@@ -4930,7 +4930,7 @@ dictiter_iternext_threadsafe(PyDictObject *d, PyObject *self,
49304930
49314931ensure_shared_on_read (d );
49324932
4933- Py_ssize_t start_pos = i = _Py_atomic_load_ssize_relaxed (& di -> di_pos );
4933+ i = _Py_atomic_load_ssize_relaxed (& di -> di_pos );
49344934k = _Py_atomic_load_ptr_relaxed (& d -> ma_keys );
49354935assert (i >=0 );
49364936if (_PyDict_HasSplitTable (d )) {
@@ -4990,20 +4990,13 @@ dictiter_iternext_threadsafe(PyDictObject *d, PyObject *self,
49904990 }
49914991 }
49924992// We found an element (key), but did not expect it
4993- if (_Py_atomic_load_ssize_relaxed (& di -> len )== 0 ) {
4993+ Py_ssize_t len ;
4994+ if ((len = _Py_atomic_load_ssize_relaxed (& di -> len ))== 0 ) {
49944995 gotoconcurrent_modification ;
49954996 }
4996- if (!_Py_atomic_compare_exchange_ssize (& di -> di_pos ,& start_pos ,i + 1 )) {
4997- // We lost a race with someone else iterating...
4998- if (out_key != NULL ) {
4999- Py_DECREF (* out_key );
5000- }
5001- if (out_value != NULL ) {
5002- Py_DECREF (* out_value );
5003- }
5004- gototry_locked ;
5005- }
5006- _Py_atomic_add_ssize (& di -> len ,-1 );
4997+
4998+ _Py_atomic_store_ssize_relaxed (& di -> di_pos ,i + 1 );
4999+ _Py_atomic_store_ssize_relaxed (& di -> len ,len - 1 );
50075000return 1 ;
50085001
50095002concurrent_modification :
@@ -5029,22 +5022,16 @@ static bool
50295022acquire_iter_result (PyObject * result )
50305023{
50315024#ifdef Py_GIL_DISABLED
5032- if (Py_REFCNT (result )== 1 ) {
5033- Py_INCREF (result );
5034- if (Py_REFCNT (result )== 2 ) {
5035- return true;
5036- }
5037- Py_DECREF (result );
5038- return false;
5039- }
5040- return false;
5025+ if (_Py_IsOwnedByCurrentThread (result )&&
5026+ result -> ob_ref_local == 1 &&
5027+ _Py_atomic_load_ssize_relaxed (& result -> ob_ref_shared )== 0 ) {
50415028#else
50425029if (Py_REFCNT (result )== 1 ) {
5030+ #endif
50435031Py_INCREF (result );
50445032return true;
50455033 }
50465034return false;
5047- #endif
50485035}
50495036
50505037static PyObject *