[Mesa-dev] [PATCH 08/10] glsl: parser changes for GL_ARB_explicit_uniform_location

[Tapani Pälli]

Patch adds a preprocessor define for the extension and stores explicit
location data for uniforms during AST->HIR conversion. It also sets
layout token to be available when having the extension in place.

Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
---
 src/glsl/ast_to_hir.cpp       | 37 +++++++++++++++++++++++++++++++++++++
 src/glsl/glcpp/glcpp-parse.y  |  3 +++
 src/glsl/glsl_lexer.ll        |  1 +
 src/glsl/glsl_parser_extras.h | 14 ++++++++++++++
 4 files changed, 55 insertions(+)

diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
index 8d55ee3..7431ad7 100644
--- a/src/glsl/ast_to_hir.cpp
+++ b/src/glsl/ast_to_hir.cpp
@@ -2170,6 +2170,43 @@ validate_explicit_location(const struct ast_type_qualifier *qual,
 {
    bool fail = false;
 
+   /* Checks for GL_ARB_explicit_uniform_location. */
+   if (qual->flags.q.uniform) {
+
+      if (!state->check_explicit_uniform_location_allowed(loc, var))
+         return;
+
+      const struct gl_context *const ctx = state->ctx;
+      unsigned max_loc = qual->location + var->type->component_slots() - 1;
+
+      /* ARB_explicit_uniform_location specification states:
+       *
+       *     "The explicitly defined locations and the generated locations
+       *     must be in the range of 0 to MAX_UNIFORM_LOCATIONS minus one."
+       *
+       *     "Valid locations for default-block uniform variable locations
+       *     are in the range of 0 to the implementation-defined maximum
+       *     number of uniform locations."
+       */
+      if (qual->location < 0) {
+         _mesa_glsl_error(loc, state,
+                          "explicit location < 0 for uniform %s", var->name);
+         return;
+      }
+
+      if (max_loc >= ctx->Const.MaxUserAssignableUniformLocations) {
+         _mesa_glsl_error(loc, state, "location qualifier for uniform %s "
+                          ">= MAX_UNIFORM_LOCATIONS (%u)",
+                          var->name,
+                          ctx->Const.MaxUserAssignableUniformLocations);
+         return;
+      }
+
+      var->data.explicit_location = true;
+      var->data.location = qual->location;
+      return;
+   }
+
    /* Between GL_ARB_explicit_attrib_location an
     * GL_ARB_separate_shader_objects, the inputs and outputs of any shader
     * stage can be assigned explicit locations.  The checking here associates
diff --git a/src/glsl/glcpp/glcpp-parse.y b/src/glsl/glcpp/glcpp-parse.y
index f28d853..6d42138 100644
--- a/src/glsl/glcpp/glcpp-parse.y
+++ b/src/glsl/glcpp/glcpp-parse.y
@@ -2087,6 +2087,9 @@ _glcpp_parser_handle_version_declaration(glcpp_parser_t *parser, intmax_t versio
 	      if (extensions->ARB_explicit_attrib_location)
 	         add_builtin_define(parser, "GL_ARB_explicit_attrib_location", 1);
 
+	      if (extensions->ARB_explicit_uniform_location)
+	         add_builtin_define(parser, "GL_ARB_explicit_uniform_location", 1);
+
 	      if (extensions->ARB_shader_texture_lod)
 	         add_builtin_define(parser, "GL_ARB_shader_texture_lod", 1);
 
diff --git a/src/glsl/glsl_lexer.ll b/src/glsl/glsl_lexer.ll
index 7602351..83f0b6d 100644
--- a/src/glsl/glsl_lexer.ll
+++ b/src/glsl/glsl_lexer.ll
@@ -393,6 +393,7 @@ layout		{
 		      || yyextra->AMD_conservative_depth_enable
 		      || yyextra->ARB_conservative_depth_enable
 		      || yyextra->ARB_explicit_attrib_location_enable
+		      || yyextra->ARB_explicit_uniform_location_enable
                       || yyextra->has_separate_shader_objects()
 		      || yyextra->ARB_uniform_buffer_object_enable
 		      || yyextra->ARB_fragment_coord_conventions_enable
diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h
index c53c583..20879a0 100644
--- a/src/glsl/glsl_parser_extras.h
+++ b/src/glsl/glsl_parser_extras.h
@@ -152,6 +152,20 @@ struct _mesa_glsl_parse_state {
       return true;
    }
 
+   bool check_explicit_uniform_location_allowed(YYLTYPE *locp,
+                                                const ir_variable *var)
+   {
+      /* Requires OpenGL 3.3 or ARB_explicit_attrib_location. */
+      if (ctx->Version < 33 && !ctx->Extensions.ARB_explicit_attrib_location) {
+         _mesa_glsl_error(locp, this, "%s explicit location requires "
+                          "GL_ARB_explicit_attrib_location extension "
+                          "or OpenGL 3.3", mode_string(var));
+         return false;
+      }
+
+      return true;
+   }
+
    bool has_explicit_attrib_location() const
    {
       return ARB_explicit_attrib_location_enable || is_version(330, 300);
-- 
1.9.0