OpenCores
URL https://opencores.org/ocsvn/or1k/or1k/trunk

Subversion Repositories or1k

[/] [or1k/] [trunk/] [newlib/] [newlib/] [libm/] [math/] [ef_hypot.c] - Blame information for rev 39

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 39 lampret 
/* ef_hypot.c -- float version of e_hypot.c.
2 
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 
 */
4 
 
5 
/*
6 
 * ====================================================
7 
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 
 *
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
12 
 * is preserved.
13 
 * ====================================================
14 
 */
15 
 
16 
#include "fdlibm.h"
17 
 
18 
#ifdef __STDC__
19 
        float __ieee754_hypotf(float x, float y)
20 
#else
21 
        float __ieee754_hypotf(x,y)
22 
        float x, y;
23 
#endif
24 
{
25 
        float a=x,b=y,t1,t2,y1,y2,w;
26 
        __int32_t j,k,ha,hb;
27 
 
28 
        GET_FLOAT_WORD(ha,x);
29 
        ha &= 0x7fffffffL;
30 
        GET_FLOAT_WORD(hb,y);
31 
        hb &= 0x7fffffffL;
32 
        if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
33 
        SET_FLOAT_WORD(a,ha);   /* a <- |a| */
34 
        SET_FLOAT_WORD(b,hb);   /* b <- |b| */
35 
        if((ha-hb)>0xf000000L) {return a+b;} /* x/y > 2**30 */
36 
        k=0;
37 
        if(ha > 0x58800000L) {  /* a>2**50 */
38 
           if(ha >= 0x7f800000L) {      /* Inf or NaN */
39 
               w = a+b;                 /* for sNaN */
40 
               if(ha == 0x7f800000L) w = a;
41 
               if(hb == 0x7f800000L) w = b;
42 
               return w;
43 
           }
44 
           /* scale a and b by 2**-60 */
45 
           ha -= 0x5d800000L; hb -= 0x5d800000L;        k += 60;
46 
           SET_FLOAT_WORD(a,ha);
47 
           SET_FLOAT_WORD(b,hb);
48 
        }
49 
        if(hb < 0x26800000L) {  /* b < 2**-50 */
50 
            if(hb <= 0x007fffffL) {     /* subnormal b or 0 */
51 
                if(hb==0) return a;
52 
                SET_FLOAT_WORD(t1,0x3f000000L); /* t1=2^126 */
53 
                b *= t1;
54 
                a *= t1;
55 
                k -= 126;
56 
            } else {            /* scale a and b by 2^60 */
57 
                ha += 0x5d800000;       /* a *= 2^60 */
58 
                hb += 0x5d800000;       /* b *= 2^60 */
59 
                k -= 60;
60 
                SET_FLOAT_WORD(a,ha);
61 
                SET_FLOAT_WORD(b,hb);
62 
            }
63 
        }
64 
    /* medium size a and b */
65 
        w = a-b;
66 
        if (w>b) {
67 
            SET_FLOAT_WORD(t1,ha&0xfffff000L);
68 
            t2 = a-t1;
69 
            w  = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1)));
70 
        } else {
71 
            a  = a+a;
72 
            SET_FLOAT_WORD(y1,hb&0xfffff000L);
73 
            y2 = b - y1;
74 
            SET_FLOAT_WORD(t1,ha+0x00800000L);
75 
            t2 = a - t1;
76 
            w  = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b)));
77 
        }
78 
        if(k!=0) {
79 
            SET_FLOAT_WORD(t1,0x3f800000L+(k<<23));
80 
            return t1*w;
81 
        } else return w;
82 
}

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.