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-rw-r--r--llvm/lib/Object/ELF.cpp263
1 files changed, 263 insertions, 0 deletions
diff --git a/llvm/lib/Object/ELF.cpp b/llvm/lib/Object/ELF.cpp
index c72a1258c1e..ef8c844a66f 100644
--- a/llvm/lib/Object/ELF.cpp
+++ b/llvm/lib/Object/ELF.cpp
@@ -215,6 +215,269 @@ StringRef llvm::object::getELFSectionTypeName(uint32_t Machine, unsigned Type) {
}
template <class ELFT>
+Expected<uint32_t>
+ELFFile<ELFT>::getSectionIndex(const Elf_Sym *Sym, Elf_Sym_Range Syms,
+ ArrayRef<Elf_Word> ShndxTable) const {
+ uint32_t Index = Sym->st_shndx;
+ if (Index == ELF::SHN_XINDEX) {
+ auto ErrorOrIndex = getExtendedSymbolTableIndex<ELFT>(
+ Sym, Syms.begin(), ShndxTable);
+ if (!ErrorOrIndex)
+ return ErrorOrIndex.takeError();
+ return *ErrorOrIndex;
+ }
+ if (Index == ELF::SHN_UNDEF || Index >= ELF::SHN_LORESERVE)
+ return 0;
+ return Index;
+}
+
+template <class ELFT>
+Expected<const typename ELFT::Shdr *>
+ELFFile<ELFT>::getSection(const Elf_Sym *Sym, const Elf_Shdr *SymTab,
+ ArrayRef<Elf_Word> ShndxTable) const {
+ auto SymsOrErr = symbols(SymTab);
+ if (!SymsOrErr)
+ return SymsOrErr.takeError();
+ return getSection(Sym, *SymsOrErr, ShndxTable);
+}
+
+template <class ELFT>
+Expected<const typename ELFT::Shdr *>
+ELFFile<ELFT>::getSection(const Elf_Sym *Sym, Elf_Sym_Range Symbols,
+ ArrayRef<Elf_Word> ShndxTable) const {
+ auto IndexOrErr = getSectionIndex(Sym, Symbols, ShndxTable);
+ if (!IndexOrErr)
+ return IndexOrErr.takeError();
+ uint32_t Index = *IndexOrErr;
+ if (Index == 0)
+ return nullptr;
+ return getSection(Index);
+}
+
+template <class ELFT>
+Expected<const typename ELFT::Sym *>
+ELFFile<ELFT>::getSymbol(const Elf_Shdr *Sec, uint32_t Index) const {
+ auto SymtabOrErr = symbols(Sec);
+ if (!SymtabOrErr)
+ return SymtabOrErr.takeError();
+ return object::getSymbol<ELFT>(*SymtabOrErr, Index);
+}
+
+template <class ELFT>
+Expected<ArrayRef<uint8_t>>
+ELFFile<ELFT>::getSectionContents(const Elf_Shdr *Sec) const {
+ return getSectionContentsAsArray<uint8_t>(Sec);
+}
+
+template <class ELFT>
+StringRef ELFFile<ELFT>::getRelocationTypeName(uint32_t Type) const {
+ return getELFRelocationTypeName(getHeader()->e_machine, Type);
+}
+
+template <class ELFT>
+void ELFFile<ELFT>::getRelocationTypeName(uint32_t Type,
+ SmallVectorImpl<char> &Result) const {
+ if (!isMipsELF64()) {
+ StringRef Name = getRelocationTypeName(Type);
+ Result.append(Name.begin(), Name.end());
+ } else {
+ // The Mips N64 ABI allows up to three operations to be specified per
+ // relocation record. Unfortunately there's no easy way to test for the
+ // presence of N64 ELFs as they have no special flag that identifies them
+ // as being N64. We can safely assume at the moment that all Mips
+ // ELFCLASS64 ELFs are N64. New Mips64 ABIs should provide enough
+ // information to disambiguate between old vs new ABIs.
+ uint8_t Type1 = (Type >> 0) & 0xFF;
+ uint8_t Type2 = (Type >> 8) & 0xFF;
+ uint8_t Type3 = (Type >> 16) & 0xFF;
+
+ // Concat all three relocation type names.
+ StringRef Name = getRelocationTypeName(Type1);
+ Result.append(Name.begin(), Name.end());
+
+ Name = getRelocationTypeName(Type2);
+ Result.append(1, '/');
+ Result.append(Name.begin(), Name.end());
+
+ Name = getRelocationTypeName(Type3);
+ Result.append(1, '/');
+ Result.append(Name.begin(), Name.end());
+ }
+}
+
+template <class ELFT>
+Expected<const typename ELFT::Sym *>
+ELFFile<ELFT>::getRelocationSymbol(const Elf_Rel *Rel,
+ const Elf_Shdr *SymTab) const {
+ uint32_t Index = Rel->getSymbol(isMips64EL());
+ if (Index == 0)
+ return nullptr;
+ return getEntry<Elf_Sym>(SymTab, Index);
+}
+
+template <class ELFT>
+Expected<StringRef>
+ELFFile<ELFT>::getSectionStringTable(Elf_Shdr_Range Sections) const {
+ uint32_t Index = getHeader()->e_shstrndx;
+ if (Index == ELF::SHN_XINDEX)
+ Index = Sections[0].sh_link;
+
+ if (!Index) // no section string table.
+ return "";
+ if (Index >= Sections.size())
+ return createError("invalid section index");
+ return getStringTable(&Sections[Index]);
+}
+
+template <class ELFT> ELFFile<ELFT>::ELFFile(StringRef Object) : Buf(Object) {}
+
+template <class ELFT>
+Expected<ELFFile<ELFT>> ELFFile<ELFT>::create(StringRef Object) {
+ if (sizeof(Elf_Ehdr) > Object.size())
+ return createError("Invalid buffer");
+ return ELFFile(Object);
+}
+
+template <class ELFT>
+Expected<typename ELFT::ShdrRange> ELFFile<ELFT>::sections() const {
+ const uintX_t SectionTableOffset = getHeader()->e_shoff;
+ if (SectionTableOffset == 0)
+ return ArrayRef<Elf_Shdr>();
+
+ if (getHeader()->e_shentsize != sizeof(Elf_Shdr))
+ return createError(
+ "invalid section header entry size (e_shentsize) in ELF header");
+
+ const uint64_t FileSize = Buf.size();
+
+ if (SectionTableOffset + sizeof(Elf_Shdr) > FileSize)
+ return createError("section header table goes past the end of the file");
+
+ // Invalid address alignment of section headers
+ if (SectionTableOffset & (alignof(Elf_Shdr) - 1))
+ return createError("invalid alignment of section headers");
+
+ const Elf_Shdr *First =
+ reinterpret_cast<const Elf_Shdr *>(base() + SectionTableOffset);
+
+ uintX_t NumSections = getHeader()->e_shnum;
+ if (NumSections == 0)
+ NumSections = First->sh_size;
+
+ if (NumSections > UINT64_MAX / sizeof(Elf_Shdr))
+ return createError("section table goes past the end of file");
+
+ const uint64_t SectionTableSize = NumSections * sizeof(Elf_Shdr);
+
+ // Section table goes past end of file!
+ if (SectionTableOffset + SectionTableSize > FileSize)
+ return createError("section table goes past the end of file");
+
+ return makeArrayRef(First, NumSections);
+}
+
+template <class ELFT>
+Expected<const typename ELFT::Shdr *>
+ELFFile<ELFT>::getSection(uint32_t Index) const {
+ auto TableOrErr = sections();
+ if (!TableOrErr)
+ return TableOrErr.takeError();
+ return object::getSection<ELFT>(*TableOrErr, Index);
+}
+
+template <class ELFT>
+Expected<StringRef>
+ELFFile<ELFT>::getStringTable(const Elf_Shdr *Section) const {
+ if (Section->sh_type != ELF::SHT_STRTAB)
+ return createError("invalid sh_type for string table, expected SHT_STRTAB");
+ auto V = getSectionContentsAsArray<char>(Section);
+ if (!V)
+ return V.takeError();
+ ArrayRef<char> Data = *V;
+ if (Data.empty())
+ return createError("empty string table");
+ if (Data.back() != '\0')
+ return createError("string table non-null terminated");
+ return StringRef(Data.begin(), Data.size());
+}
+
+template <class ELFT>
+Expected<ArrayRef<typename ELFT::Word>>
+ELFFile<ELFT>::getSHNDXTable(const Elf_Shdr &Section) const {
+ auto SectionsOrErr = sections();
+ if (!SectionsOrErr)
+ return SectionsOrErr.takeError();
+ return getSHNDXTable(Section, *SectionsOrErr);
+}
+
+template <class ELFT>
+Expected<ArrayRef<typename ELFT::Word>>
+ELFFile<ELFT>::getSHNDXTable(const Elf_Shdr &Section,
+ Elf_Shdr_Range Sections) const {
+ assert(Section.sh_type == ELF::SHT_SYMTAB_SHNDX);
+ auto VOrErr = getSectionContentsAsArray<Elf_Word>(&Section);
+ if (!VOrErr)
+ return VOrErr.takeError();
+ ArrayRef<Elf_Word> V = *VOrErr;
+ auto SymTableOrErr = object::getSection<ELFT>(Sections, Section.sh_link);
+ if (!SymTableOrErr)
+ return SymTableOrErr.takeError();
+ const Elf_Shdr &SymTable = **SymTableOrErr;
+ if (SymTable.sh_type != ELF::SHT_SYMTAB &&
+ SymTable.sh_type != ELF::SHT_DYNSYM)
+ return createError("invalid sh_type");
+ if (V.size() != (SymTable.sh_size / sizeof(Elf_Sym)))
+ return createError("invalid section contents size");
+ return V;
+}
+
+template <class ELFT>
+Expected<StringRef>
+ELFFile<ELFT>::getStringTableForSymtab(const Elf_Shdr &Sec) const {
+ auto SectionsOrErr = sections();
+ if (!SectionsOrErr)
+ return SectionsOrErr.takeError();
+ return getStringTableForSymtab(Sec, *SectionsOrErr);
+}
+
+template <class ELFT>
+Expected<StringRef>
+ELFFile<ELFT>::getStringTableForSymtab(const Elf_Shdr &Sec,
+ Elf_Shdr_Range Sections) const {
+
+ if (Sec.sh_type != ELF::SHT_SYMTAB && Sec.sh_type != ELF::SHT_DYNSYM)
+ return createError(
+ "invalid sh_type for symbol table, expected SHT_SYMTAB or SHT_DYNSYM");
+ auto SectionOrErr = object::getSection<ELFT>(Sections, Sec.sh_link);
+ if (!SectionOrErr)
+ return SectionOrErr.takeError();
+ return getStringTable(*SectionOrErr);
+}
+
+template <class ELFT>
+Expected<StringRef>
+ELFFile<ELFT>::getSectionName(const Elf_Shdr *Section) const {
+ auto SectionsOrErr = sections();
+ if (!SectionsOrErr)
+ return SectionsOrErr.takeError();
+ auto Table = getSectionStringTable(*SectionsOrErr);
+ if (!Table)
+ return Table.takeError();
+ return getSectionName(Section, *Table);
+}
+
+template <class ELFT>
+Expected<StringRef> ELFFile<ELFT>::getSectionName(const Elf_Shdr *Section,
+ StringRef DotShstrtab) const {
+ uint32_t Offset = Section->sh_name;
+ if (Offset == 0)
+ return StringRef();
+ if (Offset >= DotShstrtab.size())
+ return createError("invalid string offset");
+ return StringRef(DotShstrtab.data() + Offset);
+}
+
+template <class ELFT>
Expected<std::vector<typename ELFT::Rela>>
ELFFile<ELFT>::android_relas(const Elf_Shdr *Sec) const {
// This function reads relocations in Android's packed relocation format,
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