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+/*
+ * Copyright (c) 2013 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * 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 the copyright holders 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.
+ *
+ * Authors: Ali Saidi
+ */
+
+#ifndef __BASE_BARRIER_HH__
+#define __BASE_BARRIER_HH__
+
+#include <condition_variable>
+
+class Barrier
+{
+  private:
+    /// Mutex to protect access to numLeft and generation
+    std::mutex bMutex;
+    /// Condition variable for waiting on barrier
+    std::condition_variable bCond;
+    /// Number of threads we should be waiting for before completing the barrier
+    unsigned numWaiting;
+    /// Generation of this barrier
+    unsigned generation;
+    /// Number of threads remaining for the current generation
+    unsigned numLeft;
+
+  public:
+    Barrier(unsigned _numWaiting)
+        : numWaiting(_numWaiting), generation(0), numLeft(_numWaiting)
+    {}
+
+    bool
+    wait()
+    {
+        std::unique_lock<std::mutex> lock(bMutex);
+        unsigned int gen = generation;
+
+        if (--numLeft == 0) {
+            generation++;
+            numLeft = numWaiting;
+            bCond.notify_all();
+            return true;
+        }
+        while (gen == generation)
+            bCond.wait(lock);
+        return false;
+    }
+};
+
+#endif // __BASE_BARRIER_HH__