1 | /* Copyright (C) 2001-2024 Free Software Foundation, Inc. |
2 | |
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 License as |
7 | published by the Free Software Foundation; either version 2.1 of the |
8 | 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 <fpu_control.h> |
21 | |
22 | int |
23 | feenableexcept (int excepts) |
24 | { |
25 | fpu_control_t fpcr; |
26 | fpu_control_t fpcr_new; |
27 | fpu_control_t updated_fpcr; |
28 | |
29 | _FPU_GETCW (fpcr); |
30 | excepts &= FE_ALL_EXCEPT; |
31 | fpcr_new = fpcr | (excepts << FE_EXCEPT_SHIFT); |
32 | |
33 | if (fpcr != fpcr_new) |
34 | { |
35 | _FPU_SETCW (fpcr_new); |
36 | |
37 | /* Trapping exceptions are optional in AArch64; the relevant enable |
38 | bits in FPCR are RES0 hence the absence of support can be detected |
39 | by reading back the FPCR and comparing with the required value. */ |
40 | _FPU_GETCW (updated_fpcr); |
41 | |
42 | if (fpcr_new & ~updated_fpcr) |
43 | return -1; |
44 | } |
45 | |
46 | return (fpcr >> FE_EXCEPT_SHIFT) & FE_ALL_EXCEPT; |
47 | } |
48 | |