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