1 | /* Set current rounding direction. |
2 | Copyright (C) 2000-2022 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 | |
21 | int |
22 | __fesetround (int round) |
23 | { |
24 | union { unsigned long long l; unsigned int sw[2]; } s; |
25 | |
26 | if (round & ~FE_DOWNWARD) |
27 | /* round is not a valid rounding mode. */ |
28 | return 1; |
29 | |
30 | /* Get the current status word. */ |
31 | __asm__ ("fstd %%fr0,0(%1)" : "=m" (s.l) : "r" (&s.l) : "%r0" ); |
32 | s.sw[0] &= ~FE_DOWNWARD; |
33 | s.sw[0] |= round & FE_DOWNWARD; |
34 | __asm__ ("fldd 0(%0),%%fr0" : : "r" (&s.l), "m" (s.l) : "%r0" ); |
35 | |
36 | return 0; |
37 | } |
38 | |
39 | libm_hidden_def (__fesetround) |
40 | weak_alias (__fesetround, fesetround) |
41 | libm_hidden_weak (fesetround) |
42 | |