Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 1661 deletions

diff --git a/gnu/llvm/tools/lld/ELF/Driver.cpp b/gnu/llvm/tools/lld/ELF/Driver.cpp
deleted file mode 100644
index 53c94ea34d8..00000000000
--- a/gnu/llvm/tools/lld/ELF/Driver.cpp
+++ /dev/null
@@ -1,1661 +0,0 @@
-//===- Driver.cpp ---------------------------------------------------------===//
-//
-//                             The LLVM Linker
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// The driver drives the entire linking process. It is responsible for
-// parsing command line options and doing whatever it is instructed to do.
-//
-// One notable thing in the LLD's driver when compared to other linkers is
-// that the LLD's driver is agnostic on the host operating system.
-// Other linkers usually have implicit default values (such as a dynamic
-// linker path or library paths) for each host OS.
-//
-// I don't think implicit default values are useful because they are
-// usually explicitly specified by the compiler driver. They can even
-// be harmful when you are doing cross-linking. Therefore, in LLD, we
-// simply trust the compiler driver to pass all required options and
-// don't try to make effort on our side.
-//
-//===----------------------------------------------------------------------===//
-
-#include "Driver.h"
-#include "Config.h"
-#include "Filesystem.h"
-#include "ICF.h"
-#include "InputFiles.h"
-#include "InputSection.h"
-#include "LinkerScript.h"
-#include "MarkLive.h"
-#include "OutputSections.h"
-#include "ScriptParser.h"
-#include "SymbolTable.h"
-#include "Symbols.h"
-#include "SyntheticSections.h"
-#include "Target.h"
-#include "Writer.h"
-#include "lld/Common/Args.h"
-#include "lld/Common/Driver.h"
-#include "lld/Common/ErrorHandler.h"
-#include "lld/Common/Memory.h"
-#include "lld/Common/Strings.h"
-#include "lld/Common/TargetOptionsCommandFlags.h"
-#include "lld/Common/Threads.h"
-#include "lld/Common/Version.h"
-#include "llvm/ADT/SetVector.h"
-#include "llvm/ADT/StringExtras.h"
-#include "llvm/ADT/StringSwitch.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Compression.h"
-#include "llvm/Support/LEB128.h"
-#include "llvm/Support/Path.h"
-#include "llvm/Support/TarWriter.h"
-#include "llvm/Support/TargetSelect.h"
-#include "llvm/Support/raw_ostream.h"
-#include <cstdlib>
-#include <utility>
-
-using namespace llvm;
-using namespace llvm::ELF;
-using namespace llvm::object;
-using namespace llvm::sys;
-using namespace llvm::support;
-
-using namespace lld;
-using namespace lld::elf;
-
-Configuration *elf::Config;
-LinkerDriver *elf::Driver;
-
-static void setConfigs(opt::InputArgList &Args);
-
-bool elf::link(ArrayRef<const char *> Args, bool CanExitEarly,
-               raw_ostream &Error) {
-  errorHandler().LogName = args::getFilenameWithoutExe(Args[0]);
-  errorHandler().ErrorLimitExceededMsg =
-      "too many errors emitted, stopping now (use "
-      "-error-limit=0 to see all errors)";
-  errorHandler().ErrorOS = &Error;
-  errorHandler().ExitEarly = CanExitEarly;
-  errorHandler().ColorDiagnostics = Error.has_colors();
-
-  InputSections.clear();
-  OutputSections.clear();
-  BinaryFiles.clear();
-  BitcodeFiles.clear();
-  ObjectFiles.clear();
-  SharedFiles.clear();
-
-  Config = make<Configuration>();
-  Driver = make<LinkerDriver>();
-  Script = make<LinkerScript>();
-  Symtab = make<SymbolTable>();
-
-  Tar = nullptr;
-  memset(&In, 0, sizeof(In));
-
-  Config->ProgName = Args[0];
-
-  Driver->main(Args);
-
-  // Exit immediately if we don't need to return to the caller.
-  // This saves time because the overhead of calling destructors
-  // for all globally-allocated objects is not negligible.
-  if (CanExitEarly)
-    exitLld(errorCount() ? 1 : 0);
-
-  freeArena();
-  return !errorCount();
-}
-
-// Parses a linker -m option.
-static std::tuple<ELFKind, uint16_t, uint8_t> parseEmulation(StringRef Emul) {
-  uint8_t OSABI = 0;
-  StringRef S = Emul;
-  if (S.endswith("_fbsd")) {
-    S = S.drop_back(5);
-    OSABI = ELFOSABI_FREEBSD;
-  }
-
-  std::pair<ELFKind, uint16_t> Ret =
-      StringSwitch<std::pair<ELFKind, uint16_t>>(S)
-          .Cases("aarch64elf", "aarch64linux", "aarch64_elf64_le_vec",
-                 {ELF64LEKind, EM_AARCH64})
-          .Cases("armelf", "armelf_linux_eabi", {ELF32LEKind, EM_ARM})
-          .Case("elf32_x86_64", {ELF32LEKind, EM_X86_64})
-          .Cases("elf32btsmip", "elf32btsmipn32", {ELF32BEKind, EM_MIPS})
-          .Cases("elf32ltsmip", "elf32ltsmipn32", {ELF32LEKind, EM_MIPS})
-          .Case("elf32lriscv", {ELF32LEKind, EM_RISCV})
-          .Cases("elf32ppc", "elf32ppclinux", {ELF32BEKind, EM_PPC})
-          .Case("elf64_sparc", {ELF64BEKind, EM_SPARCV9})
-          .Case("elf64btsmip", {ELF64BEKind, EM_MIPS})
-          .Case("elf64ltsmip", {ELF64LEKind, EM_MIPS})
-          .Case("elf64lriscv", {ELF64LEKind, EM_RISCV})
-          .Case("elf64ppc", {ELF64BEKind, EM_PPC64})
-          .Case("elf64lppc", {ELF64LEKind, EM_PPC64})
-          .Cases("elf_amd64", "elf_x86_64", {ELF64LEKind, EM_X86_64})
-          .Case("elf_i386", {ELF32LEKind, EM_386})
-          .Case("elf_iamcu", {ELF32LEKind, EM_IAMCU})
-          .Default({ELFNoneKind, EM_NONE});
-
-  if (Ret.first == ELFNoneKind)
-    error("unknown emulation: " + Emul);
-  return std::make_tuple(Ret.first, Ret.second, OSABI);
-}
-
-// Returns slices of MB by parsing MB as an archive file.
-// Each slice consists of a member file in the archive.
-std::vector<std::pair<MemoryBufferRef, uint64_t>> static getArchiveMembers(
-    MemoryBufferRef MB) {
-  std::unique_ptr<Archive> File =
-      CHECK(Archive::create(MB),
-            MB.getBufferIdentifier() + ": failed to parse archive");
-
-  std::vector<std::pair<MemoryBufferRef, uint64_t>> V;
-  Error Err = Error::success();
-  bool AddToTar = File->isThin() && Tar;
-  for (const ErrorOr<Archive::Child> &COrErr : File->children(Err)) {
-    Archive::Child C =
-        CHECK(COrErr, MB.getBufferIdentifier() +
-                          ": could not get the child of the archive");
-    MemoryBufferRef MBRef =
-        CHECK(C.getMemoryBufferRef(),
-              MB.getBufferIdentifier() +
-                  ": could not get the buffer for a child of the archive");
-    if (AddToTar)
-      Tar->append(relativeToRoot(check(C.getFullName())), MBRef.getBuffer());
-    V.push_back(std::make_pair(MBRef, C.getChildOffset()));
-  }
-  if (Err)
-    fatal(MB.getBufferIdentifier() + ": Archive::children failed: " +
-          toString(std::move(Err)));
-
-  // Take ownership of memory buffers created for members of thin archives.
-  for (std::unique_ptr<MemoryBuffer> &MB : File->takeThinBuffers())
-    make<std::unique_ptr<MemoryBuffer>>(std::move(MB));
-
-  return V;
-}
-
-// Opens a file and create a file object. Path has to be resolved already.
-void LinkerDriver::addFile(StringRef Path, bool WithLOption) {
-  using namespace sys::fs;
-
-  Optional<MemoryBufferRef> Buffer = readFile(Path);
-  if (!Buffer.hasValue())
-    return;
-  MemoryBufferRef MBRef = *Buffer;
-
-  if (Config->FormatBinary) {
-    Files.push_back(make<BinaryFile>(MBRef));
-    return;
-  }
-
-  switch (identify_magic(MBRef.getBuffer())) {
-  case file_magic::unknown:
-    readLinkerScript(MBRef);
-    return;
-  case file_magic::archive: {
-    // Handle -whole-archive.
-    if (InWholeArchive) {
-      for (const auto &P : getArchiveMembers(MBRef))
-        Files.push_back(createObjectFile(P.first, Path, P.second));
-      return;
-    }
-
-    std::unique_ptr<Archive> File =
-        CHECK(Archive::create(MBRef), Path + ": failed to parse archive");
-
-    // If an archive file has no symbol table, it is likely that a user
-    // is attempting LTO and using a default ar command that doesn't
-    // understand the LLVM bitcode file. It is a pretty common error, so
-    // we'll handle it as if it had a symbol table.
-    if (!File->isEmpty() && !File->hasSymbolTable()) {
-      for (const auto &P : getArchiveMembers(MBRef))
-        Files.push_back(make<LazyObjFile>(P.first, Path, P.second));
-      return;
-    }
-
-    // Handle the regular case.
-    Files.push_back(make<ArchiveFile>(std::move(File)));
-    return;
-  }
-  case file_magic::elf_shared_object:
-    if (Config->Static || Config->Relocatable) {
-      error("attempted static link of dynamic object " + Path);
-      return;
-    }
-
-    // DSOs usually have DT_SONAME tags in their ELF headers, and the
-    // sonames are used to identify DSOs. But if they are missing,
-    // they are identified by filenames. We don't know whether the new
-    // file has a DT_SONAME or not because we haven't parsed it yet.
-    // Here, we set the default soname for the file because we might
-    // need it later.
-    //
-    // If a file was specified by -lfoo, the directory part is not
-    // significant, as a user did not specify it. This behavior is
-    // compatible with GNU.
-    Files.push_back(
-        createSharedFile(MBRef, WithLOption ? path::filename(Path) : Path));
-    return;
-  case file_magic::bitcode:
-  case file_magic::elf_relocatable:
-    if (InLib)
-      Files.push_back(make<LazyObjFile>(MBRef, "", 0));
-    else
-      Files.push_back(createObjectFile(MBRef));
-    break;
-  default:
-    error(Path + ": unknown file type");
-  }
-}
-
-// Add a given library by searching it from input search paths.
-void LinkerDriver::addLibrary(StringRef Name) {
-  if (Optional<std::string> Path = searchLibrary(Name))
-    addFile(*Path, /*WithLOption=*/true);
-  else
-    error("unable to find library -l" + Name);
-}
-
-// This function is called on startup. We need this for LTO since
-// LTO calls LLVM functions to compile bitcode files to native code.
-// Technically this can be delayed until we read bitcode files, but
-// we don't bother to do lazily because the initialization is fast.
-static void initLLVM() {
-  InitializeAllTargets();
-  InitializeAllTargetMCs();
-  InitializeAllAsmPrinters();
-  InitializeAllAsmParsers();
-}
-
-// Some command line options or some combinations of them are not allowed.
-// This function checks for such errors.
-static void checkOptions() {
-  // The MIPS ABI as of 2016 does not support the GNU-style symbol lookup
-  // table which is a relatively new feature.
-  if (Config->EMachine == EM_MIPS && Config->GnuHash)
-    error("the .gnu.hash section is not compatible with the MIPS target");
-
-  if (Config->FixCortexA53Errata843419 && Config->EMachine != EM_AARCH64)
-    error("--fix-cortex-a53-843419 is only supported on AArch64 targets");
-
-  if (Config->TocOptimize && Config->EMachine != EM_PPC64)
-    error("--toc-optimize is only supported on the PowerPC64 target");
-
-  if (Config->Pie && Config->Shared)
-    error("-shared and -pie may not be used together");
-
-  if (!Config->Shared && !Config->FilterList.empty())
-    error("-F may not be used without -shared");
-
-  if (!Config->Shared && !Config->AuxiliaryList.empty())
-    error("-f may not be used without -shared");
-
-  if (!Config->Relocatable && !Config->DefineCommon)
-    error("-no-define-common not supported in non relocatable output");
-
-  if (Config->Relocatable) {
-    if (Config->Shared)
-      error("-r and -shared may not be used together");
-    if (Config->GcSections)
-      error("-r and --gc-sections may not be used together");
-    if (Config->GdbIndex)
-      error("-r and --gdb-index may not be used together");
-    if (Config->ICF != ICFLevel::None)
-      error("-r and --icf may not be used together");
-    if (Config->Pie)
-      error("-r and -pie may not be used together");
-  }
-
-  if (Config->ExecuteOnly) {
-    if (Config->EMachine != EM_AARCH64)
-      error("-execute-only is only supported on AArch64 targets");
-
-    if (Config->SingleRoRx && !Script->HasSectionsCommand)
-      error("-execute-only and -no-rosegment cannot be used together");
-  }
-}
-
-static const char *getReproduceOption(opt::InputArgList &Args) {
-  if (auto *Arg = Args.getLastArg(OPT_reproduce))
-    return Arg->getValue();
-  return getenv("LLD_REPRODUCE");
-}
-
-static bool hasZOption(opt::InputArgList &Args, StringRef Key) {
-  for (auto *Arg : Args.filtered(OPT_z))
-    if (Key == Arg->getValue())
-      return true;
-  return false;
-}
-
-static bool getZFlag(opt::InputArgList &Args, StringRef K1, StringRef K2,
-                     bool Default) {
-  for (auto *Arg : Args.filtered_reverse(OPT_z)) {
-    if (K1 == Arg->getValue())
-      return true;
-    if (K2 == Arg->getValue())
-      return false;
-  }
-  return Default;
-}
-
-static bool isKnownZFlag(StringRef S) {
-  return S == "combreloc" || S == "copyreloc" || S == "defs" ||
-         S == "execstack" || S == "global" || S == "hazardplt" ||
-         S == "initfirst" || S == "interpose" ||
-         S == "keep-text-section-prefix" || S == "lazy" || S == "muldefs" ||
-         S == "nocombreloc" || S == "nocopyreloc" || S == "nodefaultlib" ||
-         S == "nodelete" || S == "nodlopen" || S == "noexecstack" ||
-         S == "nokeep-text-section-prefix" || S == "norelro" ||
-         S == "noretpolineplt" || S == "notext" ||
-         S == "now" || S == "origin" || S == "relro" || S == "retpolineplt" ||
-         S == "rodynamic" || S == "text" || S == "wxneeded" ||
-         S.startswith("max-page-size=") || S.startswith("stack-size=");
-}
-
-// Report an error for an unknown -z option.
-static void checkZOptions(opt::InputArgList &Args) {
-  for (auto *Arg : Args.filtered(OPT_z))
-    if (!isKnownZFlag(Arg->getValue()))
-      error("unknown -z value: " + StringRef(Arg->getValue()));
-}
-
-void LinkerDriver::main(ArrayRef<const char *> ArgsArr) {
-  ELFOptTable Parser;
-  opt::InputArgList Args = Parser.parse(ArgsArr.slice(1));
-
-  // Interpret this flag early because error() depends on them.
-  errorHandler().ErrorLimit = args::getInteger(Args, OPT_error_limit, 20);
-
-  // Handle -help
-  if (Args.hasArg(OPT_help)) {
-    printHelp();
-    return;
-  }
-
-  // Handle -v or -version.
-  //
-  // A note about "compatible with GNU linkers" message: this is a hack for
-  // scripts generated by GNU Libtool 2.4.6 (released in February 2014 and
-  // still the newest version in March 2017) or earlier to recognize LLD as
-  // a GNU compatible linker. As long as an output for the -v option
-  // contains "GNU" or "with BFD", they recognize us as GNU-compatible.
-  //
-  // This is somewhat ugly hack, but in reality, we had no choice other
-  // than doing this. Considering the very long release cycle of Libtool,
-  // it is not easy to improve it to recognize LLD as a GNU compatible
-  // linker in a timely manner. Even if we can make it, there are still a
-  // lot of "configure" scripts out there that are generated by old version
-  // of Libtool. We cannot convince every software developer to migrate to
-  // the latest version and re-generate scripts. So we have this hack.
-  if (Args.hasArg(OPT_v) || Args.hasArg(OPT_version))
-    message(getLLDVersion() + " (compatible with GNU linkers)");
-
-  if (const char *Path = getReproduceOption(Args)) {
-    // Note that --reproduce is a debug option so you can ignore it
-    // if you are trying to understand the whole picture of the code.
-    Expected<std::unique_ptr<TarWriter>> ErrOrWriter =
-        TarWriter::create(Path, path::stem(Path));
-    if (ErrOrWriter) {
-      Tar = std::move(*ErrOrWriter);
-      Tar->append("response.txt", createResponseFile(Args));
-      Tar->append("version.txt", getLLDVersion() + "\n");
-    } else {
-      error("--reproduce: " + toString(ErrOrWriter.takeError()));
-    }
-  }
-
-  readConfigs(Args);
-  checkZOptions(Args);
-
-  // The behavior of -v or --version is a bit strange, but this is
-  // needed for compatibility with GNU linkers.
-  if (Args.hasArg(OPT_v) && !Args.hasArg(OPT_INPUT))
-    return;
-  if (Args.hasArg(OPT_version))
-    return;
-
-  initLLVM();
-  createFiles(Args);
-  if (errorCount())
-    return;
-
-  inferMachineType();
-  setConfigs(Args);
-  checkOptions();
-  if (errorCount())
-    return;
-
-  switch (Config->EKind) {
-  case ELF32LEKind:
-    link<ELF32LE>(Args);
-    return;
-  case ELF32BEKind:
-    link<ELF32BE>(Args);
-    return;
-  case ELF64LEKind:
-    link<ELF64LE>(Args);
-    return;
-  case ELF64BEKind:
-    link<ELF64BE>(Args);
-    return;
-  default:
-    llvm_unreachable("unknown Config->EKind");
-  }
-}
-
-static std::string getRpath(opt::InputArgList &Args) {
-  std::vector<StringRef> V = args::getStrings(Args, OPT_rpath);
-  return llvm::join(V.begin(), V.end(), ":");
-}
-
-// Determines what we should do if there are remaining unresolved
-// symbols after the name resolution.
-static UnresolvedPolicy getUnresolvedSymbolPolicy(opt::InputArgList &Args) {
-  UnresolvedPolicy ErrorOrWarn = Args.hasFlag(OPT_error_unresolved_symbols,
-                                              OPT_warn_unresolved_symbols, true)
-                                     ? UnresolvedPolicy::ReportError
-                                     : UnresolvedPolicy::Warn;
-
-  // Process the last of -unresolved-symbols, -no-undefined or -z defs.
-  for (auto *Arg : llvm::reverse(Args)) {
-    switch (Arg->getOption().getID()) {
-    case OPT_unresolved_symbols: {
-      StringRef S = Arg->getValue();
-      if (S == "ignore-all" || S == "ignore-in-object-files")
-        return UnresolvedPolicy::Ignore;
-      if (S == "ignore-in-shared-libs" || S == "report-all")
-        return ErrorOrWarn;
-      error("unknown --unresolved-symbols value: " + S);
-      continue;
-    }
-    case OPT_no_undefined:
-      return ErrorOrWarn;
-    case OPT_z:
-      if (StringRef(Arg->getValue()) == "defs")
-        return ErrorOrWarn;
-      continue;
-    }
-  }
-
-  // -shared implies -unresolved-symbols=ignore-all because missing
-  // symbols are likely to be resolved at runtime using other DSOs.
-  if (Config->Shared)
-    return UnresolvedPolicy::Ignore;
-  return ErrorOrWarn;
-}
-
-static Target2Policy getTarget2(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_target2, "got-rel");
-  if (S == "rel")
-    return Target2Policy::Rel;
-  if (S == "abs")
-    return Target2Policy::Abs;
-  if (S == "got-rel")
-    return Target2Policy::GotRel;
-  error("unknown --target2 option: " + S);
-  return Target2Policy::GotRel;
-}
-
-static bool isOutputFormatBinary(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_oformat, "elf");
-  if (S == "binary")
-    return true;
-  if (!S.startswith("elf"))
-    error("unknown --oformat value: " + S);
-  return false;
-}
-
-static DiscardPolicy getDiscard(opt::InputArgList &Args) {
-  if (Args.hasArg(OPT_relocatable))
-    return DiscardPolicy::None;
-
-  auto *Arg =
-      Args.getLastArg(OPT_discard_all, OPT_discard_locals, OPT_discard_none);
-  if (!Arg)
-    return DiscardPolicy::Default;
-  if (Arg->getOption().getID() == OPT_discard_all)
-    return DiscardPolicy::All;
-  if (Arg->getOption().getID() == OPT_discard_locals)
-    return DiscardPolicy::Locals;
-  return DiscardPolicy::None;
-}
-
-static StringRef getDynamicLinker(opt::InputArgList &Args) {
-  auto *Arg = Args.getLastArg(OPT_dynamic_linker, OPT_no_dynamic_linker);
-  if (!Arg || Arg->getOption().getID() == OPT_no_dynamic_linker)
-    return "";
-  return Arg->getValue();
-}
-
-static ICFLevel getICF(opt::InputArgList &Args) {
-  auto *Arg = Args.getLastArg(OPT_icf_none, OPT_icf_safe, OPT_icf_all);
-  if (!Arg || Arg->getOption().getID() == OPT_icf_none)
-    return ICFLevel::None;
-  if (Arg->getOption().getID() == OPT_icf_safe)
-    return ICFLevel::Safe;
-  return ICFLevel::All;
-}
-
-static StripPolicy getStrip(opt::InputArgList &Args) {
-  if (Args.hasArg(OPT_relocatable))
-    return StripPolicy::None;
-
-  auto *Arg = Args.getLastArg(OPT_strip_all, OPT_strip_debug);
-  if (!Arg)
-    return StripPolicy::None;
-  if (Arg->getOption().getID() == OPT_strip_all)
-    return StripPolicy::All;
-  return StripPolicy::Debug;
-}
-
-static uint64_t parseSectionAddress(StringRef S, const opt::Arg &Arg) {
-  uint64_t VA = 0;
-  if (S.startswith("0x"))
-    S = S.drop_front(2);
-  if (!to_integer(S, VA, 16))
-    error("invalid argument: " + toString(Arg));
-  return VA;
-}
-
-static StringMap<uint64_t> getSectionStartMap(opt::InputArgList &Args) {
-  StringMap<uint64_t> Ret;
-  for (auto *Arg : Args.filtered(OPT_section_start)) {
-    StringRef Name;
-    StringRef Addr;
-    std::tie(Name, Addr) = StringRef(Arg->getValue()).split('=');
-    Ret[Name] = parseSectionAddress(Addr, *Arg);
-  }
-
-  if (auto *Arg = Args.getLastArg(OPT_Ttext))
-    Ret[".text"] = parseSectionAddress(Arg->getValue(), *Arg);
-  if (auto *Arg = Args.getLastArg(OPT_Tdata))
-    Ret[".data"] = parseSectionAddress(Arg->getValue(), *Arg);
-  if (auto *Arg = Args.getLastArg(OPT_Tbss))
-    Ret[".bss"] = parseSectionAddress(Arg->getValue(), *Arg);
-  return Ret;
-}
-
-static SortSectionPolicy getSortSection(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_sort_section);
-  if (S == "alignment")
-    return SortSectionPolicy::Alignment;
-  if (S == "name")
-    return SortSectionPolicy::Name;
-  if (!S.empty())
-    error("unknown --sort-section rule: " + S);
-  return SortSectionPolicy::Default;
-}
-
-static OrphanHandlingPolicy getOrphanHandling(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_orphan_handling, "place");
-  if (S == "warn")
-    return OrphanHandlingPolicy::Warn;
-  if (S == "error")
-    return OrphanHandlingPolicy::Error;
-  if (S != "place")
-    error("unknown --orphan-handling mode: " + S);
-  return OrphanHandlingPolicy::Place;
-}
-
-// Parse --build-id or --build-id=<style>. We handle "tree" as a
-// synonym for "sha1" because all our hash functions including
-// -build-id=sha1 are actually tree hashes for performance reasons.
-static std::pair<BuildIdKind, std::vector<uint8_t>>
-getBuildId(opt::InputArgList &Args) {
-  auto *Arg = Args.getLastArg(OPT_build_id, OPT_build_id_eq);
-  if (!Arg)
-    return {BuildIdKind::None, {}};
-
-  if (Arg->getOption().getID() == OPT_build_id)
-    return {BuildIdKind::Fast, {}};
-
-  StringRef S = Arg->getValue();
-  if (S == "fast")
-    return {BuildIdKind::Fast, {}};
-  if (S == "md5")
-    return {BuildIdKind::Md5, {}};
-  if (S == "sha1" || S == "tree")
-    return {BuildIdKind::Sha1, {}};
-  if (S == "uuid")
-    return {BuildIdKind::Uuid, {}};
-  if (S.startswith("0x"))
-    return {BuildIdKind::Hexstring, parseHex(S.substr(2))};
-
-  if (S != "none")
-    error("unknown --build-id style: " + S);
-  return {BuildIdKind::None, {}};
-}
-
-static std::pair<bool, bool> getPackDynRelocs(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_pack_dyn_relocs, "none");
-  if (S == "android")
-    return {true, false};
-  if (S == "relr")
-    return {false, true};
-  if (S == "android+relr")
-    return {true, true};
-
-  if (S != "none")
-    error("unknown -pack-dyn-relocs format: " + S);
-  return {false, false};
-}
-
-static void readCallGraph(MemoryBufferRef MB) {
-  // Build a map from symbol name to section
-  DenseMap<StringRef, Symbol *> Map;
-  for (InputFile *File : ObjectFiles)
-    for (Symbol *Sym : File->getSymbols())
-      Map[Sym->getName()] = Sym;
-
-  auto FindSection = [&](StringRef Name) -> InputSectionBase * {
-    Symbol *Sym = Map.lookup(Name);
-    if (!Sym) {
-      if (Config->WarnSymbolOrdering)
-        warn(MB.getBufferIdentifier() + ": no such symbol: " + Name);
-      return nullptr;
-    }
-    maybeWarnUnorderableSymbol(Sym);
-
-    if (Defined *DR = dyn_cast_or_null<Defined>(Sym))
-      return dyn_cast_or_null<InputSectionBase>(DR->Section);
-    return nullptr;
-  };
-
-  for (StringRef Line : args::getLines(MB)) {
-    SmallVector<StringRef, 3> Fields;
-    Line.split(Fields, ' ');
-    uint64_t Count;
-
-    if (Fields.size() != 3 || !to_integer(Fields[2], Count)) {
-      error(MB.getBufferIdentifier() + ": parse error");
-      return;
-    }
-
-    if (InputSectionBase *From = FindSection(Fields[0]))
-      if (InputSectionBase *To = FindSection(Fields[1]))
-        Config->CallGraphProfile[std::make_pair(From, To)] += Count;
-  }
-}
-
-template <class ELFT> static void readCallGraphsFromObjectFiles() {
-  for (auto File : ObjectFiles) {
-    auto *Obj = cast<ObjFile<ELFT>>(File);
-
-    for (const Elf_CGProfile_Impl<ELFT> &CGPE : Obj->CGProfile) {
-      auto *FromSym = dyn_cast<Defined>(&Obj->getSymbol(CGPE.cgp_from));
-      auto *ToSym = dyn_cast<Defined>(&Obj->getSymbol(CGPE.cgp_to));
-      if (!FromSym || !ToSym)
-        continue;
-
-      auto *From = dyn_cast_or_null<InputSectionBase>(FromSym->Section);
-      auto *To = dyn_cast_or_null<InputSectionBase>(ToSym->Section);
-      if (From && To)
-        Config->CallGraphProfile[{From, To}] += CGPE.cgp_weight;
-    }
-  }
-}
-
-static bool getCompressDebugSections(opt::InputArgList &Args) {
-  StringRef S = Args.getLastArgValue(OPT_compress_debug_sections, "none");
-  if (S == "none")
-    return false;
-  if (S != "zlib")
-    error("unknown --compress-debug-sections value: " + S);
-  if (!zlib::isAvailable())
-    error("--compress-debug-sections: zlib is not available");
-  return true;
-}
-
-static std::pair<StringRef, StringRef> getOldNewOptions(opt::InputArgList &Args,
-                                                        unsigned Id) {
-  auto *Arg = Args.getLastArg(Id);
-  if (!Arg)
-    return {"", ""};
-
-  StringRef S = Arg->getValue();
-  std::pair<StringRef, StringRef> Ret = S.split(';');
-  if (Ret.second.empty())
-    error(Arg->getSpelling() + " expects 'old;new' format, but got " + S);
-  return Ret;
-}
-
-// Parse the symbol ordering file and warn for any duplicate entries.
-static std::vector<StringRef> getSymbolOrderingFile(MemoryBufferRef MB) {
-  SetVector<StringRef> Names;
-  for (StringRef S : args::getLines(MB))
-    if (!Names.insert(S) && Config->WarnSymbolOrdering)
-      warn(MB.getBufferIdentifier() + ": duplicate ordered symbol: " + S);
-
-  return Names.takeVector();
-}
-
-static void parseClangOption(StringRef Opt, const Twine &Msg) {
-  std::string Err;
-  raw_string_ostream OS(Err);
-
-  const char *Argv[] = {Config->ProgName.data(), Opt.data()};
-  if (cl::ParseCommandLineOptions(2, Argv, "", &OS))
-    return;
-  OS.flush();
-  error(Msg + ": " + StringRef(Err).trim());
-}
-
-// Initializes Config members by the command line options.
-void LinkerDriver::readConfigs(opt::InputArgList &Args) {
-  errorHandler().Verbose = Args.hasArg(OPT_verbose);
-  errorHandler().FatalWarnings =
-      Args.hasFlag(OPT_fatal_warnings, OPT_no_fatal_warnings, false);
-  ThreadsEnabled = Args.hasFlag(OPT_threads, OPT_no_threads, true);
-
-  Config->AllowMultipleDefinition =
-      Args.hasFlag(OPT_allow_multiple_definition,
-                   OPT_no_allow_multiple_definition, false) ||
-      hasZOption(Args, "muldefs");
-  Config->AuxiliaryList = args::getStrings(Args, OPT_auxiliary);
-  Config->Bsymbolic = Args.hasArg(OPT_Bsymbolic);
-  Config->BsymbolicFunctions = Args.hasArg(OPT_Bsymbolic_functions);
-  Config->CheckSections =
-      Args.hasFlag(OPT_check_sections, OPT_no_check_sections, true);
-  Config->Chroot = Args.getLastArgValue(OPT_chroot);
-  Config->CompressDebugSections = getCompressDebugSections(Args);
-  Config->Cref = Args.hasFlag(OPT_cref, OPT_no_cref, false);
-  Config->DefineCommon = Args.hasFlag(OPT_define_common, OPT_no_define_common,
-                                      !Args.hasArg(OPT_relocatable));
-  Config->Demangle = Args.hasFlag(OPT_demangle, OPT_no_demangle, true);
-  Config->DisableVerify = Args.hasArg(OPT_disable_verify);
-  Config->Discard = getDiscard(Args);
-  Config->DwoDir = Args.getLastArgValue(OPT_plugin_opt_dwo_dir_eq);
-  Config->DynamicLinker = getDynamicLinker(Args);
-  Config->EhFrameHdr =
-      Args.hasFlag(OPT_eh_frame_hdr, OPT_no_eh_frame_hdr, false);
-  Config->EmitLLVM = Args.hasArg(OPT_plugin_opt_emit_llvm, false);
-  Config->EmitRelocs = Args.hasArg(OPT_emit_relocs);
-  Config->CallGraphProfileSort = Args.hasFlag(
-      OPT_call_graph_profile_sort, OPT_no_call_graph_profile_sort, true);
-  Config->EnableNewDtags =
-      Args.hasFlag(OPT_enable_new_dtags, OPT_disable_new_dtags, true);
-  Config->Entry = Args.getLastArgValue(OPT_entry);
-  Config->ExecuteOnly =
-      Args.hasFlag(OPT_execute_only, OPT_no_execute_only, false);
-  Config->ExportDynamic =
-      Args.hasFlag(OPT_export_dynamic, OPT_no_export_dynamic, false);
-  Config->FilterList = args::getStrings(Args, OPT_filter);
-  Config->Fini = Args.getLastArgValue(OPT_fini, "_fini");
-  Config->FixCortexA53Errata843419 = Args.hasArg(OPT_fix_cortex_a53_843419);
-  Config->GcSections = Args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false);
-  Config->GnuUnique = Args.hasFlag(OPT_gnu_unique, OPT_no_gnu_unique, true);
-  Config->GdbIndex = Args.hasFlag(OPT_gdb_index, OPT_no_gdb_index, false);
-  Config->ICF = getICF(Args);
-  Config->IgnoreDataAddressEquality =
-      Args.hasArg(OPT_ignore_data_address_equality);
-  Config->IgnoreFunctionAddressEquality =
-      Args.hasFlag(OPT_ignore_function_address_equality,
-      OPT_no_ignore_function_address_equality, true);
-  Config->Init = Args.getLastArgValue(OPT_init, "_init");
-  Config->LTOAAPipeline = Args.getLastArgValue(OPT_lto_aa_pipeline);
-  Config->LTODebugPassManager = Args.hasArg(OPT_lto_debug_pass_manager);
-  Config->LTONewPassManager = Args.hasArg(OPT_lto_new_pass_manager);
-  Config->LTONewPmPasses = Args.getLastArgValue(OPT_lto_newpm_passes);
-  Config->LTOO = args::getInteger(Args, OPT_lto_O, 2);
-  Config->LTOObjPath = Args.getLastArgValue(OPT_plugin_opt_obj_path_eq);
-  Config->LTOPartitions = args::getInteger(Args, OPT_lto_partitions, 1);
-  Config->LTOSampleProfile = Args.getLastArgValue(OPT_lto_sample_profile);
-  Config->MapFile = Args.getLastArgValue(OPT_Map);
-  Config->MipsGotSize = args::getInteger(Args, OPT_mips_got_size, 0xfff0);
-  Config->MergeArmExidx =
-      Args.hasFlag(OPT_merge_exidx_entries, OPT_no_merge_exidx_entries, true);
-  Config->NoinhibitExec = Args.hasArg(OPT_noinhibit_exec);
-  Config->Nostdlib = Args.hasArg(OPT_nostdlib);
-  Config->OFormatBinary = isOutputFormatBinary(Args);
-  Config->Omagic = Args.hasFlag(OPT_omagic, OPT_no_omagic, false);
-  Config->OptRemarksFilename = Args.getLastArgValue(OPT_opt_remarks_filename);
-  Config->OptRemarksWithHotness = Args.hasArg(OPT_opt_remarks_with_hotness);
-  Config->Optimize = args::getInteger(Args, OPT_O, 1);
-  Config->OrphanHandling = getOrphanHandling(Args);
-  Config->OutputFile = Args.getLastArgValue(OPT_o);
-#ifdef __OpenBSD__
-  Config->Pie = Args.hasFlag(OPT_pie, OPT_no_pie,
-      !Args.hasArg(OPT_shared) && !Args.hasArg(OPT_relocatable));
-#else
-  Config->Pie = Args.hasFlag(OPT_pie, OPT_no_pie, false);
-#endif
-  Config->PrintIcfSections =
-      Args.hasFlag(OPT_print_icf_sections, OPT_no_print_icf_sections, false);
-  Config->PrintGcSections =
-      Args.hasFlag(OPT_print_gc_sections, OPT_no_print_gc_sections, false);
-  Config->Rpath = getRpath(Args);
-  Config->Relocatable = Args.hasArg(OPT_relocatable);
-  Config->SaveTemps = Args.hasArg(OPT_save_temps);
-  Config->SearchPaths = args::getStrings(Args, OPT_library_path);
-  Config->SectionStartMap = getSectionStartMap(Args);
-  Config->Shared = Args.hasArg(OPT_shared);
-  Config->SingleRoRx = Args.hasArg(OPT_no_rosegment);
-  Config->SoName = Args.getLastArgValue(OPT_soname);
-  Config->SortSection = getSortSection(Args);
-  Config->SplitStackAdjustSize = args::getInteger(Args, OPT_split_stack_adjust_size, 16384);
-  Config->Strip = getStrip(Args);
-  Config->Sysroot = Args.getLastArgValue(OPT_sysroot);
-  Config->Target1Rel = Args.hasFlag(OPT_target1_rel, OPT_target1_abs, false);
-  Config->Target2 = getTarget2(Args);
-  Config->ThinLTOCacheDir = Args.getLastArgValue(OPT_thinlto_cache_dir);
-  Config->ThinLTOCachePolicy = CHECK(
-      parseCachePruningPolicy(Args.getLastArgValue(OPT_thinlto_cache_policy)),
-      "--thinlto-cache-policy: invalid cache policy");
-  Config->ThinLTOEmitImportsFiles =
-      Args.hasArg(OPT_plugin_opt_thinlto_emit_imports_files);
-  Config->ThinLTOIndexOnly = Args.hasArg(OPT_plugin_opt_thinlto_index_only) ||
-                             Args.hasArg(OPT_plugin_opt_thinlto_index_only_eq);
-  Config->ThinLTOIndexOnlyArg =
-      Args.getLastArgValue(OPT_plugin_opt_thinlto_index_only_eq);
-  Config->ThinLTOJobs = args::getInteger(Args, OPT_thinlto_jobs, -1u);
-  Config->ThinLTOObjectSuffixReplace =
-      getOldNewOptions(Args, OPT_plugin_opt_thinlto_object_suffix_replace_eq);
-  Config->ThinLTOPrefixReplace =
-      getOldNewOptions(Args, OPT_plugin_opt_thinlto_prefix_replace_eq);
-  Config->Trace = Args.hasArg(OPT_trace);
-  Config->Undefined = args::getStrings(Args, OPT_undefined);
-  Config->UndefinedVersion =
-      Args.hasFlag(OPT_undefined_version, OPT_no_undefined_version, true);
-  Config->UseAndroidRelrTags = Args.hasFlag(
-      OPT_use_android_relr_tags, OPT_no_use_android_relr_tags, false);
-  Config->UnresolvedSymbols = getUnresolvedSymbolPolicy(Args);
-  Config->WarnBackrefs =
-      Args.hasFlag(OPT_warn_backrefs, OPT_no_warn_backrefs, false);
-  Config->WarnCommon = Args.hasFlag(OPT_warn_common, OPT_no_warn_common, false);
-  Config->WarnIfuncTextrel =
-      Args.hasFlag(OPT_warn_ifunc_textrel, OPT_no_warn_ifunc_textrel, false);
-  Config->WarnSymbolOrdering =
-      Args.hasFlag(OPT_warn_symbol_ordering, OPT_no_warn_symbol_ordering, true);
-  Config->ZCombreloc = getZFlag(Args, "combreloc", "nocombreloc", true);
-  Config->ZCopyreloc = getZFlag(Args, "copyreloc", "nocopyreloc", true);
-  Config->ZExecstack = getZFlag(Args, "execstack", "noexecstack", false);
-  Config->ZGlobal = hasZOption(Args, "global");
-  Config->ZHazardplt = hasZOption(Args, "hazardplt");
-  Config->ZInitfirst = hasZOption(Args, "initfirst");
-  Config->ZInterpose = hasZOption(Args, "interpose");
-  Config->ZKeepTextSectionPrefix = getZFlag(
-      Args, "keep-text-section-prefix", "nokeep-text-section-prefix", false);
-  Config->ZNodefaultlib = hasZOption(Args, "nodefaultlib");
-  Config->ZNodelete = hasZOption(Args, "nodelete");
-  Config->ZNodlopen = hasZOption(Args, "nodlopen");
-  Config->ZNow = getZFlag(Args, "now", "lazy", false);
-  Config->ZOrigin = hasZOption(Args, "origin");
-  Config->ZRelro = getZFlag(Args, "relro", "norelro", true);
-#ifndef __OpenBSD__
-  Config->ZRetpolineplt = getZFlag(Args, "retpolineplt", "noretpolineplt", false);
-#else
-  Config->ZRetpolineplt = getZFlag(Args, "retpolineplt", "noretpolineplt", true);
-#endif
-  Config->ZRodynamic = hasZOption(Args, "rodynamic");
-  Config->ZStackSize = args::getZOptionValue(Args, OPT_z, "stack-size", 0);
-  Config->ZText = getZFlag(Args, "text", "notext", true);
-  Config->ZWxneeded = hasZOption(Args, "wxneeded");
-
-  // Parse LTO options.
-  if (auto *Arg = Args.getLastArg(OPT_plugin_opt_mcpu_eq))
-    parseClangOption(Saver.save("-mcpu=" + StringRef(Arg->getValue())),
-                     Arg->getSpelling());
-
-  for (auto *Arg : Args.filtered(OPT_plugin_opt))
-    parseClangOption(Arg->getValue(), Arg->getSpelling());
-
-  // Parse -mllvm options.
-  for (auto *Arg : Args.filtered(OPT_mllvm))
-    parseClangOption(Arg->getValue(), Arg->getSpelling());
-
-  if (Config->LTOO > 3)
-    error("invalid optimization level for LTO: " + Twine(Config->LTOO));
-  if (Config->LTOPartitions == 0)
-    error("--lto-partitions: number of threads must be > 0");
-  if (Config->ThinLTOJobs == 0)
-    error("--thinlto-jobs: number of threads must be > 0");
-
-  if (Config->SplitStackAdjustSize < 0)
-    error("--split-stack-adjust-size: size must be >= 0");
-
-  // Parse ELF{32,64}{LE,BE} and CPU type.
-  if (auto *Arg = Args.getLastArg(OPT_m)) {
-    StringRef S = Arg->getValue();
-    std::tie(Config->EKind, Config->EMachine, Config->OSABI) =
-        parseEmulation(S);
-    Config->MipsN32Abi = (S == "elf32btsmipn32" || S == "elf32ltsmipn32");
-    Config->Emulation = S;
-  }
-
-  // Parse -hash-style={sysv,gnu,both}.
-  if (auto *Arg = Args.getLastArg(OPT_hash_style)) {
-    StringRef S = Arg->getValue();
-    if (S == "sysv")
-      Config->SysvHash = true;
-    else if (S == "gnu")
-      Config->GnuHash = true;
-    else if (S == "both")
-      Config->SysvHash = Config->GnuHash = true;
-    else
-      error("unknown -hash-style: " + S);
-  }
-
-  if (Args.hasArg(OPT_print_map))
-    Config->MapFile = "-";
-
-  // --omagic is an option to create old-fashioned executables in which
-  // .text segments are writable. Today, the option is still in use to
-  // create special-purpose programs such as boot loaders. It doesn't
-  // make sense to create PT_GNU_RELRO for such executables.
-  if (Config->Omagic)
-    Config->ZRelro = false;
-
-  std::tie(Config->BuildId, Config->BuildIdVector) = getBuildId(Args);
-
-  std::tie(Config->AndroidPackDynRelocs, Config->RelrPackDynRelocs) =
-      getPackDynRelocs(Args);
-
-  if (auto *Arg = Args.getLastArg(OPT_symbol_ordering_file))
-    if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
-      Config->SymbolOrderingFile = getSymbolOrderingFile(*Buffer);
-
-  // If --retain-symbol-file is used, we'll keep only the symbols listed in
-  // the file and discard all others.
-  if (auto *Arg = Args.getLastArg(OPT_retain_symbols_file)) {
-    Config->DefaultSymbolVersion = VER_NDX_LOCAL;
-    if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
-      for (StringRef S : args::getLines(*Buffer))
-        Config->VersionScriptGlobals.push_back(
-            {S, /*IsExternCpp*/ false, /*HasWildcard*/ false});
-  }
-
-  bool HasExportDynamic =
-      Args.hasFlag(OPT_export_dynamic, OPT_no_export_dynamic, false);
-
-  // Parses -dynamic-list and -export-dynamic-symbol. They make some
-  // symbols private. Note that -export-dynamic takes precedence over them
-  // as it says all symbols should be exported.
-  if (!HasExportDynamic) {
-    for (auto *Arg : Args.filtered(OPT_dynamic_list))
-      if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
-        readDynamicList(*Buffer);
-
-    for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol))
-      Config->DynamicList.push_back(
-          {Arg->getValue(), /*IsExternCpp*/ false, /*HasWildcard*/ false});
-  }
-
-  // If --export-dynamic-symbol=foo is given and symbol foo is defined in
-  // an object file in an archive file, that object file should be pulled
-  // out and linked. (It doesn't have to behave like that from technical
-  // point of view, but this is needed for compatibility with GNU.)
-  for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol))
-    Config->Undefined.push_back(Arg->getValue());
-
-  for (auto *Arg : Args.filtered(OPT_version_script))
-    if (Optional<std::string> Path = searchScript(Arg->getValue())) {
-      if (Optional<MemoryBufferRef> Buffer = readFile(*Path))
-        readVersionScript(*Buffer);
-    } else {
-      error(Twine("cannot find version script ") + Arg->getValue());
-    }
-}
-
-// Some Config members do not directly correspond to any particular
-// command line options, but computed based on other Config values.
-// This function initialize such members. See Config.h for the details
-// of these values.
-static void setConfigs(opt::InputArgList &Args) {
-  ELFKind K = Config->EKind;
-  uint16_t M = Config->EMachine;
-
-  Config->CopyRelocs = (Config->Relocatable || Config->EmitRelocs);
-  Config->Is64 = (K == ELF64LEKind || K == ELF64BEKind);
-  Config->IsLE = (K == ELF32LEKind || K == ELF64LEKind);
-  Config->Endianness = Config->IsLE ? endianness::little : endianness::big;
-  Config->IsMips64EL = (K == ELF64LEKind && M == EM_MIPS);
-  Config->Pic = Config->Pie || Config->Shared;
-  Config->PicThunk = Args.hasArg(OPT_pic_veneer, Config->Pic);
-  Config->Wordsize = Config->Is64 ? 8 : 4;
-
-  // ELF defines two different ways to store relocation addends as shown below:
-  //
-  //  Rel:  Addends are stored to the location where relocations are applied.
-  //  Rela: Addends are stored as part of relocation entry.
-  //
-  // In other words, Rela makes it easy to read addends at the price of extra
-  // 4 or 8 byte for each relocation entry. We don't know why ELF defined two
-  // different mechanisms in the first place, but this is how the spec is
-  // defined.
-  //
-  // You cannot choose which one, Rel or Rela, you want to use. Instead each
-  // ABI defines which one you need to use. The following expression expresses
-  // that.
-  Config->IsRela = M == EM_AARCH64 || M == EM_AMDGPU || M == EM_HEXAGON ||
-                   M == EM_PPC || M == EM_PPC64 || M == EM_RISCV ||
-                   M == EM_X86_64;
-
-  // If the output uses REL relocations we must store the dynamic relocation
-  // addends to the output sections. We also store addends for RELA relocations
-  // if --apply-dynamic-relocs is used.
-  // We default to not writing the addends when using RELA relocations since
-  // any standard conforming tool can find it in r_addend.
-  Config->WriteAddends = Args.hasFlag(OPT_apply_dynamic_relocs,
-                                      OPT_no_apply_dynamic_relocs, false) ||
-                         !Config->IsRela;
-
-  Config->TocOptimize =
-      Args.hasFlag(OPT_toc_optimize, OPT_no_toc_optimize, M == EM_PPC64);
-}
-
-// Returns a value of "-format" option.
-static bool isFormatBinary(StringRef S) {
-  if (S == "binary")
-    return true;
-  if (S == "elf" || S == "default")
-    return false;
-  error("unknown -format value: " + S +
-        " (supported formats: elf, default, binary)");
-  return false;
-}
-
-void LinkerDriver::createFiles(opt::InputArgList &Args) {
-  // For --{push,pop}-state.
-  std::vector<std::tuple<bool, bool, bool>> Stack;
-
-  // Iterate over argv to process input files and positional arguments.
-  for (auto *Arg : Args) {
-    switch (Arg->getOption().getUnaliasedOption().getID()) {
-    case OPT_library:
-      addLibrary(Arg->getValue());
-      break;
-    case OPT_INPUT:
-      addFile(Arg->getValue(), /*WithLOption=*/false);
-      break;
-    case OPT_defsym: {
-      StringRef From;
-      StringRef To;
-      std::tie(From, To) = StringRef(Arg->getValue()).split('=');
-      if (From.empty() || To.empty())
-        error("-defsym: syntax error: " + StringRef(Arg->getValue()));
-      else
-        readDefsym(From, MemoryBufferRef(To, "-defsym"));
-      break;
-    }
-    case OPT_script:
-      if (Optional<std::string> Path = searchScript(Arg->getValue())) {
-        if (Optional<MemoryBufferRef> MB = readFile(*Path))
-          readLinkerScript(*MB);
-        break;
-      }
-      error(Twine("cannot find linker script ") + Arg->getValue());
-      break;
-    case OPT_as_needed:
-      Config->AsNeeded = true;
-      break;
-    case OPT_format:
-      Config->FormatBinary = isFormatBinary(Arg->getValue());
-      break;
-    case OPT_no_as_needed:
-      Config->AsNeeded = false;
-      break;
-    case OPT_Bstatic:
-      Config->Static = true;
-      break;
-    case OPT_Bdynamic:
-      Config->Static = false;
-      break;
-    case OPT_whole_archive:
-      InWholeArchive = true;
-      break;
-    case OPT_no_whole_archive:
-      InWholeArchive = false;
-      break;
-    case OPT_just_symbols:
-      if (Optional<MemoryBufferRef> MB = readFile(Arg->getValue())) {
-        Files.push_back(createObjectFile(*MB));
-        Files.back()->JustSymbols = true;
-      }
-      break;
-    case OPT_start_group:
-      if (InputFile::IsInGroup)
-        error("nested --start-group");
-      InputFile::IsInGroup = true;
-      break;
-    case OPT_end_group:
-      if (!InputFile::IsInGroup)
-        error("stray --end-group");
-      InputFile::IsInGroup = false;
-      ++InputFile::NextGroupId;
-      break;
-    case OPT_start_lib:
-      if (InLib)
-        error("nested --start-lib");
-      if (InputFile::IsInGroup)
-        error("may not nest --start-lib in --start-group");
-      InLib = true;
-      InputFile::IsInGroup = true;
-      break;
-    case OPT_end_lib:
-      if (!InLib)
-        error("stray --end-lib");
-      InLib = false;
-      InputFile::IsInGroup = false;
-      ++InputFile::NextGroupId;
-      break;
-    case OPT_push_state:
-      Stack.emplace_back(Config->AsNeeded, Config->Static, InWholeArchive);
-      break;
-    case OPT_pop_state:
-      if (Stack.empty()) {
-        error("unbalanced --push-state/--pop-state");
-        break;
-      }
-      std::tie(Config->AsNeeded, Config->Static, InWholeArchive) = Stack.back();
-      Stack.pop_back();
-      break;
-    }
-  }
-
-  if (Files.empty() && errorCount() == 0)
-    error("no input files");
-}
-
-// If -m <machine_type> was not given, infer it from object files.
-void LinkerDriver::inferMachineType() {
-  if (Config->EKind != ELFNoneKind)
-    return;
-
-  for (InputFile *F : Files) {
-    if (F->EKind == ELFNoneKind)
-      continue;
-    Config->EKind = F->EKind;
-    Config->EMachine = F->EMachine;
-    Config->OSABI = F->OSABI;
-    Config->MipsN32Abi = Config->EMachine == EM_MIPS && isMipsN32Abi(F);
-    return;
-  }
-  error("target emulation unknown: -m or at least one .o file required");
-}
-
-// Parse -z max-page-size=<value>. The default value is defined by
-// each target.
-static uint64_t getMaxPageSize(opt::InputArgList &Args) {
-  uint64_t Val = args::getZOptionValue(Args, OPT_z, "max-page-size",
-                                       Target->DefaultMaxPageSize);
-  if (!isPowerOf2_64(Val))
-    error("max-page-size: value isn't a power of 2");
-  return Val;
-}
-
-// Parses -image-base option.
-static Optional<uint64_t> getImageBase(opt::InputArgList &Args) {
-  // Because we are using "Config->MaxPageSize" here, this function has to be
-  // called after the variable is initialized.
-  auto *Arg = Args.getLastArg(OPT_image_base);
-  if (!Arg)
-    return None;
-
-  StringRef S = Arg->getValue();
-  uint64_t V;
-  if (!to_integer(S, V)) {
-    error("-image-base: number expected, but got " + S);
-    return 0;
-  }
-  if ((V % Config->MaxPageSize) != 0)
-    warn("-image-base: address isn't multiple of page size: " + S);
-  return V;
-}
-
-// Parses `--exclude-libs=lib,lib,...`.
-// The library names may be delimited by commas or colons.
-static DenseSet<StringRef> getExcludeLibs(opt::InputArgList &Args) {
-  DenseSet<StringRef> Ret;
-  for (auto *Arg : Args.filtered(OPT_exclude_libs)) {
-    StringRef S = Arg->getValue();
-    for (;;) {
-      size_t Pos = S.find_first_of(",:");
-      if (Pos == StringRef::npos)
-        break;
-      Ret.insert(S.substr(0, Pos));
-      S = S.substr(Pos + 1);
-    }
-    Ret.insert(S);
-  }
-  return Ret;
-}
-
-// Handles the -exclude-libs option. If a static library file is specified
-// by the -exclude-libs option, all public symbols from the archive become
-// private unless otherwise specified by version scripts or something.
-// A special library name "ALL" means all archive files.
-//
-// This is not a popular option, but some programs such as bionic libc use it.
-template <class ELFT>
-static void excludeLibs(opt::InputArgList &Args) {
-  DenseSet<StringRef> Libs = getExcludeLibs(Args);
-  bool All = Libs.count("ALL");
-
-  auto Visit = [&](InputFile *File) {
-    if (!File->ArchiveName.empty())
-      if (All || Libs.count(path::filename(File->ArchiveName)))
-        for (Symbol *Sym : File->getSymbols())
-          if (!Sym->isLocal() && Sym->File == File)
-            Sym->VersionId = VER_NDX_LOCAL;
-  };
-
-  for (InputFile *File : ObjectFiles)
-    Visit(File);
-
-  for (BitcodeFile *File : BitcodeFiles)
-    Visit(File);
-}
-
-// Force Sym to be entered in the output. Used for -u or equivalent.
-template <class ELFT> static void handleUndefined(StringRef Name) {
-  Symbol *Sym = Symtab->find(Name);
-  if (!Sym)
-    return;
-
-  // Since symbol S may not be used inside the program, LTO may
-  // eliminate it. Mark the symbol as "used" to prevent it.
-  Sym->IsUsedInRegularObj = true;
-
-  if (Sym->isLazy())
-    Symtab->fetchLazy<ELFT>(Sym);
-}
-
-template <class ELFT> static void handleLibcall(StringRef Name) {
-  Symbol *Sym = Symtab->find(Name);
-  if (!Sym || !Sym->isLazy())
-    return;
-
-  MemoryBufferRef MB;
-  if (auto *LO = dyn_cast<LazyObject>(Sym))
-    MB = LO->File->MB;
-  else
-    MB = cast<LazyArchive>(Sym)->getMemberBuffer();
-
-  if (isBitcode(MB))
-    Symtab->fetchLazy<ELFT>(Sym);
-}
-
-// If all references to a DSO happen to be weak, the DSO is not added
-// to DT_NEEDED. If that happens, we need to eliminate shared symbols
-// created from the DSO. Otherwise, they become dangling references
-// that point to a non-existent DSO.
-template <class ELFT> static void demoteSharedSymbols() {
-  for (Symbol *Sym : Symtab->getSymbols()) {
-    if (auto *S = dyn_cast<SharedSymbol>(Sym)) {
-      if (!S->getFile<ELFT>().IsNeeded) {
-        bool Used = S->Used;
-        replaceSymbol<Undefined>(S, nullptr, S->getName(), STB_WEAK, S->StOther,
-                                 S->Type);
-        S->Used = Used;
-      }
-    }
-  }
-}
-
-// The section referred to by S is considered address-significant. Set the
-// KeepUnique flag on the section if appropriate.
-static void markAddrsig(Symbol *S) {
-  if (auto *D = dyn_cast_or_null<Defined>(S))
-    if (D->Section)
-      // We don't need to keep text sections unique under --icf=all even if they
-      // are address-significant.
-      if (Config->ICF == ICFLevel::Safe || !(D->Section->Flags & SHF_EXECINSTR))
-        D->Section->KeepUnique = true;
-}
-
-// Record sections that define symbols mentioned in --keep-unique <symbol>
-// and symbols referred to by address-significance tables. These sections are
-// ineligible for ICF.
-template <class ELFT>
-static void findKeepUniqueSections(opt::InputArgList &Args) {
-  for (auto *Arg : Args.filtered(OPT_keep_unique)) {
-    StringRef Name = Arg->getValue();
-    auto *D = dyn_cast_or_null<Defined>(Symtab->find(Name));
-    if (!D || !D->Section) {
-      warn("could not find symbol " + Name + " to keep unique");
-      continue;
-    }
-    D->Section->KeepUnique = true;
-  }
-
-  // --icf=all --ignore-data-address-equality means that we can ignore
-  // the dynsym and address-significance tables entirely.
-  if (Config->ICF == ICFLevel::All && Config->IgnoreDataAddressEquality)
-    return;
-
-  // Symbols in the dynsym could be address-significant in other executables
-  // or DSOs, so we conservatively mark them as address-significant.
-  for (Symbol *S : Symtab->getSymbols())
-    if (S->includeInDynsym())
-      markAddrsig(S);
-
-  // Visit the address-significance table in each object file and mark each
-  // referenced symbol as address-significant.
-  for (InputFile *F : ObjectFiles) {
-    auto *Obj = cast<ObjFile<ELFT>>(F);
-    ArrayRef<Symbol *> Syms = Obj->getSymbols();
-    if (Obj->AddrsigSec) {
-      ArrayRef<uint8_t> Contents =
-          check(Obj->getObj().getSectionContents(Obj->AddrsigSec));
-      const uint8_t *Cur = Contents.begin();
-      while (Cur != Contents.end()) {
-        unsigned Size;
-        const char *Err;
-        uint64_t SymIndex = decodeULEB128(Cur, &Size, Contents.end(), &Err);
-        if (Err)
-          fatal(toString(F) + ": could not decode addrsig section: " + Err);
-        markAddrsig(Syms[SymIndex]);
-        Cur += Size;
-      }
-    } else {
-      // If an object file does not have an address-significance table,
-      // conservatively mark all of its symbols as address-significant.
-      for (Symbol *S : Syms)
-        markAddrsig(S);
-    }
-  }
-}
-
-template <class ELFT> static Symbol *addUndefined(StringRef Name) {
-  return Symtab->addUndefined<ELFT>(Name, STB_GLOBAL, STV_DEFAULT, 0, false,
-                                    nullptr);
-}
-
-// The --wrap option is a feature to rename symbols so that you can write
-// wrappers for existing functions. If you pass `-wrap=foo`, all
-// occurrences of symbol `foo` are resolved to `wrap_foo` (so, you are
-// expected to write `wrap_foo` function as a wrapper). The original
-// symbol becomes accessible as `real_foo`, so you can call that from your
-// wrapper.
-//
-// This data structure is instantiated for each -wrap option.
-struct WrappedSymbol {
-  Symbol *Sym;
-  Symbol *Real;
-  Symbol *Wrap;
-};
-
-// Handles -wrap option.
-//
-// This function instantiates wrapper symbols. At this point, they seem
-// like they are not being used at all, so we explicitly set some flags so
-// that LTO won't eliminate them.
-template <class ELFT>
-static std::vector<WrappedSymbol> addWrappedSymbols(opt::InputArgList &Args) {
-  std::vector<WrappedSymbol> V;
-  DenseSet<StringRef> Seen;
-
-  for (auto *Arg : Args.filtered(OPT_wrap)) {
-    StringRef Name = Arg->getValue();
-    if (!Seen.insert(Name).second)
-      continue;
-
-    Symbol *Sym = Symtab->find(Name);
-    if (!Sym)
-      continue;
-
-    Symbol *Real = addUndefined<ELFT>(Saver.save("__real_" + Name));
-    Symbol *Wrap = addUndefined<ELFT>(Saver.save("__wrap_" + Name));
-    V.push_back({Sym, Real, Wrap});
-
-    // We want to tell LTO not to inline symbols to be overwritten
-    // because LTO doesn't know the final symbol contents after renaming.
-    Real->CanInline = false;
-    Sym->CanInline = false;
-
-    // Tell LTO not to eliminate these symbols.
-    Sym->IsUsedInRegularObj = true;
-    Wrap->IsUsedInRegularObj = true;
-  }
-  return V;
-}
-
-// Do renaming for -wrap by updating pointers to symbols.
-//
-// When this function is executed, only InputFiles and symbol table
-// contain pointers to symbol objects. We visit them to replace pointers,
-// so that wrapped symbols are swapped as instructed by the command line.
-template <class ELFT> static void wrapSymbols(ArrayRef<WrappedSymbol> Wrapped) {
-  DenseMap<Symbol *, Symbol *> Map;
-  for (const WrappedSymbol &W : Wrapped) {
-    Map[W.Sym] = W.Wrap;
-    Map[W.Real] = W.Sym;
-  }
-
-  // Update pointers in input files.
-  parallelForEach(ObjectFiles, [&](InputFile *File) {
-    std::vector<Symbol *> &Syms = File->getMutableSymbols();
-    for (size_t I = 0, E = Syms.size(); I != E; ++I)
-      if (Symbol *S = Map.lookup(Syms[I]))
-        Syms[I] = S;
-  });
-
-  // Update pointers in the symbol table.
-  for (const WrappedSymbol &W : Wrapped)
-    Symtab->wrap(W.Sym, W.Real, W.Wrap);
-}
-
-static const char *LibcallRoutineNames[] = {
-#define HANDLE_LIBCALL(code, name) name,
-#include "llvm/IR/RuntimeLibcalls.def"
-#undef HANDLE_LIBCALL
-};
-
-// Do actual linking. Note that when this function is called,
-// all linker scripts have already been parsed.
-template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) {
-  Target = getTarget();
-  InX<ELFT>::VerSym = nullptr;
-  InX<ELFT>::VerNeed = nullptr;
-
-  Config->MaxPageSize = getMaxPageSize(Args);
-  Config->ImageBase = getImageBase(Args);
-
-  // If a -hash-style option was not given, set to a default value,
-  // which varies depending on the target.
-  if (!Args.hasArg(OPT_hash_style)) {
-    if (Config->EMachine == EM_MIPS)
-      Config->SysvHash = true;
-    else
-      Config->SysvHash = Config->GnuHash = true;
-  }
-
-  // Default output filename is "a.out" by the Unix tradition.
-  if (Config->OutputFile.empty())
-    Config->OutputFile = "a.out";
-
-  // Fail early if the output file or map file is not writable. If a user has a
-  // long link, e.g. due to a large LTO link, they do not wish to run it and
-  // find that it failed because there was a mistake in their command-line.
-  if (auto E = tryCreateFile(Config->OutputFile))
-    error("cannot open output file " + Config->OutputFile + ": " + E.message());
-  if (auto E = tryCreateFile(Config->MapFile))
-    error("cannot open map file " + Config->MapFile + ": " + E.message());
-  if (errorCount())
-    return;
-
-  // Use default entry point name if no name was given via the command
-  // line nor linker scripts. For some reason, MIPS entry point name is
-  // different from others.
-  Config->WarnMissingEntry =
-      (!Config->Entry.empty() || (!Config->Shared && !Config->Relocatable));
-  if (Config->Entry.empty() && !Config->Relocatable)
-    Config->Entry = (Config->EMachine == EM_MIPS) ? "__start" : "_start";
-
-  // Handle --trace-symbol.
-  for (auto *Arg : Args.filtered(OPT_trace_symbol))
-    Symtab->trace(Arg->getValue());
-
-  // Add all files to the symbol table. This will add almost all
-  // symbols that we need to the symbol table.
-  for (InputFile *F : Files)
-    Symtab->addFile<ELFT>(F);
-
-  // Now that we have every file, we can decide if we will need a
-  // dynamic symbol table.
-  // We need one if we were asked to export dynamic symbols or if we are
-  // producing a shared library.
-  // We also need one if any shared libraries are used and for pie executables
-  // (probably because the dynamic linker needs it).
-  Config->HasDynSymTab =
-      !SharedFiles.empty() || Config->Pic || Config->ExportDynamic;
-
-  // Some symbols (such as __ehdr_start) are defined lazily only when there
-  // are undefined symbols for them, so we add these to trigger that logic.
-  for (StringRef Name : Script->ReferencedSymbols)
-    addUndefined<ELFT>(Name);
-
-  // Handle the `--undefined <sym>` options.
-  for (StringRef S : Config->Undefined)
-    handleUndefined<ELFT>(S);
-
-  // If an entry symbol is in a static archive, pull out that file now.
-  handleUndefined<ELFT>(Config->Entry);
-
-  // If any of our inputs are bitcode files, the LTO code generator may create
-  // references to certain library functions that might not be explicit in the
-  // bitcode file's symbol table. If any of those library functions are defined
-  // in a bitcode file in an archive member, we need to arrange to use LTO to
-  // compile those archive members by adding them to the link beforehand.
-  //
-  // However, adding all libcall symbols to the link can have undesired
-  // consequences. For example, the libgcc implementation of
-  // __sync_val_compare_and_swap_8 on 32-bit ARM pulls in an .init_array entry
-  // that aborts the program if the Linux kernel does not support 64-bit
-  // atomics, which would prevent the program from running even if it does not
-  // use 64-bit atomics.
-  //
-  // Therefore, we only add libcall symbols to the link before LTO if we have
-  // to, i.e. if the symbol's definition is in bitcode. Any other required
-  // libcall symbols will be added to the link after LTO when we add the LTO
-  // object file to the link.
-  if (!BitcodeFiles.empty())
-    for (const char *S : LibcallRoutineNames)
-      handleLibcall<ELFT>(S);
-
-  // Return if there were name resolution errors.
-  if (errorCount())
-    return;
-
-  // Now when we read all script files, we want to finalize order of linker
-  // script commands, which can be not yet final because of INSERT commands.
-  Script->processInsertCommands();
-
-  // We want to declare linker script's symbols early,
-  // so that we can version them.
-  // They also might be exported if referenced by DSOs.
-  Script->declareSymbols();
-
-  // Handle the -exclude-libs option.
-  if (Args.hasArg(OPT_exclude_libs))
-    excludeLibs<ELFT>(Args);
-
-  // Create ElfHeader early. We need a dummy section in
-  // addReservedSymbols to mark the created symbols as not absolute.
-  Out::ElfHeader = make<OutputSection>("", 0, SHF_ALLOC);
-  Out::ElfHeader->Size = sizeof(typename ELFT::Ehdr);
-
-  // Create wrapped symbols for -wrap option.
-  std::vector<WrappedSymbol> Wrapped = addWrappedSymbols<ELFT>(Args);
-
-  // We need to create some reserved symbols such as _end. Create them.
-  if (!Config->Relocatable)
-    addReservedSymbols();
-
-  // Apply version scripts.
-  //
-  // For a relocatable output, version scripts don't make sense, and
-  // parsing a symbol version string (e.g. dropping "@ver1" from a symbol
-  // name "foo@ver1") rather do harm, so we don't call this if -r is given.
-  if (!Config->Relocatable)
-    Symtab->scanVersionScript();
-
-  // Do link-time optimization if given files are LLVM bitcode files.
-  // This compiles bitcode files into real object files.
-  //
-  // With this the symbol table should be complete. After this, no new names
-  // except a few linker-synthesized ones will be added to the symbol table.
-  Symtab->addCombinedLTOObject<ELFT>();
-  if (errorCount())
-    return;
-
-  // If -thinlto-index-only is given, we should create only "index
-  // files" and not object files. Index file creation is already done
-  // in addCombinedLTOObject, so we are done if that's the case.
-  if (Config->ThinLTOIndexOnly)
-    return;
-
-  // Likewise, --plugin-opt=emit-llvm is an option to make LTO create
-  // an output file in bitcode and exit, so that you can just get a
-  // combined bitcode file.
-  if (Config->EmitLLVM)
-    return;
-
-  // Apply symbol renames for -wrap.
-  if (!Wrapped.empty())
-    wrapSymbols<ELFT>(Wrapped);
-
-  // Now that we have a complete list of input files.
-  // Beyond this point, no new files are added.
-  // Aggregate all input sections into one place.
-  for (InputFile *F : ObjectFiles)
-    for (InputSectionBase *S : F->getSections())
-      if (S && S != &InputSection::Discarded)
-        InputSections.push_back(S);
-  for (BinaryFile *F : BinaryFiles)
-    for (InputSectionBase *S : F->getSections())
-      InputSections.push_back(cast<InputSection>(S));
-
-  // We do not want to emit debug sections if --strip-all
-  // or -strip-debug are given.
-  if (Config->Strip != StripPolicy::None)
-    llvm::erase_if(InputSections, [](InputSectionBase *S) {
-      return S->Name.startswith(".debug") || S->Name.startswith(".zdebug");
-    });
-
-  Config->EFlags = Target->calcEFlags();
-
-  if (Config->EMachine == EM_ARM) {
-    // FIXME: These warnings can be removed when lld only uses these features
-    // when the input objects have been compiled with an architecture that
-    // supports them.
-    if (Config->ARMHasBlx == false)
-      warn("lld uses blx instruction, no object with architecture supporting "
-           "feature detected");
-  }
-
-  // This adds a .comment section containing a version string. We have to add it
-  // before mergeSections because the .comment section is a mergeable section.
-  if (!Config->Relocatable)
-    InputSections.push_back(createCommentSection());
-
-  // Do size optimizations: garbage collection, merging of SHF_MERGE sections
-  // and identical code folding.
-  splitSections<ELFT>();
-  markLive<ELFT>();
-  demoteSharedSymbols<ELFT>();
-  mergeSections();
-  if (Config->ICF != ICFLevel::None) {
-    findKeepUniqueSections<ELFT>(Args);
-    doIcf<ELFT>();
-  }
-
-  // Read the callgraph now that we know what was gced or icfed
-  if (Config->CallGraphProfileSort) {
-    if (auto *Arg = Args.getLastArg(OPT_call_graph_ordering_file))
-      if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
-        readCallGraph(*Buffer);
-    readCallGraphsFromObjectFiles<ELFT>();
-  }
-
-  // Write the result to the file.
-  writeResult<ELFT>();
-}