From 1c98619801a5705c688e683be3ef9d70169a0686 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Sat, 23 Jul 2016 20:48:50 +0000 Subject: Vendor import of lld release_39 branch r276489: https://llvm.org/svn/llvm-project/lld/branches/release_39@276489 --- ELF/OutputSections.cpp | 2176 ++++++++++++++++++++++++++++-------------------- 1 file changed, 1289 insertions(+), 887 deletions(-) (limited to 'ELF/OutputSections.cpp') diff --git a/ELF/OutputSections.cpp b/ELF/OutputSections.cpp index 2aa814524d6b..50b94015f229 100644 --- a/ELF/OutputSections.cpp +++ b/ELF/OutputSections.cpp @@ -9,19 +9,26 @@ #include "OutputSections.h" #include "Config.h" +#include "EhFrame.h" +#include "LinkerScript.h" +#include "Strings.h" #include "SymbolTable.h" #include "Target.h" +#include "lld/Core/Parallel.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/MD5.h" #include "llvm/Support/MathExtras.h" +#include "llvm/Support/SHA1.h" +#include using namespace llvm; +using namespace llvm::dwarf; using namespace llvm::object; using namespace llvm::support::endian; using namespace llvm::ELF; using namespace lld; -using namespace lld::elf2; - -bool elf2::HasGotOffRel = false; +using namespace lld::elf; template OutputSectionBase::OutputSectionBase(StringRef Name, uint32_t Type, @@ -30,39 +37,39 @@ OutputSectionBase::OutputSectionBase(StringRef Name, uint32_t Type, memset(&Header, 0, sizeof(Elf_Shdr)); Header.sh_type = Type; Header.sh_flags = Flags; + Header.sh_addralign = 1; +} + +template +void OutputSectionBase::writeHeaderTo(Elf_Shdr *Shdr) { + *Shdr = Header; } template GotPltSection::GotPltSection() : OutputSectionBase(".got.plt", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE) { - this->Header.sh_addralign = sizeof(uintX_t); + this->Header.sh_addralign = Target->GotPltEntrySize; } -template void GotPltSection::addEntry(SymbolBody *Sym) { - Sym->GotPltIndex = Target->getGotPltHeaderEntriesNum() + Entries.size(); - Entries.push_back(Sym); +template void GotPltSection::addEntry(SymbolBody &Sym) { + Sym.GotPltIndex = Target->GotPltHeaderEntriesNum + Entries.size(); + Entries.push_back(&Sym); } template bool GotPltSection::empty() const { return Entries.empty(); } -template -typename GotPltSection::uintX_t -GotPltSection::getEntryAddr(const SymbolBody &B) const { - return this->getVA() + B.GotPltIndex * sizeof(uintX_t); -} - template void GotPltSection::finalize() { - this->Header.sh_size = - (Target->getGotPltHeaderEntriesNum() + Entries.size()) * sizeof(uintX_t); + this->Header.sh_size = (Target->GotPltHeaderEntriesNum + Entries.size()) * + Target->GotPltEntrySize; } template void GotPltSection::writeTo(uint8_t *Buf) { - Target->writeGotPltHeaderEntries(Buf); - Buf += Target->getGotPltHeaderEntriesNum() * sizeof(uintX_t); + Target->writeGotPltHeader(Buf); + Buf += Target->GotPltHeaderEntriesNum * Target->GotPltEntrySize; for (const SymbolBody *B : Entries) { - Target->writeGotPltEntry(Buf, Out::Plt->getEntryAddr(*B)); + Target->writeGotPlt(Buf, *B); Buf += sizeof(uintX_t); } } @@ -72,37 +79,135 @@ GotSection::GotSection() : OutputSectionBase(".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE) { if (Config->EMachine == EM_MIPS) this->Header.sh_flags |= SHF_MIPS_GPREL; - this->Header.sh_addralign = sizeof(uintX_t); + this->Header.sh_addralign = Target->GotEntrySize; } -template void GotSection::addEntry(SymbolBody *Sym) { - Sym->GotIndex = Target->getGotHeaderEntriesNum() + Entries.size(); - Entries.push_back(Sym); +template +void GotSection::addEntry(SymbolBody &Sym) { + Sym.GotIndex = Entries.size(); + Entries.push_back(&Sym); } -template bool GotSection::addDynTlsEntry(SymbolBody *Sym) { - if (Sym->hasGlobalDynIndex()) +template +void GotSection::addMipsEntry(SymbolBody &Sym, uintX_t Addend, + RelExpr Expr) { + // For "true" local symbols which can be referenced from the same module + // only compiler creates two instructions for address loading: + // + // lw $8, 0($gp) # R_MIPS_GOT16 + // addi $8, $8, 0 # R_MIPS_LO16 + // + // The first instruction loads high 16 bits of the symbol address while + // the second adds an offset. That allows to reduce number of required + // GOT entries because only one global offset table entry is necessary + // for every 64 KBytes of local data. So for local symbols we need to + // allocate number of GOT entries to hold all required "page" addresses. + // + // All global symbols (hidden and regular) considered by compiler uniformly. + // It always generates a single `lw` instruction and R_MIPS_GOT16 relocation + // to load address of the symbol. So for each such symbol we need to + // allocate dedicated GOT entry to store its address. + // + // If a symbol is preemptible we need help of dynamic linker to get its + // final address. The corresponding GOT entries are allocated in the + // "global" part of GOT. Entries for non preemptible global symbol allocated + // in the "local" part of GOT. + // + // See "Global Offset Table" in Chapter 5: + // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf + if (Expr == R_MIPS_GOT_LOCAL_PAGE) { + // At this point we do not know final symbol value so to reduce number + // of allocated GOT entries do the following trick. Save all output + // sections referenced by GOT relocations. Then later in the `finalize` + // method calculate number of "pages" required to cover all saved output + // section and allocate appropriate number of GOT entries. + auto *OutSec = cast>(&Sym)->Section->OutSec; + MipsOutSections.insert(OutSec); + return; + } + if (Sym.isTls()) { + // GOT entries created for MIPS TLS relocations behave like + // almost GOT entries from other ABIs. They go to the end + // of the global offset table. + Sym.GotIndex = Entries.size(); + Entries.push_back(&Sym); + return; + } + auto AddEntry = [&](SymbolBody &S, uintX_t A, MipsGotEntries &Items) { + if (S.isInGot() && !A) + return; + size_t NewIndex = Items.size(); + if (!MipsGotMap.insert({{&S, A}, NewIndex}).second) + return; + Items.emplace_back(&S, A); + if (!A) + S.GotIndex = NewIndex; + }; + if (Sym.isPreemptible()) { + // Ignore addends for preemptible symbols. They got single GOT entry anyway. + AddEntry(Sym, 0, MipsGlobal); + Sym.IsInGlobalMipsGot = true; + } else + AddEntry(Sym, Addend, MipsLocal); +} + +template bool GotSection::addDynTlsEntry(SymbolBody &Sym) { + if (Sym.GlobalDynIndex != -1U) return false; - Sym->GlobalDynIndex = Target->getGotHeaderEntriesNum() + Entries.size(); + Sym.GlobalDynIndex = Entries.size(); // Global Dynamic TLS entries take two GOT slots. - Entries.push_back(Sym); Entries.push_back(nullptr); + Entries.push_back(&Sym); return true; } -template bool GotSection::addCurrentModuleTlsIndex() { - if (LocalTlsIndexOff != uint32_t(-1)) +// Reserves TLS entries for a TLS module ID and a TLS block offset. +// In total it takes two GOT slots. +template bool GotSection::addTlsIndex() { + if (TlsIndexOff != uint32_t(-1)) return false; + TlsIndexOff = Entries.size() * sizeof(uintX_t); Entries.push_back(nullptr); Entries.push_back(nullptr); - LocalTlsIndexOff = (Entries.size() - 2) * sizeof(uintX_t); return true; } template typename GotSection::uintX_t -GotSection::getEntryAddr(const SymbolBody &B) const { - return this->getVA() + B.GotIndex * sizeof(uintX_t); +GotSection::getMipsLocalPageOffset(uintX_t EntryValue) { + // Initialize the entry by the %hi(EntryValue) expression + // but without right-shifting. + EntryValue = (EntryValue + 0x8000) & ~0xffff; + // Take into account MIPS GOT header. + // See comment in the GotSection::writeTo. + size_t NewIndex = MipsLocalGotPos.size() + 2; + auto P = MipsLocalGotPos.insert(std::make_pair(EntryValue, NewIndex)); + assert(!P.second || MipsLocalGotPos.size() <= MipsPageEntries); + return (uintX_t)P.first->second * sizeof(uintX_t) - MipsGPOffset; +} + +template +typename GotSection::uintX_t +GotSection::getMipsGotOffset(const SymbolBody &B, uintX_t Addend) const { + uintX_t Off = MipsPageEntries; + if (B.isTls()) + Off += MipsLocal.size() + MipsGlobal.size() + B.GotIndex; + else if (B.IsInGlobalMipsGot) + Off += MipsLocal.size() + B.GotIndex; + else if (B.isInGot()) + Off += B.GotIndex; + else { + auto It = MipsGotMap.find({&B, Addend}); + assert(It != MipsGotMap.end()); + Off += It->second; + } + return Off * sizeof(uintX_t) - MipsGPOffset; +} + +template +typename GotSection::uintX_t GotSection::getMipsTlsOffset() { + return (MipsPageEntries + MipsLocal.size() + MipsGlobal.size()) * + sizeof(uintX_t); } template @@ -111,38 +216,86 @@ GotSection::getGlobalDynAddr(const SymbolBody &B) const { return this->getVA() + B.GlobalDynIndex * sizeof(uintX_t); } +template +typename GotSection::uintX_t +GotSection::getGlobalDynOffset(const SymbolBody &B) const { + return B.GlobalDynIndex * sizeof(uintX_t); +} + template const SymbolBody *GotSection::getMipsFirstGlobalEntry() const { - return Entries.empty() ? nullptr : Entries.front(); + return MipsGlobal.empty() ? nullptr : MipsGlobal.front().first; } template unsigned GotSection::getMipsLocalEntriesNum() const { - // TODO: Update when the support of GOT entries for local symbols is added. - return Target->getGotHeaderEntriesNum(); + return MipsPageEntries + MipsLocal.size(); } template void GotSection::finalize() { - this->Header.sh_size = - (Target->getGotHeaderEntriesNum() + Entries.size()) * sizeof(uintX_t); + size_t EntriesNum = Entries.size(); + if (Config->EMachine == EM_MIPS) { + // Take into account MIPS GOT header. + // See comment in the GotSection::writeTo. + MipsPageEntries += 2; + for (const OutputSectionBase *OutSec : MipsOutSections) { + // Calculate an upper bound of MIPS GOT entries required to store page + // addresses of local symbols. We assume the worst case - each 64kb + // page of the output section has at least one GOT relocation against it. + // Add 0x8000 to the section's size because the page address stored + // in the GOT entry is calculated as (value + 0x8000) & ~0xffff. + MipsPageEntries += (OutSec->getSize() + 0x8000 + 0xfffe) / 0xffff; + } + EntriesNum += MipsPageEntries + MipsLocal.size() + MipsGlobal.size(); + } + this->Header.sh_size = EntriesNum * sizeof(uintX_t); +} + +template void GotSection::writeMipsGot(uint8_t *&Buf) { + // Set the MSB of the second GOT slot. This is not required by any + // MIPS ABI documentation, though. + // + // There is a comment in glibc saying that "The MSB of got[1] of a + // gnu object is set to identify gnu objects," and in GNU gold it + // says "the second entry will be used by some runtime loaders". + // But how this field is being used is unclear. + // + // We are not really willing to mimic other linkers behaviors + // without understanding why they do that, but because all files + // generated by GNU tools have this special GOT value, and because + // we've been doing this for years, it is probably a safe bet to + // keep doing this for now. We really need to revisit this to see + // if we had to do this. + auto *P = reinterpret_cast(Buf); + P[1] = uintX_t(1) << (ELFT::Is64Bits ? 63 : 31); + // Write 'page address' entries to the local part of the GOT. + for (std::pair &L : MipsLocalGotPos) { + uint8_t *Entry = Buf + L.second * sizeof(uintX_t); + write(Entry, L.first); + } + Buf += MipsPageEntries * sizeof(uintX_t); + auto AddEntry = [&](const MipsGotEntry &SA) { + uint8_t *Entry = Buf; + Buf += sizeof(uintX_t); + const SymbolBody* Body = SA.first; + uintX_t VA = Body->template getVA(SA.second); + write(Entry, VA); + }; + std::for_each(std::begin(MipsLocal), std::end(MipsLocal), AddEntry); + std::for_each(std::begin(MipsGlobal), std::end(MipsGlobal), AddEntry); } template void GotSection::writeTo(uint8_t *Buf) { - Target->writeGotHeaderEntries(Buf); - Buf += Target->getGotHeaderEntriesNum() * sizeof(uintX_t); + if (Config->EMachine == EM_MIPS) + writeMipsGot(Buf); for (const SymbolBody *B : Entries) { uint8_t *Entry = Buf; Buf += sizeof(uintX_t); if (!B) continue; - // MIPS has special rules to fill up GOT entries. - // See "Global Offset Table" in Chapter 5 in the following document - // for detailed description: - // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf - // As the first approach, we can just store addresses for all symbols. - if (Config->EMachine != EM_MIPS && canBePreempted(B, false)) + if (B->isPreemptible()) continue; // The dynamic linker will take care of it. - uintX_t VA = getSymVA(*B); + uintX_t VA = B->getVA(); write(Entry, VA); } } @@ -154,165 +307,81 @@ PltSection::PltSection() } template void PltSection::writeTo(uint8_t *Buf) { - size_t Off = 0; - bool LazyReloc = Target->supportsLazyRelocations(); - if (LazyReloc) { - // First write PLT[0] entry which is special. - Target->writePltZeroEntry(Buf, Out::GotPlt->getVA(), this->getVA()); - Off += Target->getPltZeroEntrySize(); - } + // At beginning of PLT, we have code to call the dynamic linker + // to resolve dynsyms at runtime. Write such code. + Target->writePltHeader(Buf); + size_t Off = Target->PltHeaderSize; + for (auto &I : Entries) { - const SymbolBody *E = I.first; + const SymbolBody *B = I.first; unsigned RelOff = I.second; - uint64_t GotVA = - LazyReloc ? Out::GotPlt->getVA() : Out::Got->getVA(); - uint64_t GotE = LazyReloc ? Out::GotPlt->getEntryAddr(*E) - : Out::Got->getEntryAddr(*E); + uint64_t Got = B->getGotPltVA(); uint64_t Plt = this->getVA() + Off; - Target->writePltEntry(Buf + Off, GotVA, GotE, Plt, E->PltIndex, RelOff); - Off += Target->getPltEntrySize(); + Target->writePlt(Buf + Off, Got, Plt, B->PltIndex, RelOff); + Off += Target->PltEntrySize; } } -template void PltSection::addEntry(SymbolBody *Sym) { - Sym->PltIndex = Entries.size(); - unsigned RelOff = Target->supportsLazyRelocations() - ? Out::RelaPlt->getRelocOffset() - : Out::RelaDyn->getRelocOffset(); - Entries.push_back(std::make_pair(Sym, RelOff)); -} - -template -typename PltSection::uintX_t -PltSection::getEntryAddr(const SymbolBody &B) const { - return this->getVA() + Target->getPltZeroEntrySize() + - B.PltIndex * Target->getPltEntrySize(); +template void PltSection::addEntry(SymbolBody &Sym) { + Sym.PltIndex = Entries.size(); + unsigned RelOff = Out::RelaPlt->getRelocOffset(); + Entries.push_back(std::make_pair(&Sym, RelOff)); } template void PltSection::finalize() { - this->Header.sh_size = Target->getPltZeroEntrySize() + - Entries.size() * Target->getPltEntrySize(); + this->Header.sh_size = + Target->PltHeaderSize + Entries.size() * Target->PltEntrySize; } template -RelocationSection::RelocationSection(StringRef Name, bool IsRela) - : OutputSectionBase(Name, IsRela ? SHT_RELA : SHT_REL, SHF_ALLOC), - IsRela(IsRela) { - this->Header.sh_entsize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel); - this->Header.sh_addralign = ELFT::Is64Bits ? 8 : 4; +RelocationSection::RelocationSection(StringRef Name, bool Sort) + : OutputSectionBase(Name, Config->Rela ? SHT_RELA : SHT_REL, + SHF_ALLOC), + Sort(Sort) { + this->Header.sh_entsize = Config->Rela ? sizeof(Elf_Rela) : sizeof(Elf_Rel); + this->Header.sh_addralign = sizeof(uintX_t); } -// Applies corresponding symbol and type for dynamic tls relocation. -// Returns true if relocation was handled. template -bool RelocationSection::applyTlsDynamicReloc(SymbolBody *Body, - uint32_t Type, Elf_Rel *P, - Elf_Rel *N) { - if (Target->isTlsLocalDynamicReloc(Type)) { - P->setSymbolAndType(0, Target->getTlsModuleIndexReloc(), Config->Mips64EL); - P->r_offset = Out::Got->getLocalTlsIndexVA(); - return true; - } - - if (!Body || !Target->isTlsGlobalDynamicReloc(Type)) - return false; - - if (Target->isTlsOptimized(Type, Body)) { - P->setSymbolAndType(Body->DynamicSymbolTableIndex, - Target->getTlsGotReloc(), Config->Mips64EL); - P->r_offset = Out::Got->getEntryAddr(*Body); - return true; - } +void RelocationSection::addReloc(const DynamicReloc &Reloc) { + Relocs.push_back(Reloc); +} - P->setSymbolAndType(Body->DynamicSymbolTableIndex, - Target->getTlsModuleIndexReloc(), Config->Mips64EL); - P->r_offset = Out::Got->getGlobalDynAddr(*Body); - N->setSymbolAndType(Body->DynamicSymbolTableIndex, - Target->getTlsOffsetReloc(), Config->Mips64EL); - N->r_offset = Out::Got->getGlobalDynAddr(*Body) + sizeof(uintX_t); - return true; +template +static bool compRelocations(const RelTy &A, const RelTy &B) { + return A.getSymbol(Config->Mips64EL) < B.getSymbol(Config->Mips64EL); } template void RelocationSection::writeTo(uint8_t *Buf) { + uint8_t *BufBegin = Buf; for (const DynamicReloc &Rel : Relocs) { - auto *P = reinterpret_cast(Buf); - Buf += IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel); - - // Skip placeholder for global dynamic TLS relocation pair. It was already - // handled by the previous relocation. - if (!Rel.C) - continue; - - InputSectionBase &C = *Rel.C; - const Elf_Rel &RI = *Rel.RI; - uint32_t SymIndex = RI.getSymbol(Config->Mips64EL); - const ObjectFile &File = *C.getFile(); - SymbolBody *Body = File.getSymbolBody(SymIndex); - if (Body) - Body = Body->repl(); + auto *P = reinterpret_cast(Buf); + Buf += Config->Rela ? sizeof(Elf_Rela) : sizeof(Elf_Rel); + + if (Config->Rela) + P->r_addend = Rel.getAddend(); + P->r_offset = Rel.getOffset(); + if (Config->EMachine == EM_MIPS && Rel.getOutputSec() == Out::Got) + // Dynamic relocation against MIPS GOT section make deal TLS entries + // allocated in the end of the GOT. We need to adjust the offset to take + // in account 'local' and 'global' GOT entries. + P->r_offset += Out::Got->getMipsTlsOffset(); + P->setSymbolAndType(Rel.getSymIndex(), Rel.Type, Config->Mips64EL); + } - uint32_t Type = RI.getType(Config->Mips64EL); - if (applyTlsDynamicReloc(Body, Type, P, reinterpret_cast(Buf))) - continue; - bool NeedsCopy = Body && Target->needsCopyRel(Type, *Body); - bool NeedsGot = Body && Target->relocNeedsGot(Type, *Body); - bool CBP = canBePreempted(Body, NeedsGot); - bool LazyReloc = Body && Target->supportsLazyRelocations() && - Target->relocNeedsPlt(Type, *Body); - bool IsDynRelative = Type == Target->getRelativeReloc(); - - unsigned Sym = CBP ? Body->DynamicSymbolTableIndex : 0; - unsigned Reloc; - if (!CBP && Body && isGnuIFunc(*Body)) - Reloc = Target->getIRelativeReloc(); - else if (!CBP || IsDynRelative) - Reloc = Target->getRelativeReloc(); - else if (LazyReloc) - Reloc = Target->getPltReloc(); - else if (NeedsGot) - Reloc = Body->isTls() ? Target->getTlsGotReloc() : Target->getGotReloc(); - else if (NeedsCopy) - Reloc = Target->getCopyReloc(); - else - Reloc = Target->getDynReloc(Type); - P->setSymbolAndType(Sym, Reloc, Config->Mips64EL); - - if (LazyReloc) - P->r_offset = Out::GotPlt->getEntryAddr(*Body); - else if (NeedsGot) - P->r_offset = Out::Got->getEntryAddr(*Body); - else if (NeedsCopy) - P->r_offset = Out::Bss->getVA() + - cast>(Body)->OffsetInBss; - else - P->r_offset = C.getOffset(RI.r_offset) + C.OutSec->getVA(); - - uintX_t OrigAddend = 0; - if (IsRela && !NeedsGot) - OrigAddend = static_cast(RI).r_addend; - - uintX_t Addend; - if (NeedsCopy) - Addend = 0; - else if (CBP || IsDynRelative) - Addend = OrigAddend; - else if (Body) - Addend = getSymVA(*Body) + OrigAddend; - else if (IsRela) - Addend = - getLocalRelTarget(File, static_cast(RI), - getAddend(static_cast(RI))); + if (Sort) { + if (Config->Rela) + std::stable_sort((Elf_Rela *)BufBegin, + (Elf_Rela *)BufBegin + Relocs.size(), + compRelocations); else - Addend = getLocalRelTarget(File, RI, 0); - - if (IsRela) - static_cast(P)->r_addend = Addend; + std::stable_sort((Elf_Rel *)BufBegin, (Elf_Rel *)BufBegin + Relocs.size(), + compRelocations); } } template unsigned RelocationSection::getRelocOffset() { - const unsigned EntrySize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel); - return EntrySize * Relocs.size(); + return this->Header.sh_entsize * Relocs.size(); } template void RelocationSection::finalize() { @@ -325,17 +394,11 @@ template InterpSection::InterpSection() : OutputSectionBase(".interp", SHT_PROGBITS, SHF_ALLOC) { this->Header.sh_size = Config->DynamicLinker.size() + 1; - this->Header.sh_addralign = 1; -} - -template -void OutputSectionBase::writeHeaderTo(Elf_Shdr *SHdr) { - Header.sh_name = Out::ShStrTab->addString(Name); - *SHdr = Header; } template void InterpSection::writeTo(uint8_t *Buf) { - memcpy(Buf, Config->DynamicLinker.data(), Config->DynamicLinker.size()); + StringRef S = Config->DynamicLinker; + memcpy(Buf, S.data(), S.size()); } template @@ -360,7 +423,7 @@ static uint32_t hashSysv(StringRef Name) { template void HashTableSection::finalize() { this->Header.sh_link = Out::DynSymTab->SectionIndex; - unsigned NumEntries = 2; // nbucket and nchain. + unsigned NumEntries = 2; // nbucket and nchain. NumEntries += Out::DynSymTab->getNumSymbols(); // The chain entries. // Create as many buckets as there are symbols. @@ -379,9 +442,11 @@ template void HashTableSection::writeTo(uint8_t *Buf) { Elf_Word *Buckets = P; Elf_Word *Chains = P + NumSymbols; - for (SymbolBody *Body : Out::DynSymTab->getSymbols()) { + for (const std::pair &P : + Out::DynSymTab->getSymbols()) { + SymbolBody *Body = P.first; StringRef Name = Body->getName(); - unsigned I = Body->DynamicSymbolTableIndex; + unsigned I = Body->DynsymIndex; uint32_t Hash = hashSysv(Name) % NumSymbols; Chains[I] = Buckets[Hash]; Buckets[Hash] = I; @@ -399,7 +464,7 @@ template GnuHashTableSection::GnuHashTableSection() : OutputSectionBase(".gnu.hash", SHT_GNU_HASH, SHF_ALLOC) { this->Header.sh_entsize = ELFT::Is64Bits ? 0 : 4; - this->Header.sh_addralign = ELFT::Is64Bits ? 8 : 4; + this->Header.sh_addralign = sizeof(uintX_t); } template @@ -437,7 +502,7 @@ unsigned GnuHashTableSection::calcMaskWords(unsigned NumHashed) { } template void GnuHashTableSection::finalize() { - unsigned NumHashed = HashedSymbols.size(); + unsigned NumHashed = Symbols.size(); NBuckets = calcNBuckets(NumHashed); MaskWords = calcMaskWords(NumHashed); // Second hash shift estimation: just predefined values. @@ -452,7 +517,7 @@ template void GnuHashTableSection::finalize() { template void GnuHashTableSection::writeTo(uint8_t *Buf) { writeHeader(Buf); - if (HashedSymbols.empty()) + if (Symbols.empty()) return; writeBloomFilter(Buf); writeHashTable(Buf); @@ -462,7 +527,7 @@ template void GnuHashTableSection::writeHeader(uint8_t *&Buf) { auto *P = reinterpret_cast(Buf); *P++ = NBuckets; - *P++ = Out::DynSymTab->getNumSymbols() - HashedSymbols.size(); + *P++ = Out::DynSymTab->getNumSymbols() - Symbols.size(); *P++ = MaskWords; *P++ = Shift2; Buf = reinterpret_cast(P); @@ -473,10 +538,10 @@ void GnuHashTableSection::writeBloomFilter(uint8_t *&Buf) { unsigned C = sizeof(Elf_Off) * 8; auto *Masks = reinterpret_cast(Buf); - for (const HashedSymbolData &Item : HashedSymbols) { - size_t Pos = (Item.Hash / C) & (MaskWords - 1); - uintX_t V = (uintX_t(1) << (Item.Hash % C)) | - (uintX_t(1) << ((Item.Hash >> Shift2) % C)); + for (const SymbolData &Sym : Symbols) { + size_t Pos = (Sym.Hash / C) & (MaskWords - 1); + uintX_t V = (uintX_t(1) << (Sym.Hash % C)) | + (uintX_t(1) << ((Sym.Hash >> Shift2) % C)); Masks[Pos] |= V; } Buf += sizeof(Elf_Off) * MaskWords; @@ -489,58 +554,64 @@ void GnuHashTableSection::writeHashTable(uint8_t *Buf) { int PrevBucket = -1; int I = 0; - for (const HashedSymbolData &Item : HashedSymbols) { - int Bucket = Item.Hash % NBuckets; + for (const SymbolData &Sym : Symbols) { + int Bucket = Sym.Hash % NBuckets; assert(PrevBucket <= Bucket); if (Bucket != PrevBucket) { - Buckets[Bucket] = Item.Body->DynamicSymbolTableIndex; + Buckets[Bucket] = Sym.Body->DynsymIndex; PrevBucket = Bucket; if (I > 0) Values[I - 1] |= 1; } - Values[I] = Item.Hash & ~1; + Values[I] = Sym.Hash & ~1; ++I; } if (I > 0) Values[I - 1] |= 1; } -static bool includeInGnuHashTable(SymbolBody *B) { - // Assume that includeInDynamicSymtab() is already checked. - return !B->isUndefined(); -} - +// Add symbols to this symbol hash table. Note that this function +// destructively sort a given vector -- which is needed because +// GNU-style hash table places some sorting requirements. template -void GnuHashTableSection::addSymbols(std::vector &Symbols) { - std::vector NotHashed; - NotHashed.reserve(Symbols.size()); - HashedSymbols.reserve(Symbols.size()); - for (SymbolBody *B : Symbols) { - if (includeInGnuHashTable(B)) - HashedSymbols.push_back(HashedSymbolData{B, hashGnu(B->getName())}); - else - NotHashed.push_back(B); - } - if (HashedSymbols.empty()) +void GnuHashTableSection::addSymbols( + std::vector> &V) { + // Ideally this will just be 'auto' but GCC 6.1 is not able + // to deduce it correctly. + std::vector>::iterator Mid = + std::stable_partition(V.begin(), V.end(), + [](std::pair &P) { + return P.first->isUndefined(); + }); + if (Mid == V.end()) return; + for (auto I = Mid, E = V.end(); I != E; ++I) { + SymbolBody *B = I->first; + size_t StrOff = I->second; + Symbols.push_back({B, StrOff, hashGnu(B->getName())}); + } - unsigned NBuckets = calcNBuckets(HashedSymbols.size()); - std::stable_sort(HashedSymbols.begin(), HashedSymbols.end(), - [&](const HashedSymbolData &L, const HashedSymbolData &R) { + unsigned NBuckets = calcNBuckets(Symbols.size()); + std::stable_sort(Symbols.begin(), Symbols.end(), + [&](const SymbolData &L, const SymbolData &R) { return L.Hash % NBuckets < R.Hash % NBuckets; }); - Symbols = std::move(NotHashed); - for (const HashedSymbolData &Item : HashedSymbols) - Symbols.push_back(Item.Body); + V.erase(Mid, V.end()); + for (const SymbolData &Sym : Symbols) + V.push_back({Sym.Body, Sym.STName}); } +// Returns the number of version definition entries. Because the first entry +// is for the version definition itself, it is the number of versioned symbols +// plus one. Note that we don't support multiple versions yet. +static unsigned getVerDefNum() { return Config->VersionDefinitions.size() + 1; } + template -DynamicSection::DynamicSection(SymbolTable &SymTab) - : OutputSectionBase(".dynamic", SHT_DYNAMIC, SHF_ALLOC | SHF_WRITE), - SymTab(SymTab) { +DynamicSection::DynamicSection() + : OutputSectionBase(".dynamic", SHT_DYNAMIC, SHF_ALLOC | SHF_WRITE) { Elf_Shdr &Header = this->Header; - Header.sh_addralign = ELFT::Is64Bits ? 8 : 4; + Header.sh_addralign = sizeof(uintX_t); Header.sh_entsize = ELFT::Is64Bits ? 16 : 8; // .dynamic section is not writable on MIPS. @@ -557,61 +628,66 @@ template void DynamicSection::finalize() { Elf_Shdr &Header = this->Header; Header.sh_link = Out::DynStrTab->SectionIndex; - unsigned NumEntries = 0; + auto Add = [=](Entry E) { Entries.push_back(E); }; + + // Add strings. We know that these are the last strings to be added to + // DynStrTab and doing this here allows this function to set DT_STRSZ. + if (!Config->RPath.empty()) + Add({Config->EnableNewDtags ? DT_RUNPATH : DT_RPATH, + Out::DynStrTab->addString(Config->RPath)}); + for (const std::unique_ptr> &F : + Symtab::X->getSharedFiles()) + if (F->isNeeded()) + Add({DT_NEEDED, Out::DynStrTab->addString(F->getSoName())}); + if (!Config->SoName.empty()) + Add({DT_SONAME, Out::DynStrTab->addString(Config->SoName)}); + + Out::DynStrTab->finalize(); + if (Out::RelaDyn->hasRelocs()) { - ++NumEntries; // DT_RELA / DT_REL - ++NumEntries; // DT_RELASZ / DT_RELSZ - ++NumEntries; // DT_RELAENT / DT_RELENT + bool IsRela = Config->Rela; + Add({IsRela ? DT_RELA : DT_REL, Out::RelaDyn}); + Add({IsRela ? DT_RELASZ : DT_RELSZ, Out::RelaDyn->getSize()}); + Add({IsRela ? DT_RELAENT : DT_RELENT, + uintX_t(IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel))}); } if (Out::RelaPlt && Out::RelaPlt->hasRelocs()) { - ++NumEntries; // DT_JMPREL - ++NumEntries; // DT_PLTRELSZ - ++NumEntries; // DT_PLTGOT / DT_MIPS_PLTGOT - ++NumEntries; // DT_PLTREL + Add({DT_JMPREL, Out::RelaPlt}); + Add({DT_PLTRELSZ, Out::RelaPlt->getSize()}); + Add({Config->EMachine == EM_MIPS ? DT_MIPS_PLTGOT : DT_PLTGOT, + Out::GotPlt}); + Add({DT_PLTREL, uint64_t(Config->Rela ? DT_RELA : DT_REL)}); } - ++NumEntries; // DT_SYMTAB - ++NumEntries; // DT_SYMENT - ++NumEntries; // DT_STRTAB - ++NumEntries; // DT_STRSZ + Add({DT_SYMTAB, Out::DynSymTab}); + Add({DT_SYMENT, sizeof(Elf_Sym)}); + Add({DT_STRTAB, Out::DynStrTab}); + Add({DT_STRSZ, Out::DynStrTab->getSize()}); if (Out::GnuHashTab) - ++NumEntries; // DT_GNU_HASH + Add({DT_GNU_HASH, Out::GnuHashTab}); if (Out::HashTab) - ++NumEntries; // DT_HASH + Add({DT_HASH, Out::HashTab}); - if (!Config->RPath.empty()) { - ++NumEntries; // DT_RUNPATH / DT_RPATH - Out::DynStrTab->reserve(Config->RPath); + if (PreInitArraySec) { + Add({DT_PREINIT_ARRAY, PreInitArraySec}); + Add({DT_PREINIT_ARRAYSZ, PreInitArraySec->getSize()}); } - - if (!Config->SoName.empty()) { - ++NumEntries; // DT_SONAME - Out::DynStrTab->reserve(Config->SoName); + if (InitArraySec) { + Add({DT_INIT_ARRAY, InitArraySec}); + Add({DT_INIT_ARRAYSZ, (uintX_t)InitArraySec->getSize()}); } - - if (PreInitArraySec) - NumEntries += 2; - if (InitArraySec) - NumEntries += 2; - if (FiniArraySec) - NumEntries += 2; - - for (const std::unique_ptr> &F : SymTab.getSharedFiles()) { - if (!F->isNeeded()) - continue; - Out::DynStrTab->reserve(F->getSoName()); - ++NumEntries; + if (FiniArraySec) { + Add({DT_FINI_ARRAY, FiniArraySec}); + Add({DT_FINI_ARRAYSZ, (uintX_t)FiniArraySec->getSize()}); } - if (Symbol *S = SymTab.getSymbols().lookup(Config->Init)) - InitSym = S->Body; - if (Symbol *S = SymTab.getSymbols().lookup(Config->Fini)) - FiniSym = S->Body; - if (InitSym) - ++NumEntries; // DT_INIT - if (FiniSym) - ++NumEntries; // DT_FINI + if (SymbolBody *B = Symtab::X->find(Config->Init)) + Add({DT_INIT, B}); + if (SymbolBody *B = Symtab::X->find(Config->Fini)) + Add({DT_FINI, B}); + uint32_t DtFlags = 0; + uint32_t DtFlags1 = 0; if (Config->Bsymbolic) DtFlags |= DF_SYMBOLIC; if (Config->ZNodelete) @@ -626,462 +702,490 @@ template void DynamicSection::finalize() { } if (DtFlags) - ++NumEntries; // DT_FLAGS + Add({DT_FLAGS, DtFlags}); if (DtFlags1) - ++NumEntries; // DT_FLAGS_1 + Add({DT_FLAGS_1, DtFlags1}); if (!Config->Entry.empty()) - ++NumEntries; // DT_DEBUG + Add({DT_DEBUG, (uint64_t)0}); + + bool HasVerNeed = Out::VerNeed->getNeedNum() != 0; + if (HasVerNeed || Out::VerDef) + Add({DT_VERSYM, Out::VerSym}); + if (Out::VerDef) { + Add({DT_VERDEF, Out::VerDef}); + Add({DT_VERDEFNUM, getVerDefNum()}); + } + if (HasVerNeed) { + Add({DT_VERNEED, Out::VerNeed}); + Add({DT_VERNEEDNUM, Out::VerNeed->getNeedNum()}); + } if (Config->EMachine == EM_MIPS) { - ++NumEntries; // DT_MIPS_RLD_VERSION - ++NumEntries; // DT_MIPS_FLAGS - ++NumEntries; // DT_MIPS_BASE_ADDRESS - ++NumEntries; // DT_MIPS_SYMTABNO - ++NumEntries; // DT_MIPS_LOCAL_GOTNO - ++NumEntries; // DT_MIPS_GOTSYM; - ++NumEntries; // DT_PLTGOT + Add({DT_MIPS_RLD_VERSION, 1}); + Add({DT_MIPS_FLAGS, RHF_NOTPOT}); + Add({DT_MIPS_BASE_ADDRESS, Config->ImageBase}); + Add({DT_MIPS_SYMTABNO, Out::DynSymTab->getNumSymbols()}); + Add({DT_MIPS_LOCAL_GOTNO, Out::Got->getMipsLocalEntriesNum()}); + if (const SymbolBody *B = Out::Got->getMipsFirstGlobalEntry()) + Add({DT_MIPS_GOTSYM, B->DynsymIndex}); + else + Add({DT_MIPS_GOTSYM, Out::DynSymTab->getNumSymbols()}); + Add({DT_PLTGOT, Out::Got}); if (Out::MipsRldMap) - ++NumEntries; // DT_MIPS_RLD_MAP + Add({DT_MIPS_RLD_MAP, Out::MipsRldMap}); } - ++NumEntries; // DT_NULL - - Header.sh_size = NumEntries * Header.sh_entsize; + // +1 for DT_NULL + Header.sh_size = (Entries.size() + 1) * Header.sh_entsize; } template void DynamicSection::writeTo(uint8_t *Buf) { auto *P = reinterpret_cast(Buf); - auto WritePtr = [&](int32_t Tag, uint64_t Val) { - P->d_tag = Tag; - P->d_un.d_ptr = Val; - ++P; - }; - - auto WriteVal = [&](int32_t Tag, uint32_t Val) { - P->d_tag = Tag; - P->d_un.d_val = Val; + for (const Entry &E : Entries) { + P->d_tag = E.Tag; + switch (E.Kind) { + case Entry::SecAddr: + P->d_un.d_ptr = E.OutSec->getVA(); + break; + case Entry::SymAddr: + P->d_un.d_ptr = E.Sym->template getVA(); + break; + case Entry::PlainInt: + P->d_un.d_val = E.Val; + break; + } ++P; - }; - - if (Out::RelaDyn->hasRelocs()) { - bool IsRela = Out::RelaDyn->isRela(); - WritePtr(IsRela ? DT_RELA : DT_REL, Out::RelaDyn->getVA()); - WriteVal(IsRela ? DT_RELASZ : DT_RELSZ, Out::RelaDyn->getSize()); - WriteVal(IsRela ? DT_RELAENT : DT_RELENT, - IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel)); } - if (Out::RelaPlt && Out::RelaPlt->hasRelocs()) { - WritePtr(DT_JMPREL, Out::RelaPlt->getVA()); - WriteVal(DT_PLTRELSZ, Out::RelaPlt->getSize()); - // On MIPS, the address of the .got.plt section is stored in - // the DT_MIPS_PLTGOT entry because the DT_PLTGOT entry points to - // the .got section. See "Dynamic Section" in the following document: - // https://sourceware.org/ml/binutils/2008-07/txt00000.txt - WritePtr((Config->EMachine == EM_MIPS) ? DT_MIPS_PLTGOT : DT_PLTGOT, - Out::GotPlt->getVA()); - WriteVal(DT_PLTREL, Out::RelaPlt->isRela() ? DT_RELA : DT_REL); - } - - WritePtr(DT_SYMTAB, Out::DynSymTab->getVA()); - WritePtr(DT_SYMENT, sizeof(Elf_Sym)); - WritePtr(DT_STRTAB, Out::DynStrTab->getVA()); - WriteVal(DT_STRSZ, Out::DynStrTab->getSize()); - if (Out::GnuHashTab) - WritePtr(DT_GNU_HASH, Out::GnuHashTab->getVA()); - if (Out::HashTab) - WritePtr(DT_HASH, Out::HashTab->getVA()); - - // If --enable-new-dtags is set, lld emits DT_RUNPATH - // instead of DT_RPATH. The two tags are functionally - // equivalent except for the following: - // - DT_RUNPATH is searched after LD_LIBRARY_PATH, while - // DT_RPATH is searched before. - // - DT_RUNPATH is used only to search for direct - // dependencies of the object it's contained in, while - // DT_RPATH is used for indirect dependencies as well. - if (!Config->RPath.empty()) - WriteVal(Config->EnableNewDtags ? DT_RUNPATH : DT_RPATH, - Out::DynStrTab->addString(Config->RPath)); - - if (!Config->SoName.empty()) - WriteVal(DT_SONAME, Out::DynStrTab->addString(Config->SoName)); - - auto WriteArray = [&](int32_t T1, int32_t T2, - const OutputSectionBase *Sec) { - if (!Sec) - return; - WritePtr(T1, Sec->getVA()); - WriteVal(T2, Sec->getSize()); - }; - WriteArray(DT_PREINIT_ARRAY, DT_PREINIT_ARRAYSZ, PreInitArraySec); - WriteArray(DT_INIT_ARRAY, DT_INIT_ARRAYSZ, InitArraySec); - WriteArray(DT_FINI_ARRAY, DT_FINI_ARRAYSZ, FiniArraySec); - - for (const std::unique_ptr> &F : SymTab.getSharedFiles()) - if (F->isNeeded()) - WriteVal(DT_NEEDED, Out::DynStrTab->addString(F->getSoName())); +} - if (InitSym) - WritePtr(DT_INIT, getSymVA(*InitSym)); - if (FiniSym) - WritePtr(DT_FINI, getSymVA(*FiniSym)); - if (DtFlags) - WriteVal(DT_FLAGS, DtFlags); - if (DtFlags1) - WriteVal(DT_FLAGS_1, DtFlags1); - if (!Config->Entry.empty()) - WriteVal(DT_DEBUG, 0); +template +EhFrameHeader::EhFrameHeader() + : OutputSectionBase(".eh_frame_hdr", SHT_PROGBITS, SHF_ALLOC) {} + +// .eh_frame_hdr contains a binary search table of pointers to FDEs. +// Each entry of the search table consists of two values, +// the starting PC from where FDEs covers, and the FDE's address. +// It is sorted by PC. +template void EhFrameHeader::writeTo(uint8_t *Buf) { + const endianness E = ELFT::TargetEndianness; - // See "Dynamic Section" in Chapter 5 in the following document - // for detailed description: - // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf - if (Config->EMachine == EM_MIPS) { - WriteVal(DT_MIPS_RLD_VERSION, 1); - WriteVal(DT_MIPS_FLAGS, RHF_NOTPOT); - WritePtr(DT_MIPS_BASE_ADDRESS, Target->getVAStart()); - WriteVal(DT_MIPS_SYMTABNO, Out::DynSymTab->getNumSymbols()); - WriteVal(DT_MIPS_LOCAL_GOTNO, Out::Got->getMipsLocalEntriesNum()); - if (const SymbolBody *B = Out::Got->getMipsFirstGlobalEntry()) - WriteVal(DT_MIPS_GOTSYM, B->DynamicSymbolTableIndex); - else - WriteVal(DT_MIPS_GOTSYM, Out::DynSymTab->getNumSymbols()); - WritePtr(DT_PLTGOT, Out::Got->getVA()); - if (Out::MipsRldMap) - WritePtr(DT_MIPS_RLD_MAP, Out::MipsRldMap->getVA()); + // Sort the FDE list by their PC and uniqueify. Usually there is only + // one FDE for a PC (i.e. function), but if ICF merges two functions + // into one, there can be more than one FDEs pointing to the address. + auto Less = [](const FdeData &A, const FdeData &B) { return A.Pc < B.Pc; }; + std::stable_sort(Fdes.begin(), Fdes.end(), Less); + auto Eq = [](const FdeData &A, const FdeData &B) { return A.Pc == B.Pc; }; + Fdes.erase(std::unique(Fdes.begin(), Fdes.end(), Eq), Fdes.end()); + + Buf[0] = 1; + Buf[1] = DW_EH_PE_pcrel | DW_EH_PE_sdata4; + Buf[2] = DW_EH_PE_udata4; + Buf[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; + write32(Buf + 4, Out::EhFrame->getVA() - this->getVA() - 4); + write32(Buf + 8, Fdes.size()); + Buf += 12; + + uintX_t VA = this->getVA(); + for (FdeData &Fde : Fdes) { + write32(Buf, Fde.Pc - VA); + write32(Buf + 4, Fde.FdeVA - VA); + Buf += 8; } +} + +template void EhFrameHeader::finalize() { + // .eh_frame_hdr has a 12 bytes header followed by an array of FDEs. + this->Header.sh_size = 12 + Out::EhFrame->NumFdes * 8; +} - WriteVal(DT_NULL, 0); +template +void EhFrameHeader::addFde(uint32_t Pc, uint32_t FdeVA) { + Fdes.push_back({Pc, FdeVA}); } template -OutputSection::OutputSection(StringRef Name, uint32_t Type, - uintX_t Flags) - : OutputSectionBase(Name, Type, Flags) {} +OutputSection::OutputSection(StringRef Name, uint32_t Type, uintX_t Flags) + : OutputSectionBase(Name, Type, Flags) { + if (Type == SHT_RELA) + this->Header.sh_entsize = sizeof(Elf_Rela); + else if (Type == SHT_REL) + this->Header.sh_entsize = sizeof(Elf_Rel); +} + +template void OutputSection::finalize() { + uint32_t Type = this->Header.sh_type; + if (Type != SHT_RELA && Type != SHT_REL) + return; + this->Header.sh_link = Out::SymTab->SectionIndex; + // sh_info for SHT_REL[A] sections should contain the section header index of + // the section to which the relocation applies. + InputSectionBase *S = Sections[0]->getRelocatedSection(); + this->Header.sh_info = S->OutSec->SectionIndex; +} template void OutputSection::addSection(InputSectionBase *C) { + assert(C->Live); auto *S = cast>(C); Sections.push_back(S); S->OutSec = this; - uint32_t Align = S->getAlign(); - if (Align > this->Header.sh_addralign) - this->Header.sh_addralign = Align; + this->updateAlignment(S->Alignment); +} - uintX_t Off = this->Header.sh_size; - Off = align(Off, Align); - S->OutSecOff = Off; - Off += S->getSize(); - this->Header.sh_size = Off; +// If an input string is in the form of "foo.N" where N is a number, +// return N. Otherwise, returns 65536, which is one greater than the +// lowest priority. +static int getPriority(StringRef S) { + size_t Pos = S.rfind('.'); + if (Pos == StringRef::npos) + return 65536; + int V; + if (S.substr(Pos + 1).getAsInteger(10, V)) + return 65536; + return V; } -template -typename ELFFile::uintX_t elf2::getSymVA(const SymbolBody &S) { - switch (S.kind()) { - case SymbolBody::DefinedSyntheticKind: { - auto &D = cast>(S); - return D.Section.getVA() + D.Value; - } - case SymbolBody::DefinedRegularKind: { - const auto &DR = cast>(S); - InputSectionBase *SC = DR.Section; - if (!SC) - return DR.Sym.st_value; - - // Symbol offsets for AMDGPU need to be the offset in bytes of the symbol - // from the beginning of the section. - if (Config->EMachine == EM_AMDGPU) - return SC->getOffset(DR.Sym); - if (DR.Sym.getType() == STT_TLS) - return SC->OutSec->getVA() + SC->getOffset(DR.Sym) - - Out::TlsPhdr->p_vaddr; - return SC->OutSec->getVA() + SC->getOffset(DR.Sym); - } - case SymbolBody::DefinedCommonKind: - return Out::Bss->getVA() + cast(S).OffsetInBss; - case SymbolBody::SharedKind: { - auto &SS = cast>(S); - if (SS.NeedsCopy) - return Out::Bss->getVA() + SS.OffsetInBss; - return 0; - } - case SymbolBody::UndefinedElfKind: - case SymbolBody::UndefinedKind: - return 0; - case SymbolBody::LazyKind: - assert(S.isUsedInRegularObj() && "Lazy symbol reached writer"); - return 0; - } - llvm_unreachable("Invalid symbol kind"); -} - -// Returns a VA which a relocatin RI refers to. Used only for local symbols. -// For non-local symbols, use getSymVA instead. -template -typename ELFFile::uintX_t -elf2::getLocalRelTarget(const ObjectFile &File, - const Elf_Rel_Impl &RI, - typename ELFFile::uintX_t Addend) { - typedef typename ELFFile::Elf_Sym Elf_Sym; - typedef typename ELFFile::uintX_t uintX_t; - - // PPC64 has a special relocation representing the TOC base pointer - // that does not have a corresponding symbol. - if (Config->EMachine == EM_PPC64 && RI.getType(false) == R_PPC64_TOC) - return getPPC64TocBase() + Addend; - - const Elf_Sym *Sym = - File.getObj().getRelocationSymbol(&RI, File.getSymbolTable()); - - if (!Sym) - error("Unsupported relocation without symbol"); - - InputSectionBase *Section = File.getSection(*Sym); - - if (Sym->getType() == STT_TLS) - return (Section->OutSec->getVA() + Section->getOffset(*Sym) + Addend) - - Out::TlsPhdr->p_vaddr; - - // According to the ELF spec reference to a local symbol from outside - // the group are not allowed. Unfortunately .eh_frame breaks that rule - // and must be treated specially. For now we just replace the symbol with - // 0. - if (Section == &InputSection::Discarded || !Section->isLive()) - return Addend; - - uintX_t VA = Section->OutSec->getVA(); - if (isa>(Section)) - return VA + Section->getOffset(*Sym) + Addend; - - uintX_t Offset = Sym->st_value; - if (Sym->getType() == STT_SECTION) { - Offset += Addend; - Addend = 0; +// This function is called after we sort input sections +// and scan relocations to setup sections' offsets. +template void OutputSection::assignOffsets() { + uintX_t Off = this->Header.sh_size; + for (InputSection *S : Sections) { + Off = alignTo(Off, S->Alignment); + S->OutSecOff = Off; + Off += S->getSize(); } - return VA + Section->getOffset(Offset) + Addend; + this->Header.sh_size = Off; } -// Returns true if a symbol can be replaced at load-time by a symbol -// with the same name defined in other ELF executable or DSO. -bool elf2::canBePreempted(const SymbolBody *Body, bool NeedsGot) { - if (!Body) - return false; // Body is a local symbol. - if (Body->isShared()) +// Sorts input sections by section name suffixes, so that .foo.N comes +// before .foo.M if N < M. Used to sort .{init,fini}_array.N sections. +// We want to keep the original order if the priorities are the same +// because the compiler keeps the original initialization order in a +// translation unit and we need to respect that. +// For more detail, read the section of the GCC's manual about init_priority. +template void OutputSection::sortInitFini() { + // Sort sections by priority. + typedef std::pair *> Pair; + auto Comp = [](const Pair &A, const Pair &B) { return A.first < B.first; }; + + std::vector V; + for (InputSection *S : Sections) + V.push_back({getPriority(S->getSectionName()), S}); + std::stable_sort(V.begin(), V.end(), Comp); + Sections.clear(); + for (Pair &P : V) + Sections.push_back(P.second); +} + +// Returns true if S matches /Filename.?\.o$/. +static bool isCrtBeginEnd(StringRef S, StringRef Filename) { + if (!S.endswith(".o")) + return false; + S = S.drop_back(2); + if (S.endswith(Filename)) return true; + return !S.empty() && S.drop_back().endswith(Filename); +} - if (Body->isUndefined()) { - if (!Body->isWeak()) - return true; - - // This is an horrible corner case. Ideally we would like to say that any - // undefined symbol can be preempted so that the dynamic linker has a - // chance of finding it at runtime. - // - // The problem is that the code sequence used to test for weak undef - // functions looks like - // if (func) func() - // If the code is -fPIC the first reference is a load from the got and - // everything works. - // If the code is not -fPIC there is no reasonable way to solve it: - // * A relocation writing to the text segment will fail (it is ro). - // * A copy relocation doesn't work for functions. - // * The trick of using a plt entry as the address would fail here since - // the plt entry would have a non zero address. - // Since we cannot do anything better, we just resolve the symbol to 0 and - // don't produce a dynamic relocation. - // - // As an extra hack, assume that if we are producing a shared library the - // user knows what he or she is doing and can handle a dynamic relocation. - return Config->Shared || NeedsGot; - } - if (!Config->Shared) +static bool isCrtbegin(StringRef S) { return isCrtBeginEnd(S, "crtbegin"); } +static bool isCrtend(StringRef S) { return isCrtBeginEnd(S, "crtend"); } + +// .ctors and .dtors are sorted by this priority from highest to lowest. +// +// 1. The section was contained in crtbegin (crtbegin contains +// some sentinel value in its .ctors and .dtors so that the runtime +// can find the beginning of the sections.) +// +// 2. The section has an optional priority value in the form of ".ctors.N" +// or ".dtors.N" where N is a number. Unlike .{init,fini}_array, +// they are compared as string rather than number. +// +// 3. The section is just ".ctors" or ".dtors". +// +// 4. The section was contained in crtend, which contains an end marker. +// +// In an ideal world, we don't need this function because .init_array and +// .ctors are duplicate features (and .init_array is newer.) However, there +// are too many real-world use cases of .ctors, so we had no choice to +// support that with this rather ad-hoc semantics. +template +static bool compCtors(const InputSection *A, + const InputSection *B) { + bool BeginA = isCrtbegin(A->getFile()->getName()); + bool BeginB = isCrtbegin(B->getFile()->getName()); + if (BeginA != BeginB) + return BeginA; + bool EndA = isCrtend(A->getFile()->getName()); + bool EndB = isCrtend(B->getFile()->getName()); + if (EndA != EndB) + return EndB; + StringRef X = A->getSectionName(); + StringRef Y = B->getSectionName(); + assert(X.startswith(".ctors") || X.startswith(".dtors")); + assert(Y.startswith(".ctors") || Y.startswith(".dtors")); + X = X.substr(6); + Y = Y.substr(6); + if (X.empty() && Y.empty()) return false; - return Body->getVisibility() == STV_DEFAULT; + return X < Y; } -template void OutputSection::writeTo(uint8_t *Buf) { - for (InputSection *C : Sections) - C->writeTo(Buf); +// Sorts input sections by the special rules for .ctors and .dtors. +// Unfortunately, the rules are different from the one for .{init,fini}_array. +// Read the comment above. +template void OutputSection::sortCtorsDtors() { + std::stable_sort(Sections.begin(), Sections.end(), compCtors); } -template -EHOutputSection::EHOutputSection(StringRef Name, uint32_t Type, - uintX_t Flags) - : OutputSectionBase(Name, Type, Flags) {} - -template -EHRegion::EHRegion(EHInputSection *S, unsigned Index) - : S(S), Index(Index) {} +static void fill(uint8_t *Buf, size_t Size, ArrayRef A) { + size_t I = 0; + for (; I + A.size() < Size; I += A.size()) + memcpy(Buf + I, A.data(), A.size()); + memcpy(Buf + I, A.data(), Size - I); +} -template StringRef EHRegion::data() const { - ArrayRef SecData = S->getSectionData(); - ArrayRef> Offsets = S->Offsets; - size_t Start = Offsets[Index].first; - size_t End = - Index == Offsets.size() - 1 ? SecData.size() : Offsets[Index + 1].first; - return StringRef((const char *)SecData.data() + Start, End - Start); +template void OutputSection::writeTo(uint8_t *Buf) { + ArrayRef Filler = Script::X->getFiller(this->Name); + if (!Filler.empty()) + fill(Buf, this->getSize(), Filler); + if (Config->Threads) { + parallel_for_each(Sections.begin(), Sections.end(), + [=](InputSection *C) { C->writeTo(Buf); }); + } else { + for (InputSection *C : Sections) + C->writeTo(Buf); + } } template -Cie::Cie(EHInputSection *S, unsigned Index) - : EHRegion(S, Index) {} +EhOutputSection::EhOutputSection() + : OutputSectionBase(".eh_frame", SHT_PROGBITS, SHF_ALLOC) {} + +// Returns the first relocation that points to a region +// between Begin and Begin+Size. +template +static const RelTy *getReloc(IntTy Begin, IntTy Size, ArrayRef &Rels) { + for (auto I = Rels.begin(), E = Rels.end(); I != E; ++I) { + if (I->r_offset < Begin) + continue; + + // Truncate Rels for fast access. That means we expect that the + // relocations are sorted and we are looking up symbols in + // sequential order. It is naturally satisfied for .eh_frame. + Rels = Rels.slice(I - Rels.begin()); + if (I->r_offset < Begin + Size) + return I; + return nullptr; + } + Rels = ArrayRef(); + return nullptr; +} +// Search for an existing CIE record or create a new one. +// CIE records from input object files are uniquified by their contents +// and where their relocations point to. template -template -void EHOutputSection::addSectionAux( - EHInputSection *S, - iterator_range *> Rels) { +template +CieRecord *EhOutputSection::addCie(SectionPiece &Piece, + EhInputSection *Sec, + ArrayRef &Rels) { const endianness E = ELFT::TargetEndianness; + if (read32(Piece.data().data() + 4) != 0) + fatal("CIE expected at beginning of .eh_frame: " + Sec->getSectionName()); - S->OutSec = this; - uint32_t Align = S->getAlign(); - if (Align > this->Header.sh_addralign) - this->Header.sh_addralign = Align; + SymbolBody *Personality = nullptr; + if (const RelTy *Rel = getReloc(Piece.InputOff, Piece.size(), Rels)) + Personality = &Sec->getFile()->getRelocTargetSym(*Rel); - Sections.push_back(S); + // Search for an existing CIE by CIE contents/relocation target pair. + CieRecord *Cie = &CieMap[{Piece.data(), Personality}]; - ArrayRef SecData = S->getSectionData(); - ArrayRef D = SecData; - uintX_t Offset = 0; - auto RelI = Rels.begin(); - auto RelE = Rels.end(); + // If not found, create a new one. + if (Cie->Piece == nullptr) { + Cie->Piece = &Piece; + Cies.push_back(Cie); + } + return Cie; +} - DenseMap OffsetToIndex; - while (!D.empty()) { - unsigned Index = S->Offsets.size(); - S->Offsets.push_back(std::make_pair(Offset, -1)); +// There is one FDE per function. Returns true if a given FDE +// points to a live function. +template +template +bool EhOutputSection::isFdeLive(SectionPiece &Piece, + EhInputSection *Sec, + ArrayRef &Rels) { + const RelTy *Rel = getReloc(Piece.InputOff, Piece.size(), Rels); + if (!Rel) + fatal("FDE doesn't reference another section"); + SymbolBody &B = Sec->getFile()->getRelocTargetSym(*Rel); + auto *D = dyn_cast>(&B); + if (!D || !D->Section) + return false; + InputSectionBase *Target = D->Section->Repl; + return Target && Target->Live; +} - uintX_t Length = readEntryLength(D); - StringRef Entry((const char *)D.data(), Length); +// .eh_frame is a sequence of CIE or FDE records. In general, there +// is one CIE record per input object file which is followed by +// a list of FDEs. This function searches an existing CIE or create a new +// one and associates FDEs to the CIE. +template +template +void EhOutputSection::addSectionAux(EhInputSection *Sec, + ArrayRef Rels) { + const endianness E = ELFT::TargetEndianness; - while (RelI != RelE && RelI->r_offset < Offset) - ++RelI; - uintX_t NextOffset = Offset + Length; - bool HasReloc = RelI != RelE && RelI->r_offset < NextOffset; + DenseMap OffsetToCie; + for (SectionPiece &Piece : Sec->Pieces) { + // The empty record is the end marker. + if (Piece.size() == 4) + return; - uint32_t ID = read32(D.data() + 4); + size_t Offset = Piece.InputOff; + uint32_t ID = read32(Piece.data().data() + 4); if (ID == 0) { - // CIE - Cie C(S, Index); - - StringRef Personality; - if (HasReloc) { - uint32_t SymIndex = RelI->getSymbol(Config->Mips64EL); - SymbolBody &Body = *S->getFile()->getSymbolBody(SymIndex)->repl(); - Personality = Body.getName(); - } - - std::pair CieInfo(Entry, Personality); - auto P = CieMap.insert(std::make_pair(CieInfo, Cies.size())); - if (P.second) { - Cies.push_back(C); - this->Header.sh_size += align(Length, sizeof(uintX_t)); - } - OffsetToIndex[Offset] = P.first->second; - } else { - if (!HasReloc) - error("FDE doesn't reference another section"); - InputSectionBase *Target = S->getRelocTarget(*RelI); - if (Target != &InputSection::Discarded && Target->isLive()) { - uint32_t CieOffset = Offset + 4 - ID; - auto I = OffsetToIndex.find(CieOffset); - if (I == OffsetToIndex.end()) - error("Invalid CIE reference"); - Cies[I->second].Fdes.push_back(EHRegion(S, Index)); - this->Header.sh_size += align(Length, sizeof(uintX_t)); - } + OffsetToCie[Offset] = addCie(Piece, Sec, Rels); + continue; } - Offset = NextOffset; - D = D.slice(Length); + uint32_t CieOffset = Offset + 4 - ID; + CieRecord *Cie = OffsetToCie[CieOffset]; + if (!Cie) + fatal("invalid CIE reference"); + + if (!isFdeLive(Piece, Sec, Rels)) + continue; + Cie->FdePieces.push_back(&Piece); + NumFdes++; } } template -typename EHOutputSection::uintX_t -EHOutputSection::readEntryLength(ArrayRef D) { - const endianness E = ELFT::TargetEndianness; +void EhOutputSection::addSection(InputSectionBase *C) { + auto *Sec = cast>(C); + Sec->OutSec = this; + this->updateAlignment(Sec->Alignment); + Sections.push_back(Sec); + + // .eh_frame is a sequence of CIE or FDE records. This function + // splits it into pieces so that we can call + // SplitInputSection::getSectionPiece on the section. + Sec->split(); + if (Sec->Pieces.empty()) + return; - if (D.size() < 4) - error("Truncated CIE/FDE length"); - uint64_t Len = read32(D.data()); - if (Len < UINT32_MAX) { - if (Len > (UINT32_MAX - 4)) - error("CIE/FIE size is too large"); - if (Len + 4 > D.size()) - error("CIE/FIE ends past the end of the section"); - return Len + 4; + if (const Elf_Shdr *RelSec = Sec->RelocSection) { + ELFFile &Obj = Sec->getFile()->getObj(); + if (RelSec->sh_type == SHT_RELA) + addSectionAux(Sec, Obj.relas(RelSec)); + else + addSectionAux(Sec, Obj.rels(RelSec)); + return; } - - if (D.size() < 12) - error("Truncated CIE/FDE length"); - Len = read64(D.data() + 4); - if (Len > (UINT64_MAX - 12)) - error("CIE/FIE size is too large"); - if (Len + 12 > D.size()) - error("CIE/FIE ends past the end of the section"); - return Len + 12; + addSectionAux(Sec, makeArrayRef(nullptr, nullptr)); } template -void EHOutputSection::addSection(InputSectionBase *C) { - auto *S = cast>(C); - const Elf_Shdr *RelSec = S->RelocSection; - if (!RelSec) - return addSectionAux( - S, make_range((const Elf_Rela *)nullptr, (const Elf_Rela *)nullptr)); - ELFFile &Obj = S->getFile()->getObj(); - if (RelSec->sh_type == SHT_RELA) - return addSectionAux(S, Obj.relas(RelSec)); - return addSectionAux(S, Obj.rels(RelSec)); +static void writeCieFde(uint8_t *Buf, ArrayRef D) { + memcpy(Buf, D.data(), D.size()); + + // Fix the size field. -4 since size does not include the size field itself. + const endianness E = ELFT::TargetEndianness; + write32(Buf, alignTo(D.size(), sizeof(typename ELFT::uint)) - 4); } -template -static typename ELFFile::uintX_t writeAlignedCieOrFde(StringRef Data, - uint8_t *Buf) { - typedef typename ELFFile::uintX_t uintX_t; +template void EhOutputSection::finalize() { + if (this->Header.sh_size) + return; // Already finalized. + + size_t Off = 0; + for (CieRecord *Cie : Cies) { + Cie->Piece->OutputOff = Off; + Off += alignTo(Cie->Piece->size(), sizeof(uintX_t)); + + for (SectionPiece *Fde : Cie->FdePieces) { + Fde->OutputOff = Off; + Off += alignTo(Fde->size(), sizeof(uintX_t)); + } + } + this->Header.sh_size = Off; +} + +template static uint64_t readFdeAddr(uint8_t *Buf, int Size) { const endianness E = ELFT::TargetEndianness; - uint64_t Len = align(Data.size(), sizeof(uintX_t)); - write32(Buf, Len - 4); - memcpy(Buf + 4, Data.data() + 4, Data.size() - 4); - return Len; + switch (Size) { + case DW_EH_PE_udata2: + return read16(Buf); + case DW_EH_PE_udata4: + return read32(Buf); + case DW_EH_PE_udata8: + return read64(Buf); + case DW_EH_PE_absptr: + if (ELFT::Is64Bits) + return read64(Buf); + return read32(Buf); + } + fatal("unknown FDE size encoding"); } -template void EHOutputSection::writeTo(uint8_t *Buf) { +// Returns the VA to which a given FDE (on a mmap'ed buffer) is applied to. +// We need it to create .eh_frame_hdr section. +template +typename ELFT::uint EhOutputSection::getFdePc(uint8_t *Buf, size_t FdeOff, + uint8_t Enc) { + // The starting address to which this FDE applies is + // stored at FDE + 8 byte. + size_t Off = FdeOff + 8; + uint64_t Addr = readFdeAddr(Buf + Off, Enc & 0x7); + if ((Enc & 0x70) == DW_EH_PE_absptr) + return Addr; + if ((Enc & 0x70) == DW_EH_PE_pcrel) + return Addr + this->getVA() + Off; + fatal("unknown FDE size relative encoding"); +} + +template void EhOutputSection::writeTo(uint8_t *Buf) { const endianness E = ELFT::TargetEndianness; - size_t Offset = 0; - for (const Cie &C : Cies) { - size_t CieOffset = Offset; - - uintX_t CIELen = writeAlignedCieOrFde(C.data(), Buf + Offset); - C.S->Offsets[C.Index].second = Offset; - Offset += CIELen; - - for (const EHRegion &F : C.Fdes) { - uintX_t Len = writeAlignedCieOrFde(F.data(), Buf + Offset); - write32(Buf + Offset + 4, Offset + 4 - CieOffset); // Pointer - F.S->Offsets[F.Index].second = Offset; - Offset += Len; + for (CieRecord *Cie : Cies) { + size_t CieOffset = Cie->Piece->OutputOff; + writeCieFde(Buf + CieOffset, Cie->Piece->data()); + + for (SectionPiece *Fde : Cie->FdePieces) { + size_t Off = Fde->OutputOff; + writeCieFde(Buf + Off, Fde->data()); + + // FDE's second word should have the offset to an associated CIE. + // Write it. + write32(Buf + Off + 4, Off + 4 - CieOffset); } } - for (EHInputSection *S : Sections) { - const Elf_Shdr *RelSec = S->RelocSection; - if (!RelSec) - continue; - ELFFile &EObj = S->getFile()->getObj(); - if (RelSec->sh_type == SHT_RELA) - S->relocate(Buf, nullptr, EObj.relas(RelSec)); - else - S->relocate(Buf, nullptr, EObj.rels(RelSec)); + for (EhInputSection *S : Sections) + S->relocate(Buf, nullptr); + + // Construct .eh_frame_hdr. .eh_frame_hdr is a binary search table + // to get a FDE from an address to which FDE is applied. So here + // we obtain two addresses and pass them to EhFrameHdr object. + if (Out::EhFrameHdr) { + for (CieRecord *Cie : Cies) { + uint8_t Enc = getFdeEncoding(Cie->Piece->data()); + for (SectionPiece *Fde : Cie->FdePieces) { + uintX_t Pc = getFdePc(Buf, Fde->OutputOff, Enc); + uintX_t FdeVA = this->getVA() + Fde->OutputOff; + Out::EhFrameHdr->addFde(Pc, FdeVA); + } + } } } template MergeOutputSection::MergeOutputSection(StringRef Name, uint32_t Type, - uintX_t Flags) - : OutputSectionBase(Name, Type, Flags) {} + uintX_t Flags, uintX_t Alignment) + : OutputSectionBase(Name, Type, Flags), + Builder(StringTableBuilder::RAW, Alignment) {} template void MergeOutputSection::writeTo(uint8_t *Buf) { if (shouldTailMerge()) { @@ -1089,58 +1193,32 @@ template void MergeOutputSection::writeTo(uint8_t *Buf) { memcpy(Buf, Data.data(), Data.size()); return; } - for (const std::pair &P : Builder.getMap()) { - StringRef Data = P.first; + for (const std::pair, size_t> &P : Builder.getMap()) { + StringRef Data = P.first.Val; memcpy(Buf + P.second, Data.data(), Data.size()); } } -static size_t findNull(StringRef S, size_t EntSize) { - // Optimize the common case. - if (EntSize == 1) - return S.find(0); - - for (unsigned I = 0, N = S.size(); I != N; I += EntSize) { - const char *B = S.begin() + I; - if (std::all_of(B, B + EntSize, [](char C) { return C == 0; })) - return I; - } - return StringRef::npos; +static StringRef toStringRef(ArrayRef A) { + return {(const char *)A.data(), A.size()}; } template void MergeOutputSection::addSection(InputSectionBase *C) { - auto *S = cast>(C); - S->OutSec = this; - uint32_t Align = S->getAlign(); - if (Align > this->Header.sh_addralign) - this->Header.sh_addralign = Align; - - ArrayRef D = S->getSectionData(); - StringRef Data((const char *)D.data(), D.size()); - uintX_t EntSize = S->getSectionHdr()->sh_entsize; - - if (this->Header.sh_flags & SHF_STRINGS) { - uintX_t Offset = 0; - while (!Data.empty()) { - size_t End = findNull(Data, EntSize); - if (End == StringRef::npos) - error("String is not null terminated"); - StringRef Entry = Data.substr(0, End + EntSize); - uintX_t OutputOffset = Builder.add(Entry); - if (shouldTailMerge()) - OutputOffset = -1; - S->Offsets.push_back(std::make_pair(Offset, OutputOffset)); - uintX_t Size = End + EntSize; - Data = Data.substr(Size); - Offset += Size; - } - } else { - for (unsigned I = 0, N = Data.size(); I != N; I += EntSize) { - StringRef Entry = Data.substr(I, EntSize); - size_t OutputOffset = Builder.add(Entry); - S->Offsets.push_back(std::make_pair(I, OutputOffset)); - } + auto *Sec = cast>(C); + Sec->OutSec = this; + this->updateAlignment(Sec->Alignment); + this->Header.sh_entsize = Sec->getSectionHdr()->sh_entsize; + Sections.push_back(Sec); + + bool IsString = this->Header.sh_flags & SHF_STRINGS; + + for (SectionPiece &Piece : Sec->Pieces) { + if (!Piece.Live) + continue; + uintX_t OutputOffset = Builder.add(toStringRef(Piece.data())); + if (!IsString || !shouldTailMerge()) + Piece.OutputOff = OutputOffset; } } @@ -1159,38 +1237,32 @@ template void MergeOutputSection::finalize() { this->Header.sh_size = Builder.getSize(); } +template void MergeOutputSection::finalizePieces() { + for (MergeInputSection *Sec : Sections) + Sec->finalizePieces(); +} + template StringTableSection::StringTableSection(StringRef Name, bool Dynamic) : OutputSectionBase(Name, SHT_STRTAB, Dynamic ? (uintX_t)SHF_ALLOC : 0), - Dynamic(Dynamic) { - this->Header.sh_addralign = 1; -} + Dynamic(Dynamic) {} -// String tables are created in two phases. First you call reserve() -// to reserve room in the string table, and then call addString() to actually -// add that string. -// -// Why two phases? We want to know the size of the string table as early as -// possible to fix file layout. So we have separated finalize(), which -// determines the size of the section, from writeTo(), which writes the section -// contents to the output buffer. If we merge reserve() with addString(), -// we need a plumbing work for finalize() and writeTo() so that offsets -// we obtained in the former function can be written in the latter. -// This design eliminated that need. -template void StringTableSection::reserve(StringRef S) { - Reserved += S.size() + 1; // +1 for NUL -} - -// Adds a string to the string table. You must call reserve() with the -// same string before calling addString(). -template size_t StringTableSection::addString(StringRef S) { - size_t Pos = Used; +// Adds a string to the string table. If HashIt is true we hash and check for +// duplicates. It is optional because the name of global symbols are already +// uniqued and hashing them again has a big cost for a small value: uniquing +// them with some other string that happens to be the same. +template +unsigned StringTableSection::addString(StringRef S, bool HashIt) { + if (HashIt) { + auto R = StringMap.insert(std::make_pair(S, Size)); + if (!R.second) + return R.first->second; + } + unsigned Ret = Size; + Size += S.size() + 1; Strings.push_back(S); - Used += S.size() + 1; - Reserved -= S.size() + 1; - assert((int64_t)Reserved >= 0); - return Pos; + return Ret; } template void StringTableSection::writeTo(uint8_t *Buf) { @@ -1203,42 +1275,34 @@ template void StringTableSection::writeTo(uint8_t *Buf) { } template -bool elf2::shouldKeepInSymtab(const ObjectFile &File, StringRef SymName, - const typename ELFFile::Elf_Sym &Sym) { - if (Sym.getType() == STT_SECTION) - return false; - - InputSectionBase *Sec = File.getSection(Sym); - // If sym references a section in a discarded group, don't keep it. - if (Sec == &InputSection::Discarded) - return false; - - if (Config->DiscardNone) - return true; - - // In ELF assembly .L symbols are normally discarded by the assembler. - // If the assembler fails to do so, the linker discards them if - // * --discard-locals is used. - // * The symbol is in a SHF_MERGE section, which is normally the reason for - // the assembler keeping the .L symbol. - if (!SymName.startswith(".L") && !SymName.empty()) - return true; +typename ELFT::uint DynamicReloc::getOffset() const { + if (OutputSec) + return OutputSec->getVA() + OffsetInSec; + return InputSec->OutSec->getVA() + InputSec->getOffset(OffsetInSec); +} - if (Config->DiscardLocals) - return false; +template +typename ELFT::uint DynamicReloc::getAddend() const { + if (UseSymVA) + return Sym->getVA(Addend); + return Addend; +} - return !(Sec->getSectionHdr()->sh_flags & SHF_MERGE); +template uint32_t DynamicReloc::getSymIndex() const { + if (Sym && !UseSymVA) + return Sym->DynsymIndex; + return 0; } template SymbolTableSection::SymbolTableSection( - SymbolTable &Table, StringTableSection &StrTabSec) + StringTableSection &StrTabSec) : OutputSectionBase(StrTabSec.isDynamic() ? ".dynsym" : ".symtab", StrTabSec.isDynamic() ? SHT_DYNSYM : SHT_SYMTAB, StrTabSec.isDynamic() ? (uintX_t)SHF_ALLOC : 0), - Table(Table), StrTabSec(StrTabSec) { + StrTabSec(StrTabSec) { this->Header.sh_entsize = sizeof(Elf_Sym); - this->Header.sh_addralign = ELFT::Is64Bits ? 8 : 4; + this->Header.sh_addralign = sizeof(uintX_t); } // Orders symbols according to their positions in the GOT, @@ -1246,10 +1310,25 @@ SymbolTableSection::SymbolTableSection( // See "Global Offset Table" in Chapter 5 in the following document // for detailed description: // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf -static bool sortMipsSymbols(SymbolBody *L, SymbolBody *R) { - if (!L->isInGot() || !R->isInGot()) - return R->isInGot(); - return L->GotIndex < R->GotIndex; +static bool sortMipsSymbols(const std::pair &L, + const std::pair &R) { + // Sort entries related to non-local preemptible symbols by GOT indexes. + // All other entries go to the first part of GOT in arbitrary order. + bool LIsInLocalGot = !L.first->IsInGlobalMipsGot; + bool RIsInLocalGot = !R.first->IsInGlobalMipsGot; + if (LIsInLocalGot || RIsInLocalGot) + return !RIsInLocalGot; + return L.first->GotIndex < R.first->GotIndex; +} + +static uint8_t getSymbolBinding(SymbolBody *Body) { + Symbol *S = Body->symbol(); + uint8_t Visibility = S->Visibility; + if (Visibility != STV_DEFAULT && Visibility != STV_PROTECTED) + return STB_LOCAL; + if (Config->NoGnuUnique && S->Binding == STB_GNU_UNIQUE) + return STB_GLOBAL; + return S->Binding; } template void SymbolTableSection::finalize() { @@ -1260,11 +1339,19 @@ template void SymbolTableSection::finalize() { this->Header.sh_link = StrTabSec.SectionIndex; this->Header.sh_info = NumLocals + 1; + if (Config->Relocatable) { + size_t I = NumLocals; + for (const std::pair &P : Symbols) + P.first->DynsymIndex = ++I; + return; + } + if (!StrTabSec.isDynamic()) { std::stable_sort(Symbols.begin(), Symbols.end(), - [](SymbolBody *L, SymbolBody *R) { - return getSymbolBinding(L) == STB_LOCAL && - getSymbolBinding(R) != STB_LOCAL; + [](const std::pair &L, + const std::pair &R) { + return getSymbolBinding(L.first) == STB_LOCAL && + getSymbolBinding(R.first) != STB_LOCAL; }); return; } @@ -1274,22 +1361,13 @@ template void SymbolTableSection::finalize() { else if (Config->EMachine == EM_MIPS) std::stable_sort(Symbols.begin(), Symbols.end(), sortMipsSymbols); size_t I = 0; - for (SymbolBody *B : Symbols) - B->DynamicSymbolTableIndex = ++I; + for (const std::pair &P : Symbols) + P.first->DynsymIndex = ++I; } template -void SymbolTableSection::addLocalSymbol(StringRef Name) { - StrTabSec.reserve(Name); - ++NumVisible; - ++NumLocals; -} - -template -void SymbolTableSection::addSymbol(SymbolBody *Body) { - StrTabSec.reserve(Body->getName()); - Symbols.push_back(Body); - ++NumVisible; +void SymbolTableSection::addSymbol(SymbolBody *B) { + Symbols.push_back({B, StrTabSec.addString(B->getName(), false)}); } template void SymbolTableSection::writeTo(uint8_t *Buf) { @@ -1307,123 +1385,311 @@ template void SymbolTableSection::writeLocalSymbols(uint8_t *&Buf) { // Iterate over all input object files to copy their local symbols // to the output symbol table pointed by Buf. - for (const std::unique_ptr> &File : Table.getObjectFiles()) { - Elf_Sym_Range Syms = File->getLocalSymbols(); - for (const Elf_Sym &Sym : Syms) { - ErrorOr SymNameOrErr = Sym.getName(File->getStringTable()); - error(SymNameOrErr); - StringRef SymName = *SymNameOrErr; - if (!shouldKeepInSymtab(*File, SymName, Sym)) - continue; - + for (const std::unique_ptr> &File : + Symtab::X->getObjectFiles()) { + for (const std::pair *, size_t> &P : + File->KeptLocalSyms) { + const DefinedRegular &Body = *P.first; + InputSectionBase *Section = Body.Section; auto *ESym = reinterpret_cast(Buf); - uintX_t VA = 0; - if (Sym.st_shndx == SHN_ABS) { + + if (!Section) { ESym->st_shndx = SHN_ABS; - VA = Sym.st_value; + ESym->st_value = Body.Value; } else { - InputSectionBase *Section = File->getSection(Sym); - if (!Section->isLive()) - continue; const OutputSectionBase *OutSec = Section->OutSec; ESym->st_shndx = OutSec->SectionIndex; - VA = Section->getOffset(Sym); - // Symbol offsets for AMDGPU need to be the offset in bytes of the - // symbol from the beginning of the section. - if (Config->EMachine != EM_AMDGPU) - VA += OutSec->getVA(); + ESym->st_value = OutSec->getVA() + Section->getOffset(Body); } - ESym->st_name = StrTabSec.addString(SymName); - ESym->st_size = Sym.st_size; - ESym->setBindingAndType(Sym.getBinding(), Sym.getType()); - ESym->st_value = VA; + ESym->st_name = P.second; + ESym->st_size = Body.template getSize(); + ESym->setBindingAndType(STB_LOCAL, Body.Type); Buf += sizeof(*ESym); } } } -template -static const typename llvm::object::ELFFile::Elf_Sym * -getElfSym(SymbolBody &Body) { - if (auto *EBody = dyn_cast>(&Body)) - return &EBody->Sym; - if (auto *EBody = dyn_cast>(&Body)) - return &EBody->Sym; - return nullptr; -} - template void SymbolTableSection::writeGlobalSymbols(uint8_t *Buf) { // Write the internal symbol table contents to the output symbol table // pointed by Buf. auto *ESym = reinterpret_cast(Buf); - for (SymbolBody *Body : Symbols) { - const OutputSectionBase *OutSec = nullptr; + for (const std::pair &P : Symbols) { + SymbolBody *Body = P.first; + size_t StrOff = P.second; - switch (Body->kind()) { - case SymbolBody::DefinedSyntheticKind: - OutSec = &cast>(Body)->Section; - break; - case SymbolBody::DefinedRegularKind: { - auto *Sym = cast>(Body->repl()); - if (InputSectionBase *Sec = Sym->Section) { - if (!Sec->isLive()) - continue; - OutSec = Sec->OutSec; - } - break; - } - case SymbolBody::DefinedCommonKind: - OutSec = Out::Bss; - break; - case SymbolBody::SharedKind: { - if (cast>(Body)->NeedsCopy) - OutSec = Out::Bss; - break; - } - case SymbolBody::UndefinedElfKind: - case SymbolBody::UndefinedKind: - case SymbolBody::LazyKind: - break; - } - - StringRef Name = Body->getName(); - ESym->st_name = StrTabSec.addString(Name); - - unsigned char Type = STT_NOTYPE; - uintX_t Size = 0; - if (const Elf_Sym *InputSym = getElfSym(*Body)) { - Type = InputSym->getType(); - Size = InputSym->st_size; - } else if (auto *C = dyn_cast(Body)) { - Type = STT_OBJECT; - Size = C->Size; - } + uint8_t Type = Body->Type; + uintX_t Size = Body->getSize(); ESym->setBindingAndType(getSymbolBinding(Body), Type); ESym->st_size = Size; - ESym->setVisibility(Body->getVisibility()); - ESym->st_value = getSymVA(*Body); + ESym->st_name = StrOff; + ESym->setVisibility(Body->symbol()->Visibility); + ESym->st_value = Body->getVA(); - if (OutSec) + if (const OutputSectionBase *OutSec = getOutputSection(Body)) ESym->st_shndx = OutSec->SectionIndex; else if (isa>(Body)) ESym->st_shndx = SHN_ABS; + // On MIPS we need to mark symbol which has a PLT entry and requires pointer + // equality by STO_MIPS_PLT flag. That is necessary to help dynamic linker + // distinguish such symbols and MIPS lazy-binding stubs. + // https://sourceware.org/ml/binutils/2008-07/txt00000.txt + if (Config->EMachine == EM_MIPS && Body->isInPlt() && + Body->NeedsCopyOrPltAddr) + ESym->st_other |= STO_MIPS_PLT; ++ESym; } } template -uint8_t SymbolTableSection::getSymbolBinding(SymbolBody *Body) { - uint8_t Visibility = Body->getVisibility(); - if (Visibility != STV_DEFAULT && Visibility != STV_PROTECTED) - return STB_LOCAL; - if (const Elf_Sym *ESym = getElfSym(*Body)) - return ESym->getBinding(); - if (isa>(Body)) - return STB_LOCAL; - return Body->isWeak() ? STB_WEAK : STB_GLOBAL; +const OutputSectionBase * +SymbolTableSection::getOutputSection(SymbolBody *Sym) { + switch (Sym->kind()) { + case SymbolBody::DefinedSyntheticKind: + return cast>(Sym)->Section; + case SymbolBody::DefinedRegularKind: { + auto &D = cast>(*Sym); + if (D.Section) + return D.Section->OutSec; + break; + } + case SymbolBody::DefinedCommonKind: + return Out::Bss; + case SymbolBody::SharedKind: + if (cast>(Sym)->needsCopy()) + return Out::Bss; + break; + case SymbolBody::UndefinedKind: + case SymbolBody::LazyArchiveKind: + case SymbolBody::LazyObjectKind: + break; + case SymbolBody::DefinedBitcodeKind: + llvm_unreachable("should have been replaced"); + } + return nullptr; +} + +template +VersionDefinitionSection::VersionDefinitionSection() + : OutputSectionBase(".gnu.version_d", SHT_GNU_verdef, SHF_ALLOC) { + this->Header.sh_addralign = sizeof(uint32_t); +} + +static StringRef getFileDefName() { + if (!Config->SoName.empty()) + return Config->SoName; + return Config->OutputFile; +} + +template void VersionDefinitionSection::finalize() { + FileDefNameOff = Out::DynStrTab->addString(getFileDefName()); + for (VersionDefinition &V : Config->VersionDefinitions) + V.NameOff = Out::DynStrTab->addString(V.Name); + + this->Header.sh_size = + (sizeof(Elf_Verdef) + sizeof(Elf_Verdaux)) * getVerDefNum(); + this->Header.sh_link = Out::DynStrTab->SectionIndex; + + // sh_info should be set to the number of definitions. This fact is missed in + // documentation, but confirmed by binutils community: + // https://sourceware.org/ml/binutils/2014-11/msg00355.html + this->Header.sh_info = getVerDefNum(); +} + +template +void VersionDefinitionSection::writeOne(uint8_t *Buf, uint32_t Index, + StringRef Name, size_t NameOff) { + auto *Verdef = reinterpret_cast(Buf); + Verdef->vd_version = 1; + Verdef->vd_cnt = 1; + Verdef->vd_aux = sizeof(Elf_Verdef); + Verdef->vd_next = sizeof(Elf_Verdef) + sizeof(Elf_Verdaux); + Verdef->vd_flags = (Index == 1 ? VER_FLG_BASE : 0); + Verdef->vd_ndx = Index; + Verdef->vd_hash = hashSysv(Name); + + auto *Verdaux = reinterpret_cast(Buf + sizeof(Elf_Verdef)); + Verdaux->vda_name = NameOff; + Verdaux->vda_next = 0; +} + +template +void VersionDefinitionSection::writeTo(uint8_t *Buf) { + writeOne(Buf, 1, getFileDefName(), FileDefNameOff); + + for (VersionDefinition &V : Config->VersionDefinitions) { + Buf += sizeof(Elf_Verdef) + sizeof(Elf_Verdaux); + writeOne(Buf, V.Id, V.Name, V.NameOff); + } + + // Need to terminate the last version definition. + Elf_Verdef *Verdef = reinterpret_cast(Buf); + Verdef->vd_next = 0; +} + +template +VersionTableSection::VersionTableSection() + : OutputSectionBase(".gnu.version", SHT_GNU_versym, SHF_ALLOC) { + this->Header.sh_addralign = sizeof(uint16_t); +} + +template void VersionTableSection::finalize() { + this->Header.sh_size = + sizeof(Elf_Versym) * (Out::DynSymTab->getSymbols().size() + 1); + this->Header.sh_entsize = sizeof(Elf_Versym); + // At the moment of june 2016 GNU docs does not mention that sh_link field + // should be set, but Sun docs do. Also readelf relies on this field. + this->Header.sh_link = Out::DynSymTab->SectionIndex; +} + +template void VersionTableSection::writeTo(uint8_t *Buf) { + auto *OutVersym = reinterpret_cast(Buf) + 1; + for (const std::pair &P : + Out::DynSymTab->getSymbols()) { + OutVersym->vs_index = P.first->symbol()->VersionId; + ++OutVersym; + } +} + +template +VersionNeedSection::VersionNeedSection() + : OutputSectionBase(".gnu.version_r", SHT_GNU_verneed, SHF_ALLOC) { + this->Header.sh_addralign = sizeof(uint32_t); + + // Identifiers in verneed section start at 2 because 0 and 1 are reserved + // for VER_NDX_LOCAL and VER_NDX_GLOBAL. + // First identifiers are reserved by verdef section if it exist. + NextIndex = getVerDefNum() + 1; +} + +template +void VersionNeedSection::addSymbol(SharedSymbol *SS) { + if (!SS->Verdef) { + SS->symbol()->VersionId = VER_NDX_GLOBAL; + return; + } + SharedFile *F = SS->file(); + // If we don't already know that we need an Elf_Verneed for this DSO, prepare + // to create one by adding it to our needed list and creating a dynstr entry + // for the soname. + if (F->VerdefMap.empty()) + Needed.push_back({F, Out::DynStrTab->addString(F->getSoName())}); + typename SharedFile::NeededVer &NV = F->VerdefMap[SS->Verdef]; + // If we don't already know that we need an Elf_Vernaux for this Elf_Verdef, + // prepare to create one by allocating a version identifier and creating a + // dynstr entry for the version name. + if (NV.Index == 0) { + NV.StrTab = Out::DynStrTab->addString( + SS->file()->getStringTable().data() + SS->Verdef->getAux()->vda_name); + NV.Index = NextIndex++; + } + SS->symbol()->VersionId = NV.Index; +} + +template void VersionNeedSection::writeTo(uint8_t *Buf) { + // The Elf_Verneeds need to appear first, followed by the Elf_Vernauxs. + auto *Verneed = reinterpret_cast(Buf); + auto *Vernaux = reinterpret_cast(Verneed + Needed.size()); + + for (std::pair *, size_t> &P : Needed) { + // Create an Elf_Verneed for this DSO. + Verneed->vn_version = 1; + Verneed->vn_cnt = P.first->VerdefMap.size(); + Verneed->vn_file = P.second; + Verneed->vn_aux = + reinterpret_cast(Vernaux) - reinterpret_cast(Verneed); + Verneed->vn_next = sizeof(Elf_Verneed); + ++Verneed; + + // Create the Elf_Vernauxs for this Elf_Verneed. The loop iterates over + // VerdefMap, which will only contain references to needed version + // definitions. Each Elf_Vernaux is based on the information contained in + // the Elf_Verdef in the source DSO. This loop iterates over a std::map of + // pointers, but is deterministic because the pointers refer to Elf_Verdef + // data structures within a single input file. + for (auto &NV : P.first->VerdefMap) { + Vernaux->vna_hash = NV.first->vd_hash; + Vernaux->vna_flags = 0; + Vernaux->vna_other = NV.second.Index; + Vernaux->vna_name = NV.second.StrTab; + Vernaux->vna_next = sizeof(Elf_Vernaux); + ++Vernaux; + } + + Vernaux[-1].vna_next = 0; + } + Verneed[-1].vn_next = 0; +} + +template void VersionNeedSection::finalize() { + this->Header.sh_link = Out::DynStrTab->SectionIndex; + this->Header.sh_info = Needed.size(); + unsigned Size = Needed.size() * sizeof(Elf_Verneed); + for (std::pair *, size_t> &P : Needed) + Size += P.first->VerdefMap.size() * sizeof(Elf_Vernaux); + this->Header.sh_size = Size; +} + +template +BuildIdSection::BuildIdSection(size_t HashSize) + : OutputSectionBase(".note.gnu.build-id", SHT_NOTE, SHF_ALLOC), + HashSize(HashSize) { + // 16 bytes for the note section header. + this->Header.sh_size = 16 + HashSize; +} + +template void BuildIdSection::writeTo(uint8_t *Buf) { + const endianness E = ELFT::TargetEndianness; + write32(Buf, 4); // Name size + write32(Buf + 4, HashSize); // Content size + write32(Buf + 8, NT_GNU_BUILD_ID); // Type + memcpy(Buf + 12, "GNU", 4); // Name string + HashBuf = Buf + 16; +} + +template +void BuildIdFnv1::writeBuildId(ArrayRef> Bufs) { + const endianness E = ELFT::TargetEndianness; + + // 64-bit FNV-1 hash + uint64_t Hash = 0xcbf29ce484222325; + for (ArrayRef Buf : Bufs) { + for (uint8_t B : Buf) { + Hash *= 0x100000001b3; + Hash ^= B; + } + } + write64(this->HashBuf, Hash); +} + +template +void BuildIdMd5::writeBuildId(ArrayRef> Bufs) { + MD5 Hash; + for (ArrayRef Buf : Bufs) + Hash.update(Buf); + MD5::MD5Result Res; + Hash.final(Res); + memcpy(this->HashBuf, Res, 16); +} + +template +void BuildIdSha1::writeBuildId(ArrayRef> Bufs) { + SHA1 Hash; + for (ArrayRef Buf : Bufs) + Hash.update(Buf); + memcpy(this->HashBuf, Hash.final().data(), 20); +} + +template +BuildIdHexstring::BuildIdHexstring() + : BuildIdSection(Config->BuildIdVector.size()) {} + +template +void BuildIdHexstring::writeBuildId(ArrayRef> Bufs) { + memcpy(this->HashBuf, Config->BuildIdVector.data(), + Config->BuildIdVector.size()); } template @@ -1437,7 +1703,7 @@ MipsReginfoOutputSection::MipsReginfoOutputSection() template void MipsReginfoOutputSection::writeTo(uint8_t *Buf) { auto *R = reinterpret_cast(Buf); - R->ri_gp_value = getMipsGpAddr(); + R->ri_gp_value = Out::Got->getVA() + MipsGPOffset; R->ri_gprmask = GprMask; } @@ -1446,15 +1712,136 @@ void MipsReginfoOutputSection::addSection(InputSectionBase *C) { // Copy input object file's .reginfo gprmask to output. auto *S = cast>(C); GprMask |= S->Reginfo->ri_gprmask; + S->OutSec = this; +} + +template +MipsOptionsOutputSection::MipsOptionsOutputSection() + : OutputSectionBase(".MIPS.options", SHT_MIPS_OPTIONS, + SHF_ALLOC | SHF_MIPS_NOSTRIP) { + this->Header.sh_addralign = 8; + this->Header.sh_entsize = 1; + this->Header.sh_size = sizeof(Elf_Mips_Options) + sizeof(Elf_Mips_RegInfo); +} + +template +void MipsOptionsOutputSection::writeTo(uint8_t *Buf) { + auto *Opt = reinterpret_cast(Buf); + Opt->kind = ODK_REGINFO; + Opt->size = this->Header.sh_size; + Opt->section = 0; + Opt->info = 0; + auto *Reg = reinterpret_cast(Buf + sizeof(*Opt)); + Reg->ri_gp_value = Out::Got->getVA() + MipsGPOffset; + Reg->ri_gprmask = GprMask; +} + +template +void MipsOptionsOutputSection::addSection(InputSectionBase *C) { + auto *S = cast>(C); + if (S->Reginfo) + GprMask |= S->Reginfo->ri_gprmask; + S->OutSec = this; +} + +template +std::pair *, bool> +OutputSectionFactory::create(InputSectionBase *C, + StringRef OutsecName) { + SectionKey Key = createKey(C, OutsecName); + OutputSectionBase *&Sec = Map[Key]; + if (Sec) + return {Sec, false}; + + switch (C->SectionKind) { + case InputSectionBase::Regular: + Sec = new OutputSection(Key.Name, Key.Type, Key.Flags); + break; + case InputSectionBase::EHFrame: + return {Out::EhFrame, false}; + case InputSectionBase::Merge: + Sec = new MergeOutputSection(Key.Name, Key.Type, Key.Flags, + Key.Alignment); + break; + case InputSectionBase::MipsReginfo: + Sec = new MipsReginfoOutputSection(); + break; + case InputSectionBase::MipsOptions: + Sec = new MipsOptionsOutputSection(); + break; + } + return {Sec, true}; +} + +template +OutputSectionBase *OutputSectionFactory::lookup(StringRef Name, + uint32_t Type, + uintX_t Flags) { + return Map.lookup({Name, Type, Flags, 0}); +} + +template +SectionKey +OutputSectionFactory::createKey(InputSectionBase *C, + StringRef OutsecName) { + const Elf_Shdr *H = C->getSectionHdr(); + uintX_t Flags = H->sh_flags & ~SHF_GROUP & ~SHF_COMPRESSED; + + // For SHF_MERGE we create different output sections for each alignment. + // This makes each output section simple and keeps a single level mapping from + // input to output. + uintX_t Alignment = 0; + if (isa>(C)) + Alignment = std::max(H->sh_addralign, H->sh_entsize); + + uint32_t Type = H->sh_type; + return SectionKey{OutsecName, Type, Flags, Alignment}; +} + +template +typename lld::elf::SectionKey +DenseMapInfo>::getEmptyKey() { + return SectionKey{DenseMapInfo::getEmptyKey(), 0, 0, 0}; +} + +template +typename lld::elf::SectionKey +DenseMapInfo>::getTombstoneKey() { + return SectionKey{DenseMapInfo::getTombstoneKey(), 0, 0, + 0}; +} + +template +unsigned +DenseMapInfo>::getHashValue(const Key &Val) { + return hash_combine(Val.Name, Val.Type, Val.Flags, Val.Alignment); +} + +template +bool DenseMapInfo>::isEqual(const Key &LHS, + const Key &RHS) { + return DenseMapInfo::isEqual(LHS.Name, RHS.Name) && + LHS.Type == RHS.Type && LHS.Flags == RHS.Flags && + LHS.Alignment == RHS.Alignment; +} + +namespace llvm { +template struct DenseMapInfo>; +template struct DenseMapInfo>; } namespace lld { -namespace elf2 { +namespace elf { template class OutputSectionBase; template class OutputSectionBase; template class OutputSectionBase; template class OutputSectionBase; +template class EhFrameHeader; +template class EhFrameHeader; +template class EhFrameHeader; +template class EhFrameHeader; + template class GotPltSection; template class GotPltSection; template class GotPltSection; @@ -1500,16 +1887,21 @@ template class OutputSection; template class OutputSection; template class OutputSection; -template class EHOutputSection; -template class EHOutputSection; -template class EHOutputSection; -template class EHOutputSection; +template class EhOutputSection; +template class EhOutputSection; +template class EhOutputSection; +template class EhOutputSection; template class MipsReginfoOutputSection; template class MipsReginfoOutputSection; template class MipsReginfoOutputSection; template class MipsReginfoOutputSection; +template class MipsOptionsOutputSection; +template class MipsOptionsOutputSection; +template class MipsOptionsOutputSection; +template class MipsOptionsOutputSection; + template class MergeOutputSection; template class MergeOutputSection; template class MergeOutputSection; @@ -1525,39 +1917,49 @@ template class SymbolTableSection; template class SymbolTableSection; template class SymbolTableSection; -template ELFFile::uintX_t getSymVA(const SymbolBody &); -template ELFFile::uintX_t getSymVA(const SymbolBody &); -template ELFFile::uintX_t getSymVA(const SymbolBody &); -template ELFFile::uintX_t getSymVA(const SymbolBody &); - -template ELFFile::uintX_t -getLocalRelTarget(const ObjectFile &, - const ELFFile::Elf_Rel &, - ELFFile::uintX_t Addend); -template ELFFile::uintX_t -getLocalRelTarget(const ObjectFile &, - const ELFFile::Elf_Rel &, - ELFFile::uintX_t Addend); -template ELFFile::uintX_t -getLocalRelTarget(const ObjectFile &, - const ELFFile::Elf_Rel &, - ELFFile::uintX_t Addend); -template ELFFile::uintX_t -getLocalRelTarget(const ObjectFile &, - const ELFFile::Elf_Rel &, - ELFFile::uintX_t Addend); - -template bool shouldKeepInSymtab(const ObjectFile &, - StringRef, - const ELFFile::Elf_Sym &); -template bool shouldKeepInSymtab(const ObjectFile &, - StringRef, - const ELFFile::Elf_Sym &); -template bool shouldKeepInSymtab(const ObjectFile &, - StringRef, - const ELFFile::Elf_Sym &); -template bool shouldKeepInSymtab(const ObjectFile &, - StringRef, - const ELFFile::Elf_Sym &); +template class VersionTableSection; +template class VersionTableSection; +template class VersionTableSection; +template class VersionTableSection; + +template class VersionNeedSection; +template class VersionNeedSection; +template class VersionNeedSection; +template class VersionNeedSection; + +template class VersionDefinitionSection; +template class VersionDefinitionSection; +template class VersionDefinitionSection; +template class VersionDefinitionSection; + +template class BuildIdSection; +template class BuildIdSection; +template class BuildIdSection; +template class BuildIdSection; + +template class BuildIdFnv1; +template class BuildIdFnv1; +template class BuildIdFnv1; +template class BuildIdFnv1; + +template class BuildIdMd5; +template class BuildIdMd5; +template class BuildIdMd5; +template class BuildIdMd5; + +template class BuildIdSha1; +template class BuildIdSha1; +template class BuildIdSha1; +template class BuildIdSha1; + +template class BuildIdHexstring; +template class BuildIdHexstring; +template class BuildIdHexstring; +template class BuildIdHexstring; + +template class OutputSectionFactory; +template class OutputSectionFactory; +template class OutputSectionFactory; +template class OutputSectionFactory; } } -- cgit v1.2.3