+
+ir_rvalue *
+ast_uniform_block::hir(exec_list *instructions,
+ struct _mesa_glsl_parse_state *state)
+{
+ YYLTYPE loc = this->get_location();
+
+ /* The ast_uniform_block has a list of ast_declarator_lists. We
+ * need to turn those into ir_variables with an association
+ * with this uniform block.
+ */
+ enum glsl_interface_packing packing;
+ if (this->layout.flags.q.shared) {
+ packing = GLSL_INTERFACE_PACKING_SHARED;
+ } else if (this->layout.flags.q.packed) {
+ packing = GLSL_INTERFACE_PACKING_PACKED;
+ } else {
+ /* The default layout is std140.
+ */
+ packing = GLSL_INTERFACE_PACKING_STD140;
+ }
+
+ bool block_row_major = this->layout.flags.q.row_major;
+ exec_list declared_variables;
+ glsl_struct_field *fields;
+ unsigned int num_variables =
+ ast_process_structure_or_interface_block(&declared_variables,
+ state,
+ &this->declarations,
+ loc,
+ &fields,
+ true,
+ block_row_major);
+
+ const glsl_type *block_type =
+ glsl_type::get_interface_instance(fields,
+ num_variables,
+ packing,
+ this->block_name);
+
+ if (!state->symbols->add_type(block_type->name, block_type)) {
+ YYLTYPE loc = this->get_location();
+ _mesa_glsl_error(&loc, state, "Uniform block name `%s' already taken in "
+ "the current scope.\n", this->block_name);
+ }
+
+ /* Since interface blocks cannot contain statements, it should be
+ * impossible for the block to generate any instructions.
+ */
+ assert(declared_variables.is_empty());
+
+ /* Page 39 (page 45 of the PDF) of section 4.3.7 in the GLSL ES 3.00 spec
+ * says:
+ *
+ * "If an instance name (instance-name) is used, then it puts all the
+ * members inside a scope within its own name space, accessed with the
+ * field selector ( . ) operator (analogously to structures)."
+ */
+ if (this->instance_name) {
+ ir_variable *var;
+
+ if (this->array_size != NULL) {
+ const glsl_type *block_array_type =
+ process_array_type(&loc, block_type, this->array_size, state);
+
+ var = new(state) ir_variable(block_array_type,
+ this->instance_name,
+ ir_var_uniform);
+ } else {
+ var = new(state) ir_variable(block_type,
+ this->instance_name,
+ ir_var_uniform);
+ }
+
+ var->interface_type = block_type;
+ state->symbols->add_variable(var);
+ instructions->push_tail(var);
+ } else {
+ /* In order to have an array size, the block must also be declared with
+ * an instane name.
+ */
+ assert(this->array_size == NULL);
+
+ for (unsigned i = 0; i < num_variables; i++) {
+ ir_variable *var =
+ new(state) ir_variable(fields[i].type,
+ ralloc_strdup(state, fields[i].name),
+ ir_var_uniform);
+ var->interface_type = block_type;
+
+ state->symbols->add_variable(var);
+ instructions->push_tail(var);
+ }
+ }
+
+ return NULL;
+}
+
+static void
+detect_conflicting_assignments(struct _mesa_glsl_parse_state *state,
+ exec_list *instructions)
+{
+ bool gl_FragColor_assigned = false;
+ bool gl_FragData_assigned = false;
+ bool user_defined_fs_output_assigned = false;
+ ir_variable *user_defined_fs_output = NULL;
+
+ /* It would be nice to have proper location information. */
+ YYLTYPE loc;
+ memset(&loc, 0, sizeof(loc));
+
+ foreach_list(node, instructions) {
+ ir_variable *var = ((ir_instruction *)node)->as_variable();
+
+ if (!var || !var->assigned)
+ continue;
+
+ if (strcmp(var->name, "gl_FragColor") == 0)
+ gl_FragColor_assigned = true;
+ else if (strcmp(var->name, "gl_FragData") == 0)
+ gl_FragData_assigned = true;
+ else if (strncmp(var->name, "gl_", 3) != 0) {
+ if (state->target == fragment_shader &&
+ var->mode == ir_var_shader_out) {
+ user_defined_fs_output_assigned = true;
+ user_defined_fs_output = var;
+ }
+ }
+ }
+
+ /* From the GLSL 1.30 spec:
+ *
+ * "If a shader statically assigns a value to gl_FragColor, it
+ * may not assign a value to any element of gl_FragData. If a
+ * shader statically writes a value to any element of
+ * gl_FragData, it may not assign a value to
+ * gl_FragColor. That is, a shader may assign values to either
+ * gl_FragColor or gl_FragData, but not both. Multiple shaders
+ * linked together must also consistently write just one of
+ * these variables. Similarly, if user declared output
+ * variables are in use (statically assigned to), then the
+ * built-in variables gl_FragColor and gl_FragData may not be
+ * assigned to. These incorrect usages all generate compile
+ * time errors."
+ */
+ if (gl_FragColor_assigned && gl_FragData_assigned) {
+ _mesa_glsl_error(&loc, state, "fragment shader writes to both "
+ "`gl_FragColor' and `gl_FragData'\n");
+ } else if (gl_FragColor_assigned && user_defined_fs_output_assigned) {
+ _mesa_glsl_error(&loc, state, "fragment shader writes to both "
+ "`gl_FragColor' and `%s'\n",
+ user_defined_fs_output->name);
+ } else if (gl_FragData_assigned && user_defined_fs_output_assigned) {
+ _mesa_glsl_error(&loc, state, "fragment shader writes to both "
+ "`gl_FragData' and `%s'\n",
+ user_defined_fs_output->name);
+ }
+}