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/*
* Copyright (C) 2007 Free Software Foundation, Inc.
*
* This file is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2, or (at your option) any
* later version.
*
* In addition to the permissions in the GNU General Public License, the
* Free Software Foundation gives you unlimited permission to link the
* compiled version of this file with other programs, and to distribute
* those programs without any restriction coming from the use of this
* file. (The General Public License restrictions do apply in other
* respects; for example, they cover modification of the file, and
* distribution when not linked into another program.)
*
* This file 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
* As a special exception, if you link this library with files
* compiled with GCC to produce an executable, this does not cause
* the resulting executable to be covered by the GNU General Public License.
* This exception does not however invalidate any other reasons why
* the executable file might be covered by the GNU General Public License.
*/
#if __PREC == 32
#define X87CW (0 << 8) /* Single precision (24 bits) */
#elif __PREC == 64
#define X87CW (2 << 8) /* Double precision (53 bits) */
#elif __PREC == 80
#define X87CW (3 << 8) /* Extended precision (64 bits) */
#else
#error "Wrong precision requested."
#endif
#define X87CW_PCMASK (3 << 8)
static void __attribute__((constructor))
set_precision (void)
{
unsigned short int cwd;
asm volatile ("fstcw\t%0" : "=m" (cwd));
cwd &= ~X87CW_PCMASK;
cwd |= X87CW;
asm volatile ("fldcw\t%0" : : "m" (cwd));
}
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