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-rw-r--r--lld/ELF/SyntheticSections.cpp180
1 files changed, 180 insertions, 0 deletions
diff --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index d432758bfa8..8e54ee7cbc5 100644
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -673,6 +673,181 @@ template <class ELFT> void StringTableSection<ELFT>::writeTo(uint8_t *Buf) {
}
}
+static unsigned getVerDefNum() { return Config->VersionDefinitions.size() + 1; }
+
+template <class ELFT>
+DynamicSection<ELFT>::DynamicSection()
+ : SyntheticSection<ELFT>(SHF_ALLOC | SHF_WRITE, SHT_DYNAMIC,
+ sizeof(uintX_t), ".dynamic") {
+ this->Entsize = ELFT::Is64Bits ? 16 : 8;
+ // .dynamic section is not writable on MIPS.
+ // See "Special Section" in Chapter 4 in the following document:
+ // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
+ if (Config->EMachine == EM_MIPS)
+ this->Flags = SHF_ALLOC;
+
+ addEntries();
+}
+
+// There are some dynamic entries that don't depend on other sections.
+// Such entries can be set early.
+template <class ELFT> void DynamicSection<ELFT>::addEntries() {
+ // Add strings to .dynstr early so that .dynstr's size will be
+ // fixed early.
+ for (StringRef S : Config->AuxiliaryList)
+ Add({DT_AUXILIARY, In<ELFT>::DynStrTab->addString(S)});
+ if (!Config->RPath.empty())
+ Add({Config->EnableNewDtags ? DT_RUNPATH : DT_RPATH,
+ In<ELFT>::DynStrTab->addString(Config->RPath)});
+ for (SharedFile<ELFT> *F : Symtab<ELFT>::X->getSharedFiles())
+ if (F->isNeeded())
+ Add({DT_NEEDED, In<ELFT>::DynStrTab->addString(F->getSoName())});
+ if (!Config->SoName.empty())
+ Add({DT_SONAME, In<ELFT>::DynStrTab->addString(Config->SoName)});
+
+ // Set DT_FLAGS and DT_FLAGS_1.
+ uint32_t DtFlags = 0;
+ uint32_t DtFlags1 = 0;
+ if (Config->Bsymbolic)
+ DtFlags |= DF_SYMBOLIC;
+ if (Config->ZNodelete)
+ DtFlags1 |= DF_1_NODELETE;
+ if (Config->ZNow) {
+ DtFlags |= DF_BIND_NOW;
+ DtFlags1 |= DF_1_NOW;
+ }
+ if (Config->ZOrigin) {
+ DtFlags |= DF_ORIGIN;
+ DtFlags1 |= DF_1_ORIGIN;
+ }
+
+ if (DtFlags)
+ Add({DT_FLAGS, DtFlags});
+ if (DtFlags1)
+ Add({DT_FLAGS_1, DtFlags1});
+
+ if (!Config->Entry.empty())
+ Add({DT_DEBUG, (uint64_t)0});
+}
+
+// Add remaining entries to complete .dynamic contents.
+template <class ELFT> void DynamicSection<ELFT>::finalize() {
+ if (this->Size)
+ return; // Already finalized.
+
+ this->Link = In<ELFT>::DynStrTab->OutSec->SectionIndex;
+
+ if (Out<ELFT>::RelaDyn->hasRelocs()) {
+ bool IsRela = Config->Rela;
+ Add({IsRela ? DT_RELA : DT_REL, Out<ELFT>::RelaDyn});
+ Add({IsRela ? DT_RELASZ : DT_RELSZ, Out<ELFT>::RelaDyn->Size});
+ Add({IsRela ? DT_RELAENT : DT_RELENT,
+ uintX_t(IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel))});
+
+ // MIPS dynamic loader does not support RELCOUNT tag.
+ // The problem is in the tight relation between dynamic
+ // relocations and GOT. So do not emit this tag on MIPS.
+ if (Config->EMachine != EM_MIPS) {
+ size_t NumRelativeRels = Out<ELFT>::RelaDyn->getRelativeRelocCount();
+ if (Config->ZCombreloc && NumRelativeRels)
+ Add({IsRela ? DT_RELACOUNT : DT_RELCOUNT, NumRelativeRels});
+ }
+ }
+ if (Out<ELFT>::RelaPlt && Out<ELFT>::RelaPlt->hasRelocs()) {
+ Add({DT_JMPREL, Out<ELFT>::RelaPlt});
+ Add({DT_PLTRELSZ, Out<ELFT>::RelaPlt->Size});
+ Add({Config->EMachine == EM_MIPS ? DT_MIPS_PLTGOT : DT_PLTGOT,
+ In<ELFT>::GotPlt});
+ Add({DT_PLTREL, uint64_t(Config->Rela ? DT_RELA : DT_REL)});
+ }
+
+ Add({DT_SYMTAB, Out<ELFT>::DynSymTab});
+ Add({DT_SYMENT, sizeof(Elf_Sym)});
+ Add({DT_STRTAB, In<ELFT>::DynStrTab});
+ Add({DT_STRSZ, In<ELFT>::DynStrTab->getSize()});
+ if (Out<ELFT>::GnuHashTab)
+ Add({DT_GNU_HASH, Out<ELFT>::GnuHashTab});
+ if (Out<ELFT>::HashTab)
+ Add({DT_HASH, Out<ELFT>::HashTab});
+
+ if (Out<ELFT>::PreinitArray) {
+ Add({DT_PREINIT_ARRAY, Out<ELFT>::PreinitArray});
+ Add({DT_PREINIT_ARRAYSZ, Out<ELFT>::PreinitArray, Entry::SecSize});
+ }
+ if (Out<ELFT>::InitArray) {
+ Add({DT_INIT_ARRAY, Out<ELFT>::InitArray});
+ Add({DT_INIT_ARRAYSZ, Out<ELFT>::InitArray, Entry::SecSize});
+ }
+ if (Out<ELFT>::FiniArray) {
+ Add({DT_FINI_ARRAY, Out<ELFT>::FiniArray});
+ Add({DT_FINI_ARRAYSZ, Out<ELFT>::FiniArray, Entry::SecSize});
+ }
+
+ if (SymbolBody *B = Symtab<ELFT>::X->find(Config->Init))
+ Add({DT_INIT, B});
+ if (SymbolBody *B = Symtab<ELFT>::X->find(Config->Fini))
+ Add({DT_FINI, B});
+
+ bool HasVerNeed = Out<ELFT>::VerNeed->getNeedNum() != 0;
+ if (HasVerNeed || Out<ELFT>::VerDef)
+ Add({DT_VERSYM, Out<ELFT>::VerSym});
+ if (Out<ELFT>::VerDef) {
+ Add({DT_VERDEF, Out<ELFT>::VerDef});
+ Add({DT_VERDEFNUM, getVerDefNum()});
+ }
+ if (HasVerNeed) {
+ Add({DT_VERNEED, Out<ELFT>::VerNeed});
+ Add({DT_VERNEEDNUM, Out<ELFT>::VerNeed->getNeedNum()});
+ }
+
+ if (Config->EMachine == EM_MIPS) {
+ Add({DT_MIPS_RLD_VERSION, 1});
+ Add({DT_MIPS_FLAGS, RHF_NOTPOT});
+ Add({DT_MIPS_BASE_ADDRESS, Config->ImageBase});
+ Add({DT_MIPS_SYMTABNO, Out<ELFT>::DynSymTab->getNumSymbols()});
+ Add({DT_MIPS_LOCAL_GOTNO, In<ELFT>::Got->getMipsLocalEntriesNum()});
+ if (const SymbolBody *B = In<ELFT>::Got->getMipsFirstGlobalEntry())
+ Add({DT_MIPS_GOTSYM, B->DynsymIndex});
+ else
+ Add({DT_MIPS_GOTSYM, Out<ELFT>::DynSymTab->getNumSymbols()});
+ Add({DT_PLTGOT, In<ELFT>::Got});
+ if (Out<ELFT>::MipsRldMap)
+ Add({DT_MIPS_RLD_MAP, Out<ELFT>::MipsRldMap});
+ }
+
+ this->OutSec->Entsize = this->Entsize;
+ this->OutSec->Link = this->Link;
+
+ // +1 for DT_NULL
+ this->Size = (Entries.size() + 1) * this->Entsize;
+}
+
+template <class ELFT> void DynamicSection<ELFT>::writeTo(uint8_t *Buf) {
+ auto *P = reinterpret_cast<Elf_Dyn *>(Buf);
+
+ for (const Entry &E : Entries) {
+ P->d_tag = E.Tag;
+ switch (E.Kind) {
+ case Entry::SecAddr:
+ P->d_un.d_ptr = E.OutSec->Addr;
+ break;
+ case Entry::InSecAddr:
+ P->d_un.d_ptr = E.InSec->OutSec->Addr + E.InSec->OutSecOff;
+ break;
+ case Entry::SecSize:
+ P->d_un.d_val = E.OutSec->Size;
+ break;
+ case Entry::SymAddr:
+ P->d_un.d_ptr = E.Sym->template getVA<ELFT>();
+ break;
+ case Entry::PlainInt:
+ P->d_un.d_val = E.Val;
+ break;
+ }
+ ++P;
+ }
+}
+
template InputSection<ELF32LE> *elf::createCommonSection();
template InputSection<ELF32BE> *elf::createCommonSection();
template InputSection<ELF64LE> *elf::createCommonSection();
@@ -747,3 +922,8 @@ template class elf::StringTableSection<ELF32LE>;
template class elf::StringTableSection<ELF32BE>;
template class elf::StringTableSection<ELF64LE>;
template class elf::StringTableSection<ELF64BE>;
+
+template class elf::DynamicSection<ELF32LE>;
+template class elf::DynamicSection<ELF32BE>;
+template class elf::DynamicSection<ELF64LE>;
+template class elf::DynamicSection<ELF64BE>;
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