50 lines
1.5 KiB
C
50 lines
1.5 KiB
C
/*
|
|
* Copyright (C) 2007-2017 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 3, or (at your option) any
|
|
* later version.
|
|
*
|
|
* 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.
|
|
*
|
|
* Under Section 7 of GPL version 3, you are granted additional
|
|
* permissions described in the GCC Runtime Library Exception, version
|
|
* 3.1, as published by the Free Software Foundation.
|
|
*
|
|
* You should have received a copy of the GNU General Public License and
|
|
* a copy of the GCC Runtime Library Exception along with this program;
|
|
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
* <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef _SOFT_FLOAT
|
|
#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));
|
|
}
|
|
#endif
|