diff --git a/Include/internal/pycore_typeobject.h b/Include/internal/pycore_typeobject.h index c207ce615c6..4d705740a9a 100644 --- a/Include/internal/pycore_typeobject.h +++ b/Include/internal/pycore_typeobject.h @@ -74,6 +74,10 @@ extern static_builtin_state * _PyStaticType_GetState(PyTypeObject *); extern void _PyStaticType_ClearWeakRefs(PyTypeObject *type); extern void _PyStaticType_Dealloc(PyTypeObject *type); +PyObject * +_Py_type_getattro_impl(PyTypeObject *type, PyObject *name, int *suppress_missing_attribute); +PyObject * +_Py_type_getattro(PyTypeObject *type, PyObject *name); PyObject *_Py_slot_tp_getattro(PyObject *self, PyObject *name); PyObject *_Py_slot_tp_getattr_hook(PyObject *self, PyObject *name); diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-12-04-00-38-33.gh-issue-92216.CJXuWB.rst b/Misc/NEWS.d/next/Core and Builtins/2022-12-04-00-38-33.gh-issue-92216.CJXuWB.rst new file mode 100644 index 00000000000..f7ef52d97c2 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2022-12-04-00-38-33.gh-issue-92216.CJXuWB.rst @@ -0,0 +1 @@ +Improve the performance of :func:`hasattr` for type objects with a missing attribute. diff --git a/Objects/object.c b/Objects/object.c index 028b0edc911..fae508cae3d 100644 --- a/Objects/object.c +++ b/Objects/object.c @@ -939,7 +939,15 @@ _PyObject_LookupAttr(PyObject *v, PyObject *name, PyObject **result) } return 0; } - if (tp->tp_getattro != NULL) { + if (tp->tp_getattro == (getattrofunc)_Py_type_getattro) { + int supress_missing_attribute_exception = 0; + *result = _Py_type_getattro_impl((PyTypeObject*)v, name, &supress_missing_attribute_exception); + if (supress_missing_attribute_exception) { + // return 0 without having to clear the exception + return 0; + } + } + else if (tp->tp_getattro != NULL) { *result = (*tp->tp_getattro)(v, name); } else if (tp->tp_getattr != NULL) { diff --git a/Objects/typeobject.c b/Objects/typeobject.c index a96f993e99d..16b1a3035d5 100644 --- a/Objects/typeobject.c +++ b/Objects/typeobject.c @@ -4219,9 +4219,19 @@ _PyType_LookupId(PyTypeObject *type, _Py_Identifier *name) } /* This is similar to PyObject_GenericGetAttr(), - but uses _PyType_Lookup() instead of just looking in type->tp_dict. */ -static PyObject * -type_getattro(PyTypeObject *type, PyObject *name) + but uses _PyType_Lookup() instead of just looking in type->tp_dict. + + The argument suppress_missing_attribute is used to provide a + fast path for hasattr. The possible values are: + + * NULL: do not suppress the exception + * Non-zero pointer: suppress the PyExc_AttributeError and + set *suppress_missing_attribute to 1 to signal we are returning NULL while + having suppressed the exception (other exceptions are not suppressed) + + */ +PyObject * +_Py_type_getattro_impl(PyTypeObject *type, PyObject *name, int * suppress_missing_attribute) { PyTypeObject *metatype = Py_TYPE(type); PyObject *meta_attribute, *attribute; @@ -4301,12 +4311,25 @@ type_getattro(PyTypeObject *type, PyObject *name) } /* Give up */ - PyErr_Format(PyExc_AttributeError, - "type object '%.50s' has no attribute '%U'", - type->tp_name, name); + if (suppress_missing_attribute == NULL) { + PyErr_Format(PyExc_AttributeError, + "type object '%.50s' has no attribute '%U'", + type->tp_name, name); + } else { + // signal the caller we have not set an PyExc_AttributeError and gave up + *suppress_missing_attribute = 1; + } return NULL; } +/* This is similar to PyObject_GenericGetAttr(), + but uses _PyType_Lookup() instead of just looking in type->tp_dict. */ +PyObject * +_Py_type_getattro(PyTypeObject *type, PyObject *name) +{ + return _Py_type_getattro_impl(type, name, NULL); +} + static int type_setattro(PyTypeObject *type, PyObject *name, PyObject *value) { @@ -4798,7 +4821,7 @@ PyTypeObject PyType_Type = { 0, /* tp_hash */ (ternaryfunc)type_call, /* tp_call */ 0, /* tp_str */ - (getattrofunc)type_getattro, /* tp_getattro */ + (getattrofunc)_Py_type_getattro, /* tp_getattro */ (setattrofunc)type_setattro, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |