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Code Issues Releases Activity

Don't provide bogus source operands in some asms. This probably shouldn't

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matter, but similar bogusness in npx.c causes compiling without -O to fail.

Use __volatile in all asms.

Parenthesize macro args.

Change the names of the macros to avoid namespace pollution.

Remove unnecessary "#ifdef __i386__".

Sort #defines.

Add comments.
This commit is contained in:
Bruce Evans 1994-09-20 22:26:37 +00:00
parent f89971dfe7
commit 8793135f2d
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=2941
2 changed files with 60 additions and 36 deletions
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48
sys/amd64/include/floatingpoint.h
View File

@ -31,28 +31,31 @@
* SUCH DAMAGE.
*
* from: @(#) floatingpoint.h 1.0 (Berkeley) 9/23/93
* $Id: floatingpoint.h,v 1.4 1993/11/07 17:42:55 wollman Exp $
*/
/*
* IEEE floating point structure and function definitions
* $Id: floatingpoint.h,v 1.5 1994/08/04 19:16:36 wollman Exp $
*/
#ifndef _FLOATINGPOINT_H_
#define _FLOATINGPOINT_H_
/*
* IEEE floating point structure and function definitions
*/
/*-
* XXX the following undocumented pollution is exported:
* fpsetsticky().
* FP*FLD, FP*OFF and FP*REG from <machine/ieeefp.h>
*/
#include <sys/cdefs.h>
#include <machine/ieeefp.h>
#ifdef __GNUC__
#ifdef __i386__
#define fnstcw(addr) __asm("fnstcw %0" : "=m" (*addr) : "0" (*addr))
#define fnstsw(addr) __asm("fnstsw %0" : "=m" (*addr) : "0" (*addr))
#define fnstenv(addr) __asm("fnstenv %0" : "=m" (*addr) : "0" (*addr))
#define fldenv(addr) __asm("fldenv %0" : : "m" (*addr))
#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
@ -62,12 +65,20 @@ __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);
__fnstcw(&_mem);
break;
case FP_STKY_REG:
fnstsw(&_mem);
__fnstsw(&_mem);
break;
}
return _mem;
@ -82,15 +93,16 @@ __fpsetreg(int _m, int _reg, int _fld, int _off)
unsigned _env[7];
unsigned _p;
fnstenv(_env);
/*
* _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);
__fldenv(_env);
return _p;
}
#endif /* __i386__ */
#endif /* __GNUC__ */
/*

48
sys/i386/include/floatingpoint.h
View File

@ -31,28 +31,31 @@
* SUCH DAMAGE.
*
* from: @(#) floatingpoint.h 1.0 (Berkeley) 9/23/93
* $Id: floatingpoint.h,v 1.4 1993/11/07 17:42:55 wollman Exp $
*/
/*
* IEEE floating point structure and function definitions
* $Id: floatingpoint.h,v 1.5 1994/08/04 19:16:36 wollman Exp $
*/
#ifndef _FLOATINGPOINT_H_
#define _FLOATINGPOINT_H_
/*
* IEEE floating point structure and function definitions
*/
/*-
* XXX the following undocumented pollution is exported:
* fpsetsticky().
* FP*FLD, FP*OFF and FP*REG from <machine/ieeefp.h>
*/
#include <sys/cdefs.h>
#include <machine/ieeefp.h>
#ifdef __GNUC__
#ifdef __i386__
#define fnstcw(addr) __asm("fnstcw %0" : "=m" (*addr) : "0" (*addr))
#define fnstsw(addr) __asm("fnstsw %0" : "=m" (*addr) : "0" (*addr))
#define fnstenv(addr) __asm("fnstenv %0" : "=m" (*addr) : "0" (*addr))
#define fldenv(addr) __asm("fldenv %0" : : "m" (*addr))
#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
@ -62,12 +65,20 @@ __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);
__fnstcw(&_mem);
break;
case FP_STKY_REG:
fnstsw(&_mem);
__fnstsw(&_mem);
break;
}
return _mem;
@ -82,15 +93,16 @@ __fpsetreg(int _m, int _reg, int _fld, int _off)
unsigned _env[7];
unsigned _p;
fnstenv(_env);
/*
* _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);
__fldenv(_env);
return _p;
}
#endif /* __i386__ */
#endif /* __GNUC__ */
/*