1/* Wrapper to implement llogb in terms of ilogb.
2 Copyright (C) 2012-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <math.h>
20#include <errno.h>
21#include <limits.h>
22#include <math_private.h>
23#include <fenv.h>
24
25long int
26M_DECL_FUNC (__llogb) (FLOAT x)
27{
28 int r = M_SUF (__ieee754_ilogb) (x);
29 long int lr = r;
30 if (__glibc_unlikely (r == FP_ILOGB0)
31 || __glibc_unlikely (r == FP_ILOGBNAN)
32 || __glibc_unlikely (r == INT_MAX))
33 {
34#if LONG_MAX != INT_MAX
35 if (r == FP_ILOGB0)
36 lr = FP_LLOGB0;
37 else if (r == FP_ILOGBNAN)
38 lr = FP_LLOGBNAN;
39 else
40 lr = LONG_MAX;
41#endif
42 __set_errno (EDOM);
43 __feraiseexcept (FE_INVALID);
44 }
45 return lr;
46}
47declare_mgen_alias (__llogb, llogb)
48

source code of glibc/math/w_llogb_template.c