+/**
+ * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
+ *
+ * @return number of visited nodes
+ */
+static unsigned irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env)
+{
+ int i;
+ unsigned cnt = 1;
+ ir_graph *irg = get_irn_irg(node);
+
+ set_irn_visited(node, irg->visited);
+
+ pre(node, env);
+
+ if (node->op != op_Block) {
+ ir_node *pred = get_irn_n(node, -1);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
+ }
+ for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
+ ir_node *pred = get_irn_in_or_dep(node, i);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
+ }
+ return cnt;
+}
+
+/**
+ * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
+ *
+ * @return number of visited nodes
+ */
+static unsigned irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env)
+{
+ int i;
+ unsigned cnt = 1;
+ ir_graph *irg = get_irn_irg(node);
+
+ set_irn_visited(node, irg->visited);
+
+ if (node->op != op_Block) {
+ ir_node *pred = get_irn_n(node, -1);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_post(pred, post, env);
+ }
+ for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
+ ir_node *pred = get_irn_in_or_dep(node, i);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_post(pred, post, env);
+ }
+
+ post(node, env);
+
+ return cnt;
+}
+
+/**
+ * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
+ *
+ * @return number of visited nodes
+ */
+static unsigned irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
+{
+ int i;
+ unsigned cnt = 1;
+ ir_graph *irg = get_irn_irg(node);
+
+ set_irn_visited(node, irg->visited);
+
+ pre(node, env);
+
+ if (node->op != op_Block) {
+ ir_node *pred = get_irn_n(node, -1);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
+ }
+ for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
+ ir_node *pred = get_irn_in_or_dep(node, i);
+ if (pred->visited < irg->visited)
+ cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
+ }
+
+ post(node, env);
+
+ return cnt;
+}
+
+/**
+ * Intraprozedural graph walker. Follows dependency edges as well.
+ *
+ * @return number of visited nodes
+ */
+static unsigned irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
+{
+ if (irn_visited(node))
+ return 0;
+
+ if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
+ else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
+ else return irg_walk_in_or_dep_2_both(node, pre, post, env);
+}
+
+/*
+ * Generic graph walker. Follows dependency edges as well.
+ */
+void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
+{
+ assert(is_ir_node(node));
+
+ ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
+ inc_irg_visited(current_ir_graph);
+ nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
+ ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
+}
+
+/*
+ * Walk over a graph. Follow all edges (including dependencies)
+ */
+void irg_walk_in_or_dep_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
+{
+ ir_graph * rem = current_ir_graph;
+
+ hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
+ current_ir_graph = irg;
+ irg_walk_in_or_dep(get_irg_end(irg), pre, post, env);
+ irg->estimated_node_count = nodes_touched;
+ current_ir_graph = rem;
+}
+
+/***************************************************************************/
+
+/* Walks back from n until it finds a real cf op. */
+static ir_node *get_cf_op(ir_node *n)
+{
+ while (!is_cfop(n) && !is_fragile_op(n) && !is_Bad(n)) {
+ n = skip_Id(n);
+ n = skip_Tuple(n);
+ n = skip_Proj(n);
+ }
+ return n;
+}
+
+static void irg_block_walk_2(ir_node *node, irg_walk_func *pre,
+ irg_walk_func *post, void *env)
+{
+ int i;
+
+ if (Block_block_visited(node))
+ return;
+ mark_Block_block_visited(node);
+
+ if (pre)
+ pre(node, env);
+
+ for (i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
+ /* find the corresponding predecessor block. */
+ ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
+ pred = get_nodes_block(pred);
+ if (get_irn_opcode(pred) == iro_Block) {
+ /* recursion */
+ irg_block_walk_2(pred, pre, post, env);
+ } else {
+ assert(get_irn_opcode(pred) == iro_Bad);
+ }
+ }
+
+ if (post)
+ post(node, env);