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diff --git a/lib/ReaderWriter/MachO/GOTPass.cpp b/lib/ReaderWriter/MachO/GOTPass.cpp
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+++ b/lib/ReaderWriter/MachO/GOTPass.cpp
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+//===- lib/ReaderWriter/MachO/GOTPass.cpp ---------------------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This linker pass transforms all GOT kind references to real references.
+/// That is, in assembly you can write something like:
+///     movq foo@GOTPCREL(%rip), %rax
+/// which means you want to load a pointer to "foo" out of the GOT (global
+/// Offsets Table). In the object file, the Atom containing this instruction
+/// has a Reference whose target is an Atom named "foo" and the Reference
+/// kind is a GOT load.  The linker needs to instantiate a pointer sized
+/// GOT entry.  This is done be creating a GOT Atom to represent that pointer
+/// sized data in this pass, and altering the Atom graph so the Reference now
+/// points to the GOT Atom entry (corresponding to "foo") and changing the
+/// Reference Kind to reflect it is now pointing to a GOT entry (rather
+/// then needing a GOT entry).
+///
+/// There is one optimization the linker can do here.  If the target of the GOT
+/// is in the same linkage unit and does not need to be interposable, and
+/// the GOT use is just a load (not some other operation), this pass can
+/// transform that load into an LEA (add).  This optimizes away one memory load
+/// which at runtime that could stall the pipeline.  This optimization only
+/// works for architectures in which a (GOT) load instruction can be change to
+/// an LEA instruction that is the same size.  The method isGOTAccess() should
+/// only return true for "canBypassGOT" if this optimization is supported.
+///
+//===----------------------------------------------------------------------===//
+
+#include "ArchHandler.h"
+#include "File.h"
+#include "MachOPasses.h"
+#include "lld/Core/DefinedAtom.h"
+#include "lld/Core/File.h"
+#include "lld/Core/LLVM.h"
+#include "lld/Core/Reference.h"
+#include "lld/Core/Simple.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/STLExtras.h"
+
+namespace lld {
+namespace mach_o {
+
+
+//
+//  GOT Entry Atom created by the GOT pass.
+//
+class GOTEntryAtom : public SimpleDefinedAtom {
+public:
+  GOTEntryAtom(const File &file, bool is64, StringRef name)
+    : SimpleDefinedAtom(file), _is64(is64), _name(name) { }
+
+  ContentType contentType() const override {
+    return DefinedAtom::typeGOT;
+  }
+
+  Alignment alignment() const override {
+    return Alignment(_is64 ? 3 : 2);
+  }
+
+  uint64_t size() const override {
+    return _is64 ? 8 : 4;
+  }
+
+  ContentPermissions permissions() const override {
+    return DefinedAtom::permRW_;
+  }
+
+  ArrayRef<uint8_t> rawContent() const override {
+    static const uint8_t zeros[] =
+        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+    return llvm::makeArrayRef(zeros, size());
+  }
+
+  StringRef slotName() const {
+    return _name;
+  }
+
+private:
+  const bool _is64;
+  StringRef _name;
+};
+
+
+/// Pass for instantiating and optimizing GOT slots.
+///
+class GOTPass : public Pass {
+public:
+  GOTPass(const MachOLinkingContext &context)
+    : _context(context), _archHandler(_context.archHandler()),
+      _file("<mach-o GOT Pass>") { }
+
+private:
+
+  void perform(std::unique_ptr<MutableFile> &mergedFile) override {
+    // Scan all references in all atoms.
+    for (const DefinedAtom *atom : mergedFile->defined()) {
+      for (const Reference *ref : *atom) {
+        // Look at instructions accessing the GOT.
+        bool canBypassGOT;
+        if (!_archHandler.isGOTAccess(*ref, canBypassGOT))
+          continue;
+        const Atom *target = ref->target();
+        assert(target != nullptr);
+
+        if (!shouldReplaceTargetWithGOTAtom(target, canBypassGOT)) {
+          // Update reference kind to reflect that target is a direct accesss.
+          _archHandler.updateReferenceToGOT(ref, false);
+        } else {
+          // Replace the target with a reference to a GOT entry.
+          const DefinedAtom *gotEntry = makeGOTEntry(target);
+          const_cast<Reference *>(ref)->setTarget(gotEntry);
+          // Update reference kind to reflect that target is now a GOT entry.
+          _archHandler.updateReferenceToGOT(ref, true);
+        }
+      }
+    }
+
+    // Sort and add all created GOT Atoms to master file
+    std::vector<const GOTEntryAtom *> entries;
+    entries.reserve(_targetToGOT.size());
+    for (auto &it : _targetToGOT)
+      entries.push_back(it.second);
+    std::sort(entries.begin(), entries.end(),
+              [](const GOTEntryAtom *left, const GOTEntryAtom *right) {
+      return (left->slotName().compare(right->slotName()) < 0);
+    });
+    for (const GOTEntryAtom *slot : entries)
+      mergedFile->addAtom(*slot);
+  }
+
+  bool shouldReplaceTargetWithGOTAtom(const Atom *target, bool canBypassGOT) {
+    // Accesses to shared library symbols must go through GOT.
+    if (isa<SharedLibraryAtom>(target))
+      return true;
+    // Accesses to interposable symbols in same linkage unit must also go
+    // through GOT.
+    const DefinedAtom *defTarget = dyn_cast<DefinedAtom>(target);
+    if (defTarget != nullptr &&
+        defTarget->interposable() != DefinedAtom::interposeNo) {
+      assert(defTarget->scope() != DefinedAtom::scopeTranslationUnit);
+      return true;
+    }
+    // Target does not require indirection.  So, if instruction allows GOT to be
+    // by-passed, do that optimization and don't create GOT entry.
+    return !canBypassGOT;
+  }
+
+  const DefinedAtom *makeGOTEntry(const Atom *target) {
+    auto pos = _targetToGOT.find(target);
+    if (pos == _targetToGOT.end()) {
+      GOTEntryAtom *gotEntry = new (_file.allocator())
+          GOTEntryAtom(_file, _context.is64Bit(), target->name());
+      _targetToGOT[target] = gotEntry;
+      const ArchHandler::ReferenceInfo &nlInfo = _archHandler.stubInfo().
+                                                nonLazyPointerReferenceToBinder;
+      gotEntry->addReference(Reference::KindNamespace::mach_o, nlInfo.arch,
+                             nlInfo.kind, 0, target, 0);
+      return gotEntry;
+    }
+    return pos->second;
+  }
+
+
+  const MachOLinkingContext                       &_context;
+  mach_o::ArchHandler                             &_archHandler;
+  MachOFile                                        _file;
+  llvm::DenseMap<const Atom*, const GOTEntryAtom*> _targetToGOT;
+};
+
+
+
+void addGOTPass(PassManager &pm, const MachOLinkingContext &ctx) {
+  assert(ctx.needsGOTPass());
+  pm.add(llvm::make_unique<GOTPass>(ctx));
+}
+
+
+} // end namesapce mach_o
+} // end namesapce lld