25  *	the interval [0,0.34658]:
34  *      We use a special Reme algorithm on [0,0.347] to generate
79  *	  (ii)  if k=0, return r-E
90  *	for finite argument, only expm1(0)=0 is exact.
115 o_threshold	= 7.09782712893383973096e+02,/* 0x40862E42, 0xFEFA39EF */
116 ln2_hi		= 6.93147180369123816490e-01,/* 0x3fe62e42, 0xfee00000 */
117 ln2_lo		= 1.90821492927058770002e-10,/* 0x3dea39ef, 0x35793c76 */
118 invln2		= 1.44269504088896338700e+00,/* 0x3ff71547, 0x652b82fe */
136 	xsb = hx&0x80000000;		/* sign bit of x */  in expm1()
137 	hx &= 0x7fffffff;		/* high word of |x| */  in expm1()
140 	if(hx >= 0x4043687A) {			/* if |x|>=56*ln2 */  in expm1()
141 	    if(hx >= 0x40862E42) {		/* if |x|>=709.78... */  in expm1()
142                 if(hx>=0x7ff00000) {  in expm1()
145 		    if(((hx&0xfffff)|low)!=0)  in expm1()
147 		    else return (xsb==0)? x:-1.0;/* exp(+-inf)={inf,-1} */  in expm1()
151 	    if(xsb!=0) { /* x < -56*ln2, return -1.0 with inexact */  in expm1()
158 	if(hx > 0x3fd62e42) {		/* if  |x| > 0.5 ln2 */  in expm1()
159 	    if(hx < 0x3FF0A2B2) {	/* and |x| < 1.5 ln2 */  in expm1()
160 		if(xsb==0)  in expm1()
165 		k  = invln2*x+((xsb==0)?0.5:-0.5);  in expm1()
173 	else if(hx < 0x3c900000) {  	/* when |x|<2**-54, return x */  in expm1()
174 	    t = huge+x;	/* return x with inexact flags when x!=0 */  in expm1()
177 	else k = 0;  in expm1()
185 	if(k==0) return x - (x*e-hxs);		/* c is 0 */  in expm1()
187 	    INSERT_WORDS(twopk,((u_int32_t)(0x3ff+k))<<20,0);	/* 2^k */  in expm1()
197 		if (k == 1024) y = y*2.0*0x1p1023;  in expm1()
203 	        SET_HIGH_WORD(t,0x3ff00000 - (0x200000>>k));  /* t=1-2^-k */  in expm1()
207 		SET_HIGH_WORD(t,((0x3ff-k)<<20));	/* 2^-k */  in expm1()