forked from OSchip/llvm-project
704 lines
24 KiB
C++
704 lines
24 KiB
C++
//===- OutputSections.cpp -------------------------------------------------===//
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//
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// The LLVM Linker
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "OutputSections.h"
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#include "Config.h"
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#include "SymbolTable.h"
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#include "Target.h"
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using namespace llvm;
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using namespace llvm::object;
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using namespace llvm::support::endian;
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using namespace llvm::ELF;
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using namespace lld;
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using namespace lld::elf2;
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template <bool Is64Bits>
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OutputSectionBase<Is64Bits>::OutputSectionBase(StringRef Name, uint32_t sh_type,
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uintX_t sh_flags)
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: Name(Name) {
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memset(&Header, 0, sizeof(HeaderT));
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Header.sh_type = sh_type;
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Header.sh_flags = sh_flags;
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}
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template <class ELFT>
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GotSection<ELFT>::GotSection(const OutputSection<ELFT> &BssSec)
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: OutputSectionBase<ELFT::Is64Bits>(".got", llvm::ELF::SHT_PROGBITS,
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llvm::ELF::SHF_ALLOC |
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llvm::ELF::SHF_WRITE),
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BssSec(BssSec) {
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this->Header.sh_addralign = this->getAddrSize();
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}
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template <class ELFT> void GotSection<ELFT>::addEntry(SymbolBody *Sym) {
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Sym->setGotIndex(Entries.size());
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Entries.push_back(Sym);
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}
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template <class ELFT>
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typename GotSection<ELFT>::uintX_t
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GotSection<ELFT>::getEntryAddr(const SymbolBody &B) const {
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return this->getVA() + B.getGotIndex() * this->getAddrSize();
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}
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template <class ELFT> void GotSection<ELFT>::writeTo(uint8_t *Buf) {
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for (const SymbolBody *B : Entries) {
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if (canBePreempted(B))
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continue; // The dynamic linker will take care of it.
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uintX_t VA = getSymVA(*B, BssSec);
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write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Buf, VA);
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Buf += sizeof(uintX_t);
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}
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}
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template <class ELFT>
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PltSection<ELFT>::PltSection(const GotSection<ELFT> &GotSec)
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: OutputSectionBase<ELFT::Is64Bits>(".plt", llvm::ELF::SHT_PROGBITS,
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llvm::ELF::SHF_ALLOC |
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llvm::ELF::SHF_EXECINSTR),
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GotSec(GotSec) {
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this->Header.sh_addralign = 16;
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}
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template <class ELFT> void PltSection<ELFT>::writeTo(uint8_t *Buf) {
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uintptr_t Start = reinterpret_cast<uintptr_t>(Buf);
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for (const SymbolBody *E : Entries) {
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uint64_t GotEntryAddr = GotSec.getEntryAddr(*E);
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uintptr_t InstPos = reinterpret_cast<uintptr_t>(Buf);
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uint64_t PltEntryAddr = (InstPos - Start) + this->getVA();
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Target->writePltEntry(Buf, GotEntryAddr, PltEntryAddr);
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Buf += 8;
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}
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}
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template <class ELFT> void PltSection<ELFT>::addEntry(SymbolBody *Sym) {
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Sym->setPltIndex(Entries.size());
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Entries.push_back(Sym);
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}
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template <class ELFT>
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typename PltSection<ELFT>::uintX_t
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PltSection<ELFT>::getEntryAddr(const SymbolBody &B) const {
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return this->getVA() + B.getPltIndex() * EntrySize;
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}
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template <class ELFT>
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RelocationSection<ELFT>::RelocationSection(SymbolTableSection<ELFT> &DynSymSec,
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const GotSection<ELFT> &GotSec,
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const OutputSection<ELFT> &BssSec,
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bool IsRela)
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: OutputSectionBase<ELFT::Is64Bits>(IsRela ? ".rela.dyn" : ".rel.dyn",
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IsRela ? llvm::ELF::SHT_RELA
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: llvm::ELF::SHT_REL,
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llvm::ELF::SHF_ALLOC),
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DynSymSec(DynSymSec), GotSec(GotSec), BssSec(BssSec), IsRela(IsRela) {
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this->Header.sh_entsize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel);
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this->Header.sh_addralign = ELFT::Is64Bits ? 8 : 4;
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}
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template <class ELFT> void RelocationSection<ELFT>::writeTo(uint8_t *Buf) {
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const unsigned EntrySize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel);
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bool IsMips64EL = Relocs[0].C.getFile()->getObj().isMips64EL();
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for (const DynamicReloc<ELFT> &Rel : Relocs) {
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auto *P = reinterpret_cast<Elf_Rel *>(Buf);
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Buf += EntrySize;
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const InputSection<ELFT> &C = Rel.C;
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const Elf_Rel &RI = Rel.RI;
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OutputSection<ELFT> *Out = C.getOutputSection();
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uint32_t SymIndex = RI.getSymbol(IsMips64EL);
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const ObjectFile<ELFT> &File = *C.getFile();
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const SymbolBody *Body = File.getSymbolBody(SymIndex);
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const ELFFile<ELFT> &Obj = File.getObj();
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uint32_t Type = RI.getType(IsMips64EL);
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bool CanBePreempted = canBePreempted(Body);
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uintX_t Addend = 0;
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if (!CanBePreempted) {
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if (IsRela) {
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if (Body)
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Addend += getSymVA(cast<ELFSymbolBody<ELFT>>(*Body), BssSec);
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else
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Addend += getLocalSymVA(
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Obj.getRelocationSymbol(&RI, File.getSymbolTable()), File);
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}
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P->setSymbolAndType(0, Target->getRelativeReloc(), IsMips64EL);
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}
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if (Body && Target->relocNeedsGot(Type, *Body)) {
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P->r_offset = GotSec.getEntryAddr(*Body);
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if (CanBePreempted)
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P->setSymbolAndType(Body->getDynamicSymbolTableIndex(),
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Target->getGotReloc(), IsMips64EL);
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} else {
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if (IsRela)
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Addend += static_cast<const Elf_Rela &>(RI).r_addend;
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P->r_offset = RI.r_offset + C.getOutputSectionOff() + Out->getVA();
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if (CanBePreempted)
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P->setSymbolAndType(Body->getDynamicSymbolTableIndex(), Type,
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IsMips64EL);
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}
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if (IsRela)
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static_cast<Elf_Rela *>(P)->r_addend = Addend;
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}
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}
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template <class ELFT> void RelocationSection<ELFT>::finalize() {
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this->Header.sh_link = DynSymSec.getSectionIndex();
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this->Header.sh_size = Relocs.size() * this->Header.sh_entsize;
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}
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template <bool Is64Bits>
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InterpSection<Is64Bits>::InterpSection()
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: OutputSectionBase<Is64Bits>(".interp", llvm::ELF::SHT_PROGBITS,
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llvm::ELF::SHF_ALLOC) {
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this->Header.sh_size = Config->DynamicLinker.size() + 1;
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this->Header.sh_addralign = 1;
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}
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template <bool Is64Bits>
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template <endianness E>
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void OutputSectionBase<Is64Bits>::writeHeaderTo(
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typename ELFFile<ELFType<E, Is64Bits>>::Elf_Shdr *SHdr) {
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SHdr->sh_name = Header.sh_name;
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SHdr->sh_type = Header.sh_type;
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SHdr->sh_flags = Header.sh_flags;
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SHdr->sh_addr = Header.sh_addr;
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SHdr->sh_offset = Header.sh_offset;
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SHdr->sh_size = Header.sh_size;
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SHdr->sh_link = Header.sh_link;
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SHdr->sh_info = Header.sh_info;
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SHdr->sh_addralign = Header.sh_addralign;
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SHdr->sh_entsize = Header.sh_entsize;
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}
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template <bool Is64Bits> void InterpSection<Is64Bits>::writeTo(uint8_t *Buf) {
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memcpy(Buf, Config->DynamicLinker.data(), Config->DynamicLinker.size());
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}
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template <class ELFT>
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HashTableSection<ELFT>::HashTableSection(SymbolTableSection<ELFT> &DynSymSec)
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: OutputSectionBase<ELFT::Is64Bits>(".hash", llvm::ELF::SHT_HASH,
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llvm::ELF::SHF_ALLOC),
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DynSymSec(DynSymSec) {
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this->Header.sh_entsize = sizeof(Elf_Word);
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this->Header.sh_addralign = sizeof(Elf_Word);
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}
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template <class ELFT> void HashTableSection<ELFT>::addSymbol(SymbolBody *S) {
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StringRef Name = S->getName();
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DynSymSec.addSymbol(Name);
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Hashes.push_back(hash(Name));
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S->setDynamicSymbolTableIndex(Hashes.size());
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}
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template <class ELFT>
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DynamicSection<ELFT>::DynamicSection(SymbolTable &SymTab,
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HashTableSection<ELFT> &HashSec,
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RelocationSection<ELFT> &RelaDynSec,
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const OutputSection<ELFT> &BssSec)
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: OutputSectionBase<ELFT::Is64Bits>(".dynamic", llvm::ELF::SHT_DYNAMIC,
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llvm::ELF::SHF_ALLOC |
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llvm::ELF::SHF_WRITE),
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HashSec(HashSec), DynSymSec(HashSec.getDynSymSec()),
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DynStrSec(DynSymSec.getStrTabSec()), RelaDynSec(RelaDynSec),
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BssSec(BssSec), SymTab(SymTab) {
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typename Base::HeaderT &Header = this->Header;
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Header.sh_addralign = ELFT::Is64Bits ? 8 : 4;
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Header.sh_entsize = ELFT::Is64Bits ? 16 : 8;
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}
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template <class ELFT> void DynamicSection<ELFT>::finalize() {
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if (this->Header.sh_size)
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return; // Already finalized.
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typename Base::HeaderT &Header = this->Header;
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Header.sh_link = DynStrSec.getSectionIndex();
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unsigned NumEntries = 0;
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if (RelaDynSec.hasRelocs()) {
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++NumEntries; // DT_RELA / DT_REL
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++NumEntries; // DT_RELASZ / DT_RELSZ
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++NumEntries; // DT_RELAENT / DT_RELENT
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}
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++NumEntries; // DT_SYMTAB
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++NumEntries; // DT_SYMENT
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++NumEntries; // DT_STRTAB
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++NumEntries; // DT_STRSZ
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++NumEntries; // DT_HASH
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if (!Config->RPath.empty()) {
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++NumEntries; // DT_RUNPATH / DT_RPATH
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DynStrSec.add(Config->RPath);
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}
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if (!Config->SoName.empty()) {
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++NumEntries; // DT_SONAME
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DynStrSec.add(Config->SoName);
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}
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if (PreInitArraySec)
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NumEntries += 2;
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if (InitArraySec)
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NumEntries += 2;
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if (FiniArraySec)
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NumEntries += 2;
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const std::vector<std::unique_ptr<SharedFileBase>> &SharedFiles =
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SymTab.getSharedFiles();
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for (const std::unique_ptr<SharedFileBase> &File : SharedFiles)
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DynStrSec.add(File->getSoName());
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NumEntries += SharedFiles.size();
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if (Symbol *S = SymTab.getSymbols().lookup(Config->Init))
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InitSym = dyn_cast<ELFSymbolBody<ELFT>>(S->Body);
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if (Symbol *S = SymTab.getSymbols().lookup(Config->Fini))
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FiniSym = dyn_cast<ELFSymbolBody<ELFT>>(S->Body);
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if (InitSym)
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++NumEntries; // DT_INIT
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if (FiniSym)
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++NumEntries; // DT_FINI
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++NumEntries; // DT_NULL
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Header.sh_size = NumEntries * Header.sh_entsize;
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}
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template <class ELFT> void DynamicSection<ELFT>::writeTo(uint8_t *Buf) {
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auto *P = reinterpret_cast<Elf_Dyn *>(Buf);
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auto WritePtr = [&](int32_t Tag, uint64_t Val) {
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P->d_tag = Tag;
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P->d_un.d_ptr = Val;
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++P;
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};
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auto WriteVal = [&](int32_t Tag, uint32_t Val) {
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P->d_tag = Tag;
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P->d_un.d_val = Val;
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++P;
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};
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if (RelaDynSec.hasRelocs()) {
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bool IsRela = RelaDynSec.isRela();
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WritePtr(IsRela ? DT_RELA : DT_REL, RelaDynSec.getVA());
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WriteVal(IsRela ? DT_RELASZ : DT_RELSZ, RelaDynSec.getSize());
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WriteVal(IsRela ? DT_RELAENT : DT_RELENT,
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IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel));
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}
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WritePtr(DT_SYMTAB, DynSymSec.getVA());
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WritePtr(DT_SYMENT, sizeof(Elf_Sym));
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WritePtr(DT_STRTAB, DynStrSec.getVA());
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WriteVal(DT_STRSZ, DynStrSec.data().size());
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WritePtr(DT_HASH, HashSec.getVA());
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if (!Config->RPath.empty())
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// If --enable-new-dtags is set lld emits DT_RUNPATH
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// instead of DT_RPATH. The two tags are functionally
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// equivalent except for the following:
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// - DT_RUNPATH is searched after LD_LIBRARY_PATH, while
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// DT_RPATH is searched before.
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// - DT_RUNPATH is used only to search for direct
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// dependencies of the object it's contained in, while
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// DT_RPATH is used for indirect dependencies as well.
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WriteVal(Config->EnableNewDtags ? DT_RUNPATH : DT_RPATH,
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DynStrSec.getFileOff(Config->RPath));
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if (!Config->SoName.empty())
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WriteVal(DT_SONAME, DynStrSec.getFileOff(Config->SoName));
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auto WriteArray = [&](int32_t T1, int32_t T2,
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const OutputSection<ELFT> *Sec) {
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if (!Sec)
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return;
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WritePtr(T1, Sec->getVA());
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WriteVal(T2, Sec->getSize());
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};
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WriteArray(DT_PREINIT_ARRAY, DT_PREINIT_ARRAYSZ, PreInitArraySec);
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WriteArray(DT_INIT_ARRAY, DT_INIT_ARRAYSZ, InitArraySec);
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WriteArray(DT_FINI_ARRAY, DT_FINI_ARRAYSZ, FiniArraySec);
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const std::vector<std::unique_ptr<SharedFileBase>> &SharedFiles =
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SymTab.getSharedFiles();
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for (const std::unique_ptr<SharedFileBase> &File : SharedFiles)
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WriteVal(DT_NEEDED, DynStrSec.getFileOff(File->getSoName()));
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if (InitSym)
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WritePtr(DT_INIT, getSymVA(*InitSym, BssSec));
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if (FiniSym)
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WritePtr(DT_FINI, getSymVA(*FiniSym, BssSec));
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WriteVal(DT_NULL, 0);
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}
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template <class ELFT>
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OutputSection<ELFT>::OutputSection(const PltSection<ELFT> &PltSec,
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const GotSection<ELFT> &GotSec,
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const OutputSection<ELFT> &BssSec,
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StringRef Name, uint32_t sh_type,
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uintX_t sh_flags)
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: OutputSectionBase<ELFT::Is64Bits>(Name, sh_type, sh_flags),
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PltSec(PltSec), GotSec(GotSec), BssSec(BssSec) {}
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template <class ELFT>
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void OutputSection<ELFT>::addSection(InputSection<ELFT> *C) {
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Sections.push_back(C);
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C->setOutputSection(this);
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uint32_t Align = C->getAlign();
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if (Align > this->Header.sh_addralign)
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this->Header.sh_addralign = Align;
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uintX_t Off = this->Header.sh_size;
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Off = RoundUpToAlignment(Off, Align);
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C->setOutputSectionOff(Off);
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Off += C->getSize();
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this->Header.sh_size = Off;
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}
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template <class ELFT>
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typename ELFFile<ELFT>::uintX_t
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lld::elf2::getSymVA(const SymbolBody &S, const OutputSection<ELFT> &BssSec) {
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switch (S.kind()) {
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case SymbolBody::DefinedSyntheticKind: {
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auto &D = cast<DefinedSynthetic<ELFT>>(S);
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return D.Section.getVA() + D.Sym.st_value;
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}
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case SymbolBody::DefinedAbsoluteKind:
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return cast<DefinedAbsolute<ELFT>>(S).Sym.st_value;
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case SymbolBody::DefinedRegularKind: {
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const auto &DR = cast<DefinedRegular<ELFT>>(S);
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const InputSection<ELFT> *SC = &DR.Section;
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OutputSection<ELFT> *OS = SC->getOutputSection();
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return OS->getVA() + SC->getOutputSectionOff() + DR.Sym.st_value;
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}
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case SymbolBody::DefinedCommonKind:
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return BssSec.getVA() + cast<DefinedCommon<ELFT>>(S).OffsetInBSS;
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case SymbolBody::SharedKind:
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case SymbolBody::UndefinedKind:
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return 0;
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case SymbolBody::LazyKind:
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assert(S.isUsedInRegularObj() && "Lazy symbol reached writer");
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return 0;
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}
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}
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template <class ELFT>
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typename ELFFile<ELFT>::uintX_t
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lld::elf2::getLocalSymVA(const typename ELFFile<ELFT>::Elf_Sym *Sym,
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const ObjectFile<ELFT> &File) {
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uint32_t SecIndex = Sym->st_shndx;
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if (SecIndex == SHN_XINDEX)
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SecIndex = File.getObj().getExtendedSymbolTableIndex(
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Sym, File.getSymbolTable(), File.getSymbolTableShndx());
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ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
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InputSection<ELFT> *Section = Sections[SecIndex];
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OutputSection<ELFT> *Out = Section->getOutputSection();
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return Out->getVA() + Section->getOutputSectionOff() + Sym->st_value;
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}
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bool lld::elf2::canBePreempted(const SymbolBody *Body) {
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if (!Body)
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return false;
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if (Body->isShared() || Body->isUndefined())
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return true;
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if (!Config->Shared)
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return false;
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return Body->getMostConstrainingVisibility() == STV_DEFAULT;
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}
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template <class ELFT> void OutputSection<ELFT>::writeTo(uint8_t *Buf) {
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for (InputSection<ELFT> *C : Sections)
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C->writeTo(Buf, BssSec, PltSec, GotSec);
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}
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template <bool Is64Bits>
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StringTableSection<Is64Bits>::StringTableSection(bool Dynamic)
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: OutputSectionBase<Is64Bits>(Dynamic ? ".dynstr" : ".strtab",
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llvm::ELF::SHT_STRTAB,
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Dynamic ? (uintX_t)llvm::ELF::SHF_ALLOC : 0),
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Dynamic(Dynamic) {
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this->Header.sh_addralign = 1;
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}
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template <bool Is64Bits>
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void StringTableSection<Is64Bits>::writeTo(uint8_t *Buf) {
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StringRef Data = StrTabBuilder.data();
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memcpy(Buf, Data.data(), Data.size());
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}
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template <class ELFT> bool lld::elf2::includeInSymtab(const SymbolBody &B) {
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if (!B.isUsedInRegularObj())
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return false;
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// Don't include synthetic symbols like __init_array_start in every output.
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if (auto *U = dyn_cast<DefinedAbsolute<ELFT>>(&B))
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if (&U->Sym == &DefinedAbsolute<ELFT>::IgnoreUndef)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool lld::elf2::includeInDynamicSymtab(const SymbolBody &B) {
|
|
uint8_t V = B.getMostConstrainingVisibility();
|
|
if (V != STV_DEFAULT && V != STV_PROTECTED)
|
|
return false;
|
|
|
|
if (Config->ExportDynamic || Config->Shared)
|
|
return true;
|
|
return B.isUsedInDynamicReloc();
|
|
}
|
|
|
|
template <class ELFT>
|
|
bool lld::elf2::shouldKeepInSymtab(StringRef SymName,
|
|
const typename ELFFile<ELFT>::Elf_Sym &Sym) {
|
|
if (Sym.getType() == STT_SECTION)
|
|
return false;
|
|
|
|
if (Config->DiscardNone)
|
|
return true;
|
|
|
|
// ELF defines dynamic locals as symbols which name starts with ".L".
|
|
return !(Config->DiscardLocals && SymName.startswith(".L"));
|
|
}
|
|
|
|
template <class ELFT>
|
|
SymbolTableSection<ELFT>::SymbolTableSection(
|
|
SymbolTable &Table, StringTableSection<ELFT::Is64Bits> &StrTabSec,
|
|
const OutputSection<ELFT> &BssSec)
|
|
: OutputSectionBase<ELFT::Is64Bits>(
|
|
StrTabSec.isDynamic() ? ".dynsym" : ".symtab",
|
|
StrTabSec.isDynamic() ? llvm::ELF::SHT_DYNSYM : llvm::ELF::SHT_SYMTAB,
|
|
StrTabSec.isDynamic() ? (uintX_t)llvm::ELF::SHF_ALLOC : 0),
|
|
Table(Table), StrTabSec(StrTabSec), BssSec(BssSec) {
|
|
typedef OutputSectionBase<ELFT::Is64Bits> Base;
|
|
typename Base::HeaderT &Header = this->Header;
|
|
|
|
Header.sh_entsize = sizeof(Elf_Sym);
|
|
Header.sh_addralign = ELFT::Is64Bits ? 8 : 4;
|
|
}
|
|
|
|
template <class ELFT> void SymbolTableSection<ELFT>::writeTo(uint8_t *Buf) {
|
|
Buf += sizeof(Elf_Sym);
|
|
|
|
// All symbols with STB_LOCAL binding precede the weak and global symbols.
|
|
// .dynsym only contains global symbols.
|
|
if (!Config->DiscardAll && !StrTabSec.isDynamic())
|
|
writeLocalSymbols(Buf);
|
|
|
|
writeGlobalSymbols(Buf);
|
|
}
|
|
|
|
template <class ELFT>
|
|
void SymbolTableSection<ELFT>::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<ObjectFileBase> &FileB : Table.getObjectFiles()) {
|
|
auto &File = cast<ObjectFile<ELFT>>(*FileB);
|
|
Elf_Sym_Range Syms = File.getLocalSymbols();
|
|
for (const Elf_Sym &Sym : Syms) {
|
|
ErrorOr<StringRef> SymName = Sym.getName(File.getStringTable());
|
|
if (SymName && !shouldKeepInSymtab<ELFT>(*SymName, Sym))
|
|
continue;
|
|
auto *ESym = reinterpret_cast<Elf_Sym *>(Buf);
|
|
Buf += sizeof(*ESym);
|
|
ESym->st_name = (SymName) ? StrTabSec.getFileOff(*SymName) : 0;
|
|
ESym->st_size = Sym.st_size;
|
|
ESym->setBindingAndType(Sym.getBinding(), Sym.getType());
|
|
uint32_t SecIndex = Sym.st_shndx;
|
|
uintX_t VA = Sym.st_value;
|
|
if (SecIndex == SHN_ABS) {
|
|
ESym->st_shndx = SHN_ABS;
|
|
} else {
|
|
if (SecIndex == SHN_XINDEX)
|
|
SecIndex = File.getObj().getExtendedSymbolTableIndex(
|
|
&Sym, File.getSymbolTable(), File.getSymbolTableShndx());
|
|
ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
|
|
const InputSection<ELFT> *Section = Sections[SecIndex];
|
|
const OutputSection<ELFT> *Out = Section->getOutputSection();
|
|
ESym->st_shndx = Out->getSectionIndex();
|
|
VA += Out->getVA() + Section->getOutputSectionOff();
|
|
}
|
|
ESym->st_value = VA;
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class ELFT>
|
|
void SymbolTableSection<ELFT>::writeGlobalSymbols(uint8_t *&Buf) {
|
|
// Write the internal symbol table contents to the output symbol table
|
|
// pointed by Buf.
|
|
uint8_t *Start = Buf;
|
|
for (const std::pair<StringRef, Symbol *> &P : Table.getSymbols()) {
|
|
StringRef Name = P.first;
|
|
Symbol *Sym = P.second;
|
|
SymbolBody *Body = Sym->Body;
|
|
if (!includeInSymtab<ELFT>(*Body))
|
|
continue;
|
|
if (StrTabSec.isDynamic() && !includeInDynamicSymtab(*Body))
|
|
continue;
|
|
|
|
auto *ESym = reinterpret_cast<Elf_Sym *>(Buf);
|
|
Buf += sizeof(*ESym);
|
|
|
|
ESym->st_name = StrTabSec.getFileOff(Name);
|
|
|
|
const OutputSection<ELFT> *Out = nullptr;
|
|
const InputSection<ELFT> *Section = nullptr;
|
|
|
|
switch (Body->kind()) {
|
|
case SymbolBody::DefinedSyntheticKind:
|
|
Out = &cast<DefinedSynthetic<ELFT>>(Body)->Section;
|
|
break;
|
|
case SymbolBody::DefinedRegularKind:
|
|
Section = &cast<DefinedRegular<ELFT>>(Body)->Section;
|
|
break;
|
|
case SymbolBody::DefinedCommonKind:
|
|
Out = &BssSec;
|
|
break;
|
|
case SymbolBody::UndefinedKind:
|
|
case SymbolBody::DefinedAbsoluteKind:
|
|
case SymbolBody::SharedKind:
|
|
case SymbolBody::LazyKind:
|
|
break;
|
|
}
|
|
|
|
unsigned char Binding = Body->isWeak() ? STB_WEAK : STB_GLOBAL;
|
|
unsigned char Type = STT_NOTYPE;
|
|
uintX_t Size = 0;
|
|
if (const auto *EBody = dyn_cast<ELFSymbolBody<ELFT>>(Body)) {
|
|
const Elf_Sym &InputSym = EBody->Sym;
|
|
Binding = InputSym.getBinding();
|
|
Type = InputSym.getType();
|
|
Size = InputSym.st_size;
|
|
}
|
|
|
|
unsigned char Visibility = Body->getMostConstrainingVisibility();
|
|
if (Visibility != STV_DEFAULT && Visibility != STV_PROTECTED)
|
|
Binding = STB_LOCAL;
|
|
|
|
ESym->setBindingAndType(Binding, Type);
|
|
ESym->st_size = Size;
|
|
ESym->setVisibility(Visibility);
|
|
ESym->st_value = getSymVA(*Body, BssSec);
|
|
|
|
if (Section)
|
|
Out = Section->getOutputSection();
|
|
|
|
if (isa<DefinedAbsolute<ELFT>>(Body))
|
|
ESym->st_shndx = SHN_ABS;
|
|
else if (Out)
|
|
ESym->st_shndx = Out->getSectionIndex();
|
|
}
|
|
if (!StrTabSec.isDynamic())
|
|
std::stable_sort(
|
|
reinterpret_cast<Elf_Sym *>(Start), reinterpret_cast<Elf_Sym *>(Buf),
|
|
[](const Elf_Sym &A, const Elf_Sym &B) -> bool {
|
|
return A.getBinding() == STB_LOCAL && B.getBinding() != STB_LOCAL;
|
|
});
|
|
}
|
|
|
|
namespace lld {
|
|
namespace elf2 {
|
|
template class OutputSectionBase<false>;
|
|
template class OutputSectionBase<true>;
|
|
|
|
template void OutputSectionBase<false>::writeHeaderTo<support::little>(
|
|
ELFFile<ELFType<support::little, false>>::Elf_Shdr *SHdr);
|
|
template void OutputSectionBase<true>::writeHeaderTo<support::little>(
|
|
ELFFile<ELFType<support::little, true>>::Elf_Shdr *SHdr);
|
|
template void OutputSectionBase<false>::writeHeaderTo<support::big>(
|
|
ELFFile<ELFType<support::big, false>>::Elf_Shdr *SHdr);
|
|
template void OutputSectionBase<true>::writeHeaderTo<support::big>(
|
|
ELFFile<ELFType<support::big, true>>::Elf_Shdr *SHdr);
|
|
|
|
template class GotSection<ELF32LE>;
|
|
template class GotSection<ELF32BE>;
|
|
template class GotSection<ELF64LE>;
|
|
template class GotSection<ELF64BE>;
|
|
|
|
template class PltSection<ELF32LE>;
|
|
template class PltSection<ELF32BE>;
|
|
template class PltSection<ELF64LE>;
|
|
template class PltSection<ELF64BE>;
|
|
|
|
template class RelocationSection<ELF32LE>;
|
|
template class RelocationSection<ELF32BE>;
|
|
template class RelocationSection<ELF64LE>;
|
|
template class RelocationSection<ELF64BE>;
|
|
|
|
template class InterpSection<false>;
|
|
template class InterpSection<true>;
|
|
|
|
template class HashTableSection<ELF32LE>;
|
|
template class HashTableSection<ELF32BE>;
|
|
template class HashTableSection<ELF64LE>;
|
|
template class HashTableSection<ELF64BE>;
|
|
|
|
template class DynamicSection<ELF32LE>;
|
|
template class DynamicSection<ELF32BE>;
|
|
template class DynamicSection<ELF64LE>;
|
|
template class DynamicSection<ELF64BE>;
|
|
|
|
template class OutputSection<ELF32LE>;
|
|
template class OutputSection<ELF32BE>;
|
|
template class OutputSection<ELF64LE>;
|
|
template class OutputSection<ELF64BE>;
|
|
|
|
template class StringTableSection<false>;
|
|
template class StringTableSection<true>;
|
|
|
|
template class SymbolTableSection<ELF32LE>;
|
|
template class SymbolTableSection<ELF32BE>;
|
|
template class SymbolTableSection<ELF64LE>;
|
|
template class SymbolTableSection<ELF64BE>;
|
|
|
|
template ELFFile<ELF32LE>::uintX_t getSymVA(const SymbolBody &,
|
|
const OutputSection<ELF32LE> &);
|
|
template ELFFile<ELF32BE>::uintX_t getSymVA(const SymbolBody &,
|
|
const OutputSection<ELF32BE> &);
|
|
template ELFFile<ELF64LE>::uintX_t getSymVA(const SymbolBody &,
|
|
const OutputSection<ELF64LE> &);
|
|
template ELFFile<ELF64BE>::uintX_t getSymVA(const SymbolBody &,
|
|
const OutputSection<ELF64BE> &);
|
|
|
|
template ELFFile<ELF32LE>::uintX_t
|
|
getLocalSymVA(const ELFFile<ELF32LE>::Elf_Sym *, const ObjectFile<ELF32LE> &);
|
|
|
|
template ELFFile<ELF32BE>::uintX_t
|
|
getLocalSymVA(const ELFFile<ELF32BE>::Elf_Sym *, const ObjectFile<ELF32BE> &);
|
|
|
|
template ELFFile<ELF64LE>::uintX_t
|
|
getLocalSymVA(const ELFFile<ELF64LE>::Elf_Sym *, const ObjectFile<ELF64LE> &);
|
|
|
|
template ELFFile<ELF64BE>::uintX_t
|
|
getLocalSymVA(const ELFFile<ELF64BE>::Elf_Sym *, const ObjectFile<ELF64BE> &);
|
|
|
|
template bool includeInSymtab<ELF32LE>(const SymbolBody &);
|
|
template bool includeInSymtab<ELF32BE>(const SymbolBody &);
|
|
template bool includeInSymtab<ELF64LE>(const SymbolBody &);
|
|
template bool includeInSymtab<ELF64BE>(const SymbolBody &);
|
|
|
|
template bool shouldKeepInSymtab<ELF32LE>(StringRef,
|
|
const ELFFile<ELF32LE>::Elf_Sym &);
|
|
template bool shouldKeepInSymtab<ELF32BE>(StringRef,
|
|
const ELFFile<ELF32BE>::Elf_Sym &);
|
|
template bool shouldKeepInSymtab<ELF64LE>(StringRef,
|
|
const ELFFile<ELF64LE>::Elf_Sym &);
|
|
template bool shouldKeepInSymtab<ELF64BE>(StringRef,
|
|
const ELFFile<ELF64BE>::Elf_Sym &);
|
|
}
|
|
}
|