1/* Copyright (C) 2011-2017 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
4
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.
9
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.
14
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/>. */
18
19#include <math.h>
20#include <math_private.h>
21
22
23/* wrapper pow */
24double
25__pow (double x, double y)
26{
27 double z = __ieee754_pow (x, y);
28 if (__glibc_unlikely (!isfinite (z)))
29 {
30 if (_LIB_VERSION != _IEEE_)
31 {
32 if (isfinite (x) && isfinite (y))
33 {
34 if (isnan (z))
35 /* pow neg**non-int */
36 return __kernel_standard (x, y, 24);
37 else if (x == 0.0 && y < 0.0)
38 {
39 if (signbit (x) && signbit (z))
40 /* pow(-0.0,negative) */
41 return __kernel_standard (x, y, 23);
42 else
43 /* pow(+0.0,negative) */
44 return __kernel_standard (x, y, 43);
45 }
46 else
47 /* pow overflow */
48 return __kernel_standard (x, y, 21);
49 }
50 }
51 }
52 else if (__builtin_expect (z == 0.0, 0)
53 && isfinite (x) && x != 0 && isfinite (y)
54 && _LIB_VERSION != _IEEE_)
55 /* pow underflow */
56 return __kernel_standard (x, y, 22);
57
58 return z;
59}
60weak_alias (__pow, pow)
61#ifdef NO_LONG_DOUBLE
62strong_alias (__pow, __powl)
63weak_alias (__pow, powl)
64#endif
65