projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| e39762f9 | 1 | /* Install given floating-point environment and raise exceptions. |
| f7a9f785 | 2 | Copyright (C) 1997-2016 Free Software Foundation, Inc. |
| e39762f9 DJ |
3 | This file is part of the GNU C Library. |
| 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
| 5 | ||
| 6 | The GNU C Library is free software; you can redistribute it and/or | |
| 7 | modify it under the terms of the GNU Lesser General Public | |
| 8 | License as published by the Free Software Foundation; either | |
| 9 | version 2.1 of the License, or (at your option) any later version. | |
| 10 | ||
| 11 | The GNU C Library is distributed in the hope that it will be useful, | |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 14 | Lesser General Public License for more details. | |
| 15 | ||
| 16 | You should have received a copy of the GNU Lesser General Public | |
| ab84e3ff PE |
17 | License along with the GNU C Library. If not, see |
| 18 | <http://www.gnu.org/licenses/>. */ | |
| e39762f9 | 19 | |
| 18f8524d | 20 | #include <fenv.h> |
| a3dd035d | 21 | #include <fpu_control.h> |
| a4ca5195 | 22 | #include <arm-features.h> |
| e39762f9 | 23 | |
| e39762f9 DJ |
24 | |
| 25 | int | |
| 8116321f | 26 | __feupdateenv (const fenv_t *envp) |
| e39762f9 | 27 | { |
| db59bad3 W |
28 | fpu_control_t fpscr, new_fpscr, updated_fpscr; |
| 29 | int excepts; | |
| e39762f9 | 30 | |
| 1a2f40e5 W |
31 | /* Fail if a VFP unit isn't present. */ |
| 32 | if (!ARM_HAVE_VFP) | |
| 33 | return 1; | |
| e39762f9 | 34 | |
| 18f8524d | 35 | _FPU_GETCW (fpscr); |
| db59bad3 | 36 | excepts = fpscr & FE_ALL_EXCEPT; |
| e39762f9 | 37 | |
| db59bad3 W |
38 | if ((envp != FE_DFL_ENV) && (envp != FE_NOMASK_ENV)) |
| 39 | { | |
| 40 | /* Merge current exception flags with the saved fenv. */ | |
| 41 | new_fpscr = envp->__cw | excepts; | |
| 42 | ||
| 43 | /* Write new FPSCR if different (ignoring NZCV flags). */ | |
| 44 | if (((fpscr ^ new_fpscr) & ~_FPU_MASK_NZCV) != 0) | |
| 45 | _FPU_SETCW (new_fpscr); | |
| 46 | ||
| 47 | /* Raise the exceptions if enabled in the new FP state. */ | |
| 48 | if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT)) | |
| 0747f818 | 49 | return __feraiseexcept (excepts); |
| db59bad3 W |
50 | |
| 51 | return 0; | |
| 52 | } | |
| 53 | ||
| 54 | /* Preserve the reserved FPSCR flags. */ | |
| 55 | new_fpscr = fpscr & (_FPU_RESERVED | FE_ALL_EXCEPT); | |
| 56 | new_fpscr |= (envp == FE_DFL_ENV) ? _FPU_DEFAULT : _FPU_IEEE; | |
| 57 | ||
| 58 | if (((new_fpscr ^ fpscr) & ~_FPU_MASK_NZCV) != 0) | |
| 59 | { | |
| 60 | _FPU_SETCW (new_fpscr); | |
| 61 | ||
| 62 | /* Not all VFP architectures support trapping exceptions, so | |
| 63 | test whether the relevant bits were set and fail if not. */ | |
| 64 | _FPU_GETCW (updated_fpscr); | |
| 65 | ||
| 66 | if (new_fpscr & ~updated_fpscr) | |
| 67 | return 1; | |
| 68 | } | |
| 69 | ||
| 70 | /* Raise the exceptions if enabled in the new FP state. */ | |
| 71 | if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT)) | |
| 0747f818 | 72 | return __feraiseexcept (excepts); |
| e39762f9 | 73 | |
| 1a2f40e5 | 74 | return 0; |
| e39762f9 | 75 | } |
| 8116321f JM |
76 | libm_hidden_def (__feupdateenv) |
| 77 | weak_alias (__feupdateenv, feupdateenv) | |
| 78 | libm_hidden_weak (feupdateenv) |