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diff --git a/include/llvm/ExecutionEngine/Orc/ExecutionUtils.h b/include/llvm/ExecutionEngine/Orc/ExecutionUtils.h
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+//===-- ExecutionUtils.h - Utilities for executing code in Orc --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Contains utilities for executing code in Orc.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H
+#define LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H
+
+#include "JITSymbol.h"
+#include "llvm/ADT/iterator_range.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ExecutionEngine/RuntimeDyld.h"
+#include <vector>
+
+namespace llvm {
+
+class ConstantArray;
+class GlobalVariable;
+class Function;
+class Module;
+class Value;
+
+namespace orc {
+
+/// @brief This iterator provides a convenient way to iterate over the elements
+///        of an llvm.global_ctors/llvm.global_dtors instance.
+///
+///   The easiest way to get hold of instances of this class is to use the
+/// getConstructors/getDestructors functions.
+class CtorDtorIterator {
+public:
+
+  /// @brief Accessor for an element of the global_ctors/global_dtors array.
+  ///
+  ///   This class provides a read-only view of the element with any casts on
+  /// the function stripped away.
+  struct Element {
+    Element(unsigned Priority, const Function *Func, const Value *Data)
+      : Priority(Priority), Func(Func), Data(Data) {}
+
+    unsigned Priority;
+    const Function *Func;
+    const Value *Data;
+  };
+
+  /// @brief Construct an iterator instance. If End is true then this iterator
+  ///        acts as the end of the range, otherwise it is the beginning.
+  CtorDtorIterator(const GlobalVariable *GV, bool End);
+
+  /// @brief Test iterators for equality.
+  bool operator==(const CtorDtorIterator &Other) const;
+
+  /// @brief Test iterators for inequality.
+  bool operator!=(const CtorDtorIterator &Other) const;
+
+  /// @brief Pre-increment iterator.
+  CtorDtorIterator& operator++();
+
+  /// @brief Post-increment iterator.
+  CtorDtorIterator operator++(int);
+
+  /// @brief Dereference iterator. The resulting value provides a read-only view
+  ///        of this element of the global_ctors/global_dtors list.
+  Element operator*() const;
+
+private:
+  const ConstantArray *InitList;
+  unsigned I;
+};
+
+/// @brief Create an iterator range over the entries of the llvm.global_ctors
+///        array.
+iterator_range<CtorDtorIterator> getConstructors(const Module &M);
+
+/// @brief Create an iterator range over the entries of the llvm.global_ctors
+///        array.
+iterator_range<CtorDtorIterator> getDestructors(const Module &M);
+
+/// @brief Convenience class for recording constructor/destructor names for
+///        later execution.
+template <typename JITLayerT>
+class CtorDtorRunner {
+public:
+
+  /// @brief Construct a CtorDtorRunner for the given range using the given
+  ///        name mangling function.
+  CtorDtorRunner(std::vector<std::string> CtorDtorNames,
+                 typename JITLayerT::ModuleSetHandleT H)
+      : CtorDtorNames(std::move(CtorDtorNames)), H(H) {}
+
+  /// @brief Run the recorded constructors/destructors through the given JIT
+  ///        layer.
+  bool runViaLayer(JITLayerT &JITLayer) const {
+    typedef void (*CtorDtorTy)();
+
+    bool Error = false;
+    for (const auto &CtorDtorName : CtorDtorNames)
+      if (auto CtorDtorSym = JITLayer.findSymbolIn(H, CtorDtorName, false)) {
+        CtorDtorTy CtorDtor =
+          reinterpret_cast<CtorDtorTy>(
+            static_cast<uintptr_t>(CtorDtorSym.getAddress()));
+        CtorDtor();
+      } else
+        Error = true;
+    return !Error;
+  }
+
+private:
+  std::vector<std::string> CtorDtorNames;
+  typename JITLayerT::ModuleSetHandleT H;
+};
+
+/// @brief Support class for static dtor execution. For hosted (in-process) JITs
+///        only!
+///
+///   If a __cxa_atexit function isn't found C++ programs that use static
+/// destructors will fail to link. However, we don't want to use the host
+/// process's __cxa_atexit, because it will schedule JIT'd destructors to run
+/// after the JIT has been torn down, which is no good. This class makes it easy
+/// to override __cxa_atexit (and the related __dso_handle).
+///
+///   To use, clients should manually call searchOverrides from their symbol
+/// resolver. This should generally be done after attempting symbol resolution
+/// inside the JIT, but before searching the host process's symbol table. When
+/// the client determines that destructors should be run (generally at JIT
+/// teardown or after a return from main), the runDestructors method should be
+/// called.
+class LocalCXXRuntimeOverrides {
+public:
+
+  /// Create a runtime-overrides class.
+  template <typename MangleFtorT>
+  LocalCXXRuntimeOverrides(const MangleFtorT &Mangle) {
+    addOverride(Mangle("__dso_handle"), toTargetAddress(&DSOHandleOverride));
+    addOverride(Mangle("__cxa_atexit"), toTargetAddress(&CXAAtExitOverride));
+  }
+
+  /// Search overrided symbols.
+  RuntimeDyld::SymbolInfo searchOverrides(const std::string &Name) {
+    auto I = CXXRuntimeOverrides.find(Name);
+    if (I != CXXRuntimeOverrides.end())
+      return RuntimeDyld::SymbolInfo(I->second, JITSymbolFlags::Exported);
+    return nullptr;
+  }
+
+  /// Run any destructors recorded by the overriden __cxa_atexit function
+  /// (CXAAtExitOverride).
+  void runDestructors();
+
+private:
+
+  template <typename PtrTy>
+  TargetAddress toTargetAddress(PtrTy* P) {
+    return static_cast<TargetAddress>(reinterpret_cast<uintptr_t>(P));
+  }
+
+  void addOverride(const std::string &Name, TargetAddress Addr) {
+    CXXRuntimeOverrides.insert(std::make_pair(Name, Addr));
+  }
+
+  StringMap<TargetAddress> CXXRuntimeOverrides;
+
+  typedef void (*DestructorPtr)(void*);
+  typedef std::pair<DestructorPtr, void*> CXXDestructorDataPair;
+  typedef std::vector<CXXDestructorDataPair> CXXDestructorDataPairList;
+  CXXDestructorDataPairList DSOHandleOverride;
+  static int CXAAtExitOverride(DestructorPtr Destructor, void *Arg,
+                               void *DSOHandle);
+};
+
+} // End namespace orc.
+} // End namespace llvm.
+
+#endif // LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H