s_frexpf.c revision 97409 
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#ifndef lint
17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_frexpf.c 97409 2002-05-28 17:51:46Z alfred $";
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23static const float
24two25 =  3.3554432000e+07; /* 0x4c000000 */
25
26	float 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	*(int*)&x = hx;
42	return x;
43}
44