Vendor import of llvm trunk r178860:

http://llvm.org/svn/llvm-project/llvm/trunk@178860

6 files changed, 268 insertions, 370 deletions

diff --git a/include/llvm/Bitcode/Archive.h b/include/llvm/Bitcode/Archive.h
index 4fd4b5d..7b30c7e 100644
--- a/include/llvm/Bitcode/Archive.h
+++ b/include/llvm/Bitcode/Archive.h
@@ -50,10 +50,10 @@ class ArchiveMember : public ilist_node<ArchiveMember> {
       SVR4SymbolTableFlag = 1,     ///< Member is a SVR4 symbol table
       BSD4SymbolTableFlag = 2,     ///< Member is a BSD4 symbol table
       LLVMSymbolTableFlag = 4,     ///< Member is an LLVM symbol table
-      BitcodeFlag = 8,             ///< Member is bitcode
-      HasPathFlag = 16,            ///< Member has a full or partial path
+      BitcodeFlag         = 8,     ///< Member is bitcode
+      HasPathFlag         = 16,    ///< Member has a full or partial path
       HasLongFilenameFlag = 32,    ///< Member uses the long filename syntax
-      StringTableFlag = 64         ///< Member is an ar(1) format string table
+      StringTableFlag     = 64     ///< Member is an ar(1) format string table
     };
 
   /// @}
diff --git a/include/llvm/Bitcode/BitCodes.h b/include/llvm/Bitcode/BitCodes.h
index 28e1ab1..b510daf 100644
--- a/include/llvm/Bitcode/BitCodes.h
+++ b/include/llvm/Bitcode/BitCodes.h
@@ -26,8 +26,8 @@
 namespace llvm {
 namespace bitc {
   enum StandardWidths {
-    BlockIDWidth = 8,  // We use VBR-8 for block IDs.
-    CodeLenWidth = 4,  // Codelen are VBR-4.
+    BlockIDWidth   = 8,  // We use VBR-8 for block IDs.
+    CodeLenWidth   = 4,  // Codelen are VBR-4.
     BlockSizeWidth = 32  // BlockSize up to 2^32 32-bit words = 16GB per block.
   };
 
@@ -69,10 +69,11 @@ namespace bitc {
   enum BlockInfoCodes {
     // DEFINE_ABBREV has magic semantics here, applying to the current SETBID'd
     // block, instead of the BlockInfo block.
-    
-    BLOCKINFO_CODE_SETBID = 1,       // SETBID: [blockid#]
-    BLOCKINFO_CODE_BLOCKNAME = 2,    // BLOCKNAME: [name]
-    BLOCKINFO_CODE_SETRECORDNAME = 3 // BLOCKINFO_CODE_SETRECORDNAME: [id, name]
+
+    BLOCKINFO_CODE_SETBID        = 1, // SETBID: [blockid#]
+    BLOCKINFO_CODE_BLOCKNAME     = 2, // BLOCKNAME: [name]
+    BLOCKINFO_CODE_SETRECORDNAME = 3  // BLOCKINFO_CODE_SETRECORDNAME:
+                                      //                             [id, name]
   };
 
 } // End bitc namespace
@@ -99,7 +100,7 @@ public:
   explicit BitCodeAbbrevOp(Encoding E, uint64_t Data = 0)
     : Val(Data), IsLiteral(false), Enc(E) {}
 
-  bool isLiteral() const { return IsLiteral; }
+  bool isLiteral() const  { return IsLiteral; }
   bool isEncoding() const { return !IsLiteral; }
 
   // Accessors for literals.
@@ -138,18 +139,18 @@ public:
     if (C >= 'a' && C <= 'z') return C-'a';
     if (C >= 'A' && C <= 'Z') return C-'A'+26;
     if (C >= '0' && C <= '9') return C-'0'+26+26;
-    if (C == '.') return 62;
-    if (C == '_') return 63;
+    if (C == '.')             return 62;
+    if (C == '_')             return 63;
     llvm_unreachable("Not a value Char6 character!");
   }
 
   static char DecodeChar6(unsigned V) {
     assert((V & ~63) == 0 && "Not a Char6 encoded character!");
-    if (V < 26) return V+'a';
-    if (V < 26+26) return V-26+'A';
+    if (V < 26)       return V+'a';
+    if (V < 26+26)    return V-26+'A';
     if (V < 26+26+10) return V-26-26+'0';
-    if (V == 62) return '.';
-    if (V == 63) return '_';
+    if (V == 62)      return '.';
+    if (V == 63)      return '_';
     llvm_unreachable("Not a value Char6 character!");
   }
 
diff --git a/include/llvm/Bitcode/BitstreamReader.h b/include/llvm/Bitcode/BitstreamReader.h
index 840f57e..f313973 100644
--- a/include/llvm/Bitcode/BitstreamReader.h
+++ b/include/llvm/Bitcode/BitstreamReader.h
@@ -12,8 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef BITSTREAM_READER_H
-#define BITSTREAM_READER_H
+#ifndef LLVM_BITCODE_BITSTREAMREADER_H
+#define LLVM_BITCODE_BITSTREAMREADER_H
 
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Bitcode/BitCodes.h"
@@ -27,6 +27,11 @@ namespace llvm {
 
   class Deserializer;
 
+/// BitstreamReader - This class is used to read from an LLVM bitcode stream,
+/// maintaining information that is global to decoding the entire file.  While
+/// a file is being read, multiple cursors can be independently advanced or
+/// skipped around within the file.  These are represented by the
+/// BitstreamCursor class.
 class BitstreamReader {
 public:
   /// BlockInfo - This contains information emitted to BLOCKINFO_BLOCK blocks.
@@ -35,12 +40,12 @@ public:
     unsigned BlockID;
     std::vector<BitCodeAbbrev*> Abbrevs;
     std::string Name;
-    
+
     std::vector<std::pair<unsigned, std::string> > RecordNames;
   };
 private:
   OwningPtr<StreamableMemoryObject> BitcodeBytes;
-  
+
   std::vector<BlockInfo> BlockInfoRecords;
 
   /// IgnoreBlockInfoNames - This is set to true if we don't care about the
@@ -86,7 +91,7 @@ public:
   /// name information.
   void CollectBlockInfoNames() { IgnoreBlockInfoNames = false; }
   bool isIgnoringBlockInfoNames() { return IgnoreBlockInfoNames; }
-  
+
   //===--------------------------------------------------------------------===//
   // Block Manipulation
   //===--------------------------------------------------------------------===//
@@ -95,7 +100,7 @@ public:
   /// block info block for this Bitstream.  We only process it for the first
   /// cursor that walks over it.
   bool hasBlockInfoRecords() const { return !BlockInfoRecords.empty(); }
-  
+
   /// getBlockInfo - If there is block info for the specified ID, return it,
   /// otherwise return null.
   const BlockInfo *getBlockInfo(unsigned BlockID) const {
@@ -119,113 +124,114 @@ public:
     BlockInfoRecords.back().BlockID = BlockID;
     return BlockInfoRecords.back();
   }
+};
+
+
+/// BitstreamEntry - When advancing through a bitstream cursor, each advance can
+/// discover a few different kinds of entries:
+///   Error    - Malformed bitcode was found.
+///   EndBlock - We've reached the end of the current block, (or the end of the
+///              file, which is treated like a series of EndBlock records.
+///   SubBlock - This is the start of a new subblock of a specific ID.
+///   Record   - This is a record with a specific AbbrevID.
+///
+struct BitstreamEntry {
+  enum {
+    Error,
+    EndBlock,
+    SubBlock,
+    Record
+  } Kind;
+
+  unsigned ID;
 
+  static BitstreamEntry getError() {
+    BitstreamEntry E; E.Kind = Error; return E;
+  }
+  static BitstreamEntry getEndBlock() {
+    BitstreamEntry E; E.Kind = EndBlock; return E;
+  }
+  static BitstreamEntry getSubBlock(unsigned ID) {
+    BitstreamEntry E; E.Kind = SubBlock; E.ID = ID; return E;
+  }
+  static BitstreamEntry getRecord(unsigned AbbrevID) {
+    BitstreamEntry E; E.Kind = Record; E.ID = AbbrevID; return E;
+  }
 };
 
+/// BitstreamCursor - This represents a position within a bitcode file.  There
+/// may be multiple independent cursors reading within one bitstream, each
+/// maintaining their own local state.
+///
+/// Unlike iterators, BitstreamCursors are heavy-weight objects that should not
+/// be passed by value.
 class BitstreamCursor {
   friend class Deserializer;
   BitstreamReader *BitStream;
   size_t NextChar;
-  
-  /// CurWord - This is the current data we have pulled from the stream but have
-  /// not returned to the client.
-  uint32_t CurWord;
-  
+
+
+  /// CurWord/word_t - This is the current data we have pulled from the stream
+  /// but have not returned to the client.  This is specifically and
+  /// intentionally defined to follow the word size of the host machine for
+  /// efficiency.  We use word_t in places that are aware of this to make it
+  /// perfectly explicit what is going on.
+  typedef uint32_t word_t;
+  word_t CurWord;
+
   /// BitsInCurWord - This is the number of bits in CurWord that are valid. This
-  /// is always from [0...31] inclusive.
+  /// is always from [0...31/63] inclusive (depending on word size).
   unsigned BitsInCurWord;
-  
+
   // CurCodeSize - This is the declared size of code values used for the current
   // block, in bits.
   unsigned CurCodeSize;
-  
+
   /// CurAbbrevs - Abbrevs installed at in this block.
   std::vector<BitCodeAbbrev*> CurAbbrevs;
-  
+
   struct Block {
     unsigned PrevCodeSize;
     std::vector<BitCodeAbbrev*> PrevAbbrevs;
     explicit Block(unsigned PCS) : PrevCodeSize(PCS) {}
   };
-  
+
   /// BlockScope - This tracks the codesize of parent blocks.
   SmallVector<Block, 8> BlockScope;
-  
+
+
 public:
   BitstreamCursor() : BitStream(0), NextChar(0) {
   }
   BitstreamCursor(const BitstreamCursor &RHS) : BitStream(0), NextChar(0) {
     operator=(RHS);
   }
-  
+
   explicit BitstreamCursor(BitstreamReader &R) : BitStream(&R) {
     NextChar = 0;
     CurWord = 0;
     BitsInCurWord = 0;
     CurCodeSize = 2;
   }
-  
+
   void init(BitstreamReader &R) {
     freeState();
-    
+
     BitStream = &R;
     NextChar = 0;
     CurWord = 0;
     BitsInCurWord = 0;
     CurCodeSize = 2;
   }
-  
+
   ~BitstreamCursor() {
     freeState();
   }
-  
-  void operator=(const BitstreamCursor &RHS) {
-    freeState();
-    
-    BitStream = RHS.BitStream;
-    NextChar = RHS.NextChar;
-    CurWord = RHS.CurWord;
-    BitsInCurWord = RHS.BitsInCurWord;
-    CurCodeSize = RHS.CurCodeSize;
-    
-    // Copy abbreviations, and bump ref counts.
-    CurAbbrevs = RHS.CurAbbrevs;
-    for (unsigned i = 0, e = static_cast<unsigned>(CurAbbrevs.size());
-         i != e; ++i)
-      CurAbbrevs[i]->addRef();
-    
-    // Copy block scope and bump ref counts.
-    BlockScope = RHS.BlockScope;
-    for (unsigned S = 0, e = static_cast<unsigned>(BlockScope.size());
-         S != e; ++S) {
-      std::vector<BitCodeAbbrev*> &Abbrevs = BlockScope[S].PrevAbbrevs;
-      for (unsigned i = 0, e = static_cast<unsigned>(Abbrevs.size());
-           i != e; ++i)
-        Abbrevs[i]->addRef();
-    }
-  }
-  
-  void freeState() {
-    // Free all the Abbrevs.
-    for (unsigned i = 0, e = static_cast<unsigned>(CurAbbrevs.size());
-         i != e; ++i)
-      CurAbbrevs[i]->dropRef();
-    CurAbbrevs.clear();
-    
-    // Free all the Abbrevs in the block scope.
-    for (unsigned S = 0, e = static_cast<unsigned>(BlockScope.size());
-         S != e; ++S) {
-      std::vector<BitCodeAbbrev*> &Abbrevs = BlockScope[S].PrevAbbrevs;
-      for (unsigned i = 0, e = static_cast<unsigned>(Abbrevs.size());
-           i != e; ++i)
-        Abbrevs[i]->dropRef();
-    }
-    BlockScope.clear();
-  }
-  
-  /// GetAbbrevIDWidth - Return the number of bits used to encode an abbrev #.
-  unsigned GetAbbrevIDWidth() const { return CurCodeSize; }
-  
+
+  void operator=(const BitstreamCursor &RHS);
+
+  void freeState();
+
   bool isEndPos(size_t pos) {
     return BitStream->getBitcodeBytes().isObjectEnd(static_cast<uint64_t>(pos));
   }
@@ -236,61 +242,113 @@ public:
         static_cast<uint64_t>(pos - 1));
   }
 
-  unsigned char getByte(size_t pos) {
-    uint8_t byte = -1;
-    BitStream->getBitcodeBytes().readByte(pos, &byte);
-    return byte;
-  }
-
   uint32_t getWord(size_t pos) {
-    uint8_t buf[sizeof(uint32_t)];
-    memset(buf, 0xFF, sizeof(buf));
-    BitStream->getBitcodeBytes().readBytes(pos,
-                                           sizeof(buf),
-                                           buf,
-                                           NULL);
+    uint8_t buf[4] = { 0xFF, 0xFF, 0xFF, 0xFF };
+    BitStream->getBitcodeBytes().readBytes(pos, sizeof(buf), buf, NULL);
     return *reinterpret_cast<support::ulittle32_t *>(buf);
   }
 
   bool AtEndOfStream() {
-    return isEndPos(NextChar) && BitsInCurWord == 0;
+    return BitsInCurWord == 0 && isEndPos(NextChar);
   }
-  
+
+  /// getAbbrevIDWidth - Return the number of bits used to encode an abbrev #.
+  unsigned getAbbrevIDWidth() const { return CurCodeSize; }
+
   /// GetCurrentBitNo - Return the bit # of the bit we are reading.
   uint64_t GetCurrentBitNo() const {
     return NextChar*CHAR_BIT - BitsInCurWord;
   }
-  
+
   BitstreamReader *getBitStreamReader() {
     return BitStream;
   }
   const BitstreamReader *getBitStreamReader() const {
     return BitStream;
   }
-  
-  
+
+  /// Flags that modify the behavior of advance().
+  enum {
+    /// AF_DontPopBlockAtEnd - If this flag is used, the advance() method does
+    /// not automatically pop the block scope when the end of a block is
+    /// reached.
+    AF_DontPopBlockAtEnd = 1,
+
+    /// AF_DontAutoprocessAbbrevs - If this flag is used, abbrev entries are
+    /// returned just like normal records.
+    AF_DontAutoprocessAbbrevs = 2
+  };
+
+  /// advance - Advance the current bitstream, returning the next entry in the
+  /// stream.
+  BitstreamEntry advance(unsigned Flags = 0) {
+    while (1) {
+      unsigned Code = ReadCode();
+      if (Code == bitc::END_BLOCK) {
+        // Pop the end of the block unless Flags tells us not to.
+        if (!(Flags & AF_DontPopBlockAtEnd) && ReadBlockEnd())
+          return BitstreamEntry::getError();
+        return BitstreamEntry::getEndBlock();
+      }
+
+      if (Code == bitc::ENTER_SUBBLOCK)
+        return BitstreamEntry::getSubBlock(ReadSubBlockID());
+
+      if (Code == bitc::DEFINE_ABBREV &&
+          !(Flags & AF_DontAutoprocessAbbrevs)) {
+        // We read and accumulate abbrev's, the client can't do anything with
+        // them anyway.
+        ReadAbbrevRecord();
+        continue;
+      }
+
+      return BitstreamEntry::getRecord(Code);
+    }
+  }
+
+  /// advanceSkippingSubblocks - This is a convenience function for clients that
+  /// don't expect any subblocks.  This just skips over them automatically.
+  BitstreamEntry advanceSkippingSubblocks(unsigned Flags = 0) {
+    while (1) {
+      // If we found a normal entry, return it.
+      BitstreamEntry Entry = advance(Flags);
+      if (Entry.Kind != BitstreamEntry::SubBlock)
+        return Entry;
+
+      // If we found a sub-block, just skip over it and check the next entry.
+      if (SkipBlock())
+        return BitstreamEntry::getError();
+    }
+  }
+
   /// JumpToBit - Reset the stream to the specified bit number.
   void JumpToBit(uint64_t BitNo) {
-    uintptr_t ByteNo = uintptr_t(BitNo/8) & ~3;
-    uintptr_t WordBitNo = uintptr_t(BitNo) & 31;
+    uintptr_t ByteNo = uintptr_t(BitNo/8) & ~(sizeof(word_t)-1);
+    unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1));
     assert(canSkipToPos(ByteNo) && "Invalid location");
-    
+
     // Move the cursor to the right word.
     NextChar = ByteNo;
     BitsInCurWord = 0;
     CurWord = 0;
-    
+
     // Skip over any bits that are already consumed.
-    if (WordBitNo)
-      Read(static_cast<unsigned>(WordBitNo));
+    if (WordBitNo) {
+      if (sizeof(word_t) > 4)
+        Read64(WordBitNo);
+      else
+        Read(WordBitNo);
+    }
   }
-  
-  
+
+
   uint32_t Read(unsigned NumBits) {
-    assert(NumBits <= 32 && "Cannot return more than 32 bits!");
+    assert(NumBits && NumBits <= 32 &&
+           "Cannot return zero or more than 32 bits!");
+
     // If the field is fully contained by CurWord, return it quickly.
     if (BitsInCurWord >= NumBits) {
-      uint32_t R = CurWord & ((1U << NumBits)-1);
+      uint32_t R = uint32_t(CurWord) & (~0U >> (32-NumBits));
       CurWord >>= NumBits;
       BitsInCurWord -= NumBits;
       return R;
@@ -303,24 +361,37 @@ public:
       return 0;
     }
 
-    unsigned R = CurWord;
+    uint32_t R = uint32_t(CurWord);
 
     // Read the next word from the stream.
-    CurWord = getWord(NextChar);
-    NextChar += 4;
+    uint8_t Array[sizeof(word_t)] = {0};
+
+    BitStream->getBitcodeBytes().readBytes(NextChar, sizeof(Array),
+                                           Array, NULL);
+
+    // Handle big-endian byte-swapping if necessary.
+    support::detail::packed_endian_specific_integral
+      <word_t, support::little, support::unaligned> EndianValue;
+    memcpy(&EndianValue, Array, sizeof(Array));
+
+    CurWord = EndianValue;
+
+    NextChar += sizeof(word_t);
 
     // Extract NumBits-BitsInCurWord from what we just read.
     unsigned BitsLeft = NumBits-BitsInCurWord;
 
-    // Be careful here, BitsLeft is in the range [1..32] inclusive.
-    R |= (CurWord & (~0U >> (32-BitsLeft))) << BitsInCurWord;
+    // Be careful here, BitsLeft is in the range [1..32]/[1..64] inclusive.
+    R |= uint32_t((CurWord & (word_t(~0ULL) >> (sizeof(word_t)*8-BitsLeft)))
+                    << BitsInCurWord);
 
-    // BitsLeft bits have just been used up from CurWord.
-    if (BitsLeft != 32)
+    // BitsLeft bits have just been used up from CurWord.  BitsLeft is in the
+    // range [1..32]/[1..64] so be careful how we shift.
+    if (BitsLeft != sizeof(word_t)*8)
       CurWord >>= BitsLeft;
     else
       CurWord = 0;
-    BitsInCurWord = 32-BitsLeft;
+    BitsInCurWord = sizeof(word_t)*8-BitsLeft;
     return R;
   }
 
@@ -369,10 +440,21 @@ public:
     }
   }
 
-  void SkipToWord() {
+private:
+  void SkipToFourByteBoundary() {
+    // If word_t is 64-bits and if we've read less than 32 bits, just dump
+    // the bits we have up to the next 32-bit boundary.
+    if (sizeof(word_t) > 4 &&
+        BitsInCurWord >= 32) {
+      CurWord >>= BitsInCurWord-32;
+      BitsInCurWord = 32;
+      return;
+    }
+
     BitsInCurWord = 0;
     CurWord = 0;
   }
+public:
 
   unsigned ReadCode() {
     return Read(CurCodeSize);
@@ -395,62 +477,37 @@ public:
     // Read and ignore the codelen value.  Since we are skipping this block, we
     // don't care what code widths are used inside of it.
     ReadVBR(bitc::CodeLenWidth);
-    SkipToWord();
-    unsigned NumWords = Read(bitc::BlockSizeWidth);
+    SkipToFourByteBoundary();
+    unsigned NumFourBytes = Read(bitc::BlockSizeWidth);
 
     // Check that the block wasn't partially defined, and that the offset isn't
     // bogus.
-    size_t SkipTo = NextChar + NumWords*4;
-    if (AtEndOfStream() || !canSkipToPos(SkipTo))
+    size_t SkipTo = GetCurrentBitNo() + NumFourBytes*4*8;
+    if (AtEndOfStream() || !canSkipToPos(SkipTo/8))
       return true;
 
-    NextChar = SkipTo;
+    JumpToBit(SkipTo);
     return false;
   }
 
   /// EnterSubBlock - Having read the ENTER_SUBBLOCK abbrevid, enter
   /// the block, and return true if the block has an error.
-  bool EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = 0) {
-    // Save the current block's state on BlockScope.
-    BlockScope.push_back(Block(CurCodeSize));
-    BlockScope.back().PrevAbbrevs.swap(CurAbbrevs);
-
-    // Add the abbrevs specific to this block to the CurAbbrevs list.
-    if (const BitstreamReader::BlockInfo *Info =
-          BitStream->getBlockInfo(BlockID)) {
-      for (unsigned i = 0, e = static_cast<unsigned>(Info->Abbrevs.size());
-           i != e; ++i) {
-        CurAbbrevs.push_back(Info->Abbrevs[i]);
-        CurAbbrevs.back()->addRef();
-      }
-    }
-
-    // Get the codesize of this block.
-    CurCodeSize = ReadVBR(bitc::CodeLenWidth);
-    SkipToWord();
-    unsigned NumWords = Read(bitc::BlockSizeWidth);
-    if (NumWordsP) *NumWordsP = NumWords;
-
-    // Validate that this block is sane.
-    if (CurCodeSize == 0 || AtEndOfStream())
-      return true;
-
-    return false;
-  }
+  bool EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = 0);
 
   bool ReadBlockEnd() {
     if (BlockScope.empty()) return true;
 
     // Block tail:
     //    [END_BLOCK, <align4bytes>]
-    SkipToWord();
+    SkipToFourByteBoundary();
 
-    PopBlockScope();
+    popBlockScope();
     return false;
   }
 
 private:
-  void PopBlockScope() {
+
+  void popBlockScope() {
     CurCodeSize = BlockScope.back().PrevCodeSize;
 
     // Delete abbrevs from popped scope.
@@ -462,207 +519,40 @@ private:
     BlockScope.pop_back();
   }
 
- //===--------------------------------------------------------------------===//
+  //===--------------------------------------------------------------------===//
   // Record Processing
   //===--------------------------------------------------------------------===//
 
 private:
-  void ReadAbbreviatedLiteral(const BitCodeAbbrevOp &Op,
-                              SmallVectorImpl<uint64_t> &Vals) {
-    assert(Op.isLiteral() && "Not a literal");
-    // If the abbrev specifies the literal value to use, use it.
-    Vals.push_back(Op.getLiteralValue());
-  }
-  
-  void ReadAbbreviatedField(const BitCodeAbbrevOp &Op,
-                            SmallVectorImpl<uint64_t> &Vals) {
-    assert(!Op.isLiteral() && "Use ReadAbbreviatedLiteral for literals!");
-
-    // Decode the value as we are commanded.
-    switch (Op.getEncoding()) {
-    default: llvm_unreachable("Unknown encoding!");
-    case BitCodeAbbrevOp::Fixed:
-      Vals.push_back(Read((unsigned)Op.getEncodingData()));
-      break;
-    case BitCodeAbbrevOp::VBR:
-      Vals.push_back(ReadVBR64((unsigned)Op.getEncodingData()));
-      break;
-    case BitCodeAbbrevOp::Char6:
-      Vals.push_back(BitCodeAbbrevOp::DecodeChar6(Read(6)));
-      break;
-    }
-  }
+  void readAbbreviatedLiteral(const BitCodeAbbrevOp &Op,
+                              SmallVectorImpl<uint64_t> &Vals);
+  void readAbbreviatedField(const BitCodeAbbrevOp &Op,
+                            SmallVectorImpl<uint64_t> &Vals);
+  void skipAbbreviatedField(const BitCodeAbbrevOp &Op);
+
 public:
 
-  /// getAbbrev - Return the abbreviation for the specified AbbrevId. 
+  /// getAbbrev - Return the abbreviation for the specified AbbrevId.
   const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) {
     unsigned AbbrevNo = AbbrevID-bitc::FIRST_APPLICATION_ABBREV;
     assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
     return CurAbbrevs[AbbrevNo];
   }
-  
-  unsigned ReadRecord(unsigned AbbrevID, SmallVectorImpl<uint64_t> &Vals,
-                      const char **BlobStart = 0, unsigned *BlobLen = 0) {
-    if (AbbrevID == bitc::UNABBREV_RECORD) {
-      unsigned Code = ReadVBR(6);
-      unsigned NumElts = ReadVBR(6);
-      for (unsigned i = 0; i != NumElts; ++i)
-        Vals.push_back(ReadVBR64(6));
-      return Code;
-    }
 
-    const BitCodeAbbrev *Abbv = getAbbrev(AbbrevID);
-
-    for (unsigned i = 0, e = Abbv->getNumOperandInfos(); i != e; ++i) {
-      const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
-      if (Op.isLiteral()) {
-        ReadAbbreviatedLiteral(Op, Vals); 
-      } else if (Op.getEncoding() == BitCodeAbbrevOp::Array) {
-        // Array case.  Read the number of elements as a vbr6.
-        unsigned NumElts = ReadVBR(6);
-
-        // Get the element encoding.
-        assert(i+2 == e && "array op not second to last?");
-        const BitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
-
-        // Read all the elements.
-        for (; NumElts; --NumElts)
-          ReadAbbreviatedField(EltEnc, Vals);
-      } else if (Op.getEncoding() == BitCodeAbbrevOp::Blob) {
-        // Blob case.  Read the number of bytes as a vbr6.
-        unsigned NumElts = ReadVBR(6);
-        SkipToWord();  // 32-bit alignment
-
-        // Figure out where the end of this blob will be including tail padding.
-        size_t NewEnd = NextChar+((NumElts+3)&~3);
-        
-        // If this would read off the end of the bitcode file, just set the
-        // record to empty and return.
-        if (!canSkipToPos(NewEnd)) {
-          Vals.append(NumElts, 0);
-          NextChar = BitStream->getBitcodeBytes().getExtent();
-          break;
-        }
-        
-        // Otherwise, read the number of bytes.  If we can return a reference to
-        // the data, do so to avoid copying it.
-        if (BlobStart) {
-          *BlobStart = (const char*)BitStream->getBitcodeBytes().getPointer(
-              NextChar, NumElts);
-          *BlobLen = NumElts;
-        } else {
-          for (; NumElts; ++NextChar, --NumElts)
-            Vals.push_back(getByte(NextChar));
-        }
-        // Skip over tail padding.
-        NextChar = NewEnd;
-      } else {
-        ReadAbbreviatedField(Op, Vals);
-      }
-    }
-
-    unsigned Code = (unsigned)Vals[0];
-    Vals.erase(Vals.begin());
-    return Code;
-  }
+  /// skipRecord - Read the current record and discard it.
+  void skipRecord(unsigned AbbrevID);
 
-  unsigned ReadRecord(unsigned AbbrevID, SmallVectorImpl<uint64_t> &Vals,
-                      const char *&BlobStart, unsigned &BlobLen) {
-    return ReadRecord(AbbrevID, Vals, &BlobStart, &BlobLen);
-  }
+  unsigned readRecord(unsigned AbbrevID, SmallVectorImpl<uint64_t> &Vals,
+                      StringRef *Blob = 0);
 
-  
   //===--------------------------------------------------------------------===//
   // Abbrev Processing
   //===--------------------------------------------------------------------===//
+  void ReadAbbrevRecord();
 
-  void ReadAbbrevRecord() {
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    unsigned NumOpInfo = ReadVBR(5);
-    for (unsigned i = 0; i != NumOpInfo; ++i) {
-      bool IsLiteral = Read(1) ? true : false;
-      if (IsLiteral) {
-        Abbv->Add(BitCodeAbbrevOp(ReadVBR64(8)));
-        continue;
-      }
-
-      BitCodeAbbrevOp::Encoding E = (BitCodeAbbrevOp::Encoding)Read(3);
-      if (BitCodeAbbrevOp::hasEncodingData(E))
-        Abbv->Add(BitCodeAbbrevOp(E, ReadVBR64(5)));
-      else
-        Abbv->Add(BitCodeAbbrevOp(E));
-    }
-    CurAbbrevs.push_back(Abbv);
-  }
-  
-public:
-
-  bool ReadBlockInfoBlock() {
-    // If this is the second stream to get to the block info block, skip it.
-    if (BitStream->hasBlockInfoRecords())
-      return SkipBlock();
-    
-    if (EnterSubBlock(bitc::BLOCKINFO_BLOCK_ID)) return true;
-
-    SmallVector<uint64_t, 64> Record;
-    BitstreamReader::BlockInfo *CurBlockInfo = 0;
-
-    // Read all the records for this module.
-    while (1) {
-      unsigned Code = ReadCode();
-      if (Code == bitc::END_BLOCK)
-        return ReadBlockEnd();
-      if (Code == bitc::ENTER_SUBBLOCK) {
-        ReadSubBlockID();
-        if (SkipBlock()) return true;
-        continue;
-      }
-
-      // Read abbrev records, associate them with CurBID.
-      if (Code == bitc::DEFINE_ABBREV) {
-        if (!CurBlockInfo) return true;
-        ReadAbbrevRecord();
-
-        // ReadAbbrevRecord installs the abbrev in CurAbbrevs.  Move it to the
-        // appropriate BlockInfo.
-        BitCodeAbbrev *Abbv = CurAbbrevs.back();
-        CurAbbrevs.pop_back();
-        CurBlockInfo->Abbrevs.push_back(Abbv);
-        continue;
-      }
-
-      // Read a record.
-      Record.clear();
-      switch (ReadRecord(Code, Record)) {
-      default: break;  // Default behavior, ignore unknown content.
-      case bitc::BLOCKINFO_CODE_SETBID:
-        if (Record.size() < 1) return true;
-        CurBlockInfo = &BitStream->getOrCreateBlockInfo((unsigned)Record[0]);
-        break;
-      case bitc::BLOCKINFO_CODE_BLOCKNAME: {
-        if (!CurBlockInfo) return true;
-        if (BitStream->isIgnoringBlockInfoNames()) break;  // Ignore name.
-        std::string Name;
-        for (unsigned i = 0, e = Record.size(); i != e; ++i)
-          Name += (char)Record[i];
-        CurBlockInfo->Name = Name;
-        break;
-      }
-      case bitc::BLOCKINFO_CODE_SETRECORDNAME: {
-        if (!CurBlockInfo) return true;
-        if (BitStream->isIgnoringBlockInfoNames()) break;  // Ignore name.
-        std::string Name;
-        for (unsigned i = 1, e = Record.size(); i != e; ++i)
-          Name += (char)Record[i];
-        CurBlockInfo->RecordNames.push_back(std::make_pair((unsigned)Record[0],
-                                                           Name));
-        break;
-      }
-      }
-    }
-  }
+  bool ReadBlockInfoBlock();
 };
-  
+
 } // End llvm namespace
 
 #endif
diff --git a/include/llvm/Bitcode/BitstreamWriter.h b/include/llvm/Bitcode/BitstreamWriter.h
index dea118f..a837211 100644
--- a/include/llvm/Bitcode/BitstreamWriter.h
+++ b/include/llvm/Bitcode/BitstreamWriter.h
@@ -12,11 +12,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef BITSTREAM_WRITER_H
-#define BITSTREAM_WRITER_H
+#ifndef LLVM_BITCODE_BITSTREAMWRITER_H
+#define LLVM_BITCODE_BITSTREAMWRITER_H
 
-#include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Bitcode/BitCodes.h"
 #include <vector>
 
@@ -273,7 +273,7 @@ public:
 
 private:
   /// EmitAbbreviatedLiteral - Emit a literal value according to its abbrev
-  /// record.  This is a no-op, since the abbrev specifies the literal to use. 
+  /// 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");
@@ -282,13 +282,13 @@ private:
     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.
     switch (Op.getEncoding()) {
     default: llvm_unreachable("Unknown encoding!");
@@ -305,7 +305,7 @@ private:
       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
@@ -341,11 +341,11 @@ private:
                  "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 = 0;
         } else {
@@ -359,7 +359,7 @@ private:
       } else if (Op.getEncoding() == BitCodeAbbrevOp::Blob) {
         // If this record has blob data, emit it, otherwise we must have record
         // entries to encode this way.
-        
+
         // Emit a vbr6 to indicate the number of elements present.
         if (BlobData) {
           EmitVBR(static_cast<uint32_t>(BlobLen), 6);
@@ -368,7 +368,7 @@ private:
         } else {
           EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
         }
-        
+
         // Flush to a 32-bit alignment boundary.
         FlushToWord();
 
@@ -376,7 +376,7 @@ private:
         if (BlobData) {
           for (unsigned i = 0; i != BlobLen; ++i)
             WriteByte((unsigned char)BlobData[i]);
-          
+
           // Know that blob data is consumed for assertion below.
           BlobData = 0;
         } else {
@@ -399,7 +399,7 @@ private:
     assert(BlobData == 0 &&
            "Blob data specified for record that doesn't use it!");
   }
-  
+
 public:
 
   /// EmitRecord - Emit the specified record to the stream, using an abbrev if
@@ -420,10 +420,10 @@ public:
 
     // 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.
@@ -431,7 +431,7 @@ public:
   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
@@ -458,10 +458,10 @@ public:
   template<typename uintty>
   void EmitRecordWithArray(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
                           const char *ArrayData, unsigned ArrayLen) {
-    return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(ArrayData, 
+    return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(ArrayData,
                                                             ArrayLen));
   }
-  
+
   //===--------------------------------------------------------------------===//
   // Abbrev Emission
   //===--------------------------------------------------------------------===//
diff --git a/include/llvm/Bitcode/LLVMBitCodes.h b/include/llvm/Bitcode/LLVMBitCodes.h
index c1dc190..f9690d5 100644
--- a/include/llvm/Bitcode/LLVMBitCodes.h
+++ b/include/llvm/Bitcode/LLVMBitCodes.h
@@ -29,18 +29,17 @@ namespace bitc {
 
     // Module sub-block id's.
     PARAMATTR_BLOCK_ID,
+    PARAMATTR_GROUP_BLOCK_ID,
 
-    UNUSED_ID1,
-    
     CONSTANTS_BLOCK_ID,
     FUNCTION_BLOCK_ID,
-    
-    UNUSED_ID2,
-    
+
+    UNUSED_ID1,
+
     VALUE_SYMTAB_BLOCK_ID,
     METADATA_BLOCK_ID,
     METADATA_ATTACHMENT_ID,
-    
+
     TYPE_BLOCK_ID_NEW,
 
     USELIST_BLOCK_ID
@@ -54,6 +53,8 @@ namespace bitc {
     MODULE_CODE_DATALAYOUT  = 3,    // DATALAYOUT:  [strchr x N]
     MODULE_CODE_ASM         = 4,    // ASM:         [strchr x N]
     MODULE_CODE_SECTIONNAME = 5,    // SECTIONNAME: [strchr x N]
+
+    // FIXME: Remove DEPLIB in 4.0.
     MODULE_CODE_DEPLIB      = 6,    // DEPLIB:      [strchr x N]
 
     // GLOBALVAR: [pointer type, isconst, initid,
@@ -67,7 +68,7 @@ namespace bitc {
     // ALIAS: [alias type, aliasee val#, linkage, visibility]
     MODULE_CODE_ALIAS       = 9,
 
-    /// MODULE_CODE_PURGEVALS: [numvals]
+    // MODULE_CODE_PURGEVALS: [numvals]
     MODULE_CODE_PURGEVALS   = 10,
 
     MODULE_CODE_GCNAME      = 11   // GCNAME: [strchr x N]
@@ -75,7 +76,12 @@ namespace bitc {
 
   /// PARAMATTR blocks have code for defining a parameter attribute set.
   enum AttributeCodes {
-    PARAMATTR_CODE_ENTRY = 1   // ENTRY: [paramidx0, attr0, paramidx1, attr1...]
+    // FIXME: Remove `PARAMATTR_CODE_ENTRY_OLD' in 4.0
+    PARAMATTR_CODE_ENTRY_OLD  = 1, // ENTRY: [paramidx0, attr0,
+                                   //         paramidx1, attr1...]
+    PARAMATTR_CODE_ENTRY      = 2, // ENTRY: [paramidx0, attrgrp0,
+                                   //         paramidx1, attrgrp1, ...]
+    PARAMATTR_GRP_CODE_ENTRY  = 3  // ENTRY: [id, attr0, att1, ...]
   };
 
   /// TYPE blocks have codes for each type primitive they use.
@@ -93,9 +99,9 @@ namespace bitc {
 
     TYPE_CODE_FUNCTION_OLD = 9, // FUNCTION: [vararg, attrid, retty,
                                 //            paramty x N]
-    
+
     TYPE_CODE_HALF     =  10,   // HALF
-    
+
     TYPE_CODE_ARRAY    = 11,    // ARRAY: [numelts, eltty]
     TYPE_CODE_VECTOR   = 12,    // VECTOR: [numelts, eltty]
 
@@ -109,7 +115,7 @@ namespace bitc {
     TYPE_CODE_METADATA = 16,    // METADATA
 
     TYPE_CODE_X86_MMX = 17,     // X86 MMX
-    
+
     TYPE_CODE_STRUCT_ANON = 18, // STRUCT_ANON: [ispacked, eltty x N]
     TYPE_CODE_STRUCT_NAME = 19, // STRUCT_NAME: [strchr x N]
     TYPE_CODE_STRUCT_NAMED = 20,// STRUCT_NAMED: [ispacked, eltty x N]
@@ -141,6 +147,7 @@ namespace bitc {
     METADATA_NAMED_NODE    = 10,  // NAMED_NODE:    [n x mdnodes]
     METADATA_ATTACHMENT    = 11   // [m x [value, [n x [id, mdnode]]]
   };
+
   // The constants block (CONSTANTS_BLOCK_ID) describes emission for each
   // constant and maintains an implicit current type value.
   enum ConstantsCodes {
@@ -234,7 +241,7 @@ namespace bitc {
     OBO_NO_SIGNED_WRAP = 1
   };
 
-  /// PossiblyExactOperatorOptionalFlags - Flags for serializing 
+  /// PossiblyExactOperatorOptionalFlags - Flags for serializing
   /// PossiblyExactOperator's SubclassOptionalData contents.
   enum PossiblyExactOperatorOptionalFlags {
     PEO_EXACT = 0
diff --git a/include/llvm/Bitcode/ReaderWriter.h b/include/llvm/Bitcode/ReaderWriter.h
index dd96b04..78f40ca 100644
--- a/include/llvm/Bitcode/ReaderWriter.h
+++ b/include/llvm/Bitcode/ReaderWriter.h
@@ -11,8 +11,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_BITCODE_H
-#define LLVM_BITCODE_H
+#ifndef LLVM_BITCODE_READERWRITER_H
+#define LLVM_BITCODE_READERWRITER_H
 
 #include <string>