Rebased PNaCl localmods in LLVM to 223109

include/llvm/Bitcode/NaCl/NaClBitstreamWriter.h

-//===- BitstreamWriter.h - Low-level bitstream writer interface -*- C++ -*-===//
+//===- NaClBitstreamWriter.h - NaCl bitstream writer ------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This header defines the BitstreamWriter class.  This class can be used to
 // write an arbitrary bitstream, regardless of its contents.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_BITCODE_BITSTREAMWRITER_H
-#define LLVM_BITCODE_BITSTREAMWRITER_H
+#ifndef LLVM_BITCODE_NACL_NACLBITSTREAMWRITER_H
+#define LLVM_BITCODE_NACL_NACLBITSTREAMWRITER_H
 
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
-#include "llvm/Bitcode/BitCodes.h"
+#include "llvm/Bitcode/NaCl/NaClBitCodes.h"
 #include <vector>
 
 namespace llvm {
 
-class BitstreamWriter {
+class NaClBitstreamWriter {
   SmallVectorImpl<char> &Out;
 
   /// CurBit - Always between 0 and 31 inclusive, specifies the next bit to use.
   unsigned CurBit;
 
   /// CurValue - The current value.  Only bits < CurBit are valid.
   uint32_t CurValue;
 
   /// CurCodeSize - This is the declared size of code values used for the
   /// current block, in bits.
-  unsigned CurCodeSize;
+  NaClBitcodeSelectorAbbrev CurCodeSize;
 
   /// BlockInfoCurBID - When emitting a BLOCKINFO_BLOCK, this is the currently
   /// selected BLOCK ID.
   unsigned BlockInfoCurBID;
 
   /// CurAbbrevs - Abbrevs installed at in this block.
-  std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> CurAbbrevs;
+  std::vector<NaClBitCodeAbbrev*> CurAbbrevs;
 
   struct Block {
-    unsigned PrevCodeSize;
+    NaClBitcodeSelectorAbbrev PrevCodeSize;
     unsigned StartSizeWord;
-    std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> PrevAbbrevs;
-    Block(unsigned PCS, unsigned SSW) : PrevCodeSize(PCS), StartSizeWord(SSW) {}
+    std::vector<NaClBitCodeAbbrev*> PrevAbbrevs;
+    Block(const NaClBitcodeSelectorAbbrev& PCS, unsigned SSW)
+        : PrevCodeSize(PCS), StartSizeWord(SSW) {}
   };
 
   /// BlockScope - This tracks the current blocks that we have entered.
   std::vector<Block> BlockScope;
 
   /// BlockInfo - This contains information emitted to BLOCKINFO_BLOCK blocks.
   /// These describe abbreviations that all blocks of the specified ID inherit.
   struct BlockInfo {
     unsigned BlockID;
-    std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> Abbrevs;
+    std::vector<NaClBitCodeAbbrev*> Abbrevs;
   };
   std::vector<BlockInfo> BlockInfoRecords;
 
+  /// AbbrevValues - Wrapper class that allows the bitstream writer to
+  /// prefix a code to the set of values, associated with a record to
+  /// emit, without having to destructively change the contents of
+  /// values.
+  template<typename uintty>
+  struct AbbrevValues {
+    AbbrevValues(uintty Code, const SmallVectorImpl<uintty> &Values)
+        : Code(Code), Values(Values) {}
+
+    size_t size() const {
+      return Values.size() + 1;
+    }
+
+    uintty operator[](size_t Index) const {
+      return Index == 0 ? Code : Values[Index-1];
+    }
+
+  private:
+    // The code to use (if not DONT_USE_CODE).
+    uintty Code;
+    const SmallVectorImpl<uintty> &Values;
+  };
+
+public:
   // BackpatchWord - Backpatch a 32-bit word in the output with the specified
   // value.
   void BackpatchWord(unsigned ByteNo, unsigned NewWord) {
     Out[ByteNo++] = (unsigned char)(NewWord >>  0);
     Out[ByteNo++] = (unsigned char)(NewWord >>  8);
     Out[ByteNo++] = (unsigned char)(NewWord >> 16);
     Out[ByteNo  ] = (unsigned char)(NewWord >> 24);
   }
 
+private:
   void WriteByte(unsigned char Value) {
     Out.push_back(Value);
   }
 
   void WriteWord(unsigned Value) {
     unsigned char Bytes[4] = {
       (unsigned char)(Value >>  0),
       (unsigned char)(Value >>  8),
       (unsigned char)(Value >> 16),
       (unsigned char)(Value >> 24) };
     Out.append(&Bytes[0], &Bytes[4]);
   }
 
   unsigned GetBufferOffset() const {
     return Out.size();
   }
 
   unsigned GetWordIndex() const {
     unsigned Offset = GetBufferOffset();
     assert((Offset & 3) == 0 && "Not 32-bit aligned");
     return Offset / 4;
   }
 
 public:
-  explicit BitstreamWriter(SmallVectorImpl<char> &O)
-    : Out(O), CurBit(0), CurValue(0), CurCodeSize(2) {}
+  explicit NaClBitstreamWriter(SmallVectorImpl<char> &O)
+      : Out(O), CurBit(0), CurValue(0), CurCodeSize() {}
 
-  ~BitstreamWriter() {
-    assert(CurBit == 0 && "Unflushed data remaining");
+  ~NaClBitstreamWriter() {
+    assert(CurBit == 0 && "Unflused data remaining");
     assert(BlockScope.empty() && CurAbbrevs.empty() && "Block imbalance");
+
+    // Free the BlockInfoRecords.
+    while (!BlockInfoRecords.empty()) {
+      BlockInfo &Info = BlockInfoRecords.back();
+      // Free blockinfo abbrev info.
+      for (unsigned i = 0, e = static_cast<unsigned>(Info.Abbrevs.size());
+           i != e; ++i)
+        Info.Abbrevs[i]->dropRef();
+      BlockInfoRecords.pop_back();
+    }
   }
 
   /// \brief Retrieve the current position in the stream, in bits.
   uint64_t GetCurrentBitNo() const { return GetBufferOffset() * 8 + CurBit; }
 
   //===--------------------------------------------------------------------===//
   // Basic Primitives for emitting bits to the stream.
   //===--------------------------------------------------------------------===//
 
   void Emit(uint32_t Val, unsigned NumBits) {
@@ skipping 27 matching lines @@
   void FlushToWord() {
     if (CurBit) {
       WriteWord(CurValue);
       CurBit = 0;
       CurValue = 0;
     }
   }
 
   void EmitVBR(uint32_t Val, unsigned NumBits) {
     assert(NumBits <= 32 && "Too many bits to emit!");
+    assert(NumBits > 1 && "Too few bits to emit!");
     uint32_t Threshold = 1U << (NumBits-1);
 
     // Emit the bits with VBR encoding, NumBits-1 bits at a time.
     while (Val >= Threshold) {
       Emit((Val & ((1 << (NumBits-1))-1)) | (1 << (NumBits-1)), NumBits);
       Val >>= NumBits-1;
     }
 
     Emit(Val, NumBits);
   }
 
   void EmitVBR64(uint64_t Val, unsigned NumBits) {
     assert(NumBits <= 32 && "Too many bits to emit!");
+    assert(NumBits > 1 && "Too few bits to emit!");
     if ((uint32_t)Val == Val)
       return EmitVBR((uint32_t)Val, NumBits);
 
     uint32_t Threshold = 1U << (NumBits-1);
 
     // Emit the bits with VBR encoding, NumBits-1 bits at a time.
     while (Val >= Threshold) {
       Emit(((uint32_t)Val & ((1 << (NumBits-1))-1)) |
            (1 << (NumBits-1)), NumBits);
       Val >>= NumBits-1;
     }
 
     Emit((uint32_t)Val, NumBits);
   }
 
   /// EmitCode - Emit the specified code.
   void EmitCode(unsigned Val) {
-    Emit(Val, CurCodeSize);
+    if (CurCodeSize.IsFixed)
+      Emit(Val, CurCodeSize.NumBits);
+    else
+      EmitVBR(Val, CurCodeSize.NumBits);
   }
 
   //===--------------------------------------------------------------------===//
   // Block Manipulation
   //===--------------------------------------------------------------------===//
 
   /// getBlockInfo - If there is block info for the specified ID, return it,
   /// otherwise return null.
   BlockInfo *getBlockInfo(unsigned BlockID) {
     // Common case, the most recent entry matches BlockID.
     if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
       return &BlockInfoRecords.back();
 
     for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size());
          i != e; ++i)
       if (BlockInfoRecords[i].BlockID == BlockID)
         return &BlockInfoRecords[i];
-    return nullptr;
+    return 0;
   }
 
-  void EnterSubblock(unsigned BlockID, unsigned CodeLen) {
+private:
+  // Enter block using CodeLen bits to read the size of the code
+  // selector associated with the block.
+  void EnterSubblock(unsigned BlockID,
+                     const NaClBitcodeSelectorAbbrev& CodeLen,
+                     BlockInfo *Info) {
     // Block header:
     //    [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
-    EmitCode(bitc::ENTER_SUBBLOCK);
-    EmitVBR(BlockID, bitc::BlockIDWidth);
-    EmitVBR(CodeLen, bitc::CodeLenWidth);
+    EmitCode(naclbitc::ENTER_SUBBLOCK);
+    EmitVBR(BlockID, naclbitc::BlockIDWidth);
+    assert(CodeLen.IsFixed && "Block codelens must be fixed");
+    EmitVBR(CodeLen.NumBits, naclbitc::CodeLenWidth);
     FlushToWord();
 
     unsigned BlockSizeWordIndex = GetWordIndex();
-    unsigned OldCodeSize = CurCodeSize;
+    NaClBitcodeSelectorAbbrev OldCodeSize(CurCodeSize);
 
     // Emit a placeholder, which will be replaced when the block is popped.
-    Emit(0, bitc::BlockSizeWidth);
+    Emit(0, naclbitc::BlockSizeWidth);
 
     CurCodeSize = CodeLen;
 
     // Push the outer block's abbrev set onto the stack, start out with an
     // empty abbrev set.
     BlockScope.push_back(Block(OldCodeSize, BlockSizeWordIndex));
     BlockScope.back().PrevAbbrevs.swap(CurAbbrevs);
 
     // If there is a blockinfo for this BlockID, add all the predefined abbrevs
     // to the abbrev list.
-    if (BlockInfo *Info = getBlockInfo(BlockID)) {
-      CurAbbrevs.insert(CurAbbrevs.end(), Info->Abbrevs.begin(),
-                        Info->Abbrevs.end());
+    if (Info) {
+      for (unsigned i = 0, e = static_cast<unsigned>(Info->Abbrevs.size());
+           i != e; ++i) {
+        CurAbbrevs.push_back(Info->Abbrevs[i]);
+        Info->Abbrevs[i]->addRef();
+      }
     }
   }
 
+public:
+  /// \brief Enter block using CodeLen bits to read the size of the code
+  /// selector associated with the block.
+  void EnterSubblock(unsigned BlockID,
+                     const NaClBitcodeSelectorAbbrev& CodeLen) {
+    EnterSubblock(BlockID, CodeLen, getBlockInfo(BlockID));
+  }
+
+  /// \brief Enter block, using a code length based on the number of
+  /// (global) BlockInfo entries defined for the block. Note: This
+  /// should be used only if the block doesn't define any local abbreviations.
+  void EnterSubblock(unsigned BlockID) {
+    BlockInfo *Info = getBlockInfo(BlockID);
+    size_t NumAbbrevs = Info ? Info->Abbrevs.size() : 0;
+    NaClBitcodeSelectorAbbrev DefaultCodeLen(
+        naclbitc::DEFAULT_MAX_ABBREV+NumAbbrevs);
+    EnterSubblock(BlockID, DefaultCodeLen, Info);
+  }
+
+  /// \brief Enter block with the given number of abbreviations.
+  void EnterSubblock(unsigned BlockID, unsigned NumAbbrev) {
+    NaClBitcodeSelectorAbbrev CodeLenAbbrev(NumAbbrev);
+    EnterSubblock(BlockID, CodeLenAbbrev);
+  }
+
   void ExitBlock() {
     assert(!BlockScope.empty() && "Block scope imbalance!");
+
+    // Delete all abbrevs.
+    for (unsigned i = 0, e = static_cast<unsigned>(CurAbbrevs.size());
+         i != e; ++i)
+      CurAbbrevs[i]->dropRef();
+
     const Block &B = BlockScope.back();
 
     // Block tail:
     //    [END_BLOCK, <align4bytes>]
-    EmitCode(bitc::END_BLOCK);
+    EmitCode(naclbitc::END_BLOCK);
     FlushToWord();
 
     // Compute the size of the block, in words, not counting the size field.
     unsigned SizeInWords = GetWordIndex() - B.StartSizeWord - 1;
     unsigned ByteNo = B.StartSizeWord*4;
 
     // Update the block size field in the header of this sub-block.
     BackpatchWord(ByteNo, SizeInWords);
 
     // Restore the inner block's code size and abbrev table.
     CurCodeSize = B.PrevCodeSize;
-    CurAbbrevs = std::move(B.PrevAbbrevs);
+    BlockScope.back().PrevAbbrevs.swap(CurAbbrevs);
     BlockScope.pop_back();
   }
 
   //===--------------------------------------------------------------------===//
   // Record Emission
   //===--------------------------------------------------------------------===//
 
 private:
-  /// EmitAbbreviatedLiteral - Emit a literal value according to its abbrev
-  /// record.  This is a no-op, since the abbrev specifies the literal to use.
-  template<typename uintty>
-  void EmitAbbreviatedLiteral(const BitCodeAbbrevOp &Op, uintty V) {
-    assert(Op.isLiteral() && "Not a literal");
-    // If the abbrev specifies the literal value to use, don't emit
-    // anything.
-    assert(V == Op.getLiteralValue() &&
-           "Invalid abbrev for record!");
-  }
-
   /// EmitAbbreviatedField - Emit a single scalar field value with the specified
   /// encoding.
   template<typename uintty>
-  void EmitAbbreviatedField(const BitCodeAbbrevOp &Op, uintty V) {
-    assert(!Op.isLiteral() && "Literals should use EmitAbbreviatedLiteral!");
-
-    // Encode the value as we are commanded.
+  void EmitAbbreviatedField(const NaClBitCodeAbbrevOp &Op, uintty V) {
     switch (Op.getEncoding()) {
-    default: llvm_unreachable("Unknown encoding!");
-    case BitCodeAbbrevOp::Fixed:
-      if (Op.getEncodingData())
-        Emit((unsigned)V, (unsigned)Op.getEncodingData());
+    case NaClBitCodeAbbrevOp::Literal:
+      // This is a no-op, since the abbrev specifies the literal to use.
+      assert(V == Op.getValue() && "Invalid abbrev for record!");
       break;
-    case BitCodeAbbrevOp::VBR:
-      if (Op.getEncodingData())
-        EmitVBR64(V, (unsigned)Op.getEncodingData());
+    case NaClBitCodeAbbrevOp::Fixed:
+      if (Op.getValue())
+        Emit((unsigned)V, (unsigned)Op.getValue());
       break;
-    case BitCodeAbbrevOp::Char6:
-      Emit(BitCodeAbbrevOp::EncodeChar6((char)V), 6);
+    case NaClBitCodeAbbrevOp::VBR:
+      if (Op.getValue())
+        EmitVBR64(V, (unsigned)Op.getValue());
+      break;
+    case NaClBitCodeAbbrevOp::Array:
+      report_fatal_error("Not to be used with array abbreviation op!");
+    case NaClBitCodeAbbrevOp::Char6:
+      Emit(NaClBitCodeAbbrevOp::EncodeChar6((char)V), 6);
       break;
     }
   }
 
   /// EmitRecordWithAbbrevImpl - This is the core implementation of the record
-  /// emission code.  If BlobData is non-null, then it specifies an array of
-  /// data that should be emitted as part of the Blob or Array operand that is
-  /// known to exist at the end of the record.
+  /// emission code.
   template<typename uintty>
-  void EmitRecordWithAbbrevImpl(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
-                                StringRef Blob) {
-    const char *BlobData = Blob.data();
-    unsigned BlobLen = (unsigned) Blob.size();
-    unsigned AbbrevNo = Abbrev-bitc::FIRST_APPLICATION_ABBREV;
+  void EmitRecordWithAbbrevImpl(unsigned Abbrev,
+                                const AbbrevValues<uintty> &Vals) {
+    unsigned AbbrevNo = Abbrev-naclbitc::FIRST_APPLICATION_ABBREV;
     assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
-    const BitCodeAbbrev *Abbv = CurAbbrevs[AbbrevNo].get();
+    NaClBitCodeAbbrev *Abbv = CurAbbrevs[AbbrevNo];
 
     EmitCode(Abbrev);
 
     unsigned RecordIdx = 0;
     for (unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
          i != e; ++i) {
-      const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
-      if (Op.isLiteral()) {
-        assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
-        EmitAbbreviatedLiteral(Op, Vals[RecordIdx]);
-        ++RecordIdx;
-      } else if (Op.getEncoding() == BitCodeAbbrevOp::Array) {
+      const NaClBitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
+      if (Op.getEncoding() == NaClBitCodeAbbrevOp::Array) {
         // Array case.
         assert(i+2 == e && "array op not second to last?");
-        const BitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
-
-        // If this record has blob data, emit it, otherwise we must have record
-        // entries to encode this way.
-        if (BlobData) {
-          assert(RecordIdx == Vals.size() &&
-                 "Blob data and record entries specified for array!");
-          // Emit a vbr6 to indicate the number of elements present.
-          EmitVBR(static_cast<uint32_t>(BlobLen), 6);
-
-          // Emit each field.
-          for (unsigned i = 0; i != BlobLen; ++i)
-            EmitAbbreviatedField(EltEnc, (unsigned char)BlobData[i]);
-
-          // Know that blob data is consumed for assertion below.
-          BlobData = nullptr;
-        } else {
-          // Emit a vbr6 to indicate the number of elements present.
-          EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
-
-          // Emit each field.
-          for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx)
-            EmitAbbreviatedField(EltEnc, Vals[RecordIdx]);
-        }
-      } else if (Op.getEncoding() == BitCodeAbbrevOp::Blob) {
-        // If this record has blob data, emit it, otherwise we must have record
-        // entries to encode this way.
+        const NaClBitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
 
         // Emit a vbr6 to indicate the number of elements present.
-        if (BlobData) {
-          EmitVBR(static_cast<uint32_t>(BlobLen), 6);
-          assert(RecordIdx == Vals.size() &&
-                 "Blob data and record entries specified for blob operand!");
-        } else {
-          EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
-        }
+        EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
 
-        // Flush to a 32-bit alignment boundary.
-        FlushToWord();
-
-        // Emit each field as a literal byte.
-        if (BlobData) {
-          for (unsigned i = 0; i != BlobLen; ++i)
-            WriteByte((unsigned char)BlobData[i]);
-
-          // Know that blob data is consumed for assertion below.
-          BlobData = nullptr;
-        } else {
-          for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx) {
-            assert(isUInt<8>(Vals[RecordIdx]) &&
-                   "Value too large to emit as blob");
-            WriteByte((unsigned char)Vals[RecordIdx]);
-          }
-        }
-
-        // Align end to 32-bits.
-        while (GetBufferOffset() & 3)
-          WriteByte(0);
-      } else {  // Single scalar field.
+        // Emit each field.
+        for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx)
+          EmitAbbreviatedField(EltEnc, Vals[RecordIdx]);
+      } else {
         assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
         EmitAbbreviatedField(Op, Vals[RecordIdx]);
         ++RecordIdx;
       }
     }
     assert(RecordIdx == Vals.size() && "Not all record operands emitted!");
-    assert(BlobData == nullptr &&
-           "Blob data specified for record that doesn't use it!");
   }
 
 public:
 
+  /// Returns true if the given abbreviation index corresponds to a user-defined
+  /// abbreviation.
+  bool isUserRecordAbbreviation(unsigned Abbrev) const {
+    return Abbrev >= naclbitc::FIRST_APPLICATION_ABBREV
+        && Abbrev < CurAbbrevs.size();
+  }
+
   /// EmitRecord - Emit the specified record to the stream, using an abbrev if
   /// we have one to compress the output.
   template<typename uintty>
-  void EmitRecord(unsigned Code, SmallVectorImpl<uintty> &Vals,
+  void EmitRecord(unsigned Code, const SmallVectorImpl<uintty> &Vals,
                   unsigned Abbrev = 0) {
     if (!Abbrev) {
       // If we don't have an abbrev to use, emit this in its fully unabbreviated
       // form.
-      EmitCode(bitc::UNABBREV_RECORD);
+      EmitCode(naclbitc::UNABBREV_RECORD);
       EmitVBR(Code, 6);
       EmitVBR(static_cast<uint32_t>(Vals.size()), 6);
       for (unsigned i = 0, e = static_cast<unsigned>(Vals.size()); i != e; ++i)
         EmitVBR64(Vals[i], 6);
       return;
     }
 
-    // Insert the code into Vals to treat it uniformly.
-    Vals.insert(Vals.begin(), Code);
-
-    EmitRecordWithAbbrev(Abbrev, Vals);
-  }
-
-  /// EmitRecordWithAbbrev - Emit a record with the specified abbreviation.
-  /// Unlike EmitRecord, the code for the record should be included in Vals as
-  /// the first entry.
-  template<typename uintty>
-  void EmitRecordWithAbbrev(unsigned Abbrev, SmallVectorImpl<uintty> &Vals) {
-    EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef());
-  }
-
-  /// EmitRecordWithBlob - Emit the specified record to the stream, using an
-  /// abbrev that includes a blob at the end.  The blob data to emit is
-  /// specified by the pointer and length specified at the end.  In contrast to
-  /// EmitRecord, this routine expects that the first entry in Vals is the code
-  /// of the record.
-  template<typename uintty>
-  void EmitRecordWithBlob(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
-                          StringRef Blob) {
-    EmitRecordWithAbbrevImpl(Abbrev, Vals, Blob);
-  }
-  template<typename uintty>
-  void EmitRecordWithBlob(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
-                          const char *BlobData, unsigned BlobLen) {
-    return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(BlobData, BlobLen));
-  }
-
-  /// EmitRecordWithArray - Just like EmitRecordWithBlob, works with records
-  /// that end with an array.
-  template<typename uintty>
-  void EmitRecordWithArray(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
-                          StringRef Array) {
-    EmitRecordWithAbbrevImpl(Abbrev, Vals, Array);
-  }
-  template<typename uintty>
-  void EmitRecordWithArray(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
-                          const char *ArrayData, unsigned ArrayLen) {
-    return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(ArrayData,
-                                                            ArrayLen));
+    // combine code and values, and then emit.
+    AbbrevValues<uintty> AbbrevVals(Code, Vals);
+    EmitRecordWithAbbrevImpl(Abbrev, AbbrevVals);
   }
 
   //===--------------------------------------------------------------------===//
   // Abbrev Emission
   //===--------------------------------------------------------------------===//
 
 private:
   // Emit the abbreviation as a DEFINE_ABBREV record.
-  void EncodeAbbrev(BitCodeAbbrev *Abbv) {
-    EmitCode(bitc::DEFINE_ABBREV);
+  void EncodeAbbrev(NaClBitCodeAbbrev *Abbv) {
+    EmitCode(naclbitc::DEFINE_ABBREV);
     EmitVBR(Abbv->getNumOperandInfos(), 5);
     for (unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
          i != e; ++i) {
-      const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
-      Emit(Op.isLiteral(), 1);
-      if (Op.isLiteral()) {
-        EmitVBR64(Op.getLiteralValue(), 8);
+      const NaClBitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
+      bool IsLiteral = Op.isLiteral();
+      Emit(IsLiteral, 1);
+      if (IsLiteral) {
+        EmitVBR64(Op.getValue(), 8);
       } else {
         Emit(Op.getEncoding(), 3);
-        if (Op.hasEncodingData())
-          EmitVBR64(Op.getEncodingData(), 5);
+        if (Op.hasValue())
+          EmitVBR64(Op.getValue(), 5);
       }
     }
   }
 public:
 
   /// EmitAbbrev - This emits an abbreviation to the stream.  Note that this
   /// method takes ownership of the specified abbrev.
-  unsigned EmitAbbrev(BitCodeAbbrev *Abbv) {
+  unsigned EmitAbbrev(NaClBitCodeAbbrev *Abbv) {
+    assert(Abbv->isValid() && "Can't emit invalid abbreviation!");
     // Emit the abbreviation as a record.
     EncodeAbbrev(Abbv);
     CurAbbrevs.push_back(Abbv);
     return static_cast<unsigned>(CurAbbrevs.size())-1 +
-      bitc::FIRST_APPLICATION_ABBREV;
+      naclbitc::FIRST_APPLICATION_ABBREV;
   }
 
   //===--------------------------------------------------------------------===//
   // BlockInfo Block Emission
   //===--------------------------------------------------------------------===//
 
   /// EnterBlockInfoBlock - Start emitting the BLOCKINFO_BLOCK.
-  void EnterBlockInfoBlock(unsigned CodeWidth) {
-    EnterSubblock(bitc::BLOCKINFO_BLOCK_ID, CodeWidth);
+  void EnterBlockInfoBlock() {
+    EnterSubblock(naclbitc::BLOCKINFO_BLOCK_ID);
     BlockInfoCurBID = ~0U;
   }
 private:
   /// SwitchToBlockID - If we aren't already talking about the specified block
   /// ID, emit a BLOCKINFO_CODE_SETBID record.
   void SwitchToBlockID(unsigned BlockID) {
     if (BlockInfoCurBID == BlockID) return;
     SmallVector<unsigned, 2> V;
     V.push_back(BlockID);
-    EmitRecord(bitc::BLOCKINFO_CODE_SETBID, V);
+    EmitRecord(naclbitc::BLOCKINFO_CODE_SETBID, V);
     BlockInfoCurBID = BlockID;
   }
 
   BlockInfo &getOrCreateBlockInfo(unsigned BlockID) {
     if (BlockInfo *BI = getBlockInfo(BlockID))
       return *BI;
 
     // Otherwise, add a new record.
     BlockInfoRecords.push_back(BlockInfo());
     BlockInfoRecords.back().BlockID = BlockID;
     return BlockInfoRecords.back();
   }
 
 public:
 
   /// EmitBlockInfoAbbrev - Emit a DEFINE_ABBREV record for the specified
   /// BlockID.
-  unsigned EmitBlockInfoAbbrev(unsigned BlockID, BitCodeAbbrev *Abbv) {
+  unsigned EmitBlockInfoAbbrev(unsigned BlockID, NaClBitCodeAbbrev *Abbv) {
     SwitchToBlockID(BlockID);
     EncodeAbbrev(Abbv);
 
     // Add the abbrev to the specified block record.
     BlockInfo &Info = getOrCreateBlockInfo(BlockID);
     Info.Abbrevs.push_back(Abbv);
 
-    return Info.Abbrevs.size()-1+bitc::FIRST_APPLICATION_ABBREV;
+    return Info.Abbrevs.size()-1+naclbitc::FIRST_APPLICATION_ABBREV;
   }
 };
 
 
 } // End llvm namespace
 
 #endif