Type.h source code [clang/include/clang/AST/Type.h]

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: getAsArrayType 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 + 4100]' 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());