hppa: Cleanup libm-test-ulps.
[glibc.git] / math / e_exp2l.c
blobac8ff3d7ef55ff8b25cb789d720cdd0cebc43acf
1 /* Compute 2^x.
2 Copyright (C) 2012-2013 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 #include <math.h>
20 #include <math_private.h>
21 #include <float.h>
23 long double
24 __ieee754_exp2l (long double x)
26 if (__builtin_expect (isless (x, (long double) LDBL_MAX_EXP), 1))
28 if (__builtin_expect (isgreaterequal (x, (long double) (LDBL_MIN_EXP
29 - LDBL_MANT_DIG
30 - 1)), 1))
32 int intx = (int) x;
33 long double fractx = x - intx;
34 return __scalbnl (__ieee754_expl (M_LN2l * fractx), intx);
36 else
38 /* Underflow or exact zero. */
39 if (__isinfl (x))
40 return 0;
41 else
42 return LDBL_MIN * LDBL_MIN;
45 else
46 /* Infinity, NaN or overflow. */
47 return LDBL_MAX * x;
49 strong_alias (__ieee754_exp2l, __exp2l_finite)