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/* FPU control word definitions.  PowerPC version.
   Copyright (C) 1996, 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#ifndef _FPU_CONTROL_H
#define _FPU_CONTROL_H

/* rounding control */
#define _FPU_RC_NEAREST 0x00   /* RECOMMENDED */
#define _FPU_RC_DOWN    0x03
#define _FPU_RC_UP      0x02
#define _FPU_RC_ZERO    0x01

#define _FPU_MASK_NI  0x04 /* non-ieee mode */

/* masking of interrupts */
#define _FPU_MASK_ZM  0x10 /* zero divide */
#define _FPU_MASK_OM  0x40 /* overflow */
#define _FPU_MASK_UM  0x20 /* underflow */
#define _FPU_MASK_XM  0x08 /* inexact */
#define _FPU_MASK_IM  0x80 /* invalid operation */

#define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */

/* The fdlibm code requires no interrupts for exceptions.  */
#define _FPU_DEFAULT  0x00000000 /* Default value.  */

/* IEEE:  same as above, but (some) exceptions;
   we leave the 'inexact' exception off.
 */
#define _FPU_IEEE     0x000000f0

/* Type of the control word.  */
typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));

/* Macros for accessing the hardware control word.  */
#define _FPU_GETCW(cw) ( { \
  fpu_control_t tmp[2] __attribute__ ((__aligned__(8))); \
  __asm__ ("mffs 0; stfd 0,%0" : "=m" (*tmp) : : "fr0"); \
  (cw)=tmp[1]; \
  tmp[1]; } )
#define _FPU_SETCW(cw) { \
  fpu_control_t tmp[2] __attribute__ ((__aligned__(8))); \
  tmp[0] = 0xFFF80000; /* More-or-less arbitrary; this is a QNaN. */ \
  tmp[1] = cw; \
  __asm__ ("lfd 0,%0; mtfsf 255,0" : : "m" (*tmp) : "fr0"); \
}

/* Default control word set at startup.  */
extern fpu_control_t __fpu_control;

__BEGIN_DECLS

/* Called at startup.  It can be used to manipulate fpu control register.  */
extern void __setfpucw __P ((fpu_control_t));

__END_DECLS

#endif /* _FPU_CONTROL_H */