1 /* s_ilogbf.c -- float version of s_ilogb.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 <limits.h>
17
18 #include "math.h"
19 #include "math_private.h"
20
21 int
ilogbf(float x)22 ilogbf(float x)
23 {
24 int32_t hx,ix;
25
26 GET_FLOAT_WORD(hx,x);
27 hx &= 0x7fffffff;
28 if(hx<0x00800000) {
29 if(hx==0)
30 return FP_ILOGB0;
31 else /* subnormal x */
32 ix = subnormal_ilogbf(hx);
33 return ix;
34 }
35 else if (hx<0x7f800000) return (hx>>23)-127;
36 else if (hx>0x7f800000) return FP_ILOGBNAN;
37 else return INT_MAX;
38 }
39