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/StringSaver.h"
33	#include "llvm/Support/raw_ostream.h"
34	#include <cassert>
35	#include <climits>
36	#include <cstddef>
37	#include <functional>
38	#include <initializer_list>
39	#include <string>
40	#include <type_traits>
41	#include <vector>
42
43	namespace llvm {
44
45	namespace vfs {
46	class FileSystem;
47	}
48
49	class StringSaver;
50
51	/// This namespace contains all of the command line option processing machinery.
52	/// It is intentionally a short name to make qualified usage concise.
53	namespace cl {
54
55	//===----------------------------------------------------------------------===//
56	// Command line option processing entry point.
57	//
58	// Returns true on success. Otherwise, this will print the error message to
59	// stderr and exit if \p Errs is not set (nullptr by default), or print the
60	// error message to \p Errs and return false if \p Errs is provided.
61	//
62	// If EnvVar is not nullptr, command-line options are also parsed from the
63	// environment variable named by EnvVar. Precedence is given to occurrences
64	// from argv. This precedence is currently implemented by parsing argv after
65	// the environment variable, so it is only implemented correctly for options
66	// that give precedence to later occurrences. If your program supports options
67	// that give precedence to earlier occurrences, you will need to extend this
68	// function to support it correctly.
69	bool ParseCommandLineOptions(int argc, const char *const *argv,
70	StringRef Overview = "",
71	raw_ostream *Errs = nullptr,
72	const char *EnvVar = nullptr,
73	bool LongOptionsUseDoubleDash = false);
74
75	// Function pointer type for printing version information.
76	using VersionPrinterTy = std::function<void(raw_ostream &)>;
77
78	///===---------------------------------------------------------------------===//
79	/// Override the default (LLVM specific) version printer used to print out the
80	/// version when --version is given on the command line. This allows other
81	/// systems using the CommandLine utilities to print their own version string.
82	void SetVersionPrinter(VersionPrinterTy func);
83
84	///===---------------------------------------------------------------------===//
85	/// Add an extra printer to use in addition to the default one. This can be
86	/// called multiple times, and each time it adds a new function to the list
87	/// which will be called after the basic LLVM version printing is complete.
88	/// Each can then add additional information specific to the tool.
89	void AddExtraVersionPrinter(VersionPrinterTy func);
90
91	// Print option values.
92	// With -print-options print the difference between option values and defaults.
93	// With -print-all-options print all option values.
94	// (Currently not perfect, but best-effort.)
95	void PrintOptionValues();
96
97	// Forward declaration - AddLiteralOption needs to be up here to make gcc happy.
98	class Option;
99
100	/// Adds a new option for parsing and provides the option it refers to.
101	///
102	/// \param O pointer to the option
103	/// \param Name the string name for the option to handle during parsing
104	///
105	/// Literal options are used by some parsers to register special option values.
106	/// This is how the PassNameParser registers pass names for opt.
107	void AddLiteralOption(Option &O, StringRef Name);
108
109	//===----------------------------------------------------------------------===//
110	// Flags permitted to be passed to command line arguments
111	//
112
113	enum NumOccurrencesFlag { // Flags for the number of occurrences allowed
114	Optional = 0x00, // Zero or One occurrence
115	ZeroOrMore = 0x01, // Zero or more occurrences allowed
116	Required = 0x02, // One occurrence required
117	OneOrMore = 0x03, // One or more occurrences required
118
119	// Indicates that this option is fed anything that follows the last positional
120	// argument required by the application (it is an error if there are zero
121	// positional arguments, and a ConsumeAfter option is used).
122	// Thus, for example, all arguments to LLI are processed until a filename is
123	// found. Once a filename is found, all of the succeeding arguments are
124	// passed, unprocessed, to the ConsumeAfter option.
125	//
126	ConsumeAfter = 0x04
127	};
128
129	enum ValueExpected { // Is a value required for the option?
130	// zero reserved for the unspecified value
131	ValueOptional = 0x01, // The value can appear... or not
132	ValueRequired = 0x02, // The value is required to appear!
133	ValueDisallowed = 0x03 // A value may not be specified (for flags)
134	};
135
136	enum OptionHidden { // Control whether -help shows this option
137	NotHidden = 0x00, // Option included in -help & -help-hidden
138	Hidden = 0x01, // -help doesn't, but -help-hidden does
139	ReallyHidden = 0x02 // Neither -help nor -help-hidden show this arg
140	};
141
142	// This controls special features that the option might have that cause it to be
143	// parsed differently...
144	//
145	// Prefix - This option allows arguments that are otherwise unrecognized to be
146	// matched by options that are a prefix of the actual value. This is useful for
147	// cases like a linker, where options are typically of the form '-lfoo' or
148	// '-L../../include' where -l or -L are the actual flags. When prefix is
149	// enabled, and used, the value for the flag comes from the suffix of the
150	// argument.
151	//
152	// AlwaysPrefix - Only allow the behavior enabled by the Prefix flag and reject
153	// the Option=Value form.
154	//
155
156	enum FormattingFlags {
157	NormalFormatting = 0x00, // Nothing special
158	Positional = 0x01, // Is a positional argument, no '-' required
159	Prefix = 0x02, // Can this option directly prefix its value?
160	AlwaysPrefix = 0x03 // Can this option only directly prefix its value?
161	};
162
163	enum MiscFlags { // Miscellaneous flags to adjust argument
164	CommaSeparated = 0x01, // Should this cl::list split between commas?
165	PositionalEatsArgs = 0x02, // Should this positional cl::list eat -args?
166	Sink = 0x04, // Should this cl::list eat all unknown options?
167
168	// Can this option group with other options?
169	// If this is enabled, multiple letter options are allowed to bunch together
170	// with only a single hyphen for the whole group. This allows emulation
171	// of the behavior that ls uses for example: ls -la === ls -l -a
172	Grouping = 0x08,
173
174	// Default option
175	DefaultOption = 0x10
176	};
177
178	//===----------------------------------------------------------------------===//
179	//
180	class OptionCategory {
181	private:
182	StringRef const Name;
183	StringRef const Description;
184
185	void registerCategory();
186
187	public:
188	OptionCategory(StringRef const Name,
189	StringRef const Description = "")
190	: Name(Name), Description(Description) {
191	registerCategory();
192	}
193
194	StringRef getName() const { return Name; }
195	StringRef getDescription() const { return Description; }
196	};
197
198	// The general Option Category (used as default category).
199	OptionCategory &getGeneralCategory();
200
201	//===----------------------------------------------------------------------===//
202	//
203	class SubCommand {
204	private:
205	StringRef Name;
206	StringRef Description;
207
208	protected:
209	void registerSubCommand();
210	void unregisterSubCommand();
211
212	public:
213	SubCommand(StringRef Name, StringRef Description = "")
214	: Name(Name), Description(Description) {
215	registerSubCommand();
216	}
217	SubCommand() = default;
218
219	// Get the special subcommand representing no subcommand.
220	static SubCommand &getTopLevel();
221
222	// Get the special subcommand that can be used to put an option into all
223	// subcommands.
224	static SubCommand &getAll();
225
226	void reset();
227
228	explicit operator bool() const;
229
230	StringRef getName() const { return Name; }
231	StringRef getDescription() const { return Description; }
232
233	SmallVector<Option *, 4> PositionalOpts;
234	SmallVector<Option *, 4> SinkOpts;
235	StringMap<Option *> OptionsMap;
236
237	Option *ConsumeAfterOpt = nullptr; // The ConsumeAfter option if it exists.
238	};
239
240	// A special subcommand representing no subcommand
241	extern ManagedStatic<SubCommand> TopLevelSubCommand;
242
243	// A special subcommand that can be used to put an option into all subcommands.
244	extern ManagedStatic<SubCommand> AllSubCommands;
245
246	//===----------------------------------------------------------------------===//
247	//
248	class Option {
249	friend class alias;
250
251	// Overriden by subclasses to handle the value passed into an argument. Should
252	// return true if there was an error processing the argument and the program
253	// should exit.
254	//
255	virtual bool handleOccurrence(unsigned pos, StringRef ArgName,
256	StringRef Arg) = 0;
257
258	virtual enum ValueExpected getValueExpectedFlagDefault() const {
259	return ValueOptional;
260	}
261
262	// Out of line virtual function to provide home for the class.
263	virtual void anchor();
264
265	uint16_t NumOccurrences; // The number of times specified
266	// Occurrences, HiddenFlag, and Formatting are all enum types but to avoid
267	// problems with signed enums in bitfields.
268	uint16_t Occurrences : 3; // enum NumOccurrencesFlag
269	// not using the enum type for 'Value' because zero is an implementation
270	// detail representing the non-value
271	uint16_t Value : 2;
272	uint16_t HiddenFlag : 2; // enum OptionHidden
273	uint16_t Formatting : 2; // enum FormattingFlags
274	uint16_t Misc : 5;
275	uint16_t FullyInitialized : 1; // Has addArgument been called?
276	uint16_t Position; // Position of last occurrence of the option
277	uint16_t AdditionalVals; // Greater than 0 for multi-valued option.
278
279	public:
280	StringRef ArgStr; // The argument string itself (ex: "help", "o")
281	StringRef HelpStr; // The descriptive text message for -help
282	StringRef ValueStr; // String describing what the value of this option is
283	SmallVector<OptionCategory *, 1>
284	Categories; // The Categories this option belongs to
285	SmallPtrSet<SubCommand *, 1> Subs; // The subcommands this option belongs to.
286
287	inline enum NumOccurrencesFlag getNumOccurrencesFlag() const {
288	return (enum NumOccurrencesFlag)Occurrences;
289	}
290
291	inline enum ValueExpected getValueExpectedFlag() const {
292	return Value ? ((enum ValueExpected)Value) : getValueExpectedFlagDefault();
293	}
294
295	inline enum OptionHidden getOptionHiddenFlag() const {
296	return (enum OptionHidden)HiddenFlag;
297	}
298
299	inline enum FormattingFlags getFormattingFlag() const {
300	return (enum FormattingFlags)Formatting;
301	}
302
303	inline unsigned getMiscFlags() const { return Misc; }
304	inline unsigned getPosition() const { return Position; }
305	inline unsigned getNumAdditionalVals() const { return AdditionalVals; }
306
307	// Return true if the argstr != ""
308	bool hasArgStr() const { return !ArgStr.empty(); }
309	bool isPositional() const { return getFormattingFlag() == cl::Positional; }
310	bool isSink() const { return getMiscFlags() & cl::Sink; }
311	bool isDefaultOption() const { return getMiscFlags() & cl::DefaultOption; }
312
313	bool isConsumeAfter() const {
314	return getNumOccurrencesFlag() == cl::ConsumeAfter;
315	}
316
317	bool isInAllSubCommands() const {
318	return Subs.contains(Ptr: &SubCommand::getAll());
319	}
320
321	//-------------------------------------------------------------------------===
322	// Accessor functions set by OptionModifiers
323	//
324	void setArgStr(StringRef S);
325	void setDescription(StringRef S) { HelpStr = S; }
326	void setValueStr(StringRef S) { ValueStr = S; }
327	void setNumOccurrencesFlag(enum NumOccurrencesFlag Val) { Occurrences = Val; }
328	void setValueExpectedFlag(enum ValueExpected Val) { Value = Val; }
329	void setHiddenFlag(enum OptionHidden Val) { HiddenFlag = Val; }
330	void setFormattingFlag(enum FormattingFlags V) { Formatting = V; }
331	void setMiscFlag(enum MiscFlags M) { Misc |= M; }
332	void setPosition(unsigned pos) { Position = pos; }
333	void addCategory(OptionCategory &C);
334	void addSubCommand(SubCommand &S) { Subs.insert(Ptr: &S); }
335
336	protected:
337	explicit Option(enum NumOccurrencesFlag OccurrencesFlag,
338	enum OptionHidden Hidden)
339	: NumOccurrences(0), Occurrences(OccurrencesFlag), Value(0),
340	HiddenFlag(Hidden), Formatting(NormalFormatting), Misc(0),
341	FullyInitialized(false), Position(0), AdditionalVals(0) {
342	Categories.push_back(Elt: &getGeneralCategory());
343	}
344
345	inline void setNumAdditionalVals(unsigned n) { AdditionalVals = n; }
346
347	public:
348	virtual ~Option() = default;
349
350	// Register this argument with the commandline system.
351	//
352	void addArgument();
353
354	/// Unregisters this option from the CommandLine system.
355	///
356	/// This option must have been the last option registered.
357	/// For testing purposes only.
358	void removeArgument();
359
360	// Return the width of the option tag for printing...
361	virtual size_t getOptionWidth() const = 0;
362
363	// Print out information about this option. The to-be-maintained width is
364	// specified.
365	//
366	virtual void printOptionInfo(size_t GlobalWidth) const = 0;
367
368	virtual void printOptionValue(size_t GlobalWidth, bool Force) const = 0;
369
370	virtual void setDefault() = 0;
371
372	// Prints the help string for an option.
373	//
374	// This maintains the Indent for multi-line descriptions.
375	// FirstLineIndentedBy is the count of chars of the first line
376	// i.e. the one containing the --<option name>.
377	static void printHelpStr(StringRef HelpStr, size_t Indent,
378	size_t FirstLineIndentedBy);
379
380	// Prints the help string for an enum value.
381	//
382	// This maintains the Indent for multi-line descriptions.
383	// FirstLineIndentedBy is the count of chars of the first line
384	// i.e. the one containing the =<value>.
385	static void printEnumValHelpStr(StringRef HelpStr, size_t Indent,
386	size_t FirstLineIndentedBy);
387
388	virtual void getExtraOptionNames(SmallVectorImpl<StringRef> &) {}
389
390	// Wrapper around handleOccurrence that enforces Flags.
391	//
392	virtual bool addOccurrence(unsigned pos, StringRef ArgName, StringRef Value,
393	bool MultiArg = false);
394
395	// Prints option name followed by message. Always returns true.
396	bool error(const Twine &Message, StringRef ArgName = StringRef(), raw_ostream &Errs = llvm::errs());
397	bool error(const Twine &Message, raw_ostream &Errs) {
398	return error(Message, ArgName: StringRef(), Errs);
399	}
400
401	inline int getNumOccurrences() const { return NumOccurrences; }
402	void reset();
403	};
404
405	//===----------------------------------------------------------------------===//
406	// Command line option modifiers that can be used to modify the behavior of
407	// command line option parsers...
408	//
409
410	// Modifier to set the description shown in the -help output...
411	struct desc {
412	StringRef Desc;
413
414	desc(StringRef Str) : Desc(Str) {}
415
416	void apply(Option &O) const { O.setDescription(Desc); }
417	};
418
419	// Modifier to set the value description shown in the -help output...
420	struct value_desc {
421	StringRef Desc;
422
423	value_desc(StringRef Str) : Desc(Str) {}
424
425	void apply(Option &O) const { O.setValueStr(Desc); }
426	};
427
428	// Specify a default (initial) value for the command line argument, if the
429	// default constructor for the argument type does not give you what you want.
430	// This is only valid on "opt" arguments, not on "list" arguments.
431	template <class Ty> struct initializer {
432	const Ty &Init;
433	initializer(const Ty &Val) : Init(Val) {}
434
435	template <class Opt> void apply(Opt &O) const { O.setInitialValue(Init); }
436	};
437
438	template <class Ty> struct list_initializer {
439	ArrayRef<Ty> Inits;
440	list_initializer(ArrayRef<Ty> Vals) : Inits(Vals) {}
441
442	template <class Opt> void apply(Opt &O) const { O.setInitialValues(Inits); }
443	};
444
445	template <class Ty> initializer<Ty> init(const Ty &Val) {
446	return initializer<Ty>(Val);
447	}
448
449	template <class Ty>
450	list_initializer<Ty> list_init(ArrayRef<Ty> Vals) {
451	return list_initializer<Ty>(Vals);
452	}
453
454	// Allow the user to specify which external variable they want to store the
455	// results of the command line argument processing into, if they don't want to
456	// store it in the option itself.
457	template <class Ty> struct LocationClass {
458	Ty &Loc;
459
460	LocationClass(Ty &L) : Loc(L) {}
461
462	template <class Opt> void apply(Opt &O) const { O.setLocation(O, Loc); }
463	};
464
465	template <class Ty> LocationClass<Ty> location(Ty &L) {
466	return LocationClass<Ty>(L);
467	}
468
469	// Specify the Option category for the command line argument to belong to.
470	struct cat {
471	OptionCategory &Category;
472
473	cat(OptionCategory &c) : Category(c) {}
474
475	template <class Opt> void apply(Opt &O) const { O.addCategory(Category); }
476	};
477
478	// Specify the subcommand that this option belongs to.
479	struct sub {
480	SubCommand &Sub;
481
482	sub(SubCommand &S) : Sub(S) {}
483
484	template <class Opt> void apply(Opt &O) const { O.addSubCommand(Sub); }
485	};
486
487	// Specify a callback function to be called when an option is seen.
488	// Can be used to set other options automatically.
489	template <typename R, typename Ty> struct cb {
490	std::function<R(Ty)> CB;
491
492	cb(std::function<R(Ty)> CB) : CB(CB) {}
493
494	template <typename Opt> void apply(Opt &O) const { O.setCallback(CB); }
495	};
496
497	namespace detail {
498	template <typename F>
499	struct callback_traits : public callback_traits<decltype(&F::operator())> {};
500
501	template <typename R, typename C, typename... Args>
502	struct callback_traits<R (C::*)(Args...) const> {
503	using result_type = R;
504	using arg_type = std::tuple_element_t<0, std::tuple<Args...>>;
505	static_assert(sizeof...(Args) == 1, "callback function must have one and only one parameter");
506	static_assert(std::is_same_v<result_type, void>,
507	"callback return type must be void");
508	static_assert(std::is_lvalue_reference_v<arg_type> &&
509	std::is_const_v<std::remove_reference_t<arg_type>>,
510	"callback arg_type must be a const lvalue reference");
511	};
512	} // namespace detail
513
514	template <typename F>
515	cb<typename detail::callback_traits<F>::result_type,
516	typename detail::callback_traits<F>::arg_type>
517	callback(F CB) {
518	using result_type = typename detail::callback_traits<F>::result_type;
519	using arg_type = typename detail::callback_traits<F>::arg_type;
520	return cb<result_type, arg_type>(CB);
521	}
522
523	//===----------------------------------------------------------------------===//
524
525	// Support value comparison outside the template.
526	struct GenericOptionValue {
527	virtual bool compare(const GenericOptionValue &V) const = 0;
528
529	protected:
530	GenericOptionValue() = default;
531	GenericOptionValue(const GenericOptionValue&) = default;
532	GenericOptionValue &operator=(const GenericOptionValue &) = default;
533	~GenericOptionValue() = default;
534
535	private:
536	virtual void anchor();
537	};
538
539	template <class DataType> struct OptionValue;
540
541	// The default value safely does nothing. Option value printing is only
542	// best-effort.
543	template <class DataType, bool isClass>
544	struct OptionValueBase : public GenericOptionValue {
545	// Temporary storage for argument passing.
546	using WrapperType = OptionValue<DataType>;
547
548	bool hasValue() const { return false; }
549
550	const DataType &getValue() const { llvm_unreachable("no default value"); }
551
552	// Some options may take their value from a different data type.
553	template <class DT> void setValue(const DT & /*V*/) {}
554
555	bool compare(const DataType & /*V*/) const { return false; }
556
557	bool compare(const GenericOptionValue & /*V*/) const override {
558	return false;
559	}
560
561	protected:
562	~OptionValueBase() = default;
563	};
564
565	// Simple copy of the option value.
566	template <class DataType> class OptionValueCopy : public GenericOptionValue {
567	DataType Value;
568	bool Valid = false;
569
570	protected:
571	OptionValueCopy(const OptionValueCopy&) = default;
572	OptionValueCopy &operator=(const OptionValueCopy &) = default;
573	~OptionValueCopy() = default;
574
575	public:
576	OptionValueCopy() = default;
577
578	bool hasValue() const { return Valid; }
579
580	const DataType &getValue() const {
581	assert(Valid && "invalid option value");
582	return Value;
583	}
584
585	void setValue(const DataType &V) {
586	Valid = true;
587	Value = V;
588	}
589
590	bool compare(const DataType &V) const { return Valid && (Value != V); }
591
592	bool compare(const GenericOptionValue &V) const override {
593	const OptionValueCopy<DataType> &VC =
594	static_cast<const OptionValueCopy<DataType> &>(V);
595	if (!VC.hasValue())
596	return false;
597	return compare(VC.getValue());
598	}
599	};
600
601	// Non-class option values.
602	template <class DataType>
603	struct OptionValueBase<DataType, false> : OptionValueCopy<DataType> {
604	using WrapperType = DataType;
605
606	protected:
607	OptionValueBase() = default;
608	OptionValueBase(const OptionValueBase&) = default;
609	OptionValueBase &operator=(const OptionValueBase &) = default;
610	~OptionValueBase() = default;
611	};
612
613	// Top-level option class.
614	template <class DataType>
615	struct OptionValue final
616	: OptionValueBase<DataType, std::is_class_v<DataType>> {
617	OptionValue() = default;
618
619	OptionValue(const DataType &V) { this->setValue(V); }
620
621	// Some options may take their value from a different data type.
622	template <class DT> OptionValue<DataType> &operator=(const DT &V) {
623	this->setValue(V);
624	return *this;
625	}
626	};
627
628	// Other safe-to-copy-by-value common option types.
629	enum boolOrDefault { BOU_UNSET, BOU_TRUE, BOU_FALSE };
630	template <>
631	struct OptionValue<cl::boolOrDefault> final
632	: OptionValueCopy<cl::boolOrDefault> {
633	using WrapperType = cl::boolOrDefault;
634
635	OptionValue() = default;
636
637	OptionValue(const cl::boolOrDefault &V) { this->setValue(V); }
638
639	OptionValue<cl::boolOrDefault> &operator=(const cl::boolOrDefault &V) {
640	setValue(V);
641	return *this;
642	}
643
644	private:
645	void anchor() override;
646	};
647
648	template <>
649	struct OptionValue<std::string> final : OptionValueCopy<std::string> {
650	using WrapperType = StringRef;
651
652	OptionValue() = default;
653
654	OptionValue(const std::string &V) { this->setValue(V); }
655
656	OptionValue<std::string> &operator=(const std::string &V) {
657	setValue(V);
658	return *this;
659	}
660
661	private:
662	void anchor() override;
663	};
664
665	//===----------------------------------------------------------------------===//
666	// Enum valued command line option
667	//
668
669	// This represents a single enum value, using "int" as the underlying type.
670	struct OptionEnumValue {
671	StringRef Name;
672	int Value;
673	StringRef Description;
674	};
675
676	#define clEnumVal(ENUMVAL, DESC) \
677	llvm::cl::OptionEnumValue { #ENUMVAL, int(ENUMVAL), DESC }
678	#define clEnumValN(ENUMVAL, FLAGNAME, DESC) \
679	llvm::cl::OptionEnumValue { FLAGNAME, int(ENUMVAL), DESC }
680
681	// For custom data types, allow specifying a group of values together as the
682	// values that go into the mapping that the option handler uses.
683	//
684	class ValuesClass {
685	// Use a vector instead of a map, because the lists should be short,
686	// the overhead is less, and most importantly, it keeps them in the order
687	// inserted so we can print our option out nicely.
688	SmallVector<OptionEnumValue, 4> Values;
689
690	public:
691	ValuesClass(std::initializer_list<OptionEnumValue> Options)
692	: Values(Options) {}
693
694	template <class Opt> void apply(Opt &O) const {
695	for (const auto &Value : Values)
696	O.getParser().addLiteralOption(Value.Name, Value.Value,
697	Value.Description);
698	}
699	};
700
701	/// Helper to build a ValuesClass by forwarding a variable number of arguments
702	/// as an initializer list to the ValuesClass constructor.
703	template <typename... OptsTy> ValuesClass values(OptsTy... Options) {
704	return ValuesClass({Options...});
705	}
706
707	//===----------------------------------------------------------------------===//
708	// Parameterizable parser for different data types. By default, known data types
709	// (string, int, bool) have specialized parsers, that do what you would expect.
710	// The default parser, used for data types that are not built-in, uses a mapping
711	// table to map specific options to values, which is used, among other things,
712	// to handle enum types.
713
714	//--------------------------------------------------
715	// This class holds all the non-generic code that we do not need replicated for
716	// every instance of the generic parser. This also allows us to put stuff into
717	// CommandLine.cpp
718	//
719	class generic_parser_base {
720	protected:
721	class GenericOptionInfo {
722	public:
723	GenericOptionInfo(StringRef name, StringRef helpStr)
724	: Name(name), HelpStr(helpStr) {}
725	StringRef Name;
726	StringRef HelpStr;
727	};
728
729	public:
730	generic_parser_base(Option &O) : Owner(O) {}
731
732	virtual ~generic_parser_base() = default;
733	// Base class should have virtual-destructor
734
735	// Virtual function implemented by generic subclass to indicate how many
736	// entries are in Values.
737	//
738	virtual unsigned getNumOptions() const = 0;
739
740	// Return option name N.
741	virtual StringRef getOption(unsigned N) const = 0;
742
743	// Return description N
744	virtual StringRef getDescription(unsigned N) const = 0;
745
746	// Return the width of the option tag for printing...
747	virtual size_t getOptionWidth(const Option &O) const;
748
749	virtual const GenericOptionValue &getOptionValue(unsigned N) const = 0;
750
751	// Print out information about this option. The to-be-maintained width is
752	// specified.
753	//
754	virtual void printOptionInfo(const Option &O, size_t GlobalWidth) const;
755
756	void printGenericOptionDiff(const Option &O, const GenericOptionValue &V,
757	const GenericOptionValue &Default,
758	size_t GlobalWidth) const;
759
760	// Print the value of an option and it's default.
761	//
762	// Template definition ensures that the option and default have the same
763	// DataType (via the same AnyOptionValue).
764	template <class AnyOptionValue>
765	void printOptionDiff(const Option &O, const AnyOptionValue &V,
766	const AnyOptionValue &Default,
767	size_t GlobalWidth) const {
768	printGenericOptionDiff(O, V, Default, GlobalWidth);
769	}
770
771	void initialize() {}
772
773	void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) {
774	// If there has been no argstr specified, that means that we need to add an
775	// argument for every possible option. This ensures that our options are
776	// vectored to us.
777	if (!Owner.hasArgStr())
778	for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
779	OptionNames.push_back(Elt: getOption(N: i));
780	}
781
782	enum ValueExpected getValueExpectedFlagDefault() const {
783	// If there is an ArgStr specified, then we are of the form:
784	//
785	// -opt=O2 or -opt O2 or -optO2
786	//
787	// In which case, the value is required. Otherwise if an arg str has not
788	// been specified, we are of the form:
789	//
790	// -O2 or O2 or -la (where -l and -a are separate options)
791	//
792	// If this is the case, we cannot allow a value.
793	//
794	if (Owner.hasArgStr())
795	return ValueRequired;
796	else
797	return ValueDisallowed;
798	}
799
800	// Return the option number corresponding to the specified
801	// argument string. If the option is not found, getNumOptions() is returned.
802	//
803	unsigned findOption(StringRef Name);
804
805	protected:
806	Option &Owner;
807	};
808
809	// Default parser implementation - This implementation depends on having a
810	// mapping of recognized options to values of some sort. In addition to this,
811	// each entry in the mapping also tracks a help message that is printed with the
812	// command line option for -help. Because this is a simple mapping parser, the
813	// data type can be any unsupported type.
814	//
815	template <class DataType> class parser : public generic_parser_base {
816	protected:
817	class OptionInfo : public GenericOptionInfo {
818	public:
819	OptionInfo(StringRef name, DataType v, StringRef helpStr)
820	: GenericOptionInfo(name, helpStr), V(v) {}
821
822	OptionValue<DataType> V;
823	};
824	SmallVector<OptionInfo, 8> Values;
825
826	public:
827	parser(Option &O) : generic_parser_base(O) {}
828
829	using parser_data_type = DataType;
830
831	// Implement virtual functions needed by generic_parser_base
832	unsigned getNumOptions() const override { return unsigned(Values.size()); }
833	StringRef getOption(unsigned N) const override { return Values[N].Name; }
834	StringRef getDescription(unsigned N) const override {
835	return Values[N].HelpStr;
836	}
837
838	// Return the value of option name N.
839	const GenericOptionValue &getOptionValue(unsigned N) const override {
840	return Values[N].V;
841	}
842
843	// Return true on error.
844	bool parse(Option &O, StringRef ArgName, StringRef Arg, DataType &V) {
845	StringRef ArgVal;
846	if (Owner.hasArgStr())
847	ArgVal = Arg;
848	else
849	ArgVal = ArgName;
850
851	for (size_t i = 0, e = Values.size(); i != e; ++i)
852	if (Values[i].Name == ArgVal) {
853	V = Values[i].V.getValue();
854	return false;
855	}
856
857	return O.error(Message: "Cannot find option named '" + ArgVal + "'!");
858	}
859
860	/// Add an entry to the mapping table.
861	///
862	template <class DT>
863	void addLiteralOption(StringRef Name, const DT &V, StringRef HelpStr) {
864	assert(findOption(Name) == Values.size() && "Option already exists!");
865	OptionInfo X(Name, static_cast<DataType>(V), HelpStr);
866	Values.push_back(X);
867	AddLiteralOption(Owner, Name);
868	}
869
870	/// Remove the specified option.
871	///
872	void removeLiteralOption(StringRef Name) {
873	unsigned N = findOption(Name);
874	assert(N != Values.size() && "Option not found!");
875	Values.erase(Values.begin() + N);
876	}
877	};
878
879	//--------------------------------------------------
880	// Super class of parsers to provide boilerplate code
881	//
882	class basic_parser_impl { // non-template implementation of basic_parser<t>
883	public:
884	basic_parser_impl(Option &) {}
885
886	virtual ~basic_parser_impl() = default;
887
888	enum ValueExpected getValueExpectedFlagDefault() const {
889	return ValueRequired;
890	}
891
892	void getExtraOptionNames(SmallVectorImpl<StringRef> &) {}
893
894	void initialize() {}
895
896	// Return the width of the option tag for printing...
897	size_t getOptionWidth(const Option &O) const;
898
899	// Print out information about this option. The to-be-maintained width is
900	// specified.
901	//
902	void printOptionInfo(const Option &O, size_t GlobalWidth) const;
903
904	// Print a placeholder for options that don't yet support printOptionDiff().
905	void printOptionNoValue(const Option &O, size_t GlobalWidth) const;
906
907	// Overload in subclass to provide a better default value.
908	virtual StringRef getValueName() const { return "value"; }
909
910	// An out-of-line virtual method to provide a 'home' for this class.
911	virtual void anchor();
912
913	protected:
914	// A helper for basic_parser::printOptionDiff.
915	void printOptionName(const Option &O, size_t GlobalWidth) const;
916	};
917
918	// The real basic parser is just a template wrapper that provides a typedef for
919	// the provided data type.
920	//
921	template <class DataType> class basic_parser : public basic_parser_impl {
922	public:
923	using parser_data_type = DataType;
924	using OptVal = OptionValue<DataType>;
925
926	basic_parser(Option &O) : basic_parser_impl(O) {}
927	};
928
929	//--------------------------------------------------
930
931	extern template class basic_parser<bool>;
932
933	template <> class parser<bool> : public basic_parser<bool> {
934	public:
935	parser(Option &O) : basic_parser(O) {}
936
937	// Return true on error.
938	bool parse(Option &O, StringRef ArgName, StringRef Arg, bool &Val);
939
940	void initialize() {}
941
942	enum ValueExpected getValueExpectedFlagDefault() const {
943	return ValueOptional;
944	}
945
946	// Do not print =<value> at all.
947	StringRef getValueName() const override { return StringRef(); }
948
949	void printOptionDiff(const Option &O, bool V, OptVal Default,
950	size_t GlobalWidth) const;
951
952	// An out-of-line virtual method to provide a 'home' for this class.
953	void anchor() override;
954	};
955
956	//--------------------------------------------------
957
958	extern template class basic_parser<boolOrDefault>;
959
960	template <> class parser<boolOrDefault> : public basic_parser<boolOrDefault> {
961	public:
962	parser(Option &O) : basic_parser(O) {}
963
964	// Return true on error.
965	bool parse(Option &O, StringRef ArgName, StringRef Arg, boolOrDefault &Val);
966
967	enum ValueExpected getValueExpectedFlagDefault() const {
968	return ValueOptional;
969	}
970
971	// Do not print =<value> at all.
972	StringRef getValueName() const override { return StringRef(); }
973
974	void printOptionDiff(const Option &O, boolOrDefault V, OptVal Default,
975	size_t GlobalWidth) const;
976
977	// An out-of-line virtual method to provide a 'home' for this class.
978	void anchor() override;
979	};
980
981	//--------------------------------------------------
982
983	extern template class basic_parser<int>;
984
985	template <> class parser<int> : public basic_parser<int> {
986	public:
987	parser(Option &O) : basic_parser(O) {}
988
989	// Return true on error.
990	bool parse(Option &O, StringRef ArgName, StringRef Arg, int &Val);
991
992	// Overload in subclass to provide a better default value.
993	StringRef getValueName() const override { return "int"; }
994
995	void printOptionDiff(const Option &O, int V, OptVal Default,
996	size_t GlobalWidth) const;
997
998	// An out-of-line virtual method to provide a 'home' for this class.
999	void anchor() override;
1000	};
1001
1002	//--------------------------------------------------
1003
1004	extern template class basic_parser<long>;
1005
1006	template <> class parser<long> final : public basic_parser<long> {
1007	public:
1008	parser(Option &O) : basic_parser(O) {}
1009
1010	// Return true on error.
1011	bool parse(Option &O, StringRef ArgName, StringRef Arg, long &Val);
1012
1013	// Overload in subclass to provide a better default value.
1014	StringRef getValueName() const override { return "long"; }
1015
1016	void printOptionDiff(const Option &O, long V, OptVal Default,
1017	size_t GlobalWidth) const;
1018
1019	// An out-of-line virtual method to provide a 'home' for this class.
1020	void anchor() override;
1021	};
1022
1023	//--------------------------------------------------
1024
1025	extern template class basic_parser<long long>;
1026
1027	template <> class parser<long long> : public basic_parser<long long> {
1028	public:
1029	parser(Option &O) : basic_parser(O) {}
1030
1031	// Return true on error.
1032	bool parse(Option &O, StringRef ArgName, StringRef Arg, long long &Val);
1033
1034	// Overload in subclass to provide a better default value.
1035	StringRef getValueName() const override { return "long"; }
1036
1037	void printOptionDiff(const Option &O, long long V, OptVal Default,
1038	size_t GlobalWidth) const;
1039
1040	// An out-of-line virtual method to provide a 'home' for this class.
1041	void anchor() override;
1042	};
1043
1044	//--------------------------------------------------
1045
1046	extern template class basic_parser<unsigned>;
1047
1048	template <> class parser<unsigned> : public basic_parser<unsigned> {
1049	public:
1050	parser(Option &O) : basic_parser(O) {}
1051
1052	// Return true on error.
1053	bool parse(Option &O, StringRef ArgName, StringRef Arg, unsigned &Val);
1054
1055	// Overload in subclass to provide a better default value.
1056	StringRef getValueName() const override { return "uint"; }
1057
1058	void printOptionDiff(const Option &O, unsigned 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	//--------------------------------------------------
1066
1067	extern template class basic_parser<unsigned long>;
1068
1069	template <>
1070	class parser<unsigned long> final : public basic_parser<unsigned long> {
1071	public:
1072	parser(Option &O) : basic_parser(O) {}
1073
1074	// Return true on error.
1075	bool parse(Option &O, StringRef ArgName, StringRef Arg, unsigned long &Val);
1076
1077	// Overload in subclass to provide a better default value.
1078	StringRef getValueName() const override { return "ulong"; }
1079
1080	void printOptionDiff(const Option &O, unsigned long V, OptVal Default,
1081	size_t GlobalWidth) const;
1082
1083	// An out-of-line virtual method to provide a 'home' for this class.
1084	void anchor() override;
1085	};
1086
1087	//--------------------------------------------------
1088
1089	extern template class basic_parser<unsigned long long>;
1090
1091	template <>
1092	class parser<unsigned long long> : public basic_parser<unsigned long long> {
1093	public:
1094	parser(Option &O) : basic_parser(O) {}
1095
1096	// Return true on error.
1097	bool parse(Option &O, StringRef ArgName, StringRef Arg,
1098	unsigned long long &Val);
1099
1100	// Overload in subclass to provide a better default value.
1101	StringRef getValueName() const override { return "ulong"; }
1102
1103	void printOptionDiff(const Option &O, unsigned long long V, OptVal Default,
1104	size_t GlobalWidth) const;
1105
1106	// An out-of-line virtual method to provide a 'home' for this class.
1107	void anchor() override;
1108	};
1109
1110	//--------------------------------------------------
1111
1112	extern template class basic_parser<double>;
1113
1114	template <> class parser<double> : public basic_parser<double> {
1115	public:
1116	parser(Option &O) : basic_parser(O) {}
1117
1118	// Return true on error.
1119	bool parse(Option &O, StringRef ArgName, StringRef Arg, double &Val);
1120
1121	// Overload in subclass to provide a better default value.
1122	StringRef getValueName() const override { return "number"; }
1123
1124	void printOptionDiff(const Option &O, double V, OptVal Default,
1125	size_t GlobalWidth) const;
1126
1127	// An out-of-line virtual method to provide a 'home' for this class.
1128	void anchor() override;
1129	};
1130
1131	//--------------------------------------------------
1132
1133	extern template class basic_parser<float>;
1134
1135	template <> class parser<float> : public basic_parser<float> {
1136	public:
1137	parser(Option &O) : basic_parser(O) {}
1138
1139	// Return true on error.
1140	bool parse(Option &O, StringRef ArgName, StringRef Arg, float &Val);
1141
1142	// Overload in subclass to provide a better default value.
1143	StringRef getValueName() const override { return "number"; }
1144
1145	void printOptionDiff(const Option &O, float V, OptVal Default,
1146	size_t GlobalWidth) const;
1147
1148	// An out-of-line virtual method to provide a 'home' for this class.
1149	void anchor() override;
1150	};
1151
1152	//--------------------------------------------------
1153
1154	extern template class basic_parser<std::string>;
1155
1156	template <> class parser<std::string> : public basic_parser<std::string> {
1157	public:
1158	parser(Option &O) : basic_parser(O) {}
1159
1160	// Return true on error.
1161	bool parse(Option &, StringRef, StringRef Arg, std::string &Value) {
1162	Value = Arg.str();
1163	return false;
1164	}
1165
1166	// Overload in subclass to provide a better default value.
1167	StringRef getValueName() const override { return "string"; }
1168
1169	void printOptionDiff(const Option &O, StringRef V, const OptVal &Default,
1170	size_t GlobalWidth) const;
1171
1172	// An out-of-line virtual method to provide a 'home' for this class.
1173	void anchor() override;
1174	};
1175
1176	//--------------------------------------------------
1177
1178	extern template class basic_parser<char>;
1179
1180	template <> class parser<char> : public basic_parser<char> {
1181	public:
1182	parser(Option &O) : basic_parser(O) {}
1183
1184	// Return true on error.
1185	bool parse(Option &, StringRef, StringRef Arg, char &Value) {
1186	Value = Arg[0];
1187	return false;
1188	}
1189
1190	// Overload in subclass to provide a better default value.
1191	StringRef getValueName() const override { return "char"; }
1192
1193	void printOptionDiff(const Option &O, char V, OptVal Default,
1194	size_t GlobalWidth) const;
1195
1196	// An out-of-line virtual method to provide a 'home' for this class.
1197	void anchor() override;
1198	};
1199
1200	//--------------------------------------------------
1201	// This collection of wrappers is the intermediary between class opt and class
1202	// parser to handle all the template nastiness.
1203
1204	// This overloaded function is selected by the generic parser.
1205	template <class ParserClass, class DT>
1206	void printOptionDiff(const Option &O, const generic_parser_base &P, const DT &V,
1207	const OptionValue<DT> &Default, size_t GlobalWidth) {
1208	OptionValue<DT> OV = V;
1209	P.printOptionDiff(O, OV, Default, GlobalWidth);
1210	}
1211
1212	// This is instantiated for basic parsers when the parsed value has a different
1213	// type than the option value. e.g. HelpPrinter.
1214	template <class ParserDT, class ValDT> struct OptionDiffPrinter {
1215	void print(const Option &O, const parser<ParserDT> &P, const ValDT & /*V*/,
1216	const OptionValue<ValDT> & /*Default*/, size_t GlobalWidth) {
1217	P.printOptionNoValue(O, GlobalWidth);
1218	}
1219	};
1220
1221	// This is instantiated for basic parsers when the parsed value has the same
1222	// type as the option value.
1223	template <class DT> struct OptionDiffPrinter<DT, DT> {
1224	void print(const Option &O, const parser<DT> &P, const DT &V,
1225	const OptionValue<DT> &Default, size_t GlobalWidth) {
1226	P.printOptionDiff(O, V, Default, GlobalWidth);
1227	}
1228	};
1229
1230	// This overloaded function is selected by the basic parser, which may parse a
1231	// different type than the option type.
1232	template <class ParserClass, class ValDT>
1233	void printOptionDiff(
1234	const Option &O,
1235	const basic_parser<typename ParserClass::parser_data_type> &P,
1236	const ValDT &V, const OptionValue<ValDT> &Default, size_t GlobalWidth) {
1237
1238	OptionDiffPrinter<typename ParserClass::parser_data_type, ValDT> printer;
1239	printer.print(O, static_cast<const ParserClass &>(P), V, Default,
1240	GlobalWidth);
1241	}
1242
1243	//===----------------------------------------------------------------------===//
1244	// This class is used because we must use partial specialization to handle
1245	// literal string arguments specially (const char* does not correctly respond to
1246	// the apply method). Because the syntax to use this is a pain, we have the
1247	// 'apply' method below to handle the nastiness...
1248	//
1249	template <class Mod> struct applicator {
1250	template <class Opt> static void opt(const Mod &M, Opt &O) { M.apply(O); }
1251	};
1252
1253	// Handle const char* as a special case...
1254	template <unsigned n> struct applicator<char[n]> {
1255	template <class Opt> static void opt(StringRef Str, Opt &O) {
1256	O.setArgStr(Str);
1257	}
1258	};
1259	template <unsigned n> struct applicator<const char[n]> {
1260	template <class Opt> static void opt(StringRef Str, Opt &O) {
1261	O.setArgStr(Str);
1262	}
1263	};
1264	template <> struct applicator<StringRef > {
1265	template <class Opt> static void opt(StringRef Str, Opt &O) {
1266	O.setArgStr(Str);
1267	}
1268	};
1269
1270	template <> struct applicator<NumOccurrencesFlag> {
1271	static void opt(NumOccurrencesFlag N, Option &O) {
1272	O.setNumOccurrencesFlag(N);
1273	}
1274	};
1275
1276	template <> struct applicator<ValueExpected> {
1277	static void opt(ValueExpected VE, Option &O) { O.setValueExpectedFlag(VE); }
1278	};
1279
1280	template <> struct applicator<OptionHidden> {
1281	static void opt(OptionHidden OH, Option &O) { O.setHiddenFlag(OH); }
1282	};
1283
1284	template <> struct applicator<FormattingFlags> {
1285	static void opt(FormattingFlags FF, Option &O) { O.setFormattingFlag(FF); }
1286	};
1287
1288	template <> struct applicator<MiscFlags> {
1289	static void opt(MiscFlags MF, Option &O) {
1290	assert((MF != Grouping || O.ArgStr.size() == 1) &&
1291	"cl::Grouping can only apply to single character Options.");
1292	O.setMiscFlag(MF);
1293	}
1294	};
1295
1296	// Apply modifiers to an option in a type safe way.
1297	template <class Opt, class Mod, class... Mods>
1298	void apply(Opt *O, const Mod &M, const Mods &... Ms) {
1299	applicator<Mod>::opt(M, *O);
1300	apply(O, Ms...);
1301	}
1302
1303	template <class Opt, class Mod> void apply(Opt *O, const Mod &M) {
1304	applicator<Mod>::opt(M, *O);
1305	}
1306
1307	//===----------------------------------------------------------------------===//
1308	// Default storage class definition: external storage. This implementation
1309	// assumes the user will specify a variable to store the data into with the
1310	// cl::location(x) modifier.
1311	//
1312	template <class DataType, bool ExternalStorage, bool isClass>
1313	class opt_storage {
1314	DataType *Location = nullptr; // Where to store the object...
1315	OptionValue<DataType> Default;
1316
1317	void check_location() const {
1318	assert(Location && "cl::location(...) not specified for a command "
1319	"line option with external storage, "
1320	"or cl::init specified before cl::location()!!");
1321	}
1322
1323	public:
1324	opt_storage() = default;
1325
1326	bool setLocation(Option &O, DataType &L) {
1327	if (Location)
1328	return O.error(Message: "cl::location(x) specified more than once!");
1329	Location = &L;
1330	Default = L;
1331	return false;
1332	}
1333
1334	template <class T> void setValue(const T &V, bool initial = false) {
1335	check_location();
1336	*Location = V;
1337	if (initial)
1338	Default = V;
1339	}
1340
1341	DataType &getValue() {
1342	check_location();
1343	return *Location;
1344	}
1345	const DataType &getValue() const {
1346	check_location();
1347	return *Location;
1348	}
1349
1350	operator DataType() const { return this->getValue(); }
1351
1352	const OptionValue<DataType> &getDefault() const { return Default; }
1353	};
1354
1355	// Define how to hold a class type object, such as a string. Since we can
1356	// inherit from a class, we do so. This makes us exactly compatible with the
1357	// object in all cases that it is used.
1358	//
1359	template <class DataType>
1360	class opt_storage<DataType, false, true> : public DataType {
1361	public:
1362	OptionValue<DataType> Default;
1363
1364	template <class T> void setValue(const T &V, bool initial = false) {
1365	DataType::operator=(V);
1366	if (initial)
1367	Default = V;
1368	}
1369
1370	DataType &getValue() { return *this; }
1371	const DataType &getValue() const { return *this; }
1372
1373	const OptionValue<DataType> &getDefault() const { return Default; }
1374	};
1375
1376	// Define a partial specialization to handle things we cannot inherit from. In
1377	// this case, we store an instance through containment, and overload operators
1378	// to get at the value.
1379	//
1380	template <class DataType> class opt_storage<DataType, false, false> {
1381	public:
1382	DataType Value;
1383	OptionValue<DataType> Default;
1384
1385	// Make sure we initialize the value with the default constructor for the
1386	// type.
1387	opt_storage() : Value(DataType()), Default() {}
1388
1389	template <class T> void setValue(const T &V, bool initial = false) {
1390	Value = V;
1391	if (initial)
1392	Default = V;
1393	}
1394	DataType &getValue() { return Value; }
1395	DataType getValue() const { return Value; }
1396
1397	const OptionValue<DataType> &getDefault() const { return Default; }
1398
1399	operator DataType() const { return getValue(); }
1400
1401	// If the datatype is a pointer, support -> on it.
1402	DataType operator->() const { return Value; }
1403	};
1404
1405	//===----------------------------------------------------------------------===//
1406	// A scalar command line option.
1407	//
1408	template <class DataType, bool ExternalStorage = false,
1409	class ParserClass = parser<DataType>>
1410	class opt
1411	: public Option,
1412	public opt_storage<DataType, ExternalStorage, std::is_class_v<DataType>> {
1413	ParserClass Parser;
1414
1415	bool handleOccurrence(unsigned pos, StringRef ArgName,
1416	StringRef Arg) override {
1417	typename ParserClass::parser_data_type Val =
1418	typename ParserClass::parser_data_type();
1419	if (Parser.parse(*this, ArgName, Arg, Val))
1420	return true; // Parse error!
1421	this->setValue(Val);
1422	this->setPosition(pos);
1423	Callback(Val);
1424	return false;
1425	}
1426
1427	enum ValueExpected getValueExpectedFlagDefault() const override {
1428	return Parser.getValueExpectedFlagDefault();
1429	}
1430
1431	void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1432	return Parser.getExtraOptionNames(OptionNames);
1433	}
1434
1435	// Forward printing stuff to the parser...
1436	size_t getOptionWidth() const override {
1437	return Parser.getOptionWidth(*this);
1438	}
1439
1440	void printOptionInfo(size_t GlobalWidth) const override {
1441	Parser.printOptionInfo(*this, GlobalWidth);
1442	}
1443
1444	void printOptionValue(size_t GlobalWidth, bool Force) const override {
1445	if (Force || this->getDefault().compare(this->getValue())) {
1446	cl::printOptionDiff<ParserClass>(*this, Parser, this->getValue(),
1447	this->getDefault(), GlobalWidth);
1448	}
1449	}
1450
1451	template <class T, class = std::enable_if_t<std::is_assignable_v<T &, T>>>
1452	void setDefaultImpl() {
1453	const OptionValue<DataType> &V = this->getDefault();
1454	if (V.hasValue())
1455	this->setValue(V.getValue());
1456	else
1457	this->setValue(T());
1458	}
1459
1460	template <class T, class = std::enable_if_t<!std::is_assignable_v<T &, T>>>
1461	void setDefaultImpl(...) {}
1462
1463	void setDefault() override { setDefaultImpl<DataType>(); }
1464
1465	void done() {
1466	addArgument();
1467	Parser.initialize();
1468	}
1469
1470	public:
1471	// Command line options should not be copyable
1472	opt(const opt &) = delete;
1473	opt &operator=(const opt &) = delete;
1474
1475	// setInitialValue - Used by the cl::init modifier...
1476	void setInitialValue(const DataType &V) { this->setValue(V, true); }
1477
1478	ParserClass &getParser() { return Parser; }
1479
1480	template <class T> DataType &operator=(const T &Val) {
1481	this->setValue(Val);
1482	Callback(Val);
1483	return this->getValue();
1484	}
1485
1486	template <class... Mods>
1487	explicit opt(const Mods &... Ms)
1488	: Option(llvm::cl::Optional, NotHidden), Parser(*this) {
1489	apply(this, Ms...);
1490	done();
1491	}
1492
1493	void setCallback(
1494	std::function<void(const typename ParserClass::parser_data_type &)> CB) {
1495	Callback = CB;
1496	}
1497
1498	std::function<void(const typename ParserClass::parser_data_type &)> Callback =
1499	[](const typename ParserClass::parser_data_type &) {};
1500	};
1501
1502	extern template class opt<unsigned>;
1503	extern template class opt<int>;
1504	extern template class opt<std::string>;
1505	extern template class opt<char>;
1506	extern template class opt<bool>;
1507
1508	//===----------------------------------------------------------------------===//
1509	// Default storage class definition: external storage. This implementation
1510	// assumes the user will specify a variable to store the data into with the
1511	// cl::location(x) modifier.
1512	//
1513	template <class DataType, class StorageClass> class list_storage {
1514	StorageClass *Location = nullptr; // Where to store the object...
1515	std::vector<OptionValue<DataType>> Default =
1516	std::vector<OptionValue<DataType>>();
1517	bool DefaultAssigned = false;
1518
1519	public:
1520	list_storage() = default;
1521
1522	void clear() {}
1523
1524	bool setLocation(Option &O, StorageClass &L) {
1525	if (Location)
1526	return O.error(Message: "cl::location(x) specified more than once!");
1527	Location = &L;
1528	return false;
1529	}
1530
1531	template <class T> void addValue(const T &V, bool initial = false) {
1532	assert(Location != nullptr &&
1533	"cl::location(...) not specified for a command "
1534	"line option with external storage!");
1535	Location->push_back(V);
1536	if (initial)
1537	Default.push_back(V);
1538	}
1539
1540	const std::vector<OptionValue<DataType>> &getDefault() const {
1541	return Default;
1542	}
1543
1544	void assignDefault() { DefaultAssigned = true; }
1545	void overwriteDefault() { DefaultAssigned = false; }
1546	bool isDefaultAssigned() { return DefaultAssigned; }
1547	};
1548
1549	// Define how to hold a class type object, such as a string.
1550	// Originally this code inherited from std::vector. In transitioning to a new
1551	// API for command line options we should change this. The new implementation
1552	// of this list_storage specialization implements the minimum subset of the
1553	// std::vector API required for all the current clients.
1554	//
1555	// FIXME: Reduce this API to a more narrow subset of std::vector
1556	//
1557	template <class DataType> class list_storage<DataType, bool> {
1558	std::vector<DataType> Storage;
1559	std::vector<OptionValue<DataType>> Default;
1560	bool DefaultAssigned = false;
1561
1562	public:
1563	using iterator = typename std::vector<DataType>::iterator;
1564
1565	iterator begin() { return Storage.begin(); }
1566	iterator end() { return Storage.end(); }
1567
1568	using const_iterator = typename std::vector<DataType>::const_iterator;
1569
1570	const_iterator begin() const { return Storage.begin(); }
1571	const_iterator end() const { return Storage.end(); }
1572
1573	using size_type = typename std::vector<DataType>::size_type;
1574
1575	size_type size() const { return Storage.size(); }
1576
1577	bool empty() const { return Storage.empty(); }
1578
1579	void push_back(const DataType &value) { Storage.push_back(value); }
1580	void push_back(DataType &&value) { Storage.push_back(value); }
1581
1582	using reference = typename std::vector<DataType>::reference;
1583	using const_reference = typename std::vector<DataType>::const_reference;
1584
1585	reference operator[](size_type pos) { return Storage[pos]; }
1586	const_reference operator[](size_type pos) const { return Storage[pos]; }
1587
1588	void clear() {
1589	Storage.clear();
1590	}
1591
1592	iterator erase(const_iterator pos) { return Storage.erase(pos); }
1593	iterator erase(const_iterator first, const_iterator last) {
1594	return Storage.erase(first, last);
1595	}
1596
1597	iterator erase(iterator pos) { return Storage.erase(pos); }
1598	iterator erase(iterator first, iterator last) {
1599	return Storage.erase(first, last);
1600	}
1601
1602	iterator insert(const_iterator pos, const DataType &value) {
1603	return Storage.insert(pos, value);
1604	}
1605	iterator insert(const_iterator pos, DataType &&value) {
1606	return Storage.insert(pos, value);
1607	}
1608
1609	iterator insert(iterator pos, const DataType &value) {
1610	return Storage.insert(pos, value);
1611	}
1612	iterator insert(iterator pos, DataType &&value) {
1613	return Storage.insert(pos, value);
1614	}
1615
1616	reference front() { return Storage.front(); }
1617	const_reference front() const { return Storage.front(); }
1618
1619	operator std::vector<DataType> &() { return Storage; }
1620	operator ArrayRef<DataType>() const { return Storage; }
1621	std::vector<DataType> *operator&() { return &Storage; }
1622	const std::vector<DataType> *operator&() const { return &Storage; }
1623
1624	template <class T> void addValue(const T &V, bool initial = false) {
1625	Storage.push_back(V);
1626	if (initial)
1627	Default.push_back(OptionValue<DataType>(V));
1628	}
1629
1630	const std::vector<OptionValue<DataType>> &getDefault() const {
1631	return Default;
1632	}
1633
1634	void assignDefault() { DefaultAssigned = true; }
1635	void overwriteDefault() { DefaultAssigned = false; }
1636	bool isDefaultAssigned() { return DefaultAssigned; }
1637	};
1638
1639	//===----------------------------------------------------------------------===//
1640	// A list of command line options.
1641	//
1642	template <class DataType, class StorageClass = bool,
1643	class ParserClass = parser<DataType>>
1644	class list : public Option, public list_storage<DataType, StorageClass> {
1645	std::vector<unsigned> Positions;
1646	ParserClass Parser;
1647
1648	enum ValueExpected getValueExpectedFlagDefault() const override {
1649	return Parser.getValueExpectedFlagDefault();
1650	}
1651
1652	void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1653	return Parser.getExtraOptionNames(OptionNames);
1654	}
1655
1656	bool handleOccurrence(unsigned pos, StringRef ArgName,
1657	StringRef Arg) override {
1658	typename ParserClass::parser_data_type Val =
1659	typename ParserClass::parser_data_type();
1660	if (list_storage<DataType, StorageClass>::isDefaultAssigned()) {
1661	clear();
1662	list_storage<DataType, StorageClass>::overwriteDefault();
1663	}
1664	if (Parser.parse(*this, ArgName, Arg, Val))
1665	return true; // Parse Error!
1666	list_storage<DataType, StorageClass>::addValue(Val);
1667	setPosition(pos);
1668	Positions.push_back(x: pos);
1669	Callback(Val);
1670	return false;
1671	}
1672
1673	// Forward printing stuff to the parser...
1674	size_t getOptionWidth() const override {
1675	return Parser.getOptionWidth(*this);
1676	}
1677
1678	void printOptionInfo(size_t GlobalWidth) const override {
1679	Parser.printOptionInfo(*this, GlobalWidth);
1680	}
1681
1682	// Unimplemented: list options don't currently store their default value.
1683	void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1684	}
1685
1686	void setDefault() override {
1687	Positions.clear();
1688	list_storage<DataType, StorageClass>::clear();
1689	for (auto &Val : list_storage<DataType, StorageClass>::getDefault())
1690	list_storage<DataType, StorageClass>::addValue(Val.getValue());
1691	}
1692
1693	void done() {
1694	addArgument();
1695	Parser.initialize();
1696	}
1697
1698	public:
1699	// Command line options should not be copyable
1700	list(const list &) = delete;
1701	list &operator=(const list &) = delete;
1702
1703	ParserClass &getParser() { return Parser; }
1704
1705	unsigned getPosition(unsigned optnum) const {
1706	assert(optnum < this->size() && "Invalid option index");
1707	return Positions[optnum];
1708	}
1709
1710	void clear() {
1711	Positions.clear();
1712	list_storage<DataType, StorageClass>::clear();
1713	}
1714
1715	// setInitialValues - Used by the cl::list_init modifier...
1716	void setInitialValues(ArrayRef<DataType> Vs) {
1717	assert(!(list_storage<DataType, StorageClass>::isDefaultAssigned()) &&
1718	"Cannot have two default values");
1719	list_storage<DataType, StorageClass>::assignDefault();
1720	for (auto &Val : Vs)
1721	list_storage<DataType, StorageClass>::addValue(Val, true);
1722	}
1723
1724	void setNumAdditionalVals(unsigned n) { Option::setNumAdditionalVals(n); }
1725
1726	template <class... Mods>
1727	explicit list(const Mods &... Ms)
1728	: Option(ZeroOrMore, NotHidden), Parser(*this) {
1729	apply(this, Ms...);
1730	done();
1731	}
1732
1733	void setCallback(
1734	std::function<void(const typename ParserClass::parser_data_type &)> CB) {
1735	Callback = CB;
1736	}
1737
1738	std::function<void(const typename ParserClass::parser_data_type &)> Callback =
1739	[](const typename ParserClass::parser_data_type &) {};
1740	};
1741
1742	// Modifier to set the number of additional values.
1743	struct multi_val {
1744	unsigned AdditionalVals;
1745	explicit multi_val(unsigned N) : AdditionalVals(N) {}
1746
1747	template <typename D, typename S, typename P>
1748	void apply(list<D, S, P> &L) const {
1749	L.setNumAdditionalVals(AdditionalVals);
1750	}
1751	};
1752
1753	//===----------------------------------------------------------------------===//
1754	// Default storage class definition: external storage. This implementation
1755	// assumes the user will specify a variable to store the data into with the
1756	// cl::location(x) modifier.
1757	//
1758	template <class DataType, class StorageClass> class bits_storage {
1759	unsigned *Location = nullptr; // Where to store the bits...
1760
1761	template <class T> static unsigned Bit(const T &V) {
1762	unsigned BitPos = static_cast<unsigned>(V);
1763	assert(BitPos < sizeof(unsigned) * CHAR_BIT &&
1764	"enum exceeds width of bit vector!");
1765	return 1 << BitPos;
1766	}
1767
1768	public:
1769	bits_storage() = default;
1770
1771	bool setLocation(Option &O, unsigned &L) {
1772	if (Location)
1773	return O.error(Message: "cl::location(x) specified more than once!");
1774	Location = &L;
1775	return false;
1776	}
1777
1778	template <class T> void addValue(const T &V) {
1779	assert(Location != nullptr &&
1780	"cl::location(...) not specified for a command "
1781	"line option with external storage!");
1782	*Location |= Bit(V);
1783	}
1784
1785	unsigned getBits() { return *Location; }
1786
1787	void clear() {
1788	if (Location)
1789	*Location = 0;
1790	}
1791
1792	template <class T> bool isSet(const T &V) {
1793	return (*Location & Bit(V)) != 0;
1794	}
1795	};
1796
1797	// Define how to hold bits. Since we can inherit from a class, we do so.
1798	// This makes us exactly compatible with the bits in all cases that it is used.
1799	//
1800	template <class DataType> class bits_storage<DataType, bool> {
1801	unsigned Bits{0}; // Where to store the bits...
1802
1803	template <class T> static unsigned Bit(const T &V) {
1804	unsigned BitPos = static_cast<unsigned>(V);
1805	assert(BitPos < sizeof(unsigned) * CHAR_BIT &&
1806	"enum exceeds width of bit vector!");
1807	return 1 << BitPos;
1808	}
1809
1810	public:
1811	template <class T> void addValue(const T &V) { Bits |= Bit(V); }
1812
1813	unsigned getBits() { return Bits; }
1814
1815	void clear() { Bits = 0; }
1816
1817	template <class T> bool isSet(const T &V) { return (Bits & Bit(V)) != 0; }
1818	};
1819
1820	//===----------------------------------------------------------------------===//
1821	// A bit vector of command options.
1822	//
1823	template <class DataType, class Storage = bool,
1824	class ParserClass = parser<DataType>>
1825	class bits : public Option, public bits_storage<DataType, Storage> {
1826	std::vector<unsigned> Positions;
1827	ParserClass Parser;
1828
1829	enum ValueExpected getValueExpectedFlagDefault() const override {
1830	return Parser.getValueExpectedFlagDefault();
1831	}
1832
1833	void getExtraOptionNames(SmallVectorImpl<StringRef> &OptionNames) override {
1834	return Parser.getExtraOptionNames(OptionNames);
1835	}
1836
1837	bool handleOccurrence(unsigned pos, StringRef ArgName,
1838	StringRef Arg) override {
1839	typename ParserClass::parser_data_type Val =
1840	typename ParserClass::parser_data_type();
1841	if (Parser.parse(*this, ArgName, Arg, Val))
1842	return true; // Parse Error!
1843	this->addValue(Val);
1844	setPosition(pos);
1845	Positions.push_back(x: pos);
1846	Callback(Val);
1847	return false;
1848	}
1849
1850	// Forward printing stuff to the parser...
1851	size_t getOptionWidth() const override {
1852	return Parser.getOptionWidth(*this);
1853	}
1854
1855	void printOptionInfo(size_t GlobalWidth) const override {
1856	Parser.printOptionInfo(*this, GlobalWidth);
1857	}
1858
1859	// Unimplemented: bits options don't currently store their default values.
1860	void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1861	}
1862
1863	void setDefault() override { bits_storage<DataType, Storage>::clear(); }
1864
1865	void done() {
1866	addArgument();
1867	Parser.initialize();
1868	}
1869
1870	public:
1871	// Command line options should not be copyable
1872	bits(const bits &) = delete;
1873	bits &operator=(const bits &) = delete;
1874
1875	ParserClass &getParser() { return Parser; }
1876
1877	unsigned getPosition(unsigned optnum) const {
1878	assert(optnum < this->size() && "Invalid option index");
1879	return Positions[optnum];
1880	}
1881
1882	template <class... Mods>
1883	explicit bits(const Mods &... Ms)
1884	: Option(ZeroOrMore, NotHidden), Parser(*this) {
1885	apply(this, Ms...);
1886	done();
1887	}
1888
1889	void setCallback(
1890	std::function<void(const typename ParserClass::parser_data_type &)> CB) {
1891	Callback = CB;
1892	}
1893
1894	std::function<void(const typename ParserClass::parser_data_type &)> Callback =
1895	[](const typename ParserClass::parser_data_type &) {};
1896	};
1897
1898	//===----------------------------------------------------------------------===//
1899	// Aliased command line option (alias this name to a preexisting name)
1900	//
1901
1902	class alias : public Option {
1903	Option *AliasFor;
1904
1905	bool handleOccurrence(unsigned pos, StringRef /*ArgName*/,
1906	StringRef Arg) override {
1907	return AliasFor->handleOccurrence(pos, ArgName: AliasFor->ArgStr, Arg);
1908	}
1909
1910	bool addOccurrence(unsigned pos, StringRef /*ArgName*/, StringRef Value,
1911	bool MultiArg = false) override {
1912	return AliasFor->addOccurrence(pos, ArgName: AliasFor->ArgStr, Value, MultiArg);
1913	}
1914
1915	// Handle printing stuff...
1916	size_t getOptionWidth() const override;
1917	void printOptionInfo(size_t GlobalWidth) const override;
1918
1919	// Aliases do not need to print their values.
1920	void printOptionValue(size_t /*GlobalWidth*/, bool /*Force*/) const override {
1921	}
1922
1923	void setDefault() override { AliasFor->setDefault(); }
1924
1925	ValueExpected getValueExpectedFlagDefault() const override {
1926	return AliasFor->getValueExpectedFlag();
1927	}
1928
1929	void done() {
1930	if (!hasArgStr())
1931	error(Message: "cl::alias must have argument name specified!");
1932	if (!AliasFor)
1933	error(Message: "cl::alias must have an cl::aliasopt(option) specified!");
1934	if (!Subs.empty())
1935	error(Message: "cl::alias must not have cl::sub(), aliased option's cl::sub() will be used!");
1936	Subs = AliasFor->Subs;
1937	Categories = AliasFor->Categories;
1938	addArgument();
1939	}
1940
1941	public:
1942	// Command line options should not be copyable
1943	alias(const alias &) = delete;
1944	alias &operator=(const alias &) = delete;
1945
1946	void setAliasFor(Option &O) {
1947	if (AliasFor)
1948	error(Message: "cl::alias must only have one cl::aliasopt(...) specified!");
1949	AliasFor = &O;
1950	}
1951
1952	template <class... Mods>
1953	explicit alias(const Mods &... Ms)
1954	: Option(Optional, Hidden), AliasFor(nullptr) {
1955	apply(this, Ms...);
1956	done();
1957	}
1958	};
1959
1960	// Modifier to set the option an alias aliases.
1961	struct aliasopt {
1962	Option &Opt;
1963
1964	explicit aliasopt(Option &O) : Opt(O) {}
1965
1966	void apply(alias &A) const { A.setAliasFor(Opt); }
1967	};
1968
1969	// Provide additional help at the end of the normal help output. All occurrences
1970	// of cl::extrahelp will be accumulated and printed to stderr at the end of the
1971	// regular help, just before exit is called.
1972	struct extrahelp {
1973	StringRef morehelp;
1974
1975	explicit extrahelp(StringRef help);
1976	};
1977
1978	void PrintVersionMessage();
1979
1980	/// This function just prints the help message, exactly the same way as if the
1981	/// -help or -help-hidden option had been given on the command line.
1982	///
1983	/// \param Hidden if true will print hidden options
1984	/// \param Categorized if true print options in categories
1985	void PrintHelpMessage(bool Hidden = false, bool Categorized = false);
1986
1987	//===----------------------------------------------------------------------===//
1988	// Public interface for accessing registered options.
1989	//
1990
1991	/// Use this to get a StringMap to all registered named options
1992	/// (e.g. -help).
1993	///
1994	/// \return A reference to the StringMap used by the cl APIs to parse options.
1995	///
1996	/// Access to unnamed arguments (i.e. positional) are not provided because
1997	/// it is expected that the client already has access to these.
1998	///
1999	/// Typical usage:
2000	/// \code
2001	/// main(int argc,char* argv[]) {
2002	/// StringMap<llvm::cl::Option*> &opts = llvm::cl::getRegisteredOptions();
2003	/// assert(opts.count("help") == 1)
2004	/// opts["help"]->setDescription("Show alphabetical help information")
2005	/// // More code
2006	/// llvm::cl::ParseCommandLineOptions(argc,argv);
2007	/// //More code
2008	/// }
2009	/// \endcode
2010	///
2011	/// This interface is useful for modifying options in libraries that are out of
2012	/// the control of the client. The options should be modified before calling
2013	/// llvm::cl::ParseCommandLineOptions().
2014	///
2015	/// Hopefully this API can be deprecated soon. Any situation where options need
2016	/// to be modified by tools or libraries should be handled by sane APIs rather
2017	/// than just handing around a global list.
2018	StringMap<Option *> &
2019	getRegisteredOptions(SubCommand &Sub = SubCommand::getTopLevel());
2020
2021	/// Use this to get all registered SubCommands from the provided parser.
2022	///
2023	/// \return A range of all SubCommand pointers registered with the parser.
2024	///
2025	/// Typical usage:
2026	/// \code
2027	/// main(int argc, char* argv[]) {
2028	/// llvm::cl::ParseCommandLineOptions(argc, argv);
2029	/// for (auto* S : llvm::cl::getRegisteredSubcommands()) {
2030	/// if (*S) {
2031	/// std::cout << "Executing subcommand: " << S->getName() << std::endl;
2032	/// // Execute some function based on the name...
2033	/// }
2034	/// }
2035	/// }
2036	/// \endcode
2037	///
2038	/// This interface is useful for defining subcommands in libraries and
2039	/// the dispatch from a single point (like in the main function).
2040	iterator_range<typename SmallPtrSet<SubCommand *, 4>::iterator>
2041	getRegisteredSubcommands();
2042
2043	//===----------------------------------------------------------------------===//
2044	// Standalone command line processing utilities.
2045	//
2046
2047	/// Tokenizes a command line that can contain escapes and quotes.
2048	//
2049	/// The quoting rules match those used by GCC and other tools that use
2050	/// libiberty's buildargv() or expandargv() utilities, and do not match bash.
2051	/// They differ from buildargv() on treatment of backslashes that do not escape
2052	/// a special character to make it possible to accept most Windows file paths.
2053	///
2054	/// \param [in] Source The string to be split on whitespace with quotes.
2055	/// \param [in] Saver Delegates back to the caller for saving parsed strings.
2056	/// \param [in] MarkEOLs true if tokenizing a response file and you want end of
2057	/// lines and end of the response file to be marked with a nullptr string.
2058	/// \param [out] NewArgv All parsed strings are appended to NewArgv.
2059	void TokenizeGNUCommandLine(StringRef Source, StringSaver &Saver,
2060	SmallVectorImpl<const char *> &NewArgv,
2061	bool MarkEOLs = false);
2062
2063	/// Tokenizes a string of Windows command line arguments, which may contain
2064	/// quotes and escaped quotes.
2065	///
2066	/// See MSDN docs for CommandLineToArgvW for information on the quoting rules.
2067	/// http://msdn.microsoft.com/en-us/library/windows/desktop/17w5ykft(v=vs.85).aspx
2068	///
2069	/// For handling a full Windows command line including the executable name at
2070	/// the start, see TokenizeWindowsCommandLineFull below.
2071	///
2072	/// \param [in] Source The string to be split on whitespace with quotes.
2073	/// \param [in] Saver Delegates back to the caller for saving parsed strings.
2074	/// \param [in] MarkEOLs true if tokenizing a response file and you want end of
2075	/// lines and end of the response file to be marked with a nullptr string.
2076	/// \param [out] NewArgv All parsed strings are appended to NewArgv.
2077	void TokenizeWindowsCommandLine(StringRef Source, StringSaver &Saver,
2078	SmallVectorImpl<const char *> &NewArgv,
2079	bool MarkEOLs = false);
2080
2081	/// Tokenizes a Windows command line while attempting to avoid copies. If no
2082	/// quoting or escaping was used, this produces substrings of the original
2083	/// string. If a token requires unquoting, it will be allocated with the
2084	/// StringSaver.
2085	void TokenizeWindowsCommandLineNoCopy(StringRef Source, StringSaver &Saver,
2086	SmallVectorImpl<StringRef> &NewArgv);
2087
2088	/// Tokenizes a Windows full command line, including command name at the start.
2089	///
2090	/// This uses the same syntax rules as TokenizeWindowsCommandLine for all but
2091	/// the first token. But the first token is expected to be parsed as the
2092	/// executable file name in the way CreateProcess would do it, rather than the
2093	/// way the C library startup code would do it: CreateProcess does not consider
2094	/// that \ is ever an escape character (because " is not a valid filename char,
2095	/// hence there's never a need to escape it to be used literally).
2096	///
2097	/// Parameters are the same as for TokenizeWindowsCommandLine. In particular,
2098	/// if you set MarkEOLs = true, then the first word of every line will be
2099	/// parsed using the special rules for command names, making this function
2100	/// suitable for parsing a file full of commands to execute.
2101	void TokenizeWindowsCommandLineFull(StringRef Source, StringSaver &Saver,
2102	SmallVectorImpl<const char *> &NewArgv,
2103	bool MarkEOLs = false);
2104
2105	/// String tokenization function type. Should be compatible with either
2106	/// Windows or Unix command line tokenizers.
2107	using TokenizerCallback = void (*)(StringRef Source, StringSaver &Saver,
2108	SmallVectorImpl<const char *> &NewArgv,
2109	bool MarkEOLs);
2110
2111	/// Tokenizes content of configuration file.
2112	///
2113	/// \param [in] Source The string representing content of config file.
2114	/// \param [in] Saver Delegates back to the caller for saving parsed strings.
2115	/// \param [out] NewArgv All parsed strings are appended to NewArgv.
2116	/// \param [in] MarkEOLs Added for compatibility with TokenizerCallback.
2117	///
2118	/// It works like TokenizeGNUCommandLine with ability to skip comment lines.
2119	///
2120	void tokenizeConfigFile(StringRef Source, StringSaver &Saver,
2121	SmallVectorImpl<const char *> &NewArgv,
2122	bool MarkEOLs = false);
2123
2124	/// Contains options that control response file expansion.
2125	class ExpansionContext {
2126	/// Provides persistent storage for parsed strings.
2127	StringSaver Saver;
2128
2129	/// Tokenization strategy. Typically Unix or Windows.
2130	TokenizerCallback Tokenizer;
2131
2132	/// File system used for all file access when running the expansion.
2133	vfs::FileSystem *FS;
2134
2135	/// Path used to resolve relative rsp files. If empty, the file system
2136	/// current directory is used instead.
2137	StringRef CurrentDir;
2138
2139	/// Directories used for search of config files.
2140	ArrayRef<StringRef> SearchDirs;
2141
2142	/// True if names of nested response files must be resolved relative to
2143	/// including file.
2144	bool RelativeNames = false;
2145
2146	/// If true, mark end of lines and the end of the response file with nullptrs
2147	/// in the Argv vector.
2148	bool MarkEOLs = false;
2149
2150	/// If true, body of config file is expanded.
2151	bool InConfigFile = false;
2152
2153	llvm::Error expandResponseFile(StringRef FName,
2154	SmallVectorImpl<const char *> &NewArgv);
2155
2156	public:
2157	ExpansionContext(BumpPtrAllocator &A, TokenizerCallback T);
2158
2159	ExpansionContext &setMarkEOLs(bool X) {
2160	MarkEOLs = X;
2161	return *this;
2162	}
2163
2164	ExpansionContext &setRelativeNames(bool X) {
2165	RelativeNames = X;
2166	return *this;
2167	}
2168
2169	ExpansionContext &setCurrentDir(StringRef X) {
2170	CurrentDir = X;
2171	return *this;
2172	}
2173
2174	ExpansionContext &setSearchDirs(ArrayRef<StringRef> X) {
2175	SearchDirs = X;
2176	return *this;
2177	}
2178
2179	ExpansionContext &setVFS(vfs::FileSystem *X) {
2180	FS = X;
2181	return *this;
2182	}
2183
2184	/// Looks for the specified configuration file.
2185	///
2186	/// \param[in] FileName Name of the file to search for.
2187	/// \param[out] FilePath File absolute path, if it was found.
2188	/// \return True if file was found.
2189	///
2190	/// If the specified file name contains a directory separator, it is searched
2191	/// for by its absolute path. Otherwise looks for file sequentially in
2192	/// directories specified by SearchDirs field.
2193	bool findConfigFile(StringRef FileName, SmallVectorImpl<char> &FilePath);
2194
2195	/// Reads command line options from the given configuration file.
2196	///
2197	/// \param [in] CfgFile Path to configuration file.
2198	/// \param [out] Argv Array to which the read options are added.
2199	/// \return true if the file was successfully read.
2200	///
2201	/// It reads content of the specified file, tokenizes it and expands "@file"
2202	/// commands resolving file names in them relative to the directory where
2203	/// CfgFilename resides. It also expands "<CFGDIR>" to the base path of the
2204	/// current config file.
2205	Error readConfigFile(StringRef CfgFile, SmallVectorImpl<const char *> &Argv);
2206
2207	/// Expands constructs "@file" in the provided array of arguments recursively.
2208	Error expandResponseFiles(SmallVectorImpl<const char *> &Argv);
2209	};
2210
2211	/// A convenience helper which concatenates the options specified by the
2212	/// environment variable EnvVar and command line options, then expands
2213	/// response files recursively.
2214	/// \return true if all @files were expanded successfully or there were none.
2215	bool expandResponseFiles(int Argc, const char *const *Argv, const char *EnvVar,
2216	SmallVectorImpl<const char *> &NewArgv);
2217
2218	/// A convenience helper which supports the typical use case of expansion
2219	/// function call.
2220	bool ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
2221	SmallVectorImpl<const char *> &Argv);
2222
2223	/// A convenience helper which concatenates the options specified by the
2224	/// environment variable EnvVar and command line options, then expands response
2225	/// files recursively. The tokenizer is a predefined GNU or Windows one.
2226	/// \return true if all @files were expanded successfully or there were none.
2227	bool expandResponseFiles(int Argc, const char *const *Argv, const char *EnvVar,
2228	StringSaver &Saver,
2229	SmallVectorImpl<const char *> &NewArgv);
2230
2231	/// Mark all options not part of this category as cl::ReallyHidden.
2232	///
2233	/// \param Category the category of options to keep displaying
2234	///
2235	/// Some tools (like clang-format) like to be able to hide all options that are
2236	/// not specific to the tool. This function allows a tool to specify a single
2237	/// option category to display in the -help output.
2238	void HideUnrelatedOptions(cl::OptionCategory &Category,
2239	SubCommand &Sub = SubCommand::getTopLevel());
2240
2241	/// Mark all options not part of the categories as cl::ReallyHidden.
2242	///
2243	/// \param Categories the categories of options to keep displaying.
2244	///
2245	/// Some tools (like clang-format) like to be able to hide all options that are
2246	/// not specific to the tool. This function allows a tool to specify a single
2247	/// option category to display in the -help output.
2248	void HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories,
2249	SubCommand &Sub = SubCommand::getTopLevel());
2250
2251	/// Reset all command line options to a state that looks as if they have
2252	/// never appeared on the command line. This is useful for being able to parse
2253	/// a command line multiple times (especially useful for writing tests).
2254	void ResetAllOptionOccurrences();
2255
2256	/// Reset the command line parser back to its initial state. This
2257	/// removes
2258	/// all options, categories, and subcommands and returns the parser to a state
2259	/// where no options are supported.
2260	void ResetCommandLineParser();
2261
2262	/// Parses `Arg` into the option handler `Handler`.
2263	bool ProvidePositionalOption(Option *Handler, StringRef Arg, int i);
2264
2265	} // end namespace cl
2266
2267	} // end namespace llvm
2268
2269	#endif // LLVM_SUPPORT_COMMANDLINE_H
2270