+/**
+ * Creates a new value table used for storing CSE identities.
+ * The value table is used to identify common expressions.
+ */
+void new_identities(ir_graph *irg);
+
+/**
+ * Deletes a identities value table.
+ *
+ * @param value_table the identity set
+ */
+void del_identities(ir_graph *irg);
+
+/**
+ * Add a node to the identities value table.
+ */
+void add_identities(ir_node *node);
+
+/**
+ * Compare function for two nodes in the hash table. Gets two
+ * nodes as parameters. Returns 0 if the nodes are a cse.
+ */
+int identities_cmp(const void *elt, const void *key);
+
+/**
+ * Return the canonical node computing the same value as n.
+ * Looks up the node in a hash table, enters it in the table
+ * if it isn't there yet.
+ */
+ir_node *identify_remember(ir_node *n);
+
+/** Visit each node in the value table of a graph. */
+void visit_all_identities(ir_graph *irg, irg_walk_func visit, void *env);
+
+/**
+ * Normalize a node by putting constants (and operands with larger
+ * node index) on the right (operator side).
+ *
+ * @param n The node to normalize
+ */
+void ir_normalize_node(ir_node *n);
+
+ir_node *optimize_node(ir_node *n);
+
+ir_node *optimize_in_place_2(ir_node *n);
+
+/**
+ * The value_of operation.
+ * This operation returns for every IR node an associated tarval if existing,
+ * returning tarval_bad otherwise.
+ * No calculations are done here, just a lookup.
+ */
+typedef ir_tarval *(*value_of_func)(const ir_node *self);
+
+extern value_of_func value_of_ptr;
+
+/**
+ * Set a new value_of function.
+ *
+ * @param func the function, NULL restores the default behavior
+ */
+void set_value_of_func(value_of_func func);
+
+/**
+ * Returns the associated tarval of a node.
+ */
+static inline ir_tarval *value_of(const ir_node *n)
+{
+ return value_of_ptr(n);
+}
+
+/**
+ * Sets the default operations for an ir_op_ops.
+ *
+ * @param code the opcode for the default operation
+ * @param ops the operations initialized
+ *
+ * @return
+ * The operations.
+ */
+ir_op_ops *firm_set_default_operations(unsigned code, ir_op_ops *ops);
+
+/**
+ * Returns true if a == -b
+ */
+bool is_negated_value(ir_node *a, ir_node *b);
+
+
+
+/** NOTE: Survive DCE is considered a bad hack - don't use */
+typedef struct survive_dce_t survive_dce_t;
+
+/**
+ * Make a new Survive DCE environment.
+ * NOTE: Survive DCE is considered a bad hack - don't use
+ */
+survive_dce_t *new_survive_dce(void);
+
+/**
+ * Free a Survive DCE environment.
+ * NOTE: Survive DCE is considered a bad hack - don't use
+ */
+void free_survive_dce(survive_dce_t *sd);
+
+/**
+ * Register a node pointer to be patched upon DCE.
+ * When DCE occurs, the node pointer specified by @p place will be
+ * patched to the new address of the node it is pointing to.
+ *
+ * @param sd The Survive DCE environment.
+ * @param place The address of the node pointer.
+ */
+void survive_dce_register_irn(survive_dce_t *sd, ir_node **place);
+
+#endif