Index: softfloat/generic/arithmetic.c
===================================================================
--- softfloat/generic/arithmetic.c	(revision cf4a82392e2e531adcc4ea3efef573197358c03b)
+++ softfloat/generic/arithmetic.c	(revision 75a23abf38eb395f85ce0f89c937eea20ab2df7a)
@@ -112,15 +112,127 @@
 	mant1+=0x20;
 	
+	if (mant1&0x40000000) { 
+		++exp1;
+		mant1>>=1;
+	};
+	
 	a.parts.exp=exp1;
-	a.parts.mantisa=mant1>>6;
+	a.parts.mantisa = ((mant1&(~0x20000000))>>6); /*Clear hidden bit and shift */
 	return a;
 };
 
-/** Substract two float32 numbers with same signs
+/** Subtract two float32 numbers with same signs
  */
 float32 subFloat32(float32 a, float32 b)
 {
-	
-	
+	int expdiff;
+	__u32 exp1,exp2,mant1,mant2;
+	float32 result;
+
+	result.f = 0;
+	
+	expdiff=a.parts.exp - b.parts.exp;
+	if ((expdiff<0)||((expdiff==0)&&(a.parts.mantisa<b.parts.mantisa))) {
+		if (isFloat32NaN(b)) {
+			//TODO: fix SigNaN
+			if (isFloat32SigNaN(b)) {
+			};
+			return b;
+		};
+		
+		if (b.parts.exp==0xFF) { 
+			b.parts.sign=!b.parts.sign; /* num -(+-inf) = -+inf */
+			return b;
+		}
+		
+		result.parts.sign = !a.parts.sign; 
+		
+		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) { 
+			if (b.parts.exp==0xFF) {
+				/* inf - inf => nan */
+				//TODO: fix exception
+				result.binary = FLOAT32_NAN;
+				return result;
+			};
+			return a;
+		}
+		
+		result.parts.sign = a.parts.sign;
+		
+		mant1=a.parts.mantisa;
+		exp1=a.parts.exp;
+		mant2=b.parts.mantisa;
+		exp2=b.parts.exp;
+		
+
+		
+	};
+	
+	if (exp1==0) {
+		//both are denormalized
+		result.parts.mantisa=mant1-mant2;
+		if (result.parts.mantisa>mant1) {
+			//TODO: underflow exception
+			return result;
+		};
+		result.parts.exp=0;
+		return result;
+	};
+	
+	// create some space for rounding
+	mant1<<=6;
+	mant2<<=6;
+	
+	mant1|=0x20000000; //add hidden bit
+	
+	
+	if (exp2==0) {
+		--expdiff;	
+	} else {
+		mant2|=0x20000000; //hidden bit
+	};
+	
+	if (expdiff>24) {
+	     goto done;	
+	     };
+	
+	mant1 = mant1-(mant2>>expdiff);
+done:
+	
+	//TODO: find first nonzero digit and shift result and detect possibly underflow
+	while ((exp1>0)&&(!(mant1&0x20000000))) {
+		exp1--;
+		mant1 <<= 1;
+		if(mant1 == 0) {
+			/* Realy is it an underflow? ... */
+			//TODO: fix underflow
+		};
+	};
+	
+	//rounding - if first bit after mantisa is set then round up	
+	mant1 += 0x20;
+
+	if (mant1&0x40000000) {
+		++exp1;
+		mant1>>=1;
+	};
+	
+	result.parts.mantisa = ((mant1&(~0x20000000))>>6); /*Clear hidden bit and shift */
+	result.parts.exp = exp1;
+	
+	return result;
 };
 
Index: softfloat/include/sftypes.h
===================================================================
--- softfloat/include/sftypes.h	(revision cf4a82392e2e531adcc4ea3efef573197358c03b)
+++ softfloat/include/sftypes.h	(revision 75a23abf38eb395f85ce0f89c937eea20ab2df7a)
@@ -74,4 +74,9 @@
 #define FLOAT64_MIN
 
+/* For recognizing NaNs or infinity use isFloat32NaN and is Float32Inf, comparing with this constants is not sufficient */
+#define FLOAT32_NAN 0x7F800001
+#define FLOAT32_SIGNAN 0x7FC00000
+#define FLOAT32_INF 0x7F800000
+
 #define FLOAT32_BIAS 0xF7
 #define FLOAT64_BIAS 0x3FF