| /* Install given floating-point environment and raise exceptions. |
| Copyright (C) 1997-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <fenv.h> |
| #include <fpu_control.h> |
| #include <arm-features.h> |
| |
| |
| int |
| __feupdateenv (const fenv_t *envp) |
| { |
| fpu_control_t fpscr, new_fpscr, updated_fpscr; |
| int excepts; |
| |
| /* Fail if a VFP unit isn't present. */ |
| if (!ARM_HAVE_VFP) |
| return 1; |
| |
| _FPU_GETCW (fpscr); |
| excepts = fpscr & FE_ALL_EXCEPT; |
| |
| if ((envp != FE_DFL_ENV) && (envp != FE_NOMASK_ENV)) |
| { |
| /* Merge current exception flags with the saved fenv. */ |
| new_fpscr = envp->__cw | excepts; |
| |
| /* Write new FPSCR if different (ignoring NZCV flags). */ |
| if (((fpscr ^ new_fpscr) & ~_FPU_MASK_NZCV) != 0) |
| _FPU_SETCW (new_fpscr); |
| |
| /* Raise the exceptions if enabled in the new FP state. */ |
| if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT)) |
| return __feraiseexcept (excepts); |
| |
| return 0; |
| } |
| |
| /* Preserve the reserved FPSCR flags. */ |
| new_fpscr = fpscr & (_FPU_RESERVED | FE_ALL_EXCEPT); |
| new_fpscr |= (envp == FE_DFL_ENV) ? _FPU_DEFAULT : _FPU_IEEE; |
| |
| if (((new_fpscr ^ fpscr) & ~_FPU_MASK_NZCV) != 0) |
| { |
| _FPU_SETCW (new_fpscr); |
| |
| /* Not all VFP architectures support trapping exceptions, so |
| test whether the relevant bits were set and fail if not. */ |
| _FPU_GETCW (updated_fpscr); |
| |
| if (new_fpscr & ~updated_fpscr) |
| return 1; |
| } |
| |
| /* Raise the exceptions if enabled in the new FP state. */ |
| if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT)) |
| return __feraiseexcept (excepts); |
| |
| return 0; |
| } |
| libm_hidden_def (__feupdateenv) |
| weak_alias (__feupdateenv, feupdateenv) |
| libm_hidden_weak (feupdateenv) |
