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diff --git a/Source/JavaScriptCore/ftl/FTLWeightedTarget.h b/Source/JavaScriptCore/ftl/FTLWeightedTarget.h
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+++ b/Source/JavaScriptCore/ftl/FTLWeightedTarget.h
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+/*
+ * Copyright (C) 2014, 2016 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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. 
+ */
+
+#pragma once
+
+#if ENABLE(FTL_JIT)
+
+#include "FTLAbbreviatedTypes.h"
+#include "FTLWeight.h"
+
+namespace JSC { namespace FTL {
+
+class WeightedTarget {
+public:
+    WeightedTarget()
+        : m_target(nullptr)
+    {
+    }
+    
+    WeightedTarget(LBasicBlock target, Weight weight)
+        : m_target(target)
+        , m_weight(weight)
+    {
+    }
+    
+    WeightedTarget(LBasicBlock target, float weight)
+        : m_target(target)
+        , m_weight(weight)
+    {
+    }
+    
+    LBasicBlock target() const { return m_target; }
+    Weight weight() const { return m_weight; }
+    
+    B3::FrequentedBlock frequentedBlock() const
+    {
+        return B3::FrequentedBlock(target(), weight().frequencyClass());
+    }
+    
+private:
+    LBasicBlock m_target;
+    Weight m_weight;
+};
+
+// Helpers for creating weighted targets for statically known (or unknown) branch
+// profiles.
+
+inline WeightedTarget usually(LBasicBlock block)
+{
+    return WeightedTarget(block, 1);
+}
+
+inline WeightedTarget rarely(LBasicBlock block)
+{
+    return WeightedTarget(block, 0);
+}
+
+// Currently in B3 this is the equivalent of "usually", but we like to make the distinction in
+// case we ever make B3 support proper branch weights. We used to do that in LLVM.
+inline WeightedTarget unsure(LBasicBlock block)
+{
+    return WeightedTarget(block, Weight());
+}
+
+} } // namespace JSC::FTL
+
+#endif // ENABLE(FTL_JIT)