0,0 → 1,229 |
/* |
* 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==0xFF) { |
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==0xFF) { |
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 > 24) { |
goto done; |
}; |
|
mant2>>=expdiff; |
mant1+=mant2; |
done: |
if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 6) ) { |
++exp1; |
mant1 >>= 1; |
}; |
|
/* rounding - if first bit after mantisa is set then round up */ |
mant1 += (0x1 << 5); |
|
if (mant1 & (FLOAT32_HIDDEN_BIT_MASK << 6)) { |
++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==0x8FF) { |
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 == 0x8FF) { |
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 > 53) { |
goto done; |
}; |
|
mant2 >>= expdiff; |
mant1 += mant2; |
done: |
if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 6) ) { |
++exp1; |
mant1 >>= 1; |
}; |
|
/* rounding - if first bit after mantisa is set then round up */ |
mant1 += (0x1 << 5); |
|
if (mant1 & (FLOAT64_HIDDEN_BIT_MASK << 6)) { |
++exp1; |
mant1 >> =1; |
}; |
|
a.parts.exp = exp1; |
/*Clear hidden bit and shift */ |
a.parts.mantisa = ( (mant1 >>6 ) & (~ (FLOAT64_HIDDEN_BIT_MASK))); |
return a; |
} |
|
|