1 | /* Copyright (C) 2011-2016 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 <errno.h> |
20 | #include <math.h> |
21 | #include <math_private.h> |
22 | |
23 | |
24 | static float |
25 | __attribute__ ((noinline)) |
26 | sysv_scalbf (float x, float fn) |
27 | { |
28 | float z = __ieee754_scalbf (x, fn); |
29 | |
30 | if (__glibc_unlikely (isinf (z))) |
31 | { |
32 | if (isfinite (x)) |
33 | return __kernel_standard_f (x, fn, 132); /* scalb overflow */ |
34 | else |
35 | __set_errno (ERANGE); |
36 | } |
37 | else if (__builtin_expect (z == 0.0f, 0) && z != x) |
38 | return __kernel_standard_f (x, fn, 133); /* scalb underflow */ |
39 | |
40 | return z; |
41 | } |
42 | |
43 | |
44 | /* Wrapper scalbf */ |
45 | float |
46 | __scalbf (float x, float fn) |
47 | { |
48 | if (__glibc_unlikely (_LIB_VERSION == _SVID_)) |
49 | return sysv_scalbf (x, fn); |
50 | else |
51 | { |
52 | float z = __ieee754_scalbf (x, fn); |
53 | |
54 | if (__glibc_unlikely (!isfinite (z) || z == 0.0f)) |
55 | { |
56 | if (isnan (z)) |
57 | { |
58 | if (!isnan (x) && !isnan (fn)) |
59 | __set_errno (EDOM); |
60 | } |
61 | else if (isinf (z)) |
62 | { |
63 | if (!isinf (x) && !isinf (fn)) |
64 | __set_errno (ERANGE); |
65 | } |
66 | else |
67 | { |
68 | /* z == 0. */ |
69 | if (x != 0.0f && !isinf (fn)) |
70 | __set_errno (ERANGE); |
71 | } |
72 | } |
73 | return z; |
74 | } |
75 | } |
76 | weak_alias (__scalbf, scalbf) |
77 | |