diff options
Diffstat (limited to 'REORG.TODO/sysdeps/arm/feupdateenv.c')
-rw-r--r-- | REORG.TODO/sysdeps/arm/feupdateenv.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/arm/feupdateenv.c b/REORG.TODO/sysdeps/arm/feupdateenv.c new file mode 100644 index 0000000000..21afa51d4a --- /dev/null +++ b/REORG.TODO/sysdeps/arm/feupdateenv.c @@ -0,0 +1,78 @@ +/* Install given floating-point environment and raise exceptions. + Copyright (C) 1997-2017 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) |