Index: uspace/lib/math/generic/log.c
===================================================================
--- uspace/lib/math/generic/log.c	(revision ec6081ce7d2abd93fb37b71a801492678d8e0745)
+++ uspace/lib/math/generic/log.c	(revision f250c5ad6a76a78db608d678ea270ea17a01cbe0)
@@ -69,7 +69,11 @@
 #include <math.h>
 #include <stdint.h>
+
+#include "internal.h"
+
 static const double
-ln2_hi = 6.93147180369123816490e-01,  /* 3fe62e42 fee00000 */
-ln2_lo = 1.90821492927058770002e-10,  /* 3dea39ef 35793c76 */
+ln2_hi  =  6.93147180369123816490e-01,	/* 3fe62e42 fee00000 */
+ln2_lo  =  1.90821492927058770002e-10,	/* 3dea39ef 35793c76 */
+two54   =  1.80143985094819840000e+16,  /* 43500000 00000000 */
 Lg1 = 6.666666666666735130e-01,  /* 3FE55555 55555593 */
 Lg2 = 3.999999999940941908e-01,  /* 3FD99999 9997FA04 */
@@ -80,44 +84,62 @@
 Lg7 = 1.479819860511658591e-01;  /* 3FC2F112 DF3E5244 */
 
+static const double zero   =  0.0;
+static volatile double vzero = 0.0;
+
+
 double log(double x)
 {
-	union {double f; uint64_t i;} u = {x};
-	double_t hfsq,f,s,z,R,w,t1,t2,dk;
-	uint32_t hx;
-	int k;
-	hx = u.i>>32;
-	k = 0;
-	if (hx < 0x00100000 || hx>>31) {
-		if (u.i<<1 == 0)
-			return -1/(x*x);  /* log(+-0)=-inf */
-		if (hx>>31)
-			return (x-x)/0.0; /* log(-#) = NaN */
-		/* subnormal number, scale x up */
-		k -= 54;
-		x *= 0x1p54;
-		u.f = x;
-		hx = u.i>>32;
-	} else if (hx >= 0x7ff00000) {
-		return x;
-	} else if (hx == 0x3ff00000 && u.i<<32 == 0)
-		return 0;
+	double hfsq,f,s,z,R,w,t1,t2,dk;
+	int32_t k,hx,i,j;
+	uint32_t lx;
 
-	/* reduce x into [sqrt(2)/2, sqrt(2)] */
-	hx += 0x3ff00000 - 0x3fe6a09e;
-	k += (int)(hx>>20) - 0x3ff;
-	hx = (hx&0x000fffff) + 0x3fe6a09e;
-	u.i = (uint64_t)hx<<32 | (u.i&0xffffffff);
-	x = u.f;
-	f = x - 1.0;
-	hfsq = 0.5*f*f;
-	s = f/(2.0+f);
+	EXTRACT_WORDS(hx,lx,x);
+
+	k=0;
+	if (hx < 0x00100000) {			/* x < 2**-1022  */
+	    if (((hx&0x7fffffff)|lx)==0) 
+		return -two54/vzero;		/* log(+-0)=-inf */
+	    if (hx<0) return (x-x)/zero;	/* log(-#) = NaN */
+	    k -= 54; x *= two54; /* subnormal number, scale up x */
+	    GET_HIGH_WORD(hx,x);
+	} 
+	if (hx >= 0x7ff00000) return x+x;
+	k += (hx>>20)-1023;
+	hx &= 0x000fffff;
+	i = (hx+0x95f64)&0x100000;
+	SET_HIGH_WORD(x,hx|(i^0x3ff00000));	/* normalize x or x/2 */
+	k += (i>>20);
+	f = x-1.0;
+	if((0x000fffff&(2+hx))<3) {	/* -2**-20 <= f < 2**-20 */
+	    if(f==zero) {
+		if(k==0) {
+		    return zero;
+		} else {
+		    dk=(double)k;
+		    return dk*ln2_hi+dk*ln2_lo;
+		}
+	    }
+	    R = f*f*(0.5-0.33333333333333333*f);
+	    if(k==0) return f-R; else {dk=(double)k;
+	    	     return dk*ln2_hi-((R-dk*ln2_lo)-f);}
+	}
+ 	s = f/(2.0+f); 
+	dk = (double)k;
 	z = s*s;
+	i = hx-0x6147a;
 	w = z*z;
-	t1 = w*(Lg2+w*(Lg4+w*Lg6));
-	t2 = z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7)));
-	R = t2 + t1;
-	dk = k;
-
-	return s*(hfsq+R) + dk*ln2_lo - hfsq + f + dk*ln2_hi;
+	j = 0x6b851-hx;
+	t1= w*(Lg2+w*(Lg4+w*Lg6)); 
+	t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); 
+	i |= j;
+	R = t2+t1;
+	if(i>0) {
+	    hfsq=0.5*f*f;
+	    if(k==0) return f-(hfsq-s*(hfsq+R)); else
+		     return dk*ln2_hi-((hfsq-(s*(hfsq+R)+dk*ln2_lo))-f);
+	} else {
+	    if(k==0) return f-s*(f-R); else
+		     return dk*ln2_hi-((s*(f-R)-dk*ln2_lo)-f);
+	}
 }
 
