[dsymutil] Tablegenify option parsing

[JDevlieghere]

Summary

This patch reimplements command line option parsing in dsymutil with Tablegen and libOption. The main motivation for this change is to prevent clashes with other cl::opt options defined in llvm. Although it's a bit more heavyweight, it has some nice advantages such as no global static initializers and better separation between the code and the option definitions.

I also used this opportunity to improve how dsymutil deals with incompatible options. Instead of having checks spread across the code, everything is now grouped together in verifyOptions. The fact that the options are no longer global means that we need to pass them around a bit more, but I think it's worth the tradeoff.

[thegameg]

I noticed a bunch of explicit llvm:: prefixes like llvm::Error, llvm::StringRef, etc. Did you intentionally leave that there?

Otherwise, this LGTM, thanks for the nice cleanup!

llvm/tools/dsymutil/dsymutil.cpp

161 ↗

(On Diff #222934)

Would it make sense for all these error codes to be std::errc::invalid_argument?

233 ↗

(On Diff #222934)

= std::move(*InputFiles);?

[friss]

This seems a little heavyweight, but it reads nicely and gets rid of global state. Go for it.

[JDevlieghere]

In D68361#1692988, @thegameg wrote:

I noticed a bunch of explicit llvm:: prefixes like llvm::Error, llvm::StringRef, etc. Did you intentionally leave that there?

No, that's definitely unintentional. I'll fix the inconsistency in a follow-up commit! :-)

llvm/trunk/test/tools/dsymutil/cmdline.test

 RUN: dsymutil -help 2>&1 | FileCheck --check-prefix=HELP %s
 HELP: OVERVIEW: manipulate archived DWARF debug symbol files.
-HELP: USAGE: dsymutil{{[^ ]*}} [options] <input files>
+HELP: USAGE: {{.*}}dsymutil{{[^ ]*}} [options] <input files>
 HELP-NOT: -reverse-iterate
-HELP: Color Options
-HELP: -color
-HELP: Specific Options:
+HELP: Dsymutil Options:
 HELP: -accelerator
-HELP: -arch=<arch>
+HELP: -arch <arch>
 HELP: -dump-debug-map
 HELP: -flat
 HELP: -minimize
 HELP: -no-odr
 HELP: -no-output
 HELP: -no-swiftmodule-timestamp
-HELP: -num-threads=<n>
-HELP: -o=<filename>
-HELP: -oso-prepend-path=<path>
+HELP: -num-threads <threads>
+HELP: -oso-prepend-path <path>
+HELP: -o <filename>
 HELP: -papertrail
 HELP: -symbol-map
 HELP: -symtab
 HELP: -toolchain
 HELP: -update
 HELP: -verbose
 HELP: -verify
 HELP: -y
 HELP-NOT: -reverse-iterate
 
 RUN: dsymutil --version 2>&1 | FileCheck --check-prefix=VERSION %s
 VERSION: {{ version }}

llvm/trunk/tools/dsymutil/CMakeLists.txt

+set(LLVM_TARGET_DEFINITIONS Options.td)
+tablegen(LLVM Options.inc -gen-opt-parser-defs)
+add_public_tablegen_target(DsymutilTableGen)
+
 set(LLVM_LINK_COMPONENTS
   AllTargetsAsmPrinters
   AllTargetsCodeGens
   AllTargetsDescs
   AllTargetsInfos
   AsmPrinter
   DebugInfoDWARF
   MC
   Object
+  Option
   Support
   Target
   )
 
 add_llvm_tool(dsymutil
   dsymutil.cpp
   BinaryHolder.cpp
   CFBundle.cpp
   CompileUnit.cpp
   DebugMap.cpp
   DeclContext.cpp
   DwarfLinker.cpp
   DwarfStreamer.cpp
   MachODebugMapParser.cpp
   MachOUtils.cpp
   NonRelocatableStringpool.cpp
   SymbolMap.cpp
 
   DEPENDS
   intrinsics_gen
+  ${tablegen_deps}
   )
 
 if(APPLE)
   target_link_libraries(dsymutil PRIVATE "-framework CoreFoundation")
 endif(APPLE)

llvm/trunk/tools/dsymutil/Options.td

+include "llvm/Option/OptParser.td"
+
+class F<string name>: Flag<["--", "-"], name>;
+
+def grp_general : OptionGroup<"Dsymutil">, HelpText<"Dsymutil Options">;
+
+def help: F<"help">,
+  HelpText<"Prints this help output.">,
+  Group<grp_general>;
+def: Flag<["-"], "h">,
+  Alias<help>,
+  HelpText<"Alias for --help">,
+  Group<grp_general>;
+
+def version: F<"version">,
+  HelpText<"Prints the dsymutil version.">,
+  Group<grp_general>;
+def: Flag<["-"], "v">,
+  Alias<version>,
+  HelpText<"Alias for --version">,
+  Group<grp_general>;
+
+def verbose: F<"verbose">,
+  HelpText<"Enable verbose mode.">,
+  Group<grp_general>;
+
+def verify: F<"verify">,
+  HelpText<"Run the DWARF verifier on the linked DWARF debug info.">,
+  Group<grp_general>;
+
+def no_output: F<"no-output">,
+  HelpText<"Do the link in memory, but do not emit the result file.">,
+  Group<grp_general>;
+
+def no_swiftmodule_timestamp: F<"no-swiftmodule-timestamp">,
+  HelpText<"Don't check timestamp for swiftmodule files.">,
+  Group<grp_general>;
+
+def no_odr: F<"no-odr">,
+  HelpText<"Do not use ODR (One Definition Rule) for type uniquing.">,
+  Group<grp_general>;
+
+def dump_debug_map: F<"dump-debug-map">,
+  HelpText<"Parse and dump the debug map to standard output. Not DWARF link will take place.">,
+  Group<grp_general>;
+
+def yaml_input: F<"y">,
+  HelpText<"Treat the input file is a YAML debug map rather than a binary.">,
+  Group<grp_general>;
+
+def papertrail: F<"papertrail">,
+  HelpText<"Embed warnings in the linked DWARF debug info.">,
+  Group<grp_general>;
+
+def assembly: F<"S">,
+  HelpText<"Output textual assembly instead of a binary dSYM companion file.">,
+  Group<grp_general>;
+
+def symtab: F<"symtab">,
+  HelpText<"Dumps the symbol table found in executable or object file(s) and exits.">,
+  Group<grp_general>;
+def: Flag<["-"], "s">,
+  Alias<symtab>,
+  HelpText<"Alias for --symtab">,
+  Group<grp_general>;
+
+def flat: F<"flat">,
+  HelpText<"Produce a flat dSYM file (not a bundle).">,
+  Group<grp_general>;
+def: Flag<["-"], "f">,
+  Alias<flat>,
+  HelpText<"Alias for --flat">,
+  Group<grp_general>;
+
+def minimize: F<"minimize">,
+  HelpText<"When used when creating a dSYM file with Apple accelerator tables, "
+           "this option will suppress the emission of the .debug_inlines, "
+           ".debug_pubnames, and .debug_pubtypes sections since dsymutil "
+           "has better equivalents: .apple_names and .apple_types. When used in "
+           "conjunction with --update option, this option will cause redundant "
+           "accelerator tables to be removed.">,
+  Group<grp_general>;
+def: Flag<["-"], "z">,
+  Alias<minimize>,
+  HelpText<"Alias for --minimize">,
+  Group<grp_general>;
+
+def update: F<"update">,
+  HelpText<"Updates existing dSYM files to contain the latest accelerator tables and other DWARF optimizations.">,
+  Group<grp_general>;
+def: Flag<["-"], "u">,
+  Alias<update>,
+  HelpText<"Alias for --update">,
+  Group<grp_general>;
+
+def output: Separate<["--", "-"], "o">,
+  MetaVarName<"<filename>">,
+  HelpText<"Specify the output file. Defaults to <input file>.dwarf">,
+  Group<grp_general>;
+def: Separate<["-"], "out">,
+  Alias<output>,
+  HelpText<"Alias for --o">,
+  Group<grp_general>;
+def: Joined<["--", "-"], "out=">, Alias<output>;
+def: Joined<["--", "-"], "o=">, Alias<output>;
+
+def oso_prepend_path: Separate<["--", "-"], "oso-prepend-path">,
+  MetaVarName<"<path>">,
+  HelpText<"Specify a directory to prepend to the paths of object files.">,
+  Group<grp_general>;
+def: Joined<["--", "-"], "oso-prepend-path=">, Alias<oso_prepend_path>;
+
+def symbolmap: Separate<["--", "-"], "symbol-map">,
+  MetaVarName<"<bcsymbolmap>">,
+  HelpText<"Updates the existing dSYMs inplace using symbol map specified.">,
+  Group<grp_general>;
+def: Joined<["--", "-"], "symbol-map=">, Alias<symbolmap>;
+
+def arch: Separate<["--", "-"], "arch">,
+  MetaVarName<"<arch>">,
+  HelpText<"Link DWARF debug information only for specified CPU architecture"
+           "types. This option can be specified multiple times, once for each"
+           "desired architecture. All CPU architectures will be linked by"
+           "default.">,
+  Group<grp_general>;
+def: Joined<["--", "-"], "arch=">, Alias<arch>;
+
+def accelerator: Separate<["--", "-"], "accelerator">,
+  MetaVarName<"<accelerator type>">,
+  HelpText<"Specify the desired type of accelerator table. Valid options are 'Apple', 'Dwarf' and 'Default'">,
+  Group<grp_general>;
+def: Joined<["--", "-"], "accelerator=">, Alias<accelerator>;
+
+def toolchain: Separate<["--", "-"], "toolchain">,
+  MetaVarName<"<toolchain>">,
+  HelpText<"Embed toolchain information in dSYM bundle.">,
+  Group<grp_general>;
+
+def threads: Separate<["--", "-"], "num-threads">,
+  MetaVarName<"<threads>">,
+  HelpText<"Specifies the maximum number of simultaneous threads to use when linking multiple architectures.">,
+  Group<grp_general>;
+def: Separate<["-"], "j">,
+  Alias<threads>,
+  HelpText<"Alias for --num-threads">,
+  Group<grp_general>;

llvm/trunk/tools/dsymutil/dsymutil.cpp

 #include "CFBundle.h"
 #include "DebugMap.h"
 #include "LinkUtils.h"
 #include "MachOUtils.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/DebugInfo/DIContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFVerifier.h"
 #include "llvm/Object/Binary.h"
 #include "llvm/Object/MachO.h"
+#include "llvm/Option/Arg.h"
+#include "llvm/Option/ArgList.h"
+#include "llvm/Option/Option.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/ThreadPool.h"
 #include "llvm/Support/WithColor.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/thread.h"
 #include <algorithm>
 #include <cstdint>
 #include <cstdlib>
 #include <string>
 #include <system_error>
 
 using namespace llvm;
-using namespace llvm::cl;
 using namespace llvm::dsymutil;
 using namespace object;
 
-static OptionCategory DsymCategory("Specific Options");
-static opt<bool> Help("h", desc("Alias for -help"), Hidden);
-static opt<bool> Version("v", desc("Alias for -version"), Hidden);
-
-static list<std::string> InputFiles(Positional, OneOrMore,
-                                    desc("<input files>"), cat(DsymCategory));
-
-static opt<std::string>
-    OutputFileOpt("o",
-                  desc("Specify the output file. default: <input file>.dwarf"),
-                  value_desc("filename"), cat(DsymCategory));
-static alias OutputFileOptA("out", desc("Alias for -o"),
-                            aliasopt(OutputFileOpt));
-
-static opt<std::string> OsoPrependPath(
-    "oso-prepend-path",
-    desc("Specify a directory to prepend to the paths of object files."),
-    value_desc("path"), cat(DsymCategory));
-
-static opt<bool> Assembly(
-    "S",
-    desc("Output textual assembly instead of a binary dSYM companion file."),
-    init(false), cat(DsymCategory), cl::Hidden);
-
-static opt<bool> DumpStab(
-    "symtab",
-    desc("Dumps the symbol table found in executable or object file(s) and\n"
-         "exits."),
-    init(false), cat(DsymCategory));
-static alias DumpStabA("s", desc("Alias for --symtab"), aliasopt(DumpStab));
-
-static opt<bool> FlatOut("flat",
-                         desc("Produce a flat dSYM file (not a bundle)."),
-                         init(false), cat(DsymCategory));
-static alias FlatOutA("f", desc("Alias for --flat"), aliasopt(FlatOut));
-
-static opt<bool> Minimize(
-    "minimize",
-    desc("When used when creating a dSYM file with Apple accelerator tables,\n"
-         "this option will suppress the emission of the .debug_inlines, \n"
-         ".debug_pubnames, and .debug_pubtypes sections since dsymutil \n"
-         "has better equivalents: .apple_names and .apple_types. When used in\n"
-         "conjunction with --update option, this option will cause redundant\n"
-         "accelerator tables to be removed."),
-    init(false), cat(DsymCategory));
-static alias MinimizeA("z", desc("Alias for --minimize"), aliasopt(Minimize));
-
-static opt<bool> Update(
-    "update",
-    desc("Updates existing dSYM files to contain the latest accelerator\n"
-         "tables and other DWARF optimizations."),
-    init(false), cat(DsymCategory));
-static alias UpdateA("u", desc("Alias for --update"), aliasopt(Update));
-
-static opt<std::string> SymbolMap(
-    "symbol-map",
-    desc("Updates the existing dSYMs inplace using symbol map specified."),
-    value_desc("bcsymbolmap"), cat(DsymCategory));
-
-static cl::opt<AccelTableKind> AcceleratorTable(
-    "accelerator", cl::desc("Output accelerator tables."),
-    cl::values(clEnumValN(AccelTableKind::Default, "Default",
-                          "Default for input."),
-               clEnumValN(AccelTableKind::Apple, "Apple", "Apple"),
-               clEnumValN(AccelTableKind::Dwarf, "Dwarf", "DWARF")),
-    cl::init(AccelTableKind::Default), cat(DsymCategory));
-
-static opt<unsigned> NumThreads(
-    "num-threads",
-    desc("Specifies the maximum number (n) of simultaneous threads to use\n"
-         "when linking multiple architectures."),
-    value_desc("n"), init(0), cat(DsymCategory));
-static alias NumThreadsA("j", desc("Alias for --num-threads"),
-                         aliasopt(NumThreads));
-
-static opt<bool> Verbose("verbose", desc("Verbosity level"), init(false),
-                         cat(DsymCategory));
-
-static opt<bool>
-    NoOutput("no-output",
-             desc("Do the link in memory, but do not emit the result file."),
-             init(false), cat(DsymCategory));
-
-static opt<bool>
-    NoTimestamp("no-swiftmodule-timestamp",
-                desc("Don't check timestamp for swiftmodule files."),
-                init(false), cat(DsymCategory));
-
-static list<std::string> ArchFlags(
-    "arch",
-    desc("Link DWARF debug information only for specified CPU architecture\n"
-         "types. This option can be specified multiple times, once for each\n"
-         "desired architecture. All CPU architectures will be linked by\n"
-         "default."),
-    value_desc("arch"), ZeroOrMore, cat(DsymCategory));
-
-static opt<bool>
-    NoODR("no-odr",
-          desc("Do not use ODR (One Definition Rule) for type uniquing."),
-          init(false), cat(DsymCategory));
-
-static opt<bool> DumpDebugMap(
-    "dump-debug-map",
-    desc("Parse and dump the debug map to standard output. Not DWARF link "
-         "will take place."),
-    init(false), cat(DsymCategory));
-
-static opt<bool> InputIsYAMLDebugMap(
-    "y", desc("Treat the input file is a YAML debug map rather than a binary."),
-    init(false), cat(DsymCategory));
-
-static opt<bool> Verify("verify", desc("Verify the linked DWARF debug info."),
-                        cat(DsymCategory));
-
-static opt<std::string>
-    Toolchain("toolchain", desc("Embed toolchain information in dSYM bundle."),
-              cat(DsymCategory));
-
-static opt<bool>
-    PaperTrailWarnings("papertrail",
-                       desc("Embed warnings in the linked DWARF debug info."),
-                       cat(DsymCategory));
+namespace {
+enum ID {
+  OPT_INVALID = 0, // This is not an option ID.
+#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
+               HELPTEXT, METAVAR, VALUES)                                      \
+  OPT_##ID,
+#include "Options.inc"
+#undef OPTION
+};
+
+#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
+#include "Options.inc"
+#undef PREFIX
+
+const opt::OptTable::Info InfoTable[] = {
+#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
+               HELPTEXT, METAVAR, VALUES)                                      \
+  {                                                                            \
+      PREFIX,      NAME,      HELPTEXT,                                        \
+      METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
+      PARAM,       FLAGS,     OPT_##GROUP,                                     \
+      OPT_##ALIAS, ALIASARGS, VALUES},
+#include "Options.inc"
+#undef OPTION
+};
+
+class DsymutilOptTable : public opt::OptTable {
+public:
+  DsymutilOptTable() : OptTable(InfoTable) {}
+};
+} // namespace
+
+struct DsymutilOptions {
+  bool DumpDebugMap = false;
+  bool DumpStab = false;
+  bool Flat = false;
+  bool InputIsYAMLDebugMap = false;
+  bool PaperTrailWarnings = false;
+  bool Verify = false;
+  std::string SymbolMap;
+  std::string OutputFile;
+  std::string Toolchain;
+  std::vector<std::string> Archs;
+  std::vector<std::string> InputFiles;
+  unsigned NumThreads;
+  LinkOptions LinkOptions;
+};
+
+/// Return a list of input files. This function has logic for dealing with the
+/// special case where we might have dSYM bundles as input. The function
+/// returns an error when the directory structure doesn't match that of a dSYM
+/// bundle.
+static Expected<std::vector<std::string>> getInputs(opt::InputArgList &Args,
+                                                    bool DsymAsInput) {
+  std::vector<std::string> InputFiles;
+  for (auto *File : Args.filtered(OPT_INPUT))
+    InputFiles.push_back(File->getValue());
+
+  if (!DsymAsInput)
+    return InputFiles;
+
+  // If we are updating, we might get dSYM bundles as input.
+  std::vector<std::string> Inputs;
+  for (const auto &Input : InputFiles) {
+    if (!llvm::sys::fs::is_directory(Input)) {
+      Inputs.push_back(Input);
+      continue;
+    }
+
+    // Make sure that we're dealing with a dSYM bundle.
+    SmallString<256> BundlePath(Input);
+    sys::path::append(BundlePath, "Contents", "Resources", "DWARF");
+    if (!llvm::sys::fs::is_directory(BundlePath))
+      return make_error<StringError>(
+          Input + " is a directory, but doesn't look like a dSYM bundle.",
+          inconvertibleErrorCode());
+
+    // Create a directory iterator to iterate over all the entries in the
+    // bundle.
+    std::error_code EC;
+    llvm::sys::fs::directory_iterator DirIt(BundlePath, EC);
+    llvm::sys::fs::directory_iterator DirEnd;
+    if (EC)
+      return errorCodeToError(EC);
+
+    // Add each entry to the list of inputs.
+    while (DirIt != DirEnd) {
+      Inputs.push_back(DirIt->path());
+      DirIt.increment(EC);
+      if (EC)
+        return errorCodeToError(EC);
+    }
+  }
+  return Inputs;
+}
+
+// Verify that the given combination of options makes sense.
+static llvm::Error verifyOptions(const DsymutilOptions &Options) {
+  if (Options.LinkOptions.Update &&
+      std::find(Options.InputFiles.begin(), Options.InputFiles.end(), "-") !=
+          Options.InputFiles.end()) {
+    // FIXME: We cannot use stdin for an update because stdin will be
+    // consumed by the BinaryHolder during the debugmap parsing, and
+    // then we will want to consume it again in DwarfLinker. If we
+    // used a unique BinaryHolder object that could cache multiple
+    // binaries this restriction would go away.
+    return make_error<StringError>(
+        "standard input cannot be used as input for a dSYM update.",
+        errc::invalid_argument);
+  }
+
+  if (!Options.Flat && Options.OutputFile == "-")
+    return make_error<StringError>(
+        "cannot emit to standard output without --flat.",
+        errc::invalid_argument);
+
+  if (Options.InputFiles.size() > 1 && Options.Flat &&
+      !Options.OutputFile.empty())
+    return make_error<StringError>(
+        "cannot use -o with multiple inputs in flat mode.",
+        errc::invalid_argument);
+
+  if (Options.PaperTrailWarnings && Options.InputIsYAMLDebugMap)
+    return make_error<StringError>(
+        "paper trail warnings are not supported for YAML input.",
+        errc::invalid_argument);
 
-static Error createPlistFile(llvm::StringRef Bin, llvm::StringRef BundleRoot) {
-  if (NoOutput)
-    return Error::success();
+}
+
+static Expected<AccelTableKind> getAccelTableKind(opt::InputArgList &Args) {
+  if (opt::Arg *Accelerator = Args.getLastArg(OPT_accelerator)) {
+    StringRef S = Accelerator->getValue();
+    if (S == "Apple")
+      return AccelTableKind::Apple;
+    if (S == "Dwarf")
+      return AccelTableKind::Dwarf;
+    if (S == "Default")
+      return AccelTableKind::Default;
+    return make_error<StringError>(
+        "invalid accelerator type specified: '" + S +
+            "'. Support values are 'Apple', 'Dwarf' and 'Default'.",
+        inconvertibleErrorCode());
+  }
+  return AccelTableKind::Default;
+}
+
+/// Parses the command line options into the LinkOptions struct and performs
+/// some sanity checking. Returns an error in case the latter fails.
+static Expected<DsymutilOptions> getOptions(opt::InputArgList &Args) {
+  DsymutilOptions Options;
+
+  Options.DumpDebugMap = Args.hasArg(OPT_dump_debug_map);
+  Options.DumpStab = Args.hasArg(OPT_symtab);
+  Options.Flat = Args.hasArg(OPT_flat);
+  Options.InputIsYAMLDebugMap = Args.hasArg(OPT_yaml_input);
+  Options.PaperTrailWarnings = Args.hasArg(OPT_papertrail);
+  Options.Verify = Args.hasArg(OPT_verify);
+
+  Options.LinkOptions.Minimize = Args.hasArg(OPT_minimize);
+  Options.LinkOptions.NoODR = Args.hasArg(OPT_no_odr);
+  Options.LinkOptions.NoOutput = Args.hasArg(OPT_no_output);
+  Options.LinkOptions.NoTimestamp = Args.hasArg(OPT_no_swiftmodule_timestamp);
+  Options.LinkOptions.Update = Args.hasArg(OPT_update);
+  Options.LinkOptions.Verbose = Args.hasArg(OPT_verbose);
 
+  if (Expected<AccelTableKind> AccelKind = getAccelTableKind(Args)) {
+    Options.LinkOptions.TheAccelTableKind = *AccelKind;
+  } else {
+    return AccelKind.takeError();
+  }
+
+  if (opt::Arg *SymbolMap = Args.getLastArg(OPT_symbolmap))
+    Options.SymbolMap = SymbolMap->getValue();
+
+  if (Args.hasArg(OPT_symbolmap))
+    Options.LinkOptions.Update = true;
+
+  if (Expected<std::vector<std::string>> InputFiles =
+          getInputs(Args, Options.LinkOptions.Update)) {
+    Options.InputFiles = std::move(*InputFiles);
+  } else {
+    return InputFiles.takeError();
+  }
+
+  for (auto *Arch : Args.filtered(OPT_arch))
+    Options.Archs.push_back(Arch->getValue());
+
+  if (opt::Arg *OsoPrependPath = Args.getLastArg(OPT_oso_prepend_path))
+    Options.LinkOptions.PrependPath = OsoPrependPath->getValue();
+
+  if (opt::Arg *OutputFile = Args.getLastArg(OPT_output))
+    Options.OutputFile = OutputFile->getValue();
+
+  if (opt::Arg *Toolchain = Args.getLastArg(OPT_toolchain))
+    Options.Toolchain = Toolchain->getValue();
+
+  if (Args.hasArg(OPT_assembly))
+    Options.LinkOptions.FileType = OutputFileType::Assembly;
+
+  if (opt::Arg *NumThreads = Args.getLastArg(OPT_threads))
+    Options.LinkOptions.Threads = atoi(NumThreads->getValue());
+  else
+    Options.LinkOptions.Threads = llvm::thread::hardware_concurrency();
+
+  if (Options.DumpDebugMap || Options.LinkOptions.Verbose)
+    Options.LinkOptions.Threads = 1;
+
+  if (getenv("RC_DEBUG_OPTIONS"))
+    Options.PaperTrailWarnings = true;
+
+  if (Error E = verifyOptions(Options))
+    return std::move(E);
+  return Options;
+}
+
+static Error createPlistFile(llvm::StringRef Bin, llvm::StringRef BundleRoot,
+                             llvm::StringRef Toolchain) {
   // Create plist file to write to.
   llvm::SmallString<128> InfoPlist(BundleRoot);
   llvm::sys::path::append(InfoPlist, "Contents/Info.plist");
   std::error_code EC;
   llvm::raw_fd_ostream PL(InfoPlist, EC, llvm::sys::fs::OF_Text);
   if (EC)
     return make_error<StringError>(
         "cannot create Plist: " + toString(errorCodeToError(EC)), EC);
static Error createPlistFile(llvm::StringRef Bin, llvm::StringRef BundleRoot,
   PL << "\t</dict>\n"
      << "</plist>\n";
 
   PL.close();
   return Error::success();
 }
 
 static Error createBundleDir(llvm::StringRef BundleBase) {
-  if (NoOutput)
-    return Error::success();
-
   llvm::SmallString<128> Bundle(BundleBase);
   llvm::sys::path::append(Bundle, "Contents", "Resources", "DWARF");
   if (std::error_code EC =
           create_directories(Bundle.str(), true, llvm::sys::fs::perms::all_all))
     return make_error<StringError>(
         "cannot create bundle: " + toString(errorCodeToError(EC)), EC);
 
   return Error::success();
 }
 
-static bool verify(llvm::StringRef OutputFile, llvm::StringRef Arch) {
+static bool verify(llvm::StringRef OutputFile, llvm::StringRef Arch,
+                   bool Verbose) {
   if (OutputFile == "-") {
     WithColor::warning() << "verification skipped for " << Arch
                          << "because writing to stdout.\n";
     return true;
   }
 
   Expected<OwningBinary<Binary>> BinOrErr = createBinary(OutputFile);
   if (!BinOrErr) {
struct OutputLocation {
   OutputLocation(std::string DWARFFile,
                  llvm::Optional<std::string> ResourceDir = {})
       : DWARFFile(DWARFFile), ResourceDir(ResourceDir) {}
   /// This method is a workaround for older compilers.
   llvm::Optional<std::string> getResourceDir() const { return ResourceDir; }
   std::string DWARFFile;
   llvm::Optional<std::string> ResourceDir;
 };
-}
+} // namespace
 
-static Expected<OutputLocation> getOutputFileName(llvm::StringRef InputFile) {
-  if (OutputFileOpt == "-")
-    return OutputLocation(OutputFileOpt);
+static Expected<OutputLocation>
+getOutputFileName(llvm::StringRef InputFile, const DsymutilOptions &Options) {
+  if (Options.OutputFile == "-")
+    return OutputLocation(Options.OutputFile);
 
   // When updating, do in place replacement.
-  if (OutputFileOpt.empty() && (Update || !SymbolMap.empty()))
+  if (Options.OutputFile.empty() &&
+      (Options.LinkOptions.Update || !Options.SymbolMap.empty()))
     return OutputLocation(InputFile);
 
   // If a flat dSYM has been requested, things are pretty simple.
-  if (FlatOut) {
-    if (OutputFileOpt.empty()) {
+  if (Options.Flat) {
+    if (Options.OutputFile.empty()) {
       if (InputFile == "-")
         return OutputLocation{"a.out.dwarf", {}};
       return OutputLocation((InputFile + ".dwarf").str());
     }
 
-    return OutputLocation(OutputFileOpt);
+    return OutputLocation(Options.OutputFile);
   }
 
   // We need to create/update a dSYM bundle.
   // A bundle hierarchy looks like this:
   //   <bundle name>.dSYM/
   //       Contents/
   //          Info.plist
   //          Resources/
   //             DWARF/
   //                <DWARF file(s)>
   std::string DwarfFile =
       InputFile == "-" ? llvm::StringRef("a.out") : InputFile;
-  llvm::SmallString<128> Path(OutputFileOpt);
+  llvm::SmallString<128> Path(Options.OutputFile);
   if (Path.empty())
     Path = DwarfFile + ".dSYM";
+  if (!Options.LinkOptions.NoOutput) {
     if (auto E = createBundleDir(Path))
       return std::move(E);
-  if (auto E = createPlistFile(DwarfFile, Path))
+    if (auto E = createPlistFile(DwarfFile, Path, Options.Toolchain))
       return std::move(E);
+  }
 
   llvm::sys::path::append(Path, "Contents", "Resources");
   std::string ResourceDir = Path.str();
   llvm::sys::path::append(Path, "DWARF", llvm::sys::path::filename(DwarfFile));
   return OutputLocation(Path.str(), ResourceDir);
 }
 
-/// Parses the command line options into the LinkOptions struct and performs
-/// some sanity checking. Returns an error in case the latter fails.
-static Expected<LinkOptions> getOptions() {
-  LinkOptions Options;
-
-  Options.Verbose = Verbose;
-  Options.NoOutput = NoOutput;
-  Options.NoODR = NoODR;
-  Options.Minimize = Minimize;
-  Options.Update = Update;
-  Options.NoTimestamp = NoTimestamp;
-  Options.PrependPath = OsoPrependPath;
-  Options.TheAccelTableKind = AcceleratorTable;
-
-  if (!SymbolMap.empty())
-    Options.Update = true;
-
-  if (Assembly)
-    Options.FileType = OutputFileType::Assembly;
-
-  if (Options.Update && std::find(InputFiles.begin(), InputFiles.end(), "-") !=
-                            InputFiles.end()) {
-    // FIXME: We cannot use stdin for an update because stdin will be
-    // consumed by the BinaryHolder during the debugmap parsing, and
-    // then we will want to consume it again in DwarfLinker. If we
-    // used a unique BinaryHolder object that could cache multiple
-    // binaries this restriction would go away.
-    return make_error<StringError>(
-        "standard input cannot be used as input for a dSYM update.",
-        inconvertibleErrorCode());
-  }
-
-  if (NumThreads == 0)
-    Options.Threads = llvm::thread::hardware_concurrency();
-  else
-    Options.Threads = NumThreads;
-  if (DumpDebugMap || Verbose)
-    Options.Threads = 1;
-
-  return Options;
-}
-
-/// Return a list of input files. This function has logic for dealing with the
-/// special case where we might have dSYM bundles as input. The function
-/// returns an error when the directory structure doesn't match that of a dSYM
-/// bundle.
-static Expected<std::vector<std::string>> getInputs(bool DsymAsInput) {
-  if (!DsymAsInput)
-    return InputFiles;
-
-  // If we are updating, we might get dSYM bundles as input.
-  std::vector<std::string> Inputs;
-  for (const auto &Input : InputFiles) {
-    if (!llvm::sys::fs::is_directory(Input)) {
-      Inputs.push_back(Input);
-      continue;
-    }
-
-    // Make sure that we're dealing with a dSYM bundle.
-    SmallString<256> BundlePath(Input);
-    sys::path::append(BundlePath, "Contents", "Resources", "DWARF");
-    if (!llvm::sys::fs::is_directory(BundlePath))
-      return make_error<StringError>(
-          Input + " is a directory, but doesn't look like a dSYM bundle.",
-          inconvertibleErrorCode());
-
-    // Create a directory iterator to iterate over all the entries in the
-    // bundle.
-    std::error_code EC;
-    llvm::sys::fs::directory_iterator DirIt(BundlePath, EC);
-    llvm::sys::fs::directory_iterator DirEnd;
-    if (EC)
-      return errorCodeToError(EC);
-
-    // Add each entry to the list of inputs.
-    while (DirIt != DirEnd) {
-      Inputs.push_back(DirIt->path());
-      DirIt.increment(EC);
-      if (EC)
-        return errorCodeToError(EC);
-    }
-  }
-  return Inputs;
-}
-
 int main(int argc, char **argv) {
   InitLLVM X(argc, argv);
 
+  // Parse arguments.
+  DsymutilOptTable T;
+  unsigned MAI;
+  unsigned MAC;
+  ArrayRef<const char *> ArgsArr = makeArrayRef(argv + 1, argc - 1);
+  opt::InputArgList Args = T.ParseArgs(ArgsArr, MAI, MAC);
+
   void *P = (void *)(intptr_t)getOutputFileName;
   std::string SDKPath = llvm::sys::fs::getMainExecutable(argv[0], P);
   SDKPath = llvm::sys::path::parent_path(SDKPath);
 
-  HideUnrelatedOptions({&DsymCategory, &ColorCategory});
-  llvm::cl::ParseCommandLineOptions(
-      argc, argv,
+  if (Args.hasArg(OPT_help)) {
+    T.PrintHelp(
+        llvm::outs(),
+        (std::string(argv[0]) + " [options] <input files>").c_str(),
         "manipulate archived DWARF debug symbol files.\n\n"
         "dsymutil links the DWARF debug information found in the object files\n"
         "for the executable <input file> by using debug symbols information\n"
-      "contained in its symbol table.\n");
-
-  if (Help) {
-    PrintHelpMessage();
+        "contained in its symbol table.\n",
+        false);
     return 0;
   }
 
-  if (Version) {
+  if (Args.hasArg(OPT_version)) {
     llvm::cl::PrintVersionMessage();
     return 0;
   }
 
-  auto OptionsOrErr = getOptions();
+  auto OptionsOrErr = getOptions(Args);
   if (!OptionsOrErr) {
     WithColor::error() << toString(OptionsOrErr.takeError());
     return 1;
   }
 
+  auto &Options = *OptionsOrErr;
+
   llvm::InitializeAllTargetInfos();
   llvm::InitializeAllTargetMCs();
   llvm::InitializeAllTargets();
   llvm::InitializeAllAsmPrinters();
 
-  auto InputsOrErr = getInputs(OptionsOrErr->Update);
-  if (!InputsOrErr) {
-    WithColor::error() << toString(InputsOrErr.takeError()) << '\n';
-    return 1;
-  }
-
-  if (!FlatOut && OutputFileOpt == "-") {
-    WithColor::error() << "cannot emit to standard output without --flat\n";
-    return 1;
-  }
-
-  if (InputsOrErr->size() > 1 && FlatOut && !OutputFileOpt.empty()) {
-    WithColor::error() << "cannot use -o with multiple inputs in flat mode\n";
-    return 1;
-  }
-
-  if (InputFiles.size() > 1 && !SymbolMap.empty() &&
-      !llvm::sys::fs::is_directory(SymbolMap)) {
-    WithColor::error() << "when unobfuscating multiple files, --symbol-map "
-                       << "needs to point to a directory.\n";
-    return 1;
-  }
-
-  if (getenv("RC_DEBUG_OPTIONS"))
-    PaperTrailWarnings = true;
-
-  if (PaperTrailWarnings && InputIsYAMLDebugMap)
-    WithColor::warning()
-        << "Paper trail warnings are not supported for YAML input";
-
-  for (const auto &Arch : ArchFlags)
+  for (const auto &Arch : Options.Archs)
     if (Arch != "*" && Arch != "all" &&
         !llvm::object::MachOObjectFile::isValidArch(Arch)) {
       WithColor::error() << "unsupported cpu architecture: '" << Arch << "'\n";
       return 1;
     }
 
-  SymbolMapLoader SymMapLoader(SymbolMap);
+  SymbolMapLoader SymMapLoader(Options.SymbolMap);
 
-  for (auto &InputFile : *InputsOrErr) {
+  for (auto &InputFile : Options.InputFiles) {
     // Dump the symbol table for each input file and requested arch
-    if (DumpStab) {
-      if (!dumpStab(InputFile, ArchFlags, OsoPrependPath))
+    if (Options.DumpStab) {
+      if (!dumpStab(InputFile, Options.Archs, Options.LinkOptions.PrependPath))
         return 1;
       continue;
     }
 
     auto DebugMapPtrsOrErr =
-        parseDebugMap(InputFile, ArchFlags, OsoPrependPath, PaperTrailWarnings,
-                      Verbose, InputIsYAMLDebugMap);
+        parseDebugMap(InputFile, Options.Archs, Options.LinkOptions.PrependPath,
+                      Options.PaperTrailWarnings, Options.LinkOptions.Verbose,
+                      Options.InputIsYAMLDebugMap);
 
     if (auto EC = DebugMapPtrsOrErr.getError()) {
       WithColor::error() << "cannot parse the debug map for '" << InputFile
                          << "': " << EC.message() << '\n';
       return 1;
     }
 
-    if (OptionsOrErr->Update) {
+    if (Options.LinkOptions.Update) {
       // The debug map should be empty. Add one object file corresponding to
       // the input file.
       for (auto &Map : *DebugMapPtrsOrErr)
         Map->addDebugMapObject(InputFile,
                                llvm::sys::TimePoint<std::chrono::seconds>());
     }
 
     // Ensure that the debug map is not empty (anymore).
     if (DebugMapPtrsOrErr->empty()) {
       WithColor::error() << "no architecture to link\n";
       return 1;
     }
 
     // Shared a single binary holder for all the link steps.
     BinaryHolder BinHolder;
 
-    unsigned ThreadCount =
-        std::min<unsigned>(OptionsOrErr->Threads, DebugMapPtrsOrErr->size());
+    unsigned ThreadCount = std::min<unsigned>(Options.LinkOptions.Threads,
+                                              DebugMapPtrsOrErr->size());
     llvm::ThreadPool Threads(ThreadCount);
 
     // If there is more than one link to execute, we need to generate
     // temporary files.
     bool NeedsTempFiles =
-        !DumpDebugMap && (OutputFileOpt != "-") &&
-        (DebugMapPtrsOrErr->size() != 1 || OptionsOrErr->Update);
+        !Options.DumpDebugMap && (Options.OutputFile != "-") &&
+        (DebugMapPtrsOrErr->size() != 1 || Options.LinkOptions.Update);
 
     llvm::SmallVector<MachOUtils::ArchAndFile, 4> TempFiles;
     std::atomic_char AllOK(1);
     for (auto &Map : *DebugMapPtrsOrErr) {
-      if (Verbose || DumpDebugMap)
+      if (Options.LinkOptions.Verbose || Options.DumpDebugMap)
         Map->print(llvm::outs());
 
-      if (DumpDebugMap)
+      if (Options.DumpDebugMap)
         continue;
 
-      if (!SymbolMap.empty())
-        OptionsOrErr->Translator = SymMapLoader.Load(InputFile, *Map);
+      if (!Options.SymbolMap.empty())
+        Options.LinkOptions.Translator = SymMapLoader.Load(InputFile, *Map);
 
       if (Map->begin() == Map->end())
         WithColor::warning()
             << "no debug symbols in executable (-arch "
             << MachOUtils::getArchName(Map->getTriple().getArchName()) << ")\n";
 
       // Using a std::shared_ptr rather than std::unique_ptr because move-only
       // types don't work with std::bind in the ThreadPool implementation.
       std::shared_ptr<raw_fd_ostream> OS;
 
       Expected<OutputLocation> OutputLocationOrErr =
-          getOutputFileName(InputFile);
+          getOutputFileName(InputFile, Options);
       if (!OutputLocationOrErr) {
         WithColor::error() << toString(OutputLocationOrErr.takeError());
         return 1;
       }
-      OptionsOrErr->ResourceDir = OutputLocationOrErr->getResourceDir();
+      Options.LinkOptions.ResourceDir = OutputLocationOrErr->getResourceDir();
 
       std::string OutputFile = OutputLocationOrErr->DWARFFile;
       if (NeedsTempFiles) {
         TempFiles.emplace_back(Map->getTriple().getArchName().str());
 
         auto E = TempFiles.back().createTempFile();
         if (E) {
           WithColor::error() << toString(std::move(E));
           return 1;
         }
 
         auto &TempFile = *(TempFiles.back().File);
         OS = std::make_shared<raw_fd_ostream>(TempFile.FD,
                                               /*shouldClose*/ false);
         OutputFile = TempFile.TmpName;
       } else {
         std::error_code EC;
-        OS = std::make_shared<raw_fd_ostream>(NoOutput ? "-" : OutputFile, EC,
-                                              sys::fs::OF_None);
+        OS = std::make_shared<raw_fd_ostream>(
+            Options.LinkOptions.NoOutput ? "-" : OutputFile, EC,
         if (EC) {
           WithColor::error() << OutputFile << ": " << EC.message();
           return 1;
         }
       }
 
+      const bool Verify = Options.Verify && !Options.LinkOptions.NoOutput;
       auto LinkLambda = [&, OutputFile](std::shared_ptr<raw_fd_ostream> Stream,
                                         LinkOptions Options) {
         AllOK.fetch_and(
             linkDwarf(*Stream, BinHolder, *Map, std::move(Options)));
         Stream->flush();
-        if (Verify && !NoOutput)
-          AllOK.fetch_and(verify(OutputFile, Map->getTriple().getArchName()));
+        if (Verify)
+          AllOK.fetch_and(verify(OutputFile, Map->getTriple().getArchName(),
+                                 Options.Verbose));
       };
 
       // FIXME: The DwarfLinker can have some very deep recursion that can max
       // out the (significantly smaller) stack when using threads. We don't
       // want this limitation when we only have a single thread.
       if (ThreadCount == 1)
-        LinkLambda(OS, *OptionsOrErr);
+        LinkLambda(OS, Options.LinkOptions);
       else
-        Threads.async(LinkLambda, OS, *OptionsOrErr);
+        Threads.async(LinkLambda, OS, Options.LinkOptions);
     }
 
     Threads.wait();
 
     if (!AllOK)
       return 1;
 
     if (NeedsTempFiles) {
-      Expected<OutputLocation> OutputLocationOrErr = getOutputFileName(InputFile);
+      Expected<OutputLocation> OutputLocationOrErr =
+          getOutputFileName(InputFile, Options);
       if (!OutputLocationOrErr) {
         WithColor::error() << toString(OutputLocationOrErr.takeError());
         return 1;
       }
       if (!MachOUtils::generateUniversalBinary(TempFiles,
                                                OutputLocationOrErr->DWARFFile,
-                                               *OptionsOrErr, SDKPath))
+                                               Options.LinkOptions, SDKPath))
         return 1;
     }
   }
 
   return 0;
 }