1 /* e_hypotf.c -- float version of e_hypot.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
13 * ====================================================
17 static char rcsid[] = "$FreeBSD$";
21 #include "math_private.h"
24 __ieee754_hypotf(float x, float y)
26 float a=x,b=y,t1,t2,y1,y2,w;
33 if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
34 SET_FLOAT_WORD(a,ha); /* a <- |a| */
35 SET_FLOAT_WORD(b,hb); /* b <- |b| */
36 if((ha-hb)>0xf000000) {return a+b;} /* x/y > 2**30 */
38 if(ha > 0x58800000) { /* a>2**50 */
39 if(ha >= 0x7f800000) { /* Inf or NaN */
40 w = a+b; /* for sNaN */
41 if(ha == 0x7f800000) w = a;
42 if(hb == 0x7f800000) w = b;
45 /* scale a and b by 2**-68 */
46 ha -= 0x22000000; hb -= 0x22000000; k += 68;
50 if(hb < 0x26800000) { /* b < 2**-50 */
51 if(hb <= 0x007fffff) { /* subnormal b or 0 */
53 SET_FLOAT_WORD(t1,0x7e800000); /* t1=2^126 */
57 } else { /* scale a and b by 2^68 */
58 ha += 0x22000000; /* a *= 2^68 */
59 hb += 0x22000000; /* b *= 2^68 */
65 /* medium size a and b */
68 SET_FLOAT_WORD(t1,ha&0xfffff000);
70 w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1)));
73 SET_FLOAT_WORD(y1,hb&0xfffff000);
75 SET_FLOAT_WORD(t1,ha+0x00800000);
77 w = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b)));
80 SET_FLOAT_WORD(t1,0x3f800000+(k<<23));