xref: /llvm-project/llvm/lib/Support/CommandLine.cpp (revision d34e60ca8532511acb8c93ef26297e349fbec86a)
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/Optional.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/ADT/SmallPtrSet.h"
25 #include "llvm/ADT/SmallString.h"
26 #include "llvm/ADT/StringExtras.h"
27 #include "llvm/ADT/StringMap.h"
28 #include "llvm/ADT/Triple.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) {
693   return C == ' ' || C == '\t' || C == '\r' || C == '\n';
694 }
695 
696 static bool isQuote(char C) { return C == '\"' || C == '\''; }
697 
698 void cl::TokenizeGNUCommandLine(StringRef Src, StringSaver &Saver,
699                                 SmallVectorImpl<const char *> &NewArgv,
700                                 bool MarkEOLs) {
701   SmallString<128> Token;
702   for (size_t I = 0, E = Src.size(); I != E; ++I) {
703     // Consume runs of whitespace.
704     if (Token.empty()) {
705       while (I != E && isWhitespace(Src[I])) {
706         // Mark the end of lines in response files
707         if (MarkEOLs && Src[I] == '\n')
708           NewArgv.push_back(nullptr);
709         ++I;
710       }
711       if (I == E)
712         break;
713     }
714 
715     char C = Src[I];
716 
717     // Backslash escapes the next character.
718     if (I + 1 < E && C == '\\') {
719       ++I; // Skip the escape.
720       Token.push_back(Src[I]);
721       continue;
722     }
723 
724     // Consume a quoted string.
725     if (isQuote(C)) {
726       ++I;
727       while (I != E && Src[I] != C) {
728         // Backslash escapes the next character.
729         if (Src[I] == '\\' && I + 1 != E)
730           ++I;
731         Token.push_back(Src[I]);
732         ++I;
733       }
734       if (I == E)
735         break;
736       continue;
737     }
738 
739     // End the token if this is whitespace.
740     if (isWhitespace(C)) {
741       if (!Token.empty())
742         NewArgv.push_back(Saver.save(StringRef(Token)).data());
743       Token.clear();
744       continue;
745     }
746 
747     // This is a normal character.  Append it.
748     Token.push_back(C);
749   }
750 
751   // Append the last token after hitting EOF with no whitespace.
752   if (!Token.empty())
753     NewArgv.push_back(Saver.save(StringRef(Token)).data());
754   // Mark the end of response files
755   if (MarkEOLs)
756     NewArgv.push_back(nullptr);
757 }
758 
759 /// Backslashes are interpreted in a rather complicated way in the Windows-style
760 /// command line, because backslashes are used both to separate path and to
761 /// escape double quote. This method consumes runs of backslashes as well as the
762 /// following double quote if it's escaped.
763 ///
764 ///  * If an even number of backslashes is followed by a double quote, one
765 ///    backslash is output for every pair of backslashes, and the last double
766 ///    quote remains unconsumed. The double quote will later be interpreted as
767 ///    the start or end of a quoted string in the main loop outside of this
768 ///    function.
769 ///
770 ///  * If an odd number of backslashes is followed by a double quote, one
771 ///    backslash is output for every pair of backslashes, and a double quote is
772 ///    output for the last pair of backslash-double quote. The double quote is
773 ///    consumed in this case.
774 ///
775 ///  * Otherwise, backslashes are interpreted literally.
776 static size_t parseBackslash(StringRef Src, size_t I, SmallString<128> &Token) {
777   size_t E = Src.size();
778   int BackslashCount = 0;
779   // Skip the backslashes.
780   do {
781     ++I;
782     ++BackslashCount;
783   } while (I != E && Src[I] == '\\');
784 
785   bool FollowedByDoubleQuote = (I != E && Src[I] == '"');
786   if (FollowedByDoubleQuote) {
787     Token.append(BackslashCount / 2, '\\');
788     if (BackslashCount % 2 == 0)
789       return I - 1;
790     Token.push_back('"');
791     return I;
792   }
793   Token.append(BackslashCount, '\\');
794   return I - 1;
795 }
796 
797 void cl::TokenizeWindowsCommandLine(StringRef Src, StringSaver &Saver,
798                                     SmallVectorImpl<const char *> &NewArgv,
799                                     bool MarkEOLs) {
800   SmallString<128> Token;
801 
802   // This is a small state machine to consume characters until it reaches the
803   // end of the source string.
804   enum { INIT, UNQUOTED, QUOTED } State = INIT;
805   for (size_t I = 0, E = Src.size(); I != E; ++I) {
806     char C = Src[I];
807 
808     // INIT state indicates that the current input index is at the start of
809     // the string or between tokens.
810     if (State == INIT) {
811       if (isWhitespace(C)) {
812         // Mark the end of lines in response files
813         if (MarkEOLs && C == '\n')
814           NewArgv.push_back(nullptr);
815         continue;
816       }
817       if (C == '"') {
818         State = QUOTED;
819         continue;
820       }
821       if (C == '\\') {
822         I = parseBackslash(Src, I, Token);
823         State = UNQUOTED;
824         continue;
825       }
826       Token.push_back(C);
827       State = UNQUOTED;
828       continue;
829     }
830 
831     // UNQUOTED state means that it's reading a token not quoted by double
832     // quotes.
833     if (State == UNQUOTED) {
834       // Whitespace means the end of the token.
835       if (isWhitespace(C)) {
836         NewArgv.push_back(Saver.save(StringRef(Token)).data());
837         Token.clear();
838         State = INIT;
839         // Mark the end of lines in response files
840         if (MarkEOLs && C == '\n')
841           NewArgv.push_back(nullptr);
842         continue;
843       }
844       if (C == '"') {
845         State = QUOTED;
846         continue;
847       }
848       if (C == '\\') {
849         I = parseBackslash(Src, I, Token);
850         continue;
851       }
852       Token.push_back(C);
853       continue;
854     }
855 
856     // QUOTED state means that it's reading a token quoted by double quotes.
857     if (State == QUOTED) {
858       if (C == '"') {
859         State = UNQUOTED;
860         continue;
861       }
862       if (C == '\\') {
863         I = parseBackslash(Src, I, Token);
864         continue;
865       }
866       Token.push_back(C);
867     }
868   }
869   // Append the last token after hitting EOF with no whitespace.
870   if (!Token.empty())
871     NewArgv.push_back(Saver.save(StringRef(Token)).data());
872   // Mark the end of response files
873   if (MarkEOLs)
874     NewArgv.push_back(nullptr);
875 }
876 
877 void cl::tokenizeConfigFile(StringRef Source, StringSaver &Saver,
878                             SmallVectorImpl<const char *> &NewArgv,
879                             bool MarkEOLs) {
880   for (const char *Cur = Source.begin(); Cur != Source.end();) {
881     SmallString<128> Line;
882     // Check for comment line.
883     if (isWhitespace(*Cur)) {
884       while (Cur != Source.end() && isWhitespace(*Cur))
885         ++Cur;
886       continue;
887     }
888     if (*Cur == '#') {
889       while (Cur != Source.end() && *Cur != '\n')
890         ++Cur;
891       continue;
892     }
893     // Find end of the current line.
894     const char *Start = Cur;
895     for (const char *End = Source.end(); Cur != End; ++Cur) {
896       if (*Cur == '\\') {
897         if (Cur + 1 != End) {
898           ++Cur;
899           if (*Cur == '\n' ||
900               (*Cur == '\r' && (Cur + 1 != End) && Cur[1] == '\n')) {
901             Line.append(Start, Cur - 1);
902             if (*Cur == '\r')
903               ++Cur;
904             Start = Cur + 1;
905           }
906         }
907       } else if (*Cur == '\n')
908         break;
909     }
910     // Tokenize line.
911     Line.append(Start, Cur);
912     cl::TokenizeGNUCommandLine(Line, Saver, NewArgv, MarkEOLs);
913   }
914 }
915 
916 // It is called byte order marker but the UTF-8 BOM is actually not affected
917 // by the host system's endianness.
918 static bool hasUTF8ByteOrderMark(ArrayRef<char> S) {
919   return (S.size() >= 3 && S[0] == '\xef' && S[1] == '\xbb' && S[2] == '\xbf');
920 }
921 
922 static bool ExpandResponseFile(StringRef FName, StringSaver &Saver,
923                                TokenizerCallback Tokenizer,
924                                SmallVectorImpl<const char *> &NewArgv,
925                                bool MarkEOLs, bool RelativeNames) {
926   ErrorOr<std::unique_ptr<MemoryBuffer>> MemBufOrErr =
927       MemoryBuffer::getFile(FName);
928   if (!MemBufOrErr)
929     return false;
930   MemoryBuffer &MemBuf = *MemBufOrErr.get();
931   StringRef Str(MemBuf.getBufferStart(), MemBuf.getBufferSize());
932 
933   // If we have a UTF-16 byte order mark, convert to UTF-8 for parsing.
934   ArrayRef<char> BufRef(MemBuf.getBufferStart(), MemBuf.getBufferEnd());
935   std::string UTF8Buf;
936   if (hasUTF16ByteOrderMark(BufRef)) {
937     if (!convertUTF16ToUTF8String(BufRef, UTF8Buf))
938       return false;
939     Str = StringRef(UTF8Buf);
940   }
941   // If we see UTF-8 BOM sequence at the beginning of a file, we shall remove
942   // these bytes before parsing.
943   // Reference: http://en.wikipedia.org/wiki/UTF-8#Byte_order_mark
944   else if (hasUTF8ByteOrderMark(BufRef))
945     Str = StringRef(BufRef.data() + 3, BufRef.size() - 3);
946 
947   // Tokenize the contents into NewArgv.
948   Tokenizer(Str, Saver, NewArgv, MarkEOLs);
949 
950   // If names of nested response files should be resolved relative to including
951   // file, replace the included response file names with their full paths
952   // obtained by required resolution.
953   if (RelativeNames)
954     for (unsigned I = 0; I < NewArgv.size(); ++I)
955       if (NewArgv[I]) {
956         StringRef Arg = NewArgv[I];
957         if (Arg.front() == '@') {
958           StringRef FileName = Arg.drop_front();
959           if (llvm::sys::path::is_relative(FileName)) {
960             SmallString<128> ResponseFile;
961             ResponseFile.append(1, '@');
962             if (llvm::sys::path::is_relative(FName)) {
963               SmallString<128> curr_dir;
964               llvm::sys::fs::current_path(curr_dir);
965               ResponseFile.append(curr_dir.str());
966             }
967             llvm::sys::path::append(
968                 ResponseFile, llvm::sys::path::parent_path(FName), FileName);
969             NewArgv[I] = Saver.save(ResponseFile.c_str()).data();
970           }
971         }
972       }
973 
974   return true;
975 }
976 
977 /// Expand response files on a command line recursively using the given
978 /// StringSaver and tokenization strategy.
979 bool cl::ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
980                              SmallVectorImpl<const char *> &Argv,
981                              bool MarkEOLs, bool RelativeNames) {
982   unsigned RspFiles = 0;
983   bool AllExpanded = true;
984 
985   // Don't cache Argv.size() because it can change.
986   for (unsigned I = 0; I != Argv.size();) {
987     const char *Arg = Argv[I];
988     // Check if it is an EOL marker
989     if (Arg == nullptr) {
990       ++I;
991       continue;
992     }
993     if (Arg[0] != '@') {
994       ++I;
995       continue;
996     }
997 
998     // If we have too many response files, leave some unexpanded.  This avoids
999     // crashing on self-referential response files.
1000     if (RspFiles++ > 20)
1001       return false;
1002 
1003     // Replace this response file argument with the tokenization of its
1004     // contents.  Nested response files are expanded in subsequent iterations.
1005     SmallVector<const char *, 0> ExpandedArgv;
1006     if (!ExpandResponseFile(Arg + 1, Saver, Tokenizer, ExpandedArgv,
1007                             MarkEOLs, RelativeNames)) {
1008       // We couldn't read this file, so we leave it in the argument stream and
1009       // move on.
1010       AllExpanded = false;
1011       ++I;
1012       continue;
1013     }
1014     Argv.erase(Argv.begin() + I);
1015     Argv.insert(Argv.begin() + I, ExpandedArgv.begin(), ExpandedArgv.end());
1016   }
1017   return AllExpanded;
1018 }
1019 
1020 bool cl::readConfigFile(StringRef CfgFile, StringSaver &Saver,
1021                         SmallVectorImpl<const char *> &Argv) {
1022   if (!ExpandResponseFile(CfgFile, Saver, cl::tokenizeConfigFile, Argv,
1023                           /*MarkEOLs*/ false, /*RelativeNames*/ true))
1024     return false;
1025   return ExpandResponseFiles(Saver, cl::tokenizeConfigFile, Argv,
1026                              /*MarkEOLs*/ false, /*RelativeNames*/ true);
1027 }
1028 
1029 /// ParseEnvironmentOptions - An alternative entry point to the
1030 /// CommandLine library, which allows you to read the program's name
1031 /// from the caller (as PROGNAME) and its command-line arguments from
1032 /// an environment variable (whose name is given in ENVVAR).
1033 ///
1034 void cl::ParseEnvironmentOptions(const char *progName, const char *envVar,
1035                                  const char *Overview) {
1036   // Check args.
1037   assert(progName && "Program name not specified");
1038   assert(envVar && "Environment variable name missing");
1039 
1040   // Get the environment variable they want us to parse options out of.
1041   llvm::Optional<std::string> envValue = sys::Process::GetEnv(StringRef(envVar));
1042   if (!envValue)
1043     return;
1044 
1045   // Get program's "name", which we wouldn't know without the caller
1046   // telling us.
1047   SmallVector<const char *, 20> newArgv;
1048   BumpPtrAllocator A;
1049   StringSaver Saver(A);
1050   newArgv.push_back(Saver.save(progName).data());
1051 
1052   // Parse the value of the environment variable into a "command line"
1053   // and hand it off to ParseCommandLineOptions().
1054   TokenizeGNUCommandLine(*envValue, Saver, newArgv);
1055   int newArgc = static_cast<int>(newArgv.size());
1056   ParseCommandLineOptions(newArgc, &newArgv[0], StringRef(Overview));
1057 }
1058 
1059 bool cl::ParseCommandLineOptions(int argc, const char *const *argv,
1060                                  StringRef Overview, raw_ostream *Errs) {
1061   return GlobalParser->ParseCommandLineOptions(argc, argv, Overview,
1062                                                Errs);
1063 }
1064 
1065 void CommandLineParser::ResetAllOptionOccurrences() {
1066   // So that we can parse different command lines multiple times in succession
1067   // we reset all option values to look like they have never been seen before.
1068   for (auto SC : RegisteredSubCommands) {
1069     for (auto &O : SC->OptionsMap)
1070       O.second->reset();
1071   }
1072 }
1073 
1074 bool CommandLineParser::ParseCommandLineOptions(int argc,
1075                                                 const char *const *argv,
1076                                                 StringRef Overview,
1077                                                 raw_ostream *Errs) {
1078   assert(hasOptions() && "No options specified!");
1079 
1080   // Expand response files.
1081   SmallVector<const char *, 20> newArgv(argv, argv + argc);
1082   BumpPtrAllocator A;
1083   StringSaver Saver(A);
1084   ExpandResponseFiles(Saver,
1085          Triple(sys::getProcessTriple()).isOSWindows() ?
1086          cl::TokenizeWindowsCommandLine : cl::TokenizeGNUCommandLine,
1087          newArgv);
1088   argv = &newArgv[0];
1089   argc = static_cast<int>(newArgv.size());
1090 
1091   // Copy the program name into ProgName, making sure not to overflow it.
1092   ProgramName = sys::path::filename(StringRef(argv[0]));
1093 
1094   ProgramOverview = Overview;
1095   bool IgnoreErrors = Errs;
1096   if (!Errs)
1097     Errs = &errs();
1098   bool ErrorParsing = false;
1099 
1100   // Check out the positional arguments to collect information about them.
1101   unsigned NumPositionalRequired = 0;
1102 
1103   // Determine whether or not there are an unlimited number of positionals
1104   bool HasUnlimitedPositionals = false;
1105 
1106   int FirstArg = 1;
1107   SubCommand *ChosenSubCommand = &*TopLevelSubCommand;
1108   if (argc >= 2 && argv[FirstArg][0] != '-') {
1109     // If the first argument specifies a valid subcommand, start processing
1110     // options from the second argument.
1111     ChosenSubCommand = LookupSubCommand(StringRef(argv[FirstArg]));
1112     if (ChosenSubCommand != &*TopLevelSubCommand)
1113       FirstArg = 2;
1114   }
1115   GlobalParser->ActiveSubCommand = ChosenSubCommand;
1116 
1117   assert(ChosenSubCommand);
1118   auto &ConsumeAfterOpt = ChosenSubCommand->ConsumeAfterOpt;
1119   auto &PositionalOpts = ChosenSubCommand->PositionalOpts;
1120   auto &SinkOpts = ChosenSubCommand->SinkOpts;
1121   auto &OptionsMap = ChosenSubCommand->OptionsMap;
1122 
1123   if (ConsumeAfterOpt) {
1124     assert(PositionalOpts.size() > 0 &&
1125            "Cannot specify cl::ConsumeAfter without a positional argument!");
1126   }
1127   if (!PositionalOpts.empty()) {
1128 
1129     // Calculate how many positional values are _required_.
1130     bool UnboundedFound = false;
1131     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
1132       Option *Opt = PositionalOpts[i];
1133       if (RequiresValue(Opt))
1134         ++NumPositionalRequired;
1135       else if (ConsumeAfterOpt) {
1136         // ConsumeAfter cannot be combined with "optional" positional options
1137         // unless there is only one positional argument...
1138         if (PositionalOpts.size() > 1) {
1139           if (!IgnoreErrors)
1140             Opt->error("error - this positional option will never be matched, "
1141                        "because it does not Require a value, and a "
1142                        "cl::ConsumeAfter option is active!");
1143           ErrorParsing = true;
1144         }
1145       } else if (UnboundedFound && !Opt->hasArgStr()) {
1146         // This option does not "require" a value...  Make sure this option is
1147         // not specified after an option that eats all extra arguments, or this
1148         // one will never get any!
1149         //
1150         if (!IgnoreErrors)
1151           Opt->error("error - option can never match, because "
1152                      "another positional argument will match an "
1153                      "unbounded number of values, and this option"
1154                      " does not require a value!");
1155         *Errs << ProgramName << ": CommandLine Error: Option '" << Opt->ArgStr
1156               << "' is all messed up!\n";
1157         *Errs << PositionalOpts.size();
1158         ErrorParsing = true;
1159       }
1160       UnboundedFound |= EatsUnboundedNumberOfValues(Opt);
1161     }
1162     HasUnlimitedPositionals = UnboundedFound || ConsumeAfterOpt;
1163   }
1164 
1165   // PositionalVals - A vector of "positional" arguments we accumulate into
1166   // the process at the end.
1167   //
1168   SmallVector<std::pair<StringRef, unsigned>, 4> PositionalVals;
1169 
1170   // If the program has named positional arguments, and the name has been run
1171   // across, keep track of which positional argument was named.  Otherwise put
1172   // the positional args into the PositionalVals list...
1173   Option *ActivePositionalArg = nullptr;
1174 
1175   // Loop over all of the arguments... processing them.
1176   bool DashDashFound = false; // Have we read '--'?
1177   for (int i = FirstArg; i < argc; ++i) {
1178     Option *Handler = nullptr;
1179     Option *NearestHandler = nullptr;
1180     std::string NearestHandlerString;
1181     StringRef Value;
1182     StringRef ArgName = "";
1183 
1184     // Check to see if this is a positional argument.  This argument is
1185     // considered to be positional if it doesn't start with '-', if it is "-"
1186     // itself, or if we have seen "--" already.
1187     //
1188     if (argv[i][0] != '-' || argv[i][1] == 0 || DashDashFound) {
1189       // Positional argument!
1190       if (ActivePositionalArg) {
1191         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1192         continue; // We are done!
1193       }
1194 
1195       if (!PositionalOpts.empty()) {
1196         PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1197 
1198         // All of the positional arguments have been fulfulled, give the rest to
1199         // the consume after option... if it's specified...
1200         //
1201         if (PositionalVals.size() >= NumPositionalRequired && ConsumeAfterOpt) {
1202           for (++i; i < argc; ++i)
1203             PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1204           break; // Handle outside of the argument processing loop...
1205         }
1206 
1207         // Delay processing positional arguments until the end...
1208         continue;
1209       }
1210     } else if (argv[i][0] == '-' && argv[i][1] == '-' && argv[i][2] == 0 &&
1211                !DashDashFound) {
1212       DashDashFound = true; // This is the mythical "--"?
1213       continue;             // Don't try to process it as an argument itself.
1214     } else if (ActivePositionalArg &&
1215                (ActivePositionalArg->getMiscFlags() & PositionalEatsArgs)) {
1216       // If there is a positional argument eating options, check to see if this
1217       // option is another positional argument.  If so, treat it as an argument,
1218       // otherwise feed it to the eating positional.
1219       ArgName = StringRef(argv[i] + 1);
1220       // Eat leading dashes.
1221       while (!ArgName.empty() && ArgName[0] == '-')
1222         ArgName = ArgName.substr(1);
1223 
1224       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
1225       if (!Handler || Handler->getFormattingFlag() != cl::Positional) {
1226         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1227         continue; // We are done!
1228       }
1229 
1230     } else { // We start with a '-', must be an argument.
1231       ArgName = StringRef(argv[i] + 1);
1232       // Eat leading dashes.
1233       while (!ArgName.empty() && ArgName[0] == '-')
1234         ArgName = ArgName.substr(1);
1235 
1236       Handler = LookupOption(*ChosenSubCommand, ArgName, Value);
1237 
1238       // Check to see if this "option" is really a prefixed or grouped argument.
1239       if (!Handler)
1240         Handler = HandlePrefixedOrGroupedOption(ArgName, Value, ErrorParsing,
1241                                                 OptionsMap);
1242 
1243       // Otherwise, look for the closest available option to report to the user
1244       // in the upcoming error.
1245       if (!Handler && SinkOpts.empty())
1246         NearestHandler =
1247             LookupNearestOption(ArgName, OptionsMap, NearestHandlerString);
1248     }
1249 
1250     if (!Handler) {
1251       if (SinkOpts.empty()) {
1252         *Errs << ProgramName << ": Unknown command line argument '" << argv[i]
1253               << "'.  Try: '" << argv[0] << " -help'\n";
1254 
1255         if (NearestHandler) {
1256           // If we know a near match, report it as well.
1257           *Errs << ProgramName << ": Did you mean '-" << NearestHandlerString
1258                  << "'?\n";
1259         }
1260 
1261         ErrorParsing = true;
1262       } else {
1263         for (SmallVectorImpl<Option *>::iterator I = SinkOpts.begin(),
1264                                                  E = SinkOpts.end();
1265              I != E; ++I)
1266           (*I)->addOccurrence(i, "", StringRef(argv[i]));
1267       }
1268       continue;
1269     }
1270 
1271     // If this is a named positional argument, just remember that it is the
1272     // active one...
1273     if (Handler->getFormattingFlag() == cl::Positional)
1274       ActivePositionalArg = Handler;
1275     else
1276       ErrorParsing |= ProvideOption(Handler, ArgName, Value, argc, argv, i);
1277   }
1278 
1279   // Check and handle positional arguments now...
1280   if (NumPositionalRequired > PositionalVals.size()) {
1281       *Errs << ProgramName
1282              << ": Not enough positional command line arguments specified!\n"
1283              << "Must specify at least " << NumPositionalRequired
1284              << " positional argument" << (NumPositionalRequired > 1 ? "s" : "")
1285              << ": See: " << argv[0] << " -help\n";
1286 
1287     ErrorParsing = true;
1288   } else if (!HasUnlimitedPositionals &&
1289              PositionalVals.size() > PositionalOpts.size()) {
1290     *Errs << ProgramName << ": Too many positional arguments specified!\n"
1291           << "Can specify at most " << PositionalOpts.size()
1292           << " positional arguments: See: " << argv[0] << " -help\n";
1293     ErrorParsing = true;
1294 
1295   } else if (!ConsumeAfterOpt) {
1296     // Positional args have already been handled if ConsumeAfter is specified.
1297     unsigned ValNo = 0, NumVals = static_cast<unsigned>(PositionalVals.size());
1298     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
1299       if (RequiresValue(PositionalOpts[i])) {
1300         ProvidePositionalOption(PositionalOpts[i], PositionalVals[ValNo].first,
1301                                 PositionalVals[ValNo].second);
1302         ValNo++;
1303         --NumPositionalRequired; // We fulfilled our duty...
1304       }
1305 
1306       // If we _can_ give this option more arguments, do so now, as long as we
1307       // do not give it values that others need.  'Done' controls whether the
1308       // option even _WANTS_ any more.
1309       //
1310       bool Done = PositionalOpts[i]->getNumOccurrencesFlag() == cl::Required;
1311       while (NumVals - ValNo > NumPositionalRequired && !Done) {
1312         switch (PositionalOpts[i]->getNumOccurrencesFlag()) {
1313         case cl::Optional:
1314           Done = true; // Optional arguments want _at most_ one value
1315           LLVM_FALLTHROUGH;
1316         case cl::ZeroOrMore: // Zero or more will take all they can get...
1317         case cl::OneOrMore:  // One or more will take all they can get...
1318           ProvidePositionalOption(PositionalOpts[i],
1319                                   PositionalVals[ValNo].first,
1320                                   PositionalVals[ValNo].second);
1321           ValNo++;
1322           break;
1323         default:
1324           llvm_unreachable("Internal error, unexpected NumOccurrences flag in "
1325                            "positional argument processing!");
1326         }
1327       }
1328     }
1329   } else {
1330     assert(ConsumeAfterOpt && NumPositionalRequired <= PositionalVals.size());
1331     unsigned ValNo = 0;
1332     for (size_t j = 1, e = PositionalOpts.size(); j != e; ++j)
1333       if (RequiresValue(PositionalOpts[j])) {
1334         ErrorParsing |= ProvidePositionalOption(PositionalOpts[j],
1335                                                 PositionalVals[ValNo].first,
1336                                                 PositionalVals[ValNo].second);
1337         ValNo++;
1338       }
1339 
1340     // Handle the case where there is just one positional option, and it's
1341     // optional.  In this case, we want to give JUST THE FIRST option to the
1342     // positional option and keep the rest for the consume after.  The above
1343     // loop would have assigned no values to positional options in this case.
1344     //
1345     if (PositionalOpts.size() == 1 && ValNo == 0 && !PositionalVals.empty()) {
1346       ErrorParsing |= ProvidePositionalOption(PositionalOpts[0],
1347                                               PositionalVals[ValNo].first,
1348                                               PositionalVals[ValNo].second);
1349       ValNo++;
1350     }
1351 
1352     // Handle over all of the rest of the arguments to the
1353     // cl::ConsumeAfter command line option...
1354     for (; ValNo != PositionalVals.size(); ++ValNo)
1355       ErrorParsing |=
1356           ProvidePositionalOption(ConsumeAfterOpt, PositionalVals[ValNo].first,
1357                                   PositionalVals[ValNo].second);
1358   }
1359 
1360   // Loop over args and make sure all required args are specified!
1361   for (const auto &Opt : OptionsMap) {
1362     switch (Opt.second->getNumOccurrencesFlag()) {
1363     case Required:
1364     case OneOrMore:
1365       if (Opt.second->getNumOccurrences() == 0) {
1366         Opt.second->error("must be specified at least once!");
1367         ErrorParsing = true;
1368       }
1369       LLVM_FALLTHROUGH;
1370     default:
1371       break;
1372     }
1373   }
1374 
1375   // Now that we know if -debug is specified, we can use it.
1376   // Note that if ReadResponseFiles == true, this must be done before the
1377   // memory allocated for the expanded command line is free()d below.
1378   LLVM_DEBUG(dbgs() << "Args: ";
1379              for (int i = 0; i < argc; ++i) dbgs() << argv[i] << ' ';
1380              dbgs() << '\n';);
1381 
1382   // Free all of the memory allocated to the map.  Command line options may only
1383   // be processed once!
1384   MoreHelp.clear();
1385 
1386   // If we had an error processing our arguments, don't let the program execute
1387   if (ErrorParsing) {
1388     if (!IgnoreErrors)
1389       exit(1);
1390     return false;
1391   }
1392   return true;
1393 }
1394 
1395 //===----------------------------------------------------------------------===//
1396 // Option Base class implementation
1397 //
1398 
1399 bool Option::error(const Twine &Message, StringRef ArgName) {
1400   if (!ArgName.data())
1401     ArgName = ArgStr;
1402   if (ArgName.empty())
1403     errs() << HelpStr; // Be nice for positional arguments
1404   else
1405     errs() << GlobalParser->ProgramName << ": for the -" << ArgName;
1406 
1407   errs() << " option: " << Message << "\n";
1408   return true;
1409 }
1410 
1411 bool Option::addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
1412                            bool MultiArg) {
1413   if (!MultiArg)
1414     NumOccurrences++; // Increment the number of times we have been seen
1415 
1416   switch (getNumOccurrencesFlag()) {
1417   case Optional:
1418     if (NumOccurrences > 1)
1419       return error("may only occur zero or one times!", ArgName);
1420     break;
1421   case Required:
1422     if (NumOccurrences > 1)
1423       return error("must occur exactly one time!", ArgName);
1424     LLVM_FALLTHROUGH;
1425   case OneOrMore:
1426   case ZeroOrMore:
1427   case ConsumeAfter:
1428     break;
1429   }
1430 
1431   return handleOccurrence(pos, ArgName, Value);
1432 }
1433 
1434 // getValueStr - Get the value description string, using "DefaultMsg" if nothing
1435 // has been specified yet.
1436 //
1437 static StringRef getValueStr(const Option &O, StringRef DefaultMsg) {
1438   if (O.ValueStr.empty())
1439     return DefaultMsg;
1440   return O.ValueStr;
1441 }
1442 
1443 //===----------------------------------------------------------------------===//
1444 // cl::alias class implementation
1445 //
1446 
1447 // Return the width of the option tag for printing...
1448 size_t alias::getOptionWidth() const { return ArgStr.size() + 6; }
1449 
1450 void Option::printHelpStr(StringRef HelpStr, size_t Indent,
1451                                  size_t FirstLineIndentedBy) {
1452   std::pair<StringRef, StringRef> Split = HelpStr.split('\n');
1453   outs().indent(Indent - FirstLineIndentedBy) << " - " << Split.first << "\n";
1454   while (!Split.second.empty()) {
1455     Split = Split.second.split('\n');
1456     outs().indent(Indent) << Split.first << "\n";
1457   }
1458 }
1459 
1460 // Print out the option for the alias.
1461 void alias::printOptionInfo(size_t GlobalWidth) const {
1462   outs() << "  -" << ArgStr;
1463   printHelpStr(HelpStr, GlobalWidth, ArgStr.size() + 6);
1464 }
1465 
1466 //===----------------------------------------------------------------------===//
1467 // Parser Implementation code...
1468 //
1469 
1470 // basic_parser implementation
1471 //
1472 
1473 // Return the width of the option tag for printing...
1474 size_t basic_parser_impl::getOptionWidth(const Option &O) const {
1475   size_t Len = O.ArgStr.size();
1476   auto ValName = getValueName();
1477   if (!ValName.empty())
1478     Len += getValueStr(O, ValName).size() + 3;
1479 
1480   return Len + 6;
1481 }
1482 
1483 // printOptionInfo - Print out information about this option.  The
1484 // to-be-maintained width is specified.
1485 //
1486 void basic_parser_impl::printOptionInfo(const Option &O,
1487                                         size_t GlobalWidth) const {
1488   outs() << "  -" << O.ArgStr;
1489 
1490   auto ValName = getValueName();
1491   if (!ValName.empty())
1492     outs() << "=<" << getValueStr(O, ValName) << '>';
1493 
1494   Option::printHelpStr(O.HelpStr, GlobalWidth, getOptionWidth(O));
1495 }
1496 
1497 void basic_parser_impl::printOptionName(const Option &O,
1498                                         size_t GlobalWidth) const {
1499   outs() << "  -" << O.ArgStr;
1500   outs().indent(GlobalWidth - O.ArgStr.size());
1501 }
1502 
1503 // parser<bool> implementation
1504 //
1505 bool parser<bool>::parse(Option &O, StringRef ArgName, StringRef Arg,
1506                          bool &Value) {
1507   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
1508       Arg == "1") {
1509     Value = true;
1510     return false;
1511   }
1512 
1513   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
1514     Value = false;
1515     return false;
1516   }
1517   return O.error("'" + Arg +
1518                  "' is invalid value for boolean argument! Try 0 or 1");
1519 }
1520 
1521 // parser<boolOrDefault> implementation
1522 //
1523 bool parser<boolOrDefault>::parse(Option &O, StringRef ArgName, StringRef Arg,
1524                                   boolOrDefault &Value) {
1525   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
1526       Arg == "1") {
1527     Value = BOU_TRUE;
1528     return false;
1529   }
1530   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
1531     Value = BOU_FALSE;
1532     return false;
1533   }
1534 
1535   return O.error("'" + Arg +
1536                  "' is invalid value for boolean argument! Try 0 or 1");
1537 }
1538 
1539 // parser<int> implementation
1540 //
1541 bool parser<int>::parse(Option &O, StringRef ArgName, StringRef Arg,
1542                         int &Value) {
1543   if (Arg.getAsInteger(0, Value))
1544     return O.error("'" + Arg + "' value invalid for integer argument!");
1545   return false;
1546 }
1547 
1548 // parser<unsigned> implementation
1549 //
1550 bool parser<unsigned>::parse(Option &O, StringRef ArgName, StringRef Arg,
1551                              unsigned &Value) {
1552 
1553   if (Arg.getAsInteger(0, Value))
1554     return O.error("'" + Arg + "' value invalid for uint argument!");
1555   return false;
1556 }
1557 
1558 // parser<unsigned long long> implementation
1559 //
1560 bool parser<unsigned long long>::parse(Option &O, StringRef ArgName,
1561                                        StringRef Arg,
1562                                        unsigned long long &Value) {
1563 
1564   if (Arg.getAsInteger(0, Value))
1565     return O.error("'" + Arg + "' value invalid for uint argument!");
1566   return false;
1567 }
1568 
1569 // parser<double>/parser<float> implementation
1570 //
1571 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
1572   if (to_float(Arg, Value))
1573     return false;
1574   return O.error("'" + Arg + "' value invalid for floating point argument!");
1575 }
1576 
1577 bool parser<double>::parse(Option &O, StringRef ArgName, StringRef Arg,
1578                            double &Val) {
1579   return parseDouble(O, Arg, Val);
1580 }
1581 
1582 bool parser<float>::parse(Option &O, StringRef ArgName, StringRef Arg,
1583                           float &Val) {
1584   double dVal;
1585   if (parseDouble(O, Arg, dVal))
1586     return true;
1587   Val = (float)dVal;
1588   return false;
1589 }
1590 
1591 // generic_parser_base implementation
1592 //
1593 
1594 // findOption - Return the option number corresponding to the specified
1595 // argument string.  If the option is not found, getNumOptions() is returned.
1596 //
1597 unsigned generic_parser_base::findOption(StringRef Name) {
1598   unsigned e = getNumOptions();
1599 
1600   for (unsigned i = 0; i != e; ++i) {
1601     if (getOption(i) == Name)
1602       return i;
1603   }
1604   return e;
1605 }
1606 
1607 // Return the width of the option tag for printing...
1608 size_t generic_parser_base::getOptionWidth(const Option &O) const {
1609   if (O.hasArgStr()) {
1610     size_t Size = O.ArgStr.size() + 6;
1611     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
1612       Size = std::max(Size, getOption(i).size() + 8);
1613     return Size;
1614   } else {
1615     size_t BaseSize = 0;
1616     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
1617       BaseSize = std::max(BaseSize, getOption(i).size() + 8);
1618     return BaseSize;
1619   }
1620 }
1621 
1622 // printOptionInfo - Print out information about this option.  The
1623 // to-be-maintained width is specified.
1624 //
1625 void generic_parser_base::printOptionInfo(const Option &O,
1626                                           size_t GlobalWidth) const {
1627   if (O.hasArgStr()) {
1628     outs() << "  -" << O.ArgStr;
1629     Option::printHelpStr(O.HelpStr, GlobalWidth, O.ArgStr.size() + 6);
1630 
1631     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1632       size_t NumSpaces = GlobalWidth - getOption(i).size() - 8;
1633       outs() << "    =" << getOption(i);
1634       outs().indent(NumSpaces) << " -   " << getDescription(i) << '\n';
1635     }
1636   } else {
1637     if (!O.HelpStr.empty())
1638       outs() << "  " << O.HelpStr << '\n';
1639     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1640       auto Option = getOption(i);
1641       outs() << "    -" << Option;
1642       Option::printHelpStr(getDescription(i), GlobalWidth, Option.size() + 8);
1643     }
1644   }
1645 }
1646 
1647 static const size_t MaxOptWidth = 8; // arbitrary spacing for printOptionDiff
1648 
1649 // printGenericOptionDiff - Print the value of this option and it's default.
1650 //
1651 // "Generic" options have each value mapped to a name.
1652 void generic_parser_base::printGenericOptionDiff(
1653     const Option &O, const GenericOptionValue &Value,
1654     const GenericOptionValue &Default, size_t GlobalWidth) const {
1655   outs() << "  -" << O.ArgStr;
1656   outs().indent(GlobalWidth - O.ArgStr.size());
1657 
1658   unsigned NumOpts = getNumOptions();
1659   for (unsigned i = 0; i != NumOpts; ++i) {
1660     if (Value.compare(getOptionValue(i)))
1661       continue;
1662 
1663     outs() << "= " << getOption(i);
1664     size_t L = getOption(i).size();
1665     size_t NumSpaces = MaxOptWidth > L ? MaxOptWidth - L : 0;
1666     outs().indent(NumSpaces) << " (default: ";
1667     for (unsigned j = 0; j != NumOpts; ++j) {
1668       if (Default.compare(getOptionValue(j)))
1669         continue;
1670       outs() << getOption(j);
1671       break;
1672     }
1673     outs() << ")\n";
1674     return;
1675   }
1676   outs() << "= *unknown option value*\n";
1677 }
1678 
1679 // printOptionDiff - Specializations for printing basic value types.
1680 //
1681 #define PRINT_OPT_DIFF(T)                                                      \
1682   void parser<T>::printOptionDiff(const Option &O, T V, OptionValue<T> D,      \
1683                                   size_t GlobalWidth) const {                  \
1684     printOptionName(O, GlobalWidth);                                           \
1685     std::string Str;                                                           \
1686     {                                                                          \
1687       raw_string_ostream SS(Str);                                              \
1688       SS << V;                                                                 \
1689     }                                                                          \
1690     outs() << "= " << Str;                                                     \
1691     size_t NumSpaces =                                                         \
1692         MaxOptWidth > Str.size() ? MaxOptWidth - Str.size() : 0;               \
1693     outs().indent(NumSpaces) << " (default: ";                                 \
1694     if (D.hasValue())                                                          \
1695       outs() << D.getValue();                                                  \
1696     else                                                                       \
1697       outs() << "*no default*";                                                \
1698     outs() << ")\n";                                                           \
1699   }
1700 
1701 PRINT_OPT_DIFF(bool)
1702 PRINT_OPT_DIFF(boolOrDefault)
1703 PRINT_OPT_DIFF(int)
1704 PRINT_OPT_DIFF(unsigned)
1705 PRINT_OPT_DIFF(unsigned long long)
1706 PRINT_OPT_DIFF(double)
1707 PRINT_OPT_DIFF(float)
1708 PRINT_OPT_DIFF(char)
1709 
1710 void parser<std::string>::printOptionDiff(const Option &O, StringRef V,
1711                                           const OptionValue<std::string> &D,
1712                                           size_t GlobalWidth) const {
1713   printOptionName(O, GlobalWidth);
1714   outs() << "= " << V;
1715   size_t NumSpaces = MaxOptWidth > V.size() ? MaxOptWidth - V.size() : 0;
1716   outs().indent(NumSpaces) << " (default: ";
1717   if (D.hasValue())
1718     outs() << D.getValue();
1719   else
1720     outs() << "*no default*";
1721   outs() << ")\n";
1722 }
1723 
1724 // Print a placeholder for options that don't yet support printOptionDiff().
1725 void basic_parser_impl::printOptionNoValue(const Option &O,
1726                                            size_t GlobalWidth) const {
1727   printOptionName(O, GlobalWidth);
1728   outs() << "= *cannot print option value*\n";
1729 }
1730 
1731 //===----------------------------------------------------------------------===//
1732 // -help and -help-hidden option implementation
1733 //
1734 
1735 static int OptNameCompare(const std::pair<const char *, Option *> *LHS,
1736                           const std::pair<const char *, Option *> *RHS) {
1737   return strcmp(LHS->first, RHS->first);
1738 }
1739 
1740 static int SubNameCompare(const std::pair<const char *, SubCommand *> *LHS,
1741                           const std::pair<const char *, SubCommand *> *RHS) {
1742   return strcmp(LHS->first, RHS->first);
1743 }
1744 
1745 // Copy Options into a vector so we can sort them as we like.
1746 static void sortOpts(StringMap<Option *> &OptMap,
1747                      SmallVectorImpl<std::pair<const char *, Option *>> &Opts,
1748                      bool ShowHidden) {
1749   SmallPtrSet<Option *, 32> OptionSet; // Duplicate option detection.
1750 
1751   for (StringMap<Option *>::iterator I = OptMap.begin(), E = OptMap.end();
1752        I != E; ++I) {
1753     // Ignore really-hidden options.
1754     if (I->second->getOptionHiddenFlag() == ReallyHidden)
1755       continue;
1756 
1757     // Unless showhidden is set, ignore hidden flags.
1758     if (I->second->getOptionHiddenFlag() == Hidden && !ShowHidden)
1759       continue;
1760 
1761     // If we've already seen this option, don't add it to the list again.
1762     if (!OptionSet.insert(I->second).second)
1763       continue;
1764 
1765     Opts.push_back(
1766         std::pair<const char *, Option *>(I->getKey().data(), I->second));
1767   }
1768 
1769   // Sort the options list alphabetically.
1770   array_pod_sort(Opts.begin(), Opts.end(), OptNameCompare);
1771 }
1772 
1773 static void
1774 sortSubCommands(const SmallPtrSetImpl<SubCommand *> &SubMap,
1775                 SmallVectorImpl<std::pair<const char *, SubCommand *>> &Subs) {
1776   for (const auto &S : SubMap) {
1777     if (S->getName().empty())
1778       continue;
1779     Subs.push_back(std::make_pair(S->getName().data(), S));
1780   }
1781   array_pod_sort(Subs.begin(), Subs.end(), SubNameCompare);
1782 }
1783 
1784 namespace {
1785 
1786 class HelpPrinter {
1787 protected:
1788   const bool ShowHidden;
1789   typedef SmallVector<std::pair<const char *, Option *>, 128>
1790       StrOptionPairVector;
1791   typedef SmallVector<std::pair<const char *, SubCommand *>, 128>
1792       StrSubCommandPairVector;
1793   // Print the options. Opts is assumed to be alphabetically sorted.
1794   virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
1795     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1796       Opts[i].second->printOptionInfo(MaxArgLen);
1797   }
1798 
1799   void printSubCommands(StrSubCommandPairVector &Subs, size_t MaxSubLen) {
1800     for (const auto &S : Subs) {
1801       outs() << "  " << S.first;
1802       if (!S.second->getDescription().empty()) {
1803         outs().indent(MaxSubLen - strlen(S.first));
1804         outs() << " - " << S.second->getDescription();
1805       }
1806       outs() << "\n";
1807     }
1808   }
1809 
1810 public:
1811   explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {}
1812   virtual ~HelpPrinter() {}
1813 
1814   // Invoke the printer.
1815   void operator=(bool Value) {
1816     if (!Value)
1817       return;
1818     printHelp();
1819 
1820     // Halt the program since help information was printed
1821     exit(0);
1822   }
1823 
1824   void printHelp() {
1825     SubCommand *Sub = GlobalParser->getActiveSubCommand();
1826     auto &OptionsMap = Sub->OptionsMap;
1827     auto &PositionalOpts = Sub->PositionalOpts;
1828     auto &ConsumeAfterOpt = Sub->ConsumeAfterOpt;
1829 
1830     StrOptionPairVector Opts;
1831     sortOpts(OptionsMap, Opts, ShowHidden);
1832 
1833     StrSubCommandPairVector Subs;
1834     sortSubCommands(GlobalParser->RegisteredSubCommands, Subs);
1835 
1836     if (!GlobalParser->ProgramOverview.empty())
1837       outs() << "OVERVIEW: " << GlobalParser->ProgramOverview << "\n";
1838 
1839     if (Sub == &*TopLevelSubCommand) {
1840       outs() << "USAGE: " << GlobalParser->ProgramName;
1841       if (Subs.size() > 2)
1842         outs() << " [subcommand]";
1843       outs() << " [options]";
1844     } else {
1845       if (!Sub->getDescription().empty()) {
1846         outs() << "SUBCOMMAND '" << Sub->getName()
1847                << "': " << Sub->getDescription() << "\n\n";
1848       }
1849       outs() << "USAGE: " << GlobalParser->ProgramName << " " << Sub->getName()
1850              << " [options]";
1851     }
1852 
1853     for (auto Opt : PositionalOpts) {
1854       if (Opt->hasArgStr())
1855         outs() << " --" << Opt->ArgStr;
1856       outs() << " " << Opt->HelpStr;
1857     }
1858 
1859     // Print the consume after option info if it exists...
1860     if (ConsumeAfterOpt)
1861       outs() << " " << ConsumeAfterOpt->HelpStr;
1862 
1863     if (Sub == &*TopLevelSubCommand && !Subs.empty()) {
1864       // Compute the maximum subcommand length...
1865       size_t MaxSubLen = 0;
1866       for (size_t i = 0, e = Subs.size(); i != e; ++i)
1867         MaxSubLen = std::max(MaxSubLen, strlen(Subs[i].first));
1868 
1869       outs() << "\n\n";
1870       outs() << "SUBCOMMANDS:\n\n";
1871       printSubCommands(Subs, MaxSubLen);
1872       outs() << "\n";
1873       outs() << "  Type \"" << GlobalParser->ProgramName
1874              << " <subcommand> -help\" to get more help on a specific "
1875                 "subcommand";
1876     }
1877 
1878     outs() << "\n\n";
1879 
1880     // Compute the maximum argument length...
1881     size_t MaxArgLen = 0;
1882     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1883       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
1884 
1885     outs() << "OPTIONS:\n";
1886     printOptions(Opts, MaxArgLen);
1887 
1888     // Print any extra help the user has declared.
1889     for (auto I : GlobalParser->MoreHelp)
1890       outs() << I;
1891     GlobalParser->MoreHelp.clear();
1892   }
1893 };
1894 
1895 class CategorizedHelpPrinter : public HelpPrinter {
1896 public:
1897   explicit CategorizedHelpPrinter(bool showHidden) : HelpPrinter(showHidden) {}
1898 
1899   // Helper function for printOptions().
1900   // It shall return a negative value if A's name should be lexicographically
1901   // ordered before B's name. It returns a value greater than zero if B's name
1902   // should be ordered before A's name, and it returns 0 otherwise.
1903   static int OptionCategoryCompare(OptionCategory *const *A,
1904                                    OptionCategory *const *B) {
1905     return (*A)->getName().compare((*B)->getName());
1906   }
1907 
1908   // Make sure we inherit our base class's operator=()
1909   using HelpPrinter::operator=;
1910 
1911 protected:
1912   void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) override {
1913     std::vector<OptionCategory *> SortedCategories;
1914     std::map<OptionCategory *, std::vector<Option *>> CategorizedOptions;
1915 
1916     // Collect registered option categories into vector in preparation for
1917     // sorting.
1918     for (auto I = GlobalParser->RegisteredOptionCategories.begin(),
1919               E = GlobalParser->RegisteredOptionCategories.end();
1920          I != E; ++I) {
1921       SortedCategories.push_back(*I);
1922     }
1923 
1924     // Sort the different option categories alphabetically.
1925     assert(SortedCategories.size() > 0 && "No option categories registered!");
1926     array_pod_sort(SortedCategories.begin(), SortedCategories.end(),
1927                    OptionCategoryCompare);
1928 
1929     // Create map to empty vectors.
1930     for (std::vector<OptionCategory *>::const_iterator
1931              I = SortedCategories.begin(),
1932              E = SortedCategories.end();
1933          I != E; ++I)
1934       CategorizedOptions[*I] = std::vector<Option *>();
1935 
1936     // Walk through pre-sorted options and assign into categories.
1937     // Because the options are already alphabetically sorted the
1938     // options within categories will also be alphabetically sorted.
1939     for (size_t I = 0, E = Opts.size(); I != E; ++I) {
1940       Option *Opt = Opts[I].second;
1941       assert(CategorizedOptions.count(Opt->Category) > 0 &&
1942              "Option has an unregistered category");
1943       CategorizedOptions[Opt->Category].push_back(Opt);
1944     }
1945 
1946     // Now do printing.
1947     for (std::vector<OptionCategory *>::const_iterator
1948              Category = SortedCategories.begin(),
1949              E = SortedCategories.end();
1950          Category != E; ++Category) {
1951       // Hide empty categories for -help, but show for -help-hidden.
1952       const auto &CategoryOptions = CategorizedOptions[*Category];
1953       bool IsEmptyCategory = CategoryOptions.empty();
1954       if (!ShowHidden && IsEmptyCategory)
1955         continue;
1956 
1957       // Print category information.
1958       outs() << "\n";
1959       outs() << (*Category)->getName() << ":\n";
1960 
1961       // Check if description is set.
1962       if (!(*Category)->getDescription().empty())
1963         outs() << (*Category)->getDescription() << "\n\n";
1964       else
1965         outs() << "\n";
1966 
1967       // When using -help-hidden explicitly state if the category has no
1968       // options associated with it.
1969       if (IsEmptyCategory) {
1970         outs() << "  This option category has no options.\n";
1971         continue;
1972       }
1973       // Loop over the options in the category and print.
1974       for (const Option *Opt : CategoryOptions)
1975         Opt->printOptionInfo(MaxArgLen);
1976     }
1977   }
1978 };
1979 
1980 // This wraps the Uncategorizing and Categorizing printers and decides
1981 // at run time which should be invoked.
1982 class HelpPrinterWrapper {
1983 private:
1984   HelpPrinter &UncategorizedPrinter;
1985   CategorizedHelpPrinter &CategorizedPrinter;
1986 
1987 public:
1988   explicit HelpPrinterWrapper(HelpPrinter &UncategorizedPrinter,
1989                               CategorizedHelpPrinter &CategorizedPrinter)
1990       : UncategorizedPrinter(UncategorizedPrinter),
1991         CategorizedPrinter(CategorizedPrinter) {}
1992 
1993   // Invoke the printer.
1994   void operator=(bool Value);
1995 };
1996 
1997 } // End anonymous namespace
1998 
1999 // Declare the four HelpPrinter instances that are used to print out help, or
2000 // help-hidden as an uncategorized list or in categories.
2001 static HelpPrinter UncategorizedNormalPrinter(false);
2002 static HelpPrinter UncategorizedHiddenPrinter(true);
2003 static CategorizedHelpPrinter CategorizedNormalPrinter(false);
2004 static CategorizedHelpPrinter CategorizedHiddenPrinter(true);
2005 
2006 // Declare HelpPrinter wrappers that will decide whether or not to invoke
2007 // a categorizing help printer
2008 static HelpPrinterWrapper WrappedNormalPrinter(UncategorizedNormalPrinter,
2009                                                CategorizedNormalPrinter);
2010 static HelpPrinterWrapper WrappedHiddenPrinter(UncategorizedHiddenPrinter,
2011                                                CategorizedHiddenPrinter);
2012 
2013 // Define a category for generic options that all tools should have.
2014 static cl::OptionCategory GenericCategory("Generic Options");
2015 
2016 // Define uncategorized help printers.
2017 // -help-list is hidden by default because if Option categories are being used
2018 // then -help behaves the same as -help-list.
2019 static cl::opt<HelpPrinter, true, parser<bool>> HLOp(
2020     "help-list",
2021     cl::desc("Display list of available options (-help-list-hidden for more)"),
2022     cl::location(UncategorizedNormalPrinter), cl::Hidden, cl::ValueDisallowed,
2023     cl::cat(GenericCategory), cl::sub(*AllSubCommands));
2024 
2025 static cl::opt<HelpPrinter, true, parser<bool>>
2026     HLHOp("help-list-hidden", cl::desc("Display list of all available options"),
2027           cl::location(UncategorizedHiddenPrinter), cl::Hidden,
2028           cl::ValueDisallowed, cl::cat(GenericCategory),
2029           cl::sub(*AllSubCommands));
2030 
2031 // Define uncategorized/categorized help printers. These printers change their
2032 // behaviour at runtime depending on whether one or more Option categories have
2033 // been declared.
2034 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
2035     HOp("help", cl::desc("Display available options (-help-hidden for more)"),
2036         cl::location(WrappedNormalPrinter), cl::ValueDisallowed,
2037         cl::cat(GenericCategory), cl::sub(*AllSubCommands));
2038 
2039 static cl::opt<HelpPrinterWrapper, true, parser<bool>>
2040     HHOp("help-hidden", cl::desc("Display all available options"),
2041          cl::location(WrappedHiddenPrinter), cl::Hidden, cl::ValueDisallowed,
2042          cl::cat(GenericCategory), cl::sub(*AllSubCommands));
2043 
2044 static cl::opt<bool> PrintOptions(
2045     "print-options",
2046     cl::desc("Print non-default options after command line parsing"),
2047     cl::Hidden, cl::init(false), cl::cat(GenericCategory),
2048     cl::sub(*AllSubCommands));
2049 
2050 static cl::opt<bool> PrintAllOptions(
2051     "print-all-options",
2052     cl::desc("Print all option values after command line parsing"), cl::Hidden,
2053     cl::init(false), cl::cat(GenericCategory), cl::sub(*AllSubCommands));
2054 
2055 void HelpPrinterWrapper::operator=(bool Value) {
2056   if (!Value)
2057     return;
2058 
2059   // Decide which printer to invoke. If more than one option category is
2060   // registered then it is useful to show the categorized help instead of
2061   // uncategorized help.
2062   if (GlobalParser->RegisteredOptionCategories.size() > 1) {
2063     // unhide -help-list option so user can have uncategorized output if they
2064     // want it.
2065     HLOp.setHiddenFlag(NotHidden);
2066 
2067     CategorizedPrinter = true; // Invoke categorized printer
2068   } else
2069     UncategorizedPrinter = true; // Invoke uncategorized printer
2070 }
2071 
2072 // Print the value of each option.
2073 void cl::PrintOptionValues() { GlobalParser->printOptionValues(); }
2074 
2075 void CommandLineParser::printOptionValues() {
2076   if (!PrintOptions && !PrintAllOptions)
2077     return;
2078 
2079   SmallVector<std::pair<const char *, Option *>, 128> Opts;
2080   sortOpts(ActiveSubCommand->OptionsMap, Opts, /*ShowHidden*/ true);
2081 
2082   // Compute the maximum argument length...
2083   size_t MaxArgLen = 0;
2084   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2085     MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
2086 
2087   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2088     Opts[i].second->printOptionValue(MaxArgLen, PrintAllOptions);
2089 }
2090 
2091 static VersionPrinterTy OverrideVersionPrinter = nullptr;
2092 
2093 static std::vector<VersionPrinterTy> *ExtraVersionPrinters = nullptr;
2094 
2095 namespace {
2096 class VersionPrinter {
2097 public:
2098   void print() {
2099     raw_ostream &OS = outs();
2100 #ifdef PACKAGE_VENDOR
2101     OS << PACKAGE_VENDOR << " ";
2102 #else
2103     OS << "LLVM (http://llvm.org/):\n  ";
2104 #endif
2105     OS << PACKAGE_NAME << " version " << PACKAGE_VERSION;
2106 #ifdef LLVM_VERSION_INFO
2107     OS << " " << LLVM_VERSION_INFO;
2108 #endif
2109     OS << "\n  ";
2110 #ifndef __OPTIMIZE__
2111     OS << "DEBUG build";
2112 #else
2113     OS << "Optimized build";
2114 #endif
2115 #ifndef NDEBUG
2116     OS << " with assertions";
2117 #endif
2118 #if LLVM_VERSION_PRINTER_SHOW_HOST_TARGET_INFO
2119     std::string CPU = sys::getHostCPUName();
2120     if (CPU == "generic")
2121       CPU = "(unknown)";
2122     OS << ".\n"
2123        << "  Default target: " << sys::getDefaultTargetTriple() << '\n'
2124        << "  Host CPU: " << CPU;
2125 #endif
2126     OS << '\n';
2127   }
2128   void operator=(bool OptionWasSpecified) {
2129     if (!OptionWasSpecified)
2130       return;
2131 
2132     if (OverrideVersionPrinter != nullptr) {
2133       OverrideVersionPrinter(outs());
2134       exit(0);
2135     }
2136     print();
2137 
2138     // Iterate over any registered extra printers and call them to add further
2139     // information.
2140     if (ExtraVersionPrinters != nullptr) {
2141       outs() << '\n';
2142       for (auto I : *ExtraVersionPrinters)
2143         I(outs());
2144     }
2145 
2146     exit(0);
2147   }
2148 };
2149 } // End anonymous namespace
2150 
2151 // Define the --version option that prints out the LLVM version for the tool
2152 static VersionPrinter VersionPrinterInstance;
2153 
2154 static cl::opt<VersionPrinter, true, parser<bool>>
2155     VersOp("version", cl::desc("Display the version of this program"),
2156            cl::location(VersionPrinterInstance), cl::ValueDisallowed,
2157            cl::cat(GenericCategory));
2158 
2159 // Utility function for printing the help message.
2160 void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
2161   if (!Hidden && !Categorized)
2162     UncategorizedNormalPrinter.printHelp();
2163   else if (!Hidden && Categorized)
2164     CategorizedNormalPrinter.printHelp();
2165   else if (Hidden && !Categorized)
2166     UncategorizedHiddenPrinter.printHelp();
2167   else
2168     CategorizedHiddenPrinter.printHelp();
2169 }
2170 
2171 /// Utility function for printing version number.
2172 void cl::PrintVersionMessage() { VersionPrinterInstance.print(); }
2173 
2174 void cl::SetVersionPrinter(VersionPrinterTy func) { OverrideVersionPrinter = func; }
2175 
2176 void cl::AddExtraVersionPrinter(VersionPrinterTy func) {
2177   if (!ExtraVersionPrinters)
2178     ExtraVersionPrinters = new std::vector<VersionPrinterTy>;
2179 
2180   ExtraVersionPrinters->push_back(func);
2181 }
2182 
2183 StringMap<Option *> &cl::getRegisteredOptions(SubCommand &Sub) {
2184   auto &Subs = GlobalParser->RegisteredSubCommands;
2185   (void)Subs;
2186   assert(is_contained(Subs, &Sub));
2187   return Sub.OptionsMap;
2188 }
2189 
2190 iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
2191 cl::getRegisteredSubcommands() {
2192   return GlobalParser->getRegisteredSubcommands();
2193 }
2194 
2195 void cl::HideUnrelatedOptions(cl::OptionCategory &Category, SubCommand &Sub) {
2196   for (auto &I : Sub.OptionsMap) {
2197     if (I.second->Category != &Category &&
2198         I.second->Category != &GenericCategory)
2199       I.second->setHiddenFlag(cl::ReallyHidden);
2200   }
2201 }
2202 
2203 void cl::HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
2204                               SubCommand &Sub) {
2205   auto CategoriesBegin = Categories.begin();
2206   auto CategoriesEnd = Categories.end();
2207   for (auto &I : Sub.OptionsMap) {
2208     if (std::find(CategoriesBegin, CategoriesEnd, I.second->Category) ==
2209             CategoriesEnd &&
2210         I.second->Category != &GenericCategory)
2211       I.second->setHiddenFlag(cl::ReallyHidden);
2212   }
2213 }
2214 
2215 void cl::ResetCommandLineParser() { GlobalParser->reset(); }
2216 void cl::ResetAllOptionOccurrences() {
2217   GlobalParser->ResetAllOptionOccurrences();
2218 }
2219 
2220 void LLVMParseCommandLineOptions(int argc, const char *const *argv,
2221                                  const char *Overview) {
2222   llvm::cl::ParseCommandLineOptions(argc, argv, StringRef(Overview),
2223                                     &llvm::nulls());
2224 }
2225