Assert we don't get -1 from hashing exact unicode, lock in _PyObject_…

…StoreInstanceAttribute

Objects/dictobject.c

@@ -1597,7 +1597,7 @@ insertion_resize(PyInterpreterState *interp, PyDictObject *mp, int unicode)
 }
 
 static Py_ssize_t
-insert_into_splitdictkeys_locked(PyDictKeysObject *keys, PyObject *name)
+insert_into_splitdictkeys(PyDictKeysObject *keys, PyObject *name)
 {
     assert(PyUnicode_CheckExact(name));
     ASSERT_KEYS_LOCKED(keys);
@@ -1629,15 +1629,6 @@ insert_into_splitdictkeys_locked(PyDictKeysObject *keys, PyObject *name)
     return ix;
 }
 
-static Py_ssize_t
-insert_into_splitdictkeys(PyDictKeysObject *keys, PyObject *name)
-{
-    LOCK_KEYS(keys);
-    Py_ssize_t ix = insert_into_splitdictkeys_locked(keys, name);
-    UNLOCK_KEYS(keys);
-    return ix;
-}
-
 static inline int
 insert_combined_dict(PyInterpreterState *interp, PyDictObject *mp,
                      Py_hash_t hash, PyObject *key, PyObject *value)
@@ -6705,17 +6696,16 @@ _PyObject_StoreInstanceAttribute(PyObject *obj, PyDictValues *values,
         Py_hash_t hash = unicode_get_hash(name);
         if (hash == -1) {
             hash = PyUnicode_Type.tp_hash(name);
-            if (hash == -1) {
-                PyErr_Clear();
-                return DKIX_EMPTY;
-            }
+            assert(hash != -1);
         }
 
         // Try a thread-safe lookup to see if the index is already allocated
         ix = unicodekeys_lookup_unicode_threadsafe(keys, name, hash);
         if (ix == DKIX_EMPTY) {
-            // Fall back to a version that will lock and maybe insert
+            // Lock keys and do insert
+            LOCK_KEYS(keys);
             ix = insert_into_splitdictkeys(keys, name);
+            UNLOCK_KEYS(keys);
         }
 #else
         ix = insert_into_splitdictkeys(keys, name);