freebsd-skq/sys/i386/include/ieeefp.h
marcel b2cf4b9bc0 o Move the contents of <machine/floatingpoint.h> over to
<machine/ieeefp.h> where it belongs.
o  Remove the i386 specific inclusion of <machine/floatingpoint.h>
   from <ieeefp.h>, now that including <machine/ieeefp.h> is enough
   for all architectures.
o  Allow <machine/ieeefp.h> to inline the functions exposed by the
   headers by checking for _IEEEFP_INLINED_ in the MI header. When
   defined, prototypes are not given and it is assumed that the MD
   headers, when inlining only a subset of the functions provide
   prototypes for the functions not being inlined.

Based on patch from: Terry Lambert <tlambert2@mindspring.com>
Tested with: make release.
2003-01-19 06:01:33 +00:00

182 lines
5.5 KiB
C

/*-
* Copyright (c) 1990 Andrew Moore, Talke Studio
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#) ieeefp.h 1.0 (Berkeley) 9/23/93
* $FreeBSD$
*/
/*
* IEEE floating point type and constant definitions.
*/
#ifndef _MACHINE_IEEEFP_H_
#define _MACHINE_IEEEFP_H_
/*
* FP rounding modes
*/
typedef enum {
FP_RN=0, /* round to nearest */
FP_RM, /* round down to minus infinity */
FP_RP, /* round up to plus infinity */
FP_RZ /* truncate */
} fp_rnd_t;
/*
* FP precision modes
*/
typedef enum {
FP_PS=0, /* 24 bit (single-precision) */
FP_PRS, /* reserved */
FP_PD, /* 53 bit (double-precision) */
FP_PE /* 64 bit (extended-precision) */
} fp_prec_t;
#define fp_except_t int
/*
* FP exception masks
*/
#define FP_X_INV 0x01 /* invalid operation */
#define FP_X_DNML 0x02 /* denormal */
#define FP_X_DZ 0x04 /* zero divide */
#define FP_X_OFL 0x08 /* overflow */
#define FP_X_UFL 0x10 /* underflow */
#define FP_X_IMP 0x20 /* (im)precision */
#define FP_X_STK 0x40 /* stack fault */
/*
* FP registers
*/
#define FP_MSKS_REG 0 /* exception masks */
#define FP_PRC_REG 0 /* precision */
#define FP_RND_REG 0 /* direction */
#define FP_STKY_REG 1 /* sticky flags */
/*
* FP register bit field masks
*/
#define FP_MSKS_FLD 0x3f /* exception masks field */
#define FP_PRC_FLD 0x300 /* precision control field */
#define FP_RND_FLD 0xc00 /* round control field */
#define FP_STKY_FLD 0x3f /* sticky flags field */
/*
* FP register bit field offsets
*/
#define FP_MSKS_OFF 0 /* exception masks offset */
#define FP_PRC_OFF 8 /* precision control offset */
#define FP_RND_OFF 10 /* round control offset */
#define FP_STKY_OFF 0 /* sticky flags offset */
#ifdef __GNUC__
#define __fldenv(addr) __asm __volatile("fldenv %0" : : "m" (*(addr)))
#define __fnstenv(addr) __asm __volatile("fnstenv %0" : "=m" (*(addr)))
#define __fnstcw(addr) __asm __volatile("fnstcw %0" : "=m" (*(addr)))
#define __fnstsw(addr) __asm __volatile("fnstsw %0" : "=m" (*(addr)))
/*
* return the contents of a FP register
*/
static __inline__ int
__fpgetreg(int _reg)
{
unsigned short _mem;
/*-
* This is more efficient than it looks. The switch gets optimized
* away if _reg is constant.
*
* The default case only supports _reg == 0. We could handle more
* registers (e.g., tags) using fnstenv, but the interface doesn't
* support more.
*/
switch(_reg) {
default:
__fnstcw(&_mem);
break;
case FP_STKY_REG:
__fnstsw(&_mem);
break;
}
return _mem;
}
/*
* set a FP mode; return previous mode
*/
static __inline__ int
__fpsetreg(int _m, int _reg, int _fld, int _off)
{
unsigned _env[7];
unsigned _p;
/*
* _reg == 0 could be handled better using fnstcw/fldcw.
*/
__fnstenv(_env);
_p = (_env[_reg] & _fld) >> _off;
_env[_reg] = (_env[_reg] & ~_fld) | (_m << _off & _fld);
__fldenv(_env);
return _p;
}
#endif /* __GNUC__ */
/*
* SysV/386 FP control interface
*/
#define fpgetround() ((fp_rnd_t) \
((__fpgetreg(FP_RND_REG) & FP_RND_FLD) >> FP_RND_OFF))
#define fpsetround(m) ((fp_rnd_t) \
__fpsetreg((m), FP_RND_REG, FP_RND_FLD, FP_RND_OFF))
#define fpgetprec() ((fp_prec_t) \
((__fpgetreg(FP_PRC_REG) & FP_PRC_FLD) >> FP_PRC_OFF))
#define fpsetprec(m) ((fp_prec_t) \
__fpsetreg((m), FP_PRC_REG, FP_PRC_FLD, FP_PRC_OFF))
#define fpgetmask() ((fp_except_t) \
((~__fpgetreg(FP_MSKS_REG) & FP_MSKS_FLD) >> FP_MSKS_OFF))
#define fpsetmask(m) ((fp_except_t) \
(~__fpsetreg(~(m), FP_MSKS_REG, FP_MSKS_FLD, FP_MSKS_OFF)) & \
(FP_MSKS_FLD >> FP_MSKS_OFF))
#define fpgetsticky() ((fp_except_t) \
((__fpgetreg(FP_STKY_REG) & FP_STKY_FLD) >> FP_STKY_OFF))
#define fpresetsticky(m) ((fp_except_t) \
__fpsetreg(0, FP_STKY_REG, (m), FP_STKY_OFF))
#define fpsetsticky(m) fpresetsticky(m)
/* Suppress prototypes in the MI header. */
#define _IEEEFP_INLINED_ 1
#endif /* !_MACHINE_IEEEFP_H_ */