X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FELFObjectWriter.cpp;h=0b97f2700bef0028374744645cb8d41a8aa7ef68;hb=50e75bfc29269def44981ab5f109334d95f55007;hp=cb8b4e14b6fad7b6e575a113a5318ba36c24abd4;hpb=e8526d030f2cf8cc79f2d923274944cb0fa9c4eb;p=oota-llvm.git diff --git a/lib/MC/ELFObjectWriter.cpp b/lib/MC/ELFObjectWriter.cpp index cb8b4e14b6f..0b97f2700be 100644 --- a/lib/MC/ELFObjectWriter.cpp +++ b/lib/MC/ELFObjectWriter.cpp @@ -11,33 +11,334 @@ // //===----------------------------------------------------------------------===// -#include "ELFObjectWriter.h" +#include "llvm/MC/MCELFObjectWriter.h" +#include "llvm/ADT/OwningPtr.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/SmallString.h" #include "llvm/ADT/StringMap.h" -#include "llvm/ADT/Twine.h" #include "llvm/MC/MCAsmBackend.h" #include "llvm/MC/MCAsmLayout.h" +#include "llvm/MC/MCAssembler.h" #include "llvm/MC/MCContext.h" +#include "llvm/MC/MCELF.h" +#include "llvm/MC/MCELFSymbolFlags.h" #include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCFixupKindInfo.h" +#include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSectionELF.h" #include "llvm/MC/MCValue.h" #include "llvm/Support/Debug.h" -#include "llvm/Support/ErrorHandling.h" #include "llvm/Support/ELF.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/ADT/StringSwitch.h" - -#include "../Target/Mips/MCTargetDesc/MipsFixupKinds.h" -#include "../Target/ARM/MCTargetDesc/ARMFixupKinds.h" -#include "../Target/PowerPC/MCTargetDesc/PPCFixupKinds.h" - +#include "llvm/Support/ErrorHandling.h" #include using namespace llvm; #undef DEBUG_TYPE #define DEBUG_TYPE "reloc-info" +namespace { +class ELFObjectWriter : public MCObjectWriter { + protected: + + static bool isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind); + static bool RelocNeedsGOT(MCSymbolRefExpr::VariantKind Variant); + static uint64_t SymbolValue(MCSymbolData &Data, const MCAsmLayout &Layout); + static bool isInSymtab(const MCAssembler &Asm, const MCSymbolData &Data, + bool Used, bool Renamed); + static bool isLocal(const MCSymbolData &Data, bool isSignature, + bool isUsedInReloc); + static bool IsELFMetaDataSection(const MCSectionData &SD); + static uint64_t DataSectionSize(const MCSectionData &SD); + static uint64_t GetSectionFileSize(const MCAsmLayout &Layout, + const MCSectionData &SD); + static uint64_t GetSectionAddressSize(const MCAsmLayout &Layout, + const MCSectionData &SD); + + void WriteDataSectionData(MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCSectionELF &Section); + + /*static bool isFixupKindX86RIPRel(unsigned Kind) { + return Kind == X86::reloc_riprel_4byte || + Kind == X86::reloc_riprel_4byte_movq_load; + }*/ + + /// ELFSymbolData - Helper struct for containing some precomputed + /// information on symbols. + struct ELFSymbolData { + MCSymbolData *SymbolData; + uint64_t StringIndex; + uint32_t SectionIndex; + + // Support lexicographic sorting. + bool operator<(const ELFSymbolData &RHS) const { + if (MCELF::GetType(*SymbolData) == ELF::STT_FILE) + return true; + if (MCELF::GetType(*RHS.SymbolData) == ELF::STT_FILE) + return false; + return SymbolData->getSymbol().getName() < + RHS.SymbolData->getSymbol().getName(); + } + }; + + /// The target specific ELF writer instance. + llvm::OwningPtr TargetObjectWriter; + + SmallPtrSet UsedInReloc; + SmallPtrSet WeakrefUsedInReloc; + DenseMap Renames; + + llvm::DenseMap > Relocations; + DenseMap SectionStringTableIndex; + + /// @} + /// @name Symbol Table Data + /// @{ + + SmallString<256> StringTable; + std::vector LocalSymbolData; + std::vector ExternalSymbolData; + std::vector UndefinedSymbolData; + + /// @} + + bool NeedsGOT; + + bool NeedsSymtabShndx; + + // This holds the symbol table index of the last local symbol. + unsigned LastLocalSymbolIndex; + // This holds the .strtab section index. + unsigned StringTableIndex; + // This holds the .symtab section index. + unsigned SymbolTableIndex; + + unsigned ShstrtabIndex; + + + const MCSymbol *SymbolToReloc(const MCAssembler &Asm, + const MCValue &Target, + const MCFragment &F, + const MCFixup &Fixup, + bool IsPCRel) const; + + // TargetObjectWriter wrappers. + const MCSymbol *ExplicitRelSym(const MCAssembler &Asm, + const MCValue &Target, + const MCFragment &F, + const MCFixup &Fixup, + bool IsPCRel) const { + return TargetObjectWriter->ExplicitRelSym(Asm, Target, F, Fixup, IsPCRel); + } + const MCSymbol *undefinedExplicitRelSym(const MCValue &Target, + const MCFixup &Fixup, + bool IsPCRel) const { + return TargetObjectWriter->undefinedExplicitRelSym(Target, Fixup, + IsPCRel); + } + + bool is64Bit() const { return TargetObjectWriter->is64Bit(); } + bool hasRelocationAddend() const { + return TargetObjectWriter->hasRelocationAddend(); + } + unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup, + bool IsPCRel, bool IsRelocWithSymbol, + int64_t Addend) const { + return TargetObjectWriter->GetRelocType(Target, Fixup, IsPCRel, + IsRelocWithSymbol, Addend); + } + + public: + ELFObjectWriter(MCELFObjectTargetWriter *MOTW, + raw_ostream &_OS, bool IsLittleEndian) + : MCObjectWriter(_OS, IsLittleEndian), + TargetObjectWriter(MOTW), + NeedsGOT(false), NeedsSymtabShndx(false){ + } + + virtual ~ELFObjectWriter(); + + void WriteWord(uint64_t W) { + if (is64Bit()) + Write64(W); + else + Write32(W); + } + + void StringLE16(char *buf, uint16_t Value) { + buf[0] = char(Value >> 0); + buf[1] = char(Value >> 8); + } + + void StringLE32(char *buf, uint32_t Value) { + StringLE16(buf, uint16_t(Value >> 0)); + StringLE16(buf + 2, uint16_t(Value >> 16)); + } + + void StringLE64(char *buf, uint64_t Value) { + StringLE32(buf, uint32_t(Value >> 0)); + StringLE32(buf + 4, uint32_t(Value >> 32)); + } + + void StringBE16(char *buf ,uint16_t Value) { + buf[0] = char(Value >> 8); + buf[1] = char(Value >> 0); + } + + void StringBE32(char *buf, uint32_t Value) { + StringBE16(buf, uint16_t(Value >> 16)); + StringBE16(buf + 2, uint16_t(Value >> 0)); + } + + void StringBE64(char *buf, uint64_t Value) { + StringBE32(buf, uint32_t(Value >> 32)); + StringBE32(buf + 4, uint32_t(Value >> 0)); + } + + void String8(MCDataFragment &F, uint8_t Value) { + char buf[1]; + buf[0] = Value; + F.getContents().append(&buf[0], &buf[1]); + } + + void String16(MCDataFragment &F, uint16_t Value) { + char buf[2]; + if (isLittleEndian()) + StringLE16(buf, Value); + else + StringBE16(buf, Value); + F.getContents().append(&buf[0], &buf[2]); + } + + void String32(MCDataFragment &F, uint32_t Value) { + char buf[4]; + if (isLittleEndian()) + StringLE32(buf, Value); + else + StringBE32(buf, Value); + F.getContents().append(&buf[0], &buf[4]); + } + + void String64(MCDataFragment &F, uint64_t Value) { + char buf[8]; + if (isLittleEndian()) + StringLE64(buf, Value); + else + StringBE64(buf, Value); + F.getContents().append(&buf[0], &buf[8]); + } + + void WriteHeader(const MCAssembler &Asm, + uint64_t SectionDataSize, + unsigned NumberOfSections); + + void WriteSymbolEntry(MCDataFragment *SymtabF, + MCDataFragment *ShndxF, + uint64_t name, uint8_t info, + uint64_t value, uint64_t size, + uint8_t other, uint32_t shndx, + bool Reserved); + + void WriteSymbol(MCDataFragment *SymtabF, MCDataFragment *ShndxF, + ELFSymbolData &MSD, + const MCAsmLayout &Layout); + + typedef DenseMap SectionIndexMapTy; + void WriteSymbolTable(MCDataFragment *SymtabF, + MCDataFragment *ShndxF, + const MCAssembler &Asm, + const MCAsmLayout &Layout, + const SectionIndexMapTy &SectionIndexMap); + + virtual void RecordRelocation(const MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCFragment *Fragment, + const MCFixup &Fixup, + MCValue Target, uint64_t &FixedValue); + + uint64_t getSymbolIndexInSymbolTable(const MCAssembler &Asm, + const MCSymbol *S); + + // Map from a group section to the signature symbol + typedef DenseMap GroupMapTy; + // Map from a signature symbol to the group section + typedef DenseMap RevGroupMapTy; + // Map from a section to the section with the relocations + typedef DenseMap RelMapTy; + // Map from a section to its offset + typedef DenseMap SectionOffsetMapTy; + + /// ComputeSymbolTable - Compute the symbol table data + /// + /// \param Asm - The assembler. + /// \param SectionIndexMap - Maps a section to its index. + /// \param RevGroupMap - Maps a signature symbol to the group section. + /// \param NumRegularSections - Number of non-relocation sections. + void ComputeSymbolTable(MCAssembler &Asm, + const SectionIndexMapTy &SectionIndexMap, + RevGroupMapTy RevGroupMap, + unsigned NumRegularSections); + + void ComputeIndexMap(MCAssembler &Asm, + SectionIndexMapTy &SectionIndexMap, + const RelMapTy &RelMap); + + void CreateRelocationSections(MCAssembler &Asm, MCAsmLayout &Layout, + RelMapTy &RelMap); + + void WriteRelocations(MCAssembler &Asm, MCAsmLayout &Layout, + const RelMapTy &RelMap); + + void CreateMetadataSections(MCAssembler &Asm, MCAsmLayout &Layout, + SectionIndexMapTy &SectionIndexMap, + const RelMapTy &RelMap); + + // Create the sections that show up in the symbol table. Currently + // those are the .note.GNU-stack section and the group sections. + void CreateIndexedSections(MCAssembler &Asm, MCAsmLayout &Layout, + GroupMapTy &GroupMap, + RevGroupMapTy &RevGroupMap, + SectionIndexMapTy &SectionIndexMap, + const RelMapTy &RelMap); + + virtual void ExecutePostLayoutBinding(MCAssembler &Asm, + const MCAsmLayout &Layout); + + void WriteSectionHeader(MCAssembler &Asm, const GroupMapTy &GroupMap, + const MCAsmLayout &Layout, + const SectionIndexMapTy &SectionIndexMap, + const SectionOffsetMapTy &SectionOffsetMap); + + void ComputeSectionOrder(MCAssembler &Asm, + std::vector &Sections); + + void WriteSecHdrEntry(uint32_t Name, uint32_t Type, uint64_t Flags, + uint64_t Address, uint64_t Offset, + uint64_t Size, uint32_t Link, uint32_t Info, + uint64_t Alignment, uint64_t EntrySize); + + void WriteRelocationsFragment(const MCAssembler &Asm, + MCDataFragment *F, + const MCSectionData *SD); + + virtual bool + IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, + const MCSymbolData &DataA, + const MCFragment &FB, + bool InSet, + bool IsPCRel) const; + + virtual void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout); + void WriteSection(MCAssembler &Asm, + const SectionIndexMapTy &SectionIndexMap, + uint32_t GroupSymbolIndex, + uint64_t Offset, uint64_t Size, uint64_t Alignment, + const MCSectionELF &Section); + }; +} + bool ELFObjectWriter::isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind) { const MCFixupKindInfo &FKI = Asm.getBackend().getFixupKindInfo((MCFixupKind) Kind); @@ -70,7 +371,8 @@ ELFObjectWriter::~ELFObjectWriter() {} // Emit the ELF header. -void ELFObjectWriter::WriteHeader(uint64_t SectionDataSize, +void ELFObjectWriter::WriteHeader(const MCAssembler &Asm, + uint64_t SectionDataSize, unsigned NumberOfSections) { // ELF Header // ---------- @@ -108,7 +410,7 @@ void ELFObjectWriter::WriteHeader(uint64_t SectionDataSize, sizeof(ELF::Elf32_Ehdr))); // e_shoff = sec hdr table off in bytes // e_flags = whatever the target wants - Write32(getEFlags()); + Write32(Asm.getELFHeaderEFlags()); // e_ehsize = ELF header size Write16(is64Bit() ? sizeof(ELF::Elf64_Ehdr) : sizeof(ELF::Elf32_Ehdr)); @@ -244,12 +546,17 @@ void ELFObjectWriter::WriteSymbol(MCDataFragment *SymtabF, bool IsReserved = Data.isCommon() || Data.getSymbol().isAbsolute() || Data.getSymbol().isVariable(); + // Binding and Type share the same byte as upper and lower nibbles uint8_t Binding = MCELF::GetBinding(OrigData); - uint8_t Visibility = MCELF::GetVisibility(OrigData); uint8_t Type = MCELF::GetType(Data); - uint8_t Info = (Binding << ELF_STB_Shift) | (Type << ELF_STT_Shift); - uint8_t Other = Visibility; + + // Other and Visibility share the same byte with Visability using the lower + // 2 bits + uint8_t Visibility = MCELF::GetVisibility(OrigData); + uint8_t Other = MCELF::getOther(OrigData) << + (ELF_Other_Shift - ELF_STV_Shift); + Other |= Visibility; uint64_t Value = SymbolValue(Data, Layout); uint64_t Size = 0; @@ -329,7 +636,7 @@ void ELFObjectWriter::WriteSymbolTable(MCDataFragment *SymtabF, const MCSymbol *ELFObjectWriter::SymbolToReloc(const MCAssembler &Asm, const MCValue &Target, - const MCFragment &F, + const MCFragment &F, const MCFixup &Fixup, bool IsPCRel) const { const MCSymbol &Symbol = Target.getSymA()->getSymbol(); @@ -340,7 +647,7 @@ const MCSymbol *ELFObjectWriter::SymbolToReloc(const MCAssembler &Asm, if (ASymbol.isUndefined()) { if (Renamed) return Renamed; - return &ASymbol; + return undefinedExplicitRelSym(Target, Fixup, IsPCRel); } if (SD.isExternal()) { @@ -422,10 +729,13 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, MCSymbolData &SD = Asm.getSymbolData(ASymbol); MCFragment *F = SD.getFragment(); - Index = F->getParent()->getOrdinal() + 1; - - // Offset of the symbol in the section - Value += Layout.getSymbolOffset(&SD); + if (F) { + Index = F->getParent()->getOrdinal() + 1; + // Offset of the symbol in the section + Value += Layout.getSymbolOffset(&SD); + } else { + Index = 0; + } } else { if (Asm.getSymbolData(Symbol).getFlags() & ELF_Other_Weakref) WeakrefUsedInReloc.insert(RelocSymbol); @@ -434,8 +744,7 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, Index = -1; } Addend = Value; - // Compensate for the addend on i386. - if (is64Bit()) + if (hasRelocationAddend()) Value = 0; } @@ -450,7 +759,8 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, uint64_t RelocOffset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset(); - adjustFixupOffset(Fixup, RelocOffset); + // FIXME: no tests cover this. Is adjustFixupOffset dead code? + TargetObjectWriter->adjustFixupOffset(Fixup, RelocOffset); if (!hasRelocationAddend()) Addend = 0; @@ -460,7 +770,7 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, else assert(isInt<32>(Addend)); - ELFRelocationEntry ERE(RelocOffset, Index, Type, RelocSymbol, Addend); + ELFRelocationEntry ERE(RelocOffset, Index, Type, RelocSymbol, Addend, Fixup); Relocations[Fragment->getParent()].push_back(ERE); } @@ -559,7 +869,7 @@ void ELFObjectWriter::ComputeSymbolTable(MCAssembler &Asm, // FIXME: Is this the correct place to do this? // FIXME: Why is an undefined reference to _GLOBAL_OFFSET_TABLE_ needed? if (NeedsGOT) { - llvm::StringRef Name = "_GLOBAL_OFFSET_TABLE_"; + StringRef Name = "_GLOBAL_OFFSET_TABLE_"; MCSymbol *Sym = Asm.getContext().GetOrCreateSymbol(Name); MCSymbolData &Data = Asm.getOrCreateSymbolData(*Sym); Data.setExternal(true); @@ -746,8 +1056,10 @@ void ELFObjectWriter::WriteRelocationsFragment(const MCAssembler &Asm, MCDataFragment *F, const MCSectionData *SD) { std::vector &Relocs = Relocations[SD]; - // sort by the r_offset just like gnu as does - array_pod_sort(Relocs.begin(), Relocs.end()); + + // Sort the relocation entries. Most targets just sort by r_offset, but some + // (e.g., MIPS) have additional constraints. + TargetObjectWriter->sortRelocs(Asm, Relocs); for (unsigned i = 0, e = Relocs.size(); i != e; ++i) { ELFRelocationEntry entry = Relocs[e - i - 1]; @@ -760,11 +1072,19 @@ void ELFObjectWriter::WriteRelocationsFragment(const MCAssembler &Asm, entry.Index += LocalSymbolData.size(); if (is64Bit()) { String64(*F, entry.r_offset); + if (TargetObjectWriter->isN64()) { + String32(*F, entry.Index); - struct ELF::Elf64_Rela ERE64; - ERE64.setSymbolAndType(entry.Index, entry.Type); - String64(*F, ERE64.r_info); - + String8(*F, TargetObjectWriter->getRSsym(entry.Type)); + String8(*F, TargetObjectWriter->getRType3(entry.Type)); + String8(*F, TargetObjectWriter->getRType2(entry.Type)); + String8(*F, TargetObjectWriter->getRType(entry.Type)); + } + else { + struct ELF::Elf64_Rela ERE64; + ERE64.setSymbolAndType(entry.Index, entry.Type); + String64(*F, ERE64.r_info); + } if (hasRelocationAddend()) String64(*F, entry.r_addend); } else { @@ -870,7 +1190,7 @@ void ELFObjectWriter::CreateMetadataSections(MCAssembler &Asm, // The first entry of a string table holds a null character so skip // section 0. uint64_t Index = 1; - F->getContents() += '\x00'; + F->getContents().push_back('\x00'); for (unsigned int I = 0, E = Sections.size(); I != E; ++I) { const MCSectionELF &Section = *Sections[I]; @@ -888,8 +1208,8 @@ void ELFObjectWriter::CreateMetadataSections(MCAssembler &Asm, SectionStringTableIndex[&Section] = Index; Index += Name.size() + 1; - F->getContents() += Name; - F->getContents() += '\x00'; + F->getContents().append(Name.begin(), Name.end()); + F->getContents().push_back('\x00'); } } @@ -1003,6 +1323,8 @@ void ELFObjectWriter::WriteSection(MCAssembler &Asm, case ELF::SHT_FINI_ARRAY: case ELF::SHT_PREINIT_ARRAY: case ELF::SHT_X86_64_UNWIND: + case ELF::SHT_MIPS_REGINFO: + case ELF::SHT_MIPS_OPTIONS: // Nothing to do. break; @@ -1016,6 +1338,24 @@ void ELFObjectWriter::WriteSection(MCAssembler &Asm, break; } + if (TargetObjectWriter->getEMachine() == ELF::EM_ARM && + Section.getType() == ELF::SHT_ARM_EXIDX) { + StringRef SecName(Section.getSectionName()); + if (SecName == ".ARM.exidx") { + sh_link = SectionIndexMap.lookup( + Asm.getContext().getELFSection(".text", + ELF::SHT_PROGBITS, + ELF::SHF_EXECINSTR | ELF::SHF_ALLOC, + SectionKind::getText())); + } else if (SecName.startswith(".ARM.exidx")) { + sh_link = SectionIndexMap.lookup( + Asm.getContext().getELFSection(SecName.substr(sizeof(".ARM.exidx") - 1), + ELF::SHT_PROGBITS, + ELF::SHF_EXECINSTR | ELF::SHF_ALLOC, + SectionKind::getText())); + } + } + WriteSecHdrEntry(SectionStringTableIndex[&Section], Section.getType(), Section.getFlags(), 0, Offset, Size, sh_link, sh_info, Alignment, Section.getEntrySize()); @@ -1054,21 +1394,17 @@ uint64_t ELFObjectWriter::GetSectionAddressSize(const MCAsmLayout &Layout, void ELFObjectWriter::WriteDataSectionData(MCAssembler &Asm, const MCAsmLayout &Layout, const MCSectionELF &Section) { - uint64_t FileOff = OS.tell(); const MCSectionData &SD = Asm.getOrCreateSectionData(Section); - uint64_t Padding = OffsetToAlignment(FileOff, SD.getAlignment()); + uint64_t Padding = OffsetToAlignment(OS.tell(), SD.getAlignment()); WriteZeros(Padding); - FileOff += Padding; - - FileOff += GetSectionFileSize(Layout, SD); if (IsELFMetaDataSection(SD)) { for (MCSectionData::const_iterator i = SD.begin(), e = SD.end(); i != e; ++i) { const MCFragment &F = *i; assert(F.getKind() == MCFragment::FT_Data); - WriteBytes(cast(F).getContents().str()); + WriteBytes(cast(F).getContents()); } } else { Asm.writeSectionData(&SD, Layout); @@ -1220,23 +1556,20 @@ void ELFObjectWriter::WriteObject(MCAssembler &Asm, } // Write out the ELF header ... - WriteHeader(SectionHeaderOffset, NumSections + 1); + WriteHeader(Asm, SectionHeaderOffset, NumSections + 1); // ... then the regular sections ... // + because of .shstrtab for (unsigned i = 0; i < NumRegularSections + 1; ++i) WriteDataSectionData(Asm, Layout, *Sections[i]); - FileOff = OS.tell(); - uint64_t Padding = OffsetToAlignment(FileOff, NaturalAlignment); + uint64_t Padding = OffsetToAlignment(OS.tell(), NaturalAlignment); WriteZeros(Padding); // ... then the section header table ... WriteSectionHeader(Asm, GroupMap, Layout, SectionIndexMap, SectionOffsetMap); - FileOff = OS.tell(); - // ... and then the remaining sections ... for (unsigned i = NumRegularSections + 1; i < NumSections; ++i) WriteDataSectionData(Asm, Layout, *Sections[i]); @@ -1257,468 +1590,5 @@ ELFObjectWriter::IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, MCObjectWriter *llvm::createELFObjectWriter(MCELFObjectTargetWriter *MOTW, raw_ostream &OS, bool IsLittleEndian) { - switch (MOTW->getEMachine()) { - case ELF::EM_386: - case ELF::EM_X86_64: - return new ELFObjectWriter(MOTW, OS, IsLittleEndian); break; - case ELF::EM_ARM: - return new ARMELFObjectWriter(MOTW, OS, IsLittleEndian); break; - case ELF::EM_MBLAZE: - return new MBlazeELFObjectWriter(MOTW, OS, IsLittleEndian); break; - case ELF::EM_PPC: - case ELF::EM_PPC64: - return new PPCELFObjectWriter(MOTW, OS, IsLittleEndian); break; - case ELF::EM_MIPS: - return new MipsELFObjectWriter(MOTW, OS, IsLittleEndian); break; - default: llvm_unreachable("Unsupported architecture"); break; - } -} - -unsigned ELFObjectWriter::GetRelocType(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel, - bool IsRelocWithSymbol, - int64_t Addend) const { - return TargetObjectWriter->GetRelocType(Target, Fixup, IsPCRel, - IsRelocWithSymbol, Addend); -} - -/// START OF SUBCLASSES for ELFObjectWriter -//===- ARMELFObjectWriter -------------------------------------------===// - -ARMELFObjectWriter::ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW, - raw_ostream &_OS, - bool IsLittleEndian) - : ELFObjectWriter(MOTW, _OS, IsLittleEndian) -{} - -ARMELFObjectWriter::~ARMELFObjectWriter() -{} - -// FIXME: get the real EABI Version from the Triple. -unsigned ARMELFObjectWriter::getEFlags() { - return ELF::EF_ARM_EABIMASK & DefaultEABIVersion; -} - -// In ARM, _MergedGlobals and other most symbols get emitted directly. -// I.e. not as an offset to a section symbol. -// This code is an approximation of what ARM/gcc does. - -STATISTIC(PCRelCount, "Total number of PIC Relocations"); -STATISTIC(NonPCRelCount, "Total number of non-PIC relocations"); - -const MCSymbol *ARMELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm, - const MCValue &Target, - const MCFragment &F, - const MCFixup &Fixup, - bool IsPCRel) const { - const MCSymbol &Symbol = Target.getSymA()->getSymbol(); - bool EmitThisSym = false; - - const MCSectionELF &Section = - static_cast(Symbol.getSection()); - bool InNormalSection = true; - unsigned RelocType = 0; - RelocType = GetRelocTypeInner(Target, Fixup, IsPCRel); - - DEBUG( - const MCSymbolRefExpr::VariantKind Kind = Target.getSymA()->getKind(); - MCSymbolRefExpr::VariantKind Kind2; - Kind2 = Target.getSymB() ? Target.getSymB()->getKind() : - MCSymbolRefExpr::VK_None; - dbgs() << "considering symbol " - << Section.getSectionName() << "/" - << Symbol.getName() << "/" - << " Rel:" << (unsigned)RelocType - << " Kind: " << (int)Kind << "/" << (int)Kind2 - << " Tmp:" - << Symbol.isAbsolute() << "/" << Symbol.isDefined() << "/" - << Symbol.isVariable() << "/" << Symbol.isTemporary() - << " Counts:" << PCRelCount << "/" << NonPCRelCount << "\n"); - - if (IsPCRel) { ++PCRelCount; - switch (RelocType) { - default: - // Most relocation types are emitted as explicit symbols - InNormalSection = - StringSwitch(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".data.rel", false) - .Case(".bss", false) - .Default(true); - EmitThisSym = true; - break; - case ELF::R_ARM_ABS32: - // But things get strange with R_ARM_ABS32 - // In this case, most things that go in .rodata show up - // as section relative relocations - InNormalSection = - StringSwitch(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".data.rel", false) - .Case(".rodata", false) - .Case(".bss", false) - .Default(true); - EmitThisSym = false; - break; - } - } else { - NonPCRelCount++; - InNormalSection = - StringSwitch(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".rodata", false) - .Case(".data.rel", false) - .Case(".bss", false) - .Default(true); - - switch (RelocType) { - default: EmitThisSym = true; break; - case ELF::R_ARM_ABS32: EmitThisSym = false; break; - } - } - - if (EmitThisSym) - return &Symbol; - if (! Symbol.isTemporary() && InNormalSection) { - return &Symbol; - } - return NULL; -} - -// Need to examine the Fixup when determining whether to -// emit the relocation as an explicit symbol or as a section relative -// offset -unsigned ARMELFObjectWriter::GetRelocType(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel, - bool IsRelocWithSymbol, - int64_t Addend) const { - return GetRelocTypeInner(Target, Fixup, IsPCRel); -} - -unsigned ARMELFObjectWriter::GetRelocTypeInner(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel) const { - MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ? - MCSymbolRefExpr::VK_None : Target.getSymA()->getKind(); - - unsigned Type = 0; - if (IsPCRel) { - switch ((unsigned)Fixup.getKind()) { - default: assert(0 && "Unimplemented"); - case FK_Data_4: - switch (Modifier) { - default: llvm_unreachable("Unsupported Modifier"); - case MCSymbolRefExpr::VK_None: - Type = ELF::R_ARM_REL32; - break; - case MCSymbolRefExpr::VK_ARM_TLSGD: - assert(0 && "unimplemented"); - break; - case MCSymbolRefExpr::VK_ARM_GOTTPOFF: - Type = ELF::R_ARM_TLS_IE32; - break; - } - break; - case ARM::fixup_arm_uncondbranch: - switch (Modifier) { - case MCSymbolRefExpr::VK_ARM_PLT: - Type = ELF::R_ARM_PLT32; - break; - default: - Type = ELF::R_ARM_CALL; - break; - } - break; - case ARM::fixup_arm_condbranch: - Type = ELF::R_ARM_JUMP24; - break; - case ARM::fixup_arm_movt_hi16: - case ARM::fixup_arm_movt_hi16_pcrel: - Type = ELF::R_ARM_MOVT_PREL; - break; - case ARM::fixup_arm_movw_lo16: - case ARM::fixup_arm_movw_lo16_pcrel: - Type = ELF::R_ARM_MOVW_PREL_NC; - break; - case ARM::fixup_t2_movt_hi16: - case ARM::fixup_t2_movt_hi16_pcrel: - Type = ELF::R_ARM_THM_MOVT_PREL; - break; - case ARM::fixup_t2_movw_lo16: - case ARM::fixup_t2_movw_lo16_pcrel: - Type = ELF::R_ARM_THM_MOVW_PREL_NC; - break; - case ARM::fixup_arm_thumb_bl: - case ARM::fixup_arm_thumb_blx: - switch (Modifier) { - case MCSymbolRefExpr::VK_ARM_PLT: - Type = ELF::R_ARM_THM_CALL; - break; - default: - Type = ELF::R_ARM_NONE; - break; - } - break; - } - } else { - switch ((unsigned)Fixup.getKind()) { - default: llvm_unreachable("invalid fixup kind!"); - case FK_Data_4: - switch (Modifier) { - default: llvm_unreachable("Unsupported Modifier"); break; - case MCSymbolRefExpr::VK_ARM_GOT: - Type = ELF::R_ARM_GOT_BREL; - break; - case MCSymbolRefExpr::VK_ARM_TLSGD: - Type = ELF::R_ARM_TLS_GD32; - break; - case MCSymbolRefExpr::VK_ARM_TPOFF: - Type = ELF::R_ARM_TLS_LE32; - break; - case MCSymbolRefExpr::VK_ARM_GOTTPOFF: - Type = ELF::R_ARM_TLS_IE32; - break; - case MCSymbolRefExpr::VK_None: - Type = ELF::R_ARM_ABS32; - break; - case MCSymbolRefExpr::VK_ARM_GOTOFF: - Type = ELF::R_ARM_GOTOFF32; - break; - } - break; - case ARM::fixup_arm_ldst_pcrel_12: - case ARM::fixup_arm_pcrel_10: - case ARM::fixup_arm_adr_pcrel_12: - case ARM::fixup_arm_thumb_bl: - case ARM::fixup_arm_thumb_cb: - case ARM::fixup_arm_thumb_cp: - case ARM::fixup_arm_thumb_br: - assert(0 && "Unimplemented"); - break; - case ARM::fixup_arm_uncondbranch: - Type = ELF::R_ARM_CALL; - break; - case ARM::fixup_arm_condbranch: - Type = ELF::R_ARM_JUMP24; - break; - case ARM::fixup_arm_movt_hi16: - Type = ELF::R_ARM_MOVT_ABS; - break; - case ARM::fixup_arm_movw_lo16: - Type = ELF::R_ARM_MOVW_ABS_NC; - break; - case ARM::fixup_t2_movt_hi16: - Type = ELF::R_ARM_THM_MOVT_ABS; - break; - case ARM::fixup_t2_movw_lo16: - Type = ELF::R_ARM_THM_MOVW_ABS_NC; - break; - } - } - - return Type; -} - -//===- PPCELFObjectWriter -------------------------------------------===// - -PPCELFObjectWriter::PPCELFObjectWriter(MCELFObjectTargetWriter *MOTW, - raw_ostream &_OS, - bool IsLittleEndian) - : ELFObjectWriter(MOTW, _OS, IsLittleEndian) { -} - -PPCELFObjectWriter::~PPCELFObjectWriter() { -} - -unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel, - bool IsRelocWithSymbol, - int64_t Addend) const { - // determine the type of the relocation - unsigned Type; - if (IsPCRel) { - switch ((unsigned)Fixup.getKind()) { - default: - llvm_unreachable("Unimplemented"); - case PPC::fixup_ppc_br24: - Type = ELF::R_PPC_REL24; - break; - case FK_PCRel_4: - Type = ELF::R_PPC_REL32; - break; - } - } else { - switch ((unsigned)Fixup.getKind()) { - default: llvm_unreachable("invalid fixup kind!"); - case PPC::fixup_ppc_br24: - Type = ELF::R_PPC_ADDR24; - break; - case PPC::fixup_ppc_brcond14: - Type = ELF::R_PPC_ADDR14_BRTAKEN; // XXX: or BRNTAKEN?_ - break; - case PPC::fixup_ppc_ha16: - Type = ELF::R_PPC_ADDR16_HA; - break; - case PPC::fixup_ppc_lo16: - Type = ELF::R_PPC_ADDR16_LO; - break; - case PPC::fixup_ppc_lo14: - Type = ELF::R_PPC_ADDR14; - break; - case FK_Data_4: - Type = ELF::R_PPC_ADDR32; - break; - case FK_Data_2: - Type = ELF::R_PPC_ADDR16; - break; - } - } - return Type; -} - -void PPCELFObjectWriter:: -adjustFixupOffset(const MCFixup &Fixup, uint64_t &RelocOffset) { - switch ((unsigned)Fixup.getKind()) { - case PPC::fixup_ppc_ha16: - case PPC::fixup_ppc_lo16: - RelocOffset += 2; - break; - default: - break; - } -} - -//===- MBlazeELFObjectWriter -------------------------------------------===// - -MBlazeELFObjectWriter::MBlazeELFObjectWriter(MCELFObjectTargetWriter *MOTW, - raw_ostream &_OS, - bool IsLittleEndian) - : ELFObjectWriter(MOTW, _OS, IsLittleEndian) { -} - -MBlazeELFObjectWriter::~MBlazeELFObjectWriter() { -} - -unsigned MBlazeELFObjectWriter::GetRelocType(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel, - bool IsRelocWithSymbol, - int64_t Addend) const { - // determine the type of the relocation - unsigned Type; - if (IsPCRel) { - switch ((unsigned)Fixup.getKind()) { - default: - llvm_unreachable("Unimplemented"); - case FK_PCRel_4: - Type = ELF::R_MICROBLAZE_64_PCREL; - break; - case FK_PCRel_2: - Type = ELF::R_MICROBLAZE_32_PCREL; - break; - } - } else { - switch ((unsigned)Fixup.getKind()) { - default: llvm_unreachable("invalid fixup kind!"); - case FK_Data_4: - Type = ((IsRelocWithSymbol || Addend !=0) - ? ELF::R_MICROBLAZE_32 - : ELF::R_MICROBLAZE_64); - break; - case FK_Data_2: - Type = ELF::R_MICROBLAZE_32; - break; - } - } - return Type; -} - -//===- MipsELFObjectWriter -------------------------------------------===// - -MipsELFObjectWriter::MipsELFObjectWriter(MCELFObjectTargetWriter *MOTW, - raw_ostream &_OS, - bool IsLittleEndian) - : ELFObjectWriter(MOTW, _OS, IsLittleEndian) {} - -MipsELFObjectWriter::~MipsELFObjectWriter() {} - -// FIXME: get the real EABI Version from the Triple. -unsigned MipsELFObjectWriter::getEFlags() { - return ELF::EF_MIPS_NOREORDER | ELF::EF_MIPS_ARCH_32R2; -} - -const MCSymbol *MipsELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm, - const MCValue &Target, - const MCFragment &F, - const MCFixup &Fixup, - bool IsPCRel) const { - assert(Target.getSymA() && "SymA cannot be 0."); - const MCSymbol &Sym = Target.getSymA()->getSymbol(); - - if (Sym.getSection().getKind().isMergeableCString() || - Sym.getSection().getKind().isMergeableConst()) - return &Sym; - - return NULL; -} - -unsigned MipsELFObjectWriter::GetRelocType(const MCValue &Target, - const MCFixup &Fixup, - bool IsPCRel, - bool IsRelocWithSymbol, - int64_t Addend) const { - // determine the type of the relocation - unsigned Type = (unsigned)ELF::R_MIPS_NONE; - unsigned Kind = (unsigned)Fixup.getKind(); - - switch (Kind) { - default: - llvm_unreachable("invalid fixup kind!"); - case FK_Data_4: - Type = ELF::R_MIPS_32; - break; - case FK_GPRel_4: - Type = ELF::R_MIPS_GPREL32; - break; - case Mips::fixup_Mips_GPREL16: - Type = ELF::R_MIPS_GPREL16; - break; - case Mips::fixup_Mips_26: - Type = ELF::R_MIPS_26; - break; - case Mips::fixup_Mips_CALL16: - Type = ELF::R_MIPS_CALL16; - break; - case Mips::fixup_Mips_GOT_Global: - case Mips::fixup_Mips_GOT_Local: - Type = ELF::R_MIPS_GOT16; - break; - case Mips::fixup_Mips_HI16: - Type = ELF::R_MIPS_HI16; - break; - case Mips::fixup_Mips_LO16: - Type = ELF::R_MIPS_LO16; - break; - case Mips::fixup_Mips_TLSGD: - Type = ELF::R_MIPS_TLS_GD; - break; - case Mips::fixup_Mips_GOTTPREL: - Type = ELF::R_MIPS_TLS_GOTTPREL; - break; - case Mips::fixup_Mips_TPREL_HI: - Type = ELF::R_MIPS_TLS_TPREL_HI16; - break; - case Mips::fixup_Mips_TPREL_LO: - Type = ELF::R_MIPS_TLS_TPREL_LO16; - break; - case Mips::fixup_Mips_Branch_PCRel: - case Mips::fixup_Mips_PC16: - Type = ELF::R_MIPS_PC16; - break; - } - - return Type; + return new ELFObjectWriter(MOTW, OS, IsLittleEndian); }