WebSVN – HelenOS – Diff – /uspace/trunk/softfloat/generic/add.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<add.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 == FLOAT32_MAX_EXPONENT) {
            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 == FLOAT32_MAX_EXPONENT) {
            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 & FLOAT32_HIDDEN_BIT_MASK ) {
            /* result is not denormalized */
            a.parts.exp = 1;
        };
        a.parts.mantisa = mant1;
        return a;
    };
   
    mant1 |= FLOAT32_HIDDEN_BIT_MASK; //add hidden bit
 
    if (exp2 == 0) {
        /* second operand is denormalized */
        --expdiff; 
    } else {
        /* add hidden bit to second operand */
        mant2 |= FLOAT32_HIDDEN_BIT_MASK;
    };
   
    /* create some space for rounding */
    mant1 <<= 6;
    mant2 <<= 6;
   
    if (expdiff > (FLOAT32_MANTISA_SIZE + 1) ) {
         goto done;
         };
   
    mant2 >>= expdiff;
    mant1 += mant2;
done:
    if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {
        ++exp1;
        mant1 >>= 1;
    };
   
    /* rounding - if first bit after mantisa is set then round up */
    mant1 += (0x1 << 5);
   
    if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {
        ++exp1;
        mant1 >>= 1;
    };
   
    a.parts.exp = exp1;
   
    /*Clear hidden bit and shift */
    a.parts.mantisa = ((mant1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;
    return a;
}
 
 
/** Add two Float64 numbers with same signs
 */
float64 addFloat64(float64 a, float64 b)
{
    int expdiff;
    __u64 exp1, exp2, mant1, mant2;
   
    expdiff = a.parts.exp - b.parts.exp;
    if (expdiff < 0) {
        if (isFloat64NaN(b)) {
            //TODO: fix SigNaN
            if (isFloat64SigNaN(b)) {
            };
 
            return b;
        };
       
        /* b is infinity and a not */  
        if (b.parts.exp == FLOAT64_MAX_EXPONENT ) {
            return b;
        }
       
        mant1 = b.parts.mantisa;
        exp1 = b.parts.exp;
        mant2 = a.parts.mantisa;
        exp2 = a.parts.exp;
        expdiff *= -1;
    } else {
        if (isFloat64NaN(a)) {
            //TODO: fix SigNaN
            if (isFloat64SigNaN(a) || isFloat64SigNaN(b)) {
            };
            return a;
        };
       
        /* a is infinity and b not */
        if (a.parts.exp == FLOAT64_MAX_EXPONENT ) {
            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 & FLOAT64_HIDDEN_BIT_MASK) {
            /* result is not denormalized */
            a.parts.exp = 1;
        };
        a.parts.mantisa = mant1;
        return a;
    };
   
    /* add hidden bit - mant1 is sure not denormalized */
    mant1 |= FLOAT64_HIDDEN_BIT_MASK;
 
    /* second operand ... */
    if (exp2 == 0) {
        /* ... is denormalized */
        --expdiff; 
    } else {
        /* is not denormalized */
        mant2 |= FLOAT64_HIDDEN_BIT_MASK;
    };
   
    /* create some space for rounding */
    mant1 <<= 6;
    mant2 <<= 6;
   
    if (expdiff > (FLOAT64_MANTISA_SIZE + 1) ) {
         goto done;
         };
   
    mant2 >>= expdiff;
    mant1 += mant2;
done:
    if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {
        ++exp1;
        mant1 >>= 1;
    };
   
    /* rounding - if first bit after mantisa is set then round up */
    mant1 += (0x1 << 5);
   
    if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {
        ++exp1;
        mant1 >>= 1;
    };
   
    a.parts.exp = exp1;
    /*Clear hidden bit and shift */
    a.parts.mantisa = ( (mant1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));
    return a;
}
 
 
 

Rev 731	Rev 732
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<add.h>	30	#include<add.h>
31	#include<comparison.h>	31	#include<comparison.h>
32		32
33	/** Add two Float32 numbers with same signs	33	/** Add two Float32 numbers with same signs
34	*/	34	*/
35	float32 addFloat32(float32 a, float32 b)	35	float32 addFloat32(float32 a, float32 b)
36	{	36	{
37	int expdiff;	37	int expdiff;
38	__u32 exp1, exp2,mant1, mant2;	38	__u32 exp1, exp2,mant1, mant2;
39		39
40	expdiff=a.parts.exp - b.parts.exp;	40	expdiff = a.parts.exp - b.parts.exp;
41	if (expdiff<0) {	41	if (expdiff < 0) {
42	if (isFloat32NaN(b)) {	42	if (isFloat32NaN(b)) {
43	//TODO: fix SigNaN	43	//TODO: fix SigNaN
44	if (isFloat32SigNaN(b)) {	44	if (isFloat32SigNaN(b)) {
45	};	45	};
46		46
47	return b;	47	return b;
48	};	48	};
49		49
50	if (b.parts.exp==0xFF) {	50	if (b.parts.exp == FLOAT32_MAX_EXPONENT) {
51	return b;	51	return b;
52	}	52	}
53		53
54	mant1=b.parts.mantisa;	54	mant1 = b.parts.mantisa;
55	exp1=b.parts.exp;	55	exp1 = b.parts.exp;
56	mant2=a.parts.mantisa;	56	mant2 = a.parts.mantisa;
57	exp2=a.parts.exp;	57	exp2 = a.parts.exp;
58	expdiff*=-1;	58	expdiff *= -1;
59	} else {	59	} else {
60	if (isFloat32NaN(a)) {	60	if (isFloat32NaN(a)) {
61	//TODO: fix SigNaN	61	//TODO: fix SigNaN
62	if ((isFloat32SigNaN(a))\|\|(isFloat32SigNaN(b))) {	62	if (isFloat32SigNaN(a) \|\| isFloat32SigNaN(b)) {
63	};	63	};
64	return a;	64	return a;
65	};	65	};
66		66
67	if (a.parts.exp==0xFF) {	67	if (a.parts.exp == FLOAT32_MAX_EXPONENT) {
68	return a;	68	return a;
69	}	69	}
70		70
71	mant1=a.parts.mantisa;	71	mant1 = a.parts.mantisa;
72	exp1=a.parts.exp;	72	exp1 = a.parts.exp;
73	mant2=b.parts.mantisa;	73	mant2 = b.parts.mantisa;
74	exp2=b.parts.exp;	74	exp2 = b.parts.exp;
75	};	75	};
76		76
77	if (exp1 == 0) {	77	if (exp1 == 0) {
78	/* both are denormalized */	78	/* both are denormalized */
79	mant1 += mant2;	79	mant1 += mant2;
80	if (mant1 & FLOAT32_HIDDEN_BIT_MASK ) {	80	if (mant1 & FLOAT32_HIDDEN_BIT_MASK ) {
81	/* result is not denormalized */	81	/* result is not denormalized */
82	a.parts.exp = 1;	82	a.parts.exp = 1;
83	};	83	};
84	a.parts.mantisa = mant1;	84	a.parts.mantisa = mant1;
85	return a;	85	return a;
86	};	86	};
87		87
88	mant1 \|= FLOAT32_HIDDEN_BIT_MASK; //add hidden bit	88	mant1 \|= FLOAT32_HIDDEN_BIT_MASK; //add hidden bit
89		89
90	if (exp2 == 0) {	90	if (exp2 == 0) {
91	/* second operand is denormalized */	91	/* second operand is denormalized */
92	--expdiff;	92	--expdiff;
93	} else {	93	} else {
94	/* add hidden bit to second operand */	94	/* add hidden bit to second operand */
95	mant2 \|= FLOAT32_HIDDEN_BIT_MASK;	95	mant2 \|= FLOAT32_HIDDEN_BIT_MASK;
96	};	96	};
97		97
98	/* create some space for rounding */	98	/* create some space for rounding */
99	mant1 <<= 6;	99	mant1 <<= 6;
100	mant2 <<= 6;	100	mant2 <<= 6;
101		101
102	if (expdiff > 24) {	102	if (expdiff > (FLOAT32_MANTISA_SIZE + 1) ) {
103	goto done;	103	goto done;
104	};	104	};
105		105
106	mant2>>=expdiff;	106	mant2 >>= expdiff;
107	mant1+=mant2;	107	mant1 += mant2;
108	done:	108	done:
109	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 6) ) {	109	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {
110	++exp1;	110	++exp1;
111	mant1 >>= 1;	111	mant1 >>= 1;
112	};	112	};
113		113
114	/* rounding - if first bit after mantisa is set then round up */	114	/* rounding - if first bit after mantisa is set then round up */
115	mant1 += (0x1 << 5);	115	mant1 += (0x1 << 5);
116		116
117	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 6)) {	117	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {
118	++exp1;	118	++exp1;
119	mant1 >> =1;	119	mant1 >>= 1;
120	};	120	};
121		121
122	a.parts.exp = exp1;	122	a.parts.exp = exp1;
123		123
124	/Clear hidden bit and shift /	124	/Clear hidden bit and shift /
125	a.parts.mantisa = ((mant1>>6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;	125	a.parts.mantisa = ((mant1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;
126	return a;	126	return a;
127	}	127	}
128		128
129		129
130	/** Add two Float64 numbers with same signs	130	/** Add two Float64 numbers with same signs
131	*/	131	*/
132	float64 addFloat64(float64 a, float64 b)	132	float64 addFloat64(float64 a, float64 b)
133	{	133	{
134	int expdiff;	134	int expdiff;
135	__u64 exp1,exp2,mant1,mant2;	135	__u64 exp1, exp2, mant1, mant2;
136		136
137	expdiff=a.parts.exp - b.parts.exp;	137	expdiff = a.parts.exp - b.parts.exp;
138	if (expdiff<0) {	138	if (expdiff < 0) {
139	if (isFloat64NaN(b)) {	139	if (isFloat64NaN(b)) {
140	//TODO: fix SigNaN	140	//TODO: fix SigNaN
141	if (isFloat64SigNaN(b)) {	141	if (isFloat64SigNaN(b)) {
142	};	142	};
143		143
144	return b;	144	return b;
145	};	145	};
146		146
147	/* b is infinity and a not */	147	/* b is infinity and a not */
148	if (b.parts.exp==0x8FF) {	148	if (b.parts.exp == FLOAT64_MAX_EXPONENT ) {
149	return b;	149	return b;
150	}	150	}
151		151
152	mant1=b.parts.mantisa;	152	mant1 = b.parts.mantisa;
153	exp1=b.parts.exp;	153	exp1 = b.parts.exp;
154	mant2=a.parts.mantisa;	154	mant2 = a.parts.mantisa;
155	exp2=a.parts.exp;	155	exp2 = a.parts.exp;
156	expdiff*=-1;	156	expdiff *= -1;
157	} else {	157	} else {
158	if (isFloat64NaN(a)) {	158	if (isFloat64NaN(a)) {
159	//TODO: fix SigNaN	159	//TODO: fix SigNaN
160	if ((isFloat64SigNaN(a))\|\|(isFloat64SigNaN(b))) {	160	if (isFloat64SigNaN(a) \|\| isFloat64SigNaN(b)) {
161	};	161	};
162	return a;	162	return a;
163	};	163	};
164		164
165	/* a is infinity and b not */	165	/* a is infinity and b not */
166	if (a.parts.exp == 0x8FF) {	166	if (a.parts.exp == FLOAT64_MAX_EXPONENT ) {
167	return a;	167	return a;
168	}	168	}
169		169
170	mant1 = a.parts.mantisa;	170	mant1 = a.parts.mantisa;
171	exp1 = a.parts.exp;	171	exp1 = a.parts.exp;
172	mant2 = b.parts.mantisa;	172	mant2 = b.parts.mantisa;
173	exp2 = b.parts.exp;	173	exp2 = b.parts.exp;
174	};	174	};
175		175
176	if (exp1 == 0) {	176	if (exp1 == 0) {
177	/* both are denormalized */	177	/* both are denormalized */
178	mant1 += mant2;	178	mant1 += mant2;
179	if (mant1 & FLOAT64_HIDDEN_BIT_MASK) {	179	if (mant1 & FLOAT64_HIDDEN_BIT_MASK) {
180	/* result is not denormalized */	180	/* result is not denormalized */
181	a.parts.exp = 1;	181	a.parts.exp = 1;
182	};	182	};
183	a.parts.mantisa = mant1;	183	a.parts.mantisa = mant1;
184	return a;	184	return a;
185	};	185	};
186		186
187	/* add hidden bit - mant1 is sure not denormalized */	187	/* add hidden bit - mant1 is sure not denormalized */
188	mant1 \|= FLOAT64_HIDDEN_BIT_MASK;	188	mant1 \|= FLOAT64_HIDDEN_BIT_MASK;
189		189
190	/* second operand ... */	190	/* second operand ... */
191	if (exp2 == 0) {	191	if (exp2 == 0) {
192	/* ... is denormalized */	192	/* ... is denormalized */
193	--expdiff;	193	--expdiff;
194	} else {	194	} else {
195	/* is not denormalized */	195	/* is not denormalized */
196	mant2 \|= FLOAT64_HIDDEN_BIT_MASK;	196	mant2 \|= FLOAT64_HIDDEN_BIT_MASK;
197	};	197	};
198		198
199	/* create some space for rounding */	199	/* create some space for rounding */
200	mant1 <<= 6;	200	mant1 <<= 6;
201	mant2 <<= 6;	201	mant2 <<= 6;
202		202
203	if (expdiff > 53) {	203	if (expdiff > (FLOAT64_MANTISA_SIZE + 1) ) {
204	goto done;	204	goto done;
205	};	205	};
206		206
207	mant2 >>= expdiff;	207	mant2 >>= expdiff;
208	mant1 += mant2;	208	mant1 += mant2;
209	done:	209	done:
210	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 6) ) {	210	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {
211	++exp1;	211	++exp1;
212	mant1 >>= 1;	212	mant1 >>= 1;
213	};	213	};
214		214
215	/* rounding - if first bit after mantisa is set then round up */	215	/* rounding - if first bit after mantisa is set then round up */
216	mant1 += (0x1 << 5);	216	mant1 += (0x1 << 5);
217		217
218	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 6)) {	218	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {
219	++exp1;	219	++exp1;
220	mant1 >> =1;	220	mant1 >>= 1;
221	};	221	};
222		222
223	a.parts.exp = exp1;	223	a.parts.exp = exp1;
224	/Clear hidden bit and shift /	224	/Clear hidden bit and shift /
225	a.parts.mantisa = ( (mant1 >>6 ) & (~ (FLOAT64_HIDDEN_BIT_MASK)));	225	a.parts.mantisa = ( (mant1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));
226	return a;	226	return a;
227	}	227	}
228		228
229		229
230		230

Subversion Repositories HelenOS

(root)/uspace/trunk/softfloat/generic/add.c – Rev 731 → 732