1 /* Raise given exceptions.
2 Copyright (C) 1997-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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 <https://www.gnu.org/licenses/>. */
18
19 #include <fenv.h>
20 #include <float.h>
21 #include <math.h>
22 #include <shlib-compat.h>
23
24 int
__feraiseexcept(int excepts)25 __feraiseexcept (int excepts)
26 {
27 static const struct {
28 double zero, one, max, min, pi;
29 } c = {
30 0.0, 1.0, DBL_MAX, DBL_MIN, M_PI
31 };
32 double d;
33
34 /* Raise exceptions represented by EXPECTS. But we must raise only
35 one signal at a time. It is important the if the overflow/underflow
36 exception and the inexact exception are given at the same time,
37 the overflow/underflow exception follows the inexact exception. */
38
39 /* First: invalid exception. */
40 if ((FE_INVALID & excepts) != 0)
41 {
42 /* One example of an invalid operation is 0/0. */
43 __asm ("" : "=e" (d) : "0" (c.zero));
44 d /= c.zero;
45 __asm __volatile ("" : : "e" (d));
46 }
47
48 /* Next: division by zero. */
49 if ((FE_DIVBYZERO & excepts) != 0)
50 {
51 __asm ("" : "=e" (d) : "0" (c.one));
52 d /= c.zero;
53 __asm __volatile ("" : : "e" (d));
54 }
55
56 /* Next: overflow. */
57 if ((FE_OVERFLOW & excepts) != 0)
58 {
59 __asm ("" : "=e" (d) : "0" (c.max));
60 d *= d;
61 __asm __volatile ("" : : "e" (d));
62 }
63
64 /* Next: underflow. */
65 if ((FE_UNDERFLOW & excepts) != 0)
66 {
67 __asm ("" : "=e" (d) : "0" (c.min));
68 d *= d;
69 __asm __volatile ("" : : "e" (d));
70 }
71
72 /* Last: inexact. */
73 if ((FE_INEXACT & excepts) != 0)
74 {
75 __asm ("" : "=e" (d) : "0" (c.one));
76 d /= c.pi;
77 __asm __volatile ("" : : "e" (d));
78 }
79
80 /* Success. */
81 return 0;
82 }
83
84 #if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
85 strong_alias (__feraiseexcept, __old_feraiseexcept)
86 compat_symbol (libm, __old_feraiseexcept, feraiseexcept, GLIBC_2_1);
87 #endif
88
89 libm_hidden_def (__feraiseexcept)
90 libm_hidden_ver (__feraiseexcept, feraiseexcept)
91 versioned_symbol (libm, __feraiseexcept, feraiseexcept, GLIBC_2_2);
92