1 /* s_logbl.c -- long double version of s_logb.c.
2 * Conversion to long double by Ulrich Drepper,
3 * Cygnus Support, drepper@cygnus.com.
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
14 * ====================================================
18 * long double logbl(x)
19 * IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
24 #include <math_private.h>
27 __logbl (long double x
)
31 GET_LDOUBLE_WORDS (es
, ix
, lx
, x
);
32 es
&= 0x7fff; /* exponent */
33 if ((es
| ix
| lx
) == 0)
34 return -1.0 / fabsl (x
);
37 if (es
== 0) /* IEEE 754 logb */
39 /* POSIX specifies that denormal number is treated as
40 though it were normalized. */
42 es
= -(__builtin_clz (lx
) + 32);
44 es
= -__builtin_clz (ix
);
46 return (long double) (es
- 16383);
49 weak_alias (__logbl
, logbl
)