mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-12-04 00:30:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

bpo-44531: Add _PyType_AllocNoTrack() function (GH-26947)

Browse source 
Add an internal _PyType_AllocNoTrack() function to allocate an object
without tracking it in the GC.

Modify dict_new() to use _PyType_AllocNoTrack(): dict subclasses are
now only tracked once all PyDictObject members are initialized.
Calling _PyObject_GC_UNTRACK() is no longer needed for the dict type.

Similar change in tuple_subtype_new() for tuple subclasses.

Replace tuple_gc_track() with _PyObject_GC_TRACK().
This commit is contained in:
Victor Stinner 2021-07-01 02:30:46 +02:00 • committed by GitHub
parent 1b28187a0e
commit 818628c2da
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
4 changed files with 51 additions and 28 deletions
Download patch file Download diff file Expand all files Collapse all files

30
Objects/dictobject.c
View file

@ -3324,19 +3324,16 @@ static PyNumberMethods dict_as_number = {
static PyObject *
dict_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
PyObject *self;
PyDictObject *d;
assert(type != NULL);
assert(type->tp_alloc != NULL);
// dict subclasses must implement the GC protocol
assert(_PyType_IS_GC(type));
assert(type != NULL && type->tp_alloc != NULL);
self = type->tp_alloc(type, 0);
if (self == NULL)
PyObject *self = type->tp_alloc(type, 0);
if (self == NULL) {
return NULL;
d = (PyDictObject *)self;
/* The object has been implicitly tracked by tp_alloc */
if (type == &PyDict_Type) {
_PyObject_GC_UNTRACK(d);
}
PyDictObject *d = (PyDictObject *)self;
d->ma_used = 0;
d->ma_version_tag = DICT_NEXT_VERSION();
@ -3344,6 +3341,17 @@ dict_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
d->ma_keys = Py_EMPTY_KEYS;
d->ma_values = empty_values;
ASSERT_CONSISTENT(d);
if (type != &PyDict_Type) {
// Don't track if a subclass tp_alloc is PyType_GenericAlloc()
if (!_PyObject_GC_IS_TRACKED(d)) {
_PyObject_GC_TRACK(d);
}
}
else {
// _PyType_AllocNoTrack() does not track the created object
assert(!_PyObject_GC_IS_TRACKED(d));
}
return self;
}
@ -3441,7 +3449,7 @@ PyTypeObject PyDict_Type = {
0, /* tp_descr_set */
0, /* tp_dictoffset */
dict_init, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
_PyType_AllocNoTrack, /* tp_alloc */
dict_new, /* tp_new */
PyObject_GC_Del, /* tp_free */
.tp_vectorcall = dict_vectorcall,