protocol_list_t * baseProtocols;
const class_ro_t *ro() const {...}
const method_array_t methods() const {...}
cache_t cache;
class_ro_t
class_rw_t
Class superclass;
method_list_t
objc_object
const char *types;
property_list_t *baseProperties;
MethodListIMP imp;
Class _Nonnull isa;
const property_array_t properties() const {...}
objc_class
SEL name;
const ivar_list_t * ivars;
method_t
……
class_rw_t *data() const { return bits.data();}
method_list_t
class_data_bits_t bits;
explicit_atomic<const char *> name;
method_array_t
const protocol_array_t protocols() const {...}
void *baseMethodList;
