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gh-115999: Enable specialization of CALL instructions in free-threaded builds (#127123)

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The CALL family of instructions were mostly thread-safe already and only required a small number of changes, which are documented below.

A few changes were needed to make CALL_ALLOC_AND_ENTER_INIT thread-safe:

Added _PyType_LookupRefAndVersion, which returns the type version corresponding to the returned ref.

Added _PyType_CacheInitForSpecialization, which takes an init method and the corresponding type version and only populates the specialization cache if the current type version matches the supplied version. This prevents potentially caching a stale value in free-threaded builds if we race with an update to __init__.

Only cache __init__ functions that are deferred in free-threaded builds. This ensures that the reference to __init__ that is stored in the specialization cache is valid if the type version guard in _CHECK_AND_ALLOCATE_OBJECT passes.
Fix a bug in _CREATE_INIT_FRAME where the frame is pushed to the stack on failure.

A few other miscellaneous changes were also needed:

Use {LOCK,UNLOCK}_OBJECT in LIST_APPEND. This ensures that the list's per-object lock is held while we are appending to it.

Add missing co_tlbc for _Py_InitCleanup.

Stop/start the world around setting the eval frame hook. This allows us to read interp->eval_frame non-atomically and preserves the behavior of _CHECK_PEP_523 documented below.
This commit is contained in:
mpage 2024-12-03 11:20:20 -08:00 • committed by GitHub
parent fc5a0dc224
commit dabcecfd6d
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
11 changed files with 220 additions and 92 deletions
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16
Python/bytecodes.c
View file

@ -3329,7 +3329,7 @@ dummy_func(
};
specializing op(_SPECIALIZE_CALL, (counter/1, callable[1], self_or_null[1], args[oparg] -- callable[1], self_or_null[1], args[oparg])) {
#if ENABLE_SPECIALIZATION
#if ENABLE_SPECIALIZATION_FT
if (ADAPTIVE_COUNTER_TRIGGERS(counter)) {
next_instr = this_instr;
_Py_Specialize_Call(callable[0], next_instr, oparg + !PyStackRef_IsNull(self_or_null[0]));
@ -3337,7 +3337,7 @@ dummy_func(
}
OPCODE_DEFERRED_INC(CALL);
ADVANCE_ADAPTIVE_COUNTER(this_instr[1].counter);
#endif /* ENABLE_SPECIALIZATION */
#endif /* ENABLE_SPECIALIZATION_FT */
}
op(_MAYBE_EXPAND_METHOD, (callable[1], self_or_null[1], args[oparg] -- func[1], maybe_self[1], args[oparg])) {
@ -3722,10 +3722,10 @@ dummy_func(
DEOPT_IF(!PyStackRef_IsNull(null[0]));
DEOPT_IF(!PyType_Check(callable_o));
PyTypeObject *tp = (PyTypeObject *)callable_o;
DEOPT_IF(tp->tp_version_tag != type_version);
DEOPT_IF(FT_ATOMIC_LOAD_UINT32_RELAXED(tp->tp_version_tag) != type_version);
assert(tp->tp_flags & Py_TPFLAGS_INLINE_VALUES);
PyHeapTypeObject *cls = (PyHeapTypeObject *)callable_o;
PyFunctionObject *init_func = (PyFunctionObject *)cls->_spec_cache.init;
PyFunctionObject *init_func = (PyFunctionObject *)FT_ATOMIC_LOAD_PTR_ACQUIRE(cls->_spec_cache.init);
PyCodeObject *code = (PyCodeObject *)init_func->func_code;
DEOPT_IF(!_PyThreadState_HasStackSpace(tstate, code->co_framesize + _Py_InitCleanup.co_framesize));
STAT_INC(CALL, hit);
@ -3743,17 +3743,19 @@ dummy_func(
_PyInterpreterFrame *shim = _PyFrame_PushTrampolineUnchecked(
tstate, (PyCodeObject *)&_Py_InitCleanup, 1, frame);
assert(_PyFrame_GetBytecode(shim)[0].op.code == EXIT_INIT_CHECK);
assert(_PyFrame_GetBytecode(shim)[1].op.code == RETURN_VALUE);
/* Push self onto stack of shim */
shim->localsplus[0] = PyStackRef_DUP(self[0]);
DEAD(init);
DEAD(self);
init_frame = _PyEvalFramePushAndInit(
_PyInterpreterFrame *temp = _PyEvalFramePushAndInit(
tstate, init[0], NULL, args-1, oparg+1, NULL, shim);
SYNC_SP();
if (init_frame == NULL) {
if (temp == NULL) {
_PyEval_FrameClearAndPop(tstate, shim);
ERROR_NO_POP();
}
init_frame = temp;
frame->return_offset = 1 + INLINE_CACHE_ENTRIES_CALL;
/* Account for pushing the extra frame.
* We don't check recursion depth here,
@ -4000,8 +4002,10 @@ dummy_func(
DEOPT_IF(callable_o != interp->callable_cache.list_append);
assert(self_o != NULL);
DEOPT_IF(!PyList_Check(self_o));
DEOPT_IF(!LOCK_OBJECT(self_o));
STAT_INC(CALL, hit);
int err = _PyList_AppendTakeRef((PyListObject *)self_o, PyStackRef_AsPyObjectSteal(arg));
UNLOCK_OBJECT(self_o);
PyStackRef_CLOSE(self);
PyStackRef_CLOSE(callable);
ERROR_IF(err, error);

21
Python/executor_cases.c.h generated
View file

@ -4500,13 +4500,13 @@
JUMP_TO_JUMP_TARGET();
}
PyTypeObject *tp = (PyTypeObject *)callable_o;
if (tp->tp_version_tag != type_version) {
if (FT_ATOMIC_LOAD_UINT32_RELAXED(tp->tp_version_tag) != type_version) {
UOP_STAT_INC(uopcode, miss);
JUMP_TO_JUMP_TARGET();
}
assert(tp->tp_flags & Py_TPFLAGS_INLINE_VALUES);
PyHeapTypeObject *cls = (PyHeapTypeObject *)callable_o;
PyFunctionObject *init_func = (PyFunctionObject *)cls->_spec_cache.init;
PyFunctionObject *init_func = (PyFunctionObject *)FT_ATOMIC_LOAD_PTR_ACQUIRE(cls->_spec_cache.init);
PyCodeObject *code = (PyCodeObject *)init_func->func_code;
if (!_PyThreadState_HasStackSpace(tstate, code->co_framesize + _Py_InitCleanup.co_framesize)) {
UOP_STAT_INC(uopcode, miss);
@ -4537,25 +4537,29 @@
_PyInterpreterFrame *shim = _PyFrame_PushTrampolineUnchecked(
tstate, (PyCodeObject *)&_Py_InitCleanup, 1, frame);
assert(_PyFrame_GetBytecode(shim)[0].op.code == EXIT_INIT_CHECK);
assert(_PyFrame_GetBytecode(shim)[1].op.code == RETURN_VALUE);
stack_pointer = _PyFrame_GetStackPointer(frame);
/* Push self onto stack of shim */
shim->localsplus[0] = PyStackRef_DUP(self[0]);
_PyFrame_SetStackPointer(frame, stack_pointer);
init_frame = _PyEvalFramePushAndInit(
_PyInterpreterFrame *temp = _PyEvalFramePushAndInit(
tstate, init[0], NULL, args-1, oparg+1, NULL, shim);
stack_pointer = _PyFrame_GetStackPointer(frame);
stack_pointer[-2 - oparg].bits = (uintptr_t)init_frame;
stack_pointer += -1 - oparg;
stack_pointer += -2 - oparg;
assert(WITHIN_STACK_BOUNDS());
if (init_frame == NULL) {
if (temp == NULL) {
_PyEval_FrameClearAndPop(tstate, shim);
JUMP_TO_ERROR();
}
init_frame = temp;
frame->return_offset = 1 + INLINE_CACHE_ENTRIES_CALL;
/* Account for pushing the extra frame.
* We don't check recursion depth here,
* as it will be checked after start_frame */
tstate->py_recursion_remaining--;
stack_pointer[0].bits = (uintptr_t)init_frame;
stack_pointer += 1;
assert(WITHIN_STACK_BOUNDS());
break;
}
@ -4908,8 +4912,13 @@
UOP_STAT_INC(uopcode, miss);
JUMP_TO_JUMP_TARGET();
}
if (!LOCK_OBJECT(self_o)) {
UOP_STAT_INC(uopcode, miss);
JUMP_TO_JUMP_TARGET();
}
STAT_INC(CALL, hit);
int err = _PyList_AppendTakeRef((PyListObject *)self_o, PyStackRef_AsPyObjectSteal(arg));
UNLOCK_OBJECT(self_o);
PyStackRef_CLOSE(self);
PyStackRef_CLOSE(callable);
if (err) JUMP_TO_ERROR();

21
Python/generated_cases.c.h generated
View file

@ -880,7 +880,7 @@
callable = &stack_pointer[-2 - oparg];
uint16_t counter = read_u16(&this_instr[1].cache);
(void)counter;
#if ENABLE_SPECIALIZATION
#if ENABLE_SPECIALIZATION_FT
if (ADAPTIVE_COUNTER_TRIGGERS(counter)) {
next_instr = this_instr;
_PyFrame_SetStackPointer(frame, stack_pointer);
@ -890,7 +890,7 @@
}
OPCODE_DEFERRED_INC(CALL);
ADVANCE_ADAPTIVE_COUNTER(this_instr[1].counter);
#endif /* ENABLE_SPECIALIZATION */
#endif /* ENABLE_SPECIALIZATION_FT */
}
/* Skip 2 cache entries */
// _MAYBE_EXPAND_METHOD
@ -1048,10 +1048,10 @@
DEOPT_IF(!PyStackRef_IsNull(null[0]), CALL);
DEOPT_IF(!PyType_Check(callable_o), CALL);
PyTypeObject *tp = (PyTypeObject *)callable_o;
DEOPT_IF(tp->tp_version_tag != type_version, CALL);
DEOPT_IF(FT_ATOMIC_LOAD_UINT32_RELAXED(tp->tp_version_tag) != type_version, CALL);
assert(tp->tp_flags & Py_TPFLAGS_INLINE_VALUES);
PyHeapTypeObject *cls = (PyHeapTypeObject *)callable_o;
PyFunctionObject *init_func = (PyFunctionObject *)cls->_spec_cache.init;
PyFunctionObject *init_func = (PyFunctionObject *)FT_ATOMIC_LOAD_PTR_ACQUIRE(cls->_spec_cache.init);
PyCodeObject *code = (PyCodeObject *)init_func->func_code;
DEOPT_IF(!_PyThreadState_HasStackSpace(tstate, code->co_framesize + _Py_InitCleanup.co_framesize), CALL);
STAT_INC(CALL, hit);
@ -1073,20 +1073,21 @@
_PyInterpreterFrame *shim = _PyFrame_PushTrampolineUnchecked(
tstate, (PyCodeObject *)&_Py_InitCleanup, 1, frame);
assert(_PyFrame_GetBytecode(shim)[0].op.code == EXIT_INIT_CHECK);
assert(_PyFrame_GetBytecode(shim)[1].op.code == RETURN_VALUE);
stack_pointer = _PyFrame_GetStackPointer(frame);
/* Push self onto stack of shim */
shim->localsplus[0] = PyStackRef_DUP(self[0]);
_PyFrame_SetStackPointer(frame, stack_pointer);
init_frame = _PyEvalFramePushAndInit(
_PyInterpreterFrame *temp = _PyEvalFramePushAndInit(
tstate, init[0], NULL, args-1, oparg+1, NULL, shim);
stack_pointer = _PyFrame_GetStackPointer(frame);
stack_pointer[-2 - oparg].bits = (uintptr_t)init_frame;
stack_pointer += -1 - oparg;
stack_pointer += -2 - oparg;
assert(WITHIN_STACK_BOUNDS());
if (init_frame == NULL) {
if (temp == NULL) {
_PyEval_FrameClearAndPop(tstate, shim);
goto error;
}
init_frame = temp;
frame->return_offset = 1 + INLINE_CACHE_ENTRIES_CALL;
/* Account for pushing the extra frame.
* We don't check recursion depth here,
@ -1100,8 +1101,6 @@
// Eventually this should be the only occurrence of this code.
assert(tstate->interp->eval_frame == NULL);
_PyInterpreterFrame *temp = new_frame;
stack_pointer += -1;
assert(WITHIN_STACK_BOUNDS());
_PyFrame_SetStackPointer(frame, stack_pointer);
assert(new_frame->previous == frame || new_frame->previous->previous == frame);
CALL_STAT_INC(inlined_py_calls);
@ -2383,8 +2382,10 @@
DEOPT_IF(callable_o != interp->callable_cache.list_append, CALL);
assert(self_o != NULL);
DEOPT_IF(!PyList_Check(self_o), CALL);
DEOPT_IF(!LOCK_OBJECT(self_o), CALL);
STAT_INC(CALL, hit);
int err = _PyList_AppendTakeRef((PyListObject *)self_o, PyStackRef_AsPyObjectSteal(arg));
UNLOCK_OBJECT(self_o);
PyStackRef_CLOSE(self);
PyStackRef_CLOSE(callable);
if (err) goto pop_3_error;

6
Python/perf_trampoline.c
View file

@ -484,11 +484,11 @@ _PyPerfTrampoline_Init(int activate)
return -1;
}
if (!activate) {
tstate->interp->eval_frame = NULL;
_PyInterpreterState_SetEvalFrameFunc(tstate->interp, NULL);
perf_status = PERF_STATUS_NO_INIT;
}
else {
tstate->interp->eval_frame = py_trampoline_evaluator;
_PyInterpreterState_SetEvalFrameFunc(tstate->interp, py_trampoline_evaluator);
if (new_code_arena() < 0) {
return -1;
}
@ -514,7 +514,7 @@ _PyPerfTrampoline_Fini(void)
}
PyThreadState *tstate = _PyThreadState_GET();
if (tstate->interp->eval_frame == py_trampoline_evaluator) {
tstate->interp->eval_frame = NULL;
_PyInterpreterState_SetEvalFrameFunc(tstate->interp, NULL);
}
if (perf_status == PERF_STATUS_OK) {
trampoline_api.free_state(trampoline_api.state);

2
Python/pystate.c
View file

@ -2838,7 +2838,9 @@ _PyInterpreterState_SetEvalFrameFunc(PyInterpreterState *interp,
}
#endif
RARE_EVENT_INC(set_eval_frame_func);
_PyEval_StopTheWorld(interp);
interp->eval_frame = eval_frame;
_PyEval_StartTheWorld(interp);
}

112
Python/specialize.c
View file

@ -1911,38 +1911,38 @@ _Py_Specialize_StoreSubscr(_PyStackRef container_st, _PyStackRef sub_st, _Py_COD
unspecialize(instr);
}
/* Returns a borrowed reference.
* The reference is only valid if guarded by a type version check.
*/
static PyFunctionObject *
get_init_for_simple_managed_python_class(PyTypeObject *tp)
/* Returns a strong reference. */
static PyObject *
get_init_for_simple_managed_python_class(PyTypeObject *tp, unsigned int *tp_version)
{
assert(tp->tp_new == PyBaseObject_Type.tp_new);
if (tp->tp_alloc != PyType_GenericAlloc) {
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_OVERRIDDEN);
return NULL;
}
if ((tp->tp_flags & Py_TPFLAGS_INLINE_VALUES) == 0) {
unsigned long tp_flags = PyType_GetFlags(tp);
if ((tp_flags & Py_TPFLAGS_INLINE_VALUES) == 0) {
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_CALL_INIT_NOT_INLINE_VALUES);
return NULL;
}
if (!(tp->tp_flags & Py_TPFLAGS_HEAPTYPE)) {
if (!(tp_flags & Py_TPFLAGS_HEAPTYPE)) {
/* Is this possible? */
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_EXPECTED_ERROR);
return NULL;
}
PyObject *init = _PyType_Lookup(tp, &_Py_ID(__init__));
PyObject *init = _PyType_LookupRefAndVersion(tp, &_Py_ID(__init__), tp_version);
if (init == NULL || !PyFunction_Check(init)) {
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_CALL_INIT_NOT_PYTHON);
Py_XDECREF(init);
return NULL;
}
int kind = function_kind((PyCodeObject *)PyFunction_GET_CODE(init));
if (kind != SIMPLE_FUNCTION) {
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_CALL_INIT_NOT_SIMPLE);
Py_DECREF(init);
return NULL;
}
((PyHeapTypeObject *)tp)->_spec_cache.init = init;
return (PyFunctionObject *)init;
return init;
}
static int
@ -1954,20 +1954,20 @@ specialize_class_call(PyObject *callable, _Py_CODEUNIT *instr, int nargs)
int oparg = instr->op.arg;
if (nargs == 1 && oparg == 1) {
if (tp == &PyUnicode_Type) {
instr->op.code = CALL_STR_1;
specialize(instr, CALL_STR_1);
return 0;
}
else if (tp == &PyType_Type) {
instr->op.code = CALL_TYPE_1;
specialize(instr, CALL_TYPE_1);
return 0;
}
else if (tp == &PyTuple_Type) {
instr->op.code = CALL_TUPLE_1;
specialize(instr, CALL_TUPLE_1);
return 0;
}
}
if (tp->tp_vectorcall != NULL) {
instr->op.code = CALL_BUILTIN_CLASS;
specialize(instr, CALL_BUILTIN_CLASS);
return 0;
}
goto generic;
@ -1976,19 +1976,25 @@ specialize_class_call(PyObject *callable, _Py_CODEUNIT *instr, int nargs)
goto generic;
}
if (tp->tp_new == PyBaseObject_Type.tp_new) {
PyFunctionObject *init = get_init_for_simple_managed_python_class(tp);
if (type_get_version(tp, CALL) == 0) {
unsigned int tp_version = 0;
PyObject *init = get_init_for_simple_managed_python_class(tp, &tp_version);
if (!tp_version) {
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_OUT_OF_VERSIONS);
Py_XDECREF(init);
return -1;
}
if (init != NULL) {
if (init != NULL && _PyType_CacheInitForSpecialization(
(PyHeapTypeObject *)tp, init, tp_version)) {
_PyCallCache *cache = (_PyCallCache *)(instr + 1);
write_u32(cache->func_version, tp->tp_version_tag);
_Py_SET_OPCODE(*instr, CALL_ALLOC_AND_ENTER_INIT);
write_u32(cache->func_version, tp_version);
specialize(instr, CALL_ALLOC_AND_ENTER_INIT);
Py_DECREF(init);
return 0;
}
Py_XDECREF(init);
}
generic:
instr->op.code = CALL_NON_PY_GENERAL;
specialize(instr, CALL_NON_PY_GENERAL);
return 0;
}
@ -2004,7 +2010,7 @@ specialize_method_descriptor(PyMethodDescrObject *descr, _Py_CODEUNIT *instr,
SPECIALIZATION_FAIL(CALL, SPEC_FAIL_WRONG_NUMBER_ARGUMENTS);
return -1;
}
instr->op.code = CALL_METHOD_DESCRIPTOR_NOARGS;
specialize(instr, CALL_METHOD_DESCRIPTOR_NOARGS);
return 0;
}
case METH_O: {
@ -2018,22 +2024,22 @@ specialize_method_descriptor(PyMethodDescrObject *descr, _Py_CODEUNIT *instr,
bool pop = (next.op.code == POP_TOP);
int oparg = instr->op.arg;
if ((PyObject *)descr == list_append && oparg == 1 && pop) {
instr->op.code = CALL_LIST_APPEND;
specialize(instr, CALL_LIST_APPEND);
return 0;
}
instr->op.code = CALL_METHOD_DESCRIPTOR_O;
specialize(instr, CALL_METHOD_DESCRIPTOR_O);
return 0;
}
case METH_FASTCALL: {
instr->op.code = CALL_METHOD_DESCRIPTOR_FAST;
specialize(instr, CALL_METHOD_DESCRIPTOR_FAST);
return 0;
}
case METH_FASTCALL | METH_KEYWORDS: {
instr->op.code = CALL_METHOD_DESCRIPTOR_FAST_WITH_KEYWORDS;
specialize(instr, CALL_METHOD_DESCRIPTOR_FAST_WITH_KEYWORDS);
return 0;
}
}
instr->op.code = CALL_NON_PY_GENERAL;
specialize(instr, CALL_NON_PY_GENERAL);
return 0;
}
@ -2063,12 +2069,15 @@ specialize_py_call(PyFunctionObject *func, _Py_CODEUNIT *instr, int nargs,
return -1;
}
write_u32(cache->func_version, version);
uint8_t opcode;
if (argcount == nargs + bound_method) {
instr->op.code = bound_method ? CALL_BOUND_METHOD_EXACT_ARGS : CALL_PY_EXACT_ARGS;
opcode =
bound_method ? CALL_BOUND_METHOD_EXACT_ARGS : CALL_PY_EXACT_ARGS;
}
else {
instr->op.code = bound_method ? CALL_BOUND_METHOD_GENERAL : CALL_PY_GENERAL;
opcode = bound_method ? CALL_BOUND_METHOD_GENERAL : CALL_PY_GENERAL;
}
specialize(instr, opcode);
return 0;
}
@ -2117,10 +2126,10 @@ specialize_c_call(PyObject *callable, _Py_CODEUNIT *instr, int nargs)
/* len(o) */
PyInterpreterState *interp = _PyInterpreterState_GET();
if (callable == interp->callable_cache.len) {
instr->op.code = CALL_LEN;
specialize(instr, CALL_LEN);
return 0;
}
instr->op.code = CALL_BUILTIN_O;
specialize(instr, CALL_BUILTIN_O);
return 0;
}
case METH_FASTCALL: {
@ -2128,19 +2137,19 @@ specialize_c_call(PyObject *callable, _Py_CODEUNIT *instr, int nargs)
/* isinstance(o1, o2) */
PyInterpreterState *interp = _PyInterpreterState_GET();
if (callable == interp->callable_cache.isinstance) {
instr->op.code = CALL_ISINSTANCE;
specialize(instr, CALL_ISINSTANCE);
return 0;
}
}
instr->op.code = CALL_BUILTIN_FAST;
specialize(instr, CALL_BUILTIN_FAST);
return 0;
}
case METH_FASTCALL | METH_KEYWORDS: {
instr->op.code = CALL_BUILTIN_FAST_WITH_KEYWORDS;
specialize(instr, CALL_BUILTIN_FAST_WITH_KEYWORDS);
return 0;
}
default:
instr->op.code = CALL_NON_PY_GENERAL;
specialize(instr, CALL_NON_PY_GENERAL);
return 0;
}
}
@ -2150,10 +2159,9 @@ _Py_Specialize_Call(_PyStackRef callable_st, _Py_CODEUNIT *instr, int nargs)
{
PyObject *callable = PyStackRef_AsPyObjectBorrow(callable_st);
assert(ENABLE_SPECIALIZATION);
assert(ENABLE_SPECIALIZATION_FT);
assert(_PyOpcode_Caches[CALL] == INLINE_CACHE_ENTRIES_CALL);
assert(_Py_OPCODE(*instr) != INSTRUMENTED_CALL);
_PyCallCache *cache = (_PyCallCache *)(instr + 1);
int fail;
if (PyCFunction_CheckExact(callable)) {
fail = specialize_c_call(callable, instr, nargs);
@ -2178,19 +2186,11 @@ _Py_Specialize_Call(_PyStackRef callable_st, _Py_CODEUNIT *instr, int nargs)
}
}
else {
instr->op.code = CALL_NON_PY_GENERAL;
specialize(instr, CALL_NON_PY_GENERAL);
fail = 0;
}
if (fail) {
STAT_INC(CALL, failure);
assert(!PyErr_Occurred());
instr->op.code = CALL;
cache->counter = adaptive_counter_backoff(cache->counter);
}
else {
STAT_INC(CALL, success);
assert(!PyErr_Occurred());
cache->counter = adaptive_counter_cooldown();
unspecialize(instr);
}
}
@ -2793,6 +2793,16 @@ _Py_Specialize_ContainsOp(_PyStackRef value_st, _Py_CODEUNIT *instr)
* Ends with a RESUME so that it is not traced.
* This is used as a plain code object, not a function,
* so must not access globals or builtins.
* There are a few other constraints imposed on the code
* by the free-threaded build:
*
* 1. The RESUME instruction must not be executed. Otherwise we may attempt to
* free the statically allocated TLBC array.
* 2. It must contain no specializable instructions. Specializing multiple
* copies of the same bytecode is not thread-safe in free-threaded builds.
*
* This should be dynamically allocated if either of those restrictions need to
* be lifted.
*/
#define NO_LOC_4 (128 | (PY_CODE_LOCATION_INFO_NONE << 3) | 3)
@ -2802,6 +2812,13 @@ static const PyBytesObject no_location = {
.ob_sval = { NO_LOC_4 }
};
#ifdef Py_GIL_DISABLED
static _PyCodeArray init_cleanup_tlbc = {
.size = 1,
.entries = {(char*) &_Py_InitCleanup.co_code_adaptive},
};
#endif
const struct _PyCode8 _Py_InitCleanup = {
_PyVarObject_HEAD_INIT(&PyCode_Type, 3),
.co_consts = (PyObject *)&_Py_SINGLETON(tuple_empty),
@ -2817,6 +2834,9 @@ const struct _PyCode8 _Py_InitCleanup = {
._co_firsttraceable = 4,
.co_stacksize = 2,
.co_framesize = 2 + FRAME_SPECIALS_SIZE,
#ifdef Py_GIL_DISABLED
.co_tlbc = &init_cleanup_tlbc,
#endif
.co_code_adaptive = {
EXIT_INIT_CHECK, 0,
RETURN_VALUE, 0,