exchange Perm-Proj, instead of rerouting

ir/be/belower.c

@@ -338,8 +338,9 @@ static void lower_perm_node(ir_node *irn, void *walk_env) {
 			sched_remove(pairs[i].out_node);
 
 			/* reroute the edges from the proj to the argument */
-			edges_reroute(pairs[i].out_node, pairs[i].in_node, env->birg->irg);
-			set_irn_n(pairs[i].out_node, 0, new_Bad());
+			exchange(pairs[i].out_node, pairs[i].in_node);
+			//edges_reroute(pairs[i].out_node, pairs[i].in_node, env->birg->irg);
+			//set_irn_n(pairs[i].out_node, 0, new_Bad());
 
 			pairs[i].checked = 1;
 		}