| /* 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_libc.h> |
| #include <fpu_control.h> |
| |
| #define _FPU_MASK_ALL (_FPU_MASK_ZM | _FPU_MASK_OM | _FPU_MASK_UM | _FPU_MASK_XM | _FPU_MASK_IM) |
| |
| int |
| __feupdateenv (const fenv_t *envp) |
| { |
| fenv_union_t old, new; |
| |
| /* Save the currently set exceptions. */ |
| new.fenv = *envp; |
| old.fenv = fegetenv_register (); |
| |
| /* Restore rounding mode and exception enable from *envp and merge |
| exceptions. Leave fraction rounded/inexact and FP result/CC bits |
| unchanged. */ |
| new.l = (old.l & 0xffffffff1fffff00LL) | (new.l & 0x1ff80fff); |
| |
| /* If the old env has no enabled exceptions and the new env has any enabled |
| exceptions, then unmask SIGFPE in the MSR FE0/FE1 bits. This will put |
| the hardware into "precise mode" and may cause the FPU to run slower on |
| some hardware. */ |
| if ((old.l & _FPU_MASK_ALL) == 0 && (new.l & _FPU_MASK_ALL) != 0) |
| (void) __fe_nomask_env_priv (); |
| |
| /* If the old env had any enabled exceptions and the new env has no enabled |
| exceptions, then mask SIGFPE in the MSR FE0/FE1 bits. This may allow the |
| FPU to run faster because it always takes the default action and can not |
| generate SIGFPE. */ |
| if ((old.l & _FPU_MASK_ALL) != 0 && (new.l & _FPU_MASK_ALL) == 0) |
| (void)__fe_mask_env (); |
| |
| /* Atomically enable and raise (if appropriate) exceptions set in `new'. */ |
| fesetenv_register (new.fenv); |
| |
| /* Success. */ |
| return 0; |
| } |
| |
| #include <shlib-compat.h> |
| #if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2) |
| strong_alias (__feupdateenv, __old_feupdateenv) |
| compat_symbol (libm, __old_feupdateenv, feupdateenv, GLIBC_2_1); |
| #endif |
| |
| libm_hidden_def (__feupdateenv) |
| libm_hidden_ver (__feupdateenv, feupdateenv) |
| versioned_symbol (libm, __feupdateenv, feupdateenv, GLIBC_2_2); |