blob: 5f2816382d56b587eaef815adc9361e57f210691 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
/* s_ilogbf.c -- float version of s_ilogb.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "math.h"
#include "math_private.h"
int
ilogbf(float x)
{
int32_t hx,ix;
GET_FLOAT_WORD(hx,x);
hx &= 0x7fffffff;
if(hx<0x00800000) {
if(hx==0)
return FP_ILOGB0; /* ilogb(0) = FP_ILOGB */
else /* subnormal x */
for (ix = -126,hx<<=8; hx>0; hx<<=1) ix -=1;
return ix;
}
else if (hx<0x7f800000) return (hx>>23)-127;
else if (hx>0x7f800000) return FP_ILOGBNAN;
else return INT_MAX;
}
DEF_STD(ilogbf);
|
