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/* Copyright (C) 2011-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
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
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include "math_private.h"
#if __UCLIBC_HAS_FENV__
#include <errno.h>
static double
__attribute__ ((noinline))
sysv_scalb (double x, double fn)
{
double z = __ieee754_scalb (x, fn);
if (__builtin_expect (isinf (z), 0))
{
if (isfinite (x))
return __kernel_standard (x, fn, 32); /* scalb overflow */
else
__set_errno (ERANGE);
}
else if (__builtin_expect (z == 0.0, 0) && z != x)
return __kernel_standard (x, fn, 33); /* scalb underflow */
return z;
}
#endif /* __UCLIBC_HAS_FENV__ */
/* Here might be a check like "#if defined __UCLIBC_SUSV3_LEGACY__"
* but because there is a sysv_scalb() func, it was decided
* not to check yhis macro.
*/
/* Wrapper scalb */
double
scalb (double x, double fn)
{
#if __UCLIBC_HAS_FENV__
if (__builtin_expect (_LIB_VERSION == _SVID_,0))
return sysv_scalb (x, fn);
else
{
double z = __ieee754_scalb (x, fn);
if (__builtin_expect (!isfinite (z) || z == 0.0, 0))
{
if (isnan (z))
{
if (!isnan (x) && !isnan (fn))
__set_errno (EDOM);
}
else if (isinf (z))
{
if (!isinf (x) && !isinf (fn))
__set_errno (ERANGE);
}
else
{
/* z == 0. */
if (x != 0.0 && !isinf (fn))
__set_errno (ERANGE);
}
}
return z;
}
#else
return __ieee754_scalb (x, fn);
#endif /* __UCLIBC_HAS_FENV__ */
}
libm_hidden_def(scalb)
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