1 /* Set floating-point environment exception handling.
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 <math.h>
21 #include <unistd.h>
22 #include <ldsodefs.h>
23 #include <dl-procinfo.h>
24
25 int
__fesetexceptflag(const fexcept_t * flagp,int excepts)26 __fesetexceptflag (const fexcept_t *flagp, int excepts)
27 {
28 fenv_t temp;
29
30 /* Get the current environment. We have to do this since we cannot
31 separately set the status word. */
32 __asm__ ("fnstenv %0" : "=m" (*&temp));
33
34 temp.__status_word &= ~(excepts & FE_ALL_EXCEPT);
35 temp.__status_word |= *flagp & excepts & FE_ALL_EXCEPT;
36
37 /* Store the new status word (along with the rest of the environment.
38 Possibly new exceptions are set but they won't get executed unless
39 the next floating-point instruction. */
40 __asm__ ("fldenv %0" : : "m" (*&temp));
41
42 /* If the CPU supports SSE, we set the MXCSR as well. */
43 if (CPU_FEATURE_USABLE (SSE))
44 {
45 unsigned int xnew_exc;
46
47 /* Get the current MXCSR. */
48 __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
49
50 /* Set the relevant bits. */
51 xnew_exc &= ~(excepts & FE_ALL_EXCEPT);
52 xnew_exc |= *flagp & excepts & FE_ALL_EXCEPT;
53
54 /* Put the new data in effect. */
55 __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
56 }
57
58 /* Success. */
59 return 0;
60 }
61
62 #include <shlib-compat.h>
63 #if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
64 strong_alias (__fesetexceptflag, __old_fesetexceptflag)
65 compat_symbol (libm, __old_fesetexceptflag, fesetexceptflag, GLIBC_2_1);
66 #endif
67
68 versioned_symbol (libm, __fesetexceptflag, fesetexceptflag, GLIBC_2_2);
69