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/* Install given floating-point environment.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>, 1997
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <fenv.h>
void
fesetenv (const fenv_t *envp)
{
unsigned long fpcr;
fenv_t env;
/* Magic encoding of default values: high bit set (never possible for a
user-space address) is not indirect. And we don't even have to get
rid of it since we mask things around just below. */
if ((long)envp >= 0)
env = *envp;
else
env = (unsigned long)envp;
/* Reset the rounding mode with the hardware fpcr. Note that the following
system call is an implied trap barrier for our modification. */
__asm__ __volatile__("excb; mf_fpcr %0" : "=f"(fpcr));
fpcr = (fpcr & ~(3UL << 58)) | (env & (3UL << 58));
__asm__ __volatile__("mt_fpcr %0" : : "f"(fpcr));
/* Reset the exception status and mask with the kernel's FP code. */
__ieee_set_fp_control(env & (FE_ALL_EXCEPT | 0x3e));
}
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