+/** Control flow optimization.
+ * Removes empty blocks doing if simplifications and loop simplifications.
+ * A block is empty if it contains only a Jmp node and Phi nodes.
+ * Merges single entry single exit blocks with their predecessor
+ * and propagates dead control flow by calling equivalent_node.
+ * Independent of compiler flag it removes Tuples from cf edges,
+ * Bad predecessors form blocks and unnecessary predecessors of End.
+ *
+ * @bug So far destroys backedge information.
+ * @bug Chokes on Id nodes if called in a certain order with other
+ * optimizations. Call local_optimize_graph before to remove
+ * Ids.
+ */
+void optimize_cf(ir_graph *irg);
+