blob: 0bea7726af48acb138d25d8183d1db467039bd80 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
/* Compute 2^x.
Copyright (C) 2012-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
#include <float.h>
long double
__ieee754_exp2l (long double x)
{
if (__builtin_expect (isless (x, (long double) LDBL_MAX_EXP), 1))
{
if (__builtin_expect (isgreaterequal (x, (long double) (LDBL_MIN_EXP
- LDBL_MANT_DIG
- 1)), 1))
{
int intx = (int) x;
long double fractx = x - intx;
return __scalbnl (__ieee754_expl (M_LN2l * fractx), intx);
}
else
{
/* Underflow or exact zero. */
if (__isinfl (x))
return 0;
else
return LDBL_MIN * LDBL_MIN;
}
}
else
/* Infinity, NaN or overflow. */
return LDBL_MAX * x;
}
strong_alias (__ieee754_exp2l, __exp2l_finite)
|
