diff --git a/src/instrumentation.h b/src/instrumentation.h
new file mode 100644
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--- /dev/null
+++ b/src/instrumentation.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_SRC_INSTRUMENTATION_H_
+#define ART_SRC_INSTRUMENTATION_H_
+
+#include <ostream>
+#include <set>
+#include <string>
+
+#include "file.h"
+#include "globals.h"
+#include "macros.h"
+#include "safe_map.h"
+#include "trace.h"
+#include "UniquePtr.h"
+
+namespace art {
+
+class AbstractMethod;
+class Thread;
+
+uint32_t InstrumentationMethodUnwindFromCode(Thread* self);
+
+struct InstrumentationStackFrame {
+  InstrumentationStackFrame(AbstractMethod* method, uintptr_t return_pc)
+      : method_(method), return_pc_(return_pc) {
+  }
+
+  AbstractMethod* method_;
+  uintptr_t return_pc_;
+};
+
+class Instrumentation {
+ public:
+  Instrumentation() {}
+  ~Instrumentation();
+
+  // Replaces code of each method with a pointer to a stub for method tracing.
+  void InstallStubs();
+
+  // Restores original code for each method and fixes the return values of each thread's stack.
+  void UninstallStubs() LOCKS_EXCLUDED(Locks::thread_list_lock_);
+
+  const void* GetSavedCodeFromMap(const AbstractMethod* method);
+  void SaveAndUpdateCode(AbstractMethod* method);
+  void ResetSavedCode(AbstractMethod* method);
+
+  Trace* GetTrace() const;
+  void SetTrace(Trace* trace);
+  void RemoveTrace();
+
+ private:
+  void AddSavedCodeToMap(const AbstractMethod* method, const void* code);
+  void RemoveSavedCodeFromMap(const AbstractMethod* method);
+
+  // Maps a method to its original code pointer.
+  SafeMap<const AbstractMethod*, const void*> saved_code_map_;
+
+  Trace* trace_;
+
+  DISALLOW_COPY_AND_ASSIGN(Instrumentation);
+};
+
+}  // namespace art
+
+#endif  // ART_SRC_INSTRUMENTATION_H_