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diff --git a/Source/JavaScriptCore/b3/air/AirPadInterference.cpp b/Source/JavaScriptCore/b3/air/AirPadInterference.cpp
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+++ b/Source/JavaScriptCore/b3/air/AirPadInterference.cpp
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+/*
+ * Copyright (C) 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. 
+ */
+
+#include "config.h"
+#include "AirPadInterference.h"
+
+#if ENABLE(B3_JIT)
+
+#include "AirCode.h"
+#include "AirInsertionSet.h"
+#include "AirInstInlines.h"
+
+namespace JSC { namespace B3 { namespace Air {
+
+void padInterference(Code& code)
+{
+    InsertionSet insertionSet(code);
+    for (BasicBlock* block : code) {
+        bool prevHadLate = false;
+        for (unsigned instIndex = 0; instIndex < block->size(); ++instIndex) {
+            Inst& inst = block->at(instIndex);
+            
+            bool hasEarlyDef = false;
+            bool hasLate = false;
+            inst.forEachArg(
+                [&] (Arg&, Arg::Role role, Arg::Type, Arg::Width) {
+                    switch (role) {
+                    case Arg::EarlyDef:
+                        hasEarlyDef = true;
+                        break;
+                    case Arg::LateUse:
+                    case Arg::Def:
+                    case Arg::ZDef:
+                    case Arg::LateColdUse:
+                    case Arg::UseDef:
+                    case Arg::UseZDef:
+                        hasLate = true;
+                        break;
+                    case Arg::Scratch:
+                        hasEarlyDef = true;
+                        hasLate = true;
+                        break;
+                    case Arg::Use:
+                    case Arg::ColdUse:
+                    case Arg::UseAddr:
+                        break;
+                    }
+                });
+            if (inst.kind.opcode == Patch) {
+                hasEarlyDef |= !inst.extraEarlyClobberedRegs().isEmpty();
+                hasLate |= !inst.extraClobberedRegs().isEmpty();
+            }
+            
+            if (hasEarlyDef && prevHadLate)
+                insertionSet.insert(instIndex, Nop, inst.origin);
+            
+            prevHadLate = hasLate;
+        }
+        insertionSet.execute(block);
+    }
+}
+
+} } } // namespace JSC::B3::Air
+
+#endif // ENABLE(B3_JIT)
+