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diff --git a/llvm/lib/Bitcode/Reader/ValueList.h b/llvm/lib/Bitcode/Reader/ValueList.h
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index 00000000000..3119d7735e2
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+++ b/llvm/lib/Bitcode/Reader/ValueList.h
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+//===-- Bitcode/Reader/ValueEnumerator.h - Number values --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This class gives values and types Unique ID's.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/ValueHandle.h"
+
+#include <vector>
+
+namespace llvm {
+class Constant;
+
+class BitcodeReaderValueList {
+  std::vector<WeakVH> ValuePtrs;
+
+  /// As we resolve forward-referenced constants, we add information about them
+  /// to this vector.  This allows us to resolve them in bulk instead of
+  /// resolving each reference at a time.  See the code in
+  /// ResolveConstantForwardRefs for more information about this.
+  ///
+  /// The key of this vector is the placeholder constant, the value is the slot
+  /// number that holds the resolved value.
+  typedef std::vector<std::pair<Constant *, unsigned>> ResolveConstantsTy;
+  ResolveConstantsTy ResolveConstants;
+  LLVMContext &Context;
+
+public:
+  BitcodeReaderValueList(LLVMContext &C) : Context(C) {}
+  ~BitcodeReaderValueList() {
+    assert(ResolveConstants.empty() && "Constants not resolved?");
+  }
+
+  // vector compatibility methods
+  unsigned size() const { return ValuePtrs.size(); }
+  void resize(unsigned N) { ValuePtrs.resize(N); }
+  void push_back(Value *V) { ValuePtrs.emplace_back(V); }
+
+  void clear() {
+    assert(ResolveConstants.empty() && "Constants not resolved?");
+    ValuePtrs.clear();
+  }
+
+  Value *operator[](unsigned i) const {
+    assert(i < ValuePtrs.size());
+    return ValuePtrs[i];
+  }
+
+  Value *back() const { return ValuePtrs.back(); }
+  void pop_back() { ValuePtrs.pop_back(); }
+  bool empty() const { return ValuePtrs.empty(); }
+
+  void shrinkTo(unsigned N) {
+    assert(N <= size() && "Invalid shrinkTo request!");
+    ValuePtrs.resize(N);
+  }
+
+  Constant *getConstantFwdRef(unsigned Idx, Type *Ty);
+  Value *getValueFwdRef(unsigned Idx, Type *Ty);
+
+  void assignValue(Value *V, unsigned Idx);
+
+  /// Once all constants are read, this method bulk resolves any forward
+  /// references.
+  void resolveConstantForwardRefs();
+};
+
+} // namespace llvm