1	//===- Type.h - C Language Family Type Representation -----------*- 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	/// \file
10	/// C Language Family Type Representation
11	///
12	/// This file defines the clang::Type interface and subclasses, used to
13	/// represent types for languages in the C family.
14	//
15	//===----------------------------------------------------------------------===//
16
17	#ifndef LLVM_CLANG_AST_TYPE_H
18	#define LLVM_CLANG_AST_TYPE_H
19
20	#include "clang/AST/DependenceFlags.h"
21	#include "clang/AST/NestedNameSpecifier.h"
22	#include "clang/AST/TemplateName.h"
23	#include "clang/Basic/AddressSpaces.h"
24	#include "clang/Basic/AttrKinds.h"
25	#include "clang/Basic/Diagnostic.h"
26	#include "clang/Basic/ExceptionSpecificationType.h"
27	#include "clang/Basic/LLVM.h"
28	#include "clang/Basic/Linkage.h"
29	#include "clang/Basic/PartialDiagnostic.h"
30	#include "clang/Basic/SourceLocation.h"
31	#include "clang/Basic/Specifiers.h"
32	#include "clang/Basic/Visibility.h"
33	#include "llvm/ADT/APInt.h"
34	#include "llvm/ADT/APSInt.h"
35	#include "llvm/ADT/ArrayRef.h"
36	#include "llvm/ADT/FoldingSet.h"
37	#include "llvm/ADT/PointerIntPair.h"
38	#include "llvm/ADT/PointerUnion.h"
39	#include "llvm/ADT/STLForwardCompat.h"
40	#include "llvm/ADT/StringRef.h"
41	#include "llvm/ADT/Twine.h"
42	#include "llvm/ADT/iterator_range.h"
43	#include "llvm/Support/Casting.h"
44	#include "llvm/Support/Compiler.h"
45	#include "llvm/Support/ErrorHandling.h"
46	#include "llvm/Support/PointerLikeTypeTraits.h"
47	#include "llvm/Support/TrailingObjects.h"
48	#include "llvm/Support/type_traits.h"
49	#include <cassert>
50	#include <cstddef>
51	#include <cstdint>
52	#include <cstring>
53	#include <optional>
54	#include <string>
55	#include <type_traits>
56	#include <utility>
57
58	namespace clang {
59
60	class BTFTypeTagAttr;
61	class ExtQuals;
62	class QualType;
63	class ConceptDecl;
64	class ValueDecl;
65	class TagDecl;
66	class TemplateParameterList;
67	class Type;
68
69	enum {
70	TypeAlignmentInBits = 4,
71	TypeAlignment = 1 << TypeAlignmentInBits
72	};
73
74	namespace serialization {
75	template <class T> class AbstractTypeReader;
76	template <class T> class AbstractTypeWriter;
77	}
78
79	} // namespace clang
80
81	namespace llvm {
82
83	template <typename T>
84	struct PointerLikeTypeTraits;
85	template<>
86	struct PointerLikeTypeTraits< ::clang::Type*> {
87	static inline void *getAsVoidPointer(::clang::Type *P) { return P; }
88
89	static inline ::clang::Type *getFromVoidPointer(void *P) {
90	return static_cast< ::clang::Type*>(P);
91	}
92
93	static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
94	};
95
96	template<>
97	struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
98	static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }
99
100	static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
101	return static_cast< ::clang::ExtQuals*>(P);
102	}
103
104	static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
105	};
106
107	} // namespace llvm
108
109	namespace clang {
110
111	class ASTContext;
112	template <typename> class CanQual;
113	class CXXRecordDecl;
114	class DeclContext;
115	class EnumDecl;
116	class Expr;
117	class ExtQualsTypeCommonBase;
118	class FunctionDecl;
119	class IdentifierInfo;
120	class NamedDecl;
121	class ObjCInterfaceDecl;
122	class ObjCProtocolDecl;
123	class ObjCTypeParamDecl;
124	struct PrintingPolicy;
125	class RecordDecl;
126	class Stmt;
127	class TagDecl;
128	class TemplateArgument;
129	class TemplateArgumentListInfo;
130	class TemplateArgumentLoc;
131	class TemplateTypeParmDecl;
132	class TypedefNameDecl;
133	class UnresolvedUsingTypenameDecl;
134	class UsingShadowDecl;
135
136	using CanQualType = CanQual<Type>;
137
138	// Provide forward declarations for all of the *Type classes.
139	#define TYPE(Class, Base) class Class##Type;
140	#include "clang/AST/TypeNodes.inc"
141
142	/// The collection of all-type qualifiers we support.
143	/// Clang supports five independent qualifiers:
144	/// * C99: const, volatile, and restrict
145	/// * MS: __unaligned
146	/// * Embedded C (TR18037): address spaces
147	/// * Objective C: the GC attributes (none, weak, or strong)
148	class Qualifiers {
149	public:
150	enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
151	Const = 0x1,
152	Restrict = 0x2,
153	Volatile = 0x4,
154	CVRMask = Const | Volatile | Restrict
155	};
156
157	enum GC {
158	GCNone = 0,
159	Weak,
160	Strong
161	};
162
163	enum ObjCLifetime {
164	/// There is no lifetime qualification on this type.
165	OCL_None,
166
167	/// This object can be modified without requiring retains or
168	/// releases.
169	OCL_ExplicitNone,
170
171	/// Assigning into this object requires the old value to be
172	/// released and the new value to be retained. The timing of the
173	/// release of the old value is inexact: it may be moved to
174	/// immediately after the last known point where the value is
175	/// live.
176	OCL_Strong,
177
178	/// Reading or writing from this object requires a barrier call.
179	OCL_Weak,
180
181	/// Assigning into this object requires a lifetime extension.
182	OCL_Autoreleasing
183	};
184
185	enum {
186	/// The maximum supported address space number.
187	/// 23 bits should be enough for anyone.
188	MaxAddressSpace = 0x7fffffu,
189
190	/// The width of the "fast" qualifier mask.
191	FastWidth = 3,
192
193	/// The fast qualifier mask.
194	FastMask = (1 << FastWidth) - 1
195	};
196
197	/// Returns the common set of qualifiers while removing them from
198	/// the given sets.
199	static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
200	// If both are only CVR-qualified, bit operations are sufficient.
201	if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
202	Qualifiers Q;
203	Q.Mask = L.Mask & R.Mask;
204	L.Mask &= ~Q.Mask;
205	R.Mask &= ~Q.Mask;
206	return Q;
207	}
208
209	Qualifiers Q;
210	unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
211	Q.addCVRQualifiers(mask: CommonCRV);
212	L.removeCVRQualifiers(mask: CommonCRV);
213	R.removeCVRQualifiers(mask: CommonCRV);
214
215	if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
216	Q.setObjCGCAttr(L.getObjCGCAttr());
217	L.removeObjCGCAttr();
218	R.removeObjCGCAttr();
219	}
220
221	if (L.getObjCLifetime() == R.getObjCLifetime()) {
222	Q.setObjCLifetime(L.getObjCLifetime());
223	L.removeObjCLifetime();
224	R.removeObjCLifetime();
225	}
226
227	if (L.getAddressSpace() == R.getAddressSpace()) {
228	Q.setAddressSpace(L.getAddressSpace());
229	L.removeAddressSpace();
230	R.removeAddressSpace();
231	}
232	return Q;
233	}
234
235	static Qualifiers fromFastMask(unsigned Mask) {
236	Qualifiers Qs;
237	Qs.addFastQualifiers(mask: Mask);
238	return Qs;
239	}
240
241	static Qualifiers fromCVRMask(unsigned CVR) {
242	Qualifiers Qs;
243	Qs.addCVRQualifiers(mask: CVR);
244	return Qs;
245	}
246
247	static Qualifiers fromCVRUMask(unsigned CVRU) {
248	Qualifiers Qs;
249	Qs.addCVRUQualifiers(mask: CVRU);
250	return Qs;
251	}
252
253	// Deserialize qualifiers from an opaque representation.
254	static Qualifiers fromOpaqueValue(unsigned opaque) {
255	Qualifiers Qs;
256	Qs.Mask = opaque;
257	return Qs;
258	}
259
260	// Serialize these qualifiers into an opaque representation.
261	unsigned getAsOpaqueValue() const {
262	return Mask;
263	}
264
265	bool hasConst() const { return Mask & Const; }
266	bool hasOnlyConst() const { return Mask == Const; }
267	void removeConst() { Mask &= ~Const; }
268	void addConst() { Mask |= Const; }
269	Qualifiers withConst() const {
270	Qualifiers Qs = *this;
271	Qs.addConst();
272	return Qs;
273	}
274
275	bool hasVolatile() const { return Mask & Volatile; }
276	bool hasOnlyVolatile() const { return Mask == Volatile; }
277	void removeVolatile() { Mask &= ~Volatile; }
278	void addVolatile() { Mask |= Volatile; }
279	Qualifiers withVolatile() const {
280	Qualifiers Qs = *this;
281	Qs.addVolatile();
282	return Qs;
283	}
284
285	bool hasRestrict() const { return Mask & Restrict; }
286	bool hasOnlyRestrict() const { return Mask == Restrict; }
287	void removeRestrict() { Mask &= ~Restrict; }
288	void addRestrict() { Mask |= Restrict; }
289	Qualifiers withRestrict() const {
290	Qualifiers Qs = *this;
291	Qs.addRestrict();
292	return Qs;
293	}
294
295	bool hasCVRQualifiers() const { return getCVRQualifiers(); }
296	unsigned getCVRQualifiers() const { return Mask & CVRMask; }
297	unsigned getCVRUQualifiers() const { return Mask & (CVRMask | UMask); }
298
299	void setCVRQualifiers(unsigned mask) {
300	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
301	Mask = (Mask & ~CVRMask) | mask;
302	}
303	void removeCVRQualifiers(unsigned mask) {
304	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
305	Mask &= ~mask;
306	}
307	void removeCVRQualifiers() {
308	removeCVRQualifiers(mask: CVRMask);
309	}
310	void addCVRQualifiers(unsigned mask) {
311	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
312	Mask |= mask;
313	}
314	void addCVRUQualifiers(unsigned mask) {
315	assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits");
316	Mask |= mask;
317	}
318
319	bool hasUnaligned() const { return Mask & UMask; }
320	void setUnaligned(bool flag) {
321	Mask = (Mask & ~UMask) | (flag ? UMask : 0);
322	}
323	void removeUnaligned() { Mask &= ~UMask; }
324	void addUnaligned() { Mask |= UMask; }
325
326	bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
327	GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
328	void setObjCGCAttr(GC type) {
329	Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
330	}
331	void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
332	void addObjCGCAttr(GC type) {
333	assert(type);
334	setObjCGCAttr(type);
335	}
336	Qualifiers withoutObjCGCAttr() const {
337	Qualifiers qs = *this;
338	qs.removeObjCGCAttr();
339	return qs;
340	}
341	Qualifiers withoutObjCLifetime() const {
342	Qualifiers qs = *this;
343	qs.removeObjCLifetime();
344	return qs;
345	}
346	Qualifiers withoutAddressSpace() const {
347	Qualifiers qs = *this;
348	qs.removeAddressSpace();
349	return qs;
350	}
351
352	bool hasObjCLifetime() const { return Mask & LifetimeMask; }
353	ObjCLifetime getObjCLifetime() const {
354	return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
355	}
356	void setObjCLifetime(ObjCLifetime type) {
357	Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
358	}
359	void removeObjCLifetime() { setObjCLifetime(OCL_None); }
360	void addObjCLifetime(ObjCLifetime type) {
361	assert(type);
362	assert(!hasObjCLifetime());
363	Mask |= (type << LifetimeShift);
364	}
365
366	/// True if the lifetime is neither None or ExplicitNone.
367	bool hasNonTrivialObjCLifetime() const {
368	ObjCLifetime lifetime = getObjCLifetime();
369	return (lifetime > OCL_ExplicitNone);
370	}
371
372	/// True if the lifetime is either strong or weak.
373	bool hasStrongOrWeakObjCLifetime() const {
374	ObjCLifetime lifetime = getObjCLifetime();
375	return (lifetime == OCL_Strong || lifetime == OCL_Weak);
376	}
377
378	bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
379	LangAS getAddressSpace() const {
380	return static_cast<LangAS>(Mask >> AddressSpaceShift);
381	}
382	bool hasTargetSpecificAddressSpace() const {
383	return isTargetAddressSpace(AS: getAddressSpace());
384	}
385	/// Get the address space attribute value to be printed by diagnostics.
386	unsigned getAddressSpaceAttributePrintValue() const {
387	auto Addr = getAddressSpace();
388	// This function is not supposed to be used with language specific
389	// address spaces. If that happens, the diagnostic message should consider
390	// printing the QualType instead of the address space value.
391	assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace());
392	if (Addr != LangAS::Default)
393	return toTargetAddressSpace(AS: Addr);
394	// TODO: The diagnostic messages where Addr may be 0 should be fixed
395	// since it cannot differentiate the situation where 0 denotes the default
396	// address space or user specified __attribute__((address_space(0))).
397	return 0;
398	}
399	void setAddressSpace(LangAS space) {
400	assert((unsigned)space <= MaxAddressSpace);
401	Mask = (Mask & ~AddressSpaceMask)
402	| (((uint32_t) space) << AddressSpaceShift);
403	}
404	void removeAddressSpace() { setAddressSpace(LangAS::Default); }
405	void addAddressSpace(LangAS space) {
406	assert(space != LangAS::Default);
407	setAddressSpace(space);
408	}
409
410	// Fast qualifiers are those that can be allocated directly
411	// on a QualType object.
412	bool hasFastQualifiers() const { return getFastQualifiers(); }
413	unsigned getFastQualifiers() const { return Mask & FastMask; }
414	void setFastQualifiers(unsigned mask) {
415	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
416	Mask = (Mask & ~FastMask) | mask;
417	}
418	void removeFastQualifiers(unsigned mask) {
419	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
420	Mask &= ~mask;
421	}
422	void removeFastQualifiers() {
423	removeFastQualifiers(mask: FastMask);
424	}
425	void addFastQualifiers(unsigned mask) {
426	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
427	Mask |= mask;
428	}
429
430	/// Return true if the set contains any qualifiers which require an ExtQuals
431	/// node to be allocated.
432	bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
433	Qualifiers getNonFastQualifiers() const {
434	Qualifiers Quals = *this;
435	Quals.setFastQualifiers(0);
436	return Quals;
437	}
438
439	/// Return true if the set contains any qualifiers.
440	bool hasQualifiers() const { return Mask; }
441	bool empty() const { return !Mask; }
442
443	/// Add the qualifiers from the given set to this set.
444	void addQualifiers(Qualifiers Q) {
445	// If the other set doesn't have any non-boolean qualifiers, just
446	// bit-or it in.
447	if (!(Q.Mask & ~CVRMask))
448	Mask |= Q.Mask;
449	else {
450	Mask |= (Q.Mask & CVRMask);
451	if (Q.hasAddressSpace())
452	addAddressSpace(space: Q.getAddressSpace());
453	if (Q.hasObjCGCAttr())
454	addObjCGCAttr(type: Q.getObjCGCAttr());
455	if (Q.hasObjCLifetime())
456	addObjCLifetime(type: Q.getObjCLifetime());
457	}
458	}
459
460	/// Remove the qualifiers from the given set from this set.
461	void removeQualifiers(Qualifiers Q) {
462	// If the other set doesn't have any non-boolean qualifiers, just
463	// bit-and the inverse in.
464	if (!(Q.Mask & ~CVRMask))
465	Mask &= ~Q.Mask;
466	else {
467	Mask &= ~(Q.Mask & CVRMask);
468	if (getObjCGCAttr() == Q.getObjCGCAttr())
469	removeObjCGCAttr();
470	if (getObjCLifetime() == Q.getObjCLifetime())
471	removeObjCLifetime();
472	if (getAddressSpace() == Q.getAddressSpace())
473	removeAddressSpace();
474	}
475	}
476
477	/// Add the qualifiers from the given set to this set, given that
478	/// they don't conflict.
479	void addConsistentQualifiers(Qualifiers qs) {
480	assert(getAddressSpace() == qs.getAddressSpace() ||
481	!hasAddressSpace() || !qs.hasAddressSpace());
482	assert(getObjCGCAttr() == qs.getObjCGCAttr() ||
483	!hasObjCGCAttr() || !qs.hasObjCGCAttr());
484	assert(getObjCLifetime() == qs.getObjCLifetime() ||
485	!hasObjCLifetime() || !qs.hasObjCLifetime());
486	Mask |= qs.Mask;
487	}
488
489	/// Returns true if address space A is equal to or a superset of B.
490	/// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
491	/// overlapping address spaces.
492	/// CL1.1 or CL1.2:
493	/// every address space is a superset of itself.
494	/// CL2.0 adds:
495	/// __generic is a superset of any address space except for __constant.
496	static bool isAddressSpaceSupersetOf(LangAS A, LangAS B) {
497	// Address spaces must match exactly.
498	return A == B ||
499	// Otherwise in OpenCLC v2.0 s6.5.5: every address space except
500	// for __constant can be used as __generic.
501	(A == LangAS::opencl_generic && B != LangAS::opencl_constant) ||
502	// We also define global_device and global_host address spaces,
503	// to distinguish global pointers allocated on host from pointers
504	// allocated on device, which are a subset of __global.
505	(A == LangAS::opencl_global && (B == LangAS::opencl_global_device ||
506	B == LangAS::opencl_global_host)) ||
507	(A == LangAS::sycl_global && (B == LangAS::sycl_global_device ||
508	B == LangAS::sycl_global_host)) ||
509	// Consider pointer size address spaces to be equivalent to default.
510	((isPtrSizeAddressSpace(AS: A) || A == LangAS::Default) &&
511	(isPtrSizeAddressSpace(AS: B) || B == LangAS::Default)) ||
512	// Default is a superset of SYCL address spaces.
513	(A == LangAS::Default &&
514	(B == LangAS::sycl_private || B == LangAS::sycl_local ||
515	B == LangAS::sycl_global || B == LangAS::sycl_global_device ||
516	B == LangAS::sycl_global_host)) ||
517	// In HIP device compilation, any cuda address space is allowed
518	// to implicitly cast into the default address space.
519	(A == LangAS::Default &&
520	(B == LangAS::cuda_constant || B == LangAS::cuda_device ||
521	B == LangAS::cuda_shared));
522	}
523
524	/// Returns true if the address space in these qualifiers is equal to or
525	/// a superset of the address space in the argument qualifiers.
526	bool isAddressSpaceSupersetOf(Qualifiers other) const {
527	return isAddressSpaceSupersetOf(A: getAddressSpace(), B: other.getAddressSpace());
528	}
529
530	/// Determines if these qualifiers compatibly include another set.
531	/// Generally this answers the question of whether an object with the other
532	/// qualifiers can be safely used as an object with these qualifiers.
533	bool compatiblyIncludes(Qualifiers other) const {
534	return isAddressSpaceSupersetOf(other) &&
535	// ObjC GC qualifiers can match, be added, or be removed, but can't
536	// be changed.
537	(getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
538	!other.hasObjCGCAttr()) &&
539	// ObjC lifetime qualifiers must match exactly.
540	getObjCLifetime() == other.getObjCLifetime() &&
541	// CVR qualifiers may subset.
542	(((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
543	// U qualifier may superset.
544	(!other.hasUnaligned() || hasUnaligned());
545	}
546
547	/// Determines if these qualifiers compatibly include another set of
548	/// qualifiers from the narrow perspective of Objective-C ARC lifetime.
549	///
550	/// One set of Objective-C lifetime qualifiers compatibly includes the other
551	/// if the lifetime qualifiers match, or if both are non-__weak and the
552	/// including set also contains the 'const' qualifier, or both are non-__weak
553	/// and one is None (which can only happen in non-ARC modes).
554	bool compatiblyIncludesObjCLifetime(Qualifiers other) const {
555	if (getObjCLifetime() == other.getObjCLifetime())
556	return true;
557
558	if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
559	return false;
560
561	if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
562	return true;
563
564	return hasConst();
565	}
566
567	/// Determine whether this set of qualifiers is a strict superset of
568	/// another set of qualifiers, not considering qualifier compatibility.
569	bool isStrictSupersetOf(Qualifiers Other) const;
570
571	bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
572	bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
573
574	explicit operator bool() const { return hasQualifiers(); }
575
576	Qualifiers &operator+=(Qualifiers R) {
577	addQualifiers(Q: R);
578	return *this;
579	}
580
581	// Union two qualifier sets. If an enumerated qualifier appears
582	// in both sets, use the one from the right.
583	friend Qualifiers operator+(Qualifiers L, Qualifiers R) {
584	L += R;
585	return L;
586	}
587
588	Qualifiers &operator-=(Qualifiers R) {
589	removeQualifiers(Q: R);
590	return *this;
591	}
592
593	/// Compute the difference between two qualifier sets.
594	friend Qualifiers operator-(Qualifiers L, Qualifiers R) {
595	L -= R;
596	return L;
597	}
598
599	std::string getAsString() const;
600	std::string getAsString(const PrintingPolicy &Policy) const;
601
602	static std::string getAddrSpaceAsString(LangAS AS);
603
604	bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
605	void print(raw_ostream &OS, const PrintingPolicy &Policy,
606	bool appendSpaceIfNonEmpty = false) const;
607
608	void Profile(llvm::FoldingSetNodeID &ID) const {
609	ID.AddInteger(I: Mask);
610	}
611
612	private:
613	// bits: |0 1 2|3|4 .. 5|6 .. 8|9 ... 31|
614	// |C R V|U|GCAttr|Lifetime|AddressSpace|
615	uint32_t Mask = 0;
616
617	static const uint32_t UMask = 0x8;
618	static const uint32_t UShift = 3;
619	static const uint32_t GCAttrMask = 0x30;
620	static const uint32_t GCAttrShift = 4;
621	static const uint32_t LifetimeMask = 0x1C0;
622	static const uint32_t LifetimeShift = 6;
623	static const uint32_t AddressSpaceMask =
624	~(CVRMask | UMask | GCAttrMask | LifetimeMask);
625	static const uint32_t AddressSpaceShift = 9;
626	};
627
628	class QualifiersAndAtomic {
629	Qualifiers Quals;
630	bool HasAtomic;
631
632	public:
633	QualifiersAndAtomic() : HasAtomic(false) {}
634	QualifiersAndAtomic(Qualifiers Quals, bool HasAtomic)
635	: Quals(Quals), HasAtomic(HasAtomic) {}
636
637	operator Qualifiers() const { return Quals; }
638
639	bool hasVolatile() const { return Quals.hasVolatile(); }
640	bool hasConst() const { return Quals.hasConst(); }
641	bool hasRestrict() const { return Quals.hasRestrict(); }
642	bool hasAtomic() const { return HasAtomic; }
643
644	void addVolatile() { Quals.addVolatile(); }
645	void addConst() { Quals.addConst(); }
646	void addRestrict() { Quals.addRestrict(); }
647	void addAtomic() { HasAtomic = true; }
648
649	void removeVolatile() { Quals.removeVolatile(); }
650	void removeConst() { Quals.removeConst(); }
651	void removeRestrict() { Quals.removeRestrict(); }
652	void removeAtomic() { HasAtomic = false; }
653
654	QualifiersAndAtomic withVolatile() {
655	return {Quals.withVolatile(), HasAtomic};
656	}
657	QualifiersAndAtomic withConst() { return {Quals.withConst(), HasAtomic}; }
658	QualifiersAndAtomic withRestrict() {
659	return {Quals.withRestrict(), HasAtomic};
660	}
661	QualifiersAndAtomic withAtomic() { return {Quals, true}; }
662
663	QualifiersAndAtomic &operator+=(Qualifiers RHS) {
664	Quals += RHS;
665	return *this;
666	}
667	};
668
669	/// A std::pair-like structure for storing a qualified type split
670	/// into its local qualifiers and its locally-unqualified type.
671	struct SplitQualType {
672	/// The locally-unqualified type.
673	const Type *Ty = nullptr;
674
675	/// The local qualifiers.
676	Qualifiers Quals;
677
678	SplitQualType() = default;
679	SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
680
681	SplitQualType getSingleStepDesugaredType() const; // end of this file
682
683	// Make std::tie work.
684	std::pair<const Type *,Qualifiers> asPair() const {
685	return std::pair<const Type *, Qualifiers>(Ty, Quals);
686	}
687
688	friend bool operator==(SplitQualType a, SplitQualType b) {
689	return a.Ty == b.Ty && a.Quals == b.Quals;
690	}
691	friend bool operator!=(SplitQualType a, SplitQualType b) {
692	return a.Ty != b.Ty || a.Quals != b.Quals;
693	}
694	};
695
696	/// The kind of type we are substituting Objective-C type arguments into.
697	///
698	/// The kind of substitution affects the replacement of type parameters when
699	/// no concrete type information is provided, e.g., when dealing with an
700	/// unspecialized type.
701	enum class ObjCSubstitutionContext {
702	/// An ordinary type.
703	Ordinary,
704
705	/// The result type of a method or function.
706	Result,
707
708	/// The parameter type of a method or function.
709	Parameter,
710
711	/// The type of a property.
712	Property,
713
714	/// The superclass of a type.
715	Superclass,
716	};
717
718	/// The kind of 'typeof' expression we're after.
719	enum class TypeOfKind : uint8_t {
720	Qualified,
721	Unqualified,
722	};
723
724	/// A (possibly-)qualified type.
725	///
726	/// For efficiency, we don't store CV-qualified types as nodes on their
727	/// own: instead each reference to a type stores the qualifiers. This
728	/// greatly reduces the number of nodes we need to allocate for types (for
729	/// example we only need one for 'int', 'const int', 'volatile int',
730	/// 'const volatile int', etc).
731	///
732	/// As an added efficiency bonus, instead of making this a pair, we
733	/// just store the two bits we care about in the low bits of the
734	/// pointer. To handle the packing/unpacking, we make QualType be a
735	/// simple wrapper class that acts like a smart pointer. A third bit
736	/// indicates whether there are extended qualifiers present, in which
737	/// case the pointer points to a special structure.
738	class QualType {
739	friend class QualifierCollector;
740
741	// Thankfully, these are efficiently composable.
742	llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
743	Qualifiers::FastWidth> Value;
744
745	const ExtQuals *getExtQualsUnsafe() const {
746	return Value.getPointer().get<const ExtQuals*>();
747	}
748
749	const Type *getTypePtrUnsafe() const {
750	return Value.getPointer().get<const Type*>();
751	}
752
753	const ExtQualsTypeCommonBase *getCommonPtr() const {
754	assert(!isNull() && "Cannot retrieve a NULL type pointer");
755	auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
756	CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
757	return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
758	}
759
760	public:
761	QualType() = default;
762	QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
763	QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
764
765	unsigned getLocalFastQualifiers() const { return Value.getInt(); }
766	void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
767
768	bool UseExcessPrecision(const ASTContext &Ctx);
769
770	/// Retrieves a pointer to the underlying (unqualified) type.
771	///
772	/// This function requires that the type not be NULL. If the type might be
773	/// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
774	const Type *getTypePtr() const;
775
776	const Type *getTypePtrOrNull() const;
777
778	/// Retrieves a pointer to the name of the base type.
779	const IdentifierInfo *getBaseTypeIdentifier() const;
780
781	/// Divides a QualType into its unqualified type and a set of local
782	/// qualifiers.
783	SplitQualType split() const;
784
785	void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
786
787	static QualType getFromOpaquePtr(const void *Ptr) {
788	QualType T;
789	T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
790	return T;
791	}
792
793	const Type &operator*() const {
794	return *getTypePtr();
795	}
796
797	const Type *operator->() const {
798	return getTypePtr();
799	}
800
801	bool isCanonical() const;
802	bool isCanonicalAsParam() const;
803
804	/// Return true if this QualType doesn't point to a type yet.
805	bool isNull() const {
806	return Value.getPointer().isNull();
807	}
808
809	// Determines if a type can form `T&`.
810	bool isReferenceable() const;
811
812	/// Determine whether this particular QualType instance has the
813	/// "const" qualifier set, without looking through typedefs that may have
814	/// added "const" at a different level.
815	bool isLocalConstQualified() const {
816	return (getLocalFastQualifiers() & Qualifiers::Const);
817	}
818
819	/// Determine whether this type is const-qualified.
820	bool isConstQualified() const;
821
822	enum class NonConstantStorageReason {
823	MutableField,
824	NonConstNonReferenceType,
825	NonTrivialCtor,
826	NonTrivialDtor,
827	};
828	/// Determine whether instances of this type can be placed in immutable
829	/// storage.
830	/// If ExcludeCtor is true, the duration when the object's constructor runs
831	/// will not be considered. The caller will need to verify that the object is
832	/// not written to during its construction. ExcludeDtor works similarly.
833	std::optional<NonConstantStorageReason>
834	isNonConstantStorage(const ASTContext &Ctx, bool ExcludeCtor,
835	bool ExcludeDtor);
836
837	bool isConstantStorage(const ASTContext &Ctx, bool ExcludeCtor,
838	bool ExcludeDtor) {
839	return !isNonConstantStorage(Ctx, ExcludeCtor, ExcludeDtor);
840	}
841
842	/// Determine whether this particular QualType instance has the
843	/// "restrict" qualifier set, without looking through typedefs that may have
844	/// added "restrict" at a different level.
845	bool isLocalRestrictQualified() const {
846	return (getLocalFastQualifiers() & Qualifiers::Restrict);
847	}
848
849	/// Determine whether this type is restrict-qualified.
850	bool isRestrictQualified() const;
851
852	/// Determine whether this particular QualType instance has the
853	/// "volatile" qualifier set, without looking through typedefs that may have
854	/// added "volatile" at a different level.
855	bool isLocalVolatileQualified() const {
856	return (getLocalFastQualifiers() & Qualifiers::Volatile);
857	}
858
859	/// Determine whether this type is volatile-qualified.
860	bool isVolatileQualified() const;
861
862	/// Determine whether this particular QualType instance has any
863	/// qualifiers, without looking through any typedefs that might add
864	/// qualifiers at a different level.
865	bool hasLocalQualifiers() const {
866	return getLocalFastQualifiers() || hasLocalNonFastQualifiers();
867	}
868
869	/// Determine whether this type has any qualifiers.
870	bool hasQualifiers() const;
871
872	/// Determine whether this particular QualType instance has any
873	/// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
874	/// instance.
875	bool hasLocalNonFastQualifiers() const {
876	return Value.getPointer().is<const ExtQuals*>();
877	}
878
879	/// Retrieve the set of qualifiers local to this particular QualType
880	/// instance, not including any qualifiers acquired through typedefs or
881	/// other sugar.
882	Qualifiers getLocalQualifiers() const;
883
884	/// Retrieve the set of qualifiers applied to this type.
885	Qualifiers getQualifiers() const;
886
887	/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
888	/// local to this particular QualType instance, not including any qualifiers
889	/// acquired through typedefs or other sugar.
890	unsigned getLocalCVRQualifiers() const {
891	return getLocalFastQualifiers();
892	}
893
894	/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
895	/// applied to this type.
896	unsigned getCVRQualifiers() const;
897
898	bool isConstant(const ASTContext& Ctx) const {
899	return QualType::isConstant(T: *this, Ctx);
900	}
901
902	/// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
903	bool isPODType(const ASTContext &Context) const;
904
905	/// Return true if this is a POD type according to the rules of the C++98
906	/// standard, regardless of the current compilation's language.
907	bool isCXX98PODType(const ASTContext &Context) const;
908
909	/// Return true if this is a POD type according to the more relaxed rules
910	/// of the C++11 standard, regardless of the current compilation's language.
911	/// (C++0x [basic.types]p9). Note that, unlike
912	/// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
913	bool isCXX11PODType(const ASTContext &Context) const;
914
915	/// Return true if this is a trivial type per (C++0x [basic.types]p9)
916	bool isTrivialType(const ASTContext &Context) const;
917
918	/// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
919	bool isTriviallyCopyableType(const ASTContext &Context) const;
920
921	/// Return true if this is a trivially copyable type
922	bool isTriviallyCopyConstructibleType(const ASTContext &Context) const;
923
924	/// Return true if this is a trivially relocatable type.
925	bool isTriviallyRelocatableType(const ASTContext &Context) const;
926
927	/// Return true if this is a trivially equality comparable type.
928	bool isTriviallyEqualityComparableType(const ASTContext &Context) const;
929
930	/// Returns true if it is a class and it might be dynamic.
931	bool mayBeDynamicClass() const;
932
933	/// Returns true if it is not a class or if the class might not be dynamic.
934	bool mayBeNotDynamicClass() const;
935
936	/// Returns true if it is a WebAssembly Reference Type.
937	bool isWebAssemblyReferenceType() const;
938
939	/// Returns true if it is a WebAssembly Externref Type.
940	bool isWebAssemblyExternrefType() const;
941
942	/// Returns true if it is a WebAssembly Funcref Type.
943	bool isWebAssemblyFuncrefType() const;
944
945	// Don't promise in the API that anything besides 'const' can be
946	// easily added.
947
948	/// Add the `const` type qualifier to this QualType.
949	void addConst() {
950	addFastQualifiers(TQs: Qualifiers::Const);
951	}
952	QualType withConst() const {
953	return withFastQualifiers(TQs: Qualifiers::Const);
954	}
955
956	/// Add the `volatile` type qualifier to this QualType.
957	void addVolatile() {
958	addFastQualifiers(TQs: Qualifiers::Volatile);
959	}
960	QualType withVolatile() const {
961	return withFastQualifiers(TQs: Qualifiers::Volatile);
962	}
963
964	/// Add the `restrict` qualifier to this QualType.
965	void addRestrict() {
966	addFastQualifiers(TQs: Qualifiers::Restrict);
967	}
968	QualType withRestrict() const {
969	return withFastQualifiers(TQs: Qualifiers::Restrict);
970	}
971
972	QualType withCVRQualifiers(unsigned CVR) const {
973	return withFastQualifiers(TQs: CVR);
974	}
975
976	void addFastQualifiers(unsigned TQs) {
977	assert(!(TQs & ~Qualifiers::FastMask)
978	&& "non-fast qualifier bits set in mask!");
979	Value.setInt(Value.getInt() | TQs);
980	}
981
982	void removeLocalConst();
983	void removeLocalVolatile();
984	void removeLocalRestrict();
985
986	void removeLocalFastQualifiers() { Value.setInt(0); }
987	void removeLocalFastQualifiers(unsigned Mask) {
988	assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers");
989	Value.setInt(Value.getInt() & ~Mask);
990	}
991
992	// Creates a type with the given qualifiers in addition to any
993	// qualifiers already on this type.
994	QualType withFastQualifiers(unsigned TQs) const {
995	QualType T = *this;
996	T.addFastQualifiers(TQs);
997	return T;
998	}
999
1000	// Creates a type with exactly the given fast qualifiers, removing
1001	// any existing fast qualifiers.
1002	QualType withExactLocalFastQualifiers(unsigned TQs) const {
1003	return withoutLocalFastQualifiers().withFastQualifiers(TQs);
1004	}
1005
1006	// Removes fast qualifiers, but leaves any extended qualifiers in place.
1007	QualType withoutLocalFastQualifiers() const {
1008	QualType T = *this;
1009	T.removeLocalFastQualifiers();
1010	return T;
1011	}
1012
1013	QualType getCanonicalType() const;
1014
1015	/// Return this type with all of the instance-specific qualifiers
1016	/// removed, but without removing any qualifiers that may have been applied
1017	/// through typedefs.
1018	QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }
1019
1020	/// Retrieve the unqualified variant of the given type,
1021	/// removing as little sugar as possible.
1022	///
1023	/// This routine looks through various kinds of sugar to find the
1024	/// least-desugared type that is unqualified. For example, given:
1025	///
1026	/// \code
1027	/// typedef int Integer;
1028	/// typedef const Integer CInteger;
1029	/// typedef CInteger DifferenceType;
1030	/// \endcode
1031	///
1032	/// Executing \c getUnqualifiedType() on the type \c DifferenceType will
1033	/// desugar until we hit the type \c Integer, which has no qualifiers on it.
1034	///
1035	/// The resulting type might still be qualified if it's sugar for an array
1036	/// type. To strip qualifiers even from within a sugared array type, use
1037	/// ASTContext::getUnqualifiedArrayType.
1038	///
1039	/// Note: In C, the _Atomic qualifier is special (see C23 6.2.5p32 for
1040	/// details), and it is not stripped by this function. Use
1041	/// getAtomicUnqualifiedType() to strip qualifiers including _Atomic.
1042	inline QualType getUnqualifiedType() const;
1043
1044	/// Retrieve the unqualified variant of the given type, removing as little
1045	/// sugar as possible.
1046	///
1047	/// Like getUnqualifiedType(), but also returns the set of
1048	/// qualifiers that were built up.
1049	///
1050	/// The resulting type might still be qualified if it's sugar for an array
1051	/// type. To strip qualifiers even from within a sugared array type, use
1052	/// ASTContext::getUnqualifiedArrayType.
1053	inline SplitQualType getSplitUnqualifiedType() const;
1054
1055	/// Determine whether this type is more qualified than the other
1056	/// given type, requiring exact equality for non-CVR qualifiers.
1057	bool isMoreQualifiedThan(QualType Other) const;
1058
1059	/// Determine whether this type is at least as qualified as the other
1060	/// given type, requiring exact equality for non-CVR qualifiers.
1061	bool isAtLeastAsQualifiedAs(QualType Other) const;
1062
1063	QualType getNonReferenceType() const;
1064
1065	/// Determine the type of a (typically non-lvalue) expression with the
1066	/// specified result type.
1067	///
1068	/// This routine should be used for expressions for which the return type is
1069	/// explicitly specified (e.g., in a cast or call) and isn't necessarily
1070	/// an lvalue. It removes a top-level reference (since there are no
1071	/// expressions of reference type) and deletes top-level cvr-qualifiers
1072	/// from non-class types (in C++) or all types (in C).
1073	QualType getNonLValueExprType(const ASTContext &Context) const;
1074
1075	/// Remove an outer pack expansion type (if any) from this type. Used as part
1076	/// of converting the type of a declaration to the type of an expression that
1077	/// references that expression. It's meaningless for an expression to have a
1078	/// pack expansion type.
1079	QualType getNonPackExpansionType() const;
1080
1081	/// Return the specified type with any "sugar" removed from
1082	/// the type. This takes off typedefs, typeof's etc. If the outer level of
1083	/// the type is already concrete, it returns it unmodified. This is similar
1084	/// to getting the canonical type, but it doesn't remove *all* typedefs. For
1085	/// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
1086	/// concrete.
1087	///
1088	/// Qualifiers are left in place.
1089	QualType getDesugaredType(const ASTContext &Context) const {
1090	return getDesugaredType(T: *this, Context);
1091	}
1092
1093	SplitQualType getSplitDesugaredType() const {
1094	return getSplitDesugaredType(T: *this);
1095	}
1096
1097	/// Return the specified type with one level of "sugar" removed from
1098	/// the type.
1099	///
1100	/// This routine takes off the first typedef, typeof, etc. If the outer level
1101	/// of the type is already concrete, it returns it unmodified.
1102	QualType getSingleStepDesugaredType(const ASTContext &Context) const {
1103	return getSingleStepDesugaredTypeImpl(type: *this, C: Context);
1104	}
1105
1106	/// Returns the specified type after dropping any
1107	/// outer-level parentheses.
1108	QualType IgnoreParens() const {
1109	if (isa<ParenType>(*this))
1110	return QualType::IgnoreParens(T: *this);
1111	return *this;
1112	}
1113
1114	/// Indicate whether the specified types and qualifiers are identical.
1115	friend bool operator==(const QualType &LHS, const QualType &RHS) {
1116	return LHS.Value == RHS.Value;
1117	}
1118	friend bool operator!=(const QualType &LHS, const QualType &RHS) {
1119	return LHS.Value != RHS.Value;
1120	}
1121	friend bool operator<(const QualType &LHS, const QualType &RHS) {
1122	return LHS.Value < RHS.Value;
1123	}
1124
1125	static std::string getAsString(SplitQualType split,
1126	const PrintingPolicy &Policy) {
1127	return getAsString(ty: split.Ty, qs: split.Quals, Policy);
1128	}
1129	static std::string getAsString(const Type *ty, Qualifiers qs,
1130	const PrintingPolicy &Policy);
1131
1132	std::string getAsString() const;
1133	std::string getAsString(const PrintingPolicy &Policy) const;
1134
1135	void print(raw_ostream &OS, const PrintingPolicy &Policy,
1136	const Twine &PlaceHolder = Twine(),
1137	unsigned Indentation = 0) const;
1138
1139	static void print(SplitQualType split, raw_ostream &OS,
1140	const PrintingPolicy &policy, const Twine &PlaceHolder,
1141	unsigned Indentation = 0) {
1142	return print(ty: split.Ty, qs: split.Quals, OS, policy, PlaceHolder, Indentation);
1143	}
1144
1145	static void print(const Type *ty, Qualifiers qs,
1146	raw_ostream &OS, const PrintingPolicy &policy,
1147	const Twine &PlaceHolder,
1148	unsigned Indentation = 0);
1149
1150	void getAsStringInternal(std::string &Str,
1151	const PrintingPolicy &Policy) const;
1152
1153	static void getAsStringInternal(SplitQualType split, std::string &out,
1154	const PrintingPolicy &policy) {
1155	return getAsStringInternal(ty: split.Ty, qs: split.Quals, out, policy);
1156	}
1157
1158	static void getAsStringInternal(const Type *ty, Qualifiers qs,
1159	std::string &out,
1160	const PrintingPolicy &policy);
1161
1162	class StreamedQualTypeHelper {
1163	const QualType &T;
1164	const PrintingPolicy &Policy;
1165	const Twine &PlaceHolder;
1166	unsigned Indentation;
1167
1168	public:
1169	StreamedQualTypeHelper(const QualType &T, const PrintingPolicy &Policy,
1170	const Twine &PlaceHolder, unsigned Indentation)
1171	: T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1172	Indentation(Indentation) {}
1173
1174	friend raw_ostream &operator<<(raw_ostream &OS,
1175	const StreamedQualTypeHelper &SQT) {
1176	SQT.T.print(OS, Policy: SQT.Policy, PlaceHolder: SQT.PlaceHolder, Indentation: SQT.Indentation);
1177	return OS;
1178	}
1179	};
1180
1181	StreamedQualTypeHelper stream(const PrintingPolicy &Policy,
1182	const Twine &PlaceHolder = Twine(),
1183	unsigned Indentation = 0) const {
1184	return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1185	}
1186
1187	void dump(const char *s) const;
1188	void dump() const;
1189	void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
1190
1191	void Profile(llvm::FoldingSetNodeID &ID) const {
1192	ID.AddPointer(Ptr: getAsOpaquePtr());
1193	}
1194
1195	/// Check if this type has any address space qualifier.
1196	inline bool hasAddressSpace() const;
1197
1198	/// Return the address space of this type.
1199	inline LangAS getAddressSpace() const;
1200
1201	/// Returns true if address space qualifiers overlap with T address space
1202	/// qualifiers.
1203	/// OpenCL C defines conversion rules for pointers to different address spaces
1204	/// and notion of overlapping address spaces.
1205	/// CL1.1 or CL1.2:
1206	/// address spaces overlap iff they are they same.
1207	/// OpenCL C v2.0 s6.5.5 adds:
1208	/// __generic overlaps with any address space except for __constant.
1209	bool isAddressSpaceOverlapping(QualType T) const {
1210	Qualifiers Q = getQualifiers();
1211	Qualifiers TQ = T.getQualifiers();
1212	// Address spaces overlap if at least one of them is a superset of another
1213	return Q.isAddressSpaceSupersetOf(other: TQ) || TQ.isAddressSpaceSupersetOf(other: Q);
1214	}
1215
1216	/// Returns gc attribute of this type.
1217	inline Qualifiers::GC getObjCGCAttr() const;
1218
1219	/// true when Type is objc's weak.
1220	bool isObjCGCWeak() const {
1221	return getObjCGCAttr() == Qualifiers::Weak;
1222	}
1223
1224	/// true when Type is objc's strong.
1225	bool isObjCGCStrong() const {
1226	return getObjCGCAttr() == Qualifiers::Strong;
1227	}
1228
1229	/// Returns lifetime attribute of this type.
1230	Qualifiers::ObjCLifetime getObjCLifetime() const {
1231	return getQualifiers().getObjCLifetime();
1232	}
1233
1234	bool hasNonTrivialObjCLifetime() const {
1235	return getQualifiers().hasNonTrivialObjCLifetime();
1236	}
1237
1238	bool hasStrongOrWeakObjCLifetime() const {
1239	return getQualifiers().hasStrongOrWeakObjCLifetime();
1240	}
1241
1242	// true when Type is objc's weak and weak is enabled but ARC isn't.
1243	bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1244
1245	enum PrimitiveDefaultInitializeKind {
1246	/// The type does not fall into any of the following categories. Note that
1247	/// this case is zero-valued so that values of this enum can be used as a
1248	/// boolean condition for non-triviality.
1249	PDIK_Trivial,
1250
1251	/// The type is an Objective-C retainable pointer type that is qualified
1252	/// with the ARC __strong qualifier.
1253	PDIK_ARCStrong,
1254
1255	/// The type is an Objective-C retainable pointer type that is qualified
1256	/// with the ARC __weak qualifier.
1257	PDIK_ARCWeak,
1258
1259	/// The type is a struct containing a field whose type is not PCK_Trivial.
1260	PDIK_Struct
1261	};
1262
1263	/// Functions to query basic properties of non-trivial C struct types.
1264
1265	/// Check if this is a non-trivial type that would cause a C struct
1266	/// transitively containing this type to be non-trivial to default initialize
1267	/// and return the kind.
1268	PrimitiveDefaultInitializeKind
1269	isNonTrivialToPrimitiveDefaultInitialize() const;
1270
1271	enum PrimitiveCopyKind {
1272	/// The type does not fall into any of the following categories. Note that
1273	/// this case is zero-valued so that values of this enum can be used as a
1274	/// boolean condition for non-triviality.
1275	PCK_Trivial,
1276
1277	/// The type would be trivial except that it is volatile-qualified. Types
1278	/// that fall into one of the other non-trivial cases may additionally be
1279	/// volatile-qualified.
1280	PCK_VolatileTrivial,
1281
1282	/// The type is an Objective-C retainable pointer type that is qualified
1283	/// with the ARC __strong qualifier.
1284	PCK_ARCStrong,
1285
1286	/// The type is an Objective-C retainable pointer type that is qualified
1287	/// with the ARC __weak qualifier.
1288	PCK_ARCWeak,
1289
1290	/// The type is a struct containing a field whose type is neither
1291	/// PCK_Trivial nor PCK_VolatileTrivial.
1292	/// Note that a C++ struct type does not necessarily match this; C++ copying
1293	/// semantics are too complex to express here, in part because they depend
1294	/// on the exact constructor or assignment operator that is chosen by
1295	/// overload resolution to do the copy.
1296	PCK_Struct
1297	};
1298
1299	/// Check if this is a non-trivial type that would cause a C struct
1300	/// transitively containing this type to be non-trivial to copy and return the
1301	/// kind.
1302	PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;
1303
1304	/// Check if this is a non-trivial type that would cause a C struct
1305	/// transitively containing this type to be non-trivial to destructively
1306	/// move and return the kind. Destructive move in this context is a C++-style
1307	/// move in which the source object is placed in a valid but unspecified state
1308	/// after it is moved, as opposed to a truly destructive move in which the
1309	/// source object is placed in an uninitialized state.
1310	PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;
1311
1312	enum DestructionKind {
1313	DK_none,
1314	DK_cxx_destructor,
1315	DK_objc_strong_lifetime,
1316	DK_objc_weak_lifetime,
1317	DK_nontrivial_c_struct
1318	};
1319
1320	/// Returns a nonzero value if objects of this type require
1321	/// non-trivial work to clean up after. Non-zero because it's
1322	/// conceivable that qualifiers (objc_gc(weak)?) could make
1323	/// something require destruction.
1324	DestructionKind isDestructedType() const {
1325	return isDestructedTypeImpl(type: *this);
1326	}
1327
1328	/// Check if this is or contains a C union that is non-trivial to
1329	/// default-initialize, which is a union that has a member that is non-trivial
1330	/// to default-initialize. If this returns true,
1331	/// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
1332	bool hasNonTrivialToPrimitiveDefaultInitializeCUnion() const;
1333
1334	/// Check if this is or contains a C union that is non-trivial to destruct,
1335	/// which is a union that has a member that is non-trivial to destruct. If
1336	/// this returns true, isDestructedType returns DK_nontrivial_c_struct.
1337	bool hasNonTrivialToPrimitiveDestructCUnion() const;
1338
1339	/// Check if this is or contains a C union that is non-trivial to copy, which
1340	/// is a union that has a member that is non-trivial to copy. If this returns
1341	/// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
1342	bool hasNonTrivialToPrimitiveCopyCUnion() const;
1343
1344	/// Determine whether expressions of the given type are forbidden
1345	/// from being lvalues in C.
1346	///
1347	/// The expression types that are forbidden to be lvalues are:
1348	/// - 'void', but not qualified void
1349	/// - function types
1350	///
1351	/// The exact rule here is C99 6.3.2.1:
1352	/// An lvalue is an expression with an object type or an incomplete
1353	/// type other than void.
1354	bool isCForbiddenLValueType() const;
1355
1356	/// Substitute type arguments for the Objective-C type parameters used in the
1357	/// subject type.
1358	///
1359	/// \param ctx ASTContext in which the type exists.
1360	///
1361	/// \param typeArgs The type arguments that will be substituted for the
1362	/// Objective-C type parameters in the subject type, which are generally
1363	/// computed via \c Type::getObjCSubstitutions. If empty, the type
1364	/// parameters will be replaced with their bounds or id/Class, as appropriate
1365	/// for the context.
1366	///
1367	/// \param context The context in which the subject type was written.
1368	///
1369	/// \returns the resulting type.
1370	QualType substObjCTypeArgs(ASTContext &ctx,
1371	ArrayRef<QualType> typeArgs,
1372	ObjCSubstitutionContext context) const;
1373
1374	/// Substitute type arguments from an object type for the Objective-C type
1375	/// parameters used in the subject type.
1376	///
1377	/// This operation combines the computation of type arguments for
1378	/// substitution (\c Type::getObjCSubstitutions) with the actual process of
1379	/// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1380	/// callers that need to perform a single substitution in isolation.
1381	///
1382	/// \param objectType The type of the object whose member type we're
1383	/// substituting into. For example, this might be the receiver of a message
1384	/// or the base of a property access.
1385	///
1386	/// \param dc The declaration context from which the subject type was
1387	/// retrieved, which indicates (for example) which type parameters should
1388	/// be substituted.
1389	///
1390	/// \param context The context in which the subject type was written.
1391	///
1392	/// \returns the subject type after replacing all of the Objective-C type
1393	/// parameters with their corresponding arguments.
1394	QualType substObjCMemberType(QualType objectType,
1395	const DeclContext *dc,
1396	ObjCSubstitutionContext context) const;
1397
1398	/// Strip Objective-C "__kindof" types from the given type.
1399	QualType stripObjCKindOfType(const ASTContext &ctx) const;
1400
1401	/// Remove all qualifiers including _Atomic.
1402	QualType getAtomicUnqualifiedType() const;
1403
1404	private:
1405	// These methods are implemented in a separate translation unit;
1406	// "static"-ize them to avoid creating temporary QualTypes in the
1407	// caller.
1408	static bool isConstant(QualType T, const ASTContext& Ctx);
1409	static QualType getDesugaredType(QualType T, const ASTContext &Context);
1410	static SplitQualType getSplitDesugaredType(QualType T);
1411	static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1412	static QualType getSingleStepDesugaredTypeImpl(QualType type,
1413	const ASTContext &C);
1414	static QualType IgnoreParens(QualType T);
1415	static DestructionKind isDestructedTypeImpl(QualType type);
1416
1417	/// Check if \param RD is or contains a non-trivial C union.
1418	static bool hasNonTrivialToPrimitiveDefaultInitializeCUnion(const RecordDecl *RD);
1419	static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
1420	static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1421	};
1422
1423	raw_ostream &operator<<(raw_ostream &OS, QualType QT);
1424
1425	} // namespace clang
1426
1427	namespace llvm {
1428
1429	/// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1430	/// to a specific Type class.
1431	template<> struct simplify_type< ::clang::QualType> {
1432	using SimpleType = const ::clang::Type *;
1433
1434	static SimpleType getSimplifiedValue(::clang::QualType Val) {
1435	return Val.getTypePtr();
1436	}
1437	};
1438
1439	// Teach SmallPtrSet that QualType is "basically a pointer".
1440	template<>
1441	struct PointerLikeTypeTraits<clang::QualType> {
1442	static inline void *getAsVoidPointer(clang::QualType P) {
1443	return P.getAsOpaquePtr();
1444	}
1445
1446	static inline clang::QualType getFromVoidPointer(void *P) {
1447	return clang::QualType::getFromOpaquePtr(Ptr: P);
1448	}
1449
1450	// Various qualifiers go in low bits.
1451	static constexpr int NumLowBitsAvailable = 0;
1452	};
1453
1454	} // namespace llvm
1455
1456	namespace clang {
1457
1458	/// Base class that is common to both the \c ExtQuals and \c Type
1459	/// classes, which allows \c QualType to access the common fields between the
1460	/// two.
1461	class ExtQualsTypeCommonBase {
1462	friend class ExtQuals;
1463	friend class QualType;
1464	friend class Type;
1465
1466	/// The "base" type of an extended qualifiers type (\c ExtQuals) or
1467	/// a self-referential pointer (for \c Type).
1468	///
1469	/// This pointer allows an efficient mapping from a QualType to its
1470	/// underlying type pointer.
1471	const Type *const BaseType;
1472
1473	/// The canonical type of this type. A QualType.
1474	QualType CanonicalType;
1475
1476	ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1477	: BaseType(baseType), CanonicalType(canon) {}
1478	};
1479
1480	/// We can encode up to four bits in the low bits of a
1481	/// type pointer, but there are many more type qualifiers that we want
1482	/// to be able to apply to an arbitrary type. Therefore we have this
1483	/// struct, intended to be heap-allocated and used by QualType to
1484	/// store qualifiers.
1485	///
1486	/// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1487	/// in three low bits on the QualType pointer; a fourth bit records whether
1488	/// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1489	/// Objective-C GC attributes) are much more rare.
1490	class alignas(TypeAlignment) ExtQuals : public ExtQualsTypeCommonBase,
1491	public llvm::FoldingSetNode {
1492	// NOTE: changing the fast qualifiers should be straightforward as
1493	// long as you don't make 'const' non-fast.
1494	// 1. Qualifiers:
1495	// a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1496	// Fast qualifiers must occupy the low-order bits.
1497	// b) Update Qualifiers::FastWidth and FastMask.
1498	// 2. QualType:
1499	// a) Update is{Volatile,Restrict}Qualified(), defined inline.
1500	// b) Update remove{Volatile,Restrict}, defined near the end of
1501	// this header.
1502	// 3. ASTContext:
1503	// a) Update get{Volatile,Restrict}Type.
1504
1505	/// The immutable set of qualifiers applied by this node. Always contains
1506	/// extended qualifiers.
1507	Qualifiers Quals;
1508
1509	ExtQuals *this_() { return this; }
1510
1511	public:
1512	ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1513	: ExtQualsTypeCommonBase(baseType,
1514	canon.isNull() ? QualType(this_(), 0) : canon),
1515	Quals(quals) {
1516	assert(Quals.hasNonFastQualifiers()
1517	&& "ExtQuals created with no fast qualifiers");
1518	assert(!Quals.hasFastQualifiers()
1519	&& "ExtQuals created with fast qualifiers");
1520	}
1521
1522	Qualifiers getQualifiers() const { return Quals; }
1523
1524	bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1525	Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1526
1527	bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1528	Qualifiers::ObjCLifetime getObjCLifetime() const {
1529	return Quals.getObjCLifetime();
1530	}
1531
1532	bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1533	LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1534
1535	const Type *getBaseType() const { return BaseType; }
1536
1537	public:
1538	void Profile(llvm::FoldingSetNodeID &ID) const {
1539	Profile(ID, BaseType: getBaseType(), Quals);
1540	}
1541
1542	static void Profile(llvm::FoldingSetNodeID &ID,
1543	const Type *BaseType,
1544	Qualifiers Quals) {
1545	assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!");
1546	ID.AddPointer(Ptr: BaseType);
1547	Quals.Profile(ID);
1548	}
1549	};
1550
1551	/// The kind of C++11 ref-qualifier associated with a function type.
1552	/// This determines whether a member function's "this" object can be an
1553	/// lvalue, rvalue, or neither.
1554	enum RefQualifierKind {
1555	/// No ref-qualifier was provided.
1556	RQ_None = 0,
1557
1558	/// An lvalue ref-qualifier was provided (\c &).
1559	RQ_LValue,
1560
1561	/// An rvalue ref-qualifier was provided (\c &&).
1562	RQ_RValue
1563	};
1564
1565	/// Which keyword(s) were used to create an AutoType.
1566	enum class AutoTypeKeyword {
1567	/// auto
1568	Auto,
1569
1570	/// decltype(auto)
1571	DecltypeAuto,
1572
1573	/// __auto_type (GNU extension)
1574	GNUAutoType
1575	};
1576
1577	enum class ArraySizeModifier;
1578	enum class ElaboratedTypeKeyword;
1579	enum class VectorKind;
1580
1581	/// The base class of the type hierarchy.
1582	///
1583	/// A central concept with types is that each type always has a canonical
1584	/// type. A canonical type is the type with any typedef names stripped out
1585	/// of it or the types it references. For example, consider:
1586	///
1587	/// typedef int foo;
1588	/// typedef foo* bar;
1589	/// 'int *' 'foo *' 'bar'
1590	///
1591	/// There will be a Type object created for 'int'. Since int is canonical, its
1592	/// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1593	/// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1594	/// there is a PointerType that represents 'int*', which, like 'int', is
1595	/// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1596	/// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1597	/// is also 'int*'.
1598	///
1599	/// Non-canonical types are useful for emitting diagnostics, without losing
1600	/// information about typedefs being used. Canonical types are useful for type
1601	/// comparisons (they allow by-pointer equality tests) and useful for reasoning
1602	/// about whether something has a particular form (e.g. is a function type),
1603	/// because they implicitly, recursively, strip all typedefs out of a type.
1604	///
1605	/// Types, once created, are immutable.
1606	///
1607	class alignas(TypeAlignment) Type : public ExtQualsTypeCommonBase {
1608	public:
1609	enum TypeClass {
1610	#define TYPE(Class, Base) Class,
1611	#define LAST_TYPE(Class) TypeLast = Class
1612	#define ABSTRACT_TYPE(Class, Base)
1613	#include "clang/AST/TypeNodes.inc"
1614	};
1615
1616	private:
1617	/// Bitfields required by the Type class.
1618	class TypeBitfields {
1619	friend class Type;
1620	template <class T> friend class TypePropertyCache;
1621
1622	/// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1623	LLVM_PREFERRED_TYPE(TypeClass)
1624	unsigned TC : 8;
1625
1626	/// Store information on the type dependency.
1627	LLVM_PREFERRED_TYPE(TypeDependence)
1628	unsigned Dependence : llvm::BitWidth<TypeDependence>;
1629
1630	/// True if the cache (i.e. the bitfields here starting with
1631	/// 'Cache') is valid.
1632	LLVM_PREFERRED_TYPE(bool)
1633	mutable unsigned CacheValid : 1;
1634
1635	/// Linkage of this type.
1636	LLVM_PREFERRED_TYPE(Linkage)
1637	mutable unsigned CachedLinkage : 3;
1638
1639	/// Whether this type involves and local or unnamed types.
1640	LLVM_PREFERRED_TYPE(bool)
1641	mutable unsigned CachedLocalOrUnnamed : 1;
1642
1643	/// Whether this type comes from an AST file.
1644	LLVM_PREFERRED_TYPE(bool)
1645	mutable unsigned FromAST : 1;
1646
1647	bool isCacheValid() const {
1648	return CacheValid;
1649	}
1650
1651	Linkage getLinkage() const {
1652	assert(isCacheValid() && "getting linkage from invalid cache");
1653	return static_cast<Linkage>(CachedLinkage);
1654	}
1655
1656	bool hasLocalOrUnnamedType() const {
1657	assert(isCacheValid() && "getting linkage from invalid cache");
1658	return CachedLocalOrUnnamed;
1659	}
1660	};
1661	enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };
1662
1663	protected:
1664	// These classes allow subclasses to somewhat cleanly pack bitfields
1665	// into Type.
1666
1667	class ArrayTypeBitfields {
1668	friend class ArrayType;
1669
1670	LLVM_PREFERRED_TYPE(TypeBitfields)
1671	unsigned : NumTypeBits;
1672
1673	/// CVR qualifiers from declarations like
1674	/// 'int X[static restrict 4]'. For function parameters only.
1675	LLVM_PREFERRED_TYPE(Qualifiers)
1676	unsigned IndexTypeQuals : 3;
1677
1678	/// Storage class qualifiers from declarations like
1679	/// 'int X[static restrict 4]'. For function parameters only.
1680	LLVM_PREFERRED_TYPE(ArraySizeModifier)
1681	unsigned SizeModifier : 3;
1682	};
1683	enum { NumArrayTypeBits = NumTypeBits + 6 };
1684
1685	class ConstantArrayTypeBitfields {
1686	friend class ConstantArrayType;
1687
1688	LLVM_PREFERRED_TYPE(ArrayTypeBitfields)
1689	unsigned : NumArrayTypeBits;
1690
1691	/// Whether we have a stored size expression.
1692	LLVM_PREFERRED_TYPE(bool)
1693	unsigned HasExternalSize : 1;
1694
1695	LLVM_PREFERRED_TYPE(unsigned)
1696	unsigned SizeWidth : 5;
1697	};
1698
1699	class BuiltinTypeBitfields {
1700	friend class BuiltinType;
1701
1702	LLVM_PREFERRED_TYPE(TypeBitfields)
1703	unsigned : NumTypeBits;
1704
1705	/// The kind (BuiltinType::Kind) of builtin type this is.
1706	static constexpr unsigned NumOfBuiltinTypeBits = 9;
1707	unsigned Kind : NumOfBuiltinTypeBits;
1708	};
1709
1710	/// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
1711	/// Only common bits are stored here. Additional uncommon bits are stored
1712	/// in a trailing object after FunctionProtoType.
1713	class FunctionTypeBitfields {
1714	friend class FunctionProtoType;
1715	friend class FunctionType;
1716
1717	LLVM_PREFERRED_TYPE(TypeBitfields)
1718	unsigned : NumTypeBits;
1719
1720	/// Extra information which affects how the function is called, like
1721	/// regparm and the calling convention.
1722	LLVM_PREFERRED_TYPE(CallingConv)
1723	unsigned ExtInfo : 13;
1724
1725	/// The ref-qualifier associated with a \c FunctionProtoType.
1726	///
1727	/// This is a value of type \c RefQualifierKind.
1728	LLVM_PREFERRED_TYPE(RefQualifierKind)
1729	unsigned RefQualifier : 2;
1730
1731	/// Used only by FunctionProtoType, put here to pack with the
1732	/// other bitfields.
1733	/// The qualifiers are part of FunctionProtoType because...
1734	///
1735	/// C++ 8.3.5p4: The return type, the parameter type list and the
1736	/// cv-qualifier-seq, [...], are part of the function type.
1737	LLVM_PREFERRED_TYPE(Qualifiers)
1738	unsigned FastTypeQuals : Qualifiers::FastWidth;
1739	/// Whether this function has extended Qualifiers.
1740	LLVM_PREFERRED_TYPE(bool)
1741	unsigned HasExtQuals : 1;
1742
1743	/// The number of parameters this function has, not counting '...'.
1744	/// According to [implimits] 8 bits should be enough here but this is
1745	/// somewhat easy to exceed with metaprogramming and so we would like to
1746	/// keep NumParams as wide as reasonably possible.
1747	unsigned NumParams : 16;
1748
1749	/// The type of exception specification this function has.
1750	LLVM_PREFERRED_TYPE(ExceptionSpecificationType)
1751	unsigned ExceptionSpecType : 4;
1752
1753	/// Whether this function has extended parameter information.
1754	LLVM_PREFERRED_TYPE(bool)
1755	unsigned HasExtParameterInfos : 1;
1756
1757	/// Whether this function has extra bitfields for the prototype.
1758	LLVM_PREFERRED_TYPE(bool)
1759	unsigned HasExtraBitfields : 1;
1760
1761	/// Whether the function is variadic.
1762	LLVM_PREFERRED_TYPE(bool)
1763	unsigned Variadic : 1;
1764
1765	/// Whether this function has a trailing return type.
1766	LLVM_PREFERRED_TYPE(bool)
1767	unsigned HasTrailingReturn : 1;
1768	};
1769
1770	class ObjCObjectTypeBitfields {
1771	friend class ObjCObjectType;
1772
1773	LLVM_PREFERRED_TYPE(TypeBitfields)
1774	unsigned : NumTypeBits;
1775
1776	/// The number of type arguments stored directly on this object type.
1777	unsigned NumTypeArgs : 7;
1778
1779	/// The number of protocols stored directly on this object type.
1780	unsigned NumProtocols : 6;
1781
1782	/// Whether this is a "kindof" type.
1783	LLVM_PREFERRED_TYPE(bool)
1784	unsigned IsKindOf : 1;
1785	};
1786
1787	class ReferenceTypeBitfields {
1788	friend class ReferenceType;
1789
1790	LLVM_PREFERRED_TYPE(TypeBitfields)
1791	unsigned : NumTypeBits;
1792
1793	/// True if the type was originally spelled with an lvalue sigil.
1794	/// This is never true of rvalue references but can also be false
1795	/// on lvalue references because of C++0x [dcl.typedef]p9,
1796	/// as follows:
1797	///
1798	/// typedef int &ref; // lvalue, spelled lvalue
1799	/// typedef int &&rvref; // rvalue
1800	/// ref &a; // lvalue, inner ref, spelled lvalue
1801	/// ref &&a; // lvalue, inner ref
1802	/// rvref &a; // lvalue, inner ref, spelled lvalue
1803	/// rvref &&a; // rvalue, inner ref
1804	LLVM_PREFERRED_TYPE(bool)
1805	unsigned SpelledAsLValue : 1;
1806
1807	/// True if the inner type is a reference type. This only happens
1808	/// in non-canonical forms.
1809	LLVM_PREFERRED_TYPE(bool)
1810	unsigned InnerRef : 1;
1811	};
1812
1813	class TypeWithKeywordBitfields {
1814	friend class TypeWithKeyword;
1815
1816	LLVM_PREFERRED_TYPE(TypeBitfields)
1817	unsigned : NumTypeBits;
1818
1819	/// An ElaboratedTypeKeyword. 8 bits for efficient access.
1820	LLVM_PREFERRED_TYPE(ElaboratedTypeKeyword)
1821	unsigned Keyword : 8;
1822	};
1823
1824	enum { NumTypeWithKeywordBits = NumTypeBits + 8 };
1825
1826	class ElaboratedTypeBitfields {
1827	friend class ElaboratedType;
1828
1829	LLVM_PREFERRED_TYPE(TypeWithKeywordBitfields)
1830	unsigned : NumTypeWithKeywordBits;
1831
1832	/// Whether the ElaboratedType has a trailing OwnedTagDecl.
1833	LLVM_PREFERRED_TYPE(bool)
1834	unsigned HasOwnedTagDecl : 1;
1835	};
1836
1837	class VectorTypeBitfields {
1838	friend class VectorType;
1839	friend class DependentVectorType;
1840
1841	LLVM_PREFERRED_TYPE(TypeBitfields)
1842	unsigned : NumTypeBits;
1843
1844	/// The kind of vector, either a generic vector type or some
1845	/// target-specific vector type such as for AltiVec or Neon.
1846	LLVM_PREFERRED_TYPE(VectorKind)
1847	unsigned VecKind : 4;
1848	/// The number of elements in the vector.
1849	uint32_t NumElements;
1850	};
1851
1852	class AttributedTypeBitfields {
1853	friend class AttributedType;
1854
1855	LLVM_PREFERRED_TYPE(TypeBitfields)
1856	unsigned : NumTypeBits;
1857
1858	LLVM_PREFERRED_TYPE(attr::Kind)
1859	unsigned AttrKind : 32 - NumTypeBits;
1860	};
1861
1862	class AutoTypeBitfields {
1863	friend class AutoType;
1864
1865	LLVM_PREFERRED_TYPE(TypeBitfields)
1866	unsigned : NumTypeBits;
1867
1868	/// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1869	/// or '__auto_type'? AutoTypeKeyword value.
1870	LLVM_PREFERRED_TYPE(AutoTypeKeyword)
1871	unsigned Keyword : 2;
1872
1873	/// The number of template arguments in the type-constraints, which is
1874	/// expected to be able to hold at least 1024 according to [implimits].
1875	/// However as this limit is somewhat easy to hit with template
1876	/// metaprogramming we'd prefer to keep it as large as possible.
1877	/// At the moment it has been left as a non-bitfield since this type
1878	/// safely fits in 64 bits as an unsigned, so there is no reason to
1879	/// introduce the performance impact of a bitfield.
1880	unsigned NumArgs;
1881	};
1882
1883	class TypeOfBitfields {
1884	friend class TypeOfType;
1885	friend class TypeOfExprType;
1886
1887	LLVM_PREFERRED_TYPE(TypeBitfields)
1888	unsigned : NumTypeBits;
1889	LLVM_PREFERRED_TYPE(bool)
1890	unsigned IsUnqual : 1; // If true: typeof_unqual, else: typeof
1891	};
1892
1893	class UsingBitfields {
1894	friend class UsingType;
1895
1896	LLVM_PREFERRED_TYPE(TypeBitfields)
1897	unsigned : NumTypeBits;
1898
1899	/// True if the underlying type is different from the declared one.
1900	LLVM_PREFERRED_TYPE(bool)
1901	unsigned hasTypeDifferentFromDecl : 1;
1902	};
1903
1904	class TypedefBitfields {
1905	friend class TypedefType;
1906
1907	LLVM_PREFERRED_TYPE(TypeBitfields)
1908	unsigned : NumTypeBits;
1909
1910	/// True if the underlying type is different from the declared one.
1911	LLVM_PREFERRED_TYPE(bool)
1912	unsigned hasTypeDifferentFromDecl : 1;
1913	};
1914
1915	class SubstTemplateTypeParmTypeBitfields {
1916	friend class SubstTemplateTypeParmType;
1917
1918	LLVM_PREFERRED_TYPE(TypeBitfields)
1919	unsigned : NumTypeBits;
1920
1921	LLVM_PREFERRED_TYPE(bool)
1922	unsigned HasNonCanonicalUnderlyingType : 1;
1923
1924	// The index of the template parameter this substitution represents.
1925	unsigned Index : 15;
1926
1927	/// Represents the index within a pack if this represents a substitution
1928	/// from a pack expansion. This index starts at the end of the pack and
1929	/// increments towards the beginning.
1930	/// Positive non-zero number represents the index + 1.
1931	/// Zero means this is not substituted from an expansion.
1932	unsigned PackIndex : 16;
1933	};
1934
1935	class SubstTemplateTypeParmPackTypeBitfields {
1936	friend class SubstTemplateTypeParmPackType;
1937
1938	LLVM_PREFERRED_TYPE(TypeBitfields)
1939	unsigned : NumTypeBits;
1940
1941	// The index of the template parameter this substitution represents.
1942	unsigned Index : 16;
1943
1944	/// The number of template arguments in \c Arguments, which is
1945	/// expected to be able to hold at least 1024 according to [implimits].
1946	/// However as this limit is somewhat easy to hit with template
1947	/// metaprogramming we'd prefer to keep it as large as possible.
1948	unsigned NumArgs : 16;
1949	};
1950
1951	class TemplateSpecializationTypeBitfields {
1952	friend class TemplateSpecializationType;
1953
1954	LLVM_PREFERRED_TYPE(TypeBitfields)
1955	unsigned : NumTypeBits;
1956
1957	/// Whether this template specialization type is a substituted type alias.
1958	LLVM_PREFERRED_TYPE(bool)
1959	unsigned TypeAlias : 1;
1960
1961	/// The number of template arguments named in this class template
1962	/// specialization, which is expected to be able to hold at least 1024
1963	/// according to [implimits]. However, as this limit is somewhat easy to
1964	/// hit with template metaprogramming we'd prefer to keep it as large
1965	/// as possible. At the moment it has been left as a non-bitfield since
1966	/// this type safely fits in 64 bits as an unsigned, so there is no reason
1967	/// to introduce the performance impact of a bitfield.
1968	unsigned NumArgs;
1969	};
1970
1971	class DependentTemplateSpecializationTypeBitfields {
1972	friend class DependentTemplateSpecializationType;
1973
1974	LLVM_PREFERRED_TYPE(TypeWithKeywordBitfields)
1975	unsigned : NumTypeWithKeywordBits;
1976
1977	/// The number of template arguments named in this class template
1978	/// specialization, which is expected to be able to hold at least 1024
1979	/// according to [implimits]. However, as this limit is somewhat easy to
1980	/// hit with template metaprogramming we'd prefer to keep it as large
1981	/// as possible. At the moment it has been left as a non-bitfield since
1982	/// this type safely fits in 64 bits as an unsigned, so there is no reason
1983	/// to introduce the performance impact of a bitfield.
1984	unsigned NumArgs;
1985	};
1986
1987	class PackExpansionTypeBitfields {
1988	friend class PackExpansionType;
1989
1990	LLVM_PREFERRED_TYPE(TypeBitfields)
1991	unsigned : NumTypeBits;
1992
1993	/// The number of expansions that this pack expansion will
1994	/// generate when substituted (+1), which is expected to be able to
1995	/// hold at least 1024 according to [implimits]. However, as this limit
1996	/// is somewhat easy to hit with template metaprogramming we'd prefer to
1997	/// keep it as large as possible. At the moment it has been left as a
1998	/// non-bitfield since this type safely fits in 64 bits as an unsigned, so
1999	/// there is no reason to introduce the performance impact of a bitfield.
2000	///
2001	/// This field will only have a non-zero value when some of the parameter
2002	/// packs that occur within the pattern have been substituted but others
2003	/// have not.
2004	unsigned NumExpansions;
2005	};
2006
2007	class CountAttributedTypeBitfields {
2008	friend class CountAttributedType;
2009
2010	LLVM_PREFERRED_TYPE(TypeBitfields)
2011	unsigned : NumTypeBits;
2012
2013	static constexpr unsigned NumCoupledDeclsBits = 4;
2014	unsigned NumCoupledDecls : NumCoupledDeclsBits;
2015	LLVM_PREFERRED_TYPE(bool)
2016	unsigned CountInBytes : 1;
2017	LLVM_PREFERRED_TYPE(bool)
2018	unsigned OrNull : 1;
2019	};
2020	static_assert(sizeof(CountAttributedTypeBitfields) <= sizeof(unsigned));
2021
2022	union {
2023	TypeBitfields TypeBits;
2024	ArrayTypeBitfields ArrayTypeBits;
2025	ConstantArrayTypeBitfields ConstantArrayTypeBits;
2026	AttributedTypeBitfields AttributedTypeBits;
2027	AutoTypeBitfields AutoTypeBits;
2028	TypeOfBitfields TypeOfBits;
2029	TypedefBitfields TypedefBits;
2030	UsingBitfields UsingBits;
2031	BuiltinTypeBitfields BuiltinTypeBits;
2032	FunctionTypeBitfields FunctionTypeBits;
2033	ObjCObjectTypeBitfields ObjCObjectTypeBits;
2034	ReferenceTypeBitfields ReferenceTypeBits;
2035	TypeWithKeywordBitfields TypeWithKeywordBits;
2036	ElaboratedTypeBitfields ElaboratedTypeBits;
2037	VectorTypeBitfields VectorTypeBits;
2038	SubstTemplateTypeParmTypeBitfields SubstTemplateTypeParmTypeBits;
2039	SubstTemplateTypeParmPackTypeBitfields SubstTemplateTypeParmPackTypeBits;
2040	TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits;
2041	DependentTemplateSpecializationTypeBitfields
2042	DependentTemplateSpecializationTypeBits;
2043	PackExpansionTypeBitfields PackExpansionTypeBits;
2044	CountAttributedTypeBitfields CountAttributedTypeBits;
2045	};
2046
2047	private:
2048	template <class T> friend class TypePropertyCache;
2049
2050	/// Set whether this type comes from an AST file.
2051	void setFromAST(bool V = true) const {
2052	TypeBits.FromAST = V;
2053	}
2054
2055	protected:
2056	friend class ASTContext;
2057
2058	Type(TypeClass tc, QualType canon, TypeDependence Dependence)
2059	: ExtQualsTypeCommonBase(this,
2060	canon.isNull() ? QualType(this_(), 0) : canon) {
2061	static_assert(sizeof(*this) <=
2062	alignof(decltype(*this)) + sizeof(ExtQualsTypeCommonBase),
2063	"changing bitfields changed sizeof(Type)!");
2064	static_assert(alignof(decltype(*this)) % TypeAlignment == 0,
2065	"Insufficient alignment!");
2066	TypeBits.TC = tc;
2067	TypeBits.Dependence = static_cast<unsigned>(Dependence);
2068	TypeBits.CacheValid = false;
2069	TypeBits.CachedLocalOrUnnamed = false;
2070	TypeBits.CachedLinkage = llvm::to_underlying(Linkage::Invalid);
2071	TypeBits.FromAST = false;
2072	}
2073
2074	// silence VC++ warning C4355: 'this' : used in base member initializer list
2075	Type *this_() { return this; }
2076
2077	void setDependence(TypeDependence D) {
2078	TypeBits.Dependence = static_cast<unsigned>(D);
2079	}
2080
2081	void addDependence(TypeDependence D) { setDependence(getDependence() | D); }
2082
2083	public:
2084	friend class ASTReader;
2085	friend class ASTWriter;
2086	template <class T> friend class serialization::AbstractTypeReader;
2087	template <class T> friend class serialization::AbstractTypeWriter;
2088
2089	Type(const Type &) = delete;
2090	Type(Type &&) = delete;
2091	Type &operator=(const Type &) = delete;
2092	Type &operator=(Type &&) = delete;
2093
2094	TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
2095
2096	/// Whether this type comes from an AST file.
2097	bool isFromAST() const { return TypeBits.FromAST; }
2098
2099	/// Whether this type is or contains an unexpanded parameter
2100	/// pack, used to support C++0x variadic templates.
2101	///
2102	/// A type that contains a parameter pack shall be expanded by the
2103	/// ellipsis operator at some point. For example, the typedef in the
2104	/// following example contains an unexpanded parameter pack 'T':
2105	///
2106	/// \code
2107	/// template<typename ...T>
2108	/// struct X {
2109	/// typedef T* pointer_types; // ill-formed; T is a parameter pack.
2110	/// };
2111	/// \endcode
2112	///
2113	/// Note that this routine does not specify which
2114	bool containsUnexpandedParameterPack() const {
2115	return getDependence() & TypeDependence::UnexpandedPack;
2116	}
2117
2118	/// Determines if this type would be canonical if it had no further
2119	/// qualification.
2120	bool isCanonicalUnqualified() const {
2121	return CanonicalType == QualType(this, 0);
2122	}
2123
2124	/// Pull a single level of sugar off of this locally-unqualified type.
2125	/// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
2126	/// or QualType::getSingleStepDesugaredType(const ASTContext&).
2127	QualType getLocallyUnqualifiedSingleStepDesugaredType() const;
2128
2129	/// As an extension, we classify types as one of "sized" or "sizeless";
2130	/// every type is one or the other. Standard types are all sized;
2131	/// sizeless types are purely an extension.
2132	///
2133	/// Sizeless types contain data with no specified size, alignment,
2134	/// or layout.
2135	bool isSizelessType() const;
2136	bool isSizelessBuiltinType() const;
2137
2138	/// Returns true for all scalable vector types.
2139	bool isSizelessVectorType() const;
2140
2141	/// Returns true for SVE scalable vector types.
2142	bool isSVESizelessBuiltinType() const;
2143
2144	/// Returns true for RVV scalable vector types.
2145	bool isRVVSizelessBuiltinType() const;
2146
2147	/// Check if this is a WebAssembly Externref Type.
2148	bool isWebAssemblyExternrefType() const;
2149
2150	/// Returns true if this is a WebAssembly table type: either an array of
2151	/// reference types, or a pointer to a reference type (which can only be
2152	/// created by array to pointer decay).
2153	bool isWebAssemblyTableType() const;
2154
2155	/// Determines if this is a sizeless type supported by the
2156	/// 'arm_sve_vector_bits' type attribute, which can be applied to a single
2157	/// SVE vector or predicate, excluding tuple types such as svint32x4_t.
2158	bool isSveVLSBuiltinType() const;
2159
2160	/// Returns the representative type for the element of an SVE builtin type.
2161	/// This is used to represent fixed-length SVE vectors created with the
2162	/// 'arm_sve_vector_bits' type attribute as VectorType.
2163	QualType getSveEltType(const ASTContext &Ctx) const;
2164
2165	/// Determines if this is a sizeless type supported by the
2166	/// 'riscv_rvv_vector_bits' type attribute, which can be applied to a single
2167	/// RVV vector or mask.
2168	bool isRVVVLSBuiltinType() const;
2169
2170	/// Returns the representative type for the element of an RVV builtin type.
2171	/// This is used to represent fixed-length RVV vectors created with the
2172	/// 'riscv_rvv_vector_bits' type attribute as VectorType.
2173	QualType getRVVEltType(const ASTContext &Ctx) const;
2174
2175	/// Types are partitioned into 3 broad categories (C99 6.2.5p1):
2176	/// object types, function types, and incomplete types.
2177
2178	/// Return true if this is an incomplete type.
2179	/// A type that can describe objects, but which lacks information needed to
2180	/// determine its size (e.g. void, or a fwd declared struct). Clients of this
2181	/// routine will need to determine if the size is actually required.
2182	///
2183	/// Def If non-null, and the type refers to some kind of declaration
2184	/// that can be completed (such as a C struct, C++ class, or Objective-C
2185	/// class), will be set to the declaration.
2186	bool isIncompleteType(NamedDecl **Def = nullptr) const;
2187
2188	/// Return true if this is an incomplete or object
2189	/// type, in other words, not a function type.
2190	bool isIncompleteOrObjectType() const {
2191	return !isFunctionType();
2192	}
2193
2194	/// Determine whether this type is an object type.
2195	bool isObjectType() const {
2196	// C++ [basic.types]p8:
2197	// An object type is a (possibly cv-qualified) type that is not a
2198	// function type, not a reference type, and not a void type.
2199	return !isReferenceType() && !isFunctionType() && !isVoidType();
2200	}
2201
2202	/// Return true if this is a literal type
2203	/// (C++11 [basic.types]p10)
2204	bool isLiteralType(const ASTContext &Ctx) const;
2205
2206	/// Determine if this type is a structural type, per C++20 [temp.param]p7.
2207	bool isStructuralType() const;
2208
2209	/// Test if this type is a standard-layout type.
2210	/// (C++0x [basic.type]p9)
2211	bool isStandardLayoutType() const;
2212
2213	/// Helper methods to distinguish type categories. All type predicates
2214	/// operate on the canonical type, ignoring typedefs and qualifiers.
2215
2216	/// Returns true if the type is a builtin type.
2217	bool isBuiltinType() const;
2218
2219	/// Test for a particular builtin type.
2220	bool isSpecificBuiltinType(unsigned K) const;
2221
2222	/// Test for a type which does not represent an actual type-system type but
2223	/// is instead used as a placeholder for various convenient purposes within
2224	/// Clang. All such types are BuiltinTypes.
2225	bool isPlaceholderType() const;
2226	const BuiltinType *getAsPlaceholderType() const;
2227
2228	/// Test for a specific placeholder type.
2229	bool isSpecificPlaceholderType(unsigned K) const;
2230
2231	/// Test for a placeholder type other than Overload; see
2232	/// BuiltinType::isNonOverloadPlaceholderType.
2233	bool isNonOverloadPlaceholderType() const;
2234
2235	/// isIntegerType() does *not* include complex integers (a GCC extension).
2236	/// isComplexIntegerType() can be used to test for complex integers.
2237	bool isIntegerType() const; // C99 6.2.5p17 (int, char, bool, enum)
2238	bool isEnumeralType() const;
2239
2240	/// Determine whether this type is a scoped enumeration type.
2241	bool isScopedEnumeralType() const;
2242	bool isBooleanType() const;
2243	bool isCharType() const;
2244	bool isWideCharType() const;
2245	bool isChar8Type() const;
2246	bool isChar16Type() const;
2247	bool isChar32Type() const;
2248	bool isAnyCharacterType() const;
2249	bool isIntegralType(const ASTContext &Ctx) const;
2250
2251	/// Determine whether this type is an integral or enumeration type.
2252	bool isIntegralOrEnumerationType() const;
2253
2254	/// Determine whether this type is an integral or unscoped enumeration type.
2255	bool isIntegralOrUnscopedEnumerationType() const;
2256	bool isUnscopedEnumerationType() const;
2257
2258	/// Floating point categories.
2259	bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
2260	/// isComplexType() does *not* include complex integers (a GCC extension).
2261	/// isComplexIntegerType() can be used to test for complex integers.
2262	bool isComplexType() const; // C99 6.2.5p11 (complex)
2263	bool isAnyComplexType() const; // C99 6.2.5p11 (complex) + Complex Int.
2264	bool isFloatingType() const; // C99 6.2.5p11 (real floating + complex)
2265	bool isHalfType() const; // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
2266	bool isFloat16Type() const; // C11 extension ISO/IEC TS 18661
2267	bool isFloat32Type() const;
2268	bool isDoubleType() const;
2269	bool isBFloat16Type() const;
2270	bool isFloat128Type() const;
2271	bool isIbm128Type() const;
2272	bool isRealType() const; // C99 6.2.5p17 (real floating + integer)
2273	bool isArithmeticType() const; // C99 6.2.5p18 (integer + floating)
2274	bool isVoidType() const; // C99 6.2.5p19
2275	bool isScalarType() const; // C99 6.2.5p21 (arithmetic + pointers)
2276	bool isAggregateType() const;
2277	bool isFundamentalType() const;
2278	bool isCompoundType() const;
2279
2280	// Type Predicates: Check to see if this type is structurally the specified
2281	// type, ignoring typedefs and qualifiers.
2282	bool isFunctionType() const;
2283	bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
2284	bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
2285	bool isPointerType() const;
2286	bool isAnyPointerType() const; // Any C pointer or ObjC object pointer
2287	bool isCountAttributedType() const;
2288	bool isBlockPointerType() const;
2289	bool isVoidPointerType() const;
2290	bool isReferenceType() const;
2291	bool isLValueReferenceType() const;
2292	bool isRValueReferenceType() const;
2293	bool isObjectPointerType() const;
2294	bool isFunctionPointerType() const;
2295	bool isFunctionReferenceType() const;
2296	bool isMemberPointerType() const;
2297	bool isMemberFunctionPointerType() const;
2298	bool isMemberDataPointerType() const;
2299	bool isArrayType() const;
2300	bool isConstantArrayType() const;
2301	bool isIncompleteArrayType() const;
2302	bool isVariableArrayType() const;
2303	bool isArrayParameterType() const;
2304	bool isDependentSizedArrayType() const;
2305	bool isRecordType() const;
2306	bool isClassType() const;
2307	bool isStructureType() const;
2308	bool isObjCBoxableRecordType() const;
2309	bool isInterfaceType() const;
2310	bool isStructureOrClassType() const;
2311	bool isUnionType() const;
2312	bool isComplexIntegerType() const; // GCC _Complex integer type.
2313	bool isVectorType() const; // GCC vector type.
2314	bool isExtVectorType() const; // Extended vector type.
2315	bool isExtVectorBoolType() const; // Extended vector type with bool element.
2316	bool isMatrixType() const; // Matrix type.
2317	bool isConstantMatrixType() const; // Constant matrix type.
2318	bool isDependentAddressSpaceType() const; // value-dependent address space qualifier
2319	bool isObjCObjectPointerType() const; // pointer to ObjC object
2320	bool isObjCRetainableType() const; // ObjC object or block pointer
2321	bool isObjCLifetimeType() const; // (array of)* retainable type
2322	bool isObjCIndirectLifetimeType() const; // (pointer to)* lifetime type
2323	bool isObjCNSObjectType() const; // __attribute__((NSObject))
2324	bool isObjCIndependentClassType() const; // __attribute__((objc_independent_class))
2325	// FIXME: change this to 'raw' interface type, so we can used 'interface' type
2326	// for the common case.
2327	bool isObjCObjectType() const; // NSString or typeof(*(id)0)
2328	bool isObjCQualifiedInterfaceType() const; // NSString<foo>
2329	bool isObjCQualifiedIdType() const; // id<foo>
2330	bool isObjCQualifiedClassType() const; // Class<foo>
2331	bool isObjCObjectOrInterfaceType() const;
2332	bool isObjCIdType() const; // id
2333	bool isDecltypeType() const;
2334	/// Was this type written with the special inert-in-ARC __unsafe_unretained
2335	/// qualifier?
2336	///
2337	/// This approximates the answer to the following question: if this
2338	/// translation unit were compiled in ARC, would this type be qualified
2339	/// with __unsafe_unretained?
2340	bool isObjCInertUnsafeUnretainedType() const {
2341	return hasAttr(attr::ObjCInertUnsafeUnretained);
2342	}
2343
2344	/// Whether the type is Objective-C 'id' or a __kindof type of an
2345	/// object type, e.g., __kindof NSView * or __kindof id
2346	/// <NSCopying>.
2347	///
2348	/// \param bound Will be set to the bound on non-id subtype types,
2349	/// which will be (possibly specialized) Objective-C class type, or
2350	/// null for 'id.
2351	bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
2352	const ObjCObjectType *&bound) const;
2353
2354	bool isObjCClassType() const; // Class
2355
2356	/// Whether the type is Objective-C 'Class' or a __kindof type of an
2357	/// Class type, e.g., __kindof Class <NSCopying>.
2358	///
2359	/// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
2360	/// here because Objective-C's type system cannot express "a class
2361	/// object for a subclass of NSFoo".
2362	bool isObjCClassOrClassKindOfType() const;
2363
2364	bool isBlockCompatibleObjCPointerType(ASTContext &ctx) const;
2365	bool isObjCSelType() const; // Class
2366	bool isObjCBuiltinType() const; // 'id' or 'Class'
2367	bool isObjCARCBridgableType() const;
2368	bool isCARCBridgableType() const;
2369	bool isTemplateTypeParmType() const; // C++ template type parameter
2370	bool isNullPtrType() const; // C++11 std::nullptr_t or
2371	// C23 nullptr_t
2372	bool isNothrowT() const; // C++ std::nothrow_t
2373	bool isAlignValT() const; // C++17 std::align_val_t
2374	bool isStdByteType() const; // C++17 std::byte
2375	bool isAtomicType() const; // C11 _Atomic()
2376	bool isUndeducedAutoType() const; // C++11 auto or
2377	// C++14 decltype(auto)
2378	bool isTypedefNameType() const; // typedef or alias template
2379
2380	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
2381	bool is##Id##Type() const;
2382	#include "clang/Basic/OpenCLImageTypes.def"
2383
2384	bool isImageType() const; // Any OpenCL image type
2385
2386	bool isSamplerT() const; // OpenCL sampler_t
2387	bool isEventT() const; // OpenCL event_t
2388	bool isClkEventT() const; // OpenCL clk_event_t
2389	bool isQueueT() const; // OpenCL queue_t
2390	bool isReserveIDT() const; // OpenCL reserve_id_t
2391
2392	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
2393	bool is##Id##Type() const;
2394	#include "clang/Basic/OpenCLExtensionTypes.def"
2395	// Type defined in cl_intel_device_side_avc_motion_estimation OpenCL extension
2396	bool isOCLIntelSubgroupAVCType() const;
2397	bool isOCLExtOpaqueType() const; // Any OpenCL extension type
2398
2399	bool isPipeType() const; // OpenCL pipe type
2400	bool isBitIntType() const; // Bit-precise integer type
2401	bool isOpenCLSpecificType() const; // Any OpenCL specific type
2402
2403	/// Determines if this type, which must satisfy
2404	/// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
2405	/// than implicitly __strong.
2406	bool isObjCARCImplicitlyUnretainedType() const;
2407
2408	/// Check if the type is the CUDA device builtin surface type.
2409	bool isCUDADeviceBuiltinSurfaceType() const;
2410	/// Check if the type is the CUDA device builtin texture type.
2411	bool isCUDADeviceBuiltinTextureType() const;
2412
2413	/// Return the implicit lifetime for this type, which must not be dependent.
2414	Qualifiers::ObjCLifetime getObjCARCImplicitLifetime() const;
2415
2416	enum ScalarTypeKind {
2417	STK_CPointer,
2418	STK_BlockPointer,
2419	STK_ObjCObjectPointer,
2420	STK_MemberPointer,
2421	STK_Bool,
2422	STK_Integral,
2423	STK_Floating,
2424	STK_IntegralComplex,
2425	STK_FloatingComplex,
2426	STK_FixedPoint
2427	};
2428
2429	/// Given that this is a scalar type, classify it.
2430	ScalarTypeKind getScalarTypeKind() const;
2431
2432	TypeDependence getDependence() const {
2433	return static_cast<TypeDependence>(TypeBits.Dependence);
2434	}
2435
2436	/// Whether this type is an error type.
2437	bool containsErrors() const {
2438	return getDependence() & TypeDependence::Error;
2439	}
2440
2441	/// Whether this type is a dependent type, meaning that its definition
2442	/// somehow depends on a template parameter (C++ [temp.dep.type]).
2443	bool isDependentType() const {
2444	return getDependence() & TypeDependence::Dependent;
2445	}
2446
2447	/// Determine whether this type is an instantiation-dependent type,
2448	/// meaning that the type involves a template parameter (even if the
2449	/// definition does not actually depend on the type substituted for that
2450	/// template parameter).
2451	bool isInstantiationDependentType() const {
2452	return getDependence() & TypeDependence::Instantiation;
2453	}
2454
2455	/// Determine whether this type is an undeduced type, meaning that
2456	/// it somehow involves a C++11 'auto' type or similar which has not yet been
2457	/// deduced.
2458	bool isUndeducedType() const;
2459
2460	/// Whether this type is a variably-modified type (C99 6.7.5).
2461	bool isVariablyModifiedType() const {
2462	return getDependence() & TypeDependence::VariablyModified;
2463	}
2464
2465	/// Whether this type involves a variable-length array type
2466	/// with a definite size.
2467	bool hasSizedVLAType() const;
2468
2469	/// Whether this type is or contains a local or unnamed type.
2470	bool hasUnnamedOrLocalType() const;
2471
2472	bool isOverloadableType() const;
2473
2474	/// Determine wither this type is a C++ elaborated-type-specifier.
2475	bool isElaboratedTypeSpecifier() const;
2476
2477	bool canDecayToPointerType() const;
2478
2479	/// Whether this type is represented natively as a pointer. This includes
2480	/// pointers, references, block pointers, and Objective-C interface,
2481	/// qualified id, and qualified interface types, as well as nullptr_t.
2482	bool hasPointerRepresentation() const;
2483
2484	/// Whether this type can represent an objective pointer type for the
2485	/// purpose of GC'ability
2486	bool hasObjCPointerRepresentation() const;
2487
2488	/// Determine whether this type has an integer representation
2489	/// of some sort, e.g., it is an integer type or a vector.
2490	bool hasIntegerRepresentation() const;
2491
2492	/// Determine whether this type has an signed integer representation
2493	/// of some sort, e.g., it is an signed integer type or a vector.
2494	bool hasSignedIntegerRepresentation() const;
2495
2496	/// Determine whether this type has an unsigned integer representation
2497	/// of some sort, e.g., it is an unsigned integer type or a vector.
2498	bool hasUnsignedIntegerRepresentation() const;
2499
2500	/// Determine whether this type has a floating-point representation
2501	/// of some sort, e.g., it is a floating-point type or a vector thereof.
2502	bool hasFloatingRepresentation() const;
2503
2504	// Type Checking Functions: Check to see if this type is structurally the
2505	// specified type, ignoring typedefs and qualifiers, and return a pointer to
2506	// the best type we can.
2507	const RecordType *getAsStructureType() const;
2508	/// NOTE: getAs*ArrayType are methods on ASTContext.
2509	const RecordType *getAsUnionType() const;
2510	const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
2511	const ObjCObjectType *getAsObjCInterfaceType() const;
2512
2513	// The following is a convenience method that returns an ObjCObjectPointerType
2514	// for object declared using an interface.
2515	const ObjCObjectPointerType *getAsObjCInterfacePointerType() const;
2516	const ObjCObjectPointerType *getAsObjCQualifiedIdType() const;
2517	const ObjCObjectPointerType *getAsObjCQualifiedClassType() const;
2518	const ObjCObjectType *getAsObjCQualifiedInterfaceType() const;
2519
2520	/// Retrieves the CXXRecordDecl that this type refers to, either
2521	/// because the type is a RecordType or because it is the injected-class-name
2522	/// type of a class template or class template partial specialization.
2523	CXXRecordDecl *getAsCXXRecordDecl() const;
2524
2525	/// Retrieves the RecordDecl this type refers to.
2526	RecordDecl *getAsRecordDecl() const;
2527
2528	/// Retrieves the TagDecl that this type refers to, either
2529	/// because the type is a TagType or because it is the injected-class-name
2530	/// type of a class template or class template partial specialization.
2531	TagDecl *getAsTagDecl() const;
2532
2533	/// If this is a pointer or reference to a RecordType, return the
2534	/// CXXRecordDecl that the type refers to.
2535	///
2536	/// If this is not a pointer or reference, or the type being pointed to does
2537	/// not refer to a CXXRecordDecl, returns NULL.
2538	const CXXRecordDecl *getPointeeCXXRecordDecl() const;
2539
2540	/// Get the DeducedType whose type will be deduced for a variable with
2541	/// an initializer of this type. This looks through declarators like pointer
2542	/// types, but not through decltype or typedefs.
2543	DeducedType *getContainedDeducedType() const;
2544
2545	/// Get the AutoType whose type will be deduced for a variable with
2546	/// an initializer of this type. This looks through declarators like pointer
2547	/// types, but not through decltype or typedefs.
2548	AutoType *getContainedAutoType() const {
2549	return dyn_cast_or_null<AutoType>(getContainedDeducedType());
2550	}
2551
2552	/// Determine whether this type was written with a leading 'auto'
2553	/// corresponding to a trailing return type (possibly for a nested
2554	/// function type within a pointer to function type or similar).
2555	bool hasAutoForTrailingReturnType() const;
2556
2557	/// Member-template getAs<specific type>'. Look through sugar for
2558	/// an instance of \<specific type>. This scheme will eventually
2559	/// replace the specific getAsXXXX methods above.
2560	///
2561	/// There are some specializations of this member template listed
2562	/// immediately following this class.
2563	template <typename T> const T *getAs() const;
2564
2565	/// Member-template getAsAdjusted<specific type>. Look through specific kinds
2566	/// of sugar (parens, attributes, etc) for an instance of \<specific type>.
2567	/// This is used when you need to walk over sugar nodes that represent some
2568	/// kind of type adjustment from a type that was written as a \<specific type>
2569	/// to another type that is still canonically a \<specific type>.
2570	template <typename T> const T *getAsAdjusted() const;
2571
2572	/// A variant of getAs<> for array types which silently discards
2573	/// qualifiers from the outermost type.
2574	const ArrayType *getAsArrayTypeUnsafe() const;
2575
2576	/// Member-template castAs<specific type>. Look through sugar for
2577	/// the underlying instance of \<specific type>.
2578	///
2579	/// This method has the same relationship to getAs<T> as cast<T> has
2580	/// to dyn_cast<T>; which is to say, the underlying type *must*
2581	/// have the intended type, and this method will never return null.
2582	template <typename T> const T *castAs() const;
2583
2584	/// A variant of castAs<> for array type which silently discards
2585	/// qualifiers from the outermost type.
2586	const ArrayType *castAsArrayTypeUnsafe() const;
2587
2588	/// Determine whether this type had the specified attribute applied to it
2589	/// (looking through top-level type sugar).
2590	bool hasAttr(attr::Kind AK) const;
2591
2592	/// Get the base element type of this type, potentially discarding type
2593	/// qualifiers. This should never be used when type qualifiers
2594	/// are meaningful.
2595	const Type *getBaseElementTypeUnsafe() const;
2596
2597	/// If this is an array type, return the element type of the array,
2598	/// potentially with type qualifiers missing.
2599	/// This should never be used when type qualifiers are meaningful.
2600	const Type *getArrayElementTypeNoTypeQual() const;
2601
2602	/// If this is a pointer type, return the pointee type.
2603	/// If this is an array type, return the array element type.
2604	/// This should never be used when type qualifiers are meaningful.
2605	const Type *getPointeeOrArrayElementType() const;
2606
2607	/// If this is a pointer, ObjC object pointer, or block
2608	/// pointer, this returns the respective pointee.
2609	QualType getPointeeType() const;
2610
2611	/// Return the specified type with any "sugar" removed from the type,
2612	/// removing any typedefs, typeofs, etc., as well as any qualifiers.
2613	const Type *getUnqualifiedDesugaredType() const;
2614
2615	/// Return true if this is an integer type that is
2616	/// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
2617	/// or an enum decl which has a signed representation.
2618	bool isSignedIntegerType() const;
2619
2620	/// Return true if this is an integer type that is
2621	/// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
2622	/// or an enum decl which has an unsigned representation.
2623	bool isUnsignedIntegerType() const;
2624
2625	/// Determines whether this is an integer type that is signed or an
2626	/// enumeration types whose underlying type is a signed integer type.
2627	bool isSignedIntegerOrEnumerationType() const;
2628
2629	/// Determines whether this is an integer type that is unsigned or an
2630	/// enumeration types whose underlying type is a unsigned integer type.
2631	bool isUnsignedIntegerOrEnumerationType() const;
2632
2633	/// Return true if this is a fixed point type according to
2634	/// ISO/IEC JTC1 SC22 WG14 N1169.
2635	bool isFixedPointType() const;
2636
2637	/// Return true if this is a fixed point or integer type.
2638	bool isFixedPointOrIntegerType() const;
2639
2640	/// Return true if this can be converted to (or from) a fixed point type.
2641	bool isConvertibleToFixedPointType() const;
2642
2643	/// Return true if this is a saturated fixed point type according to
2644	/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2645	bool isSaturatedFixedPointType() const;
2646
2647	/// Return true if this is a saturated fixed point type according to
2648	/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2649	bool isUnsaturatedFixedPointType() const;
2650
2651	/// Return true if this is a fixed point type that is signed according
2652	/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2653	bool isSignedFixedPointType() const;
2654
2655	/// Return true if this is a fixed point type that is unsigned according
2656	/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2657	bool isUnsignedFixedPointType() const;
2658
2659	/// Return true if this is not a variable sized type,
2660	/// according to the rules of C99 6.7.5p3. It is not legal to call this on
2661	/// incomplete types.
2662	bool isConstantSizeType() const;
2663
2664	/// Returns true if this type can be represented by some
2665	/// set of type specifiers.
2666	bool isSpecifierType() const;
2667
2668	/// Determine the linkage of this type.
2669	Linkage getLinkage() const;
2670
2671	/// Determine the visibility of this type.
2672	Visibility getVisibility() const {
2673	return getLinkageAndVisibility().getVisibility();
2674	}
2675
2676	/// Return true if the visibility was explicitly set is the code.
2677	bool isVisibilityExplicit() const {
2678	return getLinkageAndVisibility().isVisibilityExplicit();
2679	}
2680
2681	/// Determine the linkage and visibility of this type.
2682	LinkageInfo getLinkageAndVisibility() const;
2683
2684	/// True if the computed linkage is valid. Used for consistency
2685	/// checking. Should always return true.
2686	bool isLinkageValid() const;
2687
2688	/// Determine the nullability of the given type.
2689	///
2690	/// Note that nullability is only captured as sugar within the type
2691	/// system, not as part of the canonical type, so nullability will
2692	/// be lost by canonicalization and desugaring.
2693	std::optional<NullabilityKind> getNullability() const;
2694
2695	/// Determine whether the given type can have a nullability
2696	/// specifier applied to it, i.e., if it is any kind of pointer type.
2697	///
2698	/// \param ResultIfUnknown The value to return if we don't yet know whether
2699	/// this type can have nullability because it is dependent.
2700	bool canHaveNullability(bool ResultIfUnknown = true) const;
2701
2702	/// Retrieve the set of substitutions required when accessing a member
2703	/// of the Objective-C receiver type that is declared in the given context.
2704	///
2705	/// \c *this is the type of the object we're operating on, e.g., the
2706	/// receiver for a message send or the base of a property access, and is
2707	/// expected to be of some object or object pointer type.
2708	///
2709	/// \param dc The declaration context for which we are building up a
2710	/// substitution mapping, which should be an Objective-C class, extension,
2711	/// category, or method within.
2712	///
2713	/// \returns an array of type arguments that can be substituted for
2714	/// the type parameters of the given declaration context in any type described
2715	/// within that context, or an empty optional to indicate that no
2716	/// substitution is required.
2717	std::optional<ArrayRef<QualType>>
2718	getObjCSubstitutions(const DeclContext *dc) const;
2719
2720	/// Determines if this is an ObjC interface type that may accept type
2721	/// parameters.
2722	bool acceptsObjCTypeParams() const;
2723
2724	const char *getTypeClassName() const;
2725
2726	QualType getCanonicalTypeInternal() const {
2727	return CanonicalType;
2728	}
2729
2730	CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
2731	void dump() const;
2732	void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
2733	};
2734
2735	/// This will check for a TypedefType by removing any existing sugar
2736	/// until it reaches a TypedefType or a non-sugared type.
2737	template <> const TypedefType *Type::getAs() const;
2738	template <> const UsingType *Type::getAs() const;
2739
2740	/// This will check for a TemplateSpecializationType by removing any
2741	/// existing sugar until it reaches a TemplateSpecializationType or a
2742	/// non-sugared type.
2743	template <> const TemplateSpecializationType *Type::getAs() const;
2744
2745	/// This will check for an AttributedType by removing any existing sugar
2746	/// until it reaches an AttributedType or a non-sugared type.
2747	template <> const AttributedType *Type::getAs() const;
2748
2749	/// This will check for a BoundsAttributedType by removing any existing
2750	/// sugar until it reaches an BoundsAttributedType or a non-sugared type.
2751	template <> const BoundsAttributedType *Type::getAs() const;
2752
2753	/// This will check for a CountAttributedType by removing any existing
2754	/// sugar until it reaches an CountAttributedType or a non-sugared type.
2755	template <> const CountAttributedType *Type::getAs() const;
2756
2757	// We can do canonical leaf types faster, because we don't have to
2758	// worry about preserving child type decoration.
2759	#define TYPE(Class, Base)
2760	#define LEAF_TYPE(Class) \
2761	template <> inline const Class##Type *Type::getAs() const { \
2762	return dyn_cast<Class##Type>(CanonicalType); \
2763	} \
2764	template <> inline const Class##Type *Type::castAs() const { \
2765	return cast<Class##Type>(CanonicalType); \
2766	}
2767	#include "clang/AST/TypeNodes.inc"
2768
2769	/// This class is used for builtin types like 'int'. Builtin
2770	/// types are always canonical and have a literal name field.
2771	class BuiltinType : public Type {
2772	public:
2773	enum Kind {
2774	// OpenCL image types
2775	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2776	#include "clang/Basic/OpenCLImageTypes.def"
2777	// OpenCL extension types
2778	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) Id,
2779	#include "clang/Basic/OpenCLExtensionTypes.def"
2780	// SVE Types
2781	#define SVE_TYPE(Name, Id, SingletonId) Id,
2782	#include "clang/Basic/AArch64SVEACLETypes.def"
2783	// PPC MMA Types
2784	#define PPC_VECTOR_TYPE(Name, Id, Size) Id,
2785	#include "clang/Basic/PPCTypes.def"
2786	// RVV Types
2787	#define RVV_TYPE(Name, Id, SingletonId) Id,
2788	#include "clang/Basic/RISCVVTypes.def"
2789	// WebAssembly reference types
2790	#define WASM_TYPE(Name, Id, SingletonId) Id,
2791	#include "clang/Basic/WebAssemblyReferenceTypes.def"
2792	// All other builtin types
2793	#define BUILTIN_TYPE(Id, SingletonId) Id,
2794	#define LAST_BUILTIN_TYPE(Id) LastKind = Id
2795	#include "clang/AST/BuiltinTypes.def"
2796	};
2797
2798	private:
2799	friend class ASTContext; // ASTContext creates these.
2800
2801	BuiltinType(Kind K)
2802	: Type(Builtin, QualType(),
2803	K == Dependent ? TypeDependence::DependentInstantiation
2804	: TypeDependence::None) {
2805	static_assert(Kind::LastKind <
2806	(1 << BuiltinTypeBitfields::NumOfBuiltinTypeBits) &&
2807	"Defined builtin type exceeds the allocated space for serial "
2808	"numbering");
2809	BuiltinTypeBits.Kind = K;
2810	}
2811
2812	public:
2813	Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
2814	StringRef getName(const PrintingPolicy &Policy) const;
2815
2816	const char *getNameAsCString(const PrintingPolicy &Policy) const {
2817	// The StringRef is null-terminated.
2818	StringRef str = getName(Policy);
2819	assert(!str.empty() && str.data()[str.size()] == '\0');
2820	return str.data();
2821	}
2822
2823	bool isSugared() const { return false; }
2824	QualType desugar() const { return QualType(this, 0); }
2825
2826	bool isInteger() const {
2827	return getKind() >= Bool && getKind() <= Int128;
2828	}
2829
2830	bool isSignedInteger() const {
2831	return getKind() >= Char_S && getKind() <= Int128;
2832	}
2833
2834	bool isUnsignedInteger() const {
2835	return getKind() >= Bool && getKind() <= UInt128;
2836	}
2837
2838	bool isFloatingPoint() const {
2839	return getKind() >= Half && getKind() <= Ibm128;
2840	}
2841
2842	bool isSVEBool() const { return getKind() == Kind::SveBool; }
2843
2844	bool isSVECount() const { return getKind() == Kind::SveCount; }
2845
2846	/// Determines whether the given kind corresponds to a placeholder type.
2847	static bool isPlaceholderTypeKind(Kind K) {
2848	return K >= Overload;
2849	}
2850
2851	/// Determines whether this type is a placeholder type, i.e. a type
2852	/// which cannot appear in arbitrary positions in a fully-formed
2853	/// expression.
2854	bool isPlaceholderType() const {
2855	return isPlaceholderTypeKind(K: getKind());
2856	}
2857
2858	/// Determines whether this type is a placeholder type other than
2859	/// Overload. Most placeholder types require only syntactic
2860	/// information about their context in order to be resolved (e.g.
2861	/// whether it is a call expression), which means they can (and
2862	/// should) be resolved in an earlier "phase" of analysis.
2863	/// Overload expressions sometimes pick up further information
2864	/// from their context, like whether the context expects a
2865	/// specific function-pointer type, and so frequently need
2866	/// special treatment.
2867	bool isNonOverloadPlaceholderType() const {
2868	return getKind() > Overload;
2869	}
2870
2871	static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2872	};
2873
2874	/// Complex values, per C99 6.2.5p11. This supports the C99 complex
2875	/// types (_Complex float etc) as well as the GCC integer complex extensions.
2876	class ComplexType : public Type, public llvm::FoldingSetNode {
2877	friend class ASTContext; // ASTContext creates these.
2878
2879	QualType ElementType;
2880
2881	ComplexType(QualType Element, QualType CanonicalPtr)
2882	: Type(Complex, CanonicalPtr, Element->getDependence()),
2883	ElementType(Element) {}
2884
2885	public:
2886	QualType getElementType() const { return ElementType; }
2887
2888	bool isSugared() const { return false; }
2889	QualType desugar() const { return QualType(this, 0); }
2890
2891	void Profile(llvm::FoldingSetNodeID &ID) {
2892	Profile(ID, Element: getElementType());
2893	}
2894
2895	static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
2896	ID.AddPointer(Ptr: Element.getAsOpaquePtr());
2897	}
2898
2899	static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2900	};
2901
2902	/// Sugar for parentheses used when specifying types.
2903	class ParenType : public Type, public llvm::FoldingSetNode {
2904	friend class ASTContext; // ASTContext creates these.
2905
2906	QualType Inner;
2907
2908	ParenType(QualType InnerType, QualType CanonType)
2909	: Type(Paren, CanonType, InnerType->getDependence()), Inner(InnerType) {}
2910
2911	public:
2912	QualType getInnerType() const { return Inner; }
2913
2914	bool isSugared() const { return true; }
2915	QualType desugar() const { return getInnerType(); }
2916
2917	void Profile(llvm::FoldingSetNodeID &ID) {
2918	Profile(ID, Inner: getInnerType());
2919	}
2920
2921	static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
2922	Inner.Profile(ID);
2923	}
2924
2925	static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2926	};
2927
2928	/// PointerType - C99 6.7.5.1 - Pointer Declarators.
2929	class PointerType : public Type, public llvm::FoldingSetNode {
2930	friend class ASTContext; // ASTContext creates these.
2931
2932	QualType PointeeType;
2933
2934	PointerType(QualType Pointee, QualType CanonicalPtr)
2935	: Type(Pointer, CanonicalPtr, Pointee->getDependence()),
2936	PointeeType(Pointee) {}
2937
2938	public:
2939	QualType getPointeeType() const { return PointeeType; }
2940
2941	bool isSugared() const { return false; }
2942	QualType desugar() const { return QualType(this, 0); }
2943
2944	void Profile(llvm::FoldingSetNodeID &ID) {
2945	Profile(ID, Pointee: getPointeeType());
2946	}
2947
2948	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2949	ID.AddPointer(Ptr: Pointee.getAsOpaquePtr());
2950	}
2951
2952	static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2953	};
2954
2955	/// [BoundsSafety] Represents information of declarations referenced by the
2956	/// arguments of the `counted_by` attribute and the likes.
2957	class TypeCoupledDeclRefInfo {
2958	public:
2959	using BaseTy = llvm::PointerIntPair<ValueDecl *, 1, unsigned>;
2960
2961	private:
2962	enum {
2963	DerefShift = 0,
2964	DerefMask = 1,
2965	};
2966	BaseTy Data;
2967
2968	public:
2969	/// \p D is to a declaration referenced by the argument of attribute. \p Deref
2970	/// indicates whether \p D is referenced as a dereferenced form, e.g., \p
2971	/// Deref is true for `*n` in `int *__counted_by(*n)`.
2972	TypeCoupledDeclRefInfo(ValueDecl *D = nullptr, bool Deref = false);
2973
2974	bool isDeref() const;
2975	ValueDecl *getDecl() const;
2976	unsigned getInt() const;
2977	void *getOpaqueValue() const;
2978	bool operator==(const TypeCoupledDeclRefInfo &Other) const;
2979	void setFromOpaqueValue(void *V);
2980	};
2981
2982	/// [BoundsSafety] Represents a parent type class for CountAttributedType and
2983	/// similar sugar types that will be introduced to represent a type with a
2984	/// bounds attribute.
2985	///
2986	/// Provides a common interface to navigate declarations referred to by the
2987	/// bounds expression.
2988
2989	class BoundsAttributedType : public Type, public llvm::FoldingSetNode {
2990	QualType WrappedTy;
2991
2992	protected:
2993	ArrayRef<TypeCoupledDeclRefInfo> Decls; // stored in trailing objects
2994
2995	BoundsAttributedType(TypeClass TC, QualType Wrapped, QualType Canon);
2996
2997	public:
2998	bool isSugared() const { return true; }
2999	QualType desugar() const { return WrappedTy; }
3000
3001	using decl_iterator = const TypeCoupledDeclRefInfo *;
3002	using decl_range = llvm::iterator_range<decl_iterator>;
3003
3004	decl_iterator dependent_decl_begin() const { return Decls.begin(); }
3005	decl_iterator dependent_decl_end() const { return Decls.end(); }
3006
3007	unsigned getNumCoupledDecls() const { return Decls.size(); }
3008
3009	decl_range dependent_decls() const {
3010	return decl_range(dependent_decl_begin(), dependent_decl_end());
3011	}
3012
3013	ArrayRef<TypeCoupledDeclRefInfo> getCoupledDecls() const {
3014	return {dependent_decl_begin(), dependent_decl_end()};
3015	}
3016
3017	bool referencesFieldDecls() const;
3018
3019	static bool classof(const Type *T) {
3020	// Currently, only `class CountAttributedType` inherits
3021	// `BoundsAttributedType` but the subclass will grow as we add more bounds
3022	// annotations.
3023	switch (T->getTypeClass()) {
3024	case CountAttributed:
3025	return true;
3026	default:
3027	return false;
3028	}
3029	}
3030	};
3031
3032	/// Represents a sugar type with `__counted_by` or `__sized_by` annotations,
3033	/// including their `_or_null` variants.
3034	class CountAttributedType final
3035	: public BoundsAttributedType,
3036	public llvm::TrailingObjects<CountAttributedType,
3037	TypeCoupledDeclRefInfo> {
3038	friend class ASTContext;
3039
3040	Expr *CountExpr;
3041	/// \p CountExpr represents the argument of __counted_by or the likes. \p
3042	/// CountInBytes indicates that \p CountExpr is a byte count (i.e.,
3043	/// __sized_by(_or_null)) \p OrNull means it's an or_null variant (i.e.,
3044	/// __counted_by_or_null or __sized_by_or_null) \p CoupledDecls contains the
3045	/// list of declarations referenced by \p CountExpr, which the type depends on
3046	/// for the bounds information.
3047	CountAttributedType(QualType Wrapped, QualType Canon, Expr *CountExpr,
3048	bool CountInBytes, bool OrNull,
3049	ArrayRef<TypeCoupledDeclRefInfo> CoupledDecls);
3050
3051	unsigned numTrailingObjects(OverloadToken<TypeCoupledDeclRefInfo>) const {
3052	return CountAttributedTypeBits.NumCoupledDecls;
3053	}
3054
3055	public:
3056	enum DynamicCountPointerKind {
3057	CountedBy = 0,
3058	SizedBy,
3059	CountedByOrNull,
3060	SizedByOrNull,
3061	};
3062
3063	Expr *getCountExpr() const { return CountExpr; }
3064	bool isCountInBytes() const { return CountAttributedTypeBits.CountInBytes; }
3065	bool isOrNull() const { return CountAttributedTypeBits.OrNull; }
3066
3067	DynamicCountPointerKind getKind() const {
3068	if (isOrNull())
3069	return isCountInBytes() ? SizedByOrNull : CountedByOrNull;
3070	return isCountInBytes() ? SizedBy : CountedBy;
3071	}
3072
3073	void Profile(llvm::FoldingSetNodeID &ID) {
3074	Profile(ID, desugar(), CountExpr, isCountInBytes(), isOrNull());
3075	}
3076
3077	static void Profile(llvm::FoldingSetNodeID &ID, QualType WrappedTy,
3078	Expr *CountExpr, bool CountInBytes, bool Nullable);
3079
3080	static bool classof(const Type *T) {
3081	return T->getTypeClass() == CountAttributed;
3082	}
3083	};
3084
3085	/// Represents a type which was implicitly adjusted by the semantic
3086	/// engine for arbitrary reasons. For example, array and function types can
3087	/// decay, and function types can have their calling conventions adjusted.
3088	class AdjustedType : public Type, public llvm::FoldingSetNode {
3089	QualType OriginalTy;
3090	QualType AdjustedTy;
3091
3092	protected:
3093	friend class ASTContext; // ASTContext creates these.
3094
3095	AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
3096	QualType CanonicalPtr)
3097	: Type(TC, CanonicalPtr, OriginalTy->getDependence()),
3098	OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
3099
3100	public:
3101	QualType getOriginalType() const { return OriginalTy; }
3102	QualType getAdjustedType() const { return AdjustedTy; }
3103
3104	bool isSugared() const { return true; }
3105	QualType desugar() const { return AdjustedTy; }
3106
3107	void Profile(llvm::FoldingSetNodeID &ID) {
3108	Profile(ID, OriginalTy, AdjustedTy);
3109	}
3110
3111	static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
3112	ID.AddPointer(Ptr: Orig.getAsOpaquePtr());
3113	ID.AddPointer(Ptr: New.getAsOpaquePtr());
3114	}
3115
3116	static bool classof(const Type *T) {
3117	return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
3118	}
3119	};
3120
3121	/// Represents a pointer type decayed from an array or function type.
3122	class DecayedType : public AdjustedType {
3123	friend class ASTContext; // ASTContext creates these.
3124
3125	inline
3126	DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);
3127
3128	public:
3129	QualType getDecayedType() const { return getAdjustedType(); }
3130
3131	inline QualType getPointeeType() const;
3132
3133	static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
3134	};
3135
3136	/// Pointer to a block type.
3137	/// This type is to represent types syntactically represented as
3138	/// "void (^)(int)", etc. Pointee is required to always be a function type.
3139	class BlockPointerType : public Type, public llvm::FoldingSetNode {
3140	friend class ASTContext; // ASTContext creates these.
3141
3142	// Block is some kind of pointer type
3143	QualType PointeeType;
3144
3145	BlockPointerType(QualType Pointee, QualType CanonicalCls)
3146	: Type(BlockPointer, CanonicalCls, Pointee->getDependence()),
3147	PointeeType(Pointee) {}
3148
3149	public:
3150	// Get the pointee type. Pointee is required to always be a function type.
3151	QualType getPointeeType() const { return PointeeType; }
3152
3153	bool isSugared() const { return false; }
3154	QualType desugar() const { return QualType(this, 0); }
3155
3156	void Profile(llvm::FoldingSetNodeID &ID) {
3157	Profile(ID, Pointee: getPointeeType());
3158	}
3159
3160	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
3161	ID.AddPointer(Ptr: Pointee.getAsOpaquePtr());
3162	}
3163
3164	static bool classof(const Type *T) {
3165	return T->getTypeClass() == BlockPointer;
3166	}
3167	};
3168
3169	/// Base for LValueReferenceType and RValueReferenceType
3170	class ReferenceType : public Type, public llvm::FoldingSetNode {
3171	QualType PointeeType;
3172
3173	protected:
3174	ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
3175	bool SpelledAsLValue)
3176	: Type(tc, CanonicalRef, Referencee->getDependence()),
3177	PointeeType(Referencee) {
3178	ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
3179	ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
3180	}
3181
3182	public:
3183	bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
3184	bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }
3185
3186	QualType getPointeeTypeAsWritten() const { return PointeeType; }
3187
3188	QualType getPointeeType() const {
3189	// FIXME: this might strip inner qualifiers; okay?
3190	const ReferenceType *T = this;
3191	while (T->isInnerRef())
3192	T = T->PointeeType->castAs<ReferenceType>();
3193	return T->PointeeType;
3194	}
3195
3196	void Profile(llvm::FoldingSetNodeID &ID) {
3197	Profile(ID, PointeeType, isSpelledAsLValue());
3198	}
3199
3200	static void Profile(llvm::FoldingSetNodeID &ID,
3201	QualType Referencee,
3202	bool SpelledAsLValue) {
3203	ID.AddPointer(Ptr: Referencee.getAsOpaquePtr());
3204	ID.AddBoolean(B: SpelledAsLValue);
3205	}
3206
3207	static bool classof(const Type *T) {
3208	return T->getTypeClass() == LValueReference ||
3209	T->getTypeClass() == RValueReference;
3210	}
3211	};
3212
3213	/// An lvalue reference type, per C++11 [dcl.ref].
3214	class LValueReferenceType : public ReferenceType {
3215	friend class ASTContext; // ASTContext creates these
3216
3217	LValueReferenceType(QualType Referencee, QualType CanonicalRef,
3218	bool SpelledAsLValue)
3219	: ReferenceType(LValueReference, Referencee, CanonicalRef,
3220	SpelledAsLValue) {}
3221
3222	public:
3223	bool isSugared() const { return false; }
3224	QualType desugar() const { return QualType(this, 0); }
3225
3226	static bool classof(const Type *T) {
3227	return T->getTypeClass() == LValueReference;
3228	}
3229	};
3230
3231	/// An rvalue reference type, per C++11 [dcl.ref].
3232	class RValueReferenceType : public ReferenceType {
3233	friend class ASTContext; // ASTContext creates these
3234
3235	RValueReferenceType(QualType Referencee, QualType CanonicalRef)
3236	: ReferenceType(RValueReference, Referencee, CanonicalRef, false) {}
3237
3238	public:
3239	bool isSugared() const { return false; }
3240	QualType desugar() const { return QualType(this, 0); }
3241
3242	static bool classof(const Type *T) {
3243	return T->getTypeClass() == RValueReference;
3244	}
3245	};
3246
3247	/// A pointer to member type per C++ 8.3.3 - Pointers to members.
3248	///
3249	/// This includes both pointers to data members and pointer to member functions.
3250	class MemberPointerType : public Type, public llvm::FoldingSetNode {
3251	friend class ASTContext; // ASTContext creates these.
3252
3253	QualType PointeeType;
3254
3255	/// The class of which the pointee is a member. Must ultimately be a
3256	/// RecordType, but could be a typedef or a template parameter too.
3257	const Type *Class;
3258
3259	MemberPointerType(QualType Pointee, const Type *Cls, QualType CanonicalPtr)
3260	: Type(MemberPointer, CanonicalPtr,
3261	(Cls->getDependence() & ~TypeDependence::VariablyModified) |
3262	Pointee->getDependence()),
3263	PointeeType(Pointee), Class(Cls) {}
3264
3265	public:
3266	QualType getPointeeType() const { return PointeeType; }
3267
3268	/// Returns true if the member type (i.e. the pointee type) is a
3269	/// function type rather than a data-member type.
3270	bool isMemberFunctionPointer() const {
3271	return PointeeType->isFunctionProtoType();
3272	}
3273
3274	/// Returns true if the member type (i.e. the pointee type) is a
3275	/// data type rather than a function type.
3276	bool isMemberDataPointer() const {
3277	return !PointeeType->isFunctionProtoType();
3278	}
3279
3280	const Type *getClass() const { return Class; }
3281	CXXRecordDecl *getMostRecentCXXRecordDecl() const;
3282
3283	bool isSugared() const { return false; }
3284	QualType desugar() const { return QualType(this, 0); }
3285
3286	void Profile(llvm::FoldingSetNodeID &ID) {
3287	Profile(ID, Pointee: getPointeeType(), Class: getClass());
3288	}
3289
3290	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee,
3291	const Type *Class) {
3292	ID.AddPointer(Ptr: Pointee.getAsOpaquePtr());
3293	ID.AddPointer(Ptr: Class);
3294	}
3295
3296	static bool classof(const Type *T) {
3297	return T->getTypeClass() == MemberPointer;
3298	}
3299	};
3300
3301	/// Capture whether this is a normal array (e.g. int X[4])
3302	/// an array with a static size (e.g. int X[static 4]), or an array
3303	/// with a star size (e.g. int X[*]).
3304	/// 'static' is only allowed on function parameters.
3305	enum class ArraySizeModifier { Normal, Static, Star };
3306
3307	/// Represents an array type, per C99 6.7.5.2 - Array Declarators.
3308	class ArrayType : public Type, public llvm::FoldingSetNode {
3309	private:
3310	/// The element type of the array.
3311	QualType ElementType;
3312
3313	protected:
3314	friend class ASTContext; // ASTContext creates these.
3315
3316	ArrayType(TypeClass tc, QualType et, QualType can, ArraySizeModifier sm,
3317	unsigned tq, const Expr *sz = nullptr);
3318
3319	public:
3320	QualType getElementType() const { return ElementType; }
3321
3322	ArraySizeModifier getSizeModifier() const {
3323	return ArraySizeModifier(ArrayTypeBits.SizeModifier);
3324	}
3325
3326	Qualifiers getIndexTypeQualifiers() const {
3327	return Qualifiers::fromCVRMask(CVR: getIndexTypeCVRQualifiers());
3328	}
3329
3330	unsigned getIndexTypeCVRQualifiers() const {
3331	return ArrayTypeBits.IndexTypeQuals;
3332	}
3333
3334	static bool classof(const Type *T) {
3335	return T->getTypeClass() == ConstantArray ||
3336	T->getTypeClass() == VariableArray ||
3337	T->getTypeClass() == IncompleteArray ||
3338	T->getTypeClass() == DependentSizedArray ||
3339	T->getTypeClass() == ArrayParameter;
3340	}
3341	};
3342
3343	/// Represents the canonical version of C arrays with a specified constant size.
3344	/// For example, the canonical type for 'int A[4 + 4*100]' is a
3345	/// ConstantArrayType where the element type is 'int' and the size is 404.
3346	class ConstantArrayType : public ArrayType {
3347	friend class ASTContext; // ASTContext creates these.
3348
3349	struct ExternalSize {
3350	ExternalSize(const llvm::APInt &Sz, const Expr *SE)
3351	: Size(Sz), SizeExpr(SE) {}
3352	llvm::APInt Size; // Allows us to unique the type.
3353	const Expr *SizeExpr;
3354	};
3355
3356	union {
3357	uint64_t Size;
3358	ExternalSize *SizePtr;
3359	};
3360
3361	ConstantArrayType(QualType Et, QualType Can, uint64_t Width, uint64_t Sz,
3362	ArraySizeModifier SM, unsigned TQ)
3363	: ArrayType(ConstantArray, Et, Can, SM, TQ, nullptr), Size(Sz) {
3364	ConstantArrayTypeBits.HasExternalSize = false;
3365	ConstantArrayTypeBits.SizeWidth = Width / 8;
3366	// The in-structure size stores the size in bytes rather than bits so we
3367	// drop the three least significant bits since they're always zero anyways.
3368	assert(Width < 0xFF && "Type width in bits must be less than 8 bits");
3369	}
3370
3371	ConstantArrayType(QualType Et, QualType Can, ExternalSize *SzPtr,
3372	ArraySizeModifier SM, unsigned TQ)
3373	: ArrayType(ConstantArray, Et, Can, SM, TQ, SzPtr->SizeExpr),
3374	SizePtr(SzPtr) {
3375	ConstantArrayTypeBits.HasExternalSize = true;
3376	ConstantArrayTypeBits.SizeWidth = 0;
3377
3378	assert((SzPtr->SizeExpr == nullptr || !Can.isNull()) &&
3379	"canonical constant array should not have size expression");
3380	}
3381
3382	static ConstantArrayType *Create(const ASTContext &Ctx, QualType ET,
3383	QualType Can, const llvm::APInt &Sz,
3384	const Expr *SzExpr, ArraySizeModifier SzMod,
3385	unsigned Qual);
3386
3387	protected:
3388	ConstantArrayType(TypeClass Tc, const ConstantArrayType *ATy, QualType Can)
3389	: ArrayType(Tc, ATy->getElementType(), Can, ATy->getSizeModifier(),
3390	ATy->getIndexTypeQualifiers().getAsOpaqueValue(), nullptr) {
3391	ConstantArrayTypeBits.HasExternalSize =
3392	ATy->ConstantArrayTypeBits.HasExternalSize;
3393	if (!ConstantArrayTypeBits.HasExternalSize) {
3394	ConstantArrayTypeBits.SizeWidth = ATy->ConstantArrayTypeBits.SizeWidth;
3395	Size = ATy->Size;
3396	} else
3397	SizePtr = ATy->SizePtr;
3398	}
3399
3400	public:
3401	/// Return the constant array size as an APInt.
3402	llvm::APInt getSize() const {
3403	return ConstantArrayTypeBits.HasExternalSize
3404	? SizePtr->Size
3405	: llvm::APInt(ConstantArrayTypeBits.SizeWidth * 8, Size);
3406	}
3407
3408	/// Return the bit width of the size type.
3409	unsigned getSizeBitWidth() const {
3410	return ConstantArrayTypeBits.HasExternalSize
3411	? SizePtr->Size.getBitWidth()
3412	: static_cast<unsigned>(ConstantArrayTypeBits.SizeWidth * 8);
3413	}
3414
3415	/// Return true if the size is zero.
3416	bool isZeroSize() const {
3417	return ConstantArrayTypeBits.HasExternalSize ? SizePtr->Size.isZero()
3418	: 0 == Size;
3419	}
3420
3421	/// Return the size zero-extended as a uint64_t.
3422	uint64_t getZExtSize() const {
3423	return ConstantArrayTypeBits.HasExternalSize ? SizePtr->Size.getZExtValue()
3424	: Size;
3425	}
3426
3427	/// Return the size sign-extended as a uint64_t.
3428	int64_t getSExtSize() const {
3429	return ConstantArrayTypeBits.HasExternalSize ? SizePtr->Size.getSExtValue()
3430	: static_cast<int64_t>(Size);
3431	}
3432
3433	/// Return the size zero-extended to uint64_t or UINT64_MAX if the value is
3434	/// larger than UINT64_MAX.
3435	uint64_t getLimitedSize() const {
3436	return ConstantArrayTypeBits.HasExternalSize
3437	? SizePtr->Size.getLimitedValue()
3438	: Size;
3439	}
3440
3441	/// Return a pointer to the size expression.
3442	const Expr *getSizeExpr() const {
3443	return ConstantArrayTypeBits.HasExternalSize ? SizePtr->SizeExpr : nullptr;
3444	}
3445
3446	bool isSugared() const { return false; }
3447	QualType desugar() const { return QualType(this, 0); }
3448
3449	/// Determine the number of bits required to address a member of
3450	// an array with the given element type and number of elements.
3451	static unsigned getNumAddressingBits(const ASTContext &Context,
3452	QualType ElementType,
3453	const llvm::APInt &NumElements);
3454
3455	unsigned getNumAddressingBits(const ASTContext &Context) const;
3456
3457	/// Determine the maximum number of active bits that an array's size
3458	/// can require, which limits the maximum size of the array.
3459	static unsigned getMaxSizeBits(const ASTContext &Context);
3460
3461	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx) {
3462	Profile(ID, Ctx, getElementType(), getZExtSize(), getSizeExpr(),
3463	getSizeModifier(), getIndexTypeCVRQualifiers());
3464	}
3465
3466	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx,
3467	QualType ET, uint64_t ArraySize, const Expr *SizeExpr,
3468	ArraySizeModifier SizeMod, unsigned TypeQuals);
3469
3470	static bool classof(const Type *T) {
3471	return T->getTypeClass() == ConstantArray ||
3472	T->getTypeClass() == ArrayParameter;
3473	}
3474	};
3475
3476	/// Represents a constant array type that does not decay to a pointer when used
3477	/// as a function parameter.
3478	class ArrayParameterType : public ConstantArrayType {
3479	friend class ASTContext; // ASTContext creates these.
3480
3481	ArrayParameterType(const ConstantArrayType *ATy, QualType CanTy)
3482	: ConstantArrayType(ArrayParameter, ATy, CanTy) {}
3483
3484	public:
3485	static bool classof(const Type *T) {
3486	return T->getTypeClass() == ArrayParameter;
3487	}
3488	};
3489
3490	/// Represents a C array with an unspecified size. For example 'int A[]' has
3491	/// an IncompleteArrayType where the element type is 'int' and the size is
3492	/// unspecified.
3493	class IncompleteArrayType : public ArrayType {
3494	friend class ASTContext; // ASTContext creates these.
3495
3496	IncompleteArrayType(QualType et, QualType can,
3497	ArraySizeModifier sm, unsigned tq)
3498	: ArrayType(IncompleteArray, et, can, sm, tq) {}
3499
3500	public:
3501	friend class StmtIteratorBase;
3502
3503	bool isSugared() const { return false; }
3504	QualType desugar() const { return QualType(this, 0); }
3505
3506	static bool classof(const Type *T) {
3507	return T->getTypeClass() == IncompleteArray;
3508	}
3509
3510	void Profile(llvm::FoldingSetNodeID &ID) {
3511	Profile(ID, getElementType(), getSizeModifier(),
3512	getIndexTypeCVRQualifiers());
3513	}
3514
3515	static void Profile(llvm::FoldingSetNodeID &ID, QualType ET,
3516	ArraySizeModifier SizeMod, unsigned TypeQuals) {
3517	ID.AddPointer(Ptr: ET.getAsOpaquePtr());
3518	ID.AddInteger(llvm::to_underlying(SizeMod));
3519	ID.AddInteger(I: TypeQuals);
3520	}
3521	};
3522
3523	/// Represents a C array with a specified size that is not an
3524	/// integer-constant-expression. For example, 'int s[x+foo()]'.
3525	/// Since the size expression is an arbitrary expression, we store it as such.
3526	///
3527	/// Note: VariableArrayType's aren't uniqued (since the expressions aren't) and
3528	/// should not be: two lexically equivalent variable array types could mean
3529	/// different things, for example, these variables do not have the same type
3530	/// dynamically:
3531	///
3532	/// void foo(int x) {
3533	/// int Y[x];
3534	/// ++x;
3535	/// int Z[x];
3536	/// }
3537	class VariableArrayType : public ArrayType {
3538	friend class ASTContext; // ASTContext creates these.
3539
3540	/// An assignment-expression. VLA's are only permitted within
3541	/// a function block.
3542	Stmt *SizeExpr;
3543
3544	/// The range spanned by the left and right array brackets.
3545	SourceRange Brackets;
3546
3547	VariableArrayType(QualType et, QualType can, Expr *e,
3548	ArraySizeModifier sm, unsigned tq,
3549	SourceRange brackets)
3550	: ArrayType(VariableArray, et, can, sm, tq, e),
3551	SizeExpr((Stmt*) e), Brackets(brackets) {}
3552
3553	public:
3554	friend class StmtIteratorBase;
3555
3556	Expr *getSizeExpr() const {
3557	// We use C-style casts instead of cast<> here because we do not wish
3558	// to have a dependency of Type.h on Stmt.h/Expr.h.
3559	return (Expr*) SizeExpr;
3560	}
3561
3562	SourceRange getBracketsRange() const { return Brackets; }
3563	SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
3564	SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
3565
3566	bool isSugared() const { return false; }
3567	QualType desugar() const { return QualType(this, 0); }
3568
3569	static bool classof(const Type *T) {
3570	return T->getTypeClass() == VariableArray;
3571	}
3572
3573	void Profile(llvm::FoldingSetNodeID &ID) {
3574	llvm_unreachable("Cannot unique VariableArrayTypes.");
3575	}
3576	};
3577
3578	/// Represents an array type in C++ whose size is a value-dependent expression.
3579	///
3580	/// For example:
3581	/// \code
3582	/// template<typename T, int Size>
3583	/// class array {
3584	/// T data[Size];
3585	/// };
3586	/// \endcode
3587	///
3588	/// For these types, we won't actually know what the array bound is
3589	/// until template instantiation occurs, at which point this will
3590	/// become either a ConstantArrayType or a VariableArrayType.
3591	class DependentSizedArrayType : public ArrayType {
3592	friend class ASTContext; // ASTContext creates these.
3593
3594	/// An assignment expression that will instantiate to the
3595	/// size of the array.
3596	///
3597	/// The expression itself might be null, in which case the array
3598	/// type will have its size deduced from an initializer.
3599	Stmt *SizeExpr;
3600
3601	/// The range spanned by the left and right array brackets.
3602	SourceRange Brackets;
3603
3604	DependentSizedArrayType(QualType et, QualType can, Expr *e,
3605	ArraySizeModifier sm, unsigned tq,
3606	SourceRange brackets);
3607
3608	public:
3609	friend class StmtIteratorBase;
3610
3611	Expr *getSizeExpr() const {
3612	// We use C-style casts instead of cast<> here because we do not wish
3613	// to have a dependency of Type.h on Stmt.h/Expr.h.
3614	return (Expr*) SizeExpr;
3615	}
3616
3617	SourceRange getBracketsRange() const { return Brackets; }
3618	SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
3619	SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
3620
3621	bool isSugared() const { return false; }
3622	QualType desugar() const { return QualType(this, 0); }
3623
3624	static bool classof(const Type *T) {
3625	return T->getTypeClass() == DependentSizedArray;
3626	}
3627
3628	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
3629	Profile(ID, Context, getElementType(),
3630	getSizeModifier(), getIndexTypeCVRQualifiers(), getSizeExpr());
3631	}
3632
3633	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3634	QualType ET, ArraySizeModifier SizeMod,
3635	unsigned TypeQuals, Expr *E);
3636	};
3637
3638	/// Represents an extended address space qualifier where the input address space
3639	/// value is dependent. Non-dependent address spaces are not represented with a
3640	/// special Type subclass; they are stored on an ExtQuals node as part of a QualType.
3641	///
3642	/// For example:
3643	/// \code
3644	/// template<typename T, int AddrSpace>
3645	/// class AddressSpace {
3646	/// typedef T __attribute__((address_space(AddrSpace))) type;
3647	/// }
3648	/// \endcode
3649	class DependentAddressSpaceType : public Type, public llvm::FoldingSetNode {
3650	friend class ASTContext;
3651
3652	Expr *AddrSpaceExpr;
3653	QualType PointeeType;
3654	SourceLocation loc;
3655
3656	DependentAddressSpaceType(QualType PointeeType, QualType can,
3657	Expr *AddrSpaceExpr, SourceLocation loc);
3658
3659	public:
3660	Expr *getAddrSpaceExpr() const { return AddrSpaceExpr; }
3661	QualType getPointeeType() const { return PointeeType; }
3662	SourceLocation getAttributeLoc() const { return loc; }
3663
3664	bool isSugared() const { return false; }
3665	QualType desugar() const { return QualType(this, 0); }
3666
3667	static bool classof(const Type *T) {
3668	return T->getTypeClass() == DependentAddressSpace;
3669	}
3670
3671	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
3672	Profile(ID, Context, PointeeType: getPointeeType(), AddrSpaceExpr: getAddrSpaceExpr());
3673	}
3674
3675	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3676	QualType PointeeType, Expr *AddrSpaceExpr);
3677	};
3678
3679	/// Represents an extended vector type where either the type or size is
3680	/// dependent.
3681	///
3682	/// For example:
3683	/// \code
3684	/// template<typename T, int Size>
3685	/// class vector {
3686	/// typedef T __attribute__((ext_vector_type(Size))) type;
3687	/// }
3688	/// \endcode
3689	class DependentSizedExtVectorType : public Type, public llvm::FoldingSetNode {
3690	friend class ASTContext;
3691
3692	Expr *SizeExpr;
3693
3694	/// The element type of the array.
3695	QualType ElementType;
3696
3697	SourceLocation loc;
3698
3699	DependentSizedExtVectorType(QualType ElementType, QualType can,
3700	Expr *SizeExpr, SourceLocation loc);
3701
3702	public:
3703	Expr *getSizeExpr() const { return SizeExpr; }
3704	QualType getElementType() const { return ElementType; }
3705	SourceLocation getAttributeLoc() const { return loc; }
3706
3707	bool isSugared() const { return false; }
3708	QualType desugar() const { return QualType(this, 0); }
3709
3710	static bool classof(const Type *T) {
3711	return T->getTypeClass() == DependentSizedExtVector;
3712	}
3713
3714	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
3715	Profile(ID, Context, ElementType: getElementType(), SizeExpr: getSizeExpr());
3716	}
3717
3718	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3719	QualType ElementType, Expr *SizeExpr);
3720	};
3721
3722	enum class VectorKind {
3723	/// not a target-specific vector type
3724	Generic,
3725
3726	/// is AltiVec vector
3727	AltiVecVector,
3728
3729	/// is AltiVec 'vector Pixel'
3730	AltiVecPixel,
3731
3732	/// is AltiVec 'vector bool ...'
3733	AltiVecBool,
3734
3735	/// is ARM Neon vector
3736	Neon,
3737
3738	/// is ARM Neon polynomial vector
3739	NeonPoly,
3740
3741	/// is AArch64 SVE fixed-length data vector
3742	SveFixedLengthData,
3743
3744	/// is AArch64 SVE fixed-length predicate vector
3745	SveFixedLengthPredicate,
3746
3747	/// is RISC-V RVV fixed-length data vector
3748	RVVFixedLengthData,
3749
3750	/// is RISC-V RVV fixed-length mask vector
3751	RVVFixedLengthMask,
3752	};
3753
3754	/// Represents a GCC generic vector type. This type is created using
3755	/// __attribute__((vector_size(n)), where "n" specifies the vector size in
3756	/// bytes; or from an Altivec __vector or vector declaration.
3757	/// Since the constructor takes the number of vector elements, the
3758	/// client is responsible for converting the size into the number of elements.
3759	class VectorType : public Type, public llvm::FoldingSetNode {
3760	protected:
3761	friend class ASTContext; // ASTContext creates these.
3762
3763	/// The element type of the vector.
3764	QualType ElementType;
3765
3766	VectorType(QualType vecType, unsigned nElements, QualType canonType,
3767	VectorKind vecKind);
3768
3769	VectorType(TypeClass tc, QualType vecType, unsigned nElements,
3770	QualType canonType, VectorKind vecKind);
3771
3772	public:
3773	QualType getElementType() const { return ElementType; }
3774	unsigned getNumElements() const { return VectorTypeBits.NumElements; }
3775
3776	bool isSugared() const { return false; }
3777	QualType desugar() const { return QualType(this, 0); }
3778
3779	VectorKind getVectorKind() const {
3780	return VectorKind(VectorTypeBits.VecKind);
3781	}
3782
3783	void Profile(llvm::FoldingSetNodeID &ID) {
3784	Profile(ID, getElementType(), getNumElements(),
3785	getTypeClass(), getVectorKind());
3786	}
3787
3788	static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
3789	unsigned NumElements, TypeClass TypeClass,
3790	VectorKind VecKind) {
3791	ID.AddPointer(Ptr: ElementType.getAsOpaquePtr());
3792	ID.AddInteger(I: NumElements);
3793	ID.AddInteger(I: TypeClass);
3794	ID.AddInteger(llvm::to_underlying(VecKind));
3795	}
3796
3797	static bool classof(const Type *T) {
3798	return T->getTypeClass() == Vector || T->getTypeClass() == ExtVector;
3799	}
3800	};
3801
3802	/// Represents a vector type where either the type or size is dependent.
3803	////
3804	/// For example:
3805	/// \code
3806	/// template<typename T, int Size>
3807	/// class vector {
3808	/// typedef T __attribute__((vector_size(Size))) type;
3809	/// }
3810	/// \endcode
3811	class DependentVectorType : public Type, public llvm::FoldingSetNode {
3812	friend class ASTContext;
3813
3814	QualType ElementType;
3815	Expr *SizeExpr;
3816	SourceLocation Loc;
3817
3818	DependentVectorType(QualType ElementType, QualType CanonType, Expr *SizeExpr,
3819	SourceLocation Loc, VectorKind vecKind);
3820
3821	public:
3822	Expr *getSizeExpr() const { return SizeExpr; }
3823	QualType getElementType() const { return ElementType; }
3824	SourceLocation getAttributeLoc() const { return Loc; }
3825	VectorKind getVectorKind() const {
3826	return VectorKind(VectorTypeBits.VecKind);
3827	}
3828
3829	bool isSugared() const { return false; }
3830	QualType desugar() const { return QualType(this, 0); }
3831
3832	static bool classof(const Type *T) {
3833	return T->getTypeClass() == DependentVector;
3834	}
3835
3836	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
3837	Profile(ID, Context, ElementType: getElementType(), SizeExpr: getSizeExpr(), VecKind: getVectorKind());
3838	}
3839
3840	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3841	QualType ElementType, const Expr *SizeExpr,
3842	VectorKind VecKind);
3843	};
3844
3845	/// ExtVectorType - Extended vector type. This type is created using
3846	/// __attribute__((ext_vector_type(n)), where "n" is the number of elements.
3847	/// Unlike vector_size, ext_vector_type is only allowed on typedef's. This
3848	/// class enables syntactic extensions, like Vector Components for accessing
3849	/// points (as .xyzw), colors (as .rgba), and textures (modeled after OpenGL
3850	/// Shading Language).
3851	class ExtVectorType : public VectorType {
3852	friend class ASTContext; // ASTContext creates these.
3853
3854	ExtVectorType(QualType vecType, unsigned nElements, QualType canonType)
3855	: VectorType(ExtVector, vecType, nElements, canonType,
3856	VectorKind::Generic) {}
3857
3858	public:
3859	static int getPointAccessorIdx(char c) {
3860	switch (c) {
3861	default: return -1;
3862	case 'x': case 'r': return 0;
3863	case 'y': case 'g': return 1;
3864	case 'z': case 'b': return 2;
3865	case 'w': case 'a': return 3;
3866	}
3867	}
3868
3869	static int getNumericAccessorIdx(char c) {
3870	switch (c) {
3871	default: return -1;
3872	case '0': return 0;
3873	case '1': return 1;
3874	case '2': return 2;
3875	case '3': return 3;
3876	case '4': return 4;
3877	case '5': return 5;
3878	case '6': return 6;
3879	case '7': return 7;
3880	case '8': return 8;
3881	case '9': return 9;
3882	case 'A':
3883	case 'a': return 10;
3884	case 'B':
3885	case 'b': return 11;
3886	case 'C':
3887	case 'c': return 12;
3888	case 'D':
3889	case 'd': return 13;
3890	case 'E':
3891	case 'e': return 14;
3892	case 'F':
3893	case 'f': return 15;
3894	}
3895	}
3896
3897	static int getAccessorIdx(char c, bool isNumericAccessor) {
3898	if (isNumericAccessor)
3899	return getNumericAccessorIdx(c);
3900	else
3901	return getPointAccessorIdx(c);
3902	}
3903
3904	bool isAccessorWithinNumElements(char c, bool isNumericAccessor) const {
3905	if (int idx = getAccessorIdx(c, isNumericAccessor)+1)
3906	return unsigned(idx-1) < getNumElements();
3907	return false;
3908	}
3909
3910	bool isSugared() const { return false; }
3911	QualType desugar() const { return QualType(this, 0); }
3912
3913	static bool classof(const Type *T) {
3914	return T->getTypeClass() == ExtVector;
3915	}
3916	};
3917
3918	/// Represents a matrix type, as defined in the Matrix Types clang extensions.
3919	/// __attribute__((matrix_type(rows, columns))), where "rows" specifies
3920	/// number of rows and "columns" specifies the number of columns.
3921	class MatrixType : public Type, public llvm::FoldingSetNode {
3922	protected:
3923	friend class ASTContext;
3924
3925	/// The element type of the matrix.
3926	QualType ElementType;
3927
3928	MatrixType(QualType ElementTy, QualType CanonElementTy);
3929
3930	MatrixType(TypeClass TypeClass, QualType ElementTy, QualType CanonElementTy,
3931	const Expr *RowExpr = nullptr, const Expr *ColumnExpr = nullptr);
3932
3933	public:
3934	/// Returns type of the elements being stored in the matrix
3935	QualType getElementType() const { return ElementType; }
3936
3937	/// Valid elements types are the following:
3938	/// * an integer type (as in C23 6.2.5p22), but excluding enumerated types
3939	/// and _Bool
3940	/// * the standard floating types float or double
3941	/// * a half-precision floating point type, if one is supported on the target
3942	static bool isValidElementType(QualType T) {
3943	return T->isDependentType() ||
3944	(T->isRealType() && !T->isBooleanType() && !T->isEnumeralType());
3945	}
3946
3947	bool isSugared() const { return false; }
3948	QualType desugar() const { return QualType(this, 0); }
3949
3950	static bool classof(const Type *T) {
3951	return T->getTypeClass() == ConstantMatrix ||
3952	T->getTypeClass() == DependentSizedMatrix;
3953	}
3954	};
3955
3956	/// Represents a concrete matrix type with constant number of rows and columns
3957	class ConstantMatrixType final : public MatrixType {
3958	protected:
3959	friend class ASTContext;
3960
3961	/// Number of rows and columns.
3962	unsigned NumRows;
3963	unsigned NumColumns;
3964
3965	static constexpr unsigned MaxElementsPerDimension = (1 << 20) - 1;
3966
3967	ConstantMatrixType(QualType MatrixElementType, unsigned NRows,
3968	unsigned NColumns, QualType CanonElementType);
3969
3970	ConstantMatrixType(TypeClass typeClass, QualType MatrixType, unsigned NRows,
3971	unsigned NColumns, QualType CanonElementType);
3972
3973	public:
3974	/// Returns the number of rows in the matrix.
3975	unsigned getNumRows() const { return NumRows; }
3976
3977	/// Returns the number of columns in the matrix.
3978	unsigned getNumColumns() const { return NumColumns; }
3979
3980	/// Returns the number of elements required to embed the matrix into a vector.
3981	unsigned getNumElementsFlattened() const {
3982	return getNumRows() * getNumColumns();
3983	}
3984
3985	/// Returns true if \p NumElements is a valid matrix dimension.
3986	static constexpr bool isDimensionValid(size_t NumElements) {
3987	return NumElements > 0 && NumElements <= MaxElementsPerDimension;
3988	}
3989
3990	/// Returns the maximum number of elements per dimension.
3991	static constexpr unsigned getMaxElementsPerDimension() {
3992	return MaxElementsPerDimension;
3993	}
3994
3995	void Profile(llvm::FoldingSetNodeID &ID) {
3996	Profile(ID, getElementType(), getNumRows(), getNumColumns(),
3997	getTypeClass());
3998	}
3999
4000	static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
4001	unsigned NumRows, unsigned NumColumns,
4002	TypeClass TypeClass) {
4003	ID.AddPointer(Ptr: ElementType.getAsOpaquePtr());
4004	ID.AddInteger(I: NumRows);
4005	ID.AddInteger(I: NumColumns);
4006	ID.AddInteger(I: TypeClass);
4007	}
4008
4009	static bool classof(const Type *T) {
4010	return T->getTypeClass() == ConstantMatrix;
4011	}
4012	};
4013
4014	/// Represents a matrix type where the type and the number of rows and columns
4015	/// is dependent on a template.
4016	class DependentSizedMatrixType final : public MatrixType {
4017	friend class ASTContext;
4018
4019	Expr *RowExpr;
4020	Expr *ColumnExpr;
4021
4022	SourceLocation loc;
4023
4024	DependentSizedMatrixType(QualType ElementType, QualType CanonicalType,
4025	Expr *RowExpr, Expr *ColumnExpr, SourceLocation loc);
4026
4027	public:
4028	Expr *getRowExpr() const { return RowExpr; }
4029	Expr *getColumnExpr() const { return ColumnExpr; }
4030	SourceLocation getAttributeLoc() const { return loc; }
4031
4032	static bool classof(const Type *T) {
4033	return T->getTypeClass() == DependentSizedMatrix;
4034	}
4035
4036	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
4037	Profile(ID, Context, getElementType(), getRowExpr(), getColumnExpr());
4038	}
4039
4040	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
4041	QualType ElementType, Expr *RowExpr, Expr *ColumnExpr);
4042	};
4043
4044	/// FunctionType - C99 6.7.5.3 - Function Declarators. This is the common base
4045	/// class of FunctionNoProtoType and FunctionProtoType.
4046	class FunctionType : public Type {
4047	// The type returned by the function.
4048	QualType ResultType;
4049
4050	public:
4051	/// Interesting information about a specific parameter that can't simply
4052	/// be reflected in parameter's type. This is only used by FunctionProtoType
4053	/// but is in FunctionType to make this class available during the
4054	/// specification of the bases of FunctionProtoType.
4055	///
4056	/// It makes sense to model language features this way when there's some
4057	/// sort of parameter-specific override (such as an attribute) that
4058	/// affects how the function is called. For example, the ARC ns_consumed
4059	/// attribute changes whether a parameter is passed at +0 (the default)
4060	/// or +1 (ns_consumed). This must be reflected in the function type,
4061	/// but isn't really a change to the parameter type.
4062	///
4063	/// One serious disadvantage of modelling language features this way is
4064	/// that they generally do not work with language features that attempt
4065	/// to destructure types. For example, template argument deduction will
4066	/// not be able to match a parameter declared as
4067	/// T (*)(U)
4068	/// against an argument of type
4069	/// void (*)(__attribute__((ns_consumed)) id)
4070	/// because the substitution of T=void, U=id into the former will
4071	/// not produce the latter.
4072	class ExtParameterInfo {
4073	enum {
4074	ABIMask = 0x0F,
4075	IsConsumed = 0x10,
4076	HasPassObjSize = 0x20,
4077	IsNoEscape = 0x40,
4078	};
4079	unsigned char Data = 0;
4080
4081	public:
4082	ExtParameterInfo() = default;
4083
4084	/// Return the ABI treatment of this parameter.
4085	ParameterABI getABI() const { return ParameterABI(Data & ABIMask); }
4086	ExtParameterInfo withABI(ParameterABI kind) const {
4087	ExtParameterInfo copy = *this;
4088	copy.Data = (copy.Data & ~ABIMask) | unsigned(kind);
4089	return copy;
4090	}
4091
4092	/// Is this parameter considered "consumed" by Objective-C ARC?
4093	/// Consumed parameters must have retainable object type.
4094	bool isConsumed() const { return (Data & IsConsumed); }
4095	ExtParameterInfo withIsConsumed(bool consumed) const {
4096	ExtParameterInfo copy = *this;
4097	if (consumed)
4098	copy.Data |= IsConsumed;
4099	else
4100	copy.Data &= ~IsConsumed;
4101	return copy;
4102	}
4103
4104	bool hasPassObjectSize() const { return Data & HasPassObjSize; }
4105	ExtParameterInfo withHasPassObjectSize() const {
4106	ExtParameterInfo Copy = *this;
4107	Copy.Data |= HasPassObjSize;
4108	return Copy;
4109	}
4110
4111	bool isNoEscape() const { return Data & IsNoEscape; }
4112	ExtParameterInfo withIsNoEscape(bool NoEscape) const {
4113	ExtParameterInfo Copy = *this;
4114	if (NoEscape)
4115	Copy.Data |= IsNoEscape;
4116	else
4117	Copy.Data &= ~IsNoEscape;
4118	return Copy;
4119	}
4120
4121	unsigned char getOpaqueValue() const { return Data; }
4122	static ExtParameterInfo getFromOpaqueValue(unsigned char data) {
4123	ExtParameterInfo result;
4124	result.Data = data;
4125	return result;
4126	}
4127
4128	friend bool operator==(ExtParameterInfo lhs, ExtParameterInfo rhs) {
4129	return lhs.Data == rhs.Data;
4130	}
4131
4132	friend bool operator!=(ExtParameterInfo lhs, ExtParameterInfo rhs) {
4133	return lhs.Data != rhs.Data;
4134	}
4135	};
4136
4137	/// A class which abstracts out some details necessary for
4138	/// making a call.
4139	///
4140	/// It is not actually used directly for storing this information in
4141	/// a FunctionType, although FunctionType does currently use the
4142	/// same bit-pattern.
4143	///
4144	// If you add a field (say Foo), other than the obvious places (both,
4145	// constructors, compile failures), what you need to update is
4146	// * Operator==
4147	// * getFoo
4148	// * withFoo
4149	// * functionType. Add Foo, getFoo.
4150	// * ASTContext::getFooType
4151	// * ASTContext::mergeFunctionTypes
4152	// * FunctionNoProtoType::Profile
4153	// * FunctionProtoType::Profile
4154	// * TypePrinter::PrintFunctionProto
4155	// * AST read and write
4156	// * Codegen
4157	class ExtInfo {
4158	friend class FunctionType;
4159
4160	// Feel free to rearrange or add bits, but if you go over 16, you'll need to
4161	// adjust the Bits field below, and if you add bits, you'll need to adjust
4162	// Type::FunctionTypeBitfields::ExtInfo as well.
4163
4164	// | CC |noreturn|produces|nocallersavedregs|regparm|nocfcheck|cmsenscall|
4165	// |0 .. 4| 5 | 6 | 7 |8 .. 10| 11 | 12 |
4166	//
4167	// regparm is either 0 (no regparm attribute) or the regparm value+1.
4168	enum { CallConvMask = 0x1F };
4169	enum { NoReturnMask = 0x20 };
4170	enum { ProducesResultMask = 0x40 };
4171	enum { NoCallerSavedRegsMask = 0x80 };
4172	enum {
4173	RegParmMask = 0x700,
4174	RegParmOffset = 8
4175	};
4176	enum { NoCfCheckMask = 0x800 };
4177	enum { CmseNSCallMask = 0x1000 };
4178	uint16_t Bits = CC_C;
4179
4180	ExtInfo(unsigned Bits) : Bits(static_cast<uint16_t>(Bits)) {}
4181
4182	public:
4183	// Constructor with no defaults. Use this when you know that you
4184	// have all the elements (when reading an AST file for example).
4185	ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
4186	bool producesResult, bool noCallerSavedRegs, bool NoCfCheck,
4187	bool cmseNSCall) {
4188	assert((!hasRegParm || regParm < 7) && "Invalid regparm value");
4189	Bits = ((unsigned)cc) | (noReturn ? NoReturnMask : 0) |
4190	(producesResult ? ProducesResultMask : 0) |
4191	(noCallerSavedRegs ? NoCallerSavedRegsMask : 0) |
4192	(hasRegParm ? ((regParm + 1) << RegParmOffset) : 0) |
4193	(NoCfCheck ? NoCfCheckMask : 0) |
4194	(cmseNSCall ? CmseNSCallMask : 0);
4195	}
4196
4197	// Constructor with all defaults. Use when for example creating a
4198	// function known to use defaults.
4199	ExtInfo() = default;
4200
4201	// Constructor with just the calling convention, which is an important part
4202	// of the canonical type.
4203	ExtInfo(CallingConv CC) : Bits(CC) {}
4204
4205	bool getNoReturn() const { return Bits & NoReturnMask; }
4206	bool getProducesResult() const { return Bits & ProducesResultMask; }
4207	bool getCmseNSCall() const { return Bits & CmseNSCallMask; }
4208	bool getNoCallerSavedRegs() const { return Bits & NoCallerSavedRegsMask; }
4209	bool getNoCfCheck() const { return Bits & NoCfCheckMask; }
4210	bool getHasRegParm() const { return ((Bits & RegParmMask) >> RegParmOffset) != 0; }
4211
4212	unsigned getRegParm() const {
4213	unsigned RegParm = (Bits & RegParmMask) >> RegParmOffset;
4214	if (RegParm > 0)
4215	--RegParm;
4216	return RegParm;
4217	}
4218
4219	CallingConv getCC() const { return CallingConv(Bits & CallConvMask); }
4220
4221	bool operator==(ExtInfo Other) const {
4222	return Bits == Other.Bits;
4223	}
4224	bool operator!=(ExtInfo Other) const {
4225	return Bits != Other.Bits;
4226	}
4227
4228	// Note that we don't have setters. That is by design, use
4229	// the following with methods instead of mutating these objects.
4230
4231	ExtInfo withNoReturn(bool noReturn) const {
4232	if (noReturn)
4233	return ExtInfo(Bits | NoReturnMask);
4234	else
4235	return ExtInfo(Bits & ~NoReturnMask);
4236	}
4237
4238	ExtInfo withProducesResult(bool producesResult) const {
4239	if (producesResult)
4240	return ExtInfo(Bits | ProducesResultMask);
4241	else
4242	return ExtInfo(Bits & ~ProducesResultMask);
4243	}
4244
4245	ExtInfo withCmseNSCall(bool cmseNSCall) const {
4246	if (cmseNSCall)
4247	return ExtInfo(Bits | CmseNSCallMask);
4248	else
4249	return ExtInfo(Bits & ~CmseNSCallMask);
4250	}
4251
4252	ExtInfo withNoCallerSavedRegs(bool noCallerSavedRegs) const {
4253	if (noCallerSavedRegs)
4254	return ExtInfo(Bits | NoCallerSavedRegsMask);
4255	else
4256	return ExtInfo(Bits & ~NoCallerSavedRegsMask);
4257	}
4258
4259	ExtInfo withNoCfCheck(bool noCfCheck) const {
4260	if (noCfCheck)
4261	return ExtInfo(Bits | NoCfCheckMask);
4262	else
4263	return ExtInfo(Bits & ~NoCfCheckMask);
4264	}
4265
4266	ExtInfo withRegParm(unsigned RegParm) const {
4267	assert(RegParm < 7 && "Invalid regparm value");
4268	return ExtInfo((Bits & ~RegParmMask) |
4269	((RegParm + 1) << RegParmOffset));
4270	}
4271
4272	ExtInfo withCallingConv(CallingConv cc) const {
4273	return ExtInfo((Bits & ~CallConvMask) | (unsigned) cc);
4274	}
4275
4276	void Profile(llvm::FoldingSetNodeID &ID) const {
4277	ID.AddInteger(I: Bits);
4278	}
4279	};
4280
4281	/// A simple holder for a QualType representing a type in an
4282	/// exception specification. Unfortunately needed by FunctionProtoType
4283	/// because TrailingObjects cannot handle repeated types.
4284	struct ExceptionType { QualType Type; };
4285
4286	/// A simple holder for various uncommon bits which do not fit in
4287	/// FunctionTypeBitfields. Aligned to alignof(void *) to maintain the
4288	/// alignment of subsequent objects in TrailingObjects.
4289	struct alignas(void *) FunctionTypeExtraBitfields {
4290	/// The number of types in the exception specification.
4291	/// A whole unsigned is not needed here and according to
4292	/// [implimits] 8 bits would be enough here.
4293	unsigned NumExceptionType : 10;
4294
4295	LLVM_PREFERRED_TYPE(bool)
4296	unsigned HasArmTypeAttributes : 1;
4297
4298	FunctionTypeExtraBitfields()
4299	: NumExceptionType(0), HasArmTypeAttributes(false) {}
4300	};
4301
4302	/// The AArch64 SME ACLE (Arm C/C++ Language Extensions) define a number
4303	/// of function type attributes that can be set on function types, including
4304	/// function pointers.
4305	enum AArch64SMETypeAttributes : unsigned {
4306	SME_NormalFunction = 0,
4307	SME_PStateSMEnabledMask = 1 << 0,
4308	SME_PStateSMCompatibleMask = 1 << 1,
4309
4310	// Describes the value of the state using ArmStateValue.
4311	SME_ZAShift = 2,
4312	SME_ZAMask = 0b111 << SME_ZAShift,
4313	SME_ZT0Shift = 5,
4314	SME_ZT0Mask = 0b111 << SME_ZT0Shift,
4315
4316	SME_AttributeMask =
4317	0b111'111'11 // We can't support more than 8 bits because of
4318	// the bitmask in FunctionTypeExtraBitfields.
4319	};
4320
4321	enum ArmStateValue : unsigned {
4322	ARM_None = 0,
4323	ARM_Preserves = 1,
4324	ARM_In = 2,
4325	ARM_Out = 3,
4326	ARM_InOut = 4,
4327	};
4328
4329	static ArmStateValue getArmZAState(unsigned AttrBits) {
4330	return (ArmStateValue)((AttrBits & SME_ZAMask) >> SME_ZAShift);
4331	}
4332
4333	static ArmStateValue getArmZT0State(unsigned AttrBits) {
4334	return (ArmStateValue)((AttrBits & SME_ZT0Mask) >> SME_ZT0Shift);
4335	}
4336
4337	/// A holder for Arm type attributes as described in the Arm C/C++
4338	/// Language extensions which are not particularly common to all
4339	/// types and therefore accounted separately from FunctionTypeBitfields.
4340	struct alignas(void *) FunctionTypeArmAttributes {
4341	/// Any AArch64 SME ACLE type attributes that need to be propagated
4342	/// on declarations and function pointers.
4343	unsigned AArch64SMEAttributes : 8;
4344
4345	FunctionTypeArmAttributes() : AArch64SMEAttributes(SME_NormalFunction) {}
4346	};
4347
4348	protected:
4349	FunctionType(TypeClass tc, QualType res, QualType Canonical,
4350	TypeDependence Dependence, ExtInfo Info)
4351	: Type(tc, Canonical, Dependence), ResultType(res) {
4352	FunctionTypeBits.ExtInfo = Info.Bits;
4353	}
4354
4355	Qualifiers getFastTypeQuals() const {
4356	if (isFunctionProtoType())
4357	return Qualifiers::fromFastMask(FunctionTypeBits.FastTypeQuals);
4358
4359	return Qualifiers();
4360	}
4361
4362	public:
4363	QualType getReturnType() const { return ResultType; }
4364
4365	bool getHasRegParm() const { return getExtInfo().getHasRegParm(); }
4366	unsigned getRegParmType() const { return getExtInfo().getRegParm(); }
4367
4368	/// Determine whether this function type includes the GNU noreturn
4369	/// attribute. The C++11 [[noreturn]] attribute does not affect the function
4370	/// type.
4371	bool getNoReturnAttr() const { return getExtInfo().getNoReturn(); }
4372
4373	bool getCmseNSCallAttr() const { return getExtInfo().getCmseNSCall(); }
4374	CallingConv getCallConv() const { return getExtInfo().getCC(); }
4375	ExtInfo getExtInfo() const { return ExtInfo(FunctionTypeBits.ExtInfo); }
4376
4377	static_assert((~Qualifiers::FastMask & Qualifiers::CVRMask) == 0,
4378	"Const, volatile and restrict are assumed to be a subset of "
4379	"the fast qualifiers.");
4380
4381	bool isConst() const { return getFastTypeQuals().hasConst(); }
4382	bool isVolatile() const { return getFastTypeQuals().hasVolatile(); }
4383	bool isRestrict() const { return getFastTypeQuals().hasRestrict(); }
4384
4385	/// Determine the type of an expression that calls a function of
4386	/// this type.
4387	QualType getCallResultType(const ASTContext &Context) const {
4388	return getReturnType().getNonLValueExprType(Context);
4389	}
4390
4391	static StringRef getNameForCallConv(CallingConv CC);
4392
4393	static bool classof(const Type *T) {
4394	return T->getTypeClass() == FunctionNoProto ||
4395	T->getTypeClass() == FunctionProto;
4396	}
4397	};
4398
4399	/// Represents a K&R-style 'int foo()' function, which has
4400	/// no information available about its arguments.
4401	class FunctionNoProtoType : public FunctionType, public llvm::FoldingSetNode {
4402	friend class ASTContext; // ASTContext creates these.
4403
4404	FunctionNoProtoType(QualType Result, QualType Canonical, ExtInfo Info)
4405	: FunctionType(FunctionNoProto, Result, Canonical,
4406	Result->getDependence() &
4407	~(TypeDependence::DependentInstantiation |
4408	TypeDependence::UnexpandedPack),
4409	Info) {}
4410
4411	public:
4412	// No additional state past what FunctionType provides.
4413
4414	bool isSugared() const { return false; }
4415	QualType desugar() const { return QualType(this, 0); }
4416
4417	void Profile(llvm::FoldingSetNodeID &ID) {
4418	Profile(ID, getReturnType(), getExtInfo());
4419	}
4420
4421	static void Profile(llvm::FoldingSetNodeID &ID, QualType ResultType,
4422	ExtInfo Info) {
4423	Info.Profile(ID);
4424	ID.AddPointer(Ptr: ResultType.getAsOpaquePtr());
4425	}
4426
4427	static bool classof(const Type *T) {
4428	return T->getTypeClass() == FunctionNoProto;
4429	}
4430	};
4431
4432	/// Represents a prototype with parameter type info, e.g.
4433	/// 'int foo(int)' or 'int foo(void)'. 'void' is represented as having no
4434	/// parameters, not as having a single void parameter. Such a type can have
4435	/// an exception specification, but this specification is not part of the
4436	/// canonical type. FunctionProtoType has several trailing objects, some of
4437	/// which optional. For more information about the trailing objects see
4438	/// the first comment inside FunctionProtoType.
4439	class FunctionProtoType final
4440	: public FunctionType,
4441	public llvm::FoldingSetNode,
4442	private llvm::TrailingObjects<
4443	FunctionProtoType, QualType, SourceLocation,
4444	FunctionType::FunctionTypeExtraBitfields,
4445	FunctionType::FunctionTypeArmAttributes, FunctionType::ExceptionType,
4446	Expr *, FunctionDecl *, FunctionType::ExtParameterInfo, Qualifiers> {
4447	friend class ASTContext; // ASTContext creates these.
4448	friend TrailingObjects;
4449
4450	// FunctionProtoType is followed by several trailing objects, some of
4451	// which optional. They are in order:
4452	//
4453	// * An array of getNumParams() QualType holding the parameter types.
4454	// Always present. Note that for the vast majority of FunctionProtoType,
4455	// these will be the only trailing objects.
4456	//
4457	// * Optionally if the function is variadic, the SourceLocation of the
4458	// ellipsis.
4459	//
4460	// * Optionally if some extra data is stored in FunctionTypeExtraBitfields
4461	// (see FunctionTypeExtraBitfields and FunctionTypeBitfields):
4462	// a single FunctionTypeExtraBitfields. Present if and only if
4463	// hasExtraBitfields() is true.
4464	//
4465	// * Optionally exactly one of:
4466	// * an array of getNumExceptions() ExceptionType,
4467	// * a single Expr *,
4468	// * a pair of FunctionDecl *,
4469	// * a single FunctionDecl *
4470	// used to store information about the various types of exception
4471	// specification. See getExceptionSpecSize for the details.
4472	//
4473	// * Optionally an array of getNumParams() ExtParameterInfo holding
4474	// an ExtParameterInfo for each of the parameters. Present if and
4475	// only if hasExtParameterInfos() is true.
4476	//
4477	// * Optionally a Qualifiers object to represent extra qualifiers that can't
4478	// be represented by FunctionTypeBitfields.FastTypeQuals. Present if and only
4479	// if hasExtQualifiers() is true.
4480	//
4481	// The optional FunctionTypeExtraBitfields has to be before the data
4482	// related to the exception specification since it contains the number
4483	// of exception types.
4484	//
4485	// We put the ExtParameterInfos last. If all were equal, it would make
4486	// more sense to put these before the exception specification, because
4487	// it's much easier to skip past them compared to the elaborate switch
4488	// required to skip the exception specification. However, all is not
4489	// equal; ExtParameterInfos are used to model very uncommon features,
4490	// and it's better not to burden the more common paths.
4491
4492	public:
4493	/// Holds information about the various types of exception specification.
4494	/// ExceptionSpecInfo is not stored as such in FunctionProtoType but is
4495	/// used to group together the various bits of information about the
4496	/// exception specification.
4497	struct ExceptionSpecInfo {
4498	/// The kind of exception specification this is.
4499	ExceptionSpecificationType Type = EST_None;
4500
4501	/// Explicitly-specified list of exception types.
4502	ArrayRef<QualType> Exceptions;
4503
4504	/// Noexcept expression, if this is a computed noexcept specification.
4505	Expr *NoexceptExpr = nullptr;
4506
4507	/// The function whose exception specification this is, for
4508	/// EST_Unevaluated and EST_Uninstantiated.
4509	FunctionDecl *SourceDecl = nullptr;
4510
4511	/// The function template whose exception specification this is instantiated
4512	/// from, for EST_Uninstantiated.
4513	FunctionDecl *SourceTemplate = nullptr;
4514
4515	ExceptionSpecInfo() = default;
4516
4517	ExceptionSpecInfo(ExceptionSpecificationType EST) : Type(EST) {}
4518
4519	void instantiate();
4520	};
4521
4522	/// Extra information about a function prototype. ExtProtoInfo is not
4523	/// stored as such in FunctionProtoType but is used to group together
4524	/// the various bits of extra information about a function prototype.
4525	struct ExtProtoInfo {
4526	FunctionType::ExtInfo ExtInfo;
4527	unsigned Variadic : 1;
4528	unsigned HasTrailingReturn : 1;
4529	unsigned AArch64SMEAttributes : 8;
4530	Qualifiers TypeQuals;
4531	RefQualifierKind RefQualifier = RQ_None;
4532	ExceptionSpecInfo ExceptionSpec;
4533	const ExtParameterInfo *ExtParameterInfos = nullptr;
4534	SourceLocation EllipsisLoc;
4535
4536	ExtProtoInfo()
4537	: Variadic(false), HasTrailingReturn(false),
4538	AArch64SMEAttributes(SME_NormalFunction) {}
4539
4540	ExtProtoInfo(CallingConv CC)
4541	: ExtInfo(CC), Variadic(false), HasTrailingReturn(false),
4542	AArch64SMEAttributes(SME_NormalFunction) {}
4543
4544	ExtProtoInfo withExceptionSpec(const ExceptionSpecInfo &ESI) {
4545	ExtProtoInfo Result(*this);
4546	Result.ExceptionSpec = ESI;
4547	return Result;
4548	}
4549
4550	bool requiresFunctionProtoTypeExtraBitfields() const {
4551	return ExceptionSpec.Type == EST_Dynamic ||
4552	requiresFunctionProtoTypeArmAttributes();
4553	}
4554
4555	bool requiresFunctionProtoTypeArmAttributes() const {
4556	return AArch64SMEAttributes != SME_NormalFunction;
4557	}
4558
4559	void setArmSMEAttribute(AArch64SMETypeAttributes Kind, bool Enable = true) {
4560	if (Enable)
4561	AArch64SMEAttributes |= Kind;
4562	else
4563	AArch64SMEAttributes &= ~Kind;
4564	}
4565	};
4566
4567	private:
4568	unsigned numTrailingObjects(OverloadToken<QualType>) const {
4569	return getNumParams();
4570	}
4571
4572	unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
4573	return isVariadic();
4574	}
4575
4576	unsigned numTrailingObjects(OverloadToken<FunctionTypeArmAttributes>) const {
4577	return hasArmTypeAttributes();
4578	}
4579
4580	unsigned numTrailingObjects(OverloadToken<FunctionTypeExtraBitfields>) const {
4581	return hasExtraBitfields();
4582	}
4583
4584	unsigned numTrailingObjects(OverloadToken<ExceptionType>) const {
4585	return getExceptionSpecSize().NumExceptionType;
4586	}
4587
4588	unsigned numTrailingObjects(OverloadToken<Expr *>) const {
4589	return getExceptionSpecSize().NumExprPtr;
4590	}
4591
4592	unsigned numTrailingObjects(OverloadToken<FunctionDecl *>) const {
4593	return getExceptionSpecSize().NumFunctionDeclPtr;
4594	}
4595
4596	unsigned numTrailingObjects(OverloadToken<ExtParameterInfo>) const {
4597	return hasExtParameterInfos() ? getNumParams() : 0;
4598	}
4599
4600	/// Determine whether there are any argument types that
4601	/// contain an unexpanded parameter pack.
4602	static bool containsAnyUnexpandedParameterPack(const QualType *ArgArray,
4603	unsigned numArgs) {
4604	for (unsigned Idx = 0; Idx < numArgs; ++Idx)
4605	if (ArgArray[Idx]->containsUnexpandedParameterPack())
4606	return true;
4607
4608	return false;
4609	}
4610
4611	FunctionProtoType(QualType result, ArrayRef<QualType> params,
4612	QualType canonical, const ExtProtoInfo &epi);
4613
4614	/// This struct is returned by getExceptionSpecSize and is used to
4615	/// translate an ExceptionSpecificationType to the number and kind
4616	/// of trailing objects related to the exception specification.
4617	struct ExceptionSpecSizeHolder {
4618	unsigned NumExceptionType;
4619	unsigned NumExprPtr;
4620	unsigned NumFunctionDeclPtr;
4621	};
4622
4623	/// Return the number and kind of trailing objects
4624	/// related to the exception specification.
4625	static ExceptionSpecSizeHolder
4626	getExceptionSpecSize(ExceptionSpecificationType EST, unsigned NumExceptions) {
4627	switch (EST) {
4628	case EST_None:
4629	case EST_DynamicNone:
4630	case EST_MSAny:
4631	case EST_BasicNoexcept:
4632	case EST_Unparsed:
4633	case EST_NoThrow:
4634	return {.NumExceptionType: 0, .NumExprPtr: 0, .NumFunctionDeclPtr: 0};
4635
4636	case EST_Dynamic:
4637	return {.NumExceptionType: NumExceptions, .NumExprPtr: 0, .NumFunctionDeclPtr: 0};
4638
4639	case EST_DependentNoexcept:
4640	case EST_NoexceptFalse:
4641	case EST_NoexceptTrue:
4642	return {.NumExceptionType: 0, .NumExprPtr: 1, .NumFunctionDeclPtr: 0};
4643
4644	case EST_Uninstantiated:
4645	return {.NumExceptionType: 0, .NumExprPtr: 0, .NumFunctionDeclPtr: 2};
4646
4647	case EST_Unevaluated:
4648	return {.NumExceptionType: 0, .NumExprPtr: 0, .NumFunctionDeclPtr: 1};
4649	}
4650	llvm_unreachable("bad exception specification kind");
4651	}
4652
4653	/// Return the number and kind of trailing objects
4654	/// related to the exception specification.
4655	ExceptionSpecSizeHolder getExceptionSpecSize() const {
4656	return getExceptionSpecSize(EST: getExceptionSpecType(), NumExceptions: getNumExceptions());
4657	}
4658
4659	/// Whether the trailing FunctionTypeExtraBitfields is present.
4660	bool hasExtraBitfields() const {
4661	assert((getExceptionSpecType() != EST_Dynamic ||
4662	FunctionTypeBits.HasExtraBitfields) &&
4663	"ExtraBitfields are required for given ExceptionSpecType");
4664	return FunctionTypeBits.HasExtraBitfields;
4665
4666	}
4667
4668	bool hasArmTypeAttributes() const {
4669	return FunctionTypeBits.HasExtraBitfields &&
4670	getTrailingObjects<FunctionTypeExtraBitfields>()
4671	->HasArmTypeAttributes;
4672	}
4673
4674	bool hasExtQualifiers() const {
4675	return FunctionTypeBits.HasExtQuals;
4676	}
4677
4678	public:
4679	unsigned getNumParams() const { return FunctionTypeBits.NumParams; }
4680
4681	QualType getParamType(unsigned i) const {
4682	assert(i < getNumParams() && "invalid parameter index");
4683	return param_type_begin()[i];
4684	}
4685
4686	ArrayRef<QualType> getParamTypes() const {
4687	return llvm::ArrayRef(param_type_begin(), param_type_end());
4688	}
4689
4690	ExtProtoInfo getExtProtoInfo() const {
4691	ExtProtoInfo EPI;
4692	EPI.ExtInfo = getExtInfo();
4693	EPI.Variadic = isVariadic();
4694	EPI.EllipsisLoc = getEllipsisLoc();
4695	EPI.HasTrailingReturn = hasTrailingReturn();
4696	EPI.ExceptionSpec = getExceptionSpecInfo();
4697	EPI.TypeQuals = getMethodQuals();
4698	EPI.RefQualifier = getRefQualifier();
4699	EPI.ExtParameterInfos = getExtParameterInfosOrNull();
4700	EPI.AArch64SMEAttributes = getAArch64SMEAttributes();
4701	return EPI;
4702	}
4703
4704	/// Get the kind of exception specification on this function.
4705	ExceptionSpecificationType getExceptionSpecType() const {
4706	return static_cast<ExceptionSpecificationType>(
4707	FunctionTypeBits.ExceptionSpecType);
4708	}
4709
4710	/// Return whether this function has any kind of exception spec.
4711	bool hasExceptionSpec() const { return getExceptionSpecType() != EST_None; }
4712
4713	/// Return whether this function has a dynamic (throw) exception spec.
4714	bool hasDynamicExceptionSpec() const {
4715	return isDynamicExceptionSpec(ESpecType: getExceptionSpecType());
4716	}
4717
4718	/// Return whether this function has a noexcept exception spec.
4719	bool hasNoexceptExceptionSpec() const {
4720	return isNoexceptExceptionSpec(ESpecType: getExceptionSpecType());
4721	}
4722
4723	/// Return whether this function has a dependent exception spec.
4724	bool hasDependentExceptionSpec() const;
4725
4726	/// Return whether this function has an instantiation-dependent exception
4727	/// spec.
4728	bool hasInstantiationDependentExceptionSpec() const;
4729
4730	/// Return all the available information about this type's exception spec.
4731	ExceptionSpecInfo getExceptionSpecInfo() const {
4732	ExceptionSpecInfo Result;
4733	Result.Type = getExceptionSpecType();
4734	if (Result.Type == EST_Dynamic) {
4735	Result.Exceptions = exceptions();
4736	} else if (isComputedNoexcept(ESpecType: Result.Type)) {
4737	Result.NoexceptExpr = getNoexceptExpr();
4738	} else if (Result.Type == EST_Uninstantiated) {
4739	Result.SourceDecl = getExceptionSpecDecl();
4740	Result.SourceTemplate = getExceptionSpecTemplate();
4741	} else if (Result.Type == EST_Unevaluated) {
4742	Result.SourceDecl = getExceptionSpecDecl();
4743	}
4744	return Result;
4745	}
4746
4747	/// Return the number of types in the exception specification.
4748	unsigned getNumExceptions() const {
4749	return getExceptionSpecType() == EST_Dynamic
4750	? getTrailingObjects<FunctionTypeExtraBitfields>()
4751	->NumExceptionType
4752	: 0;
4753	}
4754
4755	/// Return the ith exception type, where 0 <= i < getNumExceptions().
4756	QualType getExceptionType(unsigned i) const {
4757	assert(i < getNumExceptions() && "Invalid exception number!");
4758	return exception_begin()[i];
4759	}
4760
4761	/// Return the expression inside noexcept(expression), or a null pointer
4762	/// if there is none (because the exception spec is not of this form).
4763	Expr *getNoexceptExpr() const {
4764	if (!isComputedNoexcept(ESpecType: getExceptionSpecType()))
4765	return nullptr;
4766	return *getTrailingObjects<Expr *>();
4767	}
4768
4769	/// If this function type has an exception specification which hasn't
4770	/// been determined yet (either because it has not been evaluated or because
4771	/// it has not been instantiated), this is the function whose exception
4772	/// specification is represented by this type.
4773	FunctionDecl *getExceptionSpecDecl() const {
4774	if (getExceptionSpecType() != EST_Uninstantiated &&
4775	getExceptionSpecType() != EST_Unevaluated)
4776	return nullptr;
4777	return getTrailingObjects<FunctionDecl *>()[0];
4778	}
4779
4780	/// If this function type has an uninstantiated exception
4781	/// specification, this is the function whose exception specification
4782	/// should be instantiated to find the exception specification for
4783	/// this type.
4784	FunctionDecl *getExceptionSpecTemplate() const {
4785	if (getExceptionSpecType() != EST_Uninstantiated)
4786	return nullptr;
4787	return getTrailingObjects<FunctionDecl *>()[1];
4788	}
4789
4790	/// Determine whether this function type has a non-throwing exception
4791	/// specification.
4792	CanThrowResult canThrow() const;
4793
4794	/// Determine whether this function type has a non-throwing exception
4795	/// specification. If this depends on template arguments, returns
4796	/// \c ResultIfDependent.
4797	bool isNothrow(bool ResultIfDependent = false) const {
4798	return ResultIfDependent ? canThrow() != CT_Can : canThrow() == CT_Cannot;
4799	}
4800
4801	/// Whether this function prototype is variadic.
4802	bool isVariadic() const { return FunctionTypeBits.Variadic; }
4803
4804	SourceLocation getEllipsisLoc() const {
4805	return isVariadic() ? *getTrailingObjects<SourceLocation>()
4806	: SourceLocation();
4807	}
4808
4809	/// Determines whether this function prototype contains a
4810	/// parameter pack at the end.
4811	///
4812	/// A function template whose last parameter is a parameter pack can be
4813	/// called with an arbitrary number of arguments, much like a variadic
4814	/// function.
4815	bool isTemplateVariadic() const;
4816
4817	/// Whether this function prototype has a trailing return type.
4818	bool hasTrailingReturn() const { return FunctionTypeBits.HasTrailingReturn; }
4819
4820	Qualifiers getMethodQuals() const {
4821	if (hasExtQualifiers())
4822	return *getTrailingObjects<Qualifiers>();
4823	else
4824	return getFastTypeQuals();
4825	}
4826
4827	/// Retrieve the ref-qualifier associated with this function type.
4828	RefQualifierKind getRefQualifier() const {
4829	return static_cast<RefQualifierKind>(FunctionTypeBits.RefQualifier);
4830	}
4831
4832	using param_type_iterator = const QualType *;
4833
4834	ArrayRef<QualType> param_types() const {
4835	return llvm::ArrayRef(param_type_begin(), param_type_end());
4836	}
4837
4838	param_type_iterator param_type_begin() const {
4839	return getTrailingObjects<QualType>();
4840	}
4841
4842	param_type_iterator param_type_end() const {
4843	return param_type_begin() + getNumParams();
4844	}
4845
4846	using exception_iterator = const QualType *;
4847
4848	ArrayRef<QualType> exceptions() const {
4849	return llvm::ArrayRef(exception_begin(), exception_end());
4850	}
4851
4852	exception_iterator exception_begin() const {
4853	return reinterpret_cast<exception_iterator>(
4854	getTrailingObjects<ExceptionType>());
4855	}
4856
4857	exception_iterator exception_end() const {
4858	return exception_begin() + getNumExceptions();
4859	}
4860
4861	/// Is there any interesting extra information for any of the parameters
4862	/// of this function type?
4863	bool hasExtParameterInfos() const {
4864	return FunctionTypeBits.HasExtParameterInfos;
4865	}
4866
4867	ArrayRef<ExtParameterInfo> getExtParameterInfos() const {
4868	assert(hasExtParameterInfos());
4869	return ArrayRef<ExtParameterInfo>(getTrailingObjects<ExtParameterInfo>(),
4870	getNumParams());
4871	}
4872
4873	/// Return a pointer to the beginning of the array of extra parameter
4874	/// information, if present, or else null if none of the parameters
4875	/// carry it. This is equivalent to getExtProtoInfo().ExtParameterInfos.
4876	const ExtParameterInfo *getExtParameterInfosOrNull() const {
4877	if (!hasExtParameterInfos())
4878	return nullptr;
4879	return getTrailingObjects<ExtParameterInfo>();
4880	}
4881
4882	/// Return a bitmask describing the SME attributes on the function type, see
4883	/// AArch64SMETypeAttributes for their values.
4884	unsigned getAArch64SMEAttributes() const {
4885	if (!hasArmTypeAttributes())
4886	return SME_NormalFunction;
4887	return getTrailingObjects<FunctionTypeArmAttributes>()
4888	->AArch64SMEAttributes;
4889	}
4890
4891	ExtParameterInfo getExtParameterInfo(unsigned I) const {
4892	assert(I < getNumParams() && "parameter index out of range");
4893	if (hasExtParameterInfos())
4894	return getTrailingObjects<ExtParameterInfo>()[I];
4895	return ExtParameterInfo();
4896	}
4897
4898	ParameterABI getParameterABI(unsigned I) const {
4899	assert(I < getNumParams() && "parameter index out of range");
4900	if (hasExtParameterInfos())
4901	return getTrailingObjects<ExtParameterInfo>()[I].getABI();
4902	return ParameterABI::Ordinary;
4903	}
4904
4905	bool isParamConsumed(unsigned I) const {
4906	assert(I < getNumParams() && "parameter index out of range");
4907	if (hasExtParameterInfos())
4908	return getTrailingObjects<ExtParameterInfo>()[I].isConsumed();
4909	return false;
4910	}
4911
4912	bool isSugared() const { return false; }
4913	QualType desugar() const { return QualType(this, 0); }
4914
4915	void printExceptionSpecification(raw_ostream &OS,
4916	const PrintingPolicy &Policy) const;
4917
4918	static bool classof(const Type *T) {
4919	return T->getTypeClass() == FunctionProto;
4920	}
4921
4922	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx);
4923	static void Profile(llvm::FoldingSetNodeID &ID, QualType Result,
4924	param_type_iterator ArgTys, unsigned NumArgs,
4925	const ExtProtoInfo &EPI, const ASTContext &Context,
4926	bool Canonical);
4927	};
4928
4929	/// Represents the dependent type named by a dependently-scoped
4930	/// typename using declaration, e.g.
4931	/// using typename Base<T>::foo;
4932	///
4933	/// Template instantiation turns these into the underlying type.
4934	class UnresolvedUsingType : public Type {
4935	friend class ASTContext; // ASTContext creates these.
4936
4937	UnresolvedUsingTypenameDecl *Decl;
4938
4939	UnresolvedUsingType(const UnresolvedUsingTypenameDecl *D)
4940	: Type(UnresolvedUsing, QualType(),
4941	TypeDependence::DependentInstantiation),
4942	Decl(const_cast<UnresolvedUsingTypenameDecl *>(D)) {}
4943
4944	public:
4945	UnresolvedUsingTypenameDecl *getDecl() const { return Decl; }
4946
4947	bool isSugared() const { return false; }
4948	QualType desugar() const { return QualType(this, 0); }
4949
4950	static bool classof(const Type *T) {
4951	return T->getTypeClass() == UnresolvedUsing;
4952	}
4953
4954	void Profile(llvm::FoldingSetNodeID &ID) {
4955	return Profile(ID, D: Decl);
4956	}
4957
4958	static void Profile(llvm::FoldingSetNodeID &ID,
4959	UnresolvedUsingTypenameDecl *D) {
4960	ID.AddPointer(Ptr: D);
4961	}
4962	};
4963
4964	class UsingType final : public Type,
4965	public llvm::FoldingSetNode,
4966	private llvm::TrailingObjects<UsingType, QualType> {
4967	UsingShadowDecl *Found;
4968	friend class ASTContext; // ASTContext creates these.
4969	friend TrailingObjects;
4970
4971	UsingType(const UsingShadowDecl *Found, QualType Underlying, QualType Canon);
4972
4973	public:
4974	UsingShadowDecl *getFoundDecl() const { return Found; }
4975	QualType getUnderlyingType() const;
4976
4977	bool isSugared() const { return true; }
4978
4979	// This always has the 'same' type as declared, but not necessarily identical.
4980	QualType desugar() const { return getUnderlyingType(); }
4981
4982	// Internal helper, for debugging purposes.
4983	bool typeMatchesDecl() const { return !UsingBits.hasTypeDifferentFromDecl; }
4984
4985	void Profile(llvm::FoldingSetNodeID &ID) {
4986	Profile(ID, Found, Underlying: getUnderlyingType());
4987	}
4988	static void Profile(llvm::FoldingSetNodeID &ID, const UsingShadowDecl *Found,
4989	QualType Underlying) {
4990	ID.AddPointer(Ptr: Found);
4991	Underlying.Profile(ID);
4992	}
4993	static bool classof(const Type *T) { return T->getTypeClass() == Using; }
4994	};
4995
4996	class TypedefType final : public Type,
4997	public llvm::FoldingSetNode,
4998	private llvm::TrailingObjects<TypedefType, QualType> {
4999	TypedefNameDecl *Decl;
5000	friend class ASTContext; // ASTContext creates these.
5001	friend TrailingObjects;
5002
5003	TypedefType(TypeClass tc, const TypedefNameDecl *D, QualType underlying,
5004	QualType can);
5005
5006	public:
5007	TypedefNameDecl *getDecl() const { return Decl; }
5008
5009	bool isSugared() const { return true; }
5010
5011	// This always has the 'same' type as declared, but not necessarily identical.
5012	QualType desugar() const;
5013
5014	// Internal helper, for debugging purposes.
5015	bool typeMatchesDecl() const { return !TypedefBits.hasTypeDifferentFromDecl; }
5016
5017	void Profile(llvm::FoldingSetNodeID &ID) {
5018	Profile(ID, Decl, Underlying: typeMatchesDecl() ? QualType() : desugar());
5019	}
5020	static void Profile(llvm::FoldingSetNodeID &ID, const TypedefNameDecl *Decl,
5021	QualType Underlying) {
5022	ID.AddPointer(Ptr: Decl);
5023	if (!Underlying.isNull())
5024	Underlying.Profile(ID);
5025	}
5026
5027	static bool classof(const Type *T) { return T->getTypeClass() == Typedef; }
5028	};
5029
5030	/// Sugar type that represents a type that was qualified by a qualifier written
5031	/// as a macro invocation.
5032	class MacroQualifiedType : public Type {
5033	friend class ASTContext; // ASTContext creates these.
5034
5035	QualType UnderlyingTy;
5036	const IdentifierInfo *MacroII;
5037
5038	MacroQualifiedType(QualType UnderlyingTy, QualType CanonTy,
5039	const IdentifierInfo *MacroII)
5040	: Type(MacroQualified, CanonTy, UnderlyingTy->getDependence()),
5041	UnderlyingTy(UnderlyingTy), MacroII(MacroII) {
5042	assert(isa<AttributedType>(UnderlyingTy) &&
5043	"Expected a macro qualified type to only wrap attributed types.");
5044	}
5045
5046	public:
5047	const IdentifierInfo *getMacroIdentifier() const { return MacroII; }
5048	QualType getUnderlyingType() const { return UnderlyingTy; }
5049
5050	/// Return this attributed type's modified type with no qualifiers attached to
5051	/// it.
5052	QualType getModifiedType() const;
5053
5054	bool isSugared() const { return true; }
5055	QualType desugar() const;
5056
5057	static bool classof(const Type *T) {
5058	return T->getTypeClass() == MacroQualified;
5059	}
5060	};
5061
5062	/// Represents a `typeof` (or __typeof__) expression (a C23 feature and GCC
5063	/// extension) or a `typeof_unqual` expression (a C23 feature).
5064	class TypeOfExprType : public Type {
5065	Expr *TOExpr;
5066
5067	protected:
5068	friend class ASTContext; // ASTContext creates these.
5069
5070	TypeOfExprType(Expr *E, TypeOfKind Kind, QualType Can = QualType());
5071
5072	public:
5073	Expr *getUnderlyingExpr() const { return TOExpr; }
5074
5075	/// Returns the kind of 'typeof' type this is.
5076	TypeOfKind getKind() const {
5077	return TypeOfBits.IsUnqual ? TypeOfKind::Unqualified
5078	: TypeOfKind::Qualified;
5079	}
5080
5081	/// Remove a single level of sugar.
5082	QualType desugar() const;
5083
5084	/// Returns whether this type directly provides sugar.
5085	bool isSugared() const;
5086
5087	static bool classof(const Type *T) { return T->getTypeClass() == TypeOfExpr; }
5088	};
5089
5090	/// Internal representation of canonical, dependent
5091	/// `typeof(expr)` types.
5092	///
5093	/// This class is used internally by the ASTContext to manage
5094	/// canonical, dependent types, only. Clients will only see instances
5095	/// of this class via TypeOfExprType nodes.
5096	class DependentTypeOfExprType : public TypeOfExprType,
5097	public llvm::FoldingSetNode {
5098	public:
5099	DependentTypeOfExprType(Expr *E, TypeOfKind Kind) : TypeOfExprType(E, Kind) {}
5100
5101	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
5102	Profile(ID, Context, getUnderlyingExpr(),
5103	getKind() == TypeOfKind::Unqualified);
5104	}
5105
5106	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
5107	Expr *E, bool IsUnqual);
5108	};
5109
5110	/// Represents `typeof(type)`, a C23 feature and GCC extension, or
5111	/// `typeof_unqual(type), a C23 feature.
5112	class TypeOfType : public Type {
5113	friend class ASTContext; // ASTContext creates these.
5114
5115	QualType TOType;
5116
5117	TypeOfType(QualType T, QualType Can, TypeOfKind Kind)
5118	: Type(TypeOf,
5119	Kind == TypeOfKind::Unqualified ? Can.getAtomicUnqualifiedType()
5120	: Can,
5121	T->getDependence()),
5122	TOType(T) {
5123	TypeOfBits.IsUnqual = Kind == TypeOfKind::Unqualified;
5124	}
5125
5126	public:
5127	QualType getUnmodifiedType() const { return TOType; }
5128
5129	/// Remove a single level of sugar.
5130	QualType desugar() const {
5131	QualType QT = getUnmodifiedType();
5132	return TypeOfBits.IsUnqual ? QT.getAtomicUnqualifiedType() : QT;
5133	}
5134
5135	/// Returns whether this type directly provides sugar.
5136	bool isSugared() const { return true; }
5137
5138	/// Returns the kind of 'typeof' type this is.
5139	TypeOfKind getKind() const {
5140	return TypeOfBits.IsUnqual ? TypeOfKind::Unqualified
5141	: TypeOfKind::Qualified;
5142	}
5143
5144	static bool classof(const Type *T) { return T->getTypeClass() == TypeOf; }
5145	};
5146
5147	/// Represents the type `decltype(expr)` (C++11).
5148	class DecltypeType : public Type {
5149	Expr *E;
5150	QualType UnderlyingType;
5151
5152	protected:
5153	friend class ASTContext; // ASTContext creates these.
5154
5155	DecltypeType(Expr *E, QualType underlyingType, QualType can = QualType());
5156
5157	public:
5158	Expr *getUnderlyingExpr() const { return E; }
5159	QualType getUnderlyingType() const { return UnderlyingType; }
5160
5161	/// Remove a single level of sugar.
5162	QualType desugar() const;
5163
5164	/// Returns whether this type directly provides sugar.
5165	bool isSugared() const;
5166
5167	static bool classof(const Type *T) { return T->getTypeClass() == Decltype; }
5168	};
5169
5170	/// Internal representation of canonical, dependent
5171	/// decltype(expr) types.
5172	///
5173	/// This class is used internally by the ASTContext to manage
5174	/// canonical, dependent types, only. Clients will only see instances
5175	/// of this class via DecltypeType nodes.
5176	class DependentDecltypeType : public DecltypeType, public llvm::FoldingSetNode {
5177	public:
5178	DependentDecltypeType(Expr *E, QualType UnderlyingTpe);
5179
5180	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
5181	Profile(ID, Context, getUnderlyingExpr());
5182	}
5183
5184	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
5185	Expr *E);
5186	};
5187
5188	class PackIndexingType final
5189	: public Type,
5190	public llvm::FoldingSetNode,
5191	private llvm::TrailingObjects<PackIndexingType, QualType> {
5192	friend TrailingObjects;
5193
5194	const ASTContext &Context;
5195	QualType Pattern;
5196	Expr *IndexExpr;
5197
5198	unsigned Size;
5199
5200	protected:
5201	friend class ASTContext; // ASTContext creates these.
5202	PackIndexingType(const ASTContext &Context, QualType Canonical,
5203	QualType Pattern, Expr *IndexExpr,
5204	ArrayRef<QualType> Expansions = {});
5205
5206	public:
5207	Expr *getIndexExpr() const { return IndexExpr; }
5208	QualType getPattern() const { return Pattern; }
5209
5210	bool isSugared() const { return hasSelectedType(); }
5211
5212	QualType desugar() const {
5213	if (hasSelectedType())
5214	return getSelectedType();
5215	return QualType(this, 0);
5216	}
5217
5218	QualType getSelectedType() const {
5219	assert(hasSelectedType() && "Type is dependant");
5220	return *(getExpansionsPtr() + *getSelectedIndex());
5221	}
5222
5223	std::optional<unsigned> getSelectedIndex() const;
5224
5225	bool hasSelectedType() const { return getSelectedIndex() != std::nullopt; }
5226
5227	ArrayRef<QualType> getExpansions() const {
5228	return {getExpansionsPtr(), Size};
5229	}
5230
5231	static bool classof(const Type *T) {
5232	return T->getTypeClass() == PackIndexing;
5233	}
5234
5235	void Profile(llvm::FoldingSetNodeID &ID) {
5236	if (hasSelectedType())
5237	getSelectedType().Profile(ID);
5238	else
5239	Profile(ID, Context, Pattern: getPattern(), E: getIndexExpr());
5240	}
5241	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
5242	QualType Pattern, Expr *E);
5243
5244	private:
5245	const QualType *getExpansionsPtr() const {
5246	return getTrailingObjects<QualType>();
5247	}
5248
5249	static TypeDependence computeDependence(QualType Pattern, Expr *IndexExpr,
5250	ArrayRef<QualType> Expansions = {});
5251
5252	unsigned numTrailingObjects(OverloadToken<QualType>) const { return Size; }
5253	};
5254
5255	/// A unary type transform, which is a type constructed from another.
5256	class UnaryTransformType : public Type {
5257	public:
5258	enum UTTKind {
5259	#define TRANSFORM_TYPE_TRAIT_DEF(Enum, _) Enum,
5260	#include "clang/Basic/TransformTypeTraits.def"
5261	};
5262
5263	private:
5264	/// The untransformed type.
5265	QualType BaseType;
5266
5267	/// The transformed type if not dependent, otherwise the same as BaseType.
5268	QualType UnderlyingType;
5269
5270	UTTKind UKind;
5271
5272	protected:
5273	friend class ASTContext;
5274
5275	UnaryTransformType(QualType BaseTy, QualType UnderlyingTy, UTTKind UKind,
5276	QualType CanonicalTy);
5277
5278	public:
5279	bool isSugared() const { return !isDependentType(); }
5280	QualType desugar() const { return UnderlyingType; }
5281
5282	QualType getUnderlyingType() const { return UnderlyingType; }
5283	QualType getBaseType() const { return BaseType; }
5284
5285	UTTKind getUTTKind() const { return UKind; }
5286
5287	static bool classof(const Type *T) {
5288	return T->getTypeClass() == UnaryTransform;
5289	}
5290	};
5291
5292	/// Internal representation of canonical, dependent
5293	/// __underlying_type(type) types.
5294	///
5295	/// This class is used internally by the ASTContext to manage
5296	/// canonical, dependent types, only. Clients will only see instances
5297	/// of this class via UnaryTransformType nodes.
5298	class DependentUnaryTransformType : public UnaryTransformType,
5299	public llvm::FoldingSetNode {
5300	public:
5301	DependentUnaryTransformType(const ASTContext &C, QualType BaseType,
5302	UTTKind UKind);
5303
5304	void Profile(llvm::FoldingSetNodeID &ID) {
5305	Profile(ID, getBaseType(), getUTTKind());
5306	}
5307
5308	static void Profile(llvm::FoldingSetNodeID &ID, QualType BaseType,
5309	UTTKind UKind) {
5310	ID.AddPointer(Ptr: BaseType.getAsOpaquePtr());
5311	ID.AddInteger(I: (unsigned)UKind);
5312	}
5313	};
5314
5315	class TagType : public Type {
5316	friend class ASTReader;
5317	template <class T> friend class serialization::AbstractTypeReader;
5318
5319	/// Stores the TagDecl associated with this type. The decl may point to any
5320	/// TagDecl that declares the entity.
5321	TagDecl *decl;
5322
5323	protected:
5324	TagType(TypeClass TC, const TagDecl *D, QualType can);
5325
5326	public:
5327	TagDecl *getDecl() const;
5328
5329	/// Determines whether this type is in the process of being defined.
5330	bool isBeingDefined() const;
5331
5332	static bool classof(const Type *T) {
5333	return T->getTypeClass() == Enum || T->getTypeClass() == Record;
5334	}
5335	};
5336
5337	/// A helper class that allows the use of isa/cast/dyncast
5338	/// to detect TagType objects of structs/unions/classes.
5339	class RecordType : public TagType {
5340	protected:
5341	friend class ASTContext; // ASTContext creates these.
5342
5343	explicit RecordType(const RecordDecl *D)
5344	: TagType(Record, reinterpret_cast<const TagDecl*>(D), QualType()) {}
5345	explicit RecordType(TypeClass TC, RecordDecl *D)
5346	: TagType(TC, reinterpret_cast<const TagDecl*>(D), QualType()) {}
5347
5348	public:
5349	RecordDecl *getDecl() const {
5350	return reinterpret_cast<RecordDecl*>(TagType::getDecl());
5351	}
5352
5353	/// Recursively check all fields in the record for const-ness. If any field
5354	/// is declared const, return true. Otherwise, return false.
5355	bool hasConstFields() const;
5356
5357	bool isSugared() const { return false; }
5358	QualType desugar() const { return QualType(this, 0); }
5359
5360	static bool classof(const Type *T) { return T->getTypeClass() == Record; }
5361	};
5362
5363	/// A helper class that allows the use of isa/cast/dyncast
5364	/// to detect TagType objects of enums.
5365	class EnumType : public TagType {
5366	friend class ASTContext; // ASTContext creates these.
5367
5368	explicit EnumType(const EnumDecl *D)
5369	: TagType(Enum, reinterpret_cast<const TagDecl*>(D), QualType()) {}
5370
5371	public:
5372	EnumDecl *getDecl() const {
5373	return reinterpret_cast<EnumDecl*>(TagType::getDecl());
5374	}
5375
5376	bool isSugared() const { return false; }
5377	QualType desugar() const { return QualType(this, 0); }
5378
5379	static bool classof(const Type *T) { return T->getTypeClass() == Enum; }
5380	};
5381
5382	/// An attributed type is a type to which a type attribute has been applied.
5383	///
5384	/// The "modified type" is the fully-sugared type to which the attributed
5385	/// type was applied; generally it is not canonically equivalent to the
5386	/// attributed type. The "equivalent type" is the minimally-desugared type
5387	/// which the type is canonically equivalent to.
5388	///
5389	/// For example, in the following attributed type:
5390	/// int32_t __attribute__((vector_size(16)))
5391	/// - the modified type is the TypedefType for int32_t
5392	/// - the equivalent type is VectorType(16, int32_t)
5393	/// - the canonical type is VectorType(16, int)
5394	class AttributedType : public Type, public llvm::FoldingSetNode {
5395	public:
5396	using Kind = attr::Kind;
5397
5398	private:
5399	friend class ASTContext; // ASTContext creates these
5400
5401	QualType ModifiedType;
5402	QualType EquivalentType;
5403
5404	AttributedType(QualType canon, attr::Kind attrKind, QualType modified,
5405	QualType equivalent)
5406	: Type(Attributed, canon, equivalent->getDependence()),
5407	ModifiedType(modified), EquivalentType(equivalent) {
5408	AttributedTypeBits.AttrKind = attrKind;
5409	}
5410
5411	public:
5412	Kind getAttrKind() const {
5413	return static_cast<Kind>(AttributedTypeBits.AttrKind);
5414	}
5415
5416	QualType getModifiedType() const { return ModifiedType; }
5417	QualType getEquivalentType() const { return EquivalentType; }
5418
5419	bool isSugared() const { return true; }
5420	QualType desugar() const { return getEquivalentType(); }
5421
5422	/// Does this attribute behave like a type qualifier?
5423	///
5424	/// A type qualifier adjusts a type to provide specialized rules for
5425	/// a specific object, like the standard const and volatile qualifiers.
5426	/// This includes attributes controlling things like nullability,
5427	/// address spaces, and ARC ownership. The value of the object is still
5428	/// largely described by the modified type.
5429	///
5430	/// In contrast, many type attributes "rewrite" their modified type to
5431	/// produce a fundamentally different type, not necessarily related in any
5432	/// formalizable way to the original type. For example, calling convention
5433	/// and vector attributes are not simple type qualifiers.
5434	///
5435	/// Type qualifiers are often, but not always, reflected in the canonical
5436	/// type.
5437	bool isQualifier() const;
5438
5439	bool isMSTypeSpec() const;
5440
5441	bool isWebAssemblyFuncrefSpec() const;
5442
5443	bool isCallingConv() const;
5444
5445	std::optional<NullabilityKind> getImmediateNullability() const;
5446
5447	/// Retrieve the attribute kind corresponding to the given
5448	/// nullability kind.
5449	static Kind getNullabilityAttrKind(NullabilityKind kind) {
5450	switch (kind) {
5451	case NullabilityKind::NonNull:
5452	return attr::TypeNonNull;
5453
5454	case NullabilityKind::Nullable:
5455	return attr::TypeNullable;
5456
5457	case NullabilityKind::NullableResult:
5458	return attr::TypeNullableResult;
5459
5460	case NullabilityKind::Unspecified:
5461	return attr::TypeNullUnspecified;
5462	}
5463	llvm_unreachable("Unknown nullability kind.");
5464	}
5465
5466	/// Strip off the top-level nullability annotation on the given
5467	/// type, if it's there.
5468	///
5469	/// \param T The type to strip. If the type is exactly an
5470	/// AttributedType specifying nullability (without looking through
5471	/// type sugar), the nullability is returned and this type changed
5472	/// to the underlying modified type.
5473	///
5474	/// \returns the top-level nullability, if present.
5475	static std::optional<NullabilityKind> stripOuterNullability(QualType &T);
5476
5477	void Profile(llvm::FoldingSetNodeID &ID) {
5478	Profile(ID, getAttrKind(), ModifiedType, EquivalentType);
5479	}
5480
5481	static void Profile(llvm::FoldingSetNodeID &ID, Kind attrKind,
5482	QualType modified, QualType equivalent) {
5483	ID.AddInteger(I: attrKind);
5484	ID.AddPointer(Ptr: modified.getAsOpaquePtr());
5485	ID.AddPointer(Ptr: equivalent.getAsOpaquePtr());
5486	}
5487
5488	static bool classof(const Type *T) {
5489	return T->getTypeClass() == Attributed;
5490	}
5491	};
5492
5493	class BTFTagAttributedType : public Type, public llvm::FoldingSetNode {
5494	private:
5495	friend class ASTContext; // ASTContext creates these
5496
5497	QualType WrappedType;
5498	const BTFTypeTagAttr *BTFAttr;
5499
5500	BTFTagAttributedType(QualType Canon, QualType Wrapped,
5501	const BTFTypeTagAttr *BTFAttr)
5502	: Type(BTFTagAttributed, Canon, Wrapped->getDependence()),
5503	WrappedType(Wrapped), BTFAttr(BTFAttr) {}
5504
5505	public:
5506	QualType getWrappedType() const { return WrappedType; }
5507	const BTFTypeTagAttr *getAttr() const { return BTFAttr; }
5508
5509	bool isSugared() const { return true; }
5510	QualType desugar() const { return getWrappedType(); }
5511
5512	void Profile(llvm::FoldingSetNodeID &ID) {
5513	Profile(ID, WrappedType, BTFAttr);
5514	}
5515
5516	static void Profile(llvm::FoldingSetNodeID &ID, QualType Wrapped,
5517	const BTFTypeTagAttr *BTFAttr) {
5518	ID.AddPointer(Ptr: Wrapped.getAsOpaquePtr());
5519	ID.AddPointer(Ptr: BTFAttr);
5520	}
5521
5522	static bool classof(const Type *T) {
5523	return T->getTypeClass() == BTFTagAttributed;
5524	}
5525	};
5526
5527	class TemplateTypeParmType : public Type, public llvm::FoldingSetNode {
5528	friend class ASTContext; // ASTContext creates these
5529
5530	// Helper data collector for canonical types.
5531	struct CanonicalTTPTInfo {
5532	unsigned Depth : 15;
5533	unsigned ParameterPack : 1;
5534	unsigned Index : 16;
5535	};
5536
5537	union {
5538	// Info for the canonical type.
5539	CanonicalTTPTInfo CanTTPTInfo;
5540
5541	// Info for the non-canonical type.
5542	TemplateTypeParmDecl *TTPDecl;
5543	};
5544
5545	/// Build a non-canonical type.
5546	TemplateTypeParmType(TemplateTypeParmDecl *TTPDecl, QualType Canon)
5547	: Type(TemplateTypeParm, Canon,
5548	TypeDependence::DependentInstantiation |
5549	(Canon->getDependence() & TypeDependence::UnexpandedPack)),
5550	TTPDecl(TTPDecl) {}
5551
5552	/// Build the canonical type.
5553	TemplateTypeParmType(unsigned D, unsigned I, bool PP)
5554	: Type(TemplateTypeParm, QualType(this, 0),
5555	TypeDependence::DependentInstantiation |
5556	(PP ? TypeDependence::UnexpandedPack : TypeDependence::None)) {
5557	CanTTPTInfo.Depth = D;
5558	CanTTPTInfo.Index = I;
5559	CanTTPTInfo.ParameterPack = PP;
5560	}
5561
5562	const CanonicalTTPTInfo& getCanTTPTInfo() const {
5563	QualType Can = getCanonicalTypeInternal();
5564	return Can->castAs<TemplateTypeParmType>()->CanTTPTInfo;
5565	}
5566
5567	public:
5568	unsigned getDepth() const { return getCanTTPTInfo().Depth; }
5569	unsigned getIndex() const { return getCanTTPTInfo().Index; }
5570	bool isParameterPack() const { return getCanTTPTInfo().ParameterPack; }
5571
5572	TemplateTypeParmDecl *getDecl() const {
5573	return isCanonicalUnqualified() ? nullptr : TTPDecl;
5574	}
5575
5576	IdentifierInfo *getIdentifier() const;
5577
5578	bool isSugared() const { return false; }
5579	QualType desugar() const { return QualType(this, 0); }
5580
5581	void Profile(llvm::FoldingSetNodeID &ID) {
5582	Profile(ID, Depth: getDepth(), Index: getIndex(), ParameterPack: isParameterPack(), TTPDecl: getDecl());
5583	}
5584
5585	static void Profile(llvm::FoldingSetNodeID &ID, unsigned Depth,
5586	unsigned Index, bool ParameterPack,
5587	TemplateTypeParmDecl *TTPDecl) {
5588	ID.AddInteger(I: Depth);
5589	ID.AddInteger(I: Index);
5590	ID.AddBoolean(B: ParameterPack);
5591	ID.AddPointer(Ptr: TTPDecl);
5592	}
5593
5594	static bool classof(const Type *T) {
5595	return T->getTypeClass() == TemplateTypeParm;
5596	}
5597	};
5598
5599	/// Represents the result of substituting a type for a template
5600	/// type parameter.
5601	///
5602	/// Within an instantiated template, all template type parameters have
5603	/// been replaced with these. They are used solely to record that a
5604	/// type was originally written as a template type parameter;
5605	/// therefore they are never canonical.
5606	class SubstTemplateTypeParmType final
5607	: public Type,
5608	public llvm::FoldingSetNode,
5609	private llvm::TrailingObjects<SubstTemplateTypeParmType, QualType> {
5610	friend class ASTContext;
5611	friend class llvm::TrailingObjects<SubstTemplateTypeParmType, QualType>;
5612
5613	Decl *AssociatedDecl;
5614
5615	SubstTemplateTypeParmType(QualType Replacement, Decl *AssociatedDecl,
5616	unsigned Index, std::optional<unsigned> PackIndex);
5617
5618	public:
5619	/// Gets the type that was substituted for the template
5620	/// parameter.
5621	QualType getReplacementType() const {
5622	return SubstTemplateTypeParmTypeBits.HasNonCanonicalUnderlyingType
5623	? *getTrailingObjects<QualType>()
5624	: getCanonicalTypeInternal();
5625	}
5626
5627	/// A template-like entity which owns the whole pattern being substituted.
5628	/// This will usually own a set of template parameters, or in some
5629	/// cases might even be a template parameter itself.
5630	Decl *getAssociatedDecl() const { return AssociatedDecl; }
5631
5632	/// Gets the template parameter declaration that was substituted for.
5633	const TemplateTypeParmDecl *getReplacedParameter() const;
5634
5635	/// Returns the index of the replaced parameter in the associated declaration.
5636	/// This should match the result of `getReplacedParameter()->getIndex()`.
5637	unsigned getIndex() const { return SubstTemplateTypeParmTypeBits.Index; }
5638
5639	std::optional<unsigned> getPackIndex() const {
5640	if (SubstTemplateTypeParmTypeBits.PackIndex == 0)
5641	return std::nullopt;
5642	return SubstTemplateTypeParmTypeBits.PackIndex - 1;
5643	}
5644
5645	bool isSugared() const { return true; }
5646	QualType desugar() const { return getReplacementType(); }
5647
5648	void Profile(llvm::FoldingSetNodeID &ID) {
5649	Profile(ID, Replacement: getReplacementType(), AssociatedDecl: getAssociatedDecl(), Index: getIndex(),
5650	PackIndex: getPackIndex());
5651	}
5652
5653	static void Profile(llvm::FoldingSetNodeID &ID, QualType Replacement,
5654	const Decl *AssociatedDecl, unsigned Index,
5655	std::optional<unsigned> PackIndex) {
5656	Replacement.Profile(ID);
5657	ID.AddPointer(Ptr: AssociatedDecl);
5658	ID.AddInteger(I: Index);
5659	ID.AddInteger(I: PackIndex ? *PackIndex - 1 : 0);
5660	}
5661
5662	static bool classof(const Type *T) {
5663	return T->getTypeClass() == SubstTemplateTypeParm;
5664	}
5665	};
5666
5667	/// Represents the result of substituting a set of types for a template
5668	/// type parameter pack.
5669	///
5670	/// When a pack expansion in the source code contains multiple parameter packs
5671	/// and those parameter packs correspond to different levels of template
5672	/// parameter lists, this type node is used to represent a template type
5673	/// parameter pack from an outer level, which has already had its argument pack
5674	/// substituted but that still lives within a pack expansion that itself
5675	/// could not be instantiated. When actually performing a substitution into
5676	/// that pack expansion (e.g., when all template parameters have corresponding
5677	/// arguments), this type will be replaced with the \c SubstTemplateTypeParmType
5678	/// at the current pack substitution index.
5679	class SubstTemplateTypeParmPackType : public Type, public llvm::FoldingSetNode {
5680	friend class ASTContext;
5681
5682	/// A pointer to the set of template arguments that this
5683	/// parameter pack is instantiated with.
5684	const TemplateArgument *Arguments;
5685
5686	llvm::PointerIntPair<Decl *, 1, bool> AssociatedDeclAndFinal;
5687
5688	SubstTemplateTypeParmPackType(QualType Canon, Decl *AssociatedDecl,
5689	unsigned Index, bool Final,
5690	const TemplateArgument &ArgPack);
5691
5692	public:
5693	IdentifierInfo *getIdentifier() const;
5694
5695	/// A template-like entity which owns the whole pattern being substituted.
5696	/// This will usually own a set of template parameters, or in some
5697	/// cases might even be a template parameter itself.
5698	Decl *getAssociatedDecl() const;
5699
5700	/// Gets the template parameter declaration that was substituted for.
5701	const TemplateTypeParmDecl *getReplacedParameter() const;
5702
5703	/// Returns the index of the replaced parameter in the associated declaration.
5704	/// This should match the result of `getReplacedParameter()->getIndex()`.
5705	unsigned getIndex() const { return SubstTemplateTypeParmPackTypeBits.Index; }
5706
5707	// When true the substitution will be 'Final' (subst node won't be placed).
5708	bool getFinal() const;
5709
5710	unsigned getNumArgs() const {
5711	return SubstTemplateTypeParmPackTypeBits.NumArgs;
5712	}
5713
5714	bool isSugared() const { return false; }
5715	QualType desugar() const { return QualType(this, 0); }
5716
5717	TemplateArgument getArgumentPack() const;
5718
5719	void Profile(llvm::FoldingSetNodeID &ID);
5720	static void Profile(llvm::FoldingSetNodeID &ID, const Decl *AssociatedDecl,
5721	unsigned Index, bool Final,
5722	const TemplateArgument &ArgPack);
5723
5724	static bool classof(const Type *T) {
5725	return T->getTypeClass() == SubstTemplateTypeParmPack;
5726	}
5727	};
5728
5729	/// Common base class for placeholders for types that get replaced by
5730	/// placeholder type deduction: C++11 auto, C++14 decltype(auto), C++17 deduced
5731	/// class template types, and constrained type names.
5732	///
5733	/// These types are usually a placeholder for a deduced type. However, before
5734	/// the initializer is attached, or (usually) if the initializer is
5735	/// type-dependent, there is no deduced type and the type is canonical. In
5736	/// the latter case, it is also a dependent type.
5737	class DeducedType : public Type {
5738	QualType DeducedAsType;
5739
5740	protected:
5741	DeducedType(TypeClass TC, QualType DeducedAsType,
5742	TypeDependence ExtraDependence, QualType Canon)
5743	: Type(TC, Canon,
5744	ExtraDependence | (DeducedAsType.isNull()
5745	? TypeDependence::None
5746	: DeducedAsType->getDependence() &
5747	~TypeDependence::VariablyModified)),
5748	DeducedAsType(DeducedAsType) {}
5749
5750	public:
5751	bool isSugared() const { return !DeducedAsType.isNull(); }
5752	QualType desugar() const {
5753	return isSugared() ? DeducedAsType : QualType(this, 0);
5754	}
5755
5756	/// Get the type deduced for this placeholder type, or null if it
5757	/// has not been deduced.
5758	QualType getDeducedType() const { return DeducedAsType; }
5759	bool isDeduced() const {
5760	return !DeducedAsType.isNull() || isDependentType();
5761	}
5762
5763	static bool classof(const Type *T) {
5764	return T->getTypeClass() == Auto ||
5765	T->getTypeClass() == DeducedTemplateSpecialization;
5766	}
5767	};
5768
5769	/// Represents a C++11 auto or C++14 decltype(auto) type, possibly constrained
5770	/// by a type-constraint.
5771	class AutoType : public DeducedType, public llvm::FoldingSetNode {
5772	friend class ASTContext; // ASTContext creates these
5773
5774	ConceptDecl *TypeConstraintConcept;
5775
5776	AutoType(QualType DeducedAsType, AutoTypeKeyword Keyword,
5777	TypeDependence ExtraDependence, QualType Canon, ConceptDecl *CD,
5778	ArrayRef<TemplateArgument> TypeConstraintArgs);
5779
5780	public:
5781	ArrayRef<TemplateArgument> getTypeConstraintArguments() const {
5782	return {reinterpret_cast<const TemplateArgument *>(this + 1),
5783	AutoTypeBits.NumArgs};
5784	}
5785
5786	ConceptDecl *getTypeConstraintConcept() const {
5787	return TypeConstraintConcept;
5788	}
5789
5790	bool isConstrained() const {
5791	return TypeConstraintConcept != nullptr;
5792	}
5793
5794	bool isDecltypeAuto() const {
5795	return getKeyword() == AutoTypeKeyword::DecltypeAuto;
5796	}
5797
5798	bool isGNUAutoType() const {
5799	return getKeyword() == AutoTypeKeyword::GNUAutoType;
5800	}
5801
5802	AutoTypeKeyword getKeyword() const {
5803	return (AutoTypeKeyword)AutoTypeBits.Keyword;
5804	}
5805
5806	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context);
5807	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
5808	QualType Deduced, AutoTypeKeyword Keyword,
5809	bool IsDependent, ConceptDecl *CD,
5810	ArrayRef<TemplateArgument> Arguments);
5811
5812	static bool classof(const Type *T) {
5813	return T->getTypeClass() == Auto;
5814	}
5815	};
5816
5817	/// Represents a C++17 deduced template specialization type.
5818	class DeducedTemplateSpecializationType : public DeducedType,
5819	public llvm::FoldingSetNode {
5820	friend class ASTContext; // ASTContext creates these
5821
5822	/// The name of the template whose arguments will be deduced.
5823	TemplateName Template;
5824
5825	DeducedTemplateSpecializationType(TemplateName Template,
5826	QualType DeducedAsType,
5827	bool IsDeducedAsDependent)
5828	: DeducedType(DeducedTemplateSpecialization, DeducedAsType,
5829	toTypeDependence(Template.getDependence()) |
5830	(IsDeducedAsDependent
5831	? TypeDependence::DependentInstantiation
5832	: TypeDependence::None),
5833	DeducedAsType.isNull() ? QualType(this, 0)
5834	: DeducedAsType.getCanonicalType()),
5835	Template(Template) {}
5836
5837	public:
5838	/// Retrieve the name of the template that we are deducing.
5839	TemplateName getTemplateName() const { return Template;}
5840
5841	void Profile(llvm::FoldingSetNodeID &ID) {
5842	Profile(ID, getTemplateName(), getDeducedType(), isDependentType());
5843	}
5844
5845	static void Profile(llvm::FoldingSetNodeID &ID, TemplateName Template,
5846	QualType Deduced, bool IsDependent) {
5847	Template.Profile(ID);
5848	QualType CanonicalType =
5849	Deduced.isNull() ? Deduced : Deduced.getCanonicalType();
5850	ID.AddPointer(Ptr: CanonicalType.getAsOpaquePtr());
5851	ID.AddBoolean(B: IsDependent || Template.isDependent());
5852	}
5853
5854	static bool classof(const Type *T) {
5855	return T->getTypeClass() == DeducedTemplateSpecialization;
5856	}
5857	};
5858
5859	/// Represents a type template specialization; the template
5860	/// must be a class template, a type alias template, or a template
5861	/// template parameter. A template which cannot be resolved to one of
5862	/// these, e.g. because it is written with a dependent scope
5863	/// specifier, is instead represented as a
5864	/// @c DependentTemplateSpecializationType.
5865	///
5866	/// A non-dependent template specialization type is always "sugar",
5867	/// typically for a \c RecordType. For example, a class template
5868	/// specialization type of \c vector<int> will refer to a tag type for
5869	/// the instantiation \c std::vector<int, std::allocator<int>>
5870	///
5871	/// Template specializations are dependent if either the template or
5872	/// any of the template arguments are dependent, in which case the
5873	/// type may also be canonical.
5874	///
5875	/// Instances of this type are allocated with a trailing array of
5876	/// TemplateArguments, followed by a QualType representing the
5877	/// non-canonical aliased type when the template is a type alias
5878	/// template.
5879	class TemplateSpecializationType : public Type, public llvm::FoldingSetNode {
5880	friend class ASTContext; // ASTContext creates these
5881
5882	/// The name of the template being specialized. This is
5883	/// either a TemplateName::Template (in which case it is a
5884	/// ClassTemplateDecl*, a TemplateTemplateParmDecl*, or a
5885	/// TypeAliasTemplateDecl*), a
5886	/// TemplateName::SubstTemplateTemplateParmPack, or a
5887	/// TemplateName::SubstTemplateTemplateParm (in which case the
5888	/// replacement must, recursively, be one of these).
5889	TemplateName Template;
5890
5891	TemplateSpecializationType(TemplateName T,
5892	ArrayRef<TemplateArgument> Args,
5893	QualType Canon,
5894	QualType Aliased);
5895
5896	public:
5897	/// Determine whether any of the given template arguments are dependent.
5898	///
5899	/// The converted arguments should be supplied when known; whether an
5900	/// argument is dependent can depend on the conversions performed on it
5901	/// (for example, a 'const int' passed as a template argument might be
5902	/// dependent if the parameter is a reference but non-dependent if the
5903	/// parameter is an int).
5904	///
5905	/// Note that the \p Args parameter is unused: this is intentional, to remind
5906	/// the caller that they need to pass in the converted arguments, not the
5907	/// specified arguments.
5908	static bool
5909	anyDependentTemplateArguments(ArrayRef<TemplateArgumentLoc> Args,
5910	ArrayRef<TemplateArgument> Converted);
5911	static bool
5912	anyDependentTemplateArguments(const TemplateArgumentListInfo &,
5913	ArrayRef<TemplateArgument> Converted);
5914	static bool anyInstantiationDependentTemplateArguments(
5915	ArrayRef<TemplateArgumentLoc> Args);
5916
5917	/// True if this template specialization type matches a current
5918	/// instantiation in the context in which it is found.
5919	bool isCurrentInstantiation() const {
5920	return isa<InjectedClassNameType>(getCanonicalTypeInternal());
5921	}
5922
5923	/// Determine if this template specialization type is for a type alias
5924	/// template that has been substituted.
5925	///
5926	/// Nearly every template specialization type whose template is an alias
5927	/// template will be substituted. However, this is not the case when
5928	/// the specialization contains a pack expansion but the template alias
5929	/// does not have a corresponding parameter pack, e.g.,
5930	///
5931	/// \code
5932	/// template<typename T, typename U, typename V> struct S;
5933	/// template<typename T, typename U> using A = S<T, int, U>;
5934	/// template<typename... Ts> struct X {
5935	/// typedef A<Ts...> type; // not a type alias
5936	/// };
5937	/// \endcode
5938	bool isTypeAlias() const { return TemplateSpecializationTypeBits.TypeAlias; }
5939
5940	/// Get the aliased type, if this is a specialization of a type alias
5941	/// template.
5942	QualType getAliasedType() const;
5943
5944	/// Retrieve the name of the template that we are specializing.
5945	TemplateName getTemplateName() const { return Template; }
5946
5947	ArrayRef<TemplateArgument> template_arguments() const {
5948	return {reinterpret_cast<const TemplateArgument *>(this + 1),
5949	TemplateSpecializationTypeBits.NumArgs};
5950	}
5951
5952	bool isSugared() const {
5953	return !isDependentType() || isCurrentInstantiation() || isTypeAlias();
5954	}
5955
5956	QualType desugar() const {
5957	return isTypeAlias() ? getAliasedType() : getCanonicalTypeInternal();
5958	}
5959
5960	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx);
5961	static void Profile(llvm::FoldingSetNodeID &ID, TemplateName T,
5962	ArrayRef<TemplateArgument> Args,
5963	const ASTContext &Context);
5964
5965	static bool classof(const Type *T) {
5966	return T->getTypeClass() == TemplateSpecialization;
5967	}
5968	};
5969
5970	/// Print a template argument list, including the '<' and '>'
5971	/// enclosing the template arguments.
5972	void printTemplateArgumentList(raw_ostream &OS,
5973	ArrayRef<TemplateArgument> Args,
5974	const PrintingPolicy &Policy,
5975	const TemplateParameterList *TPL = nullptr);
5976
5977	void printTemplateArgumentList(raw_ostream &OS,
5978	ArrayRef<TemplateArgumentLoc> Args,
5979	const PrintingPolicy &Policy,
5980	const TemplateParameterList *TPL = nullptr);
5981
5982	void printTemplateArgumentList(raw_ostream &OS,
5983	const TemplateArgumentListInfo &Args,
5984	const PrintingPolicy &Policy,
5985	const TemplateParameterList *TPL = nullptr);
5986
5987	/// Make a best-effort determination of whether the type T can be produced by
5988	/// substituting Args into the default argument of Param.
5989	bool isSubstitutedDefaultArgument(ASTContext &Ctx, TemplateArgument Arg,
5990	const NamedDecl *Param,
5991	ArrayRef<TemplateArgument> Args,
5992	unsigned Depth);
5993
5994	/// The injected class name of a C++ class template or class
5995	/// template partial specialization. Used to record that a type was
5996	/// spelled with a bare identifier rather than as a template-id; the
5997	/// equivalent for non-templated classes is just RecordType.
5998	///
5999	/// Injected class name types are always dependent. Template
6000	/// instantiation turns these into RecordTypes.
6001	///
6002	/// Injected class name types are always canonical. This works
6003	/// because it is impossible to compare an injected class name type
6004	/// with the corresponding non-injected template type, for the same
6005	/// reason that it is impossible to directly compare template
6006	/// parameters from different dependent contexts: injected class name
6007	/// types can only occur within the scope of a particular templated
6008	/// declaration, and within that scope every template specialization
6009	/// will canonicalize to the injected class name (when appropriate
6010	/// according to the rules of the language).
6011	class InjectedClassNameType : public Type {
6012	friend class ASTContext; // ASTContext creates these.
6013	friend class ASTNodeImporter;
6014	friend class ASTReader; // FIXME: ASTContext::getInjectedClassNameType is not
6015	// currently suitable for AST reading, too much
6016	// interdependencies.
6017	template <class T> friend class serialization::AbstractTypeReader;
6018
6019	CXXRecordDecl *Decl;
6020
6021	/// The template specialization which this type represents.
6022	/// For example, in
6023	/// template <class T> class A { ... };
6024	/// this is A<T>, whereas in
6025	/// template <class X, class Y> class A<B<X,Y> > { ... };
6026	/// this is A<B<X,Y> >.
6027	///
6028	/// It is always unqualified, always a template specialization type,
6029	/// and always dependent.
6030	QualType InjectedType;
6031
6032	InjectedClassNameType(CXXRecordDecl *D, QualType TST)
6033	: Type(InjectedClassName, QualType(),
6034	TypeDependence::DependentInstantiation),
6035	Decl(D), InjectedType(TST) {
6036	assert(isa<TemplateSpecializationType>(TST));
6037	assert(!TST.hasQualifiers());
6038	assert(TST->isDependentType());
6039	}
6040
6041	public:
6042	QualType getInjectedSpecializationType() const { return InjectedType; }
6043
6044	const TemplateSpecializationType *getInjectedTST() const {
6045	return cast<TemplateSpecializationType>(InjectedType.getTypePtr());
6046	}
6047
6048	TemplateName getTemplateName() const {
6049	return getInjectedTST()->getTemplateName();
6050	}
6051
6052	CXXRecordDecl *getDecl() const;
6053
6054	bool isSugared() const { return false; }
6055	QualType desugar() const { return QualType(this, 0); }
6056
6057	static bool classof(const Type *T) {
6058	return T->getTypeClass() == InjectedClassName;
6059	}
6060	};
6061
6062	/// The elaboration keyword that precedes a qualified type name or
6063	/// introduces an elaborated-type-specifier.
6064	enum class ElaboratedTypeKeyword {
6065	/// The "struct" keyword introduces the elaborated-type-specifier.
6066	Struct,
6067
6068	/// The "__interface" keyword introduces the elaborated-type-specifier.
6069	Interface,
6070
6071	/// The "union" keyword introduces the elaborated-type-specifier.
6072	Union,
6073
6074	/// The "class" keyword introduces the elaborated-type-specifier.
6075	Class,
6076
6077	/// The "enum" keyword introduces the elaborated-type-specifier.
6078	Enum,
6079
6080	/// The "typename" keyword precedes the qualified type name, e.g.,
6081	/// \c typename T::type.
6082	Typename,
6083
6084	/// No keyword precedes the qualified type name.
6085	None
6086	};
6087
6088	/// The kind of a tag type.
6089	enum class TagTypeKind {
6090	/// The "struct" keyword.
6091	Struct,
6092
6093	/// The "__interface" keyword.
6094	Interface,
6095
6096	/// The "union" keyword.
6097	Union,
6098
6099	/// The "class" keyword.
6100	Class,
6101
6102	/// The "enum" keyword.
6103	Enum
6104	};
6105
6106	/// A helper class for Type nodes having an ElaboratedTypeKeyword.
6107	/// The keyword in stored in the free bits of the base class.
6108	/// Also provides a few static helpers for converting and printing
6109	/// elaborated type keyword and tag type kind enumerations.
6110	class TypeWithKeyword : public Type {
6111	protected:
6112	TypeWithKeyword(ElaboratedTypeKeyword Keyword, TypeClass tc,
6113	QualType Canonical, TypeDependence Dependence)
6114	: Type(tc, Canonical, Dependence) {
6115	TypeWithKeywordBits.Keyword = llvm::to_underlying(Keyword);
6116	}
6117
6118	public:
6119	ElaboratedTypeKeyword getKeyword() const {
6120	return static_cast<ElaboratedTypeKeyword>(TypeWithKeywordBits.Keyword);
6121	}
6122
6123	/// Converts a type specifier (DeclSpec::TST) into an elaborated type keyword.
6124	static ElaboratedTypeKeyword getKeywordForTypeSpec(unsigned TypeSpec);
6125
6126	/// Converts a type specifier (DeclSpec::TST) into a tag type kind.
6127	/// It is an error to provide a type specifier which *isn't* a tag kind here.
6128	static TagTypeKind getTagTypeKindForTypeSpec(unsigned TypeSpec);
6129
6130	/// Converts a TagTypeKind into an elaborated type keyword.
6131	static ElaboratedTypeKeyword getKeywordForTagTypeKind(TagTypeKind Tag);
6132
6133	/// Converts an elaborated type keyword into a TagTypeKind.
6134	/// It is an error to provide an elaborated type keyword
6135	/// which *isn't* a tag kind here.
6136	static TagTypeKind getTagTypeKindForKeyword(ElaboratedTypeKeyword Keyword);
6137
6138	static bool KeywordIsTagTypeKind(ElaboratedTypeKeyword Keyword);
6139
6140	static StringRef getKeywordName(ElaboratedTypeKeyword Keyword);
6141
6142	static StringRef getTagTypeKindName(TagTypeKind Kind) {
6143	return getKeywordName(Keyword: getKeywordForTagTypeKind(Tag: Kind));
6144	}
6145
6146	class CannotCastToThisType {};
6147	static CannotCastToThisType classof(const Type *);
6148	};
6149
6150	/// Represents a type that was referred to using an elaborated type
6151	/// keyword, e.g., struct S, or via a qualified name, e.g., N::M::type,
6152	/// or both.
6153	///
6154	/// This type is used to keep track of a type name as written in the
6155	/// source code, including tag keywords and any nested-name-specifiers.
6156	/// The type itself is always "sugar", used to express what was written
6157	/// in the source code but containing no additional semantic information.
6158	class ElaboratedType final
6159	: public TypeWithKeyword,
6160	public llvm::FoldingSetNode,
6161	private llvm::TrailingObjects<ElaboratedType, TagDecl *> {
6162	friend class ASTContext; // ASTContext creates these
6163	friend TrailingObjects;
6164
6165	/// The nested name specifier containing the qualifier.
6166	NestedNameSpecifier *NNS;
6167
6168	/// The type that this qualified name refers to.
6169	QualType NamedType;
6170
6171	/// The (re)declaration of this tag type owned by this occurrence is stored
6172	/// as a trailing object if there is one. Use getOwnedTagDecl to obtain
6173	/// it, or obtain a null pointer if there is none.
6174
6175	ElaboratedType(ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
6176	QualType NamedType, QualType CanonType, TagDecl *OwnedTagDecl)
6177	: TypeWithKeyword(Keyword, Elaborated, CanonType,
6178	// Any semantic dependence on the qualifier will have
6179	// been incorporated into NamedType. We still need to
6180	// track syntactic (instantiation / error / pack)
6181	// dependence on the qualifier.
6182	NamedType->getDependence() |
6183	(NNS ? toSyntacticDependence(
6184	toTypeDependence(NNS->getDependence()))
6185	: TypeDependence::None)),
6186	NNS(NNS), NamedType(NamedType) {
6187	ElaboratedTypeBits.HasOwnedTagDecl = false;
6188	if (OwnedTagDecl) {
6189	ElaboratedTypeBits.HasOwnedTagDecl = true;
6190	*getTrailingObjects<TagDecl *>() = OwnedTagDecl;
6191	}
6192	}
6193
6194	public:
6195	/// Retrieve the qualification on this type.
6196	NestedNameSpecifier *getQualifier() const { return NNS; }
6197
6198	/// Retrieve the type named by the qualified-id.
6199	QualType getNamedType() const { return NamedType; }
6200
6201	/// Remove a single level of sugar.
6202	QualType desugar() const { return getNamedType(); }
6203
6204	/// Returns whether this type directly provides sugar.
6205	bool isSugared() const { return true; }
6206
6207	/// Return the (re)declaration of this type owned by this occurrence of this
6208	/// type, or nullptr if there is none.
6209	TagDecl *getOwnedTagDecl() const {
6210	return ElaboratedTypeBits.HasOwnedTagDecl ? *getTrailingObjects<TagDecl *>()
6211	: nullptr;
6212	}
6213
6214	void Profile(llvm::FoldingSetNodeID &ID) {
6215	Profile(ID, getKeyword(), NNS, NamedType, getOwnedTagDecl());
6216	}
6217
6218	static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
6219	NestedNameSpecifier *NNS, QualType NamedType,
6220	TagDecl *OwnedTagDecl) {
6221	ID.AddInteger(llvm::to_underlying(Keyword));
6222	ID.AddPointer(Ptr: NNS);
6223	NamedType.Profile(ID);
6224	ID.AddPointer(Ptr: OwnedTagDecl);
6225	}
6226
6227	static bool classof(const Type *T) { return T->getTypeClass() == Elaborated; }
6228	};
6229
6230	/// Represents a qualified type name for which the type name is
6231	/// dependent.
6232	///
6233	/// DependentNameType represents a class of dependent types that involve a
6234	/// possibly dependent nested-name-specifier (e.g., "T::") followed by a
6235	/// name of a type. The DependentNameType may start with a "typename" (for a
6236	/// typename-specifier), "class", "struct", "union", or "enum" (for a
6237	/// dependent elaborated-type-specifier), or nothing (in contexts where we
6238	/// know that we must be referring to a type, e.g., in a base class specifier).
6239	/// Typically the nested-name-specifier is dependent, but in MSVC compatibility
6240	/// mode, this type is used with non-dependent names to delay name lookup until
6241	/// instantiation.
6242	class DependentNameType : public TypeWithKeyword, public llvm::FoldingSetNode {
6243	friend class ASTContext; // ASTContext creates these
6244
6245	/// The nested name specifier containing the qualifier.
6246	NestedNameSpecifier *NNS;
6247
6248	/// The type that this typename specifier refers to.
6249	const IdentifierInfo *Name;
6250
6251	DependentNameType(ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
6252	const IdentifierInfo *Name, QualType CanonType)
6253	: TypeWithKeyword(Keyword, DependentName, CanonType,
6254	TypeDependence::DependentInstantiation |
6255	toTypeDependence(NNS->getDependence())),
6256	NNS(NNS), Name(Name) {}
6257
6258	public:
6259	/// Retrieve the qualification on this type.
6260	NestedNameSpecifier *getQualifier() const { return NNS; }
6261
6262	/// Retrieve the type named by the typename specifier as an identifier.
6263	///
6264	/// This routine will return a non-NULL identifier pointer when the
6265	/// form of the original typename was terminated by an identifier,
6266	/// e.g., "typename T::type".
6267	const IdentifierInfo *getIdentifier() const {
6268	return Name;
6269	}
6270
6271	bool isSugared() const { return false; }
6272	QualType desugar() const { return QualType(this, 0); }
6273
6274	void Profile(llvm::FoldingSetNodeID &ID) {
6275	Profile(ID, getKeyword(), NNS, Name);
6276	}
6277
6278	static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
6279	NestedNameSpecifier *NNS, const IdentifierInfo *Name) {
6280	ID.AddInteger(llvm::to_underlying(Keyword));
6281	ID.AddPointer(Ptr: NNS);
6282	ID.AddPointer(Ptr: Name);
6283	}
6284
6285	static bool classof(const Type *T) {
6286	return T->getTypeClass() == DependentName;
6287	}
6288	};
6289
6290	/// Represents a template specialization type whose template cannot be
6291	/// resolved, e.g.
6292	/// A<T>::template B<T>
6293	class DependentTemplateSpecializationType : public TypeWithKeyword,
6294	public llvm::FoldingSetNode {
6295	friend class ASTContext; // ASTContext creates these
6296
6297	/// The nested name specifier containing the qualifier.
6298	NestedNameSpecifier *NNS;
6299
6300	/// The identifier of the template.
6301	const IdentifierInfo *Name;
6302
6303	DependentTemplateSpecializationType(ElaboratedTypeKeyword Keyword,
6304	NestedNameSpecifier *NNS,
6305	const IdentifierInfo *Name,
6306	ArrayRef<TemplateArgument> Args,
6307	QualType Canon);
6308
6309	public:
6310	NestedNameSpecifier *getQualifier() const { return NNS; }
6311	const IdentifierInfo *getIdentifier() const { return Name; }
6312
6313	ArrayRef<TemplateArgument> template_arguments() const {
6314	return {reinterpret_cast<const TemplateArgument *>(this + 1),
6315	DependentTemplateSpecializationTypeBits.NumArgs};
6316	}
6317
6318	bool isSugared() const { return false; }
6319	QualType desugar() const { return QualType(this, 0); }
6320
6321	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
6322	Profile(ID, Context, getKeyword(), NNS, Name, template_arguments());
6323	}
6324
6325	static void Profile(llvm::FoldingSetNodeID &ID,
6326	const ASTContext &Context,
6327	ElaboratedTypeKeyword Keyword,
6328	NestedNameSpecifier *Qualifier,
6329	const IdentifierInfo *Name,
6330	ArrayRef<TemplateArgument> Args);
6331
6332	static bool classof(const Type *T) {
6333	return T->getTypeClass() == DependentTemplateSpecialization;
6334	}
6335	};
6336
6337	/// Represents a pack expansion of types.
6338	///
6339	/// Pack expansions are part of C++11 variadic templates. A pack
6340	/// expansion contains a pattern, which itself contains one or more
6341	/// "unexpanded" parameter packs. When instantiated, a pack expansion
6342	/// produces a series of types, each instantiated from the pattern of
6343	/// the expansion, where the Ith instantiation of the pattern uses the
6344	/// Ith arguments bound to each of the unexpanded parameter packs. The
6345	/// pack expansion is considered to "expand" these unexpanded
6346	/// parameter packs.
6347	///
6348	/// \code
6349	/// template<typename ...Types> struct tuple;
6350	///
6351	/// template<typename ...Types>
6352	/// struct tuple_of_references {
6353	/// typedef tuple<Types&...> type;
6354	/// };
6355	/// \endcode
6356	///
6357	/// Here, the pack expansion \c Types&... is represented via a
6358	/// PackExpansionType whose pattern is Types&.
6359	class PackExpansionType : public Type, public llvm::FoldingSetNode {
6360	friend class ASTContext; // ASTContext creates these
6361
6362	/// The pattern of the pack expansion.
6363	QualType Pattern;
6364
6365	PackExpansionType(QualType Pattern, QualType Canon,
6366	std::optional<unsigned> NumExpansions)
6367	: Type(PackExpansion, Canon,
6368	(Pattern->getDependence() | TypeDependence::Dependent |
6369	TypeDependence::Instantiation) &
6370	~TypeDependence::UnexpandedPack),
6371	Pattern(Pattern) {
6372	PackExpansionTypeBits.NumExpansions =
6373	NumExpansions ? *NumExpansions + 1 : 0;
6374	}
6375
6376	public:
6377	/// Retrieve the pattern of this pack expansion, which is the
6378	/// type that will be repeatedly instantiated when instantiating the
6379	/// pack expansion itself.
6380	QualType getPattern() const { return Pattern; }
6381
6382	/// Retrieve the number of expansions that this pack expansion will
6383	/// generate, if known.
6384	std::optional<unsigned> getNumExpansions() const {
6385	if (PackExpansionTypeBits.NumExpansions)
6386	return PackExpansionTypeBits.NumExpansions - 1;
6387	return std::nullopt;
6388	}
6389
6390	bool isSugared() const { return false; }
6391	QualType desugar() const { return QualType(this, 0); }
6392
6393	void Profile(llvm::FoldingSetNodeID &ID) {
6394	Profile(ID, Pattern: getPattern(), NumExpansions: getNumExpansions());
6395	}
6396
6397	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pattern,
6398	std::optional<unsigned> NumExpansions) {
6399	ID.AddPointer(Ptr: Pattern.getAsOpaquePtr());
6400	ID.AddBoolean(B: NumExpansions.has_value());
6401	if (NumExpansions)
6402	ID.AddInteger(I: *NumExpansions);
6403	}
6404
6405	static bool classof(const Type *T) {
6406	return T->getTypeClass() == PackExpansion;
6407	}
6408	};
6409
6410	/// This class wraps the list of protocol qualifiers. For types that can
6411	/// take ObjC protocol qualifers, they can subclass this class.
6412	template <class T>
6413	class ObjCProtocolQualifiers {
6414	protected:
6415	ObjCProtocolQualifiers() = default;
6416
6417	ObjCProtocolDecl * const *getProtocolStorage() const {
6418	return const_cast<ObjCProtocolQualifiers*>(this)->getProtocolStorage();
6419	}
6420
6421	ObjCProtocolDecl **getProtocolStorage() {
6422	return static_cast<T*>(this)->getProtocolStorageImpl();
6423	}
6424
6425	void setNumProtocols(unsigned N) {
6426	static_cast<T*>(this)->setNumProtocolsImpl(N);
6427	}
6428
6429	void initialize(ArrayRef<ObjCProtocolDecl *> protocols) {
6430	setNumProtocols(protocols.size());
6431	assert(getNumProtocols() == protocols.size() &&
6432	"bitfield overflow in protocol count");
6433	if (!protocols.empty())
6434	memcpy(getProtocolStorage(), protocols.data(),
6435	protocols.size() * sizeof(ObjCProtocolDecl*));
6436	}
6437
6438	public:
6439	using qual_iterator = ObjCProtocolDecl * const *;
6440	using qual_range = llvm::iterator_range<qual_iterator>;
6441
6442	qual_range quals() const { return qual_range(qual_begin(), qual_end()); }
6443	qual_iterator qual_begin() const { return getProtocolStorage(); }
6444	qual_iterator qual_end() const { return qual_begin() + getNumProtocols(); }
6445
6446	bool qual_empty() const { return getNumProtocols() == 0; }
6447
6448	/// Return the number of qualifying protocols in this type, or 0 if
6449	/// there are none.
6450	unsigned getNumProtocols() const {
6451	return static_cast<const T*>(this)->getNumProtocolsImpl();
6452	}
6453
6454	/// Fetch a protocol by index.
6455	ObjCProtocolDecl *getProtocol(unsigned I) const {
6456	assert(I < getNumProtocols() && "Out-of-range protocol access");
6457	return qual_begin()[I];
6458	}
6459
6460	/// Retrieve all of the protocol qualifiers.
6461	ArrayRef<ObjCProtocolDecl *> getProtocols() const {
6462	return ArrayRef<ObjCProtocolDecl *>(qual_begin(), getNumProtocols());
6463	}
6464	};
6465
6466	/// Represents a type parameter type in Objective C. It can take
6467	/// a list of protocols.
6468	class ObjCTypeParamType : public Type,
6469	public ObjCProtocolQualifiers<ObjCTypeParamType>,
6470	public llvm::FoldingSetNode {
6471	friend class ASTContext;
6472	friend class ObjCProtocolQualifiers<ObjCTypeParamType>;
6473
6474	/// The number of protocols stored on this type.
6475	unsigned NumProtocols : 6;
6476
6477	ObjCTypeParamDecl *OTPDecl;
6478
6479	/// The protocols are stored after the ObjCTypeParamType node. In the
6480	/// canonical type, the list of protocols are sorted alphabetically
6481	/// and uniqued.
6482	ObjCProtocolDecl **getProtocolStorageImpl();
6483
6484	/// Return the number of qualifying protocols in this interface type,
6485	/// or 0 if there are none.
6486	unsigned getNumProtocolsImpl() const {
6487	return NumProtocols;
6488	}
6489
6490	void setNumProtocolsImpl(unsigned N) {
6491	NumProtocols = N;
6492	}
6493
6494	ObjCTypeParamType(const ObjCTypeParamDecl *D,
6495	QualType can,
6496	ArrayRef<ObjCProtocolDecl *> protocols);
6497
6498	public:
6499	bool isSugared() const { return true; }
6500	QualType desugar() const { return getCanonicalTypeInternal(); }
6501
6502	static bool classof(const Type *T) {
6503	return T->getTypeClass() == ObjCTypeParam;
6504	}
6505
6506	void Profile(llvm::FoldingSetNodeID &ID);
6507	static void Profile(llvm::FoldingSetNodeID &ID,
6508	const ObjCTypeParamDecl *OTPDecl,
6509	QualType CanonicalType,
6510	ArrayRef<ObjCProtocolDecl *> protocols);
6511
6512	ObjCTypeParamDecl *getDecl() const { return OTPDecl; }
6513	};
6514
6515	/// Represents a class type in Objective C.
6516	///
6517	/// Every Objective C type is a combination of a base type, a set of
6518	/// type arguments (optional, for parameterized classes) and a list of
6519	/// protocols.
6520	///
6521	/// Given the following declarations:
6522	/// \code
6523	/// \@class C<T>;
6524	/// \@protocol P;
6525	/// \endcode
6526	///
6527	/// 'C' is an ObjCInterfaceType C. It is sugar for an ObjCObjectType
6528	/// with base C and no protocols.
6529	///
6530	/// 'C<P>' is an unspecialized ObjCObjectType with base C and protocol list [P].
6531	/// 'C<C*>' is a specialized ObjCObjectType with type arguments 'C*' and no
6532	/// protocol list.
6533	/// 'C<C*><P>' is a specialized ObjCObjectType with base C, type arguments 'C*',
6534	/// and protocol list [P].
6535	///
6536	/// 'id' is a TypedefType which is sugar for an ObjCObjectPointerType whose
6537	/// pointee is an ObjCObjectType with base BuiltinType::ObjCIdType
6538	/// and no protocols.
6539	///
6540	/// 'id<P>' is an ObjCObjectPointerType whose pointee is an ObjCObjectType
6541	/// with base BuiltinType::ObjCIdType and protocol list [P]. Eventually
6542	/// this should get its own sugar class to better represent the source.
6543	class ObjCObjectType : public Type,
6544	public ObjCProtocolQualifiers<ObjCObjectType> {
6545	friend class ObjCProtocolQualifiers<ObjCObjectType>;
6546
6547	// ObjCObjectType.NumTypeArgs - the number of type arguments stored
6548	// after the ObjCObjectPointerType node.
6549	// ObjCObjectType.NumProtocols - the number of protocols stored
6550	// after the type arguments of ObjCObjectPointerType node.
6551	//
6552	// These protocols are those written directly on the type. If
6553	// protocol qualifiers ever become additive, the iterators will need
6554	// to get kindof complicated.
6555	//
6556	// In the canonical object type, these are sorted alphabetically
6557	// and uniqued.
6558
6559	/// Either a BuiltinType or an InterfaceType or sugar for either.
6560	QualType BaseType;
6561
6562	/// Cached superclass type.
6563	mutable llvm::PointerIntPair<const ObjCObjectType *, 1, bool>
6564	CachedSuperClassType;
6565
6566	QualType *getTypeArgStorage();
6567	const QualType *getTypeArgStorage() const {
6568	return const_cast<ObjCObjectType *>(this)->getTypeArgStorage();
6569	}
6570
6571	ObjCProtocolDecl **getProtocolStorageImpl();
6572	/// Return the number of qualifying protocols in this interface type,
6573	/// or 0 if there are none.
6574	unsigned getNumProtocolsImpl() const {
6575	return ObjCObjectTypeBits.NumProtocols;
6576	}
6577	void setNumProtocolsImpl(unsigned N) {
6578	ObjCObjectTypeBits.NumProtocols = N;
6579	}
6580
6581	protected:
6582	enum Nonce_ObjCInterface { Nonce_ObjCInterface };
6583
6584	ObjCObjectType(QualType Canonical, QualType Base,
6585	ArrayRef<QualType> typeArgs,
6586	ArrayRef<ObjCProtocolDecl *> protocols,
6587	bool isKindOf);
6588
6589	ObjCObjectType(enum Nonce_ObjCInterface)
6590	: Type(ObjCInterface, QualType(), TypeDependence::None),
6591	BaseType(QualType(this_(), 0)) {
6592	ObjCObjectTypeBits.NumProtocols = 0;
6593	ObjCObjectTypeBits.NumTypeArgs = 0;
6594	ObjCObjectTypeBits.IsKindOf = 0;
6595	}
6596
6597	void computeSuperClassTypeSlow() const;
6598
6599	public:
6600	/// Gets the base type of this object type. This is always (possibly
6601	/// sugar for) one of:
6602	/// - the 'id' builtin type (as opposed to the 'id' type visible to the
6603	/// user, which is a typedef for an ObjCObjectPointerType)
6604	/// - the 'Class' builtin type (same caveat)
6605	/// - an ObjCObjectType (currently always an ObjCInterfaceType)
6606	QualType getBaseType() const { return BaseType; }
6607
6608	bool isObjCId() const {
6609	return getBaseType()->isSpecificBuiltinType(K: BuiltinType::ObjCId);
6610	}
6611
6612	bool isObjCClass() const {
6613	return getBaseType()->isSpecificBuiltinType(K: BuiltinType::ObjCClass);
6614	}
6615
6616	bool isObjCUnqualifiedId() const { return qual_empty() && isObjCId(); }
6617	bool isObjCUnqualifiedClass() const { return qual_empty() && isObjCClass(); }
6618	bool isObjCUnqualifiedIdOrClass() const {
6619	if (!qual_empty()) return false;
6620	if (const BuiltinType *T = getBaseType()->getAs<BuiltinType>())
6621	return T->getKind() == BuiltinType::ObjCId ||
6622	T->getKind() == BuiltinType::ObjCClass;
6623	return false;
6624	}
6625	bool isObjCQualifiedId() const { return !qual_empty() && isObjCId(); }
6626	bool isObjCQualifiedClass() const { return !qual_empty() && isObjCClass(); }
6627
6628	/// Gets the interface declaration for this object type, if the base type
6629	/// really is an interface.
6630	ObjCInterfaceDecl *getInterface() const;
6631
6632	/// Determine whether this object type is "specialized", meaning
6633	/// that it has type arguments.
6634	bool isSpecialized() const;
6635
6636	/// Determine whether this object type was written with type arguments.
6637	bool isSpecializedAsWritten() const {
6638	return ObjCObjectTypeBits.NumTypeArgs > 0;
6639	}
6640
6641	/// Determine whether this object type is "unspecialized", meaning
6642	/// that it has no type arguments.
6643	bool isUnspecialized() const { return !isSpecialized(); }
6644
6645	/// Determine whether this object type is "unspecialized" as
6646	/// written, meaning that it has no type arguments.
6647	bool isUnspecializedAsWritten() const { return !isSpecializedAsWritten(); }
6648
6649	/// Retrieve the type arguments of this object type (semantically).
6650	ArrayRef<QualType> getTypeArgs() const;
6651
6652	/// Retrieve the type arguments of this object type as they were
6653	/// written.
6654	ArrayRef<QualType> getTypeArgsAsWritten() const {
6655	return llvm::ArrayRef(getTypeArgStorage(), ObjCObjectTypeBits.NumTypeArgs);
6656	}
6657
6658	/// Whether this is a "__kindof" type as written.
6659	bool isKindOfTypeAsWritten() const { return ObjCObjectTypeBits.IsKindOf; }
6660
6661	/// Whether this ia a "__kindof" type (semantically).
6662	bool isKindOfType() const;
6663
6664	/// Retrieve the type of the superclass of this object type.
6665	///
6666	/// This operation substitutes any type arguments into the
6667	/// superclass of the current class type, potentially producing a
6668	/// specialization of the superclass type. Produces a null type if
6669	/// there is no superclass.
6670	QualType getSuperClassType() const {
6671	if (!CachedSuperClassType.getInt())
6672	computeSuperClassTypeSlow();
6673
6674	assert(CachedSuperClassType.getInt() && "Superclass not set?");
6675	return QualType(CachedSuperClassType.getPointer(), 0);
6676	}
6677
6678	/// Strip off the Objective-C "kindof" type and (with it) any
6679	/// protocol qualifiers.
6680	QualType stripObjCKindOfTypeAndQuals(const ASTContext &ctx) const;
6681
6682	bool isSugared() const { return false; }
6683	QualType desugar() const { return QualType(this, 0); }
6684
6685	static bool classof(const Type *T) {
6686	return T->getTypeClass() == ObjCObject ||
6687	T->getTypeClass() == ObjCInterface;
6688	}
6689	};
6690
6691	/// A class providing a concrete implementation
6692	/// of ObjCObjectType, so as to not increase the footprint of
6693	/// ObjCInterfaceType. Code outside of ASTContext and the core type
6694	/// system should not reference this type.
6695	class ObjCObjectTypeImpl : public ObjCObjectType, public llvm::FoldingSetNode {
6696	friend class ASTContext;
6697
6698	// If anyone adds fields here, ObjCObjectType::getProtocolStorage()
6699	// will need to be modified.
6700
6701	ObjCObjectTypeImpl(QualType Canonical, QualType Base,
6702	ArrayRef<QualType> typeArgs,
6703	ArrayRef<ObjCProtocolDecl *> protocols,
6704	bool isKindOf)
6705	: ObjCObjectType(Canonical, Base, typeArgs, protocols, isKindOf) {}
6706
6707	public:
6708	void Profile(llvm::FoldingSetNodeID &ID);
6709	static void Profile(llvm::FoldingSetNodeID &ID,
6710	QualType Base,
6711	ArrayRef<QualType> typeArgs,
6712	ArrayRef<ObjCProtocolDecl *> protocols,
6713	bool isKindOf);
6714	};
6715
6716	inline QualType *ObjCObjectType::getTypeArgStorage() {
6717	return reinterpret_cast<QualType *>(static_cast<ObjCObjectTypeImpl*>(this)+1);
6718	}
6719
6720	inline ObjCProtocolDecl **ObjCObjectType::getProtocolStorageImpl() {
6721	return reinterpret_cast<ObjCProtocolDecl**>(
6722	getTypeArgStorage() + ObjCObjectTypeBits.NumTypeArgs);
6723	}
6724
6725	inline ObjCProtocolDecl **ObjCTypeParamType::getProtocolStorageImpl() {
6726	return reinterpret_cast<ObjCProtocolDecl**>(
6727	static_cast<ObjCTypeParamType*>(this)+1);
6728	}
6729
6730	/// Interfaces are the core concept in Objective-C for object oriented design.
6731	/// They basically correspond to C++ classes. There are two kinds of interface
6732	/// types: normal interfaces like `NSString`, and qualified interfaces, which
6733	/// are qualified with a protocol list like `NSString<NSCopyable, NSAmazing>`.
6734	///
6735	/// ObjCInterfaceType guarantees the following properties when considered
6736	/// as a subtype of its superclass, ObjCObjectType:
6737	/// - There are no protocol qualifiers. To reinforce this, code which
6738	/// tries to invoke the protocol methods via an ObjCInterfaceType will
6739	/// fail to compile.
6740	/// - It is its own base type. That is, if T is an ObjCInterfaceType*,
6741	/// T->getBaseType() == QualType(T, 0).
6742	class ObjCInterfaceType : public ObjCObjectType {
6743	friend class ASTContext; // ASTContext creates these.
6744	friend class ASTReader;
6745	template <class T> friend class serialization::AbstractTypeReader;
6746
6747	ObjCInterfaceDecl *Decl;
6748
6749	ObjCInterfaceType(const ObjCInterfaceDecl *D)
6750	: ObjCObjectType(Nonce_ObjCInterface),
6751	Decl(const_cast<ObjCInterfaceDecl*>(D)) {}
6752
6753	public:
6754	/// Get the declaration of this interface.
6755	ObjCInterfaceDecl *getDecl() const;
6756
6757	bool isSugared() const { return false; }
6758	QualType desugar() const { return QualType(this, 0); }
6759
6760	static bool classof(const Type *T) {
6761	return T->getTypeClass() == ObjCInterface;
6762	}
6763
6764	// Nonsense to "hide" certain members of ObjCObjectType within this
6765	// class. People asking for protocols on an ObjCInterfaceType are
6766	// not going to get what they want: ObjCInterfaceTypes are
6767	// guaranteed to have no protocols.
6768	enum {
6769	qual_iterator,
6770	qual_begin,
6771	qual_end,
6772	getNumProtocols,
6773	getProtocol
6774	};
6775	};
6776
6777	inline ObjCInterfaceDecl *ObjCObjectType::getInterface() const {
6778	QualType baseType = getBaseType();
6779	while (const auto *ObjT = baseType->getAs<ObjCObjectType>()) {
6780	if (const auto *T = dyn_cast<ObjCInterfaceType>(ObjT))
6781	return T->getDecl();
6782
6783	baseType = ObjT->getBaseType();
6784	}
6785
6786	return nullptr;
6787	}
6788
6789	/// Represents a pointer to an Objective C object.
6790	///
6791	/// These are constructed from pointer declarators when the pointee type is
6792	/// an ObjCObjectType (or sugar for one). In addition, the 'id' and 'Class'
6793	/// types are typedefs for these, and the protocol-qualified types 'id<P>'
6794	/// and 'Class<P>' are translated into these.
6795	///
6796	/// Pointers to pointers to Objective C objects are still PointerTypes;
6797	/// only the first level of pointer gets it own type implementation.
6798	class ObjCObjectPointerType : public Type, public llvm::FoldingSetNode {
6799	friend class ASTContext; // ASTContext creates these.
6800
6801	QualType PointeeType;
6802
6803	ObjCObjectPointerType(QualType Canonical, QualType Pointee)
6804	: Type(ObjCObjectPointer, Canonical, Pointee->getDependence()),
6805	PointeeType(Pointee) {}
6806
6807	public:
6808	/// Gets the type pointed to by this ObjC pointer.
6809	/// The result will always be an ObjCObjectType or sugar thereof.
6810	QualType getPointeeType() const { return PointeeType; }
6811
6812	/// Gets the type pointed to by this ObjC pointer. Always returns non-null.
6813	///
6814	/// This method is equivalent to getPointeeType() except that
6815	/// it discards any typedefs (or other sugar) between this
6816	/// type and the "outermost" object type. So for:
6817	/// \code
6818	/// \@class A; \@protocol P; \@protocol Q;
6819	/// typedef A<P> AP;
6820	/// typedef A A1;
6821	/// typedef A1<P> A1P;
6822	/// typedef A1P<Q> A1PQ;
6823	/// \endcode
6824	/// For 'A*', getObjectType() will return 'A'.
6825	/// For 'A<P>*', getObjectType() will return 'A<P>'.
6826	/// For 'AP*', getObjectType() will return 'A<P>'.
6827	/// For 'A1*', getObjectType() will return 'A'.
6828	/// For 'A1<P>*', getObjectType() will return 'A1<P>'.
6829	/// For 'A1P*', getObjectType() will return 'A1<P>'.
6830	/// For 'A1PQ*', getObjectType() will return 'A1<Q>', because
6831	/// adding protocols to a protocol-qualified base discards the
6832	/// old qualifiers (for now). But if it didn't, getObjectType()
6833	/// would return 'A1P<Q>' (and we'd have to make iterating over
6834	/// qualifiers more complicated).
6835	const ObjCObjectType *getObjectType() const {
6836	return PointeeType->castAs<ObjCObjectType>();
6837	}
6838
6839	/// If this pointer points to an Objective C
6840	/// \@interface type, gets the type for that interface. Any protocol
6841	/// qualifiers on the interface are ignored.
6842	///
6843	/// \return null if the base type for this pointer is 'id' or 'Class'
6844	const ObjCInterfaceType *getInterfaceType() const;
6845
6846	/// If this pointer points to an Objective \@interface
6847	/// type, gets the declaration for that interface.
6848	///
6849	/// \return null if the base type for this pointer is 'id' or 'Class'
6850	ObjCInterfaceDecl *getInterfaceDecl() const {
6851	return getObjectType()->getInterface();
6852	}
6853
6854	/// True if this is equivalent to the 'id' type, i.e. if
6855	/// its object type is the primitive 'id' type with no protocols.
6856	bool isObjCIdType() const {
6857	return getObjectType()->isObjCUnqualifiedId();
6858	}
6859
6860	/// True if this is equivalent to the 'Class' type,
6861	/// i.e. if its object tive is the primitive 'Class' type with no protocols.
6862	bool isObjCClassType() const {
6863	return getObjectType()->isObjCUnqualifiedClass();
6864	}
6865
6866	/// True if this is equivalent to the 'id' or 'Class' type,
6867	bool isObjCIdOrClassType() const {
6868	return getObjectType()->isObjCUnqualifiedIdOrClass();
6869	}
6870
6871	/// True if this is equivalent to 'id<P>' for some non-empty set of
6872	/// protocols.
6873	bool isObjCQualifiedIdType() const {
6874	return getObjectType()->isObjCQualifiedId();
6875	}
6876
6877	/// True if this is equivalent to 'Class<P>' for some non-empty set of
6878	/// protocols.
6879	bool isObjCQualifiedClassType() const {
6880	return getObjectType()->isObjCQualifiedClass();
6881	}
6882
6883	/// Whether this is a "__kindof" type.
6884	bool isKindOfType() const { return getObjectType()->isKindOfType(); }
6885
6886	/// Whether this type is specialized, meaning that it has type arguments.
6887	bool isSpecialized() const { return getObjectType()->isSpecialized(); }
6888
6889	/// Whether this type is specialized, meaning that it has type arguments.
6890	bool isSpecializedAsWritten() const {
6891	return getObjectType()->isSpecializedAsWritten();
6892	}
6893
6894	/// Whether this type is unspecialized, meaning that is has no type arguments.
6895	bool isUnspecialized() const { return getObjectType()->isUnspecialized(); }
6896
6897	/// Determine whether this object type is "unspecialized" as
6898	/// written, meaning that it has no type arguments.
6899	bool isUnspecializedAsWritten() const { return !isSpecializedAsWritten(); }
6900
6901	/// Retrieve the type arguments for this type.
6902	ArrayRef<QualType> getTypeArgs() const {
6903	return getObjectType()->getTypeArgs();
6904	}
6905
6906	/// Retrieve the type arguments for this type.
6907	ArrayRef<QualType> getTypeArgsAsWritten() const {
6908	return getObjectType()->getTypeArgsAsWritten();
6909	}
6910
6911	/// An iterator over the qualifiers on the object type. Provided
6912	/// for convenience. This will always iterate over the full set of
6913	/// protocols on a type, not just those provided directly.
6914	using qual_iterator = ObjCObjectType::qual_iterator;
6915	using qual_range = llvm::iterator_range<qual_iterator>;
6916
6917	qual_range quals() const { return qual_range(qual_begin(), qual_end()); }
6918
6919	qual_iterator qual_begin() const {
6920	return getObjectType()->qual_begin();
6921	}
6922
6923	qual_iterator qual_end() const {
6924	return getObjectType()->qual_end();
6925	}
6926
6927	bool qual_empty() const { return getObjectType()->qual_empty(); }
6928
6929	/// Return the number of qualifying protocols on the object type.
6930	unsigned getNumProtocols() const {
6931	return getObjectType()->getNumProtocols();
6932	}
6933
6934	/// Retrieve a qualifying protocol by index on the object type.
6935	ObjCProtocolDecl *getProtocol(unsigned I) const {
6936	return getObjectType()->getProtocol(I);
6937	}
6938
6939	bool isSugared() const { return false; }
6940	QualType desugar() const { return QualType(this, 0); }
6941
6942	/// Retrieve the type of the superclass of this object pointer type.
6943	///
6944	/// This operation substitutes any type arguments into the
6945	/// superclass of the current class type, potentially producing a
6946	/// pointer to a specialization of the superclass type. Produces a
6947	/// null type if there is no superclass.
6948	QualType getSuperClassType() const;
6949
6950	/// Strip off the Objective-C "kindof" type and (with it) any
6951	/// protocol qualifiers.
6952	const ObjCObjectPointerType *stripObjCKindOfTypeAndQuals(
6953	const ASTContext &ctx) const;
6954
6955	void Profile(llvm::FoldingSetNodeID &ID) {
6956	Profile(ID, T: getPointeeType());
6957	}
6958
6959	static void Profile(llvm::FoldingSetNodeID &ID, QualType T) {
6960	ID.AddPointer(Ptr: T.getAsOpaquePtr());
6961	}
6962
6963	static bool classof(const Type *T) {
6964	return T->getTypeClass() == ObjCObjectPointer;
6965	}
6966	};
6967
6968	class AtomicType : public Type, public llvm::FoldingSetNode {
6969	friend class ASTContext; // ASTContext creates these.
6970
6971	QualType ValueType;
6972
6973	AtomicType(QualType ValTy, QualType Canonical)
6974	: Type(Atomic, Canonical, ValTy->getDependence()), ValueType(ValTy) {}
6975
6976	public:
6977	/// Gets the type contained by this atomic type, i.e.
6978	/// the type returned by performing an atomic load of this atomic type.
6979	QualType getValueType() const { return ValueType; }
6980
6981	bool isSugared() const { return false; }
6982	QualType desugar() const { return QualType(this, 0); }
6983
6984	void Profile(llvm::FoldingSetNodeID &ID) {
6985	Profile(ID, T: getValueType());
6986	}
6987
6988	static void Profile(llvm::FoldingSetNodeID &ID, QualType T) {
6989	ID.AddPointer(Ptr: T.getAsOpaquePtr());
6990	}
6991
6992	static bool classof(const Type *T) {
6993	return T->getTypeClass() == Atomic;
6994	}
6995	};
6996
6997	/// PipeType - OpenCL20.
6998	class PipeType : public Type, public llvm::FoldingSetNode {
6999	friend class ASTContext; // ASTContext creates these.
7000
7001	QualType ElementType;
7002	bool isRead;
7003
7004	PipeType(QualType elemType, QualType CanonicalPtr, bool isRead)
7005	: Type(Pipe, CanonicalPtr, elemType->getDependence()),
7006	ElementType(elemType), isRead(isRead) {}
7007
7008	public:
7009	QualType getElementType() const { return ElementType; }
7010
7011	bool isSugared() const { return false; }
7012
7013	QualType desugar() const { return QualType(this, 0); }
7014
7015	void Profile(llvm::FoldingSetNodeID &ID) {
7016	Profile(ID, T: getElementType(), isRead: isReadOnly());
7017	}
7018
7019	static void Profile(llvm::FoldingSetNodeID &ID, QualType T, bool isRead) {
7020	ID.AddPointer(Ptr: T.getAsOpaquePtr());
7021	ID.AddBoolean(B: isRead);
7022	}
7023
7024	static bool classof(const Type *T) {
7025	return T->getTypeClass() == Pipe;
7026	}
7027
7028	bool isReadOnly() const { return isRead; }
7029	};
7030
7031	/// A fixed int type of a specified bitwidth.
7032	class BitIntType final : public Type, public llvm::FoldingSetNode {
7033	friend class ASTContext;
7034	LLVM_PREFERRED_TYPE(bool)
7035	unsigned IsUnsigned : 1;
7036	unsigned NumBits : 24;
7037
7038	protected:
7039	BitIntType(bool isUnsigned, unsigned NumBits);
7040
7041	public:
7042	bool isUnsigned() const { return IsUnsigned; }
7043	bool isSigned() const { return !IsUnsigned; }
7044	unsigned getNumBits() const { return NumBits; }
7045
7046	bool isSugared() const { return false; }
7047	QualType desugar() const { return QualType(this, 0); }
7048
7049	void Profile(llvm::FoldingSetNodeID &ID) const {
7050	Profile(ID, IsUnsigned: isUnsigned(), NumBits: getNumBits());
7051	}
7052
7053	static void Profile(llvm::FoldingSetNodeID &ID, bool IsUnsigned,
7054	unsigned NumBits) {
7055	ID.AddBoolean(B: IsUnsigned);
7056	ID.AddInteger(I: NumBits);
7057	}
7058
7059	static bool classof(const Type *T) { return T->getTypeClass() == BitInt; }
7060	};
7061
7062	class DependentBitIntType final : public Type, public llvm::FoldingSetNode {
7063	friend class ASTContext;
7064	llvm::PointerIntPair<Expr*, 1, bool> ExprAndUnsigned;
7065
7066	protected:
7067	DependentBitIntType(bool IsUnsigned, Expr *NumBits);
7068
7069	public:
7070	bool isUnsigned() const;
7071	bool isSigned() const { return !isUnsigned(); }
7072	Expr *getNumBitsExpr() const;
7073
7074	bool isSugared() const { return false; }
7075	QualType desugar() const { return QualType(this, 0); }
7076
7077	void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
7078	Profile(ID, Context, IsUnsigned: isUnsigned(), NumBitsExpr: getNumBitsExpr());
7079	}
7080	static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
7081	bool IsUnsigned, Expr *NumBitsExpr);
7082
7083	static bool classof(const Type *T) {
7084	return T->getTypeClass() == DependentBitInt;
7085	}
7086	};
7087
7088	/// A qualifier set is used to build a set of qualifiers.
7089	class QualifierCollector : public Qualifiers {
7090	public:
7091	QualifierCollector(Qualifiers Qs = Qualifiers()) : Qualifiers(Qs) {}
7092
7093	/// Collect any qualifiers on the given type and return an
7094	/// unqualified type. The qualifiers are assumed to be consistent
7095	/// with those already in the type.
7096	const Type *strip(QualType type) {
7097	addFastQualifiers(mask: type.getLocalFastQualifiers());
7098	if (!type.hasLocalNonFastQualifiers())
7099	return type.getTypePtrUnsafe();
7100
7101	const ExtQuals *extQuals = type.getExtQualsUnsafe();
7102	addConsistentQualifiers(qs: extQuals->getQualifiers());
7103	return extQuals->getBaseType();
7104	}
7105
7106	/// Apply the collected qualifiers to the given type.
7107	QualType apply(const ASTContext &Context, QualType QT) const;
7108
7109	/// Apply the collected qualifiers to the given type.
7110	QualType apply(const ASTContext &Context, const Type* T) const;
7111	};
7112
7113	/// A container of type source information.
7114	///
7115	/// A client can read the relevant info using TypeLoc wrappers, e.g:
7116	/// @code
7117	/// TypeLoc TL = TypeSourceInfo->getTypeLoc();
7118	/// TL.getBeginLoc().print(OS, SrcMgr);
7119	/// @endcode
7120	class alignas(8) TypeSourceInfo {
7121	// Contains a memory block after the class, used for type source information,
7122	// allocated by ASTContext.
7123	friend class ASTContext;
7124
7125	QualType Ty;
7126
7127	TypeSourceInfo(QualType ty, size_t DataSize); // implemented in TypeLoc.h
7128
7129	public:
7130	/// Return the type wrapped by this type source info.
7131	QualType getType() const { return Ty; }
7132
7133	/// Return the TypeLoc wrapper for the type source info.
7134	TypeLoc getTypeLoc() const; // implemented in TypeLoc.h
7135
7136	/// Override the type stored in this TypeSourceInfo. Use with caution!
7137	void overrideType(QualType T) { Ty = T; }
7138	};
7139
7140	// Inline function definitions.
7141
7142	inline SplitQualType SplitQualType::getSingleStepDesugaredType() const {
7143	SplitQualType desugar =
7144	Ty->getLocallyUnqualifiedSingleStepDesugaredType().split();
7145	desugar.Quals.addConsistentQualifiers(qs: Quals);
7146	return desugar;
7147	}
7148
7149	inline const Type *QualType::getTypePtr() const {
7150	return getCommonPtr()->BaseType;
7151	}
7152
7153	inline const Type *QualType::getTypePtrOrNull() const {
7154	return (isNull() ? nullptr : getCommonPtr()->BaseType);
7155	}
7156
7157	inline bool QualType::isReferenceable() const {
7158	// C++ [defns.referenceable]
7159	// type that is either an object type, a function type that does not have
7160	// cv-qualifiers or a ref-qualifier, or a reference type.
7161	const Type &Self = **this;
7162	if (Self.isObjectType() || Self.isReferenceType())
7163	return true;
7164	if (const auto *F = Self.getAs<FunctionProtoType>())
7165	return F->getMethodQuals().empty() && F->getRefQualifier() == RQ_None;
7166
7167	return false;
7168	}
7169
7170	inline SplitQualType QualType::split() const {
7171	if (!hasLocalNonFastQualifiers())
7172	return SplitQualType(getTypePtrUnsafe(),
7173	Qualifiers::fromFastMask(Mask: getLocalFastQualifiers()));
7174
7175	const ExtQuals *eq = getExtQualsUnsafe();
7176	Qualifiers qs = eq->getQualifiers();
7177	qs.addFastQualifiers(mask: getLocalFastQualifiers());
7178	return SplitQualType(eq->getBaseType(), qs);
7179	}
7180
7181	inline Qualifiers QualType::getLocalQualifiers() const {
7182	Qualifiers Quals;
7183	if (hasLocalNonFastQualifiers())
7184	Quals = getExtQualsUnsafe()->getQualifiers();
7185	Quals.addFastQualifiers(mask: getLocalFastQualifiers());
7186	return Quals;
7187	}
7188
7189	inline Qualifiers QualType::getQualifiers() const {
7190	Qualifiers quals = getCommonPtr()->CanonicalType.getLocalQualifiers();
7191	quals.addFastQualifiers(mask: getLocalFastQualifiers());
7192	return quals;
7193	}
7194
7195	inline unsigned QualType::getCVRQualifiers() const {
7196	unsigned cvr = getCommonPtr()->CanonicalType.getLocalCVRQualifiers();
7197	cvr |= getLocalCVRQualifiers();
7198	return cvr;
7199	}
7200
7201	inline QualType QualType::getCanonicalType() const {
7202	QualType canon = getCommonPtr()->CanonicalType;
7203	return canon.withFastQualifiers(TQs: getLocalFastQualifiers());
7204	}
7205
7206	inline bool QualType::isCanonical() const {
7207	return getTypePtr()->isCanonicalUnqualified();
7208	}
7209
7210	inline bool QualType::isCanonicalAsParam() const {
7211	if (!isCanonical()) return false;
7212	if (hasLocalQualifiers()) return false;
7213
7214	const Type *T = getTypePtr();
7215	if (T->isVariablyModifiedType() && T->hasSizedVLAType())
7216	return false;
7217
7218	return !isa<FunctionType>(T) &&
7219	(!isa<ArrayType>(T) || isa<ArrayParameterType>(T));
7220	}
7221
7222	inline bool QualType::isConstQualified() const {
7223	return isLocalConstQualified() ||
7224	getCommonPtr()->CanonicalType.isLocalConstQualified();
7225	}
7226
7227	inline bool QualType::isRestrictQualified() const {
7228	return isLocalRestrictQualified() ||
7229	getCommonPtr()->CanonicalType.isLocalRestrictQualified();
7230	}
7231
7232
7233	inline bool QualType::isVolatileQualified() const {
7234	return isLocalVolatileQualified() ||
7235	getCommonPtr()->CanonicalType.isLocalVolatileQualified();
7236	}
7237
7238	inline bool QualType::hasQualifiers() const {
7239	return hasLocalQualifiers() ||
7240	getCommonPtr()->CanonicalType.hasLocalQualifiers();
7241	}
7242
7243	inline QualType QualType::getUnqualifiedType() const {
7244	if (!getTypePtr()->getCanonicalTypeInternal().hasLocalQualifiers())
7245	return QualType(getTypePtr(), 0);
7246
7247	return QualType(getSplitUnqualifiedTypeImpl(type: *this).Ty, 0);
7248	}
7249
7250	inline SplitQualType QualType::getSplitUnqualifiedType() const {
7251	if (!getTypePtr()->getCanonicalTypeInternal().hasLocalQualifiers())
7252	return split();
7253
7254	return getSplitUnqualifiedTypeImpl(type: *this);
7255	}
7256
7257	inline void QualType::removeLocalConst() {
7258	removeLocalFastQualifiers(Mask: Qualifiers::Const);
7259	}
7260
7261	inline void QualType::removeLocalRestrict() {
7262	removeLocalFastQualifiers(Mask: Qualifiers::Restrict);
7263	}
7264
7265	inline void QualType::removeLocalVolatile() {
7266	removeLocalFastQualifiers(Mask: Qualifiers::Volatile);
7267	}
7268
7269	/// Check if this type has any address space qualifier.
7270	inline bool QualType::hasAddressSpace() const {
7271	return getQualifiers().hasAddressSpace();
7272	}
7273
7274	/// Return the address space of this type.
7275	inline LangAS QualType::getAddressSpace() const {
7276	return getQualifiers().getAddressSpace();
7277	}
7278
7279	/// Return the gc attribute of this type.
7280	inline Qualifiers::GC QualType::getObjCGCAttr() const {
7281	return getQualifiers().getObjCGCAttr();
7282	}
7283
7284	inline bool QualType::hasNonTrivialToPrimitiveDefaultInitializeCUnion() const {
7285	if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
7286	return hasNonTrivialToPrimitiveDefaultInitializeCUnion(RD);
7287	return false;
7288	}
7289
7290	inline bool QualType::hasNonTrivialToPrimitiveDestructCUnion() const {
7291	if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
7292	return hasNonTrivialToPrimitiveDestructCUnion(RD);
7293	return false;
7294	}
7295
7296	inline bool QualType::hasNonTrivialToPrimitiveCopyCUnion() const {
7297	if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
7298	return hasNonTrivialToPrimitiveCopyCUnion(RD);
7299	return false;
7300	}
7301
7302	inline FunctionType::ExtInfo getFunctionExtInfo(const Type &t) {
7303	if (const auto *PT = t.getAs<PointerType>()) {
7304	if (const auto *FT = PT->getPointeeType()->getAs<FunctionType>())
7305	return FT->getExtInfo();
7306	} else if (const auto *FT = t.getAs<FunctionType>())
7307	return FT->getExtInfo();
7308
7309	return FunctionType::ExtInfo();
7310	}
7311
7312	inline FunctionType::ExtInfo getFunctionExtInfo(QualType t) {
7313	return getFunctionExtInfo(t: *t);
7314	}
7315
7316	/// Determine whether this type is more
7317	/// qualified than the Other type. For example, "const volatile int"
7318	/// is more qualified than "const int", "volatile int", and
7319	/// "int". However, it is not more qualified than "const volatile
7320	/// int".
7321	inline bool QualType::isMoreQualifiedThan(QualType other) const {
7322	Qualifiers MyQuals = getQualifiers();
7323	Qualifiers OtherQuals = other.getQualifiers();
7324	return (MyQuals != OtherQuals && MyQuals.compatiblyIncludes(other: OtherQuals));
7325	}
7326
7327	/// Determine whether this type is at last
7328	/// as qualified as the Other type. For example, "const volatile
7329	/// int" is at least as qualified as "const int", "volatile int",
7330	/// "int", and "const volatile int".
7331	inline bool QualType::isAtLeastAsQualifiedAs(QualType other) const {
7332	Qualifiers OtherQuals = other.getQualifiers();
7333
7334	// Ignore __unaligned qualifier if this type is a void.
7335	if (getUnqualifiedType()->isVoidType())
7336	OtherQuals.removeUnaligned();
7337
7338	return getQualifiers().compatiblyIncludes(other: OtherQuals);
7339	}
7340
7341	/// If Type is a reference type (e.g., const
7342	/// int&), returns the type that the reference refers to ("const
7343	/// int"). Otherwise, returns the type itself. This routine is used
7344	/// throughout Sema to implement C++ 5p6:
7345	///
7346	/// If an expression initially has the type "reference to T" (8.3.2,
7347	/// 8.5.3), the type is adjusted to "T" prior to any further
7348	/// analysis, the expression designates the object or function
7349	/// denoted by the reference, and the expression is an lvalue.
7350	inline QualType QualType::getNonReferenceType() const {
7351	if (const auto *RefType = (*this)->getAs<ReferenceType>())
7352	return RefType->getPointeeType();
7353	else
7354	return *this;
7355	}
7356
7357	inline bool QualType::isCForbiddenLValueType() const {
7358	return ((getTypePtr()->isVoidType() && !hasQualifiers()) ||
7359	getTypePtr()->isFunctionType());
7360	}
7361
7362	/// Tests whether the type is categorized as a fundamental type.
7363	///
7364	/// \returns True for types specified in C++0x [basic.fundamental].
7365	inline bool Type::isFundamentalType() const {
7366	return isVoidType() ||
7367	isNullPtrType() ||
7368	// FIXME: It's really annoying that we don't have an
7369	// 'isArithmeticType()' which agrees with the standard definition.
7370	(isArithmeticType() && !isEnumeralType());
7371	}
7372
7373	/// Tests whether the type is categorized as a compound type.
7374	///
7375	/// \returns True for types specified in C++0x [basic.compound].
7376	inline bool Type::isCompoundType() const {
7377	// C++0x [basic.compound]p1:
7378	// Compound types can be constructed in the following ways:
7379	// -- arrays of objects of a given type [...];
7380	return isArrayType() ||
7381	// -- functions, which have parameters of given types [...];
7382	isFunctionType() ||
7383	// -- pointers to void or objects or functions [...];
7384	isPointerType() ||
7385	// -- references to objects or functions of a given type. [...]
7386	isReferenceType() ||
7387	// -- classes containing a sequence of objects of various types, [...];
7388	isRecordType() ||
7389	// -- unions, which are classes capable of containing objects of different
7390	// types at different times;
7391	isUnionType() ||
7392	// -- enumerations, which comprise a set of named constant values. [...];
7393	isEnumeralType() ||
7394	// -- pointers to non-static class members, [...].
7395	isMemberPointerType();
7396	}
7397
7398	inline bool Type::isFunctionType() const {
7399	return isa<FunctionType>(CanonicalType);
7400	}
7401
7402	inline bool Type::isPointerType() const {
7403	return isa<PointerType>(CanonicalType);
7404	}
7405
7406	inline bool Type::isAnyPointerType() const {
7407	return isPointerType() || isObjCObjectPointerType();
7408	}
7409
7410	inline bool Type::isBlockPointerType() const {
7411	return isa<BlockPointerType>(CanonicalType);
7412	}
7413
7414	inline bool Type::isReferenceType() const {
7415	return isa<ReferenceType>(CanonicalType);
7416	}
7417
7418	inline bool Type::isLValueReferenceType() const {
7419	return isa<LValueReferenceType>(CanonicalType);
7420	}
7421
7422	inline bool Type::isRValueReferenceType() const {
7423	return isa<RValueReferenceType>(CanonicalType);
7424	}
7425
7426	inline bool Type::isObjectPointerType() const {
7427	// Note: an "object pointer type" is not the same thing as a pointer to an
7428	// object type; rather, it is a pointer to an object type or a pointer to cv
7429	// void.
7430	if (const auto *T = getAs<PointerType>())
7431	return !T->getPointeeType()->isFunctionType();
7432	else
7433	return false;
7434	}
7435
7436	inline bool Type::isFunctionPointerType() const {
7437	if (const auto *T = getAs<PointerType>())
7438	return T->getPointeeType()->isFunctionType();
7439	else
7440	return false;
7441	}
7442
7443	inline bool Type::isFunctionReferenceType() const {
7444	if (const auto *T = getAs<ReferenceType>())
7445	return T->getPointeeType()->isFunctionType();
7446	else
7447	return false;
7448	}
7449
7450	inline bool Type::isMemberPointerType() const {
7451	return isa<MemberPointerType>(CanonicalType);
7452	}
7453
7454	inline bool Type::isMemberFunctionPointerType() const {
7455	if (const auto *T = getAs<MemberPointerType>())
7456	return T->isMemberFunctionPointer();
7457	else
7458	return false;
7459	}
7460
7461	inline bool Type::isMemberDataPointerType() const {
7462	if (const auto *T = getAs<MemberPointerType>())
7463	return T->isMemberDataPointer();
7464	else
7465	return false;
7466	}
7467
7468	inline bool Type::isArrayType() const {
7469	return isa<ArrayType>(CanonicalType);
7470	}
7471
7472	inline bool Type::isConstantArrayType() const {
7473	return isa<ConstantArrayType>(CanonicalType);
7474	}
7475
7476	inline bool Type::isIncompleteArrayType() const {
7477	return isa<IncompleteArrayType>(CanonicalType);
7478	}
7479
7480	inline bool Type::isVariableArrayType() const {
7481	return isa<VariableArrayType>(CanonicalType);
7482	}
7483
7484	inline bool Type::isArrayParameterType() const {
7485	return isa<ArrayParameterType>(CanonicalType);
7486	}
7487
7488	inline bool Type::isDependentSizedArrayType() const {
7489	return isa<DependentSizedArrayType>(CanonicalType);
7490	}
7491
7492	inline bool Type::isBuiltinType() const {
7493	return isa<BuiltinType>(CanonicalType);
7494	}
7495
7496	inline bool Type::isRecordType() const {
7497	return isa<RecordType>(CanonicalType);
7498	}
7499
7500	inline bool Type::isEnumeralType() const {
7501	return isa<EnumType>(CanonicalType);
7502	}
7503
7504	inline bool Type::isAnyComplexType() const {
7505	return isa<ComplexType>(CanonicalType);
7506	}
7507
7508	inline bool Type::isVectorType() const {
7509	return isa<VectorType>(CanonicalType);
7510	}
7511
7512	inline bool Type::isExtVectorType() const {
7513	return isa<ExtVectorType>(CanonicalType);
7514	}
7515
7516	inline bool Type::isExtVectorBoolType() const {
7517	if (!isExtVectorType())
7518	return false;
7519	return cast<ExtVectorType>(CanonicalType)->getElementType()->isBooleanType();
7520	}
7521
7522	inline bool Type::isMatrixType() const {
7523	return isa<MatrixType>(CanonicalType);
7524	}
7525
7526	inline bool Type::isConstantMatrixType() const {
7527	return isa<ConstantMatrixType>(CanonicalType);
7528	}
7529
7530	inline bool Type::isDependentAddressSpaceType() const {
7531	return isa<DependentAddressSpaceType>(CanonicalType);
7532	}
7533
7534	inline bool Type::isObjCObjectPointerType() const {
7535	return isa<ObjCObjectPointerType>(CanonicalType);
7536	}
7537
7538	inline bool Type::isObjCObjectType() const {
7539	return isa<ObjCObjectType>(CanonicalType);
7540	}
7541
7542	inline bool Type::isObjCObjectOrInterfaceType() const {
7543	return isa<ObjCInterfaceType>(CanonicalType) ||
7544	isa<ObjCObjectType>(CanonicalType);
7545	}
7546
7547	inline bool Type::isAtomicType() const {
7548	return isa<AtomicType>(CanonicalType);
7549	}
7550
7551	inline bool Type::isUndeducedAutoType() const {
7552	return isa<AutoType>(CanonicalType);
7553	}
7554
7555	inline bool Type::isObjCQualifiedIdType() const {
7556	if (const auto *OPT = getAs<ObjCObjectPointerType>())
7557	return OPT->isObjCQualifiedIdType();
7558	return false;
7559	}
7560
7561	inline bool Type::isObjCQualifiedClassType() const {
7562	if (const auto *OPT = getAs<ObjCObjectPointerType>())
7563	return OPT->isObjCQualifiedClassType();
7564	return false;
7565	}
7566
7567	inline bool Type::isObjCIdType() const {
7568	if (const auto *OPT = getAs<ObjCObjectPointerType>())
7569	return OPT->isObjCIdType();
7570	return false;
7571	}
7572
7573	inline bool Type::isObjCClassType() const {
7574	if (const auto *OPT = getAs<ObjCObjectPointerType>())
7575	return OPT->isObjCClassType();
7576	return false;
7577	}
7578
7579	inline bool Type::isObjCSelType() const {
7580	if (const auto *OPT = getAs<PointerType>())
7581	return OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCSel);
7582	return false;
7583	}
7584
7585	inline bool Type::isObjCBuiltinType() const {
7586	return isObjCIdType() || isObjCClassType() || isObjCSelType();
7587	}
7588
7589	inline bool Type::isDecltypeType() const {
7590	return isa<DecltypeType>(this);
7591	}
7592
7593	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
7594	inline bool Type::is##Id##Type() const { \
7595	return isSpecificBuiltinType(BuiltinType::Id); \
7596	}
7597	#include "clang/Basic/OpenCLImageTypes.def"
7598
7599	inline bool Type::isSamplerT() const {
7600	return isSpecificBuiltinType(K: BuiltinType::OCLSampler);
7601	}
7602
7603	inline bool Type::isEventT() const {
7604	return isSpecificBuiltinType(K: BuiltinType::OCLEvent);
7605	}
7606
7607	inline bool Type::isClkEventT() const {
7608	return isSpecificBuiltinType(K: BuiltinType::OCLClkEvent);
7609	}
7610
7611	inline bool Type::isQueueT() const {
7612	return isSpecificBuiltinType(K: BuiltinType::OCLQueue);
7613	}
7614
7615	inline bool Type::isReserveIDT() const {
7616	return isSpecificBuiltinType(K: BuiltinType::OCLReserveID);
7617	}
7618
7619	inline bool Type::isImageType() const {
7620	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) is##Id##Type() ||
7621	return
7622	#include "clang/Basic/OpenCLImageTypes.def"
7623	false; // end boolean or operation
7624	}
7625
7626	inline bool Type::isPipeType() const {
7627	return isa<PipeType>(CanonicalType);
7628	}
7629
7630	inline bool Type::isBitIntType() const {
7631	return isa<BitIntType>(CanonicalType);
7632	}
7633
7634	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
7635	inline bool Type::is##Id##Type() const { \
7636	return isSpecificBuiltinType(BuiltinType::Id); \
7637	}
7638	#include "clang/Basic/OpenCLExtensionTypes.def"
7639
7640	inline bool Type::isOCLIntelSubgroupAVCType() const {
7641	#define INTEL_SUBGROUP_AVC_TYPE(ExtType, Id) \
7642	isOCLIntelSubgroupAVC##Id##Type() ||
7643	return
7644	#include "clang/Basic/OpenCLExtensionTypes.def"
7645	false; // end of boolean or operation
7646	}
7647
7648	inline bool Type::isOCLExtOpaqueType() const {
7649	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) is##Id##Type() ||
7650	return
7651	#include "clang/Basic/OpenCLExtensionTypes.def"
7652	false; // end of boolean or operation
7653	}
7654
7655	inline bool Type::isOpenCLSpecificType() const {
7656	return isSamplerT() || isEventT() || isImageType() || isClkEventT() ||
7657	isQueueT() || isReserveIDT() || isPipeType() || isOCLExtOpaqueType();
7658	}
7659
7660	inline bool Type::isTemplateTypeParmType() const {
7661	return isa<TemplateTypeParmType>(CanonicalType);
7662	}
7663
7664	inline bool Type::isSpecificBuiltinType(unsigned K) const {
7665	if (const BuiltinType *BT = getAs<BuiltinType>()) {
7666	return BT->getKind() == static_cast<BuiltinType::Kind>(K);
7667	}
7668	return false;
7669	}
7670
7671	inline bool Type::isPlaceholderType() const {
7672	if (const auto *BT = dyn_cast<BuiltinType>(this))
7673	return BT->isPlaceholderType();
7674	return false;
7675	}
7676
7677	inline const BuiltinType *Type::getAsPlaceholderType() const {
7678	if (const auto *BT = dyn_cast<BuiltinType>(this))
7679	if (BT->isPlaceholderType())
7680	return BT;
7681	return nullptr;
7682	}
7683
7684	inline bool Type::isSpecificPlaceholderType(unsigned K) const {
7685	assert(BuiltinType::isPlaceholderTypeKind((BuiltinType::Kind) K));
7686	return isSpecificBuiltinType(K);
7687	}
7688
7689	inline bool Type::isNonOverloadPlaceholderType() const {
7690	if (const auto *BT = dyn_cast<BuiltinType>(this))
7691	return BT->isNonOverloadPlaceholderType();
7692	return false;
7693	}
7694
7695	inline bool Type::isVoidType() const {
7696	return isSpecificBuiltinType(K: BuiltinType::Void);
7697	}
7698
7699	inline bool Type::isHalfType() const {
7700	// FIXME: Should we allow complex __fp16? Probably not.
7701	return isSpecificBuiltinType(K: BuiltinType::Half);
7702	}
7703
7704	inline bool Type::isFloat16Type() const {
7705	return isSpecificBuiltinType(K: BuiltinType::Float16);
7706	}
7707
7708	inline bool Type::isFloat32Type() const {
7709	return isSpecificBuiltinType(K: BuiltinType::Float);
7710	}
7711
7712	inline bool Type::isDoubleType() const {
7713	return isSpecificBuiltinType(K: BuiltinType::Double);
7714	}
7715
7716	inline bool Type::isBFloat16Type() const {
7717	return isSpecificBuiltinType(K: BuiltinType::BFloat16);
7718	}
7719
7720	inline bool Type::isFloat128Type() const {
7721	return isSpecificBuiltinType(K: BuiltinType::Float128);
7722	}
7723
7724	inline bool Type::isIbm128Type() const {
7725	return isSpecificBuiltinType(K: BuiltinType::Ibm128);
7726	}
7727
7728	inline bool Type::isNullPtrType() const {
7729	return isSpecificBuiltinType(K: BuiltinType::NullPtr);
7730	}
7731
7732	bool IsEnumDeclComplete(EnumDecl *);
7733	bool IsEnumDeclScoped(EnumDecl *);
7734
7735	inline bool Type::isIntegerType() const {
7736	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
7737	return BT->getKind() >= BuiltinType::Bool &&
7738	BT->getKind() <= BuiltinType::Int128;
7739	if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType)) {
7740	// Incomplete enum types are not treated as integer types.
7741	// FIXME: In C++, enum types are never integer types.
7742	return IsEnumDeclComplete(ET->getDecl()) &&
7743	!IsEnumDeclScoped(ET->getDecl());
7744	}
7745	return isBitIntType();
7746	}
7747
7748	inline bool Type::isFixedPointType() const {
7749	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
7750	return BT->getKind() >= BuiltinType::ShortAccum &&
7751	BT->getKind() <= BuiltinType::SatULongFract;
7752	}
7753	return false;
7754	}
7755
7756	inline bool Type::isFixedPointOrIntegerType() const {
7757	return isFixedPointType() || isIntegerType();
7758	}
7759
7760	inline bool Type::isConvertibleToFixedPointType() const {
7761	return isRealFloatingType() || isFixedPointOrIntegerType();
7762	}
7763
7764	inline bool Type::isSaturatedFixedPointType() const {
7765	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
7766	return BT->getKind() >= BuiltinType::SatShortAccum &&
7767	BT->getKind() <= BuiltinType::SatULongFract;
7768	}
7769	return false;
7770	}
7771
7772	inline bool Type::isUnsaturatedFixedPointType() const {
7773	return isFixedPointType() && !isSaturatedFixedPointType();
7774	}
7775
7776	inline bool Type::isSignedFixedPointType() const {
7777	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
7778	return ((BT->getKind() >= BuiltinType::ShortAccum &&
7779	BT->getKind() <= BuiltinType::LongAccum) ||
7780	(BT->getKind() >= BuiltinType::ShortFract &&
7781	BT->getKind() <= BuiltinType::LongFract) ||
7782	(BT->getKind() >= BuiltinType::SatShortAccum &&
7783	BT->getKind() <= BuiltinType::SatLongAccum) ||
7784	(BT->getKind() >= BuiltinType::SatShortFract &&
7785	BT->getKind() <= BuiltinType::SatLongFract));
7786	}
7787	return false;
7788	}
7789
7790	inline bool Type::isUnsignedFixedPointType() const {
7791	return isFixedPointType() && !isSignedFixedPointType();
7792	}
7793
7794	inline bool Type::isScalarType() const {
7795	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
7796	return BT->getKind() > BuiltinType::Void &&
7797	BT->getKind() <= BuiltinType::NullPtr;
7798	if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType))
7799	// Enums are scalar types, but only if they are defined. Incomplete enums
7800	// are not treated as scalar types.
7801	return IsEnumDeclComplete(ET->getDecl());
7802	return isa<PointerType>(CanonicalType) ||
7803	isa<BlockPointerType>(CanonicalType) ||
7804	isa<MemberPointerType>(CanonicalType) ||
7805	isa<ComplexType>(CanonicalType) ||
7806	isa<ObjCObjectPointerType>(CanonicalType) ||
7807	isBitIntType();
7808	}
7809
7810	inline bool Type::isIntegralOrEnumerationType() const {
7811	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
7812	return BT->getKind() >= BuiltinType::Bool &&
7813	BT->getKind() <= BuiltinType::Int128;
7814
7815	// Check for a complete enum type; incomplete enum types are not properly an
7816	// enumeration type in the sense required here.
7817	if (const auto *ET = dyn_cast<EnumType>(CanonicalType))
7818	return IsEnumDeclComplete(ET->getDecl());
7819
7820	return isBitIntType();
7821	}
7822
7823	inline bool Type::isBooleanType() const {
7824	if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
7825	return BT->getKind() == BuiltinType::Bool;
7826	return false;
7827	}
7828
7829	inline bool Type::isUndeducedType() const {
7830	auto *DT = getContainedDeducedType();
7831	return DT && !DT->isDeduced();
7832	}
7833
7834	/// Determines whether this is a type for which one can define
7835	/// an overloaded operator.
7836	inline bool Type::isOverloadableType() const {
7837	return isDependentType() || isRecordType() || isEnumeralType();
7838	}
7839
7840	/// Determines whether this type is written as a typedef-name.
7841	inline bool Type::isTypedefNameType() const {
7842	if (getAs<TypedefType>())
7843	return true;
7844	if (auto *TST = getAs<TemplateSpecializationType>())
7845	return TST->isTypeAlias();
7846	return false;
7847	}
7848
7849	/// Determines whether this type can decay to a pointer type.
7850	inline bool Type::canDecayToPointerType() const {
7851	return isFunctionType() || (isArrayType() && !isArrayParameterType());
7852	}
7853
7854	inline bool Type::hasPointerRepresentation() const {
7855	return (isPointerType() || isReferenceType() || isBlockPointerType() ||
7856	isObjCObjectPointerType() || isNullPtrType());
7857	}
7858
7859	inline bool Type::hasObjCPointerRepresentation() const {
7860	return isObjCObjectPointerType();
7861	}
7862
7863	inline const Type *Type::getBaseElementTypeUnsafe() const {
7864	const Type *type = this;
7865	while (const ArrayType *arrayType = type->getAsArrayTypeUnsafe())
7866	type = arrayType->getElementType().getTypePtr();
7867	return type;
7868	}
7869
7870	inline const Type *Type::getPointeeOrArrayElementType() const {
7871	const Type *type = this;
7872	if (type->isAnyPointerType())
7873	return type->getPointeeType().getTypePtr();
7874	else if (type->isArrayType())
7875	return type->getBaseElementTypeUnsafe();
7876	return type;
7877	}
7878	/// Insertion operator for partial diagnostics. This allows sending adress
7879	/// spaces into a diagnostic with <<.
7880	inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
7881	LangAS AS) {
7882	PD.AddTaggedVal(V: llvm::to_underlying(AS),
7883	Kind: DiagnosticsEngine::ArgumentKind::ak_addrspace);
7884	return PD;
7885	}
7886
7887	/// Insertion operator for partial diagnostics. This allows sending Qualifiers
7888	/// into a diagnostic with <<.
7889	inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
7890	Qualifiers Q) {
7891	PD.AddTaggedVal(V: Q.getAsOpaqueValue(),
7892	Kind: DiagnosticsEngine::ArgumentKind::ak_qual);
7893	return PD;
7894	}
7895
7896	/// Insertion operator for partial diagnostics. This allows sending QualType's
7897	/// into a diagnostic with <<.
7898	inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
7899	QualType T) {
7900	PD.AddTaggedVal(V: reinterpret_cast<uint64_t>(T.getAsOpaquePtr()),
7901	Kind: DiagnosticsEngine::ak_qualtype);
7902	return PD;
7903	}
7904
7905	// Helper class template that is used by Type::getAs to ensure that one does
7906	// not try to look through a qualified type to get to an array type.
7907	template <typename T>
7908	using TypeIsArrayType =
7909	std::integral_constant<bool, std::is_same<T, ArrayType>::value ||
7910	std::is_base_of<ArrayType, T>::value>;
7911
7912	// Member-template getAs<specific type>'.
7913	template <typename T> const T *Type::getAs() const {
7914	static_assert(!TypeIsArrayType<T>::value,
7915	"ArrayType cannot be used with getAs!");
7916
7917	// If this is directly a T type, return it.
7918	if (const auto *Ty = dyn_cast<T>(this))
7919	return Ty;
7920
7921	// If the canonical form of this type isn't the right kind, reject it.
7922	if (!isa<T>(CanonicalType))
7923	return nullptr;
7924
7925	// If this is a typedef for the type, strip the typedef off without
7926	// losing all typedef information.
7927	return cast<T>(getUnqualifiedDesugaredType());
7928	}
7929
7930	template <typename T> const T *Type::getAsAdjusted() const {
7931	static_assert(!TypeIsArrayType<T>::value, "ArrayType cannot be used with getAsAdjusted!");
7932
7933	// If this is directly a T type, return it.
7934	if (const auto *Ty = dyn_cast<T>(this))
7935	return Ty;
7936
7937	// If the canonical form of this type isn't the right kind, reject it.
7938	if (!isa<T>(CanonicalType))
7939	return nullptr;
7940
7941	// Strip off type adjustments that do not modify the underlying nature of the
7942	// type.
7943	const Type *Ty = this;
7944	while (Ty) {
7945	if (const auto *A = dyn_cast<AttributedType>(Ty))
7946	Ty = A->getModifiedType().getTypePtr();
7947	else if (const auto *A = dyn_cast<BTFTagAttributedType>(Ty))
7948	Ty = A->getWrappedType().getTypePtr();
7949	else if (const auto *E = dyn_cast<ElaboratedType>(Ty))
7950	Ty = E->desugar().getTypePtr();
7951	else if (const auto *P = dyn_cast<ParenType>(Ty))
7952	Ty = P->desugar().getTypePtr();
7953	else if (const auto *A = dyn_cast<AdjustedType>(Ty))
7954	Ty = A->desugar().getTypePtr();
7955	else if (const auto *M = dyn_cast<MacroQualifiedType>(Ty))
7956	Ty = M->desugar().getTypePtr();
7957	else
7958	break;
7959	}
7960
7961	// Just because the canonical type is correct does not mean we can use cast<>,
7962	// since we may not have stripped off all the sugar down to the base type.
7963	return dyn_cast<T>(Ty);
7964	}
7965
7966	inline const ArrayType *Type::getAsArrayTypeUnsafe() const {
7967	// If this is directly an array type, return it.
7968	if (const auto *arr = dyn_cast<ArrayType>(this))
7969	return arr;
7970
7971	// If the canonical form of this type isn't the right kind, reject it.
7972	if (!isa<ArrayType>(CanonicalType))
7973	return nullptr;
7974
7975	// If this is a typedef for the type, strip the typedef off without
7976	// losing all typedef information.
7977	return cast<ArrayType>(getUnqualifiedDesugaredType());
7978	}
7979
7980	template <typename T> const T *Type::castAs() const {
7981	static_assert(!TypeIsArrayType<T>::value,
7982	"ArrayType cannot be used with castAs!");
7983
7984	if (const auto *ty = dyn_cast<T>(this)) return ty;
7985	assert(isa<T>(CanonicalType));
7986	return cast<T>(getUnqualifiedDesugaredType());
7987	}
7988
7989	inline const ArrayType *Type::castAsArrayTypeUnsafe() const {
7990	assert(isa<ArrayType>(CanonicalType));
7991	if (const auto *arr = dyn_cast<ArrayType>(this)) return arr;
7992	return cast<ArrayType>(getUnqualifiedDesugaredType());
7993	}
7994
7995	DecayedType::DecayedType(QualType OriginalType, QualType DecayedPtr,
7996	QualType CanonicalPtr)
7997	: AdjustedType(Decayed, OriginalType, DecayedPtr, CanonicalPtr) {
7998	#ifndef NDEBUG
7999	QualType Adjusted = getAdjustedType();
8000	(void)AttributedType::stripOuterNullability(Adjusted);
8001	assert(isa<PointerType>(Adjusted));
8002	#endif
8003	}
8004
8005	QualType DecayedType::getPointeeType() const {
8006	QualType Decayed = getDecayedType();
8007	(void)AttributedType::stripOuterNullability(Decayed);
8008	return cast<PointerType>(Decayed)->getPointeeType();
8009	}
8010
8011	// Get the decimal string representation of a fixed point type, represented
8012	// as a scaled integer.
8013	// TODO: At some point, we should change the arguments to instead just accept an
8014	// APFixedPoint instead of APSInt and scale.
8015	void FixedPointValueToString(SmallVectorImpl<char> &Str, llvm::APSInt Val,
8016	unsigned Scale);
8017
8018	} // namespace clang
8019
8020	#endif // LLVM_CLANG_AST_TYPE_H
8021