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Elf Writer

References:

// class .member
struct ELFWriter{
ELFObjectWriter &OWriter;
}

// parent --> child
MCObjectWriter
-> ELFObjectWriter

States:

ELFObjectWriter &OWriter
support::endian::Writer W. An adapter to write values to a stream in a particular byte order.
unsigned LastLocalSymbolIndex. This holds the symbol table index of the last local symbol.
unsigned StringTableIndex. This holds the .strtab section index.
unsigned SymbolTableIndex. This holds the .symtabl section index.
std::vector<const MCSectionELF *> SectionTable. All the sections in order. They are to be output in the section table.

Interfaces:

// llvm/lib/MC/ELFObjectWriter.cpp

  void writeHeader(const MCAssembler &Asm);

  void writeSymbol(SymbolTableWriter &Writer, uint32_t StringIndex,
                   ELFSymbolData &MSD, const MCAsmLayout &Layout);

  /// Compute the symbol table data
  ///
  /// \param Asm - The assembler.
  /// \param SectionIndexMap - Maps a section to its index.
  /// \param RevGroupMap - Maps a signature symbol to the group section.
  void computeSymbolTable(MCAssembler &Asm, const MCAsmLayout &Layout,
                          const SectionIndexMapTy &SectionIndexMap,
                          const RevGroupMapTy &RevGroupMap,
                          SectionOffsetsTy &SectionOffsets);

  MCSectionELF *createRelocationSection(MCContext &Ctx,
                                        const MCSectionELF &Sec);

  const MCSectionELF *createStringTable(MCContext &Ctx);

  void writeSectionHeader(const MCAsmLayout &Layout,
                          const SectionIndexMapTy &SectionIndexMap,
                          const SectionOffsetsTy &SectionOffsets);

  void writeSectionData(const MCAssembler &Asm, MCSection &Sec,
                        const MCAsmLayout &Layout);

  void WriteSecHdrEntry(uint32_t Name, uint32_t Type, uint64_t Flags,
                        uint64_t Address, uint64_t Offset, uint64_t Size,
                        uint32_t Link, uint32_t Info, uint64_t Alignment,
                        uint64_t EntrySize);

  void writeRelocations(const MCAssembler &Asm, const MCSectionELF &Sec);

  uint64_t writeObject(MCAssembler &Asm, const MCAsmLayout &Layout);
  void writeSection(const SectionIndexMapTy &SectionIndexMap,
                    uint32_t GroupSymbolIndex, uint64_t Offset, uint64_t Size,
                    const MCSectionELF &Section);

Elf Object Writer

References: [LLVM source code (version 11)] Inheritance/Member relation // parent --> child MCObjectWriter -> ELFObjectWriter // class .member struct ELFWriter{ ELFObjectWriter &OWriter; } States: // llvm/lib/MC/ELFObjectWriter.cpp classELFObjectWriter : public MCObjectWriter { /// The target specific ELF writer instance. std::unique_ptr<MCELFObjectTargetWriter> TargetObjectWriter; DenseMap<const MCSectionELF *, std::vector<ELFRelocationEntry>> Relocations; DenseMap<const MCSymbolELF *, const MCSymbolELF *> Renames; bool EmitAddrsigSection = false; std::vector<const MCSymbol *> AddrsigSyms; // ... friend struct ELFWriter; }; Interfaces:

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Elf Writer

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