Subversion Repositories openrisc_2011-10-31

/*

 * Copyright (C) 2007, 2009 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/>.

 */

#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));

}