-//===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
+//===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "dyld"
+#include "RuntimeDyldELF.h"
+#include "JITRegistrar.h"
+#include "ObjectImageCommon.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/IntervalMap.h"
-#include "RuntimeDyldImpl.h"
#include "llvm/Object/ObjectFile.h"
+#include "llvm/ExecutionEngine/ObjectImage.h"
+#include "llvm/ExecutionEngine/ObjectBuffer.h"
#include "llvm/Support/ELF.h"
#include "llvm/ADT/Triple.h"
+#include "llvm/Object/ELF.h"
using namespace llvm;
using namespace llvm::object;
-namespace llvm {
-
namespace {
-// FIXME: this function should probably not live here...
-//
-// Returns the name and address of an unrelocated symbol in an ELF section
-void getSymbolInfo(symbol_iterator Sym, uint64_t &Addr, StringRef &Name) {
- //FIXME: error checking here required to catch corrupt ELF objects...
- error_code Err = Sym->getName(Name);
+template<support::endianness target_endianness, bool is64Bits>
+class DyldELFObject : public ELFObjectFile<target_endianness, is64Bits> {
+ LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits)
- uint64_t AddrInSection;
- Err = Sym->getAddress(AddrInSection);
+ 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;
- SectionRef empty_section;
- section_iterator Section(empty_section);
- Err = Sym->getSection(Section);
+ typedef Elf_Ehdr_Impl<target_endianness, is64Bits> Elf_Ehdr;
- StringRef SectionContents;
- Section->getContents(SectionContents);
+ typedef typename ELFDataTypeTypedefHelper<
+ target_endianness, is64Bits>::value_type addr_type;
- Addr = reinterpret_cast<uint64_t>(SectionContents.data()) + AddrInSection;
-}
+public:
+ DyldELFObject(MemoryBuffer *Wrapper, error_code &ec);
-}
+ void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
+ void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr);
-bool RuntimeDyldELF::loadObject(MemoryBuffer *InputBuffer) {
- if (!isCompatibleFormat(InputBuffer))
+ // 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 ObjectImageCommon {
+ protected:
+ DyldELFObject<target_endianness, is64Bits> *DyldObj;
+ bool Registered;
- OwningPtr<ObjectFile> Obj(ObjectFile::createELFObjectFile(InputBuffer));
-
- Arch = Obj->getArch();
-
- // Map address in the Object file image to function names
- IntervalMap<uint64_t, StringRef>::Allocator A;
- IntervalMap<uint64_t, StringRef> FuncMap(A);
-
- // This is a bit of a hack. The ObjectFile we've just loaded reports
- // section addresses as 0 and doesn't provide access to the section
- // offset (from which we could calculate the address. Instead,
- // we're storing the address when it comes up in the ST_Debug case
- // below.
- //
- StringMap<uint64_t> DebugSymbolMap;
-
- symbol_iterator SymEnd = Obj->end_symbols();
- error_code Err;
- for (symbol_iterator Sym = Obj->begin_symbols();
- Sym != SymEnd; Sym.increment(Err)) {
- SymbolRef::Type Type;
- Sym->getType(Type);
- if (Type == SymbolRef::ST_Function) {
- StringRef Name;
- uint64_t Addr;
- getSymbolInfo(Sym, Addr, Name);
-
- uint64_t Size;
- Err = Sym->getSize(Size);
-
- uint8_t *Start;
- uint8_t *End;
- Start = reinterpret_cast<uint8_t*>(Addr);
- End = reinterpret_cast<uint8_t*>(Addr + Size - 1);
-
- extractFunction(Name, Start, End);
- FuncMap.insert(Addr, Addr + Size - 1, Name);
- } else if (Type == SymbolRef::ST_Debug) {
- // This case helps us find section addresses
- StringRef Name;
- uint64_t Addr;
- getSymbolInfo(Sym, Addr, Name);
- DebugSymbolMap[Name] = Addr;
+ public:
+ ELFObjectImage(ObjectBuffer *Input,
+ DyldELFObject<target_endianness, is64Bits> *Obj)
+ : ObjectImageCommon(Input, Obj),
+ DyldObj(Obj),
+ Registered(false) {}
+
+ virtual ~ELFObjectImage() {
+ if (Registered)
+ deregisterWithDebugger();
}
- }
- // Iterate through the relocations for this object
- section_iterator SecEnd = Obj->end_sections();
- for (section_iterator Sec = Obj->begin_sections();
- Sec != SecEnd; Sec.increment(Err)) {
- StringRef SecName;
- uint64_t SecAddr;
- Sec->getName(SecName);
- // Ignore sections that aren't in our map
- if (DebugSymbolMap.find(SecName) == DebugSymbolMap.end()) {
- continue;
+ // 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);
}
- SecAddr = DebugSymbolMap[SecName];
- relocation_iterator RelEnd = Sec->end_relocations();
- for (relocation_iterator Rel = Sec->begin_relocations();
- Rel != RelEnd; Rel.increment(Err)) {
- uint64_t RelOffset;
- uint64_t RelType;
- int64_t RelAddend;
- SymbolRef RelSym;
- StringRef SymName;
- uint64_t SymAddr;
- uint64_t SymOffset;
-
- Rel->getAddress(RelOffset);
- Rel->getType(RelType);
- Rel->getAdditionalInfo(RelAddend);
- Rel->getSymbol(RelSym);
- RelSym.getName(SymName);
- RelSym.getAddress(SymAddr);
- RelSym.getFileOffset(SymOffset);
-
- // If this relocation is inside a function, we want to store the
- // function name and a function-relative offset
- IntervalMap<uint64_t, StringRef>::iterator ContainingFunc
- = FuncMap.find(SecAddr + RelOffset);
- if (ContainingFunc.valid()) {
- // Re-base the relocation to make it relative to the target function
- RelOffset = (SecAddr + RelOffset) - ContainingFunc.start();
- Relocations[SymName].push_back(RelocationEntry(ContainingFunc.value(),
- RelOffset,
- RelType,
- RelAddend,
- true));
- } else {
- Relocations[SymName].push_back(RelocationEntry(SecName,
- RelOffset,
- RelType,
- RelAddend,
- false));
- }
+
+ virtual void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr)
+ {
+ DyldObj->updateSymbolAddress(Sym, Addr);
}
- }
- return false;
+
+ virtual void registerWithDebugger()
+ {
+ JITRegistrar::getGDBRegistrar().registerObject(*Buffer);
+ Registered = true;
+ }
+ virtual void deregisterWithDebugger()
+ {
+ JITRegistrar::getGDBRegistrar().deregisterObject(*Buffer);
+ }
+};
+
+// The MemoryBuffer passed into this constructor is just a wrapper around the
+// actual memory. Ultimately, the Binary parent class will take ownership of
+// this MemoryBuffer object but not the underlying memory.
+template<support::endianness target_endianness, bool is64Bits>
+DyldELFObject<target_endianness, is64Bits>::DyldELFObject(MemoryBuffer *Wrapper,
+ error_code &ec)
+ : ELFObjectFile<target_endianness, is64Bits>(Wrapper, ec) {
+ this->isDyldELFObject = true;
}
-void RuntimeDyldELF::resolveX86_64Relocation(StringRef Name,
- uint8_t *Addr,
- const RelocationEntry &RE) {
- uint8_t *TargetAddr;
- if (RE.IsFunctionRelative) {
- StringMap<sys::MemoryBlock>::iterator ContainingFunc
- = Functions.find(RE.Target);
- assert(ContainingFunc != Functions.end()
- && "Function for relocation not found");
- TargetAddr = reinterpret_cast<uint8_t*>(ContainingFunc->getValue().base()) +
- RE.Offset;
- } else {
- // FIXME: Get the address of the target section and add that to RE.Offset
- assert(0 && ("Non-function relocation not implemented yet!"));
+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(ObjectBuffer *Buffer) {
+ if (Buffer->getBufferSize() < ELF::EI_NIDENT)
+ llvm_unreachable("Unexpected ELF object size");
+ std::pair<unsigned char, unsigned char> Ident = std::make_pair(
+ (uint8_t)Buffer->getBufferStart()[ELF::EI_CLASS],
+ (uint8_t)Buffer->getBufferStart()[ELF::EI_DATA]);
+ error_code ec;
+
+ if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB) {
+ DyldELFObject<support::little, false> *Obj =
+ new DyldELFObject<support::little, false>(Buffer->getMemBuffer(), ec);
+ return new ELFObjectImage<support::little, false>(Buffer, Obj);
+ }
+ else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) {
+ DyldELFObject<support::big, false> *Obj =
+ new DyldELFObject<support::big, false>(Buffer->getMemBuffer(), ec);
+ return new ELFObjectImage<support::big, false>(Buffer, Obj);
+ }
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) {
+ DyldELFObject<support::big, true> *Obj =
+ new DyldELFObject<support::big, true>(Buffer->getMemBuffer(), ec);
+ return new ELFObjectImage<support::big, true>(Buffer, Obj);
}
+ else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) {
+ DyldELFObject<support::little, true> *Obj =
+ new DyldELFObject<support::little, true>(Buffer->getMemBuffer(), ec);
+ return new ELFObjectImage<support::little, true>(Buffer, Obj);
+ }
+ else
+ llvm_unreachable("Unexpected ELF format");
+}
- switch (RE.Type) {
+RuntimeDyldELF::~RuntimeDyldELF() {
+}
+
+void RuntimeDyldELF::resolveX86_64Relocation(uint8_t *LocalAddress,
+ uint64_t FinalAddress,
+ uint64_t Value,
+ uint32_t Type,
+ int64_t Addend) {
+ switch (Type) {
default:
- assert(0 && ("Relocation type not implemented yet!"));
+ llvm_unreachable("Relocation type not implemented yet!");
break;
case ELF::R_X86_64_64: {
- uint8_t **Target = reinterpret_cast<uint8_t**>(TargetAddr);
- *Target = Addr + RE.Addend;
+ uint64_t *Target = (uint64_t*)(LocalAddress);
+ *Target = Value + Addend;
break;
}
case ELF::R_X86_64_32:
case ELF::R_X86_64_32S: {
- uint64_t Value = reinterpret_cast<uint64_t>(Addr) + RE.Addend;
- // FIXME: Handle the possibility of this assertion failing
- assert((RE.Type == ELF::R_X86_64_32 && !(Value & 0xFFFFFFFF00000000)) ||
- (RE.Type == ELF::R_X86_64_32S &&
- (Value & 0xFFFFFFFF00000000) == 0xFFFFFFFF00000000));
+ 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*>(TargetAddr);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(LocalAddress);
*Target = TruncatedAddr;
break;
}
case ELF::R_X86_64_PC32: {
- uint32_t *Placeholder = reinterpret_cast<uint32_t*>(TargetAddr);
- uint64_t RealOffset = *Placeholder +
- reinterpret_cast<uint64_t>(Addr) +
- RE.Addend - reinterpret_cast<uint64_t>(TargetAddr);
- assert((RealOffset & 0xFFFFFFFF) == RealOffset);
- uint32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
+ 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(StringRef Name,
- uint8_t *Addr,
- const RelocationEntry &RE) {
- uint8_t *TargetAddr;
- if (RE.IsFunctionRelative) {
- StringMap<sys::MemoryBlock>::iterator ContainingFunc
- = Functions.find(RE.Target);
- assert(ContainingFunc != Functions.end()
- && "Function for relocation not found");
- TargetAddr = reinterpret_cast<uint8_t*>(
- ContainingFunc->getValue().base()) + RE.Offset;
- } else {
- // FIXME: Get the address of the target section and add that to RE.Offset
- assert(0 && ("Non-function relocation not implemented yet!"));
- }
-
- switch (RE.Type) {
+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: {
- uint8_t **Target = reinterpret_cast<uint8_t**>(TargetAddr);
- *Target = Addr + RE.Addend;
+ 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*>(TargetAddr);
- uint32_t RealOffset = *Placeholder + reinterpret_cast<uintptr_t>(Addr) +
- RE.Addend - reinterpret_cast<uintptr_t>(TargetAddr);
+ 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
- assert(0 && ("Relocation type not implemented yet!"));
+ // only ones currently used by the LLVM ELF object writer
+ llvm_unreachable("Relocation type not implemented yet!");
break;
}
}
-void RuntimeDyldELF::resolveArmRelocation(StringRef Name,
- uint8_t *Addr,
- const RelocationEntry &RE) {
+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!");
+
+ // Write a 32bit value to relocation address, taking into account the
+ // implicit addend encoded in the target.
+ 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 :
+ // We are not expecting any other addend in the relocation address.
+ // Using 0x000F0FFF because MOVW has its 16 bit immediate split into 2
+ // non-contiguous fields.
+ assert((*TargetPtr & 0x000F0FFF) == 0);
+ 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 :
+ // We are not expecting any other addend in the relocation address.
+ // Use 0x000F0FFF for the same reason as R_ARM_MOVW_ABS_NC.
+ assert((*TargetPtr & 0x000F0FFF) == 0);
+ 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(StringRef Name,
- uint8_t *Addr,
- const RelocationEntry &RE) {
+void RuntimeDyldELF::resolveMIPSRelocation(uint8_t *LocalAddress,
+ uint32_t FinalAddress,
+ uint32_t Value,
+ uint32_t Type,
+ int32_t Addend) {
+ uint32_t* TargetPtr = (uint32_t*)LocalAddress;
+ Value += Addend;
+
+ DEBUG(dbgs() << "resolveMipselocation, 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!");
+ break;
+ case ELF::R_MIPS_32:
+ *TargetPtr = Value + (*TargetPtr);
+ break;
+ case ELF::R_MIPS_26:
+ *TargetPtr = ((*TargetPtr) & 0xfc000000) | (( Value & 0x0fffffff) >> 2);
+ break;
+ case ELF::R_MIPS_HI16:
+ // Get the higher 16-bits. Also add 1 if bit 15 is 1.
+ Value += ((*TargetPtr) & 0x0000ffff) << 16;
+ *TargetPtr = ((*TargetPtr) & 0xffff0000) |
+ (((Value + 0x8000) >> 16) & 0xffff);
+ break;
+ case ELF::R_MIPS_LO16:
+ Value += ((*TargetPtr) & 0x0000ffff);
+ *TargetPtr = ((*TargetPtr) & 0xffff0000) | (Value & 0xffff);
+ 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(Name, Addr, RE);
+ resolveX86_64Relocation(LocalAddress, FinalAddress, Value, Type, Addend);
break;
case Triple::x86:
- resolveX86Relocation(Name, Addr, RE);
+ resolveX86Relocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ (uint32_t)(Value & 0xffffffffL), Type,
+ (uint32_t)(Addend & 0xffffffffL));
break;
- case Triple::arm:
- resolveArmRelocation(Name, Addr, RE);
+ 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:
- assert(0 && "Unsupported CPU type!");
+ case Triple::mips: // Fall through.
+ case Triple::mipsel:
+ resolveMIPSRelocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ (uint32_t)(Value & 0xffffffffL), Type,
+ (uint32_t)(Addend & 0xffffffffL));
break;
+ default: llvm_unreachable("Unsupported CPU type!");
}
}
-void RuntimeDyldELF::reassignSymbolAddress(StringRef Name, uint8_t *Addr) {
- SymbolTable[Name] = Addr;
+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 if (Arch == Triple::mipsel && RelType == ELF::R_MIPS_26) {
+ // This is an Mips branch relocation, need to use a stub function.
+ DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
+ SectionEntry &Section = Sections[Rel.SectionID];
+ uint8_t *Target = Section.Address + Rel.Offset;
+ uint32_t *TargetAddress = (uint32_t *)Target;
+
+ // Extract the addend from the instruction.
+ uint32_t Addend = ((*TargetAddress) & 0x03ffffff) << 2;
+
+ Value.Addend += Addend;
+
+ // 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);
+
+ // Creating Hi and Lo relocations for the filled stub instructions.
+ RelocationEntry REHi(Rel.SectionID,
+ StubTargetAddr - Section.Address,
+ ELF::R_MIPS_HI16, Value.Addend);
+ RelocationEntry RELo(Rel.SectionID,
+ StubTargetAddr - Section.Address + 4,
+ ELF::R_MIPS_LO16, Value.Addend);
- RelocationList &Relocs = Relocations[Name];
- for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
- RelocationEntry &RE = Relocs[i];
- resolveRelocation(Name, Addr, RE);
+ if (Value.SymbolName) {
+ addRelocationForSymbol(REHi, Value.SymbolName);
+ addRelocationForSymbol(RELo, Value.SymbolName);
+ } else {
+ addRelocationForSection(REHi, Value.SectionID);
+ addRelocationForSection(RELo, 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;
+bool RuntimeDyldELF::isCompatibleFormat(const ObjectBuffer *Buffer) const {
+ if (Buffer->getBufferSize() < strlen(ELF::ElfMagic))
+ return false;
+ return (memcmp(Buffer->getBufferStart(), ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0;
}
} // namespace llvm
projects / oota-llvm.git / blobdiff