WebSVN – HelenOS-historic – 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.
 */
 
 /** @addtogroup softfloat 
 * @{
 */
/** @file
 */
 
#include<sftypes.h>
#include<add.h>
#include<comparison.h>
 
/** Add two Float32 numbers with same signs
 */
float32 addFloat32(float32 a, float32 b)
{
    int expdiff;
    uint32_t exp1, exp2,frac1, frac2;
   
    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;
        }
       
        frac1 = b.parts.fraction;
        exp1 = b.parts.exp;
        frac2 = a.parts.fraction;
        exp2 = a.parts.exp;
        expdiff *= -1;
    } else {
        if ((isFloat32NaN(a)) || (isFloat32NaN(b))) {
            /* TODO: fix SigNaN */
            if (isFloat32SigNaN(a) || isFloat32SigNaN(b)) {
            };
            return (isFloat32NaN(a)?a:b);
        };
       
        if (a.parts.exp == FLOAT32_MAX_EXPONENT) {
            return a;
        }
       
        frac1 = a.parts.fraction;
        exp1 = a.parts.exp;
        frac2 = b.parts.fraction;
        exp2 = b.parts.exp;
    };
   
    if (exp1 == 0) {
        /* both are denormalized */
        frac1 += frac2;
        if (frac1 & FLOAT32_HIDDEN_BIT_MASK ) {
            /* result is not denormalized */
            a.parts.exp = 1;
        };
        a.parts.fraction = frac1;
        return a;
    };
   
    frac1 |= FLOAT32_HIDDEN_BIT_MASK; /* add hidden bit */
 
    if (exp2 == 0) {
        /* second operand is denormalized */
        --expdiff;
    } else {
        /* add hidden bit to second operand */
        frac2 |= FLOAT32_HIDDEN_BIT_MASK;
    };
   
    /* create some space for rounding */
    frac1 <<= 6;
    frac2 <<= 6;
   
    if (expdiff < (FLOAT32_FRACTION_SIZE + 2) ) {
        frac2 >>= expdiff;
        frac1 += frac2;
    } else {
        a.parts.exp = exp1;
        a.parts.fraction = (frac1 >> 6) & (~(FLOAT32_HIDDEN_BIT_MASK));
        return a;
    }
   
    if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {
        ++exp1;
        frac1 >>= 1;
    };
   
    /* rounding - if first bit after fraction is set then round up */
    frac1 += (0x1 << 5);
   
    if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {
        /* rounding overflow */
        ++exp1;
        frac1 >>= 1;
    };
   
   
    if ((exp1 == FLOAT32_MAX_EXPONENT ) || (exp2 > exp1)) {
            /* overflow - set infinity as result */
            a.parts.exp = FLOAT32_MAX_EXPONENT;
            a.parts.fraction = 0;
            return a;
            }
   
    a.parts.exp = exp1;
   
    /*Clear hidden bit and shift */
    a.parts.fraction = ((frac1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;
    return a;
}
 
 
/** Add two Float64 numbers with same signs
 */
float64 addFloat64(float64 a, float64 b)
{
    int expdiff;
    uint32_t exp1, exp2;
    uint64_t frac1, frac2;
   
    expdiff = ((int )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;
        }
       
        frac1 = b.parts.fraction;
        exp1 = b.parts.exp;
        frac2 = a.parts.fraction;
        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;
        }
       
        frac1 = a.parts.fraction;
        exp1 = a.parts.exp;
        frac2 = b.parts.fraction;
        exp2 = b.parts.exp;
    };
   
    if (exp1 == 0) {
        /* both are denormalized */
        frac1 += frac2;
        if (frac1 & FLOAT64_HIDDEN_BIT_MASK) {
            /* result is not denormalized */
            a.parts.exp = 1;
        };
        a.parts.fraction = frac1;
        return a;
    };
   
    /* add hidden bit - frac1 is sure not denormalized */
    frac1 |= FLOAT64_HIDDEN_BIT_MASK;
 
    /* second operand ... */
    if (exp2 == 0) {
        /* ... is denormalized */
        --expdiff; 
    } else {
        /* is not denormalized */
        frac2 |= FLOAT64_HIDDEN_BIT_MASK;
    };
   
    /* create some space for rounding */
    frac1 <<= 6;
    frac2 <<= 6;
   
    if (expdiff < (FLOAT64_FRACTION_SIZE + 2) ) {
        frac2 >>= expdiff;
        frac1 += frac2;
    } else {
        a.parts.exp = exp1;
        a.parts.fraction = (frac1 >> 6) & (~(FLOAT64_HIDDEN_BIT_MASK));
        return a;
    }
   
    if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {
        ++exp1;
        frac1 >>= 1;
    };
   
    /* rounding - if first bit after fraction is set then round up */
    frac1 += (0x1 << 5);
   
    if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {
        /* rounding overflow */
        ++exp1;
        frac1 >>= 1;
    };
   
    if ((exp1 == FLOAT64_MAX_EXPONENT ) || (exp2 > exp1)) {
            /* overflow - set infinity as result */
            a.parts.exp = FLOAT64_MAX_EXPONENT;
            a.parts.fraction = 0;
            return a;
            }
   
    a.parts.exp = exp1;
    /*Clear hidden bit and shift */
    a.parts.fraction = ( (frac1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));
   
    return a;
}
 
 
 
 /** @}
 */
 
 

Rev 1031	Rev 1657
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	/** @addtogroup softfloat
-		30	* @{
-		31	*/
-		32	/** @file
-		33	*/
-		34
29	#include<sftypes.h>	35	#include<sftypes.h>
30	#include<add.h>	36	#include<add.h>
31	#include<comparison.h>	37	#include<comparison.h>
32		38
33	/** Add two Float32 numbers with same signs	39	/** Add two Float32 numbers with same signs
34	*/	40	*/
35	float32 addFloat32(float32 a, float32 b)	41	float32 addFloat32(float32 a, float32 b)
36	{	42	{
37	int expdiff;	43	int expdiff;
38	uint32_t exp1, exp2,frac1, frac2;	44	uint32_t exp1, exp2,frac1, frac2;
39		45
40	expdiff = a.parts.exp - b.parts.exp;	46	expdiff = a.parts.exp - b.parts.exp;
41	if (expdiff < 0) {	47	if (expdiff < 0) {
42	if (isFloat32NaN(b)) {	48	if (isFloat32NaN(b)) {
43	/* TODO: fix SigNaN */	49	/* TODO: fix SigNaN */
44	if (isFloat32SigNaN(b)) {	50	if (isFloat32SigNaN(b)) {
45	};	51	};
46		52
47	return b;	53	return b;
48	};	54	};
49		55
50	if (b.parts.exp == FLOAT32_MAX_EXPONENT) {	56	if (b.parts.exp == FLOAT32_MAX_EXPONENT) {
51	return b;	57	return b;
52	}	58	}
53		59
54	frac1 = b.parts.fraction;	60	frac1 = b.parts.fraction;
55	exp1 = b.parts.exp;	61	exp1 = b.parts.exp;
56	frac2 = a.parts.fraction;	62	frac2 = a.parts.fraction;
57	exp2 = a.parts.exp;	63	exp2 = a.parts.exp;
58	expdiff *= -1;	64	expdiff *= -1;
59	} else {	65	} else {
60	if ((isFloat32NaN(a)) \|\| (isFloat32NaN(b))) {	66	if ((isFloat32NaN(a)) \|\| (isFloat32NaN(b))) {
61	/* TODO: fix SigNaN */	67	/* TODO: fix SigNaN */
62	if (isFloat32SigNaN(a) \|\| isFloat32SigNaN(b)) {	68	if (isFloat32SigNaN(a) \|\| isFloat32SigNaN(b)) {
63	};	69	};
64	return (isFloat32NaN(a)?a:b);	70	return (isFloat32NaN(a)?a:b);
65	};	71	};
66		72
67	if (a.parts.exp == FLOAT32_MAX_EXPONENT) {	73	if (a.parts.exp == FLOAT32_MAX_EXPONENT) {
68	return a;	74	return a;
69	}	75	}
70		76
71	frac1 = a.parts.fraction;	77	frac1 = a.parts.fraction;
72	exp1 = a.parts.exp;	78	exp1 = a.parts.exp;
73	frac2 = b.parts.fraction;	79	frac2 = b.parts.fraction;
74	exp2 = b.parts.exp;	80	exp2 = b.parts.exp;
75	};	81	};
76		82
77	if (exp1 == 0) {	83	if (exp1 == 0) {
78	/* both are denormalized */	84	/* both are denormalized */
79	frac1 += frac2;	85	frac1 += frac2;
80	if (frac1 & FLOAT32_HIDDEN_BIT_MASK ) {	86	if (frac1 & FLOAT32_HIDDEN_BIT_MASK ) {
81	/* result is not denormalized */	87	/* result is not denormalized */
82	a.parts.exp = 1;	88	a.parts.exp = 1;
83	};	89	};
84	a.parts.fraction = frac1;	90	a.parts.fraction = frac1;
85	return a;	91	return a;
86	};	92	};
87		93
88	frac1 \|= FLOAT32_HIDDEN_BIT_MASK; /* add hidden bit */	94	frac1 \|= FLOAT32_HIDDEN_BIT_MASK; /* add hidden bit */
89		95
90	if (exp2 == 0) {	96	if (exp2 == 0) {
91	/* second operand is denormalized */	97	/* second operand is denormalized */
92	--expdiff;	98	--expdiff;
93	} else {	99	} else {
94	/* add hidden bit to second operand */	100	/* add hidden bit to second operand */
95	frac2 \|= FLOAT32_HIDDEN_BIT_MASK;	101	frac2 \|= FLOAT32_HIDDEN_BIT_MASK;
96	};	102	};
97		103
98	/* create some space for rounding */	104	/* create some space for rounding */
99	frac1 <<= 6;	105	frac1 <<= 6;
100	frac2 <<= 6;	106	frac2 <<= 6;
101		107
102	if (expdiff < (FLOAT32_FRACTION_SIZE + 2) ) {	108	if (expdiff < (FLOAT32_FRACTION_SIZE + 2) ) {
103	frac2 >>= expdiff;	109	frac2 >>= expdiff;
104	frac1 += frac2;	110	frac1 += frac2;
105	} else {	111	} else {
106	a.parts.exp = exp1;	112	a.parts.exp = exp1;
107	a.parts.fraction = (frac1 >> 6) & (~(FLOAT32_HIDDEN_BIT_MASK));	113	a.parts.fraction = (frac1 >> 6) & (~(FLOAT32_HIDDEN_BIT_MASK));
108	return a;	114	return a;
109	}	115	}
110		116
111	if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {	117	if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {
112	++exp1;	118	++exp1;
113	frac1 >>= 1;	119	frac1 >>= 1;
114	};	120	};
115		121
116	/* rounding - if first bit after fraction is set then round up */	122	/* rounding - if first bit after fraction is set then round up */
117	frac1 += (0x1 << 5);	123	frac1 += (0x1 << 5);
118		124
119	if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {	125	if (frac1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {
120	/* rounding overflow */	126	/* rounding overflow */
121	++exp1;	127	++exp1;
122	frac1 >>= 1;	128	frac1 >>= 1;
123	};	129	};
124		130
125		131
126	if ((exp1 == FLOAT32_MAX_EXPONENT ) \|\| (exp2 > exp1)) {	132	if ((exp1 == FLOAT32_MAX_EXPONENT ) \|\| (exp2 > exp1)) {
127	/* overflow - set infinity as result */	133	/* overflow - set infinity as result */
128	a.parts.exp = FLOAT32_MAX_EXPONENT;	134	a.parts.exp = FLOAT32_MAX_EXPONENT;
129	a.parts.fraction = 0;	135	a.parts.fraction = 0;
130	return a;	136	return a;
131	}	137	}
132		138
133	a.parts.exp = exp1;	139	a.parts.exp = exp1;
134		140
135	/Clear hidden bit and shift /	141	/Clear hidden bit and shift /
136	a.parts.fraction = ((frac1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;	142	a.parts.fraction = ((frac1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;
137	return a;	143	return a;
138	}	144	}
139		145
140		146
141	/** Add two Float64 numbers with same signs	147	/** Add two Float64 numbers with same signs
142	*/	148	*/
143	float64 addFloat64(float64 a, float64 b)	149	float64 addFloat64(float64 a, float64 b)
144	{	150	{
145	int expdiff;	151	int expdiff;
146	uint32_t exp1, exp2;	152	uint32_t exp1, exp2;
147	uint64_t frac1, frac2;	153	uint64_t frac1, frac2;
148		154
149	expdiff = ((int )a.parts.exp) - b.parts.exp;	155	expdiff = ((int )a.parts.exp) - b.parts.exp;
150	if (expdiff < 0) {	156	if (expdiff < 0) {
151	if (isFloat64NaN(b)) {	157	if (isFloat64NaN(b)) {
152	/* TODO: fix SigNaN */	158	/* TODO: fix SigNaN */
153	if (isFloat64SigNaN(b)) {	159	if (isFloat64SigNaN(b)) {
154	};	160	};
155		161
156	return b;	162	return b;
157	};	163	};
158		164
159	/* b is infinity and a not */	165	/* b is infinity and a not */
160	if (b.parts.exp == FLOAT64_MAX_EXPONENT ) {	166	if (b.parts.exp == FLOAT64_MAX_EXPONENT ) {
161	return b;	167	return b;
162	}	168	}
163		169
164	frac1 = b.parts.fraction;	170	frac1 = b.parts.fraction;
165	exp1 = b.parts.exp;	171	exp1 = b.parts.exp;
166	frac2 = a.parts.fraction;	172	frac2 = a.parts.fraction;
167	exp2 = a.parts.exp;	173	exp2 = a.parts.exp;
168	expdiff *= -1;	174	expdiff *= -1;
169	} else {	175	} else {
170	if (isFloat64NaN(a)) {	176	if (isFloat64NaN(a)) {
171	/* TODO: fix SigNaN */	177	/* TODO: fix SigNaN */
172	if (isFloat64SigNaN(a) \|\| isFloat64SigNaN(b)) {	178	if (isFloat64SigNaN(a) \|\| isFloat64SigNaN(b)) {
173	};	179	};
174	return a;	180	return a;
175	};	181	};
176		182
177	/* a is infinity and b not */	183	/* a is infinity and b not */
178	if (a.parts.exp == FLOAT64_MAX_EXPONENT ) {	184	if (a.parts.exp == FLOAT64_MAX_EXPONENT ) {
179	return a;	185	return a;
180	}	186	}
181		187
182	frac1 = a.parts.fraction;	188	frac1 = a.parts.fraction;
183	exp1 = a.parts.exp;	189	exp1 = a.parts.exp;
184	frac2 = b.parts.fraction;	190	frac2 = b.parts.fraction;
185	exp2 = b.parts.exp;	191	exp2 = b.parts.exp;
186	};	192	};
187		193
188	if (exp1 == 0) {	194	if (exp1 == 0) {
189	/* both are denormalized */	195	/* both are denormalized */
190	frac1 += frac2;	196	frac1 += frac2;
191	if (frac1 & FLOAT64_HIDDEN_BIT_MASK) {	197	if (frac1 & FLOAT64_HIDDEN_BIT_MASK) {
192	/* result is not denormalized */	198	/* result is not denormalized */
193	a.parts.exp = 1;	199	a.parts.exp = 1;
194	};	200	};
195	a.parts.fraction = frac1;	201	a.parts.fraction = frac1;
196	return a;	202	return a;
197	};	203	};
198		204
199	/* add hidden bit - frac1 is sure not denormalized */	205	/* add hidden bit - frac1 is sure not denormalized */
200	frac1 \|= FLOAT64_HIDDEN_BIT_MASK;	206	frac1 \|= FLOAT64_HIDDEN_BIT_MASK;
201		207
202	/* second operand ... */	208	/* second operand ... */
203	if (exp2 == 0) {	209	if (exp2 == 0) {
204	/* ... is denormalized */	210	/* ... is denormalized */
205	--expdiff;	211	--expdiff;
206	} else {	212	} else {
207	/* is not denormalized */	213	/* is not denormalized */
208	frac2 \|= FLOAT64_HIDDEN_BIT_MASK;	214	frac2 \|= FLOAT64_HIDDEN_BIT_MASK;
209	};	215	};
210		216
211	/* create some space for rounding */	217	/* create some space for rounding */
212	frac1 <<= 6;	218	frac1 <<= 6;
213	frac2 <<= 6;	219	frac2 <<= 6;
214		220
215	if (expdiff < (FLOAT64_FRACTION_SIZE + 2) ) {	221	if (expdiff < (FLOAT64_FRACTION_SIZE + 2) ) {
216	frac2 >>= expdiff;	222	frac2 >>= expdiff;
217	frac1 += frac2;	223	frac1 += frac2;
218	} else {	224	} else {
219	a.parts.exp = exp1;	225	a.parts.exp = exp1;
220	a.parts.fraction = (frac1 >> 6) & (~(FLOAT64_HIDDEN_BIT_MASK));	226	a.parts.fraction = (frac1 >> 6) & (~(FLOAT64_HIDDEN_BIT_MASK));
221	return a;	227	return a;
222	}	228	}
223		229
224	if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {	230	if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {
225	++exp1;	231	++exp1;
226	frac1 >>= 1;	232	frac1 >>= 1;
227	};	233	};
228		234
229	/* rounding - if first bit after fraction is set then round up */	235	/* rounding - if first bit after fraction is set then round up */
230	frac1 += (0x1 << 5);	236	frac1 += (0x1 << 5);
231		237
232	if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {	238	if (frac1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {
233	/* rounding overflow */	239	/* rounding overflow */
234	++exp1;	240	++exp1;
235	frac1 >>= 1;	241	frac1 >>= 1;
236	};	242	};
237		243
238	if ((exp1 == FLOAT64_MAX_EXPONENT ) \|\| (exp2 > exp1)) {	244	if ((exp1 == FLOAT64_MAX_EXPONENT ) \|\| (exp2 > exp1)) {
239	/* overflow - set infinity as result */	245	/* overflow - set infinity as result */
240	a.parts.exp = FLOAT64_MAX_EXPONENT;	246	a.parts.exp = FLOAT64_MAX_EXPONENT;
241	a.parts.fraction = 0;	247	a.parts.fraction = 0;
242	return a;	248	return a;
243	}	249	}
244		250
245	a.parts.exp = exp1;	251	a.parts.exp = exp1;
246	/Clear hidden bit and shift /	252	/Clear hidden bit and shift /
247	a.parts.fraction = ( (frac1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));	253	a.parts.fraction = ( (frac1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));
248		254
249	return a;	255	return a;
250	}	256	}
251		257
252		258
-		259
-		260	/** @}
-		261	*/
-		262
253		263

Subversion Repositories HelenOS-historic

(root)/uspace/trunk/softfloat/generic/add.c – Rev 1031 → 1657