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diff --git a/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp b/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp
new file mode 100644
index 0000000..7b85f65
--- /dev/null
+++ b/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp
@@ -0,0 +1,382 @@
+//===------- ObjectLinkingLayer.cpp - JITLink backed ORC ObjectLayer ------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
+
+#include "llvm/ADT/Optional.h"
+#include "llvm/ExecutionEngine/JITLink/JITLink_EHFrameSupport.h"
+
+#include <vector>
+
+#define DEBUG_TYPE "orc"
+
+using namespace llvm;
+using namespace llvm::jitlink;
+using namespace llvm::orc;
+
+namespace llvm {
+namespace orc {
+
+class ObjectLinkingLayerJITLinkContext final : public JITLinkContext {
+public:
+  ObjectLinkingLayerJITLinkContext(ObjectLinkingLayer &Layer,
+                                   MaterializationResponsibility MR,
+                                   std::unique_ptr<MemoryBuffer> ObjBuffer)
+      : Layer(Layer), MR(std::move(MR)), ObjBuffer(std::move(ObjBuffer)) {}
+
+  JITLinkMemoryManager &getMemoryManager() override { return Layer.MemMgr; }
+
+  MemoryBufferRef getObjectBuffer() const override {
+    return ObjBuffer->getMemBufferRef();
+  }
+
+  void notifyFailed(Error Err) override {
+    Layer.getExecutionSession().reportError(std::move(Err));
+    MR.failMaterialization();
+  }
+
+  void lookup(const DenseSet<StringRef> &Symbols,
+              JITLinkAsyncLookupContinuation LookupContinuation) override {
+
+    JITDylibSearchList SearchOrder;
+    MR.getTargetJITDylib().withSearchOrderDo(
+        [&](const JITDylibSearchList &JDs) { SearchOrder = JDs; });
+
+    auto &ES = Layer.getExecutionSession();
+
+    SymbolNameSet InternedSymbols;
+    for (auto &S : Symbols)
+      InternedSymbols.insert(ES.intern(S));
+
+    // OnResolve -- De-intern the symbols and pass the result to the linker.
+    // FIXME: Capture LookupContinuation by move once we have c++14.
+    auto SharedLookupContinuation =
+        std::make_shared<JITLinkAsyncLookupContinuation>(
+            std::move(LookupContinuation));
+    auto OnResolve = [SharedLookupContinuation](Expected<SymbolMap> Result) {
+      if (!Result)
+        (*SharedLookupContinuation)(Result.takeError());
+      else {
+        AsyncLookupResult LR;
+        for (auto &KV : *Result)
+          LR[*KV.first] = KV.second;
+        (*SharedLookupContinuation)(std::move(LR));
+      }
+    };
+
+    ES.lookup(
+        SearchOrder, std::move(InternedSymbols), std::move(OnResolve),
+        // OnReady:
+        [&ES](Error Err) { ES.reportError(std::move(Err)); },
+        // RegisterDependencies:
+        [this](const SymbolDependenceMap &Deps) {
+          registerDependencies(Deps);
+        });
+  }
+
+  void notifyResolved(AtomGraph &G) override {
+    auto &ES = Layer.getExecutionSession();
+
+    SymbolFlagsMap ExtraSymbolsToClaim;
+    bool AutoClaim = Layer.AutoClaimObjectSymbols;
+
+    SymbolMap InternedResult;
+    for (auto *DA : G.defined_atoms())
+      if (DA->hasName() && DA->isGlobal()) {
+        auto InternedName = ES.intern(DA->getName());
+        JITSymbolFlags Flags;
+
+        if (DA->isExported())
+          Flags |= JITSymbolFlags::Exported;
+        if (DA->isWeak())
+          Flags |= JITSymbolFlags::Weak;
+        if (DA->isCallable())
+          Flags |= JITSymbolFlags::Callable;
+        if (DA->isCommon())
+          Flags |= JITSymbolFlags::Common;
+
+        InternedResult[InternedName] =
+            JITEvaluatedSymbol(DA->getAddress(), Flags);
+        if (AutoClaim && !MR.getSymbols().count(InternedName)) {
+          assert(!ExtraSymbolsToClaim.count(InternedName) &&
+                 "Duplicate symbol to claim?");
+          ExtraSymbolsToClaim[InternedName] = Flags;
+        }
+      }
+
+    for (auto *A : G.absolute_atoms())
+      if (A->hasName()) {
+        auto InternedName = ES.intern(A->getName());
+        JITSymbolFlags Flags;
+        Flags |= JITSymbolFlags::Absolute;
+        if (A->isWeak())
+          Flags |= JITSymbolFlags::Weak;
+        if (A->isCallable())
+          Flags |= JITSymbolFlags::Callable;
+        InternedResult[InternedName] =
+            JITEvaluatedSymbol(A->getAddress(), Flags);
+        if (AutoClaim && !MR.getSymbols().count(InternedName)) {
+          assert(!ExtraSymbolsToClaim.count(InternedName) &&
+                 "Duplicate symbol to claim?");
+          ExtraSymbolsToClaim[InternedName] = Flags;
+        }
+      }
+
+    if (!ExtraSymbolsToClaim.empty())
+      if (auto Err = MR.defineMaterializing(ExtraSymbolsToClaim))
+        return notifyFailed(std::move(Err));
+
+    MR.resolve(InternedResult);
+
+    if (Layer.NotifyLoaded)
+      Layer.NotifyLoaded(MR.getVModuleKey());
+  }
+
+  void notifyFinalized(
+      std::unique_ptr<JITLinkMemoryManager::Allocation> A) override {
+
+    if (EHFrameAddr) {
+      // If there is an eh-frame then try to register it.
+      if (auto Err = registerEHFrameSection((void *)EHFrameAddr)) {
+        Layer.getExecutionSession().reportError(std::move(Err));
+        MR.failMaterialization();
+        return;
+      }
+    }
+
+    MR.emit();
+    Layer.notifyFinalized(
+        ObjectLinkingLayer::ObjectResources(std::move(A), EHFrameAddr));
+  }
+
+  AtomGraphPassFunction getMarkLivePass(const Triple &TT) const override {
+    return [this](AtomGraph &G) { return markResponsibilitySymbolsLive(G); };
+  }
+
+  Error modifyPassConfig(const Triple &TT, PassConfiguration &Config) override {
+    // Add passes to mark duplicate defs as should-discard, and to walk the
+    // atom graph to build the symbol dependence graph.
+    Config.PrePrunePasses.push_back(
+        [this](AtomGraph &G) { return markSymbolsToDiscard(G); });
+    Config.PostPrunePasses.push_back(
+        [this](AtomGraph &G) { return computeNamedSymbolDependencies(G); });
+
+    Config.PostFixupPasses.push_back(
+        createEHFrameRecorderPass(TT, EHFrameAddr));
+
+    if (Layer.ModifyPassConfig)
+      Layer.ModifyPassConfig(TT, Config);
+
+    return Error::success();
+  }
+
+private:
+  using AnonAtomNamedDependenciesMap =
+      DenseMap<const DefinedAtom *, SymbolNameSet>;
+
+  Error markSymbolsToDiscard(AtomGraph &G) {
+    auto &ES = Layer.getExecutionSession();
+    for (auto *DA : G.defined_atoms())
+      if (DA->isWeak() && DA->hasName()) {
+        auto S = ES.intern(DA->getName());
+        auto I = MR.getSymbols().find(S);
+        if (I == MR.getSymbols().end())
+          DA->setShouldDiscard(true);
+      }
+
+    for (auto *A : G.absolute_atoms())
+      if (A->isWeak() && A->hasName()) {
+        auto S = ES.intern(A->getName());
+        auto I = MR.getSymbols().find(S);
+        if (I == MR.getSymbols().end())
+          A->setShouldDiscard(true);
+      }
+
+    return Error::success();
+  }
+
+  Error markResponsibilitySymbolsLive(AtomGraph &G) const {
+    auto &ES = Layer.getExecutionSession();
+    for (auto *DA : G.defined_atoms())
+      if (DA->hasName() &&
+          MR.getSymbols().count(ES.intern(DA->getName())))
+        DA->setLive(true);
+    return Error::success();
+  }
+
+  Error computeNamedSymbolDependencies(AtomGraph &G) {
+    auto &ES = MR.getTargetJITDylib().getExecutionSession();
+    auto AnonDeps = computeAnonDeps(G);
+
+    for (auto *DA : G.defined_atoms()) {
+
+      // Skip anonymous and non-global atoms: we do not need dependencies for
+      // these.
+      if (!DA->hasName() || !DA->isGlobal())
+        continue;
+
+      auto DAName = ES.intern(DA->getName());
+      SymbolNameSet &DADeps = NamedSymbolDeps[DAName];
+
+      for (auto &E : DA->edges()) {
+        auto &TA = E.getTarget();
+
+        if (TA.hasName())
+          DADeps.insert(ES.intern(TA.getName()));
+        else {
+          assert(TA.isDefined() && "Anonymous atoms must be defined");
+          auto &DTA = static_cast<DefinedAtom &>(TA);
+          auto I = AnonDeps.find(&DTA);
+          if (I != AnonDeps.end())
+            for (auto &S : I->second)
+              DADeps.insert(S);
+        }
+      }
+    }
+
+    return Error::success();
+  }
+
+  AnonAtomNamedDependenciesMap computeAnonDeps(AtomGraph &G) {
+
+    auto &ES = MR.getTargetJITDylib().getExecutionSession();
+    AnonAtomNamedDependenciesMap DepMap;
+
+    // For all anonymous atoms:
+    // (1) Add their named dependencies.
+    // (2) Add them to the worklist for further iteration if they have any
+    //     depend on any other anonymous atoms.
+    struct WorklistEntry {
+      WorklistEntry(DefinedAtom *DA, DenseSet<DefinedAtom *> DAAnonDeps)
+          : DA(DA), DAAnonDeps(std::move(DAAnonDeps)) {}
+
+      DefinedAtom *DA = nullptr;
+      DenseSet<DefinedAtom *> DAAnonDeps;
+    };
+    std::vector<WorklistEntry> Worklist;
+    for (auto *DA : G.defined_atoms())
+      if (!DA->hasName()) {
+        auto &DANamedDeps = DepMap[DA];
+        DenseSet<DefinedAtom *> DAAnonDeps;
+
+        for (auto &E : DA->edges()) {
+          auto &TA = E.getTarget();
+          if (TA.hasName())
+            DANamedDeps.insert(ES.intern(TA.getName()));
+          else {
+            assert(TA.isDefined() && "Anonymous atoms must be defined");
+            DAAnonDeps.insert(static_cast<DefinedAtom *>(&TA));
+          }
+        }
+
+        if (!DAAnonDeps.empty())
+          Worklist.push_back(WorklistEntry(DA, std::move(DAAnonDeps)));
+      }
+
+    // Loop over all anonymous atoms with anonymous dependencies, propagating
+    // their respective *named* dependencies. Iterate until we hit a stable
+    // state.
+    bool Changed;
+    do {
+      Changed = false;
+      for (auto &WLEntry : Worklist) {
+        auto *DA = WLEntry.DA;
+        auto &DANamedDeps = DepMap[DA];
+        auto &DAAnonDeps = WLEntry.DAAnonDeps;
+
+        for (auto *TA : DAAnonDeps) {
+          auto I = DepMap.find(TA);
+          if (I != DepMap.end())
+            for (const auto &S : I->second)
+              Changed |= DANamedDeps.insert(S).second;
+        }
+      }
+    } while (Changed);
+
+    return DepMap;
+  }
+
+  void registerDependencies(const SymbolDependenceMap &QueryDeps) {
+    for (auto &NamedDepsEntry : NamedSymbolDeps) {
+      auto &Name = NamedDepsEntry.first;
+      auto &NameDeps = NamedDepsEntry.second;
+      SymbolDependenceMap SymbolDeps;
+
+      for (const auto &QueryDepsEntry : QueryDeps) {
+        JITDylib &SourceJD = *QueryDepsEntry.first;
+        const SymbolNameSet &Symbols = QueryDepsEntry.second;
+        auto &DepsForJD = SymbolDeps[&SourceJD];
+
+        for (const auto &S : Symbols)
+          if (NameDeps.count(S))
+            DepsForJD.insert(S);
+
+        if (DepsForJD.empty())
+          SymbolDeps.erase(&SourceJD);
+      }
+
+      MR.addDependencies(Name, SymbolDeps);
+    }
+  }
+
+  ObjectLinkingLayer &Layer;
+  MaterializationResponsibility MR;
+  std::unique_ptr<MemoryBuffer> ObjBuffer;
+  DenseMap<SymbolStringPtr, SymbolNameSet> NamedSymbolDeps;
+  JITTargetAddress EHFrameAddr = 0;
+};
+
+ObjectLinkingLayer::ObjectLinkingLayer(
+    ExecutionSession &ES, JITLinkMemoryManager &MemMgr,
+    NotifyLoadedFunction NotifyLoaded, NotifyEmittedFunction NotifyEmitted,
+    ModifyPassConfigFunction ModifyPassConfig)
+    : ObjectLayer(ES), MemMgr(MemMgr), NotifyLoaded(std::move(NotifyLoaded)),
+      NotifyEmitted(std::move(NotifyEmitted)),
+      ModifyPassConfig(std::move(ModifyPassConfig)) {}
+
+void ObjectLinkingLayer::emit(MaterializationResponsibility R,
+                              std::unique_ptr<MemoryBuffer> O) {
+  assert(O && "Object must not be null");
+  jitLink(llvm::make_unique<ObjectLinkingLayerJITLinkContext>(
+      *this, std::move(R), std::move(O)));
+}
+
+ObjectLinkingLayer::ObjectResources::ObjectResources(
+    AllocPtr Alloc, JITTargetAddress EHFrameAddr)
+    : Alloc(std::move(Alloc)), EHFrameAddr(EHFrameAddr) {}
+
+ObjectLinkingLayer::ObjectResources::ObjectResources(ObjectResources &&Other)
+    : Alloc(std::move(Other.Alloc)), EHFrameAddr(Other.EHFrameAddr) {
+  Other.EHFrameAddr = 0;
+}
+
+ObjectLinkingLayer::ObjectResources &
+ObjectLinkingLayer::ObjectResources::operator=(ObjectResources &&Other) {
+  std::swap(Alloc, Other.Alloc);
+  std::swap(EHFrameAddr, Other.EHFrameAddr);
+  return *this;
+}
+
+ObjectLinkingLayer::ObjectResources::~ObjectResources() {
+  const char *ErrBanner =
+      "ObjectLinkingLayer received error deallocating object resources:";
+
+  assert((EHFrameAddr == 0 || Alloc) &&
+         "Non-null EHFrameAddr must have an associated allocation");
+
+  if (EHFrameAddr)
+    if (auto Err = deregisterEHFrameSection((void *)EHFrameAddr))
+      logAllUnhandledErrors(std::move(Err), llvm::errs(), ErrBanner);
+
+  if (Alloc)
+    if (auto Err = Alloc->deallocate())
+      logAllUnhandledErrors(std::move(Err), llvm::errs(), ErrBanner);
+}
+
+} // End namespace orc.
+} // End namespace llvm.