mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-12 06:10:10 +00:00
52 lines
1.7 KiB
C
52 lines
1.7 KiB
C
/* Store current floating-point environment and clear exceptions.
|
|
Copyright (C) 1997-2017 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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
|
|
__feholdexcept (fenv_t *envp)
|
|
{
|
|
fenv_union_t old, new;
|
|
|
|
/* Save the currently set exceptions. */
|
|
old.fenv = *envp = fegetenv_register ();
|
|
|
|
/* Clear everything except for the rounding modes and non-IEEE arithmetic
|
|
flag. */
|
|
new.l = old.l & 0xffffffff00000007LL;
|
|
|
|
if (new.l == old.l)
|
|
return 0;
|
|
|
|
/* If the old env had any 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)
|
|
(void)__fe_mask_env ();
|
|
|
|
/* Put the new state in effect. */
|
|
fesetenv_register (new.fenv);
|
|
|
|
return 0;
|
|
}
|
|
libm_hidden_def (__feholdexcept)
|
|
weak_alias (__feholdexcept, feholdexcept)
|
|
libm_hidden_weak (feholdexcept)
|