1/* Copyright (C) 2011-2018 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#include <math-svid-compat.h>
22#include <libm-alias-double.h>
23
24
25#if LIBM_SVID_COMPAT
26/* wrapper pow */
27double
28__pow (double x, double y)
29{
30 double z = __ieee754_pow (x, y);
31 if (__glibc_unlikely (!isfinite (z)))
32 {
33 if (_LIB_VERSION != _IEEE_)
34 {
35 if (isfinite (x) && isfinite (y))
36 {
37 if (isnan (z))
38 /* pow neg**non-int */
39 return __kernel_standard (x, y, 24);
40 else if (x == 0.0 && y < 0.0)
41 {
42 if (signbit (x) && signbit (z))
43 /* pow(-0.0,negative) */
44 return __kernel_standard (x, y, 23);
45 else
46 /* pow(+0.0,negative) */
47 return __kernel_standard (x, y, 43);
48 }
49 else
50 /* pow overflow */
51 return __kernel_standard (x, y, 21);
52 }
53 }
54 }
55 else if (__builtin_expect (z == 0.0, 0)
56 && isfinite (x) && x != 0 && isfinite (y)
57 && _LIB_VERSION != _IEEE_)
58 /* pow underflow */
59 return __kernel_standard (x, y, 22);
60
61 return z;
62}
63libm_alias_double (__pow, pow)
64#endif
65