xref: /llvm-project/llvm/lib/Support/CommandLine.cpp (revision 39c150eecbc1cf83836c59a516ee9aa1795a189c)
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/StringExtras.h"
28 #include "llvm/ADT/StringMap.h"
29 #include "llvm/ADT/Twine.h"
30 #include "llvm/Config/config.h"
31 #include "llvm/Support/ConvertUTF.h"
32 #include "llvm/Support/Debug.h"
33 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Support/FileSystem.h"
35 #include "llvm/Support/Host.h"
36 #include "llvm/Support/ManagedStatic.h"
37 #include "llvm/Support/MemoryBuffer.h"
38 #include "llvm/Support/Path.h"
39 #include "llvm/Support/Process.h"
40 #include "llvm/Support/StringSaver.h"
41 #include "llvm/Support/raw_ostream.h"
42 #include <cstdlib>
43 #include <map>
44 using namespace llvm;
45 using namespace cl;
46 
47 #define DEBUG_TYPE "commandline"
48 
49 //===----------------------------------------------------------------------===//
50 // Template instantiations and anchors.
51 //
52 namespace llvm {
53 namespace cl {
54 template class basic_parser<bool>;
55 template class basic_parser<boolOrDefault>;
56 template class basic_parser<int>;
57 template class basic_parser<unsigned>;
58 template class basic_parser<unsigned long long>;
59 template class basic_parser<double>;
60 template class basic_parser<float>;
61 template class basic_parser<std::string>;
62 template class basic_parser<char>;
63 
64 template class opt<unsigned>;
65 template class opt<int>;
66 template class opt<std::string>;
67 template class opt<char>;
68 template class opt<bool>;
69 }
70 } // end namespace llvm::cl
71 
72 // Pin the vtables to this file.
73 void GenericOptionValue::anchor() {}
74 void OptionValue<boolOrDefault>::anchor() {}
75 void OptionValue<std::string>::anchor() {}
76 void Option::anchor() {}
77 void basic_parser_impl::anchor() {}
78 void parser<bool>::anchor() {}
79 void parser<boolOrDefault>::anchor() {}
80 void parser<int>::anchor() {}
81 void parser<unsigned>::anchor() {}
82 void parser<unsigned long long>::anchor() {}
83 void parser<double>::anchor() {}
84 void parser<float>::anchor() {}
85 void parser<std::string>::anchor() {}
86 void parser<char>::anchor() {}
87 
88 //===----------------------------------------------------------------------===//
89 
90 namespace {
91 
92 class CommandLineParser {
93 public:
94   // Globals for name and overview of program.  Program name is not a string to
95   // avoid static ctor/dtor issues.
96   std::string ProgramName;
97   StringRef ProgramOverview;
98 
99   // This collects additional help to be printed.
100   std::vector<StringRef> MoreHelp;
101 
102   // This collects the different option categories that have been registered.
103   SmallPtrSet<OptionCategory *, 16> RegisteredOptionCategories;
104 
105   // This collects the different subcommands that have been registered.
106   SmallPtrSet<SubCommand *, 4> RegisteredSubCommands;
107 
108   CommandLineParser() : ActiveSubCommand(nullptr) {
109     registerSubCommand(&*TopLevelSubCommand);
110     registerSubCommand(&*AllSubCommands);
111   }
112 
113   void ResetAllOptionOccurrences();
114 
115   bool ParseCommandLineOptions(int argc, const char *const *argv,
116                                StringRef Overview, raw_ostream *Errs = nullptr);
117 
118   void addLiteralOption(Option &Opt, SubCommand *SC, StringRef Name) {
119     if (Opt.hasArgStr())
120       return;
121     if (!SC->OptionsMap.insert(std::make_pair(Name, &Opt)).second) {
122       errs() << ProgramName << ": CommandLine Error: Option '" << Name
123              << "' registered more than once!\n";
124       report_fatal_error("inconsistency in registered CommandLine options");
125     }
126 
127     // If we're adding this to all sub-commands, add it to the ones that have
128     // already been registered.
129     if (SC == &*AllSubCommands) {
130       for (const auto &Sub : RegisteredSubCommands) {
131         if (SC == Sub)
132           continue;
133         addLiteralOption(Opt, Sub, Name);
134       }
135     }
136   }
137 
138   void addLiteralOption(Option &Opt, StringRef Name) {
139     if (Opt.Subs.empty())
140       addLiteralOption(Opt, &*TopLevelSubCommand, Name);
141     else {
142       for (auto SC : Opt.Subs)
143         addLiteralOption(Opt, SC, Name);
144     }
145   }
146 
147   void addOption(Option *O, SubCommand *SC) {
148     bool HadErrors = false;
149     if (O->hasArgStr()) {
150       // Add argument to the argument map!
151       if (!SC->OptionsMap.insert(std::make_pair(O->ArgStr, O)).second) {
152         errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
153                << "' registered more than once!\n";
154         HadErrors = true;
155       }
156     }
157 
158     // Remember information about positional options.
159     if (O->getFormattingFlag() == cl::Positional)
160       SC->PositionalOpts.push_back(O);
161     else if (O->getMiscFlags() & cl::Sink) // Remember sink options
162       SC->SinkOpts.push_back(O);
163     else if (O->getNumOccurrencesFlag() == cl::ConsumeAfter) {
164       if (SC->ConsumeAfterOpt) {
165         O->error("Cannot specify more than one option with cl::ConsumeAfter!");
166         HadErrors = true;
167       }
168       SC->ConsumeAfterOpt = O;
169     }
170 
171     // Fail hard if there were errors. These are strictly unrecoverable and
172     // indicate serious issues such as conflicting option names or an
173     // incorrectly
174     // linked LLVM distribution.
175     if (HadErrors)
176       report_fatal_error("inconsistency in registered CommandLine options");
177 
178     // If we're adding this to all sub-commands, add it to the ones that have
179     // already been registered.
180     if (SC == &*AllSubCommands) {
181       for (const auto &Sub : RegisteredSubCommands) {
182         if (SC == Sub)
183           continue;
184         addOption(O, Sub);
185       }
186     }
187   }
188 
189   void addOption(Option *O) {
190     if (O->Subs.empty()) {
191       addOption(O, &*TopLevelSubCommand);
192     } else {
193       for (auto SC : O->Subs)
194         addOption(O, SC);
195     }
196   }
197 
198   void removeOption(Option *O, SubCommand *SC) {
199     SmallVector<StringRef, 16> OptionNames;
200     O->getExtraOptionNames(OptionNames);
201     if (O->hasArgStr())
202       OptionNames.push_back(O->ArgStr);
203 
204     SubCommand &Sub = *SC;
205     for (auto Name : OptionNames)
206       Sub.OptionsMap.erase(Name);
207 
208     if (O->getFormattingFlag() == cl::Positional)
209       for (auto Opt = Sub.PositionalOpts.begin();
210            Opt != Sub.PositionalOpts.end(); ++Opt) {
211         if (*Opt == O) {
212           Sub.PositionalOpts.erase(Opt);
213           break;
214         }
215       }
216     else if (O->getMiscFlags() & cl::Sink)
217       for (auto Opt = Sub.SinkOpts.begin(); Opt != Sub.SinkOpts.end(); ++Opt) {
218         if (*Opt == O) {
219           Sub.SinkOpts.erase(Opt);
220           break;
221         }
222       }
223     else if (O == Sub.ConsumeAfterOpt)
224       Sub.ConsumeAfterOpt = nullptr;
225   }
226 
227   void removeOption(Option *O) {
228     if (O->Subs.empty())
229       removeOption(O, &*TopLevelSubCommand);
230     else {
231       if (O->isInAllSubCommands()) {
232         for (auto SC : RegisteredSubCommands)
233           removeOption(O, SC);
234       } else {
235         for (auto SC : O->Subs)
236           removeOption(O, SC);
237       }
238     }
239   }
240 
241   bool hasOptions(const SubCommand &Sub) const {
242     return (!Sub.OptionsMap.empty() || !Sub.PositionalOpts.empty() ||
243             nullptr != Sub.ConsumeAfterOpt);
244   }
245 
246   bool hasOptions() const {
247     for (const auto &S : RegisteredSubCommands) {
248       if (hasOptions(*S))
249         return true;
250     }
251     return false;
252   }
253 
254   SubCommand *getActiveSubCommand() { return ActiveSubCommand; }
255 
256   void updateArgStr(Option *O, StringRef NewName, SubCommand *SC) {
257     SubCommand &Sub = *SC;
258     if (!Sub.OptionsMap.insert(std::make_pair(NewName, O)).second) {
259       errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
260              << "' registered more than once!\n";
261       report_fatal_error("inconsistency in registered CommandLine options");
262     }
263     Sub.OptionsMap.erase(O->ArgStr);
264   }
265 
266   void updateArgStr(Option *O, StringRef NewName) {
267     if (O->Subs.empty())
268       updateArgStr(O, NewName, &*TopLevelSubCommand);
269     else {
270       for (auto SC : O->Subs)
271         updateArgStr(O, NewName, SC);
272     }
273   }
274 
275   void printOptionValues();
276 
277   void registerCategory(OptionCategory *cat) {
278     assert(count_if(RegisteredOptionCategories,
279                     [cat](const OptionCategory *Category) {
280              return cat->getName() == Category->getName();
281            }) == 0 &&
282            "Duplicate option categories");
283 
284     RegisteredOptionCategories.insert(cat);
285   }
286 
287   void registerSubCommand(SubCommand *sub) {
288     assert(count_if(RegisteredSubCommands,
289                     [sub](const SubCommand *Sub) {
290                       return (!sub->getName().empty()) &&
291                              (Sub->getName() == sub->getName());
292                     }) == 0 &&
293            "Duplicate subcommands");
294     RegisteredSubCommands.insert(sub);
295 
296     // For all options that have been registered for all subcommands, add the
297     // option to this subcommand now.
298     if (sub != &*AllSubCommands) {
299       for (auto &E : AllSubCommands->OptionsMap) {
300         Option *O = E.second;
301         if ((O->isPositional() || O->isSink() || O->isConsumeAfter()) ||
302             O->hasArgStr())
303           addOption(O, sub);
304         else
305           addLiteralOption(*O, sub, E.first());
306       }
307     }
308   }
309 
310   void unregisterSubCommand(SubCommand *sub) {
311     RegisteredSubCommands.erase(sub);
312   }
313 
314   iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
315   getRegisteredSubcommands() {
316     return make_range(RegisteredSubCommands.begin(),
317                       RegisteredSubCommands.end());
318   }
319 
320   void reset() {
321     ActiveSubCommand = nullptr;
322     ProgramName.clear();
323     ProgramOverview = StringRef();
324 
325     MoreHelp.clear();
326     RegisteredOptionCategories.clear();
327 
328     ResetAllOptionOccurrences();
329     RegisteredSubCommands.clear();
330 
331     TopLevelSubCommand->reset();
332     AllSubCommands->reset();
333     registerSubCommand(&*TopLevelSubCommand);
334     registerSubCommand(&*AllSubCommands);
335   }
336 
337 private:
338   SubCommand *ActiveSubCommand;
339 
340   Option *LookupOption(SubCommand &Sub, StringRef &Arg, StringRef &Value);
341   SubCommand *LookupSubCommand(StringRef Name);
342 };
343 
344 } // namespace
345 
346 static ManagedStatic<CommandLineParser> GlobalParser;
347 
348 void cl::AddLiteralOption(Option &O, StringRef Name) {
349   GlobalParser->addLiteralOption(O, Name);
350 }
351 
352 extrahelp::extrahelp(StringRef Help) : morehelp(Help) {
353   GlobalParser->MoreHelp.push_back(Help);
354 }
355 
356 void Option::addArgument() {
357   GlobalParser->addOption(this);
358   FullyInitialized = true;
359 }
360 
361 void Option::removeArgument() { GlobalParser->removeOption(this); }
362 
363 void Option::setArgStr(StringRef S) {
364   if (FullyInitialized)
365     GlobalParser->updateArgStr(this, S);
366   assert((S.empty() || S[0] != '-') && "Option can't start with '-");
367   ArgStr = S;
368 }
369 
370 // Initialise the general option category.
371 OptionCategory llvm::cl::GeneralCategory("General options");
372 
373 void OptionCategory::registerCategory() {
374   GlobalParser->registerCategory(this);
375 }
376 
377 // A special subcommand representing no subcommand
378 ManagedStatic<SubCommand> llvm::cl::TopLevelSubCommand;
379 
380 // A special subcommand that can be used to put an option into all subcommands.
381 ManagedStatic<SubCommand> llvm::cl::AllSubCommands;
382 
383 void SubCommand::registerSubCommand() {
384   GlobalParser->registerSubCommand(this);
385 }
386 
387 void SubCommand::unregisterSubCommand() {
388   GlobalParser->unregisterSubCommand(this);
389 }
390 
391 void SubCommand::reset() {
392   PositionalOpts.clear();
393   SinkOpts.clear();
394   OptionsMap.clear();
395 
396   ConsumeAfterOpt = nullptr;
397 }
398 
399 SubCommand::operator bool() const {
400   return (GlobalParser->getActiveSubCommand() == this);
401 }
402 
403 //===----------------------------------------------------------------------===//
404 // Basic, shared command line option processing machinery.
405 //
406 
407 /// LookupOption - Lookup the option specified by the specified option on the
408 /// command line.  If there is a value specified (after an equal sign) return
409 /// that as well.  This assumes that leading dashes have already been stripped.
410 Option *CommandLineParser::LookupOption(SubCommand &Sub, StringRef &Arg,
411                                         StringRef &Value) {
412   // Reject all dashes.
413   if (Arg.empty())
414     return nullptr;
415   assert(&Sub != &*AllSubCommands);
416 
417   size_t EqualPos = Arg.find('=');
418 
419   // If we have an equals sign, remember the value.
420   if (EqualPos == StringRef::npos) {
421     // Look up the option.
422     auto I = Sub.OptionsMap.find(Arg);
423     if (I == Sub.OptionsMap.end())
424       return nullptr;
425 
426     return I != Sub.OptionsMap.end() ? I->second : nullptr;
427   }
428 
429   // If the argument before the = is a valid option name, we match.  If not,
430   // return Arg unmolested.
431   auto I = Sub.OptionsMap.find(Arg.substr(0, EqualPos));
432   if (I == Sub.OptionsMap.end())
433     return nullptr;
434 
435   Value = Arg.substr(EqualPos + 1);
436   Arg = Arg.substr(0, EqualPos);
437   return I->second;
438 }
439 
440 SubCommand *CommandLineParser::LookupSubCommand(StringRef Name) {
441   if (Name.empty())
442     return &*TopLevelSubCommand;
443   for (auto S : RegisteredSubCommands) {
444     if (S == &*AllSubCommands)
445       continue;
446     if (S->getName().empty())
447       continue;
448 
449     if (StringRef(S->getName()) == StringRef(Name))
450       return S;
451   }
452   return &*TopLevelSubCommand;
453 }
454 
455 /// LookupNearestOption - Lookup the closest match to the option specified by
456 /// the specified option on the command line.  If there is a value specified
457 /// (after an equal sign) return that as well.  This assumes that leading dashes
458 /// have already been stripped.
459 static Option *LookupNearestOption(StringRef Arg,
460                                    const StringMap<Option *> &OptionsMap,
461                                    std::string &NearestString) {
462   // Reject all dashes.
463   if (Arg.empty())
464     return nullptr;
465 
466   // Split on any equal sign.
467   std::pair<StringRef, StringRef> SplitArg = Arg.split('=');
468   StringRef &LHS = SplitArg.first; // LHS == Arg when no '=' is present.
469   StringRef &RHS = SplitArg.second;
470 
471   // Find the closest match.
472   Option *Best = nullptr;
473   unsigned BestDistance = 0;
474   for (StringMap<Option *>::const_iterator it = OptionsMap.begin(),
475                                            ie = OptionsMap.end();
476        it != ie; ++it) {
477     Option *O = it->second;
478     SmallVector<StringRef, 16> OptionNames;
479     O->getExtraOptionNames(OptionNames);
480     if (O->hasArgStr())
481       OptionNames.push_back(O->ArgStr);
482 
483     bool PermitValue = O->getValueExpectedFlag() != cl::ValueDisallowed;
484     StringRef Flag = PermitValue ? LHS : Arg;
485     for (auto Name : OptionNames) {
486       unsigned Distance = StringRef(Name).edit_distance(
487           Flag, /*AllowReplacements=*/true, /*MaxEditDistance=*/BestDistance);
488       if (!Best || Distance < BestDistance) {
489         Best = O;
490         BestDistance = Distance;
491         if (RHS.empty() || !PermitValue)
492           NearestString = Name;
493         else
494           NearestString = (Twine(Name) + "=" + RHS).str();
495       }
496     }
497   }
498 
499   return Best;
500 }
501 
502 /// CommaSeparateAndAddOccurrence - A wrapper around Handler->addOccurrence()
503 /// that does special handling of cl::CommaSeparated options.
504 static bool CommaSeparateAndAddOccurrence(Option *Handler, unsigned pos,
505                                           StringRef ArgName, StringRef Value,
506                                           bool MultiArg = false) {
507   // Check to see if this option accepts a comma separated list of values.  If
508   // it does, we have to split up the value into multiple values.
509   if (Handler->getMiscFlags() & CommaSeparated) {
510     StringRef Val(Value);
511     StringRef::size_type Pos = Val.find(',');
512 
513     while (Pos != StringRef::npos) {
514       // Process the portion before the comma.
515       if (Handler->addOccurrence(pos, ArgName, Val.substr(0, Pos), MultiArg))
516         return true;
517       // Erase the portion before the comma, AND the comma.
518       Val = Val.substr(Pos + 1);
519       // Check for another comma.
520       Pos = Val.find(',');
521     }
522 
523     Value = Val;
524   }
525 
526   return Handler->addOccurrence(pos, ArgName, Value, MultiArg);
527 }
528 
529 /// ProvideOption - For Value, this differentiates between an empty value ("")
530 /// and a null value (StringRef()).  The later is accepted for arguments that
531 /// don't allow a value (-foo) the former is rejected (-foo=).
532 static inline bool ProvideOption(Option *Handler, StringRef ArgName,
533                                  StringRef Value, int argc,
534                                  const char *const *argv, int &i) {
535   // Is this a multi-argument option?
536   unsigned NumAdditionalVals = Handler->getNumAdditionalVals();
537 
538   // Enforce value requirements
539   switch (Handler->getValueExpectedFlag()) {
540   case ValueRequired:
541     if (!Value.data()) { // No value specified?
542       if (i + 1 >= argc)
543         return Handler->error("requires a value!");
544       // Steal the next argument, like for '-o filename'
545       assert(argv && "null check");
546       Value = StringRef(argv[++i]);
547     }
548     break;
549   case ValueDisallowed:
550     if (NumAdditionalVals > 0)
551       return Handler->error("multi-valued option specified"
552                             " with ValueDisallowed modifier!");
553 
554     if (Value.data())
555       return Handler->error("does not allow a value! '" + Twine(Value) +
556                             "' specified.");
557     break;
558   case ValueOptional:
559     break;
560   }
561 
562   // If this isn't a multi-arg option, just run the handler.
563   if (NumAdditionalVals == 0)
564     return CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value);
565 
566   // If it is, run the handle several times.
567   bool MultiArg = false;
568 
569   if (Value.data()) {
570     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
571       return true;
572     --NumAdditionalVals;
573     MultiArg = true;
574   }
575 
576   while (NumAdditionalVals > 0) {
577     if (i + 1 >= argc)
578       return Handler->error("not enough values!");
579     assert(argv && "null check");
580     Value = StringRef(argv[++i]);
581 
582     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
583       return true;
584     MultiArg = true;
585     --NumAdditionalVals;
586   }
587   return false;
588 }
589 
590 static bool ProvidePositionalOption(Option *Handler, StringRef Arg, int i) {
591   int Dummy = i;
592   return ProvideOption(Handler, Handler->ArgStr, Arg, 0, nullptr, Dummy);
593 }
594 
595 // Option predicates...
596 static inline bool isGrouping(const Option *O) {
597   return O->getFormattingFlag() == cl::Grouping;
598 }
599 static inline bool isPrefixedOrGrouping(const Option *O) {
600   return isGrouping(O) || O->getFormattingFlag() == cl::Prefix;
601 }
602 
603 // getOptionPred - Check to see if there are any options that satisfy the
604 // specified predicate with names that are the prefixes in Name.  This is
605 // checked by progressively stripping characters off of the name, checking to
606 // see if there options that satisfy the predicate.  If we find one, return it,
607 // otherwise return null.
608 //
609 static Option *getOptionPred(StringRef Name, size_t &Length,
610                              bool (*Pred)(const Option *),
611                              const StringMap<Option *> &OptionsMap) {
612 
613   StringMap<Option *>::const_iterator OMI = OptionsMap.find(Name);
614 
615   // Loop while we haven't found an option and Name still has at least two
616   // characters in it (so that the next iteration will not be the empty
617   // string.
618   while (OMI == OptionsMap.end() && Name.size() > 1) {
619     Name = Name.substr(0, Name.size() - 1); // Chop off the last character.
620     OMI = OptionsMap.find(Name);
621   }
622 
623   if (OMI != OptionsMap.end() && Pred(OMI->second)) {
624     Length = Name.size();
625     return OMI->second; // Found one!
626   }
627   return nullptr; // No option found!
628 }
629 
630 /// HandlePrefixedOrGroupedOption - The specified argument string (which started
631 /// with at least one '-') does not fully match an available option.  Check to
632 /// see if this is a prefix or grouped option.  If so, split arg into output an
633 /// Arg/Value pair and return the Option to parse it with.
634 static Option *
635 HandlePrefixedOrGroupedOption(StringRef &Arg, StringRef &Value,
636                               bool &ErrorParsing,
637                               const StringMap<Option *> &OptionsMap) {
638   if (Arg.size() == 1)
639     return nullptr;
640 
641   // Do the lookup!
642   size_t Length = 0;
643   Option *PGOpt = getOptionPred(Arg, Length, isPrefixedOrGrouping, OptionsMap);
644   if (!PGOpt)
645     return nullptr;
646 
647   // If the option is a prefixed option, then the value is simply the
648   // rest of the name...  so fall through to later processing, by
649   // setting up the argument name flags and value fields.
650   if (PGOpt->getFormattingFlag() == cl::Prefix) {
651     Value = Arg.substr(Length);
652     Arg = Arg.substr(0, Length);
653     assert(OptionsMap.count(Arg) && OptionsMap.find(Arg)->second == PGOpt);
654     return PGOpt;
655   }
656 
657   // This must be a grouped option... handle them now.  Grouping options can't
658   // have values.
659   assert(isGrouping(PGOpt) && "Broken getOptionPred!");
660 
661   do {
662     // Move current arg name out of Arg into OneArgName.
663     StringRef OneArgName = Arg.substr(0, Length);
664     Arg = Arg.substr(Length);
665 
666     // Because ValueRequired is an invalid flag for grouped arguments,
667     // we don't need to pass argc/argv in.
668     assert(PGOpt->getValueExpectedFlag() != cl::ValueRequired &&
669            "Option can not be cl::Grouping AND cl::ValueRequired!");
670     int Dummy = 0;
671     ErrorParsing |=
672         ProvideOption(PGOpt, OneArgName, StringRef(), 0, nullptr, Dummy);
673 
674     // Get the next grouping option.
675     PGOpt = getOptionPred(Arg, Length, isGrouping, OptionsMap);
676   } while (PGOpt && Length != Arg.size());
677 
678   // Return the last option with Arg cut down to just the last one.
679   return PGOpt;
680 }
681 
682 static bool RequiresValue(const Option *O) {
683   return O->getNumOccurrencesFlag() == cl::Required ||
684          O->getNumOccurrencesFlag() == cl::OneOrMore;
685 }
686 
687 static bool EatsUnboundedNumberOfValues(const Option *O) {
688   return O->getNumOccurrencesFlag() == cl::ZeroOrMore ||
689          O->getNumOccurrencesFlag() == cl::OneOrMore;
690 }
691 
692 static bool isWhitespace(char C) { return strchr(" \t\n\r\f\v", C); }
693 
694 static bool isQuote(char C) { return C == '\"' || C == '\''; }
695 
696 void cl::TokenizeGNUCommandLine(StringRef Src, StringSaver &Saver,
697                                 SmallVectorImpl<const char *> &NewArgv,
698                                 bool MarkEOLs) {
699   SmallString<128> Token;
700   for (size_t I = 0, E = Src.size(); I != E; ++I) {
701     // Consume runs of whitespace.
702     if (Token.empty()) {
703       while (I != E && isWhitespace(Src[I])) {
704         // Mark the end of lines in response files
705         if (MarkEOLs && Src[I] == '\n')
706           NewArgv.push_back(nullptr);
707         ++I;
708       }
709       if (I == E)
710         break;
711     }
712 
713     // Backslash escapes the next character.
714     if (I + 1 < E && Src[I] == '\\') {
715       ++I; // Skip the escape.
716       Token.push_back(Src[I]);
717       continue;
718     }
719 
720     // Consume a quoted string.
721     if (isQuote(Src[I])) {
722       char Quote = Src[I++];
723       while (I != E && Src[I] != Quote) {
724         // Backslash escapes the next character.
725         if (Src[I] == '\\' && I + 1 != E)
726           ++I;
727         Token.push_back(Src[I]);
728         ++I;
729       }
730       if (I == E)
731         break;
732       continue;
733     }
734 
735     // End the token if this is whitespace.
736     if (isWhitespace(Src[I])) {
737       if (!Token.empty())
738         NewArgv.push_back(Saver.save(StringRef(Token)).data());
739       Token.clear();
740       continue;
741     }
742 
743     // This is a normal character.  Append it.
744     Token.push_back(Src[I]);
745   }
746 
747   // Append the last token after hitting EOF with no whitespace.
748   if (!Token.empty())
749     NewArgv.push_back(Saver.save(StringRef(Token)).data());
750   // Mark the end of response files
751   if (MarkEOLs)
752     NewArgv.push_back(nullptr);
753 }
754 
755 /// Backslashes are interpreted in a rather complicated way in the Windows-style
756 /// command line, because backslashes are used both to separate path and to
757 /// escape double quote. This method consumes runs of backslashes as well as the
758 /// following double quote if it's escaped.
759 ///
760 ///  * If an even number of backslashes is followed by a double quote, one
761 ///    backslash is output for every pair of backslashes, and the last double
762 ///    quote remains unconsumed. The double quote will later be interpreted as
763 ///    the start or end of a quoted string in the main loop outside of this
764 ///    function.
765 ///
766 ///  * If an odd number of backslashes is followed by a double quote, one
767 ///    backslash is output for every pair of backslashes, and a double quote is
768 ///    output for the last pair of backslash-double quote. The double quote is
769 ///    consumed in this case.
770 ///
771 ///  * Otherwise, backslashes are interpreted literally.
772 static size_t parseBackslash(StringRef Src, size_t I, SmallString<128> &Token) {
773   size_t E = Src.size();
774   int BackslashCount = 0;
775   // Skip the backslashes.
776   do {
777     ++I;
778     ++BackslashCount;
779   } while (I != E && Src[I] == '\\');
780 
781   bool FollowedByDoubleQuote = (I != E && Src[I] == '"');
782   if (FollowedByDoubleQuote) {
783     Token.append(BackslashCount / 2, '\\');
784     if (BackslashCount % 2 == 0)
785       return I - 1;
786     Token.push_back('"');
787     return I;
788   }
789   Token.append(BackslashCount, '\\');
790   return I - 1;
791 }
792 
793 void cl::TokenizeWindowsCommandLine(StringRef Src, StringSaver &Saver,
794                                     SmallVectorImpl<const char *> &NewArgv,
795                                     bool MarkEOLs) {
796   SmallString<128> Token;
797 
798   // This is a small state machine to consume characters until it reaches the
799   // end of the source string.
800   enum { INIT, UNQUOTED, QUOTED } State = INIT;
801   for (size_t I = 0, E = Src.size(); I != E; ++I) {
802     // INIT state indicates that the current input index is at the start of
803     // the string or between tokens.
804     if (State == INIT) {
805       if (isWhitespace(Src[I])) {
806         // Mark the end of lines in response files
807         if (MarkEOLs && Src[I] == '\n')
808           NewArgv.push_back(nullptr);
809         continue;
810       }
811       if (Src[I] == '"') {
812         State = QUOTED;
813         continue;
814       }
815       if (Src[I] == '\\') {
816         I = parseBackslash(Src, I, Token);
817         State = UNQUOTED;
818         continue;
819       }
820       Token.push_back(Src[I]);
821       State = UNQUOTED;
822       continue;
823     }
824 
825     // UNQUOTED state means that it's reading a token not quoted by double
826     // quotes.
827     if (State == UNQUOTED) {
828       // Whitespace means the end of the token.
829       if (isWhitespace(Src[I])) {
830         NewArgv.push_back(Saver.save(StringRef(Token)).data());
831         Token.clear();
832         State = INIT;
833         // Mark the end of lines in response files
834         if (MarkEOLs && Src[I] == '\n')
835           NewArgv.push_back(nullptr);
836         continue;
837       }
838       if (Src[I] == '"') {
839         State = QUOTED;
840         continue;
841       }
842       if (Src[I] == '\\') {
843         I = parseBackslash(Src, I, Token);
844         continue;
845       }
846       Token.push_back(Src[I]);
847       continue;
848     }
849 
850     // QUOTED state means that it's reading a token quoted by double quotes.
851     if (State == QUOTED) {
852       if (Src[I] == '"') {
853         State = UNQUOTED;
854         continue;
855       }
856       if (Src[I] == '\\') {
857         I = parseBackslash(Src, I, Token);
858         continue;
859       }
860       Token.push_back(Src[I]);
861     }
862   }
863   // Append the last token after hitting EOF with no whitespace.
864   if (!Token.empty())
865     NewArgv.push_back(Saver.save(StringRef(Token)).data());
866   // Mark the end of response files
867   if (MarkEOLs)
868     NewArgv.push_back(nullptr);
869 }
870 
871 // It is called byte order marker but the UTF-8 BOM is actually not affected
872 // by the host system's endianness.
873 static bool hasUTF8ByteOrderMark(ArrayRef<char> S) {
874   return (S.size() >= 3 && S[0] == '\xef' && S[1] == '\xbb' && S[2] == '\xbf');
875 }
876 
877 static bool ExpandResponseFile(StringRef FName, StringSaver &Saver,
878                                TokenizerCallback Tokenizer,
879                                SmallVectorImpl<const char *> &NewArgv,
880                                bool MarkEOLs, bool RelativeNames) {
881   ErrorOr<std::unique_ptr<MemoryBuffer>> MemBufOrErr =
882       MemoryBuffer::getFile(FName);
883   if (!MemBufOrErr)
884     return false;
885   MemoryBuffer &MemBuf = *MemBufOrErr.get();
886   StringRef Str(MemBuf.getBufferStart(), MemBuf.getBufferSize());
887 
888   // If we have a UTF-16 byte order mark, convert to UTF-8 for parsing.
889   ArrayRef<char> BufRef(MemBuf.getBufferStart(), MemBuf.getBufferEnd());
890   std::string UTF8Buf;
891   if (hasUTF16ByteOrderMark(BufRef)) {
892     if (!convertUTF16ToUTF8String(BufRef, UTF8Buf))
893       return false;
894     Str = StringRef(UTF8Buf);
895   }
896   // If we see UTF-8 BOM sequence at the beginning of a file, we shall remove
897   // these bytes before parsing.
898   // Reference: http://en.wikipedia.org/wiki/UTF-8#Byte_order_mark
899   else if (hasUTF8ByteOrderMark(BufRef))
900     Str = StringRef(BufRef.data() + 3, BufRef.size() - 3);
901 
902   // Tokenize the contents into NewArgv.
903   Tokenizer(Str, Saver, NewArgv, MarkEOLs);
904 
905   // If names of nested response files should be resolved relative to including
906   // file, replace the included response file names with their full paths
907   // obtained by required resolution.
908   if (RelativeNames)
909     for (unsigned I = 0; I < NewArgv.size(); ++I)
910       if (NewArgv[I]) {
911         StringRef Arg = NewArgv[I];
912         if (Arg.front() == '@') {
913           StringRef FileName = Arg.drop_front();
914           if (llvm::sys::path::is_relative(FileName)) {
915             SmallString<128> ResponseFile;
916             ResponseFile.append(1, '@');
917             if (llvm::sys::path::is_relative(FName)) {
918               SmallString<128> curr_dir;
919               llvm::sys::fs::current_path(curr_dir);
920               ResponseFile.append(curr_dir.str());
921             }
922             llvm::sys::path::append(
923                 ResponseFile, llvm::sys::path::parent_path(FName), FileName);
924             NewArgv[I] = Saver.save(ResponseFile.c_str()).data();
925           }
926         }
927       }
928 
929   return true;
930 }
931 
932 /// \brief Expand response files on a command line recursively using the given
933 /// StringSaver and tokenization strategy.
934 bool cl::ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
935                              SmallVectorImpl<const char *> &Argv,
936                              bool MarkEOLs, bool RelativeNames) {
937   unsigned RspFiles = 0;
938   bool AllExpanded = true;
939 
940   // Don't cache Argv.size() because it can change.
941   for (unsigned I = 0; I != Argv.size();) {
942     const char *Arg = Argv[I];
943     // Check if it is an EOL marker
944     if (Arg == nullptr) {
945       ++I;
946       continue;
947     }
948     if (Arg[0] != '@') {
949       ++I;
950       continue;
951     }
952 
953     // If we have too many response files, leave some unexpanded.  This avoids
954     // crashing on self-referential response files.
955     if (RspFiles++ > 20)
956       return false;
957 
958     // Replace this response file argument with the tokenization of its
959     // contents.  Nested response files are expanded in subsequent iterations.
960     SmallVector<const char *, 0> ExpandedArgv;
961     if (!ExpandResponseFile(Arg + 1, Saver, Tokenizer, ExpandedArgv,
962                             MarkEOLs, RelativeNames)) {
963       // We couldn't read this file, so we leave it in the argument stream and
964       // move on.
965       AllExpanded = false;
966       ++I;
967       continue;
968     }
969     Argv.erase(Argv.begin() + I);
970     Argv.insert(Argv.begin() + I, ExpandedArgv.begin(), ExpandedArgv.end());
971   }
972   return AllExpanded;
973 }
974 
975 /// ParseEnvironmentOptions - An alternative entry point to the
976 /// CommandLine library, which allows you to read the program's name
977 /// from the caller (as PROGNAME) and its command-line arguments from
978 /// an environment variable (whose name is given in ENVVAR).
979 ///
980 void cl::ParseEnvironmentOptions(const char *progName, const char *envVar,
981                                  const char *Overview) {
982   // Check args.
983   assert(progName && "Program name not specified");
984   assert(envVar && "Environment variable name missing");
985 
986   // Get the environment variable they want us to parse options out of.
987   llvm::Optional<std::string> envValue = sys::Process::GetEnv(StringRef(envVar));
988   if (!envValue)
989     return;
990 
991   // Get program's "name", which we wouldn't know without the caller
992   // telling us.
993   SmallVector<const char *, 20> newArgv;
994   BumpPtrAllocator A;
995   StringSaver Saver(A);
996   newArgv.push_back(Saver.save(progName).data());
997 
998   // Parse the value of the environment variable into a "command line"
999   // and hand it off to ParseCommandLineOptions().
1000   TokenizeGNUCommandLine(*envValue, Saver, newArgv);
1001   int newArgc = static_cast<int>(newArgv.size());
1002   ParseCommandLineOptions(newArgc, &newArgv[0], StringRef(Overview));
1003 }
1004 
1005 bool cl::ParseCommandLineOptions(int argc, const char *const *argv,
1006                                  StringRef Overview, raw_ostream *Errs) {
1007   return GlobalParser->ParseCommandLineOptions(argc, argv, Overview,
1008                                                Errs);
1009 }
1010 
1011 void CommandLineParser::ResetAllOptionOccurrences() {
1012   // So that we can parse different command lines multiple times in succession
1013   // we reset all option values to look like they have never been seen before.
1014   for (auto SC : RegisteredSubCommands) {
1015     for (auto &O : SC->OptionsMap)
1016       O.second->reset();
1017   }
1018 }
1019 
1020 bool CommandLineParser::ParseCommandLineOptions(int argc,
1021                                                 const char *const *argv,
1022                                                 StringRef Overview,
1023                                                 raw_ostream *Errs) {
1024   assert(hasOptions() && "No options specified!");
1025 
1026   // Expand response files.
1027   SmallVector<const char *, 20> newArgv(argv, argv + argc);
1028   BumpPtrAllocator A;
1029   StringSaver Saver(A);
1030   ExpandResponseFiles(Saver, TokenizeGNUCommandLine, newArgv);
1031   argv = &newArgv[0];
1032   argc = static_cast<int>(newArgv.size());
1033 
1034   // Copy the program name into ProgName, making sure not to overflow it.
1035   ProgramName = sys::path::filename(StringRef(argv[0]));
1036 
1037   ProgramOverview = Overview;
1038   bool IgnoreErrors = Errs;
1039   if (!Errs)
1040     Errs = &errs();
1041   bool ErrorParsing = false;
1042 
1043   // Check out the positional arguments to collect information about them.
1044   unsigned NumPositionalRequired = 0;
1045 
1046   // Determine whether or not there are an unlimited number of positionals
1047   bool HasUnlimitedPositionals = false;
1048 
1049   int FirstArg = 1;
1050   SubCommand *ChosenSubCommand = &*TopLevelSubCommand;
1051   if (argc >= 2 && argv[FirstArg][0] != '-') {
1052     // If the first argument specifies a valid subcommand, start processing
1053     // options from the second argument.
1054     ChosenSubCommand = LookupSubCommand(StringRef(argv[FirstArg]));
1055     if (ChosenSubCommand != &*TopLevelSubCommand)
1056       FirstArg = 2;
1057   }
1058   GlobalParser->ActiveSubCommand = ChosenSubCommand;
1059 
1060   assert(ChosenSubCommand);
1061   auto &ConsumeAfterOpt = ChosenSubCommand->ConsumeAfterOpt;
1062   auto &PositionalOpts = ChosenSubCommand->PositionalOpts;
1063   auto &SinkOpts = ChosenSubCommand->SinkOpts;
1064   auto &OptionsMap = ChosenSubCommand->OptionsMap;
1065 
1066   if (ConsumeAfterOpt) {
1067     assert(PositionalOpts.size() > 0 &&
1068            "Cannot specify cl::ConsumeAfter without a positional argument!");
1069   }
1070   if (!PositionalOpts.empty()) {
1071 
1072     // Calculate how many positional values are _required_.
1073     bool UnboundedFound = false;
1074     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
1075       Option *Opt = PositionalOpts[i];
1076       if (RequiresValue(Opt))
1077         ++NumPositionalRequired;
1078       else if (ConsumeAfterOpt) {
1079         // ConsumeAfter cannot be combined with "optional" positional options
1080         // unless there is only one positional argument...
1081         if (PositionalOpts.size() > 1) {
1082           if (!IgnoreErrors)
1083             Opt->error("error - this positional option will never be matched, "
1084                        "because it does not Require a value, and a "
1085                        "cl::ConsumeAfter option is active!");
1086           ErrorParsing = true;
1087         }
1088       } else if (UnboundedFound && !Opt->hasArgStr()) {
1089         // This option does not "require" a value...  Make sure this option is
1090         // not specified after an option that eats all extra arguments, or this
1091         // one will never get any!
1092         //
1093         if (!IgnoreErrors)
1094           Opt->error("error - option can never match, because "
1095                      "another positional argument will match an "
1096                      "unbounded number of values, and this option"
1097                      " does not require a value!");
1098         *Errs << ProgramName << ": CommandLine Error: Option '" << Opt->ArgStr
1099               << "' is all messed up!\n";
1100         *Errs << PositionalOpts.size();
1101         ErrorParsing = true;
1102       }
1103       UnboundedFound |= EatsUnboundedNumberOfValues(Opt);
1104     }
1105     HasUnlimitedPositionals = UnboundedFound || ConsumeAfterOpt;
1106   }
1107 
1108   // PositionalVals - A vector of "positional" arguments we accumulate into
1109   // the process at the end.
1110   //
1111   SmallVector<std::pair<StringRef, unsigned>, 4> PositionalVals;
1112 
1113   // If the program has named positional arguments, and the name has been run
1114   // across, keep track of which positional argument was named.  Otherwise put
1115   // the positional args into the PositionalVals list...
1116   Option *ActivePositionalArg = nullptr;
1117 
1118   // Loop over all of the arguments... processing them.
1119   bool DashDashFound = false; // Have we read '--'?
1120   for (int i = FirstArg; i < argc; ++i) {
1121     Option *Handler = nullptr;
1122     Option *NearestHandler = nullptr;
1123     std::string NearestHandlerString;
1124     StringRef Value;
1125     StringRef ArgName = "";
1126 
1127     // Check to see if this is a positional argument.  This argument is
1128     // considered to be positional if it doesn't start with '-', if it is "-"
1129     // itself, or if we have seen "--" already.
1130     //
1131     if (argv[i][0] != '-' || argv[i][1] == 0 || DashDashFound) {
1132       // Positional argument!
1133       if (ActivePositionalArg) {
1134         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1135         continue; // We are done!
1136       }
1137 
1138       if (!PositionalOpts.empty()) {
1139         PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1140 
1141         // All of the positional arguments have been fulfulled, give the rest to
1142         // the consume after option... if it's specified...
1143         //
1144         if (PositionalVals.size() >= NumPositionalRequired && ConsumeAfterOpt) {
1145           for (++i; i < argc; ++i)
1146             PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1147           break; // Handle outside of the argument processing loop...
1148         }
1149 
1150         // Delay processing positional arguments until the end...
1151         continue;
1152       }
1153     } else if (argv[i][0] == '-' && argv[i][1] == '-' && argv[i][2] == 0 &&
1154                !DashDashFound) {
1155       DashDashFound = true; // This is the mythical "--"?
1156       continue;             // Don't try to process it as an argument itself.
1157     } else if (ActivePositionalArg &&
1158                (ActivePositionalArg->getMiscFlags() & PositionalEatsArgs)) {
1159       // If there is a positional argument eating options, check to see if this
1160       // option is another positional argument.  If so, treat it as an argument,
1161       // otherwise feed it to the eating positional.
1162       ArgName = StringRef(argv[i] + 1);
1163       // Eat leading dashes.
1164       while (!ArgName.empty() && ArgName[0] == '-')
1165         ArgName = ArgName.substr(1);
1166 
1167       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
1168       if (!Handler || Handler->getFormattingFlag() != cl::Positional) {
1169         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1170         continue; // We are done!
1171       }
1172 
1173     } else { // We start with a '-', must be an argument.
1174       ArgName = StringRef(argv[i] + 1);
1175       // Eat leading dashes.
1176       while (!ArgName.empty() && ArgName[0] == '-')
1177         ArgName = ArgName.substr(1);
1178 
1179       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
1180 
1181       // Check to see if this "option" is really a prefixed or grouped argument.
1182       if (!Handler)
1183         Handler = HandlePrefixedOrGroupedOption(ArgName, Value, ErrorParsing,
1184                                                 OptionsMap);
1185 
1186       // Otherwise, look for the closest available option to report to the user
1187       // in the upcoming error.
1188       if (!Handler && SinkOpts.empty())
1189         NearestHandler =
1190             LookupNearestOption(ArgName, OptionsMap, NearestHandlerString);
1191     }
1192 
1193     if (!Handler) {
1194       if (SinkOpts.empty()) {
1195         *Errs << ProgramName << ": Unknown command line argument '" << argv[i]
1196               << "'.  Try: '" << argv[0] << " -help'\n";
1197 
1198         if (NearestHandler) {
1199           // If we know a near match, report it as well.
1200           *Errs << ProgramName << ": Did you mean '-" << NearestHandlerString
1201                  << "'?\n";
1202         }
1203 
1204         ErrorParsing = true;
1205       } else {
1206         for (SmallVectorImpl<Option *>::iterator I = SinkOpts.begin(),
1207                                                  E = SinkOpts.end();
1208              I != E; ++I)
1209           (*I)->addOccurrence(i, "", StringRef(argv[i]));
1210       }
1211       continue;
1212     }
1213 
1214     // If this is a named positional argument, just remember that it is the
1215     // active one...
1216     if (Handler->getFormattingFlag() == cl::Positional)
1217       ActivePositionalArg = Handler;
1218     else
1219       ErrorParsing |= ProvideOption(Handler, ArgName, Value, argc, argv, i);
1220   }
1221 
1222   // Check and handle positional arguments now...
1223   if (NumPositionalRequired > PositionalVals.size()) {
1224       *Errs << ProgramName
1225              << ": Not enough positional command line arguments specified!\n"
1226              << "Must specify at least " << NumPositionalRequired
1227              << " positional argument" << (NumPositionalRequired > 1 ? "s" : "")
1228              << ": See: " << argv[0] << " -help\n";
1229 
1230     ErrorParsing = true;
1231   } else if (!HasUnlimitedPositionals &&
1232              PositionalVals.size() > PositionalOpts.size()) {
1233     *Errs << ProgramName << ": Too many positional arguments specified!\n"
1234           << "Can specify at most " << PositionalOpts.size()
1235           << " positional arguments: See: " << argv[0] << " -help\n";
1236     ErrorParsing = true;
1237 
1238   } else if (!ConsumeAfterOpt) {
1239     // Positional args have already been handled if ConsumeAfter is specified.
1240     unsigned ValNo = 0, NumVals = static_cast<unsigned>(PositionalVals.size());
1241     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
1242       if (RequiresValue(PositionalOpts[i])) {
1243         ProvidePositionalOption(PositionalOpts[i], PositionalVals[ValNo].first,
1244                                 PositionalVals[ValNo].second);
1245         ValNo++;
1246         --NumPositionalRequired; // We fulfilled our duty...
1247       }
1248 
1249       // If we _can_ give this option more arguments, do so now, as long as we
1250       // do not give it values that others need.  'Done' controls whether the
1251       // option even _WANTS_ any more.
1252       //
1253       bool Done = PositionalOpts[i]->getNumOccurrencesFlag() == cl::Required;
1254       while (NumVals - ValNo > NumPositionalRequired && !Done) {
1255         switch (PositionalOpts[i]->getNumOccurrencesFlag()) {
1256         case cl::Optional:
1257           Done = true; // Optional arguments want _at most_ one value
1258           LLVM_FALLTHROUGH;
1259         case cl::ZeroOrMore: // Zero or more will take all they can get...
1260         case cl::OneOrMore:  // One or more will take all they can get...
1261           ProvidePositionalOption(PositionalOpts[i],
1262                                   PositionalVals[ValNo].first,
1263                                   PositionalVals[ValNo].second);
1264           ValNo++;
1265           break;
1266         default:
1267           llvm_unreachable("Internal error, unexpected NumOccurrences flag in "
1268                            "positional argument processing!");
1269         }
1270       }
1271     }
1272   } else {
1273     assert(ConsumeAfterOpt && NumPositionalRequired <= PositionalVals.size());
1274     unsigned ValNo = 0;
1275     for (size_t j = 1, e = PositionalOpts.size(); j != e; ++j)
1276       if (RequiresValue(PositionalOpts[j])) {
1277         ErrorParsing |= ProvidePositionalOption(PositionalOpts[j],
1278                                                 PositionalVals[ValNo].first,
1279                                                 PositionalVals[ValNo].second);
1280         ValNo++;
1281       }
1282 
1283     // Handle the case where there is just one positional option, and it's
1284     // optional.  In this case, we want to give JUST THE FIRST option to the
1285     // positional option and keep the rest for the consume after.  The above
1286     // loop would have assigned no values to positional options in this case.
1287     //
1288     if (PositionalOpts.size() == 1 && ValNo == 0 && !PositionalVals.empty()) {
1289       ErrorParsing |= ProvidePositionalOption(PositionalOpts[0],
1290                                               PositionalVals[ValNo].first,
1291                                               PositionalVals[ValNo].second);
1292       ValNo++;
1293     }
1294 
1295     // Handle over all of the rest of the arguments to the
1296     // cl::ConsumeAfter command line option...
1297     for (; ValNo != PositionalVals.size(); ++ValNo)
1298       ErrorParsing |=
1299           ProvidePositionalOption(ConsumeAfterOpt, PositionalVals[ValNo].first,
1300                                   PositionalVals[ValNo].second);
1301   }
1302 
1303   // Loop over args and make sure all required args are specified!
1304   for (const auto &Opt : OptionsMap) {
1305     switch (Opt.second->getNumOccurrencesFlag()) {
1306     case Required:
1307     case OneOrMore:
1308       if (Opt.second->getNumOccurrences() == 0) {
1309         Opt.second->error("must be specified at least once!");
1310         ErrorParsing = true;
1311       }
1312       LLVM_FALLTHROUGH;
1313     default:
1314       break;
1315     }
1316   }
1317 
1318   // Now that we know if -debug is specified, we can use it.
1319   // Note that if ReadResponseFiles == true, this must be done before the
1320   // memory allocated for the expanded command line is free()d below.
1321   DEBUG(dbgs() << "Args: ";
1322         for (int i = 0; i < argc; ++i) dbgs() << argv[i] << ' ';
1323         dbgs() << '\n';);
1324 
1325   // Free all of the memory allocated to the map.  Command line options may only
1326   // be processed once!
1327   MoreHelp.clear();
1328 
1329   // If we had an error processing our arguments, don't let the program execute
1330   if (ErrorParsing) {
1331     if (!IgnoreErrors)
1332       exit(1);
1333     return false;
1334   }
1335   return true;
1336 }
1337 
1338 //===----------------------------------------------------------------------===//
1339 // Option Base class implementation
1340 //
1341 
1342 bool Option::error(const Twine &Message, StringRef ArgName) {
1343   if (!ArgName.data())
1344     ArgName = ArgStr;
1345   if (ArgName.empty())
1346     errs() << HelpStr; // Be nice for positional arguments
1347   else
1348     errs() << GlobalParser->ProgramName << ": for the -" << ArgName;
1349 
1350   errs() << " option: " << Message << "\n";
1351   return true;
1352 }
1353 
1354 bool Option::addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
1355                            bool MultiArg) {
1356   if (!MultiArg)
1357     NumOccurrences++; // Increment the number of times we have been seen
1358 
1359   switch (getNumOccurrencesFlag()) {
1360   case Optional:
1361     if (NumOccurrences > 1)
1362       return error("may only occur zero or one times!", ArgName);
1363     break;
1364   case Required:
1365     if (NumOccurrences > 1)
1366       return error("must occur exactly one time!", ArgName);
1367     LLVM_FALLTHROUGH;
1368   case OneOrMore:
1369   case ZeroOrMore:
1370   case ConsumeAfter:
1371     break;
1372   }
1373 
1374   return handleOccurrence(pos, ArgName, Value);
1375 }
1376 
1377 // getValueStr - Get the value description string, using "DefaultMsg" if nothing
1378 // has been specified yet.
1379 //
1380 static StringRef getValueStr(const Option &O, StringRef DefaultMsg) {
1381   if (O.ValueStr.empty())
1382     return DefaultMsg;
1383   return O.ValueStr;
1384 }
1385 
1386 //===----------------------------------------------------------------------===//
1387 // cl::alias class implementation
1388 //
1389 
1390 // Return the width of the option tag for printing...
1391 size_t alias::getOptionWidth() const { return ArgStr.size() + 6; }
1392 
1393 void Option::printHelpStr(StringRef HelpStr, size_t Indent,
1394                                  size_t FirstLineIndentedBy) {
1395   std::pair<StringRef, StringRef> Split = HelpStr.split('\n');
1396   outs().indent(Indent - FirstLineIndentedBy) << " - " << Split.first << "\n";
1397   while (!Split.second.empty()) {
1398     Split = Split.second.split('\n');
1399     outs().indent(Indent) << Split.first << "\n";
1400   }
1401 }
1402 
1403 // Print out the option for the alias.
1404 void alias::printOptionInfo(size_t GlobalWidth) const {
1405   outs() << "  -" << ArgStr;
1406   printHelpStr(HelpStr, GlobalWidth, ArgStr.size() + 6);
1407 }
1408 
1409 //===----------------------------------------------------------------------===//
1410 // Parser Implementation code...
1411 //
1412 
1413 // basic_parser implementation
1414 //
1415 
1416 // Return the width of the option tag for printing...
1417 size_t basic_parser_impl::getOptionWidth(const Option &O) const {
1418   size_t Len = O.ArgStr.size();
1419   auto ValName = getValueName();
1420   if (!ValName.empty())
1421     Len += getValueStr(O, ValName).size() + 3;
1422 
1423   return Len + 6;
1424 }
1425 
1426 // printOptionInfo - Print out information about this option.  The
1427 // to-be-maintained width is specified.
1428 //
1429 void basic_parser_impl::printOptionInfo(const Option &O,
1430                                         size_t GlobalWidth) const {
1431   outs() << "  -" << O.ArgStr;
1432 
1433   auto ValName = getValueName();
1434   if (!ValName.empty())
1435     outs() << "=<" << getValueStr(O, ValName) << '>';
1436 
1437   Option::printHelpStr(O.HelpStr, GlobalWidth, getOptionWidth(O));
1438 }
1439 
1440 void basic_parser_impl::printOptionName(const Option &O,
1441                                         size_t GlobalWidth) const {
1442   outs() << "  -" << O.ArgStr;
1443   outs().indent(GlobalWidth - O.ArgStr.size());
1444 }
1445 
1446 // parser<bool> implementation
1447 //
1448 bool parser<bool>::parse(Option &O, StringRef ArgName, StringRef Arg,
1449                          bool &Value) {
1450   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
1451       Arg == "1") {
1452     Value = true;
1453     return false;
1454   }
1455 
1456   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
1457     Value = false;
1458     return false;
1459   }
1460   return O.error("'" + Arg +
1461                  "' is invalid value for boolean argument! Try 0 or 1");
1462 }
1463 
1464 // parser<boolOrDefault> implementation
1465 //
1466 bool parser<boolOrDefault>::parse(Option &O, StringRef ArgName, StringRef Arg,
1467                                   boolOrDefault &Value) {
1468   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
1469       Arg == "1") {
1470     Value = BOU_TRUE;
1471     return false;
1472   }
1473   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
1474     Value = BOU_FALSE;
1475     return false;
1476   }
1477 
1478   return O.error("'" + Arg +
1479                  "' is invalid value for boolean argument! Try 0 or 1");
1480 }
1481 
1482 // parser<int> implementation
1483 //
1484 bool parser<int>::parse(Option &O, StringRef ArgName, StringRef Arg,
1485                         int &Value) {
1486   if (Arg.getAsInteger(0, Value))
1487     return O.error("'" + Arg + "' value invalid for integer argument!");
1488   return false;
1489 }
1490 
1491 // parser<unsigned> implementation
1492 //
1493 bool parser<unsigned>::parse(Option &O, StringRef ArgName, StringRef Arg,
1494                              unsigned &Value) {
1495 
1496   if (Arg.getAsInteger(0, Value))
1497     return O.error("'" + Arg + "' value invalid for uint argument!");
1498   return false;
1499 }
1500 
1501 // parser<unsigned long long> implementation
1502 //
1503 bool parser<unsigned long long>::parse(Option &O, StringRef ArgName,
1504                                        StringRef Arg,
1505                                        unsigned long long &Value) {
1506 
1507   if (Arg.getAsInteger(0, Value))
1508     return O.error("'" + Arg + "' value invalid for uint argument!");
1509   return false;
1510 }
1511 
1512 // parser<double>/parser<float> implementation
1513 //
1514 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
1515   if (to_float(Arg, Value))
1516     return false;
1517   return O.error("'" + Arg + "' value invalid for floating point argument!");
1518 }
1519 
1520 bool parser<double>::parse(Option &O, StringRef ArgName, StringRef Arg,
1521                            double &Val) {
1522   return parseDouble(O, Arg, Val);
1523 }
1524 
1525 bool parser<float>::parse(Option &O, StringRef ArgName, StringRef Arg,
1526                           float &Val) {
1527   double dVal;
1528   if (parseDouble(O, Arg, dVal))
1529     return true;
1530   Val = (float)dVal;
1531   return false;
1532 }
1533 
1534 // generic_parser_base implementation
1535 //
1536 
1537 // findOption - Return the option number corresponding to the specified
1538 // argument string.  If the option is not found, getNumOptions() is returned.
1539 //
1540 unsigned generic_parser_base::findOption(StringRef Name) {
1541   unsigned e = getNumOptions();
1542 
1543   for (unsigned i = 0; i != e; ++i) {
1544     if (getOption(i) == Name)
1545       return i;
1546   }
1547   return e;
1548 }
1549 
1550 // Return the width of the option tag for printing...
1551 size_t generic_parser_base::getOptionWidth(const Option &O) const {
1552   if (O.hasArgStr()) {
1553     size_t Size = O.ArgStr.size() + 6;
1554     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
1555       Size = std::max(Size, getOption(i).size() + 8);
1556     return Size;
1557   } else {
1558     size_t BaseSize = 0;
1559     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
1560       BaseSize = std::max(BaseSize, getOption(i).size() + 8);
1561     return BaseSize;
1562   }
1563 }
1564 
1565 // printOptionInfo - Print out information about this option.  The
1566 // to-be-maintained width is specified.
1567 //
1568 void generic_parser_base::printOptionInfo(const Option &O,
1569                                           size_t GlobalWidth) const {
1570   if (O.hasArgStr()) {
1571     outs() << "  -" << O.ArgStr;
1572     Option::printHelpStr(O.HelpStr, GlobalWidth, O.ArgStr.size() + 6);
1573 
1574     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1575       size_t NumSpaces = GlobalWidth - getOption(i).size() - 8;
1576       outs() << "    =" << getOption(i);
1577       outs().indent(NumSpaces) << " -   " << getDescription(i) << '\n';
1578     }
1579   } else {
1580     if (!O.HelpStr.empty())
1581       outs() << "  " << O.HelpStr << '\n';
1582     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1583       auto Option = getOption(i);
1584       outs() << "    -" << Option;
1585       Option::printHelpStr(getDescription(i), GlobalWidth, Option.size() + 8);
1586     }
1587   }
1588 }
1589 
1590 static const size_t MaxOptWidth = 8; // arbitrary spacing for printOptionDiff
1591 
1592 // printGenericOptionDiff - Print the value of this option and it's default.
1593 //
1594 // "Generic" options have each value mapped to a name.
1595 void generic_parser_base::printGenericOptionDiff(
1596     const Option &O, const GenericOptionValue &Value,
1597     const GenericOptionValue &Default, size_t GlobalWidth) const {
1598   outs() << "  -" << O.ArgStr;
1599   outs().indent(GlobalWidth - O.ArgStr.size());
1600 
1601   unsigned NumOpts = getNumOptions();
1602   for (unsigned i = 0; i != NumOpts; ++i) {
1603     if (Value.compare(getOptionValue(i)))
1604       continue;
1605 
1606     outs() << "= " << getOption(i);
1607     size_t L = getOption(i).size();
1608     size_t NumSpaces = MaxOptWidth > L ? MaxOptWidth - L : 0;
1609     outs().indent(NumSpaces) << " (default: ";
1610     for (unsigned j = 0; j != NumOpts; ++j) {
1611       if (Default.compare(getOptionValue(j)))
1612         continue;
1613       outs() << getOption(j);
1614       break;
1615     }
1616     outs() << ")\n";
1617     return;
1618   }
1619   outs() << "= *unknown option value*\n";
1620 }
1621 
1622 // printOptionDiff - Specializations for printing basic value types.
1623 //
1624 #define PRINT_OPT_DIFF(T)                                                      \
1625   void parser<T>::printOptionDiff(const Option &O, T V, OptionValue<T> D,      \
1626                                   size_t GlobalWidth) const {                  \
1627     printOptionName(O, GlobalWidth);                                           \
1628     std::string Str;                                                           \
1629     {                                                                          \
1630       raw_string_ostream SS(Str);                                              \
1631       SS << V;                                                                 \
1632     }                                                                          \
1633     outs() << "= " << Str;                                                     \
1634     size_t NumSpaces =                                                         \
1635         MaxOptWidth > Str.size() ? MaxOptWidth - Str.size() : 0;               \
1636     outs().indent(NumSpaces) << " (default: ";                                 \
1637     if (D.hasValue())                                                          \
1638       outs() << D.getValue();                                                  \
1639     else                                                                       \
1640       outs() << "*no default*";                                                \
1641     outs() << ")\n";                                                           \
1642   }
1643 
1644 PRINT_OPT_DIFF(bool)
1645 PRINT_OPT_DIFF(boolOrDefault)
1646 PRINT_OPT_DIFF(int)
1647 PRINT_OPT_DIFF(unsigned)
1648 PRINT_OPT_DIFF(unsigned long long)
1649 PRINT_OPT_DIFF(double)
1650 PRINT_OPT_DIFF(float)
1651 PRINT_OPT_DIFF(char)
1652 
1653 void parser<std::string>::printOptionDiff(const Option &O, StringRef V,
1654                                           const OptionValue<std::string> &D,
1655                                           size_t GlobalWidth) const {
1656   printOptionName(O, GlobalWidth);
1657   outs() << "= " << V;
1658   size_t NumSpaces = MaxOptWidth > V.size() ? MaxOptWidth - V.size() : 0;
1659   outs().indent(NumSpaces) << " (default: ";
1660   if (D.hasValue())
1661     outs() << D.getValue();
1662   else
1663     outs() << "*no default*";
1664   outs() << ")\n";
1665 }
1666 
1667 // Print a placeholder for options that don't yet support printOptionDiff().
1668 void basic_parser_impl::printOptionNoValue(const Option &O,
1669                                            size_t GlobalWidth) const {
1670   printOptionName(O, GlobalWidth);
1671   outs() << "= *cannot print option value*\n";
1672 }
1673 
1674 //===----------------------------------------------------------------------===//
1675 // -help and -help-hidden option implementation
1676 //
1677 
1678 static int OptNameCompare(const std::pair<const char *, Option *> *LHS,
1679                           const std::pair<const char *, Option *> *RHS) {
1680   return strcmp(LHS->first, RHS->first);
1681 }
1682 
1683 static int SubNameCompare(const std::pair<const char *, SubCommand *> *LHS,
1684                           const std::pair<const char *, SubCommand *> *RHS) {
1685   return strcmp(LHS->first, RHS->first);
1686 }
1687 
1688 // Copy Options into a vector so we can sort them as we like.
1689 static void sortOpts(StringMap<Option *> &OptMap,
1690                      SmallVectorImpl<std::pair<const char *, Option *>> &Opts,
1691                      bool ShowHidden) {
1692   SmallPtrSet<Option *, 32> OptionSet; // Duplicate option detection.
1693 
1694   for (StringMap<Option *>::iterator I = OptMap.begin(), E = OptMap.end();
1695        I != E; ++I) {
1696     // Ignore really-hidden options.
1697     if (I->second->getOptionHiddenFlag() == ReallyHidden)
1698       continue;
1699 
1700     // Unless showhidden is set, ignore hidden flags.
1701     if (I->second->getOptionHiddenFlag() == Hidden && !ShowHidden)
1702       continue;
1703 
1704     // If we've already seen this option, don't add it to the list again.
1705     if (!OptionSet.insert(I->second).second)
1706       continue;
1707 
1708     Opts.push_back(
1709         std::pair<const char *, Option *>(I->getKey().data(), I->second));
1710   }
1711 
1712   // Sort the options list alphabetically.
1713   array_pod_sort(Opts.begin(), Opts.end(), OptNameCompare);
1714 }
1715 
1716 static void
1717 sortSubCommands(const SmallPtrSetImpl<SubCommand *> &SubMap,
1718                 SmallVectorImpl<std::pair<const char *, SubCommand *>> &Subs) {
1719   for (const auto &S : SubMap) {
1720     if (S->getName().empty())
1721       continue;
1722     Subs.push_back(std::make_pair(S->getName().data(), S));
1723   }
1724   array_pod_sort(Subs.begin(), Subs.end(), SubNameCompare);
1725 }
1726 
1727 namespace {
1728 
1729 class HelpPrinter {
1730 protected:
1731   const bool ShowHidden;
1732   typedef SmallVector<std::pair<const char *, Option *>, 128>
1733       StrOptionPairVector;
1734   typedef SmallVector<std::pair<const char *, SubCommand *>, 128>
1735       StrSubCommandPairVector;
1736   // Print the options. Opts is assumed to be alphabetically sorted.
1737   virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
1738     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1739       Opts[i].second->printOptionInfo(MaxArgLen);
1740   }
1741 
1742   void printSubCommands(StrSubCommandPairVector &Subs, size_t MaxSubLen) {
1743     for (const auto &S : Subs) {
1744       outs() << "  " << S.first;
1745       if (!S.second->getDescription().empty()) {
1746         outs().indent(MaxSubLen - strlen(S.first));
1747         outs() << " - " << S.second->getDescription();
1748       }
1749       outs() << "\n";
1750     }
1751   }
1752 
1753 public:
1754   explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {}
1755   virtual ~HelpPrinter() {}
1756 
1757   // Invoke the printer.
1758   void operator=(bool Value) {
1759     if (!Value)
1760       return;
1761     printHelp();
1762 
1763     // Halt the program since help information was printed
1764     exit(0);
1765   }
1766 
1767   void printHelp() {
1768     SubCommand *Sub = GlobalParser->getActiveSubCommand();
1769     auto &OptionsMap = Sub->OptionsMap;
1770     auto &PositionalOpts = Sub->PositionalOpts;
1771     auto &ConsumeAfterOpt = Sub->ConsumeAfterOpt;
1772 
1773     StrOptionPairVector Opts;
1774     sortOpts(OptionsMap, Opts, ShowHidden);
1775 
1776     StrSubCommandPairVector Subs;
1777     sortSubCommands(GlobalParser->RegisteredSubCommands, Subs);
1778 
1779     if (!GlobalParser->ProgramOverview.empty())
1780       outs() << "OVERVIEW: " << GlobalParser->ProgramOverview << "\n";
1781 
1782     if (Sub == &*TopLevelSubCommand) {
1783       outs() << "USAGE: " << GlobalParser->ProgramName;
1784       if (Subs.size() > 2)
1785         outs() << " [subcommand]";
1786       outs() << " [options]";
1787     } else {
1788       if (!Sub->getDescription().empty()) {
1789         outs() << "SUBCOMMAND '" << Sub->getName()
1790                << "': " << Sub->getDescription() << "\n\n";
1791       }
1792       outs() << "USAGE: " << GlobalParser->ProgramName << " " << Sub->getName()
1793              << " [options]";
1794     }
1795 
1796     for (auto Opt : PositionalOpts) {
1797       if (Opt->hasArgStr())
1798         outs() << " --" << Opt->ArgStr;
1799       outs() << " " << Opt->HelpStr;
1800     }
1801 
1802     // Print the consume after option info if it exists...
1803     if (ConsumeAfterOpt)
1804       outs() << " " << ConsumeAfterOpt->HelpStr;
1805 
1806     if (Sub == &*TopLevelSubCommand && !Subs.empty()) {
1807       // Compute the maximum subcommand length...
1808       size_t MaxSubLen = 0;
1809       for (size_t i = 0, e = Subs.size(); i != e; ++i)
1810         MaxSubLen = std::max(MaxSubLen, strlen(Subs[i].first));
1811 
1812       outs() << "\n\n";
1813       outs() << "SUBCOMMANDS:\n\n";
1814       printSubCommands(Subs, MaxSubLen);
1815       outs() << "\n";
1816       outs() << "  Type \"" << GlobalParser->ProgramName
1817              << " <subcommand> -help\" to get more help on a specific "
1818                 "subcommand";
1819     }
1820 
1821     outs() << "\n\n";
1822 
1823     // Compute the maximum argument length...
1824     size_t MaxArgLen = 0;
1825     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1826       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
1827 
1828     outs() << "OPTIONS:\n";
1829     printOptions(Opts, MaxArgLen);
1830 
1831     // Print any extra help the user has declared.
1832     for (auto I : GlobalParser->MoreHelp)
1833       outs() << I;
1834     GlobalParser->MoreHelp.clear();
1835   }
1836 };
1837 
1838 class CategorizedHelpPrinter : public HelpPrinter {
1839 public:
1840   explicit CategorizedHelpPrinter(bool showHidden) : HelpPrinter(showHidden) {}
1841 
1842   // Helper function for printOptions().
1843   // It shall return a negative value if A's name should be lexicographically
1844   // ordered before B's name. It returns a value greater than zero if B's name
1845   // should be ordered before A's name, and it returns 0 otherwise.
1846   static int OptionCategoryCompare(OptionCategory *const *A,
1847                                    OptionCategory *const *B) {
1848     return (*A)->getName().compare((*B)->getName());
1849   }
1850 
1851   // Make sure we inherit our base class's operator=()
1852   using HelpPrinter::operator=;
1853 
1854 protected:
1855   void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) override {
1856     std::vector<OptionCategory *> SortedCategories;
1857     std::map<OptionCategory *, std::vector<Option *>> CategorizedOptions;
1858 
1859     // Collect registered option categories into vector in preparation for
1860     // sorting.
1861     for (auto I = GlobalParser->RegisteredOptionCategories.begin(),
1862               E = GlobalParser->RegisteredOptionCategories.end();
1863          I != E; ++I) {
1864       SortedCategories.push_back(*I);
1865     }
1866 
1867     // Sort the different option categories alphabetically.
1868     assert(SortedCategories.size() > 0 && "No option categories registered!");
1869     array_pod_sort(SortedCategories.begin(), SortedCategories.end(),
1870                    OptionCategoryCompare);
1871 
1872     // Create map to empty vectors.
1873     for (std::vector<OptionCategory *>::const_iterator
1874              I = SortedCategories.begin(),
1875              E = SortedCategories.end();
1876          I != E; ++I)
1877       CategorizedOptions[*I] = std::vector<Option *>();
1878 
1879     // Walk through pre-sorted options and assign into categories.
1880     // Because the options are already alphabetically sorted the
1881     // options within categories will also be alphabetically sorted.
1882     for (size_t I = 0, E = Opts.size(); I != E; ++I) {
1883       Option *Opt = Opts[I].second;
1884       assert(CategorizedOptions.count(Opt->Category) > 0 &&
1885              "Option has an unregistered category");
1886       CategorizedOptions[Opt->Category].push_back(Opt);
1887     }
1888 
1889     // Now do printing.
1890     for (std::vector<OptionCategory *>::const_iterator
1891              Category = SortedCategories.begin(),
1892              E = SortedCategories.end();
1893          Category != E; ++Category) {
1894       // Hide empty categories for -help, but show for -help-hidden.
1895       const auto &CategoryOptions = CategorizedOptions[*Category];
1896       bool IsEmptyCategory = CategoryOptions.empty();
1897       if (!ShowHidden && IsEmptyCategory)
1898         continue;
1899 
1900       // Print category information.
1901       outs() << "\n";
1902       outs() << (*Category)->getName() << ":\n";
1903 
1904       // Check if description is set.
1905       if (!(*Category)->getDescription().empty())
1906         outs() << (*Category)->getDescription() << "\n\n";
1907       else
1908         outs() << "\n";
1909 
1910       // When using -help-hidden explicitly state if the category has no
1911       // options associated with it.
1912       if (IsEmptyCategory) {
1913         outs() << "  This option category has no options.\n";
1914         continue;
1915       }
1916       // Loop over the options in the category and print.
1917       for (const Option *Opt : CategoryOptions)
1918         Opt->printOptionInfo(MaxArgLen);
1919     }
1920   }
1921 };
1922 
1923 // This wraps the Uncategorizing and Categorizing printers and decides
1924 // at run time which should be invoked.
1925 class HelpPrinterWrapper {
1926 private:
1927   HelpPrinter &UncategorizedPrinter;
1928   CategorizedHelpPrinter &CategorizedPrinter;
1929 
1930 public:
1931   explicit HelpPrinterWrapper(HelpPrinter &UncategorizedPrinter,
1932                               CategorizedHelpPrinter &CategorizedPrinter)
1933       : UncategorizedPrinter(UncategorizedPrinter),
1934         CategorizedPrinter(CategorizedPrinter) {}
1935 
1936   // Invoke the printer.
1937   void operator=(bool Value);
1938 };
1939 
1940 } // End anonymous namespace
1941 
1942 // Declare the four HelpPrinter instances that are used to print out help, or
1943 // help-hidden as an uncategorized list or in categories.
1944 static HelpPrinter UncategorizedNormalPrinter(false);
1945 static HelpPrinter UncategorizedHiddenPrinter(true);
1946 static CategorizedHelpPrinter CategorizedNormalPrinter(false);
1947 static CategorizedHelpPrinter CategorizedHiddenPrinter(true);
1948 
1949 // Declare HelpPrinter wrappers that will decide whether or not to invoke
1950 // a categorizing help printer
1951 static HelpPrinterWrapper WrappedNormalPrinter(UncategorizedNormalPrinter,
1952                                                CategorizedNormalPrinter);
1953 static HelpPrinterWrapper WrappedHiddenPrinter(UncategorizedHiddenPrinter,
1954                                                CategorizedHiddenPrinter);
1955 
1956 // Define a category for generic options that all tools should have.
1957 static cl::OptionCategory GenericCategory("Generic Options");
1958 
1959 // Define uncategorized help printers.
1960 // -help-list is hidden by default because if Option categories are being used
1961 // then -help behaves the same as -help-list.
1962 static cl::opt<HelpPrinter, true, parser<bool>> HLOp(
1963     "help-list",
1964     cl::desc("Display list of available options (-help-list-hidden for more)"),
1965     cl::location(UncategorizedNormalPrinter), cl::Hidden, cl::ValueDisallowed,
1966     cl::cat(GenericCategory), cl::sub(*AllSubCommands));
1967 
1968 static cl::opt<HelpPrinter, true, parser<bool>>
1969     HLHOp("help-list-hidden", cl::desc("Display list of all available options"),
1970           cl::location(UncategorizedHiddenPrinter), cl::Hidden,
1971           cl::ValueDisallowed, cl::cat(GenericCategory),
1972           cl::sub(*AllSubCommands));
1973 
1974 // Define uncategorized/categorized help printers. These printers change their
1975 // behaviour at runtime depending on whether one or more Option categories have
1976 // been declared.
1977 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
1978     HOp("help", cl::desc("Display available options (-help-hidden for more)"),
1979         cl::location(WrappedNormalPrinter), cl::ValueDisallowed,
1980         cl::cat(GenericCategory), cl::sub(*AllSubCommands));
1981 
1982 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
1983     HHOp("help-hidden", cl::desc("Display all available options"),
1984          cl::location(WrappedHiddenPrinter), cl::Hidden, cl::ValueDisallowed,
1985          cl::cat(GenericCategory), cl::sub(*AllSubCommands));
1986 
1987 static cl::opt<bool> PrintOptions(
1988     "print-options",
1989     cl::desc("Print non-default options after command line parsing"),
1990     cl::Hidden, cl::init(false), cl::cat(GenericCategory),
1991     cl::sub(*AllSubCommands));
1992 
1993 static cl::opt<bool> PrintAllOptions(
1994     "print-all-options",
1995     cl::desc("Print all option values after command line parsing"), cl::Hidden,
1996     cl::init(false), cl::cat(GenericCategory), cl::sub(*AllSubCommands));
1997 
1998 void HelpPrinterWrapper::operator=(bool Value) {
1999   if (!Value)
2000     return;
2001 
2002   // Decide which printer to invoke. If more than one option category is
2003   // registered then it is useful to show the categorized help instead of
2004   // uncategorized help.
2005   if (GlobalParser->RegisteredOptionCategories.size() > 1) {
2006     // unhide -help-list option so user can have uncategorized output if they
2007     // want it.
2008     HLOp.setHiddenFlag(NotHidden);
2009 
2010     CategorizedPrinter = true; // Invoke categorized printer
2011   } else
2012     UncategorizedPrinter = true; // Invoke uncategorized printer
2013 }
2014 
2015 // Print the value of each option.
2016 void cl::PrintOptionValues() { GlobalParser->printOptionValues(); }
2017 
2018 void CommandLineParser::printOptionValues() {
2019   if (!PrintOptions && !PrintAllOptions)
2020     return;
2021 
2022   SmallVector<std::pair<const char *, Option *>, 128> Opts;
2023   sortOpts(ActiveSubCommand->OptionsMap, Opts, /*ShowHidden*/ true);
2024 
2025   // Compute the maximum argument length...
2026   size_t MaxArgLen = 0;
2027   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2028     MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
2029 
2030   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2031     Opts[i].second->printOptionValue(MaxArgLen, PrintAllOptions);
2032 }
2033 
2034 static VersionPrinterTy OverrideVersionPrinter = nullptr;
2035 
2036 static std::vector<VersionPrinterTy> *ExtraVersionPrinters = nullptr;
2037 
2038 namespace {
2039 class VersionPrinter {
2040 public:
2041   void print() {
2042     raw_ostream &OS = outs();
2043 #ifdef PACKAGE_VENDOR
2044     OS << PACKAGE_VENDOR << " ";
2045 #else
2046     OS << "LLVM (http://llvm.org/):\n  ";
2047 #endif
2048     OS << PACKAGE_NAME << " version " << PACKAGE_VERSION;
2049 #ifdef LLVM_VERSION_INFO
2050     OS << " " << LLVM_VERSION_INFO;
2051 #endif
2052     OS << "\n  ";
2053 #ifndef __OPTIMIZE__
2054     OS << "DEBUG build";
2055 #else
2056     OS << "Optimized build";
2057 #endif
2058 #ifndef NDEBUG
2059     OS << " with assertions";
2060 #endif
2061 #if LLVM_VERSION_PRINTER_SHOW_HOST_TARGET_INFO
2062     std::string CPU = sys::getHostCPUName();
2063     if (CPU == "generic")
2064       CPU = "(unknown)";
2065     OS << ".\n"
2066        << "  Default target: " << sys::getDefaultTargetTriple() << '\n'
2067        << "  Host CPU: " << CPU;
2068 #endif
2069     OS << '\n';
2070   }
2071   void operator=(bool OptionWasSpecified) {
2072     if (!OptionWasSpecified)
2073       return;
2074 
2075     if (OverrideVersionPrinter != nullptr) {
2076       OverrideVersionPrinter(outs());
2077       exit(0);
2078     }
2079     print();
2080 
2081     // Iterate over any registered extra printers and call them to add further
2082     // information.
2083     if (ExtraVersionPrinters != nullptr) {
2084       outs() << '\n';
2085       for (auto I : *ExtraVersionPrinters)
2086         I(outs());
2087     }
2088 
2089     exit(0);
2090   }
2091 };
2092 } // End anonymous namespace
2093 
2094 // Define the --version option that prints out the LLVM version for the tool
2095 static VersionPrinter VersionPrinterInstance;
2096 
2097 static cl::opt<VersionPrinter, true, parser<bool>>
2098     VersOp("version", cl::desc("Display the version of this program"),
2099            cl::location(VersionPrinterInstance), cl::ValueDisallowed,
2100            cl::cat(GenericCategory));
2101 
2102 // Utility function for printing the help message.
2103 void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
2104   if (!Hidden && !Categorized)
2105     UncategorizedNormalPrinter.printHelp();
2106   else if (!Hidden && Categorized)
2107     CategorizedNormalPrinter.printHelp();
2108   else if (Hidden && !Categorized)
2109     UncategorizedHiddenPrinter.printHelp();
2110   else
2111     CategorizedHiddenPrinter.printHelp();
2112 }
2113 
2114 /// Utility function for printing version number.
2115 void cl::PrintVersionMessage() { VersionPrinterInstance.print(); }
2116 
2117 void cl::SetVersionPrinter(VersionPrinterTy func) { OverrideVersionPrinter = func; }
2118 
2119 void cl::AddExtraVersionPrinter(VersionPrinterTy func) {
2120   if (!ExtraVersionPrinters)
2121     ExtraVersionPrinters = new std::vector<VersionPrinterTy>;
2122 
2123   ExtraVersionPrinters->push_back(func);
2124 }
2125 
2126 StringMap<Option *> &cl::getRegisteredOptions(SubCommand &Sub) {
2127   auto &Subs = GlobalParser->RegisteredSubCommands;
2128   (void)Subs;
2129   assert(is_contained(Subs, &Sub));
2130   return Sub.OptionsMap;
2131 }
2132 
2133 iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
2134 cl::getRegisteredSubcommands() {
2135   return GlobalParser->getRegisteredSubcommands();
2136 }
2137 
2138 void cl::HideUnrelatedOptions(cl::OptionCategory &Category, SubCommand &Sub) {
2139   for (auto &I : Sub.OptionsMap) {
2140     if (I.second->Category != &Category &&
2141         I.second->Category != &GenericCategory)
2142       I.second->setHiddenFlag(cl::ReallyHidden);
2143   }
2144 }
2145 
2146 void cl::HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
2147                               SubCommand &Sub) {
2148   auto CategoriesBegin = Categories.begin();
2149   auto CategoriesEnd = Categories.end();
2150   for (auto &I : Sub.OptionsMap) {
2151     if (std::find(CategoriesBegin, CategoriesEnd, I.second->Category) ==
2152             CategoriesEnd &&
2153         I.second->Category != &GenericCategory)
2154       I.second->setHiddenFlag(cl::ReallyHidden);
2155   }
2156 }
2157 
2158 void cl::ResetCommandLineParser() { GlobalParser->reset(); }
2159 void cl::ResetAllOptionOccurrences() {
2160   GlobalParser->ResetAllOptionOccurrences();
2161 }
2162 
2163 void LLVMParseCommandLineOptions(int argc, const char *const *argv,
2164                                  const char *Overview) {
2165   llvm::cl::ParseCommandLineOptions(argc, argv, StringRef(Overview),
2166                                     &llvm::nulls());
2167 }
2168