2 files changed, 43 insertions, 120 deletions

diff --git a/llvm/tools/llvm-objcopy/Object.cpp b/llvm/tools/llvm-objcopy/Object.cpp
index 0c2153e4c51..b3ad7329bb6 100644
--- a/llvm/tools/llvm-objcopy/Object.cpp
+++ b/llvm/tools/llvm-objcopy/Object.cpp
@@ -77,11 +77,7 @@ void BinarySectionWriter::visit(const RelocationSection &Sec) {
 }
 
 void BinarySectionWriter::visit(const GnuDebugLinkSection &Sec) {
-  error("Cannot write '" + Sec.Name + "' out to binary");
-}
-
-void BinarySectionWriter::visit(const GroupSection &Sec) {
-  error("Cannot write '" + Sec.Name + "' out to binary");
+  error("Cannot write '.gnu_debuglink' out to binary");
 }
 
 void SectionWriter::visit(const Section &Sec) {
@@ -159,12 +155,6 @@ uint16_t Symbol::getShndx() const {
   llvm_unreachable("Symbol with invalid ShndxType encountered");
 }
 
-void SymbolTableSection::assignIndices() {
-  uint32_t Index = 0;
-  for (auto &Sym : Symbols)
-    Sym->Index = Index++;
-}
-
 void SymbolTableSection::addSymbol(StringRef Name, uint8_t Bind, uint8_t Type,
                                    SectionBase *DefinedIn, uint64_t Value,
                                    uint8_t Visibility, uint16_t Shndx,
@@ -199,7 +189,6 @@ void SymbolTableSection::removeSectionReferences(const SectionBase *Sec) {
                      [=](const SymPtr &Sym) { return Sym->DefinedIn == Sec; });
   Size -= (std::end(Symbols) - Iter) * this->EntrySize;
   Symbols.erase(Iter, std::end(Symbols));
-  assignIndices();
 }
 
 void SymbolTableSection::localize(
@@ -214,7 +203,11 @@ void SymbolTableSection::localize(
   std::stable_partition(
       std::begin(Symbols), std::end(Symbols),
       [](const SymPtr &Sym) { return Sym->Binding == STB_LOCAL; });
-  assignIndices();
+
+  // Lastly we fix the symbol indexes.
+  uint32_t Index = 0;
+  for (auto &Sym : Symbols)
+    Sym->Index = Index++;
 }
 
 void SymbolTableSection::initialize(SectionTableRef SecTable) {
@@ -281,10 +274,9 @@ template <class SymTabType>
 void RelocSectionWithSymtabBase<SymTabType>::removeSectionReferences(
     const SectionBase *Sec) {
   if (Symbols == Sec) {
-    error("Symbol table " + Symbols->Name +
-          " cannot be removed because it is "
-          "referenced by the relocation "
-          "section " +
+    error("Symbol table " + Symbols->Name + " cannot be removed because it is "
+                                            "referenced by the relocation "
+                                            "section " +
           this->Name);
   }
 }
@@ -299,9 +291,9 @@ void RelocSectionWithSymtabBase<SymTabType>::initialize(
           " is not a symbol table"));
 
   if (Info != SHN_UNDEF)
-    setSection(SecTable.getSection(Info, "Info field value " + Twine(Info) +
-                                             " in section " + Name +
-                                             " is invalid"));
+    setSection(SecTable.getSection(Info,
+                                   "Info field value " + Twine(Info) +
+                                       " in section " + Name + " is invalid"));
   else
     setSection(nullptr);
 }
@@ -355,49 +347,20 @@ void DynamicRelocationSection::accept(SectionVisitor &Visitor) const {
 
 void SectionWithStrTab::removeSectionReferences(const SectionBase *Sec) {
   if (StrTab == Sec) {
-    error("String table " + StrTab->Name +
-          " cannot be removed because it is "
-          "referenced by the section " +
+    error("String table " + StrTab->Name + " cannot be removed because it is "
+                                           "referenced by the section " +
           this->Name);
   }
 }
 
-void GroupSection::initialize(SectionTableRef SecTable) {
-  SymTab = SecTable.getSectionOfType<SymbolTableSection>(
-      Link,
-      "Link field value " + Twine(Link) + " in section " + Name + " is invalid",
-      "Link field value " + Twine(Link) + " in section " + Name +
-          " is not a symbol table");
-  Sym = SymTab->getSymbolByIndex(Info);
-  if (!Sym)
-    error("Info field value " + Twine(Info) + " in section " + Name +
-          " is not a valid symbol index");
-  if (Contents.size() % sizeof(ELF::Elf32_Word) || Contents.empty())
-    error("The content of the section " + Name + " is malformed");
-  const ELF::Elf32_Word *Word =
-      reinterpret_cast<const ELF::Elf32_Word *>(Contents.data());
-  const ELF::Elf32_Word *End = Word + Contents.size() / sizeof(ELF::Elf32_Word);
-  FlagWord = *Word++;
-  for (; Word != End; ++Word) {
-    GroupMembers.push_back(
-        SecTable.getSection(*Word, "Group member index " + Twine(*Word) +
-                                       " in section " + Name + " is invalid"));
-  }
-}
-
-void GroupSection::finalize() {
-  this->Info = Sym->Index;
-  this->Link = SymTab->Index;
-}
-
 bool SectionWithStrTab::classof(const SectionBase *S) {
   return isa<DynamicSymbolTableSection>(S) || isa<DynamicSection>(S);
 }
 
 void SectionWithStrTab::initialize(SectionTableRef SecTable) {
-  auto StrTab =
-      SecTable.getSection(Link, "Link field value " + Twine(Link) +
-                                    " in section " + Name + " is invalid");
+  auto StrTab = SecTable.getSection(Link,
+                                    "Link field value " + Twine(Link) +
+                                        " in section " + Name + " is invalid");
   if (StrTab->Type != SHT_STRTAB) {
     error("Link field value " + Twine(Link) + " in section " + Name +
           " is not a string table");
@@ -453,19 +416,6 @@ void GnuDebugLinkSection::accept(SectionVisitor &Visitor) const {
   Visitor.visit(*this);
 }
 
-template <class ELFT>
-void ELFSectionWriter<ELFT>::visit(const GroupSection &Sec) {
-  ELF::Elf32_Word *Buf =
-      reinterpret_cast<ELF::Elf32_Word *>(Out.getBufferStart() + Sec.Offset);
-  *Buf++ = Sec.FlagWord;
-  for (const auto *S : Sec.GroupMembers)
-    *Buf++ = S->Index;
-}
-
-void GroupSection::accept(SectionVisitor &Visitor) const {
-  Visitor.visit(*this);
-}
-
 // Returns true IFF a section is wholly inside the range of a segment
 static bool sectionWithinSegment(const SectionBase &Section,
                                  const Segment &Segment) {
@@ -505,7 +455,8 @@ static bool compareSegmentsByPAddr(const Segment *A, const Segment *B) {
   return A->Index < B->Index;
 }
 
-template <class ELFT> void ELFBuilder<ELFT>::setParentSegment(Segment &Child) {
+template <class ELFT>
+void ELFBuilder<ELFT>::setParentSegment(Segment &Child) {
   for (auto &Parent : Obj.segments()) {
     // Every segment will overlap with itself but we don't want a segment to
     // be it's own parent so we avoid that situation.
@@ -571,7 +522,7 @@ template <class ELFT> void ELFBuilder<ELFT>::readProgramHeaders() {
   PrHdr.OriginalOffset = PrHdr.Offset = PrHdr.VAddr = Ehdr.e_phoff;
   PrHdr.PAddr = 0;
   PrHdr.FileSize = PrHdr.MemSize = Ehdr.e_phentsize * Ehdr.e_phnum;
-  // The spec requires us to naturally align all the fields.
+  // The spec requires us to naturally align all the fields. 
   PrHdr.Align = sizeof(Elf_Addr);
   PrHdr.Index = Index++;
 
@@ -601,9 +552,9 @@ void ELFBuilder<ELFT>::initSymbolTable(SymbolTableSection *SymTab) {
       }
     } else if (Sym.st_shndx != SHN_UNDEF) {
       DefSection = Obj.sections().getSection(
-          Sym.st_shndx, "Symbol '" + Name +
-                            "' is defined in invalid section with index " +
-                            Twine(Sym.st_shndx));
+          Sym.st_shndx,
+          "Symbol '" + Name + "' is defined in invalid section with index " +
+              Twine(Sym.st_shndx));
     }
 
     SymTab->addSymbol(Name, Sym.getBinding(), Sym.getType(), DefSection,
@@ -672,9 +623,6 @@ SectionBase &ELFBuilder<ELFT>::makeSection(const Elf_Shdr &Shdr) {
     // Because of this we don't need to mess with the hash tables either.
     Data = unwrapOrError(ElfFile.getSectionContents(&Shdr));
     return Obj.addSection<Section>(Data);
-  case SHT_GROUP:
-    Data = unwrapOrError(ElfFile.getSectionContents(&Shdr));
-    return Obj.addSection<GroupSection>(Data);
   case SHT_DYNSYM:
     Data = unwrapOrError(ElfFile.getSectionContents(&Shdr));
     return Obj.addSection<DynamicSymbolTableSection>(Data);
diff --git a/llvm/tools/llvm-objcopy/Object.h b/llvm/tools/llvm-objcopy/Object.h
index 36bd65b8cf2..27beafc0ce6 100644
--- a/llvm/tools/llvm-objcopy/Object.h
+++ b/llvm/tools/llvm-objcopy/Object.h
@@ -35,17 +35,17 @@ class SymbolTableSection;
 class RelocationSection;
 class DynamicRelocationSection;
 class GnuDebugLinkSection;
-class GroupSection;
 class Segment;
 class Object;
 
 class SectionTableRef {
+private:
   MutableArrayRef<std::unique_ptr<SectionBase>> Sections;
 
 public:
   using iterator = pointee_iterator<std::unique_ptr<SectionBase> *>;
 
-  explicit SectionTableRef(MutableArrayRef<std::unique_ptr<SectionBase>> Secs)
+  SectionTableRef(MutableArrayRef<std::unique_ptr<SectionBase>> Secs)
       : Sections(Secs) {}
   SectionTableRef(const SectionTableRef &) = default;
 
@@ -71,7 +71,6 @@ public:
   virtual void visit(const RelocationSection &Sec) = 0;
   virtual void visit(const DynamicRelocationSection &Sec) = 0;
   virtual void visit(const GnuDebugLinkSection &Sec) = 0;
-  virtual void visit(const GroupSection &Sec) = 0;
 };
 
 class SectionWriter : public SectionVisitor {
@@ -88,7 +87,6 @@ public:
   virtual void visit(const SymbolTableSection &Sec) override = 0;
   virtual void visit(const RelocationSection &Sec) override = 0;
   virtual void visit(const GnuDebugLinkSection &Sec) override = 0;
-  virtual void visit(const GroupSection &Sec) override = 0;
 
   SectionWriter(FileOutputBuffer &Buf) : Out(Buf) {}
 };
@@ -104,7 +102,6 @@ public:
   void visit(const SymbolTableSection &Sec) override;
   void visit(const RelocationSection &Sec) override;
   void visit(const GnuDebugLinkSection &Sec) override;
-  void visit(const GroupSection &Sec) override;
 
   ELFSectionWriter(FileOutputBuffer &Buf) : SectionWriter(Buf) {}
 };
@@ -120,8 +117,6 @@ public:
   void visit(const SymbolTableSection &Sec) override;
   void visit(const RelocationSection &Sec) override;
   void visit(const GnuDebugLinkSection &Sec) override;
-  void visit(const GroupSection &Sec) override;
-
   BinarySectionWriter(FileOutputBuffer &Buf) : SectionWriter(Buf) {}
 };
 
@@ -242,7 +237,7 @@ public:
   uint64_t OriginalOffset;
   Segment *ParentSegment = nullptr;
 
-  explicit Segment(ArrayRef<uint8_t> Data) : Contents(Data) {}
+  Segment(ArrayRef<uint8_t> Data) : Contents(Data) {}
   Segment() {}
 
   const SectionBase *firstSection() const {
@@ -258,10 +253,11 @@ public:
 class Section : public SectionBase {
   MAKE_SEC_WRITER_FRIEND
 
+private:
   ArrayRef<uint8_t> Contents;
 
 public:
-  explicit Section(ArrayRef<uint8_t> Data) : Contents(Data) {}
+  Section(ArrayRef<uint8_t> Data) : Contents(Data) {}
 
   void accept(SectionVisitor &Visitor) const override;
 };
@@ -269,6 +265,7 @@ public:
 class OwnedDataSection : public SectionBase {
   MAKE_SEC_WRITER_FRIEND
 
+private:
   std::vector<uint8_t> Data;
 
 public:
@@ -294,6 +291,7 @@ public:
 class StringTableSection : public SectionBase {
   MAKE_SEC_WRITER_FRIEND
 
+private:
   StringTableBuilder StrTabBuilder;
 
 public:
@@ -346,7 +344,6 @@ class SymbolTableSection : public SectionBase {
   MAKE_SEC_WRITER_FRIEND
 
   void setStrTab(StringTableSection *StrTab) { SymbolNames = StrTab; }
-  void assignIndices();
 
 protected:
   std::vector<std::unique_ptr<Symbol>> Symbols;
@@ -405,6 +402,7 @@ public:
 // that code between the two symbol table types.
 template <class SymTabType>
 class RelocSectionWithSymtabBase : public RelocationSectionBase {
+private:
   SymTabType *Symbols = nullptr;
   void setSymTab(SymTabType *SymTab) { Symbols = SymTab; }
 
@@ -421,6 +419,7 @@ class RelocationSection
     : public RelocSectionWithSymtabBase<SymbolTableSection> {
   MAKE_SEC_WRITER_FRIEND
 
+private:
   std::vector<Relocation> Relocations;
 
 public:
@@ -434,37 +433,14 @@ public:
   }
 };
 
-// TODO: The way stripping and groups interact is complicated
-// and still needs to be worked on.
-
-class GroupSection : public SectionBase {
-  MAKE_SEC_WRITER_FRIEND
-  // TODO: Contents is present in several classes of the hierarchy.
-  // This needs to be refactored to avoid duplication.
-  ArrayRef<uint8_t> Contents;
-  ELF::Elf32_Word FlagWord;
-  SmallVector<SectionBase *, 3> GroupMembers;
-  const SymbolTableSection *SymTab = nullptr;
-  const Symbol *Sym = nullptr;
-
-public:
-  explicit GroupSection(ArrayRef<uint8_t> Data) : Contents(Data) {}
-
-  void initialize(SectionTableRef SecTable) override;
-  void accept(SectionVisitor &) const override;
-  void finalize() override;
-
-  static bool classof(const SectionBase *S) {
-    return S->Type == ELF::SHT_GROUP;
-  }
-};
-
 class SectionWithStrTab : public Section {
+private:
   const SectionBase *StrTab = nullptr;
-  void setStrTab(const SectionBase *StringTable) { StrTab = StringTable; }
 
 public:
-  explicit SectionWithStrTab(ArrayRef<uint8_t> Data) : Section(Data) {}
+  SectionWithStrTab(ArrayRef<uint8_t> Data) : Section(Data) {}
+
+  void setStrTab(const SectionBase *StringTable) { StrTab = StringTable; }
   void removeSectionReferences(const SectionBase *Sec) override;
   void initialize(SectionTableRef SecTable) override;
   void finalize() override;
@@ -473,8 +449,7 @@ public:
 
 class DynamicSymbolTableSection : public SectionWithStrTab {
 public:
-  explicit DynamicSymbolTableSection(ArrayRef<uint8_t> Data)
-      : SectionWithStrTab(Data) {}
+  DynamicSymbolTableSection(ArrayRef<uint8_t> Data) : SectionWithStrTab(Data) {}
 
   static bool classof(const SectionBase *S) {
     return S->Type == ELF::SHT_DYNSYM;
@@ -483,7 +458,7 @@ public:
 
 class DynamicSection : public SectionWithStrTab {
 public:
-  explicit DynamicSection(ArrayRef<uint8_t> Data) : SectionWithStrTab(Data) {}
+  DynamicSection(ArrayRef<uint8_t> Data) : SectionWithStrTab(Data) {}
 
   static bool classof(const SectionBase *S) {
     return S->Type == ELF::SHT_DYNAMIC;
@@ -498,7 +473,7 @@ private:
   ArrayRef<uint8_t> Contents;
 
 public:
-  explicit DynamicRelocationSection(ArrayRef<uint8_t> Data) : Contents(Data) {}
+  DynamicRelocationSection(ArrayRef<uint8_t> Data) : Contents(Data) {}
 
   void accept(SectionVisitor &) const override;
 
@@ -513,6 +488,7 @@ class GnuDebugLinkSection : public SectionBase {
   MAKE_SEC_WRITER_FRIEND
 
 private:
+
   StringRef FileName;
   uint32_t CRC32;
 
@@ -520,7 +496,7 @@ private:
 
 public:
   // If we add this section from an external source we can use this ctor.
-  explicit GnuDebugLinkSection(StringRef File);
+  GnuDebugLinkSection(StringRef File);
   void accept(SectionVisitor &Visitor) const override;
 };
 
@@ -530,10 +506,10 @@ public:
   virtual std::unique_ptr<Object> create() const = 0;
 };
 
+using object::OwningBinary;
 using object::Binary;
 using object::ELFFile;
 using object::ELFObjectFile;
-using object::OwningBinary;
 
 template <class ELFT> class ELFBuilder {
 private:
@@ -606,8 +582,7 @@ public:
   StringTableSection *SectionNames = nullptr;
   SymbolTableSection *SymbolTable = nullptr;
 
-  explicit Object(std::shared_ptr<MemoryBuffer> Data)
-      : OwnedData(std::move(Data)) {}
+  Object(std::shared_ptr<MemoryBuffer> Data) : OwnedData(Data) {}
   virtual ~Object() = default;
 
   void sortSections();