+/**
+ * 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)
+