diff options
| -rw-r--r-- | Misc/NEWS | 3 | ||||
| -rw-r--r-- | Objects/abstract.c | 15 |
2 files changed, 18 insertions, 0 deletions
@@ -10,6 +10,9 @@ Release date: TBA Core and Builtins ----------------- +- Issue #22540: speed up `PyObject_IsInstance` and `PyObject_IsSubclass` in the + common case that the second argument has metaclass `type`. + - Issue #18711: Add a new `PyErr_FormatV` function, similar to `PyErr_Format` but accepting a `va_list` argument. diff --git a/Objects/abstract.c b/Objects/abstract.c index ec59972..177c34a 100644 --- a/Objects/abstract.c +++ b/Objects/abstract.c @@ -2538,6 +2538,11 @@ PyObject_IsInstance(PyObject *inst, PyObject *cls) if (Py_TYPE(inst) == (PyTypeObject *)cls) return 1; + /* We know what type's __instancecheck__ does. */ + if (PyType_CheckExact(cls)) { + return recursive_isinstance(inst, cls); + } + if (PyTuple_Check(cls)) { Py_ssize_t i; Py_ssize_t n; @@ -2576,6 +2581,7 @@ PyObject_IsInstance(PyObject *inst, PyObject *cls) } else if (PyErr_Occurred()) return -1; + /* Probably never reached anymore. */ return recursive_isinstance(inst, cls); } @@ -2603,6 +2609,14 @@ PyObject_IsSubclass(PyObject *derived, PyObject *cls) _Py_IDENTIFIER(__subclasscheck__); PyObject *checker; + /* We know what type's __subclasscheck__ does. */ + if (PyType_CheckExact(cls)) { + /* Quick test for an exact match */ + if (derived == cls) + return 1; + return recursive_issubclass(derived, cls); + } + if (PyTuple_Check(cls)) { Py_ssize_t i; Py_ssize_t n; @@ -2641,6 +2655,7 @@ PyObject_IsSubclass(PyObject *derived, PyObject *cls) } else if (PyErr_Occurred()) return -1; + /* Probably never reached anymore. */ return recursive_issubclass(derived, cls); } |