+/**
+ * Returns the smallest common dominator block of two nodes.
+ * @param a A node.
+ * @param b Another node.
+ * @return The first block dominating @p a and @p b
+ */
+ir_node *node_smallest_common_dominator(ir_node *a, ir_node *b);
+
+/**
+ * Returns the smallest common dominator block of all users of a node
+ * BEWARE: @p irn must not be a block
+ * If on or more users are Phi nodes, one can request special handling
+ * with @p handle_phi = 1. In this case the cfg predecessor block
+ * corresponding to the position of the irn in the argument list of the
+ * Phi is determined and treated as user.
+ *
+ * @param irn A node.
+ * @param handle_phi 1 if Phis should be handled different
+ * @return The first block dominating all users of @irn
+ */
+ir_node *node_users_smallest_common_dominator(ir_node *irn, int handle_phi);
+
+/**
+ * Check, if a block post dominates another block.
+ * @param a The first block.
+ * @param b The second block.
+ * @return 1, if @p a post dominates @p b, else 0.
+ */
+int block_postdominates(const ir_node *a, const ir_node *b);
+
+/**
+ * Visit all nodes in the dominator subtree of a given node.
+ * Call a pre-visitor before descending to the children and call a
+ * post-visitor after returning from them.
+ * @param n The node to start walking from.
+ * @param pre The pre-visitor callback.
+ * @param post The post-visitor callback.
+ * @param env Some custom data passed to the visitors.
+ */
+void dom_tree_walk(ir_node *n, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
+
+/**
+ * Visit all nodes in the post dominator subtree of a given node.
+ * Call a pre-visitor before descending to the children and call a
+ * post-visitor after returning from them.
+ * @param n The node to start walking from.
+ * @param pre The pre-visitor callback.
+ * @param post The post-visitor callback.
+ * @param env Some custom data passed to the visitors.
+ */
+void postdom_tree_walk(ir_node *n, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
+
+/**
+ * Walk over the dominator tree of an irg starting at the root.
+ * @param irg The graph.
+ * @param pre A pre-visitor to call.
+ * @param post A post-visitor to call.
+ * @param env Some private data to give to the visitors.
+ */
+void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
+
+/**
+ * Walk over the post dominator tree of an irg starting at the root.
+ * @param irg The graph.
+ * @param pre A pre-visitor to call.
+ * @param post A post-visitor to call.
+ * @param env Some private data to give to the visitors.
+ */
+void postdom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
+
+/* ------------ Building and Removing the dominator data structure ----------- */
+
+/** Computes the dominator trees.
+ *
+ * Sets a flag in irg to "dom_consistent".
+ * If the control flow of the graph is changed this flag must be set to
+ * "dom_inconsistent".
+ * Does not compute dominator information for control dead code. Blocks
+ * not reachable from Start contain the following information:
+ * @code
+ * idom = NULL;
+ * dom_depth = -1;
+ * pre_num = -1;
+ * @endcode
+ * Also constructs outs information. As this information is correct after
+ * the run does not free the outs information.
+ */