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| Rev 731 | Rev 804 | ||
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| 30 | #include<add.h> |
30 | #include<add.h> |
| 31 | #include<comparison.h> |
31 | #include<comparison.h> |
| 32 | 32 | ||
| 33 | float32 divFloat32(float32 a, float32 b) |
33 | float32 divFloat32(float32 a, float32 b) |
| 34 | { |
34 | { |
| 35 | /* TODO: */ |
35 | float32 result; |
| - | 36 | __s32 aexp, bexp, cexp; |
|
| - | 37 | __u64 afrac, bfrac, cfrac; |
|
| 36 | 38 | ||
| - | 39 | result.parts.sign = a.parts.sign ^ b.parts.sign; |
|
| - | 40 | ||
| - | 41 | if (isFloat32NaN(a)) { |
|
| - | 42 | if (isFloat32SigNaN(a)) { |
|
| - | 43 | /*FIXME: SigNaN*/ |
|
| - | 44 | } |
|
| - | 45 | /*NaN*/ |
|
| - | 46 | return a; |
|
| - | 47 | } |
|
| - | 48 | ||
| - | 49 | if (isFloat32NaN(b)) { |
|
| - | 50 | if (isFloat32SigNaN(b)) { |
|
| - | 51 | /*FIXME: SigNaN*/ |
|
| - | 52 | } |
|
| - | 53 | /*NaN*/ |
|
| - | 54 | return b; |
|
| - | 55 | } |
|
| - | 56 | ||
| - | 57 | if (isFloat32Infinity(a)) { |
|
| - | 58 | if (isFloat32Infinity(b)) { |
|
| - | 59 | /*FIXME: inf / inf */ |
|
| - | 60 | result.binary = FLOAT32_NAN; |
|
| - | 61 | return result; |
|
| - | 62 | } |
|
| - | 63 | /* inf / num */ |
|
| - | 64 | result.parts.exp = a.parts.exp; |
|
| - | 65 | result.parts.fraction = a.parts.fraction; |
|
| - | 66 | return result; |
|
| - | 67 | } |
|
| - | 68 | ||
| - | 69 | if (isFloat32Infinity(b)) { |
|
| - | 70 | if (isFloat32Zero(a)) { |
|
| - | 71 | /* FIXME 0 / inf */ |
|
| - | 72 | result.parts.exp = 0; |
|
| - | 73 | result.parts.fraction = 0; |
|
| - | 74 | return result; |
|
| - | 75 | } |
|
| - | 76 | /* FIXME: num / inf*/ |
|
| - | 77 | result.parts.exp = 0; |
|
| - | 78 | result.parts.fraction = 0; |
|
| - | 79 | return result; |
|
| - | 80 | } |
|
| - | 81 | ||
| - | 82 | if (isFloat32Zero(b)) { |
|
| - | 83 | if (isFloat32Zero(a)) { |
|
| - | 84 | /*FIXME: 0 / 0*/ |
|
| - | 85 | result.binary = FLOAT32_NAN; |
|
| - | 86 | return result; |
|
| - | 87 | } |
|
| - | 88 | /* FIXME: division by zero */ |
|
| - | 89 | result.parts.exp = 0; |
|
| - | 90 | result.parts.fraction = 0; |
|
| - | 91 | return result; |
|
| - | 92 | } |
|
| - | 93 | ||
| - | 94 | ||
| - | 95 | afrac = a.parts.fraction; |
|
| - | 96 | aexp = a.parts.exp; |
|
| - | 97 | bfrac = b.parts.fraction; |
|
| - | 98 | bexp = b.parts.exp; |
|
| - | 99 | ||
| - | 100 | /* denormalized numbers */ |
|
| - | 101 | if (aexp == 0) { |
|
| - | 102 | if (afrac == 0) { |
|
| - | 103 | result.parts.exp = 0; |
|
| - | 104 | result.parts.fraction = 0; |
|
| - | 105 | return result; |
|
| - | 106 | } |
|
| - | 107 | /* normalize it*/ |
|
| - | 108 | ||
| - | 109 | afrac <<= 1; |
|
| - | 110 | /* afrac is nonzero => it must stop */ |
|
| - | 111 | while (! (afrac & FLOAT32_HIDDEN_BIT_MASK) ) { |
|
| - | 112 | afrac <<= 1; |
|
| - | 113 | aexp--; |
|
| - | 114 | } |
|
| - | 115 | } |
|
| - | 116 | ||
| - | 117 | if (bexp == 0) { |
|
| - | 118 | bfrac <<= 1; |
|
| - | 119 | /* bfrac is nonzero => it must stop */ |
|
| - | 120 | while (! (bfrac & FLOAT32_HIDDEN_BIT_MASK) ) { |
|
| - | 121 | bfrac <<= 1; |
|
| - | 122 | bexp--; |
|
| - | 123 | } |
|
| - | 124 | } |
|
| - | 125 | ||
| - | 126 | afrac = (afrac | FLOAT32_HIDDEN_BIT_MASK ) << (32 - FLOAT32_FRACTION_SIZE - 1 ); |
|
| - | 127 | bfrac = (bfrac | FLOAT32_HIDDEN_BIT_MASK ) << (32 - FLOAT32_FRACTION_SIZE ); |
|
| - | 128 | ||
| - | 129 | if ( bfrac <= (afrac << 1) ) { |
|
| - | 130 | afrac >>= 1; |
|
| - | 131 | aexp++; |
|
| - | 132 | } |
|
| - | 133 | ||
| - | 134 | cexp = aexp - bexp + FLOAT32_BIAS - 2; |
|
| - | 135 | ||
| - | 136 | cfrac = (afrac << 32) / bfrac; |
|
| - | 137 | if (( cfrac & 0x3F ) == 0) { |
|
| - | 138 | cfrac |= ( bfrac * cfrac != afrac << 32 ); |
|
| - | 139 | } |
|
| - | 140 | ||
| - | 141 | /* pack and round */ |
|
| - | 142 | ||
| - | 143 | /* TODO: find first nonzero digit and shift result and detect possibly underflow */ |
|
| - | 144 | while ((cexp > 0) && (cfrac) && (!(cfrac & (FLOAT32_HIDDEN_BIT_MASK << 7 )))) { |
|
| - | 145 | cexp--; |
|
| - | 146 | cfrac <<= 1; |
|
| - | 147 | /* TODO: fix underflow */ |
|
| - | 148 | }; |
|
| - | 149 | ||
| - | 150 | ||
| - | 151 | cfrac += (0x1 << 6); /* FIXME: 7 is not sure*/ |
|
| - | 152 | ||
| - | 153 | if (cfrac & (FLOAT32_HIDDEN_BIT_MASK << 7)) { |
|
| - | 154 | ++cexp; |
|
| - | 155 | cfrac >>= 1; |
|
| - | 156 | } |
|
| - | 157 | ||
| - | 158 | /* check overflow */ |
|
| - | 159 | if (cexp >= FLOAT32_MAX_EXPONENT ) { |
|
| - | 160 | /* FIXME: overflow, return infinity */ |
|
| - | 161 | result.parts.exp = FLOAT32_MAX_EXPONENT; |
|
| - | 162 | result.parts.fraction = 0; |
|
| - | 163 | return result; |
|
| - | 164 | } |
|
| - | 165 | ||
| - | 166 | if (cexp < 0) { |
|
| - | 167 | /* FIXME: underflow */ |
|
| - | 168 | result.parts.exp = 0; |
|
| - | 169 | if ((cexp + FLOAT32_FRACTION_SIZE) < 0) { |
|
| - | 170 | result.parts.fraction = 0; |
|
| - | 171 | return result; |
|
| - | 172 | } |
|
| - | 173 | cfrac >>= 1; |
|
| - | 174 | while (cexp < 0) { |
|
| - | 175 | cexp ++; |
|
| - | 176 | cfrac >>= 1; |
|
| - | 177 | } |
|
| - | 178 | ||
| - | 179 | } else { |
|
| - | 180 | result.parts.exp = (__u32)cexp; |
|
| - | 181 | } |
|
| - | 182 | ||
| - | 183 | result.parts.fraction = ((cfrac >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)); |
|
| - | 184 | ||
| - | 185 | return result; |
|
| 37 | } |
186 | } |
| 38 | 187 | ||