+ * Get the string representation of a flag.
+ * This functions does not handle or'ed bitmasks of flags.
+ * @param flag The flag.
+ * @return The flag as a string.
+ */
+extern const char *arch_irn_flag_str(arch_irn_flags_t flag);
+
+struct _arch_irn_ops_if_t {
+
+ /**
+ * Get the register requirements for a given operand.
+ * @param self The self pointer.
+ * @param irn The node.
+ * @param pos The operand's position
+ * (-1 for the result of the node, 0..n for the input operands).
+ * @return The register requirements for the selected operand.
+ * The pointer returned is never NULL.
+ */
+ const arch_register_req_t *(*get_irn_reg_req)(const void *self,
+ const ir_node *irn, int pos);
+
+ /**
+ * Set the register for an output operand.
+ * @param irn The node.
+ * @param reg The register allocated to that operand.
+ * @note If the operand is not a register operand,
+ * the call is ignored.
+ */
+ void (*set_irn_reg)(const void *self, ir_node *irn, const arch_register_t *reg);
+
+ /**
+ * Get the register allocated for an output operand.
+ * @param irn The node.
+ * @return The register allocated at that operand. NULL, if
+ * the operand was no register operand or
+ * @c arch_register_invalid, if no register has yet been
+ * allocated for this node.
+ */
+ const arch_register_t *(*get_irn_reg)(const void *self, const ir_node *irn);
+
+ /**
+ * Classify the node.
+ * @param irn The node.
+ * @return A classification.
+ */
+ arch_irn_class_t (*classify)(const void *self, const ir_node *irn);
+
+ /**
+ * Get the flags of a node.
+ * @param self The irn ops themselves.
+ * @param irn The node.
+ * @return A set of flags.
+ */
+ arch_irn_flags_t (*get_flags)(const void *self, const ir_node *irn);
+
+ /**
+ * Get the entity on the stack frame this node depends on.
+ * @param self The this pointer.
+ * @param irn The node in question.
+ * @return The entity on the stack frame or NULL, if the node does not have a
+ * stack frame entity.
+ */
+ ir_entity *(*get_frame_entity)(const void *self, const ir_node *irn);
+
+ /**
+ * Set the entity on the stack frame this node depends on.
+ * @param self The this pointer.
+ * @param irn The node in question.
+ * @param ent The entity to set
+ */
+ void (*set_frame_entity)(const void *self, ir_node *irn, ir_entity *ent);
+
+ /**
+ * Set the offset of a node carrying an entity on the stack frame.
+ * @param self The this pointer.
+ * @param irn The node.
+ * @param offset The offset of the node's stack frame entity.
+ */
+ void (*set_frame_offset)(const void *self, ir_node *irn, int offset);
+
+ /**
+ * Returns the delta of the stackpointer for nodes that increment or
+ * decrement the stackpointer with a constant value. (push, pop
+ * nodes on most architectures).
+ * A positive value stands for an expanding stack area, a negative value for
+ * a shrinking one.
+ *
+ * @param self The this pointer
+ * @param irn The node
+ * @return 0 if the stackpointer is not modified with a constant
+ * value, otherwise the increment/decrement value
+ */
+ int (*get_sp_bias)(const void *self, const ir_node *irn);
+
+ /**
+ * Returns an inverse operation which yields the i-th argument
+ * of the given node as result.
+ *
+ * @param self The this pointer.
+ * @param irn The original operation
+ * @param i Index of the argument we want the inverse operation to yield
+ * @param inverse struct to be filled with the resulting inverse op
+ * @param obstack The obstack to use for allocation of the returned nodes array
+ * @return The inverse operation or NULL if operation invertible
+ */
+ arch_inverse_t *(*get_inverse)(const void *self, const ir_node *irn, int i, arch_inverse_t *inverse, struct obstack *obstack);
+
+ /**
+ * Get the estimated cycle count for @p irn.
+ *
+ * @param self The this pointer.
+ * @param irn The node.
+ *
+ * @return The estimated cycle count for this operation
+ */
+ int (*get_op_estimated_cost)(const void *self, const ir_node *irn);
+
+ /**
+ * Asks the backend whether operand @p i of @p irn can be loaded form memory internally
+ *
+ * @param self The this pointer.
+ * @param irn The node.
+ * @param i Index of the argument we would like to know whether @p irn can load it form memory internally
+ *
+ * @return nonzero if argument can be loaded or zero otherwise
+ */
+ int (*possible_memory_operand)(const void *self, const ir_node *irn, unsigned int i);
+
+ /**
+ * Ask the backend to assimilate @p reload of operand @p i into @p irn.
+ *
+ * @param self The this pointer.
+ * @param irn The node.
+ * @param spill The spill.
+ * @param i The position of the reload.
+ */
+ void (*perform_memory_operand)(const void *self, ir_node *irn, ir_node *spill, unsigned int i);
+};