1/* Set floating-point environment exception handling.
2 Copyright (C) 1997-2024 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_libc.h>
20
21int
22__fesetexceptflag (const fexcept_t *flagp, int excepts)
23{
24 fenv_union_t u, n;
25 fexcept_t flag;
26
27 /* Get the current state. */
28 u.fenv = fegetenv_register ();
29
30 /* Ignore exceptions not listed in 'excepts'. */
31 flag = *flagp & excepts;
32
33 /* Replace the exception status */
34 int excepts_mask = FPSCR_STICKY_BITS & excepts;
35 if ((excepts & FE_INVALID) != 0)
36 excepts_mask |= FE_ALL_INVALID;
37 n.l = ((u.l & ~excepts_mask)
38 | (flag & FPSCR_STICKY_BITS)
39 /* Turn FE_INVALID into FE_INVALID_SOFTWARE. */
40 | (flag >> ((31 - FPSCR_VX) - (31 - FPSCR_VXSOFT))
41 & FE_INVALID_SOFTWARE));
42
43 /* Store the new status word (along with the rest of the environment).
44 This may cause floating-point exceptions if the restored state
45 requests it. */
46 if (n.l != u.l)
47 {
48 if (n.l & fenv_exceptions_to_reg (excepts))
49 /* Setting the exception flags may trigger a trap. ISO C 23 ยง 7.6.4.4
50 does not allow it. */
51 return -1;
52
53 fesetenv_register (n.fenv);
54 }
55
56 /* Deal with FE_INVALID_SOFTWARE not being implemented on some chips. */
57 if (flag & FE_INVALID)
58 feraiseexcept(FE_INVALID);
59
60 /* Success. */
61 return 0;
62}
63
64#include <shlib-compat.h>
65#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
66strong_alias (__fesetexceptflag, __old_fesetexceptflag)
67compat_symbol (libm, __old_fesetexceptflag, fesetexceptflag, GLIBC_2_1);
68#endif
69
70versioned_symbol (libm, __fesetexceptflag, fesetexceptflag, GLIBC_2_2);
71

source code of glibc/sysdeps/powerpc/fpu/fsetexcptflg.c