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bpo-45340: Don't create object dictionaries unless actually needed (GH-28802)

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* Never change types' cached keys. It could invalidate inline attribute objects.

* Lazily create object dictionaries.

* Update specialization of LOAD/STORE_ATTR.

* Don't update shared keys version for deletion of value.

* Update gdb support to handle instance values.

* Rename SPLIT_KEYS opcodes to INSTANCE_VALUE.
This commit is contained in:
Mark Shannon 2021-10-13 14:19:34 +01:00 • committed by GitHub
parent 97308dfcdc
commit a8b9350964
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GPG key ID: 4AEE18F83AFDEB23
18 changed files with 721 additions and 400 deletions
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434
Objects/dictobject.c
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@ -634,7 +634,7 @@ new_values(Py_ssize_t size)
/* Consumes a reference to the keys object */
static PyObject *
new_dict(PyDictKeysObject *keys, PyDictValues *values)
new_dict(PyDictKeysObject *keys, PyDictValues *values, Py_ssize_t used, int free_values_on_failure)
{
PyDictObject *mp;
assert(keys != NULL);
@ -653,7 +653,7 @@ new_dict(PyDictKeysObject *keys, PyDictValues *values)
mp = PyObject_GC_New(PyDictObject, &PyDict_Type);
if (mp == NULL) {
dictkeys_decref(keys);
if (values != empty_values) {
if (free_values_on_failure) {
free_values(values);
}
return NULL;
@ -661,12 +661,18 @@ new_dict(PyDictKeysObject *keys, PyDictValues *values)
}
mp->ma_keys = keys;
mp->ma_values = values;
mp->ma_used = 0;
mp->ma_used = used;
mp->ma_version_tag = DICT_NEXT_VERSION();
ASSERT_CONSISTENT(mp);
return (PyObject *)mp;
}
static inline Py_ssize_t
shared_keys_usable_size(PyDictKeysObject *keys)
{
return keys->dk_nentries + keys->dk_usable;
}
/* Consumes a reference to the keys object */
static PyObject *
new_dict_with_shared_keys(PyDictKeysObject *keys)
@ -674,7 +680,7 @@ new_dict_with_shared_keys(PyDictKeysObject *keys)
PyDictValues *values;
Py_ssize_t i, size;
size = USABLE_FRACTION(DK_SIZE(keys));
size = shared_keys_usable_size(keys);
values = new_values(size);
if (values == NULL) {
dictkeys_decref(keys);
@ -684,7 +690,7 @@ new_dict_with_shared_keys(PyDictKeysObject *keys)
for (i = 0; i < size; i++) {
values->values[i] = NULL;
}
return new_dict(keys, values);
return new_dict(keys, values, 0, 1);
}
@ -733,7 +739,7 @@ PyObject *
PyDict_New(void)
{
dictkeys_incref(Py_EMPTY_KEYS);
return new_dict(Py_EMPTY_KEYS, empty_values);
return new_dict(Py_EMPTY_KEYS, empty_values, 0, 0);
}
/* Search index of hash table from offset of entry table */
@ -998,6 +1004,40 @@ insertion_resize(PyDictObject *mp)
return dictresize(mp, calculate_log2_keysize(GROWTH_RATE(mp)));
}
static int
insert_into_dictkeys(PyDictKeysObject *keys, PyObject *name)
{
assert(PyUnicode_CheckExact(name));
Py_hash_t hash = ((PyASCIIObject *)name)->hash;
if (hash == -1) {
hash = PyUnicode_Type.tp_hash(name);
if (hash == -1) {
PyErr_Clear();
return DKIX_EMPTY;
}
}
Py_ssize_t ix = dictkeys_stringlookup(keys, name, hash);
if (ix == DKIX_EMPTY) {
if (keys->dk_usable <= 0) {
return DKIX_EMPTY;
}
Py_INCREF(name);
/* Insert into new slot. */
keys->dk_version = 0;
Py_ssize_t hashpos = find_empty_slot(keys, hash);
ix = keys->dk_nentries;
PyDictKeyEntry *ep = &DK_ENTRIES(keys)[ix];
dictkeys_set_index(keys, hashpos, ix);
assert(ep->me_key == NULL);
ep->me_key = name;
ep->me_hash = hash;
keys->dk_usable--;
keys->dk_nentries++;
}
assert (ix < SHARED_KEYS_MAX_SIZE);
return (int)ix;
}
/*
Internal routine to insert a new item into the table.
Used both by the internal resize routine and by the public insert routine.
@ -1043,7 +1083,7 @@ insertdict(PyDictObject *mp, PyObject *key, Py_hash_t hash, PyObject *value)
Py_ssize_t index = mp->ma_keys->dk_nentries;
assert(index < SHARED_KEYS_MAX_SIZE);
assert((mp->ma_values->mv_order >> 60) == 0);
mp->ma_values->mv_order = (mp->ma_values->mv_order)<<4 | index;
mp->ma_values->mv_order = ((mp->ma_values->mv_order)<<4) | index;
assert (mp->ma_values->values[index] == NULL);
mp->ma_values->values[index] = value;
}
@ -1144,8 +1184,7 @@ actually be smaller than the old one.
If a table is split (its keys and hashes are shared, its values are not),
then the values are temporarily copied into the table, it is resized as
a combined table, then the me_value slots in the old table are NULLed out.
After resizing a table is always combined,
but can be resplit by make_keys_shared().
After resizing a table is always combined.
*/
static int
dictresize(PyDictObject *mp, uint8_t log2_newsize)
@ -1186,19 +1225,16 @@ dictresize(PyDictObject *mp, uint8_t log2_newsize)
if (oldvalues != NULL) {
/* Convert split table into new combined table.
* We must incref keys; we can transfer values.
* Note that values of split table is always dense.
*/
for (Py_ssize_t i = 0; i < numentries; i++) {
int index = oldvalues->mv_order >> ((numentries-1-i)*4) & 15;
assert(oldvalues->values[index] != NULL);
int index = get_index_from_order(mp, i);
PyDictKeyEntry *ep = &oldentries[index];
PyObject *key = ep->me_key;
Py_INCREF(key);
newentries[i].me_key = key;
assert(oldvalues->values[index] != NULL);
Py_INCREF(ep->me_key);
newentries[i].me_key = ep->me_key;
newentries[i].me_hash = ep->me_hash;
newentries[i].me_value = oldvalues->values[index];
}
dictkeys_decref(oldkeys);
mp->ma_values = NULL;
if (oldvalues != empty_values) {
@ -1241,69 +1277,8 @@ dictresize(PyDictObject *mp, uint8_t log2_newsize)
build_indices(mp->ma_keys, newentries, numentries);
mp->ma_keys->dk_usable -= numentries;
mp->ma_keys->dk_nentries = numentries;
return 0;
}
/* Returns NULL if unable to split table.
* A NULL return does not necessarily indicate an error */
static PyDictKeysObject *
make_keys_shared(PyObject *op)
{
Py_ssize_t i;
Py_ssize_t size;
PyDictObject *mp = (PyDictObject *)op;
if (!PyDict_CheckExact(op))
return NULL;
if (mp->ma_used > SHARED_KEYS_MAX_SIZE) {
return NULL;
}
if (!_PyDict_HasSplitTable(mp)) {
PyDictKeyEntry *ep0;
PyDictValues *values;
assert(mp->ma_keys->dk_refcnt == 1);
if (mp->ma_keys->dk_kind == DICT_KEYS_GENERAL) {
return NULL;
}
else if (mp->ma_used > mp->ma_keys->dk_nentries) {
/* Remove dummy keys */
if (dictresize(mp, DK_LOG_SIZE(mp->ma_keys)))
return NULL;
}
assert(mp->ma_used == mp->ma_keys->dk_nentries);
/* Copy values into a new array */
ep0 = DK_ENTRIES(mp->ma_keys);
size = USABLE_FRACTION(DK_SIZE(mp->ma_keys));
values = new_values(size);
if (values == NULL) {
PyErr_SetString(PyExc_MemoryError,
"Not enough memory to allocate new values array");
return NULL;
}
uint64_t order = 0;
for (i = 0; i < mp->ma_used; i++) {
order <<= 4;
order |= i;
assert(ep0[i].me_value != NULL);
values->values[i] = ep0[i].me_value;
ep0[i].me_value = NULL;
}
values->mv_order = order;
for (; i < size; i++) {
assert(ep0[i].me_value == NULL);
values->values[i] = NULL;
ep0[i].me_value = NULL;
}
if (mp->ma_keys->dk_nentries + mp->ma_keys->dk_usable > SHARED_KEYS_MAX_SIZE) {
assert(mp->ma_keys->dk_nentries <= SHARED_KEYS_MAX_SIZE);
mp->ma_keys->dk_usable = SHARED_KEYS_MAX_SIZE - mp->ma_keys->dk_nentries;
}
mp->ma_keys->dk_kind = DICT_KEYS_SPLIT;
mp->ma_values = values;
}
dictkeys_incref(mp->ma_keys);
ASSERT_CONSISTENT(mp);
return mp->ma_keys;
return 0;
}
PyObject *
@ -1331,7 +1306,7 @@ _PyDict_NewPresized(Py_ssize_t minused)
new_keys = new_keys_object(log2_newsize);
if (new_keys == NULL)
return NULL;
return new_dict(new_keys, NULL);
return new_dict(new_keys, NULL, 0, 0);
}
/* Note that, for historical reasons, PyDict_GetItem() suppresses all errors
@ -1503,6 +1478,9 @@ _PyDict_GetItemStringWithError(PyObject *v, const char *key)
/* Fast version of global value lookup (LOAD_GLOBAL).
* Lookup in globals, then builtins.
*
*
*
*
* Raise an exception and return NULL if an error occurred (ex: computing the
* key hash failed, key comparison failed, ...). Return NULL if the key doesn't
* exist. Return the value if the key exists.
@ -1590,6 +1568,21 @@ _PyDict_SetItem_KnownHash(PyObject *op, PyObject *key, PyObject *value,
return insertdict(mp, key, hash, value);
}
static uint64_t
delete_index_from_order(uint64_t order, Py_ssize_t ix)
{ /* Update order */
for (int i = 0;; i+= 4) {
assert (i < 64);
if (((order >> i) & 15) == (uint64_t)ix) {
/* Remove 4 bits at ith position */
uint64_t high = ((order>>i)>>4)<<i;
uint64_t low = order & ((((uint64_t)1)<<i)-1);
return high | low;
}
}
Py_UNREACHABLE();
}
static int
delitem_common(PyDictObject *mp, Py_hash_t hash, Py_ssize_t ix,
PyObject *old_value)
@ -1601,7 +1594,6 @@ delitem_common(PyDictObject *mp, Py_hash_t hash, Py_ssize_t ix,
assert(hashpos >= 0);
mp->ma_used--;
mp->ma_keys->dk_version = 0;
mp->ma_version_tag = DICT_NEXT_VERSION();
ep = &DK_ENTRIES(mp->ma_keys)[ix];
if (mp->ma_values) {
@ -1609,19 +1601,12 @@ delitem_common(PyDictObject *mp, Py_hash_t hash, Py_ssize_t ix,
mp->ma_values->values[ix] = NULL;
assert(ix < SHARED_KEYS_MAX_SIZE);
/* Update order */
for (int i = 0;; i+= 4) {
assert (i < 64);
if (((mp->ma_values->mv_order >> i) & 15) == (uint64_t)ix) {
/* Remove 4 bits at ith position */
uint64_t order = mp->ma_values->mv_order;
uint64_t high = ((order>>i)>>4)<<i;
uint64_t low = order & ((((uint64_t)1)<<i)-1);
mp->ma_values->mv_order = high | low;
break;
}
}
mp->ma_values->mv_order =
delete_index_from_order(mp->ma_values->mv_order, ix);
ASSERT_CONSISTENT(mp);
}
else {
mp->ma_keys->dk_version = 0;
dictkeys_set_index(mp->ma_keys, hashpos, DKIX_DUMMY);
old_key = ep->me_key;
ep->me_key = NULL;
@ -2692,7 +2677,7 @@ PyDict_Copy(PyObject *o)
if (_PyDict_HasSplitTable(mp)) {
PyDictObject *split_copy;
Py_ssize_t size = USABLE_FRACTION(DK_SIZE(mp->ma_keys));
Py_ssize_t size = shared_keys_usable_size(mp->ma_keys);
PyDictValues *newvalues;
newvalues = new_values(size);
if (newvalues == NULL)
@ -2740,7 +2725,7 @@ PyDict_Copy(PyObject *o)
if (keys == NULL) {
return NULL;
}
PyDictObject *new = (PyDictObject *)new_dict(keys, NULL);
PyDictObject *new = (PyDictObject *)new_dict(keys, NULL, 0, 0);
if (new == NULL) {
/* In case of an error, `new_dict()` takes care of
cleaning up `keys`. */
@ -2979,15 +2964,6 @@ PyDict_SetDefault(PyObject *d, PyObject *key, PyObject *defaultobj)
if (ix == DKIX_ERROR)
return NULL;
if (_PyDict_HasSplitTable(mp) &&
((ix >= 0 && value == NULL && mp->ma_used != ix) ||
(ix == DKIX_EMPTY && mp->ma_used != mp->ma_keys->dk_nentries))) {
if (insertion_resize(mp) < 0) {
return NULL;
}
ix = DKIX_EMPTY;
}
if (ix == DKIX_EMPTY) {
mp->ma_keys->dk_version = 0;
PyDictKeyEntry *ep, *ep0;
@ -3028,7 +3004,7 @@ PyDict_SetDefault(PyObject *d, PyObject *key, PyObject *defaultobj)
else if (value == NULL) {
value = defaultobj;
assert(_PyDict_HasSplitTable(mp));
assert(ix == mp->ma_used);
assert(mp->ma_values->values[ix] == NULL);
Py_INCREF(value);
MAINTAIN_TRACKING(mp, key, value);
mp->ma_values->values[ix] = value;
@ -3204,20 +3180,22 @@ static PyObject *dictiter_new(PyDictObject *, PyTypeObject *);
Py_ssize_t
_PyDict_SizeOf(PyDictObject *mp)
{
Py_ssize_t size, usable, res;
Py_ssize_t size, res;
size = DK_SIZE(mp->ma_keys);
usable = USABLE_FRACTION(size);
res = _PyObject_SIZE(Py_TYPE(mp));
if (mp->ma_values)
res += usable * sizeof(PyObject*);
if (mp->ma_values) {
res += shared_keys_usable_size(mp->ma_keys) * sizeof(PyObject*);
}
/* If the dictionary is split, the keys portion is accounted-for
in the type object. */
if (mp->ma_keys->dk_refcnt == 1)
if (mp->ma_keys->dk_refcnt == 1) {
Py_ssize_t usable = USABLE_FRACTION(size);
res += (sizeof(PyDictKeysObject)
+ DK_IXSIZE(mp->ma_keys) * size
+ sizeof(PyDictKeyEntry) * usable);
}
return res;
}
@ -4919,11 +4897,14 @@ dictvalues_reversed(_PyDictViewObject *dv, PyObject *Py_UNUSED(ignored))
PyDictKeysObject *
_PyDict_NewKeysForClass(void)
{
PyDictKeysObject *keys = new_keys_object(PyDict_LOG_MINSIZE);
PyDictKeysObject *keys = new_keys_object(5); /* log2(32) */
if (keys == NULL) {
PyErr_Clear();
}
else {
assert(keys->dk_nentries == 0);
/* Set to max size+1 as it will shrink by one before each new object */
keys->dk_usable = SHARED_KEYS_MAX_SIZE;
keys->dk_kind = DICT_KEYS_SPLIT;
}
return keys;
@ -4931,15 +4912,42 @@ _PyDict_NewKeysForClass(void)
#define CACHED_KEYS(tp) (((PyHeapTypeObject*)tp)->ht_cached_keys)
static int
init_inline_values(PyObject *obj, PyTypeObject *tp)
{
assert(tp->tp_flags & Py_TPFLAGS_HEAPTYPE);
assert(tp->tp_dictoffset > 0);
assert(tp->tp_inline_values_offset > 0);
PyDictKeysObject *keys = CACHED_KEYS(tp);
assert(keys != NULL);
if (keys->dk_usable > 1) {
keys->dk_usable--;
}
Py_ssize_t size = shared_keys_usable_size(keys);
assert(size > 0);
PyDictValues *values = new_values(size);
if (values == NULL) {
PyErr_NoMemory();
return -1;
}
values->mv_order = 0;
for (int i = 0; i < size; i++) {
values->values[i] = NULL;
}
*((PyDictValues **)((char *)obj + tp->tp_inline_values_offset)) = values;
return 0;
}
int
_PyObject_InitializeDict(PyObject *obj)
{
PyObject **dictptr = _PyObject_GetDictPtr(obj);
if (dictptr == NULL) {
PyTypeObject *tp = Py_TYPE(obj);
if (tp->tp_dictoffset == 0) {
return 0;
}
assert(*dictptr == NULL);
PyTypeObject *tp = Py_TYPE(obj);
if (tp->tp_inline_values_offset) {
return init_inline_values(obj, tp);
}
PyObject *dict;
if (_PyType_HasFeature(tp, Py_TPFLAGS_HEAPTYPE) && CACHED_KEYS(tp)) {
dictkeys_incref(CACHED_KEYS(tp));
@ -4951,15 +4959,174 @@ _PyObject_InitializeDict(PyObject *obj)
if (dict == NULL) {
return -1;
}
PyObject **dictptr = _PyObject_DictPointer(obj);
*dictptr = dict;
return 0;
}
static PyObject *
make_dict_from_instance_attributes(PyDictKeysObject *keys, PyDictValues *values)
{
dictkeys_incref(keys);
Py_ssize_t used = 0;
Py_ssize_t track = 0;
for (Py_ssize_t i = 0; i < shared_keys_usable_size(keys); i++) {
PyObject *val = values->values[i];
if (val != NULL) {
used += 1;
track += _PyObject_GC_MAY_BE_TRACKED(val);
}
}
PyObject *res = new_dict(keys, values, used, 0);
if (track && res) {
_PyObject_GC_TRACK(res);
}
return res;
}
PyObject *
_PyObject_MakeDictFromInstanceAttributes(PyObject *obj, PyDictValues *values)
{
assert(Py_TYPE(obj)->tp_inline_values_offset != 0);
PyDictKeysObject *keys = CACHED_KEYS(Py_TYPE(obj));
return make_dict_from_instance_attributes(keys, values);
}
int
_PyObject_StoreInstanceAttribute(PyObject *obj, PyDictValues *values,
PyObject *name, PyObject *value)
{
assert(PyUnicode_CheckExact(name));
PyTypeObject *tp = Py_TYPE(obj);
PyDictKeysObject *keys = CACHED_KEYS(Py_TYPE(obj));
assert(keys != NULL);
assert(values != NULL);
int ix = insert_into_dictkeys(keys, name);
if (ix == DKIX_EMPTY) {
if (value == NULL) {
PyErr_SetObject(PyExc_AttributeError, name);
return -1;
}
PyObject *dict = make_dict_from_instance_attributes(keys, values);
if (dict == NULL) {
return -1;
}
*((PyDictValues **)((char *)obj + tp->tp_inline_values_offset)) = NULL;
*((PyObject **) ((char *)obj + tp->tp_dictoffset)) = dict;
return PyDict_SetItem(dict, name, value);
}
PyObject *old_value = values->values[ix];
Py_XINCREF(value);
values->values[ix] = value;
if (old_value == NULL) {
if (value == NULL) {
PyErr_SetObject(PyExc_AttributeError, name);
return -1;
}
values->mv_order = (values->mv_order << 4) | ix;
}
else {
if (value == NULL) {
values->mv_order = delete_index_from_order(values->mv_order, ix);
}
Py_DECREF(old_value);
}
return 0;
}
PyObject *
_PyObject_GetInstanceAttribute(PyObject *obj, PyDictValues *values,
PyObject *name)
{
assert(PyUnicode_CheckExact(name));
PyDictKeysObject *keys = CACHED_KEYS(Py_TYPE(obj));
assert(keys != NULL);
Py_ssize_t ix = _PyDictKeys_StringLookup(keys, name);
if (ix == DKIX_EMPTY) {
return NULL;
}
PyObject *value = values->values[ix];
Py_XINCREF(value);
return value;
}
int
_PyObject_IsInstanceDictEmpty(PyObject *obj)
{
PyTypeObject *tp = Py_TYPE(obj);
if (tp->tp_dictoffset == 0) {
return 1;
}
PyDictValues **values_ptr = _PyObject_ValuesPointer(obj);
if (values_ptr && *values_ptr) {
PyDictKeysObject *keys = CACHED_KEYS(tp);
for (Py_ssize_t i = 0; i < keys->dk_nentries; i++) {
if ((*values_ptr)->values[i] != NULL) {
return 0;
}
}
return 1;
}
PyObject **dictptr = _PyObject_DictPointer(obj);
PyObject *dict = *dictptr;
if (dict == NULL) {
return 1;
}
return ((PyDictObject *)dict)->ma_used == 0;
}
int
_PyObject_VisitInstanceAttributes(PyObject *self, visitproc visit, void *arg)
{
PyTypeObject *tp = Py_TYPE(self);
assert(tp->tp_inline_values_offset);
PyDictValues **values_ptr = _PyObject_ValuesPointer(self);
if (*values_ptr == NULL) {
return 0;
}
PyDictKeysObject *keys = CACHED_KEYS(tp);
for (Py_ssize_t i = 0; i < keys->dk_nentries; i++) {
Py_VISIT((*values_ptr)->values[i]);
}
return 0;
}
void
_PyObject_ClearInstanceAttributes(PyObject *self)
{
PyTypeObject *tp = Py_TYPE(self);
assert(tp->tp_inline_values_offset);
PyDictValues **values_ptr = _PyObject_ValuesPointer(self);
if (*values_ptr == NULL) {
return;
}
PyDictKeysObject *keys = CACHED_KEYS(tp);
for (Py_ssize_t i = 0; i < keys->dk_nentries; i++) {
Py_CLEAR((*values_ptr)->values[i]);
}
}
void
_PyObject_FreeInstanceAttributes(PyObject *self)
{
PyTypeObject *tp = Py_TYPE(self);
assert(tp->tp_inline_values_offset);
PyDictValues **values_ptr = _PyObject_ValuesPointer(self);
if (*values_ptr == NULL) {
return;
}
PyDictKeysObject *keys = CACHED_KEYS(tp);
for (Py_ssize_t i = 0; i < keys->dk_nentries; i++) {
Py_XDECREF((*values_ptr)->values[i]);
}
free_values(*values_ptr);
}
PyObject *
PyObject_GenericGetDict(PyObject *obj, void *context)
{
PyObject **dictptr = _PyObject_GetDictPtr(obj);
PyObject **dictptr = _PyObject_DictPointer(obj);
if (dictptr == NULL) {
PyErr_SetString(PyExc_AttributeError,
"This object has no __dict__");
@ -4968,7 +5135,14 @@ PyObject_GenericGetDict(PyObject *obj, void *context)
PyObject *dict = *dictptr;
if (dict == NULL) {
PyTypeObject *tp = Py_TYPE(obj);
if (_PyType_HasFeature(tp, Py_TPFLAGS_HEAPTYPE) && CACHED_KEYS(tp)) {
PyDictValues **values_ptr = _PyObject_ValuesPointer(obj);
if (values_ptr && *values_ptr) {
*dictptr = dict = make_dict_from_instance_attributes(CACHED_KEYS(tp), *values_ptr);
if (dict != NULL) {
*values_ptr = NULL;
}
}
else if (_PyType_HasFeature(tp, Py_TPFLAGS_HEAPTYPE) && CACHED_KEYS(tp)) {
dictkeys_incref(CACHED_KEYS(tp));
*dictptr = dict = new_dict_with_shared_keys(CACHED_KEYS(tp));
}
@ -5003,37 +5177,7 @@ _PyObjectDict_SetItem(PyTypeObject *tp, PyObject **dictptr,
res = PyDict_DelItem(dict, key);
}
else {
int was_shared = (cached == ((PyDictObject *)dict)->ma_keys);
res = PyDict_SetItem(dict, key, value);
if (was_shared &&
(cached = CACHED_KEYS(tp)) != NULL &&
cached != ((PyDictObject *)dict)->ma_keys &&
cached->dk_nentries <= SHARED_KEYS_MAX_SIZE) {
/* PyDict_SetItem() may call dictresize and convert split table
* into combined table. In such case, convert it to split
* table again and update type's shared key only when this is
* the only dict sharing key with the type.
*
* This is to allow using shared key in class like this:
*
* class C:
* def __init__(self):
* # one dict resize happens
* self.a, self.b, self.c = 1, 2, 3
* self.d, self.e, self.f = 4, 5, 6
* a = C()
*/
if (cached->dk_refcnt == 1) {
PyDictKeysObject *new_cached = make_keys_shared(dict);
if (new_cached != NULL) {
CACHED_KEYS(tp) = new_cached;
dictkeys_decref(cached);
}
else if (PyErr_Occurred()) {
return -1;
}
}
}
}
} else {
dict = *dictptr;