return -two54/zero;              if (hx<0) return (x-x)/zero;
return -two54/(x-x);		 if (hx<0) return (x-x)/(x-x);
	double __ieee754_log10(double x)#else	double __ieee754_log10(x)	double x;#endif{	double y,z;	int32_t i,k,hx;	u_int32_t lx;	EXTRACT_WORDS(hx,lx,x);        k=0;        if (hx < 0x00100000) {                  /* x < 2**-1022  */            if (((hx&0x7fffffff)|lx)==0)                return -two54/zero;             /* 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;	i  = ((u_int32_t)k&0x80000000)>>31;        hx = (hx&0x000fffff)|((0x3ff-i)<<20);        y  = (double)(k+i);	SET_HIGH_WORD(x,hx);	z  = y*log10_2lo + ivln10*__ieee754_log(x);	return  z+y*log10_2hi;}