diff options
| -rwxr-xr-x | Lib/test/test_array.py | 6 | ||||
| -rw-r--r-- | Misc/NEWS | 2 | ||||
| -rw-r--r-- | Modules/arraymodule.c | 26 |
3 files changed, 25 insertions, 9 deletions
diff --git a/Lib/test/test_array.py b/Lib/test/test_array.py index 1cce991..b44eb97 100755 --- a/Lib/test/test_array.py +++ b/Lib/test/test_array.py @@ -504,6 +504,12 @@ class BaseTest(unittest.TestCase): array.array(self.typecode) ) + a = 5 * array.array(self.typecode, self.example[:1]) + self.assertEqual( + a, + array.array(self.typecode, [a[0]] * 5) + ) + self.assertRaises(TypeError, a.__mul__, "bad") def test_imul(self): @@ -45,6 +45,8 @@ Core and Builtins Library ------- +- Issue #1569291: Speed up array.repeat(). + - Provide an interface to set the optimization level of compilation in py_compile, compileall and zipfile.PyZipFile. diff --git a/Modules/arraymodule.c b/Modules/arraymodule.c index 18e5e66..77a162c 100644 --- a/Modules/arraymodule.c +++ b/Modules/arraymodule.c @@ -674,11 +674,9 @@ array_concat(arrayobject *a, PyObject *bb) static PyObject * array_repeat(arrayobject *a, Py_ssize_t n) { - Py_ssize_t i; Py_ssize_t size; arrayobject *np; - char *p; - Py_ssize_t nbytes; + Py_ssize_t oldbytes, newbytes; if (n < 0) n = 0; if ((Py_SIZE(a) != 0) && (n > PY_SSIZE_T_MAX / Py_SIZE(a))) { @@ -688,13 +686,23 @@ array_repeat(arrayobject *a, Py_ssize_t n) np = (arrayobject *) newarrayobject(&Arraytype, size, a->ob_descr); if (np == NULL) return NULL; - p = np->ob_item; - nbytes = Py_SIZE(a) * a->ob_descr->itemsize; - for (i = 0; i < n; i++) { - memcpy(p, a->ob_item, nbytes); - p += nbytes; + if (n == 0) + return (PyObject *)np; + oldbytes = Py_SIZE(a) * a->ob_descr->itemsize; + newbytes = oldbytes * n; + /* this follows the code in unicode_repeat */ + if (oldbytes == 1) { + memset(np->ob_item, a->ob_item[0], newbytes); + } else { + Py_ssize_t done = oldbytes; + Py_MEMCPY(np->ob_item, a->ob_item, oldbytes); + while (done < newbytes) { + Py_ssize_t ncopy = (done <= newbytes-done) ? done : newbytes-done; + Py_MEMCPY(np->ob_item+done, np->ob_item, ncopy); + done += ncopy; + } } - return (PyObject *) np; + return (PyObject *)np; } static int |