1 /* Clear given exceptions in current floating-point environment.
2    Copyright (C) 1998-2025 Free Software Foundation, Inc.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library.  If not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <fenv.h>
19 #include "fenv_libc.h"
20 #include <fpu_control.h>
21 
22 int
feclearexcept(int excepts)23 feclearexcept (int excepts)
24 {
25   int cw;
26 
27   /* Mask out unsupported bits/exceptions.  */
28   excepts &= FE_ALL_EXCEPT;
29 
30   /* Read the complete control word.  */
31   _FPU_GETCW (cw);
32 
33   /* Clear exception flag bits and cause bits. If the cause bit is not
34      cleared, the next CTC instruction (just below) will re-generate the
35      exception.  */
36 
37   cw &= ~(excepts | (excepts << CAUSE_SHIFT));
38 
39   /* Put the new data in effect.  */
40   _FPU_SETCW (cw);
41 
42   /* Success.  */
43   return 0;
44 }
45