X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FExecutionEngine%2FRuntimeDyld%2FRuntimeDyldELF.cpp;h=95421b35db5cf4c319340384a5a4bea35a0d2101;hp=1ebcaf7ba822e536008960e602826cc8cb884024;hb=25103832b272eaa009fd56d3fc9eb98ebb7c2f1a;hpb=a307a1cf859f4a523951ac887d094039547adeb5 diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp index 1ebcaf7ba82..95421b35db5 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp @@ -11,318 +11,463 @@ // //===----------------------------------------------------------------------===// -#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 "RuntimeDyldCheckerImpl.h" #include "llvm/ADT/IntervalMap.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Triple.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/Object/ELFObjectFile.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" +#include "llvm/Support/Endian.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/TargetRegistry.h" + using namespace llvm; using namespace llvm::object; -namespace { +#define DEBUG_TYPE "dyld" -static inline -error_code check(error_code Err) { +static inline std::error_code check(std::error_code Err) { if (Err) { report_fatal_error(Err.message()); } return Err; } -template -class DyldELFObject : public ELFObjectFile { - LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits) +namespace { + +template class DyldELFObject : public ELFObjectFile { + LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) - typedef Elf_Shdr_Impl Elf_Shdr; - typedef Elf_Sym_Impl Elf_Sym; - typedef Elf_Rel_Impl Elf_Rel; - typedef Elf_Rel_Impl Elf_Rela; + typedef Elf_Shdr_Impl Elf_Shdr; + typedef Elf_Sym_Impl Elf_Sym; + typedef Elf_Rel_Impl Elf_Rel; + typedef Elf_Rel_Impl Elf_Rela; - typedef Elf_Ehdr_Impl Elf_Ehdr; + typedef Elf_Ehdr_Impl Elf_Ehdr; - typedef typename ELFDataTypeTypedefHelper< - target_endianness, is64Bits>::value_type addr_type; + typedef typename ELFDataTypeTypedefHelper::value_type addr_type; public: - DyldELFObject(MemoryBuffer *Wrapper, error_code &ec); + DyldELFObject(MemoryBufferRef Wrapper, std::error_code &ec); void updateSectionAddress(const SectionRef &Sec, uint64_t Addr); - void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr); + + void updateSymbolAddress(const SymbolRef &SymRef, uint64_t Addr); // Methods for type inquiry through isa, cast and dyn_cast static inline bool classof(const Binary *v) { - return (isa >(v) - && classof(cast >(v))); + return (isa>(v) && + classof(cast>(v))); } - static inline bool classof( - const ELFObjectFile *v) { + static inline bool classof(const ELFObjectFile *v) { return v->isDyldType(); } -}; -template -class ELFObjectImage : public ObjectImageCommon { - protected: - DyldELFObject *DyldObj; - bool Registered; - - public: - ELFObjectImage(ObjectBuffer *Input, - DyldELFObject *Obj) - : ObjectImageCommon(Input, 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(*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 -DyldELFObject::DyldELFObject(MemoryBuffer *Wrapper, - error_code &ec) - : ELFObjectFile(Wrapper, ec) { +template +DyldELFObject::DyldELFObject(MemoryBufferRef Wrapper, std::error_code &EC) + : ELFObjectFile(Wrapper, EC) { this->isDyldELFObject = true; } -template -void DyldELFObject::updateSectionAddress( - const SectionRef &Sec, - uint64_t Addr) { +template +void DyldELFObject::updateSectionAddress(const SectionRef &Sec, + uint64_t Addr) { DataRefImpl ShdrRef = Sec.getRawDataRefImpl(); - Elf_Shdr *shdr = const_cast( - reinterpret_cast(ShdrRef.p)); + Elf_Shdr *shdr = + const_cast(reinterpret_cast(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); } -template -void DyldELFObject::updateSymbolAddress( - const SymbolRef &SymRef, - uint64_t Addr) { +template +void DyldELFObject::updateSymbolAddress(const SymbolRef &SymRef, + uint64_t Addr) { - Elf_Sym *sym = const_cast( - ELFObjectFile:: - getSymbol(SymRef.getRawDataRefImpl())); + Elf_Sym *sym = const_cast( + ELFObjectFile::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); } -} // namespace +class LoadedELFObjectInfo + : public RuntimeDyld::LoadedObjectInfoHelper { +public: + LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, unsigned BeginIdx, + unsigned EndIdx) + : LoadedObjectInfoHelper(RTDyld, BeginIdx, EndIdx) {} + OwningBinary + getObjectForDebug(const ObjectFile &Obj) const override; +}; -namespace llvm { +template +std::unique_ptr> +createRTDyldELFObject(MemoryBufferRef Buffer, + const LoadedELFObjectInfo &L, + std::error_code &ec) { + typedef typename ELFFile::Elf_Shdr Elf_Shdr; + typedef typename ELFDataTypeTypedefHelper::value_type addr_type; + + std::unique_ptr> Obj = + llvm::make_unique>(Buffer, ec); -ObjectImage *RuntimeDyldELF::createObjectImage(ObjectBuffer *Buffer) { - if (Buffer->getBufferSize() < ELF::EI_NIDENT) - llvm_unreachable("Unexpected ELF object size"); - std::pair 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 *Obj = - new DyldELFObject(Buffer->getMemBuffer(), ec); - return new ELFObjectImage(Buffer, Obj); - } - else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) { - DyldELFObject *Obj = - new DyldELFObject(Buffer->getMemBuffer(), ec); - return new ELFObjectImage(Buffer, Obj); - } - else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) { - DyldELFObject *Obj = - new DyldELFObject(Buffer->getMemBuffer(), ec); - return new ELFObjectImage(Buffer, Obj); - } - else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) { - DyldELFObject *Obj = - new DyldELFObject(Buffer->getMemBuffer(), ec); - return new ELFObjectImage(Buffer, Obj); + // Iterate over all sections in the object. + for (const auto &Sec : Obj->sections()) { + StringRef SectionName; + Sec.getName(SectionName); + if (SectionName != "") { + DataRefImpl ShdrRef = Sec.getRawDataRefImpl(); + Elf_Shdr *shdr = const_cast( + reinterpret_cast(ShdrRef.p)); + + if (uint64_t SecLoadAddr = L.getSectionLoadAddress(SectionName)) { + // This assumes that the address passed in matches the target address + // bitness. The template-based type cast handles everything else. + shdr->sh_addr = static_cast(SecLoadAddr); + } + } } - else + + return Obj; +} + +OwningBinary createELFDebugObject(const ObjectFile &Obj, + const LoadedELFObjectInfo &L) { + assert(Obj.isELF() && "Not an ELF object file."); + + std::unique_ptr Buffer = + MemoryBuffer::getMemBufferCopy(Obj.getData(), Obj.getFileName()); + + std::error_code ec; + + std::unique_ptr DebugObj; + if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian()) { + typedef ELFType ELF32LE; + DebugObj = createRTDyldELFObject(Buffer->getMemBufferRef(), L, ec); + } else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian()) { + typedef ELFType ELF32BE; + DebugObj = createRTDyldELFObject(Buffer->getMemBufferRef(), L, ec); + } else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian()) { + typedef ELFType ELF64BE; + DebugObj = createRTDyldELFObject(Buffer->getMemBufferRef(), L, ec); + } else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian()) { + typedef ELFType ELF64LE; + DebugObj = createRTDyldELFObject(Buffer->getMemBufferRef(), L, ec); + } else llvm_unreachable("Unexpected ELF format"); + + assert(!ec && "Could not construct copy ELF object file"); + + return OwningBinary(std::move(DebugObj), std::move(Buffer)); } -RuntimeDyldELF::~RuntimeDyldELF() { +OwningBinary +LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const { + return createELFDebugObject(Obj, *this); +} + +} // namespace + +namespace llvm { + +RuntimeDyldELF::RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr, + RuntimeDyld::SymbolResolver &Resolver) + : RuntimeDyldImpl(MemMgr, Resolver), GOTSectionID(0), CurrentGOTIndex(0) {} +RuntimeDyldELF::~RuntimeDyldELF() {} + +void RuntimeDyldELF::registerEHFrames() { + for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) { + SID EHFrameSID = UnregisteredEHFrameSections[i]; + uint8_t *EHFrameAddr = Sections[EHFrameSID].Address; + uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress; + size_t EHFrameSize = Sections[EHFrameSID].Size; + MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize); + RegisteredEHFrameSections.push_back(EHFrameSID); + } + UnregisteredEHFrameSections.clear(); +} + +void RuntimeDyldELF::deregisterEHFrames() { + for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) { + SID EHFrameSID = RegisteredEHFrameSections[i]; + uint8_t *EHFrameAddr = Sections[EHFrameSID].Address; + uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress; + size_t EHFrameSize = Sections[EHFrameSID].Size; + MemMgr.deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize); + } + RegisteredEHFrameSections.clear(); +} + +std::unique_ptr +RuntimeDyldELF::loadObject(const object::ObjectFile &O) { + unsigned SectionStartIdx, SectionEndIdx; + std::tie(SectionStartIdx, SectionEndIdx) = loadObjectImpl(O); + return llvm::make_unique(*this, SectionStartIdx, + SectionEndIdx); } void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section, - uint64_t Offset, - uint64_t Value, - uint32_t Type, - int64_t Addend) { + uint64_t Offset, uint64_t Value, + uint32_t Type, int64_t Addend, + uint64_t SymOffset) { switch (Type) { default: llvm_unreachable("Relocation type not implemented yet!"); - break; + break; case ELF::R_X86_64_64: { - uint64_t *Target = reinterpret_cast(Section.Address + Offset); - *Target = Value + Addend; - DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) - << " at " << format("%p\n",Target)); + support::ulittle64_t::ref(Section.Address + Offset) = Value + Addend; + DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at " + << format("%p\n", Section.Address + Offset)); 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))); + (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(Section.Address + Offset); - *Target = TruncatedAddr; - DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) - << " at " << format("%p\n",Target)); + support::ulittle32_t::ref(Section.Address + Offset) = TruncatedAddr; + DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) << " at " + << format("%p\n", Section.Address + Offset)); break; } case ELF::R_X86_64_PC32: { - // Get the placeholder value from the generated object since - // a previous relocation attempt may have overwritten the loaded version - uint32_t *Placeholder = reinterpret_cast(Section.ObjAddress - + Offset); - uint32_t *Target = reinterpret_cast(Section.Address + Offset); - uint64_t FinalAddress = Section.LoadAddress + Offset; - int64_t RealOffset = *Placeholder + Value + Addend - FinalAddress; - assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN); + uint64_t FinalAddress = Section.LoadAddress + Offset; + int64_t RealOffset = Value + Addend - FinalAddress; + assert(isInt<32>(RealOffset)); int32_t TruncOffset = (RealOffset & 0xFFFFFFFF); - *Target = TruncOffset; + support::ulittle32_t::ref(Section.Address + Offset) = TruncOffset; + break; + } + case ELF::R_X86_64_PC64: { + uint64_t FinalAddress = Section.LoadAddress + Offset; + int64_t RealOffset = Value + Addend - FinalAddress; + support::ulittle64_t::ref(Section.Address + Offset) = RealOffset; break; } } } void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section, - uint64_t Offset, - uint32_t Value, - uint32_t Type, - int32_t Addend) { + uint64_t Offset, uint32_t Value, + uint32_t Type, int32_t Addend) { switch (Type) { case ELF::R_386_32: { - // Get the placeholder value from the generated object since - // a previous relocation attempt may have overwritten the loaded version - uint32_t *Placeholder = reinterpret_cast(Section.ObjAddress - + Offset); - uint32_t *Target = reinterpret_cast(Section.Address + Offset); - *Target = *Placeholder + Value + Addend; + support::ulittle32_t::ref(Section.Address + Offset) = Value + Addend; break; } case ELF::R_386_PC32: { - // Get the placeholder value from the generated object since - // a previous relocation attempt may have overwritten the loaded version - uint32_t *Placeholder = reinterpret_cast(Section.ObjAddress - + Offset); - uint32_t *Target = reinterpret_cast(Section.Address + Offset); - uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF); - uint32_t RealOffset = *Placeholder + Value + Addend - FinalAddress; - *Target = RealOffset; + uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF); + uint32_t RealOffset = Value + Addend - FinalAddress; + support::ulittle32_t::ref(Section.Address + Offset) = 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; - } - 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::resolveAArch64Relocation(const SectionEntry &Section, + uint64_t Offset, uint64_t Value, + uint32_t Type, int64_t Addend) { + uint32_t *TargetPtr = reinterpret_cast(Section.Address + Offset); + uint64_t FinalAddress = Section.LoadAddress + Offset; + + DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x" + << format("%llx", Section.Address + Offset) + << " FinalAddress: 0x" << format("%llx", FinalAddress) + << " Value: 0x" << format("%llx", Value) << " Type: 0x" + << format("%x", Type) << " Addend: 0x" << format("%llx", Addend) + << "\n"); + + switch (Type) { + default: + llvm_unreachable("Relocation type not implemented yet!"); + break; + case ELF::R_AARCH64_ABS64: { + uint64_t *TargetPtr = + reinterpret_cast(Section.Address + Offset); + *TargetPtr = Value + Addend; + break; + } + case ELF::R_AARCH64_PREL32: { + uint64_t Result = Value + Addend - FinalAddress; + assert(static_cast(Result) >= INT32_MIN && + static_cast(Result) <= UINT32_MAX); + *TargetPtr = static_cast(Result & 0xffffffffU); + break; + } + case ELF::R_AARCH64_CALL26: // fallthrough + case ELF::R_AARCH64_JUMP26: { + // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the + // calculation. + uint64_t BranchImm = Value + Addend - FinalAddress; + + // "Check that -2^27 <= result < 2^27". + assert(isInt<28>(BranchImm)); + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xfc000000U; + // Immediate goes in bits 25:0 of B and BL. + *TargetPtr |= static_cast(BranchImm & 0xffffffcU) >> 2; + break; + } + case ELF::R_AARCH64_MOVW_UABS_G3: { + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffe0001fU; + // Immediate goes in bits 20:5 of MOVZ/MOVK instruction + *TargetPtr |= Result >> (48 - 5); + // Shift must be "lsl #48", in bits 22:21 + assert((*TargetPtr >> 21 & 0x3) == 3 && "invalid shift for relocation"); + break; + } + case ELF::R_AARCH64_MOVW_UABS_G2_NC: { + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffe0001fU; + // Immediate goes in bits 20:5 of MOVZ/MOVK instruction + *TargetPtr |= ((Result & 0xffff00000000ULL) >> (32 - 5)); + // Shift must be "lsl #32", in bits 22:21 + assert((*TargetPtr >> 21 & 0x3) == 2 && "invalid shift for relocation"); + break; + } + case ELF::R_AARCH64_MOVW_UABS_G1_NC: { + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffe0001fU; + // Immediate goes in bits 20:5 of MOVZ/MOVK instruction + *TargetPtr |= ((Result & 0xffff0000U) >> (16 - 5)); + // Shift must be "lsl #16", in bits 22:2 + assert((*TargetPtr >> 21 & 0x3) == 1 && "invalid shift for relocation"); + break; + } + case ELF::R_AARCH64_MOVW_UABS_G0_NC: { + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffe0001fU; + // Immediate goes in bits 20:5 of MOVZ/MOVK instruction + *TargetPtr |= ((Result & 0xffffU) << 5); + // Shift must be "lsl #0", in bits 22:21. + assert((*TargetPtr >> 21 & 0x3) == 0 && "invalid shift for relocation"); + break; + } + case ELF::R_AARCH64_ADR_PREL_PG_HI21: { + // Operation: Page(S+A) - Page(P) + uint64_t Result = + ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL); + + // Check that -2^32 <= X < 2^32 + assert(isInt<33>(Result) && "overflow check failed for relocation"); + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0x9f00001fU; + // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken + // from bits 32:12 of X. + *TargetPtr |= ((Result & 0x3000U) << (29 - 12)); + *TargetPtr |= ((Result & 0x1ffffc000ULL) >> (14 - 5)); + break; + } + case ELF::R_AARCH64_LDST32_ABS_LO12_NC: { + // Operation: S + A + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffc003ffU; + // Immediate goes in bits 21:10 of LD/ST instruction, taken + // from bits 11:2 of X + *TargetPtr |= ((Result & 0xffc) << (10 - 2)); + break; + } + case ELF::R_AARCH64_LDST64_ABS_LO12_NC: { + // Operation: S + A + uint64_t Result = Value + Addend; + + // AArch64 code is emitted with .rela relocations. The data already in any + // bits affected by the relocation on entry is garbage. + *TargetPtr &= 0xffc003ffU; + // Immediate goes in bits 21:10 of LD/ST instruction, taken + // from bits 11:3 of X + *TargetPtr |= ((Result & 0xff8) << (10 - 3)); + break; + } } } void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section, - uint64_t Offset, - uint32_t Value, - uint32_t Type, - int32_t Addend) { + uint64_t Offset, uint32_t Value, + uint32_t Type, int32_t Addend) { // TODO: Add Thumb relocations. - uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset); + uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset); uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF); Value += Addend; DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: " << Section.Address + Offset - << " FinalAddress: " << format("%p",FinalAddress) - << " Value: " << format("%x",Value) - << " Type: " << format("%x",Type) - << " Addend: " << format("%x",Addend) - << "\n"); + << " FinalAddress: " << format("%p", FinalAddress) << " Value: " + << format("%x", Value) << " Type: " << format("%x", Type) + << " Addend: " << format("%x", Addend) << "\n"); - switch(Type) { + 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; + case ELF::R_ARM_NONE: 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; + case ELF::R_ARM_PREL31: + case ELF::R_ARM_TARGET1: + case ELF::R_ARM_ABS32: + *TargetPtr = Value; 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; + // 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: + case ELF::R_ARM_MOVT_ABS: + if (Type == ELF::R_ARM_MOVW_ABS_NC) + Value = Value & 0xFFFF; + else if (Type == ELF::R_ARM_MOVT_ABS) + Value = (Value >> 16) & 0xFFFF; + *TargetPtr &= ~0x000F0FFF; *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 : + // 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(Value - FinalAddress - 8); RelValue = (RelValue & 0x03FFFFFC) >> 2; + assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE); *TargetPtr &= 0xFF000000; *TargetPtr |= RelValue; break; @@ -330,113 +475,111 @@ void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section, } void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section, - uint64_t Offset, - uint32_t Value, - uint32_t Type, - int32_t Addend) { - uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset); + uint64_t Offset, uint32_t Value, + uint32_t Type, int32_t Addend) { + uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset); Value += Addend; DEBUG(dbgs() << "resolveMipselocation, LocalAddress: " - << Section.Address + Offset - << " FinalAddress: " - << format("%p",Section.LoadAddress + Offset) - << " Value: " << format("%x",Value) - << " Type: " << format("%x",Type) - << " Addend: " << format("%x",Addend) - << "\n"); + << Section.Address + Offset << " FinalAddress: " + << format("%p", Section.LoadAddress + Offset) << " Value: " + << format("%x", Value) << " Type: " << format("%x", Type) + << " Addend: " << format("%x", Addend) << "\n"); - switch(Type) { + switch (Type) { default: llvm_unreachable("Not implemented relocation type!"); break; case ELF::R_MIPS_32: - *TargetPtr = Value + (*TargetPtr); + *TargetPtr = Value; break; case ELF::R_MIPS_26: - *TargetPtr = ((*TargetPtr) & 0xfc000000) | (( Value & 0x0fffffff) >> 2); + *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); + *TargetPtr = + ((*TargetPtr) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff); break; - case ELF::R_MIPS_LO16: - Value += ((*TargetPtr) & 0x0000ffff); + case ELF::R_MIPS_LO16: *TargetPtr = ((*TargetPtr) & 0xffff0000) | (Value & 0xffff); break; - } + } } -// Return the .TOC. section address to R_PPC64_TOC relocations. -uint64_t RuntimeDyldELF::findPPC64TOC() const { +// Return the .TOC. section and offset. +void RuntimeDyldELF::findPPC64TOCSection(const ObjectFile &Obj, + ObjSectionToIDMap &LocalSections, + RelocationValueRef &Rel) { + // Set a default SectionID in case we do not find a TOC section below. + // This may happen for references to TOC base base (sym@toc, .odp + // relocation) without a .toc directive. In this case just use the + // first section (which is usually the .odp) since the code won't + // reference the .toc base directly. + Rel.SymbolName = NULL; + Rel.SectionID = 0; + // The TOC consists of sections .got, .toc, .tocbss, .plt in that // order. The TOC starts where the first of these sections starts. - SectionList::const_iterator it = Sections.begin(); - SectionList::const_iterator ite = Sections.end(); - for (; it != ite; ++it) { - if (it->Name == ".got" || - it->Name == ".toc" || - it->Name == ".tocbss" || - it->Name == ".plt") + for (section_iterator si = Obj.section_begin(), se = Obj.section_end(); + si != se; ++si) { + + StringRef SectionName; + check(si->getName(SectionName)); + + if (SectionName == ".got" + || SectionName == ".toc" + || SectionName == ".tocbss" + || SectionName == ".plt") { + Rel.SectionID = findOrEmitSection(Obj, *si, false, LocalSections); break; + } } - if (it == ite) { - // This may happen for - // * references to TOC base base (sym@toc, .odp relocation) without - // a .toc directive. - // In this case just use the first section (which is usually - // the .odp) since the code won't reference the .toc base - // directly. - it = Sections.begin(); - } - assert (it != ite); + // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000 // thus permitting a full 64 Kbytes segment. - return it->LoadAddress + 0x8000; + Rel.Addend = 0x8000; } // Returns the sections and offset associated with the ODP entry referenced // by Symbol. -void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj, +void RuntimeDyldELF::findOPDEntrySection(const ObjectFile &Obj, ObjSectionToIDMap &LocalSections, RelocationValueRef &Rel) { // Get the ELF symbol value (st_value) to compare with Relocation offset in // .opd entries - - error_code err; - for (section_iterator si = Obj.begin_sections(), - se = Obj.end_sections(); si != se; si.increment(err)) { - StringRef SectionName; - check(si->getName(SectionName)); - if (SectionName != ".opd") + for (section_iterator si = Obj.section_begin(), se = Obj.section_end(); + si != se; ++si) { + section_iterator RelSecI = si->getRelocatedSection(); + if (RelSecI == Obj.section_end()) continue; - for (relocation_iterator i = si->begin_relocations(), - e = si->end_relocations(); i != e;) { - check(err); + StringRef RelSectionName; + check(RelSecI->getName(RelSectionName)); + if (RelSectionName != ".opd") + continue; + for (relocation_iterator i = si->relocation_begin(), + e = si->relocation_end(); + i != e;) { // The R_PPC64_ADDR64 relocation indicates the first field // of a .opd entry uint64_t TypeFunc; check(i->getType(TypeFunc)); if (TypeFunc != ELF::R_PPC64_ADDR64) { - i.increment(err); + ++i; continue; } - SymbolRef TargetSymbol; uint64_t TargetSymbolOffset; - int64_t TargetAdditionalInfo; - check(i->getSymbol(TargetSymbol)); + symbol_iterator TargetSymbol = i->getSymbol(); check(i->getOffset(TargetSymbolOffset)); - check(i->getAdditionalInfo(TargetAdditionalInfo)); + int64_t Addend; + check(getELFRelocationAddend(*i, Addend)); - i = i.increment(err); + ++i; if (i == e) break; - check(err); // Just check if following relocation is a R_PPC64_TOC uint64_t TypeTOC; @@ -447,76 +590,117 @@ void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj, // Finally compares the Symbol value and the target symbol offset // to check if this .opd entry refers to the symbol the relocation // points to. - if (Rel.Addend != (intptr_t)TargetSymbolOffset) + if (Rel.Addend != (int64_t)TargetSymbolOffset) continue; - section_iterator tsi(Obj.end_sections()); - check(TargetSymbol.getSection(tsi)); - Rel.SectionID = findOrEmitSection(Obj, (*tsi), true, LocalSections); - Rel.Addend = (intptr_t)TargetAdditionalInfo; + section_iterator tsi(Obj.section_end()); + check(TargetSymbol->getSection(tsi)); + bool IsCode = tsi->isText(); + Rel.SectionID = findOrEmitSection(Obj, (*tsi), IsCode, LocalSections); + Rel.Addend = (intptr_t)Addend; return; } } llvm_unreachable("Attempting to get address of ODP entry!"); } -// Relocation masks following the #lo(value), #hi(value), #higher(value), -// and #highest(value) macros defined in section 4.5.1. Relocation Types -// in PPC-elf64abi document. -// -static inline -uint16_t applyPPClo (uint64_t value) -{ - return value & 0xffff; -} +// Relocation masks following the #lo(value), #hi(value), #ha(value), +// #higher(value), #highera(value), #highest(value), and #highesta(value) +// macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi +// document. -static inline -uint16_t applyPPChi (uint64_t value) -{ +static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; } + +static inline uint16_t applyPPChi(uint64_t value) { return (value >> 16) & 0xffff; } -static inline -uint16_t applyPPChigher (uint64_t value) -{ +static inline uint16_t applyPPCha (uint64_t value) { + return ((value + 0x8000) >> 16) & 0xffff; +} + +static inline uint16_t applyPPChigher(uint64_t value) { return (value >> 32) & 0xffff; } -static inline -uint16_t applyPPChighest (uint64_t value) -{ +static inline uint16_t applyPPChighera (uint64_t value) { + return ((value + 0x8000) >> 32) & 0xffff; +} + +static inline uint16_t applyPPChighest(uint64_t value) { return (value >> 48) & 0xffff; } +static inline uint16_t applyPPChighesta (uint64_t value) { + return ((value + 0x8000) >> 48) & 0xffff; +} + void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section, - uint64_t Offset, - uint64_t Value, - uint32_t Type, - int64_t Addend) { - uint8_t* LocalAddress = Section.Address + Offset; + uint64_t Offset, uint64_t Value, + uint32_t Type, int64_t Addend) { + uint8_t *LocalAddress = Section.Address + Offset; switch (Type) { default: llvm_unreachable("Relocation type not implemented yet!"); - break; - case ELF::R_PPC64_ADDR16_LO : - writeInt16BE(LocalAddress, applyPPClo (Value + Addend)); break; - case ELF::R_PPC64_ADDR16_HI : - writeInt16BE(LocalAddress, applyPPChi (Value + Addend)); + case ELF::R_PPC64_ADDR16: + writeInt16BE(LocalAddress, applyPPClo(Value + Addend)); + break; + case ELF::R_PPC64_ADDR16_DS: + writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3); + break; + case ELF::R_PPC64_ADDR16_LO: + writeInt16BE(LocalAddress, applyPPClo(Value + Addend)); + break; + case ELF::R_PPC64_ADDR16_LO_DS: + writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3); + break; + case ELF::R_PPC64_ADDR16_HI: + writeInt16BE(LocalAddress, applyPPChi(Value + Addend)); + break; + case ELF::R_PPC64_ADDR16_HA: + writeInt16BE(LocalAddress, applyPPCha(Value + Addend)); + break; + case ELF::R_PPC64_ADDR16_HIGHER: + writeInt16BE(LocalAddress, applyPPChigher(Value + Addend)); break; - case ELF::R_PPC64_ADDR16_HIGHER : - writeInt16BE(LocalAddress, applyPPChigher (Value + Addend)); + case ELF::R_PPC64_ADDR16_HIGHERA: + writeInt16BE(LocalAddress, applyPPChighera(Value + Addend)); break; - case ELF::R_PPC64_ADDR16_HIGHEST : - writeInt16BE(LocalAddress, applyPPChighest (Value + Addend)); + case ELF::R_PPC64_ADDR16_HIGHEST: + writeInt16BE(LocalAddress, applyPPChighest(Value + Addend)); break; - case ELF::R_PPC64_ADDR14 : { + case ELF::R_PPC64_ADDR16_HIGHESTA: + writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend)); + break; + case ELF::R_PPC64_ADDR14: { assert(((Value + Addend) & 3) == 0); // Preserve the AA/LK bits in the branch instruction - uint8_t aalk = *(LocalAddress+3); + uint8_t aalk = *(LocalAddress + 3); writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc)); } break; - case ELF::R_PPC64_REL24 : { + case ELF::R_PPC64_REL16_LO: { + uint64_t FinalAddress = (Section.LoadAddress + Offset); + uint64_t Delta = Value - FinalAddress + Addend; + writeInt16BE(LocalAddress, applyPPClo(Delta)); + } break; + case ELF::R_PPC64_REL16_HI: { + uint64_t FinalAddress = (Section.LoadAddress + Offset); + uint64_t Delta = Value - FinalAddress + Addend; + writeInt16BE(LocalAddress, applyPPChi(Delta)); + } break; + case ELF::R_PPC64_REL16_HA: { + uint64_t FinalAddress = (Section.LoadAddress + Offset); + uint64_t Delta = Value - FinalAddress + Addend; + writeInt16BE(LocalAddress, applyPPCha(Delta)); + } break; + case ELF::R_PPC64_ADDR32: { + int32_t Result = static_cast(Value + Addend); + if (SignExtend32<32>(Result) != Result) + llvm_unreachable("Relocation R_PPC64_ADDR32 overflow"); + writeInt32BE(LocalAddress, Result); + } break; + case ELF::R_PPC64_REL24: { uint64_t FinalAddress = (Section.LoadAddress + Offset); int32_t delta = static_cast(Value - FinalAddress + Addend); if (SignExtend32<24>(delta) != delta) @@ -524,221 +708,382 @@ void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section, // Generates a 'bl
' instruction writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC)); } break; - case ELF::R_PPC64_ADDR64 : + case ELF::R_PPC64_REL32: { + uint64_t FinalAddress = (Section.LoadAddress + Offset); + int32_t delta = static_cast(Value - FinalAddress + Addend); + if (SignExtend32<32>(delta) != delta) + llvm_unreachable("Relocation R_PPC64_REL32 overflow"); + writeInt32BE(LocalAddress, delta); + } break; + case ELF::R_PPC64_REL64: { + uint64_t FinalAddress = (Section.LoadAddress + Offset); + uint64_t Delta = Value - FinalAddress + Addend; + writeInt64BE(LocalAddress, Delta); + } break; + case ELF::R_PPC64_ADDR64: writeInt64BE(LocalAddress, Value + Addend); break; - case ELF::R_PPC64_TOC : - writeInt64BE(LocalAddress, findPPC64TOC()); + } +} + +void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section, + uint64_t Offset, uint64_t Value, + uint32_t Type, int64_t Addend) { + uint8_t *LocalAddress = Section.Address + Offset; + switch (Type) { + default: + llvm_unreachable("Relocation type not implemented yet!"); + break; + case ELF::R_390_PC16DBL: + case ELF::R_390_PLT16DBL: { + int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset); + assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow"); + writeInt16BE(LocalAddress, Delta / 2); + break; + } + case ELF::R_390_PC32DBL: + case ELF::R_390_PLT32DBL: { + int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset); + assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow"); + writeInt32BE(LocalAddress, Delta / 2); + break; + } + case ELF::R_390_PC32: { + int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset); + assert(int32_t(Delta) == Delta && "R_390_PC32 overflow"); + writeInt32BE(LocalAddress, Delta); + break; + } + case ELF::R_390_64: + writeInt64BE(LocalAddress, Value + Addend); break; - case ELF::R_PPC64_TOC16 : { - uint64_t TOCStart = findPPC64TOC(); - Value = applyPPClo((Value + Addend) - TOCStart); - writeInt16BE(LocalAddress, applyPPClo(Value)); - } break; - case ELF::R_PPC64_TOC16_DS : { - uint64_t TOCStart = findPPC64TOC(); - Value = ((Value + Addend) - TOCStart); - writeInt16BE(LocalAddress, applyPPClo(Value)); - } break; } } +// The target location for the relocation is described by RE.SectionID and +// RE.Offset. RE.SectionID can be used to find the SectionEntry. Each +// SectionEntry has three members describing its location. +// SectionEntry::Address is the address at which the section has been loaded +// into memory in the current (host) process. SectionEntry::LoadAddress is the +// address that the section will have in the target process. +// SectionEntry::ObjAddress is the address of the bits for this section in the +// original emitted object image (also in the current address space). +// +// Relocations will be applied as if the section were loaded at +// SectionEntry::LoadAddress, but they will be applied at an address based +// on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to +// Target memory contents if they are required for value calculations. +// +// The Value parameter here is the load address of the symbol for the +// relocation to be applied. For relocations which refer to symbols in the +// current object Value will be the LoadAddress of the section in which +// the symbol resides (RE.Addend provides additional information about the +// symbol location). For external symbols, Value will be the address of the +// symbol in the target address space. +void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE, + uint64_t Value) { + const SectionEntry &Section = Sections[RE.SectionID]; + return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend, + RE.SymOffset); +} void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section, - uint64_t Offset, - uint64_t Value, - uint32_t Type, - int64_t Addend) { + uint64_t Offset, uint64_t Value, + uint32_t Type, int64_t Addend, + uint64_t SymOffset) { switch (Arch) { case Triple::x86_64: - resolveX86_64Relocation(Section, Offset, Value, Type, Addend); + resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset); break; case Triple::x86: - resolveX86Relocation(Section, Offset, - (uint32_t)(Value & 0xffffffffL), Type, + resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type, (uint32_t)(Addend & 0xffffffffL)); break; - case Triple::arm: // Fall through. + case Triple::aarch64: + case Triple::aarch64_be: + resolveAArch64Relocation(Section, Offset, Value, Type, Addend); + break; + case Triple::arm: // Fall through. + case Triple::armeb: case Triple::thumb: - resolveARMRelocation(Section, Offset, - (uint32_t)(Value & 0xffffffffL), Type, + case Triple::thumbeb: + resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type, (uint32_t)(Addend & 0xffffffffL)); break; - case Triple::mips: // Fall through. + case Triple::mips: // Fall through. case Triple::mipsel: - resolveMIPSRelocation(Section, Offset, - (uint32_t)(Value & 0xffffffffL), Type, - (uint32_t)(Addend & 0xffffffffL)); + resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), + Type, (uint32_t)(Addend & 0xffffffffL)); break; - case Triple::ppc64: + case Triple::ppc64: // Fall through. + case Triple::ppc64le: resolvePPC64Relocation(Section, Offset, Value, Type, Addend); break; - default: llvm_unreachable("Unsupported CPU type!"); + case Triple::systemz: + resolveSystemZRelocation(Section, Offset, Value, Type, Addend); + break; + default: + llvm_unreachable("Unsupported CPU type!"); } } -void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel, - ObjectImage &Obj, - ObjSectionToIDMap &ObjSectionToID, - const SymbolTableMap &Symbols, - StubMap &Stubs) { +void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const { + return (void*)(Sections[SectionID].ObjAddress + Offset); +} - uint32_t RelType = (uint32_t)(Rel.Type & 0xffffffffL); - intptr_t Addend = (intptr_t)Rel.AdditionalInfo; - const SymbolRef &Symbol = Rel.Symbol; +void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) { + RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); +} + +relocation_iterator RuntimeDyldELF::processRelocationRef( + unsigned SectionID, relocation_iterator RelI, + const ObjectFile &Obj, + ObjSectionToIDMap &ObjSectionToID, + StubMap &Stubs) { + uint64_t RelType; + Check(RelI->getType(RelType)); + int64_t Addend; + Check(getELFRelocationAddend(*RelI, Addend)); + symbol_iterator Symbol = RelI->getSymbol(); // 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"); + if (Symbol != Obj.symbol_end()) + 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()); - SymbolRef::Type SymType; - Symbol.getType(SymType); - if (lsi != Symbols.end()) { - Value.SectionID = lsi->second.first; - Value.Addend = lsi->second.second; + SymbolRef::Type SymType = SymbolRef::ST_Unknown; + + // Search for the symbol in the global symbol table + RTDyldSymbolTable::const_iterator gsi = GlobalSymbolTable.end(); + if (Symbol != Obj.symbol_end()) { + gsi = GlobalSymbolTable.find(TargetName.data()); + Symbol->getType(SymType); + } + if (gsi != GlobalSymbolTable.end()) { + const auto &SymInfo = gsi->second; + Value.SectionID = SymInfo.getSectionID(); + Value.Offset = SymInfo.getOffset(); + Value.Addend = SymInfo.getOffset() + Addend; } 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 { - 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"); - // Default to 'true' in case isText fails (though it never does). - bool isCode = true; - si->isText(isCode); - Value.SectionID = findOrEmitSection(Obj, - (*si), - isCode, - ObjSectionToID); - Value.Addend = Addend; - break; - } - case SymbolRef::ST_Unknown: { - Value.SymbolName = TargetName.data(); - Value.Addend = Addend; - break; - } - default: - llvm_unreachable("Unresolved symbol type!"); - break; - } + 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.section_end()); + Symbol->getSection(si); + if (si == Obj.section_end()) + llvm_unreachable("Symbol section not found, bad object file format!"); + DEBUG(dbgs() << "\t\tThis is section symbol\n"); + bool isCode = si->isText(); + Value.SectionID = findOrEmitSection(Obj, (*si), isCode, ObjSectionToID); + Value.Addend = Addend; + break; + } + case SymbolRef::ST_Data: + case SymbolRef::ST_Unknown: { + Value.SymbolName = TargetName.data(); + Value.Addend = Addend; + + // Absolute relocations will have a zero symbol ID (STN_UNDEF), which + // will manifest here as a NULL symbol name. + // We can set this as a valid (but empty) symbol name, and rely + // on addRelocationForSymbol to handle this. + if (!Value.SymbolName) + Value.SymbolName = ""; + break; + } + default: + llvm_unreachable("Unresolved symbol type!"); + break; } } - DEBUG(dbgs() << "\t\tRel.SectionID: " << Rel.SectionID - << " Rel.Offset: " << Rel.Offset + + uint64_t Offset; + Check(RelI->getOffset(Offset)); + + DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << 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]; + if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be) && + (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26)) { + // This is an AArch64 branch relocation, need to use a stub function. + DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation."); + SectionEntry &Section = Sections[SectionID]; // Look for an existing stub. StubMap::const_iterator i = Stubs.find(Value); if (i != Stubs.end()) { - resolveRelocation(Section, Rel.Offset, - (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(Section, Rel.Offset, - (uint64_t)Section.Address + Section.StubOffset, + resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second, 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(Section, Rel.Offset, - (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); + uint8_t *StubTargetAddr = + createStubFunction(Section.Address + Section.StubOffset); + + RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.Address, + ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend); + RelocationEntry REmovk_g2(SectionID, StubTargetAddr - Section.Address + 4, + ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend); + RelocationEntry REmovk_g1(SectionID, StubTargetAddr - Section.Address + 8, + ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend); + RelocationEntry REmovk_g0(SectionID, + StubTargetAddr - Section.Address + 12, + ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend); if (Value.SymbolName) { - addRelocationForSymbol(REHi, Value.SymbolName); - addRelocationForSymbol(RELo, Value.SymbolName); + addRelocationForSymbol(REmovz_g3, Value.SymbolName); + addRelocationForSymbol(REmovk_g2, Value.SymbolName); + addRelocationForSymbol(REmovk_g1, Value.SymbolName); + addRelocationForSymbol(REmovk_g0, Value.SymbolName); } else { - addRelocationForSection(REHi, Value.SectionID); - addRelocationForSection(RELo, Value.SectionID); + addRelocationForSection(REmovz_g3, Value.SectionID); + addRelocationForSection(REmovk_g2, Value.SectionID); + addRelocationForSection(REmovk_g1, Value.SectionID); + addRelocationForSection(REmovk_g0, Value.SectionID); } - - resolveRelocation(Section, Rel.Offset, - (uint64_t)Section.Address + Section.StubOffset, - RelType, 0); + resolveRelocation(Section, Offset, + (uint64_t)Section.Address + Section.StubOffset, RelType, + 0); Section.StubOffset += getMaxStubSize(); } - } else if (Arch == Triple::ppc64) { + } else if (Arch == Triple::arm) { + if (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[SectionID]; + + // Look for an existing stub. + StubMap::const_iterator i = Stubs.find(Value); + if (i != Stubs.end()) { + resolveRelocation(Section, Offset, (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(SectionID, StubTargetAddr - Section.Address, + ELF::R_ARM_ABS32, Value.Addend); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + + resolveRelocation(Section, Offset, + (uint64_t)Section.Address + Section.StubOffset, RelType, + 0); + Section.StubOffset += getMaxStubSize(); + } + } else { + uint32_t *Placeholder = + reinterpret_cast(computePlaceholderAddress(SectionID, Offset)); + if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 || + RelType == ELF::R_ARM_ABS32) { + Value.Addend += *Placeholder; + } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) { + // See ELF for ARM documentation + Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12)); + } + processSimpleRelocation(SectionID, Offset, RelType, Value); + } + } else if ((Arch == Triple::mipsel || Arch == Triple::mips)) { + uint32_t *Placeholder = reinterpret_cast(computePlaceholderAddress(SectionID, Offset)); + if (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[SectionID]; + + // Extract the addend from the instruction. + // We shift up by two since the Value will be down shifted again + // when applying the relocation. + uint32_t Addend = ((*Placeholder) & 0x03ffffff) << 2; + + Value.Addend += Addend; + + // Look up for existing stub. + StubMap::const_iterator i = Stubs.find(Value); + if (i != Stubs.end()) { + RelocationEntry RE(SectionID, Offset, RelType, i->second); + addRelocationForSection(RE, SectionID); + 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(SectionID, StubTargetAddr - Section.Address, + ELF::R_MIPS_HI16, Value.Addend); + RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4, + ELF::R_MIPS_LO16, Value.Addend); + + if (Value.SymbolName) { + addRelocationForSymbol(REHi, Value.SymbolName); + addRelocationForSymbol(RELo, Value.SymbolName); + } + else { + addRelocationForSection(REHi, Value.SectionID); + addRelocationForSection(RELo, Value.SectionID); + } + + RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset); + addRelocationForSection(RE, SectionID); + Section.StubOffset += getMaxStubSize(); + } + } else { + if (RelType == ELF::R_MIPS_HI16) + Value.Addend += ((*Placeholder) & 0x0000ffff) << 16; + else if (RelType == ELF::R_MIPS_LO16) + Value.Addend += ((*Placeholder) & 0x0000ffff); + else if (RelType == ELF::R_MIPS_32) + Value.Addend += *Placeholder; + processSimpleRelocation(SectionID, Offset, RelType, Value); + } + } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) { if (RelType == ELF::R_PPC64_REL24) { + // Determine ABI variant in use for this object. + unsigned AbiVariant; + Obj.getPlatformFlags(AbiVariant); + AbiVariant &= ELF::EF_PPC64_ABI; // A PPC branch relocation will need a stub function if the target is // an external symbol (Symbol::ST_Unknown) or if the target address // is not within the signed 24-bits branch address. - SectionEntry &Section = Sections[Rel.SectionID]; - uint8_t *Target = Section.Address + Rel.Offset; + SectionEntry &Section = Sections[SectionID]; + uint8_t *Target = Section.Address + Offset; bool RangeOverflow = false; if (SymType != SymbolRef::ST_Unknown) { - // A function call may points to the .opd entry, so the final symbol value - // in calculated based in the relocation values in .opd section. - findOPDEntrySection(Obj, ObjSectionToID, Value); + if (AbiVariant != 2) { + // In the ELFv1 ABI, a function call may point to the .opd entry, + // so the final symbol value is calculated based on the relocation + // values in the .opd section. + findOPDEntrySection(Obj, ObjSectionToID, Value); + } else { + // In the ELFv2 ABI, a function symbol may provide a local entry + // point, which must be used for direct calls. + uint8_t SymOther; + Symbol->getOther(SymOther); + Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther); + } uint8_t *RelocTarget = Sections[Value.SectionID].Address + Value.Addend; int32_t delta = static_cast(Target - RelocTarget); // If it is within 24-bits branch range, just set the branch target if (SignExtend32<24>(delta) == delta) { - RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend); + RelocationEntry RE(SectionID, Offset, RelType, Value.Addend); if (Value.SymbolName) addRelocationForSymbol(RE, Value.SymbolName); else @@ -747,88 +1092,347 @@ void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel, RangeOverflow = true; } } - if (SymType == SymbolRef::ST_Unknown || RangeOverflow == true) { + if (SymType == SymbolRef::ST_Unknown || RangeOverflow) { // It is an external symbol (SymbolRef::ST_Unknown) or within a range // larger than 24-bits. StubMap::const_iterator i = Stubs.find(Value); if (i != Stubs.end()) { // Symbol function stub already created, just relocate to it - resolveRelocation(Section, Rel.Offset, + resolveRelocation(Section, Offset, (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, + uint8_t *StubTargetAddr = + createStubFunction(Section.Address + Section.StubOffset, + AbiVariant); + RelocationEntry RE(SectionID, StubTargetAddr - Section.Address, ELF::R_PPC64_ADDR64, Value.Addend); // Generates the 64-bits address loads as exemplified in section - // 4.5.1 in PPC64 ELF ABI. - RelocationEntry REhst(Rel.SectionID, - StubTargetAddr - Section.Address + 2, + // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to + // apply to the low part of the instructions, so we have to update + // the offset according to the target endianness. + uint64_t StubRelocOffset = StubTargetAddr - Section.Address; + if (!IsTargetLittleEndian) + StubRelocOffset += 2; + + RelocationEntry REhst(SectionID, StubRelocOffset + 0, ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend); - RelocationEntry REhr(Rel.SectionID, - StubTargetAddr - Section.Address + 6, + RelocationEntry REhr(SectionID, StubRelocOffset + 4, ELF::R_PPC64_ADDR16_HIGHER, Value.Addend); - RelocationEntry REh(Rel.SectionID, - StubTargetAddr - Section.Address + 14, + RelocationEntry REh(SectionID, StubRelocOffset + 12, ELF::R_PPC64_ADDR16_HI, Value.Addend); - RelocationEntry REl(Rel.SectionID, - StubTargetAddr - Section.Address + 18, + RelocationEntry REl(SectionID, StubRelocOffset + 16, ELF::R_PPC64_ADDR16_LO, Value.Addend); if (Value.SymbolName) { addRelocationForSymbol(REhst, Value.SymbolName); - addRelocationForSymbol(REhr, Value.SymbolName); - addRelocationForSymbol(REh, Value.SymbolName); - addRelocationForSymbol(REl, Value.SymbolName); + addRelocationForSymbol(REhr, Value.SymbolName); + addRelocationForSymbol(REh, Value.SymbolName); + addRelocationForSymbol(REl, Value.SymbolName); } else { addRelocationForSection(REhst, Value.SectionID); - addRelocationForSection(REhr, Value.SectionID); - addRelocationForSection(REh, Value.SectionID); - addRelocationForSection(REl, Value.SectionID); + addRelocationForSection(REhr, Value.SectionID); + addRelocationForSection(REh, Value.SectionID); + addRelocationForSection(REl, Value.SectionID); } - resolveRelocation(Section, Rel.Offset, + resolveRelocation(Section, Offset, (uint64_t)Section.Address + Section.StubOffset, RelType, 0); - if (SymType == SymbolRef::ST_Unknown) - // Restore the TOC for external calls - writeInt32BE(Target+4, 0xE8410028); // ld r2,40(r1) Section.StubOffset += getMaxStubSize(); } + if (SymType == SymbolRef::ST_Unknown) { + // Restore the TOC for external calls + if (AbiVariant == 2) + writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1) + else + writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1) + } + } + } else if (RelType == ELF::R_PPC64_TOC16 || + RelType == ELF::R_PPC64_TOC16_DS || + RelType == ELF::R_PPC64_TOC16_LO || + RelType == ELF::R_PPC64_TOC16_LO_DS || + RelType == ELF::R_PPC64_TOC16_HI || + RelType == ELF::R_PPC64_TOC16_HA) { + // These relocations are supposed to subtract the TOC address from + // the final value. This does not fit cleanly into the RuntimeDyld + // scheme, since there may be *two* sections involved in determining + // the relocation value (the section of the symbol refered to by the + // relocation, and the TOC section associated with the current module). + // + // Fortunately, these relocations are currently only ever generated + // refering to symbols that themselves reside in the TOC, which means + // that the two sections are actually the same. Thus they cancel out + // and we can immediately resolve the relocation right now. + switch (RelType) { + case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break; + case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break; + case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break; + case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break; + case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break; + case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break; + default: llvm_unreachable("Wrong relocation type."); } + + RelocationValueRef TOCValue; + findPPC64TOCSection(Obj, ObjSectionToID, TOCValue); + if (Value.SymbolName || Value.SectionID != TOCValue.SectionID) + llvm_unreachable("Unsupported TOC relocation."); + Value.Addend -= TOCValue.Addend; + resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0); } else { - RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend); - // Extra check to avoid relocation againt empty symbols (usually - // the R_PPC64_TOC). - if (Value.SymbolName && !TargetName.empty()) + // There are two ways to refer to the TOC address directly: either + // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are + // ignored), or via any relocation that refers to the magic ".TOC." + // symbols (in which case the addend is respected). + if (RelType == ELF::R_PPC64_TOC) { + RelType = ELF::R_PPC64_ADDR64; + findPPC64TOCSection(Obj, ObjSectionToID, Value); + } else if (TargetName == ".TOC.") { + findPPC64TOCSection(Obj, ObjSectionToID, Value); + Value.Addend += Addend; + } + + RelocationEntry RE(SectionID, Offset, RelType, Value.Addend); + + if (Value.SymbolName) addRelocationForSymbol(RE, Value.SymbolName); else addRelocationForSection(RE, Value.SectionID); } - } else { - RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend); - if (Value.SymbolName) - addRelocationForSymbol(RE, Value.SymbolName); + } else if (Arch == Triple::systemz && + (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) { + // Create function stubs for both PLT and GOT references, regardless of + // whether the GOT reference is to data or code. The stub contains the + // full address of the symbol, as needed by GOT references, and the + // executable part only adds an overhead of 8 bytes. + // + // We could try to conserve space by allocating the code and data + // parts of the stub separately. However, as things stand, we allocate + // a stub for every relocation, so using a GOT in JIT code should be + // no less space efficient than using an explicit constant pool. + DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation."); + SectionEntry &Section = Sections[SectionID]; + + // Look for an existing stub. + StubMap::const_iterator i = Stubs.find(Value); + uintptr_t StubAddress; + if (i != Stubs.end()) { + StubAddress = uintptr_t(Section.Address) + i->second; + DEBUG(dbgs() << " Stub function found\n"); + } else { + // Create a new stub function. + DEBUG(dbgs() << " Create a new stub function\n"); + + uintptr_t BaseAddress = uintptr_t(Section.Address); + uintptr_t StubAlignment = getStubAlignment(); + StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) & + -StubAlignment; + unsigned StubOffset = StubAddress - BaseAddress; + + Stubs[Value] = StubOffset; + createStubFunction((uint8_t *)StubAddress); + RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64, + Value.Offset); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + Section.StubOffset = StubOffset + getMaxStubSize(); + } + + if (RelType == ELF::R_390_GOTENT) + resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL, + Addend); else - addRelocationForSection(RE, Value.SectionID); + resolveRelocation(Section, Offset, StubAddress, RelType, Addend); + } else if (Arch == Triple::x86_64) { + if (RelType == ELF::R_X86_64_PLT32) { + // The way the PLT relocations normally work is that the linker allocates + // the + // PLT and this relocation makes a PC-relative call into the PLT. The PLT + // entry will then jump to an address provided by the GOT. On first call, + // the + // GOT address will point back into PLT code that resolves the symbol. After + // the first call, the GOT entry points to the actual function. + // + // For local functions we're ignoring all of that here and just replacing + // the PLT32 relocation type with PC32, which will translate the relocation + // into a PC-relative call directly to the function. For external symbols we + // can't be sure the function will be within 2^32 bytes of the call site, so + // we need to create a stub, which calls into the GOT. This case is + // equivalent to the usual PLT implementation except that we use the stub + // mechanism in RuntimeDyld (which puts stubs at the end of the section) + // rather than allocating a PLT section. + if (Value.SymbolName) { + // This is a call to an external function. + // Look for an existing stub. + SectionEntry &Section = Sections[SectionID]; + StubMap::const_iterator i = Stubs.find(Value); + uintptr_t StubAddress; + if (i != Stubs.end()) { + StubAddress = uintptr_t(Section.Address) + i->second; + DEBUG(dbgs() << " Stub function found\n"); + } else { + // Create a new stub function (equivalent to a PLT entry). + DEBUG(dbgs() << " Create a new stub function\n"); + + uintptr_t BaseAddress = uintptr_t(Section.Address); + uintptr_t StubAlignment = getStubAlignment(); + StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) & + -StubAlignment; + unsigned StubOffset = StubAddress - BaseAddress; + Stubs[Value] = StubOffset; + createStubFunction((uint8_t *)StubAddress); + + // Bump our stub offset counter + Section.StubOffset = StubOffset + getMaxStubSize(); + + // Allocate a GOT Entry + uint64_t GOTOffset = allocateGOTEntries(SectionID, 1); + + // The load of the GOT address has an addend of -4 + resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4); + + // Fill in the value of the symbol we're targeting into the GOT + addRelocationForSymbol(computeGOTOffsetRE(SectionID,GOTOffset,0,ELF::R_X86_64_64), + Value.SymbolName); + } + + // Make the target call a call into the stub table. + resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32, + Addend); + } else { + RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend, + Value.Offset); + addRelocationForSection(RE, Value.SectionID); + } + } else if (RelType == ELF::R_X86_64_GOTPCREL) { + uint64_t GOTOffset = allocateGOTEntries(SectionID, 1); + resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend); + + // Fill in the value of the symbol we're targeting into the GOT + RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + } else if (RelType == ELF::R_X86_64_PC32) { + Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset)); + processSimpleRelocation(SectionID, Offset, RelType, Value); + } else if (RelType == ELF::R_X86_64_PC64) { + Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset)); + processSimpleRelocation(SectionID, Offset, RelType, Value); + } else { + processSimpleRelocation(SectionID, Offset, RelType, Value); + } + } else { + if (Arch == Triple::x86) { + Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset)); + } + processSimpleRelocation(SectionID, Offset, RelType, Value); } + return ++RelI; } -unsigned RuntimeDyldELF::getCommonSymbolAlignment(const SymbolRef &Sym) { - // In ELF, the value of an SHN_COMMON symbol is its alignment requirement. - uint64_t Align; - Check(Sym.getValue(Align)); - return Align; +size_t RuntimeDyldELF::getGOTEntrySize() { + // We don't use the GOT in all of these cases, but it's essentially free + // to put them all here. + size_t Result = 0; + switch (Arch) { + case Triple::x86_64: + case Triple::aarch64: + case Triple::aarch64_be: + case Triple::ppc64: + case Triple::ppc64le: + case Triple::systemz: + Result = sizeof(uint64_t); + break; + case Triple::x86: + case Triple::arm: + case Triple::thumb: + case Triple::mips: + case Triple::mipsel: + Result = sizeof(uint32_t); + break; + default: + llvm_unreachable("Unsupported CPU type!"); + } + return Result; } -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; +uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned SectionID, unsigned no) +{ + (void)SectionID; // The GOT Section is the same for all section in the object file + if (GOTSectionID == 0) { + GOTSectionID = Sections.size(); + // Reserve a section id. We'll allocate the section later + // once we know the total size + Sections.push_back(SectionEntry(".got", 0, 0, 0)); + } + uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize(); + CurrentGOTIndex += no; + return StartOffset; +} + +void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, uint64_t GOTOffset) +{ + // Fill in the relative address of the GOT Entry into the stub + RelocationEntry GOTRE(SectionID, Offset, ELF::R_X86_64_PC32, GOTOffset); + addRelocationForSection(GOTRE, GOTSectionID); +} + +RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(unsigned SectionID, uint64_t GOTOffset, uint64_t SymbolOffset, + uint32_t Type) +{ + (void)SectionID; // The GOT Section is the same for all section in the object file + return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset); +} + +void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj, + ObjSectionToIDMap &SectionMap) { + // If necessary, allocate the global offset table + if (GOTSectionID != 0) { + // Allocate memory for the section + size_t TotalSize = CurrentGOTIndex * getGOTEntrySize(); + uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(), + GOTSectionID, ".got", false); + if (!Addr) + report_fatal_error("Unable to allocate memory for GOT!"); + + Sections[GOTSectionID] = SectionEntry(".got", Addr, TotalSize, 0); + + if (Checker) + Checker->registerSection(Obj.getFileName(), GOTSectionID); + + // For now, initialize all GOT entries to zero. We'll fill them in as + // needed when GOT-based relocations are applied. + memset(Addr, 0, TotalSize); + } + + // Look for and record the EH frame section. + ObjSectionToIDMap::iterator i, e; + for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) { + const SectionRef &Section = i->first; + StringRef Name; + Section.getName(Name); + if (Name == ".eh_frame") { + UnregisteredEHFrameSections.push_back(i->second); + break; + } + } + + GOTSectionID = 0; + CurrentGOTIndex = 0; +} + +bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const { + return Obj.isELF(); } + } // namespace llvm