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      1 //===-- CommandLine.cpp - Command line parser implementation --------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This class implements a command line argument processor that is useful when
     11 // creating a tool.  It provides a simple, minimalistic interface that is easily
     12 // extensible and supports nonlocal (library) command line options.
     13 //
     14 // Note that rather than trying to figure out what this code does, you could try
     15 // reading the library documentation located in docs/CommandLine.html
     16 //
     17 //===----------------------------------------------------------------------===//
     18 
     19 #include "llvm/Support/CommandLine.h"
     20 #include "llvm-c/Support.h"
     21 #include "llvm/ADT/ArrayRef.h"
     22 #include "llvm/ADT/DenseMap.h"
     23 #include "llvm/ADT/Optional.h"
     24 #include "llvm/ADT/STLExtras.h"
     25 #include "llvm/ADT/SmallPtrSet.h"
     26 #include "llvm/ADT/SmallString.h"
     27 #include "llvm/ADT/StringMap.h"
     28 #include "llvm/ADT/Twine.h"
     29 #include "llvm/Config/config.h"
     30 #include "llvm/Support/ConvertUTF.h"
     31 #include "llvm/Support/Debug.h"
     32 #include "llvm/Support/ErrorHandling.h"
     33 #include "llvm/Support/FileSystem.h"
     34 #include "llvm/Support/Host.h"
     35 #include "llvm/Support/ManagedStatic.h"
     36 #include "llvm/Support/MemoryBuffer.h"
     37 #include "llvm/Support/Path.h"
     38 #include "llvm/Support/Process.h"
     39 #include "llvm/Support/StringSaver.h"
     40 #include "llvm/Support/raw_ostream.h"
     41 #include <cstdlib>
     42 #include <map>
     43 using namespace llvm;
     44 using namespace cl;
     45 
     46 #define DEBUG_TYPE "commandline"
     47 
     48 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
     49 namespace llvm {
     50 // If LLVM_ENABLE_ABI_BREAKING_CHECKS is set the flag -mllvm -reverse-iterate
     51 // can be used to toggle forward/reverse iteration of unordered containers.
     52 // This will help uncover differences in codegen caused due to undefined
     53 // iteration order.
     54 static cl::opt<bool, true> ReverseIteration("reverse-iterate",
     55   cl::location(ReverseIterate<bool>::value));
     56 }
     57 #endif
     58 
     59 //===----------------------------------------------------------------------===//
     60 // Template instantiations and anchors.
     61 //
     62 namespace llvm {
     63 namespace cl {
     64 template class basic_parser<bool>;
     65 template class basic_parser<boolOrDefault>;
     66 template class basic_parser<int>;
     67 template class basic_parser<unsigned>;
     68 template class basic_parser<unsigned long long>;
     69 template class basic_parser<double>;
     70 template class basic_parser<float>;
     71 template class basic_parser<std::string>;
     72 template class basic_parser<char>;
     73 
     74 template class opt<unsigned>;
     75 template class opt<int>;
     76 template class opt<std::string>;
     77 template class opt<char>;
     78 template class opt<bool>;
     79 }
     80 } // end namespace llvm::cl
     81 
     82 // Pin the vtables to this file.
     83 void GenericOptionValue::anchor() {}
     84 void OptionValue<boolOrDefault>::anchor() {}
     85 void OptionValue<std::string>::anchor() {}
     86 void Option::anchor() {}
     87 void basic_parser_impl::anchor() {}
     88 void parser<bool>::anchor() {}
     89 void parser<boolOrDefault>::anchor() {}
     90 void parser<int>::anchor() {}
     91 void parser<unsigned>::anchor() {}
     92 void parser<unsigned long long>::anchor() {}
     93 void parser<double>::anchor() {}
     94 void parser<float>::anchor() {}
     95 void parser<std::string>::anchor() {}
     96 void parser<char>::anchor() {}
     97 
     98 //===----------------------------------------------------------------------===//
     99 
    100 namespace {
    101 
    102 class CommandLineParser {
    103 public:
    104   // Globals for name and overview of program.  Program name is not a string to
    105   // avoid static ctor/dtor issues.
    106   std::string ProgramName;
    107   StringRef ProgramOverview;
    108 
    109   // This collects additional help to be printed.
    110   std::vector<StringRef> MoreHelp;
    111 
    112   // This collects the different option categories that have been registered.
    113   SmallPtrSet<OptionCategory *, 16> RegisteredOptionCategories;
    114 
    115   // This collects the different subcommands that have been registered.
    116   SmallPtrSet<SubCommand *, 4> RegisteredSubCommands;
    117 
    118   CommandLineParser() : ActiveSubCommand(nullptr) {
    119     registerSubCommand(&*TopLevelSubCommand);
    120     registerSubCommand(&*AllSubCommands);
    121   }
    122 
    123   void ResetAllOptionOccurrences();
    124 
    125   bool ParseCommandLineOptions(int argc, const char *const *argv,
    126                                StringRef Overview, bool IgnoreErrors);
    127 
    128   void addLiteralOption(Option &Opt, SubCommand *SC, StringRef Name) {
    129     if (Opt.hasArgStr())
    130       return;
    131     if (!SC->OptionsMap.insert(std::make_pair(Name, &Opt)).second) {
    132       errs() << ProgramName << ": CommandLine Error: Option '" << Name
    133              << "' registered more than once!\n";
    134       report_fatal_error("inconsistency in registered CommandLine options");
    135     }
    136 
    137     // If we're adding this to all sub-commands, add it to the ones that have
    138     // already been registered.
    139     if (SC == &*AllSubCommands) {
    140       for (const auto &Sub : RegisteredSubCommands) {
    141         if (SC == Sub)
    142           continue;
    143         addLiteralOption(Opt, Sub, Name);
    144       }
    145     }
    146   }
    147 
    148   void addLiteralOption(Option &Opt, StringRef Name) {
    149     if (Opt.Subs.empty())
    150       addLiteralOption(Opt, &*TopLevelSubCommand, Name);
    151     else {
    152       for (auto SC : Opt.Subs)
    153         addLiteralOption(Opt, SC, Name);
    154     }
    155   }
    156 
    157   void addOption(Option *O, SubCommand *SC) {
    158     bool HadErrors = false;
    159     if (O->hasArgStr()) {
    160       // Add argument to the argument map!
    161       if (!SC->OptionsMap.insert(std::make_pair(O->ArgStr, O)).second) {
    162         errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
    163                << "' registered more than once!\n";
    164         HadErrors = true;
    165       }
    166     }
    167 
    168     // Remember information about positional options.
    169     if (O->getFormattingFlag() == cl::Positional)
    170       SC->PositionalOpts.push_back(O);
    171     else if (O->getMiscFlags() & cl::Sink) // Remember sink options
    172       SC->SinkOpts.push_back(O);
    173     else if (O->getNumOccurrencesFlag() == cl::ConsumeAfter) {
    174       if (SC->ConsumeAfterOpt) {
    175         O->error("Cannot specify more than one option with cl::ConsumeAfter!");
    176         HadErrors = true;
    177       }
    178       SC->ConsumeAfterOpt = O;
    179     }
    180 
    181     // Fail hard if there were errors. These are strictly unrecoverable and
    182     // indicate serious issues such as conflicting option names or an
    183     // incorrectly
    184     // linked LLVM distribution.
    185     if (HadErrors)
    186       report_fatal_error("inconsistency in registered CommandLine options");
    187 
    188     // If we're adding this to all sub-commands, add it to the ones that have
    189     // already been registered.
    190     if (SC == &*AllSubCommands) {
    191       for (const auto &Sub : RegisteredSubCommands) {
    192         if (SC == Sub)
    193           continue;
    194         addOption(O, Sub);
    195       }
    196     }
    197   }
    198 
    199   void addOption(Option *O) {
    200     if (O->Subs.empty()) {
    201       addOption(O, &*TopLevelSubCommand);
    202     } else {
    203       for (auto SC : O->Subs)
    204         addOption(O, SC);
    205     }
    206   }
    207 
    208   void removeOption(Option *O, SubCommand *SC) {
    209     SmallVector<StringRef, 16> OptionNames;
    210     O->getExtraOptionNames(OptionNames);
    211     if (O->hasArgStr())
    212       OptionNames.push_back(O->ArgStr);
    213 
    214     SubCommand &Sub = *SC;
    215     for (auto Name : OptionNames)
    216       Sub.OptionsMap.erase(Name);
    217 
    218     if (O->getFormattingFlag() == cl::Positional)
    219       for (auto Opt = Sub.PositionalOpts.begin();
    220            Opt != Sub.PositionalOpts.end(); ++Opt) {
    221         if (*Opt == O) {
    222           Sub.PositionalOpts.erase(Opt);
    223           break;
    224         }
    225       }
    226     else if (O->getMiscFlags() & cl::Sink)
    227       for (auto Opt = Sub.SinkOpts.begin(); Opt != Sub.SinkOpts.end(); ++Opt) {
    228         if (*Opt == O) {
    229           Sub.SinkOpts.erase(Opt);
    230           break;
    231         }
    232       }
    233     else if (O == Sub.ConsumeAfterOpt)
    234       Sub.ConsumeAfterOpt = nullptr;
    235   }
    236 
    237   void removeOption(Option *O) {
    238     if (O->Subs.empty())
    239       removeOption(O, &*TopLevelSubCommand);
    240     else {
    241       if (O->isInAllSubCommands()) {
    242         for (auto SC : RegisteredSubCommands)
    243           removeOption(O, SC);
    244       } else {
    245         for (auto SC : O->Subs)
    246           removeOption(O, SC);
    247       }
    248     }
    249   }
    250 
    251   bool hasOptions(const SubCommand &Sub) const {
    252     return (!Sub.OptionsMap.empty() || !Sub.PositionalOpts.empty() ||
    253             nullptr != Sub.ConsumeAfterOpt);
    254   }
    255 
    256   bool hasOptions() const {
    257     for (const auto &S : RegisteredSubCommands) {
    258       if (hasOptions(*S))
    259         return true;
    260     }
    261     return false;
    262   }
    263 
    264   SubCommand *getActiveSubCommand() { return ActiveSubCommand; }
    265 
    266   void updateArgStr(Option *O, StringRef NewName, SubCommand *SC) {
    267     SubCommand &Sub = *SC;
    268     if (!Sub.OptionsMap.insert(std::make_pair(NewName, O)).second) {
    269       errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
    270              << "' registered more than once!\n";
    271       report_fatal_error("inconsistency in registered CommandLine options");
    272     }
    273     Sub.OptionsMap.erase(O->ArgStr);
    274   }
    275 
    276   void updateArgStr(Option *O, StringRef NewName) {
    277     if (O->Subs.empty())
    278       updateArgStr(O, NewName, &*TopLevelSubCommand);
    279     else {
    280       for (auto SC : O->Subs)
    281         updateArgStr(O, NewName, SC);
    282     }
    283   }
    284 
    285   void printOptionValues();
    286 
    287   void registerCategory(OptionCategory *cat) {
    288     assert(count_if(RegisteredOptionCategories,
    289                     [cat](const OptionCategory *Category) {
    290              return cat->getName() == Category->getName();
    291            }) == 0 &&
    292            "Duplicate option categories");
    293 
    294     RegisteredOptionCategories.insert(cat);
    295   }
    296 
    297   void registerSubCommand(SubCommand *sub) {
    298     assert(count_if(RegisteredSubCommands,
    299                     [sub](const SubCommand *Sub) {
    300                       return (!sub->getName().empty()) &&
    301                              (Sub->getName() == sub->getName());
    302                     }) == 0 &&
    303            "Duplicate subcommands");
    304     RegisteredSubCommands.insert(sub);
    305 
    306     // For all options that have been registered for all subcommands, add the
    307     // option to this subcommand now.
    308     if (sub != &*AllSubCommands) {
    309       for (auto &E : AllSubCommands->OptionsMap) {
    310         Option *O = E.second;
    311         if ((O->isPositional() || O->isSink() || O->isConsumeAfter()) ||
    312             O->hasArgStr())
    313           addOption(O, sub);
    314         else
    315           addLiteralOption(*O, sub, E.first());
    316       }
    317     }
    318   }
    319 
    320   void unregisterSubCommand(SubCommand *sub) {
    321     RegisteredSubCommands.erase(sub);
    322   }
    323 
    324   iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
    325   getRegisteredSubcommands() {
    326     return make_range(RegisteredSubCommands.begin(),
    327                       RegisteredSubCommands.end());
    328   }
    329 
    330   void reset() {
    331     ActiveSubCommand = nullptr;
    332     ProgramName.clear();
    333     ProgramOverview = StringRef();
    334 
    335     MoreHelp.clear();
    336     RegisteredOptionCategories.clear();
    337 
    338     ResetAllOptionOccurrences();
    339     RegisteredSubCommands.clear();
    340 
    341     TopLevelSubCommand->reset();
    342     AllSubCommands->reset();
    343     registerSubCommand(&*TopLevelSubCommand);
    344     registerSubCommand(&*AllSubCommands);
    345   }
    346 
    347 private:
    348   SubCommand *ActiveSubCommand;
    349 
    350   Option *LookupOption(SubCommand &Sub, StringRef &Arg, StringRef &Value);
    351   SubCommand *LookupSubCommand(StringRef Name);
    352 };
    353 
    354 } // namespace
    355 
    356 static ManagedStatic<CommandLineParser> GlobalParser;
    357 
    358 void cl::AddLiteralOption(Option &O, StringRef Name) {
    359   GlobalParser->addLiteralOption(O, Name);
    360 }
    361 
    362 extrahelp::extrahelp(StringRef Help) : morehelp(Help) {
    363   GlobalParser->MoreHelp.push_back(Help);
    364 }
    365 
    366 void Option::addArgument() {
    367   GlobalParser->addOption(this);
    368   FullyInitialized = true;
    369 }
    370 
    371 void Option::removeArgument() { GlobalParser->removeOption(this); }
    372 
    373 void Option::setArgStr(StringRef S) {
    374   if (FullyInitialized)
    375     GlobalParser->updateArgStr(this, S);
    376   ArgStr = S;
    377 }
    378 
    379 // Initialise the general option category.
    380 OptionCategory llvm::cl::GeneralCategory("General options");
    381 
    382 void OptionCategory::registerCategory() {
    383   GlobalParser->registerCategory(this);
    384 }
    385 
    386 // A special subcommand representing no subcommand
    387 ManagedStatic<SubCommand> llvm::cl::TopLevelSubCommand;
    388 
    389 // A special subcommand that can be used to put an option into all subcommands.
    390 ManagedStatic<SubCommand> llvm::cl::AllSubCommands;
    391 
    392 void SubCommand::registerSubCommand() {
    393   GlobalParser->registerSubCommand(this);
    394 }
    395 
    396 void SubCommand::unregisterSubCommand() {
    397   GlobalParser->unregisterSubCommand(this);
    398 }
    399 
    400 void SubCommand::reset() {
    401   PositionalOpts.clear();
    402   SinkOpts.clear();
    403   OptionsMap.clear();
    404 
    405   ConsumeAfterOpt = nullptr;
    406 }
    407 
    408 SubCommand::operator bool() const {
    409   return (GlobalParser->getActiveSubCommand() == this);
    410 }
    411 
    412 //===----------------------------------------------------------------------===//
    413 // Basic, shared command line option processing machinery.
    414 //
    415 
    416 /// LookupOption - Lookup the option specified by the specified option on the
    417 /// command line.  If there is a value specified (after an equal sign) return
    418 /// that as well.  This assumes that leading dashes have already been stripped.
    419 Option *CommandLineParser::LookupOption(SubCommand &Sub, StringRef &Arg,
    420                                         StringRef &Value) {
    421   // Reject all dashes.
    422   if (Arg.empty())
    423     return nullptr;
    424   assert(&Sub != &*AllSubCommands);
    425 
    426   size_t EqualPos = Arg.find('=');
    427 
    428   // If we have an equals sign, remember the value.
    429   if (EqualPos == StringRef::npos) {
    430     // Look up the option.
    431     auto I = Sub.OptionsMap.find(Arg);
    432     if (I == Sub.OptionsMap.end())
    433       return nullptr;
    434 
    435     return I != Sub.OptionsMap.end() ? I->second : nullptr;
    436   }
    437 
    438   // If the argument before the = is a valid option name, we match.  If not,
    439   // return Arg unmolested.
    440   auto I = Sub.OptionsMap.find(Arg.substr(0, EqualPos));
    441   if (I == Sub.OptionsMap.end())
    442     return nullptr;
    443 
    444   Value = Arg.substr(EqualPos + 1);
    445   Arg = Arg.substr(0, EqualPos);
    446   return I->second;
    447 }
    448 
    449 SubCommand *CommandLineParser::LookupSubCommand(StringRef Name) {
    450   if (Name.empty())
    451     return &*TopLevelSubCommand;
    452   for (auto S : RegisteredSubCommands) {
    453     if (S == &*AllSubCommands)
    454       continue;
    455     if (S->getName().empty())
    456       continue;
    457 
    458     if (StringRef(S->getName()) == StringRef(Name))
    459       return S;
    460   }
    461   return &*TopLevelSubCommand;
    462 }
    463 
    464 /// LookupNearestOption - Lookup the closest match to the option specified by
    465 /// the specified option on the command line.  If there is a value specified
    466 /// (after an equal sign) return that as well.  This assumes that leading dashes
    467 /// have already been stripped.
    468 static Option *LookupNearestOption(StringRef Arg,
    469                                    const StringMap<Option *> &OptionsMap,
    470                                    std::string &NearestString) {
    471   // Reject all dashes.
    472   if (Arg.empty())
    473     return nullptr;
    474 
    475   // Split on any equal sign.
    476   std::pair<StringRef, StringRef> SplitArg = Arg.split('=');
    477   StringRef &LHS = SplitArg.first; // LHS == Arg when no '=' is present.
    478   StringRef &RHS = SplitArg.second;
    479 
    480   // Find the closest match.
    481   Option *Best = nullptr;
    482   unsigned BestDistance = 0;
    483   for (StringMap<Option *>::const_iterator it = OptionsMap.begin(),
    484                                            ie = OptionsMap.end();
    485        it != ie; ++it) {
    486     Option *O = it->second;
    487     SmallVector<StringRef, 16> OptionNames;
    488     O->getExtraOptionNames(OptionNames);
    489     if (O->hasArgStr())
    490       OptionNames.push_back(O->ArgStr);
    491 
    492     bool PermitValue = O->getValueExpectedFlag() != cl::ValueDisallowed;
    493     StringRef Flag = PermitValue ? LHS : Arg;
    494     for (auto Name : OptionNames) {
    495       unsigned Distance = StringRef(Name).edit_distance(
    496           Flag, /*AllowReplacements=*/true, /*MaxEditDistance=*/BestDistance);
    497       if (!Best || Distance < BestDistance) {
    498         Best = O;
    499         BestDistance = Distance;
    500         if (RHS.empty() || !PermitValue)
    501           NearestString = Name;
    502         else
    503           NearestString = (Twine(Name) + "=" + RHS).str();
    504       }
    505     }
    506   }
    507 
    508   return Best;
    509 }
    510 
    511 /// CommaSeparateAndAddOccurrence - A wrapper around Handler->addOccurrence()
    512 /// that does special handling of cl::CommaSeparated options.
    513 static bool CommaSeparateAndAddOccurrence(Option *Handler, unsigned pos,
    514                                           StringRef ArgName, StringRef Value,
    515                                           bool MultiArg = false) {
    516   // Check to see if this option accepts a comma separated list of values.  If
    517   // it does, we have to split up the value into multiple values.
    518   if (Handler->getMiscFlags() & CommaSeparated) {
    519     StringRef Val(Value);
    520     StringRef::size_type Pos = Val.find(',');
    521 
    522     while (Pos != StringRef::npos) {
    523       // Process the portion before the comma.
    524       if (Handler->addOccurrence(pos, ArgName, Val.substr(0, Pos), MultiArg))
    525         return true;
    526       // Erase the portion before the comma, AND the comma.
    527       Val = Val.substr(Pos + 1);
    528       // Check for another comma.
    529       Pos = Val.find(',');
    530     }
    531 
    532     Value = Val;
    533   }
    534 
    535   return Handler->addOccurrence(pos, ArgName, Value, MultiArg);
    536 }
    537 
    538 /// ProvideOption - For Value, this differentiates between an empty value ("")
    539 /// and a null value (StringRef()).  The later is accepted for arguments that
    540 /// don't allow a value (-foo) the former is rejected (-foo=).
    541 static inline bool ProvideOption(Option *Handler, StringRef ArgName,
    542                                  StringRef Value, int argc,
    543                                  const char *const *argv, int &i) {
    544   // Is this a multi-argument option?
    545   unsigned NumAdditionalVals = Handler->getNumAdditionalVals();
    546 
    547   // Enforce value requirements
    548   switch (Handler->getValueExpectedFlag()) {
    549   case ValueRequired:
    550     if (!Value.data()) { // No value specified?
    551       if (i + 1 >= argc)
    552         return Handler->error("requires a value!");
    553       // Steal the next argument, like for '-o filename'
    554       assert(argv && "null check");
    555       Value = StringRef(argv[++i]);
    556     }
    557     break;
    558   case ValueDisallowed:
    559     if (NumAdditionalVals > 0)
    560       return Handler->error("multi-valued option specified"
    561                             " with ValueDisallowed modifier!");
    562 
    563     if (Value.data())
    564       return Handler->error("does not allow a value! '" + Twine(Value) +
    565                             "' specified.");
    566     break;
    567   case ValueOptional:
    568     break;
    569   }
    570 
    571   // If this isn't a multi-arg option, just run the handler.
    572   if (NumAdditionalVals == 0)
    573     return CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value);
    574 
    575   // If it is, run the handle several times.
    576   bool MultiArg = false;
    577 
    578   if (Value.data()) {
    579     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
    580       return true;
    581     --NumAdditionalVals;
    582     MultiArg = true;
    583   }
    584 
    585   while (NumAdditionalVals > 0) {
    586     if (i + 1 >= argc)
    587       return Handler->error("not enough values!");
    588     assert(argv && "null check");
    589     Value = StringRef(argv[++i]);
    590 
    591     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
    592       return true;
    593     MultiArg = true;
    594     --NumAdditionalVals;
    595   }
    596   return false;
    597 }
    598 
    599 static bool ProvidePositionalOption(Option *Handler, StringRef Arg, int i) {
    600   int Dummy = i;
    601   return ProvideOption(Handler, Handler->ArgStr, Arg, 0, nullptr, Dummy);
    602 }
    603 
    604 // Option predicates...
    605 static inline bool isGrouping(const Option *O) {
    606   return O->getFormattingFlag() == cl::Grouping;
    607 }
    608 static inline bool isPrefixedOrGrouping(const Option *O) {
    609   return isGrouping(O) || O->getFormattingFlag() == cl::Prefix;
    610 }
    611 
    612 // getOptionPred - Check to see if there are any options that satisfy the
    613 // specified predicate with names that are the prefixes in Name.  This is
    614 // checked by progressively stripping characters off of the name, checking to
    615 // see if there options that satisfy the predicate.  If we find one, return it,
    616 // otherwise return null.
    617 //
    618 static Option *getOptionPred(StringRef Name, size_t &Length,
    619                              bool (*Pred)(const Option *),
    620                              const StringMap<Option *> &OptionsMap) {
    621 
    622   StringMap<Option *>::const_iterator OMI = OptionsMap.find(Name);
    623 
    624   // Loop while we haven't found an option and Name still has at least two
    625   // characters in it (so that the next iteration will not be the empty
    626   // string.
    627   while (OMI == OptionsMap.end() && Name.size() > 1) {
    628     Name = Name.substr(0, Name.size() - 1); // Chop off the last character.
    629     OMI = OptionsMap.find(Name);
    630   }
    631 
    632   if (OMI != OptionsMap.end() && Pred(OMI->second)) {
    633     Length = Name.size();
    634     return OMI->second; // Found one!
    635   }
    636   return nullptr; // No option found!
    637 }
    638 
    639 /// HandlePrefixedOrGroupedOption - The specified argument string (which started
    640 /// with at least one '-') does not fully match an available option.  Check to
    641 /// see if this is a prefix or grouped option.  If so, split arg into output an
    642 /// Arg/Value pair and return the Option to parse it with.
    643 static Option *
    644 HandlePrefixedOrGroupedOption(StringRef &Arg, StringRef &Value,
    645                               bool &ErrorParsing,
    646                               const StringMap<Option *> &OptionsMap) {
    647   if (Arg.size() == 1)
    648     return nullptr;
    649 
    650   // Do the lookup!
    651   size_t Length = 0;
    652   Option *PGOpt = getOptionPred(Arg, Length, isPrefixedOrGrouping, OptionsMap);
    653   if (!PGOpt)
    654     return nullptr;
    655 
    656   // If the option is a prefixed option, then the value is simply the
    657   // rest of the name...  so fall through to later processing, by
    658   // setting up the argument name flags and value fields.
    659   if (PGOpt->getFormattingFlag() == cl::Prefix) {
    660     Value = Arg.substr(Length);
    661     Arg = Arg.substr(0, Length);
    662     assert(OptionsMap.count(Arg) && OptionsMap.find(Arg)->second == PGOpt);
    663     return PGOpt;
    664   }
    665 
    666   // This must be a grouped option... handle them now.  Grouping options can't
    667   // have values.
    668   assert(isGrouping(PGOpt) && "Broken getOptionPred!");
    669 
    670   do {
    671     // Move current arg name out of Arg into OneArgName.
    672     StringRef OneArgName = Arg.substr(0, Length);
    673     Arg = Arg.substr(Length);
    674 
    675     // Because ValueRequired is an invalid flag for grouped arguments,
    676     // we don't need to pass argc/argv in.
    677     assert(PGOpt->getValueExpectedFlag() != cl::ValueRequired &&
    678            "Option can not be cl::Grouping AND cl::ValueRequired!");
    679     int Dummy = 0;
    680     ErrorParsing |=
    681         ProvideOption(PGOpt, OneArgName, StringRef(), 0, nullptr, Dummy);
    682 
    683     // Get the next grouping option.
    684     PGOpt = getOptionPred(Arg, Length, isGrouping, OptionsMap);
    685   } while (PGOpt && Length != Arg.size());
    686 
    687   // Return the last option with Arg cut down to just the last one.
    688   return PGOpt;
    689 }
    690 
    691 static bool RequiresValue(const Option *O) {
    692   return O->getNumOccurrencesFlag() == cl::Required ||
    693          O->getNumOccurrencesFlag() == cl::OneOrMore;
    694 }
    695 
    696 static bool EatsUnboundedNumberOfValues(const Option *O) {
    697   return O->getNumOccurrencesFlag() == cl::ZeroOrMore ||
    698          O->getNumOccurrencesFlag() == cl::OneOrMore;
    699 }
    700 
    701 static bool isWhitespace(char C) { return strchr(" \t\n\r\f\v", C); }
    702 
    703 static bool isQuote(char C) { return C == '\"' || C == '\''; }
    704 
    705 void cl::TokenizeGNUCommandLine(StringRef Src, StringSaver &Saver,
    706                                 SmallVectorImpl<const char *> &NewArgv,
    707                                 bool MarkEOLs) {
    708   SmallString<128> Token;
    709   for (size_t I = 0, E = Src.size(); I != E; ++I) {
    710     // Consume runs of whitespace.
    711     if (Token.empty()) {
    712       while (I != E && isWhitespace(Src[I])) {
    713         // Mark the end of lines in response files
    714         if (MarkEOLs && Src[I] == '\n')
    715           NewArgv.push_back(nullptr);
    716         ++I;
    717       }
    718       if (I == E)
    719         break;
    720     }
    721 
    722     // Backslash escapes the next character.
    723     if (I + 1 < E && Src[I] == '\\') {
    724       ++I; // Skip the escape.
    725       Token.push_back(Src[I]);
    726       continue;
    727     }
    728 
    729     // Consume a quoted string.
    730     if (isQuote(Src[I])) {
    731       char Quote = Src[I++];
    732       while (I != E && Src[I] != Quote) {
    733         // Backslash escapes the next character.
    734         if (Src[I] == '\\' && I + 1 != E)
    735           ++I;
    736         Token.push_back(Src[I]);
    737         ++I;
    738       }
    739       if (I == E)
    740         break;
    741       continue;
    742     }
    743 
    744     // End the token if this is whitespace.
    745     if (isWhitespace(Src[I])) {
    746       if (!Token.empty())
    747         NewArgv.push_back(Saver.save(StringRef(Token)).data());
    748       Token.clear();
    749       continue;
    750     }
    751 
    752     // This is a normal character.  Append it.
    753     Token.push_back(Src[I]);
    754   }
    755 
    756   // Append the last token after hitting EOF with no whitespace.
    757   if (!Token.empty())
    758     NewArgv.push_back(Saver.save(StringRef(Token)).data());
    759   // Mark the end of response files
    760   if (MarkEOLs)
    761     NewArgv.push_back(nullptr);
    762 }
    763 
    764 /// Backslashes are interpreted in a rather complicated way in the Windows-style
    765 /// command line, because backslashes are used both to separate path and to
    766 /// escape double quote. This method consumes runs of backslashes as well as the
    767 /// following double quote if it's escaped.
    768 ///
    769 ///  * If an even number of backslashes is followed by a double quote, one
    770 ///    backslash is output for every pair of backslashes, and the last double
    771 ///    quote remains unconsumed. The double quote will later be interpreted as
    772 ///    the start or end of a quoted string in the main loop outside of this
    773 ///    function.
    774 ///
    775 ///  * If an odd number of backslashes is followed by a double quote, one
    776 ///    backslash is output for every pair of backslashes, and a double quote is
    777 ///    output for the last pair of backslash-double quote. The double quote is
    778 ///    consumed in this case.
    779 ///
    780 ///  * Otherwise, backslashes are interpreted literally.
    781 static size_t parseBackslash(StringRef Src, size_t I, SmallString<128> &Token) {
    782   size_t E = Src.size();
    783   int BackslashCount = 0;
    784   // Skip the backslashes.
    785   do {
    786     ++I;
    787     ++BackslashCount;
    788   } while (I != E && Src[I] == '\\');
    789 
    790   bool FollowedByDoubleQuote = (I != E && Src[I] == '"');
    791   if (FollowedByDoubleQuote) {
    792     Token.append(BackslashCount / 2, '\\');
    793     if (BackslashCount % 2 == 0)
    794       return I - 1;
    795     Token.push_back('"');
    796     return I;
    797   }
    798   Token.append(BackslashCount, '\\');
    799   return I - 1;
    800 }
    801 
    802 void cl::TokenizeWindowsCommandLine(StringRef Src, StringSaver &Saver,
    803                                     SmallVectorImpl<const char *> &NewArgv,
    804                                     bool MarkEOLs) {
    805   SmallString<128> Token;
    806 
    807   // This is a small state machine to consume characters until it reaches the
    808   // end of the source string.
    809   enum { INIT, UNQUOTED, QUOTED } State = INIT;
    810   for (size_t I = 0, E = Src.size(); I != E; ++I) {
    811     // INIT state indicates that the current input index is at the start of
    812     // the string or between tokens.
    813     if (State == INIT) {
    814       if (isWhitespace(Src[I])) {
    815         // Mark the end of lines in response files
    816         if (MarkEOLs && Src[I] == '\n')
    817           NewArgv.push_back(nullptr);
    818         continue;
    819       }
    820       if (Src[I] == '"') {
    821         State = QUOTED;
    822         continue;
    823       }
    824       if (Src[I] == '\\') {
    825         I = parseBackslash(Src, I, Token);
    826         State = UNQUOTED;
    827         continue;
    828       }
    829       Token.push_back(Src[I]);
    830       State = UNQUOTED;
    831       continue;
    832     }
    833 
    834     // UNQUOTED state means that it's reading a token not quoted by double
    835     // quotes.
    836     if (State == UNQUOTED) {
    837       // Whitespace means the end of the token.
    838       if (isWhitespace(Src[I])) {
    839         NewArgv.push_back(Saver.save(StringRef(Token)).data());
    840         Token.clear();
    841         State = INIT;
    842         // Mark the end of lines in response files
    843         if (MarkEOLs && Src[I] == '\n')
    844           NewArgv.push_back(nullptr);
    845         continue;
    846       }
    847       if (Src[I] == '"') {
    848         State = QUOTED;
    849         continue;
    850       }
    851       if (Src[I] == '\\') {
    852         I = parseBackslash(Src, I, Token);
    853         continue;
    854       }
    855       Token.push_back(Src[I]);
    856       continue;
    857     }
    858 
    859     // QUOTED state means that it's reading a token quoted by double quotes.
    860     if (State == QUOTED) {
    861       if (Src[I] == '"') {
    862         State = UNQUOTED;
    863         continue;
    864       }
    865       if (Src[I] == '\\') {
    866         I = parseBackslash(Src, I, Token);
    867         continue;
    868       }
    869       Token.push_back(Src[I]);
    870     }
    871   }
    872   // Append the last token after hitting EOF with no whitespace.
    873   if (!Token.empty())
    874     NewArgv.push_back(Saver.save(StringRef(Token)).data());
    875   // Mark the end of response files
    876   if (MarkEOLs)
    877     NewArgv.push_back(nullptr);
    878 }
    879 
    880 // It is called byte order marker but the UTF-8 BOM is actually not affected
    881 // by the host system's endianness.
    882 static bool hasUTF8ByteOrderMark(ArrayRef<char> S) {
    883   return (S.size() >= 3 && S[0] == '\xef' && S[1] == '\xbb' && S[2] == '\xbf');
    884 }
    885 
    886 static bool ExpandResponseFile(StringRef FName, StringSaver &Saver,
    887                                TokenizerCallback Tokenizer,
    888                                SmallVectorImpl<const char *> &NewArgv,
    889                                bool MarkEOLs, bool RelativeNames) {
    890   ErrorOr<std::unique_ptr<MemoryBuffer>> MemBufOrErr =
    891       MemoryBuffer::getFile(FName);
    892   if (!MemBufOrErr)
    893     return false;
    894   MemoryBuffer &MemBuf = *MemBufOrErr.get();
    895   StringRef Str(MemBuf.getBufferStart(), MemBuf.getBufferSize());
    896 
    897   // If we have a UTF-16 byte order mark, convert to UTF-8 for parsing.
    898   ArrayRef<char> BufRef(MemBuf.getBufferStart(), MemBuf.getBufferEnd());
    899   std::string UTF8Buf;
    900   if (hasUTF16ByteOrderMark(BufRef)) {
    901     if (!convertUTF16ToUTF8String(BufRef, UTF8Buf))
    902       return false;
    903     Str = StringRef(UTF8Buf);
    904   }
    905   // If we see UTF-8 BOM sequence at the beginning of a file, we shall remove
    906   // these bytes before parsing.
    907   // Reference: http://en.wikipedia.org/wiki/UTF-8#Byte_order_mark
    908   else if (hasUTF8ByteOrderMark(BufRef))
    909     Str = StringRef(BufRef.data() + 3, BufRef.size() - 3);
    910 
    911   // Tokenize the contents into NewArgv.
    912   Tokenizer(Str, Saver, NewArgv, MarkEOLs);
    913 
    914   // If names of nested response files should be resolved relative to including
    915   // file, replace the included response file names with their full paths
    916   // obtained by required resolution.
    917   if (RelativeNames)
    918     for (unsigned I = 0; I < NewArgv.size(); ++I)
    919       if (NewArgv[I]) {
    920         StringRef Arg = NewArgv[I];
    921         if (Arg.front() == '@') {
    922           StringRef FileName = Arg.drop_front();
    923           if (llvm::sys::path::is_relative(FileName)) {
    924             SmallString<128> ResponseFile;
    925             ResponseFile.append(1, '@');
    926             if (llvm::sys::path::is_relative(FName)) {
    927               SmallString<128> curr_dir;
    928               llvm::sys::fs::current_path(curr_dir);
    929               ResponseFile.append(curr_dir.str());
    930             }
    931             llvm::sys::path::append(
    932                 ResponseFile, llvm::sys::path::parent_path(FName), FileName);
    933             NewArgv[I] = Saver.save(ResponseFile.c_str()).data();
    934           }
    935         }
    936       }
    937 
    938   return true;
    939 }
    940 
    941 /// \brief Expand response files on a command line recursively using the given
    942 /// StringSaver and tokenization strategy.
    943 bool cl::ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
    944                              SmallVectorImpl<const char *> &Argv,
    945                              bool MarkEOLs, bool RelativeNames) {
    946   unsigned RspFiles = 0;
    947   bool AllExpanded = true;
    948 
    949   // Don't cache Argv.size() because it can change.
    950   for (unsigned I = 0; I != Argv.size();) {
    951     const char *Arg = Argv[I];
    952     // Check if it is an EOL marker
    953     if (Arg == nullptr) {
    954       ++I;
    955       continue;
    956     }
    957     if (Arg[0] != '@') {
    958       ++I;
    959       continue;
    960     }
    961 
    962     // If we have too many response files, leave some unexpanded.  This avoids
    963     // crashing on self-referential response files.
    964     if (RspFiles++ > 20)
    965       return false;
    966 
    967     // Replace this response file argument with the tokenization of its
    968     // contents.  Nested response files are expanded in subsequent iterations.
    969     SmallVector<const char *, 0> ExpandedArgv;
    970     if (!ExpandResponseFile(Arg + 1, Saver, Tokenizer, ExpandedArgv,
    971                             MarkEOLs, RelativeNames)) {
    972       // We couldn't read this file, so we leave it in the argument stream and
    973       // move on.
    974       AllExpanded = false;
    975       ++I;
    976       continue;
    977     }
    978     Argv.erase(Argv.begin() + I);
    979     Argv.insert(Argv.begin() + I, ExpandedArgv.begin(), ExpandedArgv.end());
    980   }
    981   return AllExpanded;
    982 }
    983 
    984 /// ParseEnvironmentOptions - An alternative entry point to the
    985 /// CommandLine library, which allows you to read the program's name
    986 /// from the caller (as PROGNAME) and its command-line arguments from
    987 /// an environment variable (whose name is given in ENVVAR).
    988 ///
    989 void cl::ParseEnvironmentOptions(const char *progName, const char *envVar,
    990                                  const char *Overview) {
    991   // Check args.
    992   assert(progName && "Program name not specified");
    993   assert(envVar && "Environment variable name missing");
    994 
    995   // Get the environment variable they want us to parse options out of.
    996   llvm::Optional<std::string> envValue = sys::Process::GetEnv(StringRef(envVar));
    997   if (!envValue)
    998     return;
    999 
   1000   // Get program's "name", which we wouldn't know without the caller
   1001   // telling us.
   1002   SmallVector<const char *, 20> newArgv;
   1003   BumpPtrAllocator A;
   1004   StringSaver Saver(A);
   1005   newArgv.push_back(Saver.save(progName).data());
   1006 
   1007   // Parse the value of the environment variable into a "command line"
   1008   // and hand it off to ParseCommandLineOptions().
   1009   TokenizeGNUCommandLine(*envValue, Saver, newArgv);
   1010   int newArgc = static_cast<int>(newArgv.size());
   1011   ParseCommandLineOptions(newArgc, &newArgv[0], StringRef(Overview));
   1012 }
   1013 
   1014 bool cl::ParseCommandLineOptions(int argc, const char *const *argv,
   1015                                  StringRef Overview, bool IgnoreErrors) {
   1016   return GlobalParser->ParseCommandLineOptions(argc, argv, Overview,
   1017                                                IgnoreErrors);
   1018 }
   1019 
   1020 void CommandLineParser::ResetAllOptionOccurrences() {
   1021   // So that we can parse different command lines multiple times in succession
   1022   // we reset all option values to look like they have never been seen before.
   1023   for (auto SC : RegisteredSubCommands) {
   1024     for (auto &O : SC->OptionsMap)
   1025       O.second->reset();
   1026   }
   1027 }
   1028 
   1029 bool CommandLineParser::ParseCommandLineOptions(int argc,
   1030                                                 const char *const *argv,
   1031                                                 StringRef Overview,
   1032                                                 bool IgnoreErrors) {
   1033   assert(hasOptions() && "No options specified!");
   1034 
   1035   // Expand response files.
   1036   SmallVector<const char *, 20> newArgv(argv, argv + argc);
   1037   BumpPtrAllocator A;
   1038   StringSaver Saver(A);
   1039   ExpandResponseFiles(Saver, TokenizeGNUCommandLine, newArgv);
   1040   argv = &newArgv[0];
   1041   argc = static_cast<int>(newArgv.size());
   1042 
   1043   // Copy the program name into ProgName, making sure not to overflow it.
   1044   ProgramName = sys::path::filename(StringRef(argv[0]));
   1045 
   1046   ProgramOverview = Overview;
   1047   bool ErrorParsing = false;
   1048 
   1049   // Check out the positional arguments to collect information about them.
   1050   unsigned NumPositionalRequired = 0;
   1051 
   1052   // Determine whether or not there are an unlimited number of positionals
   1053   bool HasUnlimitedPositionals = false;
   1054 
   1055   int FirstArg = 1;
   1056   SubCommand *ChosenSubCommand = &*TopLevelSubCommand;
   1057   if (argc >= 2 && argv[FirstArg][0] != '-') {
   1058     // If the first argument specifies a valid subcommand, start processing
   1059     // options from the second argument.
   1060     ChosenSubCommand = LookupSubCommand(StringRef(argv[FirstArg]));
   1061     if (ChosenSubCommand != &*TopLevelSubCommand)
   1062       FirstArg = 2;
   1063   }
   1064   GlobalParser->ActiveSubCommand = ChosenSubCommand;
   1065 
   1066   assert(ChosenSubCommand);
   1067   auto &ConsumeAfterOpt = ChosenSubCommand->ConsumeAfterOpt;
   1068   auto &PositionalOpts = ChosenSubCommand->PositionalOpts;
   1069   auto &SinkOpts = ChosenSubCommand->SinkOpts;
   1070   auto &OptionsMap = ChosenSubCommand->OptionsMap;
   1071 
   1072   if (ConsumeAfterOpt) {
   1073     assert(PositionalOpts.size() > 0 &&
   1074            "Cannot specify cl::ConsumeAfter without a positional argument!");
   1075   }
   1076   if (!PositionalOpts.empty()) {
   1077 
   1078     // Calculate how many positional values are _required_.
   1079     bool UnboundedFound = false;
   1080     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
   1081       Option *Opt = PositionalOpts[i];
   1082       if (RequiresValue(Opt))
   1083         ++NumPositionalRequired;
   1084       else if (ConsumeAfterOpt) {
   1085         // ConsumeAfter cannot be combined with "optional" positional options
   1086         // unless there is only one positional argument...
   1087         if (PositionalOpts.size() > 1) {
   1088           if (!IgnoreErrors)
   1089             Opt->error("error - this positional option will never be matched, "
   1090                        "because it does not Require a value, and a "
   1091                        "cl::ConsumeAfter option is active!");
   1092           ErrorParsing = true;
   1093         }
   1094       } else if (UnboundedFound && !Opt->hasArgStr()) {
   1095         // This option does not "require" a value...  Make sure this option is
   1096         // not specified after an option that eats all extra arguments, or this
   1097         // one will never get any!
   1098         //
   1099         if (!IgnoreErrors) {
   1100           Opt->error("error - option can never match, because "
   1101                      "another positional argument will match an "
   1102                      "unbounded number of values, and this option"
   1103                      " does not require a value!");
   1104           errs() << ProgramName << ": CommandLine Error: Option '"
   1105                  << Opt->ArgStr << "' is all messed up!\n";
   1106           errs() << PositionalOpts.size();
   1107         }
   1108         ErrorParsing = true;
   1109       }
   1110       UnboundedFound |= EatsUnboundedNumberOfValues(Opt);
   1111     }
   1112     HasUnlimitedPositionals = UnboundedFound || ConsumeAfterOpt;
   1113   }
   1114 
   1115   // PositionalVals - A vector of "positional" arguments we accumulate into
   1116   // the process at the end.
   1117   //
   1118   SmallVector<std::pair<StringRef, unsigned>, 4> PositionalVals;
   1119 
   1120   // If the program has named positional arguments, and the name has been run
   1121   // across, keep track of which positional argument was named.  Otherwise put
   1122   // the positional args into the PositionalVals list...
   1123   Option *ActivePositionalArg = nullptr;
   1124 
   1125   // Loop over all of the arguments... processing them.
   1126   bool DashDashFound = false; // Have we read '--'?
   1127   for (int i = FirstArg; i < argc; ++i) {
   1128     Option *Handler = nullptr;
   1129     Option *NearestHandler = nullptr;
   1130     std::string NearestHandlerString;
   1131     StringRef Value;
   1132     StringRef ArgName = "";
   1133 
   1134     // Check to see if this is a positional argument.  This argument is
   1135     // considered to be positional if it doesn't start with '-', if it is "-"
   1136     // itself, or if we have seen "--" already.
   1137     //
   1138     if (argv[i][0] != '-' || argv[i][1] == 0 || DashDashFound) {
   1139       // Positional argument!
   1140       if (ActivePositionalArg) {
   1141         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
   1142         continue; // We are done!
   1143       }
   1144 
   1145       if (!PositionalOpts.empty()) {
   1146         PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
   1147 
   1148         // All of the positional arguments have been fulfulled, give the rest to
   1149         // the consume after option... if it's specified...
   1150         //
   1151         if (PositionalVals.size() >= NumPositionalRequired && ConsumeAfterOpt) {
   1152           for (++i; i < argc; ++i)
   1153             PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
   1154           break; // Handle outside of the argument processing loop...
   1155         }
   1156 
   1157         // Delay processing positional arguments until the end...
   1158         continue;
   1159       }
   1160     } else if (argv[i][0] == '-' && argv[i][1] == '-' && argv[i][2] == 0 &&
   1161                !DashDashFound) {
   1162       DashDashFound = true; // This is the mythical "--"?
   1163       continue;             // Don't try to process it as an argument itself.
   1164     } else if (ActivePositionalArg &&
   1165                (ActivePositionalArg->getMiscFlags() & PositionalEatsArgs)) {
   1166       // If there is a positional argument eating options, check to see if this
   1167       // option is another positional argument.  If so, treat it as an argument,
   1168       // otherwise feed it to the eating positional.
   1169       ArgName = StringRef(argv[i] + 1);
   1170       // Eat leading dashes.
   1171       while (!ArgName.empty() && ArgName[0] == '-')
   1172         ArgName = ArgName.substr(1);
   1173 
   1174       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
   1175       if (!Handler || Handler->getFormattingFlag() != cl::Positional) {
   1176         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
   1177         continue; // We are done!
   1178       }
   1179 
   1180     } else { // We start with a '-', must be an argument.
   1181       ArgName = StringRef(argv[i] + 1);
   1182       // Eat leading dashes.
   1183       while (!ArgName.empty() && ArgName[0] == '-')
   1184         ArgName = ArgName.substr(1);
   1185 
   1186       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
   1187 
   1188       // Check to see if this "option" is really a prefixed or grouped argument.
   1189       if (!Handler)
   1190         Handler = HandlePrefixedOrGroupedOption(ArgName, Value, ErrorParsing,
   1191                                                 OptionsMap);
   1192 
   1193       // Otherwise, look for the closest available option to report to the user
   1194       // in the upcoming error.
   1195       if (!Handler && SinkOpts.empty())
   1196         NearestHandler =
   1197             LookupNearestOption(ArgName, OptionsMap, NearestHandlerString);
   1198     }
   1199 
   1200     if (!Handler) {
   1201       if (SinkOpts.empty()) {
   1202         if (!IgnoreErrors) {
   1203           errs() << ProgramName << ": Unknown command line argument '"
   1204                  << argv[i] << "'.  Try: '" << argv[0] << " -help'\n";
   1205 
   1206           if (NearestHandler) {
   1207             // If we know a near match, report it as well.
   1208             errs() << ProgramName << ": Did you mean '-" << NearestHandlerString
   1209                    << "'?\n";
   1210           }
   1211         }
   1212 
   1213         ErrorParsing = true;
   1214       } else {
   1215         for (SmallVectorImpl<Option *>::iterator I = SinkOpts.begin(),
   1216                                                  E = SinkOpts.end();
   1217              I != E; ++I)
   1218           (*I)->addOccurrence(i, "", StringRef(argv[i]));
   1219       }
   1220       continue;
   1221     }
   1222 
   1223     // If this is a named positional argument, just remember that it is the
   1224     // active one...
   1225     if (Handler->getFormattingFlag() == cl::Positional)
   1226       ActivePositionalArg = Handler;
   1227     else
   1228       ErrorParsing |= ProvideOption(Handler, ArgName, Value, argc, argv, i);
   1229   }
   1230 
   1231   // Check and handle positional arguments now...
   1232   if (NumPositionalRequired > PositionalVals.size()) {
   1233     if (!IgnoreErrors) {
   1234       errs() << ProgramName
   1235              << ": Not enough positional command line arguments specified!\n"
   1236              << "Must specify at least " << NumPositionalRequired
   1237              << " positional argument" << (NumPositionalRequired > 1 ? "s" : "")
   1238              << ": See: " << argv[0] << " - help\n";
   1239     }
   1240 
   1241     ErrorParsing = true;
   1242   } else if (!HasUnlimitedPositionals &&
   1243              PositionalVals.size() > PositionalOpts.size()) {
   1244     if (!IgnoreErrors) {
   1245       errs() << ProgramName << ": Too many positional arguments specified!\n"
   1246              << "Can specify at most " << PositionalOpts.size()
   1247              << " positional arguments: See: " << argv[0] << " -help\n";
   1248     }
   1249     ErrorParsing = true;
   1250 
   1251   } else if (!ConsumeAfterOpt) {
   1252     // Positional args have already been handled if ConsumeAfter is specified.
   1253     unsigned ValNo = 0, NumVals = static_cast<unsigned>(PositionalVals.size());
   1254     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
   1255       if (RequiresValue(PositionalOpts[i])) {
   1256         ProvidePositionalOption(PositionalOpts[i], PositionalVals[ValNo].first,
   1257                                 PositionalVals[ValNo].second);
   1258         ValNo++;
   1259         --NumPositionalRequired; // We fulfilled our duty...
   1260       }
   1261 
   1262       // If we _can_ give this option more arguments, do so now, as long as we
   1263       // do not give it values that others need.  'Done' controls whether the
   1264       // option even _WANTS_ any more.
   1265       //
   1266       bool Done = PositionalOpts[i]->getNumOccurrencesFlag() == cl::Required;
   1267       while (NumVals - ValNo > NumPositionalRequired && !Done) {
   1268         switch (PositionalOpts[i]->getNumOccurrencesFlag()) {
   1269         case cl::Optional:
   1270           Done = true; // Optional arguments want _at most_ one value
   1271           LLVM_FALLTHROUGH;
   1272         case cl::ZeroOrMore: // Zero or more will take all they can get...
   1273         case cl::OneOrMore:  // One or more will take all they can get...
   1274           ProvidePositionalOption(PositionalOpts[i],
   1275                                   PositionalVals[ValNo].first,
   1276                                   PositionalVals[ValNo].second);
   1277           ValNo++;
   1278           break;
   1279         default:
   1280           llvm_unreachable("Internal error, unexpected NumOccurrences flag in "
   1281                            "positional argument processing!");
   1282         }
   1283       }
   1284     }
   1285   } else {
   1286     assert(ConsumeAfterOpt && NumPositionalRequired <= PositionalVals.size());
   1287     unsigned ValNo = 0;
   1288     for (size_t j = 1, e = PositionalOpts.size(); j != e; ++j)
   1289       if (RequiresValue(PositionalOpts[j])) {
   1290         ErrorParsing |= ProvidePositionalOption(PositionalOpts[j],
   1291                                                 PositionalVals[ValNo].first,
   1292                                                 PositionalVals[ValNo].second);
   1293         ValNo++;
   1294       }
   1295 
   1296     // Handle the case where there is just one positional option, and it's
   1297     // optional.  In this case, we want to give JUST THE FIRST option to the
   1298     // positional option and keep the rest for the consume after.  The above
   1299     // loop would have assigned no values to positional options in this case.
   1300     //
   1301     if (PositionalOpts.size() == 1 && ValNo == 0 && !PositionalVals.empty()) {
   1302       ErrorParsing |= ProvidePositionalOption(PositionalOpts[0],
   1303                                               PositionalVals[ValNo].first,
   1304                                               PositionalVals[ValNo].second);
   1305       ValNo++;
   1306     }
   1307 
   1308     // Handle over all of the rest of the arguments to the
   1309     // cl::ConsumeAfter command line option...
   1310     for (; ValNo != PositionalVals.size(); ++ValNo)
   1311       ErrorParsing |=
   1312           ProvidePositionalOption(ConsumeAfterOpt, PositionalVals[ValNo].first,
   1313                                   PositionalVals[ValNo].second);
   1314   }
   1315 
   1316   // Loop over args and make sure all required args are specified!
   1317   for (const auto &Opt : OptionsMap) {
   1318     switch (Opt.second->getNumOccurrencesFlag()) {
   1319     case Required:
   1320     case OneOrMore:
   1321       if (Opt.second->getNumOccurrences() == 0) {
   1322         Opt.second->error("must be specified at least once!");
   1323         ErrorParsing = true;
   1324       }
   1325       LLVM_FALLTHROUGH;
   1326     default:
   1327       break;
   1328     }
   1329   }
   1330 
   1331   // Now that we know if -debug is specified, we can use it.
   1332   // Note that if ReadResponseFiles == true, this must be done before the
   1333   // memory allocated for the expanded command line is free()d below.
   1334   DEBUG(dbgs() << "Args: ";
   1335         for (int i = 0; i < argc; ++i) dbgs() << argv[i] << ' ';
   1336         dbgs() << '\n';);
   1337 
   1338   // Free all of the memory allocated to the map.  Command line options may only
   1339   // be processed once!
   1340   MoreHelp.clear();
   1341 
   1342   // If we had an error processing our arguments, don't let the program execute
   1343   if (ErrorParsing) {
   1344     if (!IgnoreErrors)
   1345       exit(1);
   1346     return false;
   1347   }
   1348   return true;
   1349 }
   1350 
   1351 //===----------------------------------------------------------------------===//
   1352 // Option Base class implementation
   1353 //
   1354 
   1355 bool Option::error(const Twine &Message, StringRef ArgName) {
   1356   if (!ArgName.data())
   1357     ArgName = ArgStr;
   1358   if (ArgName.empty())
   1359     errs() << HelpStr; // Be nice for positional arguments
   1360   else
   1361     errs() << GlobalParser->ProgramName << ": for the -" << ArgName;
   1362 
   1363   errs() << " option: " << Message << "\n";
   1364   return true;
   1365 }
   1366 
   1367 bool Option::addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
   1368                            bool MultiArg) {
   1369   if (!MultiArg)
   1370     NumOccurrences++; // Increment the number of times we have been seen
   1371 
   1372   switch (getNumOccurrencesFlag()) {
   1373   case Optional:
   1374     if (NumOccurrences > 1)
   1375       return error("may only occur zero or one times!", ArgName);
   1376     break;
   1377   case Required:
   1378     if (NumOccurrences > 1)
   1379       return error("must occur exactly one time!", ArgName);
   1380     LLVM_FALLTHROUGH;
   1381   case OneOrMore:
   1382   case ZeroOrMore:
   1383   case ConsumeAfter:
   1384     break;
   1385   }
   1386 
   1387   return handleOccurrence(pos, ArgName, Value);
   1388 }
   1389 
   1390 // getValueStr - Get the value description string, using "DefaultMsg" if nothing
   1391 // has been specified yet.
   1392 //
   1393 static StringRef getValueStr(const Option &O, StringRef DefaultMsg) {
   1394   if (O.ValueStr.empty())
   1395     return DefaultMsg;
   1396   return O.ValueStr;
   1397 }
   1398 
   1399 //===----------------------------------------------------------------------===//
   1400 // cl::alias class implementation
   1401 //
   1402 
   1403 // Return the width of the option tag for printing...
   1404 size_t alias::getOptionWidth() const { return ArgStr.size() + 6; }
   1405 
   1406 static void printHelpStr(StringRef HelpStr, size_t Indent,
   1407                          size_t FirstLineIndentedBy) {
   1408   std::pair<StringRef, StringRef> Split = HelpStr.split('\n');
   1409   outs().indent(Indent - FirstLineIndentedBy) << " - " << Split.first << "\n";
   1410   while (!Split.second.empty()) {
   1411     Split = Split.second.split('\n');
   1412     outs().indent(Indent) << Split.first << "\n";
   1413   }
   1414 }
   1415 
   1416 // Print out the option for the alias.
   1417 void alias::printOptionInfo(size_t GlobalWidth) const {
   1418   outs() << "  -" << ArgStr;
   1419   printHelpStr(HelpStr, GlobalWidth, ArgStr.size() + 6);
   1420 }
   1421 
   1422 //===----------------------------------------------------------------------===//
   1423 // Parser Implementation code...
   1424 //
   1425 
   1426 // basic_parser implementation
   1427 //
   1428 
   1429 // Return the width of the option tag for printing...
   1430 size_t basic_parser_impl::getOptionWidth(const Option &O) const {
   1431   size_t Len = O.ArgStr.size();
   1432   auto ValName = getValueName();
   1433   if (!ValName.empty())
   1434     Len += getValueStr(O, ValName).size() + 3;
   1435 
   1436   return Len + 6;
   1437 }
   1438 
   1439 // printOptionInfo - Print out information about this option.  The
   1440 // to-be-maintained width is specified.
   1441 //
   1442 void basic_parser_impl::printOptionInfo(const Option &O,
   1443                                         size_t GlobalWidth) const {
   1444   outs() << "  -" << O.ArgStr;
   1445 
   1446   auto ValName = getValueName();
   1447   if (!ValName.empty())
   1448     outs() << "=<" << getValueStr(O, ValName) << '>';
   1449 
   1450   printHelpStr(O.HelpStr, GlobalWidth, getOptionWidth(O));
   1451 }
   1452 
   1453 void basic_parser_impl::printOptionName(const Option &O,
   1454                                         size_t GlobalWidth) const {
   1455   outs() << "  -" << O.ArgStr;
   1456   outs().indent(GlobalWidth - O.ArgStr.size());
   1457 }
   1458 
   1459 // parser<bool> implementation
   1460 //
   1461 bool parser<bool>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1462                          bool &Value) {
   1463   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
   1464       Arg == "1") {
   1465     Value = true;
   1466     return false;
   1467   }
   1468 
   1469   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
   1470     Value = false;
   1471     return false;
   1472   }
   1473   return O.error("'" + Arg +
   1474                  "' is invalid value for boolean argument! Try 0 or 1");
   1475 }
   1476 
   1477 // parser<boolOrDefault> implementation
   1478 //
   1479 bool parser<boolOrDefault>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1480                                   boolOrDefault &Value) {
   1481   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
   1482       Arg == "1") {
   1483     Value = BOU_TRUE;
   1484     return false;
   1485   }
   1486   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
   1487     Value = BOU_FALSE;
   1488     return false;
   1489   }
   1490 
   1491   return O.error("'" + Arg +
   1492                  "' is invalid value for boolean argument! Try 0 or 1");
   1493 }
   1494 
   1495 // parser<int> implementation
   1496 //
   1497 bool parser<int>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1498                         int &Value) {
   1499   if (Arg.getAsInteger(0, Value))
   1500     return O.error("'" + Arg + "' value invalid for integer argument!");
   1501   return false;
   1502 }
   1503 
   1504 // parser<unsigned> implementation
   1505 //
   1506 bool parser<unsigned>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1507                              unsigned &Value) {
   1508 
   1509   if (Arg.getAsInteger(0, Value))
   1510     return O.error("'" + Arg + "' value invalid for uint argument!");
   1511   return false;
   1512 }
   1513 
   1514 // parser<unsigned long long> implementation
   1515 //
   1516 bool parser<unsigned long long>::parse(Option &O, StringRef ArgName,
   1517                                        StringRef Arg,
   1518                                        unsigned long long &Value) {
   1519 
   1520   if (Arg.getAsInteger(0, Value))
   1521     return O.error("'" + Arg + "' value invalid for uint argument!");
   1522   return false;
   1523 }
   1524 
   1525 // parser<double>/parser<float> implementation
   1526 //
   1527 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
   1528   SmallString<32> TmpStr(Arg.begin(), Arg.end());
   1529   const char *ArgStart = TmpStr.c_str();
   1530   char *End;
   1531   Value = strtod(ArgStart, &End);
   1532   if (*End != 0)
   1533     return O.error("'" + Arg + "' value invalid for floating point argument!");
   1534   return false;
   1535 }
   1536 
   1537 bool parser<double>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1538                            double &Val) {
   1539   return parseDouble(O, Arg, Val);
   1540 }
   1541 
   1542 bool parser<float>::parse(Option &O, StringRef ArgName, StringRef Arg,
   1543                           float &Val) {
   1544   double dVal;
   1545   if (parseDouble(O, Arg, dVal))
   1546     return true;
   1547   Val = (float)dVal;
   1548   return false;
   1549 }
   1550 
   1551 // generic_parser_base implementation
   1552 //
   1553 
   1554 // findOption - Return the option number corresponding to the specified
   1555 // argument string.  If the option is not found, getNumOptions() is returned.
   1556 //
   1557 unsigned generic_parser_base::findOption(StringRef Name) {
   1558   unsigned e = getNumOptions();
   1559 
   1560   for (unsigned i = 0; i != e; ++i) {
   1561     if (getOption(i) == Name)
   1562       return i;
   1563   }
   1564   return e;
   1565 }
   1566 
   1567 // Return the width of the option tag for printing...
   1568 size_t generic_parser_base::getOptionWidth(const Option &O) const {
   1569   if (O.hasArgStr()) {
   1570     size_t Size = O.ArgStr.size() + 6;
   1571     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
   1572       Size = std::max(Size, getOption(i).size() + 8);
   1573     return Size;
   1574   } else {
   1575     size_t BaseSize = 0;
   1576     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
   1577       BaseSize = std::max(BaseSize, getOption(i).size() + 8);
   1578     return BaseSize;
   1579   }
   1580 }
   1581 
   1582 // printOptionInfo - Print out information about this option.  The
   1583 // to-be-maintained width is specified.
   1584 //
   1585 void generic_parser_base::printOptionInfo(const Option &O,
   1586                                           size_t GlobalWidth) const {
   1587   if (O.hasArgStr()) {
   1588     outs() << "  -" << O.ArgStr;
   1589     printHelpStr(O.HelpStr, GlobalWidth, O.ArgStr.size() + 6);
   1590 
   1591     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
   1592       size_t NumSpaces = GlobalWidth - getOption(i).size() - 8;
   1593       outs() << "    =" << getOption(i);
   1594       outs().indent(NumSpaces) << " -   " << getDescription(i) << '\n';
   1595     }
   1596   } else {
   1597     if (!O.HelpStr.empty())
   1598       outs() << "  " << O.HelpStr << '\n';
   1599     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
   1600       auto Option = getOption(i);
   1601       outs() << "    -" << Option;
   1602       printHelpStr(getDescription(i), GlobalWidth, Option.size() + 8);
   1603     }
   1604   }
   1605 }
   1606 
   1607 static const size_t MaxOptWidth = 8; // arbitrary spacing for printOptionDiff
   1608 
   1609 // printGenericOptionDiff - Print the value of this option and it's default.
   1610 //
   1611 // "Generic" options have each value mapped to a name.
   1612 void generic_parser_base::printGenericOptionDiff(
   1613     const Option &O, const GenericOptionValue &Value,
   1614     const GenericOptionValue &Default, size_t GlobalWidth) const {
   1615   outs() << "  -" << O.ArgStr;
   1616   outs().indent(GlobalWidth - O.ArgStr.size());
   1617 
   1618   unsigned NumOpts = getNumOptions();
   1619   for (unsigned i = 0; i != NumOpts; ++i) {
   1620     if (Value.compare(getOptionValue(i)))
   1621       continue;
   1622 
   1623     outs() << "= " << getOption(i);
   1624     size_t L = getOption(i).size();
   1625     size_t NumSpaces = MaxOptWidth > L ? MaxOptWidth - L : 0;
   1626     outs().indent(NumSpaces) << " (default: ";
   1627     for (unsigned j = 0; j != NumOpts; ++j) {
   1628       if (Default.compare(getOptionValue(j)))
   1629         continue;
   1630       outs() << getOption(j);
   1631       break;
   1632     }
   1633     outs() << ")\n";
   1634     return;
   1635   }
   1636   outs() << "= *unknown option value*\n";
   1637 }
   1638 
   1639 // printOptionDiff - Specializations for printing basic value types.
   1640 //
   1641 #define PRINT_OPT_DIFF(T)                                                      \
   1642   void parser<T>::printOptionDiff(const Option &O, T V, OptionValue<T> D,      \
   1643                                   size_t GlobalWidth) const {                  \
   1644     printOptionName(O, GlobalWidth);                                           \
   1645     std::string Str;                                                           \
   1646     {                                                                          \
   1647       raw_string_ostream SS(Str);                                              \
   1648       SS << V;                                                                 \
   1649     }                                                                          \
   1650     outs() << "= " << Str;                                                     \
   1651     size_t NumSpaces =                                                         \
   1652         MaxOptWidth > Str.size() ? MaxOptWidth - Str.size() : 0;               \
   1653     outs().indent(NumSpaces) << " (default: ";                                 \
   1654     if (D.hasValue())                                                          \
   1655       outs() << D.getValue();                                                  \
   1656     else                                                                       \
   1657       outs() << "*no default*";                                                \
   1658     outs() << ")\n";                                                           \
   1659   }
   1660 
   1661 PRINT_OPT_DIFF(bool)
   1662 PRINT_OPT_DIFF(boolOrDefault)
   1663 PRINT_OPT_DIFF(int)
   1664 PRINT_OPT_DIFF(unsigned)
   1665 PRINT_OPT_DIFF(unsigned long long)
   1666 PRINT_OPT_DIFF(double)
   1667 PRINT_OPT_DIFF(float)
   1668 PRINT_OPT_DIFF(char)
   1669 
   1670 void parser<std::string>::printOptionDiff(const Option &O, StringRef V,
   1671                                           const OptionValue<std::string> &D,
   1672                                           size_t GlobalWidth) const {
   1673   printOptionName(O, GlobalWidth);
   1674   outs() << "= " << V;
   1675   size_t NumSpaces = MaxOptWidth > V.size() ? MaxOptWidth - V.size() : 0;
   1676   outs().indent(NumSpaces) << " (default: ";
   1677   if (D.hasValue())
   1678     outs() << D.getValue();
   1679   else
   1680     outs() << "*no default*";
   1681   outs() << ")\n";
   1682 }
   1683 
   1684 // Print a placeholder for options that don't yet support printOptionDiff().
   1685 void basic_parser_impl::printOptionNoValue(const Option &O,
   1686                                            size_t GlobalWidth) const {
   1687   printOptionName(O, GlobalWidth);
   1688   outs() << "= *cannot print option value*\n";
   1689 }
   1690 
   1691 //===----------------------------------------------------------------------===//
   1692 // -help and -help-hidden option implementation
   1693 //
   1694 
   1695 static int OptNameCompare(const std::pair<const char *, Option *> *LHS,
   1696                           const std::pair<const char *, Option *> *RHS) {
   1697   return strcmp(LHS->first, RHS->first);
   1698 }
   1699 
   1700 static int SubNameCompare(const std::pair<const char *, SubCommand *> *LHS,
   1701                           const std::pair<const char *, SubCommand *> *RHS) {
   1702   return strcmp(LHS->first, RHS->first);
   1703 }
   1704 
   1705 // Copy Options into a vector so we can sort them as we like.
   1706 static void sortOpts(StringMap<Option *> &OptMap,
   1707                      SmallVectorImpl<std::pair<const char *, Option *>> &Opts,
   1708                      bool ShowHidden) {
   1709   SmallPtrSet<Option *, 32> OptionSet; // Duplicate option detection.
   1710 
   1711   for (StringMap<Option *>::iterator I = OptMap.begin(), E = OptMap.end();
   1712        I != E; ++I) {
   1713     // Ignore really-hidden options.
   1714     if (I->second->getOptionHiddenFlag() == ReallyHidden)
   1715       continue;
   1716 
   1717     // Unless showhidden is set, ignore hidden flags.
   1718     if (I->second->getOptionHiddenFlag() == Hidden && !ShowHidden)
   1719       continue;
   1720 
   1721     // If we've already seen this option, don't add it to the list again.
   1722     if (!OptionSet.insert(I->second).second)
   1723       continue;
   1724 
   1725     Opts.push_back(
   1726         std::pair<const char *, Option *>(I->getKey().data(), I->second));
   1727   }
   1728 
   1729   // Sort the options list alphabetically.
   1730   array_pod_sort(Opts.begin(), Opts.end(), OptNameCompare);
   1731 }
   1732 
   1733 static void
   1734 sortSubCommands(const SmallPtrSetImpl<SubCommand *> &SubMap,
   1735                 SmallVectorImpl<std::pair<const char *, SubCommand *>> &Subs) {
   1736   for (const auto &S : SubMap) {
   1737     if (S->getName().empty())
   1738       continue;
   1739     Subs.push_back(std::make_pair(S->getName().data(), S));
   1740   }
   1741   array_pod_sort(Subs.begin(), Subs.end(), SubNameCompare);
   1742 }
   1743 
   1744 namespace {
   1745 
   1746 class HelpPrinter {
   1747 protected:
   1748   const bool ShowHidden;
   1749   typedef SmallVector<std::pair<const char *, Option *>, 128>
   1750       StrOptionPairVector;
   1751   typedef SmallVector<std::pair<const char *, SubCommand *>, 128>
   1752       StrSubCommandPairVector;
   1753   // Print the options. Opts is assumed to be alphabetically sorted.
   1754   virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
   1755     for (size_t i = 0, e = Opts.size(); i != e; ++i)
   1756       Opts[i].second->printOptionInfo(MaxArgLen);
   1757   }
   1758 
   1759   void printSubCommands(StrSubCommandPairVector &Subs, size_t MaxSubLen) {
   1760     for (const auto &S : Subs) {
   1761       outs() << "  " << S.first;
   1762       if (!S.second->getDescription().empty()) {
   1763         outs().indent(MaxSubLen - strlen(S.first));
   1764         outs() << " - " << S.second->getDescription();
   1765       }
   1766       outs() << "\n";
   1767     }
   1768   }
   1769 
   1770 public:
   1771   explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {}
   1772   virtual ~HelpPrinter() {}
   1773 
   1774   // Invoke the printer.
   1775   void operator=(bool Value) {
   1776     if (!Value)
   1777       return;
   1778 
   1779     SubCommand *Sub = GlobalParser->getActiveSubCommand();
   1780     auto &OptionsMap = Sub->OptionsMap;
   1781     auto &PositionalOpts = Sub->PositionalOpts;
   1782     auto &ConsumeAfterOpt = Sub->ConsumeAfterOpt;
   1783 
   1784     StrOptionPairVector Opts;
   1785     sortOpts(OptionsMap, Opts, ShowHidden);
   1786 
   1787     StrSubCommandPairVector Subs;
   1788     sortSubCommands(GlobalParser->RegisteredSubCommands, Subs);
   1789 
   1790     if (!GlobalParser->ProgramOverview.empty())
   1791       outs() << "OVERVIEW: " << GlobalParser->ProgramOverview << "\n";
   1792 
   1793     if (Sub == &*TopLevelSubCommand) {
   1794       outs() << "USAGE: " << GlobalParser->ProgramName;
   1795       if (Subs.size() > 2)
   1796         outs() << " [subcommand]";
   1797       outs() << " [options]";
   1798     } else {
   1799       if (!Sub->getDescription().empty()) {
   1800         outs() << "SUBCOMMAND '" << Sub->getName()
   1801                << "': " << Sub->getDescription() << "\n\n";
   1802       }
   1803       outs() << "USAGE: " << GlobalParser->ProgramName << " " << Sub->getName()
   1804              << " [options]";
   1805     }
   1806 
   1807     for (auto Opt : PositionalOpts) {
   1808       if (Opt->hasArgStr())
   1809         outs() << " --" << Opt->ArgStr;
   1810       outs() << " " << Opt->HelpStr;
   1811     }
   1812 
   1813     // Print the consume after option info if it exists...
   1814     if (ConsumeAfterOpt)
   1815       outs() << " " << ConsumeAfterOpt->HelpStr;
   1816 
   1817     if (Sub == &*TopLevelSubCommand && !Subs.empty()) {
   1818       // Compute the maximum subcommand length...
   1819       size_t MaxSubLen = 0;
   1820       for (size_t i = 0, e = Subs.size(); i != e; ++i)
   1821         MaxSubLen = std::max(MaxSubLen, strlen(Subs[i].first));
   1822 
   1823       outs() << "\n\n";
   1824       outs() << "SUBCOMMANDS:\n\n";
   1825       printSubCommands(Subs, MaxSubLen);
   1826       outs() << "\n";
   1827       outs() << "  Type \"" << GlobalParser->ProgramName
   1828              << " <subcommand> -help\" to get more help on a specific "
   1829                 "subcommand";
   1830     }
   1831 
   1832     outs() << "\n\n";
   1833 
   1834     // Compute the maximum argument length...
   1835     size_t MaxArgLen = 0;
   1836     for (size_t i = 0, e = Opts.size(); i != e; ++i)
   1837       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
   1838 
   1839     outs() << "OPTIONS:\n";
   1840     printOptions(Opts, MaxArgLen);
   1841 
   1842     // Print any extra help the user has declared.
   1843     for (auto I : GlobalParser->MoreHelp)
   1844       outs() << I;
   1845     GlobalParser->MoreHelp.clear();
   1846 
   1847     // Halt the program since help information was printed
   1848     exit(0);
   1849   }
   1850 };
   1851 
   1852 class CategorizedHelpPrinter : public HelpPrinter {
   1853 public:
   1854   explicit CategorizedHelpPrinter(bool showHidden) : HelpPrinter(showHidden) {}
   1855 
   1856   // Helper function for printOptions().
   1857   // It shall return a negative value if A's name should be lexicographically
   1858   // ordered before B's name. It returns a value greater equal zero otherwise.
   1859   static int OptionCategoryCompare(OptionCategory *const *A,
   1860                                    OptionCategory *const *B) {
   1861     return (*A)->getName() == (*B)->getName();
   1862   }
   1863 
   1864   // Make sure we inherit our base class's operator=()
   1865   using HelpPrinter::operator=;
   1866 
   1867 protected:
   1868   void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) override {
   1869     std::vector<OptionCategory *> SortedCategories;
   1870     std::map<OptionCategory *, std::vector<Option *>> CategorizedOptions;
   1871 
   1872     // Collect registered option categories into vector in preparation for
   1873     // sorting.
   1874     for (auto I = GlobalParser->RegisteredOptionCategories.begin(),
   1875               E = GlobalParser->RegisteredOptionCategories.end();
   1876          I != E; ++I) {
   1877       SortedCategories.push_back(*I);
   1878     }
   1879 
   1880     // Sort the different option categories alphabetically.
   1881     assert(SortedCategories.size() > 0 && "No option categories registered!");
   1882     array_pod_sort(SortedCategories.begin(), SortedCategories.end(),
   1883                    OptionCategoryCompare);
   1884 
   1885     // Create map to empty vectors.
   1886     for (std::vector<OptionCategory *>::const_iterator
   1887              I = SortedCategories.begin(),
   1888              E = SortedCategories.end();
   1889          I != E; ++I)
   1890       CategorizedOptions[*I] = std::vector<Option *>();
   1891 
   1892     // Walk through pre-sorted options and assign into categories.
   1893     // Because the options are already alphabetically sorted the
   1894     // options within categories will also be alphabetically sorted.
   1895     for (size_t I = 0, E = Opts.size(); I != E; ++I) {
   1896       Option *Opt = Opts[I].second;
   1897       assert(CategorizedOptions.count(Opt->Category) > 0 &&
   1898              "Option has an unregistered category");
   1899       CategorizedOptions[Opt->Category].push_back(Opt);
   1900     }
   1901 
   1902     // Now do printing.
   1903     for (std::vector<OptionCategory *>::const_iterator
   1904              Category = SortedCategories.begin(),
   1905              E = SortedCategories.end();
   1906          Category != E; ++Category) {
   1907       // Hide empty categories for -help, but show for -help-hidden.
   1908       const auto &CategoryOptions = CategorizedOptions[*Category];
   1909       bool IsEmptyCategory = CategoryOptions.empty();
   1910       if (!ShowHidden && IsEmptyCategory)
   1911         continue;
   1912 
   1913       // Print category information.
   1914       outs() << "\n";
   1915       outs() << (*Category)->getName() << ":\n";
   1916 
   1917       // Check if description is set.
   1918       if (!(*Category)->getDescription().empty())
   1919         outs() << (*Category)->getDescription() << "\n\n";
   1920       else
   1921         outs() << "\n";
   1922 
   1923       // When using -help-hidden explicitly state if the category has no
   1924       // options associated with it.
   1925       if (IsEmptyCategory) {
   1926         outs() << "  This option category has no options.\n";
   1927         continue;
   1928       }
   1929       // Loop over the options in the category and print.
   1930       for (const Option *Opt : CategoryOptions)
   1931         Opt->printOptionInfo(MaxArgLen);
   1932     }
   1933   }
   1934 };
   1935 
   1936 // This wraps the Uncategorizing and Categorizing printers and decides
   1937 // at run time which should be invoked.
   1938 class HelpPrinterWrapper {
   1939 private:
   1940   HelpPrinter &UncategorizedPrinter;
   1941   CategorizedHelpPrinter &CategorizedPrinter;
   1942 
   1943 public:
   1944   explicit HelpPrinterWrapper(HelpPrinter &UncategorizedPrinter,
   1945                               CategorizedHelpPrinter &CategorizedPrinter)
   1946       : UncategorizedPrinter(UncategorizedPrinter),
   1947         CategorizedPrinter(CategorizedPrinter) {}
   1948 
   1949   // Invoke the printer.
   1950   void operator=(bool Value);
   1951 };
   1952 
   1953 } // End anonymous namespace
   1954 
   1955 // Declare the four HelpPrinter instances that are used to print out help, or
   1956 // help-hidden as an uncategorized list or in categories.
   1957 static HelpPrinter UncategorizedNormalPrinter(false);
   1958 static HelpPrinter UncategorizedHiddenPrinter(true);
   1959 static CategorizedHelpPrinter CategorizedNormalPrinter(false);
   1960 static CategorizedHelpPrinter CategorizedHiddenPrinter(true);
   1961 
   1962 // Declare HelpPrinter wrappers that will decide whether or not to invoke
   1963 // a categorizing help printer
   1964 static HelpPrinterWrapper WrappedNormalPrinter(UncategorizedNormalPrinter,
   1965                                                CategorizedNormalPrinter);
   1966 static HelpPrinterWrapper WrappedHiddenPrinter(UncategorizedHiddenPrinter,
   1967                                                CategorizedHiddenPrinter);
   1968 
   1969 // Define a category for generic options that all tools should have.
   1970 static cl::OptionCategory GenericCategory("Generic Options");
   1971 
   1972 // Define uncategorized help printers.
   1973 // -help-list is hidden by default because if Option categories are being used
   1974 // then -help behaves the same as -help-list.
   1975 static cl::opt<HelpPrinter, true, parser<bool>> HLOp(
   1976     "help-list",
   1977     cl::desc("Display list of available options (-help-list-hidden for more)"),
   1978     cl::location(UncategorizedNormalPrinter), cl::Hidden, cl::ValueDisallowed,
   1979     cl::cat(GenericCategory), cl::sub(*AllSubCommands));
   1980 
   1981 static cl::opt<HelpPrinter, true, parser<bool>>
   1982     HLHOp("help-list-hidden", cl::desc("Display list of all available options"),
   1983           cl::location(UncategorizedHiddenPrinter), cl::Hidden,
   1984           cl::ValueDisallowed, cl::cat(GenericCategory),
   1985           cl::sub(*AllSubCommands));
   1986 
   1987 // Define uncategorized/categorized help printers. These printers change their
   1988 // behaviour at runtime depending on whether one or more Option categories have
   1989 // been declared.
   1990 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
   1991     HOp("help", cl::desc("Display available options (-help-hidden for more)"),
   1992         cl::location(WrappedNormalPrinter), cl::ValueDisallowed,
   1993         cl::cat(GenericCategory), cl::sub(*AllSubCommands));
   1994 
   1995 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
   1996     HHOp("help-hidden", cl::desc("Display all available options"),
   1997          cl::location(WrappedHiddenPrinter), cl::Hidden, cl::ValueDisallowed,
   1998          cl::cat(GenericCategory), cl::sub(*AllSubCommands));
   1999 
   2000 static cl::opt<bool> PrintOptions(
   2001     "print-options",
   2002     cl::desc("Print non-default options after command line parsing"),
   2003     cl::Hidden, cl::init(false), cl::cat(GenericCategory),
   2004     cl::sub(*AllSubCommands));
   2005 
   2006 static cl::opt<bool> PrintAllOptions(
   2007     "print-all-options",
   2008     cl::desc("Print all option values after command line parsing"), cl::Hidden,
   2009     cl::init(false), cl::cat(GenericCategory), cl::sub(*AllSubCommands));
   2010 
   2011 void HelpPrinterWrapper::operator=(bool Value) {
   2012   if (!Value)
   2013     return;
   2014 
   2015   // Decide which printer to invoke. If more than one option category is
   2016   // registered then it is useful to show the categorized help instead of
   2017   // uncategorized help.
   2018   if (GlobalParser->RegisteredOptionCategories.size() > 1) {
   2019     // unhide -help-list option so user can have uncategorized output if they
   2020     // want it.
   2021     HLOp.setHiddenFlag(NotHidden);
   2022 
   2023     CategorizedPrinter = true; // Invoke categorized printer
   2024   } else
   2025     UncategorizedPrinter = true; // Invoke uncategorized printer
   2026 }
   2027 
   2028 // Print the value of each option.
   2029 void cl::PrintOptionValues() { GlobalParser->printOptionValues(); }
   2030 
   2031 void CommandLineParser::printOptionValues() {
   2032   if (!PrintOptions && !PrintAllOptions)
   2033     return;
   2034 
   2035   SmallVector<std::pair<const char *, Option *>, 128> Opts;
   2036   sortOpts(ActiveSubCommand->OptionsMap, Opts, /*ShowHidden*/ true);
   2037 
   2038   // Compute the maximum argument length...
   2039   size_t MaxArgLen = 0;
   2040   for (size_t i = 0, e = Opts.size(); i != e; ++i)
   2041     MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
   2042 
   2043   for (size_t i = 0, e = Opts.size(); i != e; ++i)
   2044     Opts[i].second->printOptionValue(MaxArgLen, PrintAllOptions);
   2045 }
   2046 
   2047 static void (*OverrideVersionPrinter)() = nullptr;
   2048 
   2049 static std::vector<void (*)()> *ExtraVersionPrinters = nullptr;
   2050 
   2051 namespace {
   2052 class VersionPrinter {
   2053 public:
   2054   void print() {
   2055     raw_ostream &OS = outs();
   2056 #ifdef PACKAGE_VENDOR
   2057     OS << PACKAGE_VENDOR << " ";
   2058 #else
   2059     OS << "LLVM (http://llvm.org/):\n  ";
   2060 #endif
   2061     OS << PACKAGE_NAME << " version " << PACKAGE_VERSION;
   2062 #ifdef LLVM_VERSION_INFO
   2063     OS << " " << LLVM_VERSION_INFO;
   2064 #endif
   2065     OS << "\n  ";
   2066 #ifndef __OPTIMIZE__
   2067     OS << "DEBUG build";
   2068 #else
   2069     OS << "Optimized build";
   2070 #endif
   2071 #ifndef NDEBUG
   2072     OS << " with assertions";
   2073 #endif
   2074     std::string CPU = sys::getHostCPUName();
   2075     if (CPU == "generic")
   2076       CPU = "(unknown)";
   2077     OS << ".\n"
   2078        << "  Default target: " << sys::getDefaultTargetTriple() << '\n'
   2079        << "  Host CPU: " << CPU << '\n';
   2080   }
   2081   void operator=(bool OptionWasSpecified) {
   2082     if (!OptionWasSpecified)
   2083       return;
   2084 
   2085     if (OverrideVersionPrinter != nullptr) {
   2086       (*OverrideVersionPrinter)();
   2087       exit(0);
   2088     }
   2089     print();
   2090 
   2091     // Iterate over any registered extra printers and call them to add further
   2092     // information.
   2093     if (ExtraVersionPrinters != nullptr) {
   2094       outs() << '\n';
   2095       for (std::vector<void (*)()>::iterator I = ExtraVersionPrinters->begin(),
   2096                                              E = ExtraVersionPrinters->end();
   2097            I != E; ++I)
   2098         (*I)();
   2099     }
   2100 
   2101     exit(0);
   2102   }
   2103 };
   2104 } // End anonymous namespace
   2105 
   2106 // Define the --version option that prints out the LLVM version for the tool
   2107 static VersionPrinter VersionPrinterInstance;
   2108 
   2109 static cl::opt<VersionPrinter, true, parser<bool>>
   2110     VersOp("version", cl::desc("Display the version of this program"),
   2111            cl::location(VersionPrinterInstance), cl::ValueDisallowed,
   2112            cl::cat(GenericCategory));
   2113 
   2114 // Utility function for printing the help message.
   2115 void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
   2116   // This looks weird, but it actually prints the help message. The Printers are
   2117   // types of HelpPrinter and the help gets printed when its operator= is
   2118   // invoked. That's because the "normal" usages of the help printer is to be
   2119   // assigned true/false depending on whether -help or -help-hidden was given or
   2120   // not.  Since we're circumventing that we have to make it look like -help or
   2121   // -help-hidden were given, so we assign true.
   2122 
   2123   if (!Hidden && !Categorized)
   2124     UncategorizedNormalPrinter = true;
   2125   else if (!Hidden && Categorized)
   2126     CategorizedNormalPrinter = true;
   2127   else if (Hidden && !Categorized)
   2128     UncategorizedHiddenPrinter = true;
   2129   else
   2130     CategorizedHiddenPrinter = true;
   2131 }
   2132 
   2133 /// Utility function for printing version number.
   2134 void cl::PrintVersionMessage() { VersionPrinterInstance.print(); }
   2135 
   2136 void cl::SetVersionPrinter(void (*func)()) { OverrideVersionPrinter = func; }
   2137 
   2138 void cl::AddExtraVersionPrinter(void (*func)()) {
   2139   if (!ExtraVersionPrinters)
   2140     ExtraVersionPrinters = new std::vector<void (*)()>;
   2141 
   2142   ExtraVersionPrinters->push_back(func);
   2143 }
   2144 
   2145 StringMap<Option *> &cl::getRegisteredOptions(SubCommand &Sub) {
   2146   auto &Subs = GlobalParser->RegisteredSubCommands;
   2147   (void)Subs;
   2148   assert(is_contained(Subs, &Sub));
   2149   return Sub.OptionsMap;
   2150 }
   2151 
   2152 iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
   2153 cl::getRegisteredSubcommands() {
   2154   return GlobalParser->getRegisteredSubcommands();
   2155 }
   2156 
   2157 void cl::HideUnrelatedOptions(cl::OptionCategory &Category, SubCommand &Sub) {
   2158   for (auto &I : Sub.OptionsMap) {
   2159     if (I.second->Category != &Category &&
   2160         I.second->Category != &GenericCategory)
   2161       I.second->setHiddenFlag(cl::ReallyHidden);
   2162   }
   2163 }
   2164 
   2165 void cl::HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
   2166                               SubCommand &Sub) {
   2167   auto CategoriesBegin = Categories.begin();
   2168   auto CategoriesEnd = Categories.end();
   2169   for (auto &I : Sub.OptionsMap) {
   2170     if (std::find(CategoriesBegin, CategoriesEnd, I.second->Category) ==
   2171             CategoriesEnd &&
   2172         I.second->Category != &GenericCategory)
   2173       I.second->setHiddenFlag(cl::ReallyHidden);
   2174   }
   2175 }
   2176 
   2177 void cl::ResetCommandLineParser() { GlobalParser->reset(); }
   2178 void cl::ResetAllOptionOccurrences() {
   2179   GlobalParser->ResetAllOptionOccurrences();
   2180 }
   2181 
   2182 void LLVMParseCommandLineOptions(int argc, const char *const *argv,
   2183                                  const char *Overview) {
   2184   llvm::cl::ParseCommandLineOptions(argc, argv, StringRef(Overview), true);
   2185 }
   2186