4 files changed, 25 insertions, 9 deletions
diff --git a/include/llvm/Bitcode/BitCodes.h b/include/llvm/Bitcode/BitCodes.h
index 3f7a77d..96c4201 100644
--- a/include/llvm/Bitcode/BitCodes.h
+++ b/include/llvm/Bitcode/BitCodes.h
@@ -164,8 +164,8 @@ template <> struct isPodLike<BitCodeAbbrevOp> { static const bool value=true; };
 /// specialized format instead of the fully-general, fully-vbr, format.
 class BitCodeAbbrev : public RefCountedBase<BitCodeAbbrev> {
   SmallVector<BitCodeAbbrevOp, 32> OperandList;
-  ~BitCodeAbbrev() {}
   // Only RefCountedBase is allowed to delete.
+  ~BitCodeAbbrev() = default;
   friend class RefCountedBase<BitCodeAbbrev>;
 
 public:
diff --git a/include/llvm/Bitcode/BitcodeWriterPass.h b/include/llvm/Bitcode/BitcodeWriterPass.h
index 8fe9b7e..ae915c6 100644
--- a/include/llvm/Bitcode/BitcodeWriterPass.h
+++ b/include/llvm/Bitcode/BitcodeWriterPass.h
@@ -26,7 +26,11 @@ class PreservedAnalyses;
 /// \brief Create and return a pass that writes the module to the specified
 /// ostream. Note that this pass is designed for use with the legacy pass
 /// manager.
-ModulePass *createBitcodeWriterPass(raw_ostream &Str);
+///
+/// If \c ShouldPreserveUseListOrder, encode use-list order so it can be
+/// reproduced when deserialized.
+ModulePass *createBitcodeWriterPass(raw_ostream &Str,
+                                    bool ShouldPreserveUseListOrder = false);
 
 /// \brief Pass for writing a module of IR out to a bitcode file.
 ///
@@ -34,10 +38,16 @@ ModulePass *createBitcodeWriterPass(raw_ostream &Str);
 /// a pass for the legacy pass manager, use the function above.
 class BitcodeWriterPass {
   raw_ostream &OS;
+  bool ShouldPreserveUseListOrder;
 
 public:
   /// \brief Construct a bitcode writer pass around a particular output stream.
-  explicit BitcodeWriterPass(raw_ostream &OS) : OS(OS) {}
+  ///
+  /// If \c ShouldPreserveUseListOrder, encode use-list order so it can be
+  /// reproduced when deserialized.
+  explicit BitcodeWriterPass(raw_ostream &OS,
+                             bool ShouldPreserveUseListOrder = false)
+      : OS(OS), ShouldPreserveUseListOrder(ShouldPreserveUseListOrder) {}
 
   /// \brief Run the bitcode writer pass, and output the module to the selected
   /// output stream.
diff --git a/include/llvm/Bitcode/LLVMBitCodes.h b/include/llvm/Bitcode/LLVMBitCodes.h
index d842167..e450db0 100644
--- a/include/llvm/Bitcode/LLVMBitCodes.h
+++ b/include/llvm/Bitcode/LLVMBitCodes.h
@@ -397,7 +397,8 @@ namespace bitc {
     ATTR_KIND_IN_ALLOCA = 38,
     ATTR_KIND_NON_NULL = 39,
     ATTR_KIND_JUMP_TABLE = 40,
-    ATTR_KIND_DEREFERENCEABLE = 41
+    ATTR_KIND_DEREFERENCEABLE = 41,
+    ATTR_KIND_DEREFERENCEABLE_OR_NULL = 42
   };
 
   enum ComdatSelectionKindCodes {
diff --git a/include/llvm/Bitcode/ReaderWriter.h b/include/llvm/Bitcode/ReaderWriter.h
index 254949d..9d30098 100644
--- a/include/llvm/Bitcode/ReaderWriter.h
+++ b/include/llvm/Bitcode/ReaderWriter.h
@@ -56,11 +56,16 @@ namespace llvm {
   parseBitcodeFile(MemoryBufferRef Buffer, LLVMContext &Context,
                    DiagnosticHandlerFunction DiagnosticHandler = nullptr);
 
-  /// WriteBitcodeToFile - Write the specified module to the specified
-  /// raw output stream.  For streams where it matters, the given stream
-  /// should be in "binary" mode.
-  void WriteBitcodeToFile(const Module *M, raw_ostream &Out);
-
+  /// \brief Write the specified module to the specified raw output stream.
+  ///
+  /// For streams where it matters, the given stream should be in "binary"
+  /// mode.
+  ///
+  /// If \c ShouldPreserveUseListOrder, encode the use-list order for each \a
+  /// Value in \c M.  These will be reconstructed exactly when \a M is
+  /// deserialized.
+  void WriteBitcodeToFile(const Module *M, raw_ostream &Out,
+                          bool ShouldPreserveUseListOrder = false);
 
   /// isBitcodeWrapper - Return true if the given bytes are the magic bytes
   /// for an LLVM IR bitcode wrapper.