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/* Compute x * y + z as ternary operation.
Copyright (C) 2011-2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Flaherty <flaherty@linux.vnet.ibm.com>.
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_ldbl_opt.h>
long double
__fmal (long double x, long double y, long double z)
{
/* An IBM long double 128 is really just 2 IEEE64 doubles, and in
* the case of inf/nan only the first double counts. So we use the
* (double) cast to avoid any data movement. */
if ((finite ((double)x) && finite ((double)y)) && isinf ((double)z))
return (z);
/* If z is zero and x are y are nonzero, compute the result
as x * y to avoid the wrong sign of a zero result if x * y
underflows to 0. */
if (z == 0 && x != 0 && y != 0)
return x * y;
return (x * y) + z;
}
#ifdef IS_IN_libm
long_double_symbol (libm, __fmal, fmal);
#else
long_double_symbol (libc, __fmal, fmal);
#endif
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