1 /* Store current floating-point environment and clear exceptions.
2 Copyright (C) 2001-2021 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
21 int
__feholdexcept(fenv_t * envp)22 __feholdexcept (fenv_t *envp)
23 {
24 unsigned int mxcsr;
25
26 /* Store the environment. Recall that fnstenv has a side effect of
27 masking all exceptions. Then clear all exceptions. */
28 __asm__ ("fnstenv %0\n\t"
29 "stmxcsr %1\n\t"
30 "fnclex"
31 : "=m" (*envp), "=m" (envp->__mxcsr));
32
33 /* Set the SSE MXCSR register. */
34 mxcsr = (envp->__mxcsr | 0x1f80) & ~0x3f;
35 __asm__ ("ldmxcsr %0" : : "m" (*&mxcsr));
36
37 return 0;
38 }
39 libm_hidden_def (__feholdexcept)
40 weak_alias (__feholdexcept, feholdexcept)
41 libm_hidden_weak (feholdexcept)
42