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diff --git a/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
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+++ b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
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+//===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Implementation of ELF support for the MC-JIT runtime dynamic linker.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "dyld"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/IntervalMap.h"
+#include "RuntimeDyldELF.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Object/ELF.h"
+#include "JITRegistrar.h"
+using namespace llvm;
+using namespace llvm::object;
+
+namespace {
+
+template<support::endianness target_endianness, bool is64Bits>
+class DyldELFObject : public ELFObjectFile<target_endianness, is64Bits> {
+ 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;
+ typedef Elf_Rel_Impl<target_endianness, is64Bits, false> Elf_Rel;
+ typedef Elf_Rel_Impl<target_endianness, is64Bits, true> Elf_Rela;
+
+ typedef typename ELFObjectFile<target_endianness, is64Bits>::
+ Elf_Ehdr Elf_Ehdr;
+
+ typedef typename ELFDataTypeTypedefHelper<
+ target_endianness, is64Bits>::value_type addr_type;
+
+protected:
+ // This duplicates the 'Data' member in the 'Binary' base class
+ // but it is necessary to workaround a bug in gcc 4.2
+ MemoryBuffer *InputData;
+
+public:
+ DyldELFObject(MemoryBuffer *Object, error_code &ec);
+
+ void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
+ void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr);
+
+ const MemoryBuffer& getBuffer() const { return *InputData; }
+
+ // Methods for type inquiry through isa, cast and dyn_cast
+ static inline bool classof(const Binary *v) {
+ return (isa<ELFObjectFile<target_endianness, is64Bits> >(v)
+ && classof(cast<ELFObjectFile<target_endianness, is64Bits> >(v)));
+ }
+ static inline bool classof(
+ const ELFObjectFile<target_endianness, is64Bits> *v) {
+ return v->isDyldType();
+ }
+ static inline bool classof(const DyldELFObject *v) {
+ return true;
+ }
+};
+
+template<support::endianness target_endianness, bool is64Bits>
+class ELFObjectImage : public ObjectImage {
+ protected:
+ DyldELFObject<target_endianness, is64Bits> *DyldObj;
+ bool Registered;
+
+ public:
+ ELFObjectImage(DyldELFObject<target_endianness, is64Bits> *Obj)
+ : ObjectImage(Obj),
+ DyldObj(Obj),
+ Registered(false) {}
+
+ virtual ~ELFObjectImage() {
+ if (Registered)
+ deregisterWithDebugger();
+ }
+
+ // Subclasses can override these methods to update the image with loaded
+ // addresses for sections and common symbols
+ virtual void updateSectionAddress(const SectionRef &Sec, uint64_t Addr)
+ {
+ DyldObj->updateSectionAddress(Sec, Addr);
+ }
+
+ virtual void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr)
+ {
+ DyldObj->updateSymbolAddress(Sym, Addr);
+ }
+
+ virtual void registerWithDebugger()
+ {
+ JITRegistrar::getGDBRegistrar().registerObject(DyldObj->getBuffer());
+ Registered = true;
+ }
+ virtual void deregisterWithDebugger()
+ {
+ JITRegistrar::getGDBRegistrar().deregisterObject(DyldObj->getBuffer());
+ }
+};
+
+template<support::endianness target_endianness, bool is64Bits>
+DyldELFObject<target_endianness, is64Bits>::DyldELFObject(MemoryBuffer *Object,
+ error_code &ec)
+ : ELFObjectFile<target_endianness, is64Bits>(Object, ec),
+ InputData(Object) {
+ this->isDyldELFObject = true;
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+void DyldELFObject<target_endianness, is64Bits>::updateSectionAddress(
+ const SectionRef &Sec,
+ uint64_t Addr) {
+ DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
+ Elf_Shdr *shdr = const_cast<Elf_Shdr*>(
+ reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
+
+ // This assumes the address passed in matches the target address bitness
+ // The template-based type cast handles everything else.
+ shdr->sh_addr = static_cast<addr_type>(Addr);
+}
+
+template<support::endianness target_endianness, bool is64Bits>
+void DyldELFObject<target_endianness, is64Bits>::updateSymbolAddress(
+ const SymbolRef &SymRef,
+ uint64_t Addr) {
+
+ Elf_Sym *sym = const_cast<Elf_Sym*>(
+ ELFObjectFile<target_endianness, is64Bits>::
+ getSymbol(SymRef.getRawDataRefImpl()));
+
+ // This assumes the address passed in matches the target address bitness
+ // The template-based type cast handles everything else.
+ sym->st_value = static_cast<addr_type>(Addr);
+}
+
+} // namespace
+
+
+namespace llvm {
+
+ObjectImage *RuntimeDyldELF::createObjectImage(
+ const MemoryBuffer *ConstInputBuffer) {
+ MemoryBuffer *InputBuffer = const_cast<MemoryBuffer*>(ConstInputBuffer);
+ std::pair<unsigned char, unsigned char> Ident = getElfArchType(InputBuffer);
+ error_code ec;
+
+ if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB) {
+ DyldELFObject<support::little, false> *Obj =
+ new DyldELFObject<support::little, false>(InputBuffer, ec);
+ return new ELFObjectImage<support::little, false>(Obj);
+ }
+ else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) {
+ DyldELFObject<support::big, false> *Obj =
+ new DyldELFObject<support::big, false>(InputBuffer, ec);
+ return new ELFObjectImage<support::big, false>(Obj);
+ }
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) {
+ DyldELFObject<support::big, true> *Obj =
+ new DyldELFObject<support::big, true>(InputBuffer, ec);
+ return new ELFObjectImage<support::big, true>(Obj);
+ }
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) {
+ DyldELFObject<support::little, true> *Obj =
+ new DyldELFObject<support::little, true>(InputBuffer, ec);
+ return new ELFObjectImage<support::little, true>(Obj);
+ }
+ else
+ llvm_unreachable("Unexpected ELF format");
+}
+
+void RuntimeDyldELF::handleObjectLoaded(ObjectImage *Obj)
+{
+ Obj->registerWithDebugger();
+ // Save the loaded object. It will deregister itself when deleted
+ LoadedObject = Obj;
+}
+
+RuntimeDyldELF::~RuntimeDyldELF() {
+ if (LoadedObject)
+ delete LoadedObject;
+}
+
+void RuntimeDyldELF::resolveX86_64Relocation(uint8_t *LocalAddress,
+ uint64_t FinalAddress,
+ uint64_t Value,
+ uint32_t Type,
+ int64_t Addend) {
+ switch (Type) {
+ default:
+ llvm_unreachable("Relocation type not implemented yet!");
+ break;
+ case ELF::R_X86_64_64: {
+ uint64_t *Target = (uint64_t*)(LocalAddress);
+ *Target = Value + Addend;
+ break;
+ }
+ case ELF::R_X86_64_32:
+ case ELF::R_X86_64_32S: {
+ Value += Addend;
+ assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
+ (Type == ELF::R_X86_64_32S &&
+ ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
+ uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(LocalAddress);
+ *Target = TruncatedAddr;
+ break;
+ }
+ case ELF::R_X86_64_PC32: {
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(LocalAddress);
+ int64_t RealOffset = *Placeholder + Value + Addend - FinalAddress;
+ assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
+ int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
+ *Placeholder = TruncOffset;
+ break;
+ }
+ }
+}
+
+void RuntimeDyldELF::resolveX86Relocation(uint8_t *LocalAddress,
+ uint32_t FinalAddress,
+ uint32_t Value,
+ uint32_t Type,
+ int32_t Addend) {
+ switch (Type) {
+ case ELF::R_386_32: {
+ uint32_t *Target = (uint32_t*)(LocalAddress);
+ uint32_t Placeholder = *Target;
+ *Target = Placeholder + Value + Addend;
+ break;
+ }
+ case ELF::R_386_PC32: {
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(LocalAddress);
+ uint32_t RealOffset = *Placeholder + Value + Addend - FinalAddress;
+ *Placeholder = RealOffset;
+ break;
+ }
+ default:
+ // There are other relocation types, but it appears these are the
+ // only ones currently used by the LLVM ELF object writer
+ llvm_unreachable("Relocation type not implemented yet!");
+ break;
+ }
+}
+
+void RuntimeDyldELF::resolveARMRelocation(uint8_t *LocalAddress,
+ uint32_t FinalAddress,
+ uint32_t Value,
+ uint32_t Type,
+ int32_t Addend) {
+ // TODO: Add Thumb relocations.
+ uint32_t* TargetPtr = (uint32_t*)LocalAddress;
+ Value += Addend;
+
+ DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: " << LocalAddress
+ << " FinalAddress: " << format("%p",FinalAddress)
+ << " Value: " << format("%x",Value)
+ << " Type: " << format("%x",Type)
+ << " Addend: " << format("%x",Addend)
+ << "\n");
+
+ switch(Type) {
+ default:
+ llvm_unreachable("Not implemented relocation type!");
+
+ // Just write 32bit value to relocation address
+ case ELF::R_ARM_ABS32 :
+ *TargetPtr = Value;
+ break;
+
+ // Write first 16 bit of 32 bit value to the mov instruction.
+ // Last 4 bit should be shifted.
+ case ELF::R_ARM_MOVW_ABS_NC :
+ Value = Value & 0xFFFF;
+ *TargetPtr |= Value & 0xFFF;
+ *TargetPtr |= ((Value >> 12) & 0xF) << 16;
+ break;
+
+ // Write last 16 bit of 32 bit value to the mov instruction.
+ // Last 4 bit should be shifted.
+ case ELF::R_ARM_MOVT_ABS :
+ Value = (Value >> 16) & 0xFFFF;
+ *TargetPtr |= Value & 0xFFF;
+ *TargetPtr |= ((Value >> 12) & 0xF) << 16;
+ break;
+
+ // Write 24 bit relative value to the branch instruction.
+ case ELF::R_ARM_PC24 : // Fall through.
+ case ELF::R_ARM_CALL : // Fall through.
+ case ELF::R_ARM_JUMP24 :
+ int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
+ RelValue = (RelValue & 0x03FFFFFC) >> 2;
+ *TargetPtr &= 0xFF000000;
+ *TargetPtr |= RelValue;
+ break;
+ }
+}
+
+void RuntimeDyldELF::resolveRelocation(uint8_t *LocalAddress,
+ uint64_t FinalAddress,
+ uint64_t Value,
+ uint32_t Type,
+ int64_t Addend) {
+ switch (Arch) {
+ case Triple::x86_64:
+ resolveX86_64Relocation(LocalAddress, FinalAddress, Value, Type, Addend);
+ break;
+ case Triple::x86:
+ resolveX86Relocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ (uint32_t)(Value & 0xffffffffL), Type,
+ (uint32_t)(Addend & 0xffffffffL));
+ break;
+ case Triple::arm: // Fall through.
+ case Triple::thumb:
+ resolveARMRelocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ (uint32_t)(Value & 0xffffffffL), Type,
+ (uint32_t)(Addend & 0xffffffffL));
+ break;
+ default: llvm_unreachable("Unsupported CPU type!");
+ }
+}
+
+void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel,
+ ObjectImage &Obj,
+ ObjSectionToIDMap &ObjSectionToID,
+ const SymbolTableMap &Symbols,
+ StubMap &Stubs) {
+
+ uint32_t RelType = (uint32_t)(Rel.Type & 0xffffffffL);
+ intptr_t Addend = (intptr_t)Rel.AdditionalInfo;
+ const SymbolRef &Symbol = Rel.Symbol;
+
+ // Obtain the symbol name which is referenced in the relocation
+ StringRef TargetName;
+ Symbol.getName(TargetName);
+ DEBUG(dbgs() << "\t\tRelType: " << RelType
+ << " Addend: " << Addend
+ << " TargetName: " << TargetName
+ << "\n");
+ RelocationValueRef Value;
+ // First search for the symbol in the local symbol table
+ SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
+ if (lsi != Symbols.end()) {
+ Value.SectionID = lsi->second.first;
+ Value.Addend = lsi->second.second;
+ } else {
+ // Search for the symbol in the global symbol table
+ SymbolTableMap::const_iterator gsi =
+ GlobalSymbolTable.find(TargetName.data());
+ if (gsi != GlobalSymbolTable.end()) {
+ Value.SectionID = gsi->second.first;
+ Value.Addend = gsi->second.second;
+ } else {
+ SymbolRef::Type SymType;
+ Symbol.getType(SymType);
+ switch (SymType) {
+ case SymbolRef::ST_Debug: {
+ // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
+ // and can be changed by another developers. Maybe best way is add
+ // a new symbol type ST_Section to SymbolRef and use it.
+ section_iterator si(Obj.end_sections());
+ Symbol.getSection(si);
+ if (si == Obj.end_sections())
+ llvm_unreachable("Symbol section not found, bad object file format!");
+ DEBUG(dbgs() << "\t\tThis is section symbol\n");
+ Value.SectionID = findOrEmitSection(Obj, (*si), true, ObjSectionToID);
+ Value.Addend = Addend;
+ break;
+ }
+ case SymbolRef::ST_Unknown: {
+ Value.SymbolName = TargetName.data();
+ Value.Addend = Addend;
+ break;
+ }
+ default:
+ llvm_unreachable("Unresolved symbol type!");
+ break;
+ }
+ }
+ }
+ DEBUG(dbgs() << "\t\tRel.SectionID: " << Rel.SectionID
+ << " Rel.Offset: " << Rel.Offset
+ << "\n");
+ if (Arch == Triple::arm &&
+ (RelType == ELF::R_ARM_PC24 ||
+ RelType == ELF::R_ARM_CALL ||
+ RelType == ELF::R_ARM_JUMP24)) {
+ // This is an ARM branch relocation, need to use a stub function.
+ DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
+ SectionEntry &Section = Sections[Rel.SectionID];
+ uint8_t *Target = Section.Address + Rel.Offset;
+
+ // Look up for existing stub.
+ StubMap::const_iterator i = Stubs.find(Value);
+ if (i != Stubs.end()) {
+ resolveRelocation(Target, (uint64_t)Target, (uint64_t)Section.Address +
+ i->second, RelType, 0);
+ DEBUG(dbgs() << " Stub function found\n");
+ } else {
+ // Create a new stub function.
+ DEBUG(dbgs() << " Create a new stub function\n");
+ Stubs[Value] = Section.StubOffset;
+ uint8_t *StubTargetAddr = createStubFunction(Section.Address +
+ Section.StubOffset);
+ RelocationEntry RE(Rel.SectionID, StubTargetAddr - Section.Address,
+ ELF::R_ARM_ABS32, Value.Addend);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+
+ resolveRelocation(Target, (uint64_t)Target, (uint64_t)Section.Address +
+ Section.StubOffset, RelType, 0);
+ Section.StubOffset += getMaxStubSize();
+ }
+ } else {
+ RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+ }
+}
+
+bool RuntimeDyldELF::isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
+ StringRef Magic = InputBuffer->getBuffer().slice(0, ELF::EI_NIDENT);
+ return (memcmp(Magic.data(), ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0;
+}
+} // namespace llvm
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