32,7 → 32,156 |
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float32 divFloat32(float32 a, float32 b) |
{ |
/* TODO: */ |
float32 result; |
__s32 aexp, bexp, cexp; |
__u64 afrac, bfrac, cfrac; |
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result.parts.sign = a.parts.sign ^ b.parts.sign; |
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if (isFloat32NaN(a)) { |
if (isFloat32SigNaN(a)) { |
/*FIXME: SigNaN*/ |
} |
/*NaN*/ |
return a; |
} |
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if (isFloat32NaN(b)) { |
if (isFloat32SigNaN(b)) { |
/*FIXME: SigNaN*/ |
} |
/*NaN*/ |
return b; |
} |
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if (isFloat32Infinity(a)) { |
if (isFloat32Infinity(b)) { |
/*FIXME: inf / inf */ |
result.binary = FLOAT32_NAN; |
return result; |
} |
/* inf / num */ |
result.parts.exp = a.parts.exp; |
result.parts.fraction = a.parts.fraction; |
return result; |
} |
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if (isFloat32Infinity(b)) { |
if (isFloat32Zero(a)) { |
/* FIXME 0 / inf */ |
result.parts.exp = 0; |
result.parts.fraction = 0; |
return result; |
} |
/* FIXME: num / inf*/ |
result.parts.exp = 0; |
result.parts.fraction = 0; |
return result; |
} |
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if (isFloat32Zero(b)) { |
if (isFloat32Zero(a)) { |
/*FIXME: 0 / 0*/ |
result.binary = FLOAT32_NAN; |
return result; |
} |
/* FIXME: division by zero */ |
result.parts.exp = 0; |
result.parts.fraction = 0; |
return result; |
} |
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afrac = a.parts.fraction; |
aexp = a.parts.exp; |
bfrac = b.parts.fraction; |
bexp = b.parts.exp; |
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/* denormalized numbers */ |
if (aexp == 0) { |
if (afrac == 0) { |
result.parts.exp = 0; |
result.parts.fraction = 0; |
return result; |
} |
/* normalize it*/ |
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afrac <<= 1; |
/* afrac is nonzero => it must stop */ |
while (! (afrac & FLOAT32_HIDDEN_BIT_MASK) ) { |
afrac <<= 1; |
aexp--; |
} |
} |
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if (bexp == 0) { |
bfrac <<= 1; |
/* bfrac is nonzero => it must stop */ |
while (! (bfrac & FLOAT32_HIDDEN_BIT_MASK) ) { |
bfrac <<= 1; |
bexp--; |
} |
} |
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afrac = (afrac | FLOAT32_HIDDEN_BIT_MASK ) << (32 - FLOAT32_FRACTION_SIZE - 1 ); |
bfrac = (bfrac | FLOAT32_HIDDEN_BIT_MASK ) << (32 - FLOAT32_FRACTION_SIZE ); |
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if ( bfrac <= (afrac << 1) ) { |
afrac >>= 1; |
aexp++; |
} |
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cexp = aexp - bexp + FLOAT32_BIAS - 2; |
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cfrac = (afrac << 32) / bfrac; |
if (( cfrac & 0x3F ) == 0) { |
cfrac |= ( bfrac * cfrac != afrac << 32 ); |
} |
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/* pack and round */ |
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/* TODO: find first nonzero digit and shift result and detect possibly underflow */ |
while ((cexp > 0) && (cfrac) && (!(cfrac & (FLOAT32_HIDDEN_BIT_MASK << 7 )))) { |
cexp--; |
cfrac <<= 1; |
/* TODO: fix underflow */ |
}; |
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cfrac += (0x1 << 6); /* FIXME: 7 is not sure*/ |
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if (cfrac & (FLOAT32_HIDDEN_BIT_MASK << 7)) { |
++cexp; |
cfrac >>= 1; |
} |
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/* check overflow */ |
if (cexp >= FLOAT32_MAX_EXPONENT ) { |
/* FIXME: overflow, return infinity */ |
result.parts.exp = FLOAT32_MAX_EXPONENT; |
result.parts.fraction = 0; |
return result; |
} |
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if (cexp < 0) { |
/* FIXME: underflow */ |
result.parts.exp = 0; |
if ((cexp + FLOAT32_FRACTION_SIZE) < 0) { |
result.parts.fraction = 0; |
return result; |
} |
cfrac >>= 1; |
while (cexp < 0) { |
cexp ++; |
cfrac >>= 1; |
} |
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} else { |
result.parts.exp = (__u32)cexp; |
} |
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result.parts.fraction = ((cfrac >> 6) & (~FLOAT32_HIDDEN_BIT_MASK)); |
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return result; |
} |
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