xref: /llvm-project/llvm/lib/Support/CommandLine.cpp (revision 136e5f4850fb40b1c2be2da5e2032ab3d85a493e)
1 //===-- CommandLine.cpp - Command line parser implementation --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This class implements a command line argument processor that is useful when
10 // creating a tool.  It provides a simple, minimalistic interface that is easily
11 // extensible and supports nonlocal (library) command line options.
12 //
13 // Note that rather than trying to figure out what this code does, you could try
14 // reading the library documentation located in docs/CommandLine.html
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "llvm/Support/CommandLine.h"
19 
20 #include "DebugOptions.h"
21 
22 #include "llvm-c/Support.h"
23 #include "llvm/ADT/ArrayRef.h"
24 #include "llvm/ADT/STLFunctionalExtras.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/StringRef.h"
30 #include "llvm/ADT/Twine.h"
31 #include "llvm/Config/config.h"
32 #include "llvm/Support/ConvertUTF.h"
33 #include "llvm/Support/Debug.h"
34 #include "llvm/Support/Error.h"
35 #include "llvm/Support/ErrorHandling.h"
36 #include "llvm/Support/FileSystem.h"
37 #include "llvm/Support/ManagedStatic.h"
38 #include "llvm/Support/MemoryBuffer.h"
39 #include "llvm/Support/Path.h"
40 #include "llvm/Support/Process.h"
41 #include "llvm/Support/StringSaver.h"
42 #include "llvm/Support/VirtualFileSystem.h"
43 #include "llvm/Support/raw_ostream.h"
44 #include <cstdlib>
45 #include <optional>
46 #include <string>
47 using namespace llvm;
48 using namespace cl;
49 
50 #define DEBUG_TYPE "commandline"
51 
52 //===----------------------------------------------------------------------===//
53 // Template instantiations and anchors.
54 //
55 namespace llvm {
56 namespace cl {
57 template class basic_parser<bool>;
58 template class basic_parser<boolOrDefault>;
59 template class basic_parser<int>;
60 template class basic_parser<long>;
61 template class basic_parser<long long>;
62 template class basic_parser<unsigned>;
63 template class basic_parser<unsigned long>;
64 template class basic_parser<unsigned long long>;
65 template class basic_parser<double>;
66 template class basic_parser<float>;
67 template class basic_parser<std::string>;
68 template class basic_parser<char>;
69 
70 template class opt<unsigned>;
71 template class opt<int>;
72 template class opt<std::string>;
73 template class opt<char>;
74 template class opt<bool>;
75 } // namespace cl
76 } // namespace llvm
77 
78 // Pin the vtables to this file.
79 void GenericOptionValue::anchor() {}
80 void OptionValue<boolOrDefault>::anchor() {}
81 void OptionValue<std::string>::anchor() {}
82 void Option::anchor() {}
83 void basic_parser_impl::anchor() {}
84 void parser<bool>::anchor() {}
85 void parser<boolOrDefault>::anchor() {}
86 void parser<int>::anchor() {}
87 void parser<long>::anchor() {}
88 void parser<long long>::anchor() {}
89 void parser<unsigned>::anchor() {}
90 void parser<unsigned long>::anchor() {}
91 void parser<unsigned long long>::anchor() {}
92 void parser<double>::anchor() {}
93 void parser<float>::anchor() {}
94 void parser<std::string>::anchor() {}
95 void parser<char>::anchor() {}
96 
97 //===----------------------------------------------------------------------===//
98 
99 const static size_t DefaultPad = 2;
100 
101 static StringRef ArgPrefix = "-";
102 static StringRef ArgPrefixLong = "--";
103 static StringRef ArgHelpPrefix = " - ";
104 
105 static size_t argPlusPrefixesSize(StringRef ArgName, size_t Pad = DefaultPad) {
106   size_t Len = ArgName.size();
107   if (Len == 1)
108     return Len + Pad + ArgPrefix.size() + ArgHelpPrefix.size();
109   return Len + Pad + ArgPrefixLong.size() + ArgHelpPrefix.size();
110 }
111 
112 static SmallString<8> argPrefix(StringRef ArgName, size_t Pad = DefaultPad) {
113   SmallString<8> Prefix;
114   for (size_t I = 0; I < Pad; ++I) {
115     Prefix.push_back(' ');
116   }
117   Prefix.append(ArgName.size() > 1 ? ArgPrefixLong : ArgPrefix);
118   return Prefix;
119 }
120 
121 // Option predicates...
122 static inline bool isGrouping(const Option *O) {
123   return O->getMiscFlags() & cl::Grouping;
124 }
125 static inline bool isPrefixedOrGrouping(const Option *O) {
126   return isGrouping(O) || O->getFormattingFlag() == cl::Prefix ||
127          O->getFormattingFlag() == cl::AlwaysPrefix;
128 }
129 
130 
131 namespace {
132 
133 class PrintArg {
134   StringRef ArgName;
135   size_t Pad;
136 public:
137   PrintArg(StringRef ArgName, size_t Pad = DefaultPad) : ArgName(ArgName), Pad(Pad) {}
138   friend raw_ostream &operator<<(raw_ostream &OS, const PrintArg &);
139 };
140 
141 raw_ostream &operator<<(raw_ostream &OS, const PrintArg& Arg) {
142   OS << argPrefix(Arg.ArgName, Arg.Pad) << Arg.ArgName;
143   return OS;
144 }
145 
146 class CommandLineParser {
147 public:
148   // Globals for name and overview of program.  Program name is not a string to
149   // avoid static ctor/dtor issues.
150   std::string ProgramName;
151   StringRef ProgramOverview;
152 
153   // This collects additional help to be printed.
154   std::vector<StringRef> MoreHelp;
155 
156   // This collects Options added with the cl::DefaultOption flag. Since they can
157   // be overridden, they are not added to the appropriate SubCommands until
158   // ParseCommandLineOptions actually runs.
159   SmallVector<Option*, 4> DefaultOptions;
160 
161   // This collects the different option categories that have been registered.
162   SmallPtrSet<OptionCategory *, 16> RegisteredOptionCategories;
163 
164   // This collects the different subcommands that have been registered.
165   SmallPtrSet<SubCommand *, 4> RegisteredSubCommands;
166 
167   CommandLineParser() { registerSubCommand(&SubCommand::getTopLevel()); }
168 
169   void ResetAllOptionOccurrences();
170 
171   bool ParseCommandLineOptions(int argc, const char *const *argv,
172                                StringRef Overview, raw_ostream *Errs = nullptr,
173                                bool LongOptionsUseDoubleDash = false);
174 
175   void forEachSubCommand(Option &Opt, function_ref<void(SubCommand &)> Action) {
176     if (Opt.Subs.empty()) {
177       Action(SubCommand::getTopLevel());
178       return;
179     }
180     if (Opt.Subs.size() == 1 && *Opt.Subs.begin() == &SubCommand::getAll()) {
181       for (auto *SC : RegisteredSubCommands)
182         Action(*SC);
183       Action(SubCommand::getAll());
184       return;
185     }
186     for (auto *SC : Opt.Subs) {
187       assert(SC != &SubCommand::getAll() &&
188              "SubCommand::getAll() should not be used with other subcommands");
189       Action(*SC);
190     }
191   }
192 
193   void addLiteralOption(Option &Opt, SubCommand *SC, StringRef Name) {
194     if (Opt.hasArgStr())
195       return;
196     if (!SC->OptionsMap.insert(std::make_pair(Name, &Opt)).second) {
197       errs() << ProgramName << ": CommandLine Error: Option '" << Name
198              << "' registered more than once!\n";
199       report_fatal_error("inconsistency in registered CommandLine options");
200     }
201   }
202 
203   void addLiteralOption(Option &Opt, StringRef Name) {
204     forEachSubCommand(
205         Opt, [&](SubCommand &SC) { addLiteralOption(Opt, &SC, Name); });
206   }
207 
208   void addOption(Option *O, SubCommand *SC) {
209     bool HadErrors = false;
210     if (O->hasArgStr()) {
211       // If it's a DefaultOption, check to make sure it isn't already there.
212       if (O->isDefaultOption() && SC->OptionsMap.contains(O->ArgStr))
213         return;
214 
215       // Add argument to the argument map!
216       if (!SC->OptionsMap.insert(std::make_pair(O->ArgStr, O)).second) {
217         errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
218                << "' registered more than once!\n";
219         HadErrors = true;
220       }
221     }
222 
223     // Remember information about positional options.
224     if (O->getFormattingFlag() == cl::Positional)
225       SC->PositionalOpts.push_back(O);
226     else if (O->getMiscFlags() & cl::Sink) // Remember sink options
227       SC->SinkOpts.push_back(O);
228     else if (O->getNumOccurrencesFlag() == cl::ConsumeAfter) {
229       if (SC->ConsumeAfterOpt) {
230         O->error("Cannot specify more than one option with cl::ConsumeAfter!");
231         HadErrors = true;
232       }
233       SC->ConsumeAfterOpt = O;
234     }
235 
236     // Fail hard if there were errors. These are strictly unrecoverable and
237     // indicate serious issues such as conflicting option names or an
238     // incorrectly
239     // linked LLVM distribution.
240     if (HadErrors)
241       report_fatal_error("inconsistency in registered CommandLine options");
242   }
243 
244   void addOption(Option *O, bool ProcessDefaultOption = false) {
245     if (!ProcessDefaultOption && O->isDefaultOption()) {
246       DefaultOptions.push_back(O);
247       return;
248     }
249     forEachSubCommand(*O, [&](SubCommand &SC) { addOption(O, &SC); });
250   }
251 
252   void removeOption(Option *O, SubCommand *SC) {
253     SmallVector<StringRef, 16> OptionNames;
254     O->getExtraOptionNames(OptionNames);
255     if (O->hasArgStr())
256       OptionNames.push_back(O->ArgStr);
257 
258     SubCommand &Sub = *SC;
259     auto End = Sub.OptionsMap.end();
260     for (auto Name : OptionNames) {
261       auto I = Sub.OptionsMap.find(Name);
262       if (I != End && I->getValue() == O)
263         Sub.OptionsMap.erase(I);
264     }
265 
266     if (O->getFormattingFlag() == cl::Positional)
267       for (auto *Opt = Sub.PositionalOpts.begin();
268            Opt != Sub.PositionalOpts.end(); ++Opt) {
269         if (*Opt == O) {
270           Sub.PositionalOpts.erase(Opt);
271           break;
272         }
273       }
274     else if (O->getMiscFlags() & cl::Sink)
275       for (auto *Opt = Sub.SinkOpts.begin(); Opt != Sub.SinkOpts.end(); ++Opt) {
276         if (*Opt == O) {
277           Sub.SinkOpts.erase(Opt);
278           break;
279         }
280       }
281     else if (O == Sub.ConsumeAfterOpt)
282       Sub.ConsumeAfterOpt = nullptr;
283   }
284 
285   void removeOption(Option *O) {
286     forEachSubCommand(*O, [&](SubCommand &SC) { removeOption(O, &SC); });
287   }
288 
289   bool hasOptions(const SubCommand &Sub) const {
290     return (!Sub.OptionsMap.empty() || !Sub.PositionalOpts.empty() ||
291             nullptr != Sub.ConsumeAfterOpt);
292   }
293 
294   bool hasOptions() const {
295     for (const auto *S : RegisteredSubCommands) {
296       if (hasOptions(*S))
297         return true;
298     }
299     return false;
300   }
301 
302   bool hasNamedSubCommands() const {
303     for (const auto *S : RegisteredSubCommands)
304       if (!S->getName().empty())
305         return true;
306     return false;
307   }
308 
309   SubCommand *getActiveSubCommand() { return ActiveSubCommand; }
310 
311   void updateArgStr(Option *O, StringRef NewName, SubCommand *SC) {
312     SubCommand &Sub = *SC;
313     if (!Sub.OptionsMap.insert(std::make_pair(NewName, O)).second) {
314       errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
315              << "' registered more than once!\n";
316       report_fatal_error("inconsistency in registered CommandLine options");
317     }
318     Sub.OptionsMap.erase(O->ArgStr);
319   }
320 
321   void updateArgStr(Option *O, StringRef NewName) {
322     forEachSubCommand(*O,
323                       [&](SubCommand &SC) { updateArgStr(O, NewName, &SC); });
324   }
325 
326   void printOptionValues();
327 
328   void registerCategory(OptionCategory *cat) {
329     assert(count_if(RegisteredOptionCategories,
330                     [cat](const OptionCategory *Category) {
331              return cat->getName() == Category->getName();
332            }) == 0 &&
333            "Duplicate option categories");
334 
335     RegisteredOptionCategories.insert(cat);
336   }
337 
338   void registerSubCommand(SubCommand *sub) {
339     assert(count_if(RegisteredSubCommands,
340                     [sub](const SubCommand *Sub) {
341                       return (!sub->getName().empty()) &&
342                              (Sub->getName() == sub->getName());
343                     }) == 0 &&
344            "Duplicate subcommands");
345     RegisteredSubCommands.insert(sub);
346 
347     // For all options that have been registered for all subcommands, add the
348     // option to this subcommand now.
349     assert(sub != &SubCommand::getAll() &&
350            "SubCommand::getAll() should not be registered");
351     for (auto &E : SubCommand::getAll().OptionsMap) {
352       Option *O = E.second;
353       if ((O->isPositional() || O->isSink() || O->isConsumeAfter()) ||
354           O->hasArgStr())
355         addOption(O, sub);
356       else
357         addLiteralOption(*O, sub, E.first());
358     }
359   }
360 
361   void unregisterSubCommand(SubCommand *sub) {
362     RegisteredSubCommands.erase(sub);
363   }
364 
365   iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
366   getRegisteredSubcommands() {
367     return make_range(RegisteredSubCommands.begin(),
368                       RegisteredSubCommands.end());
369   }
370 
371   void reset() {
372     ActiveSubCommand = nullptr;
373     ProgramName.clear();
374     ProgramOverview = StringRef();
375 
376     MoreHelp.clear();
377     RegisteredOptionCategories.clear();
378 
379     ResetAllOptionOccurrences();
380     RegisteredSubCommands.clear();
381 
382     SubCommand::getTopLevel().reset();
383     SubCommand::getAll().reset();
384     registerSubCommand(&SubCommand::getTopLevel());
385 
386     DefaultOptions.clear();
387   }
388 
389 private:
390   SubCommand *ActiveSubCommand = nullptr;
391 
392   Option *LookupOption(SubCommand &Sub, StringRef &Arg, StringRef &Value);
393   Option *LookupLongOption(SubCommand &Sub, StringRef &Arg, StringRef &Value,
394                            bool LongOptionsUseDoubleDash, bool HaveDoubleDash) {
395     Option *Opt = LookupOption(Sub, Arg, Value);
396     if (Opt && LongOptionsUseDoubleDash && !HaveDoubleDash && !isGrouping(Opt))
397       return nullptr;
398     return Opt;
399   }
400   SubCommand *LookupSubCommand(StringRef Name, std::string &NearestString);
401 };
402 
403 } // namespace
404 
405 static ManagedStatic<CommandLineParser> GlobalParser;
406 
407 template <typename T, T TrueVal, T FalseVal>
408 static bool parseBool(Option &O, StringRef ArgName, StringRef Arg, T &Value) {
409   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
410       Arg == "1") {
411     Value = TrueVal;
412     return false;
413   }
414 
415   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
416     Value = FalseVal;
417     return false;
418   }
419   return O.error("'" + Arg +
420                  "' is invalid value for boolean argument! Try 0 or 1");
421 }
422 
423 void cl::AddLiteralOption(Option &O, StringRef Name) {
424   GlobalParser->addLiteralOption(O, Name);
425 }
426 
427 extrahelp::extrahelp(StringRef Help) : morehelp(Help) {
428   GlobalParser->MoreHelp.push_back(Help);
429 }
430 
431 void Option::addArgument() {
432   GlobalParser->addOption(this);
433   FullyInitialized = true;
434 }
435 
436 void Option::removeArgument() { GlobalParser->removeOption(this); }
437 
438 void Option::setArgStr(StringRef S) {
439   if (FullyInitialized)
440     GlobalParser->updateArgStr(this, S);
441   assert(!S.starts_with("-") && "Option can't start with '-");
442   ArgStr = S;
443   if (ArgStr.size() == 1)
444     setMiscFlag(Grouping);
445 }
446 
447 void Option::addCategory(OptionCategory &C) {
448   assert(!Categories.empty() && "Categories cannot be empty.");
449   // Maintain backward compatibility by replacing the default GeneralCategory
450   // if it's still set.  Otherwise, just add the new one.  The GeneralCategory
451   // must be explicitly added if you want multiple categories that include it.
452   if (&C != &getGeneralCategory() && Categories[0] == &getGeneralCategory())
453     Categories[0] = &C;
454   else if (!is_contained(Categories, &C))
455     Categories.push_back(&C);
456 }
457 
458 void Option::reset() {
459   NumOccurrences = 0;
460   setDefault();
461   if (isDefaultOption())
462     removeArgument();
463 }
464 
465 void OptionCategory::registerCategory() {
466   GlobalParser->registerCategory(this);
467 }
468 
469 // A special subcommand representing no subcommand. It is particularly important
470 // that this ManagedStatic uses constant initailization and not dynamic
471 // initialization because it is referenced from cl::opt constructors, which run
472 // dynamically in an arbitrary order.
473 LLVM_REQUIRE_CONSTANT_INITIALIZATION
474 static ManagedStatic<SubCommand> TopLevelSubCommand;
475 
476 // A special subcommand that can be used to put an option into all subcommands.
477 static ManagedStatic<SubCommand> AllSubCommands;
478 
479 SubCommand &SubCommand::getTopLevel() { return *TopLevelSubCommand; }
480 
481 SubCommand &SubCommand::getAll() { return *AllSubCommands; }
482 
483 void SubCommand::registerSubCommand() {
484   GlobalParser->registerSubCommand(this);
485 }
486 
487 void SubCommand::unregisterSubCommand() {
488   GlobalParser->unregisterSubCommand(this);
489 }
490 
491 void SubCommand::reset() {
492   PositionalOpts.clear();
493   SinkOpts.clear();
494   OptionsMap.clear();
495 
496   ConsumeAfterOpt = nullptr;
497 }
498 
499 SubCommand::operator bool() const {
500   return (GlobalParser->getActiveSubCommand() == this);
501 }
502 
503 //===----------------------------------------------------------------------===//
504 // Basic, shared command line option processing machinery.
505 //
506 
507 /// LookupOption - Lookup the option specified by the specified option on the
508 /// command line.  If there is a value specified (after an equal sign) return
509 /// that as well.  This assumes that leading dashes have already been stripped.
510 Option *CommandLineParser::LookupOption(SubCommand &Sub, StringRef &Arg,
511                                         StringRef &Value) {
512   // Reject all dashes.
513   if (Arg.empty())
514     return nullptr;
515   assert(&Sub != &SubCommand::getAll());
516 
517   size_t EqualPos = Arg.find('=');
518 
519   // If we have an equals sign, remember the value.
520   if (EqualPos == StringRef::npos) {
521     // Look up the option.
522     return Sub.OptionsMap.lookup(Arg);
523   }
524 
525   // If the argument before the = is a valid option name and the option allows
526   // non-prefix form (ie is not AlwaysPrefix), we match.  If not, signal match
527   // failure by returning nullptr.
528   auto I = Sub.OptionsMap.find(Arg.substr(0, EqualPos));
529   if (I == Sub.OptionsMap.end())
530     return nullptr;
531 
532   auto *O = I->second;
533   if (O->getFormattingFlag() == cl::AlwaysPrefix)
534     return nullptr;
535 
536   Value = Arg.substr(EqualPos + 1);
537   Arg = Arg.substr(0, EqualPos);
538   return I->second;
539 }
540 
541 SubCommand *CommandLineParser::LookupSubCommand(StringRef Name,
542                                                 std::string &NearestString) {
543   if (Name.empty())
544     return &SubCommand::getTopLevel();
545   // Find a subcommand with the edit distance == 1.
546   SubCommand *NearestMatch = nullptr;
547   for (auto *S : RegisteredSubCommands) {
548     assert(S != &SubCommand::getAll() &&
549            "SubCommand::getAll() is not expected in RegisteredSubCommands");
550     if (S->getName().empty())
551       continue;
552 
553     if (S->getName() == Name)
554       return S;
555 
556     if (!NearestMatch && S->getName().edit_distance(Name) < 2)
557       NearestMatch = S;
558   }
559 
560   if (NearestMatch)
561     NearestString = NearestMatch->getName();
562 
563   return &SubCommand::getTopLevel();
564 }
565 
566 /// LookupNearestOption - Lookup the closest match to the option specified by
567 /// the specified option on the command line.  If there is a value specified
568 /// (after an equal sign) return that as well.  This assumes that leading dashes
569 /// have already been stripped.
570 static Option *LookupNearestOption(StringRef Arg,
571                                    const StringMap<Option *> &OptionsMap,
572                                    std::string &NearestString) {
573   // Reject all dashes.
574   if (Arg.empty())
575     return nullptr;
576 
577   // Split on any equal sign.
578   std::pair<StringRef, StringRef> SplitArg = Arg.split('=');
579   StringRef &LHS = SplitArg.first; // LHS == Arg when no '=' is present.
580   StringRef &RHS = SplitArg.second;
581 
582   // Find the closest match.
583   Option *Best = nullptr;
584   unsigned BestDistance = 0;
585   for (StringMap<Option *>::const_iterator it = OptionsMap.begin(),
586                                            ie = OptionsMap.end();
587        it != ie; ++it) {
588     Option *O = it->second;
589     // Do not suggest really hidden options (not shown in any help).
590     if (O->getOptionHiddenFlag() == ReallyHidden)
591       continue;
592 
593     SmallVector<StringRef, 16> OptionNames;
594     O->getExtraOptionNames(OptionNames);
595     if (O->hasArgStr())
596       OptionNames.push_back(O->ArgStr);
597 
598     bool PermitValue = O->getValueExpectedFlag() != cl::ValueDisallowed;
599     StringRef Flag = PermitValue ? LHS : Arg;
600     for (const auto &Name : OptionNames) {
601       unsigned Distance = StringRef(Name).edit_distance(
602           Flag, /*AllowReplacements=*/true, /*MaxEditDistance=*/BestDistance);
603       if (!Best || Distance < BestDistance) {
604         Best = O;
605         BestDistance = Distance;
606         if (RHS.empty() || !PermitValue)
607           NearestString = std::string(Name);
608         else
609           NearestString = (Twine(Name) + "=" + RHS).str();
610       }
611     }
612   }
613 
614   return Best;
615 }
616 
617 /// CommaSeparateAndAddOccurrence - A wrapper around Handler->addOccurrence()
618 /// that does special handling of cl::CommaSeparated options.
619 static bool CommaSeparateAndAddOccurrence(Option *Handler, unsigned pos,
620                                           StringRef ArgName, StringRef Value,
621                                           bool MultiArg = false) {
622   // Check to see if this option accepts a comma separated list of values.  If
623   // it does, we have to split up the value into multiple values.
624   if (Handler->getMiscFlags() & CommaSeparated) {
625     StringRef Val(Value);
626     StringRef::size_type Pos = Val.find(',');
627 
628     while (Pos != StringRef::npos) {
629       // Process the portion before the comma.
630       if (Handler->addOccurrence(pos, ArgName, Val.substr(0, Pos), MultiArg))
631         return true;
632       // Erase the portion before the comma, AND the comma.
633       Val = Val.substr(Pos + 1);
634       // Check for another comma.
635       Pos = Val.find(',');
636     }
637 
638     Value = Val;
639   }
640 
641   return Handler->addOccurrence(pos, ArgName, Value, MultiArg);
642 }
643 
644 /// ProvideOption - For Value, this differentiates between an empty value ("")
645 /// and a null value (StringRef()).  The later is accepted for arguments that
646 /// don't allow a value (-foo) the former is rejected (-foo=).
647 static inline bool ProvideOption(Option *Handler, StringRef ArgName,
648                                  StringRef Value, int argc,
649                                  const char *const *argv, int &i) {
650   // Is this a multi-argument option?
651   unsigned NumAdditionalVals = Handler->getNumAdditionalVals();
652 
653   // Enforce value requirements
654   switch (Handler->getValueExpectedFlag()) {
655   case ValueRequired:
656     if (!Value.data()) { // No value specified?
657       // If no other argument or the option only supports prefix form, we
658       // cannot look at the next argument.
659       if (i + 1 >= argc || Handler->getFormattingFlag() == cl::AlwaysPrefix)
660         return Handler->error("requires a value!");
661       // Steal the next argument, like for '-o filename'
662       assert(argv && "null check");
663       Value = StringRef(argv[++i]);
664     }
665     break;
666   case ValueDisallowed:
667     if (NumAdditionalVals > 0)
668       return Handler->error("multi-valued option specified"
669                             " with ValueDisallowed modifier!");
670 
671     if (Value.data())
672       return Handler->error("does not allow a value! '" + Twine(Value) +
673                             "' specified.");
674     break;
675   case ValueOptional:
676     break;
677   }
678 
679   // If this isn't a multi-arg option, just run the handler.
680   if (NumAdditionalVals == 0)
681     return CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value);
682 
683   // If it is, run the handle several times.
684   bool MultiArg = false;
685 
686   if (Value.data()) {
687     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
688       return true;
689     --NumAdditionalVals;
690     MultiArg = true;
691   }
692 
693   while (NumAdditionalVals > 0) {
694     if (i + 1 >= argc)
695       return Handler->error("not enough values!");
696     assert(argv && "null check");
697     Value = StringRef(argv[++i]);
698 
699     if (CommaSeparateAndAddOccurrence(Handler, i, ArgName, Value, MultiArg))
700       return true;
701     MultiArg = true;
702     --NumAdditionalVals;
703   }
704   return false;
705 }
706 
707 bool llvm::cl::ProvidePositionalOption(Option *Handler, StringRef Arg, int i) {
708   int Dummy = i;
709   return ProvideOption(Handler, Handler->ArgStr, Arg, 0, nullptr, Dummy);
710 }
711 
712 // getOptionPred - Check to see if there are any options that satisfy the
713 // specified predicate with names that are the prefixes in Name.  This is
714 // checked by progressively stripping characters off of the name, checking to
715 // see if there options that satisfy the predicate.  If we find one, return it,
716 // otherwise return null.
717 //
718 static Option *getOptionPred(StringRef Name, size_t &Length,
719                              bool (*Pred)(const Option *),
720                              const StringMap<Option *> &OptionsMap) {
721   StringMap<Option *>::const_iterator OMI = OptionsMap.find(Name);
722   if (OMI != OptionsMap.end() && !Pred(OMI->getValue()))
723     OMI = OptionsMap.end();
724 
725   // Loop while we haven't found an option and Name still has at least two
726   // characters in it (so that the next iteration will not be the empty
727   // string.
728   while (OMI == OptionsMap.end() && Name.size() > 1) {
729     Name = Name.substr(0, Name.size() - 1); // Chop off the last character.
730     OMI = OptionsMap.find(Name);
731     if (OMI != OptionsMap.end() && !Pred(OMI->getValue()))
732       OMI = OptionsMap.end();
733   }
734 
735   if (OMI != OptionsMap.end() && Pred(OMI->second)) {
736     Length = Name.size();
737     return OMI->second; // Found one!
738   }
739   return nullptr; // No option found!
740 }
741 
742 /// HandlePrefixedOrGroupedOption - The specified argument string (which started
743 /// with at least one '-') does not fully match an available option.  Check to
744 /// see if this is a prefix or grouped option.  If so, split arg into output an
745 /// Arg/Value pair and return the Option to parse it with.
746 static Option *
747 HandlePrefixedOrGroupedOption(StringRef &Arg, StringRef &Value,
748                               bool &ErrorParsing,
749                               const StringMap<Option *> &OptionsMap) {
750   if (Arg.size() == 1)
751     return nullptr;
752 
753   // Do the lookup!
754   size_t Length = 0;
755   Option *PGOpt = getOptionPred(Arg, Length, isPrefixedOrGrouping, OptionsMap);
756   if (!PGOpt)
757     return nullptr;
758 
759   do {
760     StringRef MaybeValue =
761         (Length < Arg.size()) ? Arg.substr(Length) : StringRef();
762     Arg = Arg.substr(0, Length);
763     assert(OptionsMap.count(Arg) && OptionsMap.find(Arg)->second == PGOpt);
764 
765     // cl::Prefix options do not preserve '=' when used separately.
766     // The behavior for them with grouped options should be the same.
767     if (MaybeValue.empty() || PGOpt->getFormattingFlag() == cl::AlwaysPrefix ||
768         (PGOpt->getFormattingFlag() == cl::Prefix && MaybeValue[0] != '=')) {
769       Value = MaybeValue;
770       return PGOpt;
771     }
772 
773     if (MaybeValue[0] == '=') {
774       Value = MaybeValue.substr(1);
775       return PGOpt;
776     }
777 
778     // This must be a grouped option.
779     assert(isGrouping(PGOpt) && "Broken getOptionPred!");
780 
781     // Grouping options inside a group can't have values.
782     if (PGOpt->getValueExpectedFlag() == cl::ValueRequired) {
783       ErrorParsing |= PGOpt->error("may not occur within a group!");
784       return nullptr;
785     }
786 
787     // Because the value for the option is not required, we don't need to pass
788     // argc/argv in.
789     int Dummy = 0;
790     ErrorParsing |= ProvideOption(PGOpt, Arg, StringRef(), 0, nullptr, Dummy);
791 
792     // Get the next grouping option.
793     Arg = MaybeValue;
794     PGOpt = getOptionPred(Arg, Length, isGrouping, OptionsMap);
795   } while (PGOpt);
796 
797   // We could not find a grouping option in the remainder of Arg.
798   return nullptr;
799 }
800 
801 static bool RequiresValue(const Option *O) {
802   return O->getNumOccurrencesFlag() == cl::Required ||
803          O->getNumOccurrencesFlag() == cl::OneOrMore;
804 }
805 
806 static bool EatsUnboundedNumberOfValues(const Option *O) {
807   return O->getNumOccurrencesFlag() == cl::ZeroOrMore ||
808          O->getNumOccurrencesFlag() == cl::OneOrMore;
809 }
810 
811 static bool isWhitespace(char C) {
812   return C == ' ' || C == '\t' || C == '\r' || C == '\n';
813 }
814 
815 static bool isWhitespaceOrNull(char C) {
816   return isWhitespace(C) || C == '\0';
817 }
818 
819 static bool isQuote(char C) { return C == '\"' || C == '\''; }
820 
821 void cl::TokenizeGNUCommandLine(StringRef Src, StringSaver &Saver,
822                                 SmallVectorImpl<const char *> &NewArgv,
823                                 bool MarkEOLs) {
824   SmallString<128> Token;
825   for (size_t I = 0, E = Src.size(); I != E; ++I) {
826     // Consume runs of whitespace.
827     if (Token.empty()) {
828       while (I != E && isWhitespace(Src[I])) {
829         // Mark the end of lines in response files.
830         if (MarkEOLs && Src[I] == '\n')
831           NewArgv.push_back(nullptr);
832         ++I;
833       }
834       if (I == E)
835         break;
836     }
837 
838     char C = Src[I];
839 
840     // Backslash escapes the next character.
841     if (I + 1 < E && C == '\\') {
842       ++I; // Skip the escape.
843       Token.push_back(Src[I]);
844       continue;
845     }
846 
847     // Consume a quoted string.
848     if (isQuote(C)) {
849       ++I;
850       while (I != E && Src[I] != C) {
851         // Backslash escapes the next character.
852         if (Src[I] == '\\' && I + 1 != E)
853           ++I;
854         Token.push_back(Src[I]);
855         ++I;
856       }
857       if (I == E)
858         break;
859       continue;
860     }
861 
862     // End the token if this is whitespace.
863     if (isWhitespace(C)) {
864       if (!Token.empty())
865         NewArgv.push_back(Saver.save(Token.str()).data());
866       // Mark the end of lines in response files.
867       if (MarkEOLs && C == '\n')
868         NewArgv.push_back(nullptr);
869       Token.clear();
870       continue;
871     }
872 
873     // This is a normal character.  Append it.
874     Token.push_back(C);
875   }
876 
877   // Append the last token after hitting EOF with no whitespace.
878   if (!Token.empty())
879     NewArgv.push_back(Saver.save(Token.str()).data());
880 }
881 
882 /// Backslashes are interpreted in a rather complicated way in the Windows-style
883 /// command line, because backslashes are used both to separate path and to
884 /// escape double quote. This method consumes runs of backslashes as well as the
885 /// following double quote if it's escaped.
886 ///
887 ///  * If an even number of backslashes is followed by a double quote, one
888 ///    backslash is output for every pair of backslashes, and the last double
889 ///    quote remains unconsumed. The double quote will later be interpreted as
890 ///    the start or end of a quoted string in the main loop outside of this
891 ///    function.
892 ///
893 ///  * If an odd number of backslashes is followed by a double quote, one
894 ///    backslash is output for every pair of backslashes, and a double quote is
895 ///    output for the last pair of backslash-double quote. The double quote is
896 ///    consumed in this case.
897 ///
898 ///  * Otherwise, backslashes are interpreted literally.
899 static size_t parseBackslash(StringRef Src, size_t I, SmallString<128> &Token) {
900   size_t E = Src.size();
901   int BackslashCount = 0;
902   // Skip the backslashes.
903   do {
904     ++I;
905     ++BackslashCount;
906   } while (I != E && Src[I] == '\\');
907 
908   bool FollowedByDoubleQuote = (I != E && Src[I] == '"');
909   if (FollowedByDoubleQuote) {
910     Token.append(BackslashCount / 2, '\\');
911     if (BackslashCount % 2 == 0)
912       return I - 1;
913     Token.push_back('"');
914     return I;
915   }
916   Token.append(BackslashCount, '\\');
917   return I - 1;
918 }
919 
920 // Windows treats whitespace, double quotes, and backslashes specially, except
921 // when parsing the first token of a full command line, in which case
922 // backslashes are not special.
923 static bool isWindowsSpecialChar(char C) {
924   return isWhitespaceOrNull(C) || C == '\\' || C == '\"';
925 }
926 static bool isWindowsSpecialCharInCommandName(char C) {
927   return isWhitespaceOrNull(C) || C == '\"';
928 }
929 
930 // Windows tokenization implementation. The implementation is designed to be
931 // inlined and specialized for the two user entry points.
932 static inline void tokenizeWindowsCommandLineImpl(
933     StringRef Src, StringSaver &Saver, function_ref<void(StringRef)> AddToken,
934     bool AlwaysCopy, function_ref<void()> MarkEOL, bool InitialCommandName) {
935   SmallString<128> Token;
936 
937   // Sometimes, this function will be handling a full command line including an
938   // executable pathname at the start. In that situation, the initial pathname
939   // needs different handling from the following arguments, because when
940   // CreateProcess or cmd.exe scans the pathname, it doesn't treat \ as
941   // escaping the quote character, whereas when libc scans the rest of the
942   // command line, it does.
943   bool CommandName = InitialCommandName;
944 
945   // Try to do as much work inside the state machine as possible.
946   enum { INIT, UNQUOTED, QUOTED } State = INIT;
947 
948   for (size_t I = 0, E = Src.size(); I < E; ++I) {
949     switch (State) {
950     case INIT: {
951       assert(Token.empty() && "token should be empty in initial state");
952       // Eat whitespace before a token.
953       while (I < E && isWhitespaceOrNull(Src[I])) {
954         if (Src[I] == '\n')
955           MarkEOL();
956         ++I;
957       }
958       // Stop if this was trailing whitespace.
959       if (I >= E)
960         break;
961       size_t Start = I;
962       if (CommandName) {
963         while (I < E && !isWindowsSpecialCharInCommandName(Src[I]))
964           ++I;
965       } else {
966         while (I < E && !isWindowsSpecialChar(Src[I]))
967           ++I;
968       }
969       StringRef NormalChars = Src.slice(Start, I);
970       if (I >= E || isWhitespaceOrNull(Src[I])) {
971         // No special characters: slice out the substring and start the next
972         // token. Copy the string if the caller asks us to.
973         AddToken(AlwaysCopy ? Saver.save(NormalChars) : NormalChars);
974         if (I < E && Src[I] == '\n') {
975           MarkEOL();
976           CommandName = InitialCommandName;
977         } else {
978           CommandName = false;
979         }
980       } else if (Src[I] == '\"') {
981         Token += NormalChars;
982         State = QUOTED;
983       } else if (Src[I] == '\\') {
984         assert(!CommandName && "or else we'd have treated it as a normal char");
985         Token += NormalChars;
986         I = parseBackslash(Src, I, Token);
987         State = UNQUOTED;
988       } else {
989         llvm_unreachable("unexpected special character");
990       }
991       break;
992     }
993 
994     case UNQUOTED:
995       if (isWhitespaceOrNull(Src[I])) {
996         // Whitespace means the end of the token. If we are in this state, the
997         // token must have contained a special character, so we must copy the
998         // token.
999         AddToken(Saver.save(Token.str()));
1000         Token.clear();
1001         if (Src[I] == '\n') {
1002           CommandName = InitialCommandName;
1003           MarkEOL();
1004         } else {
1005           CommandName = false;
1006         }
1007         State = INIT;
1008       } else if (Src[I] == '\"') {
1009         State = QUOTED;
1010       } else if (Src[I] == '\\' && !CommandName) {
1011         I = parseBackslash(Src, I, Token);
1012       } else {
1013         Token.push_back(Src[I]);
1014       }
1015       break;
1016 
1017     case QUOTED:
1018       if (Src[I] == '\"') {
1019         if (I < (E - 1) && Src[I + 1] == '"') {
1020           // Consecutive double-quotes inside a quoted string implies one
1021           // double-quote.
1022           Token.push_back('"');
1023           ++I;
1024         } else {
1025           // Otherwise, end the quoted portion and return to the unquoted state.
1026           State = UNQUOTED;
1027         }
1028       } else if (Src[I] == '\\' && !CommandName) {
1029         I = parseBackslash(Src, I, Token);
1030       } else {
1031         Token.push_back(Src[I]);
1032       }
1033       break;
1034     }
1035   }
1036 
1037   if (State != INIT)
1038     AddToken(Saver.save(Token.str()));
1039 }
1040 
1041 void cl::TokenizeWindowsCommandLine(StringRef Src, StringSaver &Saver,
1042                                     SmallVectorImpl<const char *> &NewArgv,
1043                                     bool MarkEOLs) {
1044   auto AddToken = [&](StringRef Tok) { NewArgv.push_back(Tok.data()); };
1045   auto OnEOL = [&]() {
1046     if (MarkEOLs)
1047       NewArgv.push_back(nullptr);
1048   };
1049   tokenizeWindowsCommandLineImpl(Src, Saver, AddToken,
1050                                  /*AlwaysCopy=*/true, OnEOL, false);
1051 }
1052 
1053 void cl::TokenizeWindowsCommandLineNoCopy(StringRef Src, StringSaver &Saver,
1054                                           SmallVectorImpl<StringRef> &NewArgv) {
1055   auto AddToken = [&](StringRef Tok) { NewArgv.push_back(Tok); };
1056   auto OnEOL = []() {};
1057   tokenizeWindowsCommandLineImpl(Src, Saver, AddToken, /*AlwaysCopy=*/false,
1058                                  OnEOL, false);
1059 }
1060 
1061 void cl::TokenizeWindowsCommandLineFull(StringRef Src, StringSaver &Saver,
1062                                         SmallVectorImpl<const char *> &NewArgv,
1063                                         bool MarkEOLs) {
1064   auto AddToken = [&](StringRef Tok) { NewArgv.push_back(Tok.data()); };
1065   auto OnEOL = [&]() {
1066     if (MarkEOLs)
1067       NewArgv.push_back(nullptr);
1068   };
1069   tokenizeWindowsCommandLineImpl(Src, Saver, AddToken,
1070                                  /*AlwaysCopy=*/true, OnEOL, true);
1071 }
1072 
1073 void cl::tokenizeConfigFile(StringRef Source, StringSaver &Saver,
1074                             SmallVectorImpl<const char *> &NewArgv,
1075                             bool MarkEOLs) {
1076   for (const char *Cur = Source.begin(); Cur != Source.end();) {
1077     SmallString<128> Line;
1078     // Check for comment line.
1079     if (isWhitespace(*Cur)) {
1080       while (Cur != Source.end() && isWhitespace(*Cur))
1081         ++Cur;
1082       continue;
1083     }
1084     if (*Cur == '#') {
1085       while (Cur != Source.end() && *Cur != '\n')
1086         ++Cur;
1087       continue;
1088     }
1089     // Find end of the current line.
1090     const char *Start = Cur;
1091     for (const char *End = Source.end(); Cur != End; ++Cur) {
1092       if (*Cur == '\\') {
1093         if (Cur + 1 != End) {
1094           ++Cur;
1095           if (*Cur == '\n' ||
1096               (*Cur == '\r' && (Cur + 1 != End) && Cur[1] == '\n')) {
1097             Line.append(Start, Cur - 1);
1098             if (*Cur == '\r')
1099               ++Cur;
1100             Start = Cur + 1;
1101           }
1102         }
1103       } else if (*Cur == '\n')
1104         break;
1105     }
1106     // Tokenize line.
1107     Line.append(Start, Cur);
1108     cl::TokenizeGNUCommandLine(Line, Saver, NewArgv, MarkEOLs);
1109   }
1110 }
1111 
1112 // It is called byte order marker but the UTF-8 BOM is actually not affected
1113 // by the host system's endianness.
1114 static bool hasUTF8ByteOrderMark(ArrayRef<char> S) {
1115   return (S.size() >= 3 && S[0] == '\xef' && S[1] == '\xbb' && S[2] == '\xbf');
1116 }
1117 
1118 // Substitute <CFGDIR> with the file's base path.
1119 static void ExpandBasePaths(StringRef BasePath, StringSaver &Saver,
1120                             const char *&Arg) {
1121   assert(sys::path::is_absolute(BasePath));
1122   constexpr StringLiteral Token("<CFGDIR>");
1123   const StringRef ArgString(Arg);
1124 
1125   SmallString<128> ResponseFile;
1126   StringRef::size_type StartPos = 0;
1127   for (StringRef::size_type TokenPos = ArgString.find(Token);
1128        TokenPos != StringRef::npos;
1129        TokenPos = ArgString.find(Token, StartPos)) {
1130     // Token may appear more than once per arg (e.g. comma-separated linker
1131     // args). Support by using path-append on any subsequent appearances.
1132     const StringRef LHS = ArgString.substr(StartPos, TokenPos - StartPos);
1133     if (ResponseFile.empty())
1134       ResponseFile = LHS;
1135     else
1136       llvm::sys::path::append(ResponseFile, LHS);
1137     ResponseFile.append(BasePath);
1138     StartPos = TokenPos + Token.size();
1139   }
1140 
1141   if (!ResponseFile.empty()) {
1142     // Path-append the remaining arg substring if at least one token appeared.
1143     const StringRef Remaining = ArgString.substr(StartPos);
1144     if (!Remaining.empty())
1145       llvm::sys::path::append(ResponseFile, Remaining);
1146     Arg = Saver.save(ResponseFile.str()).data();
1147   }
1148 }
1149 
1150 // FName must be an absolute path.
1151 Error ExpansionContext::expandResponseFile(
1152     StringRef FName, SmallVectorImpl<const char *> &NewArgv) {
1153   assert(sys::path::is_absolute(FName));
1154   llvm::ErrorOr<std::unique_ptr<MemoryBuffer>> MemBufOrErr =
1155       FS->getBufferForFile(FName);
1156   if (!MemBufOrErr) {
1157     std::error_code EC = MemBufOrErr.getError();
1158     return llvm::createStringError(EC, Twine("cannot not open file '") + FName +
1159                                            "': " + EC.message());
1160   }
1161   MemoryBuffer &MemBuf = *MemBufOrErr.get();
1162   StringRef Str(MemBuf.getBufferStart(), MemBuf.getBufferSize());
1163 
1164   // If we have a UTF-16 byte order mark, convert to UTF-8 for parsing.
1165   ArrayRef<char> BufRef(MemBuf.getBufferStart(), MemBuf.getBufferEnd());
1166   std::string UTF8Buf;
1167   if (hasUTF16ByteOrderMark(BufRef)) {
1168     if (!convertUTF16ToUTF8String(BufRef, UTF8Buf))
1169       return llvm::createStringError(std::errc::illegal_byte_sequence,
1170                                      "Could not convert UTF16 to UTF8");
1171     Str = StringRef(UTF8Buf);
1172   }
1173   // If we see UTF-8 BOM sequence at the beginning of a file, we shall remove
1174   // these bytes before parsing.
1175   // Reference: http://en.wikipedia.org/wiki/UTF-8#Byte_order_mark
1176   else if (hasUTF8ByteOrderMark(BufRef))
1177     Str = StringRef(BufRef.data() + 3, BufRef.size() - 3);
1178 
1179   // Tokenize the contents into NewArgv.
1180   Tokenizer(Str, Saver, NewArgv, MarkEOLs);
1181 
1182   // Expanded file content may require additional transformations, like using
1183   // absolute paths instead of relative in '@file' constructs or expanding
1184   // macros.
1185   if (!RelativeNames && !InConfigFile)
1186     return Error::success();
1187 
1188   StringRef BasePath = llvm::sys::path::parent_path(FName);
1189   for (const char *&Arg : NewArgv) {
1190     if (!Arg)
1191       continue;
1192 
1193     // Substitute <CFGDIR> with the file's base path.
1194     if (InConfigFile)
1195       ExpandBasePaths(BasePath, Saver, Arg);
1196 
1197     // Discover the case, when argument should be transformed into '@file' and
1198     // evaluate 'file' for it.
1199     StringRef ArgStr(Arg);
1200     StringRef FileName;
1201     bool ConfigInclusion = false;
1202     if (ArgStr.consume_front("@")) {
1203       FileName = ArgStr;
1204       if (!llvm::sys::path::is_relative(FileName))
1205         continue;
1206     } else if (ArgStr.consume_front("--config=")) {
1207       FileName = ArgStr;
1208       ConfigInclusion = true;
1209     } else {
1210       continue;
1211     }
1212 
1213     // Update expansion construct.
1214     SmallString<128> ResponseFile;
1215     ResponseFile.push_back('@');
1216     if (ConfigInclusion && !llvm::sys::path::has_parent_path(FileName)) {
1217       SmallString<128> FilePath;
1218       if (!findConfigFile(FileName, FilePath))
1219         return createStringError(
1220             std::make_error_code(std::errc::no_such_file_or_directory),
1221             "cannot not find configuration file: " + FileName);
1222       ResponseFile.append(FilePath);
1223     } else {
1224       ResponseFile.append(BasePath);
1225       llvm::sys::path::append(ResponseFile, FileName);
1226     }
1227     Arg = Saver.save(ResponseFile.str()).data();
1228   }
1229   return Error::success();
1230 }
1231 
1232 /// Expand response files on a command line recursively using the given
1233 /// StringSaver and tokenization strategy.
1234 Error ExpansionContext::expandResponseFiles(
1235     SmallVectorImpl<const char *> &Argv) {
1236   struct ResponseFileRecord {
1237     std::string File;
1238     size_t End;
1239   };
1240 
1241   // To detect recursive response files, we maintain a stack of files and the
1242   // position of the last argument in the file. This position is updated
1243   // dynamically as we recursively expand files.
1244   SmallVector<ResponseFileRecord, 3> FileStack;
1245 
1246   // Push a dummy entry that represents the initial command line, removing
1247   // the need to check for an empty list.
1248   FileStack.push_back({"", Argv.size()});
1249 
1250   // Don't cache Argv.size() because it can change.
1251   for (unsigned I = 0; I != Argv.size();) {
1252     while (I == FileStack.back().End) {
1253       // Passing the end of a file's argument list, so we can remove it from the
1254       // stack.
1255       FileStack.pop_back();
1256     }
1257 
1258     const char *Arg = Argv[I];
1259     // Check if it is an EOL marker
1260     if (Arg == nullptr) {
1261       ++I;
1262       continue;
1263     }
1264 
1265     if (Arg[0] != '@') {
1266       ++I;
1267       continue;
1268     }
1269 
1270     const char *FName = Arg + 1;
1271     // Note that CurrentDir is only used for top-level rsp files, the rest will
1272     // always have an absolute path deduced from the containing file.
1273     SmallString<128> CurrDir;
1274     if (llvm::sys::path::is_relative(FName)) {
1275       if (CurrentDir.empty()) {
1276         if (auto CWD = FS->getCurrentWorkingDirectory()) {
1277           CurrDir = *CWD;
1278         } else {
1279           return createStringError(
1280               CWD.getError(), Twine("cannot get absolute path for: ") + FName);
1281         }
1282       } else {
1283         CurrDir = CurrentDir;
1284       }
1285       llvm::sys::path::append(CurrDir, FName);
1286       FName = CurrDir.c_str();
1287     }
1288 
1289     ErrorOr<llvm::vfs::Status> Res = FS->status(FName);
1290     if (!Res || !Res->exists()) {
1291       std::error_code EC = Res.getError();
1292       if (!InConfigFile) {
1293         // If the specified file does not exist, leave '@file' unexpanded, as
1294         // libiberty does.
1295         if (!EC || EC == llvm::errc::no_such_file_or_directory) {
1296           ++I;
1297           continue;
1298         }
1299       }
1300       if (!EC)
1301         EC = llvm::errc::no_such_file_or_directory;
1302       return createStringError(EC, Twine("cannot not open file '") + FName +
1303                                        "': " + EC.message());
1304     }
1305     const llvm::vfs::Status &FileStatus = Res.get();
1306 
1307     auto IsEquivalent =
1308         [FileStatus, this](const ResponseFileRecord &RFile) -> ErrorOr<bool> {
1309       ErrorOr<llvm::vfs::Status> RHS = FS->status(RFile.File);
1310       if (!RHS)
1311         return RHS.getError();
1312       return FileStatus.equivalent(*RHS);
1313     };
1314 
1315     // Check for recursive response files.
1316     for (const auto &F : drop_begin(FileStack)) {
1317       if (ErrorOr<bool> R = IsEquivalent(F)) {
1318         if (R.get())
1319           return createStringError(
1320               R.getError(), Twine("recursive expansion of: '") + F.File + "'");
1321       } else {
1322         return createStringError(R.getError(),
1323                                  Twine("cannot open file: ") + F.File);
1324       }
1325     }
1326 
1327     // Replace this response file argument with the tokenization of its
1328     // contents.  Nested response files are expanded in subsequent iterations.
1329     SmallVector<const char *, 0> ExpandedArgv;
1330     if (Error Err = expandResponseFile(FName, ExpandedArgv))
1331       return Err;
1332 
1333     for (ResponseFileRecord &Record : FileStack) {
1334       // Increase the end of all active records by the number of newly expanded
1335       // arguments, minus the response file itself.
1336       Record.End += ExpandedArgv.size() - 1;
1337     }
1338 
1339     FileStack.push_back({FName, I + ExpandedArgv.size()});
1340     Argv.erase(Argv.begin() + I);
1341     Argv.insert(Argv.begin() + I, ExpandedArgv.begin(), ExpandedArgv.end());
1342   }
1343 
1344   // If successful, the top of the file stack will mark the end of the Argv
1345   // stream. A failure here indicates a bug in the stack popping logic above.
1346   // Note that FileStack may have more than one element at this point because we
1347   // don't have a chance to pop the stack when encountering recursive files at
1348   // the end of the stream, so seeing that doesn't indicate a bug.
1349   assert(FileStack.size() > 0 && Argv.size() == FileStack.back().End);
1350   return Error::success();
1351 }
1352 
1353 bool cl::expandResponseFiles(int Argc, const char *const *Argv,
1354                              const char *EnvVar, StringSaver &Saver,
1355                              SmallVectorImpl<const char *> &NewArgv) {
1356 #ifdef _WIN32
1357   auto Tokenize = cl::TokenizeWindowsCommandLine;
1358 #else
1359   auto Tokenize = cl::TokenizeGNUCommandLine;
1360 #endif
1361   // The environment variable specifies initial options.
1362   if (EnvVar)
1363     if (std::optional<std::string> EnvValue = sys::Process::GetEnv(EnvVar))
1364       Tokenize(*EnvValue, Saver, NewArgv, /*MarkEOLs=*/false);
1365 
1366   // Command line options can override the environment variable.
1367   NewArgv.append(Argv + 1, Argv + Argc);
1368   ExpansionContext ECtx(Saver.getAllocator(), Tokenize);
1369   if (Error Err = ECtx.expandResponseFiles(NewArgv)) {
1370     errs() << toString(std::move(Err)) << '\n';
1371     return false;
1372   }
1373   return true;
1374 }
1375 
1376 bool cl::ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
1377                              SmallVectorImpl<const char *> &Argv) {
1378   ExpansionContext ECtx(Saver.getAllocator(), Tokenizer);
1379   if (Error Err = ECtx.expandResponseFiles(Argv)) {
1380     errs() << toString(std::move(Err)) << '\n';
1381     return false;
1382   }
1383   return true;
1384 }
1385 
1386 ExpansionContext::ExpansionContext(BumpPtrAllocator &A, TokenizerCallback T)
1387     : Saver(A), Tokenizer(T), FS(vfs::getRealFileSystem().get()) {}
1388 
1389 bool ExpansionContext::findConfigFile(StringRef FileName,
1390                                       SmallVectorImpl<char> &FilePath) {
1391   SmallString<128> CfgFilePath;
1392   const auto FileExists = [this](SmallString<128> Path) -> bool {
1393     auto Status = FS->status(Path);
1394     return Status &&
1395            Status->getType() == llvm::sys::fs::file_type::regular_file;
1396   };
1397 
1398   // If file name contains directory separator, treat it as a path to
1399   // configuration file.
1400   if (llvm::sys::path::has_parent_path(FileName)) {
1401     CfgFilePath = FileName;
1402     if (llvm::sys::path::is_relative(FileName) && FS->makeAbsolute(CfgFilePath))
1403       return false;
1404     if (!FileExists(CfgFilePath))
1405       return false;
1406     FilePath.assign(CfgFilePath.begin(), CfgFilePath.end());
1407     return true;
1408   }
1409 
1410   // Look for the file in search directories.
1411   for (const StringRef &Dir : SearchDirs) {
1412     if (Dir.empty())
1413       continue;
1414     CfgFilePath.assign(Dir);
1415     llvm::sys::path::append(CfgFilePath, FileName);
1416     llvm::sys::path::native(CfgFilePath);
1417     if (FileExists(CfgFilePath)) {
1418       FilePath.assign(CfgFilePath.begin(), CfgFilePath.end());
1419       return true;
1420     }
1421   }
1422 
1423   return false;
1424 }
1425 
1426 Error ExpansionContext::readConfigFile(StringRef CfgFile,
1427                                        SmallVectorImpl<const char *> &Argv) {
1428   SmallString<128> AbsPath;
1429   if (sys::path::is_relative(CfgFile)) {
1430     AbsPath.assign(CfgFile);
1431     if (std::error_code EC = FS->makeAbsolute(AbsPath))
1432       return make_error<StringError>(
1433           EC, Twine("cannot get absolute path for " + CfgFile));
1434     CfgFile = AbsPath.str();
1435   }
1436   InConfigFile = true;
1437   RelativeNames = true;
1438   if (Error Err = expandResponseFile(CfgFile, Argv))
1439     return Err;
1440   return expandResponseFiles(Argv);
1441 }
1442 
1443 static void initCommonOptions();
1444 bool cl::ParseCommandLineOptions(int argc, const char *const *argv,
1445                                  StringRef Overview, raw_ostream *Errs,
1446                                  const char *EnvVar,
1447                                  bool LongOptionsUseDoubleDash) {
1448   initCommonOptions();
1449   SmallVector<const char *, 20> NewArgv;
1450   BumpPtrAllocator A;
1451   StringSaver Saver(A);
1452   NewArgv.push_back(argv[0]);
1453 
1454   // Parse options from environment variable.
1455   if (EnvVar) {
1456     if (std::optional<std::string> EnvValue =
1457             sys::Process::GetEnv(StringRef(EnvVar)))
1458       TokenizeGNUCommandLine(*EnvValue, Saver, NewArgv);
1459   }
1460 
1461   // Append options from command line.
1462   for (int I = 1; I < argc; ++I)
1463     NewArgv.push_back(argv[I]);
1464   int NewArgc = static_cast<int>(NewArgv.size());
1465 
1466   // Parse all options.
1467   return GlobalParser->ParseCommandLineOptions(NewArgc, &NewArgv[0], Overview,
1468                                                Errs, LongOptionsUseDoubleDash);
1469 }
1470 
1471 /// Reset all options at least once, so that we can parse different options.
1472 void CommandLineParser::ResetAllOptionOccurrences() {
1473   // Reset all option values to look like they have never been seen before.
1474   // Options might be reset twice (they can be reference in both OptionsMap
1475   // and one of the other members), but that does not harm.
1476   for (auto *SC : RegisteredSubCommands) {
1477     for (auto &O : SC->OptionsMap)
1478       O.second->reset();
1479     for (Option *O : SC->PositionalOpts)
1480       O->reset();
1481     for (Option *O : SC->SinkOpts)
1482       O->reset();
1483     if (SC->ConsumeAfterOpt)
1484       SC->ConsumeAfterOpt->reset();
1485   }
1486 }
1487 
1488 bool CommandLineParser::ParseCommandLineOptions(int argc,
1489                                                 const char *const *argv,
1490                                                 StringRef Overview,
1491                                                 raw_ostream *Errs,
1492                                                 bool LongOptionsUseDoubleDash) {
1493   assert(hasOptions() && "No options specified!");
1494 
1495   ProgramOverview = Overview;
1496   bool IgnoreErrors = Errs;
1497   if (!Errs)
1498     Errs = &errs();
1499   bool ErrorParsing = false;
1500 
1501   // Expand response files.
1502   SmallVector<const char *, 20> newArgv(argv, argv + argc);
1503   BumpPtrAllocator A;
1504 #ifdef _WIN32
1505   auto Tokenize = cl::TokenizeWindowsCommandLine;
1506 #else
1507   auto Tokenize = cl::TokenizeGNUCommandLine;
1508 #endif
1509   ExpansionContext ECtx(A, Tokenize);
1510   if (Error Err = ECtx.expandResponseFiles(newArgv)) {
1511     *Errs << toString(std::move(Err)) << '\n';
1512     return false;
1513   }
1514   argv = &newArgv[0];
1515   argc = static_cast<int>(newArgv.size());
1516 
1517   // Copy the program name into ProgName, making sure not to overflow it.
1518   ProgramName = std::string(sys::path::filename(StringRef(argv[0])));
1519 
1520   // Check out the positional arguments to collect information about them.
1521   unsigned NumPositionalRequired = 0;
1522 
1523   // Determine whether or not there are an unlimited number of positionals
1524   bool HasUnlimitedPositionals = false;
1525 
1526   int FirstArg = 1;
1527   SubCommand *ChosenSubCommand = &SubCommand::getTopLevel();
1528   std::string NearestSubCommandString;
1529   bool MaybeNamedSubCommand =
1530       argc >= 2 && argv[FirstArg][0] != '-' && hasNamedSubCommands();
1531   if (MaybeNamedSubCommand) {
1532     // If the first argument specifies a valid subcommand, start processing
1533     // options from the second argument.
1534     ChosenSubCommand =
1535         LookupSubCommand(StringRef(argv[FirstArg]), NearestSubCommandString);
1536     if (ChosenSubCommand != &SubCommand::getTopLevel())
1537       FirstArg = 2;
1538   }
1539   GlobalParser->ActiveSubCommand = ChosenSubCommand;
1540 
1541   assert(ChosenSubCommand);
1542   auto &ConsumeAfterOpt = ChosenSubCommand->ConsumeAfterOpt;
1543   auto &PositionalOpts = ChosenSubCommand->PositionalOpts;
1544   auto &SinkOpts = ChosenSubCommand->SinkOpts;
1545   auto &OptionsMap = ChosenSubCommand->OptionsMap;
1546 
1547   for (auto *O: DefaultOptions) {
1548     addOption(O, true);
1549   }
1550 
1551   if (ConsumeAfterOpt) {
1552     assert(PositionalOpts.size() > 0 &&
1553            "Cannot specify cl::ConsumeAfter without a positional argument!");
1554   }
1555   if (!PositionalOpts.empty()) {
1556 
1557     // Calculate how many positional values are _required_.
1558     bool UnboundedFound = false;
1559     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
1560       Option *Opt = PositionalOpts[i];
1561       if (RequiresValue(Opt))
1562         ++NumPositionalRequired;
1563       else if (ConsumeAfterOpt) {
1564         // ConsumeAfter cannot be combined with "optional" positional options
1565         // unless there is only one positional argument...
1566         if (PositionalOpts.size() > 1) {
1567           if (!IgnoreErrors)
1568             Opt->error("error - this positional option will never be matched, "
1569                        "because it does not Require a value, and a "
1570                        "cl::ConsumeAfter option is active!");
1571           ErrorParsing = true;
1572         }
1573       } else if (UnboundedFound && !Opt->hasArgStr()) {
1574         // This option does not "require" a value...  Make sure this option is
1575         // not specified after an option that eats all extra arguments, or this
1576         // one will never get any!
1577         //
1578         if (!IgnoreErrors)
1579           Opt->error("error - option can never match, because "
1580                      "another positional argument will match an "
1581                      "unbounded number of values, and this option"
1582                      " does not require a value!");
1583         *Errs << ProgramName << ": CommandLine Error: Option '" << Opt->ArgStr
1584               << "' is all messed up!\n";
1585         *Errs << PositionalOpts.size();
1586         ErrorParsing = true;
1587       }
1588       UnboundedFound |= EatsUnboundedNumberOfValues(Opt);
1589     }
1590     HasUnlimitedPositionals = UnboundedFound || ConsumeAfterOpt;
1591   }
1592 
1593   // PositionalVals - A vector of "positional" arguments we accumulate into
1594   // the process at the end.
1595   //
1596   SmallVector<std::pair<StringRef, unsigned>, 4> PositionalVals;
1597 
1598   // If the program has named positional arguments, and the name has been run
1599   // across, keep track of which positional argument was named.  Otherwise put
1600   // the positional args into the PositionalVals list...
1601   Option *ActivePositionalArg = nullptr;
1602 
1603   // Loop over all of the arguments... processing them.
1604   bool DashDashFound = false; // Have we read '--'?
1605   for (int i = FirstArg; i < argc; ++i) {
1606     Option *Handler = nullptr;
1607     std::string NearestHandlerString;
1608     StringRef Value;
1609     StringRef ArgName = "";
1610     bool HaveDoubleDash = false;
1611 
1612     // Check to see if this is a positional argument.  This argument is
1613     // considered to be positional if it doesn't start with '-', if it is "-"
1614     // itself, or if we have seen "--" already.
1615     //
1616     if (argv[i][0] != '-' || argv[i][1] == 0 || DashDashFound) {
1617       // Positional argument!
1618       if (ActivePositionalArg) {
1619         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1620         continue; // We are done!
1621       }
1622 
1623       if (!PositionalOpts.empty()) {
1624         PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1625 
1626         // All of the positional arguments have been fulfulled, give the rest to
1627         // the consume after option... if it's specified...
1628         //
1629         if (PositionalVals.size() >= NumPositionalRequired && ConsumeAfterOpt) {
1630           for (++i; i < argc; ++i)
1631             PositionalVals.push_back(std::make_pair(StringRef(argv[i]), i));
1632           break; // Handle outside of the argument processing loop...
1633         }
1634 
1635         // Delay processing positional arguments until the end...
1636         continue;
1637       }
1638     } else if (argv[i][0] == '-' && argv[i][1] == '-' && argv[i][2] == 0 &&
1639                !DashDashFound) {
1640       DashDashFound = true; // This is the mythical "--"?
1641       continue;             // Don't try to process it as an argument itself.
1642     } else if (ActivePositionalArg &&
1643                (ActivePositionalArg->getMiscFlags() & PositionalEatsArgs)) {
1644       // If there is a positional argument eating options, check to see if this
1645       // option is another positional argument.  If so, treat it as an argument,
1646       // otherwise feed it to the eating positional.
1647       ArgName = StringRef(argv[i] + 1);
1648       // Eat second dash.
1649       if (ArgName.consume_front("-"))
1650         HaveDoubleDash = true;
1651 
1652       Handler = LookupLongOption(*ChosenSubCommand, ArgName, Value,
1653                                  LongOptionsUseDoubleDash, HaveDoubleDash);
1654       if (!Handler || Handler->getFormattingFlag() != cl::Positional) {
1655         ProvidePositionalOption(ActivePositionalArg, StringRef(argv[i]), i);
1656         continue; // We are done!
1657       }
1658     } else { // We start with a '-', must be an argument.
1659       ArgName = StringRef(argv[i] + 1);
1660       // Eat second dash.
1661       if (ArgName.consume_front("-"))
1662         HaveDoubleDash = true;
1663 
1664       Handler = LookupLongOption(*ChosenSubCommand, ArgName, Value,
1665                                  LongOptionsUseDoubleDash, HaveDoubleDash);
1666 
1667       // If Handler is not found in a specialized subcommand, look up handler
1668       // in the top-level subcommand.
1669       // cl::opt without cl::sub belongs to top-level subcommand.
1670       if (!Handler && ChosenSubCommand != &SubCommand::getTopLevel())
1671         Handler = LookupLongOption(SubCommand::getTopLevel(), ArgName, Value,
1672                                    LongOptionsUseDoubleDash, HaveDoubleDash);
1673 
1674       // Check to see if this "option" is really a prefixed or grouped argument.
1675       if (!Handler && !(LongOptionsUseDoubleDash && HaveDoubleDash))
1676         Handler = HandlePrefixedOrGroupedOption(ArgName, Value, ErrorParsing,
1677                                                 OptionsMap);
1678 
1679       // Otherwise, look for the closest available option to report to the user
1680       // in the upcoming error.
1681       if (!Handler && SinkOpts.empty())
1682         LookupNearestOption(ArgName, OptionsMap, NearestHandlerString);
1683     }
1684 
1685     if (!Handler) {
1686       if (!SinkOpts.empty()) {
1687         for (Option *SinkOpt : SinkOpts)
1688           SinkOpt->addOccurrence(i, "", StringRef(argv[i]));
1689         continue;
1690       }
1691 
1692       auto ReportUnknownArgument = [&](bool IsArg,
1693                                        StringRef NearestArgumentName) {
1694         *Errs << ProgramName << ": Unknown "
1695               << (IsArg ? "command line argument" : "subcommand") << " '"
1696               << argv[i] << "'.  Try: '" << argv[0] << " --help'\n";
1697 
1698         if (NearestArgumentName.empty())
1699           return;
1700 
1701         *Errs << ProgramName << ": Did you mean '";
1702         if (IsArg)
1703           *Errs << PrintArg(NearestArgumentName, 0);
1704         else
1705           *Errs << NearestArgumentName;
1706         *Errs << "'?\n";
1707       };
1708 
1709       if (i > 1 || !MaybeNamedSubCommand)
1710         ReportUnknownArgument(/*IsArg=*/true, NearestHandlerString);
1711       else
1712         ReportUnknownArgument(/*IsArg=*/false, NearestSubCommandString);
1713 
1714       ErrorParsing = true;
1715       continue;
1716     }
1717 
1718     // If this is a named positional argument, just remember that it is the
1719     // active one...
1720     if (Handler->getFormattingFlag() == cl::Positional) {
1721       if ((Handler->getMiscFlags() & PositionalEatsArgs) && !Value.empty()) {
1722         Handler->error("This argument does not take a value.\n"
1723                        "\tInstead, it consumes any positional arguments until "
1724                        "the next recognized option.", *Errs);
1725         ErrorParsing = true;
1726       }
1727       ActivePositionalArg = Handler;
1728     }
1729     else
1730       ErrorParsing |= ProvideOption(Handler, ArgName, Value, argc, argv, i);
1731   }
1732 
1733   // Check and handle positional arguments now...
1734   if (NumPositionalRequired > PositionalVals.size()) {
1735       *Errs << ProgramName
1736              << ": Not enough positional command line arguments specified!\n"
1737              << "Must specify at least " << NumPositionalRequired
1738              << " positional argument" << (NumPositionalRequired > 1 ? "s" : "")
1739              << ": See: " << argv[0] << " --help\n";
1740 
1741     ErrorParsing = true;
1742   } else if (!HasUnlimitedPositionals &&
1743              PositionalVals.size() > PositionalOpts.size()) {
1744     *Errs << ProgramName << ": Too many positional arguments specified!\n"
1745           << "Can specify at most " << PositionalOpts.size()
1746           << " positional arguments: See: " << argv[0] << " --help\n";
1747     ErrorParsing = true;
1748 
1749   } else if (!ConsumeAfterOpt) {
1750     // Positional args have already been handled if ConsumeAfter is specified.
1751     unsigned ValNo = 0, NumVals = static_cast<unsigned>(PositionalVals.size());
1752     for (Option *Opt : PositionalOpts) {
1753       if (RequiresValue(Opt)) {
1754         ProvidePositionalOption(Opt, PositionalVals[ValNo].first,
1755                                 PositionalVals[ValNo].second);
1756         ValNo++;
1757         --NumPositionalRequired; // We fulfilled our duty...
1758       }
1759 
1760       // If we _can_ give this option more arguments, do so now, as long as we
1761       // do not give it values that others need.  'Done' controls whether the
1762       // option even _WANTS_ any more.
1763       //
1764       bool Done = Opt->getNumOccurrencesFlag() == cl::Required;
1765       while (NumVals - ValNo > NumPositionalRequired && !Done) {
1766         switch (Opt->getNumOccurrencesFlag()) {
1767         case cl::Optional:
1768           Done = true; // Optional arguments want _at most_ one value
1769           [[fallthrough]];
1770         case cl::ZeroOrMore: // Zero or more will take all they can get...
1771         case cl::OneOrMore:  // One or more will take all they can get...
1772           ProvidePositionalOption(Opt, PositionalVals[ValNo].first,
1773                                   PositionalVals[ValNo].second);
1774           ValNo++;
1775           break;
1776         default:
1777           llvm_unreachable("Internal error, unexpected NumOccurrences flag in "
1778                            "positional argument processing!");
1779         }
1780       }
1781     }
1782   } else {
1783     assert(ConsumeAfterOpt && NumPositionalRequired <= PositionalVals.size());
1784     unsigned ValNo = 0;
1785     for (Option *Opt : PositionalOpts)
1786       if (RequiresValue(Opt)) {
1787         ErrorParsing |= ProvidePositionalOption(
1788             Opt, PositionalVals[ValNo].first, PositionalVals[ValNo].second);
1789         ValNo++;
1790       }
1791 
1792     // Handle the case where there is just one positional option, and it's
1793     // optional.  In this case, we want to give JUST THE FIRST option to the
1794     // positional option and keep the rest for the consume after.  The above
1795     // loop would have assigned no values to positional options in this case.
1796     //
1797     if (PositionalOpts.size() == 1 && ValNo == 0 && !PositionalVals.empty()) {
1798       ErrorParsing |= ProvidePositionalOption(PositionalOpts[0],
1799                                               PositionalVals[ValNo].first,
1800                                               PositionalVals[ValNo].second);
1801       ValNo++;
1802     }
1803 
1804     // Handle over all of the rest of the arguments to the
1805     // cl::ConsumeAfter command line option...
1806     for (; ValNo != PositionalVals.size(); ++ValNo)
1807       ErrorParsing |=
1808           ProvidePositionalOption(ConsumeAfterOpt, PositionalVals[ValNo].first,
1809                                   PositionalVals[ValNo].second);
1810   }
1811 
1812   // Loop over args and make sure all required args are specified!
1813   for (const auto &Opt : OptionsMap) {
1814     switch (Opt.second->getNumOccurrencesFlag()) {
1815     case Required:
1816     case OneOrMore:
1817       if (Opt.second->getNumOccurrences() == 0) {
1818         Opt.second->error("must be specified at least once!");
1819         ErrorParsing = true;
1820       }
1821       [[fallthrough]];
1822     default:
1823       break;
1824     }
1825   }
1826 
1827   // Now that we know if -debug is specified, we can use it.
1828   // Note that if ReadResponseFiles == true, this must be done before the
1829   // memory allocated for the expanded command line is free()d below.
1830   LLVM_DEBUG(dbgs() << "Args: ";
1831              for (int i = 0; i < argc; ++i) dbgs() << argv[i] << ' ';
1832              dbgs() << '\n';);
1833 
1834   // Free all of the memory allocated to the map.  Command line options may only
1835   // be processed once!
1836   MoreHelp.clear();
1837 
1838   // If we had an error processing our arguments, don't let the program execute
1839   if (ErrorParsing) {
1840     if (!IgnoreErrors)
1841       exit(1);
1842     return false;
1843   }
1844   return true;
1845 }
1846 
1847 //===----------------------------------------------------------------------===//
1848 // Option Base class implementation
1849 //
1850 
1851 bool Option::error(const Twine &Message, StringRef ArgName, raw_ostream &Errs) {
1852   if (!ArgName.data())
1853     ArgName = ArgStr;
1854   if (ArgName.empty())
1855     Errs << HelpStr; // Be nice for positional arguments
1856   else
1857     Errs << GlobalParser->ProgramName << ": for the " << PrintArg(ArgName, 0);
1858 
1859   Errs << " option: " << Message << "\n";
1860   return true;
1861 }
1862 
1863 bool Option::addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
1864                            bool MultiArg) {
1865   if (!MultiArg)
1866     NumOccurrences++; // Increment the number of times we have been seen
1867 
1868   return handleOccurrence(pos, ArgName, Value);
1869 }
1870 
1871 // getValueStr - Get the value description string, using "DefaultMsg" if nothing
1872 // has been specified yet.
1873 //
1874 static StringRef getValueStr(const Option &O, StringRef DefaultMsg) {
1875   if (O.ValueStr.empty())
1876     return DefaultMsg;
1877   return O.ValueStr;
1878 }
1879 
1880 //===----------------------------------------------------------------------===//
1881 // cl::alias class implementation
1882 //
1883 
1884 // Return the width of the option tag for printing...
1885 size_t alias::getOptionWidth() const {
1886   return argPlusPrefixesSize(ArgStr);
1887 }
1888 
1889 void Option::printHelpStr(StringRef HelpStr, size_t Indent,
1890                           size_t FirstLineIndentedBy) {
1891   assert(Indent >= FirstLineIndentedBy);
1892   std::pair<StringRef, StringRef> Split = HelpStr.split('\n');
1893   outs().indent(Indent - FirstLineIndentedBy)
1894       << ArgHelpPrefix << Split.first << "\n";
1895   while (!Split.second.empty()) {
1896     Split = Split.second.split('\n');
1897     outs().indent(Indent) << Split.first << "\n";
1898   }
1899 }
1900 
1901 void Option::printEnumValHelpStr(StringRef HelpStr, size_t BaseIndent,
1902                                  size_t FirstLineIndentedBy) {
1903   const StringRef ValHelpPrefix = "  ";
1904   assert(BaseIndent >= FirstLineIndentedBy);
1905   std::pair<StringRef, StringRef> Split = HelpStr.split('\n');
1906   outs().indent(BaseIndent - FirstLineIndentedBy)
1907       << ArgHelpPrefix << ValHelpPrefix << Split.first << "\n";
1908   while (!Split.second.empty()) {
1909     Split = Split.second.split('\n');
1910     outs().indent(BaseIndent + ValHelpPrefix.size()) << Split.first << "\n";
1911   }
1912 }
1913 
1914 // Print out the option for the alias.
1915 void alias::printOptionInfo(size_t GlobalWidth) const {
1916   outs() << PrintArg(ArgStr);
1917   printHelpStr(HelpStr, GlobalWidth, argPlusPrefixesSize(ArgStr));
1918 }
1919 
1920 //===----------------------------------------------------------------------===//
1921 // Parser Implementation code...
1922 //
1923 
1924 // basic_parser implementation
1925 //
1926 
1927 // Return the width of the option tag for printing...
1928 size_t basic_parser_impl::getOptionWidth(const Option &O) const {
1929   size_t Len = argPlusPrefixesSize(O.ArgStr);
1930   auto ValName = getValueName();
1931   if (!ValName.empty()) {
1932     size_t FormattingLen = 3;
1933     if (O.getMiscFlags() & PositionalEatsArgs)
1934       FormattingLen = 6;
1935     Len += getValueStr(O, ValName).size() + FormattingLen;
1936   }
1937 
1938   return Len;
1939 }
1940 
1941 // printOptionInfo - Print out information about this option.  The
1942 // to-be-maintained width is specified.
1943 //
1944 void basic_parser_impl::printOptionInfo(const Option &O,
1945                                         size_t GlobalWidth) const {
1946   outs() << PrintArg(O.ArgStr);
1947 
1948   auto ValName = getValueName();
1949   if (!ValName.empty()) {
1950     if (O.getMiscFlags() & PositionalEatsArgs) {
1951       outs() << " <" << getValueStr(O, ValName) << ">...";
1952     } else if (O.getValueExpectedFlag() == ValueOptional)
1953       outs() << "[=<" << getValueStr(O, ValName) << ">]";
1954     else {
1955       outs() << (O.ArgStr.size() == 1 ? " <" : "=<") << getValueStr(O, ValName)
1956              << '>';
1957     }
1958   }
1959 
1960   Option::printHelpStr(O.HelpStr, GlobalWidth, getOptionWidth(O));
1961 }
1962 
1963 void basic_parser_impl::printOptionName(const Option &O,
1964                                         size_t GlobalWidth) const {
1965   outs() << PrintArg(O.ArgStr);
1966   outs().indent(GlobalWidth - O.ArgStr.size());
1967 }
1968 
1969 // parser<bool> implementation
1970 //
1971 bool parser<bool>::parse(Option &O, StringRef ArgName, StringRef Arg,
1972                          bool &Value) {
1973   return parseBool<bool, true, false>(O, ArgName, Arg, Value);
1974 }
1975 
1976 // parser<boolOrDefault> implementation
1977 //
1978 bool parser<boolOrDefault>::parse(Option &O, StringRef ArgName, StringRef Arg,
1979                                   boolOrDefault &Value) {
1980   return parseBool<boolOrDefault, BOU_TRUE, BOU_FALSE>(O, ArgName, Arg, Value);
1981 }
1982 
1983 // parser<int> implementation
1984 //
1985 bool parser<int>::parse(Option &O, StringRef ArgName, StringRef Arg,
1986                         int &Value) {
1987   if (Arg.getAsInteger(0, Value))
1988     return O.error("'" + Arg + "' value invalid for integer argument!");
1989   return false;
1990 }
1991 
1992 // parser<long> implementation
1993 //
1994 bool parser<long>::parse(Option &O, StringRef ArgName, StringRef Arg,
1995                          long &Value) {
1996   if (Arg.getAsInteger(0, Value))
1997     return O.error("'" + Arg + "' value invalid for long argument!");
1998   return false;
1999 }
2000 
2001 // parser<long long> implementation
2002 //
2003 bool parser<long long>::parse(Option &O, StringRef ArgName, StringRef Arg,
2004                               long long &Value) {
2005   if (Arg.getAsInteger(0, Value))
2006     return O.error("'" + Arg + "' value invalid for llong argument!");
2007   return false;
2008 }
2009 
2010 // parser<unsigned> implementation
2011 //
2012 bool parser<unsigned>::parse(Option &O, StringRef ArgName, StringRef Arg,
2013                              unsigned &Value) {
2014 
2015   if (Arg.getAsInteger(0, Value))
2016     return O.error("'" + Arg + "' value invalid for uint argument!");
2017   return false;
2018 }
2019 
2020 // parser<unsigned long> implementation
2021 //
2022 bool parser<unsigned long>::parse(Option &O, StringRef ArgName, StringRef Arg,
2023                                   unsigned long &Value) {
2024 
2025   if (Arg.getAsInteger(0, Value))
2026     return O.error("'" + Arg + "' value invalid for ulong argument!");
2027   return false;
2028 }
2029 
2030 // parser<unsigned long long> implementation
2031 //
2032 bool parser<unsigned long long>::parse(Option &O, StringRef ArgName,
2033                                        StringRef Arg,
2034                                        unsigned long long &Value) {
2035 
2036   if (Arg.getAsInteger(0, Value))
2037     return O.error("'" + Arg + "' value invalid for ullong argument!");
2038   return false;
2039 }
2040 
2041 // parser<double>/parser<float> implementation
2042 //
2043 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
2044   if (to_float(Arg, Value))
2045     return false;
2046   return O.error("'" + Arg + "' value invalid for floating point argument!");
2047 }
2048 
2049 bool parser<double>::parse(Option &O, StringRef ArgName, StringRef Arg,
2050                            double &Val) {
2051   return parseDouble(O, Arg, Val);
2052 }
2053 
2054 bool parser<float>::parse(Option &O, StringRef ArgName, StringRef Arg,
2055                           float &Val) {
2056   double dVal;
2057   if (parseDouble(O, Arg, dVal))
2058     return true;
2059   Val = (float)dVal;
2060   return false;
2061 }
2062 
2063 // generic_parser_base implementation
2064 //
2065 
2066 // findOption - Return the option number corresponding to the specified
2067 // argument string.  If the option is not found, getNumOptions() is returned.
2068 //
2069 unsigned generic_parser_base::findOption(StringRef Name) {
2070   unsigned e = getNumOptions();
2071 
2072   for (unsigned i = 0; i != e; ++i) {
2073     if (getOption(i) == Name)
2074       return i;
2075   }
2076   return e;
2077 }
2078 
2079 static StringRef EqValue = "=<value>";
2080 static StringRef EmptyOption = "<empty>";
2081 static StringRef OptionPrefix = "    =";
2082 static size_t getOptionPrefixesSize() {
2083   return OptionPrefix.size() + ArgHelpPrefix.size();
2084 }
2085 
2086 static bool shouldPrintOption(StringRef Name, StringRef Description,
2087                               const Option &O) {
2088   return O.getValueExpectedFlag() != ValueOptional || !Name.empty() ||
2089          !Description.empty();
2090 }
2091 
2092 // Return the width of the option tag for printing...
2093 size_t generic_parser_base::getOptionWidth(const Option &O) const {
2094   if (O.hasArgStr()) {
2095     size_t Size =
2096         argPlusPrefixesSize(O.ArgStr) + EqValue.size();
2097     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
2098       StringRef Name = getOption(i);
2099       if (!shouldPrintOption(Name, getDescription(i), O))
2100         continue;
2101       size_t NameSize = Name.empty() ? EmptyOption.size() : Name.size();
2102       Size = std::max(Size, NameSize + getOptionPrefixesSize());
2103     }
2104     return Size;
2105   } else {
2106     size_t BaseSize = 0;
2107     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
2108       BaseSize = std::max(BaseSize, getOption(i).size() + 8);
2109     return BaseSize;
2110   }
2111 }
2112 
2113 // printOptionInfo - Print out information about this option.  The
2114 // to-be-maintained width is specified.
2115 //
2116 void generic_parser_base::printOptionInfo(const Option &O,
2117                                           size_t GlobalWidth) const {
2118   if (O.hasArgStr()) {
2119     // When the value is optional, first print a line just describing the
2120     // option without values.
2121     if (O.getValueExpectedFlag() == ValueOptional) {
2122       for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
2123         if (getOption(i).empty()) {
2124           outs() << PrintArg(O.ArgStr);
2125           Option::printHelpStr(O.HelpStr, GlobalWidth,
2126                                argPlusPrefixesSize(O.ArgStr));
2127           break;
2128         }
2129       }
2130     }
2131 
2132     outs() << PrintArg(O.ArgStr) << EqValue;
2133     Option::printHelpStr(O.HelpStr, GlobalWidth,
2134                          EqValue.size() +
2135                              argPlusPrefixesSize(O.ArgStr));
2136     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
2137       StringRef OptionName = getOption(i);
2138       StringRef Description = getDescription(i);
2139       if (!shouldPrintOption(OptionName, Description, O))
2140         continue;
2141       size_t FirstLineIndent = OptionName.size() + getOptionPrefixesSize();
2142       outs() << OptionPrefix << OptionName;
2143       if (OptionName.empty()) {
2144         outs() << EmptyOption;
2145         assert(FirstLineIndent >= EmptyOption.size());
2146         FirstLineIndent += EmptyOption.size();
2147       }
2148       if (!Description.empty())
2149         Option::printEnumValHelpStr(Description, GlobalWidth, FirstLineIndent);
2150       else
2151         outs() << '\n';
2152     }
2153   } else {
2154     if (!O.HelpStr.empty())
2155       outs() << "  " << O.HelpStr << '\n';
2156     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
2157       StringRef Option = getOption(i);
2158       outs() << "    " << PrintArg(Option);
2159       Option::printHelpStr(getDescription(i), GlobalWidth, Option.size() + 8);
2160     }
2161   }
2162 }
2163 
2164 static const size_t MaxOptWidth = 8; // arbitrary spacing for printOptionDiff
2165 
2166 // printGenericOptionDiff - Print the value of this option and it's default.
2167 //
2168 // "Generic" options have each value mapped to a name.
2169 void generic_parser_base::printGenericOptionDiff(
2170     const Option &O, const GenericOptionValue &Value,
2171     const GenericOptionValue &Default, size_t GlobalWidth) const {
2172   outs() << "  " << PrintArg(O.ArgStr);
2173   outs().indent(GlobalWidth - O.ArgStr.size());
2174 
2175   unsigned NumOpts = getNumOptions();
2176   for (unsigned i = 0; i != NumOpts; ++i) {
2177     if (!Value.compare(getOptionValue(i)))
2178       continue;
2179 
2180     outs() << "= " << getOption(i);
2181     size_t L = getOption(i).size();
2182     size_t NumSpaces = MaxOptWidth > L ? MaxOptWidth - L : 0;
2183     outs().indent(NumSpaces) << " (default: ";
2184     for (unsigned j = 0; j != NumOpts; ++j) {
2185       if (!Default.compare(getOptionValue(j)))
2186         continue;
2187       outs() << getOption(j);
2188       break;
2189     }
2190     outs() << ")\n";
2191     return;
2192   }
2193   outs() << "= *unknown option value*\n";
2194 }
2195 
2196 // printOptionDiff - Specializations for printing basic value types.
2197 //
2198 #define PRINT_OPT_DIFF(T)                                                      \
2199   void parser<T>::printOptionDiff(const Option &O, T V, OptionValue<T> D,      \
2200                                   size_t GlobalWidth) const {                  \
2201     printOptionName(O, GlobalWidth);                                           \
2202     std::string Str;                                                           \
2203     {                                                                          \
2204       raw_string_ostream SS(Str);                                              \
2205       SS << V;                                                                 \
2206     }                                                                          \
2207     outs() << "= " << Str;                                                     \
2208     size_t NumSpaces =                                                         \
2209         MaxOptWidth > Str.size() ? MaxOptWidth - Str.size() : 0;               \
2210     outs().indent(NumSpaces) << " (default: ";                                 \
2211     if (D.hasValue())                                                          \
2212       outs() << D.getValue();                                                  \
2213     else                                                                       \
2214       outs() << "*no default*";                                                \
2215     outs() << ")\n";                                                           \
2216   }
2217 
2218 PRINT_OPT_DIFF(bool)
2219 PRINT_OPT_DIFF(boolOrDefault)
2220 PRINT_OPT_DIFF(int)
2221 PRINT_OPT_DIFF(long)
2222 PRINT_OPT_DIFF(long long)
2223 PRINT_OPT_DIFF(unsigned)
2224 PRINT_OPT_DIFF(unsigned long)
2225 PRINT_OPT_DIFF(unsigned long long)
2226 PRINT_OPT_DIFF(double)
2227 PRINT_OPT_DIFF(float)
2228 PRINT_OPT_DIFF(char)
2229 
2230 void parser<std::string>::printOptionDiff(const Option &O, StringRef V,
2231                                           const OptionValue<std::string> &D,
2232                                           size_t GlobalWidth) const {
2233   printOptionName(O, GlobalWidth);
2234   outs() << "= " << V;
2235   size_t NumSpaces = MaxOptWidth > V.size() ? MaxOptWidth - V.size() : 0;
2236   outs().indent(NumSpaces) << " (default: ";
2237   if (D.hasValue())
2238     outs() << D.getValue();
2239   else
2240     outs() << "*no default*";
2241   outs() << ")\n";
2242 }
2243 
2244 // Print a placeholder for options that don't yet support printOptionDiff().
2245 void basic_parser_impl::printOptionNoValue(const Option &O,
2246                                            size_t GlobalWidth) const {
2247   printOptionName(O, GlobalWidth);
2248   outs() << "= *cannot print option value*\n";
2249 }
2250 
2251 //===----------------------------------------------------------------------===//
2252 // -help and -help-hidden option implementation
2253 //
2254 
2255 static int OptNameCompare(const std::pair<const char *, Option *> *LHS,
2256                           const std::pair<const char *, Option *> *RHS) {
2257   return strcmp(LHS->first, RHS->first);
2258 }
2259 
2260 static int SubNameCompare(const std::pair<const char *, SubCommand *> *LHS,
2261                           const std::pair<const char *, SubCommand *> *RHS) {
2262   return strcmp(LHS->first, RHS->first);
2263 }
2264 
2265 // Copy Options into a vector so we can sort them as we like.
2266 static void sortOpts(StringMap<Option *> &OptMap,
2267                      SmallVectorImpl<std::pair<const char *, Option *>> &Opts,
2268                      bool ShowHidden) {
2269   SmallPtrSet<Option *, 32> OptionSet; // Duplicate option detection.
2270 
2271   for (StringMap<Option *>::iterator I = OptMap.begin(), E = OptMap.end();
2272        I != E; ++I) {
2273     // Ignore really-hidden options.
2274     if (I->second->getOptionHiddenFlag() == ReallyHidden)
2275       continue;
2276 
2277     // Unless showhidden is set, ignore hidden flags.
2278     if (I->second->getOptionHiddenFlag() == Hidden && !ShowHidden)
2279       continue;
2280 
2281     // If we've already seen this option, don't add it to the list again.
2282     if (!OptionSet.insert(I->second).second)
2283       continue;
2284 
2285     Opts.push_back(
2286         std::pair<const char *, Option *>(I->getKey().data(), I->second));
2287   }
2288 
2289   // Sort the options list alphabetically.
2290   array_pod_sort(Opts.begin(), Opts.end(), OptNameCompare);
2291 }
2292 
2293 static void
2294 sortSubCommands(const SmallPtrSetImpl<SubCommand *> &SubMap,
2295                 SmallVectorImpl<std::pair<const char *, SubCommand *>> &Subs) {
2296   for (auto *S : SubMap) {
2297     if (S->getName().empty())
2298       continue;
2299     Subs.push_back(std::make_pair(S->getName().data(), S));
2300   }
2301   array_pod_sort(Subs.begin(), Subs.end(), SubNameCompare);
2302 }
2303 
2304 namespace {
2305 
2306 class HelpPrinter {
2307 protected:
2308   const bool ShowHidden;
2309   typedef SmallVector<std::pair<const char *, Option *>, 128>
2310       StrOptionPairVector;
2311   typedef SmallVector<std::pair<const char *, SubCommand *>, 128>
2312       StrSubCommandPairVector;
2313   // Print the options. Opts is assumed to be alphabetically sorted.
2314   virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
2315     for (size_t i = 0, e = Opts.size(); i != e; ++i)
2316       Opts[i].second->printOptionInfo(MaxArgLen);
2317   }
2318 
2319   void printSubCommands(StrSubCommandPairVector &Subs, size_t MaxSubLen) {
2320     for (const auto &S : Subs) {
2321       outs() << "  " << S.first;
2322       if (!S.second->getDescription().empty()) {
2323         outs().indent(MaxSubLen - strlen(S.first));
2324         outs() << " - " << S.second->getDescription();
2325       }
2326       outs() << "\n";
2327     }
2328   }
2329 
2330 public:
2331   explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {}
2332   virtual ~HelpPrinter() = default;
2333 
2334   // Invoke the printer.
2335   void operator=(bool Value) {
2336     if (!Value)
2337       return;
2338     printHelp();
2339 
2340     // Halt the program since help information was printed
2341     exit(0);
2342   }
2343 
2344   void printHelp() {
2345     SubCommand *Sub = GlobalParser->getActiveSubCommand();
2346     auto &OptionsMap = Sub->OptionsMap;
2347     auto &PositionalOpts = Sub->PositionalOpts;
2348     auto &ConsumeAfterOpt = Sub->ConsumeAfterOpt;
2349 
2350     StrOptionPairVector Opts;
2351     sortOpts(OptionsMap, Opts, ShowHidden);
2352 
2353     StrSubCommandPairVector Subs;
2354     sortSubCommands(GlobalParser->RegisteredSubCommands, Subs);
2355 
2356     if (!GlobalParser->ProgramOverview.empty())
2357       outs() << "OVERVIEW: " << GlobalParser->ProgramOverview << "\n";
2358 
2359     if (Sub == &SubCommand::getTopLevel()) {
2360       outs() << "USAGE: " << GlobalParser->ProgramName;
2361       if (!Subs.empty())
2362         outs() << " [subcommand]";
2363       outs() << " [options]";
2364     } else {
2365       if (!Sub->getDescription().empty()) {
2366         outs() << "SUBCOMMAND '" << Sub->getName()
2367                << "': " << Sub->getDescription() << "\n\n";
2368       }
2369       outs() << "USAGE: " << GlobalParser->ProgramName << " " << Sub->getName()
2370              << " [options]";
2371     }
2372 
2373     for (auto *Opt : PositionalOpts) {
2374       if (Opt->hasArgStr())
2375         outs() << " --" << Opt->ArgStr;
2376       outs() << " " << Opt->HelpStr;
2377     }
2378 
2379     // Print the consume after option info if it exists...
2380     if (ConsumeAfterOpt)
2381       outs() << " " << ConsumeAfterOpt->HelpStr;
2382 
2383     if (Sub == &SubCommand::getTopLevel() && !Subs.empty()) {
2384       // Compute the maximum subcommand length...
2385       size_t MaxSubLen = 0;
2386       for (size_t i = 0, e = Subs.size(); i != e; ++i)
2387         MaxSubLen = std::max(MaxSubLen, strlen(Subs[i].first));
2388 
2389       outs() << "\n\n";
2390       outs() << "SUBCOMMANDS:\n\n";
2391       printSubCommands(Subs, MaxSubLen);
2392       outs() << "\n";
2393       outs() << "  Type \"" << GlobalParser->ProgramName
2394              << " <subcommand> --help\" to get more help on a specific "
2395                 "subcommand";
2396     }
2397 
2398     outs() << "\n\n";
2399 
2400     // Compute the maximum argument length...
2401     size_t MaxArgLen = 0;
2402     for (size_t i = 0, e = Opts.size(); i != e; ++i)
2403       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
2404 
2405     outs() << "OPTIONS:\n";
2406     printOptions(Opts, MaxArgLen);
2407 
2408     // Print any extra help the user has declared.
2409     for (const auto &I : GlobalParser->MoreHelp)
2410       outs() << I;
2411     GlobalParser->MoreHelp.clear();
2412   }
2413 };
2414 
2415 class CategorizedHelpPrinter : public HelpPrinter {
2416 public:
2417   explicit CategorizedHelpPrinter(bool showHidden) : HelpPrinter(showHidden) {}
2418 
2419   // Helper function for printOptions().
2420   // It shall return a negative value if A's name should be lexicographically
2421   // ordered before B's name. It returns a value greater than zero if B's name
2422   // should be ordered before A's name, and it returns 0 otherwise.
2423   static int OptionCategoryCompare(OptionCategory *const *A,
2424                                    OptionCategory *const *B) {
2425     return (*A)->getName().compare((*B)->getName());
2426   }
2427 
2428   // Make sure we inherit our base class's operator=()
2429   using HelpPrinter::operator=;
2430 
2431 protected:
2432   void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) override {
2433     std::vector<OptionCategory *> SortedCategories;
2434     DenseMap<OptionCategory *, std::vector<Option *>> CategorizedOptions;
2435 
2436     // Collect registered option categories into vector in preparation for
2437     // sorting.
2438     for (OptionCategory *Category : GlobalParser->RegisteredOptionCategories)
2439       SortedCategories.push_back(Category);
2440 
2441     // Sort the different option categories alphabetically.
2442     assert(SortedCategories.size() > 0 && "No option categories registered!");
2443     array_pod_sort(SortedCategories.begin(), SortedCategories.end(),
2444                    OptionCategoryCompare);
2445 
2446     // Walk through pre-sorted options and assign into categories.
2447     // Because the options are already alphabetically sorted the
2448     // options within categories will also be alphabetically sorted.
2449     for (size_t I = 0, E = Opts.size(); I != E; ++I) {
2450       Option *Opt = Opts[I].second;
2451       for (auto &Cat : Opt->Categories) {
2452         assert(llvm::is_contained(SortedCategories, Cat) &&
2453                "Option has an unregistered category");
2454         CategorizedOptions[Cat].push_back(Opt);
2455       }
2456     }
2457 
2458     // Now do printing.
2459     for (OptionCategory *Category : SortedCategories) {
2460       // Hide empty categories for --help, but show for --help-hidden.
2461       const auto &CategoryOptions = CategorizedOptions[Category];
2462       if (CategoryOptions.empty())
2463         continue;
2464 
2465       // Print category information.
2466       outs() << "\n";
2467       outs() << Category->getName() << ":\n";
2468 
2469       // Check if description is set.
2470       if (!Category->getDescription().empty())
2471         outs() << Category->getDescription() << "\n\n";
2472       else
2473         outs() << "\n";
2474 
2475       // Loop over the options in the category and print.
2476       for (const Option *Opt : CategoryOptions)
2477         Opt->printOptionInfo(MaxArgLen);
2478     }
2479   }
2480 };
2481 
2482 // This wraps the Uncategorizing and Categorizing printers and decides
2483 // at run time which should be invoked.
2484 class HelpPrinterWrapper {
2485 private:
2486   HelpPrinter &UncategorizedPrinter;
2487   CategorizedHelpPrinter &CategorizedPrinter;
2488 
2489 public:
2490   explicit HelpPrinterWrapper(HelpPrinter &UncategorizedPrinter,
2491                               CategorizedHelpPrinter &CategorizedPrinter)
2492       : UncategorizedPrinter(UncategorizedPrinter),
2493         CategorizedPrinter(CategorizedPrinter) {}
2494 
2495   // Invoke the printer.
2496   void operator=(bool Value);
2497 };
2498 
2499 } // End anonymous namespace
2500 
2501 #if defined(__GNUC__)
2502 // GCC and GCC-compatible compilers define __OPTIMIZE__ when optimizations are
2503 // enabled.
2504 # if defined(__OPTIMIZE__)
2505 #  define LLVM_IS_DEBUG_BUILD 0
2506 # else
2507 #  define LLVM_IS_DEBUG_BUILD 1
2508 # endif
2509 #elif defined(_MSC_VER)
2510 // MSVC doesn't have a predefined macro indicating if optimizations are enabled.
2511 // Use _DEBUG instead. This macro actually corresponds to the choice between
2512 // debug and release CRTs, but it is a reasonable proxy.
2513 # if defined(_DEBUG)
2514 #  define LLVM_IS_DEBUG_BUILD 1
2515 # else
2516 #  define LLVM_IS_DEBUG_BUILD 0
2517 # endif
2518 #else
2519 // Otherwise, for an unknown compiler, assume this is an optimized build.
2520 # define LLVM_IS_DEBUG_BUILD 0
2521 #endif
2522 
2523 namespace {
2524 class VersionPrinter {
2525 public:
2526   void print(std::vector<VersionPrinterTy> ExtraPrinters = {}) {
2527     raw_ostream &OS = outs();
2528 #ifdef PACKAGE_VENDOR
2529     OS << PACKAGE_VENDOR << " ";
2530 #else
2531     OS << "LLVM (http://llvm.org/):\n  ";
2532 #endif
2533     OS << PACKAGE_NAME << " version " << PACKAGE_VERSION << "\n  ";
2534 #if LLVM_IS_DEBUG_BUILD
2535     OS << "DEBUG build";
2536 #else
2537     OS << "Optimized build";
2538 #endif
2539 #ifndef NDEBUG
2540     OS << " with assertions";
2541 #endif
2542     OS << ".\n";
2543 
2544     // Iterate over any registered extra printers and call them to add further
2545     // information.
2546     if (!ExtraPrinters.empty()) {
2547       for (const auto &I : ExtraPrinters)
2548         I(outs());
2549     }
2550   }
2551   void operator=(bool OptionWasSpecified);
2552 };
2553 
2554 struct CommandLineCommonOptions {
2555   // Declare the four HelpPrinter instances that are used to print out help, or
2556   // help-hidden as an uncategorized list or in categories.
2557   HelpPrinter UncategorizedNormalPrinter{false};
2558   HelpPrinter UncategorizedHiddenPrinter{true};
2559   CategorizedHelpPrinter CategorizedNormalPrinter{false};
2560   CategorizedHelpPrinter CategorizedHiddenPrinter{true};
2561   // Declare HelpPrinter wrappers that will decide whether or not to invoke
2562   // a categorizing help printer
2563   HelpPrinterWrapper WrappedNormalPrinter{UncategorizedNormalPrinter,
2564                                           CategorizedNormalPrinter};
2565   HelpPrinterWrapper WrappedHiddenPrinter{UncategorizedHiddenPrinter,
2566                                           CategorizedHiddenPrinter};
2567   // Define a category for generic options that all tools should have.
2568   cl::OptionCategory GenericCategory{"Generic Options"};
2569 
2570   // Define uncategorized help printers.
2571   // --help-list is hidden by default because if Option categories are being
2572   // used then --help behaves the same as --help-list.
2573   cl::opt<HelpPrinter, true, parser<bool>> HLOp{
2574       "help-list",
2575       cl::desc(
2576           "Display list of available options (--help-list-hidden for more)"),
2577       cl::location(UncategorizedNormalPrinter),
2578       cl::Hidden,
2579       cl::ValueDisallowed,
2580       cl::cat(GenericCategory),
2581       cl::sub(SubCommand::getAll())};
2582 
2583   cl::opt<HelpPrinter, true, parser<bool>> HLHOp{
2584       "help-list-hidden",
2585       cl::desc("Display list of all available options"),
2586       cl::location(UncategorizedHiddenPrinter),
2587       cl::Hidden,
2588       cl::ValueDisallowed,
2589       cl::cat(GenericCategory),
2590       cl::sub(SubCommand::getAll())};
2591 
2592   // Define uncategorized/categorized help printers. These printers change their
2593   // behaviour at runtime depending on whether one or more Option categories
2594   // have been declared.
2595   cl::opt<HelpPrinterWrapper, true, parser<bool>> HOp{
2596       "help",
2597       cl::desc("Display available options (--help-hidden for more)"),
2598       cl::location(WrappedNormalPrinter),
2599       cl::ValueDisallowed,
2600       cl::cat(GenericCategory),
2601       cl::sub(SubCommand::getAll())};
2602 
2603   cl::alias HOpA{"h", cl::desc("Alias for --help"), cl::aliasopt(HOp),
2604                  cl::DefaultOption};
2605 
2606   cl::opt<HelpPrinterWrapper, true, parser<bool>> HHOp{
2607       "help-hidden",
2608       cl::desc("Display all available options"),
2609       cl::location(WrappedHiddenPrinter),
2610       cl::Hidden,
2611       cl::ValueDisallowed,
2612       cl::cat(GenericCategory),
2613       cl::sub(SubCommand::getAll())};
2614 
2615   cl::opt<bool> PrintOptions{
2616       "print-options",
2617       cl::desc("Print non-default options after command line parsing"),
2618       cl::Hidden,
2619       cl::init(false),
2620       cl::cat(GenericCategory),
2621       cl::sub(SubCommand::getAll())};
2622 
2623   cl::opt<bool> PrintAllOptions{
2624       "print-all-options",
2625       cl::desc("Print all option values after command line parsing"),
2626       cl::Hidden,
2627       cl::init(false),
2628       cl::cat(GenericCategory),
2629       cl::sub(SubCommand::getAll())};
2630 
2631   VersionPrinterTy OverrideVersionPrinter = nullptr;
2632 
2633   std::vector<VersionPrinterTy> ExtraVersionPrinters;
2634 
2635   // Define the --version option that prints out the LLVM version for the tool
2636   VersionPrinter VersionPrinterInstance;
2637 
2638   cl::opt<VersionPrinter, true, parser<bool>> VersOp{
2639       "version", cl::desc("Display the version of this program"),
2640       cl::location(VersionPrinterInstance), cl::ValueDisallowed,
2641       cl::cat(GenericCategory)};
2642 };
2643 } // End anonymous namespace
2644 
2645 // Lazy-initialized global instance of options controlling the command-line
2646 // parser and general handling.
2647 static ManagedStatic<CommandLineCommonOptions> CommonOptions;
2648 
2649 static void initCommonOptions() {
2650   *CommonOptions;
2651   initDebugCounterOptions();
2652   initGraphWriterOptions();
2653   initSignalsOptions();
2654   initStatisticOptions();
2655   initTimerOptions();
2656   initTypeSizeOptions();
2657   initWithColorOptions();
2658   initDebugOptions();
2659   initRandomSeedOptions();
2660 }
2661 
2662 OptionCategory &cl::getGeneralCategory() {
2663   // Initialise the general option category.
2664   static OptionCategory GeneralCategory{"General options"};
2665   return GeneralCategory;
2666 }
2667 
2668 void VersionPrinter::operator=(bool OptionWasSpecified) {
2669   if (!OptionWasSpecified)
2670     return;
2671 
2672   if (CommonOptions->OverrideVersionPrinter != nullptr) {
2673     CommonOptions->OverrideVersionPrinter(outs());
2674     exit(0);
2675   }
2676   print(CommonOptions->ExtraVersionPrinters);
2677 
2678   exit(0);
2679 }
2680 
2681 void HelpPrinterWrapper::operator=(bool Value) {
2682   if (!Value)
2683     return;
2684 
2685   // Decide which printer to invoke. If more than one option category is
2686   // registered then it is useful to show the categorized help instead of
2687   // uncategorized help.
2688   if (GlobalParser->RegisteredOptionCategories.size() > 1) {
2689     // unhide --help-list option so user can have uncategorized output if they
2690     // want it.
2691     CommonOptions->HLOp.setHiddenFlag(NotHidden);
2692 
2693     CategorizedPrinter = true; // Invoke categorized printer
2694   } else
2695     UncategorizedPrinter = true; // Invoke uncategorized printer
2696 }
2697 
2698 // Print the value of each option.
2699 void cl::PrintOptionValues() { GlobalParser->printOptionValues(); }
2700 
2701 void CommandLineParser::printOptionValues() {
2702   if (!CommonOptions->PrintOptions && !CommonOptions->PrintAllOptions)
2703     return;
2704 
2705   SmallVector<std::pair<const char *, Option *>, 128> Opts;
2706   sortOpts(ActiveSubCommand->OptionsMap, Opts, /*ShowHidden*/ true);
2707 
2708   // Compute the maximum argument length...
2709   size_t MaxArgLen = 0;
2710   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2711     MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
2712 
2713   for (size_t i = 0, e = Opts.size(); i != e; ++i)
2714     Opts[i].second->printOptionValue(MaxArgLen, CommonOptions->PrintAllOptions);
2715 }
2716 
2717 // Utility function for printing the help message.
2718 void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
2719   if (!Hidden && !Categorized)
2720     CommonOptions->UncategorizedNormalPrinter.printHelp();
2721   else if (!Hidden && Categorized)
2722     CommonOptions->CategorizedNormalPrinter.printHelp();
2723   else if (Hidden && !Categorized)
2724     CommonOptions->UncategorizedHiddenPrinter.printHelp();
2725   else
2726     CommonOptions->CategorizedHiddenPrinter.printHelp();
2727 }
2728 
2729 ArrayRef<StringRef> cl::getCompilerBuildConfig() {
2730   static const StringRef Config[] = {
2731       // Placeholder to ensure the array always has elements, since it's an
2732       // error to have a zero-sized array. Slice this off before returning.
2733       "",
2734   // Actual compiler build config feature list:
2735 #if LLVM_IS_DEBUG_BUILD
2736       "+unoptimized",
2737 #endif
2738 #ifndef NDEBUG
2739       "+assertions",
2740 #endif
2741 #ifdef EXPENSIVE_CHECKS
2742       "+expensive-checks",
2743 #endif
2744 #if __has_feature(address_sanitizer)
2745       "+asan",
2746 #endif
2747 #if __has_feature(dataflow_sanitizer)
2748       "+dfsan",
2749 #endif
2750 #if __has_feature(hwaddress_sanitizer)
2751       "+hwasan",
2752 #endif
2753 #if __has_feature(memory_sanitizer)
2754       "+msan",
2755 #endif
2756 #if __has_feature(thread_sanitizer)
2757       "+tsan",
2758 #endif
2759 #if __has_feature(undefined_behavior_sanitizer)
2760       "+ubsan",
2761 #endif
2762   };
2763   return ArrayRef(Config).drop_front(1);
2764 }
2765 
2766 // Utility function for printing the build config.
2767 void cl::printBuildConfig(raw_ostream &OS) {
2768 #if LLVM_VERSION_PRINTER_SHOW_BUILD_CONFIG
2769   OS << "Build config: ";
2770   llvm::interleaveComma(cl::getCompilerBuildConfig(), OS);
2771   OS << '\n';
2772 #endif
2773 }
2774 
2775 /// Utility function for printing version number.
2776 void cl::PrintVersionMessage() {
2777   CommonOptions->VersionPrinterInstance.print(CommonOptions->ExtraVersionPrinters);
2778 }
2779 
2780 void cl::SetVersionPrinter(VersionPrinterTy func) {
2781   CommonOptions->OverrideVersionPrinter = func;
2782 }
2783 
2784 void cl::AddExtraVersionPrinter(VersionPrinterTy func) {
2785   CommonOptions->ExtraVersionPrinters.push_back(func);
2786 }
2787 
2788 StringMap<Option *> &cl::getRegisteredOptions(SubCommand &Sub) {
2789   initCommonOptions();
2790   auto &Subs = GlobalParser->RegisteredSubCommands;
2791   (void)Subs;
2792   assert(Subs.contains(&Sub));
2793   return Sub.OptionsMap;
2794 }
2795 
2796 iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
2797 cl::getRegisteredSubcommands() {
2798   return GlobalParser->getRegisteredSubcommands();
2799 }
2800 
2801 void cl::HideUnrelatedOptions(cl::OptionCategory &Category, SubCommand &Sub) {
2802   initCommonOptions();
2803   for (auto &I : Sub.OptionsMap) {
2804     bool Unrelated = true;
2805     for (auto &Cat : I.second->Categories) {
2806       if (Cat == &Category || Cat == &CommonOptions->GenericCategory)
2807         Unrelated = false;
2808     }
2809     if (Unrelated)
2810       I.second->setHiddenFlag(cl::ReallyHidden);
2811   }
2812 }
2813 
2814 void cl::HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
2815                               SubCommand &Sub) {
2816   initCommonOptions();
2817   for (auto &I : Sub.OptionsMap) {
2818     bool Unrelated = true;
2819     for (auto &Cat : I.second->Categories) {
2820       if (is_contained(Categories, Cat) ||
2821           Cat == &CommonOptions->GenericCategory)
2822         Unrelated = false;
2823     }
2824     if (Unrelated)
2825       I.second->setHiddenFlag(cl::ReallyHidden);
2826   }
2827 }
2828 
2829 void cl::ResetCommandLineParser() { GlobalParser->reset(); }
2830 void cl::ResetAllOptionOccurrences() {
2831   GlobalParser->ResetAllOptionOccurrences();
2832 }
2833 
2834 void LLVMParseCommandLineOptions(int argc, const char *const *argv,
2835                                  const char *Overview) {
2836   llvm::cl::ParseCommandLineOptions(argc, argv, StringRef(Overview),
2837                                     &llvm::nulls());
2838 }
2839