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/* Store current floating-point environment and clear exceptions.
Copyright (C) 2000-2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Huggins-Daines <dhd@debian.org>, 2000
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 <string.h>
int
feholdexcept (fenv_t *envp)
{
union { unsigned long long buf[4]; fenv_t env; } clear;
unsigned long long *bufptr;
/* Store the environment. */
bufptr = clear.buf;
__asm__ (
"fstd,ma %%fr0,8(%1)\n"
: "=m" (clear), "+r" (bufptr) : : "%r0");
memcpy (envp, &clear.env, sizeof (fenv_t));
/* Clear exception queues */
memset (clear.env.__exception, 0, sizeof (clear.env.__exception));
/* And set all exceptions to non-stop. */
clear.env.__status_word &= ~FE_ALL_EXCEPT;
/* Now clear all flags */
clear.env.__status_word &= ~(FE_ALL_EXCEPT << 27);
/* Load the new environment. Note: fr0 must load last to enable T-bit
Thus we start bufptr at the end and work backwards */
bufptr = (unsigned long long *)((unsigned int)(clear.buf) + sizeof(unsigned int)*4);
__asm__ (
"fldd,mb -8(%0),%%fr0\n"
: : "r" (bufptr), "m" (clear) : "%r0");
return 0;
}
libm_hidden_def (feholdexcept)
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