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-rw-r--r--lib/Object/ELF.cpp273
1 files changed, 266 insertions, 7 deletions
diff --git a/lib/Object/ELF.cpp b/lib/Object/ELF.cpp
index 5906dc5f5307..2eefb7ef13a3 100644
--- a/lib/Object/ELF.cpp
+++ b/lib/Object/ELF.cpp
@@ -125,13 +125,6 @@ StringRef llvm::object::getELFRelocationTypeName(uint32_t Machine,
break;
}
break;
- case ELF::EM_WEBASSEMBLY:
- switch (Type) {
-#include "llvm/BinaryFormat/ELFRelocs/WebAssembly.def"
- default:
- break;
- }
- break;
case ELF::EM_AMDGPU:
switch (Type) {
#include "llvm/BinaryFormat/ELFRelocs/AMDGPU.def"
@@ -154,6 +147,50 @@ StringRef llvm::object::getELFRelocationTypeName(uint32_t Machine,
#undef ELF_RELOC
+uint32_t llvm::object::getELFRelrRelocationType(uint32_t Machine) {
+ switch (Machine) {
+ case ELF::EM_X86_64:
+ return ELF::R_X86_64_RELATIVE;
+ case ELF::EM_386:
+ case ELF::EM_IAMCU:
+ return ELF::R_386_RELATIVE;
+ case ELF::EM_MIPS:
+ break;
+ case ELF::EM_AARCH64:
+ return ELF::R_AARCH64_RELATIVE;
+ case ELF::EM_ARM:
+ return ELF::R_ARM_RELATIVE;
+ case ELF::EM_ARC_COMPACT:
+ case ELF::EM_ARC_COMPACT2:
+ return ELF::R_ARC_RELATIVE;
+ case ELF::EM_AVR:
+ break;
+ case ELF::EM_HEXAGON:
+ return ELF::R_HEX_RELATIVE;
+ case ELF::EM_LANAI:
+ break;
+ case ELF::EM_PPC:
+ break;
+ case ELF::EM_PPC64:
+ return ELF::R_PPC64_RELATIVE;
+ case ELF::EM_RISCV:
+ return ELF::R_RISCV_RELATIVE;
+ case ELF::EM_S390:
+ return ELF::R_390_RELATIVE;
+ case ELF::EM_SPARC:
+ case ELF::EM_SPARC32PLUS:
+ case ELF::EM_SPARCV9:
+ return ELF::R_SPARC_RELATIVE;
+ case ELF::EM_AMDGPU:
+ break;
+ case ELF::EM_BPF:
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
StringRef llvm::object::getELFSectionTypeName(uint32_t Machine, unsigned Type) {
switch (Machine) {
case ELF::EM_ARM:
@@ -202,9 +239,14 @@ StringRef llvm::object::getELFSectionTypeName(uint32_t Machine, unsigned Type) {
STRINGIFY_ENUM_CASE(ELF, SHT_PREINIT_ARRAY);
STRINGIFY_ENUM_CASE(ELF, SHT_GROUP);
STRINGIFY_ENUM_CASE(ELF, SHT_SYMTAB_SHNDX);
+ STRINGIFY_ENUM_CASE(ELF, SHT_RELR);
STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_REL);
STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_RELA);
+ STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_RELR);
STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_ODRTAB);
+ STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_LINKER_OPTIONS);
+ STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_CALL_GRAPH_PROFILE);
+ STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_ADDRSIG);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_ATTRIBUTES);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_HASH);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_verdef);
@@ -217,6 +259,85 @@ StringRef llvm::object::getELFSectionTypeName(uint32_t Machine, unsigned Type) {
template <class ELFT>
Expected<std::vector<typename ELFT::Rela>>
+ELFFile<ELFT>::decode_relrs(Elf_Relr_Range relrs) const {
+ // This function decodes the contents of an SHT_RELR packed relocation
+ // section.
+ //
+ // Proposal for adding SHT_RELR sections to generic-abi is here:
+ // https://groups.google.com/forum/#!topic/generic-abi/bX460iggiKg
+ //
+ // The encoded sequence of Elf64_Relr entries in a SHT_RELR section looks
+ // like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
+ //
+ // i.e. start with an address, followed by any number of bitmaps. The address
+ // entry encodes 1 relocation. The subsequent bitmap entries encode up to 63
+ // relocations each, at subsequent offsets following the last address entry.
+ //
+ // The bitmap entries must have 1 in the least significant bit. The assumption
+ // here is that an address cannot have 1 in lsb. Odd addresses are not
+ // supported.
+ //
+ // Excluding the least significant bit in the bitmap, each non-zero bit in
+ // the bitmap represents a relocation to be applied to a corresponding machine
+ // word that follows the base address word. The second least significant bit
+ // represents the machine word immediately following the initial address, and
+ // each bit that follows represents the next word, in linear order. As such,
+ // a single bitmap can encode up to 31 relocations in a 32-bit object, and
+ // 63 relocations in a 64-bit object.
+ //
+ // This encoding has a couple of interesting properties:
+ // 1. Looking at any entry, it is clear whether it's an address or a bitmap:
+ // even means address, odd means bitmap.
+ // 2. Just a simple list of addresses is a valid encoding.
+
+ Elf_Rela Rela;
+ Rela.r_info = 0;
+ Rela.r_addend = 0;
+ Rela.setType(getRelrRelocationType(), false);
+ std::vector<Elf_Rela> Relocs;
+
+ // Word type: uint32_t for Elf32, and uint64_t for Elf64.
+ typedef typename ELFT::uint Word;
+
+ // Word size in number of bytes.
+ const size_t WordSize = sizeof(Word);
+
+ // Number of bits used for the relocation offsets bitmap.
+ // These many relative relocations can be encoded in a single entry.
+ const size_t NBits = 8*WordSize - 1;
+
+ Word Base = 0;
+ for (const Elf_Relr &R : relrs) {
+ Word Entry = R;
+ if ((Entry&1) == 0) {
+ // Even entry: encodes the offset for next relocation.
+ Rela.r_offset = Entry;
+ Relocs.push_back(Rela);
+ // Set base offset for subsequent bitmap entries.
+ Base = Entry + WordSize;
+ continue;
+ }
+
+ // Odd entry: encodes bitmap for relocations starting at base.
+ Word Offset = Base;
+ while (Entry != 0) {
+ Entry >>= 1;
+ if ((Entry&1) != 0) {
+ Rela.r_offset = Offset;
+ Relocs.push_back(Rela);
+ }
+ Offset += WordSize;
+ }
+
+ // Advance base offset by NBits words.
+ Base += NBits * WordSize;
+ }
+
+ return Relocs;
+}
+
+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,
// which is based on SLEB128 and delta encoding.
@@ -299,6 +420,144 @@ ELFFile<ELFT>::android_relas(const Elf_Shdr *Sec) const {
return Relocs;
}
+template <class ELFT>
+const char *ELFFile<ELFT>::getDynamicTagAsString(unsigned Arch,
+ uint64_t Type) const {
+#define DYNAMIC_STRINGIFY_ENUM(tag, value) \
+ case value: \
+ return #tag;
+
+#define DYNAMIC_TAG(n, v)
+ switch (Arch) {
+ case ELF::EM_HEXAGON:
+ switch (Type) {
+#define HEXAGON_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
+#include "llvm/BinaryFormat/DynamicTags.def"
+#undef HEXAGON_DYNAMIC_TAG
+ }
+
+ case ELF::EM_MIPS:
+ switch (Type) {
+#define MIPS_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
+#include "llvm/BinaryFormat/DynamicTags.def"
+#undef MIPS_DYNAMIC_TAG
+ }
+
+ case ELF::EM_PPC64:
+ switch (Type) {
+#define PPC64_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
+#include "llvm/BinaryFormat/DynamicTags.def"
+#undef PPC64_DYNAMIC_TAG
+ }
+ }
+#undef DYNAMIC_TAG
+ switch (Type) {
+// Now handle all dynamic tags except the architecture specific ones
+#define MIPS_DYNAMIC_TAG(name, value)
+#define HEXAGON_DYNAMIC_TAG(name, value)
+#define PPC64_DYNAMIC_TAG(name, value)
+// Also ignore marker tags such as DT_HIOS (maps to DT_VERNEEDNUM), etc.
+#define DYNAMIC_TAG_MARKER(name, value)
+#define DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
+#include "llvm/BinaryFormat/DynamicTags.def"
+#undef DYNAMIC_TAG
+#undef MIPS_DYNAMIC_TAG
+#undef HEXAGON_DYNAMIC_TAG
+#undef PPC64_DYNAMIC_TAG
+#undef DYNAMIC_TAG_MARKER
+#undef DYNAMIC_STRINGIFY_ENUM
+ default:
+ return "unknown";
+ }
+}
+
+template <class ELFT>
+const char *ELFFile<ELFT>::getDynamicTagAsString(uint64_t Type) const {
+ return getDynamicTagAsString(getHeader()->e_machine, Type);
+}
+
+template <class ELFT>
+Expected<typename ELFT::DynRange> ELFFile<ELFT>::dynamicEntries() const {
+ ArrayRef<Elf_Dyn> Dyn;
+ size_t DynSecSize = 0;
+
+ auto ProgramHeadersOrError = program_headers();
+ if (!ProgramHeadersOrError)
+ return ProgramHeadersOrError.takeError();
+
+ for (const Elf_Phdr &Phdr : *ProgramHeadersOrError) {
+ if (Phdr.p_type == ELF::PT_DYNAMIC) {
+ Dyn = makeArrayRef(
+ reinterpret_cast<const Elf_Dyn *>(base() + Phdr.p_offset),
+ Phdr.p_filesz / sizeof(Elf_Dyn));
+ DynSecSize = Phdr.p_filesz;
+ break;
+ }
+ }
+
+ // If we can't find the dynamic section in the program headers, we just fall
+ // back on the sections.
+ if (Dyn.empty()) {
+ auto SectionsOrError = sections();
+ if (!SectionsOrError)
+ return SectionsOrError.takeError();
+
+ for (const Elf_Shdr &Sec : *SectionsOrError) {
+ if (Sec.sh_type == ELF::SHT_DYNAMIC) {
+ Expected<ArrayRef<Elf_Dyn>> DynOrError =
+ getSectionContentsAsArray<Elf_Dyn>(&Sec);
+ if (!DynOrError)
+ return DynOrError.takeError();
+ Dyn = *DynOrError;
+ DynSecSize = Sec.sh_size;
+ break;
+ }
+ }
+
+ if (!Dyn.data())
+ return ArrayRef<Elf_Dyn>();
+ }
+
+ if (Dyn.empty())
+ return createError("invalid empty dynamic section");
+
+ if (DynSecSize % sizeof(Elf_Dyn) != 0)
+ return createError("malformed dynamic section");
+
+ if (Dyn.back().d_tag != ELF::DT_NULL)
+ return createError("dynamic sections must be DT_NULL terminated");
+
+ return Dyn;
+}
+
+template <class ELFT>
+Expected<const uint8_t *> ELFFile<ELFT>::toMappedAddr(uint64_t VAddr) const {
+ auto ProgramHeadersOrError = program_headers();
+ if (!ProgramHeadersOrError)
+ return ProgramHeadersOrError.takeError();
+
+ llvm::SmallVector<Elf_Phdr *, 4> LoadSegments;
+
+ for (const Elf_Phdr &Phdr : *ProgramHeadersOrError)
+ if (Phdr.p_type == ELF::PT_LOAD)
+ LoadSegments.push_back(const_cast<Elf_Phdr *>(&Phdr));
+
+ const Elf_Phdr *const *I =
+ std::upper_bound(LoadSegments.begin(), LoadSegments.end(), VAddr,
+ [](uint64_t VAddr, const Elf_Phdr_Impl<ELFT> *Phdr) {
+ return VAddr < Phdr->p_vaddr;
+ });
+
+ if (I == LoadSegments.begin())
+ return createError("Virtual address is not in any segment");
+ --I;
+ const Elf_Phdr &Phdr = **I;
+ uint64_t Delta = VAddr - Phdr.p_vaddr;
+ if (Delta >= Phdr.p_filesz)
+ return createError("Virtual address is not in any segment");
+ return base() + Phdr.p_offset + Delta;
+}
+
template class llvm::object::ELFFile<ELF32LE>;
template class llvm::object::ELFFile<ELF32BE>;
template class llvm::object::ELFFile<ELF64LE>;