WSL2-Linux-Kernel/arch/mips/math-emu/ieee754.c

127 строки
3.8 KiB
C

/* ieee754 floating point arithmetic
* single and double precision
*
* BUGS
* not much dp done
* doesn't generate IEEE754_INEXACT
*
*/
/*
* MIPS floating point support
* Copyright (C) 1994-2000 Algorithmics Ltd.
* http://www.algor.co.uk
*
* ########################################################################
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* ########################################################################
*/
#include "ieee754int.h"
#include "ieee754sp.h"
#include "ieee754dp.h"
#define DP_EBIAS 1023
#define DP_EMIN (-1022)
#define DP_EMAX 1023
#define SP_EBIAS 127
#define SP_EMIN (-126)
#define SP_EMAX 127
/* special constants
*/
#if (defined(BYTE_ORDER) && BYTE_ORDER == LITTLE_ENDIAN) || defined(__MIPSEL__)
#define SPSTR(s,b,m) {m,b,s}
#define DPSTR(s,b,mh,ml) {ml,mh,b,s}
#endif
#ifdef __MIPSEB__
#define SPSTR(s,b,m) {s,b,m}
#define DPSTR(s,b,mh,ml) {s,b,mh,ml}
#endif
const struct ieee754dp_konst __ieee754dp_spcvals[] = {
DPSTR(0, DP_EMIN - 1 + DP_EBIAS, 0, 0), /* + zero */
DPSTR(1, DP_EMIN - 1 + DP_EBIAS, 0, 0), /* - zero */
DPSTR(0, DP_EBIAS, 0, 0), /* + 1.0 */
DPSTR(1, DP_EBIAS, 0, 0), /* - 1.0 */
DPSTR(0, 3 + DP_EBIAS, 0x40000, 0), /* + 10.0 */
DPSTR(1, 3 + DP_EBIAS, 0x40000, 0), /* - 10.0 */
DPSTR(0, DP_EMAX + 1 + DP_EBIAS, 0, 0), /* + infinity */
DPSTR(1, DP_EMAX + 1 + DP_EBIAS, 0, 0), /* - infinity */
DPSTR(0,DP_EMAX+1+DP_EBIAS,0x7FFFF,0xFFFFFFFF), /* + indef quiet Nan */
DPSTR(0, DP_EMAX + DP_EBIAS, 0xFFFFF, 0xFFFFFFFF), /* + max */
DPSTR(1, DP_EMAX + DP_EBIAS, 0xFFFFF, 0xFFFFFFFF), /* - max */
DPSTR(0, DP_EMIN + DP_EBIAS, 0, 0), /* + min normal */
DPSTR(1, DP_EMIN + DP_EBIAS, 0, 0), /* - min normal */
DPSTR(0, DP_EMIN - 1 + DP_EBIAS, 0, 1), /* + min denormal */
DPSTR(1, DP_EMIN - 1 + DP_EBIAS, 0, 1), /* - min denormal */
DPSTR(0, 31 + DP_EBIAS, 0, 0), /* + 1.0e31 */
DPSTR(0, 63 + DP_EBIAS, 0, 0), /* + 1.0e63 */
};
const struct ieee754sp_konst __ieee754sp_spcvals[] = {
SPSTR(0, SP_EMIN - 1 + SP_EBIAS, 0), /* + zero */
SPSTR(1, SP_EMIN - 1 + SP_EBIAS, 0), /* - zero */
SPSTR(0, SP_EBIAS, 0), /* + 1.0 */
SPSTR(1, SP_EBIAS, 0), /* - 1.0 */
SPSTR(0, 3 + SP_EBIAS, 0x200000), /* + 10.0 */
SPSTR(1, 3 + SP_EBIAS, 0x200000), /* - 10.0 */
SPSTR(0, SP_EMAX + 1 + SP_EBIAS, 0), /* + infinity */
SPSTR(1, SP_EMAX + 1 + SP_EBIAS, 0), /* - infinity */
SPSTR(0,SP_EMAX+1+SP_EBIAS,0x3FFFFF), /* + indef quiet Nan */
SPSTR(0, SP_EMAX + SP_EBIAS, 0x7FFFFF), /* + max normal */
SPSTR(1, SP_EMAX + SP_EBIAS, 0x7FFFFF), /* - max normal */
SPSTR(0, SP_EMIN + SP_EBIAS, 0), /* + min normal */
SPSTR(1, SP_EMIN + SP_EBIAS, 0), /* - min normal */
SPSTR(0, SP_EMIN - 1 + SP_EBIAS, 1), /* + min denormal */
SPSTR(1, SP_EMIN - 1 + SP_EBIAS, 1), /* - min denormal */
SPSTR(0, 31 + SP_EBIAS, 0), /* + 1.0e31 */
SPSTR(0, 63 + SP_EBIAS, 0), /* + 1.0e63 */
};
int ieee754si_xcpt(int r, const char *op, ...)
{
struct ieee754xctx ax;
if (!TSTX())
return r;
ax.op = op;
ax.rt = IEEE754_RT_SI;
ax.rv.si = r;
va_start(ax.ap, op);
ieee754_xcpt(&ax);
return ax.rv.si;
}
s64 ieee754di_xcpt(s64 r, const char *op, ...)
{
struct ieee754xctx ax;
if (!TSTX())
return r;
ax.op = op;
ax.rt = IEEE754_RT_DI;
ax.rv.di = r;
va_start(ax.ap, op);
ieee754_xcpt(&ax);
return ax.rv.di;
}