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731 cejka 1 
/*
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 * Copyright (C) 2005 Josef Cejka
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 *
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 * - Redistributions of source code must retain the above copyright
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 *   notice, this list of conditions and the following disclaimer.
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 * - Redistributions in binary form must reproduce the above copyright
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 *   notice, this list of conditions and the following disclaimer in the
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 *   documentation and/or other materials provided with the distribution.
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 * - The name of the author may not be used to endorse or promote products
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 *   derived from this software without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
28 
 
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#include<sftypes.h>
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#include<add.h>
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#include<comparison.h>
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/** Add two Float32 numbers with same signs
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 */
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float32 addFloat32(float32 a, float32 b)
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{
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	int expdiff;
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	__u32 exp1, exp2,mant1, mant2;
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732 cejka 40 
	expdiff = a.parts.exp - b.parts.exp;
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	if (expdiff < 0) {
731 cejka 42 
		if (isFloat32NaN(b)) {
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			//TODO: fix SigNaN
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			if (isFloat32SigNaN(b)) {
45 
			};
46 
 
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			return b;
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		};
49 
 
732 cejka 50 
		if (b.parts.exp == FLOAT32_MAX_EXPONENT) {
731 cejka 51 
			return b;
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		}
53 
 
732 cejka 54 
		mant1 = b.parts.mantisa;
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		exp1 = b.parts.exp;
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		mant2 = a.parts.mantisa;
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		exp2 = a.parts.exp;
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		expdiff *= -1;
731 cejka 59 
	} else {
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		if (isFloat32NaN(a)) {
61 
			//TODO: fix SigNaN
732 cejka 62 
			if (isFloat32SigNaN(a) || isFloat32SigNaN(b)) {
731 cejka 63 
			};
64 
			return a;
65 
		};
66 
 
732 cejka 67 
		if (a.parts.exp == FLOAT32_MAX_EXPONENT) {
731 cejka 68 
			return a;
69 
		}
70 
 
732 cejka 71 
		mant1 = a.parts.mantisa;
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		exp1 = a.parts.exp;
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		mant2 = b.parts.mantisa;
74 
		exp2 = b.parts.exp;
731 cejka 75 
	};
76 
 
77 
	if (exp1 == 0) {
78 
		/* both are denormalized */
79 
		mant1 += mant2;
80 
		if (mant1 & FLOAT32_HIDDEN_BIT_MASK ) {
81 
			/* result is not denormalized */
82 
			a.parts.exp = 1;
83 
		};
84 
		a.parts.mantisa = mant1;
85 
		return a;
86 
	};
87 
 
88 
	mant1 |= FLOAT32_HIDDEN_BIT_MASK; //add hidden bit
89 
 
90 
	if (exp2 == 0) {
91 
		/* second operand is denormalized */
92 
		--expdiff;
93 
	} else {
94 
		/* add hidden bit to second operand */
95 
		mant2 |= FLOAT32_HIDDEN_BIT_MASK;
96 
	};
97 
 
98 
	/* create some space for rounding */
99 
	mant1 <<= 6;
100 
	mant2 <<= 6;
101 
 
732 cejka 102 
	if (expdiff > (FLOAT32_MANTISA_SIZE + 1) ) {
731 cejka 103 
	     goto done;
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	     };
105 
 
732 cejka 106 
	mant2 >>= expdiff;
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	mant1 += mant2;
731 cejka 108 
done:
732 cejka 109 
	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7) ) {
731 cejka 110 
		++exp1;
111 
		mant1 >>= 1;
112 
	};
113 
 
114 
	/* rounding - if first bit after mantisa is set then round up */
115 
	mant1 += (0x1 << 5);
116 
 
732 cejka 117 
	if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 7)) {
731 cejka 118 
		++exp1;
732 cejka 119 
		mant1 >>= 1;
731 cejka 120 
	};
121 
 
122 
	a.parts.exp = exp1;
123 
 
124 
	/*Clear hidden bit and shift */
732 cejka 125 
	a.parts.mantisa = ((mant1 >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)) ;
731 cejka 126 
	return a;
127 
}
128 
 
129 
 
130 
/** Add two Float64 numbers with same signs
131 
 */
132 
float64 addFloat64(float64 a, float64 b)
133 
{
134 
	int expdiff;
732 cejka 135 
	__u64 exp1, exp2, mant1, mant2;
731 cejka 136 
 
732 cejka 137 
	expdiff = a.parts.exp - b.parts.exp;
138 
	if (expdiff < 0) {
731 cejka 139 
		if (isFloat64NaN(b)) {
140 
			//TODO: fix SigNaN
141 
			if (isFloat64SigNaN(b)) {
142 
			};
143 
 
144 
			return b;
145 
		};
146 
 
147 
		/* b is infinity and a not */
732 cejka 148 
		if (b.parts.exp == FLOAT64_MAX_EXPONENT ) {
731 cejka 149 
			return b;
150 
		}
151 
 
732 cejka 152 
		mant1 = b.parts.mantisa;
153 
		exp1 = b.parts.exp;
154 
		mant2 = a.parts.mantisa;
155 
		exp2 = a.parts.exp;
156 
		expdiff *= -1;
731 cejka 157 
	} else {
158 
		if (isFloat64NaN(a)) {
159 
			//TODO: fix SigNaN
732 cejka 160 
			if (isFloat64SigNaN(a) || isFloat64SigNaN(b)) {
731 cejka 161 
			};
162 
			return a;
163 
		};
164 
 
165 
		/* a is infinity and b not */
732 cejka 166 
		if (a.parts.exp == FLOAT64_MAX_EXPONENT ) {
731 cejka 167 
			return a;
168 
		}
169 
 
170 
		mant1 = a.parts.mantisa;
171 
		exp1 = a.parts.exp;
172 
		mant2 = b.parts.mantisa;
173 
		exp2 = b.parts.exp;
174 
	};
175 
 
176 
	if (exp1 == 0) {
177 
		/* both are denormalized */
178 
		mant1 += mant2;
179 
		if (mant1 & FLOAT64_HIDDEN_BIT_MASK) {
180 
			/* result is not denormalized */
181 
			a.parts.exp = 1;
182 
		};
183 
		a.parts.mantisa = mant1;
184 
		return a;
185 
	};
186 
 
187 
	/* add hidden bit - mant1 is sure not denormalized */
188 
	mant1 |= FLOAT64_HIDDEN_BIT_MASK;
189 
 
190 
	/* second operand ... */
191 
	if (exp2 == 0) {
192 
		/* ... is denormalized */
193 
		--expdiff;
194 
	} else {
195 
		/* is not denormalized */
196 
		mant2 |= FLOAT64_HIDDEN_BIT_MASK;
197 
	};
198 
 
199 
	/* create some space for rounding */
200 
	mant1 <<= 6;
201 
	mant2 <<= 6;
202 
 
732 cejka 203 
	if (expdiff > (FLOAT64_MANTISA_SIZE + 1) ) {
731 cejka 204 
	     goto done;
205 
	     };
206 
 
207 
	mant2 >>= expdiff;
208 
	mant1 += mant2;
209 
done:
732 cejka 210 
	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7) ) {
731 cejka 211 
		++exp1;
212 
		mant1 >>= 1;
213 
	};
214 
 
215 
	/* rounding - if first bit after mantisa is set then round up */
216 
	mant1 += (0x1 << 5);
217 
 
732 cejka 218 
	if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 7)) {
731 cejka 219 
		++exp1;
732 cejka 220 
		mant1 >>= 1;
731 cejka 221 
	};
222 
 
223 
	a.parts.exp = exp1;
224 
	/*Clear hidden bit and shift */
732 cejka 225 
	a.parts.mantisa = ( (mant1 >> 6 ) & (~FLOAT64_HIDDEN_BIT_MASK));
731 cejka 226 
	return a;
227 
}
228 
 
229