+ /**
+ * 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)(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 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 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 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 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)(ir_node *irn, ir_node *spill, unsigned int i);
+};
+
+/**
+ * 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)(be_irg_t *birg);
+
+ /**
+ * return node used as base in pic code addresses
+ */
+ ir_node* (*get_pic_base)(void *self);
+
+ /**
+ * Called before abi introduce.
+ */
+ void (*before_abi)(void *self);
+
+ /**
+ * Called, when the graph is being normalized.
+ */
+ void (*prepare_graph)(void *self);
+
+ /**
+ * Backend may provide an own spiller.
+ * This spiller needs to spill all register classes.
+ */
+ void (*spill)(void *self, be_irg_t *birg);
+
+ /**
+ * 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 directly before done is called. This should be the last place
+ * where the irg is modified.
+ */
+ void (*finish)(void *self);
+
+ /**
+ * Called after everything happened. This call should emit the final
+ * assembly code but avoid changing the irg.
+ * 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_cg_call_env(cg, env, func) \
+do { \
+ if((cg)->impl->func) \
+ (cg)->impl->func(cg, env); \
+} 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_finish(cg) _arch_cg_call(cg, finish)
+#define arch_code_generator_done(cg) _arch_cg_call(cg, done)
+#define arch_code_generator_spill(cg, birg) _arch_cg_call_env(cg, birg, spill)
+#define arch_code_generator_has_spiller(cg) ((cg)->impl->spill != NULL)
+#define arch_code_generator_get_pic_base(cg) \
+ ((cg)->impl->get_pic_base != NULL ? (cg)->impl->get_pic_base(cg) : NULL)
+
+/**
+ * Code generator base class.
+ */
+struct arch_code_generator_t {
+ const arch_code_generator_if_t *impl;
+};
+
+/**
+ * Architecture interface.
+ */
+struct arch_isa_if_t {
+ /**
+ * Initialize the isa interface.
+ * @param file_handle the file handle to write the output to
+ * @param main_env the be main environment
+ * @return a new isa instance
+ */
+ arch_env_t *(*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.
+ */
+ unsigned (*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, unsigned 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 call_type The call 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 *call_type, be_abi_call_t *abi);
+
+ /**
+ * 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. There is already a selector given, the
+ * backend is free to modify and/or ignore it.
+ *
+ * @param self The isa object.
+ * @param selector The selector given by options.
+ * @return The list scheduler selector.
+ */
+ const list_sched_selector_t *(*get_list_sched_selector)(const void *self, list_sched_selector_t *selector);
+
+ /**
+ * Get the ILP scheduler to use.
+ * @param self The isa object.
+ * @return The ILP scheduler selector
+ */
+ const ilp_sched_selector_t *(*get_ilp_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);
+
+ /**
+ * A "static" function, returns the frontend settings
+ * needed for this backend.
+ */
+ const backend_params *(*get_params)(void);
+
+ /**
+ * Returns an 2-dim array of execution units, @p irn can be executed on.
+ * The first dimension is the type, the second the allowed units of this
+ * type.
+ * Each dimension is a NULL terminated list.
+ * @param self The isa object.
+ * @param irn The node.
+ * @return An array of allowed execution units.
+ * exec_unit = {
+ * { unit1_of_tp1, ..., unitX1_of_tp1, NULL },
+ * ...,
+ * { unit1_of_tpY, ..., unitXn_of_tpY, NULL },
+ * NULL
+ * };
+ */
+ const be_execution_unit_t ***(*get_allowed_execution_units)(const void *self, const ir_node *irn);
+
+ /**
+ * Return the abstract machine for this isa.
+ * @param self The isa object.
+ */
+ const be_machine_t *(*get_machine)(const void *self);
+
+ /**
+ * Return an ordered list of irgs where code should be generated for.
+ * If NULL is returned, all irg will be taken into account and they will be
+ * generated in an arbitrary order.
+ * @param self The isa object.
+ * @param irgs A flexible array ARR_F of length 0 where the backend can append the desired irgs.
+ * @return A flexible array ARR_F containing all desired irgs in the desired order.
+ */
+ ir_graph **(*get_backend_irg_list)(const void *self, ir_graph ***irgs);
+
+ /**
+ * mark node as rematerialized
+ */
+ void (*mark_remat)(const void *self, ir_node *node);
+
+ /**
+ * parse an assembler constraint part and set flags according to its nature
+ * advances the *c pointer to point to the last parsed character (so if you
+ * parse a single character don't advance c)
+ */
+ asm_constraint_flags_t (*parse_asm_constraint)(const void *self, const char **c);
+
+ /**
+ * returns true if the string is a valid clobbered (register) in this
+ * backend
+ */
+ int (*is_valid_clobber)(const void *self, const char *clobber);
+};
+
+#define arch_env_done(env) ((env)->impl->done(env))
+#define arch_env_get_n_reg_class(env) ((env)->impl->get_n_reg_class(env))
+#define arch_env_get_reg_class(env,i) ((env)->impl->get_reg_class(env, i))
+#define arch_env_get_reg_class_for_mode(env,mode) ((env)->impl->get_reg_class_for_mode((env), (mode)))
+#define arch_env_get_call_abi(env,tp,abi) ((env)->impl->get_call_abi((env), (tp), (abi)))
+#define arch_env_get_code_generator_if(env) ((env)->impl->get_code_generator_if((env)))
+#define arch_env_get_list_sched_selector(env,selector) ((env)->impl->get_list_sched_selector((env), (selector)))
+#define arch_env_get_ilp_sched_selector(env) ((env)->impl->get_ilp_sched_selector(env))
+#define arch_env_get_reg_class_alignment(env,cls) ((env)->impl->get_reg_class_alignment((env), (cls)))
+#define arch_env_get_params(env) ((env)->impl->get_params())
+#define arch_env_get_allowed_execution_units(env,irn) ((env)->impl->get_allowed_execution_units((env), (irn)))
+#define arch_env_get_machine(env) ((env)->impl->get_machine(env))
+#define arch_env_get_backend_irg_list(env,irgs) ((env)->impl->get_backend_irg_list((env), (irgs)))
+#define arch_env_parse_asm_constraint(env,c) ((env)->impl->parse_asm_constraint((env), (c))
+#define arch_env_is_valid_clobber(env,clobber) ((env)->impl->is_valid_clobber((env), (clobber))
+#define arch_env_mark_remat(env,node) \
+ do { if ((env)->impl->mark_remat != NULL) (env)->impl->mark_remat((env), (node)); } while(0)
+
+/**
+ * ISA base class.
+ */
+struct arch_env_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. */
+ int stack_dir; /** -1 for decreasing, 1 for increasing. */
+ int stack_alignment; /** power of 2 stack alignment */
+ const be_main_env_t *main_env; /** the be main environment */
+ int spill_cost; /** cost for a be_Spill node */
+ int reload_cost; /** cost for a be_Reload node */
+};