IR variable: Initial work to support GLSL built-in variables

ir_variable.cpp

@@ -0,0 +1,144 @@
+/*
+ * Copyright © 2010 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "glsl_parser_extras.h"
+#include "symbol_table.h"
+#include "ir.h"
+#include "builtin_variables.h"
+
+#ifndef Elements
+#define Elements(x) (sizeof(x)/sizeof(*(x)))
+#endif
+
+static void
+add_builtin_variable(const builtin_variable *proto, exec_list *instructions,
+		     struct _mesa_symbol_table *symtab)
+{
+   /* Create a new variable declaration from the description supplied by
+    * the caller.
+    */
+   const glsl_type *const type = (glsl_type *)
+      _mesa_symbol_table_find_symbol(symtab, 0, proto->type);
+
+   assert(type != NULL);
+
+   ir_variable *var = new ir_variable(type, proto->name);
+
+   var->mode = proto->mode;
+   if (var->mode != ir_var_out)
+      var->read_only = true;
+
+
+   /* Once the variable is created an initialized, add it to the symbol table
+    * and add the declaration to the IR stream.
+    */
+   instructions->push_tail(var);
+
+   _mesa_symbol_table_add_symbol(symtab, 0, var->name, var);
+}
+
+
+static void
+generate_110_vs_variables(exec_list *instructions,
+			  struct _mesa_symbol_table *symtab)
+{
+   for (unsigned i = 0; i < Elements(builtin_core_vs_variables); i++) {
+      add_builtin_variable(& builtin_core_vs_variables[i],
+			   instructions, symtab);
+   }
+
+   for (unsigned i = 0
+	   ; i < Elements(builtin_110_deprecated_vs_variables)
+	   ; i++) {
+      add_builtin_variable(& builtin_110_deprecated_vs_variables[i],
+			   instructions, symtab);
+   }
+
+   /* FINISHME: Add support fo gl_TexCoord.  The size of this array is
+    * FINISHME: implementation dependent based on the value of
+    * FINISHME: GL_MAX_TEXTURE_COORDS.
+    */
+}
+
+
+static void
+generate_120_vs_variables(exec_list *instructions,
+			  struct _mesa_symbol_table *symtab)
+{
+   /* GLSL version 1.20 did not add any built-in variables in the vertex
+    * shader.
+    */
+   generate_110_vs_variables(instructions, symtab);
+}
+
+
+static void
+generate_130_vs_variables(exec_list *instructions,
+			  struct _mesa_symbol_table *symtab)
+{
+   generate_120_vs_variables(instructions, symtab);
+
+   for (unsigned i = 0; i < Elements(builtin_130_vs_variables); i++) {
+      add_builtin_variable(& builtin_130_vs_variables[i],
+			   instructions, symtab);
+   }
+
+   /* FINISHME: Add support fo gl_ClipDistance.  The size of this array is
+    * FINISHME: implementation dependent based on the value of
+    * FINISHME: GL_MAX_CLIP_DISTANCES.
+    */
+}
+
+
+static void
+initialize_vs_variables(exec_list *instructions,
+			struct _mesa_glsl_parse_state *state)
+{
+
+   switch (state->language_version) {
+   case 110:
+      generate_110_vs_variables(instructions, state->symbols);
+      break;
+   case 120:
+      generate_120_vs_variables(instructions, state->symbols);
+      break;
+   case 130:
+      generate_130_vs_variables(instructions, state->symbols);
+      break;
+   }
+}
+
+
+void
+_mesa_glsl_initialize_variables(exec_list *instructions,
+				struct _mesa_glsl_parse_state *state)
+{
+   switch (state->target) {
+   case vertex_shader:
+      initialize_vs_variables(instructions, state);
+      break;
+   case geometry_shader:
+   case fragment_shader:
+      break;
+   }
+}