1
/* @(#)s_logb.c 5.1 93/09/24 */
3
* ====================================================
4
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6
* Developed at SunPro, a Sun Microsystems, Inc. business.
7
* Permission to use, copy, modify, and distribute this
8
* software is freely granted, provided that this notice
10
* ====================================================
15
* IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
20
#include <math_private.h>
27
EXTRACT_WORDS (ix, lx, x);
28
ix &= 0x7fffffff; /* high |x| */
30
return -1.0 / fabs (x);
33
if (__builtin_expect ((rix = ix >> 20) == 0, 0))
35
/* POSIX specifies that denormal number is treated as
36
though it were normalized. */
39
ma = __builtin_clz (lx) + 32;
41
ma = __builtin_clz (ix);
44
return (double) (rix - 1023);
46
weak_alias (__logb, logb)
48
strong_alias (__logb, __logbl) weak_alias (__logb, logbl)