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dict: Add dk_log2_index_bytes (GH-31439)

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Inada Naoki 2022-02-22 20:03:15 +09:00 committed by GitHub
parent 090e5c4b94
commit 1e344684d8
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2 changed files with 31 additions and 24 deletions
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5
Include/internal/pycore_dict.h
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@ -68,6 +68,9 @@ struct _dictkeysobject {
/* Size of the hash table (dk_indices). It must be a power of 2. */ /* Size of the hash table (dk_indices). It must be a power of 2. */
uint8_t dk_log2_size; uint8_t dk_log2_size;
/* Size of the hash table (dk_indices) by bytes. */
uint8_t dk_log2_index_bytes;
/* Kind of keys */ /* Kind of keys */
uint8_t dk_kind; uint8_t dk_kind;
@ -129,7 +132,7 @@ struct _dictvalues {
2 : sizeof(int32_t)) 2 : sizeof(int32_t))
#endif #endif
#define DK_ENTRIES(dk) \ #define DK_ENTRIES(dk) \
((PyDictKeyEntry*)(&((int8_t*)((dk)->dk_indices))[DK_SIZE(dk) * DK_IXSIZE(dk)])) ((PyDictKeyEntry*)(&((int8_t*)((dk)->dk_indices))[(size_t)1 << (dk)->dk_log2_index_bytes]))
extern uint64_t _pydict_global_version; extern uint64_t _pydict_global_version;

50
Objects/dictobject.c
View File

@ -16,19 +16,20 @@ As of Python 3.6, this is compact and ordered. Basic idea is described here:
layout: layout:
+---------------+ +---------------------+
| dk_refcnt | | dk_refcnt |
| dk_log2_size | | dk_log2_size |
| dk_kind | | dk_log2_index_bytes |
| dk_usable | | dk_kind |
| dk_nentries | | dk_usable |
+---------------+ | dk_nentries |
| dk_indices | +---------------------+
| | | dk_indices[] |
+---------------+ | |
| dk_entries | +---------------------+
| | | dk_entries[] |
+---------------+ | |
+---------------------+
dk_indices is actual hashtable. It holds index in entries, or DKIX_EMPTY(-1) dk_indices is actual hashtable. It holds index in entries, or DKIX_EMPTY(-1)
or DKIX_DUMMY(-2). or DKIX_DUMMY(-2).
@ -444,6 +445,7 @@ estimate_log2_keysize(Py_ssize_t n)
static PyDictKeysObject empty_keys_struct = { static PyDictKeysObject empty_keys_struct = {
1, /* dk_refcnt */ 1, /* dk_refcnt */
0, /* dk_log2_size */ 0, /* dk_log2_size */
0, /* dk_log2_index_bytes */
DICT_KEYS_SPLIT, /* dk_kind */ DICT_KEYS_SPLIT, /* dk_kind */
1, /* dk_version */ 1, /* dk_version */
0, /* dk_usable (immutable) */ 0, /* dk_usable (immutable) */
@ -562,24 +564,25 @@ static PyDictKeysObject*
new_keys_object(uint8_t log2_size) new_keys_object(uint8_t log2_size)
{ {
PyDictKeysObject *dk; PyDictKeysObject *dk;
Py_ssize_t es, usable; Py_ssize_t usable;
int log2_bytes;
assert(log2_size >= PyDict_LOG_MINSIZE); assert(log2_size >= PyDict_LOG_MINSIZE);
usable = USABLE_FRACTION(1<<log2_size); usable = USABLE_FRACTION(1<<log2_size);
if (log2_size <= 7) { if (log2_size < 8) {
es = 1; log2_bytes = log2_size;
} }
else if (log2_size <= 15) { else if (log2_size < 16) {
es = 2; log2_bytes = log2_size + 1;
} }
#if SIZEOF_VOID_P > 4 #if SIZEOF_VOID_P > 4
else if (log2_size <= 31) { else if (log2_size >= 32) {
es = 4; log2_bytes = log2_size + 3;
} }
#endif #endif
else { else {
es = sizeof(Py_ssize_t); log2_bytes = log2_size + 2;
} }
#if PyDict_MAXFREELIST > 0 #if PyDict_MAXFREELIST > 0
@ -595,7 +598,7 @@ new_keys_object(uint8_t log2_size)
#endif #endif
{ {
dk = PyObject_Malloc(sizeof(PyDictKeysObject) dk = PyObject_Malloc(sizeof(PyDictKeysObject)
+ (es<<log2_size) + ((size_t)1 << log2_bytes)
+ sizeof(PyDictKeyEntry) * usable); + sizeof(PyDictKeyEntry) * usable);
if (dk == NULL) { if (dk == NULL) {
PyErr_NoMemory(); PyErr_NoMemory();
@ -607,11 +610,12 @@ new_keys_object(uint8_t log2_size)
#endif #endif
dk->dk_refcnt = 1; dk->dk_refcnt = 1;
dk->dk_log2_size = log2_size; dk->dk_log2_size = log2_size;
dk->dk_log2_index_bytes = log2_bytes;
dk->dk_kind = DICT_KEYS_UNICODE; dk->dk_kind = DICT_KEYS_UNICODE;
dk->dk_nentries = 0; dk->dk_nentries = 0;
dk->dk_usable = usable; dk->dk_usable = usable;
dk->dk_version = 0; dk->dk_version = 0;
memset(&dk->dk_indices[0], 0xff, es<<log2_size); memset(&dk->dk_indices[0], 0xff, ((size_t)1 << log2_bytes));
memset(DK_ENTRIES(dk), 0, sizeof(PyDictKeyEntry) * usable); memset(DK_ENTRIES(dk), 0, sizeof(PyDictKeyEntry) * usable);
return dk; return dk;
} }