C++ DWARFDie::getDwarfUnit方法代码示例

static bool isVariableIndexable(const DWARFDie &Die, DWARFContext &DCtx) {
  Optional<DWARFFormValue> Location = Die.findRecursively(DW_AT_location);
  if (!Location)
    return false;

  auto ContainsInterestingOperators = [&](StringRef D) {
    DWARFUnit *U = Die.getDwarfUnit();
    DataExtractor Data(D, DCtx.isLittleEndian(), U->getAddressByteSize());
    DWARFExpression Expression(Data, U->getVersion(), U->getAddressByteSize());
    return any_of(Expression, [](DWARFExpression::Operation &Op) {
      return !Op.isError() && (Op.getCode() == DW_OP_addr ||
                               Op.getCode() == DW_OP_form_tls_address ||
                               Op.getCode() == DW_OP_GNU_push_tls_address);
    });
  };

  if (Optional<ArrayRef<uint8_t>> Expr = Location->getAsBlock()) {
    // Inlined location.
    if (ContainsInterestingOperators(toStringRef(*Expr)))
      return true;
  } else if (Optional<uint64_t> Offset = Location->getAsSectionOffset()) {
    // Location list.
    if (const DWARFDebugLoc *DebugLoc = DCtx.getDebugLoc()) {
      if (const DWARFDebugLoc::LocationList *LocList =
              DebugLoc->getLocationListAtOffset(*Offset)) {
        if (any_of(LocList->Entries, [&](const DWARFDebugLoc::Entry &E) {
              return ContainsInterestingOperators({E.Loc.data(), E.Loc.size()});
            }))
          return true;
      }
    }
  }
  return false;
}

unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
                                                 DWARFAttribute &AttrValue) {
  unsigned NumErrors = 0;
  auto ReportError = [&](const Twine &TitleMsg) {
    ++NumErrors;
    error() << TitleMsg << '\n';
    Die.dump(OS, 0, DumpOpts);
    OS << "\n";
  };

  const DWARFObject &DObj = DCtx.getDWARFObj();
  const auto Attr = AttrValue.Attr;
  switch (Attr) {
  case DW_AT_ranges:
    // Make sure the offset in the DW_AT_ranges attribute is valid.
    if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
      if (*SectionOffset >= DObj.getRangeSection().Data.size())
        ReportError("DW_AT_ranges offset is beyond .debug_ranges bounds:");
      break;
    }
    ReportError("DIE has invalid DW_AT_ranges encoding:");
    break;
  case DW_AT_stmt_list:
    // Make sure the offset in the DW_AT_stmt_list attribute is valid.
    if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
      if (*SectionOffset >= DObj.getLineSection().Data.size())
        ReportError("DW_AT_stmt_list offset is beyond .debug_line bounds: " +
                    llvm::formatv("{0:x8}", *SectionOffset));
      break;
    }
    ReportError("DIE has invalid DW_AT_stmt_list encoding:");
    break;
  case DW_AT_location: {
    Optional<ArrayRef<uint8_t>> Expr = AttrValue.Value.getAsBlock();
    if (!Expr) {
      ReportError("DIE has invalid DW_AT_location encoding:");
      break;
    }

    DWARFUnit *U = Die.getDwarfUnit();
    DataExtractor Data(
        StringRef(reinterpret_cast<const char *>(Expr->data()), Expr->size()),
        DCtx.isLittleEndian(), 0);
    DWARFExpression Expression(Data, U->getVersion(), U->getAddressByteSize());
    bool Error = llvm::any_of(Expression, [](DWARFExpression::Operation &Op) {
      return Op.isError();
    });
    if (Error)
      ReportError("DIE contains invalid DWARF expression:");
    break;
  }

  default:
    break;
  }
  return NumErrors;
}

static void dumpArrayType(raw_ostream &OS, const DWARFDie &D) {
  Optional<uint64_t> Bound;
  for (const DWARFDie &C : D.children())
    if (C.getTag() == DW_TAG_subrange_type) {
      Optional<uint64_t> LB;
      Optional<uint64_t> Count;
      Optional<uint64_t> UB;
      Optional<unsigned> DefaultLB;
      if (Optional<DWARFFormValue> L = C.find(DW_AT_lower_bound))
        LB = L->getAsUnsignedConstant();
      if (Optional<DWARFFormValue> CountV = C.find(DW_AT_count))
        Count = CountV->getAsUnsignedConstant();
      if (Optional<DWARFFormValue> UpperV = C.find(DW_AT_upper_bound))
        UB = UpperV->getAsUnsignedConstant();
      if (Optional<DWARFFormValue> LV =
              D.getDwarfUnit()->getUnitDIE().find(DW_AT_language))
        if (Optional<uint64_t> LC = LV->getAsUnsignedConstant())
          if ((DefaultLB =
                   LanguageLowerBound(static_cast<dwarf::SourceLanguage>(*LC))))
            if (LB && *LB == *DefaultLB)
              LB = None;
      if (!LB && !Count && !UB)
        OS << "[]";
      else if (!LB && (Count || UB) && DefaultLB)
        OS << '[' << (Count ? *Count : *UB - *DefaultLB + 1) << ']';
      else {
        OS << "[[";
        if (LB)
          OS << *LB;
        else
          OS << '?';
        OS << ", ";
        if (Count)
          if (LB)
            OS << *LB + *Count;
          else
            OS << "? + " << *Count;
        else if (UB)
          OS << *UB + 1;
        else
          OS << '?';
        OS << ")]";
      }
    }
}

unsigned DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die,
                                            DWARFAttribute &AttrValue) {
  const DWARFObject &DObj = DCtx.getDWARFObj();
  unsigned NumErrors = 0;
  const auto Form = AttrValue.Value.getForm();
  switch (Form) {
  case DW_FORM_ref1:
  case DW_FORM_ref2:
  case DW_FORM_ref4:
  case DW_FORM_ref8:
  case DW_FORM_ref_udata: {
    // Verify all CU relative references are valid CU offsets.
    Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
    assert(RefVal);
    if (RefVal) {
      auto DieCU = Die.getDwarfUnit();
      auto CUSize = DieCU->getNextUnitOffset() - DieCU->getOffset();
      auto CUOffset = AttrValue.Value.getRawUValue();
      if (CUOffset >= CUSize) {
        ++NumErrors;
        error() << FormEncodingString(Form) << " CU offset "
                << format("0x%08" PRIx64, CUOffset)
                << " is invalid (must be less than CU size of "
                << format("0x%08" PRIx32, CUSize) << "):\n";
        Die.dump(OS, 0, DumpOpts);
        OS << "\n";
      } else {
        // Valid reference, but we will verify it points to an actual
        // DIE later.
        ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
      }
    }
    break;
  }
  case DW_FORM_ref_addr: {
    // Verify all absolute DIE references have valid offsets in the
    // .debug_info section.
    Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
    assert(RefVal);
    if (RefVal) {
      if (*RefVal >= DObj.getInfoSection().Data.size()) {
        ++NumErrors;
        error() << "DW_FORM_ref_addr offset beyond .debug_info "
                   "bounds:\n";
        Die.dump(OS, 0, DumpOpts);
        OS << "\n";
      } else {
        // Valid reference, but we will verify it points to an actual
        // DIE later.
        ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
      }
    }
    break;
  }
  case DW_FORM_strp: {
    auto SecOffset = AttrValue.Value.getAsSectionOffset();
    assert(SecOffset); // DW_FORM_strp is a section offset.
    if (SecOffset && *SecOffset >= DObj.getStringSection().size()) {
      ++NumErrors;
      error() << "DW_FORM_strp offset beyond .debug_str bounds:\n";
      Die.dump(OS, 0, DumpOpts);
      OS << "\n";
    }
    break;
  }
  default:
    break;
  }
  return NumErrors;
}

unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
                                                 DWARFAttribute &AttrValue) {
  unsigned NumErrors = 0;
  auto ReportError = [&](const Twine &TitleMsg) {
    ++NumErrors;
    error() << TitleMsg << '\n';
    Die.dump(OS, 0, DumpOpts);
    OS << "\n";
  };

  const DWARFObject &DObj = DCtx.getDWARFObj();
  const auto Attr = AttrValue.Attr;
  switch (Attr) {
  case DW_AT_ranges:
    // Make sure the offset in the DW_AT_ranges attribute is valid.
    if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
      if (*SectionOffset >= DObj.getRangeSection().Data.size())
        ReportError("DW_AT_ranges offset is beyond .debug_ranges bounds:");
      break;
    }
    ReportError("DIE has invalid DW_AT_ranges encoding:");
    break;
  case DW_AT_stmt_list:
    // Make sure the offset in the DW_AT_stmt_list attribute is valid.
    if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
      if (*SectionOffset >= DObj.getLineSection().Data.size())
        ReportError("DW_AT_stmt_list offset is beyond .debug_line bounds: " +
                    llvm::formatv("{0:x8}", *SectionOffset));
      break;
    }
    ReportError("DIE has invalid DW_AT_stmt_list encoding:");
    break;
  case DW_AT_location: {
    auto VerifyLocation = [&](StringRef D) {
      DWARFUnit *U = Die.getDwarfUnit();
      DataExtractor Data(D, DCtx.isLittleEndian(), 0);
      DWARFExpression Expression(Data, U->getVersion(),
                                 U->getAddressByteSize());
      bool Error = llvm::any_of(Expression, [](DWARFExpression::Operation &Op) {
        return Op.isError();
      });
      if (Error)
        ReportError("DIE contains invalid DWARF expression:");
    };
    if (Optional<ArrayRef<uint8_t>> Expr = AttrValue.Value.getAsBlock()) {
      // Verify inlined location.
      VerifyLocation(llvm::toStringRef(*Expr));
    } else if (auto LocOffset = AttrValue.Value.getAsUnsignedConstant()) {
      // Verify location list.
      if (auto DebugLoc = DCtx.getDebugLoc())
        if (auto LocList = DebugLoc->getLocationListAtOffset(*LocOffset))
          for (const auto &Entry : LocList->Entries)
            VerifyLocation({Entry.Loc.data(), Entry.Loc.size()});
    }
    break;
  }

  default:
    break;
  }
  return NumErrors;
}

static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
                          uint32_t *OffsetPtr, dwarf::Attribute Attr,
                          dwarf::Form Form, unsigned Indent) {
  if (!Die.isValid())
    return;
  const char BaseIndent[] = "            ";
  OS << BaseIndent;
  OS.indent(Indent+2);
  auto attrString = AttributeString(Attr);
  if (!attrString.empty())
    WithColor(OS, syntax::Attribute) << attrString;
  else
    WithColor(OS, syntax::Attribute).get() << format("DW_AT_Unknown_%x", Attr);
  
  auto formString = FormEncodingString(Form);
  if (!formString.empty())
    OS << " [" << formString << ']';
  else
    OS << format(" [DW_FORM_Unknown_%x]", Form);
  
  DWARFUnit *U = Die.getDwarfUnit();
  DWARFFormValue formValue(Form);
  
  if (!formValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr, U))
    return;
  
  OS << "\t(";
  
  StringRef Name;
  std::string File;
  auto Color = syntax::Enumerator;
  if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
    Color = syntax::String;
    if (const auto *LT = U->getContext().getLineTableForUnit(U))
      if (LT->getFileNameByIndex(formValue.getAsUnsignedConstant().getValue(), U->getCompilationDir(), DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
        File = '"' + File + '"';
        Name = File;
      }
  } else if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())
    Name = AttributeValueString(Attr, *Val);
  
  if (!Name.empty())
    WithColor(OS, Color) << Name;
  else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line)
    OS << *formValue.getAsUnsignedConstant();
  else
    formValue.dump(OS);
  
  // We have dumped the attribute raw value. For some attributes
  // having both the raw value and the pretty-printed value is
  // interesting. These attributes are handled below.
  if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
    if (const char *Name = Die.getAttributeValueAsReferencedDie(Attr).getName(DINameKind::LinkageName))
        OS << " \"" << Name << '\"';
  } else if (Attr == DW_AT_APPLE_property_attribute) {
    if (Optional<uint64_t> OptVal = formValue.getAsUnsignedConstant())
      dumpApplePropertyAttribute(OS, *OptVal);
  } else if (Attr == DW_AT_ranges) {
    dumpRanges(OS, Die.getAddressRanges(), U->getAddressByteSize(),
               sizeof(BaseIndent)+Indent+4);
  }
  
  OS << ")\n";
}

static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
                          uint32_t *OffsetPtr, dwarf::Attribute Attr,
                          dwarf::Form Form, unsigned Indent,
                          DIDumpOptions DumpOpts) {
  if (!Die.isValid())
    return;
  const char BaseIndent[] = "            ";
  OS << BaseIndent;
  OS.indent(Indent + 2);
  WithColor(OS, HighlightColor::Attribute) << formatv("{0}", Attr);

  if (DumpOpts.Verbose || DumpOpts.ShowForm)
    OS << formatv(" [{0}]", Form);

  DWARFUnit *U = Die.getDwarfUnit();
  DWARFFormValue FormValue = DWARFFormValue::createFromUnit(Form, U, OffsetPtr);

  OS << "\t(";

  StringRef Name;
  std::string File;
  auto Color = HighlightColor::Enumerator;
  if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
    Color = HighlightColor::String;
    if (const auto *LT = U->getContext().getLineTableForUnit(U))
      if (LT->getFileNameByIndex(
              FormValue.getAsUnsignedConstant().getValue(),
              U->getCompilationDir(),
              DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
        File = '"' + File + '"';
        Name = File;
      }
  } else if (Optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
    Name = AttributeValueString(Attr, *Val);

  if (!Name.empty())
    WithColor(OS, Color) << Name;
  else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line)
    OS << *FormValue.getAsUnsignedConstant();
  else if (Attr == DW_AT_high_pc && !DumpOpts.ShowForm && !DumpOpts.Verbose &&
           FormValue.getAsUnsignedConstant()) {
    if (DumpOpts.ShowAddresses) {
      // Print the actual address rather than the offset.
      uint64_t LowPC, HighPC, Index;
      if (Die.getLowAndHighPC(LowPC, HighPC, Index))
        OS << format("0x%016" PRIx64, HighPC);
      else
        FormValue.dump(OS, DumpOpts);
    }
  } else if (DWARFAttribute::mayHaveLocationDescription(Attr))
    dumpLocation(OS, FormValue, U, sizeof(BaseIndent) + Indent + 4, DumpOpts);
  else
    FormValue.dump(OS, DumpOpts);

  std::string Space = DumpOpts.ShowAddresses ? " " : "";

  // We have dumped the attribute raw value. For some attributes
  // having both the raw value and the pretty-printed value is
  // interesting. These attributes are handled below.
  if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
    if (const char *Name =
            Die.getAttributeValueAsReferencedDie(FormValue).getName(
                DINameKind::LinkageName))
      OS << Space << "\"" << Name << '\"';
  } else if (Attr == DW_AT_type) {
    OS << Space << "\"";
    dumpTypeName(OS, Die.getAttributeValueAsReferencedDie(FormValue));
    OS << '"';
  } else if (Attr == DW_AT_APPLE_property_attribute) {
    if (Optional<uint64_t> OptVal = FormValue.getAsUnsignedConstant())
      dumpApplePropertyAttribute(OS, *OptVal);
  } else if (Attr == DW_AT_ranges) {
    const DWARFObject &Obj = Die.getDwarfUnit()->getContext().getDWARFObj();
    // For DW_FORM_rnglistx we need to dump the offset separately, since
    // we have only dumped the index so far.
    if (FormValue.getForm() == DW_FORM_rnglistx)
      if (auto RangeListOffset =
              U->getRnglistOffset(*FormValue.getAsSectionOffset())) {
        DWARFFormValue FV = DWARFFormValue::createFromUValue(
            dwarf::DW_FORM_sec_offset, *RangeListOffset);
        FV.dump(OS, DumpOpts);
      }
    if (auto RangesOrError = Die.getAddressRanges())
      dumpRanges(Obj, OS, RangesOrError.get(), U->getAddressByteSize(),
                 sizeof(BaseIndent) + Indent + 4, DumpOpts);
    else
      WithColor::error() << "decoding address ranges: "
                         << toString(RangesOrError.takeError()) << '\n';
  }

  OS << ")\n";
}

static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
                          uint32_t *OffsetPtr, dwarf::Attribute Attr,
                          dwarf::Form Form, unsigned Indent,
                          DIDumpOptions DumpOpts) {
  if (!Die.isValid())
    return;
  const char BaseIndent[] = "            ";
  OS << BaseIndent;
  OS.indent(Indent + 2);
  auto attrString = AttributeString(Attr);
  if (!attrString.empty())
    WithColor(OS, HighlightColor::Attribute) << attrString;
  else
    WithColor(OS, HighlightColor::Attribute).get()
        << format("DW_AT_Unknown_%x", Attr);

  if (DumpOpts.Verbose || DumpOpts.ShowForm) {
    auto formString = FormEncodingString(Form);
    if (!formString.empty())
      OS << " [" << formString << ']';
    else
      OS << format(" [DW_FORM_Unknown_%x]", Form);
  }

  DWARFUnit *U = Die.getDwarfUnit();
  DWARFFormValue formValue(Form);

  if (!formValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr,
                              U->getFormParams(), U))
    return;

  OS << "\t(";

  StringRef Name;
  std::string File;
  auto Color = HighlightColor::Enumerator;
  if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
    Color = HighlightColor::String;
    if (const auto *LT = U->getContext().getLineTableForUnit(U))
      if (LT->getFileNameByIndex(
              formValue.getAsUnsignedConstant().getValue(),
              U->getCompilationDir(),
              DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
        File = '"' + File + '"';
        Name = File;
      }
  } else if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())
    Name = AttributeValueString(Attr, *Val);

  if (!Name.empty())
    WithColor(OS, Color) << Name;
  else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line)
    OS << *formValue.getAsUnsignedConstant();
  else if (Attr == DW_AT_high_pc && !DumpOpts.ShowForm && !DumpOpts.Verbose &&
           formValue.getAsUnsignedConstant()) {
    if (DumpOpts.ShowAddresses) {
      // Print the actual address rather than the offset.
      uint64_t LowPC, HighPC, Index;
      if (Die.getLowAndHighPC(LowPC, HighPC, Index))
        OS << format("0x%016" PRIx64, HighPC);
      else
        formValue.dump(OS, DumpOpts);
    }
  } else if (Attr == DW_AT_location || Attr == DW_AT_frame_base ||
             Attr == DW_AT_data_member_location ||
             Attr == DW_AT_GNU_call_site_value)
    dumpLocation(OS, formValue, U, sizeof(BaseIndent) + Indent + 4, DumpOpts);
  else
    formValue.dump(OS, DumpOpts);

  // We have dumped the attribute raw value. For some attributes
  // having both the raw value and the pretty-printed value is
  // interesting. These attributes are handled below.
  if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
    if (const char *Name = Die.getAttributeValueAsReferencedDie(Attr).getName(
            DINameKind::LinkageName))
      OS << " \"" << Name << '\"';
  } else if (Attr == DW_AT_type) {
    OS << " \"";
    dumpTypeName(OS, Die);
    OS << '"';
  } else if (Attr == DW_AT_APPLE_property_attribute) {
    if (Optional<uint64_t> OptVal = formValue.getAsUnsignedConstant())
      dumpApplePropertyAttribute(OS, *OptVal);
  } else if (Attr == DW_AT_ranges) {
    const DWARFObject &Obj = Die.getDwarfUnit()->getContext().getDWARFObj();
    dumpRanges(Obj, OS, Die.getAddressRanges(), U->getAddressByteSize(),
               sizeof(BaseIndent) + Indent + 4, DumpOpts);
  }

  OS << ")\n";
}

unsigned DWARFVerifier::verifyNameIndexCompleteness(
    const DWARFDie &Die, const DWARFDebugNames::NameIndex &NI) {

  // First check, if the Die should be indexed. The code follows the DWARF v5
  // wording as closely as possible.

  // "All non-defining declarations (that is, debugging information entries
  // with a DW_AT_declaration attribute) are excluded."
  if (Die.find(DW_AT_declaration))
    return 0;

  // "DW_TAG_namespace debugging information entries without a DW_AT_name
  // attribute are included with the name “(anonymous namespace)”.
  // All other debugging information entries without a DW_AT_name attribute
  // are excluded."
  // "If a subprogram or inlined subroutine is included, and has a
  // DW_AT_linkage_name attribute, there will be an additional index entry for
  // the linkage name."
  auto IncludeLinkageName = Die.getTag() == DW_TAG_subprogram ||
                            Die.getTag() == DW_TAG_inlined_subroutine;
  auto EntryNames = getNames(Die, IncludeLinkageName);
  if (EntryNames.empty())
    return 0;

  // We deviate from the specification here, which says:
  // "The name index must contain an entry for each debugging information entry
  // that defines a named subprogram, label, variable, type, or namespace,
  // subject to ..."
  // Instead whitelisting all TAGs representing a "type" or a "subprogram", to
  // make sure we catch any missing items, we instead blacklist all TAGs that we
  // know shouldn't be indexed.
  switch (Die.getTag()) {
  // Compile units and modules have names but shouldn't be indexed.
  case DW_TAG_compile_unit:
  case DW_TAG_module:
    return 0;

  // Function and template parameters are not globally visible, so we shouldn't
  // index them.
  case DW_TAG_formal_parameter:
  case DW_TAG_template_value_parameter:
  case DW_TAG_template_type_parameter:
  case DW_TAG_GNU_template_parameter_pack:
  case DW_TAG_GNU_template_template_param:
    return 0;

  // Object members aren't globally visible.
  case DW_TAG_member:
    return 0;

  // According to a strict reading of the specification, enumerators should not
  // be indexed (and LLVM currently does not do that). However, this causes
  // problems for the debuggers, so we may need to reconsider this.
  case DW_TAG_enumerator:
    return 0;

  // Imported declarations should not be indexed according to the specification
  // and LLVM currently does not do that.
  case DW_TAG_imported_declaration:
    return 0;

  // "DW_TAG_subprogram, DW_TAG_inlined_subroutine, and DW_TAG_label debugging
  // information entries without an address attribute (DW_AT_low_pc,
  // DW_AT_high_pc, DW_AT_ranges, or DW_AT_entry_pc) are excluded."
  case DW_TAG_subprogram:
  case DW_TAG_inlined_subroutine:
  case DW_TAG_label:
    if (Die.findRecursively(
            {DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_entry_pc}))
      break;
    return 0;

  // "DW_TAG_variable debugging information entries with a DW_AT_location
  // attribute that includes a DW_OP_addr or DW_OP_form_tls_address operator are
  // included; otherwise, they are excluded."
  //
  // LLVM extension: We also add DW_OP_GNU_push_tls_address to this list.
  case DW_TAG_variable:
    if (isVariableIndexable(Die, DCtx))
      break;
    return 0;

  default:
    break;
  }

  // Now we know that our Die should be present in the Index. Let's check if
  // that's the case.
  unsigned NumErrors = 0;
  uint64_t DieUnitOffset = Die.getOffset() - Die.getDwarfUnit()->getOffset();
  for (StringRef Name : EntryNames) {
    if (none_of(NI.equal_range(Name), [&](const DWARFDebugNames::Entry &E) {
          return E.getDIEUnitOffset() == DieUnitOffset;
        })) {
      error() << formatv("Name Index @ {0:x}: Entry for DIE @ {1:x} ({2}) with "
                         "name {3} missing.\n",
                         NI.getUnitOffset(), Die.getOffset(), Die.getTag(),
                         Name);
      ++NumErrors;
    }
//.........这里部分代码省略.........

unsigned DWARFVerifier::verifyNameIndexEntries(
    const DWARFDebugNames::NameIndex &NI,
    const DWARFDebugNames::NameTableEntry &NTE) {
  // Verifying type unit indexes not supported.
  if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0)
    return 0;

  const char *CStr = NTE.getString();
  if (!CStr) {
    error() << formatv(
        "Name Index @ {0:x}: Unable to get string associated with name {1}.\n",
        NI.getUnitOffset(), NTE.getIndex());
    return 1;
  }
  StringRef Str(CStr);

  unsigned NumErrors = 0;
  unsigned NumEntries = 0;
  uint32_t EntryID = NTE.getEntryOffset();
  uint32_t NextEntryID = EntryID;
  Expected<DWARFDebugNames::Entry> EntryOr = NI.getEntry(&NextEntryID);
  for (; EntryOr; ++NumEntries, EntryID = NextEntryID,
                                EntryOr = NI.getEntry(&NextEntryID)) {
    uint32_t CUIndex = *EntryOr->getCUIndex();
    if (CUIndex > NI.getCUCount()) {
      error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an "
                         "invalid CU index ({2}).\n",
                         NI.getUnitOffset(), EntryID, CUIndex);
      ++NumErrors;
      continue;
    }
    uint32_t CUOffset = NI.getCUOffset(CUIndex);
    uint64_t DIEOffset = CUOffset + *EntryOr->getDIEUnitOffset();
    DWARFDie DIE = DCtx.getDIEForOffset(DIEOffset);
    if (!DIE) {
      error() << formatv("Name Index @ {0:x}: Entry @ {1:x} references a "
                         "non-existing DIE @ {2:x}.\n",
                         NI.getUnitOffset(), EntryID, DIEOffset);
      ++NumErrors;
      continue;
    }
    if (DIE.getDwarfUnit()->getOffset() != CUOffset) {
      error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched CU of "
                         "DIE @ {2:x}: index - {3:x}; debug_info - {4:x}.\n",
                         NI.getUnitOffset(), EntryID, DIEOffset, CUOffset,
                         DIE.getDwarfUnit()->getOffset());
      ++NumErrors;
    }
    if (DIE.getTag() != EntryOr->tag()) {
      error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Tag of "
                         "DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
                         NI.getUnitOffset(), EntryID, DIEOffset, EntryOr->tag(),
                         DIE.getTag());
      ++NumErrors;
    }

    auto EntryNames = getNames(DIE);
    if (!is_contained(EntryNames, Str)) {
      error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Name "
                         "of DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
                         NI.getUnitOffset(), EntryID, DIEOffset, Str,
                         make_range(EntryNames.begin(), EntryNames.end()));
      ++NumErrors;
    }
  }
  handleAllErrors(EntryOr.takeError(),
                  [&](const DWARFDebugNames::SentinelError &) {
                    if (NumEntries > 0)
                      return;
                    error() << formatv("Name Index @ {0:x}: Name {1} ({2}) is "
                                       "not associated with any entries.\n",
                                       NI.getUnitOffset(), NTE.getIndex(), Str);
                    ++NumErrors;
                  },
                  [&](const ErrorInfoBase &Info) {
                    error()
                        << formatv("Name Index @ {0:x}: Name {1} ({2}): {3}\n",
                                   NI.getUnitOffset(), NTE.getIndex(), Str,
                                   Info.message());
                    ++NumErrors;
                  });
  return NumErrors;
}