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bpo-42161: Micro-optimize _collections._count_elements()#23008

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Merged
vstinner merged 1 commit into from
Oct 27, 2020
Merged

bpo-42161: Micro-optimize _collections._count_elements() #23008

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9 changes: 5 additions & 4 deletions Modules/_collectionsmodule.c
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Original file line numberDiff line numberDiff line change
Expand Up@@ -2278,6 +2278,7 @@ _collections__count_elements_impl(PyObject *module, PyObject *mapping,
PyObject *dict_get;
PyObject *mapping_setitem;
PyObject *dict_setitem;
PyObject *one = _PyLong_GetOne(); // borrowed reference

it = PyObject_GetIter(iterable);
if (it == NULL)
Expand DownExpand Up@@ -2324,10 +2325,10 @@ _collections__count_elements_impl(PyObject *module, PyObject *mapping,
if (oldval == NULL){
if (PyErr_Occurred())
goto done;
if (_PyDict_SetItem_KnownHash(mapping, key, _PyLong_GetOne(), hash) < 0)
if (_PyDict_SetItem_KnownHash(mapping, key, one, hash) < 0)
goto done;
} else{
newval = PyNumber_Add(oldval, _PyLong_GetOne());
newval = PyNumber_Add(oldval, one);
if (newval == NULL)
goto done;
if (_PyDict_SetItem_KnownHash(mapping, key, newval, hash) < 0)
Expand All@@ -2336,13 +2337,13 @@ _collections__count_elements_impl(PyObject *module, PyObject *mapping,
}
Py_DECREF(key);
}
} else{
}
else{
bound_get = _PyObject_GetAttrId(mapping, &PyId_get);
if (bound_get == NULL)
goto done;

PyObject *zero = _PyLong_GetZero(); // borrowed reference
PyObject *one = _PyLong_GetOne(); // borrowed reference
while (1){
key = PyIter_Next(it);
if (key == NULL)
Expand Down