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-rw-r--r--gnu/llvm/tools/lld/ELF/InputSection.cpp691
1 files changed, 691 insertions, 0 deletions
diff --git a/gnu/llvm/tools/lld/ELF/InputSection.cpp b/gnu/llvm/tools/lld/ELF/InputSection.cpp
new file mode 100644
index 00000000000..6564e7995a8
--- /dev/null
+++ b/gnu/llvm/tools/lld/ELF/InputSection.cpp
@@ -0,0 +1,691 @@
+//===- InputSection.cpp ---------------------------------------------------===//
+//
+// The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "InputSection.h"
+#include "Config.h"
+#include "EhFrame.h"
+#include "Error.h"
+#include "InputFiles.h"
+#include "LinkerScript.h"
+#include "OutputSections.h"
+#include "Target.h"
+#include "Thunks.h"
+
+#include "llvm/Support/Compression.h"
+#include "llvm/Support/Endian.h"
+
+using namespace llvm;
+using namespace llvm::ELF;
+using namespace llvm::object;
+using namespace llvm::support::endian;
+
+using namespace lld;
+using namespace lld::elf;
+
+template <class ELFT> bool elf::isDiscarded(InputSectionBase<ELFT> *S) {
+ return !S || S == &InputSection<ELFT>::Discarded || !S->Live ||
+ Script<ELFT>::X->isDiscarded(S);
+}
+
+template <class ELFT>
+InputSectionBase<ELFT>::InputSectionBase(elf::ObjectFile<ELFT> *File,
+ const Elf_Shdr *Header,
+ Kind SectionKind)
+ : Header(Header), File(File), SectionKind(SectionKind), Repl(this),
+ Compressed(Header->sh_flags & SHF_COMPRESSED) {
+ // The garbage collector sets sections' Live bits.
+ // If GC is disabled, all sections are considered live by default.
+ Live = !Config->GcSections;
+
+ // The ELF spec states that a value of 0 means the section has
+ // no alignment constraits.
+ Alignment = std::max<uintX_t>(Header->sh_addralign, 1);
+}
+
+template <class ELFT> size_t InputSectionBase<ELFT>::getSize() const {
+ if (auto *D = dyn_cast<InputSection<ELFT>>(this))
+ if (D->getThunksSize() > 0)
+ return D->getThunkOff() + D->getThunksSize();
+ return Header->sh_size;
+}
+
+template <class ELFT> StringRef InputSectionBase<ELFT>::getSectionName() const {
+ return check(File->getObj().getSectionName(this->Header));
+}
+
+template <class ELFT>
+ArrayRef<uint8_t> InputSectionBase<ELFT>::getSectionData() const {
+ if (Compressed)
+ return ArrayRef<uint8_t>((const uint8_t *)Uncompressed.data(),
+ Uncompressed.size());
+ return check(this->File->getObj().getSectionContents(this->Header));
+}
+
+template <class ELFT>
+typename ELFT::uint InputSectionBase<ELFT>::getOffset(uintX_t Offset) const {
+ switch (SectionKind) {
+ case Regular:
+ return cast<InputSection<ELFT>>(this)->OutSecOff + Offset;
+ case EHFrame:
+ return cast<EhInputSection<ELFT>>(this)->getOffset(Offset);
+ case Merge:
+ return cast<MergeInputSection<ELFT>>(this)->getOffset(Offset);
+ case MipsReginfo:
+ case MipsOptions:
+ // MIPS .reginfo and .MIPS.options sections are consumed by the linker,
+ // and the linker produces a single output section. It is possible that
+ // input files contain section symbol points to the corresponding input
+ // section. Redirect it to the produced output section.
+ if (Offset != 0)
+ fatal("Unsupported reference to the middle of '" + getSectionName() +
+ "' section");
+ return this->OutSec->getVA();
+ }
+ llvm_unreachable("invalid section kind");
+}
+
+template <class ELFT> void InputSectionBase<ELFT>::uncompress() {
+ if (!zlib::isAvailable())
+ fatal("build lld with zlib to enable compressed sections support");
+
+ // A compressed section consists of a header of Elf_Chdr type
+ // followed by compressed data.
+ ArrayRef<uint8_t> Data =
+ check(this->File->getObj().getSectionContents(this->Header));
+ if (Data.size() < sizeof(Elf_Chdr))
+ fatal("corrupt compressed section");
+
+ auto *Hdr = reinterpret_cast<const Elf_Chdr *>(Data.data());
+ Data = Data.slice(sizeof(Elf_Chdr));
+
+ if (Hdr->ch_type != ELFCOMPRESS_ZLIB)
+ fatal("unsupported compression type");
+
+ StringRef Buf((const char *)Data.data(), Data.size());
+ if (zlib::uncompress(Buf, Uncompressed, Hdr->ch_size) != zlib::StatusOK)
+ fatal("error uncompressing section");
+}
+
+template <class ELFT>
+typename ELFT::uint
+InputSectionBase<ELFT>::getOffset(const DefinedRegular<ELFT> &Sym) const {
+ return getOffset(Sym.Value);
+}
+
+template <class ELFT>
+InputSection<ELFT>::InputSection(elf::ObjectFile<ELFT> *F,
+ const Elf_Shdr *Header)
+ : InputSectionBase<ELFT>(F, Header, Base::Regular) {}
+
+template <class ELFT>
+bool InputSection<ELFT>::classof(const InputSectionBase<ELFT> *S) {
+ return S->SectionKind == Base::Regular;
+}
+
+template <class ELFT>
+InputSectionBase<ELFT> *InputSection<ELFT>::getRelocatedSection() {
+ assert(this->Header->sh_type == SHT_RELA || this->Header->sh_type == SHT_REL);
+ ArrayRef<InputSectionBase<ELFT> *> Sections = this->File->getSections();
+ return Sections[this->Header->sh_info];
+}
+
+template <class ELFT>
+void InputSection<ELFT>::addThunk(const Thunk<ELFT> *T) {
+ Thunks.push_back(T);
+}
+
+template <class ELFT> uint64_t InputSection<ELFT>::getThunkOff() const {
+ return this->Header->sh_size;
+}
+
+template <class ELFT> uint64_t InputSection<ELFT>::getThunksSize() const {
+ uint64_t Total = 0;
+ for (const Thunk<ELFT> *T : Thunks)
+ Total += T->size();
+ return Total;
+}
+
+// This is used for -r. We can't use memcpy to copy relocations because we need
+// to update symbol table offset and section index for each relocation. So we
+// copy relocations one by one.
+template <class ELFT>
+template <class RelTy>
+void InputSection<ELFT>::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
+ InputSectionBase<ELFT> *RelocatedSection = getRelocatedSection();
+
+ for (const RelTy &Rel : Rels) {
+ uint32_t Type = Rel.getType(Config->Mips64EL);
+ SymbolBody &Body = this->File->getRelocTargetSym(Rel);
+
+ RelTy *P = reinterpret_cast<RelTy *>(Buf);
+ Buf += sizeof(RelTy);
+
+ P->r_offset = RelocatedSection->getOffset(Rel.r_offset);
+ P->setSymbolAndType(Body.DynsymIndex, Type, Config->Mips64EL);
+ }
+}
+
+// Page(Expr) is the page address of the expression Expr, defined
+// as (Expr & ~0xFFF). (This applies even if the machine page size
+// supported by the platform has a different value.)
+static uint64_t getAArch64Page(uint64_t Expr) {
+ return Expr & (~static_cast<uint64_t>(0xFFF));
+}
+
+template <class ELFT>
+static typename ELFT::uint getSymVA(uint32_t Type, typename ELFT::uint A,
+ typename ELFT::uint P,
+ const SymbolBody &Body, RelExpr Expr) {
+ typedef typename ELFT::uint uintX_t;
+
+ switch (Expr) {
+ case R_HINT:
+ llvm_unreachable("cannot relocate hint relocs");
+ case R_TLSLD:
+ return Out<ELFT>::Got->getTlsIndexOff() + A -
+ Out<ELFT>::Got->getNumEntries() * sizeof(uintX_t);
+ case R_TLSLD_PC:
+ return Out<ELFT>::Got->getTlsIndexVA() + A - P;
+ case R_THUNK_ABS:
+ return Body.getThunkVA<ELFT>() + A;
+ case R_THUNK_PC:
+ case R_THUNK_PLT_PC:
+ return Body.getThunkVA<ELFT>() + A - P;
+ case R_PPC_TOC:
+ return getPPC64TocBase() + A;
+ case R_TLSGD:
+ return Out<ELFT>::Got->getGlobalDynOffset(Body) + A -
+ Out<ELFT>::Got->getNumEntries() * sizeof(uintX_t);
+ case R_TLSGD_PC:
+ return Out<ELFT>::Got->getGlobalDynAddr(Body) + A - P;
+ case R_TLSDESC:
+ return Out<ELFT>::Got->getGlobalDynAddr(Body) + A;
+ case R_TLSDESC_PAGE:
+ return getAArch64Page(Out<ELFT>::Got->getGlobalDynAddr(Body) + A) -
+ getAArch64Page(P);
+ case R_PLT:
+ return Body.getPltVA<ELFT>() + A;
+ case R_PLT_PC:
+ case R_PPC_PLT_OPD:
+ return Body.getPltVA<ELFT>() + A - P;
+ case R_SIZE:
+ return Body.getSize<ELFT>() + A;
+ case R_GOTREL:
+ return Body.getVA<ELFT>(A) - Out<ELFT>::Got->getVA();
+ case R_RELAX_TLS_GD_TO_IE_END:
+ case R_GOT_FROM_END:
+ return Body.getGotOffset<ELFT>() + A -
+ Out<ELFT>::Got->getNumEntries() * sizeof(uintX_t);
+ case R_RELAX_TLS_GD_TO_IE_ABS:
+ case R_GOT:
+ return Body.getGotVA<ELFT>() + A;
+ case R_RELAX_TLS_GD_TO_IE_PAGE_PC:
+ case R_GOT_PAGE_PC:
+ return getAArch64Page(Body.getGotVA<ELFT>() + A) - getAArch64Page(P);
+ case R_RELAX_TLS_GD_TO_IE:
+ case R_GOT_PC:
+ return Body.getGotVA<ELFT>() + A - P;
+ case R_GOTONLY_PC:
+ return Out<ELFT>::Got->getVA() + A - P;
+ case R_RELAX_TLS_LD_TO_LE:
+ case R_RELAX_TLS_IE_TO_LE:
+ case R_RELAX_TLS_GD_TO_LE:
+ case R_TLS:
+ if (Target->TcbSize)
+ return Body.getVA<ELFT>(A) +
+ alignTo(Target->TcbSize, Out<ELFT>::TlsPhdr->p_align);
+ return Body.getVA<ELFT>(A) - Out<ELFT>::TlsPhdr->p_memsz;
+ case R_RELAX_TLS_GD_TO_LE_NEG:
+ case R_NEG_TLS:
+ return Out<ELF32LE>::TlsPhdr->p_memsz - Body.getVA<ELFT>(A);
+ case R_ABS:
+ case R_RELAX_GOT_PC_NOPIC:
+ return Body.getVA<ELFT>(A);
+ case R_GOT_OFF:
+ return Body.getGotOffset<ELFT>() + A;
+ case R_MIPS_GOT_LOCAL_PAGE:
+ // If relocation against MIPS local symbol requires GOT entry, this entry
+ // should be initialized by 'page address'. This address is high 16-bits
+ // of sum the symbol's value and the addend.
+ return Out<ELFT>::Got->getMipsLocalPageOffset(Body.getVA<ELFT>(A));
+ case R_MIPS_GOT_OFF:
+ // In case of MIPS if a GOT relocation has non-zero addend this addend
+ // should be applied to the GOT entry content not to the GOT entry offset.
+ // That is why we use separate expression type.
+ return Out<ELFT>::Got->getMipsGotOffset(Body, A);
+ case R_MIPS_TLSGD:
+ return Out<ELFT>::Got->getGlobalDynOffset(Body) +
+ Out<ELFT>::Got->getMipsTlsOffset() - MipsGPOffset;
+ case R_MIPS_TLSLD:
+ return Out<ELFT>::Got->getTlsIndexOff() +
+ Out<ELFT>::Got->getMipsTlsOffset() - MipsGPOffset;
+ case R_PPC_OPD: {
+ uint64_t SymVA = Body.getVA<ELFT>(A);
+ // If we have an undefined weak symbol, we might get here with a symbol
+ // address of zero. That could overflow, but the code must be unreachable,
+ // so don't bother doing anything at all.
+ if (!SymVA)
+ return 0;
+ if (Out<ELF64BE>::Opd) {
+ // If this is a local call, and we currently have the address of a
+ // function-descriptor, get the underlying code address instead.
+ uint64_t OpdStart = Out<ELF64BE>::Opd->getVA();
+ uint64_t OpdEnd = OpdStart + Out<ELF64BE>::Opd->getSize();
+ bool InOpd = OpdStart <= SymVA && SymVA < OpdEnd;
+ if (InOpd)
+ SymVA = read64be(&Out<ELF64BE>::OpdBuf[SymVA - OpdStart]);
+ }
+ return SymVA - P;
+ }
+ case R_PC:
+ case R_RELAX_GOT_PC:
+ return Body.getVA<ELFT>(A) - P;
+ case R_PLT_PAGE_PC:
+ case R_PAGE_PC:
+ return getAArch64Page(Body.getVA<ELFT>(A)) - getAArch64Page(P);
+ }
+ llvm_unreachable("Invalid expression");
+}
+
+// This function applies relocations to sections without SHF_ALLOC bit.
+// Such sections are never mapped to memory at runtime. Debug sections are
+// an example. Relocations in non-alloc sections are much easier to
+// handle than in allocated sections because it will never need complex
+// treatement such as GOT or PLT (because at runtime no one refers them).
+// So, we handle relocations for non-alloc sections directly in this
+// function as a performance optimization.
+template <class ELFT>
+template <class RelTy>
+void InputSection<ELFT>::relocateNonAlloc(uint8_t *Buf, ArrayRef<RelTy> Rels) {
+ const unsigned Bits = sizeof(uintX_t) * 8;
+ for (const RelTy &Rel : Rels) {
+ uint32_t Type = Rel.getType(Config->Mips64EL);
+ uintX_t Offset = this->getOffset(Rel.r_offset);
+ uint8_t *BufLoc = Buf + Offset;
+ uintX_t Addend = getAddend<ELFT>(Rel);
+ if (!RelTy::IsRela)
+ Addend += Target->getImplicitAddend(BufLoc, Type);
+
+ SymbolBody &Sym = this->File->getRelocTargetSym(Rel);
+ if (Target->getRelExpr(Type, Sym) != R_ABS) {
+ error(this->getSectionName() + " has non-ABS reloc");
+ return;
+ }
+
+ uintX_t AddrLoc = this->OutSec->getVA() + Offset;
+ uint64_t SymVA =
+ SignExtend64<Bits>(getSymVA<ELFT>(Type, Addend, AddrLoc, Sym, R_ABS));
+ Target->relocateOne(BufLoc, Type, SymVA);
+ }
+}
+
+template <class ELFT>
+void InputSectionBase<ELFT>::relocate(uint8_t *Buf, uint8_t *BufEnd) {
+ // scanReloc function in Writer.cpp constructs Relocations
+ // vector only for SHF_ALLOC'ed sections. For other sections,
+ // we handle relocations directly here.
+ auto *IS = dyn_cast<InputSection<ELFT>>(this);
+ if (IS && !(IS->Header->sh_flags & SHF_ALLOC)) {
+ for (const Elf_Shdr *RelSec : IS->RelocSections) {
+ if (RelSec->sh_type == SHT_RELA)
+ IS->relocateNonAlloc(Buf, IS->File->getObj().relas(RelSec));
+ else
+ IS->relocateNonAlloc(Buf, IS->File->getObj().rels(RelSec));
+ }
+ return;
+ }
+
+ const unsigned Bits = sizeof(uintX_t) * 8;
+ for (const Relocation<ELFT> &Rel : Relocations) {
+ uintX_t Offset = Rel.InputSec->getOffset(Rel.Offset);
+ uint8_t *BufLoc = Buf + Offset;
+ uint32_t Type = Rel.Type;
+ uintX_t A = Rel.Addend;
+
+ uintX_t AddrLoc = OutSec->getVA() + Offset;
+ RelExpr Expr = Rel.Expr;
+ uint64_t SymVA =
+ SignExtend64<Bits>(getSymVA<ELFT>(Type, A, AddrLoc, *Rel.Sym, Expr));
+
+ switch (Expr) {
+ case R_RELAX_GOT_PC:
+ case R_RELAX_GOT_PC_NOPIC:
+ Target->relaxGot(BufLoc, SymVA);
+ break;
+ case R_RELAX_TLS_IE_TO_LE:
+ Target->relaxTlsIeToLe(BufLoc, Type, SymVA);
+ break;
+ case R_RELAX_TLS_LD_TO_LE:
+ Target->relaxTlsLdToLe(BufLoc, Type, SymVA);
+ break;
+ case R_RELAX_TLS_GD_TO_LE:
+ case R_RELAX_TLS_GD_TO_LE_NEG:
+ Target->relaxTlsGdToLe(BufLoc, Type, SymVA);
+ break;
+ case R_RELAX_TLS_GD_TO_IE:
+ case R_RELAX_TLS_GD_TO_IE_ABS:
+ case R_RELAX_TLS_GD_TO_IE_PAGE_PC:
+ case R_RELAX_TLS_GD_TO_IE_END:
+ Target->relaxTlsGdToIe(BufLoc, Type, SymVA);
+ break;
+ case R_PPC_PLT_OPD:
+ // Patch a nop (0x60000000) to a ld.
+ if (BufLoc + 8 <= BufEnd && read32be(BufLoc + 4) == 0x60000000)
+ write32be(BufLoc + 4, 0xe8410028); // ld %r2, 40(%r1)
+ // fallthrough
+ default:
+ Target->relocateOne(BufLoc, Type, SymVA);
+ break;
+ }
+ }
+}
+
+template <class ELFT> void InputSection<ELFT>::writeTo(uint8_t *Buf) {
+ if (this->Header->sh_type == SHT_NOBITS)
+ return;
+ ELFFile<ELFT> &EObj = this->File->getObj();
+
+ // If -r is given, then an InputSection may be a relocation section.
+ if (this->Header->sh_type == SHT_RELA) {
+ copyRelocations(Buf + OutSecOff, EObj.relas(this->Header));
+ return;
+ }
+ if (this->Header->sh_type == SHT_REL) {
+ copyRelocations(Buf + OutSecOff, EObj.rels(this->Header));
+ return;
+ }
+
+ // Copy section contents from source object file to output file.
+ ArrayRef<uint8_t> Data = this->getSectionData();
+ memcpy(Buf + OutSecOff, Data.data(), Data.size());
+
+ // Iterate over all relocation sections that apply to this section.
+ uint8_t *BufEnd = Buf + OutSecOff + Data.size();
+ this->relocate(Buf, BufEnd);
+
+ // The section might have a data/code generated by the linker and need
+ // to be written after the section. Usually these are thunks - small piece
+ // of code used to jump between "incompatible" functions like PIC and non-PIC
+ // or if the jump target too far and its address does not fit to the short
+ // jump istruction.
+ if (!Thunks.empty()) {
+ Buf += OutSecOff + getThunkOff();
+ for (const Thunk<ELFT> *T : Thunks) {
+ T->writeTo(Buf);
+ Buf += T->size();
+ }
+ }
+}
+
+template <class ELFT>
+void InputSection<ELFT>::replace(InputSection<ELFT> *Other) {
+ this->Alignment = std::max(this->Alignment, Other->Alignment);
+ Other->Repl = this->Repl;
+ Other->Live = false;
+}
+
+template <class ELFT>
+SplitInputSection<ELFT>::SplitInputSection(
+ elf::ObjectFile<ELFT> *File, const Elf_Shdr *Header,
+ typename InputSectionBase<ELFT>::Kind SectionKind)
+ : InputSectionBase<ELFT>(File, Header, SectionKind) {}
+
+template <class ELFT>
+EhInputSection<ELFT>::EhInputSection(elf::ObjectFile<ELFT> *F,
+ const Elf_Shdr *Header)
+ : SplitInputSection<ELFT>(F, Header, InputSectionBase<ELFT>::EHFrame) {
+ // Mark .eh_frame sections as live by default because there are
+ // usually no relocations that point to .eh_frames. Otherwise,
+ // the garbage collector would drop all .eh_frame sections.
+ this->Live = true;
+}
+
+template <class ELFT>
+bool EhInputSection<ELFT>::classof(const InputSectionBase<ELFT> *S) {
+ return S->SectionKind == InputSectionBase<ELFT>::EHFrame;
+}
+
+// .eh_frame is a sequence of CIE or FDE records.
+// This function splits an input section into records and returns them.
+template <class ELFT>
+void EhInputSection<ELFT>::split() {
+ ArrayRef<uint8_t> Data = this->getSectionData();
+ for (size_t Off = 0, End = Data.size(); Off != End;) {
+ size_t Size = readEhRecordSize<ELFT>(Data.slice(Off));
+ this->Pieces.emplace_back(Off, Data.slice(Off, Size));
+ // The empty record is the end marker.
+ if (Size == 4)
+ break;
+ Off += Size;
+ }
+}
+
+template <class ELFT>
+typename ELFT::uint EhInputSection<ELFT>::getOffset(uintX_t Offset) const {
+ // The file crtbeginT.o has relocations pointing to the start of an empty
+ // .eh_frame that is known to be the first in the link. It does that to
+ // identify the start of the output .eh_frame. Handle this special case.
+ if (this->getSectionHdr()->sh_size == 0)
+ return Offset;
+ const SectionPiece *Piece = this->getSectionPiece(Offset);
+ if (Piece->OutputOff == size_t(-1))
+ return -1; // Not in the output
+
+ uintX_t Addend = Offset - Piece->InputOff;
+ return Piece->OutputOff + Addend;
+}
+
+static size_t findNull(ArrayRef<uint8_t> A, size_t EntSize) {
+ // Optimize the common case.
+ StringRef S((const char *)A.data(), A.size());
+ 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;
+}
+
+// Split SHF_STRINGS section. Such section is a sequence of
+// null-terminated strings.
+static std::vector<SectionPiece> splitStrings(ArrayRef<uint8_t> Data,
+ size_t EntSize) {
+ std::vector<SectionPiece> V;
+ size_t Off = 0;
+ while (!Data.empty()) {
+ size_t End = findNull(Data, EntSize);
+ if (End == StringRef::npos)
+ fatal("string is not null terminated");
+ size_t Size = End + EntSize;
+ V.emplace_back(Off, Data.slice(0, Size));
+ Data = Data.slice(Size);
+ Off += Size;
+ }
+ return V;
+}
+
+// Split non-SHF_STRINGS section. Such section is a sequence of
+// fixed size records.
+static std::vector<SectionPiece> splitNonStrings(ArrayRef<uint8_t> Data,
+ size_t EntSize) {
+ std::vector<SectionPiece> V;
+ size_t Size = Data.size();
+ assert((Size % EntSize) == 0);
+ for (unsigned I = 0, N = Size; I != N; I += EntSize)
+ V.emplace_back(I, Data.slice(I, EntSize));
+ return V;
+}
+
+template <class ELFT>
+MergeInputSection<ELFT>::MergeInputSection(elf::ObjectFile<ELFT> *F,
+ const Elf_Shdr *Header)
+ : SplitInputSection<ELFT>(F, Header, InputSectionBase<ELFT>::Merge) {}
+
+template <class ELFT> void MergeInputSection<ELFT>::splitIntoPieces() {
+ ArrayRef<uint8_t> Data = this->getSectionData();
+ uintX_t EntSize = this->Header->sh_entsize;
+ if (this->Header->sh_flags & SHF_STRINGS)
+ this->Pieces = splitStrings(Data, EntSize);
+ else
+ this->Pieces = splitNonStrings(Data, EntSize);
+
+ if (Config->GcSections)
+ for (uintX_t Off : LiveOffsets)
+ this->getSectionPiece(Off)->Live = true;
+}
+
+template <class ELFT>
+bool MergeInputSection<ELFT>::classof(const InputSectionBase<ELFT> *S) {
+ return S->SectionKind == InputSectionBase<ELFT>::Merge;
+}
+
+// Do binary search to get a section piece at a given input offset.
+template <class ELFT>
+SectionPiece *SplitInputSection<ELFT>::getSectionPiece(uintX_t Offset) {
+ auto *This = static_cast<const SplitInputSection<ELFT> *>(this);
+ return const_cast<SectionPiece *>(This->getSectionPiece(Offset));
+}
+
+template <class ELFT>
+const SectionPiece *
+SplitInputSection<ELFT>::getSectionPiece(uintX_t Offset) const {
+ ArrayRef<uint8_t> D = this->getSectionData();
+ StringRef Data((const char *)D.data(), D.size());
+ uintX_t Size = Data.size();
+ if (Offset >= Size)
+ fatal("entry is past the end of the section");
+
+ // Find the element this offset points to.
+ auto I = std::upper_bound(
+ Pieces.begin(), Pieces.end(), Offset,
+ [](const uintX_t &A, const SectionPiece &B) { return A < B.InputOff; });
+ --I;
+ return &*I;
+}
+
+// Returns the offset in an output section for a given input offset.
+// Because contents of a mergeable section is not contiguous in output,
+// it is not just an addition to a base output offset.
+template <class ELFT>
+typename ELFT::uint MergeInputSection<ELFT>::getOffset(uintX_t Offset) const {
+ auto It = OffsetMap.find(Offset);
+ if (It != OffsetMap.end())
+ return It->second;
+
+ // If Offset is not at beginning of a section piece, it is not in the map.
+ // In that case we need to search from the original section piece vector.
+ const SectionPiece &Piece = *this->getSectionPiece(Offset);
+ assert(Piece.Live);
+ uintX_t Addend = Offset - Piece.InputOff;
+ return Piece.OutputOff + Addend;
+}
+
+// Create a map from input offsets to output offsets for all section pieces.
+// It is called after finalize().
+template <class ELFT> void MergeInputSection<ELFT>::finalizePieces() {
+ OffsetMap.grow(this->Pieces.size());
+ for (SectionPiece &Piece : this->Pieces) {
+ if (!Piece.Live)
+ continue;
+ if (Piece.OutputOff == size_t(-1)) {
+ // Offsets of tail-merged strings are computed lazily.
+ auto *OutSec = static_cast<MergeOutputSection<ELFT> *>(this->OutSec);
+ ArrayRef<uint8_t> D = Piece.data();
+ StringRef S((const char *)D.data(), D.size());
+ Piece.OutputOff = OutSec->getOffset(S);
+ }
+ OffsetMap[Piece.InputOff] = Piece.OutputOff;
+ }
+}
+
+template <class ELFT>
+MipsReginfoInputSection<ELFT>::MipsReginfoInputSection(elf::ObjectFile<ELFT> *F,
+ const Elf_Shdr *Hdr)
+ : InputSectionBase<ELFT>(F, Hdr, InputSectionBase<ELFT>::MipsReginfo) {
+ // Initialize this->Reginfo.
+ ArrayRef<uint8_t> D = this->getSectionData();
+ if (D.size() != sizeof(Elf_Mips_RegInfo<ELFT>)) {
+ error("invalid size of .reginfo section");
+ return;
+ }
+ Reginfo = reinterpret_cast<const Elf_Mips_RegInfo<ELFT> *>(D.data());
+}
+
+template <class ELFT>
+bool MipsReginfoInputSection<ELFT>::classof(const InputSectionBase<ELFT> *S) {
+ return S->SectionKind == InputSectionBase<ELFT>::MipsReginfo;
+}
+
+template <class ELFT>
+MipsOptionsInputSection<ELFT>::MipsOptionsInputSection(elf::ObjectFile<ELFT> *F,
+ const Elf_Shdr *Hdr)
+ : InputSectionBase<ELFT>(F, Hdr, InputSectionBase<ELFT>::MipsOptions) {
+ // Find ODK_REGINFO option in the section's content.
+ ArrayRef<uint8_t> D = this->getSectionData();
+ while (!D.empty()) {
+ if (D.size() < sizeof(Elf_Mips_Options<ELFT>)) {
+ error("invalid size of .MIPS.options section");
+ break;
+ }
+ auto *O = reinterpret_cast<const Elf_Mips_Options<ELFT> *>(D.data());
+ if (O->kind == ODK_REGINFO) {
+ Reginfo = &O->getRegInfo();
+ break;
+ }
+ D = D.slice(O->size);
+ }
+}
+
+template <class ELFT>
+bool MipsOptionsInputSection<ELFT>::classof(const InputSectionBase<ELFT> *S) {
+ return S->SectionKind == InputSectionBase<ELFT>::MipsOptions;
+}
+
+template bool elf::isDiscarded<ELF32LE>(InputSectionBase<ELF32LE> *);
+template bool elf::isDiscarded<ELF32BE>(InputSectionBase<ELF32BE> *);
+template bool elf::isDiscarded<ELF64LE>(InputSectionBase<ELF64LE> *);
+template bool elf::isDiscarded<ELF64BE>(InputSectionBase<ELF64BE> *);
+
+template class elf::InputSectionBase<ELF32LE>;
+template class elf::InputSectionBase<ELF32BE>;
+template class elf::InputSectionBase<ELF64LE>;
+template class elf::InputSectionBase<ELF64BE>;
+
+template class elf::InputSection<ELF32LE>;
+template class elf::InputSection<ELF32BE>;
+template class elf::InputSection<ELF64LE>;
+template class elf::InputSection<ELF64BE>;
+
+template class elf::SplitInputSection<ELF32LE>;
+template class elf::SplitInputSection<ELF32BE>;
+template class elf::SplitInputSection<ELF64LE>;
+template class elf::SplitInputSection<ELF64BE>;
+
+template class elf::EhInputSection<ELF32LE>;
+template class elf::EhInputSection<ELF32BE>;
+template class elf::EhInputSection<ELF64LE>;
+template class elf::EhInputSection<ELF64BE>;
+
+template class elf::MergeInputSection<ELF32LE>;
+template class elf::MergeInputSection<ELF32BE>;
+template class elf::MergeInputSection<ELF64LE>;
+template class elf::MergeInputSection<ELF64BE>;
+
+template class elf::MipsReginfoInputSection<ELF32LE>;
+template class elf::MipsReginfoInputSection<ELF32BE>;
+template class elf::MipsReginfoInputSection<ELF64LE>;
+template class elf::MipsReginfoInputSection<ELF64BE>;
+
+template class elf::MipsOptionsInputSection<ELF32LE>;
+template class elf::MipsOptionsInputSection<ELF32BE>;
+template class elf::MipsOptionsInputSection<ELF64LE>;
+template class elf::MipsOptionsInputSection<ELF64BE>;
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