1 /*-
17 static const double Zero[] = {0.0, -0.0,};
23  * a side-effect of computing the remainder by the shift and subtract
35 	sxy = (hx ^ hy) & 0x80000000;  in remquo()
36 	sx = hx&0x80000000;		/* sign of x */  in remquo()
38 	hy &= 0x7fffffff;	/* |y| */  in remquo()
41 	if((hy|ly)==0||(hx>=0x7ff00000)||	/* y=0,or x not finite */  in remquo()
42 	  ((hy|((ly|-ly)>>31))>0x7ff00000))	/* or y is NaN */  in remquo()
46 		q = 0;  in remquo()
47 		goto fixup;	/* |x|<|y| return x or x-y */  in remquo()
50 		*quo = (sxy ? -1 : 1);  in remquo()
51 		return Zero[(u_int32_t)sx>>31];	/* |x|=|y| return x*0*/  in remquo()
56 	if(hx<0x00100000)  in remquo()
59 	    ix = (hx>>20)-1023;  in remquo()
62 	if(hy<0x00100000)  in remquo()
65 	    iy = (hy>>20)-1023;  in remquo()
68 	if(ix >= -1022)  in remquo()
69 	    hx = 0x00100000|(0x000fffff&hx);  in remquo()
71 	    n = -1022-ix;  in remquo()
73 	        hx = (hx<<n)|(lx>>(32-n));  in remquo()
76 		hx = lx<<(n-32);  in remquo()
77 		lx = 0;  in remquo()
80 	if(iy >= -1022)  in remquo()
81 	    hy = 0x00100000|(0x000fffff&hy);  in remquo()
83 	    n = -1022-iy;  in remquo()
85 	        hy = (hy<<n)|(ly>>(32-n));  in remquo()
88 		hy = ly<<(n-32);  in remquo()
89 		ly = 0;  in remquo()
94 	n = ix - iy;  in remquo()
95 	q = 0;  in remquo()
96 	while(n--) {  in remquo()
97 	    hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;  in remquo()
98 	    if(hz<0){hx = hx+hx+(lx>>31); lx = lx+lx;}  in remquo()
102 	hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;  in remquo()
103 	if(hz>=0) {hx=hz;lx=lz;q++;}  in remquo()
106 	if((hx|lx)==0) {			/* return sign(x)*0 */  in remquo()
107 	    q &= 0x7fffffff;  in remquo()
108 	    *quo = (sxy ? -q : q);  in remquo()
111 	while(hx<0x00100000) {		/* normalize x */  in remquo()
113 	    iy -= 1;  in remquo()
115 	if(iy>= -1022) {	/* normalize output */  in remquo()
116 	    hx = ((hx-0x00100000)|((iy+1023)<<20));  in remquo()
118 	    n = -1022 - iy;  in remquo()
120 		lx = (lx>>n)|((u_int32_t)hx<<(32-n));  in remquo()
123 		lx = (hx<<(32-n))|(lx>>n); hx = 0;  in remquo()
125 		lx = hx>>(n-32); hx = 0;  in remquo()
131 	if (y < 0x1p-1021) {  in remquo()
134 		x-=y;  in remquo()
138 	    x-=y;  in remquo()
142 	q &= 0x7fffffff;  in remquo()
143 	*quo = (sxy ? -q : q);  in remquo()