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Ignore whitespace Rev 543 → Rev 563

/uspace/trunk/softfloat/include/softfloat.h
34,35 → 34,35
float f;
struct {
#ifdef __BIG_ENDIAN__
__u8 sign:1;
__u8 exp:8;
__u32 sign:1;
__u32 exp:8;
__u32 mantisa:23;
#else
#ifdef __LITTLE_ENDIAN__
#elif defined __LITTLE_ENDIAN__
__u32 mantisa:23;
__u8 exp:8;
__u8 sign:1;
__u32 exp:8;
__u32 sign:1;
#else
#error "Unknown endians."
#endif
} parts __attribute__ ((packed));
} float32_t;
} float32;
typedef union {
double d;
struct {
#ifdef __BIG_ENDIAN__
__u8 sign:1;
__u8 exp:11;
__u32 mantisa:52;
#else
#ifdef __LITTLE_ENDIAN__
__u32 mantisa:52;
__u8 exp:11;
__u8 sign:1;
__u64 sign:1;
__u64 exp:11;
__u64 mantisa:52;
#elif defined __LITTLE_ENDIAN__
__u64 mantisa:52;
__u64 exp:11;
__u64 sign:1;
#else
#error "Unknown endians."
#endif
} parts __attribute__ ((packed));
} float64_t;
} float64;
 
#define FLOAT32_MAX 0x7f800000
#define FLOAT32_MIN 0xff800000
/uspace/trunk/softfloat/generic/softfloat.c
29,23 → 29,27
 
#include<softfloat.h>
 
float32 addFloat32(float32 a, float32 b);
float32 subFloat32(float32 a, float32 b);
inline int isFloat32NaN(float32 f);
inline int isFloat32SigNaN(float32 f);
 
float __addsf3(float a, float b)
{
float32 fa, fb;
a.f=a;
b.f=b;
if (a.parts.sign!=b.parts.sign) return subFloat32(a,b).f;
return addFloat32(a,b).f;
fa.f=a;
fb.f=b;
if (fa.parts.sign!=fb.parts.sign) return subFloat32(fa,fb).f;
return addFloat32(fa,fb).f;
};
 
float __subsf3(float a, float b)
{
float32 fa, fb;
a.f=a;
b.f=b;
if (a.parts.sign!=b.parts.sign) return addFloat32(a,b).f;
return subFloat32(a,b).f;
fa.f=a;
fb.f=b;
if (fa.parts.sign!=fb.parts.sign) return addFloat32(fa,fb).f;
return subFloat32(fa,fb).f;
};
 
float __negsf2(float a)
59,23 → 63,31
double __negdf2(double a)
{
float64 fa;
fa.f=a;
fa.d=a;
fa.parts.sign=!fa.parts.sign;
return fa.f;
return fa.d;
};
 
/** Add two Float32 numbers with same signs
*/
float32 addFloat32(float32 a, float32 b)
{
__u32 expdiff;
int expdiff;
__u32 exp1,exp2,mant1,mant2;
expdiff=a.parts.exp - b.parts.exp;
if (expdiff<0) {
if (isFloat32NaN(a)) {
//TODO: fix it
return a;
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;
82,24 → 94,40
exp2=a.parts.exp;
expdiff*=-1;
} else {
if (isFloat32NaN(b)) {
//TODO: fix it
return b;
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&0xF00000) {
a.parts.exp=1;
};
a.parts.mantisa=mant1;
return a;
};
// create some space for rounding
mant1<<=6;
mant2<<=6;
if (exp1!=0) {
mant1|=0x20000000; //add hidden bit
};
mant1|=0x20000000; //add hidden bit
if (exp2==0) {
--expdiff;
} else {
106,20 → 134,24
mant2|=0x20000000; //hidden bit
};
if (expdiff>24) {
goto done;
};
mant2>>=expdiff;
mant1+=mant2;
done:
//TODO: round mant1
if (mant1&0x40000000) {
++exp1;
mant1>>=1;
};
//rounding - if first bit after mantisa is set then round up
mant1+=0x20;
a.parts.exp=exp1;
a.parts.mantisa=mant1>>6;
return a;
};
 
/** Substract two float32 numbers with same signs
*/
float32 subFloat32(float32 a, float32 b)
{
128,15 → 160,11
 
inline int isFloat32NaN(float32 f)
{ /* NaN : exp = 0xff and nonzero mantisa */
float32 fa;
fa.f=f;
return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa));
return ((f.parts.exp==0xFF)&&(f.parts.mantisa));
};
 
inline int isFloat32SigNaN(float32 f)
{ /* SigNaN : exp = 0xff mantisa = 1xxxxx..x (binary), where at least one x is nonzero */
float32 fa;
fa.f=f;
return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa>0x400000));
return ((f.parts.exp==0xFF)&&(f.parts.mantisa>0x400000));
};