Mercurial > cpython-lru_cache-weakref
diff Python/ceval.c @ 44334:07aa19170a67 legacy-trunk
Speed-up dictionary constructor by about 10%.
New opcode, STORE_MAP saves the compiler from awkward stack manipulations
and specializes for dicts using PyDict_SetItem instead of PyObject_SetItem.
Old disassembly:
0 BUILD_MAP 0
3 DUP_TOP
4 LOAD_CONST 1 (1)
7 ROT_TWO
8 LOAD_CONST 2 ('x')
11 STORE_SUBSCR
12 DUP_TOP
13 LOAD_CONST 3 (2)
16 ROT_TWO
17 LOAD_CONST 4 ('y')
20 STORE_SUBSCR
New disassembly:
0 BUILD_MAP 0
3 LOAD_CONST 1 (1)
6 LOAD_CONST 2 ('x')
9 STORE_MAP
10 LOAD_CONST 3 (2)
13 LOAD_CONST 4 ('y')
16 STORE_MAP
| author | Raymond Hettinger <python@rcn.com> |
|---|---|
| date | Tue, 18 Dec 2007 18:26:18 +0000 |
| parents | 44c418b2bf7f |
| children | 7ac117b3be37 |
line wrap: on
line diff
--- a/Python/ceval.c Tue Dec 18 09:12:10 2007 +0000 +++ b/Python/ceval.c Tue Dec 18 18:26:18 2007 +0000 @@ -2002,6 +2002,18 @@ if (x != NULL) continue; break; + case STORE_MAP: + w = TOP(); /* key */ + u = SECOND(); /* value */ + v = THIRD(); /* dict */ + STACKADJ(-2); + assert (PyDict_CheckExact(v)); + err = PyDict_SetItem(v, w, u); /* v[w] = u */ + Py_DECREF(u); + Py_DECREF(w); + if (err == 0) continue; + break; + case LOAD_ATTR: w = GETITEM(names, oparg); v = TOP();