+#define arch_irn_is(env, irn, flag) ((arch_irn_get_flags(env, irn) & arch_irn_flags_ ## flag) != 0)
+
+#define arch_irn_has_reg_class(env, irn, pos, cls) \
+ ((cls) == arch_get_irn_reg_class(env, irn, pos))
+
+#define arch_irn_consider_in_reg_alloc(env, cls, irn) \
+ (arch_irn_has_reg_class(env, irn, -1, cls) && !arch_irn_is(env, irn, ignore))
+
+/**
+ * Somebody who can be asked about IR nodes.
+ */
+struct _arch_irn_handler_t {
+
+ /**
+ * Get the operations of an irn.
+ * @param self The handler from which the method is invoked.
+ * @param irn Some node.
+ * @return Operations for that irn.
+ */
+ const void *(*get_irn_ops)(const arch_irn_handler_t *handler,
+ const ir_node *irn);
+};
+
+/**
+ * The code generator interface.
+ */
+struct _arch_code_generator_if_t {
+ /**
+ * Initialize the code generator.
+ * @param birg A backend IRG session.
+ * @return A newly created code generator.
+ */
+ void *(*init)(const be_irg_t *birg);
+
+ /**
+ * Called before abi introduce.
+ */
+ void (*before_abi)(void *self);
+
+ /**
+ * Called, when the graph is being normalized.
+ */
+ void (*prepare_graph)(void *self);
+
+ /**
+ * Called before scheduling.
+ */
+ void (*before_sched)(void *self);
+
+ /**
+ * Called before register allocation.
+ */
+ void (*before_ra)(void *self);
+
+ /**
+ * Called after register allocation.
+ */
+ void (*after_ra)(void *self);
+
+ /**
+ * Called after everything happened.
+ * The code generator must also be de-allocated here.
+ */
+ void (*done)(void *self);
+};
+
+/**
+ * helper macro: call function func from the code generator
+ * if it's implemented.
+ */
+#define _arch_cg_call(cg, func) \
+do { \
+ if((cg)->impl->func) \
+ (cg)->impl->func(cg); \
+} while(0)
+
+#define arch_code_generator_before_abi(cg) _arch_cg_call(cg, before_abi)
+#define arch_code_generator_prepare_graph(cg) _arch_cg_call(cg, prepare_graph)
+#define arch_code_generator_before_sched(cg) _arch_cg_call(cg, before_sched)
+#define arch_code_generator_before_ra(cg) _arch_cg_call(cg, before_ra)
+#define arch_code_generator_after_ra(cg) _arch_cg_call(cg, after_ra)
+#define arch_code_generator_done(cg) _arch_cg_call(cg, done)
+
+/**
+ * Code generator base class.
+ */
+struct _arch_code_generator_t {
+ const arch_code_generator_if_t *impl;
+};
+
+/**
+ * ISA base class.
+ */
+struct _arch_isa_t {
+ const arch_isa_if_t *impl;
+ const arch_register_t *sp; /** The stack pointer register. */
+ const arch_register_t *bp; /** The base pointer register. */
+ const int stack_dir; /** -1 for decreasing, 1 for increasing. */
+};
+
+#define arch_isa_stack_dir(isa) ((isa)->stack_dir)
+#define arch_isa_sp(isa) ((isa)->sp)
+#define arch_isa_bp(isa) ((isa)->bp)
+
+/**
+ * Architecture interface.
+ */
+struct _arch_isa_if_t {
+
+ /**
+ * Initialize the isa interface.
+ * @param file_handle the file handle to write the output to
+ * @return a new isa instance
+ */
+ void *(*init)(FILE *file_handle);
+
+ /**
+ * Free the isa instance.
+ */
+ void (*done)(void *self);
+
+ /**
+ * Get the the number of register classes in the isa.
+ * @return The number of register classes.
+ */
+ int (*get_n_reg_class)(const void *self);
+
+ /**
+ * Get the i-th register class.
+ * @param i The number of the register class.
+ * @return The register class.
+ */
+ const arch_register_class_t *(*get_reg_class)(const void *self, int i);
+
+ /**
+ * Get the register class which shall be used to store a value of a given mode.
+ * @param self The this pointer.
+ * @param mode The mode in question.
+ * @return A register class which can hold values of the given mode.
+ */
+ const arch_register_class_t *(*get_reg_class_for_mode)(const void *self, const ir_mode *mode);
+
+ /**
+ * Get the ABI restrictions for procedure calls.
+ * @param self The this pointer.
+ * @param method_type The type of the method (procedure) in question.
+ * @param p The array of parameter locations to be filled.
+ */
+ void (*get_call_abi)(const void *self, ir_type *method_type, be_abi_call_t *abi);
+
+ /**
+ * The irn handler for this architecture.
+ * The irn handler is registered by the Firm back end
+ * when the architecture is initialized.
+ * (May be NULL).
+ */
+ const arch_irn_handler_t *(*get_irn_handler)(const void *self);
+
+ /**
+ * Get the code generator interface.
+ * @param self The this pointer.
+ * @return Some code generator interface.
+ */
+ const arch_code_generator_if_t *(*get_code_generator_if)(void *self);
+
+ /**
+ * Get the list scheduler to use.
+ * @param self The isa object.
+ * @return The list scheduler selector.
+ */
+ const list_sched_selector_t *(*get_list_sched_selector)(const void *self);
+
+ /**
+ * Get the necessary alignment for storing a register of given class.
+ * @param self The isa object.
+ * @param cls The register class.
+ * @return The alignment in bytes.
+ */
+ int (*get_reg_class_alignment)(const void *self, const arch_register_class_t *cls);
+
+#ifdef WITH_LIBCORE
+ /**
+ * Register command line options for this backend.
+ * @param grp The root group.
+ */
+ void (*register_options)(lc_opt_entry_t *grp);