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/* Set current rounding direction.
Copyright (C) 1997-2017 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 <unistd.h>
#include <ldsodefs.h>
#include <dl-procinfo.h>
int
__fesetround (int round)
{
unsigned short int cw;
if ((round & ~0xc00) != 0)
/* ROUND is no valid rounding mode. */
return 1;
__asm__ ("fnstcw %0" : "=m" (*&cw));
cw &= ~0xc00;
cw |= round;
__asm__ ("fldcw %0" : : "m" (*&cw));
/* If the CPU supports SSE we set the MXCSR as well. */
if (HAS_CPU_FEATURE (SSE))
{
unsigned int xcw;
__asm__ ("stmxcsr %0" : "=m" (*&xcw));
xcw &= ~0x6000;
xcw |= round << 3;
__asm__ ("ldmxcsr %0" : : "m" (*&xcw));
}
return 0;
}
libm_hidden_def (__fesetround)
weak_alias (__fesetround, fesetround)
libm_hidden_weak (fesetround)
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