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/*
* Copyright (c) 2016-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
* LICENSE file in the root directory of this source tree) and the GPLv2 (found
* in the COPYING file in the root directory of this source tree).
*/
/**
* Compiler hints to indicate the fast path of an "if" branch: whether
* the if condition is likely to be true or false.
*
* @author Tudor Bosman (tudorb@fb.com)
*/
#pragma once
#undef LIKELY
#undef UNLIKELY
#if defined(__GNUC__) && __GNUC__ >= 4
#define LIKELY(x) (__builtin_expect((x), 1))
#define UNLIKELY(x) (__builtin_expect((x), 0))
#else
#define LIKELY(x) (x)
#define UNLIKELY(x) (x)
#endif
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