bpo-31954: Reuse oldkeys if oldkeys->dk_size == newsize. (alt)

Include/dictobject.h

@@ -120,7 +120,7 @@ PyAPI_FUNC(PyObject *) _PyDict_Pop(PyObject *, PyObject *, PyObject *);
 PyObject *_PyDict_Pop_KnownHash(PyObject *, PyObject *, Py_hash_t, PyObject *);
 PyObject *_PyDict_FromKeys(PyObject *, PyObject *, PyObject *);
 #define _PyDict_HasSplitTable(d) ((d)->ma_values != NULL)
-
+PyAPI_FUNC(Py_ssize_t) _PyDict_GetIndex(PyDictObject *, PyObject *, Py_hash_t);
 PyAPI_FUNC(int) PyDict_ClearFreeList(void);
 #endif
 

Lib/test/test_ordered_dict.py

@@ -676,7 +676,7 @@ def test_sizeof_exact(self):
         size = support.calcobjsize
         check = self.check_sizeof
 
-        basicsize = size('nQ2P' + '3PnPn2P') + calcsize('2nP2n')
+        basicsize = size('nQ2P' + '3Pn2P') + calcsize('4nI0P')
 
         entrysize = calcsize('n2P')
         p = calcsize('P')

Lib/test/test_sys.py

@@ -965,9 +965,9 @@ def inner():
         # method-wrapper (descriptor object)
         check({}.__iter__, size('2P'))
         # dict
-        check({}, size('nQ2P') + calcsize('2nP2n') + 8 + (8*2//3)*calcsize('n2P'))
+        check({}, size('nQ2P') + calcsize('4nI0P') + 8 + (8*2//3)*calcsize('n2P'))
         longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8}
-        check(longdict, size('nQ2P') + calcsize('2nP2n') + 16 + (16*2//3)*calcsize('n2P'))
+        check(longdict, size('nQ2P') + calcsize('4nI0P') + 16 + (16*2//3)*calcsize('n2P'))
         # dictionary-keyview
         check({}.keys(), size('P'))
         # dictionary-valueview
@@ -1128,13 +1128,13 @@ def delx(self): del self.__x
                   '4P')
         class newstyleclass(object): pass
         # Separate block for PyDictKeysObject with 8 keys and 5 entries
-        check(newstyleclass, s + calcsize("2nP2n0P") + 8 + 5*calcsize("n2P"))
+        check(newstyleclass, s + calcsize("4nI0P") + 8 + 5*calcsize("n2P"))
         # dict with shared keys
         check(newstyleclass().__dict__, size('nQ2P') + 5*self.P)
         o = newstyleclass()
         o.a = o.b = o.c = o.d = o.e = o.f = o.g = o.h = 1
         # Separate block for PyDictKeysObject with 16 keys and 10 entries
-        check(newstyleclass, s + calcsize("2nP2n0P") + 16 + 10*calcsize("n2P"))
+        check(newstyleclass, s + calcsize("4nI0P") + 16 + 10*calcsize("n2P"))
         # dict with shared keys
         check(newstyleclass().__dict__, size('nQ2P') + 10*self.P)
         # unicode

Objects/dict-common.h

@@ -8,12 +8,6 @@ typedef struct {
     PyObject *me_value; /* This field is only meaningful for combined tables */
 } PyDictKeyEntry;
 
-/* dict_lookup_func() returns index of entry which can be used like DK_ENTRIES(dk)[index].
- * -1 when no entry found, -3 when compare raises error.
- */
-typedef Py_ssize_t (*dict_lookup_func)
-    (PyDictObject *mp, PyObject *key, Py_hash_t hash, PyObject **value_addr);
-
 #define DKIX_EMPTY (-1)
 #define DKIX_DUMMY (-2)  /* Used internally */
 #define DKIX_ERROR (-3)
@@ -25,6 +19,12 @@ struct _dictkeysobject {
     /* Size of the hash table (dk_indices). It must be a power of 2. */
     Py_ssize_t dk_size;
 
+    /* Number of usable entries in dk_entries. */
+    Py_ssize_t dk_usable;
+
+    /* Number of used entries in dk_entries. */
+    Py_ssize_t dk_nentries;
+
     /* Function to lookup in the hash table (dk_indices):
 
        - lookdict(): general-purpose, and may return DKIX_ERROR if (and
@@ -38,13 +38,10 @@ struct _dictkeysobject {
          specialized for Unicode string keys that cannot be the <dummy> value.
 
        - lookdict_split(): Version of lookdict() for split tables. */
-    dict_lookup_func dk_lookup;
-
-    /* Number of usable entries in dk_entries. */
-    Py_ssize_t dk_usable;
+    unsigned int dk_lookup: 8;
 
-    /* Number of used entries in dk_entries. */
-    Py_ssize_t dk_nentries;
+    /* Whether OrderedDict's cache is synchronized with dict table */
+    unsigned int dk_clean: 1;
 
     /* Actual hash table of dk_size entries. It holds indices in dk_entries,
        or DKIX_EMPTY(-1) or DKIX_DUMMY(-2).