floatingpoint.h revision 719
1326Salm/*- 2326Salm * Copyright (c) 1993 Andrew Moore, Talke Studio 3326Salm * All rights reserved. 4326Salm * 5326Salm * Redistribution and use in source and binary forms, with or without 6326Salm * modification, are permitted provided that the following conditions 7326Salm * are met: 8326Salm * 1. Redistributions of source code must retain the above copyright 9326Salm * notice, this list of conditions and the following disclaimer. 10326Salm * 2. Redistributions in binary form must reproduce the above copyright 11326Salm * notice, this list of conditions and the following disclaimer in the 12326Salm * documentation and/or other materials provided with the distribution. 13326Salm * 3. All advertising materials mentioning features or use of this software 14326Salm * must display the following acknowledgement: 15326Salm * This product includes software developed by the University of 16326Salm * California, Berkeley and its contributors. 17326Salm * 4. Neither the name of the University nor the names of its contributors 18326Salm * may be used to endorse or promote products derived from this software 19326Salm * without specific prior written permission. 20326Salm * 21326Salm * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22326Salm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23326Salm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24326Salm * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25326Salm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26326Salm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27326Salm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28326Salm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29326Salm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30326Salm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31326Salm * SUCH DAMAGE. 32326Salm * 33621Srgrimes * from: @(#) floatingpoint.h 1.0 (Berkeley) 9/23/93 34719Swollman * $Id: floatingpoint.h,v 1.3 1993/10/16 14:39:18 rgrimes Exp $ 35326Salm */ 36326Salm 37326Salm/* 38326Salm * IEEE floating point structure and function definitions 39326Salm */ 40326Salm 41326Salm#ifndef _FLOATINGPOINT_H_ 42326Salm#define _FLOATINGPOINT_H_ 43326Salm 44326Salm#include <sys/cdefs.h> 45326Salm#include <sys/ieeefp.h> 46326Salm 47326Salm#ifdef __GNUC__ 48326Salm 49719Swollman#ifdef __i386__ 50719Swollman 51326Salm#define fnstcw(addr) __asm("fnstcw %0" : "=m" (*addr) : "0" (*addr)) 52326Salm#define fnstsw(addr) __asm("fnstsw %0" : "=m" (*addr) : "0" (*addr)) 53326Salm#define fnstenv(addr) __asm("fnstenv %0" : "=m" (*addr) : "0" (*addr)) 54326Salm#define fldenv(addr) __asm("fldenv %0" : : "m" (*addr)) 55326Salm 56326Salm 57326Salm/* 58326Salm * return the contents of a FP register 59326Salm */ 60338Salmstatic __inline__ int 61338Salm__fpgetreg(int _reg) 62326Salm{ 63338Salm unsigned short _mem; 64326Salm 65338Salm switch(_reg) { 66326Salm default: 67338Salm fnstcw(&_mem); 68326Salm break; 69326Salm case FP_STKY_REG: 70338Salm fnstsw(&_mem); 71326Salm break; 72326Salm } 73338Salm return _mem; 74326Salm} 75326Salm 76326Salm/* 77326Salm * set a FP mode; return previous mode 78326Salm */ 79338Salmstatic __inline__ int 80338Salm__fpsetreg(int _m, int _reg, int _fld, int _off) 81326Salm{ 82338Salm unsigned _env[7]; 83338Salm unsigned _p; 84326Salm 85338Salm fnstenv(_env); 86338Salm _p = (_env[_reg] & _fld) >> _off; 87338Salm _env[_reg] = (_env[_reg] & ~_fld) | (_m << _off & _fld); 88338Salm fldenv(_env); 89338Salm return _p; 90326Salm} 91326Salm 92326Salm#endif /* __i386__ */ 93326Salm 94326Salm#endif /* __GNUC__ */ 95326Salm 96326Salm/* 97326Salm * SysV/386 FP control interface 98326Salm */ 99326Salm#define fpgetround() ((__fpgetreg(FP_RND_REG) & FP_RND_FLD) >> FP_RND_OFF) 100326Salm#define fpsetround(m) __fpsetreg((m), FP_RND_REG, FP_RND_FLD, FP_RND_OFF) 101326Salm#define fpgetprec() ((__fpgetreg(FP_PRC_REG) & FP_PRC_FLD) >> FP_PRC_OFF) 102326Salm#define fpsetprec(m) __fpsetreg((m), FP_PRC_REG, FP_PRC_FLD, FP_PRC_OFF) 103326Salm#define fpgetmask() ((~__fpgetreg(FP_MSKS_REG) & FP_MSKS_FLD) >> FP_MSKS_OFF) 104326Salm#define fpsetmask(m) __fpsetreg(~(m), FP_MSKS_REG, FP_MSKS_FLD, FP_MSKS_OFF) 105326Salm#define fpgetsticky() ((__fpgetreg(FP_STKY_REG) & FP_STKY_FLD) >> FP_STKY_OFF) 106326Salm#define fpresetsticky(m) __fpsetreg(0, FP_STKY_REG, (m), FP_STKY_OFF) 107326Salm#define fpsetsticky(m) fpresetsticky(m) 108326Salm 109326Salm#endif /* !_FLOATINGPOINT_H_ */ 110