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/*
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/*
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 * Copyright (C) 2005 Josef Cejka
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 * Copyright (C) 2005 Josef Cejka
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 * All rights reserved.
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 * All rights reserved.
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 *
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 *
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 * Redistribution and use in source and binary forms, with or without
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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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 * modification, are permitted provided that the following conditions
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 * are met:
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 * are met:
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 *
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 *
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 * - Redistributions of source code must retain the above copyright
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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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 *   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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 * - 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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 *   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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 *   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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 * - 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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 *   derived from this software without specific prior written permission.
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 *
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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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 * 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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 * 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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 * 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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 * 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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 * 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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 * 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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 * 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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 * 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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 * (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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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
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 */
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#include<softfloat.h>
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#include<softfloat.h>
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- 
 
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- 
 
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float __addsf3(float a, float b)
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{
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    float32 fa, fb;
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    a.f=a;
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    b.f=b;
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    if (a.parts.sign!=b.parts.sign) return subFloat32(a,b).f;
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    return addFloat32(a,b).f;
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};
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float __subsf3(float a, float b)
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{
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    float32 fa, fb;
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    a.f=a;
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    b.f=b;
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    if (a.parts.sign!=b.parts.sign) return addFloat32(a,b).f;
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    return subFloat32(a,b).f;
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};
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float __negsf2(float a)
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{
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    float32 fa;
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    fa.f=a;
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    fa.parts.sign=!fa.parts.sign;
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    return fa.f;
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};
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double __negdf2(double a)
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{
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    float64 fa;
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    fa.f=a;
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    fa.parts.sign=!fa.parts.sign;
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    return fa.f;
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};
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float32 addFloat32(float32 a, float32 b)
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{
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    __u32 expdiff;
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    __u32 exp1,exp2,mant1,mant2;
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    expdiff=a.parts.exp - b.parts.exp;
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    if (expdiff<0) {
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        if (isFloat32NaN(a)) {
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            //TODO: fix it
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            return a;
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        };
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        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;
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    } else {
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        if (isFloat32NaN(b)) {
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            //TODO: fix it
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            return b;
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        };
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        mant1=a.parts.mantisa;
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        exp1=a.parts.exp;
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        mant2=b.parts.mantisa;
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        exp2=b.parts.exp;
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    };
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    // create some space for rounding
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    mant1<<=6;
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    mant2<<=6;
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    if (exp1!=0) {
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        mant1|=0x20000000; //add hidden bit
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    };
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    if (exp2==0) {
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        --expdiff; 
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    } else {
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        mant2|=0x20000000; //hidden bit
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    };
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    if (expdiff>24) {
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        goto done;
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    };
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    mant2>>=expdiff;
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    mant1+=mant2;
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done:
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    //TODO: round mant1
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    a.parts.exp=exp1;
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    a.parts.mantisa=mant1>>6;
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    return a;
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};
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float32 subFloat32(float32 a, float32 b)
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{
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};
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inline int isFloat32NaN(float32 f)
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{   /* NaN : exp = 0xff and nonzero mantisa */
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    float32 fa;
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    fa.f=f;
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    return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa));
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};
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inline int isFloat32SigNaN(float32 f)
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{   /* SigNaN : exp = 0xff mantisa = 1xxxxx..x (binary), where at least one x is nonzero */
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    float32 fa;
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    fa.f=f;
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    return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa>0x400000));
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};
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