is_subclass_of     64 Zend/zend_builtin_functions.c static ZEND_FUNCTION(is_subclass_of);
is_subclass_of    276 Zend/zend_builtin_functions.c 	ZEND_FE(is_subclass_of,		arginfo_is_subclass_of)
is_subclass_of    890 Zend/zend_builtin_functions.c ZEND_FUNCTION(is_subclass_of)