diff options
-rw-r--r-- | lld/ELF/OutputSections.cpp | 36 | ||||
-rw-r--r-- | lld/ELF/Target.cpp | 25 | ||||
-rw-r--r-- | lld/ELF/Target.h | 2 |
3 files changed, 28 insertions, 35 deletions
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp index efcfcb30b9f..6eeaa3ffc8e 100644 --- a/lld/ELF/OutputSections.cpp +++ b/lld/ELF/OutputSections.cpp @@ -146,7 +146,7 @@ template <class ELFT> void GotSection<ELFT>::addEntry(SymbolBody &Sym) { template <class ELFT> bool GotSection<ELFT>::addDynTlsEntry(SymbolBody &Sym) { if (Sym.hasGlobalDynIndex()) return false; - Sym.GlobalDynIndex = Target->GotHeaderEntriesNum + Entries.size(); + Sym.GlobalDynIndex = Entries.size(); // Global Dynamic TLS entries take two GOT slots. Entries.push_back(&Sym); Entries.push_back(nullptr); @@ -175,7 +175,9 @@ GotSection<ELFT>::getMipsLocalPageOffset(uintX_t EntryValue) { template <class ELFT> typename GotSection<ELFT>::uintX_t GotSection<ELFT>::getMipsLocalEntryOffset(uintX_t EntryValue) { - size_t NewIndex = Target->GotHeaderEntriesNum + MipsLocalGotPos.size(); + // 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() <= MipsLocalEntries); return P.first->second * sizeof(uintX_t) - MipsGPOffset; @@ -200,10 +202,14 @@ const SymbolBody *GotSection<ELFT>::getMipsFirstGlobalEntry() const { template <class ELFT> unsigned GotSection<ELFT>::getMipsLocalEntriesNum() const { - return Target->GotHeaderEntriesNum + MipsLocalEntries; + return MipsLocalEntries; } template <class ELFT> void GotSection<ELFT>::finalize() { + if (Config->EMachine == EM_MIPS) + // Take into account MIPS GOT header. + // See comment in the GotSection::writeTo. + MipsLocalEntries += 2; for (const OutputSectionBase<ELFT> *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 @@ -212,18 +218,32 @@ template <class ELFT> void GotSection<ELFT>::finalize() { // in the GOT entry is calculated as (value + 0x8000) & ~0xffff. MipsLocalEntries += (OutSec->getSize() + 0x8000 + 0xfffe) / 0xffff; } - this->Header.sh_size = - (Target->GotHeaderEntriesNum + MipsLocalEntries + Entries.size()) * - sizeof(uintX_t); + this->Header.sh_size = (MipsLocalEntries + Entries.size()) * sizeof(uintX_t); } template <class ELFT> void GotSection<ELFT>::writeTo(uint8_t *Buf) { - Target->writeGotHeader(Buf); + if (Config->EMachine == EM_MIPS) { + // 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<typename ELFT::Off *>(Buf); + P[1] = uintX_t(1) << (ELFT::Is64Bits ? 63 : 31); + } for (std::pair<uintX_t, size_t> &L : MipsLocalGotPos) { uint8_t *Entry = Buf + L.second * sizeof(uintX_t); write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Entry, L.first); } - Buf += Target->GotHeaderEntriesNum * sizeof(uintX_t); Buf += MipsLocalEntries * sizeof(uintX_t); for (const SymbolBody *B : Entries) { uint8_t *Entry = Buf; diff --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp index 31d72bbc0e1..bc846a03cb4 100644 --- a/lld/ELF/Target.cpp +++ b/lld/ELF/Target.cpp @@ -179,7 +179,6 @@ public: void writePltZero(uint8_t *Buf) const override; void writePlt(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr, int32_t Index, unsigned RelOff) const override; - void writeGotHeader(uint8_t *Buf) const override; void writeThunk(uint8_t *Buf, uint64_t S) const override; bool needsThunk(uint32_t Type, const InputFile &File, const SymbolBody &S) const override; @@ -1294,7 +1293,6 @@ RelExpr AMDGPUTargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S) const { } template <class ELFT> MipsTargetInfo<ELFT>::MipsTargetInfo() { - GotHeaderEntriesNum = 2; GotPltHeaderEntriesNum = 2; PageSize = 65536; PltEntrySize = 16; @@ -1353,29 +1351,6 @@ uint32_t MipsTargetInfo<ELFT>::getDynRel(uint32_t Type) const { } template <class ELFT> -void MipsTargetInfo<ELFT>::writeGotHeader(uint8_t *Buf) const { - typedef typename ELFT::Off Elf_Off; - typedef typename ELFT::uint uintX_t; - - // 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<Elf_Off *>(Buf); - P[1] = uintX_t(1) << (ELFT::Is64Bits ? 63 : 31); -} - -template <class ELFT> void MipsTargetInfo<ELFT>::writeGotPlt(uint8_t *Buf, uint64_t Plt) const { write32<ELFT::TargetEndianness>(Buf, Out<ELFT>::Plt->getVA()); } diff --git a/lld/ELF/Target.h b/lld/ELF/Target.h index 7a74e748190..cb743c754b4 100644 --- a/lld/ELF/Target.h +++ b/lld/ELF/Target.h @@ -29,7 +29,6 @@ public: virtual bool isTlsGlobalDynamicRel(uint32_t Type) const; virtual uint32_t getDynRel(uint32_t Type) const { return Type; } virtual uint32_t getTlsGotRel(uint32_t Type) const { return TlsGotRel; } - virtual void writeGotHeader(uint8_t *Buf) const {} virtual void writeGotPltHeader(uint8_t *Buf) const {} virtual void writeGotPlt(uint8_t *Buf, uint64_t Plt) const {}; virtual uint64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const; @@ -85,7 +84,6 @@ public: uint32_t TlsOffsetRel; unsigned PltEntrySize = 8; unsigned PltZeroSize = 0; - unsigned GotHeaderEntriesNum = 0; unsigned GotPltHeaderEntriesNum = 3; uint32_t ThunkSize = 0; bool UseLazyBinding = false; |