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/* Control when floating-point expressions are evaluated. Generic version.
Copyright (C) 2007-2020 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/>. */
#ifndef _MATH_BARRIERS_H
#define _MATH_BARRIERS_H 1
/* math_opt_barrier evaluates and returns its floating-point argument
and ensures that the evaluation of any expression using the result
of math_opt_barrier is not moved before the call. math_force_eval
ensures that its floating-point argument is evaluated for its side
effects even if its value is apparently unused, and that the
evaluation of its argument is not moved after the call. Both these
macros are used to ensure the correct ordering of floating-point
expression evaluations with respect to accesses to the
floating-point environment. */
#define math_opt_barrier(x) \
({ __typeof (x) __x = (x); __asm ("" : "+m" (__x)); __x; })
#define math_force_eval(x) \
({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "m" (__x)); })
#endif /* math-barriers.h */
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