WebSVN – HelenOS-historic – Diff – /uspace/trunk/softfloat/generic/arithmetic.c


/*
 * Copyright (C) 2005 Josef Cejka
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */
 
#include<sftypes.h>
#include<arithmetic.h>
#include<comparison.h>
 
/** Add two Float32 numbers with same signs
 */
float32 addFloat32(float32 a, float32 b)
{
    int expdiff;
    __u32 exp1,exp2,mant1,mant2;
   
    expdiff=a.parts.exp - b.parts.exp;
    if (expdiff<0) {
        if (isFloat32NaN(b)) {
            //TODO: fix SigNaN
            if (isFloat32SigNaN(b)) {
            };
            return b;
        };
       
        if (b.parts.exp==0xFF) {
            return b;
        }
       
        mant1=b.parts.mantisa;
        exp1=b.parts.exp;
        mant2=a.parts.mantisa;
        exp2=a.parts.exp;
        expdiff*=-1;
    } else {
        if (isFloat32NaN(a)) {
            //TODO: fix SigNaN
            if ((isFloat32SigNaN(a))||(isFloat32SigNaN(b))) {
            };
            return a;
        };
       
        if (a.parts.exp==0xFF) {
            return a;
        }
       
        mant1=a.parts.mantisa;
        exp1=a.parts.exp;
        mant2=b.parts.mantisa;
        exp2=b.parts.exp;
    };
   
    if (exp1==0) {
        //both are denormalized
        mant1+=mant2;
        if (mant1&0xF00000) {
            a.parts.exp=1;
        };
        a.parts.mantisa=mant1;
        return a;
    };
   
    // create some space for rounding
    mant1<<=6;
    mant2<<=6;
   
    mant1|=0x20000000; //add hidden bit
   
   
    if (exp2==0) {
        --expdiff; 
    } else {
        mant2|=0x20000000; //hidden bit
    };
   
    if (expdiff>24) {
         goto done;
         };
   
    mant2>>=expdiff;
    mant1+=mant2;
done:
    if (mant1&0x40000000) {
        ++exp1;
        mant1>>=1;
    };
   
    //rounding - if first bit after mantisa is set then round up
    mant1+=0x20;
   
    a.parts.exp=exp1;
    a.parts.mantisa=mant1>>6;
    return a;
};
 
/** Substract two float32 numbers with same signs
 */
float32 subFloat32(float32 a, float32 b)
{
   
   
};
 
 

Rev 647	Rev 660
1	/*	1	/*
2	* Copyright (C) 2005 Josef Cejka	2	* Copyright (C) 2005 Josef Cejka
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	#include<sftypes.h>	29	#include<sftypes.h>
30	#include<arithmetic.h>	30	#include<arithmetic.h>
-		31	#include<comparison.h>
31		32
32	/** Add two Float32 numbers with same signs	33	/** Add two Float32 numbers with same signs
33	*/	34	*/
34	float32 addFloat32(float32 a, float32 b)	35	float32 addFloat32(float32 a, float32 b)
35	{	36	{
36	int expdiff;	37	int expdiff;
37	__u32 exp1,exp2,mant1,mant2;	38	__u32 exp1,exp2,mant1,mant2;
38		39
39	expdiff=a.parts.exp - b.parts.exp;	40	expdiff=a.parts.exp - b.parts.exp;
40	if (expdiff<0) {	41	if (expdiff<0) {
41	if (isFloat32NaN(b)) {	42	if (isFloat32NaN(b)) {
42	//TODO: fix SigNaN	43	//TODO: fix SigNaN
43	if (isFloat32SigNaN(b)) {	44	if (isFloat32SigNaN(b)) {
44	};	45	};
45	return b;	46	return b;
46	};	47	};
47		48
48	if (b.parts.exp==0xFF) {	49	if (b.parts.exp==0xFF) {
49	return b;	50	return b;
50	}	51	}
51		52
52	mant1=b.parts.mantisa;	53	mant1=b.parts.mantisa;
53	exp1=b.parts.exp;	54	exp1=b.parts.exp;
54	mant2=a.parts.mantisa;	55	mant2=a.parts.mantisa;
55	exp2=a.parts.exp;	56	exp2=a.parts.exp;
56	expdiff*=-1;	57	expdiff*=-1;
57	} else {	58	} else {
58	if (isFloat32NaN(a)) {	59	if (isFloat32NaN(a)) {
59	//TODO: fix SigNaN	60	//TODO: fix SigNaN
60	if ((isFloat32SigNaN(a))\|\|(isFloat32SigNaN(b))) {	61	if ((isFloat32SigNaN(a))\|\|(isFloat32SigNaN(b))) {
61	};	62	};
62	return a;	63	return a;
63	};	64	};
64		65
65	if (a.parts.exp==0xFF) {	66	if (a.parts.exp==0xFF) {
66	return a;	67	return a;
67	}	68	}
68		69
69	mant1=a.parts.mantisa;	70	mant1=a.parts.mantisa;
70	exp1=a.parts.exp;	71	exp1=a.parts.exp;
71	mant2=b.parts.mantisa;	72	mant2=b.parts.mantisa;
72	exp2=b.parts.exp;	73	exp2=b.parts.exp;
73	};	74	};
74		75
75	if (exp1==0) {	76	if (exp1==0) {
76	//both are denormalized	77	//both are denormalized
77	mant1+=mant2;	78	mant1+=mant2;
78	if (mant1&0xF00000) {	79	if (mant1&0xF00000) {
79	a.parts.exp=1;	80	a.parts.exp=1;
80	};	81	};
81	a.parts.mantisa=mant1;	82	a.parts.mantisa=mant1;
82	return a;	83	return a;
83	};	84	};
84		85
85	// create some space for rounding	86	// create some space for rounding
86	mant1<<=6;	87	mant1<<=6;
87	mant2<<=6;	88	mant2<<=6;
88		89
89	mant1\|=0x20000000; //add hidden bit	90	mant1\|=0x20000000; //add hidden bit
90		91
91		92
92	if (exp2==0) {	93	if (exp2==0) {
93	--expdiff;	94	--expdiff;
94	} else {	95	} else {
95	mant2\|=0x20000000; //hidden bit	96	mant2\|=0x20000000; //hidden bit
96	};	97	};
97		98
98	if (expdiff>24) {	99	if (expdiff>24) {
99	goto done;	100	goto done;
100	};	101	};
101		102
102	mant2>>=expdiff;	103	mant2>>=expdiff;
103	mant1+=mant2;	104	mant1+=mant2;
104	done:	105	done:
105	if (mant1&0x40000000) {	106	if (mant1&0x40000000) {
106	++exp1;	107	++exp1;
107	mant1>>=1;	108	mant1>>=1;
108	};	109	};
109		110
110	//rounding - if first bit after mantisa is set then round up	111	//rounding - if first bit after mantisa is set then round up
111	mant1+=0x20;	112	mant1+=0x20;
112		113
113	a.parts.exp=exp1;	114	a.parts.exp=exp1;
114	a.parts.mantisa=mant1>>6;	115	a.parts.mantisa=mant1>>6;
115	return a;	116	return a;
116	};	117	};
117		118
118	/** Substract two float32 numbers with same signs	119	/** Substract two float32 numbers with same signs
119	*/	120	*/
120	float32 subFloat32(float32 a, float32 b)	121	float32 subFloat32(float32 a, float32 b)
121	{	122	{
122		123
123		124
124	};	125	};
125		126
126		127

Subversion Repositories HelenOS-historic

(root)/uspace/trunk/softfloat/generic/arithmetic.c – Rev 647 → 660