glibc/sysdeps/powerpc/fpu/feholdexcpt.c
2013-01-07 11:20:53 -06:00

48 lines
1.7 KiB
C

/* Store current floating-point environment and clear exceptions.
Copyright (C) 1997-2013 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[1] = old.l[1] & 7;
new.l[0] = old.l[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[1] & _FPU_MASK_ALL) != 0)
(void)__fe_mask_env ();
/* Put the new state in effect. */
fesetenv_register (new.fenv);
return 0;
}
libm_hidden_def (feholdexcept)