1 /* e_hypotf.c -- float version of e_hypot.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
4 * $FreeBSD: src/lib/msun/src/e_hypotf.c,v 1.7 1999/08/28 00:06:32 peter Exp $
5 * $DragonFly: src/lib/msun/src/Attic/e_hypotf.c,v 1.2 2003/06/17 04:26:52 dillon Exp $
9 * ====================================================
10 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
12 * Developed at SunPro, a Sun Microsystems, Inc. business.
13 * Permission to use, copy, modify, and distribute this
14 * software is freely granted, provided that this notice
16 * ====================================================
20 #include "math_private.h"
23 float __ieee754_hypotf(float x, float y)
25 float __ieee754_hypot(x,y)
29 float a=x,b=y,t1,t2,y1,y2,w;
36 if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
37 SET_FLOAT_WORD(a,ha); /* a <- |a| */
38 SET_FLOAT_WORD(b,hb); /* b <- |b| */
39 if((ha-hb)>0xf000000) {return a+b;} /* x/y > 2**30 */
41 if(ha > 0x58800000) { /* a>2**50 */
42 if(ha >= 0x7f800000) { /* Inf or NaN */
43 w = a+b; /* for sNaN */
44 if(ha == 0x7f800000) w = a;
45 if(hb == 0x7f800000) w = b;
48 /* scale a and b by 2**-68 */
49 ha -= 0x22000000; hb -= 0x22000000; k += 68;
53 if(hb < 0x26800000) { /* b < 2**-50 */
54 if(hb <= 0x007fffff) { /* subnormal b or 0 */
56 SET_FLOAT_WORD(t1,0x7e800000); /* t1=2^126 */
60 } else { /* scale a and b by 2^68 */
61 ha += 0x22000000; /* a *= 2^68 */
62 hb += 0x22000000; /* b *= 2^68 */
68 /* medium size a and b */
71 SET_FLOAT_WORD(t1,ha&0xfffff000);
73 w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1)));
76 SET_FLOAT_WORD(y1,hb&0xfffff000);
78 SET_FLOAT_WORD(t1,ha+0x00800000);
80 w = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b)));
83 SET_FLOAT_WORD(t1,0x3f800000+(k<<23));