Example #1
0
// Parse v2-v4 directory and file tables.
static void
parseV2DirFileTables(const DWARFDataExtractor &DebugLineData,
                     uint32_t *OffsetPtr, uint64_t EndPrologueOffset,
                     DWARFDebugLine::ContentTypeTracker &ContentTypes,
                     std::vector<DWARFFormValue> &IncludeDirectories,
                     std::vector<DWARFDebugLine::FileNameEntry> &FileNames) {
  while (*OffsetPtr < EndPrologueOffset) {
    StringRef S = DebugLineData.getCStrRef(OffsetPtr);
    if (S.empty())
      break;
    DWARFFormValue Dir =
        DWARFFormValue::createFromPValue(dwarf::DW_FORM_string, S.data());
    IncludeDirectories.push_back(Dir);
  }

  while (*OffsetPtr < EndPrologueOffset) {
    StringRef Name = DebugLineData.getCStrRef(OffsetPtr);
    if (Name.empty())
      break;
    DWARFDebugLine::FileNameEntry FileEntry;
    FileEntry.Name =
        DWARFFormValue::createFromPValue(dwarf::DW_FORM_string, Name.data());
    FileEntry.DirIdx = DebugLineData.getULEB128(OffsetPtr);
    FileEntry.ModTime = DebugLineData.getULEB128(OffsetPtr);
    FileEntry.Length = DebugLineData.getULEB128(OffsetPtr);
    FileNames.push_back(FileEntry);
  }

  ContentTypes.HasModTime = true;
  ContentTypes.HasLength = true;
}
Example #2
0
// Parse v5 directory/file entry content descriptions.
// Returns the descriptors, or an empty vector if we did not find a path or
// ran off the end of the prologue.
static ContentDescriptors
parseV5EntryFormat(const DWARFDataExtractor &DebugLineData, uint32_t *OffsetPtr,
                   uint64_t EndPrologueOffset, bool *HasMD5) {
  ContentDescriptors Descriptors;
  int FormatCount = DebugLineData.getU8(OffsetPtr);
  bool HasPath = false;
  for (int I = 0; I != FormatCount; ++I) {
    if (*OffsetPtr >= EndPrologueOffset)
      return ContentDescriptors();
    ContentDescriptor Descriptor;
    Descriptor.Type =
      dwarf::LineNumberEntryFormat(DebugLineData.getULEB128(OffsetPtr));
    Descriptor.Form = dwarf::Form(DebugLineData.getULEB128(OffsetPtr));
    if (Descriptor.Type == dwarf::DW_LNCT_path)
      HasPath = true;
    else if (Descriptor.Type == dwarf::DW_LNCT_MD5 && HasMD5)
      *HasMD5 = true;
    Descriptors.push_back(Descriptor);
  }
  return HasPath ? Descriptors : ContentDescriptors();
}
Example #3
0
// Parse v2-v4 directory and file tables.
static void
parseV2DirFileTables(const DWARFDataExtractor &DebugLineData,
                     uint32_t *OffsetPtr, uint64_t EndPrologueOffset,
                     std::vector<StringRef> &IncludeDirectories,
                     std::vector<DWARFDebugLine::FileNameEntry> &FileNames) {
  while (*OffsetPtr < EndPrologueOffset) {
    StringRef S = DebugLineData.getCStrRef(OffsetPtr);
    if (S.empty())
      break;
    IncludeDirectories.push_back(S);
  }

  while (*OffsetPtr < EndPrologueOffset) {
    StringRef Name = DebugLineData.getCStrRef(OffsetPtr);
    if (Name.empty())
      break;
    DWARFDebugLine::FileNameEntry FileEntry;
    FileEntry.Name = Name;
    FileEntry.DirIdx = DebugLineData.getULEB128(OffsetPtr);
    FileEntry.ModTime = DebugLineData.getULEB128(OffsetPtr);
    FileEntry.Length = DebugLineData.getULEB128(OffsetPtr);
    FileNames.push_back(FileEntry);
  }
}
Example #4
0
bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data,
                                  uint32_t *OffsetPtr, DWARFFormParams FP,
                                  const DWARFUnit *CU) {
  U = CU;
  bool Indirect = false;
  bool IsBlock = false;
  Value.data = nullptr;
  // Read the value for the form into value and follow and DW_FORM_indirect
  // instances we run into
  do {
    Indirect = false;
    switch (Form) {
    case DW_FORM_addr:
    case DW_FORM_ref_addr: {
      uint16_t Size =
          (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize();
      Value.uval = Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex);
      break;
    }
    case DW_FORM_exprloc:
    case DW_FORM_block:
      Value.uval = Data.getULEB128(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block1:
      Value.uval = Data.getU8(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block2:
      Value.uval = Data.getU16(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block4:
      Value.uval = Data.getU32(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_data1:
    case DW_FORM_ref1:
    case DW_FORM_flag:
    case DW_FORM_strx1:
    case DW_FORM_addrx1:
      Value.uval = Data.getU8(OffsetPtr);
      break;
    case DW_FORM_data2:
    case DW_FORM_ref2:
    case DW_FORM_strx2:
    case DW_FORM_addrx2:
      Value.uval = Data.getU16(OffsetPtr);
      break;
    case DW_FORM_strx3:
      Value.uval = Data.getU24(OffsetPtr);
      break;
    case DW_FORM_data4:
    case DW_FORM_ref4:
    case DW_FORM_ref_sup4:
    case DW_FORM_strx4:
    case DW_FORM_addrx4:
      Value.uval = Data.getRelocatedValue(4, OffsetPtr);
      break;
    case DW_FORM_data8:
    case DW_FORM_ref8:
    case DW_FORM_ref_sup8:
      Value.uval = Data.getU64(OffsetPtr);
      break;
    case DW_FORM_data16:
      // Treat this like a 16-byte block.
      Value.uval = 16;
      IsBlock = true;
      break;
    case DW_FORM_sdata:
      Value.sval = Data.getSLEB128(OffsetPtr);
      break;
    case DW_FORM_udata:
    case DW_FORM_ref_udata:
      Value.uval = Data.getULEB128(OffsetPtr);
      break;
    case DW_FORM_string:
      Value.cstr = Data.getCStr(OffsetPtr);
      break;
    case DW_FORM_indirect:
      Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr));
      Indirect = true;
      break;
    case DW_FORM_strp:
    case DW_FORM_sec_offset:
    case DW_FORM_GNU_ref_alt:
    case DW_FORM_GNU_strp_alt:
    case DW_FORM_line_strp:
    case DW_FORM_strp_sup: {
      Value.uval =
          Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), OffsetPtr);
      break;
    }
    case DW_FORM_flag_present:
      Value.uval = 1;
      break;
    case DW_FORM_ref_sig8:
      Value.uval = Data.getU64(OffsetPtr);
      break;
    case DW_FORM_GNU_addr_index:
    case DW_FORM_GNU_str_index:
    case DW_FORM_strx:
      Value.uval = Data.getULEB128(OffsetPtr);
      break;
    default:
      // DWARFFormValue::skipValue() will have caught this and caused all
      // DWARF DIEs to fail to be parsed, so this code is not be reachable.
      llvm_unreachable("unsupported form");
    }
  } while (Indirect);

  if (IsBlock) {
    StringRef Str = Data.getData().substr(*OffsetPtr, Value.uval);
    Value.data = nullptr;
    if (!Str.empty()) {
      Value.data = reinterpret_cast<const uint8_t *>(Str.data());
      *OffsetPtr += Value.uval;
    }
  }

  return true;
}
Example #5
0
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.
        //
        // The directory index represents an entry in the include_directories
        // section of the statement program prologue. The index is LEB128(0)
        // if the file was found in the current directory of the compilation,
        // LEB128(1) if it was found in the first directory in the
        // include_directories section, and so on. The directory index is
        // ignored for file names that represent full path names.
        //
        // The files are numbered, starting at 1, in the order in which they
        // appear; the names in the prologue come before names defined by
        // the DW_LNE_define_file instruction. These numbers are used in the
        // the file register of the state machine.
        {
          FileNameEntry FileEntry;
          FileEntry.Name = DebugLineData.getCStr(OffsetPtr);
          FileEntry.DirIdx = DebugLineData.getULEB128(OffsetPtr);
          FileEntry.ModTime = DebugLineData.getULEB128(OffsetPtr);
          FileEntry.Length = DebugLineData.getULEB128(OffsetPtr);
          Prologue.FileNames.push_back(FileEntry);
          if (OS)
            *OS << " (" << FileEntry.Name.str()
                << ", dir=" << FileEntry.DirIdx << ", mod_time="
                << format("(0x%16.16" PRIx64 ")", FileEntry.ModTime)
                << ", length=" << FileEntry.Length << ")";
        }
        break;

      case DW_LNE_set_discriminator:
        State.Row.Discriminator = DebugLineData.getULEB128(OffsetPtr);
        if (OS)
          *OS << " (" << State.Row.Discriminator << ")";
        break;

      default:
        if (OS)
          *OS << format("Unrecognized extended op 0x%02.02" PRIx8, SubOpcode)
              << format(" length %" PRIx64, Len);
        // Len doesn't include the zero opcode byte or the length itself, but
        // it does include the sub_opcode, so we have to adjust for that.
        (*OffsetPtr) += Len - 1;
        break;
      }
      // Make sure the stated and parsed lengths are the same.
      // Otherwise we have an unparseable line-number program.
      if (*OffsetPtr - ExtOffset != Len) {
        fprintf(stderr, "Unexpected line op length at offset 0x%8.8" PRIx32
                " expected 0x%2.2" PRIx64 " found 0x%2.2" PRIx32 "\n",
                ExtOffset, Len, *OffsetPtr - ExtOffset);
        // Skip the rest of the line-number program.
        *OffsetPtr = EndOffset;
        return false;
      }
    } else if (Opcode < Prologue.OpcodeBase) {
      if (OS)
        *OS << LNStandardString(Opcode);
      switch (Opcode) {
      // Standard Opcodes
      case DW_LNS_copy:
        // Takes no arguments. Append a row to the matrix using the
        // current values of the state-machine registers. Then set
        // the basic_block register to false.
        State.appendRowToMatrix(*OffsetPtr);
        if (OS) {
          *OS << "\n";
          OS->indent(12);
          State.Row.dump(*OS);
          *OS << "\n";
        }
        break;

      case DW_LNS_advance_pc:
        // Takes a single unsigned LEB128 operand, multiplies it by the
        // min_inst_length field of the prologue, and adds the
        // result to the address register of the state machine.
        {
          uint64_t AddrOffset =
              DebugLineData.getULEB128(OffsetPtr) * Prologue.MinInstLength;
          State.Row.Address += AddrOffset;
          if (OS)
            *OS << " (" << AddrOffset << ")";
        }
        break;

      case DW_LNS_advance_line:
        // Takes a single signed LEB128 operand and adds that value to
        // the line register of the state machine.
        State.Row.Line += DebugLineData.getSLEB128(OffsetPtr);
        if (OS)
          *OS << " (" << State.Row.Line << ")";
        break;

      case DW_LNS_set_file:
        // Takes a single unsigned LEB128 operand and stores it in the file
        // register of the state machine.
        State.Row.File = DebugLineData.getULEB128(OffsetPtr);
        if (OS)
          *OS << " (" << State.Row.File << ")";
        break;

      case DW_LNS_set_column:
        // Takes a single unsigned LEB128 operand and stores it in the
        // column register of the state machine.
        State.Row.Column = DebugLineData.getULEB128(OffsetPtr);
        if (OS)
          *OS << " (" << State.Row.Column << ")";
        break;

      case DW_LNS_negate_stmt:
        // Takes no arguments. Set the is_stmt register of the state
        // machine to the logical negation of its current value.
        State.Row.IsStmt = !State.Row.IsStmt;
        break;

      case DW_LNS_set_basic_block:
        // Takes no arguments. Set the basic_block register of the
        // state machine to true
        State.Row.BasicBlock = true;
        break;

      case DW_LNS_const_add_pc:
        // Takes no arguments. Add to the address register of the state
        // machine the address increment value corresponding to special
        // opcode 255. The motivation for DW_LNS_const_add_pc is this:
        // when the statement program needs to advance the address by a
        // small amount, it can use a single special opcode, which occupies
        // a single byte. When it needs to advance the address by up to
        // twice the range of the last special opcode, it can use
        // DW_LNS_const_add_pc followed by a special opcode, for a total
        // of two bytes. Only if it needs to advance the address by more
        // than twice that range will it need to use both DW_LNS_advance_pc
        // and a special opcode, requiring three or more bytes.
        {
          uint8_t AdjustOpcode = 255 - Prologue.OpcodeBase;
          uint64_t AddrOffset =
              (AdjustOpcode / Prologue.LineRange) * Prologue.MinInstLength;
          State.Row.Address += AddrOffset;
          if (OS)
            *OS
                << format(" (0x%16.16" PRIx64 ")", AddrOffset);
        }
        break;

      case DW_LNS_fixed_advance_pc:
        // Takes a single uhalf operand. Add to the address register of
        // the state machine the value of the (unencoded) operand. This
        // is the only extended opcode that takes an argument that is not
        // a variable length number. The motivation for DW_LNS_fixed_advance_pc
        // is this: existing assemblers cannot emit DW_LNS_advance_pc or
        // special opcodes because they cannot encode LEB128 numbers or
        // judge when the computation of a special opcode overflows and
        // requires the use of DW_LNS_advance_pc. Such assemblers, however,
        // can use DW_LNS_fixed_advance_pc instead, sacrificing compression.
        {
          uint16_t PCOffset = DebugLineData.getU16(OffsetPtr);
          State.Row.Address += PCOffset;
          if (OS)
            *OS
                << format(" (0x%16.16" PRIx64 ")", PCOffset);
        }
        break;

      case DW_LNS_set_prologue_end:
        // Takes no arguments. Set the prologue_end register of the
        // state machine to true
        State.Row.PrologueEnd = true;
        break;

      case DW_LNS_set_epilogue_begin:
        // Takes no arguments. Set the basic_block register of the
        // state machine to true
        State.Row.EpilogueBegin = true;
        break;

      case DW_LNS_set_isa:
        // Takes a single unsigned LEB128 operand and stores it in the
        // column register of the state machine.
        State.Row.Isa = DebugLineData.getULEB128(OffsetPtr);
        if (OS)
          *OS << " (" << State.Row.Isa << ")";
        break;

      default:
        // Handle any unknown standard opcodes here. We know the lengths
        // of such opcodes because they are specified in the prologue
        // as a multiple of LEB128 operands for each opcode.
        {
          assert(Opcode - 1U < Prologue.StandardOpcodeLengths.size());
          uint8_t OpcodeLength = Prologue.StandardOpcodeLengths[Opcode - 1];
          for (uint8_t I = 0; I < OpcodeLength; ++I) {
            uint64_t Value = DebugLineData.getULEB128(OffsetPtr);
            if (OS)
              *OS << format("Skipping ULEB128 value: 0x%16.16" PRIx64 ")\n",
                            Value);
          }
        }
        break;
      }
    } else {
      // Special Opcodes

      // A special opcode value is chosen based on the amount that needs
      // to be added to the line and address registers. The maximum line
      // increment for a special opcode is the value of the line_base
      // field in the header, plus the value of the line_range field,
      // minus 1 (line base + line range - 1). If the desired line
      // increment is greater than the maximum line increment, a standard
      // opcode must be used instead of a special opcode. The "address
      // advance" is calculated by dividing the desired address increment
      // by the minimum_instruction_length field from the header. The
      // special opcode is then calculated using the following formula:
      //
      //  opcode = (desired line increment - line_base) +
      //           (line_range * address advance) + opcode_base
      //
      // If the resulting opcode is greater than 255, a standard opcode
      // must be used instead.
      //
      // To decode a special opcode, subtract the opcode_base from the
      // opcode itself to give the adjusted opcode. The amount to
      // increment the address register is the result of the adjusted
      // opcode divided by the line_range multiplied by the
      // minimum_instruction_length field from the header. That is:
      //
      //  address increment = (adjusted opcode / line_range) *
      //                      minimum_instruction_length
      //
      // The amount to increment the line register is the line_base plus
      // the result of the adjusted opcode modulo the line_range. That is:
      //
      // line increment = line_base + (adjusted opcode % line_range)

      uint8_t AdjustOpcode = Opcode - Prologue.OpcodeBase;
      uint64_t AddrOffset =
          (AdjustOpcode / Prologue.LineRange) * Prologue.MinInstLength;
      int32_t LineOffset =
          Prologue.LineBase + (AdjustOpcode % Prologue.LineRange);
      State.Row.Line += LineOffset;
      State.Row.Address += AddrOffset;

      if (OS) {
        *OS << "address += " << ((uint32_t)AdjustOpcode)
            << ",  line += " << LineOffset << "\n";
        OS->indent(12);
        State.Row.dump(*OS);
      }

      State.appendRowToMatrix(*OffsetPtr);
      // Reset discriminator to 0.
      State.Row.Discriminator = 0;
    }
    if(OS)
      *OS << "\n";
  }

  if (!State.Sequence.Empty) {
    fprintf(stderr, "warning: last sequence in debug line table is not"
                    "terminated!\n");
  }

  // Sort all sequences so that address lookup will work faster.
  if (!Sequences.empty()) {
    std::sort(Sequences.begin(), Sequences.end(), Sequence::orderByLowPC);
    // Note: actually, instruction address ranges of sequences should not
    // overlap (in shared objects and executables). If they do, the address
    // lookup would still work, though, but result would be ambiguous.
    // We don't report warning in this case. For example,
    // sometimes .so compiled from multiple object files contains a few
    // rudimentary sequences for address ranges [0x0, 0xsomething).
  }

  return EndOffset;
}
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();
}