+/** Dump a node and its predecessors forming a subgraph to a vcg file.
+ *
+ * @param root The node serving as root for the subgraph.
+ * @param depth Dump nodes on paths starting at root with length depth.
+ * @param suffix A suffix for the file name.
+ *
+ * Dumps the graph to a file. The file name is constructed from the
+ * name of the entity describing the procedure the passed node is
+ * in, suffix and the ending -subg_<nr>.vcg. nr is a unique number
+ * for each graph dumped. Eventually overwrites existing files.
+ *
+ * @return
+ * A file containing the subgraph in vcg format.
+ */
+void dump_subgraph (ir_node *root, int depth, const char *suffix);