C++ DWARFDataExtractor::getRelocatedAddress方法代码示例

bool DWARFDebugRangeList::extract(const DWARFDataExtractor &data,
                                  uint32_t *offset_ptr) {
  clear();
  if (!data.isValidOffset(*offset_ptr))
    return false;
  AddressSize = data.getAddressSize();
  if (AddressSize != 4 && AddressSize != 8)
    return false;
  Offset = *offset_ptr;
  while (true) {
    RangeListEntry entry;
    uint32_t prev_offset = *offset_ptr;
    entry.StartAddress =
        data.getRelocatedAddress(offset_ptr, &entry.SectionIndex);
    entry.EndAddress = data.getRelocatedAddress(offset_ptr);

    // Check that both values were extracted correctly.
    if (*offset_ptr != prev_offset + 2 * AddressSize) {
      clear();
      return false;
    }
    if (entry.isEndOfListEntry())
      break;
    Entries.push_back(entry);
  }
  return true;
}

Error DWARFDebugRangeList::extract(const DWARFDataExtractor &data,
                                   uint32_t *offset_ptr) {
  clear();
  if (!data.isValidOffset(*offset_ptr))
    return createStringError(errc::invalid_argument,
                       "invalid range list offset 0x%" PRIx32, *offset_ptr);

  AddressSize = data.getAddressSize();
  if (AddressSize != 4 && AddressSize != 8)
    return createStringError(errc::invalid_argument,
                       "invalid address size: %" PRIu8, AddressSize);
  Offset = *offset_ptr;
  while (true) {
    RangeListEntry Entry;
    Entry.SectionIndex = -1ULL;

    uint32_t prev_offset = *offset_ptr;
    Entry.StartAddress = data.getRelocatedAddress(offset_ptr);
    Entry.EndAddress =
        data.getRelocatedAddress(offset_ptr, &Entry.SectionIndex);

    // Check that both values were extracted correctly.
    if (*offset_ptr != prev_offset + 2 * AddressSize) {
      clear();
      return createStringError(errc::invalid_argument,
                         "invalid range list entry at offset 0x%" PRIx32,
                         prev_offset);
    }
    if (Entry.isEndOfListEntry())
      break;
    Entries.push_back(Entry);
  }
  return Error::success();
}

Optional<DWARFDebugLoc::LocationList>
DWARFDebugLoc::parseOneLocationList(DWARFDataExtractor Data, unsigned *Offset) {
  LocationList LL;
  LL.Offset = *Offset;

  // 2.6.2 Location Lists
  // A location list entry consists of:
  while (true) {
    Entry E;
    if (!Data.isValidOffsetForDataOfSize(*Offset, 2 * Data.getAddressSize())) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }

    // 1. A beginning address offset. ...
    E.Begin = Data.getRelocatedAddress(Offset);

    // 2. An ending address offset. ...
    E.End = Data.getRelocatedAddress(Offset);

    // The end of any given location list is marked by an end of list entry,
    // which consists of a 0 for the beginning address offset and a 0 for the
    // ending address offset.
    if (E.Begin == 0 && E.End == 0)
      return LL;

    if (!Data.isValidOffsetForDataOfSize(*Offset, 2)) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }

    unsigned Bytes = Data.getU16(Offset);
    if (!Data.isValidOffsetForDataOfSize(*Offset, Bytes)) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }
    // A single location description describing the location of the object...
    StringRef str = Data.getData().substr(*Offset, Bytes);
    *Offset += Bytes;
    E.Loc.reserve(str.size());
    std::copy(str.begin(), str.end(), std::back_inserter(E.Loc));
    LL.Entries.push_back(std::move(E));
  }
}

bool DWARFDebugLine::LineTable::parse(DWARFDataExtractor &DebugLineData,
                                      uint32_t *OffsetPtr, const DWARFUnit *U,
                                      raw_ostream *OS) {
  const uint32_t DebugLineOffset = *OffsetPtr;

  clear();

  if (!Prologue.parse(DebugLineData, OffsetPtr, U)) {
    // Restore our offset and return false to indicate failure!
    *OffsetPtr = DebugLineOffset;
    return false;
  }

  if (OS)
    Prologue.dump(*OS);

  const uint32_t EndOffset =
      DebugLineOffset + Prologue.TotalLength + Prologue.sizeofTotalLength();

  // See if we should tell the data extractor the address size.
  if (DebugLineData.getAddressSize() == 0)
    DebugLineData.setAddressSize(Prologue.getAddressSize());
  else
    assert(Prologue.getAddressSize() == 0 ||
           Prologue.getAddressSize() == DebugLineData.getAddressSize());

  ParsingState State(this);

  while (*OffsetPtr < EndOffset) {
    if (OS)
      *OS << format("0x%08.08" PRIx32 ": ", *OffsetPtr);

    uint8_t Opcode = DebugLineData.getU8(OffsetPtr);

    if (OS)
      *OS << format("%02.02" PRIx8 " ", Opcode);

    if (Opcode == 0) {
      // Extended Opcodes always start with a zero opcode followed by
      // a uleb128 length so you can skip ones you don't know about
      uint64_t Len = DebugLineData.getULEB128(OffsetPtr);
      uint32_t ExtOffset = *OffsetPtr;

      // Tolerate zero-length; assume length is correct and soldier on.
      if (Len == 0) {
        if (OS)
          *OS << "Badly formed extended line op (length 0)\n";
        continue;
      }

      uint8_t SubOpcode = DebugLineData.getU8(OffsetPtr);
      if (OS)
        *OS << LNExtendedString(SubOpcode);
      switch (SubOpcode) {
      case DW_LNE_end_sequence:
        // Set the end_sequence register of the state machine to true and
        // append a row to the matrix using the current values of the
        // state-machine registers. Then reset the registers to the initial
        // values specified above. Every statement program sequence must end
        // with a DW_LNE_end_sequence instruction which creates a row whose
        // address is that of the byte after the last target machine instruction
        // of the sequence.
        State.Row.EndSequence = true;
        State.appendRowToMatrix(*OffsetPtr);
        if (OS) {
          *OS << "\n";
          OS->indent(12);
          State.Row.dump(*OS);
        }
        State.resetRowAndSequence();
        break;

      case DW_LNE_set_address:
        // Takes a single relocatable address as an operand. The size of the
        // operand is the size appropriate to hold an address on the target
        // machine. Set the address register to the value given by the
        // relocatable address. All of the other statement program opcodes
        // that affect the address register add a delta to it. This instruction
        // stores a relocatable value into it instead.
        //
        // Make sure the extractor knows the address size.  If not, infer it
        // from the size of the operand.
        if (DebugLineData.getAddressSize() == 0)
          DebugLineData.setAddressSize(Len - 1);
        else
          assert(DebugLineData.getAddressSize() == Len - 1);
        State.Row.Address = DebugLineData.getRelocatedAddress(OffsetPtr);
        if (OS)
          *OS << format(" (0x%16.16" PRIx64 ")", State.Row.Address);
        break;

      case DW_LNE_define_file:
        // Takes 4 arguments. The first is a null terminated string containing
        // a source file name. The second is an unsigned LEB128 number
        // representing the directory index of the directory in which the file
        // was found. The third is an unsigned LEB128 number representing the
        // time of last modification of the file. The fourth is an unsigned
        // LEB128 number representing the length in bytes of the file. The time
        // and length fields may contain LEB128(0) if the information is not
        // available.
//.........这里部分代码省略.........

Error RangeListEntry::extract(DWARFDataExtractor Data, uint32_t End,
                              uint32_t *OffsetPtr) {
  Offset = *OffsetPtr;
  SectionIndex = -1ULL;
  // The caller should guarantee that we have at least 1 byte available, so
  // we just assert instead of revalidate.
  assert(*OffsetPtr < End &&
         "not enough space to extract a rangelist encoding");
  uint8_t Encoding = Data.getU8(OffsetPtr);

  switch (Encoding) {
  case dwarf::DW_RLE_end_of_list:
    Value0 = Value1 = 0;
    break;
  // TODO: Support other encodings.
  case dwarf::DW_RLE_base_addressx:
    return createError("unsupported rnglists encoding DW_RLE_base_addressx "
                       "at offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_startx_endx:
    return createError("unsupported rnglists encoding DW_RLE_startx_endx at "
                       "offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_startx_length:
    return createError("unsupported rnglists encoding DW_RLE_startx_length "
                       "at offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_offset_pair: {
    uint32_t PreviousOffset = *OffsetPtr - 1;
    Value0 = Data.getULEB128(OffsetPtr);
    Value1 = Data.getULEB128(OffsetPtr);
    if (End < *OffsetPtr)
      return createError("read past end of table when reading "
                         "DW_RLE_offset_pair encoding at offset 0x%" PRIx32,
                         PreviousOffset);
    break;
  }
  case dwarf::DW_RLE_base_address: {
    if ((End - *OffsetPtr) < Data.getAddressSize())
      return createError("insufficient space remaining in table for "
                         "DW_RLE_base_address encoding at offset 0x%" PRIx32,
                         *OffsetPtr - 1);
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    break;
  }
  case dwarf::DW_RLE_start_end: {
    if ((End - *OffsetPtr) < unsigned(Data.getAddressSize() * 2))
      return createError("insufficient space remaining in table for "
                         "DW_RLE_start_end encoding "
                         "at offset 0x%" PRIx32,
                         *OffsetPtr - 1);
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    Value1 = Data.getRelocatedAddress(OffsetPtr);
    break;
  }
  case dwarf::DW_RLE_start_length: {
    uint32_t PreviousOffset = *OffsetPtr - 1;
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    Value1 = Data.getULEB128(OffsetPtr);
    if (End < *OffsetPtr)
      return createError("read past end of table when reading "
                         "DW_RLE_start_length encoding at offset 0x%" PRIx32,
                         PreviousOffset);
    break;
  }
  default:
    return createError("unknown rnglists encoding 0x%" PRIx32
                       " at offset 0x%" PRIx32,
                       uint32_t(Encoding), *OffsetPtr - 1);
  }

  EntryKind = Encoding;
  return Error::success();
}