Remove list optimizations to minimize PR

python · Fidget-Spinner · Jun 17, 2025 · May 23, 2025 · May 23, 2025 · May 23, 2025
commit a42b43483e98039402259b6547d7fd41c76c2c7b
diff --git a/Include/internal/pycore_uop_ids.h b/Include/internal/pycore_uop_ids.h
diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
diff --git a/Lib/test/test_capi/test_opt.py b/Lib/test/test_capi/test_opt.py
@@ -1707,10 +1707,10 @@ def f(n):
         self.assertIsNotNone(ex)
         uops = get_opnames(ex)
         self.assertEqual(uops.count("_GUARD_NOS_LIST"), 0)
-        self.assertEqual(uops.count("_STORE_SUBSCR_LIST_INT__NO_DECREF_INPUTS"), 1)
+        self.assertEqual(uops.count("_STORE_SUBSCR_LIST_INT"), 1)
         self.assertEqual(uops.count("_GUARD_TOS_LIST"), 0)
         self.assertEqual(uops.count("_UNPACK_SEQUENCE_LIST"), 1)
-        self.assertEqual(uops.count("_BINARY_OP_SUBSCR_LIST_INT__NO_DECREF_INPUTS"), 1)
+        self.assertEqual(uops.count("_BINARY_OP_SUBSCR_LIST_INT"), 1)
         self.assertEqual(uops.count("_TO_BOOL_LIST"), 1)
 
     def test_remove_guard_for_known_type_set(self):

@@ -907,32 +907,6 @@ dummy_func(
             DECREF_INPUTS();
         }
 
-        op(_BINARY_OP_SUBSCR_LIST_INT__NO_DECREF_INPUTS, (list_st, sub_st -- res)) {
-            PyObject *sub = PyStackRef_AsPyObjectBorrow(sub_st);
-            PyObject *list = PyStackRef_AsPyObjectBorrow(list_st);
-
-            assert(PyLong_CheckExact(sub));
-            assert(PyList_CheckExact(list));
-
-            // Deopt unless 0 <= sub < PyList_Size(list)
-            DEOPT_IF(!_PyLong_IsNonNegativeCompact((PyLongObject *)sub));
-            Py_ssize_t index = ((PyLongObject*)sub)->long_value.ob_digit[0];
-#ifdef Py_GIL_DISABLED
-            PyObject *res_o = _PyList_GetItemRef((PyListObject*)list, index);
-                DEOPT_IF(res_o == NULL);
-                STAT_INC(BINARY_OP, hit);
-                res = PyStackRef_FromPyObjectSteal(res_o);
-#else
-            DEOPT_IF(index >= PyList_GET_SIZE(list));
-            STAT_INC(BINARY_OP, hit);
-            PyObject *res_o = PyList_GET_ITEM(list, index);
-            assert(res_o != NULL);
-            res = PyStackRef_FromPyObjectNew(res_o);
-#endif
-            STAT_INC(BINARY_OP, hit);
-            INPUTS_DEAD();
-        }
-
         macro(BINARY_OP_SUBSCR_LIST_SLICE) =
             _GUARD_TOS_SLICE + _GUARD_NOS_LIST + unused/5 + _BINARY_OP_SUBSCR_LIST_SLICE;
 
@@ -1135,34 +1109,6 @@ dummy_func(
             Py_DECREF(old_value);
         }
 
-        op(_STORE_SUBSCR_LIST_INT__NO_DECREF_INPUTS, (value, list_st, sub_st -- )) {
-            PyObject *sub = PyStackRef_AsPyObjectBorrow(sub_st);
-            PyObject *list = PyStackRef_AsPyObjectBorrow(list_st);
-
-            assert(PyLong_CheckExact(sub));
-            assert(PyList_CheckExact(list));
-
-            // Ensure nonnegative, zero-or-one-digit ints.
-            DEOPT_IF(!_PyLong_IsNonNegativeCompact((PyLongObject *)sub));
-            Py_ssize_t index = ((PyLongObject*)sub)->long_value.ob_digit[0];
-            DEOPT_IF(!LOCK_OBJECT(list));
-            // Ensure index < len(list)
-            if (index >= PyList_GET_SIZE(list)) {
-                UNLOCK_OBJECT(list);
-                DEOPT_IF(true);
-            }
-            STAT_INC(STORE_SUBSCR, hit);
-
-            PyObject *old_value = PyList_GET_ITEM(list, index);
-            FT_ATOMIC_STORE_PTR_RELEASE(_PyList_ITEMS(list)[index],
-                                        PyStackRef_AsPyObjectSteal(value));
-            assert(old_value != NULL);
-            UNLOCK_OBJECT(list);  // unlock before decrefs!
-            DEAD(sub_st);
-            DEAD(list_st);
-            Py_DECREF(old_value);
-        }
-
         macro(STORE_SUBSCR_DICT) =
             _GUARD_NOS_DICT + unused/1 + _STORE_SUBSCR_DICT;
 

diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
@@ -448,8 +448,6 @@ const uint16_t op_without_decref_inputs[MAX_UOP_ID + 1] = {
     [_BINARY_OP_MULTIPLY_FLOAT] = _BINARY_OP_MULTIPLY_FLOAT__NO_DECREF_INPUTS,
     [_BINARY_OP_ADD_FLOAT] = _BINARY_OP_ADD_FLOAT__NO_DECREF_INPUTS,
     [_BINARY_OP_SUBTRACT_FLOAT] = _BINARY_OP_SUBTRACT_FLOAT__NO_DECREF_INPUTS,
-    [_STORE_SUBSCR_LIST_INT] = _STORE_SUBSCR_LIST_INT__NO_DECREF_INPUTS,
-    [_BINARY_OP_SUBSCR_LIST_INT] = _BINARY_OP_SUBSCR_LIST_INT__NO_DECREF_INPUTS,
 };
 
 /* 1 for success, 0 for not ready, cannot error at the moment. */

@@ -104,15 +104,6 @@ dummy_func(void) {
         GETLOCAL(oparg) = value;
     }
 
-    op(_STORE_SUBSCR_LIST_INT, (value, list_st, sub_st -- )) {
-        // Can't move this to the optimizer generator for now, as it requires list_st and sub_st
-        // to be borrowed, but not value.
-        // Alternatively, we could just stricten it and require all to be borrowed.
-        if (sym_is_skip_refcount(ctx, list_st) && sym_is_skip_refcount(ctx, sub_st)) {
-            REPLACE_OP(this_instr, op_without_decref_inputs[opcode], oparg, 0);
-        }
-    }
-
     op(_PUSH_NULL, (-- res)) {
         res = sym_new_null(ctx);
     }
@@ -403,14 +394,6 @@ dummy_func(void) {
         ctx->done = true;
     }
 
-    op(_BINARY_OP_SUBSCR_LIST_INT, (list_st, sub_st -- res)) {
-        // TODO (gh-134584): Move this to the optimizer generator.
-        if (sym_is_skip_refcount(ctx, list_st) && sym_is_skip_refcount(ctx, sub_st)) {
-            REPLACE_OP(this_instr, op_without_decref_inputs[opcode], oparg, 0);
-        }
-        res = sym_new_not_null(ctx);
-    }
-
     op(_BINARY_OP_SUBSCR_STR_INT, (str_st, sub_st -- res)) {
         res = sym_new_type(ctx, &PyUnicode_Type);
     }

diff --git a/Python/optimizer_cases.c.h b/Python/optimizer_cases.c.h