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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.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+/**
+ * @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_ */