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diff --git a/tools/lli/OrcLazyJIT.h b/tools/lli/OrcLazyJIT.h
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+//===--- OrcLazyJIT.h - Basic Orc-based JIT for lazy execution --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Simple Orc-based JIT. Uses the compile-on-demand layer to break up and
+// lazily compile modules.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TOOLS_LLI_ORCLAZYJIT_H
+#define LLVM_TOOLS_LLI_ORCLAZYJIT_H
+
+#include "llvm/ADT/Triple.h"
+#include "llvm/ExecutionEngine/Orc/CompileOnDemandLayer.h"
+#include "llvm/ExecutionEngine/Orc/CompileUtils.h"
+#include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
+#include "llvm/ExecutionEngine/Orc/IRCompileLayer.h"
+#include "llvm/ExecutionEngine/Orc/IRTransformLayer.h"
+#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
+#include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
+#include "llvm/IR/LLVMContext.h"
+
+namespace llvm {
+
+class OrcLazyJIT {
+public:
+
+  typedef orc::JITCompileCallbackManagerBase CompileCallbackMgr;
+  typedef orc::ObjectLinkingLayer<> ObjLayerT;
+  typedef orc::IRCompileLayer<ObjLayerT> CompileLayerT;
+  typedef std::function<std::unique_ptr<Module>(std::unique_ptr<Module>)>
+    TransformFtor;
+  typedef orc::IRTransformLayer<CompileLayerT, TransformFtor> IRDumpLayerT;
+  typedef orc::CompileOnDemandLayer<IRDumpLayerT, CompileCallbackMgr> CODLayerT;
+  typedef CODLayerT::ModuleSetHandleT ModuleHandleT;
+
+  typedef std::function<
+            std::unique_ptr<CompileCallbackMgr>(IRDumpLayerT&,
+                                                RuntimeDyld::MemoryManager&,
+                                                LLVMContext&)>
+    CallbackManagerBuilder;
+
+  static CallbackManagerBuilder createCallbackManagerBuilder(Triple T);
+
+  OrcLazyJIT(std::unique_ptr<TargetMachine> TM, LLVMContext &Context,
+             CallbackManagerBuilder &BuildCallbackMgr)
+    : TM(std::move(TM)),
+      Mang(this->TM->getDataLayout()),
+      ObjectLayer(),
+      CompileLayer(ObjectLayer, orc::SimpleCompiler(*this->TM)),
+      IRDumpLayer(CompileLayer, createDebugDumper()),
+      CCMgr(BuildCallbackMgr(IRDumpLayer, CCMgrMemMgr, Context)),
+      CODLayer(IRDumpLayer, *CCMgr),
+      CXXRuntimeOverrides([this](const std::string &S) { return mangle(S); }) {}
+
+  ~OrcLazyJIT() {
+    // Run any destructors registered with __cxa_atexit.
+    CXXRuntimeOverrides.runDestructors();
+    // Run any IR destructors.
+    for (auto &DtorRunner : IRStaticDestructorRunners)
+      DtorRunner.runViaLayer(CODLayer);
+  }
+
+  template <typename PtrTy>
+  static PtrTy fromTargetAddress(orc::TargetAddress Addr) {
+    return reinterpret_cast<PtrTy>(static_cast<uintptr_t>(Addr));
+  }
+
+  ModuleHandleT addModule(std::unique_ptr<Module> M) {
+    // Attach a data-layout if one isn't already present.
+    if (M->getDataLayout().isDefault())
+      M->setDataLayout(*TM->getDataLayout());
+
+    // Record the static constructors and destructors. We have to do this before
+    // we hand over ownership of the module to the JIT.
+    std::vector<std::string> CtorNames, DtorNames;
+    for (auto Ctor : orc::getConstructors(*M))
+      CtorNames.push_back(mangle(Ctor.Func->getName()));
+    for (auto Dtor : orc::getDestructors(*M))
+      DtorNames.push_back(mangle(Dtor.Func->getName()));
+
+    // Symbol resolution order:
+    //   1) Search the JIT symbols.
+    //   2) Check for C++ runtime overrides.
+    //   3) Search the host process (LLI)'s symbol table.
+    auto Resolver =
+      orc::createLambdaResolver(
+        [this](const std::string &Name) {
+
+          if (auto Sym = CODLayer.findSymbol(Name, true))
+            return RuntimeDyld::SymbolInfo(Sym.getAddress(), Sym.getFlags());
+
+          if (auto Sym = CXXRuntimeOverrides.searchOverrides(Name))
+            return Sym;
+
+          if (auto Addr = RTDyldMemoryManager::getSymbolAddressInProcess(Name))
+            return RuntimeDyld::SymbolInfo(Addr, JITSymbolFlags::Exported);
+
+          return RuntimeDyld::SymbolInfo(nullptr);
+        },
+        [](const std::string &Name) { return RuntimeDyld::SymbolInfo(nullptr); }
+      );
+
+    // Add the module to the JIT.
+    std::vector<std::unique_ptr<Module>> S;
+    S.push_back(std::move(M));
+    auto H = CODLayer.addModuleSet(std::move(S), nullptr, std::move(Resolver));
+
+    // Run the static constructors, and save the static destructor runner for
+    // execution when the JIT is torn down.
+    orc::CtorDtorRunner<CODLayerT> CtorRunner(std::move(CtorNames), H);
+    CtorRunner.runViaLayer(CODLayer);
+
+    IRStaticDestructorRunners.push_back(
+        orc::CtorDtorRunner<CODLayerT>(std::move(DtorNames), H));
+
+    return H;
+  }
+
+  orc::JITSymbol findSymbol(const std::string &Name) {
+    return CODLayer.findSymbol(mangle(Name), true);
+  }
+
+  orc::JITSymbol findSymbolIn(ModuleHandleT H, const std::string &Name) {
+    return CODLayer.findSymbolIn(H, mangle(Name), true);
+  }
+
+private:
+
+  std::string mangle(const std::string &Name) {
+    std::string MangledName;
+    {
+      raw_string_ostream MangledNameStream(MangledName);
+      Mang.getNameWithPrefix(MangledNameStream, Name);
+    }
+    return MangledName;
+  }
+
+  static TransformFtor createDebugDumper();
+
+  std::unique_ptr<TargetMachine> TM;
+  Mangler Mang;
+  SectionMemoryManager CCMgrMemMgr;
+
+  ObjLayerT ObjectLayer;
+  CompileLayerT CompileLayer;
+  IRDumpLayerT IRDumpLayer;
+  std::unique_ptr<CompileCallbackMgr> CCMgr;
+  CODLayerT CODLayer;
+
+  orc::LocalCXXRuntimeOverrides CXXRuntimeOverrides;
+  std::vector<orc::CtorDtorRunner<CODLayerT>> IRStaticDestructorRunners;
+};
+
+int runOrcLazyJIT(std::unique_ptr<Module> M, int ArgC, char* ArgV[]);
+
+} // end namespace llvm
+
+#endif