Issue #25629: Move set fill/used updates out of inner loop

This commit is contained in:
Raymond Hettinger 2015-11-17 08:28:07 -08:00
parent 9ba97df69c
commit 6019c8ced0

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@ -254,9 +254,10 @@ set_add_entry(PySetObject *so, PyObject *key, Py_hash_t hash)
Internal routine used by set_table_resize() to insert an item which is
known to be absent from the set. This routine also assumes that
the set contains no deleted entries. Besides the performance benefit,
using set_insert_clean() in set_table_resize() is dangerous (SF bug #1456209).
Note that no refcounts are changed by this routine; if needed, the caller
is responsible for incref'ing `key`.
there is also safety benefit since using set_add_entry() risks making
a callback in the middle of a set_table_resize(), see issue 1456209.
The caller is responsible for updating the key's reference count and
the setobject's fill and used fields.
*/
static void
set_insert_clean(PySetObject *so, PyObject *key, Py_hash_t hash)
@ -285,8 +286,6 @@ set_insert_clean(PySetObject *so, PyObject *key, Py_hash_t hash)
found_null:
entry->key = key;
entry->hash = hash;
so->fill++;
so->used++;
}
/* ======== End logic for probing the hash table ========================== */
@ -356,8 +355,8 @@ set_table_resize(PySetObject *so, Py_ssize_t minused)
/* Make the set empty, using the new table. */
assert(newtable != oldtable);
memset(newtable, 0, sizeof(setentry) * newsize);
so->fill = 0;
so->used = 0;
so->fill = oldused;
so->used = oldused;
so->mask = newsize - 1;
so->table = newtable;
@ -676,6 +675,8 @@ set_merge(PySetObject *so, PyObject *otherset)
/* If our table is empty, we can use set_insert_clean() */
if (so->fill == 0) {
so->fill = other->used;
so->used = other->used;
for (i = 0; i <= other->mask; i++, other_entry++) {
key = other_entry->key;
if (key != NULL && key != dummy) {