[llvm-commits] [llvm] r123896 - in /llvm/trunk: include/llvm/Support/ELF.h lib/Object/CMakeLists.txt lib/Object/ELFObjectFile.cpp lib/Object/ObjectFile.cpp
Michael J. Spencer
bigcheesegs at gmail.com
Wed Jan 19 22:38:47 PST 2011
Author: mspencer
Date: Thu Jan 20 00:38:47 2011
New Revision: 123896
URL: http://llvm.org/viewvc/llvm-project?rev=123896&view=rev
Log:
Object: Add ELF support.
Added:
llvm/trunk/lib/Object/ELFObjectFile.cpp
Modified:
llvm/trunk/include/llvm/Support/ELF.h
llvm/trunk/lib/Object/CMakeLists.txt
llvm/trunk/lib/Object/ObjectFile.cpp
Modified: llvm/trunk/include/llvm/Support/ELF.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/ELF.h?rev=123896&r1=123895&r2=123896&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/ELF.h (original)
+++ llvm/trunk/include/llvm/Support/ELF.h Thu Jan 20 00:38:47 2011
@@ -146,6 +146,7 @@
// Object file classes.
enum {
+ ELFCLASSNONE = 0,
ELFCLASS32 = 1, // 32-bit object file
ELFCLASS64 = 2 // 64-bit object file
};
@@ -510,6 +511,8 @@
SHF_WRITE = 0x1, // Section data should be writable during execution.
SHF_ALLOC = 0x2, // Section occupies memory during program execution.
SHF_EXECINSTR = 0x4, // Section contains executable machine instructions.
+ SHF_MERGE = 0x10, // The data in this section may be merged.
+ SHF_STRINGS = 0x20, // The data in this section is null-terminated strings.
SHF_MASKPROC = 0xf0000000 // Bits indicating processor-specific flags.
};
Modified: llvm/trunk/lib/Object/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/CMakeLists.txt?rev=123896&r1=123895&r2=123896&view=diff
==============================================================================
--- llvm/trunk/lib/Object/CMakeLists.txt (original)
+++ llvm/trunk/lib/Object/CMakeLists.txt Thu Jan 20 00:38:47 2011
@@ -2,4 +2,5 @@
MachOObject.cpp
ObjectFile.cpp
COFFObjectFile.cpp
+ ELFObjectFile.cpp
)
Added: llvm/trunk/lib/Object/ELFObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/ELFObjectFile.cpp?rev=123896&view=auto
==============================================================================
--- llvm/trunk/lib/Object/ELFObjectFile.cpp (added)
+++ llvm/trunk/lib/Object/ELFObjectFile.cpp Thu Jan 20 00:38:47 2011
@@ -0,0 +1,706 @@
+//===- ELFObjectFile.cpp - ELF object file implementation -------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the ELFObjectFile class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <limits>
+#include <utility>
+
+using namespace llvm;
+using namespace object;
+
+// Templates to choose Elf_Addr and Elf_Off depending on is64Bits.
+namespace {
+template<support::endianness target_endianness>
+struct ELFDataTypeTypedefHelperCommon {
+ typedef support::detail::packed_endian_specific_integral
+ <uint16_t, target_endianness, support::aligned> Elf_Half;
+ typedef support::detail::packed_endian_specific_integral
+ <uint32_t, target_endianness, support::aligned> Elf_Word;
+ typedef support::detail::packed_endian_specific_integral
+ <int32_t, target_endianness, support::aligned> Elf_Sword;
+ typedef support::detail::packed_endian_specific_integral
+ <uint64_t, target_endianness, support::aligned> Elf_Xword;
+ typedef support::detail::packed_endian_specific_integral
+ <int64_t, target_endianness, support::aligned> Elf_Sxword;
+};
+}
+
+namespace {
+template<support::endianness target_endianness, bool is64Bits>
+struct ELFDataTypeTypedefHelper;
+
+/// ELF 32bit types.
+template<support::endianness target_endianness>
+struct ELFDataTypeTypedefHelper<target_endianness, false>
+ : ELFDataTypeTypedefHelperCommon<target_endianness> {
+ typedef support::detail::packed_endian_specific_integral
+ <uint32_t, target_endianness, support::aligned> Elf_Addr;
+ typedef support::detail::packed_endian_specific_integral
+ <uint32_t, target_endianness, support::aligned> Elf_Off;
+};
+
+/// ELF 64bit types.
+template<support::endianness target_endianness>
+struct ELFDataTypeTypedefHelper<target_endianness, true>
+ : ELFDataTypeTypedefHelperCommon<target_endianness>{
+ typedef support::detail::packed_endian_specific_integral
+ <uint64_t, target_endianness, support::aligned> Elf_Addr;
+ typedef support::detail::packed_endian_specific_integral
+ <uint64_t, target_endianness, support::aligned> Elf_Off;
+};
+}
+
+// I really don't like doing this, but the alternative is copypasta.
+#define LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits) \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Addr Elf_Addr; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Off Elf_Off; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Half Elf_Half; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Word Elf_Word; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Sword Elf_Sword; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Xword Elf_Xword; \
+typedef typename \
+ ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Sxword Elf_Sxword;
+
+ // Section header.
+namespace {
+template<support::endianness target_endianness, bool is64Bits>
+struct Elf_Shdr_Base;
+
+template<support::endianness target_endianness>
+struct Elf_Shdr_Base<target_endianness, false> {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, false)
+ Elf_Word sh_name; // Section name (index into string table)
+ Elf_Word sh_type; // Section type (SHT_*)
+ Elf_Word sh_flags; // Section flags (SHF_*)
+ Elf_Addr sh_addr; // Address where section is to be loaded
+ Elf_Off sh_offset; // File offset of section data, in bytes
+ Elf_Word sh_size; // Size of section, in bytes
+ Elf_Word sh_link; // Section type-specific header table index link
+ Elf_Word sh_info; // Section type-specific extra information
+ Elf_Word sh_addralign;// Section address alignment
+ Elf_Word sh_entsize; // Size of records contained within the section
+};
+
+template<support::endianness target_endianness>
+struct Elf_Shdr_Base<target_endianness, true> {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, true)
+ Elf_Word sh_name; // Section name (index into string table)
+ Elf_Word sh_type; // Section type (SHT_*)
+ Elf_Xword sh_flags; // Section flags (SHF_*)
+ Elf_Addr sh_addr; // Address where section is to be loaded
+ Elf_Off sh_offset; // File offset of section data, in bytes
+ Elf_Xword sh_size; // Size of section, in bytes
+ Elf_Word sh_link; // Section type-specific header table index link
+ Elf_Word sh_info; // Section type-specific extra information
+ Elf_Xword sh_addralign;// Section address alignment
+ Elf_Xword sh_entsize; // Size of records contained within the section
+};
+
+template<support::endianness target_endianness, bool is64Bits>
+struct Elf_Shdr_Impl : Elf_Shdr_Base<target_endianness, is64Bits> {
+ using Elf_Shdr_Base<target_endianness, is64Bits>::sh_entsize;
+ using Elf_Shdr_Base<target_endianness, is64Bits>::sh_size;
+
+ /// @brief Get the number of entities this section contains if it has any.
+ unsigned getEntityCount() const {
+ if (sh_entsize == 0)
+ return 0;
+ else
+ return sh_size / sh_entsize;
+ }
+};
+}
+
+namespace {
+template<support::endianness target_endianness, bool is64Bits>
+struct Elf_Sym_Base;
+
+template<support::endianness target_endianness>
+struct Elf_Sym_Base<target_endianness, false> {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, false)
+ Elf_Word st_name; // Symbol name (index into string table)
+ Elf_Addr st_value; // Value or address associated with the symbol
+ Elf_Word st_size; // Size of the symbol
+ unsigned char st_info; // Symbol's type and binding attributes
+ unsigned char st_other; // Must be zero; reserved
+ Elf_Half st_shndx; // Which section (header table index) it's defined in
+};
+
+template<support::endianness target_endianness>
+struct Elf_Sym_Base<target_endianness, true> {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, true)
+ Elf_Word st_name; // Symbol name (index into string table)
+ unsigned char st_info; // Symbol's type and binding attributes
+ unsigned char st_other; // Must be zero; reserved
+ Elf_Half st_shndx; // Which section (header table index) it's defined in
+ Elf_Addr st_value; // Value or address associated with the symbol
+ Elf_Xword st_size; // Size of the symbol
+};
+
+template<support::endianness target_endianness, bool is64Bits>
+struct Elf_Sym_Impl : Elf_Sym_Base<target_endianness, is64Bits> {
+ using Elf_Sym_Base<target_endianness, is64Bits>::st_info;
+
+ // These accessors and mutators correspond to the ELF32_ST_BIND,
+ // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification:
+ unsigned char getBinding() const { return st_info >> 4; }
+ unsigned char getType() const { return st_info & 0x0f; }
+ void setBinding(unsigned char b) { setBindingAndType(b, getType()); }
+ void setType(unsigned char t) { setBindingAndType(getBinding(), t); }
+ void setBindingAndType(unsigned char b, unsigned char t) {
+ st_info = (b << 4) + (t & 0x0f);
+ }
+};
+}
+
+namespace {
+struct ELFDataRefImpl {
+ uint32_t SymbolIndex;
+ uint16_t SymbolTableSectionIndex;
+ uint16_t Unused;
+};
+}
+
+namespace {
+template<support::endianness target_endianness, bool is64Bits>
+class ELFObjectFile : public ObjectFile {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits)
+
+ typedef Elf_Shdr_Impl<target_endianness, is64Bits> Elf_Shdr;
+ typedef Elf_Sym_Impl<target_endianness, is64Bits> Elf_Sym;
+
+ struct Elf_Ehdr {
+ unsigned char e_ident[ELF::EI_NIDENT]; // ELF Identification bytes
+ Elf_Half e_type; // Type of file (see ET_*)
+ Elf_Half e_machine; // Required architecture for this file (see EM_*)
+ Elf_Word e_version; // Must be equal to 1
+ Elf_Addr e_entry; // Address to jump to in order to start program
+ Elf_Off e_phoff; // Program header table's file offset, in bytes
+ Elf_Off e_shoff; // Section header table's file offset, in bytes
+ Elf_Word e_flags; // Processor-specific flags
+ Elf_Half e_ehsize; // Size of ELF header, in bytes
+ Elf_Half e_phentsize;// Size of an entry in the program header table
+ Elf_Half e_phnum; // Number of entries in the program header table
+ Elf_Half e_shentsize;// Size of an entry in the section header table
+ Elf_Half e_shnum; // Number of entries in the section header table
+ Elf_Half e_shstrndx; // Section header table index of section name
+ // string table
+ bool checkMagic() const {
+ return (memcmp(e_ident, ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0;
+ }
+ unsigned char getFileClass() const { return e_ident[ELF::EI_CLASS]; }
+ unsigned char getDataEncoding() const { return e_ident[ELF::EI_DATA]; }
+ };
+
+ typedef SmallVector<const Elf_Shdr*, 1> SymbolTableSections_t;
+
+ const Elf_Ehdr *Header;
+ const Elf_Shdr *SectionHeaderTable;
+ const Elf_Shdr *dot_shstrtab_sec; // Section header string table.
+ const Elf_Shdr *dot_strtab_sec; // Symbol header string table.
+ SymbolTableSections_t SymbolTableSections;
+
+ void validateSymbol(DataRefImpl Symb) const;
+ const Elf_Sym *getSymbol(DataRefImpl Symb) const;
+ const Elf_Shdr *getSection(DataRefImpl index) const;
+ const Elf_Shdr *getSection(uint16_t index) const;
+ const char *getString(uint16_t section, uint32_t offset) const;
+ const char *getString(const Elf_Shdr *section, uint32_t offset) const;
+
+protected:
+ virtual SymbolRef getSymbolNext(DataRefImpl Symb) const;
+ virtual StringRef getSymbolName(DataRefImpl Symb) const;
+ virtual uint64_t getSymbolAddress(DataRefImpl Symb) const;
+ virtual uint64_t getSymbolSize(DataRefImpl Symb) const;
+ virtual char getSymbolNMTypeChar(DataRefImpl Symb) const;
+ virtual bool isSymbolInternal(DataRefImpl Symb) const;
+
+ virtual SectionRef getSectionNext(DataRefImpl Sec) const;
+ virtual StringRef getSectionName(DataRefImpl Sec) const;
+ virtual uint64_t getSectionAddress(DataRefImpl Sec) const;
+ virtual uint64_t getSectionSize(DataRefImpl Sec) const;
+ virtual StringRef getSectionContents(DataRefImpl Sec) const;
+ virtual bool isSectionText(DataRefImpl Sec) const;
+
+public:
+ ELFObjectFile(MemoryBuffer *Object);
+ virtual symbol_iterator begin_symbols() const;
+ virtual symbol_iterator end_symbols() const;
+ virtual section_iterator begin_sections() const;
+ virtual section_iterator end_sections() const;
+
+ virtual uint8_t getBytesInAddress() const;
+ virtual StringRef getFileFormatName() const;
+ virtual unsigned getArch() const;
+};
+} // end namespace
+
+template<support::endianness target_endianness, bool is64Bits>
+void ELFObjectFile<target_endianness, is64Bits>
+ ::validateSymbol(DataRefImpl Symb) const {
+ const ELFDataRefImpl SymbolData = *reinterpret_cast<ELFDataRefImpl *>(&Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+ const Elf_Shdr *SymbolTableSection =
+ SymbolTableSections[SymbolData.SymbolTableSectionIndex];
+ // FIXME: We really need to do proper error handling in the case of an invalid
+ // input file. Because we don't use exceptions, I think we'll just pass
+ // an error object around.
+ if (!( symb
+ && SymbolTableSection
+ && symb >= (const Elf_Sym*)(base
+ + SymbolTableSection->sh_offset)
+ && symb < (const Elf_Sym*)(base
+ + SymbolTableSection->sh_offset
+ + SymbolTableSection->sh_size)))
+ // FIXME: Proper error handling.
+ report_fatal_error("Symb must point to a valid symbol!");
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+SymbolRef ELFObjectFile<target_endianness, is64Bits>
+ ::getSymbolNext(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ ELFDataRefImpl &SymbolData = *reinterpret_cast<ELFDataRefImpl *>(&Symb);
+ const Elf_Shdr *SymbolTableSection =
+ SymbolTableSections[SymbolData.SymbolTableSectionIndex];
+
+ ++SymbolData.SymbolIndex;
+ // Check to see if we are at the end of this symbol table.
+ if (SymbolData.SymbolIndex >= SymbolTableSection->getEntityCount()) {
+ // We are at the end. If there are other symbol tables, jump to them.
+ ++SymbolData.SymbolTableSectionIndex;
+ SymbolData.SymbolIndex = 1; // The 0th symbol in ELF is fake.
+ // Otherwise return the terminator.
+ if (SymbolData.SymbolTableSectionIndex >= SymbolTableSections.size()) {
+ SymbolData.SymbolIndex = std::numeric_limits<uint32_t>::max();
+ SymbolData.SymbolTableSectionIndex = std::numeric_limits<uint32_t>::max();
+ }
+ }
+
+ return SymbolRef(Symb, this);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+StringRef ELFObjectFile<target_endianness, is64Bits>
+ ::getSymbolName(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+ if (symb->st_name == 0) {
+ const Elf_Shdr *section = getSection(symb->st_shndx);
+ if (!section)
+ return "";
+ return getString(dot_shstrtab_sec, section->sh_name);
+ }
+
+ // Use the default symbol table name section.
+ return getString(dot_strtab_sec, symb->st_name);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+uint64_t ELFObjectFile<target_endianness, is64Bits>
+ ::getSymbolAddress(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+ const Elf_Shdr *Section;
+ switch (symb->st_shndx) {
+ case ELF::SHN_COMMON:
+ // Undefined symbols have no address yet.
+ case ELF::SHN_UNDEF: return UnknownAddressOrSize;
+ case ELF::SHN_ABS: return symb->st_value;
+ default: Section = getSection(symb->st_shndx);
+ }
+
+ switch (symb->getType()) {
+ case ELF::STT_SECTION: return Section ? Section->sh_addr
+ : UnknownAddressOrSize;
+ case ELF::STT_FUNC:
+ case ELF::STT_OBJECT:
+ case ELF::STT_NOTYPE:
+ return symb->st_value;
+ default: return UnknownAddressOrSize;
+ }
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+uint64_t ELFObjectFile<target_endianness, is64Bits>
+ ::getSymbolSize(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+ if (symb->st_size == 0)
+ return UnknownAddressOrSize;
+ return symb->st_size;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+char ELFObjectFile<target_endianness, is64Bits>
+ ::getSymbolNMTypeChar(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+ const Elf_Shdr *Section = getSection(symb->st_shndx);
+
+ char ret = '?';
+
+ if (Section) {
+ switch (Section->sh_type) {
+ case ELF::SHT_PROGBITS:
+ case ELF::SHT_DYNAMIC:
+ switch (Section->sh_flags) {
+ case (ELF::SHF_ALLOC | ELF::SHF_EXECINSTR):
+ ret = 't'; break;
+ case (ELF::SHF_ALLOC | ELF::SHF_WRITE):
+ ret = 'd'; break;
+ case ELF::SHF_ALLOC:
+ case (ELF::SHF_ALLOC | ELF::SHF_MERGE):
+ case (ELF::SHF_ALLOC | ELF::SHF_MERGE | ELF::SHF_STRINGS):
+ ret = 'r'; break;
+ }
+ break;
+ case ELF::SHT_NOBITS: ret = 'b';
+ }
+ }
+
+ switch (symb->st_shndx) {
+ case ELF::SHN_UNDEF:
+ if (ret == '?')
+ ret = 'U';
+ break;
+ case ELF::SHN_ABS: ret = 'a'; break;
+ case ELF::SHN_COMMON: ret = 'c'; break;
+ }
+
+ switch (symb->getBinding()) {
+ case ELF::STB_GLOBAL: ret = ::toupper(ret); break;
+ case ELF::STB_WEAK:
+ if (symb->st_shndx == ELF::SHN_UNDEF)
+ ret = 'w';
+ else
+ if (symb->getType() == ELF::STT_OBJECT)
+ ret = 'V';
+ else
+ ret = 'W';
+ }
+
+ if (ret == '?' && symb->getType() == ELF::STT_SECTION)
+ return StringSwitch<char>(getSymbolName(Symb))
+ .StartsWith(".debug", 'N')
+ .StartsWith(".note", 'n');
+
+ return ret;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+bool ELFObjectFile<target_endianness, is64Bits>
+ ::isSymbolInternal(DataRefImpl Symb) const {
+ validateSymbol(Symb);
+ const Elf_Sym *symb = getSymbol(Symb);
+
+ if ( symb->getType() == ELF::STT_FILE
+ || symb->getType() == ELF::STT_SECTION)
+ return true;
+ return false;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+SectionRef ELFObjectFile<target_endianness, is64Bits>
+ ::getSectionNext(DataRefImpl Sec) const {
+ const uint8_t *sec = *reinterpret_cast<const uint8_t **>(&Sec);
+ sec += Header->e_shentsize;
+ return SectionRef(DataRefImpl(sec), this);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+StringRef ELFObjectFile<target_endianness, is64Bits>
+ ::getSectionName(DataRefImpl Sec) const {
+ const Elf_Shdr *sec =
+ *reinterpret_cast<const Elf_Shdr **>(&Sec);
+ return StringRef(getString(dot_shstrtab_sec, sec->sh_name));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+uint64_t ELFObjectFile<target_endianness, is64Bits>
+ ::getSectionAddress(DataRefImpl Sec) const {
+ const Elf_Shdr *sec =
+ *reinterpret_cast<const Elf_Shdr **>(&Sec);
+ return sec->sh_addr;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+uint64_t ELFObjectFile<target_endianness, is64Bits>
+ ::getSectionSize(DataRefImpl Sec) const {
+ const Elf_Shdr *sec =
+ *reinterpret_cast<const Elf_Shdr **>(&Sec);
+ return sec->sh_size;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+StringRef ELFObjectFile<target_endianness, is64Bits>
+ ::getSectionContents(DataRefImpl Sec) const {
+ const Elf_Shdr *sec =
+ *reinterpret_cast<const Elf_Shdr **>(&Sec);
+ const char *start = (char*)base + sec->sh_offset;
+ return StringRef(start, sec->sh_size);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+bool ELFObjectFile<target_endianness, is64Bits>
+ ::isSectionText(DataRefImpl Sec) const {
+ const Elf_Shdr *sec =
+ *reinterpret_cast<const Elf_Shdr **>(&Sec);
+ if (sec->sh_flags & ELF::SHF_EXECINSTR)
+ return true;
+ return false;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+ELFObjectFile<target_endianness, is64Bits>::ELFObjectFile(MemoryBuffer *Object)
+ : ObjectFile(Object)
+ , SectionHeaderTable(0)
+ , dot_shstrtab_sec(0)
+ , dot_strtab_sec(0) {
+ Header = reinterpret_cast<const Elf_Ehdr *>(base);
+
+ if (Header->e_shoff == 0)
+ return;
+
+ SectionHeaderTable =
+ reinterpret_cast<const Elf_Shdr *>(base + Header->e_shoff);
+ uint32_t SectionTableSize = Header->e_shnum * Header->e_shentsize;
+ if (!( (const uint8_t *)SectionHeaderTable + SectionTableSize
+ <= base + MapFile->getBufferSize()))
+ // FIXME: Proper error handling.
+ report_fatal_error("Section table goes past end of file!");
+
+
+ // To find the symbol tables we walk the section table to find SHT_STMTAB.
+ for (const char *i = reinterpret_cast<const char *>(SectionHeaderTable),
+ *e = i + Header->e_shnum * Header->e_shentsize;
+ i != e; i += Header->e_shentsize) {
+ const Elf_Shdr *sh = reinterpret_cast<const Elf_Shdr*>(i);
+ if (sh->sh_type == ELF::SHT_SYMTAB) {
+ SymbolTableSections.push_back(sh);
+ }
+ }
+
+ // Get string table sections.
+ dot_shstrtab_sec = getSection(Header->e_shstrndx);
+ if (dot_shstrtab_sec) {
+ // Verify that the last byte in the string table in a null.
+ if (((const char*)base + dot_shstrtab_sec->sh_offset)
+ [dot_shstrtab_sec->sh_size - 1] != 0)
+ // FIXME: Proper error handling.
+ report_fatal_error("String table must end with a null terminator!");
+ }
+
+ // Merge this into the above loop.
+ for (const char *i = reinterpret_cast<const char *>(SectionHeaderTable),
+ *e = i + Header->e_shnum * Header->e_shentsize;
+ i != e; i += Header->e_shentsize) {
+ const Elf_Shdr *sh = reinterpret_cast<const Elf_Shdr*>(i);
+ if (sh->sh_type == ELF::SHT_STRTAB) {
+ StringRef SectionName(getString(dot_shstrtab_sec, sh->sh_name));
+ if (SectionName == ".strtab") {
+ if (dot_strtab_sec != 0)
+ // FIXME: Proper error handling.
+ report_fatal_error("Already found section named .strtab!");
+ dot_strtab_sec = sh;
+ const char *dot_strtab = (const char*)base + sh->sh_offset;
+ if (dot_strtab[sh->sh_size - 1] != 0)
+ // FIXME: Proper error handling.
+ report_fatal_error("String table must end with a null terminator!");
+ }
+ }
+ }
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+ObjectFile::symbol_iterator ELFObjectFile<target_endianness, is64Bits>
+ ::begin_symbols() const {
+ ELFDataRefImpl SymbolData;
+ memset(&SymbolData, 0, sizeof(SymbolData));
+ if (SymbolTableSections.size() == 0) {
+ SymbolData.SymbolIndex = std::numeric_limits<uint32_t>::max();
+ SymbolData.SymbolTableSectionIndex = std::numeric_limits<uint32_t>::max();
+ } else {
+ SymbolData.SymbolIndex = 1; // The 0th symbol in ELF is fake.
+ SymbolData.SymbolTableSectionIndex = 0;
+ }
+ return symbol_iterator(
+ SymbolRef(DataRefImpl(*reinterpret_cast<DataRefImpl*>(&SymbolData)), this));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+ObjectFile::symbol_iterator ELFObjectFile<target_endianness, is64Bits>
+ ::end_symbols() const {
+ ELFDataRefImpl SymbolData;
+ memset(&SymbolData, 0, sizeof(SymbolData));
+ SymbolData.SymbolIndex = std::numeric_limits<uint32_t>::max();
+ SymbolData.SymbolTableSectionIndex = std::numeric_limits<uint32_t>::max();
+ return symbol_iterator(
+ SymbolRef(DataRefImpl(*reinterpret_cast<DataRefImpl*>(&SymbolData)), this));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+ObjectFile::section_iterator ELFObjectFile<target_endianness, is64Bits>
+ ::begin_sections() const {
+ return section_iterator(
+ SectionRef(DataRefImpl(base + Header->e_shoff), this));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+ObjectFile::section_iterator ELFObjectFile<target_endianness, is64Bits>
+ ::end_sections() const {
+ return section_iterator(
+ SectionRef(DataRefImpl(base
+ + Header->e_shoff
+ + (Header->e_shentsize * Header->e_shnum)), this));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+uint8_t ELFObjectFile<target_endianness, is64Bits>::getBytesInAddress() const {
+ return 4;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+StringRef ELFObjectFile<target_endianness, is64Bits>
+ ::getFileFormatName() const {
+ switch(Header->e_ident[ELF::EI_CLASS]) {
+ case ELF::ELFCLASS32:
+ switch(Header->e_machine) {
+ case ELF::EM_386:
+ return "ELF32-i386";
+ case ELF::EM_X86_64:
+ return "ELF32-x86-64";
+ default:
+ return "ELF32-unknown";
+ }
+ case ELF::ELFCLASS64:
+ switch(Header->e_machine) {
+ case ELF::EM_386:
+ return "ELF64-i386";
+ case ELF::EM_X86_64:
+ return "ELF64-x86-64";
+ default:
+ return "ELF64-unknown";
+ }
+ default:
+ // FIXME: Proper error handling.
+ report_fatal_error("Invalid ELFCLASS!");
+ }
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+unsigned ELFObjectFile<target_endianness, is64Bits>::getArch() const {
+ switch(Header->e_machine) {
+ case ELF::EM_386:
+ return Triple::x86;
+ case ELF::EM_X86_64:
+ return Triple::x86_64;
+ default:
+ return Triple::UnknownArch;
+ }
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Sym *
+ELFObjectFile<target_endianness, is64Bits>::getSymbol(DataRefImpl Symb) const {
+ const ELFDataRefImpl SymbolData = *reinterpret_cast<ELFDataRefImpl *>(&Symb);
+ const Elf_Shdr *sec =
+ SymbolTableSections[SymbolData.SymbolTableSectionIndex];
+ return reinterpret_cast<const Elf_Sym *>(
+ base
+ + sec->sh_offset
+ + (SymbolData.SymbolIndex * sec->sh_entsize));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr *
+ELFObjectFile<target_endianness, is64Bits>::getSection(DataRefImpl Symb) const {
+ const ELFDataRefImpl SymbolData = *reinterpret_cast<ELFDataRefImpl *>(&Symb);
+ const Elf_Shdr *sec = getSection(SymbolData.SymbolTableSectionIndex);
+ if (sec->sh_type != ELF::SHT_SYMTAB)
+ // FIXME: Proper error handling.
+ report_fatal_error("Invalid symbol table section!");
+ return sec;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr *
+ELFObjectFile<target_endianness, is64Bits>::getSection(uint16_t index) const {
+ if (index == 0 || index >= ELF::SHN_LORESERVE)
+ return 0;
+ if (!SectionHeaderTable || index >= Header->e_shnum)
+ // FIXME: Proper error handling.
+ report_fatal_error("Invalid section index!");
+
+ return reinterpret_cast<const Elf_Shdr *>(
+ reinterpret_cast<const char *>(SectionHeaderTable)
+ + (index * Header->e_shentsize));
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+const char *ELFObjectFile<target_endianness, is64Bits>
+ ::getString(uint16_t section,
+ ELF::Elf32_Word offset) const {
+ return getString(getSection(section), offset);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+const char *ELFObjectFile<target_endianness, is64Bits>
+ ::getString(const Elf_Shdr *section,
+ ELF::Elf32_Word offset) const {
+ assert(section && section->sh_type == ELF::SHT_STRTAB && "Invalid section!");
+ if (offset >= section->sh_size)
+ // FIXME: Proper error handling.
+ report_fatal_error("Sybol name offset outside of string table!");
+ return (const char *)base + section->sh_offset + offset;
+}
+
+// EI_CLASS, EI_DATA.
+static std::pair<unsigned char, unsigned char>
+getElfArchType(MemoryBuffer *Object) {
+ if (Object->getBufferSize() < ELF::EI_NIDENT)
+ return std::make_pair((uint8_t)ELF::ELFCLASSNONE,(uint8_t)ELF::ELFDATANONE);
+ return std::make_pair( (uint8_t)Object->getBufferStart()[ELF::EI_CLASS]
+ , (uint8_t)Object->getBufferStart()[ELF::EI_DATA]);
+}
+
+namespace llvm {
+
+ ObjectFile *ObjectFile::createELFObjectFile(MemoryBuffer *Object) {
+ std::pair<unsigned char, unsigned char> Ident = getElfArchType(Object);
+ if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB)
+ return new ELFObjectFile<support::little, false>(Object);
+ else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB)
+ return new ELFObjectFile<support::big, false>(Object);
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB)
+ return new ELFObjectFile<support::little, true>(Object);
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB)
+ return new ELFObjectFile<support::big, true>(Object);
+ // FIXME: Proper error handling.
+ report_fatal_error("Not an ELF object file!");
+ }
+
+} // end namespace llvm
Modified: llvm/trunk/lib/Object/ObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/ObjectFile.cpp?rev=123896&r1=123895&r2=123896&view=diff
==============================================================================
--- llvm/trunk/lib/Object/ObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/ObjectFile.cpp Thu Jan 20 00:38:47 2011
@@ -45,7 +45,7 @@
case sys::ELF_Executable_FileType:
case sys::ELF_SharedObject_FileType:
case sys::ELF_Core_FileType:
- return 0;
+ return createELFObjectFile(Object);
case sys::Mach_O_Object_FileType:
case sys::Mach_O_Executable_FileType:
case sys::Mach_O_FixedVirtualMemorySharedLib_FileType:
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