+/** Returns a unique node number for the loop node to make output
+ readable. If libfirm_debug is not set it returns the loop cast to
+ int. */
+int get_loop_loop_nr(ir_loop *loop);
+
+/** A field to connect additional information to a loop. Only valid
+ if libfirm_debug is set, else returns NULL. */
+void set_loop_link (ir_loop *loop, void *link);
+void *get_loop_link (const ir_loop *loop);
+
+/* ------------------------------------------------------------------- */
+/* Constructing and destructing the loop/backedge information. */
+/* ------------------------------------------------------------------- */
+
+/** Constructs backedge information and loop tree for a graph in intraprocedural view.
+ *
+ * The algorithm views the program representation as a pure graph.
+ * It assumes that only block and phi nodes may be loop headers.
+ * The resulting loop tree is a possible visiting order for dataflow
+ * analysis.
+ *
+ * @returns Maximal depth of loop tree.
+ *
+ * @remark
+ * One assumes, the Phi nodes in a block with a backedge have backedges
+ * at the same positions as the block. This is not the case, as
+ * the scc algorithms does not respect the program semantics in this case.
+ * Take a swap in a loop (t = i; i = j; j = t;) This results in two Phi
+ * nodes. They form a cycle. Once the scc algorithm deleted one of the
+ * edges, the cycle is removed. The second Phi node does not get a
+ * backedge!
+ */