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[/] [or1k_soc_on_altera_embedded_dev_kit/] [trunk/] [linux-2.6/] [linux-2.6.24/] [arch/] [mips/] [math-emu/] [sp_div.c] - Blame information for rev 19

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/* IEEE754 floating point arithmetic
 * single precision
 */
/*
 * 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 "ieee754sp.h"
 
ieee754sp ieee754sp_div(ieee754sp x, ieee754sp y)
{
        COMPXSP;
        COMPYSP;
 
        EXPLODEXSP;
        EXPLODEYSP;
 
        CLEARCX;
 
        FLUSHXSP;
        FLUSHYSP;
 
        switch (CLPAIR(xc, yc)) {
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
        case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
                SETCX(IEEE754_INVALID_OPERATION);
                return ieee754sp_nanxcpt(ieee754sp_indef(), "div", x, y);
 
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
                return y;
 
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
        case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
                return x;
 
 
                /* Infinity handling
                 */
 
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
                SETCX(IEEE754_INVALID_OPERATION);
                return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);
 
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
                return ieee754sp_zero(xs ^ ys);
 
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
        case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
                return ieee754sp_inf(xs ^ ys);
 
                /* Zero handling
                 */
 
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
                SETCX(IEEE754_INVALID_OPERATION);
                return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);
 
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
                SETCX(IEEE754_ZERO_DIVIDE);
                return ieee754sp_xcpt(ieee754sp_inf(xs ^ ys), "div", x, y);
 
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
        case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
                return ieee754sp_zero(xs == ys ? 0 : 1);
 
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
                SPDNORMX;
 
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
                SPDNORMY;
                break;
 
        case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
                SPDNORMX;
                break;
 
        case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
                break;
        }
        assert(xm & SP_HIDDEN_BIT);
        assert(ym & SP_HIDDEN_BIT);
 
        /* provide rounding space */
        xm <<= 3;
        ym <<= 3;
 
        {
                /* now the dirty work */
 
                unsigned rm = 0;
                int re = xe - ye;
                unsigned bm;
 
                for (bm = SP_MBIT(SP_MBITS + 2); bm; bm >>= 1) {
                        if (xm >= ym) {
                                xm -= ym;
                                rm |= bm;
                                if (xm == 0)
                                        break;
                        }
                        xm <<= 1;
                }
                rm <<= 1;
                if (xm)
                        rm |= 1;        /* have remainder, set sticky */
 
                assert(rm);
 
                /* normalise rm to rounding precision ?
                 */
                while ((rm >> (SP_MBITS + 3)) == 0) {
                        rm <<= 1;
                        re--;
                }
 
                SPNORMRET2(xs == ys ? 0 : 1, re, rm, "div", x, y);
        }
}

Line No.	Rev	Author	Line
1	3	xianfeng	`/* IEEE754 floating point arithmetic`
2			`* single precision`
3			`*/`
4			`/*`
5			`* MIPS floating point support`
6			`* Copyright (C) 1994-2000 Algorithmics Ltd.`
7			`* http://www.algor.co.uk`
8			`*`
9			`* ########################################################################`
10			`*`
11			`* This program is free software; you can distribute it and/or modify it`
12			`* under the terms of the GNU General Public License (Version 2) as`
13			`* published by the Free Software Foundation.`
14			`*`
15			`* This program is distributed in the hope it will be useful, but WITHOUT`
16			`* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or`
17			`* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License`
18			`* for more details.`
19			`*`
20			`* You should have received a copy of the GNU General Public License along`
21			`* with this program; if not, write to the Free Software Foundation, Inc.,`
22			`* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.`
23			`*`
24			`* ########################################################################`
25			`*/`
26
27
28			`#include "ieee754sp.h"`
29
30			`ieee754sp ieee754sp_div(ieee754sp x, ieee754sp y)`
31			`{`
32			`COMPXSP;`
33			`COMPYSP;`
34
35			`EXPLODEXSP;`
36			`EXPLODEYSP;`
37
38			`CLEARCX;`
39
40			`FLUSHXSP;`
41			`FLUSHYSP;`
42
43			`switch (CLPAIR(xc, yc)) {`
44			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):`
45			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):`
46			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):`
47			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):`
48			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):`
49			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):`
50			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):`
51			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):`
52			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):`
53			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):`
54			`case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):`
55			`SETCX(IEEE754_INVALID_OPERATION);`
56			`return ieee754sp_nanxcpt(ieee754sp_indef(), "div", x, y);`
57
58			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):`
59			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):`
60			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):`
61			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):`
62			`return y;`
63
64			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):`
65			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):`
66			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):`
67			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):`
68			`case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):`
69			`return x;`
70
71
72			`/* Infinity handling`
73			`*/`
74
75			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):`
76			`SETCX(IEEE754_INVALID_OPERATION);`
77			`return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);`
78
79			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):`
80			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):`
81			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):`
82			`return ieee754sp_zero(xs ^ ys);`
83
84			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):`
85			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):`
86			`case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):`
87			`return ieee754sp_inf(xs ^ ys);`
88
89			`/* Zero handling`
90			`*/`
91
92			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):`
93			`SETCX(IEEE754_INVALID_OPERATION);`
94			`return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);`
95
96			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):`
97			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):`
98			`SETCX(IEEE754_ZERO_DIVIDE);`
99			`return ieee754sp_xcpt(ieee754sp_inf(xs ^ ys), "div", x, y);`
100
101			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):`
102			`case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):`
103			`return ieee754sp_zero(xs == ys ? 0 : 1);`
104
105			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):`
106			`SPDNORMX;`
107
108			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):`
109			`SPDNORMY;`
110			`break;`
111
112			`case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):`
113			`SPDNORMX;`
114			`break;`
115
116			`case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):`
117			`break;`
118			`}`
119			`assert(xm & SP_HIDDEN_BIT);`
120			`assert(ym & SP_HIDDEN_BIT);`
121
122			`/* provide rounding space */`
123			`xm <<= 3;`
124			`ym <<= 3;`
125
126			`{`
127			`/* now the dirty work */`
128
129			`unsigned rm = 0;`
130			`int re = xe - ye;`
131			`unsigned bm;`
132
133			`for (bm = SP_MBIT(SP_MBITS + 2); bm; bm >>= 1) {`
134			`if (xm >= ym) {`
135			`xm -= ym;`
136			`rm \|= bm;`
137			`if (xm == 0)`
138			`break;`
139			`}`
140			`xm <<= 1;`
141			`}`
142			`rm <<= 1;`
143			`if (xm)`
144			`rm \|= 1; /* have remainder, set sticky */`
145
146			`assert(rm);`
147
148			`/* normalise rm to rounding precision ?`
149			`*/`
150			`while ((rm >> (SP_MBITS + 3)) == 0) {`
151			`rm <<= 1;`
152			`re--;`
153			`}`
154
155			`SPNORMRET2(xs == ys ? 0 : 1, re, rm, "div", x, y);`
156			`}`
157			`}`

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Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

[/] [or1k_soc_on_altera_embedded_dev_kit/] [trunk/] [linux-2.6/] [linux-2.6.24/] [arch/] [mips/] [math-emu/] [sp_div.c] - Blame information for rev 19