glibc/sysdeps/powerpc/fpu/fesetenv.c
2013-02-14 13:12:02 +00:00

61 lines
2.2 KiB
C

/* Install given floating-point environment.
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
__fesetenv (const fenv_t *envp)
{
fenv_union_t old, new;
/* get the currently set exceptions. */
new.fenv = *envp;
old.fenv = fegetenv_register ();
/* 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[1] & _FPU_MASK_ALL) == 0 && (new.l[1] & _FPU_MASK_ALL) != 0)
(void)__fe_nomask_env ();
/* 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[1] & _FPU_MASK_ALL) != 0 && (new.l[1] & _FPU_MASK_ALL) == 0)
(void)__fe_mask_env ();
fesetenv_register (*envp);
/* Success. */
return 0;
}
#include <shlib-compat.h>
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
strong_alias (__fesetenv, __old_fesetenv)
compat_symbol (libm, __old_fesetenv, fesetenv, GLIBC_2_1);
#endif
libm_hidden_ver (__fesetenv, fesetenv)
versioned_symbol (libm, __fesetenv, fesetenv, GLIBC_2_2);