ir_node *sched_prev(const ir_node *irn);
ir_node *sched_first(const ir_node *block);
ir_node *sched_last(const ir_node *block);
-ir_node *sched_add_before(ir_node *before, ir_node *irn);
-ir_node *sched_add_after(ir_node *before, ir_node *irn);
+void sched_add_before(ir_node *before, ir_node *irn);
+void sched_add_after(ir_node *before, ir_node *irn);
void sched_init_block(ir_node *block);
void sched_reset(ir_node *node);
void sched_remove(ir_node *irn);