1 /* s_frexpf.c -- float version of s_frexp.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 <sys/cdefs.h>
17 __FBSDID("$FreeBSD$");
18
19 #include "math.h"
20 #include "math_private.h"
21
22 static const float
23 two25 = 3.3554432000e+07; /* 0x4c000000 */
24
25 float
frexpf(float x,int * eptr)26 frexpf(float x, int *eptr)
27 {
28 int32_t hx,ix;
29 GET_FLOAT_WORD(hx,x);
30 ix = 0x7fffffff&hx;
31 *eptr = 0;
32 if(ix>=0x7f800000||(ix==0)) return x; /* 0,inf,nan */
33 if (ix<0x00800000) { /* subnormal */
34 x *= two25;
35 GET_FLOAT_WORD(hx,x);
36 ix = hx&0x7fffffff;
37 *eptr = -25;
38 }
39 *eptr += (ix>>23)-126;
40 hx = (hx&0x807fffff)|0x3f000000;
41 SET_FLOAT_WORD(x,hx);
42 return x;
43 }
44