glibc/sysdeps/i386/fpu/fsetexcptflg.c
2012-02-09 23:18:22 +00:00

71 lines
2.4 KiB
C

/* Set floating-point environment exception handling.
Copyright (C) 1997,99,2000,01, 2004 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 <math.h>
#include <bp-sym.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <dl-procinfo.h>
int
__fesetexceptflag (const fexcept_t *flagp, int excepts)
{
fenv_t temp;
/* Get the current environment. We have to do this since we cannot
separately set the status word. */
__asm__ ("fnstenv %0" : "=m" (*&temp));
temp.__status_word &= ~(excepts & FE_ALL_EXCEPT);
temp.__status_word |= *flagp & excepts & FE_ALL_EXCEPT;
/* Store the new status word (along with the rest of the environment.
Possibly new exceptions are set but they won't get executed unless
the next floating-point instruction. */
__asm__ ("fldenv %0" : : "m" (*&temp));
/* If the CPU supports SSE, we set the MXCSR as well. */
if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
{
unsigned int xnew_exc;
/* Get the current MXCSR. */
__asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
/* Set the relevant bits. */
xnew_exc &= ~(excepts & FE_ALL_EXCEPT);
xnew_exc |= *flagp & excepts & FE_ALL_EXCEPT;
/* Put the new data in effect. */
__asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
}
/* Success. */
return 0;
}
#include <shlib-compat.h>
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
strong_alias (__fesetexceptflag, __old_fesetexceptflag)
compat_symbol (libm, BP_SYM (__old_fesetexceptflag), BP_SYM (fesetexceptflag), GLIBC_2_1);
#endif
versioned_symbol (libm, BP_SYM (__fesetexceptflag), BP_SYM (fesetexceptflag), GLIBC_2_2);