[PATCH] D37621: [llvm-readobj] - Refactor printGroupSections methods.

[Rafael Avila de Espindola via llvm-commits]

LGTM

Thanks!


George Rimar via Phabricator <reviews at reviews.llvm.org> writes:

> grimar created this revision.
>
> This refactors `GNUStyle<ELFT>::printGroupSections` and
> `LLVMStyle<ELFT>::printGroupSections` to split out all
> duplicated code.
>
> After the change these methods just prints the data provided
> by introduced `getGroups` in a corresponding LLVM/GNU format.
>
>
> https://reviews.llvm.org/D37621
>
> Files:
>   tools/llvm-readobj/ELFDumper.cpp
>
> Index: tools/llvm-readobj/ELFDumper.cpp
> ===================================================================
> --- tools/llvm-readobj/ELFDumper.cpp
> +++ tools/llvm-readobj/ELFDumper.cpp
> @@ -2441,34 +2441,69 @@
>    printFields(OS, "Section header string table index:", Str);
>  }
>  
> -template <class ELFT> void GNUStyle<ELFT>::printGroupSections(const ELFO *Obj) {
> -  uint32_t SectionIndex = 0;
> -  bool HasGroups = false;
> +namespace {
> +struct GroupMember {
> +  StringRef Name;
> +  uint64_t Index;
> +};
> +
> +struct GroupSection {
> +  StringRef Name;
> +  StringRef Signature;
> +  uint64_t ShName;
> +  uint64_t Index;
> +  uint32_t Type;
> +  std::vector<GroupMember> Members;
> +};
> +
> +template <class ELFT>
> +std::vector<GroupSection> getGroups(const ELFFile<ELFT> *Obj) {
> +  using Elf_Shdr = typename ELFFile<ELFT>::Elf_Shdr;
> +  using Elf_Sym = typename ELFFile<ELFT>::Elf_Sym;
> +  using Elf_Word = typename ELFFile<ELFT>::Elf_Word;
> +
> +  std::vector<GroupSection> Ret;
> +  uint64_t I = 0;
>    for (const Elf_Shdr &Sec : unwrapOrError(Obj->sections())) {
> -    if (Sec.sh_type == ELF::SHT_GROUP) {
> -      HasGroups = true;
> -      const Elf_Shdr *Symtab = unwrapOrError(Obj->getSection(Sec.sh_link));
> -      StringRef StrTable = unwrapOrError(Obj->getStringTableForSymtab(*Symtab));
> -      const Elf_Sym *Signature =
> -          unwrapOrError(Obj->template getEntry<Elf_Sym>(Symtab, Sec.sh_info));
> -      ArrayRef<Elf_Word> Data = unwrapOrError(
> -          Obj->template getSectionContentsAsArray<Elf_Word>(&Sec));
> -      StringRef Name = unwrapOrError(Obj->getSectionName(&Sec));
> -      OS << "\n" << getGroupType(Data[0]) << " group section ["
> -         << format_decimal(SectionIndex, 5) << "] `" << Name << "' ["
> -         << StrTable.data() + Signature->st_name << "] contains "
> -         << (Data.size() - 1) << " sections:\n"
> -         << "   [Index]    Name\n";
> -      for (auto &Ndx : Data.slice(1)) {
> -        auto Sec = unwrapOrError(Obj->getSection(Ndx));
> -        const StringRef Name = unwrapOrError(Obj->getSectionName(Sec));
> -        OS << "   [" << format_decimal(Ndx, 5) << "]   " << Name
> -           << "\n";
> -      }
> +    ++I;
> +    if (Sec.sh_type != ELF::SHT_GROUP)
> +      continue;
> +
> +    const Elf_Shdr *Symtab = unwrapOrError(Obj->getSection(Sec.sh_link));
> +    StringRef StrTable = unwrapOrError(Obj->getStringTableForSymtab(*Symtab));
> +    const Elf_Sym *Sym =
> +        unwrapOrError(Obj->template getEntry<Elf_Sym>(Symtab, Sec.sh_info));
> +    auto Data =
> +        unwrapOrError(Obj->template getSectionContentsAsArray<Elf_Word>(&Sec));
> +
> +    StringRef Name = unwrapOrError(Obj->getSectionName(&Sec));
> +    StringRef Signature = StrTable.data() + Sym->st_name;
> +    Ret.push_back({Name, Signature, Sec.sh_name, I - 1, Data[0], {}});
> +
> +    std::vector<GroupMember> &GM = Ret.back().Members;
> +    for (uint32_t Ndx : Data.slice(1)) {
> +      auto Sec = unwrapOrError(Obj->getSection(Ndx));
> +      const StringRef Name = unwrapOrError(Obj->getSectionName(Sec));
> +      GM.push_back({Name, Ndx});
>      }
> -    ++SectionIndex;
>    }
> -  if (!HasGroups)
> +  return Ret;
> +}
> +} // namespace
> +
> +template <class ELFT> void GNUStyle<ELFT>::printGroupSections(const ELFO *Obj) {
> +  std::vector<GroupSection> V = getGroups<ELFT>(Obj);
> +  for (const GroupSection &G : V) {
> +    OS << "\n"
> +       << G.Type << " group section [" << format_decimal(G.Index, 5) << "] `"
> +       << G.Name << "' [" << G.Signature << "] contains " << G.Members.size()
> +       << " sections:\n"
> +       << "   [Index]    Name\n";
> +    for (const GroupMember &GM : G.Members)
> +      OS << "   [" << GM.Index << "]   " << GM.Name << "\n";
> +  }
> +
> +  if (V.empty())
>      OS << "There are no section groups in this file.\n";
>  }
>  
> @@ -3489,39 +3524,22 @@
>  template <class ELFT>
>  void LLVMStyle<ELFT>::printGroupSections(const ELFO *Obj) {
>    DictScope Lists(W, "Groups");
> -  uint32_t SectionIndex = 0;
> -  bool HasGroups = false;
> -  for (const Elf_Shdr &Sec : unwrapOrError(Obj->sections())) {
> -    if (Sec.sh_type == ELF::SHT_GROUP) {
> -      HasGroups = true;
> -      const Elf_Shdr *Symtab = unwrapOrError(Obj->getSection(Sec.sh_link));
> -      StringRef StrTable = unwrapOrError(Obj->getStringTableForSymtab(*Symtab));
> -      const Elf_Sym *Sym =
> -          unwrapOrError(Obj->template getEntry<Elf_Sym>(Symtab, Sec.sh_info));
> -      auto Data = unwrapOrError(
> -          Obj->template getSectionContentsAsArray<Elf_Word>(&Sec));
> -      DictScope D(W, "Group");
> -      StringRef Name = unwrapOrError(Obj->getSectionName(&Sec));
> -      W.printNumber("Name", Name, Sec.sh_name);
> -      W.printNumber("Index", SectionIndex);
> -      W.printHex("Type", getGroupType(Data[0]), Data[0]);
> -      W.startLine() << "Signature: " << StrTable.data() + Sym->st_name << "\n";
> -      {
> -        ListScope L(W, "Section(s) in group");
> -        size_t Member = 1;
> -        while (Member < Data.size()) {
> -          auto Sec = unwrapOrError(Obj->getSection(Data[Member]));
> -          const StringRef Name = unwrapOrError(Obj->getSectionName(Sec));
> -          W.startLine() << Name << " (" << Data[Member++] << ")\n";
> -        }
> -      }
> -    }
> -    ++SectionIndex;
> +  std::vector<GroupSection> V = getGroups<ELFT>(Obj);
> +  for (const GroupSection &G : V) {
> +    DictScope D(W, "Group");
> +    W.printNumber("Name", G.Name, G.ShName);
> +    W.printNumber("Index", G.Index);
> +    W.printHex("Type", getGroupType(G.Type), G.Type);
> +    W.startLine() << "Signature: " << G.Signature << "\n";
> +
> +    ListScope L(W, "Section(s) in group");
> +    for (const GroupMember &GM : G.Members)
> +      W.startLine() << GM.Name << " (" << GM.Index << ")\n";
>    }
> -  if (!HasGroups)
> +
> +  if (V.empty())
>      W.startLine() << "There are no group sections in the file.\n";
>  }
> -
>  template <class ELFT> void LLVMStyle<ELFT>::printRelocations(const ELFO *Obj) {
>    ListScope D(W, "Relocations");
>