gh-140009: Optimize dict object by replacing PyTuple_Pack with PyTuple_FromArray

Author: rashes2006

Misc/NEWS.d/next/Core_and_Builtins/2026-02-06-03-40-59.gh-issue-140009.a1b2c3.rst

@@ -0,0 +1 @@
+Improve performance of dict object by replacing PyTuple_Pack with PyTuple_FromArray for small tuples.

Objects/dictobject.c

@@ -5083,7 +5083,8 @@ dictiter_new(PyDictObject *dict, PyTypeObject *itertype)
     }
     if (itertype == &PyDictIterItem_Type ||
         itertype == &PyDictRevIterItem_Type) {
-        di->di_result = PyTuple_Pack(2, Py_None, Py_None);
+        PyObject *items[] = {Py_None, Py_None};
+        di->di_result = PyTuple_FromArray(items, 2);
         if (di->di_result == NULL) {
             Py_DECREF(di);
             return NULL;
@@ -6284,7 +6285,8 @@ dictitems_xor_lock_held(PyObject *d1, PyObject *d2)
             }
         }
         else {
-            PyObject *pair = PyTuple_Pack(2, key, val2);
+            PyObject *items[] = {key, val2};
+            PyObject *pair = PyTuple_FromArray(items, 2);
             if (pair == NULL) {
                 goto error;
             }