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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 */
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