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-rw-r--r--contrib/llvm-project/llvm/lib/ObjectYAML/ELFEmitter.cpp1461
1 files changed, 1461 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/ObjectYAML/ELFEmitter.cpp b/contrib/llvm-project/llvm/lib/ObjectYAML/ELFEmitter.cpp
new file mode 100644
index 000000000000..ee7d5f616a73
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/ObjectYAML/ELFEmitter.cpp
@@ -0,0 +1,1461 @@
+//===- yaml2elf - Convert YAML to a ELF object file -----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// The ELF component of yaml2obj.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/MC/StringTableBuilder.h"
+#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/ObjectYAML/ELFYAML.h"
+#include "llvm/ObjectYAML/yaml2obj.h"
+#include "llvm/Support/EndianStream.h"
+#include "llvm/Support/LEB128.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/WithColor.h"
+#include "llvm/Support/YAMLTraits.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+// This class is used to build up a contiguous binary blob while keeping
+// track of an offset in the output (which notionally begins at
+// `InitialOffset`).
+namespace {
+class ContiguousBlobAccumulator {
+ const uint64_t InitialOffset;
+ SmallVector<char, 128> Buf;
+ raw_svector_ostream OS;
+
+public:
+ ContiguousBlobAccumulator(uint64_t InitialOffset_)
+ : InitialOffset(InitialOffset_), Buf(), OS(Buf) {}
+
+ template <class Integer>
+ raw_ostream &getOSAndAlignedOffset(Integer &Offset, unsigned Align) {
+ Offset = padToAlignment(Align);
+ return OS;
+ }
+
+ /// \returns The new offset.
+ uint64_t padToAlignment(unsigned Align) {
+ if (Align == 0)
+ Align = 1;
+ uint64_t CurrentOffset = InitialOffset + OS.tell();
+ uint64_t AlignedOffset = alignTo(CurrentOffset, Align);
+ OS.write_zeros(AlignedOffset - CurrentOffset);
+ return AlignedOffset; // == CurrentOffset;
+ }
+
+ void writeBlobToStream(raw_ostream &Out) { Out << OS.str(); }
+};
+
+// Used to keep track of section and symbol names, so that in the YAML file
+// sections and symbols can be referenced by name instead of by index.
+class NameToIdxMap {
+ StringMap<unsigned> Map;
+
+public:
+ /// \Returns false if name is already present in the map.
+ bool addName(StringRef Name, unsigned Ndx) {
+ return Map.insert({Name, Ndx}).second;
+ }
+ /// \Returns false if name is not present in the map.
+ bool lookup(StringRef Name, unsigned &Idx) const {
+ auto I = Map.find(Name);
+ if (I == Map.end())
+ return false;
+ Idx = I->getValue();
+ return true;
+ }
+ /// Asserts if name is not present in the map.
+ unsigned get(StringRef Name) const {
+ unsigned Idx;
+ if (lookup(Name, Idx))
+ return Idx;
+ assert(false && "Expected section not found in index");
+ return 0;
+ }
+ unsigned size() const { return Map.size(); }
+};
+
+namespace {
+struct Fragment {
+ uint64_t Offset;
+ uint64_t Size;
+ uint32_t Type;
+ uint64_t AddrAlign;
+};
+} // namespace
+
+/// "Single point of truth" for the ELF file construction.
+/// TODO: This class still has a ways to go before it is truly a "single
+/// point of truth".
+template <class ELFT> class ELFState {
+ typedef typename ELFT::Ehdr Elf_Ehdr;
+ typedef typename ELFT::Phdr Elf_Phdr;
+ typedef typename ELFT::Shdr Elf_Shdr;
+ typedef typename ELFT::Sym Elf_Sym;
+ typedef typename ELFT::Rel Elf_Rel;
+ typedef typename ELFT::Rela Elf_Rela;
+ typedef typename ELFT::Relr Elf_Relr;
+ typedef typename ELFT::Dyn Elf_Dyn;
+ typedef typename ELFT::uint uintX_t;
+
+ enum class SymtabType { Static, Dynamic };
+
+ /// The future ".strtab" section.
+ StringTableBuilder DotStrtab{StringTableBuilder::ELF};
+
+ /// The future ".shstrtab" section.
+ StringTableBuilder DotShStrtab{StringTableBuilder::ELF};
+
+ /// The future ".dynstr" section.
+ StringTableBuilder DotDynstr{StringTableBuilder::ELF};
+
+ NameToIdxMap SN2I;
+ NameToIdxMap SymN2I;
+ NameToIdxMap DynSymN2I;
+ ELFYAML::Object &Doc;
+
+ bool HasError = false;
+ yaml::ErrorHandler ErrHandler;
+ void reportError(const Twine &Msg);
+
+ std::vector<Elf_Sym> toELFSymbols(ArrayRef<ELFYAML::Symbol> Symbols,
+ const StringTableBuilder &Strtab);
+ unsigned toSectionIndex(StringRef S, StringRef LocSec, StringRef LocSym = "");
+ unsigned toSymbolIndex(StringRef S, StringRef LocSec, bool IsDynamic);
+
+ void buildSectionIndex();
+ void buildSymbolIndexes();
+ void initProgramHeaders(std::vector<Elf_Phdr> &PHeaders);
+ bool initImplicitHeader(ContiguousBlobAccumulator &CBA, Elf_Shdr &Header,
+ StringRef SecName, ELFYAML::Section *YAMLSec);
+ void initSectionHeaders(std::vector<Elf_Shdr> &SHeaders,
+ ContiguousBlobAccumulator &CBA);
+ void initSymtabSectionHeader(Elf_Shdr &SHeader, SymtabType STType,
+ ContiguousBlobAccumulator &CBA,
+ ELFYAML::Section *YAMLSec);
+ void initStrtabSectionHeader(Elf_Shdr &SHeader, StringRef Name,
+ StringTableBuilder &STB,
+ ContiguousBlobAccumulator &CBA,
+ ELFYAML::Section *YAMLSec);
+ void setProgramHeaderLayout(std::vector<Elf_Phdr> &PHeaders,
+ std::vector<Elf_Shdr> &SHeaders);
+
+ std::vector<Fragment>
+ getPhdrFragments(const ELFYAML::ProgramHeader &Phdr,
+ ArrayRef<typename ELFT::Shdr> SHeaders);
+
+ void finalizeStrings();
+ void writeELFHeader(ContiguousBlobAccumulator &CBA, raw_ostream &OS);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::RawContentSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::RelocationSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::RelrSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader, const ELFYAML::Group &Group,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::SymtabShndxSection &Shndx,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::SymverSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::VerneedSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::VerdefSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::MipsABIFlags &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::DynamicSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::StackSizesSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::HashSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::AddrsigSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::NoteSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::GnuHashSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::LinkerOptionsSection &Section,
+ ContiguousBlobAccumulator &CBA);
+ void writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::DependentLibrariesSection &Section,
+ ContiguousBlobAccumulator &CBA);
+
+ void writeFill(ELFYAML::Fill &Fill, ContiguousBlobAccumulator &CBA);
+
+ ELFState(ELFYAML::Object &D, yaml::ErrorHandler EH);
+
+public:
+ static bool writeELF(raw_ostream &OS, ELFYAML::Object &Doc,
+ yaml::ErrorHandler EH);
+};
+} // end anonymous namespace
+
+template <class T> static size_t arrayDataSize(ArrayRef<T> A) {
+ return A.size() * sizeof(T);
+}
+
+template <class T> static void writeArrayData(raw_ostream &OS, ArrayRef<T> A) {
+ OS.write((const char *)A.data(), arrayDataSize(A));
+}
+
+template <class T> static void zero(T &Obj) { memset(&Obj, 0, sizeof(Obj)); }
+
+template <class ELFT>
+ELFState<ELFT>::ELFState(ELFYAML::Object &D, yaml::ErrorHandler EH)
+ : Doc(D), ErrHandler(EH) {
+ std::vector<ELFYAML::Section *> Sections = Doc.getSections();
+ StringSet<> DocSections;
+ for (const ELFYAML::Section *Sec : Sections)
+ if (!Sec->Name.empty())
+ DocSections.insert(Sec->Name);
+
+ // Insert SHT_NULL section implicitly when it is not defined in YAML.
+ if (Sections.empty() || Sections.front()->Type != ELF::SHT_NULL)
+ Doc.Chunks.insert(
+ Doc.Chunks.begin(),
+ std::make_unique<ELFYAML::Section>(
+ ELFYAML::Chunk::ChunkKind::RawContent, /*IsImplicit=*/true));
+
+ std::vector<StringRef> ImplicitSections;
+ if (Doc.Symbols)
+ ImplicitSections.push_back(".symtab");
+ ImplicitSections.insert(ImplicitSections.end(), {".strtab", ".shstrtab"});
+
+ if (Doc.DynamicSymbols)
+ ImplicitSections.insert(ImplicitSections.end(), {".dynsym", ".dynstr"});
+
+ // Insert placeholders for implicit sections that are not
+ // defined explicitly in YAML.
+ for (StringRef SecName : ImplicitSections) {
+ if (DocSections.count(SecName))
+ continue;
+
+ std::unique_ptr<ELFYAML::Chunk> Sec = std::make_unique<ELFYAML::Section>(
+ ELFYAML::Chunk::ChunkKind::RawContent, true /*IsImplicit*/);
+ Sec->Name = SecName;
+ Doc.Chunks.push_back(std::move(Sec));
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeELFHeader(ContiguousBlobAccumulator &CBA, raw_ostream &OS) {
+ using namespace llvm::ELF;
+
+ Elf_Ehdr Header;
+ zero(Header);
+ Header.e_ident[EI_MAG0] = 0x7f;
+ Header.e_ident[EI_MAG1] = 'E';
+ Header.e_ident[EI_MAG2] = 'L';
+ Header.e_ident[EI_MAG3] = 'F';
+ Header.e_ident[EI_CLASS] = ELFT::Is64Bits ? ELFCLASS64 : ELFCLASS32;
+ Header.e_ident[EI_DATA] = Doc.Header.Data;
+ Header.e_ident[EI_VERSION] = EV_CURRENT;
+ Header.e_ident[EI_OSABI] = Doc.Header.OSABI;
+ Header.e_ident[EI_ABIVERSION] = Doc.Header.ABIVersion;
+ Header.e_type = Doc.Header.Type;
+ Header.e_machine = Doc.Header.Machine;
+ Header.e_version = EV_CURRENT;
+ Header.e_entry = Doc.Header.Entry;
+ Header.e_phoff = Doc.ProgramHeaders.size() ? sizeof(Header) : 0;
+ Header.e_flags = Doc.Header.Flags;
+ Header.e_ehsize = sizeof(Elf_Ehdr);
+ Header.e_phentsize = Doc.ProgramHeaders.size() ? sizeof(Elf_Phdr) : 0;
+ Header.e_phnum = Doc.ProgramHeaders.size();
+
+ Header.e_shentsize =
+ Doc.Header.SHEntSize ? (uint16_t)*Doc.Header.SHEntSize : sizeof(Elf_Shdr);
+ // Immediately following the ELF header and program headers.
+ // Align the start of the section header and write the ELF header.
+ uint64_t SHOff;
+ CBA.getOSAndAlignedOffset(SHOff, sizeof(typename ELFT::uint));
+ Header.e_shoff =
+ Doc.Header.SHOff ? typename ELFT::uint(*Doc.Header.SHOff) : SHOff;
+ Header.e_shnum =
+ Doc.Header.SHNum ? (uint16_t)*Doc.Header.SHNum : Doc.getSections().size();
+ Header.e_shstrndx = Doc.Header.SHStrNdx ? (uint16_t)*Doc.Header.SHStrNdx
+ : SN2I.get(".shstrtab");
+
+ OS.write((const char *)&Header, sizeof(Header));
+}
+
+template <class ELFT>
+void ELFState<ELFT>::initProgramHeaders(std::vector<Elf_Phdr> &PHeaders) {
+ for (const auto &YamlPhdr : Doc.ProgramHeaders) {
+ Elf_Phdr Phdr;
+ Phdr.p_type = YamlPhdr.Type;
+ Phdr.p_flags = YamlPhdr.Flags;
+ Phdr.p_vaddr = YamlPhdr.VAddr;
+ Phdr.p_paddr = YamlPhdr.PAddr;
+ PHeaders.push_back(Phdr);
+ }
+}
+
+template <class ELFT>
+unsigned ELFState<ELFT>::toSectionIndex(StringRef S, StringRef LocSec,
+ StringRef LocSym) {
+ unsigned Index;
+ if (SN2I.lookup(S, Index) || to_integer(S, Index))
+ return Index;
+
+ assert(LocSec.empty() || LocSym.empty());
+ if (!LocSym.empty())
+ reportError("unknown section referenced: '" + S + "' by YAML symbol '" +
+ LocSym + "'");
+ else
+ reportError("unknown section referenced: '" + S + "' by YAML section '" +
+ LocSec + "'");
+ return 0;
+}
+
+template <class ELFT>
+unsigned ELFState<ELFT>::toSymbolIndex(StringRef S, StringRef LocSec,
+ bool IsDynamic) {
+ const NameToIdxMap &SymMap = IsDynamic ? DynSymN2I : SymN2I;
+ unsigned Index;
+ // Here we try to look up S in the symbol table. If it is not there,
+ // treat its value as a symbol index.
+ if (!SymMap.lookup(S, Index) && !to_integer(S, Index)) {
+ reportError("unknown symbol referenced: '" + S + "' by YAML section '" +
+ LocSec + "'");
+ return 0;
+ }
+ return Index;
+}
+
+template <class ELFT>
+static void overrideFields(ELFYAML::Section *From, typename ELFT::Shdr &To) {
+ if (!From)
+ return;
+ if (From->ShFlags)
+ To.sh_flags = *From->ShFlags;
+ if (From->ShName)
+ To.sh_name = *From->ShName;
+ if (From->ShOffset)
+ To.sh_offset = *From->ShOffset;
+ if (From->ShSize)
+ To.sh_size = *From->ShSize;
+}
+
+template <class ELFT>
+bool ELFState<ELFT>::initImplicitHeader(ContiguousBlobAccumulator &CBA,
+ Elf_Shdr &Header, StringRef SecName,
+ ELFYAML::Section *YAMLSec) {
+ // Check if the header was already initialized.
+ if (Header.sh_offset)
+ return false;
+
+ if (SecName == ".symtab")
+ initSymtabSectionHeader(Header, SymtabType::Static, CBA, YAMLSec);
+ else if (SecName == ".strtab")
+ initStrtabSectionHeader(Header, SecName, DotStrtab, CBA, YAMLSec);
+ else if (SecName == ".shstrtab")
+ initStrtabSectionHeader(Header, SecName, DotShStrtab, CBA, YAMLSec);
+ else if (SecName == ".dynsym")
+ initSymtabSectionHeader(Header, SymtabType::Dynamic, CBA, YAMLSec);
+ else if (SecName == ".dynstr")
+ initStrtabSectionHeader(Header, SecName, DotDynstr, CBA, YAMLSec);
+ else
+ return false;
+
+ // Override section fields if requested.
+ overrideFields<ELFT>(YAMLSec, Header);
+ return true;
+}
+
+StringRef llvm::ELFYAML::dropUniqueSuffix(StringRef S) {
+ size_t SuffixPos = S.rfind(" [");
+ if (SuffixPos == StringRef::npos)
+ return S;
+ return S.substr(0, SuffixPos);
+}
+
+template <class ELFT>
+void ELFState<ELFT>::initSectionHeaders(std::vector<Elf_Shdr> &SHeaders,
+ ContiguousBlobAccumulator &CBA) {
+ // Ensure SHN_UNDEF entry is present. An all-zero section header is a
+ // valid SHN_UNDEF entry since SHT_NULL == 0.
+ SHeaders.resize(Doc.getSections().size());
+
+ size_t SecNdx = -1;
+ for (const std::unique_ptr<ELFYAML::Chunk> &D : Doc.Chunks) {
+ if (auto S = dyn_cast<ELFYAML::Fill>(D.get())) {
+ writeFill(*S, CBA);
+ continue;
+ }
+
+ ++SecNdx;
+ ELFYAML::Section *Sec = cast<ELFYAML::Section>(D.get());
+ if (SecNdx == 0 && Sec->IsImplicit)
+ continue;
+
+ // We have a few sections like string or symbol tables that are usually
+ // added implicitly to the end. However, if they are explicitly specified
+ // in the YAML, we need to write them here. This ensures the file offset
+ // remains correct.
+ Elf_Shdr &SHeader = SHeaders[SecNdx];
+ if (initImplicitHeader(CBA, SHeader, Sec->Name,
+ Sec->IsImplicit ? nullptr : Sec))
+ continue;
+
+ assert(Sec && "It can't be null unless it is an implicit section. But all "
+ "implicit sections should already have been handled above.");
+
+ SHeader.sh_name =
+ DotShStrtab.getOffset(ELFYAML::dropUniqueSuffix(Sec->Name));
+ SHeader.sh_type = Sec->Type;
+ if (Sec->Flags)
+ SHeader.sh_flags = *Sec->Flags;
+ SHeader.sh_addr = Sec->Address;
+ SHeader.sh_addralign = Sec->AddressAlign;
+
+ if (!Sec->Link.empty())
+ SHeader.sh_link = toSectionIndex(Sec->Link, Sec->Name);
+
+ if (SecNdx == 0) {
+ if (auto RawSec = dyn_cast<ELFYAML::RawContentSection>(Sec)) {
+ // We do not write any content for special SHN_UNDEF section.
+ if (RawSec->Size)
+ SHeader.sh_size = *RawSec->Size;
+ if (RawSec->Info)
+ SHeader.sh_info = *RawSec->Info;
+ }
+ if (Sec->EntSize)
+ SHeader.sh_entsize = *Sec->EntSize;
+ } else if (auto S = dyn_cast<ELFYAML::RawContentSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::SymtabShndxSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::RelocationSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::RelrSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::Group>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::MipsABIFlags>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::NoBitsSection>(Sec)) {
+ SHeader.sh_entsize = 0;
+ SHeader.sh_size = S->Size;
+ // SHT_NOBITS section does not have content
+ // so just to setup the section offset.
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ } else if (auto S = dyn_cast<ELFYAML::DynamicSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::SymverSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::VerneedSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::VerdefSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::StackSizesSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::HashSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::AddrsigSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::LinkerOptionsSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::NoteSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::GnuHashSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else if (auto S = dyn_cast<ELFYAML::DependentLibrariesSection>(Sec)) {
+ writeSectionContent(SHeader, *S, CBA);
+ } else {
+ llvm_unreachable("Unknown section type");
+ }
+
+ // Override section fields if requested.
+ overrideFields<ELFT>(Sec, SHeader);
+ }
+}
+
+static size_t findFirstNonGlobal(ArrayRef<ELFYAML::Symbol> Symbols) {
+ for (size_t I = 0; I < Symbols.size(); ++I)
+ if (Symbols[I].Binding.value != ELF::STB_LOCAL)
+ return I;
+ return Symbols.size();
+}
+
+static uint64_t writeContent(raw_ostream &OS,
+ const Optional<yaml::BinaryRef> &Content,
+ const Optional<llvm::yaml::Hex64> &Size) {
+ size_t ContentSize = 0;
+ if (Content) {
+ Content->writeAsBinary(OS);
+ ContentSize = Content->binary_size();
+ }
+
+ if (!Size)
+ return ContentSize;
+
+ OS.write_zeros(*Size - ContentSize);
+ return *Size;
+}
+
+template <class ELFT>
+std::vector<typename ELFT::Sym>
+ELFState<ELFT>::toELFSymbols(ArrayRef<ELFYAML::Symbol> Symbols,
+ const StringTableBuilder &Strtab) {
+ std::vector<Elf_Sym> Ret;
+ Ret.resize(Symbols.size() + 1);
+
+ size_t I = 0;
+ for (const ELFYAML::Symbol &Sym : Symbols) {
+ Elf_Sym &Symbol = Ret[++I];
+
+ // If NameIndex, which contains the name offset, is explicitly specified, we
+ // use it. This is useful for preparing broken objects. Otherwise, we add
+ // the specified Name to the string table builder to get its offset.
+ if (Sym.NameIndex)
+ Symbol.st_name = *Sym.NameIndex;
+ else if (!Sym.Name.empty())
+ Symbol.st_name = Strtab.getOffset(ELFYAML::dropUniqueSuffix(Sym.Name));
+
+ Symbol.setBindingAndType(Sym.Binding, Sym.Type);
+ if (!Sym.Section.empty())
+ Symbol.st_shndx = toSectionIndex(Sym.Section, "", Sym.Name);
+ else if (Sym.Index)
+ Symbol.st_shndx = *Sym.Index;
+
+ Symbol.st_value = Sym.Value;
+ Symbol.st_other = Sym.Other ? *Sym.Other : 0;
+ Symbol.st_size = Sym.Size;
+ }
+
+ return Ret;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::initSymtabSectionHeader(Elf_Shdr &SHeader,
+ SymtabType STType,
+ ContiguousBlobAccumulator &CBA,
+ ELFYAML::Section *YAMLSec) {
+
+ bool IsStatic = STType == SymtabType::Static;
+ ArrayRef<ELFYAML::Symbol> Symbols;
+ if (IsStatic && Doc.Symbols)
+ Symbols = *Doc.Symbols;
+ else if (!IsStatic && Doc.DynamicSymbols)
+ Symbols = *Doc.DynamicSymbols;
+
+ ELFYAML::RawContentSection *RawSec =
+ dyn_cast_or_null<ELFYAML::RawContentSection>(YAMLSec);
+ if (RawSec && (RawSec->Content || RawSec->Size)) {
+ bool HasSymbolsDescription =
+ (IsStatic && Doc.Symbols) || (!IsStatic && Doc.DynamicSymbols);
+ if (HasSymbolsDescription) {
+ StringRef Property = (IsStatic ? "`Symbols`" : "`DynamicSymbols`");
+ if (RawSec->Content)
+ reportError("cannot specify both `Content` and " + Property +
+ " for symbol table section '" + RawSec->Name + "'");
+ if (RawSec->Size)
+ reportError("cannot specify both `Size` and " + Property +
+ " for symbol table section '" + RawSec->Name + "'");
+ return;
+ }
+ }
+
+ zero(SHeader);
+ SHeader.sh_name = DotShStrtab.getOffset(IsStatic ? ".symtab" : ".dynsym");
+
+ if (YAMLSec)
+ SHeader.sh_type = YAMLSec->Type;
+ else
+ SHeader.sh_type = IsStatic ? ELF::SHT_SYMTAB : ELF::SHT_DYNSYM;
+
+ if (RawSec && !RawSec->Link.empty()) {
+ // If the Link field is explicitly defined in the document,
+ // we should use it.
+ SHeader.sh_link = toSectionIndex(RawSec->Link, RawSec->Name);
+ } else {
+ // When we describe the .dynsym section in the document explicitly, it is
+ // allowed to omit the "DynamicSymbols" tag. In this case .dynstr is not
+ // added implicitly and we should be able to leave the Link zeroed if
+ // .dynstr is not defined.
+ unsigned Link = 0;
+ if (IsStatic)
+ Link = SN2I.get(".strtab");
+ else
+ SN2I.lookup(".dynstr", Link);
+ SHeader.sh_link = Link;
+ }
+
+ if (YAMLSec && YAMLSec->Flags)
+ SHeader.sh_flags = *YAMLSec->Flags;
+ else if (!IsStatic)
+ SHeader.sh_flags = ELF::SHF_ALLOC;
+
+ // If the symbol table section is explicitly described in the YAML
+ // then we should set the fields requested.
+ SHeader.sh_info = (RawSec && RawSec->Info) ? (unsigned)(*RawSec->Info)
+ : findFirstNonGlobal(Symbols) + 1;
+ SHeader.sh_entsize = (YAMLSec && YAMLSec->EntSize)
+ ? (uint64_t)(*YAMLSec->EntSize)
+ : sizeof(Elf_Sym);
+ SHeader.sh_addralign = YAMLSec ? (uint64_t)YAMLSec->AddressAlign : 8;
+ SHeader.sh_addr = YAMLSec ? (uint64_t)YAMLSec->Address : 0;
+
+ auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ if (RawSec && (RawSec->Content || RawSec->Size)) {
+ assert(Symbols.empty());
+ SHeader.sh_size = writeContent(OS, RawSec->Content, RawSec->Size);
+ return;
+ }
+
+ std::vector<Elf_Sym> Syms =
+ toELFSymbols(Symbols, IsStatic ? DotStrtab : DotDynstr);
+ writeArrayData(OS, makeArrayRef(Syms));
+ SHeader.sh_size = arrayDataSize(makeArrayRef(Syms));
+}
+
+template <class ELFT>
+void ELFState<ELFT>::initStrtabSectionHeader(Elf_Shdr &SHeader, StringRef Name,
+ StringTableBuilder &STB,
+ ContiguousBlobAccumulator &CBA,
+ ELFYAML::Section *YAMLSec) {
+ zero(SHeader);
+ SHeader.sh_name = DotShStrtab.getOffset(Name);
+ SHeader.sh_type = YAMLSec ? YAMLSec->Type : ELF::SHT_STRTAB;
+ SHeader.sh_addralign = YAMLSec ? (uint64_t)YAMLSec->AddressAlign : 1;
+
+ ELFYAML::RawContentSection *RawSec =
+ dyn_cast_or_null<ELFYAML::RawContentSection>(YAMLSec);
+
+ auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ if (RawSec && (RawSec->Content || RawSec->Size)) {
+ SHeader.sh_size = writeContent(OS, RawSec->Content, RawSec->Size);
+ } else {
+ STB.write(OS);
+ SHeader.sh_size = STB.getSize();
+ }
+
+ if (YAMLSec && YAMLSec->EntSize)
+ SHeader.sh_entsize = *YAMLSec->EntSize;
+
+ if (RawSec && RawSec->Info)
+ SHeader.sh_info = *RawSec->Info;
+
+ if (YAMLSec && YAMLSec->Flags)
+ SHeader.sh_flags = *YAMLSec->Flags;
+ else if (Name == ".dynstr")
+ SHeader.sh_flags = ELF::SHF_ALLOC;
+
+ // If the section is explicitly described in the YAML
+ // then we want to use its section address.
+ if (YAMLSec)
+ SHeader.sh_addr = YAMLSec->Address;
+}
+
+template <class ELFT> void ELFState<ELFT>::reportError(const Twine &Msg) {
+ ErrHandler(Msg);
+ HasError = true;
+}
+
+template <class ELFT>
+std::vector<Fragment>
+ELFState<ELFT>::getPhdrFragments(const ELFYAML::ProgramHeader &Phdr,
+ ArrayRef<typename ELFT::Shdr> SHeaders) {
+ DenseMap<StringRef, ELFYAML::Fill *> NameToFill;
+ for (const std::unique_ptr<ELFYAML::Chunk> &D : Doc.Chunks)
+ if (auto S = dyn_cast<ELFYAML::Fill>(D.get()))
+ NameToFill[S->Name] = S;
+
+ std::vector<Fragment> Ret;
+ for (const ELFYAML::SectionName &SecName : Phdr.Sections) {
+ unsigned Index;
+ if (SN2I.lookup(SecName.Section, Index)) {
+ const typename ELFT::Shdr &H = SHeaders[Index];
+ Ret.push_back({H.sh_offset, H.sh_size, H.sh_type, H.sh_addralign});
+ continue;
+ }
+
+ if (ELFYAML::Fill *Fill = NameToFill.lookup(SecName.Section)) {
+ Ret.push_back({Fill->ShOffset, Fill->Size, llvm::ELF::SHT_PROGBITS,
+ /*ShAddrAlign=*/1});
+ continue;
+ }
+
+ reportError("unknown section or fill referenced: '" + SecName.Section +
+ "' by program header");
+ }
+
+ return Ret;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::setProgramHeaderLayout(std::vector<Elf_Phdr> &PHeaders,
+ std::vector<Elf_Shdr> &SHeaders) {
+ uint32_t PhdrIdx = 0;
+ for (auto &YamlPhdr : Doc.ProgramHeaders) {
+ Elf_Phdr &PHeader = PHeaders[PhdrIdx++];
+ std::vector<Fragment> Fragments = getPhdrFragments(YamlPhdr, SHeaders);
+
+ if (YamlPhdr.Offset) {
+ PHeader.p_offset = *YamlPhdr.Offset;
+ } else {
+ if (YamlPhdr.Sections.size())
+ PHeader.p_offset = UINT32_MAX;
+ else
+ PHeader.p_offset = 0;
+
+ // Find the minimum offset for the program header.
+ for (const Fragment &F : Fragments)
+ PHeader.p_offset = std::min((uint64_t)PHeader.p_offset, F.Offset);
+ }
+
+ // Find the maximum offset of the end of a section in order to set p_filesz
+ // and p_memsz. When setting p_filesz, trailing SHT_NOBITS sections are not
+ // counted.
+ uint64_t FileOffset = PHeader.p_offset, MemOffset = PHeader.p_offset;
+ for (const Fragment &F : Fragments) {
+ uint64_t End = F.Offset + F.Size;
+ MemOffset = std::max(MemOffset, End);
+
+ if (F.Type != llvm::ELF::SHT_NOBITS)
+ FileOffset = std::max(FileOffset, End);
+ }
+
+ // Set the file size and the memory size if not set explicitly.
+ PHeader.p_filesz = YamlPhdr.FileSize ? uint64_t(*YamlPhdr.FileSize)
+ : FileOffset - PHeader.p_offset;
+ PHeader.p_memsz = YamlPhdr.MemSize ? uint64_t(*YamlPhdr.MemSize)
+ : MemOffset - PHeader.p_offset;
+
+ if (YamlPhdr.Align) {
+ PHeader.p_align = *YamlPhdr.Align;
+ } else {
+ // Set the alignment of the segment to be the maximum alignment of the
+ // sections so that by default the segment has a valid and sensible
+ // alignment.
+ PHeader.p_align = 1;
+ for (const Fragment &F : Fragments)
+ PHeader.p_align = std::max((uint64_t)PHeader.p_align, F.AddrAlign);
+ }
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::RawContentSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
+
+ if (Section.EntSize)
+ SHeader.sh_entsize = *Section.EntSize;
+
+ if (Section.Info)
+ SHeader.sh_info = *Section.Info;
+}
+
+static bool isMips64EL(const ELFYAML::Object &Doc) {
+ return Doc.Header.Machine == ELFYAML::ELF_EM(llvm::ELF::EM_MIPS) &&
+ Doc.Header.Class == ELFYAML::ELF_ELFCLASS(ELF::ELFCLASS64) &&
+ Doc.Header.Data == ELFYAML::ELF_ELFDATA(ELF::ELFDATA2LSB);
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::RelocationSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ assert((Section.Type == llvm::ELF::SHT_REL ||
+ Section.Type == llvm::ELF::SHT_RELA) &&
+ "Section type is not SHT_REL nor SHT_RELA");
+
+ bool IsRela = Section.Type == llvm::ELF::SHT_RELA;
+ SHeader.sh_entsize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel);
+ SHeader.sh_size = SHeader.sh_entsize * Section.Relocations.size();
+
+ // For relocation section set link to .symtab by default.
+ unsigned Link = 0;
+ if (Section.Link.empty() && SN2I.lookup(".symtab", Link))
+ SHeader.sh_link = Link;
+
+ if (!Section.RelocatableSec.empty())
+ SHeader.sh_info = toSectionIndex(Section.RelocatableSec, Section.Name);
+
+ auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ for (const auto &Rel : Section.Relocations) {
+ unsigned SymIdx = Rel.Symbol ? toSymbolIndex(*Rel.Symbol, Section.Name,
+ Section.Link == ".dynsym")
+ : 0;
+ if (IsRela) {
+ Elf_Rela REntry;
+ zero(REntry);
+ REntry.r_offset = Rel.Offset;
+ REntry.r_addend = Rel.Addend;
+ REntry.setSymbolAndType(SymIdx, Rel.Type, isMips64EL(Doc));
+ OS.write((const char *)&REntry, sizeof(REntry));
+ } else {
+ Elf_Rel REntry;
+ zero(REntry);
+ REntry.r_offset = Rel.Offset;
+ REntry.setSymbolAndType(SymIdx, Rel.Type, isMips64EL(Doc));
+ OS.write((const char *)&REntry, sizeof(REntry));
+ }
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::RelrSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ SHeader.sh_entsize =
+ Section.EntSize ? uint64_t(*Section.EntSize) : sizeof(Elf_Relr);
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ if (!Section.Entries)
+ return;
+
+ for (llvm::yaml::Hex64 E : *Section.Entries) {
+ if (!ELFT::Is64Bits && E > UINT32_MAX)
+ reportError(Section.Name + ": the value is too large for 32-bits: 0x" +
+ Twine::utohexstr(E));
+ support::endian::write<uintX_t>(OS, E, ELFT::TargetEndianness);
+ }
+
+ SHeader.sh_size = sizeof(uintX_t) * Section.Entries->size();
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::SymtabShndxSection &Shndx,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ for (uint32_t E : Shndx.Entries)
+ support::endian::write<uint32_t>(OS, E, ELFT::TargetEndianness);
+
+ SHeader.sh_entsize = Shndx.EntSize ? (uint64_t)*Shndx.EntSize : 4;
+ SHeader.sh_size = Shndx.Entries.size() * SHeader.sh_entsize;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::Group &Section,
+ ContiguousBlobAccumulator &CBA) {
+ assert(Section.Type == llvm::ELF::SHT_GROUP &&
+ "Section type is not SHT_GROUP");
+
+ unsigned Link = 0;
+ if (Section.Link.empty() && SN2I.lookup(".symtab", Link))
+ SHeader.sh_link = Link;
+
+ SHeader.sh_entsize = 4;
+ SHeader.sh_size = SHeader.sh_entsize * Section.Members.size();
+
+ if (Section.Signature)
+ SHeader.sh_info =
+ toSymbolIndex(*Section.Signature, Section.Name, /*IsDynamic=*/false);
+
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ for (const ELFYAML::SectionOrType &Member : Section.Members) {
+ unsigned int SectionIndex = 0;
+ if (Member.sectionNameOrType == "GRP_COMDAT")
+ SectionIndex = llvm::ELF::GRP_COMDAT;
+ else
+ SectionIndex = toSectionIndex(Member.sectionNameOrType, Section.Name);
+ support::endian::write<uint32_t>(OS, SectionIndex, ELFT::TargetEndianness);
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::SymverSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ for (uint16_t Version : Section.Entries)
+ support::endian::write<uint16_t>(OS, Version, ELFT::TargetEndianness);
+
+ SHeader.sh_entsize = Section.EntSize ? (uint64_t)*Section.EntSize : 2;
+ SHeader.sh_size = Section.Entries.size() * SHeader.sh_entsize;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::StackSizesSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ if (Section.Content || Section.Size) {
+ SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
+ return;
+ }
+
+ for (const ELFYAML::StackSizeEntry &E : *Section.Entries) {
+ support::endian::write<uintX_t>(OS, E.Address, ELFT::TargetEndianness);
+ SHeader.sh_size += sizeof(uintX_t) + encodeULEB128(E.Size, OS);
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::LinkerOptionsSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ if (!Section.Options)
+ return;
+
+ for (const ELFYAML::LinkerOption &LO : *Section.Options) {
+ OS.write(LO.Key.data(), LO.Key.size());
+ OS.write('\0');
+ OS.write(LO.Value.data(), LO.Value.size());
+ OS.write('\0');
+ SHeader.sh_size += (LO.Key.size() + LO.Value.size() + 2);
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(
+ Elf_Shdr &SHeader, const ELFYAML::DependentLibrariesSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ if (!Section.Libs)
+ return;
+
+ for (StringRef Lib : *Section.Libs) {
+ OS.write(Lib.data(), Lib.size());
+ OS.write('\0');
+ SHeader.sh_size += Lib.size() + 1;
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::HashSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ unsigned Link = 0;
+ if (Section.Link.empty() && SN2I.lookup(".dynsym", Link))
+ SHeader.sh_link = Link;
+
+ if (Section.Content || Section.Size) {
+ SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
+ return;
+ }
+
+ support::endian::write<uint32_t>(OS, Section.Bucket->size(),
+ ELFT::TargetEndianness);
+ support::endian::write<uint32_t>(OS, Section.Chain->size(),
+ ELFT::TargetEndianness);
+ for (uint32_t Val : *Section.Bucket)
+ support::endian::write<uint32_t>(OS, Val, ELFT::TargetEndianness);
+ for (uint32_t Val : *Section.Chain)
+ support::endian::write<uint32_t>(OS, Val, ELFT::TargetEndianness);
+
+ SHeader.sh_size = (2 + Section.Bucket->size() + Section.Chain->size()) * 4;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::VerdefSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ typedef typename ELFT::Verdef Elf_Verdef;
+ typedef typename ELFT::Verdaux Elf_Verdaux;
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ SHeader.sh_info = Section.Info;
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ if (!Section.Entries)
+ return;
+
+ uint64_t AuxCnt = 0;
+ for (size_t I = 0; I < Section.Entries->size(); ++I) {
+ const ELFYAML::VerdefEntry &E = (*Section.Entries)[I];
+
+ Elf_Verdef VerDef;
+ VerDef.vd_version = E.Version;
+ VerDef.vd_flags = E.Flags;
+ VerDef.vd_ndx = E.VersionNdx;
+ VerDef.vd_hash = E.Hash;
+ VerDef.vd_aux = sizeof(Elf_Verdef);
+ VerDef.vd_cnt = E.VerNames.size();
+ if (I == Section.Entries->size() - 1)
+ VerDef.vd_next = 0;
+ else
+ VerDef.vd_next =
+ sizeof(Elf_Verdef) + E.VerNames.size() * sizeof(Elf_Verdaux);
+ OS.write((const char *)&VerDef, sizeof(Elf_Verdef));
+
+ for (size_t J = 0; J < E.VerNames.size(); ++J, ++AuxCnt) {
+ Elf_Verdaux VernAux;
+ VernAux.vda_name = DotDynstr.getOffset(E.VerNames[J]);
+ if (J == E.VerNames.size() - 1)
+ VernAux.vda_next = 0;
+ else
+ VernAux.vda_next = sizeof(Elf_Verdaux);
+ OS.write((const char *)&VernAux, sizeof(Elf_Verdaux));
+ }
+ }
+
+ SHeader.sh_size = Section.Entries->size() * sizeof(Elf_Verdef) +
+ AuxCnt * sizeof(Elf_Verdaux);
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::VerneedSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ typedef typename ELFT::Verneed Elf_Verneed;
+ typedef typename ELFT::Vernaux Elf_Vernaux;
+
+ auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ SHeader.sh_info = Section.Info;
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ if (!Section.VerneedV)
+ return;
+
+ uint64_t AuxCnt = 0;
+ for (size_t I = 0; I < Section.VerneedV->size(); ++I) {
+ const ELFYAML::VerneedEntry &VE = (*Section.VerneedV)[I];
+
+ Elf_Verneed VerNeed;
+ VerNeed.vn_version = VE.Version;
+ VerNeed.vn_file = DotDynstr.getOffset(VE.File);
+ if (I == Section.VerneedV->size() - 1)
+ VerNeed.vn_next = 0;
+ else
+ VerNeed.vn_next =
+ sizeof(Elf_Verneed) + VE.AuxV.size() * sizeof(Elf_Vernaux);
+ VerNeed.vn_cnt = VE.AuxV.size();
+ VerNeed.vn_aux = sizeof(Elf_Verneed);
+ OS.write((const char *)&VerNeed, sizeof(Elf_Verneed));
+
+ for (size_t J = 0; J < VE.AuxV.size(); ++J, ++AuxCnt) {
+ const ELFYAML::VernauxEntry &VAuxE = VE.AuxV[J];
+
+ Elf_Vernaux VernAux;
+ VernAux.vna_hash = VAuxE.Hash;
+ VernAux.vna_flags = VAuxE.Flags;
+ VernAux.vna_other = VAuxE.Other;
+ VernAux.vna_name = DotDynstr.getOffset(VAuxE.Name);
+ if (J == VE.AuxV.size() - 1)
+ VernAux.vna_next = 0;
+ else
+ VernAux.vna_next = sizeof(Elf_Vernaux);
+ OS.write((const char *)&VernAux, sizeof(Elf_Vernaux));
+ }
+ }
+
+ SHeader.sh_size = Section.VerneedV->size() * sizeof(Elf_Verneed) +
+ AuxCnt * sizeof(Elf_Vernaux);
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::MipsABIFlags &Section,
+ ContiguousBlobAccumulator &CBA) {
+ assert(Section.Type == llvm::ELF::SHT_MIPS_ABIFLAGS &&
+ "Section type is not SHT_MIPS_ABIFLAGS");
+
+ object::Elf_Mips_ABIFlags<ELFT> Flags;
+ zero(Flags);
+ SHeader.sh_entsize = sizeof(Flags);
+ SHeader.sh_size = SHeader.sh_entsize;
+
+ auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ Flags.version = Section.Version;
+ Flags.isa_level = Section.ISALevel;
+ Flags.isa_rev = Section.ISARevision;
+ Flags.gpr_size = Section.GPRSize;
+ Flags.cpr1_size = Section.CPR1Size;
+ Flags.cpr2_size = Section.CPR2Size;
+ Flags.fp_abi = Section.FpABI;
+ Flags.isa_ext = Section.ISAExtension;
+ Flags.ases = Section.ASEs;
+ Flags.flags1 = Section.Flags1;
+ Flags.flags2 = Section.Flags2;
+ OS.write((const char *)&Flags, sizeof(Flags));
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::DynamicSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ assert(Section.Type == llvm::ELF::SHT_DYNAMIC &&
+ "Section type is not SHT_DYNAMIC");
+
+ if (!Section.Entries.empty() && Section.Content)
+ reportError("cannot specify both raw content and explicit entries "
+ "for dynamic section '" +
+ Section.Name + "'");
+
+ if (Section.Content)
+ SHeader.sh_size = Section.Content->binary_size();
+ else
+ SHeader.sh_size = 2 * sizeof(uintX_t) * Section.Entries.size();
+ if (Section.EntSize)
+ SHeader.sh_entsize = *Section.EntSize;
+ else
+ SHeader.sh_entsize = sizeof(Elf_Dyn);
+
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ for (const ELFYAML::DynamicEntry &DE : Section.Entries) {
+ support::endian::write<uintX_t>(OS, DE.Tag, ELFT::TargetEndianness);
+ support::endian::write<uintX_t>(OS, DE.Val, ELFT::TargetEndianness);
+ }
+ if (Section.Content)
+ Section.Content->writeAsBinary(OS);
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::AddrsigSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ unsigned Link = 0;
+ if (Section.Link.empty() && SN2I.lookup(".symtab", Link))
+ SHeader.sh_link = Link;
+
+ if (Section.Content || Section.Size) {
+ SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
+ return;
+ }
+
+ for (const ELFYAML::AddrsigSymbol &Sym : *Section.Symbols) {
+ uint64_t Val =
+ Sym.Name ? toSymbolIndex(*Sym.Name, Section.Name, /*IsDynamic=*/false)
+ : (uint32_t)*Sym.Index;
+ SHeader.sh_size += encodeULEB128(Val, OS);
+ }
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::NoteSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+ uint64_t Offset = OS.tell();
+
+ if (Section.Content || Section.Size) {
+ SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
+ return;
+ }
+
+ for (const ELFYAML::NoteEntry &NE : *Section.Notes) {
+ // Write name size.
+ if (NE.Name.empty())
+ support::endian::write<uint32_t>(OS, 0, ELFT::TargetEndianness);
+ else
+ support::endian::write<uint32_t>(OS, NE.Name.size() + 1,
+ ELFT::TargetEndianness);
+
+ // Write description size.
+ if (NE.Desc.binary_size() == 0)
+ support::endian::write<uint32_t>(OS, 0, ELFT::TargetEndianness);
+ else
+ support::endian::write<uint32_t>(OS, NE.Desc.binary_size(),
+ ELFT::TargetEndianness);
+
+ // Write type.
+ support::endian::write<uint32_t>(OS, NE.Type, ELFT::TargetEndianness);
+
+ // Write name, null terminator and padding.
+ if (!NE.Name.empty()) {
+ support::endian::write<uint8_t>(OS, arrayRefFromStringRef(NE.Name),
+ ELFT::TargetEndianness);
+ support::endian::write<uint8_t>(OS, 0, ELFT::TargetEndianness);
+ CBA.padToAlignment(4);
+ }
+
+ // Write description and padding.
+ if (NE.Desc.binary_size() != 0) {
+ NE.Desc.writeAsBinary(OS);
+ CBA.padToAlignment(4);
+ }
+ }
+
+ SHeader.sh_size = OS.tell() - Offset;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
+ const ELFYAML::GnuHashSection &Section,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS =
+ CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
+
+ unsigned Link = 0;
+ if (Section.Link.empty() && SN2I.lookup(".dynsym", Link))
+ SHeader.sh_link = Link;
+
+ if (Section.Content) {
+ SHeader.sh_size = writeContent(OS, Section.Content, None);
+ return;
+ }
+
+ // We write the header first, starting with the hash buckets count. Normally
+ // it is the number of entries in HashBuckets, but the "NBuckets" property can
+ // be used to override this field, which is useful for producing broken
+ // objects.
+ if (Section.Header->NBuckets)
+ support::endian::write<uint32_t>(OS, *Section.Header->NBuckets,
+ ELFT::TargetEndianness);
+ else
+ support::endian::write<uint32_t>(OS, Section.HashBuckets->size(),
+ ELFT::TargetEndianness);
+
+ // Write the index of the first symbol in the dynamic symbol table accessible
+ // via the hash table.
+ support::endian::write<uint32_t>(OS, Section.Header->SymNdx,
+ ELFT::TargetEndianness);
+
+ // Write the number of words in the Bloom filter. As above, the "MaskWords"
+ // property can be used to set this field to any value.
+ if (Section.Header->MaskWords)
+ support::endian::write<uint32_t>(OS, *Section.Header->MaskWords,
+ ELFT::TargetEndianness);
+ else
+ support::endian::write<uint32_t>(OS, Section.BloomFilter->size(),
+ ELFT::TargetEndianness);
+
+ // Write the shift constant used by the Bloom filter.
+ support::endian::write<uint32_t>(OS, Section.Header->Shift2,
+ ELFT::TargetEndianness);
+
+ // We've finished writing the header. Now write the Bloom filter.
+ for (llvm::yaml::Hex64 Val : *Section.BloomFilter)
+ support::endian::write<typename ELFT::uint>(OS, Val,
+ ELFT::TargetEndianness);
+
+ // Write an array of hash buckets.
+ for (llvm::yaml::Hex32 Val : *Section.HashBuckets)
+ support::endian::write<uint32_t>(OS, Val, ELFT::TargetEndianness);
+
+ // Write an array of hash values.
+ for (llvm::yaml::Hex32 Val : *Section.HashValues)
+ support::endian::write<uint32_t>(OS, Val, ELFT::TargetEndianness);
+
+ SHeader.sh_size = 16 /*Header size*/ +
+ Section.BloomFilter->size() * sizeof(typename ELFT::uint) +
+ Section.HashBuckets->size() * 4 +
+ Section.HashValues->size() * 4;
+}
+
+template <class ELFT>
+void ELFState<ELFT>::writeFill(ELFYAML::Fill &Fill,
+ ContiguousBlobAccumulator &CBA) {
+ raw_ostream &OS = CBA.getOSAndAlignedOffset(Fill.ShOffset, /*Align=*/1);
+
+ size_t PatternSize = Fill.Pattern ? Fill.Pattern->binary_size() : 0;
+ if (!PatternSize) {
+ OS.write_zeros(Fill.Size);
+ return;
+ }
+
+ // Fill the content with the specified pattern.
+ uint64_t Written = 0;
+ for (; Written + PatternSize <= Fill.Size; Written += PatternSize)
+ Fill.Pattern->writeAsBinary(OS);
+ Fill.Pattern->writeAsBinary(OS, Fill.Size - Written);
+}
+
+template <class ELFT> void ELFState<ELFT>::buildSectionIndex() {
+ size_t SecNdx = -1;
+ StringSet<> Seen;
+ for (size_t I = 0; I < Doc.Chunks.size(); ++I) {
+ const std::unique_ptr<ELFYAML::Chunk> &C = Doc.Chunks[I];
+ bool IsSection = isa<ELFYAML::Section>(C.get());
+ if (IsSection)
+ ++SecNdx;
+
+ if (C->Name.empty())
+ continue;
+
+ if (!Seen.insert(C->Name).second)
+ reportError("repeated section/fill name: '" + C->Name +
+ "' at YAML section/fill number " + Twine(I));
+ if (!IsSection || HasError)
+ continue;
+
+ if (!SN2I.addName(C->Name, SecNdx))
+ llvm_unreachable("buildSectionIndex() failed");
+ DotShStrtab.add(ELFYAML::dropUniqueSuffix(C->Name));
+ }
+
+ DotShStrtab.finalize();
+}
+
+template <class ELFT> void ELFState<ELFT>::buildSymbolIndexes() {
+ auto Build = [this](ArrayRef<ELFYAML::Symbol> V, NameToIdxMap &Map) {
+ for (size_t I = 0, S = V.size(); I < S; ++I) {
+ const ELFYAML::Symbol &Sym = V[I];
+ if (!Sym.Name.empty() && !Map.addName(Sym.Name, I + 1))
+ reportError("repeated symbol name: '" + Sym.Name + "'");
+ }
+ };
+
+ if (Doc.Symbols)
+ Build(*Doc.Symbols, SymN2I);
+ if (Doc.DynamicSymbols)
+ Build(*Doc.DynamicSymbols, DynSymN2I);
+}
+
+template <class ELFT> void ELFState<ELFT>::finalizeStrings() {
+ // Add the regular symbol names to .strtab section.
+ if (Doc.Symbols)
+ for (const ELFYAML::Symbol &Sym : *Doc.Symbols)
+ DotStrtab.add(ELFYAML::dropUniqueSuffix(Sym.Name));
+ DotStrtab.finalize();
+
+ // Add the dynamic symbol names to .dynstr section.
+ if (Doc.DynamicSymbols)
+ for (const ELFYAML::Symbol &Sym : *Doc.DynamicSymbols)
+ DotDynstr.add(ELFYAML::dropUniqueSuffix(Sym.Name));
+
+ // SHT_GNU_verdef and SHT_GNU_verneed sections might also
+ // add strings to .dynstr section.
+ for (const ELFYAML::Chunk *Sec : Doc.getSections()) {
+ if (auto VerNeed = dyn_cast<ELFYAML::VerneedSection>(Sec)) {
+ if (VerNeed->VerneedV) {
+ for (const ELFYAML::VerneedEntry &VE : *VerNeed->VerneedV) {
+ DotDynstr.add(VE.File);
+ for (const ELFYAML::VernauxEntry &Aux : VE.AuxV)
+ DotDynstr.add(Aux.Name);
+ }
+ }
+ } else if (auto VerDef = dyn_cast<ELFYAML::VerdefSection>(Sec)) {
+ if (VerDef->Entries)
+ for (const ELFYAML::VerdefEntry &E : *VerDef->Entries)
+ for (StringRef Name : E.VerNames)
+ DotDynstr.add(Name);
+ }
+ }
+
+ DotDynstr.finalize();
+}
+
+template <class ELFT>
+bool ELFState<ELFT>::writeELF(raw_ostream &OS, ELFYAML::Object &Doc,
+ yaml::ErrorHandler EH) {
+ ELFState<ELFT> State(Doc, EH);
+
+ // Finalize .strtab and .dynstr sections. We do that early because want to
+ // finalize the string table builders before writing the content of the
+ // sections that might want to use them.
+ State.finalizeStrings();
+
+ State.buildSectionIndex();
+ if (State.HasError)
+ return false;
+
+ State.buildSymbolIndexes();
+
+ std::vector<Elf_Phdr> PHeaders;
+ State.initProgramHeaders(PHeaders);
+
+ // XXX: This offset is tightly coupled with the order that we write
+ // things to `OS`.
+ const size_t SectionContentBeginOffset =
+ sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * Doc.ProgramHeaders.size();
+ ContiguousBlobAccumulator CBA(SectionContentBeginOffset);
+
+ std::vector<Elf_Shdr> SHeaders;
+ State.initSectionHeaders(SHeaders, CBA);
+
+ // Now we can decide segment offsets.
+ State.setProgramHeaderLayout(PHeaders, SHeaders);
+
+ if (State.HasError)
+ return false;
+
+ State.writeELFHeader(CBA, OS);
+ writeArrayData(OS, makeArrayRef(PHeaders));
+ CBA.writeBlobToStream(OS);
+ writeArrayData(OS, makeArrayRef(SHeaders));
+ return true;
+}
+
+namespace llvm {
+namespace yaml {
+
+bool yaml2elf(llvm::ELFYAML::Object &Doc, raw_ostream &Out, ErrorHandler EH) {
+ bool IsLE = Doc.Header.Data == ELFYAML::ELF_ELFDATA(ELF::ELFDATA2LSB);
+ bool Is64Bit = Doc.Header.Class == ELFYAML::ELF_ELFCLASS(ELF::ELFCLASS64);
+ if (Is64Bit) {
+ if (IsLE)
+ return ELFState<object::ELF64LE>::writeELF(Out, Doc, EH);
+ return ELFState<object::ELF64BE>::writeELF(Out, Doc, EH);
+ }
+ if (IsLE)
+ return ELFState<object::ELF32LE>::writeELF(Out, Doc, EH);
+ return ELFState<object::ELF32BE>::writeELF(Out, Doc, EH);
+}
+
+} // namespace yaml
+} // namespace llvm
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 15:40:05 +0000