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/* Narrow floating-point values to their semantic type.
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   Copyright (C) 2015-2018 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library; if not, see
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   <http://www.gnu.org/licenses/>.  */
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#ifndef _MATH_NARROW_EVAL_H
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#define _MATH_NARROW_EVAL_H	1
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#include <float.h>
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/* math_narrow_eval reduces its floating-point argument to the range
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   and precision of its semantic type.  (The original evaluation may
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   still occur with excess range and precision, so the result may be
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   affected by double rounding.)  */
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#if FLT_EVAL_METHOD == 0
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# define math_narrow_eval(x) (x)
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#else
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# if FLT_EVAL_METHOD == 1
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#  define excess_precision(type) __builtin_types_compatible_p (type, float)
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# else
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#  define excess_precision(type) (__builtin_types_compatible_p (type, float) \
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				  || __builtin_types_compatible_p (type, \
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								   double))
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# endif
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# define math_narrow_eval(x)					\
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  ({								\
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    __typeof (x) math_narrow_eval_tmp = (x);			\
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    if (excess_precision (__typeof (math_narrow_eval_tmp)))	\
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      __asm__ ("" : "+m" (math_narrow_eval_tmp));		\
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    math_narrow_eval_tmp;					\
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   })
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#endif
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#endif /* math-narrow-eval.h */