glibc/math/w_llogb_template.c

48 lines
1.4 KiB
C

/* Wrapper to implement llogb in terms of ilogb.
Copyright (C) 2012-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <math.h>
#include <errno.h>
#include <limits.h>
#include <math_private.h>
#include <fenv.h>
long int
M_DECL_FUNC (__llogb) (FLOAT x)
{
int r = M_SUF (__ieee754_ilogb) (x);
long int lr = r;
if (__glibc_unlikely (r == FP_ILOGB0)
|| __glibc_unlikely (r == FP_ILOGBNAN)
|| __glibc_unlikely (r == INT_MAX))
{
#if LONG_MAX != INT_MAX
if (r == FP_ILOGB0)
lr = FP_LLOGB0;
else if (r == FP_ILOGBNAN)
lr = FP_LLOGBNAN;
else
lr = LONG_MAX;
#endif
__set_errno (EDOM);
__feraiseexcept (FE_INVALID);
}
return lr;
}
declare_mgen_alias (__llogb, llogb)