xref: /freebsd/contrib/llvm-project/llvm/include/llvm/Support/CommandLine.h (revision 85868e8a1daeaae7a0e48effb2ea2310ae3b02c6)
1 //===- llvm/Support/CommandLine.h - Command line handler --------*- C++ -*-===//
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 should
14 // read the library documentation located in docs/CommandLine.html or looks at
15 // the many example usages in tools/*/*.cpp
16 //
17 //===----------------------------------------------------------------------===//
18 
19 #ifndef LLVM_SUPPORT_COMMANDLINE_H
20 #define LLVM_SUPPORT_COMMANDLINE_H
21 
22 #include "llvm/ADT/ArrayRef.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/ADT/SmallPtrSet.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/StringMap.h"
27 #include "llvm/ADT/StringRef.h"
28 #include "llvm/ADT/Twine.h"
29 #include "llvm/ADT/iterator_range.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/ManagedStatic.h"
32 #include "llvm/Support/raw_ostream.h"
33 #include <cassert>
34 #include <climits>
35 #include <cstddef>
36 #include <functional>
37 #include <initializer_list>
38 #include <string>
39 #include <type_traits>
40 #include <vector>
41 
42 namespace llvm {
43 
44 class StringSaver;
45 class raw_ostream;
46 
47 /// cl Namespace - This namespace contains all of the command line option
48 /// processing machinery.  It is intentionally a short name to make qualified
49 /// usage concise.
50 namespace cl {
51 
52 //===----------------------------------------------------------------------===//
53 // ParseCommandLineOptions - Command line option processing entry point.
54 //
55 // Returns true on success. Otherwise, this will print the error message to
56 // stderr and exit if \p Errs is not set (nullptr by default), or print the
57 // error message to \p Errs and return false if \p Errs is provided.
58 //
59 // If EnvVar is not nullptr, command-line options are also parsed from the
60 // environment variable named by EnvVar.  Precedence is given to occurrences
61 // from argv.  This precedence is currently implemented by parsing argv after
62 // the environment variable, so it is only implemented correctly for options
63 // that give precedence to later occurrences.  If your program supports options
64 // that give precedence to earlier occurrences, you will need to extend this
65 // function to support it correctly.
66 bool ParseCommandLineOptions(int argc, const char *const *argv,
67                              StringRef Overview = "",
68                              raw_ostream *Errs = nullptr,
69                              const char *EnvVar = nullptr,
70                              bool LongOptionsUseDoubleDash = false);
71 
72 //===----------------------------------------------------------------------===//
73 // ParseEnvironmentOptions - Environment variable option processing alternate
74 //                           entry point.
75 //
76 void ParseEnvironmentOptions(const char *progName, const char *envvar,
77                              const char *Overview = "");
78 
79 // Function pointer type for printing version information.
80 using VersionPrinterTy = std::function<void(raw_ostream &)>;
81 
82 ///===---------------------------------------------------------------------===//
83 /// SetVersionPrinter - Override the default (LLVM specific) version printer
84 ///                     used to print out the version when --version is given
85 ///                     on the command line. This allows other systems using the
86 ///                     CommandLine utilities to print their own version string.
87 void SetVersionPrinter(VersionPrinterTy func);
88 
89 ///===---------------------------------------------------------------------===//
90 /// AddExtraVersionPrinter - Add an extra printer to use in addition to the
91 ///                          default one. This can be called multiple times,
92 ///                          and each time it adds a new function to the list
93 ///                          which will be called after the basic LLVM version
94 ///                          printing is complete. Each can then add additional
95 ///                          information specific to the tool.
96 void AddExtraVersionPrinter(VersionPrinterTy func);
97 
98 // PrintOptionValues - Print option values.
99 // With -print-options print the difference between option values and defaults.
100 // With -print-all-options print all option values.
101 // (Currently not perfect, but best-effort.)
102 void PrintOptionValues();
103 
104 // Forward declaration - AddLiteralOption needs to be up here to make gcc happy.
105 class Option;
106 
107 /// Adds a new option for parsing and provides the option it refers to.
108 ///
109 /// \param O pointer to the option
110 /// \param Name the string name for the option to handle during parsing
111 ///
112 /// Literal options are used by some parsers to register special option values.
113 /// This is how the PassNameParser registers pass names for opt.
114 void AddLiteralOption(Option &O, StringRef Name);
115 
116 //===----------------------------------------------------------------------===//
117 // Flags permitted to be passed to command line arguments
118 //
119 
120 enum NumOccurrencesFlag { // Flags for the number of occurrences allowed
121   Optional = 0x00,        // Zero or One occurrence
122   ZeroOrMore = 0x01,      // Zero or more occurrences allowed
123   Required = 0x02,        // One occurrence required
124   OneOrMore = 0x03,       // One or more occurrences required
125 
126   // ConsumeAfter - Indicates that this option is fed anything that follows the
127   // last positional argument required by the application (it is an error if
128   // there are zero positional arguments, and a ConsumeAfter option is used).
129   // Thus, for example, all arguments to LLI are processed until a filename is
130   // found.  Once a filename is found, all of the succeeding arguments are
131   // passed, unprocessed, to the ConsumeAfter option.
132   //
133   ConsumeAfter = 0x04
134 };
135 
136 enum ValueExpected { // Is a value required for the option?
137   // zero reserved for the unspecified value
138   ValueOptional = 0x01,  // The value can appear... or not
139   ValueRequired = 0x02,  // The value is required to appear!
140   ValueDisallowed = 0x03 // A value may not be specified (for flags)
141 };
142 
143 enum OptionHidden {   // Control whether -help shows this option
144   NotHidden = 0x00,   // Option included in -help & -help-hidden
145   Hidden = 0x01,      // -help doesn't, but -help-hidden does
146   ReallyHidden = 0x02 // Neither -help nor -help-hidden show this arg
147 };
148 
149 // Formatting flags - This controls special features that the option might have
150 // that cause it to be parsed differently...
151 //
152 // Prefix - This option allows arguments that are otherwise unrecognized to be
153 // matched by options that are a prefix of the actual value.  This is useful for
154 // cases like a linker, where options are typically of the form '-lfoo' or
155 // '-L../../include' where -l or -L are the actual flags.  When prefix is
156 // enabled, and used, the value for the flag comes from the suffix of the
157 // argument.
158 //
159 // AlwaysPrefix - Only allow the behavior enabled by the Prefix flag and reject
160 // the Option=Value form.
161 //
162 
163 enum FormattingFlags {
164   NormalFormatting = 0x00, // Nothing special
165   Positional = 0x01,       // Is a positional argument, no '-' required
166   Prefix = 0x02,           // Can this option directly prefix its value?
167   AlwaysPrefix = 0x03      // Can this option only directly prefix its value?
168 };
169 
170 enum MiscFlags {             // Miscellaneous flags to adjust argument
171   CommaSeparated = 0x01,     // Should this cl::list split between commas?
172   PositionalEatsArgs = 0x02, // Should this positional cl::list eat -args?
173   Sink = 0x04,               // Should this cl::list eat all unknown options?
174 
175   // Grouping - Can this option group with other options?
176   // If this is enabled, multiple letter options are allowed to bunch together
177   // with only a single hyphen for the whole group.  This allows emulation
178   // of the behavior that ls uses for example: ls -la === ls -l -a
179   Grouping = 0x08,
180 
181   // Default option
182   DefaultOption = 0x10
183 };
184 
185 //===----------------------------------------------------------------------===//
186 // Option Category class
187 //
188 class OptionCategory {
189 private:
190   StringRef const Name;
191   StringRef const Description;
192 
193   void registerCategory();
194 
195 public:
196   OptionCategory(StringRef const Name,
197                  StringRef const Description = "")
198       : Name(Name), Description(Description) {
199     registerCategory();
200   }
201 
202   StringRef getName() const { return Name; }
203   StringRef getDescription() const { return Description; }
204 };
205 
206 // The general Option Category (used as default category).
207 extern OptionCategory GeneralCategory;
208 
209 //===----------------------------------------------------------------------===//
210 // SubCommand class
211 //
212 class SubCommand {
213 private:
214   StringRef Name;
215   StringRef Description;
216 
217 protected:
218   void registerSubCommand();
219   void unregisterSubCommand();
220 
221 public:
222   SubCommand(StringRef Name, StringRef Description = "")
223       : Name(Name), Description(Description) {
224         registerSubCommand();
225   }
226   SubCommand() = default;
227 
228   void reset();
229 
230   explicit operator bool() const;
231 
232   StringRef getName() const { return Name; }
233   StringRef getDescription() const { return Description; }
234 
235   SmallVector<Option *, 4> PositionalOpts;
236   SmallVector<Option *, 4> SinkOpts;
237   StringMap<Option *> OptionsMap;
238 
239   Option *ConsumeAfterOpt = nullptr; // The ConsumeAfter option if it exists.
240 };
241 
242 // A special subcommand representing no subcommand
243 extern ManagedStatic<SubCommand> TopLevelSubCommand;
244 
245 // A special subcommand that can be used to put an option into all subcommands.
246 extern ManagedStatic<SubCommand> AllSubCommands;
247 
248 //===----------------------------------------------------------------------===//
249 // Option Base class
250 //
251 class Option {
252   friend class alias;
253 
254   // handleOccurrences - Overriden by subclasses to handle the value passed into
255   // an argument.  Should return true if there was an error processing the
256   // argument and the program should exit.
257   //
258   virtual bool handleOccurrence(unsigned pos, StringRef ArgName,
259                                 StringRef Arg) = 0;
260 
261   virtual enum ValueExpected getValueExpectedFlagDefault() const {
262     return ValueOptional;
263   }
264 
265   // Out of line virtual function to provide home for the class.
266   virtual void anchor();
267 
268   uint16_t NumOccurrences; // The number of times specified
269   // Occurrences, HiddenFlag, and Formatting are all enum types but to avoid
270   // problems with signed enums in bitfields.
271   uint16_t Occurrences : 3; // enum NumOccurrencesFlag
272   // not using the enum type for 'Value' because zero is an implementation
273   // detail representing the non-value
274   uint16_t Value : 2;
275   uint16_t HiddenFlag : 2; // enum OptionHidden
276   uint16_t Formatting : 2; // enum FormattingFlags
277   uint16_t Misc : 5;
278   uint16_t FullyInitialized : 1; // Has addArgument been called?
279   uint16_t Position;             // Position of last occurrence of the option
280   uint16_t AdditionalVals;       // Greater than 0 for multi-valued option.
281 
282 public:
283   StringRef ArgStr;   // The argument string itself (ex: "help", "o")
284   StringRef HelpStr;  // The descriptive text message for -help
285   StringRef ValueStr; // String describing what the value of this option is
286   SmallVector<OptionCategory *, 1>
287       Categories;                    // The Categories this option belongs to
288   SmallPtrSet<SubCommand *, 1> Subs; // The subcommands this option belongs to.
289 
290   inline enum NumOccurrencesFlag getNumOccurrencesFlag() const {
291     return (enum NumOccurrencesFlag)Occurrences;
292   }
293 
294   inline enum ValueExpected getValueExpectedFlag() const {
295     return Value ? ((enum ValueExpected)Value) : getValueExpectedFlagDefault();
296   }
297 
298   inline enum OptionHidden getOptionHiddenFlag() const {
299     return (enum OptionHidden)HiddenFlag;
300   }
301 
302   inline enum FormattingFlags getFormattingFlag() const {
303     return (enum FormattingFlags)Formatting;
304   }
305 
306   inline unsigned getMiscFlags() const { return Misc; }
307   inline unsigned getPosition() const { return Position; }
308   inline unsigned getNumAdditionalVals() const { return AdditionalVals; }
309 
310   // hasArgStr - Return true if the argstr != ""
311   bool hasArgStr() const { return !ArgStr.empty(); }
312   bool isPositional() const { return getFormattingFlag() == cl::Positional; }
313   bool isSink() const { return getMiscFlags() & cl::Sink; }
314   bool isDefaultOption() const { return getMiscFlags() & cl::DefaultOption; }
315 
316   bool isConsumeAfter() const {
317     return getNumOccurrencesFlag() == cl::ConsumeAfter;
318   }
319 
320   bool isInAllSubCommands() const {
321     return any_of(Subs, [](const SubCommand *SC) {
322       return SC == &*AllSubCommands;
323     });
324   }
325 
326   //-------------------------------------------------------------------------===
327   // Accessor functions set by OptionModifiers
328   //
329   void setArgStr(StringRef S);
330   void setDescription(StringRef S) { HelpStr = S; }
331   void setValueStr(StringRef S) { ValueStr = S; }
332   void setNumOccurrencesFlag(enum NumOccurrencesFlag Val) { Occurrences = Val; }
333   void setValueExpectedFlag(enum ValueExpected Val) { Value = Val; }
334   void setHiddenFlag(enum OptionHidden Val) { HiddenFlag = Val; }
335   void setFormattingFlag(enum FormattingFlags V) { Formatting = V; }
336   void setMiscFlag(enum MiscFlags M) { Misc |= M; }
337   void setPosition(unsigned pos) { Position = pos; }
338   void addCategory(OptionCategory &C);
339   void addSubCommand(SubCommand &S) { Subs.insert(&S); }
340 
341 protected:
342   explicit Option(enum NumOccurrencesFlag OccurrencesFlag,
343                   enum OptionHidden Hidden)
344       : NumOccurrences(0), Occurrences(OccurrencesFlag), Value(0),
345         HiddenFlag(Hidden), Formatting(NormalFormatting), Misc(0),
346         FullyInitialized(false), Position(0), AdditionalVals(0) {
347     Categories.push_back(&GeneralCategory);
348   }
349 
350   inline void setNumAdditionalVals(unsigned n) { AdditionalVals = n; }
351 
352 public:
353   virtual ~Option() = default;
354 
355   // addArgument - Register this argument with the commandline system.
356   //
357   void addArgument();
358 
359   /// Unregisters this option from the CommandLine system.
360   ///
361   /// This option must have been the last option registered.
362   /// For testing purposes only.
363   void removeArgument();
364 
365   // Return the width of the option tag for printing...
366   virtual size_t getOptionWidth() const = 0;
367 
368   // printOptionInfo - Print out information about this option.  The
369   // to-be-maintained width is specified.
370   //
371   virtual void printOptionInfo(size_t GlobalWidth) const = 0;
372 
373   virtual void printOptionValue(size_t GlobalWidth, bool Force) const = 0;
374 
375   virtual void setDefault() = 0;
376 
377   static void printHelpStr(StringRef HelpStr, size_t Indent,
378                            size_t FirstLineIndentedBy);
379 
380   virtual void getExtraOptionNames(SmallVectorImpl<StringRef> &) {}
381 
382   // addOccurrence - Wrapper around handleOccurrence that enforces Flags.
383   //
384   virtual bool addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
385                              bool MultiArg = false);
386 
387   // Prints option name followed by message.  Always returns true.
388   bool error(const Twine &Message, StringRef ArgName = StringRef(), raw_ostream &Errs = llvm::errs());
389   bool error(const Twine &Message, raw_ostream &Errs) {
390     return error(Message, StringRef(), Errs);
391   }
392 
393   inline int getNumOccurrences() const { return NumOccurrences; }
394   void reset();
395 };
396 
397 //===----------------------------------------------------------------------===//
398 // Command line option modifiers that can be used to modify the behavior of
399 // command line option parsers...
400 //
401 
402 // desc - Modifier to set the description shown in the -help output...
403 struct desc {
404   StringRef Desc;
405 
406   desc(StringRef Str) : Desc(Str) {}
407 
408   void apply(Option &O) const { O.setDescription(Desc); }
409 };
410 
411 // value_desc - Modifier to set the value description shown in the -help
412 // output...
413 struct value_desc {
414   StringRef Desc;
415 
416   value_desc(StringRef Str) : Desc(Str) {}
417 
418   void apply(Option &O) const { O.setValueStr(Desc); }
419 };
420 
421 // init - Specify a default (initial) value for the command line argument, if
422 // the default constructor for the argument type does not give you what you
423 // want.  This is only valid on "opt" arguments, not on "list" arguments.
424 //
425 template <class Ty> struct initializer {
426   const Ty &Init;
427   initializer(const Ty &Val) : Init(Val) {}
428 
429   template <class Opt> void apply(Opt &O) const { O.setInitialValue(Init); }
430 };
431 
432 template <class Ty> initializer<Ty> init(const Ty &Val) {
433   return initializer<Ty>(Val);
434 }
435 
436 // location - Allow the user to specify which external variable they want to
437 // store the results of the command line argument processing into, if they don't
438 // want to store it in the option itself.
439 //
440 template <class Ty> struct LocationClass {
441   Ty &Loc;
442 
443   LocationClass(Ty &L) : Loc(L) {}
444 
445   template <class Opt> void apply(Opt &O) const { O.setLocation(O, Loc); }
446 };
447 
448 template <class Ty> LocationClass<Ty> location(Ty &L) {
449   return LocationClass<Ty>(L);
450 }
451 
452 // cat - Specifiy the Option category for the command line argument to belong
453 // to.
454 struct cat {
455   OptionCategory &Category;
456 
457   cat(OptionCategory &c) : Category(c) {}
458 
459   template <class Opt> void apply(Opt &O) const { O.addCategory(Category); }
460 };
461 
462 // sub - Specify the subcommand that this option belongs to.
463 struct sub {
464   SubCommand &Sub;
465 
466   sub(SubCommand &S) : Sub(S) {}
467 
468   template <class Opt> void apply(Opt &O) const { O.addSubCommand(Sub); }
469 };
470 
471 //===----------------------------------------------------------------------===//
472 // OptionValue class
473 
474 // Support value comparison outside the template.
475 struct GenericOptionValue {
476   virtual bool compare(const GenericOptionValue &V) const = 0;
477 
478 protected:
479   GenericOptionValue() = default;
480   GenericOptionValue(const GenericOptionValue&) = default;
481   GenericOptionValue &operator=(const GenericOptionValue &) = default;
482   ~GenericOptionValue() = default;
483 
484 private:
485   virtual void anchor();
486 };
487 
488 template <class DataType> struct OptionValue;
489 
490 // The default value safely does nothing. Option value printing is only
491 // best-effort.
492 template <class DataType, bool isClass>
493 struct OptionValueBase : public GenericOptionValue {
494   // Temporary storage for argument passing.
495   using WrapperType = OptionValue<DataType>;
496 
497   bool hasValue() const { return false; }
498 
499   const DataType &getValue() const { llvm_unreachable("no default value"); }
500 
501   // Some options may take their value from a different data type.
502   template <class DT> void setValue(const DT & /*V*/) {}
503 
504   bool compare(const DataType & /*V*/) const { return false; }
505 
506   bool compare(const GenericOptionValue & /*V*/) const override {
507     return false;
508   }
509 
510 protected:
511   ~OptionValueBase() = default;
512 };
513 
514 // Simple copy of the option value.
515 template <class DataType> class OptionValueCopy : public GenericOptionValue {
516   DataType Value;
517   bool Valid = false;
518 
519 protected:
520   OptionValueCopy(const OptionValueCopy&) = default;
521   OptionValueCopy &operator=(const OptionValueCopy &) = default;
522   ~OptionValueCopy() = default;
523 
524 public:
525   OptionValueCopy() = default;
526 
527   bool hasValue() const { return Valid; }
528 
529   const DataType &getValue() const {
530     assert(Valid && "invalid option value");
531     return Value;
532   }
533 
534   void setValue(const DataType &V) {
535     Valid = true;
536     Value = V;
537   }
538 
539   bool compare(const DataType &V) const { return Valid && (Value != V); }
540 
541   bool compare(const GenericOptionValue &V) const override {
542     const OptionValueCopy<DataType> &VC =
543         static_cast<const OptionValueCopy<DataType> &>(V);
544     if (!VC.hasValue())
545       return false;
546     return compare(VC.getValue());
547   }
548 };
549 
550 // Non-class option values.
551 template <class DataType>
552 struct OptionValueBase<DataType, false> : OptionValueCopy<DataType> {
553   using WrapperType = DataType;
554 
555 protected:
556   OptionValueBase() = default;
557   OptionValueBase(const OptionValueBase&) = default;
558   OptionValueBase &operator=(const OptionValueBase &) = default;
559   ~OptionValueBase() = default;
560 };
561 
562 // Top-level option class.
563 template <class DataType>
564 struct OptionValue final
565     : OptionValueBase<DataType, std::is_class<DataType>::value> {
566   OptionValue() = default;
567 
568   OptionValue(const DataType &V) { this->setValue(V); }
569 
570   // Some options may take their value from a different data type.
571   template <class DT> OptionValue<DataType> &operator=(const DT &V) {
572     this->setValue(V);
573     return *this;
574   }
575 };
576 
577 // Other safe-to-copy-by-value common option types.
578 enum boolOrDefault { BOU_UNSET, BOU_TRUE, BOU_FALSE };
579 template <>
580 struct OptionValue<cl::boolOrDefault> final
581     : OptionValueCopy<cl::boolOrDefault> {
582   using WrapperType = cl::boolOrDefault;
583 
584   OptionValue() = default;
585 
586   OptionValue(const cl::boolOrDefault &V) { this->setValue(V); }
587 
588   OptionValue<cl::boolOrDefault> &operator=(const cl::boolOrDefault &V) {
589     setValue(V);
590     return *this;
591   }
592 
593 private:
594   void anchor() override;
595 };
596 
597 template <>
598 struct OptionValue<std::string> final : OptionValueCopy<std::string> {
599   using WrapperType = StringRef;
600 
601   OptionValue() = default;
602 
603   OptionValue(const std::string &V) { this->setValue(V); }
604 
605   OptionValue<std::string> &operator=(const std::string &V) {
606     setValue(V);
607     return *this;
608   }
609 
610 private:
611   void anchor() override;
612 };
613 
614 //===----------------------------------------------------------------------===//
615 // Enum valued command line option
616 //
617 
618 // This represents a single enum value, using "int" as the underlying type.
619 struct OptionEnumValue {
620   StringRef Name;
621   int Value;
622   StringRef Description;
623 };
624 
625 #define clEnumVal(ENUMVAL, DESC)                                               \
626   llvm::cl::OptionEnumValue { #ENUMVAL, int(ENUMVAL), DESC }
627 #define clEnumValN(ENUMVAL, FLAGNAME, DESC)                                    \
628   llvm::cl::OptionEnumValue { FLAGNAME, int(ENUMVAL), DESC }
629 
630 // values - For custom data types, allow specifying a group of values together
631 // as the values that go into the mapping that the option handler uses.
632 //
633 class ValuesClass {
634   // Use a vector instead of a map, because the lists should be short,
635   // the overhead is less, and most importantly, it keeps them in the order
636   // inserted so we can print our option out nicely.
637   SmallVector<OptionEnumValue, 4> Values;
638 
639 public:
640   ValuesClass(std::initializer_list<OptionEnumValue> Options)
641       : Values(Options) {}
642 
643   template <class Opt> void apply(Opt &O) const {
644     for (auto Value : Values)
645       O.getParser().addLiteralOption(Value.Name, Value.Value,
646                                      Value.Description);
647   }
648 };
649 
650 /// Helper to build a ValuesClass by forwarding a variable number of arguments
651 /// as an initializer list to the ValuesClass constructor.
652 template <typename... OptsTy> ValuesClass values(OptsTy... Options) {
653   return ValuesClass({Options...});
654 }
655 
656 //===----------------------------------------------------------------------===//
657 // parser class - Parameterizable parser for different data types.  By default,
658 // known data types (string, int, bool) have specialized parsers, that do what
659 // you would expect.  The default parser, used for data types that are not
660 // built-in, uses a mapping table to map specific options to values, which is
661 // used, among other things, to handle enum types.
662 
663 //--------------------------------------------------
664 // generic_parser_base - This class holds all the non-generic code that we do
665 // not need replicated for every instance of the generic parser.  This also
666 // allows us to put stuff into CommandLine.cpp
667 //
668 class generic_parser_base {
669 protected:
670   class GenericOptionInfo {
671   public:
672     GenericOptionInfo(StringRef name, StringRef helpStr)
673         : Name(name), HelpStr(helpStr) {}
674     StringRef Name;
675     StringRef HelpStr;
676   };
677 
678 public:
679   generic_parser_base(Option &O) : Owner(O) {}
680 
681   virtual ~generic_parser_base() = default;
682   // Base class should have virtual-destructor
683 
684   // getNumOptions - Virtual function implemented by generic subclass to
685   // indicate how many entries are in Values.
686   //
687   virtual unsigned getNumOptions() const = 0;
688 
689   // getOption - Return option name N.
690   virtual StringRef getOption(unsigned N) const = 0;
691 
692   // getDescription - Return description N
693   virtual StringRef getDescription(unsigned N) const = 0;
694 
695   // Return the width of the option tag for printing...
696   virtual size_t getOptionWidth(const Option &O) const;
697 
698   virtual const GenericOptionValue &getOptionValue(unsigned N) const = 0;
699 
700   // printOptionInfo - Print out information about this option.  The
701   // to-be-maintained width is specified.
702   //
703   virtual void printOptionInfo(const Option &O, size_t GlobalWidth) const;
704 
705   void printGenericOptionDiff(const Option &O, const GenericOptionValue &V,
706                               const GenericOptionValue &Default,
707                               size_t GlobalWidth) const;
708 
709   // printOptionDiff - print the value of an option and it's default.
710   //
711   // Template definition ensures that the option and default have the same
712   // DataType (via the same AnyOptionValue).
713   template <class AnyOptionValue>
714   void printOptionDiff(const Option &O, const AnyOptionValue &V,
715                        const AnyOptionValue &Default,
716                        size_t GlobalWidth) const {
717     printGenericOptionDiff(O, V, Default, GlobalWidth);
718   }
719 
720   void initialize() {}
721 
722   void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) {
723     // If there has been no argstr specified, that means that we need to add an
724     // argument for every possible option.  This ensures that our options are
725     // vectored to us.
726     if (!Owner.hasArgStr())
727       for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
728         OptionNames.push_back(getOption(i));
729   }
730 
731   enum ValueExpected getValueExpectedFlagDefault() const {
732     // If there is an ArgStr specified, then we are of the form:
733     //
734     //    -opt=O2   or   -opt O2  or  -optO2
735     //
736     // In which case, the value is required.  Otherwise if an arg str has not
737     // been specified, we are of the form:
738     //
739     //    -O2 or O2 or -la (where -l and -a are separate options)
740     //
741     // If this is the case, we cannot allow a value.
742     //
743     if (Owner.hasArgStr())
744       return ValueRequired;
745     else
746       return ValueDisallowed;
747   }
748 
749   // findOption - Return the option number corresponding to the specified
750   // argument string.  If the option is not found, getNumOptions() is returned.
751   //
752   unsigned findOption(StringRef Name);
753 
754 protected:
755   Option &Owner;
756 };
757 
758 // Default parser implementation - This implementation depends on having a
759 // mapping of recognized options to values of some sort.  In addition to this,
760 // each entry in the mapping also tracks a help message that is printed with the
761 // command line option for -help.  Because this is a simple mapping parser, the
762 // data type can be any unsupported type.
763 //
764 template <class DataType> class parser : public generic_parser_base {
765 protected:
766   class OptionInfo : public GenericOptionInfo {
767   public:
768     OptionInfo(StringRef name, DataType v, StringRef helpStr)
769         : GenericOptionInfo(name, helpStr), V(v) {}
770 
771     OptionValue<DataType> V;
772   };
773   SmallVector<OptionInfo, 8> Values;
774 
775 public:
776   parser(Option &O) : generic_parser_base(O) {}
777 
778   using parser_data_type = DataType;
779 
780   // Implement virtual functions needed by generic_parser_base
781   unsigned getNumOptions() const override { return unsigned(Values.size()); }
782   StringRef getOption(unsigned N) const override { return Values[N].Name; }
783   StringRef getDescription(unsigned N) const override {
784     return Values[N].HelpStr;
785   }
786 
787   // getOptionValue - Return the value of option name N.
788   const GenericOptionValue &getOptionValue(unsigned N) const override {
789     return Values[N].V;
790   }
791 
792   // parse - Return true on error.
793   bool parse(Option &O, StringRef ArgName, StringRef Arg, DataType &V) {
794     StringRef ArgVal;
795     if (Owner.hasArgStr())
796       ArgVal = Arg;
797     else
798       ArgVal = ArgName;
799 
800     for (size_t i = 0, e = Values.size(); i != e; ++i)
801       if (Values[i].Name == ArgVal) {
802         V = Values[i].V.getValue();
803         return false;
804       }
805 
806     return O.error("Cannot find option named '" + ArgVal + "'!");
807   }
808 
809   /// addLiteralOption - Add an entry to the mapping table.
810   ///
811   template <class DT>
812   void addLiteralOption(StringRef Name, const DT &V, StringRef HelpStr) {
813     assert(findOption(Name) == Values.size() && "Option already exists!");
814     OptionInfo X(Name, static_cast<DataType>(V), HelpStr);
815     Values.push_back(X);
816     AddLiteralOption(Owner, Name);
817   }
818 
819   /// removeLiteralOption - Remove the specified option.
820   ///
821   void removeLiteralOption(StringRef Name) {
822     unsigned N = findOption(Name);
823     assert(N != Values.size() && "Option not found!");
824     Values.erase(Values.begin() + N);
825   }
826 };
827 
828 //--------------------------------------------------
829 // basic_parser - Super class of parsers to provide boilerplate code
830 //
831 class basic_parser_impl { // non-template implementation of basic_parser<t>
832 public:
833   basic_parser_impl(Option &) {}
834 
835   virtual ~basic_parser_impl() {}
836 
837   enum ValueExpected getValueExpectedFlagDefault() const {
838     return ValueRequired;
839   }
840 
841   void getExtraOptionNames(SmallVectorImpl<StringRef> &) {}
842 
843   void initialize() {}
844 
845   // Return the width of the option tag for printing...
846   size_t getOptionWidth(const Option &O) const;
847 
848   // printOptionInfo - Print out information about this option.  The
849   // to-be-maintained width is specified.
850   //
851   void printOptionInfo(const Option &O, size_t GlobalWidth) const;
852 
853   // printOptionNoValue - Print a placeholder for options that don't yet support
854   // printOptionDiff().
855   void printOptionNoValue(const Option &O, size_t GlobalWidth) const;
856 
857   // getValueName - Overload in subclass to provide a better default value.
858   virtual StringRef getValueName() const { return "value"; }
859 
860   // An out-of-line virtual method to provide a 'home' for this class.
861   virtual void anchor();
862 
863 protected:
864   // A helper for basic_parser::printOptionDiff.
865   void printOptionName(const Option &O, size_t GlobalWidth) const;
866 };
867 
868 // basic_parser - The real basic parser is just a template wrapper that provides
869 // a typedef for the provided data type.
870 //
871 template <class DataType> class basic_parser : public basic_parser_impl {
872 public:
873   using parser_data_type = DataType;
874   using OptVal = OptionValue<DataType>;
875 
876   basic_parser(Option &O) : basic_parser_impl(O) {}
877 };
878 
879 //--------------------------------------------------
880 // parser<bool>
881 //
882 template <> class parser<bool> : public basic_parser<bool> {
883 public:
884   parser(Option &O) : basic_parser(O) {}
885 
886   // parse - Return true on error.
887   bool parse(Option &O, StringRef ArgName, StringRef Arg, bool &Val);
888 
889   void initialize() {}
890 
891   enum ValueExpected getValueExpectedFlagDefault() const {
892     return ValueOptional;
893   }
894 
895   // getValueName - Do not print =<value> at all.
896   StringRef getValueName() const override { return StringRef(); }
897 
898   void printOptionDiff(const Option &O, bool V, OptVal Default,
899                        size_t GlobalWidth) const;
900 
901   // An out-of-line virtual method to provide a 'home' for this class.
902   void anchor() override;
903 };
904 
905 extern template class basic_parser<bool>;
906 
907 //--------------------------------------------------
908 // parser<boolOrDefault>
909 template <> class parser<boolOrDefault> : public basic_parser<boolOrDefault> {
910 public:
911   parser(Option &O) : basic_parser(O) {}
912 
913   // parse - Return true on error.
914   bool parse(Option &O, StringRef ArgName, StringRef Arg, boolOrDefault &Val);
915 
916   enum ValueExpected getValueExpectedFlagDefault() const {
917     return ValueOptional;
918   }
919 
920   // getValueName - Do not print =<value> at all.
921   StringRef getValueName() const override { return StringRef(); }
922 
923   void printOptionDiff(const Option &O, boolOrDefault V, OptVal Default,
924                        size_t GlobalWidth) const;
925 
926   // An out-of-line virtual method to provide a 'home' for this class.
927   void anchor() override;
928 };
929 
930 extern template class basic_parser<boolOrDefault>;
931 
932 //--------------------------------------------------
933 // parser<int>
934 //
935 template <> class parser<int> : public basic_parser<int> {
936 public:
937   parser(Option &O) : basic_parser(O) {}
938 
939   // parse - Return true on error.
940   bool parse(Option &O, StringRef ArgName, StringRef Arg, int &Val);
941 
942   // getValueName - Overload in subclass to provide a better default value.
943   StringRef getValueName() const override { return "int"; }
944 
945   void printOptionDiff(const Option &O, int V, OptVal Default,
946                        size_t GlobalWidth) const;
947 
948   // An out-of-line virtual method to provide a 'home' for this class.
949   void anchor() override;
950 };
951 
952 extern template class basic_parser<int>;
953 
954 //--------------------------------------------------
955 // parser<unsigned>
956 //
957 template <> class parser<unsigned> : public basic_parser<unsigned> {
958 public:
959   parser(Option &O) : basic_parser(O) {}
960 
961   // parse - Return true on error.
962   bool parse(Option &O, StringRef ArgName, StringRef Arg, unsigned &Val);
963 
964   // getValueName - Overload in subclass to provide a better default value.
965   StringRef getValueName() const override { return "uint"; }
966 
967   void printOptionDiff(const Option &O, unsigned V, OptVal Default,
968                        size_t GlobalWidth) const;
969 
970   // An out-of-line virtual method to provide a 'home' for this class.
971   void anchor() override;
972 };
973 
974 extern template class basic_parser<unsigned>;
975 
976 //--------------------------------------------------
977 // parser<unsigned long>
978 //
979 template <>
980 class parser<unsigned long> final : public basic_parser<unsigned long> {
981 public:
982   parser(Option &O) : basic_parser(O) {}
983 
984   // parse - Return true on error.
985   bool parse(Option &O, StringRef ArgName, StringRef Arg, unsigned long &Val);
986 
987   // getValueName - Overload in subclass to provide a better default value.
988   StringRef getValueName() const override { return "ulong"; }
989 
990   void printOptionDiff(const Option &O, unsigned long V, OptVal Default,
991                        size_t GlobalWidth) const;
992 
993   // An out-of-line virtual method to provide a 'home' for this class.
994   void anchor() override;
995 };
996 
997 extern template class basic_parser<unsigned long>;
998 
999 //--------------------------------------------------
1000 // parser<unsigned long long>
1001 //
1002 template <>
1003 class parser<unsigned long long> : public basic_parser<unsigned long long> {
1004 public:
1005   parser(Option &O) : basic_parser(O) {}
1006 
1007   // parse - Return true on error.
1008   bool parse(Option &O, StringRef ArgName, StringRef Arg,
1009              unsigned long long &Val);
1010 
1011   // getValueName - Overload in subclass to provide a better default value.
1012   StringRef getValueName() const override { return "ulong"; }
1013 
1014   void printOptionDiff(const Option &O, unsigned long long V, OptVal Default,
1015                        size_t GlobalWidth) const;
1016 
1017   // An out-of-line virtual method to provide a 'home' for this class.
1018   void anchor() override;
1019 };
1020 
1021 extern template class basic_parser<unsigned long long>;
1022 
1023 //--------------------------------------------------
1024 // parser<double>
1025 //
1026 template <> class parser<double> : public basic_parser<double> {
1027 public:
1028   parser(Option &O) : basic_parser(O) {}
1029 
1030   // parse - Return true on error.
1031   bool parse(Option &O, StringRef ArgName, StringRef Arg, double &Val);
1032 
1033   // getValueName - Overload in subclass to provide a better default value.
1034   StringRef getValueName() const override { return "number"; }
1035 
1036   void printOptionDiff(const Option &O, double V, OptVal Default,
1037                        size_t GlobalWidth) const;
1038 
1039   // An out-of-line virtual method to provide a 'home' for this class.
1040   void anchor() override;
1041 };
1042 
1043 extern template class basic_parser<double>;
1044 
1045 //--------------------------------------------------
1046 // parser<float>
1047 //
1048 template <> class parser<float> : public basic_parser<float> {
1049 public:
1050   parser(Option &O) : basic_parser(O) {}
1051 
1052   // parse - Return true on error.
1053   bool parse(Option &O, StringRef ArgName, StringRef Arg, float &Val);
1054 
1055   // getValueName - Overload in subclass to provide a better default value.
1056   StringRef getValueName() const override { return "number"; }
1057 
1058   void printOptionDiff(const Option &O, float V, OptVal Default,
1059                        size_t GlobalWidth) const;
1060 
1061   // An out-of-line virtual method to provide a 'home' for this class.
1062   void anchor() override;
1063 };
1064 
1065 extern template class basic_parser<float>;
1066 
1067 //--------------------------------------------------
1068 // parser<std::string>
1069 //
1070 template <> class parser<std::string> : public basic_parser<std::string> {
1071 public:
1072   parser(Option &O) : basic_parser(O) {}
1073 
1074   // parse - Return true on error.
1075   bool parse(Option &, StringRef, StringRef Arg, std::string &Value) {
1076     Value = Arg.str();
1077     return false;
1078   }
1079 
1080   // getValueName - Overload in subclass to provide a better default value.
1081   StringRef getValueName() const override { return "string"; }
1082 
1083   void printOptionDiff(const Option &O, StringRef V, const OptVal &Default,
1084                        size_t GlobalWidth) const;
1085 
1086   // An out-of-line virtual method to provide a 'home' for this class.
1087   void anchor() override;
1088 };
1089 
1090 extern template class basic_parser<std::string>;
1091 
1092 //--------------------------------------------------
1093 // parser<char>
1094 //
1095 template <> class parser<char> : public basic_parser<char> {
1096 public:
1097   parser(Option &O) : basic_parser(O) {}
1098 
1099   // parse - Return true on error.
1100   bool parse(Option &, StringRef, StringRef Arg, char &Value) {
1101     Value = Arg[0];
1102     return false;
1103   }
1104 
1105   // getValueName - Overload in subclass to provide a better default value.
1106   StringRef getValueName() const override { return "char"; }
1107 
1108   void printOptionDiff(const Option &O, char V, OptVal Default,
1109                        size_t GlobalWidth) const;
1110 
1111   // An out-of-line virtual method to provide a 'home' for this class.
1112   void anchor() override;
1113 };
1114 
1115 extern template class basic_parser<char>;
1116 
1117 //--------------------------------------------------
1118 // PrintOptionDiff
1119 //
1120 // This collection of wrappers is the intermediary between class opt and class
1121 // parser to handle all the template nastiness.
1122 
1123 // This overloaded function is selected by the generic parser.
1124 template <class ParserClass, class DT>
1125 void printOptionDiff(const Option &O, const generic_parser_base &P, const DT &V,
1126                      const OptionValue<DT> &Default, size_t GlobalWidth) {
1127   OptionValue<DT> OV = V;
1128   P.printOptionDiff(O, OV, Default, GlobalWidth);
1129 }
1130 
1131 // This is instantiated for basic parsers when the parsed value has a different
1132 // type than the option value. e.g. HelpPrinter.
1133 template <class ParserDT, class ValDT> struct OptionDiffPrinter {
1134   void print(const Option &O, const parser<ParserDT> &P, const ValDT & /*V*/,
1135              const OptionValue<ValDT> & /*Default*/, size_t GlobalWidth) {
1136     P.printOptionNoValue(O, GlobalWidth);
1137   }
1138 };
1139 
1140 // This is instantiated for basic parsers when the parsed value has the same
1141 // type as the option value.
1142 template <class DT> struct OptionDiffPrinter<DT, DT> {
1143   void print(const Option &O, const parser<DT> &P, const DT &V,
1144              const OptionValue<DT> &Default, size_t GlobalWidth) {
1145     P.printOptionDiff(O, V, Default, GlobalWidth);
1146   }
1147 };
1148 
1149 // This overloaded function is selected by the basic parser, which may parse a
1150 // different type than the option type.
1151 template <class ParserClass, class ValDT>
1152 void printOptionDiff(
1153     const Option &O,
1154     const basic_parser<typename ParserClass::parser_data_type> &P,
1155     const ValDT &V, const OptionValue<ValDT> &Default, size_t GlobalWidth) {
1156 
1157   OptionDiffPrinter<typename ParserClass::parser_data_type, ValDT> printer;
1158   printer.print(O, static_cast<const ParserClass &>(P), V, Default,
1159                 GlobalWidth);
1160 }
1161 
1162 //===----------------------------------------------------------------------===//
1163 // applicator class - This class is used because we must use partial
1164 // specialization to handle literal string arguments specially (const char* does
1165 // not correctly respond to the apply method).  Because the syntax to use this
1166 // is a pain, we have the 'apply' method below to handle the nastiness...
1167 //
1168 template <class Mod> struct applicator {
1169   template <class Opt> static void opt(const Mod &M, Opt &O) { M.apply(O); }
1170 };
1171 
1172 // Handle const char* as a special case...
1173 template <unsigned n> struct applicator<char[n]> {
1174   template <class Opt> static void opt(StringRef Str, Opt &O) {
1175     O.setArgStr(Str);
1176   }
1177 };
1178 template <unsigned n> struct applicator<const char[n]> {
1179   template <class Opt> static void opt(StringRef Str, Opt &O) {
1180     O.setArgStr(Str);
1181   }
1182 };
1183 template <> struct applicator<StringRef > {
1184   template <class Opt> static void opt(StringRef Str, Opt &O) {
1185     O.setArgStr(Str);
1186   }
1187 };
1188 
1189 template <> struct applicator<NumOccurrencesFlag> {
1190   static void opt(NumOccurrencesFlag N, Option &O) {
1191     O.setNumOccurrencesFlag(N);
1192   }
1193 };
1194 
1195 template <> struct applicator<ValueExpected> {
1196   static void opt(ValueExpected VE, Option &O) { O.setValueExpectedFlag(VE); }
1197 };
1198 
1199 template <> struct applicator<OptionHidden> {
1200   static void opt(OptionHidden OH, Option &O) { O.setHiddenFlag(OH); }
1201 };
1202 
1203 template <> struct applicator<FormattingFlags> {
1204   static void opt(FormattingFlags FF, Option &O) { O.setFormattingFlag(FF); }
1205 };
1206 
1207 template <> struct applicator<MiscFlags> {
1208   static void opt(MiscFlags MF, Option &O) {
1209     assert((MF != Grouping || O.ArgStr.size() == 1) &&
1210            "cl::Grouping can only apply to single charater Options.");
1211     O.setMiscFlag(MF);
1212   }
1213 };
1214 
1215 // apply method - Apply modifiers to an option in a type safe way.
1216 template <class Opt, class Mod, class... Mods>
1217 void apply(Opt *O, const Mod &M, const Mods &... Ms) {
1218   applicator<Mod>::opt(M, *O);
1219   apply(O, Ms...);
1220 }
1221 
1222 template <class Opt, class Mod> void apply(Opt *O, const Mod &M) {
1223   applicator<Mod>::opt(M, *O);
1224 }
1225 
1226 //===----------------------------------------------------------------------===//
1227 // opt_storage class
1228 
1229 // Default storage class definition: external storage.  This implementation
1230 // assumes the user will specify a variable to store the data into with the
1231 // cl::location(x) modifier.
1232 //
1233 template <class DataType, bool ExternalStorage, bool isClass>
1234 class opt_storage {
1235   DataType *Location = nullptr; // Where to store the object...
1236   OptionValue<DataType> Default;
1237 
1238   void check_location() const {
1239     assert(Location && "cl::location(...) not specified for a command "
1240                        "line option with external storage, "
1241                        "or cl::init specified before cl::location()!!");
1242   }
1243 
1244 public:
1245   opt_storage() = default;
1246 
1247   bool setLocation(Option &O, DataType &L) {
1248     if (Location)
1249       return O.error("cl::location(x) specified more than once!");
1250     Location = &L;
1251     Default = L;
1252     return false;
1253   }
1254 
1255   template <class T> void setValue(const T &V, bool initial = false) {
1256     check_location();
1257     *Location = V;
1258     if (initial)
1259       Default = V;
1260   }
1261 
1262   DataType &getValue() {
1263     check_location();
1264     return *Location;
1265   }
1266   const DataType &getValue() const {
1267     check_location();
1268     return *Location;
1269   }
1270 
1271   operator DataType() const { return this->getValue(); }
1272 
1273   const OptionValue<DataType> &getDefault() const { return Default; }
1274 };
1275 
1276 // Define how to hold a class type object, such as a string.  Since we can
1277 // inherit from a class, we do so.  This makes us exactly compatible with the
1278 // object in all cases that it is used.
1279 //
1280 template <class DataType>
1281 class opt_storage<DataType, false, true> : public DataType {
1282 public:
1283   OptionValue<DataType> Default;
1284 
1285   template <class T> void setValue(const T &V, bool initial = false) {
1286     DataType::operator=(V);
1287     if (initial)
1288       Default = V;
1289   }
1290 
1291   DataType &getValue() { return *this; }
1292   const DataType &getValue() const { return *this; }
1293 
1294   const OptionValue<DataType> &getDefault() const { return Default; }
1295 };
1296 
1297 // Define a partial specialization to handle things we cannot inherit from.  In
1298 // this case, we store an instance through containment, and overload operators
1299 // to get at the value.
1300 //
1301 template <class DataType> class opt_storage<DataType, false, false> {
1302 public:
1303   DataType Value;
1304   OptionValue<DataType> Default;
1305 
1306   // Make sure we initialize the value with the default constructor for the
1307   // type.
1308   opt_storage() : Value(DataType()), Default(DataType()) {}
1309 
1310   template <class T> void setValue(const T &V, bool initial = false) {
1311     Value = V;
1312     if (initial)
1313       Default = V;
1314   }
1315   DataType &getValue() { return Value; }
1316   DataType getValue() const { return Value; }
1317 
1318   const OptionValue<DataType> &getDefault() const { return Default; }
1319 
1320   operator DataType() const { return getValue(); }
1321 
1322   // If the datatype is a pointer, support -> on it.
1323   DataType operator->() const { return Value; }
1324 };
1325 
1326 //===----------------------------------------------------------------------===//
1327 // opt - A scalar command line option.
1328 //
1329 template <class DataType, bool ExternalStorage = false,
1330           class ParserClass = parser<DataType>>
1331 class opt : public Option,
1332             public opt_storage<DataType, ExternalStorage,
1333                                std::is_class<DataType>::value> {
1334   ParserClass Parser;
1335 
1336   bool handleOccurrence(unsigned pos, StringRef ArgName,
1337                         StringRef Arg) override {
1338     typename ParserClass::parser_data_type Val =
1339         typename ParserClass::parser_data_type();
1340     if (Parser.parse(*this, ArgName, Arg, Val))
1341       return true; // Parse error!
1342     this->setValue(Val);
1343     this->setPosition(pos);
1344     return false;
1345   }
1346 
1347   enum ValueExpected getValueExpectedFlagDefault() const override {
1348     return Parser.getValueExpectedFlagDefault();
1349   }
1350 
1351   void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1352     return Parser.getExtraOptionNames(OptionNames);
1353   }
1354 
1355   // Forward printing stuff to the parser...
1356   size_t getOptionWidth() const override {
1357     return Parser.getOptionWidth(*this);
1358   }
1359 
1360   void printOptionInfo(size_t GlobalWidth) const override {
1361     Parser.printOptionInfo(*this, GlobalWidth);
1362   }
1363 
1364   void printOptionValue(size_t GlobalWidth, bool Force) const override {
1365     if (Force || this->getDefault().compare(this->getValue())) {
1366       cl::printOptionDiff<ParserClass>(*this, Parser, this->getValue(),
1367                                        this->getDefault(), GlobalWidth);
1368     }
1369   }
1370 
1371   template <class T, class = typename std::enable_if<
1372             std::is_assignable<T&, T>::value>::type>
1373   void setDefaultImpl() {
1374     const OptionValue<DataType> &V = this->getDefault();
1375     if (V.hasValue())
1376       this->setValue(V.getValue());
1377   }
1378 
1379   template <class T, class = typename std::enable_if<
1380             !std::is_assignable<T&, T>::value>::type>
1381   void setDefaultImpl(...) {}
1382 
1383   void setDefault() override { setDefaultImpl<DataType>(); }
1384 
1385   void done() {
1386     addArgument();
1387     Parser.initialize();
1388   }
1389 
1390 public:
1391   // Command line options should not be copyable
1392   opt(const opt &) = delete;
1393   opt &operator=(const opt &) = delete;
1394 
1395   // setInitialValue - Used by the cl::init modifier...
1396   void setInitialValue(const DataType &V) { this->setValue(V, true); }
1397 
1398   ParserClass &getParser() { return Parser; }
1399 
1400   template <class T> DataType &operator=(const T &Val) {
1401     this->setValue(Val);
1402     return this->getValue();
1403   }
1404 
1405   template <class... Mods>
1406   explicit opt(const Mods &... Ms)
1407       : Option(Optional, NotHidden), Parser(*this) {
1408     apply(this, Ms...);
1409     done();
1410   }
1411 };
1412 
1413 extern template class opt<unsigned>;
1414 extern template class opt<int>;
1415 extern template class opt<std::string>;
1416 extern template class opt<char>;
1417 extern template class opt<bool>;
1418 
1419 //===----------------------------------------------------------------------===//
1420 // list_storage class
1421 
1422 // Default storage class definition: external storage.  This implementation
1423 // assumes the user will specify a variable to store the data into with the
1424 // cl::location(x) modifier.
1425 //
1426 template <class DataType, class StorageClass> class list_storage {
1427   StorageClass *Location = nullptr; // Where to store the object...
1428 
1429 public:
1430   list_storage() = default;
1431 
1432   void clear() {}
1433 
1434   bool setLocation(Option &O, StorageClass &L) {
1435     if (Location)
1436       return O.error("cl::location(x) specified more than once!");
1437     Location = &L;
1438     return false;
1439   }
1440 
1441   template <class T> void addValue(const T &V) {
1442     assert(Location != 0 && "cl::location(...) not specified for a command "
1443                             "line option with external storage!");
1444     Location->push_back(V);
1445   }
1446 };
1447 
1448 // Define how to hold a class type object, such as a string.
1449 // Originally this code inherited from std::vector. In transitioning to a new
1450 // API for command line options we should change this. The new implementation
1451 // of this list_storage specialization implements the minimum subset of the
1452 // std::vector API required for all the current clients.
1453 //
1454 // FIXME: Reduce this API to a more narrow subset of std::vector
1455 //
1456 template <class DataType> class list_storage<DataType, bool> {
1457   std::vector<DataType> Storage;
1458 
1459 public:
1460   using iterator = typename std::vector<DataType>::iterator;
1461 
1462   iterator begin() { return Storage.begin(); }
1463   iterator end() { return Storage.end(); }
1464 
1465   using const_iterator = typename std::vector<DataType>::const_iterator;
1466 
1467   const_iterator begin() const { return Storage.begin(); }
1468   const_iterator end() const { return Storage.end(); }
1469 
1470   using size_type = typename std::vector<DataType>::size_type;
1471 
1472   size_type size() const { return Storage.size(); }
1473 
1474   bool empty() const { return Storage.empty(); }
1475 
1476   void push_back(const DataType &value) { Storage.push_back(value); }
1477   void push_back(DataType &&value) { Storage.push_back(value); }
1478 
1479   using reference = typename std::vector<DataType>::reference;
1480   using const_reference = typename std::vector<DataType>::const_reference;
1481 
1482   reference operator[](size_type pos) { return Storage[pos]; }
1483   const_reference operator[](size_type pos) const { return Storage[pos]; }
1484 
1485   void clear() {
1486     Storage.clear();
1487   }
1488 
1489   iterator erase(const_iterator pos) { return Storage.erase(pos); }
1490   iterator erase(const_iterator first, const_iterator last) {
1491     return Storage.erase(first, last);
1492   }
1493 
1494   iterator erase(iterator pos) { return Storage.erase(pos); }
1495   iterator erase(iterator first, iterator last) {
1496     return Storage.erase(first, last);
1497   }
1498 
1499   iterator insert(const_iterator pos, const DataType &value) {
1500     return Storage.insert(pos, value);
1501   }
1502   iterator insert(const_iterator pos, DataType &&value) {
1503     return Storage.insert(pos, value);
1504   }
1505 
1506   iterator insert(iterator pos, const DataType &value) {
1507     return Storage.insert(pos, value);
1508   }
1509   iterator insert(iterator pos, DataType &&value) {
1510     return Storage.insert(pos, value);
1511   }
1512 
1513   reference front() { return Storage.front(); }
1514   const_reference front() const { return Storage.front(); }
1515 
1516   operator std::vector<DataType>&() { return Storage; }
1517   operator ArrayRef<DataType>() { return Storage; }
1518   std::vector<DataType> *operator&() { return &Storage; }
1519   const std::vector<DataType> *operator&() const { return &Storage; }
1520 
1521   template <class T> void addValue(const T &V) { Storage.push_back(V); }
1522 };
1523 
1524 //===----------------------------------------------------------------------===//
1525 // list - A list of command line options.
1526 //
1527 template <class DataType, class StorageClass = bool,
1528           class ParserClass = parser<DataType>>
1529 class list : public Option, public list_storage<DataType, StorageClass> {
1530   std::vector<unsigned> Positions;
1531   ParserClass Parser;
1532 
1533   enum ValueExpected getValueExpectedFlagDefault() const override {
1534     return Parser.getValueExpectedFlagDefault();
1535   }
1536 
1537   void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1538     return Parser.getExtraOptionNames(OptionNames);
1539   }
1540 
1541   bool handleOccurrence(unsigned pos, StringRef ArgName,
1542                         StringRef Arg) override {
1543     typename ParserClass::parser_data_type Val =
1544         typename ParserClass::parser_data_type();
1545     if (Parser.parse(*this, ArgName, Arg, Val))
1546       return true; // Parse Error!
1547     list_storage<DataType, StorageClass>::addValue(Val);
1548     setPosition(pos);
1549     Positions.push_back(pos);
1550     return false;
1551   }
1552 
1553   // Forward printing stuff to the parser...
1554   size_t getOptionWidth() const override {
1555     return Parser.getOptionWidth(*this);
1556   }
1557 
1558   void printOptionInfo(size_t GlobalWidth) const override {
1559     Parser.printOptionInfo(*this, GlobalWidth);
1560   }
1561 
1562   // Unimplemented: list options don't currently store their default value.
1563   void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1564   }
1565 
1566   void setDefault() override {
1567     Positions.clear();
1568     list_storage<DataType, StorageClass>::clear();
1569   }
1570 
1571   void done() {
1572     addArgument();
1573     Parser.initialize();
1574   }
1575 
1576 public:
1577   // Command line options should not be copyable
1578   list(const list &) = delete;
1579   list &operator=(const list &) = delete;
1580 
1581   ParserClass &getParser() { return Parser; }
1582 
1583   unsigned getPosition(unsigned optnum) const {
1584     assert(optnum < this->size() && "Invalid option index");
1585     return Positions[optnum];
1586   }
1587 
1588   void setNumAdditionalVals(unsigned n) { Option::setNumAdditionalVals(n); }
1589 
1590   template <class... Mods>
1591   explicit list(const Mods &... Ms)
1592       : Option(ZeroOrMore, NotHidden), Parser(*this) {
1593     apply(this, Ms...);
1594     done();
1595   }
1596 };
1597 
1598 // multi_val - Modifier to set the number of additional values.
1599 struct multi_val {
1600   unsigned AdditionalVals;
1601   explicit multi_val(unsigned N) : AdditionalVals(N) {}
1602 
1603   template <typename D, typename S, typename P>
1604   void apply(list<D, S, P> &L) const {
1605     L.setNumAdditionalVals(AdditionalVals);
1606   }
1607 };
1608 
1609 //===----------------------------------------------------------------------===//
1610 // bits_storage class
1611 
1612 // Default storage class definition: external storage.  This implementation
1613 // assumes the user will specify a variable to store the data into with the
1614 // cl::location(x) modifier.
1615 //
1616 template <class DataType, class StorageClass> class bits_storage {
1617   unsigned *Location = nullptr; // Where to store the bits...
1618 
1619   template <class T> static unsigned Bit(const T &V) {
1620     unsigned BitPos = reinterpret_cast<unsigned>(V);
1621     assert(BitPos < sizeof(unsigned) * CHAR_BIT &&
1622            "enum exceeds width of bit vector!");
1623     return 1 << BitPos;
1624   }
1625 
1626 public:
1627   bits_storage() = default;
1628 
1629   bool setLocation(Option &O, unsigned &L) {
1630     if (Location)
1631       return O.error("cl::location(x) specified more than once!");
1632     Location = &L;
1633     return false;
1634   }
1635 
1636   template <class T> void addValue(const T &V) {
1637     assert(Location != 0 && "cl::location(...) not specified for a command "
1638                             "line option with external storage!");
1639     *Location |= Bit(V);
1640   }
1641 
1642   unsigned getBits() { return *Location; }
1643 
1644   template <class T> bool isSet(const T &V) {
1645     return (*Location & Bit(V)) != 0;
1646   }
1647 };
1648 
1649 // Define how to hold bits.  Since we can inherit from a class, we do so.
1650 // This makes us exactly compatible with the bits in all cases that it is used.
1651 //
1652 template <class DataType> class bits_storage<DataType, bool> {
1653   unsigned Bits; // Where to store the bits...
1654 
1655   template <class T> static unsigned Bit(const T &V) {
1656     unsigned BitPos = (unsigned)V;
1657     assert(BitPos < sizeof(unsigned) * CHAR_BIT &&
1658            "enum exceeds width of bit vector!");
1659     return 1 << BitPos;
1660   }
1661 
1662 public:
1663   template <class T> void addValue(const T &V) { Bits |= Bit(V); }
1664 
1665   unsigned getBits() { return Bits; }
1666 
1667   template <class T> bool isSet(const T &V) { return (Bits & Bit(V)) != 0; }
1668 };
1669 
1670 //===----------------------------------------------------------------------===//
1671 // bits - A bit vector of command options.
1672 //
1673 template <class DataType, class Storage = bool,
1674           class ParserClass = parser<DataType>>
1675 class bits : public Option, public bits_storage<DataType, Storage> {
1676   std::vector<unsigned> Positions;
1677   ParserClass Parser;
1678 
1679   enum ValueExpected getValueExpectedFlagDefault() const override {
1680     return Parser.getValueExpectedFlagDefault();
1681   }
1682 
1683   void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1684     return Parser.getExtraOptionNames(OptionNames);
1685   }
1686 
1687   bool handleOccurrence(unsigned pos, StringRef ArgName,
1688                         StringRef Arg) override {
1689     typename ParserClass::parser_data_type Val =
1690         typename ParserClass::parser_data_type();
1691     if (Parser.parse(*this, ArgName, Arg, Val))
1692       return true; // Parse Error!
1693     this->addValue(Val);
1694     setPosition(pos);
1695     Positions.push_back(pos);
1696     return false;
1697   }
1698 
1699   // Forward printing stuff to the parser...
1700   size_t getOptionWidth() const override {
1701     return Parser.getOptionWidth(*this);
1702   }
1703 
1704   void printOptionInfo(size_t GlobalWidth) const override {
1705     Parser.printOptionInfo(*this, GlobalWidth);
1706   }
1707 
1708   // Unimplemented: bits options don't currently store their default values.
1709   void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1710   }
1711 
1712   void setDefault() override {}
1713 
1714   void done() {
1715     addArgument();
1716     Parser.initialize();
1717   }
1718 
1719 public:
1720   // Command line options should not be copyable
1721   bits(const bits &) = delete;
1722   bits &operator=(const bits &) = delete;
1723 
1724   ParserClass &getParser() { return Parser; }
1725 
1726   unsigned getPosition(unsigned optnum) const {
1727     assert(optnum < this->size() && "Invalid option index");
1728     return Positions[optnum];
1729   }
1730 
1731   template <class... Mods>
1732   explicit bits(const Mods &... Ms)
1733       : Option(ZeroOrMore, NotHidden), Parser(*this) {
1734     apply(this, Ms...);
1735     done();
1736   }
1737 };
1738 
1739 //===----------------------------------------------------------------------===//
1740 // Aliased command line option (alias this name to a preexisting name)
1741 //
1742 
1743 class alias : public Option {
1744   Option *AliasFor;
1745 
1746   bool handleOccurrence(unsigned pos, StringRef /*ArgName*/,
1747                         StringRef Arg) override {
1748     return AliasFor->handleOccurrence(pos, AliasFor->ArgStr, Arg);
1749   }
1750 
1751   bool addOccurrence(unsigned pos, StringRef /*ArgName*/, StringRef Value,
1752                      bool MultiArg = false) override {
1753     return AliasFor->addOccurrence(pos, AliasFor->ArgStr, Value, MultiArg);
1754   }
1755 
1756   // Handle printing stuff...
1757   size_t getOptionWidth() const override;
1758   void printOptionInfo(size_t GlobalWidth) const override;
1759 
1760   // Aliases do not need to print their values.
1761   void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1762   }
1763 
1764   void setDefault() override { AliasFor->setDefault(); }
1765 
1766   ValueExpected getValueExpectedFlagDefault() const override {
1767     return AliasFor->getValueExpectedFlag();
1768   }
1769 
1770   void done() {
1771     if (!hasArgStr())
1772       error("cl::alias must have argument name specified!");
1773     if (!AliasFor)
1774       error("cl::alias must have an cl::aliasopt(option) specified!");
1775     if (!Subs.empty())
1776       error("cl::alias must not have cl::sub(), aliased option's cl::sub() will be used!");
1777     Subs = AliasFor->Subs;
1778     Categories = AliasFor->Categories;
1779     addArgument();
1780   }
1781 
1782 public:
1783   // Command line options should not be copyable
1784   alias(const alias &) = delete;
1785   alias &operator=(const alias &) = delete;
1786 
1787   void setAliasFor(Option &O) {
1788     if (AliasFor)
1789       error("cl::alias must only have one cl::aliasopt(...) specified!");
1790     AliasFor = &O;
1791   }
1792 
1793   template <class... Mods>
1794   explicit alias(const Mods &... Ms)
1795       : Option(Optional, Hidden), AliasFor(nullptr) {
1796     apply(this, Ms...);
1797     done();
1798   }
1799 };
1800 
1801 // aliasfor - Modifier to set the option an alias aliases.
1802 struct aliasopt {
1803   Option &Opt;
1804 
1805   explicit aliasopt(Option &O) : Opt(O) {}
1806 
1807   void apply(alias &A) const { A.setAliasFor(Opt); }
1808 };
1809 
1810 // extrahelp - provide additional help at the end of the normal help
1811 // output. All occurrences of cl::extrahelp will be accumulated and
1812 // printed to stderr at the end of the regular help, just before
1813 // exit is called.
1814 struct extrahelp {
1815   StringRef morehelp;
1816 
1817   explicit extrahelp(StringRef help);
1818 };
1819 
1820 void PrintVersionMessage();
1821 
1822 /// This function just prints the help message, exactly the same way as if the
1823 /// -help or -help-hidden option had been given on the command line.
1824 ///
1825 /// \param Hidden if true will print hidden options
1826 /// \param Categorized if true print options in categories
1827 void PrintHelpMessage(bool Hidden = false, bool Categorized = false);
1828 
1829 //===----------------------------------------------------------------------===//
1830 // Public interface for accessing registered options.
1831 //
1832 
1833 /// Use this to get a StringMap to all registered named options
1834 /// (e.g. -help). Note \p Map Should be an empty StringMap.
1835 ///
1836 /// \return A reference to the StringMap used by the cl APIs to parse options.
1837 ///
1838 /// Access to unnamed arguments (i.e. positional) are not provided because
1839 /// it is expected that the client already has access to these.
1840 ///
1841 /// Typical usage:
1842 /// \code
1843 /// main(int argc,char* argv[]) {
1844 /// StringMap<llvm::cl::Option*> &opts = llvm::cl::getRegisteredOptions();
1845 /// assert(opts.count("help") == 1)
1846 /// opts["help"]->setDescription("Show alphabetical help information")
1847 /// // More code
1848 /// llvm::cl::ParseCommandLineOptions(argc,argv);
1849 /// //More code
1850 /// }
1851 /// \endcode
1852 ///
1853 /// This interface is useful for modifying options in libraries that are out of
1854 /// the control of the client. The options should be modified before calling
1855 /// llvm::cl::ParseCommandLineOptions().
1856 ///
1857 /// Hopefully this API can be deprecated soon. Any situation where options need
1858 /// to be modified by tools or libraries should be handled by sane APIs rather
1859 /// than just handing around a global list.
1860 StringMap<Option *> &getRegisteredOptions(SubCommand &Sub = *TopLevelSubCommand);
1861 
1862 /// Use this to get all registered SubCommands from the provided parser.
1863 ///
1864 /// \return A range of all SubCommand pointers registered with the parser.
1865 ///
1866 /// Typical usage:
1867 /// \code
1868 /// main(int argc, char* argv[]) {
1869 ///   llvm::cl::ParseCommandLineOptions(argc, argv);
1870 ///   for (auto* S : llvm::cl::getRegisteredSubcommands()) {
1871 ///     if (*S) {
1872 ///       std::cout << "Executing subcommand: " << S->getName() << std::endl;
1873 ///       // Execute some function based on the name...
1874 ///     }
1875 ///   }
1876 /// }
1877 /// \endcode
1878 ///
1879 /// This interface is useful for defining subcommands in libraries and
1880 /// the dispatch from a single point (like in the main function).
1881 iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
1882 getRegisteredSubcommands();
1883 
1884 //===----------------------------------------------------------------------===//
1885 // Standalone command line processing utilities.
1886 //
1887 
1888 /// Tokenizes a command line that can contain escapes and quotes.
1889 //
1890 /// The quoting rules match those used by GCC and other tools that use
1891 /// libiberty's buildargv() or expandargv() utilities, and do not match bash.
1892 /// They differ from buildargv() on treatment of backslashes that do not escape
1893 /// a special character to make it possible to accept most Windows file paths.
1894 ///
1895 /// \param [in] Source The string to be split on whitespace with quotes.
1896 /// \param [in] Saver Delegates back to the caller for saving parsed strings.
1897 /// \param [in] MarkEOLs true if tokenizing a response file and you want end of
1898 /// lines and end of the response file to be marked with a nullptr string.
1899 /// \param [out] NewArgv All parsed strings are appended to NewArgv.
1900 void TokenizeGNUCommandLine(StringRef Source, StringSaver &Saver,
1901                             SmallVectorImpl<const char *> &NewArgv,
1902                             bool MarkEOLs = false);
1903 
1904 /// Tokenizes a Windows command line which may contain quotes and escaped
1905 /// quotes.
1906 ///
1907 /// See MSDN docs for CommandLineToArgvW for information on the quoting rules.
1908 /// http://msdn.microsoft.com/en-us/library/windows/desktop/17w5ykft(v=vs.85).aspx
1909 ///
1910 /// \param [in] Source The string to be split on whitespace with quotes.
1911 /// \param [in] Saver Delegates back to the caller for saving parsed strings.
1912 /// \param [in] MarkEOLs true if tokenizing a response file and you want end of
1913 /// lines and end of the response file to be marked with a nullptr string.
1914 /// \param [out] NewArgv All parsed strings are appended to NewArgv.
1915 void TokenizeWindowsCommandLine(StringRef Source, StringSaver &Saver,
1916                                 SmallVectorImpl<const char *> &NewArgv,
1917                                 bool MarkEOLs = false);
1918 
1919 /// String tokenization function type.  Should be compatible with either
1920 /// Windows or Unix command line tokenizers.
1921 using TokenizerCallback = void (*)(StringRef Source, StringSaver &Saver,
1922                                    SmallVectorImpl<const char *> &NewArgv,
1923                                    bool MarkEOLs);
1924 
1925 /// Tokenizes content of configuration file.
1926 ///
1927 /// \param [in] Source The string representing content of config file.
1928 /// \param [in] Saver Delegates back to the caller for saving parsed strings.
1929 /// \param [out] NewArgv All parsed strings are appended to NewArgv.
1930 /// \param [in] MarkEOLs Added for compatibility with TokenizerCallback.
1931 ///
1932 /// It works like TokenizeGNUCommandLine with ability to skip comment lines.
1933 ///
1934 void tokenizeConfigFile(StringRef Source, StringSaver &Saver,
1935                         SmallVectorImpl<const char *> &NewArgv,
1936                         bool MarkEOLs = false);
1937 
1938 /// Reads command line options from the given configuration file.
1939 ///
1940 /// \param [in] CfgFileName Path to configuration file.
1941 /// \param [in] Saver  Objects that saves allocated strings.
1942 /// \param [out] Argv Array to which the read options are added.
1943 /// \return true if the file was successfully read.
1944 ///
1945 /// It reads content of the specified file, tokenizes it and expands "@file"
1946 /// commands resolving file names in them relative to the directory where
1947 /// CfgFilename resides.
1948 ///
1949 bool readConfigFile(StringRef CfgFileName, StringSaver &Saver,
1950                     SmallVectorImpl<const char *> &Argv);
1951 
1952 /// Expand response files on a command line recursively using the given
1953 /// StringSaver and tokenization strategy.  Argv should contain the command line
1954 /// before expansion and will be modified in place. If requested, Argv will
1955 /// also be populated with nullptrs indicating where each response file line
1956 /// ends, which is useful for the "/link" argument that needs to consume all
1957 /// remaining arguments only until the next end of line, when in a response
1958 /// file.
1959 ///
1960 /// \param [in] Saver Delegates back to the caller for saving parsed strings.
1961 /// \param [in] Tokenizer Tokenization strategy. Typically Unix or Windows.
1962 /// \param [in,out] Argv Command line into which to expand response files.
1963 /// \param [in] MarkEOLs Mark end of lines and the end of the response file
1964 /// with nullptrs in the Argv vector.
1965 /// \param [in] RelativeNames true if names of nested response files must be
1966 /// resolved relative to including file.
1967 /// \return true if all @files were expanded successfully or there were none.
1968 bool ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
1969                          SmallVectorImpl<const char *> &Argv,
1970                          bool MarkEOLs = false, bool RelativeNames = false);
1971 
1972 /// Mark all options not part of this category as cl::ReallyHidden.
1973 ///
1974 /// \param Category the category of options to keep displaying
1975 ///
1976 /// Some tools (like clang-format) like to be able to hide all options that are
1977 /// not specific to the tool. This function allows a tool to specify a single
1978 /// option category to display in the -help output.
1979 void HideUnrelatedOptions(cl::OptionCategory &Category,
1980                           SubCommand &Sub = *TopLevelSubCommand);
1981 
1982 /// Mark all options not part of the categories as cl::ReallyHidden.
1983 ///
1984 /// \param Categories the categories of options to keep displaying.
1985 ///
1986 /// Some tools (like clang-format) like to be able to hide all options that are
1987 /// not specific to the tool. This function allows a tool to specify a single
1988 /// option category to display in the -help output.
1989 void HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
1990                           SubCommand &Sub = *TopLevelSubCommand);
1991 
1992 /// Reset all command line options to a state that looks as if they have
1993 /// never appeared on the command line.  This is useful for being able to parse
1994 /// a command line multiple times (especially useful for writing tests).
1995 void ResetAllOptionOccurrences();
1996 
1997 /// Reset the command line parser back to its initial state.  This
1998 /// removes
1999 /// all options, categories, and subcommands and returns the parser to a state
2000 /// where no options are supported.
2001 void ResetCommandLineParser();
2002 
2003 /// Parses `Arg` into the option handler `Handler`.
2004 bool ProvidePositionalOption(Option *Handler, StringRef Arg, int i);
2005 
2006 } // end namespace cl
2007 
2008 } // end namespace llvm
2009 
2010 #endif // LLVM_SUPPORT_COMMANDLINE_H
2011