+void set_op_pinned(ir_op *op, op_pin_state pinned);
+
+/** Returns the next free IR opcode number, allows to register user ops */
+unsigned get_next_ir_opcode(void);
+
+/** Returns the next free n IR opcode number, allows to register a bunch of user ops */
+unsigned get_next_ir_opcodes(unsigned num);
+
+/**
+ * A generic function pointer.
+ */
+typedef void (*op_func)(void);
+
+/** The NULL-function. */
+#define NULL_FUNC ((generic_func)(NULL))
+
+/**
+ * Returns the generic function pointer from an ir operation.
+ */
+op_func get_generic_function_ptr(const ir_op *op);
+
+/**
+ * Store a generic function pointer into an ir operation.
+ */
+void set_generic_function_ptr(ir_op *op, op_func func);
+
+/**
+ * The compute value operation.
+ * This operation evaluates an IR node into a tarval if possible,
+ * returning tarval_bad otherwise.
+ */
+typedef tarval *(*computed_value_func)(ir_node *self);
+
+/**
+ * The equivalent node operation.
+ * This operation returns an equivalent node for the input node.
+ * It does not create new nodes. It is therefore safe to free self
+ * if the node returned is not self.
+ * If a node returns a Tuple we can not just skip it. If the size of the
+ * in array fits, we transform n into a tuple (e.g., possible for Div).
+ */
+typedef ir_node *(*equivalent_node_func)(ir_node *self);
+
+/**
+ * The transform node operation.
+ * This operation tries several [inplace] [optimizing] transformations
+ * and returns an equivalent node.
+ * The difference to equivalent_node() is that these
+ * transformations _do_ generate new nodes, and thus the old node must
+ * not be freed even if the equivalent node isn't the old one.
+ */
+typedef ir_node *(*transform_node_func)(ir_node *self);
+
+/**
+ * The node attribute compare operation.
+ * Compares the nodes attributes of two nodes of identical opcode
+ * and returns 0 if the attributes are identical, 1 if they differ.
+ */
+typedef int (*node_cmp_attr_func)(ir_node *a, ir_node *b);
+
+/**
+ * The reassociation operation.
+ * Called from a walker. Returns non-zero if
+ * a reassociation rule was applied.
+ * The pointer n is set to the newly created node, if some reassociation
+ * was applied.
+ */
+typedef int (*reassociate_func)(ir_node **n);
+
+/**
+ * The copy attribute operation.
+ * Copy the node attributes from a 'old' node to a 'new' one.
+ */
+typedef void (*copy_attr_func)(const ir_node *old_node, ir_node *new_node);
+
+/**
+ * The get_type operation.
+ * Return the type of the node self.
+ */
+typedef ir_type *(*get_type_func)(ir_node *self);
+
+/**
+ * The get_type_attr operation. Used to traverse all types that can be
+ * accessed from an ir_graph.
+ * Return the type attribute of the node self.
+ */
+typedef ir_type *(*get_type_attr_func)(ir_node *self);
+
+/**
+ * The get_entity_attr operation. Used to traverse all entities that can be
+ * accessed from an ir_graph.
+ * Return the entity attribute of the node self.
+ */
+typedef entity *(*get_entity_attr_func)(ir_node *self);
+
+/**
+ * The verify_node operation.
+ * Return non-zero if the node verification is ok, else 0.
+ * Depending on the node verification settings, may even assert.
+ *
+ * @see do_node_verification()
+ */
+typedef int (*verify_node_func)(ir_node *self, ir_graph *irg);
+
+/**
+ * The verify_node operation for Proj(X).
+ * Return non-zero if the node verification is ok, else 0.
+ * Depending on the node verification settings, may even assert.
+ *
+ * @see do_node_verification()
+ */
+typedef int (*verify_proj_node_func)(ir_node *self, ir_node *proj);
+
+/**
+ * Reasons to call the dump_node operation:
+ */
+typedef enum {
+ dump_node_opcode_txt, /**< dump the opcode */
+ dump_node_mode_txt, /**< dump the mode */
+ dump_node_nodeattr_txt, /**< dump node attributes to be shown in the label */
+ dump_node_info_txt /**< dump node attributes into info1 */
+} dump_reason_t;
+
+/**
+ * The dump_node operation.
+ * Writes several informations requested by reason to
+ * an output file
+ */
+typedef int (*dump_node_func)(ir_node *self, FILE *F, dump_reason_t reason);