bpo-38639: Optimize floor(), ceil() and trunc() for floats. (GH-16991)

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Serhiy Storchaka 2019-11-16 18:00:57 +02:00 committed by GitHub
parent 51edf8aaa2
commit 5fd5cb8d85
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3 changed files with 70 additions and 41 deletions

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@ -240,6 +240,13 @@ def result_check(expected, got, ulp_tol=5, abs_tol=0.0):
else:
return None
class FloatLike:
def __init__(self, value):
self.value = value
def __float__(self):
return self.value
class IntSubclass(int):
pass
@ -397,12 +404,14 @@ class MathTests(unittest.TestCase):
def testCeil(self):
self.assertRaises(TypeError, math.ceil)
self.assertEqual(int, type(math.ceil(0.5)))
self.ftest('ceil(0.5)', math.ceil(0.5), 1)
self.ftest('ceil(1.0)', math.ceil(1.0), 1)
self.ftest('ceil(1.5)', math.ceil(1.5), 2)
self.ftest('ceil(-0.5)', math.ceil(-0.5), 0)
self.ftest('ceil(-1.0)', math.ceil(-1.0), -1)
self.ftest('ceil(-1.5)', math.ceil(-1.5), -1)
self.assertEqual(math.ceil(0.5), 1)
self.assertEqual(math.ceil(1.0), 1)
self.assertEqual(math.ceil(1.5), 2)
self.assertEqual(math.ceil(-0.5), 0)
self.assertEqual(math.ceil(-1.0), -1)
self.assertEqual(math.ceil(-1.5), -1)
self.assertEqual(math.ceil(0.0), 0)
self.assertEqual(math.ceil(-0.0), 0)
#self.assertEqual(math.ceil(INF), INF)
#self.assertEqual(math.ceil(NINF), NINF)
#self.assertTrue(math.isnan(math.ceil(NAN)))
@ -410,9 +419,14 @@ class MathTests(unittest.TestCase):
class TestCeil:
def __ceil__(self):
return 42
class FloatCeil(float):
def __ceil__(self):
return 42
class TestNoCeil:
pass
self.ftest('ceil(TestCeil())', math.ceil(TestCeil()), 42)
self.assertEqual(math.ceil(TestCeil()), 42)
self.assertEqual(math.ceil(FloatCeil()), 42)
self.assertEqual(math.ceil(FloatLike(42.5)), 43)
self.assertRaises(TypeError, math.ceil, TestNoCeil())
t = TestNoCeil()
@ -536,16 +550,12 @@ class MathTests(unittest.TestCase):
def testFloor(self):
self.assertRaises(TypeError, math.floor)
self.assertEqual(int, type(math.floor(0.5)))
self.ftest('floor(0.5)', math.floor(0.5), 0)
self.ftest('floor(1.0)', math.floor(1.0), 1)
self.ftest('floor(1.5)', math.floor(1.5), 1)
self.ftest('floor(-0.5)', math.floor(-0.5), -1)
self.ftest('floor(-1.0)', math.floor(-1.0), -1)
self.ftest('floor(-1.5)', math.floor(-1.5), -2)
# pow() relies on floor() to check for integers
# This fails on some platforms - so check it here
self.ftest('floor(1.23e167)', math.floor(1.23e167), 1.23e167)
self.ftest('floor(-1.23e167)', math.floor(-1.23e167), -1.23e167)
self.assertEqual(math.floor(0.5), 0)
self.assertEqual(math.floor(1.0), 1)
self.assertEqual(math.floor(1.5), 1)
self.assertEqual(math.floor(-0.5), -1)
self.assertEqual(math.floor(-1.0), -1)
self.assertEqual(math.floor(-1.5), -2)
#self.assertEqual(math.ceil(INF), INF)
#self.assertEqual(math.ceil(NINF), NINF)
#self.assertTrue(math.isnan(math.floor(NAN)))
@ -553,9 +563,14 @@ class MathTests(unittest.TestCase):
class TestFloor:
def __floor__(self):
return 42
class FloatFloor(float):
def __floor__(self):
return 42
class TestNoFloor:
pass
self.ftest('floor(TestFloor())', math.floor(TestFloor()), 42)
self.assertEqual(math.floor(TestFloor()), 42)
self.assertEqual(math.floor(FloatFloor()), 42)
self.assertEqual(math.floor(FloatLike(41.9)), 41)
self.assertRaises(TypeError, math.floor, TestNoFloor())
t = TestNoFloor()
@ -1448,17 +1463,21 @@ class MathTests(unittest.TestCase):
self.assertEqual(math.trunc(-0.999999), -0)
self.assertEqual(math.trunc(-100.999), -100)
class TestTrunc(object):
class TestTrunc:
def __trunc__(self):
return 23
class TestNoTrunc(object):
class FloatTrunc(float):
def __trunc__(self):
return 23
class TestNoTrunc:
pass
self.assertEqual(math.trunc(TestTrunc()), 23)
self.assertEqual(math.trunc(FloatTrunc()), 23)
self.assertRaises(TypeError, math.trunc)
self.assertRaises(TypeError, math.trunc, 1, 2)
self.assertRaises(TypeError, math.trunc, FloatLike(23.5))
self.assertRaises(TypeError, math.trunc, TestNoTrunc())
def testIsfinite(self):

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@ -0,0 +1,2 @@
Optimized :func:`math.floor()`, :func:`math.ceil()` and :func:`math.trunc()`
for floats.

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@ -1013,12 +1013,6 @@ math_1(PyObject *arg, double (*func) (double), int can_overflow)
return math_1_to_whatever(arg, func, PyFloat_FromDouble, can_overflow);
}
static PyObject *
math_1_to_int(PyObject *arg, double (*func) (double), int can_overflow)
{
return math_1_to_whatever(arg, func, PyLong_FromDouble, can_overflow);
}
static PyObject *
math_2(PyObject *const *args, Py_ssize_t nargs,
double (*func) (double, double), const char *funcname)
@ -1112,17 +1106,22 @@ math_ceil(PyObject *module, PyObject *number)
/*[clinic end generated code: output=6c3b8a78bc201c67 input=2725352806399cab]*/
{
_Py_IDENTIFIER(__ceil__);
PyObject *method, *result;
method = _PyObject_LookupSpecial(number, &PyId___ceil__);
if (method == NULL) {
if (!PyFloat_CheckExact(number)) {
PyObject *method = _PyObject_LookupSpecial(number, &PyId___ceil__);
if (method != NULL) {
PyObject *result = _PyObject_CallNoArg(method);
Py_DECREF(method);
return result;
}
if (PyErr_Occurred())
return NULL;
return math_1_to_int(number, ceil, 0);
}
result = _PyObject_CallNoArg(method);
Py_DECREF(method);
return result;
double x = PyFloat_AsDouble(number);
if (x == -1.0 && PyErr_Occurred())
return NULL;
return PyLong_FromDouble(ceil(x));
}
FUNC2(copysign, copysign,
@ -1170,17 +1169,22 @@ math_floor(PyObject *module, PyObject *number)
/*[clinic end generated code: output=c6a65c4884884b8a input=63af6b5d7ebcc3d6]*/
{
_Py_IDENTIFIER(__floor__);
PyObject *method, *result;
method = _PyObject_LookupSpecial(number, &PyId___floor__);
if (method == NULL) {
if (!PyFloat_CheckExact(number)) {
PyObject *method = _PyObject_LookupSpecial(number, &PyId___floor__);
if (method != NULL) {
PyObject *result = _PyObject_CallNoArg(method);
Py_DECREF(method);
return result;
}
if (PyErr_Occurred())
return NULL;
return math_1_to_int(number, floor, 0);
}
result = _PyObject_CallNoArg(method);
Py_DECREF(method);
return result;
double x = PyFloat_AsDouble(number);
if (x == -1.0 && PyErr_Occurred())
return NULL;
return PyLong_FromDouble(floor(x));
}
FUNC1A(gamma, m_tgamma,
@ -2061,6 +2065,10 @@ math_trunc(PyObject *module, PyObject *x)
_Py_IDENTIFIER(__trunc__);
PyObject *trunc, *result;
if (PyFloat_CheckExact(x)) {
return PyFloat_Type.tp_as_number->nb_int(x);
}
if (Py_TYPE(x)->tp_dict == NULL) {
if (PyType_Ready(Py_TYPE(x)) < 0)
return NULL;