https://hg.python.org/cpython/rev/090c3e3a648d changeset: 99656:090c3e3a648d user: Serhiy Storchaka <storchaka@gmail.com> date: Mon Dec 21 12:57:27 2015 +0200 summary: Issue #25869: Optimized deepcopying ElementTree; it is now 20 times faster. files: Misc/NEWS | 2 + Modules/_elementtree.c | 78 ++++++++++++++++++++--------- 2 files changed, 56 insertions(+), 24 deletions(-) diff --git a/Misc/NEWS b/Misc/NEWS --- a/Misc/NEWS +++ b/Misc/NEWS @@ -115,6 +115,8 @@ Library ------- +- Issue #25869: Optimized deepcopying ElementTree; it is now 20 times faster. + - Issue #25873: Optimized iterating ElementTree. Iterating elements Element.iter() is now 40% faster, iterating text Element.itertext() is now up to 2.5 times faster. diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c --- a/Modules/_elementtree.c +++ b/Modules/_elementtree.c @@ -129,30 +129,6 @@ /* helpers */ LOCAL(PyObject*) -deepcopy(PyObject* object, PyObject* memo) -{ - /* do a deep copy of the given object */ - PyObject* args; - PyObject* result; - elementtreestate *st = ET_STATE_GLOBAL; - - if (!st->deepcopy_obj) { - PyErr_SetString( - PyExc_RuntimeError, - "deepcopy helper not found" - ); - return NULL; - } - - args = PyTuple_Pack(2, object, memo); - if (!args) - return NULL; - result = PyObject_CallObject(st->deepcopy_obj, args); - Py_DECREF(args); - return result; -} - -LOCAL(PyObject*) list_join(PyObject* list) { /* join list elements (destroying the list in the process) */ @@ -748,6 +724,9 @@ return (PyObject*) element; } +/* Helper for a deep copy. */ +LOCAL(PyObject *) deepcopy(PyObject *, PyObject *); + /*[clinic input] _elementtree.Element.__deepcopy__ @@ -838,6 +817,57 @@ return NULL; } +LOCAL(PyObject *) +deepcopy(PyObject *object, PyObject *memo) +{ + /* do a deep copy of the given object */ + PyObject *args; + PyObject *result; + elementtreestate *st; + + /* Fast paths */ + if (object == Py_None || PyUnicode_CheckExact(object)) { + Py_INCREF(object); + return object; + } + + if (Py_REFCNT(object) == 1) { + if (PyDict_CheckExact(object)) { + PyObject *key, *value; + Py_ssize_t pos = 0; + int simple = 1; + while (PyDict_Next(object, &pos, &key, &value)) { + if (!PyUnicode_CheckExact(key) || !PyUnicode_CheckExact(value)) { + simple = 0; + break; + } + } + if (simple) + return PyDict_Copy(object); + /* Fall through to general case */ + } + else if (Element_CheckExact(object)) { + return _elementtree_Element___deepcopy__((ElementObject *)object, memo); + } + } + + /* General case */ + st = ET_STATE_GLOBAL; + if (!st->deepcopy_obj) { + PyErr_SetString(PyExc_RuntimeError, + "deepcopy helper not found"); + return NULL; + } + + args = PyTuple_Pack(2, object, memo); + if (!args) + return NULL; + result = PyObject_CallObject(st->deepcopy_obj, args); + Py_DECREF(args); + return result; +} + + /*[clinic input] _elementtree.Element.__sizeof__ -> Py_ssize_t -- Repository URL: https://hg.python.org/cpython