#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCValue.h"
-#include "llvm/Object/StringTableBuilder.h"
+#include "llvm/MC/StringTableBuilder.h"
#include "llvm/Support/Compression.h"
#include "llvm/Support/Debug.h"
-#include "llvm/Support/Endian.h"
#include "llvm/Support/ELF.h"
+#include "llvm/Support/Endian.h"
#include "llvm/Support/ErrorHandling.h"
#include <vector>
using namespace llvm;
struct ELFRelocationEntry {
uint64_t Offset; // Where is the relocation.
- bool UseSymbol; // Relocate with a symbol, not the section.
- union {
- const MCSymbol *Symbol; // The symbol to relocate with.
- const MCSectionData *Section; // The section to relocate with.
- };
+ const MCSymbol *Symbol; // The symbol to relocate with.
unsigned Type; // The type of the relocation.
uint64_t Addend; // The addend to use.
ELFRelocationEntry(uint64_t Offset, const MCSymbol *Symbol, unsigned Type,
uint64_t Addend)
- : Offset(Offset), UseSymbol(true), Symbol(Symbol), Type(Type),
- Addend(Addend) {}
-
- ELFRelocationEntry(uint64_t Offset, const MCSectionData *Section,
- unsigned Type, uint64_t Addend)
- : Offset(Offset), UseSymbol(false), Section(Section), Type(Type),
- Addend(Addend) {}
+ : Offset(Offset), Symbol(Symbol), Type(Type), Addend(Addend) {}
};
class ELFObjectWriter : public MCObjectWriter {
// Support lexicographic sorting.
bool operator<(const ELFSymbolData &RHS) const {
+ unsigned LHSType = MCELF::GetType(*SymbolData);
+ unsigned RHSType = MCELF::GetType(*RHS.SymbolData);
+ if (LHSType == ELF::STT_SECTION && RHSType != ELF::STT_SECTION)
+ return false;
+ if (LHSType != ELF::STT_SECTION && RHSType == ELF::STT_SECTION)
+ return true;
+ if (LHSType == ELF::STT_SECTION && RHSType == ELF::STT_SECTION)
+ return SectionIndex < RHS.SectionIndex;
return Name < RHS.Name;
}
};
}
public:
- ELFObjectWriter(MCELFObjectTargetWriter *MOTW, raw_ostream &_OS,
+ ELFObjectWriter(MCELFObjectTargetWriter *MOTW, raw_ostream &OS,
bool IsLittleEndian)
- : MCObjectWriter(_OS, IsLittleEndian), FWriter(IsLittleEndian),
+ : MCObjectWriter(OS, IsLittleEndian), FWriter(IsLittleEndian),
TargetObjectWriter(MOTW), NeedsGOT(false) {}
+ void reset() override {
+ UsedInReloc.clear();
+ WeakrefUsedInReloc.clear();
+ Renames.clear();
+ Relocations.clear();
+ ShStrTabBuilder.clear();
+ StrTabBuilder.clear();
+ FileSymbolData.clear();
+ LocalSymbolData.clear();
+ ExternalSymbolData.clear();
+ UndefinedSymbolData.clear();
+ MCObjectWriter::reset();
+ }
+
virtual ~ELFObjectWriter();
void WriteWord(uint64_t W) {
const MCSymbolData *SD, uint64_t C,
unsigned Type) const;
- void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
+ void RecordRelocation(MCAssembler &Asm, const MCAsmLayout &Layout,
const MCFragment *Fragment, const MCFixup &Fixup,
MCValue Target, bool &IsPCRel,
uint64_t &FixedValue) override;
/// \param NumRegularSections - Number of non-relocation sections.
void computeSymbolTable(MCAssembler &Asm, const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap,
- RevGroupMapTy RevGroupMap,
+ const RevGroupMapTy &RevGroupMap,
unsigned NumRegularSections);
- void ComputeIndexMap(MCAssembler &Asm,
+ void computeIndexMap(MCAssembler &Asm,
SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap);
+ RelMapTy &RelMap);
- void CreateRelocationSections(MCAssembler &Asm, MCAsmLayout &Layout,
- RelMapTy &RelMap);
+ MCSectionData *createRelocationSection(MCAssembler &Asm,
+ const MCSectionData &SD);
void CompressDebugSections(MCAssembler &Asm, MCAsmLayout &Layout);
const RelMapTy &RelMap);
void CreateMetadataSections(MCAssembler &Asm, MCAsmLayout &Layout,
- SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap);
+ SectionIndexMapTy &SectionIndexMap);
// 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,
+ void createIndexedSections(MCAssembler &Asm, MCAsmLayout &Layout,
GroupMapTy &GroupMap,
RevGroupMapTy &RevGroupMap,
SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap);
+ RelMapTy &RelMap);
void ExecutePostLayoutBinding(MCAssembler &Asm,
const MCAsmLayout &Layout) override;
- void WriteSectionHeader(MCAssembler &Asm, const GroupMapTy &GroupMap,
+ void writeSectionHeader(MCAssembler &Asm, const GroupMapTy &GroupMap,
const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap,
+ const RelMapTy &RelMap,
const SectionOffsetMapTy &SectionOffsetMap);
void ComputeSectionOrder(MCAssembler &Asm,
bool InSet,
bool IsPCRel) const override;
+ bool isWeak(const MCSymbolData &SD) const override;
+
void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
- void WriteSection(MCAssembler &Asm,
+ void writeSection(MCAssembler &Asm,
const SectionIndexMapTy &SectionIndexMap,
+ const RelMapTy &RelMap,
uint32_t GroupSymbolIndex,
uint64_t Offset, uint64_t Size, uint64_t Alignment,
const MCSectionELF &Section);
MCContext &Ctx = Asm.getContext();
const MCSectionELF *SymtabShndxSection =
- Ctx.getELFSection(".symtab_shndxr", ELF::SHT_SYMTAB_SHNDX, 0,
- SectionKind::getReadOnly(), 4, "");
+ Ctx.getELFSection(".symtab_shndxr", ELF::SHT_SYMTAB_SHNDX, 0, 4, "");
MCSectionData *SymtabShndxSD =
&Asm.getOrCreateSectionData(*SymtabShndxSection);
SymtabShndxSD->setAlignment(4);
WriteSymbol(Writer, MSD, Layout);
}
- // Write out a symbol table entry for each regular section.
- for (MCAssembler::const_iterator i = Asm.begin(), e = Asm.end(); i != e;
- ++i) {
- const MCSectionELF &Section =
- static_cast<const MCSectionELF&>(i->getSection());
- if (Section.getType() == ELF::SHT_RELA ||
- Section.getType() == ELF::SHT_REL ||
- Section.getType() == ELF::SHT_STRTAB ||
- Section.getType() == ELF::SHT_SYMTAB ||
- Section.getType() == ELF::SHT_SYMTAB_SHNDX)
- continue;
- Writer.writeSymbol(0, ELF::STT_SECTION, 0, 0, ELF::STV_DEFAULT,
- SectionIndexMap.lookup(&Section), false);
- LastLocalSymbolIndex++;
- }
-
for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) {
ELFSymbolData &MSD = ExternalSymbolData[i];
MCSymbolData &Data = *MSD.SymbolData;
}
// Most TLS relocations use a got, so they need the symbol. Even those that
- // are just an offset (@tpoff), require a symbol in some linkers (gold,
- // but not bfd ld).
+ // are just an offset (@tpoff), require a symbol in gold versions before
+ // 5efeedf61e4fe720fd3e9a08e6c91c10abb66d42 (2014-09-26) which fixed
+ // http://sourceware.org/PR16773.
if (Flags & ELF::SHF_TLS)
return true;
if (Asm.isThumbFunc(&Sym))
return true;
- if (TargetObjectWriter->needsRelocateWithSymbol(Type))
+ if (TargetObjectWriter->needsRelocateWithSymbol(*SD, Type))
return true;
return false;
}
return nullptr;
}
-void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm,
+static bool isWeak(const MCSymbolData &D) {
+ return D.getFlags() & ELF_STB_Weak || MCELF::GetType(D) == ELF::STT_GNU_IFUNC;
+}
+
+void ELFObjectWriter::RecordRelocation(MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
- const MCFixup &Fixup,
- MCValue Target,
- bool &IsPCRel,
- uint64_t &FixedValue) {
+ const MCFixup &Fixup, MCValue Target,
+ bool &IsPCRel, uint64_t &FixedValue) {
const MCSectionData *FixupSection = Fragment->getParent();
uint64_t C = Target.getConstant();
uint64_t FixupOffset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
Fixup.getLoc(), "Cannot represent a difference across sections");
const MCSymbolData &SymBD = Asm.getSymbolData(SymB);
+ if (::isWeak(SymBD))
+ Asm.getContext().FatalError(
+ Fixup.getLoc(), "Cannot represent a subtraction with a weak symbol");
+
uint64_t SymBOffset = Layout.getSymbolOffset(&SymBD);
uint64_t K = SymBOffset - FixupOffset;
IsPCRel = true;
if (!RelocateWithSymbol) {
const MCSection *SecA =
(SymA && !SymA->isUndefined()) ? &SymA->getSection() : nullptr;
- const MCSectionData *SecAD = SecA ? &Asm.getSectionData(*SecA) : nullptr;
- ELFRelocationEntry Rec(FixupOffset, SecAD, Type, Addend);
+ auto *ELFSec = cast_or_null<MCSectionELF>(SecA);
+ MCSymbol *SectionSymbol =
+ ELFSec ? Asm.getContext().getOrCreateSectionSymbol(*ELFSec)
+ : nullptr;
+ ELFRelocationEntry Rec(FixupOffset, SectionSymbol, Type, Addend);
Relocations[FixupSection].push_back(Rec);
return;
}
return true;
}
-void ELFObjectWriter::ComputeIndexMap(MCAssembler &Asm,
+void ELFObjectWriter::computeIndexMap(MCAssembler &Asm,
SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap) {
+ RelMapTy &RelMap) {
unsigned Index = 1;
for (MCAssembler::iterator it = Asm.begin(),
ie = Asm.end(); it != ie; ++it) {
for (MCAssembler::iterator it = Asm.begin(),
ie = Asm.end(); it != ie; ++it) {
+ const MCSectionData &SD = *it;
const MCSectionELF &Section =
- static_cast<const MCSectionELF &>(it->getSection());
+ static_cast<const MCSectionELF &>(SD.getSection());
if (Section.getType() == ELF::SHT_GROUP ||
Section.getType() == ELF::SHT_REL ||
Section.getType() == ELF::SHT_RELA)
continue;
SectionIndexMap[&Section] = Index++;
- const MCSectionELF *RelSection = RelMap.lookup(&Section);
- if (RelSection)
+ if (MCSectionData *RelSD = createRelocationSection(Asm, SD)) {
+ const MCSectionELF *RelSection =
+ static_cast<const MCSectionELF *>(&RelSD->getSection());
+ RelMap[RelSection] = &Section;
SectionIndexMap[RelSection] = Index++;
+ }
}
}
void
ELFObjectWriter::computeSymbolTable(MCAssembler &Asm, const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap,
- RevGroupMapTy RevGroupMap,
+ const RevGroupMapTy &RevGroupMap,
unsigned NumRegularSections) {
// FIXME: Is this the correct place to do this?
// FIXME: Why is an undefined reference to _GLOBAL_OFFSET_TABLE_ needed?
MSD.SectionIndex = ELF::SHN_COMMON;
} else if (BaseSymbol->isUndefined()) {
if (isSignature && !Used)
- MSD.SectionIndex = SectionIndexMap.lookup(RevGroupMap[&Symbol]);
+ MSD.SectionIndex = SectionIndexMap.lookup(RevGroupMap.lookup(&Symbol));
else
MSD.SectionIndex = ELF::SHN_UNDEF;
if (!Used && WeakrefUsed)
assert(MSD.SectionIndex && "Invalid section index!");
}
- // The @@@ in symbol version is replaced with @ in undefined symbols and
- // @@ in defined ones.
+ // The @@@ in symbol version is replaced with @ in undefined symbols and @@
+ // in defined ones.
+ //
+ // FIXME: All name handling should be done before we get to the writer,
+ // including dealing with GNU-style version suffixes. Fixing this isn't
+ // trivial.
+ //
+ // We thus have to be careful to not perform the symbol version replacement
+ // blindly:
+ //
+ // The ELF format is used on Windows by the MCJIT engine. Thus, on
+ // Windows, the ELFObjectWriter can encounter symbols mangled using the MS
+ // Visual Studio C++ name mangling scheme. Symbols mangled using the MSVC
+ // C++ name mangling can legally have "@@@" as a sub-string. In that case,
+ // the EFLObjectWriter should not interpret the "@@@" sub-string as
+ // specifying GNU-style symbol versioning. The ELFObjectWriter therefore
+ // checks for the MSVC C++ name mangling prefix which is either "?", "@?",
+ // "__imp_?" or "__imp_@?".
+ //
+ // It would have been interesting to perform the MS mangling prefix check
+ // only when the target triple is of the form *-pc-windows-elf. But, it
+ // seems that this information is not easily accessible from the
+ // ELFObjectWriter.
StringRef Name = Symbol.getName();
- SmallString<32> Buf;
- size_t Pos = Name.find("@@@");
- if (Pos != StringRef::npos) {
- Buf += Name.substr(0, Pos);
- unsigned Skip = MSD.SectionIndex == ELF::SHN_UNDEF ? 2 : 1;
- Buf += Name.substr(Pos + Skip);
- Name = Buf;
+ if (!Name.startswith("?") && !Name.startswith("@?") &&
+ !Name.startswith("__imp_?") && !Name.startswith("__imp_@?")) {
+ // This symbol isn't following the MSVC C++ name mangling convention. We
+ // can thus safely interpret the @@@ in symbol names as specifying symbol
+ // versioning.
+ SmallString<32> Buf;
+ size_t Pos = Name.find("@@@");
+ if (Pos != StringRef::npos) {
+ Buf += Name.substr(0, Pos);
+ unsigned Skip = MSD.SectionIndex == ELF::SHN_UNDEF ? 2 : 1;
+ Buf += Name.substr(Pos + Skip);
+ Name = Buf;
+ }
}
- MSD.Name = StrTabBuilder.add(Name);
+
+ // Sections have their own string table
+ if (MCELF::GetType(SD) != ELF::STT_SECTION)
+ MSD.Name = StrTabBuilder.add(Name);
if (MSD.SectionIndex == ELF::SHN_UNDEF)
UndefinedSymbolData.push_back(MSD);
for (auto i = Asm.file_names_begin(), e = Asm.file_names_end(); i != e; ++i)
StrTabBuilder.add(*i);
- StrTabBuilder.finalize();
+ StrTabBuilder.finalize(StringTableBuilder::ELF);
for (auto i = Asm.file_names_begin(), e = Asm.file_names_end(); i != e; ++i)
FileSymbolData.push_back(StrTabBuilder.getOffset(*i));
- for (ELFSymbolData& MSD : LocalSymbolData)
- MSD.StringIndex = StrTabBuilder.getOffset(MSD.Name);
- for (ELFSymbolData& MSD : ExternalSymbolData)
+ for (ELFSymbolData &MSD : LocalSymbolData)
+ MSD.StringIndex = MCELF::GetType(*MSD.SymbolData) == ELF::STT_SECTION
+ ? 0
+ : StrTabBuilder.getOffset(MSD.Name);
+ for (ELFSymbolData &MSD : ExternalSymbolData)
MSD.StringIndex = StrTabBuilder.getOffset(MSD.Name);
for (ELFSymbolData& MSD : UndefinedSymbolData)
MSD.StringIndex = StrTabBuilder.getOffset(MSD.Name);
for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i)
LocalSymbolData[i].SymbolData->setIndex(Index++);
- Index += NumRegularSections;
-
for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i)
ExternalSymbolData[i].SymbolData->setIndex(Index++);
for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i)
UndefinedSymbolData[i].SymbolData->setIndex(Index++);
}
-void ELFObjectWriter::CreateRelocationSections(MCAssembler &Asm,
- MCAsmLayout &Layout,
- RelMapTy &RelMap) {
- for (MCAssembler::const_iterator it = Asm.begin(),
- ie = Asm.end(); it != ie; ++it) {
- const MCSectionData &SD = *it;
- if (Relocations[&SD].empty())
- continue;
-
- MCContext &Ctx = Asm.getContext();
- const MCSectionELF &Section =
- static_cast<const MCSectionELF&>(SD.getSection());
+MCSectionData *
+ELFObjectWriter::createRelocationSection(MCAssembler &Asm,
+ const MCSectionData &SD) {
+ if (Relocations[&SD].empty())
+ return nullptr;
- const StringRef SectionName = Section.getSectionName();
- std::string RelaSectionName = hasRelocationAddend() ? ".rela" : ".rel";
- RelaSectionName += SectionName;
+ MCContext &Ctx = Asm.getContext();
+ const MCSectionELF &Section =
+ static_cast<const MCSectionELF &>(SD.getSection());
- unsigned EntrySize;
- if (hasRelocationAddend())
- EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rela) : sizeof(ELF::Elf32_Rela);
- else
- EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rel) : sizeof(ELF::Elf32_Rel);
+ const StringRef SectionName = Section.getSectionName();
+ std::string RelaSectionName = hasRelocationAddend() ? ".rela" : ".rel";
+ RelaSectionName += SectionName;
- unsigned Flags = 0;
- StringRef Group = "";
- if (Section.getFlags() & ELF::SHF_GROUP) {
- Flags = ELF::SHF_GROUP;
- Group = Section.getGroup()->getName();
- }
+ unsigned EntrySize;
+ if (hasRelocationAddend())
+ EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rela) : sizeof(ELF::Elf32_Rela);
+ else
+ EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rel) : sizeof(ELF::Elf32_Rel);
- const MCSectionELF *RelaSection =
- Ctx.getELFSection(RelaSectionName, hasRelocationAddend() ?
- ELF::SHT_RELA : ELF::SHT_REL, Flags,
- SectionKind::getReadOnly(),
- EntrySize, Group);
- RelMap[&Section] = RelaSection;
- Asm.getOrCreateSectionData(*RelaSection);
+ unsigned Flags = 0;
+ StringRef Group = "";
+ if (Section.getFlags() & ELF::SHF_GROUP) {
+ Flags = ELF::SHF_GROUP;
+ Group = Section.getGroup()->getName();
}
+
+ const MCSectionELF *RelaSection = Ctx.getELFSection(
+ RelaSectionName, hasRelocationAddend() ? ELF::SHT_RELA : ELF::SHT_REL,
+ Flags, EntrySize, Group, true);
+ return &Asm.getOrCreateSectionData(*RelaSection);
}
static SmallVector<char, 128>
static bool
prependCompressionHeader(uint64_t Size,
SmallVectorImpl<char> &CompressedContents) {
- static const StringRef Magic = "ZLIB";
+ const StringRef Magic = "ZLIB";
if (Size <= Magic.size() + sizeof(Size) + CompressedContents.size())
return false;
if (sys::IsLittleEndianHost)
- Size = sys::SwapByteOrder(Size);
+ sys::swapByteOrder(Size);
CompressedContents.insert(CompressedContents.begin(),
Magic.size() + sizeof(Size), 0);
std::copy(Magic.begin(), Magic.end(), CompressedContents.begin());
void ELFObjectWriter::WriteRelocations(MCAssembler &Asm, MCAsmLayout &Layout,
const RelMapTy &RelMap) {
- for (MCAssembler::const_iterator it = Asm.begin(),
- ie = Asm.end(); it != ie; ++it) {
- const MCSectionData &SD = *it;
- const MCSectionELF &Section =
- static_cast<const MCSectionELF&>(SD.getSection());
+ for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) {
+ MCSectionData &RelSD = *it;
+ const MCSectionELF &RelSection =
+ static_cast<const MCSectionELF &>(RelSD.getSection());
- const MCSectionELF *RelaSection = RelMap.lookup(&Section);
- if (!RelaSection)
+ unsigned Type = RelSection.getType();
+ if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA)
continue;
- MCSectionData &RelaSD = Asm.getOrCreateSectionData(*RelaSection);
- RelaSD.setAlignment(is64Bit() ? 8 : 4);
- MCDataFragment *F = new MCDataFragment(&RelaSD);
- WriteRelocationsFragment(Asm, F, &*it);
+ const MCSectionELF *Section = RelMap.lookup(&RelSection);
+ MCSectionData &SD = Asm.getOrCreateSectionData(*Section);
+ RelSD.setAlignment(is64Bit() ? 8 : 4);
+
+ MCDataFragment *F = new MCDataFragment(&RelSD);
+ WriteRelocationsFragment(Asm, F, &SD);
}
}
return B.Offset - A.Offset;
if (B.Type != A.Type)
return A.Type - B.Type;
- llvm_unreachable("ELFRelocs might be unstable!");
+ //llvm_unreachable("ELFRelocs might be unstable!");
+ return 0;
}
static void sortRelocs(const MCAssembler &Asm,
for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
const ELFRelocationEntry &Entry = Relocs[e - i - 1];
-
- unsigned Index;
- if (Entry.UseSymbol) {
- Index = getSymbolIndexInSymbolTable(Asm, Entry.Symbol);
- } else {
- const MCSectionData *Sec = Entry.Section;
- if (Sec)
- Index = Sec->getOrdinal() + FileSymbolData.size() +
- LocalSymbolData.size() + 1;
- else
- Index = 0;
- }
+ unsigned Index =
+ Entry.Symbol ? getSymbolIndexInSymbolTable(Asm, Entry.Symbol) : 0;
if (is64Bit()) {
write(*F, Entry.Offset);
}
}
-void ELFObjectWriter::CreateMetadataSections(MCAssembler &Asm,
- MCAsmLayout &Layout,
- SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap) {
+void ELFObjectWriter::CreateMetadataSections(
+ MCAssembler &Asm, MCAsmLayout &Layout, SectionIndexMapTy &SectionIndexMap) {
MCContext &Ctx = Asm.getContext();
MCDataFragment *F;
// We construct .shstrtab, .symtab and .strtab in this order to match gnu as.
const MCSectionELF *ShstrtabSection =
- Ctx.getELFSection(".shstrtab", ELF::SHT_STRTAB, 0,
- SectionKind::getReadOnly());
+ Ctx.getELFSection(".shstrtab", ELF::SHT_STRTAB, 0);
MCSectionData &ShstrtabSD = Asm.getOrCreateSectionData(*ShstrtabSection);
ShstrtabSD.setAlignment(1);
+ ShstrtabIndex = SectionIndexMap.size() + 1;
+ SectionIndexMap[ShstrtabSection] = ShstrtabIndex;
const MCSectionELF *SymtabSection =
Ctx.getELFSection(".symtab", ELF::SHT_SYMTAB, 0,
- SectionKind::getReadOnly(),
EntrySize, "");
MCSectionData &SymtabSD = Asm.getOrCreateSectionData(*SymtabSection);
SymtabSD.setAlignment(is64Bit() ? 8 : 4);
+ SymbolTableIndex = SectionIndexMap.size() + 1;
+ SectionIndexMap[SymtabSection] = SymbolTableIndex;
const MCSectionELF *StrtabSection;
- StrtabSection = Ctx.getELFSection(".strtab", ELF::SHT_STRTAB, 0,
- SectionKind::getReadOnly());
+ StrtabSection = Ctx.getELFSection(".strtab", ELF::SHT_STRTAB, 0);
MCSectionData &StrtabSD = Asm.getOrCreateSectionData(*StrtabSection);
StrtabSD.setAlignment(1);
-
- ComputeIndexMap(Asm, SectionIndexMap, RelMap);
-
- ShstrtabIndex = SectionIndexMap.lookup(ShstrtabSection);
- SymbolTableIndex = SectionIndexMap.lookup(SymtabSection);
- StringTableIndex = SectionIndexMap.lookup(StrtabSection);
+ StringTableIndex = SectionIndexMap.size() + 1;
+ SectionIndexMap[StrtabSection] = StringTableIndex;
// Symbol table
F = new MCDataFragment(&SymtabSD);
static_cast<const MCSectionELF&>(it->getSection());
ShStrTabBuilder.add(Section.getSectionName());
}
- ShStrTabBuilder.finalize();
+ ShStrTabBuilder.finalize(StringTableBuilder::ELF);
F->getContents().append(ShStrTabBuilder.data().begin(),
ShStrTabBuilder.data().end());
}
-void ELFObjectWriter::CreateIndexedSections(MCAssembler &Asm,
+void ELFObjectWriter::createIndexedSections(MCAssembler &Asm,
MCAsmLayout &Layout,
GroupMapTy &GroupMap,
RevGroupMapTy &RevGroupMap,
SectionIndexMapTy &SectionIndexMap,
- const RelMapTy &RelMap) {
- // Create the .note.GNU-stack section if needed.
+ RelMapTy &RelMap) {
MCContext &Ctx = Asm.getContext();
- if (Asm.getNoExecStack()) {
- const MCSectionELF *GnuStackSection =
- Ctx.getELFSection(".note.GNU-stack", ELF::SHT_PROGBITS, 0,
- SectionKind::getReadOnly());
- Asm.getOrCreateSectionData(*GnuStackSection);
- }
// Build the groups
for (MCAssembler::const_iterator it = Asm.begin(), ie = Asm.end();
GroupMap[Group] = SignatureSymbol;
}
- ComputeIndexMap(Asm, SectionIndexMap, RelMap);
+ computeIndexMap(Asm, SectionIndexMap, RelMap);
// Add sections to the groups
for (MCAssembler::const_iterator it = Asm.begin(), ie = Asm.end();
}
}
-void ELFObjectWriter::WriteSection(MCAssembler &Asm,
+void ELFObjectWriter::writeSection(MCAssembler &Asm,
const SectionIndexMapTy &SectionIndexMap,
+ const RelMapTy &RelMap,
uint32_t GroupSymbolIndex,
uint64_t Offset, uint64_t Size,
uint64_t Alignment,
case ELF::SHT_REL:
case ELF::SHT_RELA: {
- const MCSectionELF *SymtabSection;
- const MCSectionELF *InfoSection;
- SymtabSection = Asm.getContext().getELFSection(".symtab", ELF::SHT_SYMTAB,
- 0,
- SectionKind::getReadOnly());
- sh_link = SectionIndexMap.lookup(SymtabSection);
+ sh_link = SymbolTableIndex;
assert(sh_link && ".symtab not found");
-
- // Remove ".rel" and ".rela" prefixes.
- unsigned SecNameLen = (Section.getType() == ELF::SHT_REL) ? 4 : 5;
- StringRef SectionName = Section.getSectionName().substr(SecNameLen);
- StringRef GroupName =
- Section.getGroup() ? Section.getGroup()->getName() : "";
-
- InfoSection = Asm.getContext().getELFSection(SectionName, ELF::SHT_PROGBITS,
- 0, SectionKind::getReadOnly(),
- 0, GroupName);
+ const MCSectionELF *InfoSection = RelMap.find(&Section)->second;
sh_info = SectionIndexMap.lookup(InfoSection);
break;
}
case ELF::SHT_X86_64_UNWIND:
case ELF::SHT_MIPS_REGINFO:
case ELF::SHT_MIPS_OPTIONS:
+ case ELF::SHT_MIPS_ABIFLAGS:
// Nothing to do.
break;
break;
default:
- assert(0 && "FIXME: sh_type value not supported!");
- break;
+ llvm_unreachable("FIXME: sh_type value not supported!");
}
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()));
+ sh_link = SectionIndexMap.lookup(Asm.getContext().getELFSection(
+ ".text", ELF::SHT_PROGBITS, ELF::SHF_EXECINSTR | ELF::SHF_ALLOC));
} else if (SecName.startswith(".ARM.exidx")) {
StringRef GroupName =
Section.getGroup() ? Section.getGroup()->getName() : "";
sh_link = SectionIndexMap.lookup(Asm.getContext().getELFSection(
SecName.substr(sizeof(".ARM.exidx") - 1), ELF::SHT_PROGBITS,
- ELF::SHF_EXECINSTR | ELF::SHF_ALLOC, SectionKind::getText(), 0,
- GroupName));
+ ELF::SHF_EXECINSTR | ELF::SHF_ALLOC, 0, GroupName));
}
}
}
}
-void ELFObjectWriter::WriteSectionHeader(MCAssembler &Asm,
- const GroupMapTy &GroupMap,
- const MCAsmLayout &Layout,
- const SectionIndexMapTy &SectionIndexMap,
- const SectionOffsetMapTy &SectionOffsetMap) {
+void ELFObjectWriter::writeSectionHeader(
+ MCAssembler &Asm, const GroupMapTy &GroupMap, const MCAsmLayout &Layout,
+ const SectionIndexMapTy &SectionIndexMap, const RelMapTy &RelMap,
+ const SectionOffsetMapTy &SectionOffsetMap) {
const unsigned NumSections = Asm.size() + 1;
std::vector<const MCSectionELF*> Sections;
uint64_t Size = GetSectionAddressSize(Layout, SD);
- WriteSection(Asm, SectionIndexMap, GroupSymbolIndex,
+ writeSection(Asm, SectionIndexMap, RelMap, GroupSymbolIndex,
SectionOffsetMap.lookup(&Section), Size,
SD.getAlignment(), Section);
}
CompressDebugSections(Asm, const_cast<MCAsmLayout &>(Layout));
DenseMap<const MCSectionELF*, const MCSectionELF*> RelMap;
- CreateRelocationSections(Asm, const_cast<MCAsmLayout&>(Layout), RelMap);
-
const unsigned NumUserAndRelocSections = Asm.size();
- CreateIndexedSections(Asm, const_cast<MCAsmLayout&>(Layout), GroupMap,
+ createIndexedSections(Asm, const_cast<MCAsmLayout&>(Layout), GroupMap,
RevGroupMap, SectionIndexMap, RelMap);
const unsigned AllSections = Asm.size();
const unsigned NumIndexedSections = AllSections - NumUserAndRelocSections;
CreateMetadataSections(const_cast<MCAssembler&>(Asm),
const_cast<MCAsmLayout&>(Layout),
- SectionIndexMap,
- RelMap);
+ SectionIndexMap);
uint64_t NaturalAlignment = is64Bit() ? 8 : 4;
uint64_t HeaderSize = is64Bit() ? sizeof(ELF::Elf64_Ehdr) :
WriteZeros(Padding);
// ... then the section header table ...
- WriteSectionHeader(Asm, GroupMap, Layout, SectionIndexMap,
+ writeSectionHeader(Asm, GroupMap, Layout, SectionIndexMap, RelMap,
SectionOffsetMap);
// ... and then the remaining sections ...
const MCFragment &FB,
bool InSet,
bool IsPCRel) const {
- if (DataA.getFlags() & ELF_STB_Weak || MCELF::GetType(DataA) == ELF::STT_GNU_IFUNC)
+ if (::isWeak(DataA))
return false;
return MCObjectWriter::IsSymbolRefDifferenceFullyResolvedImpl(
Asm, DataA, FB,InSet, IsPCRel);
}
+bool ELFObjectWriter::isWeak(const MCSymbolData &SD) const {
+ return ::isWeak(SD);
+}
+
MCObjectWriter *llvm::createELFObjectWriter(MCELFObjectTargetWriter *MOTW,
raw_ostream &OS,
bool IsLittleEndian) {
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