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author | Raymond Hettinger <python@rcn.com> | 2005-08-13 08:28:03 (GMT) |
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committer | Raymond Hettinger <python@rcn.com> | 2005-08-13 08:28:03 (GMT) |
commit | ed6c1ef8c3ca1b75579b5f451c38c15f990d2e28 (patch) | |
tree | 93426518c640094bfe140e680d6368e63f3dac4b /Objects | |
parent | 00148226df1af0f6ef120492c07fb5a8013087fc (diff) | |
download | cpython-ed6c1ef8c3ca1b75579b5f451c38c15f990d2e28.zip cpython-ed6c1ef8c3ca1b75579b5f451c38c15f990d2e28.tar.gz cpython-ed6c1ef8c3ca1b75579b5f451c38c15f990d2e28.tar.bz2 |
* Bring lookkey() and lookkey_string() closer to dict version.
* Use set_next() for looping in issubset() and frozenset_hash().
* Re-order the presentation of cmp and hash functions.
Diffstat (limited to 'Objects')
-rw-r--r-- | Objects/setobject.c | 170 |
1 files changed, 77 insertions, 93 deletions
diff --git a/Objects/setobject.c b/Objects/setobject.c index 7cfd2a9..9f07cb1 100644 --- a/Objects/setobject.c +++ b/Objects/setobject.c @@ -61,6 +61,7 @@ set_lookkey(PySetObject *so, PyObject *key, register long hash) setentry *table = so->table; register setentry *entry; register int restore_error; + register int checked_error; register int cmp; PyObject *err_type, *err_value, *err_tb; PyObject *startkey; @@ -70,11 +71,13 @@ set_lookkey(PySetObject *so, PyObject *key, register long hash) if (entry->key == NULL || entry->key == key) return entry; - restore_error = 0; + restore_error = checked_error = 0; if (entry->key == dummy) freeslot = entry; else { if (entry->hash == hash) { + /* error can't have been checked yet */ + checked_error = 1; if (_PyErr_OCCURRED()) { restore_error = 1; PyErr_Fetch(&err_type, &err_value, &err_tb); @@ -111,10 +114,13 @@ set_lookkey(PySetObject *so, PyObject *key, register long hash) if (entry->key == key) break; if (entry->hash == hash && entry->key != dummy) { - if (_PyErr_OCCURRED()) { - restore_error = 1; - PyErr_Fetch(&err_type, &err_value, - &err_tb); + if (!checked_error) { + checked_error = 1; + if (_PyErr_OCCURRED()) { + restore_error = 1; + PyErr_Fetch(&err_type, &err_value, + &err_tb); + } } startkey = entry->key; cmp = PyObject_RichCompareBool(startkey, key, Py_EQ); @@ -174,44 +180,28 @@ set_lookkey_string(PySetObject *so, PyObject *key, register long hash) entry = &table[i]; if (entry->key == NULL || entry->key == key) return entry; - if (so->fill != so->used) { - if (entry->key == dummy) - freeslot = entry; - else { - if (entry->hash == hash && _PyString_Eq(entry->key, key)) - return entry; - freeslot = NULL; - } - - /* In the loop, key == dummy is by far (factor of 100s) the - least likely outcome, so test for that last. */ - for (perturb = hash; ; perturb >>= PERTURB_SHIFT) { - i = (i << 2) + i + perturb + 1; - entry = &table[i & mask]; - if (entry->key == NULL) - return freeslot == NULL ? entry : freeslot; - if (entry->key == key - || (entry->hash == hash - && entry->key != dummy - && _PyString_Eq(entry->key, key))) - return entry; - if (entry->key == dummy && freeslot == NULL) - freeslot = entry; - } - } else { - /* Simplified loop when there are no dummy entries. */ + if (entry->key == dummy) + freeslot = entry; + else { if (entry->hash == hash && _PyString_Eq(entry->key, key)) return entry; - for (perturb = hash; ; perturb >>= PERTURB_SHIFT) { - i = (i << 2) + i + perturb + 1; - entry = &table[i & mask]; - if (entry->key == NULL) - return entry; - if (entry->key == key - || (entry->hash == hash - && _PyString_Eq(entry->key, key))) - return entry; - } + freeslot = NULL; + } + + /* In the loop, key == dummy is by far (factor of 100s) the + least likely outcome, so test for that last. */ + for (perturb = hash; ; perturb >>= PERTURB_SHIFT) { + i = (i << 2) + i + perturb + 1; + entry = &table[i & mask]; + if (entry->key == NULL) + return freeslot == NULL ? entry : freeslot; + if (entry->key == key + || (entry->hash == hash + && entry->key != dummy + && _PyString_Eq(entry->key, key))) + return entry; + if (entry->key == dummy && freeslot == NULL) + freeslot = entry; } } @@ -1369,11 +1359,11 @@ set_ixor(PySetObject *so, PyObject *other) static PyObject * set_issubset(PySetObject *so, PyObject *other) { - PyObject *tmp, *result; - register setentry *entry; - register int i; + setentry *entry; + int pos = 0; if (!PyAnySet_Check(other)) { + PyObject *tmp, *result; tmp = make_new_set(&PySet_Type, other); if (tmp == NULL) return NULL; @@ -1384,10 +1374,7 @@ set_issubset(PySetObject *so, PyObject *other) if (set_len((PyObject *)so) > set_len(other)) Py_RETURN_FALSE; - entry = &so->table[0]; - for (i=so->used ; i ; entry++, i--) { - while (entry->key == NULL || entry->key==dummy) - entry++; + while (set_next(so, &pos, &entry)) { if (!set_contains_entry((PySetObject *)other, entry)) Py_RETURN_FALSE; } @@ -1414,51 +1401,6 @@ set_issuperset(PySetObject *so, PyObject *other) PyDoc_STRVAR(issuperset_doc, "Report whether this set contains another set."); -static long -set_nohash(PyObject *self) -{ - PyErr_SetString(PyExc_TypeError, "set objects are unhashable"); - return -1; -} - -static int -set_nocmp(PyObject *self) -{ - PyErr_SetString(PyExc_TypeError, "cannot compare sets using cmp()"); - return -1; -} - -static long -frozenset_hash(PyObject *self) -{ - PySetObject *so = (PySetObject *)self; - long h, hash = 1927868237L; - setentry *entry; - int i; - - if (so->hash != -1) - return so->hash; - - hash *= set_len(self) + 1; - entry = &so->table[0]; - for (i=so->used ; i ; entry++, i--) { - while (entry->key == NULL || entry->key==dummy) - entry++; - /* Work to increase the bit dispersion for closely spaced hash - values. The is important because some use cases have many - combinations of a small number of elements with nearby - hashes so that many distinct combinations collapse to only - a handful of distinct hash values. */ - h = entry->hash; - hash ^= (h ^ (h << 16) ^ 89869747L) * 3644798167u; - } - hash = hash * 69069L + 907133923L; - if (hash == -1) - hash = 590923713L; - so->hash = hash; - return hash; -} - static PyObject * set_richcompare(PySetObject *v, PyObject *w, int op) { @@ -1502,6 +1444,48 @@ set_richcompare(PySetObject *v, PyObject *w, int op) return Py_NotImplemented; } +static int +set_nocmp(PyObject *self) +{ + PyErr_SetString(PyExc_TypeError, "cannot compare sets using cmp()"); + return -1; +} + +static long +frozenset_hash(PyObject *self) +{ + PySetObject *so = (PySetObject *)self; + long h, hash = 1927868237L; + setentry *entry; + int pos = 0; + + if (so->hash != -1) + return so->hash; + + hash *= set_len(self) + 1; + while (set_next(so, &pos, &entry)) { + /* Work to increase the bit dispersion for closely spaced hash + values. The is important because some use cases have many + combinations of a small number of elements with nearby + hashes so that many distinct combinations collapse to only + a handful of distinct hash values. */ + h = entry->hash; + hash ^= (h ^ (h << 16) ^ 89869747L) * 3644798167u; + } + hash = hash * 69069L + 907133923L; + if (hash == -1) + hash = 590923713L; + so->hash = hash; + return hash; +} + +static long +set_nohash(PyObject *self) +{ + PyErr_SetString(PyExc_TypeError, "set objects are unhashable"); + return -1; +} + static PyObject * set_repr(PySetObject *so) { |