gh-115999: Specialize `STORE_ATTR` in free-threaded builds. (gh-127838)

* Add `_PyDictKeys_StringLookupSplit` which does locking on dict keys and
  use in place of `_PyDictKeys_StringLookup`.

* Change `_PyObject_TryGetInstanceAttribute` to use that function
  in the case of split keys.

* Add `unicodekeys_lookup_split` helper which allows code sharing
  between `_Py_dict_lookup` and `_PyDictKeys_StringLookupSplit`.

* Fix locking for `STORE_ATTR_INSTANCE_VALUE`.  Create
  `_GUARD_TYPE_VERSION_AND_LOCK` uop so that object stays locked and
  `tp_version_tag` cannot change.

* Pass `tp_version_tag` to `specialize_dict_access()`, ensuring
  the version we store on the cache is the correct one (in case of
  it changing during the specalize analysis).

* Split `analyze_descriptor` into `analyze_descriptor_load` and
  `analyze_descriptor_store` since those don't share much logic.
  Add `descriptor_is_class` helper function.

* In `specialize_dict_access`, double check `_PyObject_GetManagedDict()`
  in case we race and dict was materialized before the lock.

* Avoid borrowed references in `_Py_Specialize_StoreAttr()`.

* Use `specialize()` and `unspecialize()` helpers.

* Add unit tests to ensure specializing happens as expected in FT builds.

* Add unit tests to attempt to trigger data races (useful for running under TSAN).

* Add `has_split_table` function to `_testinternalcapi`.

4 files changed, 109 insertions, 103 deletions

diff --git a/Include/internal/pycore_dict.h b/Include/internal/pycore_dict.h
index 6e4a308..7192700 100644
--- a/Include/internal/pycore_dict.h
+++ b/Include/internal/pycore_dict.h
@@ -114,6 +114,7 @@ extern Py_ssize_t _Py_dict_lookup_threadsafe_stackref(PyDictObject *mp, PyObject
 
 extern Py_ssize_t _PyDict_LookupIndex(PyDictObject *, PyObject *);
 extern Py_ssize_t _PyDictKeys_StringLookup(PyDictKeysObject* dictkeys, PyObject *key);
+extern Py_ssize_t _PyDictKeys_StringLookupSplit(PyDictKeysObject* dictkeys, PyObject *key);
 PyAPI_FUNC(PyObject *)_PyDict_LoadGlobal(PyDictObject *, PyDictObject *, PyObject *);
 PyAPI_FUNC(void) _PyDict_LoadGlobalStackRef(PyDictObject *, PyDictObject *, PyObject *, _PyStackRef *);
 
diff --git a/Include/internal/pycore_opcode_metadata.h b/Include/internal/pycore_opcode_metadata.h
index e09fff0..5fb2368 100644
--- a/Include/internal/pycore_opcode_metadata.h
+++ b/Include/internal/pycore_opcode_metadata.h
@@ -2141,7 +2141,7 @@ const struct opcode_metadata _PyOpcode_opcode_metadata[266] = {
     [SET_UPDATE] = { true, INSTR_FMT_IB, HAS_ARG_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG },
     [STORE_ATTR] = { true, INSTR_FMT_IBC000, HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG },
     [STORE_ATTR_INSTANCE_VALUE] = { true, INSTR_FMT_IXC000, HAS_EXIT_FLAG },
-    [STORE_ATTR_SLOT] = { true, INSTR_FMT_IXC000, HAS_EXIT_FLAG },
+    [STORE_ATTR_SLOT] = { true, INSTR_FMT_IXC000, HAS_DEOPT_FLAG | HAS_EXIT_FLAG },
     [STORE_ATTR_WITH_HINT] = { true, INSTR_FMT_IBC000, HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_DEOPT_FLAG | HAS_EXIT_FLAG | HAS_ESCAPES_FLAG },
     [STORE_DEREF] = { true, INSTR_FMT_IB, HAS_ARG_FLAG | HAS_FREE_FLAG | HAS_ESCAPES_FLAG },
     [STORE_FAST] = { true, INSTR_FMT_IB, HAS_ARG_FLAG | HAS_LOCAL_FLAG },
@@ -2340,7 +2340,7 @@ _PyOpcode_macro_expansion[256] = {
     [SET_FUNCTION_ATTRIBUTE] = { .nuops = 1, .uops = { { _SET_FUNCTION_ATTRIBUTE, 0, 0 } } },
     [SET_UPDATE] = { .nuops = 1, .uops = { { _SET_UPDATE, 0, 0 } } },
     [STORE_ATTR] = { .nuops = 1, .uops = { { _STORE_ATTR, 0, 0 } } },
-    [STORE_ATTR_INSTANCE_VALUE] = { .nuops = 3, .uops = { { _GUARD_TYPE_VERSION, 2, 1 }, { _GUARD_DORV_NO_DICT, 0, 0 }, { _STORE_ATTR_INSTANCE_VALUE, 1, 3 } } },
+    [STORE_ATTR_INSTANCE_VALUE] = { .nuops = 3, .uops = { { _GUARD_TYPE_VERSION_AND_LOCK, 2, 1 }, { _GUARD_DORV_NO_DICT, 0, 0 }, { _STORE_ATTR_INSTANCE_VALUE, 1, 3 } } },
     [STORE_ATTR_SLOT] = { .nuops = 2, .uops = { { _GUARD_TYPE_VERSION, 2, 1 }, { _STORE_ATTR_SLOT, 1, 3 } } },
     [STORE_ATTR_WITH_HINT] = { .nuops = 2, .uops = { { _GUARD_TYPE_VERSION, 2, 1 }, { _STORE_ATTR_WITH_HINT, 1, 3 } } },
     [STORE_DEREF] = { .nuops = 1, .uops = { { _STORE_DEREF, 0, 0 } } },
diff --git a/Include/internal/pycore_uop_ids.h b/Include/internal/pycore_uop_ids.h
index 5fc57e4..92515b4 100644
--- a/Include/internal/pycore_uop_ids.h
+++ b/Include/internal/pycore_uop_ids.h
@@ -139,15 +139,16 @@ extern "C" {
 #define _GUARD_TOS_FLOAT 386
 #define _GUARD_TOS_INT 387
 #define _GUARD_TYPE_VERSION 388
+#define _GUARD_TYPE_VERSION_AND_LOCK 389
 #define _IMPORT_FROM IMPORT_FROM
 #define _IMPORT_NAME IMPORT_NAME
-#define _INIT_CALL_BOUND_METHOD_EXACT_ARGS 389
-#define _INIT_CALL_PY_EXACT_ARGS 390
-#define _INIT_CALL_PY_EXACT_ARGS_0 391
-#define _INIT_CALL_PY_EXACT_ARGS_1 392
-#define _INIT_CALL_PY_EXACT_ARGS_2 393
-#define _INIT_CALL_PY_EXACT_ARGS_3 394
-#define _INIT_CALL_PY_EXACT_ARGS_4 395
+#define _INIT_CALL_BOUND_METHOD_EXACT_ARGS 390
+#define _INIT_CALL_PY_EXACT_ARGS 391
+#define _INIT_CALL_PY_EXACT_ARGS_0 392
+#define _INIT_CALL_PY_EXACT_ARGS_1 393
+#define _INIT_CALL_PY_EXACT_ARGS_2 394
+#define _INIT_CALL_PY_EXACT_ARGS_3 395
+#define _INIT_CALL_PY_EXACT_ARGS_4 396
 #define _INSTRUMENTED_CALL_FUNCTION_EX INSTRUMENTED_CALL_FUNCTION_EX
 #define _INSTRUMENTED_CALL_KW INSTRUMENTED_CALL_KW
 #define _INSTRUMENTED_FOR_ITER INSTRUMENTED_FOR_ITER
@@ -160,143 +161,143 @@ extern "C" {
 #define _INSTRUMENTED_POP_JUMP_IF_NONE INSTRUMENTED_POP_JUMP_IF_NONE
 #define _INSTRUMENTED_POP_JUMP_IF_NOT_NONE INSTRUMENTED_POP_JUMP_IF_NOT_NONE
 #define _INSTRUMENTED_POP_JUMP_IF_TRUE INSTRUMENTED_POP_JUMP_IF_TRUE
-#define _INTERNAL_INCREMENT_OPT_COUNTER 396
-#define _IS_NONE 397
+#define _INTERNAL_INCREMENT_OPT_COUNTER 397
+#define _IS_NONE 398
 #define _IS_OP IS_OP
-#define _ITER_CHECK_LIST 398
-#define _ITER_CHECK_RANGE 399
-#define _ITER_CHECK_TUPLE 400
-#define _ITER_JUMP_LIST 401
-#define _ITER_JUMP_RANGE 402
-#define _ITER_JUMP_TUPLE 403
-#define _ITER_NEXT_LIST 404
-#define _ITER_NEXT_RANGE 405
-#define _ITER_NEXT_TUPLE 406
-#define _JUMP_TO_TOP 407
+#define _ITER_CHECK_LIST 399
+#define _ITER_CHECK_RANGE 400
+#define _ITER_CHECK_TUPLE 401
+#define _ITER_JUMP_LIST 402
+#define _ITER_JUMP_RANGE 403
+#define _ITER_JUMP_TUPLE 404
+#define _ITER_NEXT_LIST 405
+#define _ITER_NEXT_RANGE 406
+#define _ITER_NEXT_TUPLE 407
+#define _JUMP_TO_TOP 408
 #define _LIST_APPEND LIST_APPEND
 #define _LIST_EXTEND LIST_EXTEND
-#define _LOAD_ATTR 408
-#define _LOAD_ATTR_CLASS 409
-#define _LOAD_ATTR_CLASS_0 410
-#define _LOAD_ATTR_CLASS_1 411
+#define _LOAD_ATTR 409
+#define _LOAD_ATTR_CLASS 410
+#define _LOAD_ATTR_CLASS_0 411
+#define _LOAD_ATTR_CLASS_1 412
 #define _LOAD_ATTR_GETATTRIBUTE_OVERRIDDEN LOAD_ATTR_GETATTRIBUTE_OVERRIDDEN
-#define _LOAD_ATTR_INSTANCE_VALUE 412
-#define _LOAD_ATTR_INSTANCE_VALUE_0 413
-#define _LOAD_ATTR_INSTANCE_VALUE_1 414
-#define _LOAD_ATTR_METHOD_LAZY_DICT 415
-#define _LOAD_ATTR_METHOD_NO_DICT 416
-#define _LOAD_ATTR_METHOD_WITH_VALUES 417
-#define _LOAD_ATTR_MODULE 418
-#define _LOAD_ATTR_MODULE_FROM_KEYS 419
-#define _LOAD_ATTR_NONDESCRIPTOR_NO_DICT 420
-#define _LOAD_ATTR_NONDESCRIPTOR_WITH_VALUES 421
-#define _LOAD_ATTR_PROPERTY_FRAME 422
-#define _LOAD_ATTR_SLOT 423
-#define _LOAD_ATTR_SLOT_0 424
-#define _LOAD_ATTR_SLOT_1 425
-#define _LOAD_ATTR_WITH_HINT 426
+#define _LOAD_ATTR_INSTANCE_VALUE 413
+#define _LOAD_ATTR_INSTANCE_VALUE_0 414
+#define _LOAD_ATTR_INSTANCE_VALUE_1 415
+#define _LOAD_ATTR_METHOD_LAZY_DICT 416
+#define _LOAD_ATTR_METHOD_NO_DICT 417
+#define _LOAD_ATTR_METHOD_WITH_VALUES 418
+#define _LOAD_ATTR_MODULE 419
+#define _LOAD_ATTR_MODULE_FROM_KEYS 420
+#define _LOAD_ATTR_NONDESCRIPTOR_NO_DICT 421
+#define _LOAD_ATTR_NONDESCRIPTOR_WITH_VALUES 422
+#define _LOAD_ATTR_PROPERTY_FRAME 423
+#define _LOAD_ATTR_SLOT 424
+#define _LOAD_ATTR_SLOT_0 425
+#define _LOAD_ATTR_SLOT_1 426
+#define _LOAD_ATTR_WITH_HINT 427
 #define _LOAD_BUILD_CLASS LOAD_BUILD_CLASS
-#define _LOAD_BYTECODE 427
+#define _LOAD_BYTECODE 428
 #define _LOAD_COMMON_CONSTANT LOAD_COMMON_CONSTANT
 #define _LOAD_CONST LOAD_CONST
 #define _LOAD_CONST_IMMORTAL LOAD_CONST_IMMORTAL
-#define _LOAD_CONST_INLINE 428
-#define _LOAD_CONST_INLINE_BORROW 429
-#define _LOAD_CONST_INLINE_BORROW_WITH_NULL 430
-#define _LOAD_CONST_INLINE_WITH_NULL 431
+#define _LOAD_CONST_INLINE 429
+#define _LOAD_CONST_INLINE_BORROW 430
+#define _LOAD_CONST_INLINE_BORROW_WITH_NULL 431
+#define _LOAD_CONST_INLINE_WITH_NULL 432
 #define _LOAD_DEREF LOAD_DEREF
-#define _LOAD_FAST 432
-#define _LOAD_FAST_0 433
-#define _LOAD_FAST_1 434
-#define _LOAD_FAST_2 435
-#define _LOAD_FAST_3 436
-#define _LOAD_FAST_4 437
-#define _LOAD_FAST_5 438
-#define _LOAD_FAST_6 439
-#define _LOAD_FAST_7 440
+#define _LOAD_FAST 433
+#define _LOAD_FAST_0 434
+#define _LOAD_FAST_1 435
+#define _LOAD_FAST_2 436
+#define _LOAD_FAST_3 437
+#define _LOAD_FAST_4 438
+#define _LOAD_FAST_5 439
+#define _LOAD_FAST_6 440
+#define _LOAD_FAST_7 441
 #define _LOAD_FAST_AND_CLEAR LOAD_FAST_AND_CLEAR
 #define _LOAD_FAST_CHECK LOAD_FAST_CHECK
 #define _LOAD_FAST_LOAD_FAST LOAD_FAST_LOAD_FAST
 #define _LOAD_FROM_DICT_OR_DEREF LOAD_FROM_DICT_OR_DEREF
 #define _LOAD_FROM_DICT_OR_GLOBALS LOAD_FROM_DICT_OR_GLOBALS
-#define _LOAD_GLOBAL 441
-#define _LOAD_GLOBAL_BUILTINS 442
-#define _LOAD_GLOBAL_BUILTINS_FROM_KEYS 443
-#define _LOAD_GLOBAL_MODULE 444
-#define _LOAD_GLOBAL_MODULE_FROM_KEYS 445
+#define _LOAD_GLOBAL 442
+#define _LOAD_GLOBAL_BUILTINS 443
+#define _LOAD_GLOBAL_BUILTINS_FROM_KEYS 444
+#define _LOAD_GLOBAL_MODULE 445
+#define _LOAD_GLOBAL_MODULE_FROM_KEYS 446
 #define _LOAD_LOCALS LOAD_LOCALS
 #define _LOAD_NAME LOAD_NAME
-#define _LOAD_SMALL_INT 446
-#define _LOAD_SMALL_INT_0 447
-#define _LOAD_SMALL_INT_1 448
-#define _LOAD_SMALL_INT_2 449
-#define _LOAD_SMALL_INT_3 450
+#define _LOAD_SMALL_INT 447
+#define _LOAD_SMALL_INT_0 448
+#define _LOAD_SMALL_INT_1 449
+#define _LOAD_SMALL_INT_2 450
+#define _LOAD_SMALL_INT_3 451
 #define _LOAD_SPECIAL LOAD_SPECIAL
 #define _LOAD_SUPER_ATTR_ATTR LOAD_SUPER_ATTR_ATTR
 #define _LOAD_SUPER_ATTR_METHOD LOAD_SUPER_ATTR_METHOD
-#define _MAKE_CALLARGS_A_TUPLE 451
+#define _MAKE_CALLARGS_A_TUPLE 452
 #define _MAKE_CELL MAKE_CELL
 #define _MAKE_FUNCTION MAKE_FUNCTION
-#define _MAKE_WARM 452
+#define _MAKE_WARM 453
 #define _MAP_ADD MAP_ADD
 #define _MATCH_CLASS MATCH_CLASS
 #define _MATCH_KEYS MATCH_KEYS
 #define _MATCH_MAPPING MATCH_MAPPING
 #define _MATCH_SEQUENCE MATCH_SEQUENCE
-#define _MAYBE_EXPAND_METHOD 453
-#define _MAYBE_EXPAND_METHOD_KW 454
-#define _MONITOR_CALL 455
-#define _MONITOR_JUMP_BACKWARD 456
-#define _MONITOR_RESUME 457
+#define _MAYBE_EXPAND_METHOD 454
+#define _MAYBE_EXPAND_METHOD_KW 455
+#define _MONITOR_CALL 456
+#define _MONITOR_JUMP_BACKWARD 457
+#define _MONITOR_RESUME 458
 #define _NOP NOP
 #define _POP_EXCEPT POP_EXCEPT
-#define _POP_JUMP_IF_FALSE 458
-#define _POP_JUMP_IF_TRUE 459
+#define _POP_JUMP_IF_FALSE 459
+#define _POP_JUMP_IF_TRUE 460
 #define _POP_TOP POP_TOP
-#define _POP_TOP_LOAD_CONST_INLINE_BORROW 460
+#define _POP_TOP_LOAD_CONST_INLINE_BORROW 461
 #define _PUSH_EXC_INFO PUSH_EXC_INFO
-#define _PUSH_FRAME 461
+#define _PUSH_FRAME 462
 #define _PUSH_NULL PUSH_NULL
-#define _PY_FRAME_GENERAL 462
-#define _PY_FRAME_KW 463
-#define _QUICKEN_RESUME 464
-#define _REPLACE_WITH_TRUE 465
+#define _PY_FRAME_GENERAL 463
+#define _PY_FRAME_KW 464
+#define _QUICKEN_RESUME 465
+#define _REPLACE_WITH_TRUE 466
 #define _RESUME_CHECK RESUME_CHECK
 #define _RETURN_GENERATOR RETURN_GENERATOR
 #define _RETURN_VALUE RETURN_VALUE
-#define _SAVE_RETURN_OFFSET 466
-#define _SEND 467
-#define _SEND_GEN_FRAME 468
+#define _SAVE_RETURN_OFFSET 467
+#define _SEND 468
+#define _SEND_GEN_FRAME 469
 #define _SETUP_ANNOTATIONS SETUP_ANNOTATIONS
 #define _SET_ADD SET_ADD
 #define _SET_FUNCTION_ATTRIBUTE SET_FUNCTION_ATTRIBUTE
 #define _SET_UPDATE SET_UPDATE
-#define _START_EXECUTOR 469
-#define _STORE_ATTR 470
-#define _STORE_ATTR_INSTANCE_VALUE 471
-#define _STORE_ATTR_SLOT 472
-#define _STORE_ATTR_WITH_HINT 473
+#define _START_EXECUTOR 470
+#define _STORE_ATTR 471
+#define _STORE_ATTR_INSTANCE_VALUE 472
+#define _STORE_ATTR_SLOT 473
+#define _STORE_ATTR_WITH_HINT 474
 #define _STORE_DEREF STORE_DEREF
-#define _STORE_FAST 474
-#define _STORE_FAST_0 475
-#define _STORE_FAST_1 476
-#define _STORE_FAST_2 477
-#define _STORE_FAST_3 478
-#define _STORE_FAST_4 479
-#define _STORE_FAST_5 480
-#define _STORE_FAST_6 481
-#define _STORE_FAST_7 482
+#define _STORE_FAST 475
+#define _STORE_FAST_0 476
+#define _STORE_FAST_1 477
+#define _STORE_FAST_2 478
+#define _STORE_FAST_3 479
+#define _STORE_FAST_4 480
+#define _STORE_FAST_5 481
+#define _STORE_FAST_6 482
+#define _STORE_FAST_7 483
 #define _STORE_FAST_LOAD_FAST STORE_FAST_LOAD_FAST
 #define _STORE_FAST_STORE_FAST STORE_FAST_STORE_FAST
 #define _STORE_GLOBAL STORE_GLOBAL
 #define _STORE_NAME STORE_NAME
-#define _STORE_SLICE 483
-#define _STORE_SUBSCR 484
+#define _STORE_SLICE 484
+#define _STORE_SUBSCR 485
 #define _STORE_SUBSCR_DICT STORE_SUBSCR_DICT
 #define _STORE_SUBSCR_LIST_INT STORE_SUBSCR_LIST_INT
 #define _SWAP SWAP
-#define _TIER2_RESUME_CHECK 485
-#define _TO_BOOL 486
+#define _TIER2_RESUME_CHECK 486
+#define _TO_BOOL 487
 #define _TO_BOOL_BOOL TO_BOOL_BOOL
 #define _TO_BOOL_INT TO_BOOL_INT
 #define _TO_BOOL_LIST TO_BOOL_LIST
@@ -306,13 +307,13 @@ extern "C" {
 #define _UNARY_NEGATIVE UNARY_NEGATIVE
 #define _UNARY_NOT UNARY_NOT
 #define _UNPACK_EX UNPACK_EX
-#define _UNPACK_SEQUENCE 487
+#define _UNPACK_SEQUENCE 488
 #define _UNPACK_SEQUENCE_LIST UNPACK_SEQUENCE_LIST
 #define _UNPACK_SEQUENCE_TUPLE UNPACK_SEQUENCE_TUPLE
 #define _UNPACK_SEQUENCE_TWO_TUPLE UNPACK_SEQUENCE_TWO_TUPLE
 #define _WITH_EXCEPT_START WITH_EXCEPT_START
 #define _YIELD_VALUE YIELD_VALUE
-#define MAX_UOP_ID 487
+#define MAX_UOP_ID 488
 
 #ifdef __cplusplus
 }
diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
index eadfda4..e71194b 100644
--- a/Include/internal/pycore_uop_metadata.h
+++ b/Include/internal/pycore_uop_metadata.h
@@ -148,6 +148,7 @@ const uint16_t _PyUop_Flags[MAX_UOP_ID+1] = {
     [_LOAD_SUPER_ATTR_METHOD] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_DEOPT_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
     [_LOAD_ATTR] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
     [_GUARD_TYPE_VERSION] = HAS_EXIT_FLAG,
+    [_GUARD_TYPE_VERSION_AND_LOCK] = HAS_EXIT_FLAG,
     [_CHECK_MANAGED_OBJECT_HAS_VALUES] = HAS_DEOPT_FLAG,
     [_LOAD_ATTR_INSTANCE_VALUE_0] = HAS_DEOPT_FLAG,
     [_LOAD_ATTR_INSTANCE_VALUE_1] = HAS_DEOPT_FLAG,
@@ -167,7 +168,7 @@ const uint16_t _PyUop_Flags[MAX_UOP_ID+1] = {
     [_GUARD_DORV_NO_DICT] = HAS_EXIT_FLAG,
     [_STORE_ATTR_INSTANCE_VALUE] = 0,
     [_STORE_ATTR_WITH_HINT] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_DEOPT_FLAG | HAS_ESCAPES_FLAG,
-    [_STORE_ATTR_SLOT] = 0,
+    [_STORE_ATTR_SLOT] = HAS_DEOPT_FLAG,
     [_COMPARE_OP] = HAS_ARG_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
     [_COMPARE_OP_FLOAT] = HAS_ARG_FLAG,
     [_COMPARE_OP_INT] = HAS_ARG_FLAG | HAS_DEOPT_FLAG,
@@ -428,6 +429,7 @@ const char *const _PyOpcode_uop_name[MAX_UOP_ID+1] = {
     [_GUARD_TOS_FLOAT] = "_GUARD_TOS_FLOAT",
     [_GUARD_TOS_INT] = "_GUARD_TOS_INT",
     [_GUARD_TYPE_VERSION] = "_GUARD_TYPE_VERSION",
+    [_GUARD_TYPE_VERSION_AND_LOCK] = "_GUARD_TYPE_VERSION_AND_LOCK",
     [_IMPORT_FROM] = "_IMPORT_FROM",
     [_IMPORT_NAME] = "_IMPORT_NAME",
     [_INIT_CALL_BOUND_METHOD_EXACT_ARGS] = "_INIT_CALL_BOUND_METHOD_EXACT_ARGS",
@@ -839,6 +841,8 @@ int _PyUop_num_popped(int opcode, int oparg)
             return 1;
         case _GUARD_TYPE_VERSION:
             return 0;
+        case _GUARD_TYPE_VERSION_AND_LOCK:
+            return 0;
         case _CHECK_MANAGED_OBJECT_HAS_VALUES:
             return 0;
         case _LOAD_ATTR_INSTANCE_VALUE_0: