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+/* Control when floating-point expressions are evaluated.  Generic version.
+   Copyright (C) 2007-2018 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
+   <http://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 */