1 | /* Copyright (C) 1997-2022 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 | __fesetenv (const fenv_t *envp) |
24 | { |
25 | fpu_control_t fpcr; |
26 | fpu_control_t fpcr_new; |
27 | fpu_control_t updated_fpcr; |
28 | fpu_fpsr_t fpsr; |
29 | fpu_fpsr_t fpsr_new; |
30 | |
31 | _FPU_GETCW (fpcr); |
32 | |
33 | if ((envp != FE_DFL_ENV) && (envp != FE_NOMASK_ENV)) |
34 | { |
35 | /* The new FPCR/FPSR are valid, so don't merge the reserved flags. */ |
36 | fpcr_new = envp->__fpcr; |
37 | |
38 | if (fpcr != fpcr_new) |
39 | _FPU_SETCW (fpcr_new); |
40 | |
41 | _FPU_SETFPSR (envp->__fpsr); |
42 | return 0; |
43 | } |
44 | |
45 | _FPU_GETFPSR (fpsr); |
46 | fpcr_new = fpcr & _FPU_RESERVED; |
47 | fpsr_new = fpsr & _FPU_FPSR_RESERVED; |
48 | |
49 | if (envp == FE_DFL_ENV) |
50 | { |
51 | fpcr_new |= _FPU_DEFAULT; |
52 | fpsr_new |= _FPU_FPSR_DEFAULT; |
53 | } |
54 | else |
55 | { |
56 | fpcr_new |= _FPU_FPCR_IEEE; |
57 | fpsr_new |= _FPU_FPSR_IEEE; |
58 | } |
59 | |
60 | _FPU_SETFPSR (fpsr_new); |
61 | |
62 | if (fpcr != fpcr_new) |
63 | { |
64 | _FPU_SETCW (fpcr_new); |
65 | |
66 | /* Trapping exceptions are optional in AArch64; the relevant enable |
67 | bits in FPCR are RES0 hence the absence of support can be detected |
68 | by reading back the FPCR and comparing with the required value. */ |
69 | _FPU_GETCW (updated_fpcr); |
70 | |
71 | return fpcr_new & ~updated_fpcr; |
72 | } |
73 | |
74 | return 0; |
75 | } |
76 | libm_hidden_def (__fesetenv) |
77 | weak_alias (__fesetenv, fesetenv) |
78 | libm_hidden_weak (fesetenv) |
79 |