From 0cd897450379304a221bc09fccfd8ff34bf2cf16 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Fri, 3 May 2019 12:10:38 +0300 Subject: [PATCH 1/3] Optimize sum() for bools. --- Lib/test/test_builtin.py | 16 ++++++++++++++++ Python/bltinmodule.c | 6 +++--- 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py index 5674ea89b1c408..e86a3839c78431 100644 --- a/Lib/test/test_builtin.py +++ b/Lib/test/test_builtin.py @@ -1299,6 +1299,22 @@ def test_sum(self): self.assertEqual(sum(range(10), 1000), 1045) self.assertEqual(sum(range(10), start=1000), 1045) + self.assertEqual(sum(range(10), 2**31-5), 2**31+40) + self.assertEqual(sum(range(10), 2**63-5), 2**63+40) + + self.assertEqual(sum(i % 2 != 0 for i in range(10)), 5) + self.assertEqual(sum((i % 2 != 0 for i in range(10)), 2**31-3), + 2**31+2) + self.assertEqual(sum((i % 2 != 0 for i in range(10)), 2**63-3), + 2**63+2) + + self.assertEqual(sum(i / 2 for i in range(10)), 22.5) + self.assertEqual(sum((i / 2 for i in range(10)), 1000), 1022.5) + self.assertEqual(sum((i / 2 for i in range(10)), 1000.25), 1022.75) + self.assertEqual(sum([0.5, 1]), 1.5) + self.assertEqual(sum([1, 0.5]), 1.5) + self.assertEqual(repr(sum([-0.0])), '0.0') + self.assertEqual(repr(sum([-0.0], -0.0)), '-0.0') self.assertRaises(TypeError, sum) self.assertRaises(TypeError, sum, 42) diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c index 7a2b259cbd89c8..623ff41888e210 100644 --- a/Python/bltinmodule.c +++ b/Python/bltinmodule.c @@ -2357,7 +2357,7 @@ builtin_sum_impl(PyObject *module, PyObject *iterable, PyObject *start) Assumes all inputs are the same type. If the assumption fails, default to the more general routine. */ - if (PyLong_CheckExact(result)) { + if (PyLong_CheckExact(result) || PyBool_Check(result)) { int overflow; long i_result = PyLong_AsLongAndOverflow(result, &overflow); /* If this already overflowed, don't even enter the loop. */ @@ -2373,7 +2373,7 @@ builtin_sum_impl(PyObject *module, PyObject *iterable, PyObject *start) return NULL; return PyLong_FromLong(i_result); } - if (PyLong_CheckExact(item)) { + if (PyLong_CheckExact(item) || PyBool_Check(item)) { long b = PyLong_AsLongAndOverflow(item, &overflow); long x = i_result + b; if (overflow == 0 && ((x^i_result) >= 0 || (x^b) >= 0)) { @@ -2419,7 +2419,7 @@ builtin_sum_impl(PyObject *module, PyObject *iterable, PyObject *start) Py_DECREF(item); continue; } - if (PyLong_CheckExact(item)) { + if (PyLong_Check(item)) { long value; int overflow; value = PyLong_AsLongAndOverflow(item, &overflow); From 887a0a5c1411d562710f9b7993db5e32730f813c Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Mon, 6 May 2019 09:50:09 +0300 Subject: [PATCH 2/3] Fix sum([], False). --- Lib/test/test_builtin.py | 5 +++++ Python/bltinmodule.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py index e86a3839c78431..f7d5b658b13c1a 100644 --- a/Lib/test/test_builtin.py +++ b/Lib/test/test_builtin.py @@ -1307,6 +1307,7 @@ def test_sum(self): 2**31+2) self.assertEqual(sum((i % 2 != 0 for i in range(10)), 2**63-3), 2**63+2) + self.assertIs(sum([], False), False) self.assertEqual(sum(i / 2 for i in range(10)), 22.5) self.assertEqual(sum((i / 2 for i in range(10)), 1000), 1022.5) @@ -1315,6 +1316,7 @@ def test_sum(self): self.assertEqual(sum([1, 0.5]), 1.5) self.assertEqual(repr(sum([-0.0])), '0.0') self.assertEqual(repr(sum([-0.0], -0.0)), '-0.0') + self.assertEqual(repr(sum([], -0.0)), '-0.0') self.assertRaises(TypeError, sum) self.assertRaises(TypeError, sum, 42) @@ -1326,6 +1328,9 @@ def test_sum(self): self.assertRaises(TypeError, sum, [[1], [2], [3]]) self.assertRaises(TypeError, sum, [{2:3}]) self.assertRaises(TypeError, sum, [{2:3}]*2, {2:3}) + self.assertRaises(TypeError, sum, [], '') + self.assertRaises(TypeError, sum, [], b'') + self.assertRaises(TypeError, sum, [], bytearray()) class BadSeq: def __getitem__(self, index): diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c index 3da84bdf90a80d..4f88b60deb9ade 100644 --- a/Python/bltinmodule.c +++ b/Python/bltinmodule.c @@ -2357,7 +2357,7 @@ builtin_sum_impl(PyObject *module, PyObject *iterable, PyObject *start) Assumes all inputs are the same type. If the assumption fails, default to the more general routine. */ - if (PyLong_CheckExact(result) || PyBool_Check(result)) { + if (PyLong_CheckExact(result)) { int overflow; long i_result = PyLong_AsLongAndOverflow(result, &overflow); /* If this already overflowed, don't even enter the loop. */ From cbf307d8a320ccd893a3f10b532369ab9a560e70 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Mon, 6 May 2019 09:59:43 +0300 Subject: [PATCH 3/3] Add a NEWS entry. --- .../Core and Builtins/2019-05-06-09-59-31.bpo-36781.uocWt6.rst | 1 + 1 file changed, 1 insertion(+) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2019-05-06-09-59-31.bpo-36781.uocWt6.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-05-06-09-59-31.bpo-36781.uocWt6.rst b/Misc/NEWS.d/next/Core and Builtins/2019-05-06-09-59-31.bpo-36781.uocWt6.rst new file mode 100644 index 00000000000000..2e9dcdcb9034c4 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2019-05-06-09-59-31.bpo-36781.uocWt6.rst @@ -0,0 +1 @@ +:func:`sum` has been optimized for boolean values.