--- a/include/llvm/Bitcode/BitstreamWriter.h	Fri Nov 25 19:14:25 2016 +0900
+++ b/include/llvm/Bitcode/BitstreamWriter.h	Fri Oct 27 17:07:41 2017 +0900
@@ -43,12 +43,12 @@
   unsigned BlockInfoCurBID;
 
   /// CurAbbrevs - Abbrevs installed at in this block.
-  std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> CurAbbrevs;
+  std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs;
 
   struct Block {
     unsigned PrevCodeSize;
     size_t StartSizeWord;
-    std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> PrevAbbrevs;
+    std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs;
     Block(unsigned PCS, size_t SSW) : PrevCodeSize(PCS), StartSizeWord(SSW) {}
   };
 
@@ -59,7 +59,7 @@
   /// These describe abbreviations that all blocks of the specified ID inherit.
   struct BlockInfo {
     unsigned BlockID;
-    std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> Abbrevs;
+    std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs;
   };
   std::vector<BlockInfo> BlockInfoRecords;
 
@@ -112,6 +112,11 @@
         &Out[ByteNo], NewWord, BitNo & 7);
   }
 
+  void BackpatchWord64(uint64_t BitNo, uint64_t Val) {
+    BackpatchWord(BitNo, (uint32_t)Val);
+    BackpatchWord(BitNo + 32, (uint32_t)(Val >> 32));
+  }
+
   void Emit(uint32_t Val, unsigned NumBits) {
     assert(NumBits && NumBits <= 32 && "Invalid value size!");
     assert((Val & ~(~0U >> (32-NumBits))) == 0 && "High bits set!");
@@ -131,15 +136,6 @@
     CurBit = (CurBit+NumBits) & 31;
   }
 
-  void Emit64(uint64_t Val, unsigned NumBits) {
-    if (NumBits <= 32)
-      Emit((uint32_t)Val, NumBits);
-    else {
-      Emit((uint32_t)Val, 32);
-      Emit((uint32_t)(Val >> 32), NumBits-32);
-    }
-  }
-
   void FlushToWord() {
     if (CurBit) {
       WriteWord(CurValue);
@@ -473,12 +469,12 @@
 
 private:
   // Emit the abbreviation as a DEFINE_ABBREV record.
-  void EncodeAbbrev(BitCodeAbbrev *Abbv) {
+  void EncodeAbbrev(const BitCodeAbbrev &Abbv) {
     EmitCode(bitc::DEFINE_ABBREV);
-    EmitVBR(Abbv->getNumOperandInfos(), 5);
-    for (unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
+    EmitVBR(Abbv.getNumOperandInfos(), 5);
+    for (unsigned i = 0, e = static_cast<unsigned>(Abbv.getNumOperandInfos());
          i != e; ++i) {
-      const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
+      const BitCodeAbbrevOp &Op = Abbv.getOperandInfo(i);
       Emit(Op.isLiteral(), 1);
       if (Op.isLiteral()) {
         EmitVBR64(Op.getLiteralValue(), 8);
@@ -493,10 +489,10 @@
 
   /// EmitAbbrev - This emits an abbreviation to the stream.  Note that this
   /// method takes ownership of the specified abbrev.
-  unsigned EmitAbbrev(BitCodeAbbrev *Abbv) {
+  unsigned EmitAbbrev(std::shared_ptr<BitCodeAbbrev> Abbv) {
     // Emit the abbreviation as a record.
-    EncodeAbbrev(Abbv);
-    CurAbbrevs.push_back(Abbv);
+    EncodeAbbrev(*Abbv);
+    CurAbbrevs.push_back(std::move(Abbv));
     return static_cast<unsigned>(CurAbbrevs.size())-1 +
       bitc::FIRST_APPLICATION_ABBREV;
   }
@@ -509,6 +505,7 @@
   void EnterBlockInfoBlock() {
     EnterSubblock(bitc::BLOCKINFO_BLOCK_ID, 2);
     BlockInfoCurBID = ~0U;
+    BlockInfoRecords.clear();
   }
 private:
   /// SwitchToBlockID - If we aren't already talking about the specified block
@@ -535,13 +532,13 @@
 
   /// EmitBlockInfoAbbrev - Emit a DEFINE_ABBREV record for the specified
   /// BlockID.
-  unsigned EmitBlockInfoAbbrev(unsigned BlockID, BitCodeAbbrev *Abbv) {
+  unsigned EmitBlockInfoAbbrev(unsigned BlockID, std::shared_ptr<BitCodeAbbrev> Abbv) {
     SwitchToBlockID(BlockID);
-    EncodeAbbrev(Abbv);
+    EncodeAbbrev(*Abbv);
 
     // Add the abbrev to the specified block record.
     BlockInfo &Info = getOrCreateBlockInfo(BlockID);
-    Info.Abbrevs.push_back(Abbv);
+    Info.Abbrevs.push_back(std::move(Abbv));
 
     return Info.Abbrevs.size()-1+bitc::FIRST_APPLICATION_ABBREV;
   }