers(struct gl_shader_program *prog,
       return;
    }
 
-   if (input->data.invariant != output->data.invariant) {
+   if (!prog->IsES && input->data.invariant != output->data.invariant) {
       linker_error(prog,
                    "%s shader output `%s' %s invariant qualifier, "
                    "but %s shader input %s invariant qualifier\n",
-- 
2.1.3