+/**
+ * Datatype of the generic op handler for optimisation.
+ */
+typedef void (*peephole_opt_func) (ir_node *node);
+
+/**
+ * must be called from peephole optimisations before a node is exchanged,
+ * so bepeephole can update it's internal state.
+ */
+void be_peephole_before_exchange(const ir_node *old_node, ir_node *new_node);
+
+/**
+ * must be called from peephole optimisations after a node is exchanged,
+ * so bepeephole can update it's internal state.
+ */
+void be_peephole_after_exchange(ir_node *new_node);