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
23 int
__feraiseexcept(int excepts)24 __feraiseexcept (int excepts)
25 {
26 /* Raise exceptions represented by EXCEPTS. But we must raise only one
27 signal at a time. It is important that if the overflow/underflow
28 exception and the divide by zero exception are given at the same
29 time, the overflow/underflow exception follows the divide by zero
30 exception. */
31
32 /* First: invalid exception. */
33 if (excepts & FE_INVALID)
34 {
35 /* One example of an invalid operation is 0 * Infinity. */
36 double d = HUGE_VAL;
37 __asm__ __volatile__ ("fmul%.s %#0r0,%0; fnop" : "=f" (d) : "0" (d));
38 }
39
40 /* Next: division by zero. */
41 if (excepts & FE_DIVBYZERO)
42 {
43 double d = 1.0;
44 __asm__ __volatile__ ("fdiv%.s %#0r0,%0; fnop" : "=f" (d) : "0" (d));
45 }
46
47 /* Next: overflow. */
48 if (excepts & FE_OVERFLOW)
49 {
50 long double d = LDBL_MAX;
51
52 __asm__ __volatile__ ("fmul%.x %0,%0; fnop" : "=f" (d) : "0" (d));
53 }
54
55 /* Next: underflow. */
56 if (excepts & FE_UNDERFLOW)
57 {
58 long double d = -LDBL_MAX;
59
60 __asm__ __volatile__ ("fetox%.x %0; fnop" : "=f" (d) : "0" (d));
61 }
62
63 /* Last: inexact. */
64 if (excepts & FE_INEXACT)
65 {
66 long double d = 1.0;
67 __asm__ __volatile__ ("fdiv%.s %#0r3,%0; fnop" : "=f" (d) : "0" (d));
68 }
69
70 /* Success. */
71 return 0;
72 }
73
74 #include <shlib-compat.h>
75 #if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
76 strong_alias (__feraiseexcept, __old_feraiseexcept)
77 compat_symbol (libm, __old_feraiseexcept, feraiseexcept, GLIBC_2_1);
78 #endif
79
80 libm_hidden_def (__feraiseexcept)
81 libm_hidden_ver (__feraiseexcept, feraiseexcept)
82 versioned_symbol (libm, __feraiseexcept, feraiseexcept, GLIBC_2_2);
83