+/** Applies local optimizations (see iropt.h) to all nodes in the graph.
+ *
+ * @param irg The graph to be optimized.
+ *
+ * After applying local_optimize_graph() to a IR-graph, Bad nodes
+ * only occure as predecessor of Block and Phi nodes.
+ *
+ * This version used a fixpoint iteration.
+ */
+void optimize_graph_df(ir_graph *irg);
+