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+#ifndef MY_ATOMIC_INCLUDED
+#define MY_ATOMIC_INCLUDED
+
+/* Copyright (c) 2006, 2016, Oracle and/or its affiliates. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
+
+/*
+ This header defines five atomic operations:
+
+ my_atomic_add#(&var, what)
+ 'Fetch and Add'
+ add 'what' to *var, and return the old value of *var
+
+ my_atomic_fas#(&var, what)
+ 'Fetch And Store'
+ store 'what' in *var, and return the old value of *var
+
+ my_atomic_cas#(&var, &old, new)
+ An odd variation of 'Compare And Set/Swap'
+ if *var is equal to *old, then store 'new' in *var, and return TRUE
+ otherwise store *var in *old, and return FALSE
+ Usually, &old should not be accessed if the operation is successful.
+
+ my_atomic_load#(&var)
+ return *var
+
+ my_atomic_store#(&var, what)
+ store 'what' in *var
+
+ '#' is substituted by a size suffix - 32, 64, or ptr
+ (e.g. my_atomic_add64, my_atomic_fas32, my_atomic_casptr).
+*/
+
+/*
+ We choose implementation as follows:
+ ------------------------------------
+ On Windows using Visual C++ the native implementation should be
+ preferrable. When using gcc we prefer the Solaris implementation
+ before the gcc because of stability preference, we choose gcc
+ builtins if available. If neither Visual C++ or gcc we still choose
+ the Solaris implementation on Solaris (mainly for SunStudio compilers).
+*/
+#if defined(_MSC_VER)
+# include "atomic/generic-msvc.h"
+#elif defined(HAVE_SOLARIS_ATOMIC)
+# include "atomic/solaris.h"
+#elif defined(HAVE_GCC_SYNC_BUILTINS) /* Use old __sync by default */
+# include "atomic/gcc_sync.h"
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS) /* Use __atomic on e.g. powerpc */
+# include "atomic/gcc_atomic.h"
+#else
+# error Native atomics support not found!
+#endif
+
+/*
+ the macro below defines (as an expression) the code that
+ will be run in spin-loops. Intel manuals recummend to have PAUSE there.
+ It is expected to be defined in include/atomic/ *.h files
+*/
+#ifndef LF_BACKOFF
+#define LF_BACKOFF (1)
+#endif
+
+#endif /* MY_ATOMIC_INCLUDED */