glsl2: Add function to import function prototypes from one IR tree to another

src/glsl/Makefile

@@ -49,6 +49,7 @@ CXX_SOURCES = \
 	ir_if_return.cpp \
 	ir_if_simplification.cpp \
 	ir_if_to_cond_assign.cpp \
+	ir_import_prototypes.cpp \
 	ir_mat_op_to_vec.cpp \
 	ir_mod_to_fract.cpp \
 	ir_print_visitor.cpp \

src/glsl/ir.h

@@ -1318,4 +1318,10 @@ _mesa_glsl_initialize_functions(exec_list *instructions,
 extern void
 reparent_ir(exec_list *list, void *mem_ctx);
 
+class glsl_symbol_table;
+
+extern void
+import_prototypes(const exec_list *source, exec_list *dest,
+		  class glsl_symbol_table *symbols, void *mem_ctx);
+
 #endif /* IR_H */

src/glsl/ir_import_prototypes.cpp

@@ -0,0 +1,137 @@
+/*
+ * 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.
+ */
+
+/**
+ * \file ir_import_prototypes.cpp
+ * Import function prototypes from one IR tree into another.
+ *
+ * \author Ian Romanick
+ */
+#include <cstdio>
+#include "ir.h"
+#include "glsl_symbol_table.h"
+
+/**
+ * Visitor used to import function prototypes
+ *
+ * Normally the \c clone method of either \c ir_function or
+ * \c ir_function_signature could be used.  However, we don't want a complete
+ * clone of the \c ir_function_signature.  We want everything \b except the
+ * body of the function.
+ */
+class import_prototype_visitor : public ir_hierarchical_visitor {
+public:
+   /**
+    */
+   import_prototype_visitor(exec_list *list, glsl_symbol_table *symbols,
+			    void *mem_ctx)
+   {
+      this->mem_ctx = mem_ctx;
+      this->list = list;
+      this->symbols = symbols;
+      this->function = NULL;
+   }
+
+   virtual ir_visitor_status visit_enter(ir_function *ir)
+   {
+      assert(this->function == NULL);
+      this->function = new(this->mem_ctx) ir_function(ir->name);
+      return visit_continue;
+   }
+
+   virtual ir_visitor_status visit_leave(ir_function *ir)
+   {
+      (void) ir;
+      assert(this->function != NULL);
+
+      /* Add the new function (and all its signatures) to the end of the
+       * instruction stream.
+       */
+      list->push_tail(this->function);
+
+      /* Add the new function to the symbol table.
+       */
+      this->symbols->add_function(this->function->name, this->function);
+
+      this->function = NULL;
+      return visit_continue;
+   }
+
+   ir_visitor_status visit_enter(ir_function_signature *ir)
+   {
+      assert(this->function != NULL);
+
+      ir_function_signature *copy =
+	 new(mem_ctx) ir_function_signature(ir->return_type);
+
+      copy->is_defined = false;
+      copy->is_built_in = ir->is_built_in;
+
+      /* Clone the parameter list, but NOT the body.
+       */
+      foreach_list_const(node, &ir->parameters) {
+	 const ir_variable *const param = (const ir_variable *) node;
+
+	 assert(const_cast<ir_variable *>(param)->as_variable() != NULL);
+
+	 ir_variable *const param_copy = param->clone(NULL);
+	 copy->parameters.push_tail(param_copy);
+      }
+
+      this->function->add_signature(copy);
+
+      /* Do not process child nodes of the ir_function_signature.  There can
+       * never be any nodes inside the ir_function_signature that we care
+       * about.  Instead continue with the next sibling.
+       */
+      return visit_continue_with_parent;
+   }
+
+private:
+   exec_list *list;
+   ir_function *function;
+   glsl_symbol_table *symbols;
+   void *mem_ctx;
+};
+
+
+/**
+ * Import function prototypes from one IR tree into another
+ *
+ * \param source   Source instruction stream containing functions whose
+ *                 prototypes are to be imported
+ * \param dest     Destination instruction stream where new \c ir_function and
+ *                 \c ir_function_signature nodes will be stored
+ * \param symbols  Symbol table where new functions will be stored
+ * \param mem_ctx  talloc memory context used for new allocations
+ */
+void
+import_prototypes(const exec_list *source, exec_list *dest,
+		  glsl_symbol_table *symbols, void *mem_ctx)
+{
+   import_prototype_visitor v(dest, symbols, mem_ctx);
+
+   /* Making source be const is just extra documentation.
+    */
+   v.run(const_cast<exec_list *>(source));
+}