C++ GCOVBuffer::readArcTag方法代码示例

/// readGCDA - Read a function from the GCDA buffer. Return false if an error
/// occurs.
bool GCOVFunction::readGCDA(GCOVBuffer &Buff, GCOV::GCOVVersion Version) {
  uint32_t Dummy;
  if (!Buff.readInt(Dummy)) return false; // Function header length

  uint32_t GCDAIdent;
  if (!Buff.readInt(GCDAIdent)) return false;
  if (Ident != GCDAIdent) {
    errs() << "Function identifiers do not match: " << Ident << " != "
           << GCDAIdent << " (in " << Name << ").\n";
    return false;
  }

  uint32_t GCDAChecksum;
  if (!Buff.readInt(GCDAChecksum)) return false;
  if (Checksum != GCDAChecksum) {
    errs() << "Function checksums do not match: " << Checksum << " != "
           << GCDAChecksum << " (in " << Name << ").\n";
    return false;
  }

  uint32_t CfgChecksum;
  if (Version != GCOV::V402) {
    if (!Buff.readInt(CfgChecksum)) return false;
    if (Parent.getChecksum() != CfgChecksum) {
      errs() << "File checksums do not match: " << Parent.getChecksum()
             << " != " << CfgChecksum << " (in " << Name << ").\n";
      return false;
    }
  }

  StringRef GCDAName;
  if (!Buff.readString(GCDAName)) return false;
  if (Name != GCDAName) {
    errs() << "Function names do not match: " << Name << " != " << GCDAName
           << ".\n";
    return false;
  }

  if (!Buff.readArcTag()) {
    errs() << "Arc tag not found (in " << Name << ").\n";
    return false;
  }

  uint32_t Count;
  if (!Buff.readInt(Count)) return false;
  Count /= 2;

  // This for loop adds the counts for each block. A second nested loop is
  // required to combine the edge counts that are contained in the GCDA file.
  for (uint32_t BlockNo = 0; Count > 0; ++BlockNo) {
    // The last block is always reserved for exit block
    if (BlockNo >= Blocks.size()-1) {
      errs() << "Unexpected number of edges (in " << Name << ").\n";
      return false;
    }
    GCOVBlock &Block = *Blocks[BlockNo];
    for (size_t EdgeNo = 0, End = Block.getNumDstEdges(); EdgeNo < End;
           ++EdgeNo) {
      if (Count == 0) {
        errs() << "Unexpected number of edges (in " << Name << ").\n";
        return false;
      }
      uint64_t ArcCount;
      if (!Buff.readInt64(ArcCount)) return false;
      Block.addCount(EdgeNo, ArcCount);
      --Count;
    }
  }
  return true;
}

/// read - Read a aunction from the buffer. Return false if buffer cursor
/// does not point to a function tag.
bool GCOVFunction::read(GCOVBuffer &Buff, GCOV::GCOVFormat Format) {
  if (!Buff.readFunctionTag())
    return false;

  Buff.readInt(); // Function header length
  Ident = Buff.readInt(); 
  Buff.readInt(); // Checksum #1
  if (Format != GCOV::GCNO_402)
    Buff.readInt(); // Checksum #2

  Name = Buff.readString();
  if (Format == GCOV::GCNO_402 || Format == GCOV::GCNO_404)
    Filename = Buff.readString();

  if (Format == GCOV::GCDA_402 || Format == GCOV::GCDA_404) {
    Buff.readArcTag();
    uint32_t Count = Buff.readInt() / 2;
    for (unsigned i = 0, e = Count; i != e; ++i) {
      Blocks[i]->addCount(Buff.readInt64());
    }
    return true;
  }

  LineNumber = Buff.readInt();

  // read blocks.
  bool BlockTagFound = Buff.readBlockTag();
  (void)BlockTagFound;
  assert(BlockTagFound && "Block Tag not found!");
  uint32_t BlockCount = Buff.readInt();
  for (int i = 0, e = BlockCount; i != e; ++i) {
    Buff.readInt(); // Block flags;
    Blocks.push_back(new GCOVBlock(i));
  }

  // read edges.
  while (Buff.readEdgeTag()) {
    uint32_t EdgeCount = (Buff.readInt() - 1) / 2;
    uint32_t BlockNo = Buff.readInt();
    assert(BlockNo < BlockCount && "Unexpected Block number!");
    for (int i = 0, e = EdgeCount; i != e; ++i) {
      Blocks[BlockNo]->addEdge(Buff.readInt());
      Buff.readInt(); // Edge flag
    }
  }

  // read line table.
  while (Buff.readLineTag()) {
    uint32_t LineTableLength = Buff.readInt();
    uint32_t Size = Buff.getCursor() + LineTableLength*4;
    uint32_t BlockNo = Buff.readInt();
    assert(BlockNo < BlockCount && "Unexpected Block number!");
    GCOVBlock *Block = Blocks[BlockNo];
    Buff.readInt(); // flag
    while (Buff.getCursor() != (Size - 4)) {
      StringRef Filename = Buff.readString();
      if (Buff.getCursor() == (Size - 4)) break;
      while (uint32_t L = Buff.readInt())
        Block->addLine(Filename, L);
    }
    Buff.readInt(); // flag
  }
  return true;
}