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/*-
 *   BSD LICENSE
 * 
 *   Copyright(c) 2010-2012 Intel Corporation. All rights reserved.
 *   All rights reserved.
 * 
 *   Redistribution and use in source and binary forms, with or without 
 *   modification, are permitted provided that the following conditions 
 *   are met:
 * 
 *     * Redistributions of source code must retain the above copyright 
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright 
 *       notice, this list of conditions and the following disclaimer in 
 *       the documentation and/or other materials provided with the 
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its 
 *       contributors may be used to endorse or promote products derived 
 *       from this software without specific prior written permission.
 * 
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */

/**
 * @file
 * Branch Prediction Helpers in RTE
 */

#ifndef _RTE_BRANCH_PREDICTION_H_
#define _RTE_BRANCH_PREDICTION_H_

/**
 * Check if a branch is likely to be taken.
 *
 * This compiler builtin allows the developer to indicate if a branch is
 * likely to be taken. Example:
 *
 *   if (likely(x > 1))
 *      do_stuff();
 *
 */
#ifndef likely
#define likely(x)  __builtin_expect((x),1)
#endif /* likely */

/**
 * Check if a branch is unlikely to be taken.
 *
 * This compiler builtin allows the developer to indicate if a branch is
 * unlikely to be taken. Example:
 *
 *   if (unlikely(x < 1))
 *      do_stuff();
 *
 */
#ifndef unlikely
#define unlikely(x)  __builtin_expect((x),0)
#endif /* unlikely */

#endif /* _RTE_BRANCH_PREDICTION_H_ */