gh-102192: Replace PyErr_Fetch/Restore etc by more efficient alternatives (in Objects/) (#102218)

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Irit Katriel 2023-03-08 17:03:18 +00:00 committed by GitHub
parent b097925858
commit 11a2c6ce51
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GPG Key ID: 4AEE18F83AFDEB23
8 changed files with 51 additions and 106 deletions

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@ -119,7 +119,7 @@ As a consequence of this, split keys have a maximum size of 16.
#include "pycore_dict.h" // PyDictKeysObject
#include "pycore_gc.h" // _PyObject_GC_IS_TRACKED()
#include "pycore_object.h" // _PyObject_GC_TRACK()
#include "pycore_pyerrors.h" // _PyErr_Fetch()
#include "pycore_pyerrors.h" // _PyErr_GetRaisedException()
#include "pycore_pystate.h" // _PyThreadState_GET()
#include "stringlib/eq.h" // unicode_eq()

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@ -3781,16 +3781,13 @@ PyObject *
_PyErr_TrySetFromCause(const char *format, ...)
{
PyObject* msg_prefix;
PyObject *exc, *val, *tb;
PyTypeObject *caught_type;
PyObject *instance_args;
Py_ssize_t num_args, caught_type_size, base_exc_size;
PyObject *new_exc, *new_val, *new_tb;
va_list vargs;
int same_basic_size;
PyErr_Fetch(&exc, &val, &tb);
caught_type = (PyTypeObject *)exc;
PyObject *exc = PyErr_GetRaisedException();
PyTypeObject *caught_type = Py_TYPE(exc);
/* Ensure type info indicates no extra state is stored at the C level
* and that the type can be reinstantiated using PyErr_Format
*/
@ -3810,31 +3807,30 @@ _PyErr_TrySetFromCause(const char *format, ...)
* more state than just the exception type. Accordingly, we just
* leave it alone.
*/
PyErr_Restore(exc, val, tb);
PyErr_SetRaisedException(exc);
return NULL;
}
/* Check the args are empty or contain a single string */
PyErr_NormalizeException(&exc, &val, &tb);
instance_args = ((PyBaseExceptionObject *)val)->args;
instance_args = ((PyBaseExceptionObject *)exc)->args;
num_args = PyTuple_GET_SIZE(instance_args);
if (num_args > 1 ||
(num_args == 1 &&
!PyUnicode_CheckExact(PyTuple_GET_ITEM(instance_args, 0)))) {
/* More than 1 arg, or the one arg we do have isn't a string
*/
PyErr_Restore(exc, val, tb);
PyErr_SetRaisedException(exc);
return NULL;
}
/* Ensure the instance dict is also empty */
if (!_PyObject_IsInstanceDictEmpty(val)) {
if (!_PyObject_IsInstanceDictEmpty(exc)) {
/* While we could potentially copy a non-empty instance dictionary
* to the replacement exception, for now we take the more
* conservative path of leaving exceptions with attributes set
* alone.
*/
PyErr_Restore(exc, val, tb);
PyErr_SetRaisedException(exc);
return NULL;
}
@ -3847,28 +3843,19 @@ _PyErr_TrySetFromCause(const char *format, ...)
* types as well, but that's quite a bit trickier due to the extra
* state potentially stored on OSError instances.
*/
/* Ensure the traceback is set correctly on the existing exception */
if (tb != NULL) {
PyException_SetTraceback(val, tb);
Py_DECREF(tb);
}
va_start(vargs, format);
msg_prefix = PyUnicode_FromFormatV(format, vargs);
va_end(vargs);
if (msg_prefix == NULL) {
Py_DECREF(exc);
Py_DECREF(val);
return NULL;
}
PyErr_Format(exc, "%U (%s: %S)",
msg_prefix, Py_TYPE(val)->tp_name, val);
Py_DECREF(exc);
PyErr_Format((PyObject*)Py_TYPE(exc), "%U (%s: %S)",
msg_prefix, Py_TYPE(exc)->tp_name, exc);
Py_DECREF(msg_prefix);
PyErr_Fetch(&new_exc, &new_val, &new_tb);
PyErr_NormalizeException(&new_exc, &new_val, &new_tb);
PyException_SetCause(new_val, val);
PyErr_Restore(new_exc, new_val, new_tb);
return new_val;
PyObject *new_exc = PyErr_GetRaisedException();
PyException_SetCause(new_exc, exc);
PyErr_SetRaisedException(new_exc);
return new_exc;
}

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@ -1308,7 +1308,6 @@ _PyFrame_LocalsToFast(_PyInterpreterFrame *frame, int clear)
/* Merge locals into fast locals */
PyObject *locals;
PyObject **fast;
PyObject *error_type, *error_value, *error_traceback;
PyCodeObject *co;
locals = frame->f_locals;
if (locals == NULL) {
@ -1317,7 +1316,7 @@ _PyFrame_LocalsToFast(_PyInterpreterFrame *frame, int clear)
fast = _PyFrame_GetLocalsArray(frame);
co = frame->f_code;
PyErr_Fetch(&error_type, &error_value, &error_traceback);
PyObject *exc = PyErr_GetRaisedException();
for (int i = 0; i < co->co_nlocalsplus; i++) {
_PyLocals_Kind kind = _PyLocals_GetKind(co->co_localspluskinds, i);
@ -1374,7 +1373,7 @@ _PyFrame_LocalsToFast(_PyInterpreterFrame *frame, int clear)
}
Py_XDECREF(value);
}
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
}
void

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@ -69,8 +69,6 @@ void
_PyGen_Finalize(PyObject *self)
{
PyGenObject *gen = (PyGenObject *)self;
PyObject *res = NULL;
PyObject *error_type, *error_value, *error_traceback;
if (gen->gi_frame_state >= FRAME_COMPLETED) {
/* Generator isn't paused, so no need to close */
@ -82,23 +80,22 @@ _PyGen_Finalize(PyObject *self)
PyObject *finalizer = agen->ag_origin_or_finalizer;
if (finalizer && !agen->ag_closed) {
/* Save the current exception, if any. */
PyErr_Fetch(&error_type, &error_value, &error_traceback);
res = PyObject_CallOneArg(finalizer, self);
PyObject *exc = PyErr_GetRaisedException();
PyObject *res = PyObject_CallOneArg(finalizer, self);
if (res == NULL) {
PyErr_WriteUnraisable(self);
} else {
Py_DECREF(res);
}
/* Restore the saved exception. */
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
return;
}
}
/* Save the current exception, if any. */
PyErr_Fetch(&error_type, &error_value, &error_traceback);
PyObject *exc = PyErr_GetRaisedException();
/* If `gen` is a coroutine, and if it was never awaited on,
issue a RuntimeWarning. */
@ -109,20 +106,19 @@ _PyGen_Finalize(PyObject *self)
_PyErr_WarnUnawaitedCoroutine((PyObject *)gen);
}
else {
res = gen_close(gen, NULL);
}
if (res == NULL) {
if (PyErr_Occurred()) {
PyErr_WriteUnraisable(self);
PyObject *res = gen_close(gen, NULL);
if (res == NULL) {
if (PyErr_Occurred()) {
PyErr_WriteUnraisable(self);
}
}
else {
Py_DECREF(res);
}
}
else {
Py_DECREF(res);
}
/* Restore the saved exception. */
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
}
static void
@ -648,39 +644,11 @@ _PyGen_SetStopIterationValue(PyObject *value)
int
_PyGen_FetchStopIterationValue(PyObject **pvalue)
{
PyObject *et, *ev, *tb;
PyObject *value = NULL;
if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
PyErr_Fetch(&et, &ev, &tb);
if (ev) {
/* exception will usually be normalised already */
if (PyObject_TypeCheck(ev, (PyTypeObject *) et)) {
value = Py_NewRef(((PyStopIterationObject *)ev)->value);
Py_DECREF(ev);
} else if (et == PyExc_StopIteration && !PyTuple_Check(ev)) {
/* Avoid normalisation and take ev as value.
*
* Normalization is required if the value is a tuple, in
* that case the value of StopIteration would be set to
* the first element of the tuple.
*
* (See _PyErr_CreateException code for details.)
*/
value = ev;
} else {
/* normalisation required */
PyErr_NormalizeException(&et, &ev, &tb);
if (!PyObject_TypeCheck(ev, (PyTypeObject *)PyExc_StopIteration)) {
PyErr_Restore(et, ev, tb);
return -1;
}
value = Py_NewRef(((PyStopIterationObject *)ev)->value);
Py_DECREF(ev);
}
}
Py_XDECREF(et);
Py_XDECREF(tb);
PyObject *exc = PyErr_GetRaisedException();
value = Py_NewRef(((PyStopIterationObject *)exc)->value);
Py_DECREF(exc);
} else if (PyErr_Occurred()) {
return -1;
}

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@ -370,13 +370,12 @@ _PyObject_Dump(PyObject* op)
fflush(stderr);
PyGILState_STATE gil = PyGILState_Ensure();
PyObject *error_type, *error_value, *error_traceback;
PyErr_Fetch(&error_type, &error_value, &error_traceback);
PyObject *exc = PyErr_GetRaisedException();
(void)PyObject_Print(op, stderr, 0);
fflush(stderr);
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
PyGILState_Release(gil);
fprintf(stderr, "\n");
@ -860,25 +859,22 @@ set_attribute_error_context(PyObject* v, PyObject* name)
return 0;
}
// Intercept AttributeError exceptions and augment them to offer suggestions later.
PyObject *type, *value, *traceback;
PyErr_Fetch(&type, &value, &traceback);
PyErr_NormalizeException(&type, &value, &traceback);
// Check if the normalized exception is indeed an AttributeError
if (!PyErr_GivenExceptionMatches(value, PyExc_AttributeError)) {
PyObject *exc = PyErr_GetRaisedException();
if (!PyErr_GivenExceptionMatches(exc, PyExc_AttributeError)) {
goto restore;
}
PyAttributeErrorObject* the_exc = (PyAttributeErrorObject*) value;
PyAttributeErrorObject* the_exc = (PyAttributeErrorObject*) exc;
// Check if this exception was already augmented
if (the_exc->name || the_exc->obj) {
goto restore;
}
// Augment the exception with the name and object
if (PyObject_SetAttr(value, &_Py_ID(name), name) ||
PyObject_SetAttr(value, &_Py_ID(obj), v)) {
if (PyObject_SetAttr(exc, &_Py_ID(name), name) ||
PyObject_SetAttr(exc, &_Py_ID(obj), v)) {
return 1;
}
restore:
PyErr_Restore(type, value, traceback);
PyErr_SetRaisedException(exc);
return 0;
}
@ -2190,9 +2186,8 @@ Py_ReprLeave(PyObject *obj)
PyObject *dict;
PyObject *list;
Py_ssize_t i;
PyObject *error_type, *error_value, *error_traceback;
PyErr_Fetch(&error_type, &error_value, &error_traceback);
PyObject *exc = PyErr_GetRaisedException();
dict = PyThreadState_GetDict();
if (dict == NULL)
@ -2213,7 +2208,7 @@ Py_ReprLeave(PyObject *obj)
finally:
/* ignore exceptions because there is no way to report them. */
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
}
/* Trashcan support. */

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@ -1556,10 +1556,9 @@ _PyODict_SetItem_KnownHash(PyObject *od, PyObject *key, PyObject *value,
res = _odict_add_new_node((PyODictObject *)od, key, hash);
if (res < 0) {
/* Revert setting the value on the dict */
PyObject *exc, *val, *tb;
PyErr_Fetch(&exc, &val, &tb);
PyObject *exc = PyErr_GetRaisedException();
(void) _PyDict_DelItem_KnownHash(od, key, hash);
_PyErr_ChainExceptions(exc, val, tb);
_PyErr_ChainExceptions1(exc);
}
}
return res;

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@ -4397,10 +4397,9 @@ static void
type_dealloc_common(PyTypeObject *type)
{
if (type->tp_bases != NULL) {
PyObject *tp, *val, *tb;
PyErr_Fetch(&tp, &val, &tb);
PyObject *exc = PyErr_GetRaisedException();
remove_all_subclasses(type, type->tp_bases);
PyErr_Restore(tp, val, tb);
PyErr_SetRaisedException(exc);
}
}
@ -8445,10 +8444,9 @@ slot_tp_finalize(PyObject *self)
{
int unbound;
PyObject *del, *res;
PyObject *error_type, *error_value, *error_traceback;
/* Save the current exception, if any. */
PyErr_Fetch(&error_type, &error_value, &error_traceback);
PyObject *exc = PyErr_GetRaisedException();
/* Execute __del__ method, if any. */
del = lookup_maybe_method(self, &_Py_ID(__del__), &unbound);
@ -8462,7 +8460,7 @@ slot_tp_finalize(PyObject *self)
}
/* Restore the saved exception. */
PyErr_Restore(error_type, error_value, error_traceback);
PyErr_SetRaisedException(exc);
}
static PyObject *

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@ -959,9 +959,8 @@ PyObject_ClearWeakRefs(PyObject *object)
if (*list != NULL) {
PyWeakReference *current = *list;
Py_ssize_t count = _PyWeakref_GetWeakrefCount(current);
PyObject *err_type, *err_value, *err_tb;
PyObject *exc = PyErr_GetRaisedException();
PyErr_Fetch(&err_type, &err_value, &err_tb);
if (count == 1) {
PyObject *callback = current->wr_callback;
@ -980,7 +979,7 @@ PyObject_ClearWeakRefs(PyObject *object)
tuple = PyTuple_New(count * 2);
if (tuple == NULL) {
_PyErr_ChainExceptions(err_type, err_value, err_tb);
_PyErr_ChainExceptions1(exc);
return;
}
@ -1010,7 +1009,7 @@ PyObject_ClearWeakRefs(PyObject *object)
Py_DECREF(tuple);
}
assert(!PyErr_Occurred());
PyErr_Restore(err_type, err_value, err_tb);
PyErr_SetRaisedException(exc);
}
}