clang  14.0.0git
Type.h
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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 
22 #include "clang/AST/TemplateName.h"
24 #include "clang/Basic/AttrKinds.h"
25 #include "clang/Basic/Diagnostic.h"
27 #include "clang/Basic/LLVM.h"
28 #include "clang/Basic/Linkage.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/None.h"
38 #include "llvm/ADT/Optional.h"
39 #include "llvm/ADT/PointerIntPair.h"
40 #include "llvm/ADT/PointerUnion.h"
41 #include "llvm/ADT/StringRef.h"
42 #include "llvm/ADT/Twine.h"
43 #include "llvm/ADT/iterator_range.h"
44 #include "llvm/Support/Casting.h"
45 #include "llvm/Support/Compiler.h"
46 #include "llvm/Support/ErrorHandling.h"
47 #include "llvm/Support/PointerLikeTypeTraits.h"
48 #include "llvm/Support/TrailingObjects.h"
49 #include "llvm/Support/type_traits.h"
50 #include <cassert>
51 #include <cstddef>
52 #include <cstdint>
53 #include <cstring>
54 #include <string>
55 #include <type_traits>
56 #include <utility>
57 
58 namespace clang {
59 
60 class ExtQuals;
61 class QualType;
62 class ConceptDecl;
63 class TagDecl;
64 class TemplateParameterList;
65 class Type;
66 
67 enum {
70 };
71 
72 namespace serialization {
73  template <class T> class AbstractTypeReader;
74  template <class T> class AbstractTypeWriter;
75 }
76 
77 } // namespace clang
78 
79 namespace llvm {
80 
81  template <typename T>
82  struct PointerLikeTypeTraits;
83  template<>
85  static inline void *getAsVoidPointer(::clang::Type *P) { return P; }
86 
88  return static_cast< ::clang::Type*>(P);
89  }
90 
91  static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
92  };
93 
94  template<>
96  static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }
97 
98  static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
99  return static_cast< ::clang::ExtQuals*>(P);
100  }
101 
102  static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
103  };
104 
105 } // namespace llvm
106 
107 namespace clang {
108 
109 class ASTContext;
110 template <typename> class CanQual;
111 class CXXRecordDecl;
112 class DeclContext;
113 class EnumDecl;
114 class Expr;
115 class ExtQualsTypeCommonBase;
116 class FunctionDecl;
117 class IdentifierInfo;
118 class NamedDecl;
119 class ObjCInterfaceDecl;
120 class ObjCProtocolDecl;
121 class ObjCTypeParamDecl;
122 struct PrintingPolicy;
123 class RecordDecl;
124 class Stmt;
125 class TagDecl;
126 class TemplateArgument;
127 class TemplateArgumentListInfo;
128 class TemplateArgumentLoc;
129 class TemplateTypeParmDecl;
130 class TypedefNameDecl;
131 class UnresolvedUsingTypenameDecl;
132 class UsingShadowDecl;
133 
134 using CanQualType = CanQual<Type>;
135 
136 // Provide forward declarations for all of the *Type classes.
137 #define TYPE(Class, Base) class Class##Type;
138 #include "clang/AST/TypeNodes.inc"
139 
140 /// The collection of all-type qualifiers we support.
141 /// Clang supports five independent qualifiers:
142 /// * C99: const, volatile, and restrict
143 /// * MS: __unaligned
144 /// * Embedded C (TR18037): address spaces
145 /// * Objective C: the GC attributes (none, weak, or strong)
146 class Qualifiers {
147 public:
148  enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
149  Const = 0x1,
150  Restrict = 0x2,
151  Volatile = 0x4,
153  };
154 
155  enum GC {
156  GCNone = 0,
159  };
160 
162  /// There is no lifetime qualification on this type.
164 
165  /// This object can be modified without requiring retains or
166  /// releases.
168 
169  /// Assigning into this object requires the old value to be
170  /// released and the new value to be retained. The timing of the
171  /// release of the old value is inexact: it may be moved to
172  /// immediately after the last known point where the value is
173  /// live.
175 
176  /// Reading or writing from this object requires a barrier call.
178 
179  /// Assigning into this object requires a lifetime extension.
181  };
182 
183  enum {
184  /// The maximum supported address space number.
185  /// 23 bits should be enough for anyone.
186  MaxAddressSpace = 0x7fffffu,
187 
188  /// The width of the "fast" qualifier mask.
190 
191  /// The fast qualifier mask.
192  FastMask = (1 << FastWidth) - 1
193  };
194 
195  /// Returns the common set of qualifiers while removing them from
196  /// the given sets.
198  // If both are only CVR-qualified, bit operations are sufficient.
199  if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
200  Qualifiers Q;
201  Q.Mask = L.Mask & R.Mask;
202  L.Mask &= ~Q.Mask;
203  R.Mask &= ~Q.Mask;
204  return Q;
205  }
206 
207  Qualifiers Q;
208  unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
209  Q.addCVRQualifiers(CommonCRV);
210  L.removeCVRQualifiers(CommonCRV);
211  R.removeCVRQualifiers(CommonCRV);
212 
213  if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
215  L.removeObjCGCAttr();
216  R.removeObjCGCAttr();
217  }
218 
219  if (L.getObjCLifetime() == R.getObjCLifetime()) {
221  L.removeObjCLifetime();
222  R.removeObjCLifetime();
223  }
224 
225  if (L.getAddressSpace() == R.getAddressSpace()) {
227  L.removeAddressSpace();
228  R.removeAddressSpace();
229  }
230  return Q;
231  }
232 
233  static Qualifiers fromFastMask(unsigned Mask) {
234  Qualifiers Qs;
235  Qs.addFastQualifiers(Mask);
236  return Qs;
237  }
238 
239  static Qualifiers fromCVRMask(unsigned CVR) {
240  Qualifiers Qs;
241  Qs.addCVRQualifiers(CVR);
242  return Qs;
243  }
244 
245  static Qualifiers fromCVRUMask(unsigned CVRU) {
246  Qualifiers Qs;
247  Qs.addCVRUQualifiers(CVRU);
248  return Qs;
249  }
250 
251  // Deserialize qualifiers from an opaque representation.
252  static Qualifiers fromOpaqueValue(unsigned opaque) {
253  Qualifiers Qs;
254  Qs.Mask = opaque;
255  return Qs;
256  }
257 
258  // Serialize these qualifiers into an opaque representation.
259  unsigned getAsOpaqueValue() const {
260  return Mask;
261  }
262 
263  bool hasConst() const { return Mask & Const; }
264  bool hasOnlyConst() const { return Mask == Const; }
265  void removeConst() { Mask &= ~Const; }
266  void addConst() { Mask |= Const; }
267 
268  bool hasVolatile() const { return Mask & Volatile; }
269  bool hasOnlyVolatile() const { return Mask == Volatile; }
270  void removeVolatile() { Mask &= ~Volatile; }
271  void addVolatile() { Mask |= Volatile; }
272 
273  bool hasRestrict() const { return Mask & Restrict; }
274  bool hasOnlyRestrict() const { return Mask == Restrict; }
275  void removeRestrict() { Mask &= ~Restrict; }
276  void addRestrict() { Mask |= Restrict; }
277 
278  bool hasCVRQualifiers() const { return getCVRQualifiers(); }
279  unsigned getCVRQualifiers() const { return Mask & CVRMask; }
280  unsigned getCVRUQualifiers() const { return Mask & (CVRMask | UMask); }
281 
282  void setCVRQualifiers(unsigned mask) {
283  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
284  Mask = (Mask & ~CVRMask) | mask;
285  }
286  void removeCVRQualifiers(unsigned mask) {
287  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
288  Mask &= ~mask;
289  }
292  }
293  void addCVRQualifiers(unsigned mask) {
294  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
295  Mask |= mask;
296  }
297  void addCVRUQualifiers(unsigned mask) {
298  assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits");
299  Mask |= mask;
300  }
301 
302  bool hasUnaligned() const { return Mask & UMask; }
303  void setUnaligned(bool flag) {
304  Mask = (Mask & ~UMask) | (flag ? UMask : 0);
305  }
306  void removeUnaligned() { Mask &= ~UMask; }
307  void addUnaligned() { Mask |= UMask; }
308 
309  bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
310  GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
312  Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
313  }
316  assert(type);
318  }
320  Qualifiers qs = *this;
321  qs.removeObjCGCAttr();
322  return qs;
323  }
325  Qualifiers qs = *this;
326  qs.removeObjCLifetime();
327  return qs;
328  }
330  Qualifiers qs = *this;
331  qs.removeAddressSpace();
332  return qs;
333  }
334 
335  bool hasObjCLifetime() const { return Mask & LifetimeMask; }
337  return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
338  }
340  Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
341  }
344  assert(type);
345  assert(!hasObjCLifetime());
346  Mask |= (type << LifetimeShift);
347  }
348 
349  /// True if the lifetime is neither None or ExplicitNone.
351  ObjCLifetime lifetime = getObjCLifetime();
352  return (lifetime > OCL_ExplicitNone);
353  }
354 
355  /// True if the lifetime is either strong or weak.
357  ObjCLifetime lifetime = getObjCLifetime();
358  return (lifetime == OCL_Strong || lifetime == OCL_Weak);
359  }
360 
361  bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
363  return static_cast<LangAS>(Mask >> AddressSpaceShift);
364  }
367  }
368  /// Get the address space attribute value to be printed by diagnostics.
370  auto Addr = getAddressSpace();
371  // This function is not supposed to be used with language specific
372  // address spaces. If that happens, the diagnostic message should consider
373  // printing the QualType instead of the address space value.
374  assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace());
375  if (Addr != LangAS::Default)
376  return toTargetAddressSpace(Addr);
377  // TODO: The diagnostic messages where Addr may be 0 should be fixed
378  // since it cannot differentiate the situation where 0 denotes the default
379  // address space or user specified __attribute__((address_space(0))).
380  return 0;
381  }
382  void setAddressSpace(LangAS space) {
383  assert((unsigned)space <= MaxAddressSpace);
384  Mask = (Mask & ~AddressSpaceMask)
385  | (((uint32_t) space) << AddressSpaceShift);
386  }
388  void addAddressSpace(LangAS space) {
389  assert(space != LangAS::Default);
390  setAddressSpace(space);
391  }
392 
393  // Fast qualifiers are those that can be allocated directly
394  // on a QualType object.
395  bool hasFastQualifiers() const { return getFastQualifiers(); }
396  unsigned getFastQualifiers() const { return Mask & FastMask; }
397  void setFastQualifiers(unsigned mask) {
398  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
399  Mask = (Mask & ~FastMask) | mask;
400  }
401  void removeFastQualifiers(unsigned mask) {
402  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
403  Mask &= ~mask;
404  }
407  }
408  void addFastQualifiers(unsigned mask) {
409  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
410  Mask |= mask;
411  }
412 
413  /// Return true if the set contains any qualifiers which require an ExtQuals
414  /// node to be allocated.
415  bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
417  Qualifiers Quals = *this;
418  Quals.setFastQualifiers(0);
419  return Quals;
420  }
421 
422  /// Return true if the set contains any qualifiers.
423  bool hasQualifiers() const { return Mask; }
424  bool empty() const { return !Mask; }
425 
426  /// Add the qualifiers from the given set to this set.
428  // If the other set doesn't have any non-boolean qualifiers, just
429  // bit-or it in.
430  if (!(Q.Mask & ~CVRMask))
431  Mask |= Q.Mask;
432  else {
433  Mask |= (Q.Mask & CVRMask);
434  if (Q.hasAddressSpace())
436  if (Q.hasObjCGCAttr())
438  if (Q.hasObjCLifetime())
440  }
441  }
442 
443  /// Remove the qualifiers from the given set from this set.
445  // If the other set doesn't have any non-boolean qualifiers, just
446  // bit-and the inverse in.
447  if (!(Q.Mask & ~CVRMask))
448  Mask &= ~Q.Mask;
449  else {
450  Mask &= ~(Q.Mask & CVRMask);
451  if (getObjCGCAttr() == Q.getObjCGCAttr())
453  if (getObjCLifetime() == Q.getObjCLifetime())
455  if (getAddressSpace() == Q.getAddressSpace())
457  }
458  }
459 
460  /// Add the qualifiers from the given set to this set, given that
461  /// they don't conflict.
463  assert(getAddressSpace() == qs.getAddressSpace() ||
464  !hasAddressSpace() || !qs.hasAddressSpace());
465  assert(getObjCGCAttr() == qs.getObjCGCAttr() ||
466  !hasObjCGCAttr() || !qs.hasObjCGCAttr());
467  assert(getObjCLifetime() == qs.getObjCLifetime() ||
468  !hasObjCLifetime() || !qs.hasObjCLifetime());
469  Mask |= qs.Mask;
470  }
471 
472  /// Returns true if address space A is equal to or a superset of B.
473  /// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
474  /// overlapping address spaces.
475  /// CL1.1 or CL1.2:
476  /// every address space is a superset of itself.
477  /// CL2.0 adds:
478  /// __generic is a superset of any address space except for __constant.
480  // Address spaces must match exactly.
481  return A == B ||
482  // Otherwise in OpenCLC v2.0 s6.5.5: every address space except
483  // for __constant can be used as __generic.
485  // We also define global_device and global_host address spaces,
486  // to distinguish global pointers allocated on host from pointers
487  // allocated on device, which are a subset of __global.
491  B == LangAS::sycl_global_host)) ||
492  // Consider pointer size address spaces to be equivalent to default.
493  ((isPtrSizeAddressSpace(A) || A == LangAS::Default) &&
494  (isPtrSizeAddressSpace(B) || B == LangAS::Default)) ||
495  // Default is a superset of SYCL address spaces.
496  (A == LangAS::Default &&
499  B == LangAS::sycl_global_host)) ||
500  // In HIP device compilation, any cuda address space is allowed
501  // to implicitly cast into the default address space.
502  (A == LangAS::Default &&
504  B == LangAS::cuda_shared));
505  }
506 
507  /// Returns true if the address space in these qualifiers is equal to or
508  /// a superset of the address space in the argument qualifiers.
511  }
512 
513  /// Determines if these qualifiers compatibly include another set.
514  /// Generally this answers the question of whether an object with the other
515  /// qualifiers can be safely used as an object with these qualifiers.
516  bool compatiblyIncludes(Qualifiers other) const {
517  return isAddressSpaceSupersetOf(other) &&
518  // ObjC GC qualifiers can match, be added, or be removed, but can't
519  // be changed.
520  (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
521  !other.hasObjCGCAttr()) &&
522  // ObjC lifetime qualifiers must match exactly.
523  getObjCLifetime() == other.getObjCLifetime() &&
524  // CVR qualifiers may subset.
525  (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
526  // U qualifier may superset.
527  (!other.hasUnaligned() || hasUnaligned());
528  }
529 
530  /// Determines if these qualifiers compatibly include another set of
531  /// qualifiers from the narrow perspective of Objective-C ARC lifetime.
532  ///
533  /// One set of Objective-C lifetime qualifiers compatibly includes the other
534  /// if the lifetime qualifiers match, or if both are non-__weak and the
535  /// including set also contains the 'const' qualifier, or both are non-__weak
536  /// and one is None (which can only happen in non-ARC modes).
538  if (getObjCLifetime() == other.getObjCLifetime())
539  return true;
540 
541  if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
542  return false;
543 
544  if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
545  return true;
546 
547  return hasConst();
548  }
549 
550  /// Determine whether this set of qualifiers is a strict superset of
551  /// another set of qualifiers, not considering qualifier compatibility.
552  bool isStrictSupersetOf(Qualifiers Other) const;
553 
554  bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
555  bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
556 
557  explicit operator bool() const { return hasQualifiers(); }
558 
560  addQualifiers(R);
561  return *this;
562  }
563 
564  // Union two qualifier sets. If an enumerated qualifier appears
565  // in both sets, use the one from the right.
567  L += R;
568  return L;
569  }
570 
572  removeQualifiers(R);
573  return *this;
574  }
575 
576  /// Compute the difference between two qualifier sets.
578  L -= R;
579  return L;
580  }
581 
582  std::string getAsString() const;
583  std::string getAsString(const PrintingPolicy &Policy) const;
584 
586 
587  bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
588  void print(raw_ostream &OS, const PrintingPolicy &Policy,
589  bool appendSpaceIfNonEmpty = false) const;
590 
591  void Profile(llvm::FoldingSetNodeID &ID) const {
592  ID.AddInteger(Mask);
593  }
594 
595 private:
596  // bits: |0 1 2|3|4 .. 5|6 .. 8|9 ... 31|
597  // |C R V|U|GCAttr|Lifetime|AddressSpace|
598  uint32_t Mask = 0;
599 
600  static const uint32_t UMask = 0x8;
601  static const uint32_t UShift = 3;
602  static const uint32_t GCAttrMask = 0x30;
603  static const uint32_t GCAttrShift = 4;
604  static const uint32_t LifetimeMask = 0x1C0;
605  static const uint32_t LifetimeShift = 6;
606  static const uint32_t AddressSpaceMask =
607  ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
608  static const uint32_t AddressSpaceShift = 9;
609 };
610 
611 /// A std::pair-like structure for storing a qualified type split
612 /// into its local qualifiers and its locally-unqualified type.
614  /// The locally-unqualified type.
615  const Type *Ty = nullptr;
616 
617  /// The local qualifiers.
619 
620  SplitQualType() = default;
621  SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
622 
623  SplitQualType getSingleStepDesugaredType() const; // end of this file
624 
625  // Make std::tie work.
626  std::pair<const Type *,Qualifiers> asPair() const {
627  return std::pair<const Type *, Qualifiers>(Ty, Quals);
628  }
629 
631  return a.Ty == b.Ty && a.Quals == b.Quals;
632  }
634  return a.Ty != b.Ty || a.Quals != b.Quals;
635  }
636 };
637 
638 /// The kind of type we are substituting Objective-C type arguments into.
639 ///
640 /// The kind of substitution affects the replacement of type parameters when
641 /// no concrete type information is provided, e.g., when dealing with an
642 /// unspecialized type.
644  /// An ordinary type.
645  Ordinary,
646 
647  /// The result type of a method or function.
648  Result,
649 
650  /// The parameter type of a method or function.
651  Parameter,
652 
653  /// The type of a property.
654  Property,
655 
656  /// The superclass of a type.
657  Superclass,
658 };
659 
660 /// A (possibly-)qualified type.
661 ///
662 /// For efficiency, we don't store CV-qualified types as nodes on their
663 /// own: instead each reference to a type stores the qualifiers. This
664 /// greatly reduces the number of nodes we need to allocate for types (for
665 /// example we only need one for 'int', 'const int', 'volatile int',
666 /// 'const volatile int', etc).
667 ///
668 /// As an added efficiency bonus, instead of making this a pair, we
669 /// just store the two bits we care about in the low bits of the
670 /// pointer. To handle the packing/unpacking, we make QualType be a
671 /// simple wrapper class that acts like a smart pointer. A third bit
672 /// indicates whether there are extended qualifiers present, in which
673 /// case the pointer points to a special structure.
674 class QualType {
675  friend class QualifierCollector;
676 
677  // Thankfully, these are efficiently composable.
678  llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
680 
681  const ExtQuals *getExtQualsUnsafe() const {
682  return Value.getPointer().get<const ExtQuals*>();
683  }
684 
685  const Type *getTypePtrUnsafe() const {
686  return Value.getPointer().get<const Type*>();
687  }
688 
689  const ExtQualsTypeCommonBase *getCommonPtr() const {
690  assert(!isNull() && "Cannot retrieve a NULL type pointer");
691  auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
692  CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
693  return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
694  }
695 
696 public:
697  QualType() = default;
698  QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
699  QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
700 
701  unsigned getLocalFastQualifiers() const { return Value.getInt(); }
702  void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
703 
704  /// Retrieves a pointer to the underlying (unqualified) type.
705  ///
706  /// This function requires that the type not be NULL. If the type might be
707  /// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
708  const Type *getTypePtr() const;
709 
710  const Type *getTypePtrOrNull() const;
711 
712  /// Retrieves a pointer to the name of the base type.
713  const IdentifierInfo *getBaseTypeIdentifier() const;
714 
715  /// Divides a QualType into its unqualified type and a set of local
716  /// qualifiers.
717  SplitQualType split() const;
718 
719  void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
720 
721  static QualType getFromOpaquePtr(const void *Ptr) {
722  QualType T;
723  T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
724  return T;
725  }
726 
727  const Type &operator*() const {
728  return *getTypePtr();
729  }
730 
731  const Type *operator->() const {
732  return getTypePtr();
733  }
734 
735  bool isCanonical() const;
736  bool isCanonicalAsParam() const;
737 
738  /// Return true if this QualType doesn't point to a type yet.
739  bool isNull() const {
740  return Value.getPointer().isNull();
741  }
742 
743  /// Determine whether this particular QualType instance has the
744  /// "const" qualifier set, without looking through typedefs that may have
745  /// added "const" at a different level.
746  bool isLocalConstQualified() const {
748  }
749 
750  /// Determine whether this type is const-qualified.
751  bool isConstQualified() const;
752 
753  /// Determine whether this particular QualType instance has the
754  /// "restrict" qualifier set, without looking through typedefs that may have
755  /// added "restrict" at a different level.
758  }
759 
760  /// Determine whether this type is restrict-qualified.
761  bool isRestrictQualified() const;
762 
763  /// Determine whether this particular QualType instance has the
764  /// "volatile" qualifier set, without looking through typedefs that may have
765  /// added "volatile" at a different level.
768  }
769 
770  /// Determine whether this type is volatile-qualified.
771  bool isVolatileQualified() const;
772 
773  /// Determine whether this particular QualType instance has any
774  /// qualifiers, without looking through any typedefs that might add
775  /// qualifiers at a different level.
776  bool hasLocalQualifiers() const {
778  }
779 
780  /// Determine whether this type has any qualifiers.
781  bool hasQualifiers() const;
782 
783  /// Determine whether this particular QualType instance has any
784  /// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
785  /// instance.
787  return Value.getPointer().is<const ExtQuals*>();
788  }
789 
790  /// Retrieve the set of qualifiers local to this particular QualType
791  /// instance, not including any qualifiers acquired through typedefs or
792  /// other sugar.
794 
795  /// Retrieve the set of qualifiers applied to this type.
796  Qualifiers getQualifiers() const;
797 
798  /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
799  /// local to this particular QualType instance, not including any qualifiers
800  /// acquired through typedefs or other sugar.
801  unsigned getLocalCVRQualifiers() const {
802  return getLocalFastQualifiers();
803  }
804 
805  /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
806  /// applied to this type.
807  unsigned getCVRQualifiers() const;
808 
809  bool isConstant(const ASTContext& Ctx) const {
810  return QualType::isConstant(*this, Ctx);
811  }
812 
813  /// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
814  bool isPODType(const ASTContext &Context) const;
815 
816  /// Return true if this is a POD type according to the rules of the C++98
817  /// standard, regardless of the current compilation's language.
818  bool isCXX98PODType(const ASTContext &Context) const;
819 
820  /// Return true if this is a POD type according to the more relaxed rules
821  /// of the C++11 standard, regardless of the current compilation's language.
822  /// (C++0x [basic.types]p9). Note that, unlike
823  /// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
824  bool isCXX11PODType(const ASTContext &Context) const;
825 
826  /// Return true if this is a trivial type per (C++0x [basic.types]p9)
827  bool isTrivialType(const ASTContext &Context) const;
828 
829  /// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
830  bool isTriviallyCopyableType(const ASTContext &Context) const;
831 
832 
833  /// Returns true if it is a class and it might be dynamic.
834  bool mayBeDynamicClass() const;
835 
836  /// Returns true if it is not a class or if the class might not be dynamic.
837  bool mayBeNotDynamicClass() const;
838 
839  // Don't promise in the API that anything besides 'const' can be
840  // easily added.
841 
842  /// Add the `const` type qualifier to this QualType.
843  void addConst() {
845  }
846  QualType withConst() const {
848  }
849 
850  /// Add the `volatile` type qualifier to this QualType.
851  void addVolatile() {
853  }
856  }
857 
858  /// Add the `restrict` qualifier to this QualType.
859  void addRestrict() {
861  }
864  }
865 
866  QualType withCVRQualifiers(unsigned CVR) const {
867  return withFastQualifiers(CVR);
868  }
869 
870  void addFastQualifiers(unsigned TQs) {
871  assert(!(TQs & ~Qualifiers::FastMask)
872  && "non-fast qualifier bits set in mask!");
873  Value.setInt(Value.getInt() | TQs);
874  }
875 
876  void removeLocalConst();
877  void removeLocalVolatile();
878  void removeLocalRestrict();
879  void removeLocalCVRQualifiers(unsigned Mask);
880 
881  void removeLocalFastQualifiers() { Value.setInt(0); }
882  void removeLocalFastQualifiers(unsigned Mask) {
883  assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers");
884  Value.setInt(Value.getInt() & ~Mask);
885  }
886 
887  // Creates a type with the given qualifiers in addition to any
888  // qualifiers already on this type.
889  QualType withFastQualifiers(unsigned TQs) const {
890  QualType T = *this;
891  T.addFastQualifiers(TQs);
892  return T;
893  }
894 
895  // Creates a type with exactly the given fast qualifiers, removing
896  // any existing fast qualifiers.
899  }
900 
901  // Removes fast qualifiers, but leaves any extended qualifiers in place.
903  QualType T = *this;
905  return T;
906  }
907 
908  QualType getCanonicalType() const;
909 
910  /// Return this type with all of the instance-specific qualifiers
911  /// removed, but without removing any qualifiers that may have been applied
912  /// through typedefs.
914 
915  /// Retrieve the unqualified variant of the given type,
916  /// removing as little sugar as possible.
917  ///
918  /// This routine looks through various kinds of sugar to find the
919  /// least-desugared type that is unqualified. For example, given:
920  ///
921  /// \code
922  /// typedef int Integer;
923  /// typedef const Integer CInteger;
924  /// typedef CInteger DifferenceType;
925  /// \endcode
926  ///
927  /// Executing \c getUnqualifiedType() on the type \c DifferenceType will
928  /// desugar until we hit the type \c Integer, which has no qualifiers on it.
929  ///
930  /// The resulting type might still be qualified if it's sugar for an array
931  /// type. To strip qualifiers even from within a sugared array type, use
932  /// ASTContext::getUnqualifiedArrayType.
933  inline QualType getUnqualifiedType() const;
934 
935  /// Retrieve the unqualified variant of the given type, removing as little
936  /// sugar as possible.
937  ///
938  /// Like getUnqualifiedType(), but also returns the set of
939  /// qualifiers that were built up.
940  ///
941  /// The resulting type might still be qualified if it's sugar for an array
942  /// type. To strip qualifiers even from within a sugared array type, use
943  /// ASTContext::getUnqualifiedArrayType.
944  inline SplitQualType getSplitUnqualifiedType() const;
945 
946  /// Determine whether this type is more qualified than the other
947  /// given type, requiring exact equality for non-CVR qualifiers.
948  bool isMoreQualifiedThan(QualType Other) const;
949 
950  /// Determine whether this type is at least as qualified as the other
951  /// given type, requiring exact equality for non-CVR qualifiers.
952  bool isAtLeastAsQualifiedAs(QualType Other) const;
953 
955 
956  /// Determine the type of a (typically non-lvalue) expression with the
957  /// specified result type.
958  ///
959  /// This routine should be used for expressions for which the return type is
960  /// explicitly specified (e.g., in a cast or call) and isn't necessarily
961  /// an lvalue. It removes a top-level reference (since there are no
962  /// expressions of reference type) and deletes top-level cvr-qualifiers
963  /// from non-class types (in C++) or all types (in C).
964  QualType getNonLValueExprType(const ASTContext &Context) const;
965 
966  /// Remove an outer pack expansion type (if any) from this type. Used as part
967  /// of converting the type of a declaration to the type of an expression that
968  /// references that expression. It's meaningless for an expression to have a
969  /// pack expansion type.
971 
972  /// Return the specified type with any "sugar" removed from
973  /// the type. This takes off typedefs, typeof's etc. If the outer level of
974  /// the type is already concrete, it returns it unmodified. This is similar
975  /// to getting the canonical type, but it doesn't remove *all* typedefs. For
976  /// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
977  /// concrete.
978  ///
979  /// Qualifiers are left in place.
980  QualType getDesugaredType(const ASTContext &Context) const {
981  return getDesugaredType(*this, Context);
982  }
983 
985  return getSplitDesugaredType(*this);
986  }
987 
988  /// Return the specified type with one level of "sugar" removed from
989  /// the type.
990  ///
991  /// This routine takes off the first typedef, typeof, etc. If the outer level
992  /// of the type is already concrete, it returns it unmodified.
994  return getSingleStepDesugaredTypeImpl(*this, Context);
995  }
996 
997  /// Returns the specified type after dropping any
998  /// outer-level parentheses.
1000  if (isa<ParenType>(*this))
1001  return QualType::IgnoreParens(*this);
1002  return *this;
1003  }
1004 
1005  /// Indicate whether the specified types and qualifiers are identical.
1006  friend bool operator==(const QualType &LHS, const QualType &RHS) {
1007  return LHS.Value == RHS.Value;
1008  }
1009  friend bool operator!=(const QualType &LHS, const QualType &RHS) {
1010  return LHS.Value != RHS.Value;
1011  }
1012  friend bool operator<(const QualType &LHS, const QualType &RHS) {
1013  return LHS.Value < RHS.Value;
1014  }
1015 
1017  const PrintingPolicy &Policy) {
1018  return getAsString(split.Ty, split.Quals, Policy);
1019  }
1020  static std::string getAsString(const Type *ty, Qualifiers qs,
1021  const PrintingPolicy &Policy);
1022 
1023  std::string getAsString() const;
1024  std::string getAsString(const PrintingPolicy &Policy) const;
1025 
1026  void print(raw_ostream &OS, const PrintingPolicy &Policy,
1027  const Twine &PlaceHolder = Twine(),
1028  unsigned Indentation = 0) const;
1029 
1030  static void print(SplitQualType split, raw_ostream &OS,
1031  const PrintingPolicy &policy, const Twine &PlaceHolder,
1032  unsigned Indentation = 0) {
1033  return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
1034  }
1035 
1036  static void print(const Type *ty, Qualifiers qs,
1037  raw_ostream &OS, const PrintingPolicy &policy,
1038  const Twine &PlaceHolder,
1039  unsigned Indentation = 0);
1040 
1041  void getAsStringInternal(std::string &Str,
1042  const PrintingPolicy &Policy) const;
1043 
1045  const PrintingPolicy &policy) {
1046  return getAsStringInternal(split.Ty, split.Quals, out, policy);
1047  }
1048 
1049  static void getAsStringInternal(const Type *ty, Qualifiers qs,
1050  std::string &out,
1051  const PrintingPolicy &policy);
1052 
1054  const QualType &T;
1055  const PrintingPolicy &Policy;
1056  const Twine &PlaceHolder;
1057  unsigned Indentation;
1058 
1059  public:
1061  const Twine &PlaceHolder, unsigned Indentation)
1062  : T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1063  Indentation(Indentation) {}
1064 
1065  friend raw_ostream &operator<<(raw_ostream &OS,
1066  const StreamedQualTypeHelper &SQT) {
1067  SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
1068  return OS;
1069  }
1070  };
1071 
1073  const Twine &PlaceHolder = Twine(),
1074  unsigned Indentation = 0) const {
1075  return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1076  }
1077 
1078  void dump(const char *s) const;
1079  void dump() const;
1080  void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
1081 
1082  void Profile(llvm::FoldingSetNodeID &ID) const {
1083  ID.AddPointer(getAsOpaquePtr());
1084  }
1085 
1086  /// Check if this type has any address space qualifier.
1087  inline bool hasAddressSpace() const;
1088 
1089  /// Return the address space of this type.
1090  inline LangAS getAddressSpace() const;
1091 
1092  /// Returns true if address space qualifiers overlap with T address space
1093  /// qualifiers.
1094  /// OpenCL C defines conversion rules for pointers to different address spaces
1095  /// and notion of overlapping address spaces.
1096  /// CL1.1 or CL1.2:
1097  /// address spaces overlap iff they are they same.
1098  /// OpenCL C v2.0 s6.5.5 adds:
1099  /// __generic overlaps with any address space except for __constant.
1101  Qualifiers Q = getQualifiers();
1102  Qualifiers TQ = T.getQualifiers();
1103  // Address spaces overlap if at least one of them is a superset of another
1104  return Q.isAddressSpaceSupersetOf(TQ) || TQ.isAddressSpaceSupersetOf(Q);
1105  }
1106 
1107  /// Returns gc attribute of this type.
1108  inline Qualifiers::GC getObjCGCAttr() const;
1109 
1110  /// true when Type is objc's weak.
1111  bool isObjCGCWeak() const {
1112  return getObjCGCAttr() == Qualifiers::Weak;
1113  }
1114 
1115  /// true when Type is objc's strong.
1116  bool isObjCGCStrong() const {
1117  return getObjCGCAttr() == Qualifiers::Strong;
1118  }
1119 
1120  /// Returns lifetime attribute of this type.
1122  return getQualifiers().getObjCLifetime();
1123  }
1124 
1127  }
1128 
1131  }
1132 
1133  // true when Type is objc's weak and weak is enabled but ARC isn't.
1134  bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1135 
1137  /// The type does not fall into any of the following categories. Note that
1138  /// this case is zero-valued so that values of this enum can be used as a
1139  /// boolean condition for non-triviality.
1141 
1142  /// The type is an Objective-C retainable pointer type that is qualified
1143  /// with the ARC __strong qualifier.
1145 
1146  /// The type is an Objective-C retainable pointer type that is qualified
1147  /// with the ARC __weak qualifier.
1149 
1150  /// The type is a struct containing a field whose type is not PCK_Trivial.
1152  };
1153 
1154  /// Functions to query basic properties of non-trivial C struct types.
1155 
1156  /// Check if this is a non-trivial type that would cause a C struct
1157  /// transitively containing this type to be non-trivial to default initialize
1158  /// and return the kind.
1161 
1163  /// The type does not fall into any of the following categories. Note that
1164  /// this case is zero-valued so that values of this enum can be used as a
1165  /// boolean condition for non-triviality.
1167 
1168  /// The type would be trivial except that it is volatile-qualified. Types
1169  /// that fall into one of the other non-trivial cases may additionally be
1170  /// volatile-qualified.
1172 
1173  /// The type is an Objective-C retainable pointer type that is qualified
1174  /// with the ARC __strong qualifier.
1176 
1177  /// The type is an Objective-C retainable pointer type that is qualified
1178  /// with the ARC __weak qualifier.
1180 
1181  /// The type is a struct containing a field whose type is neither
1182  /// PCK_Trivial nor PCK_VolatileTrivial.
1183  /// Note that a C++ struct type does not necessarily match this; C++ copying
1184  /// semantics are too complex to express here, in part because they depend
1185  /// on the exact constructor or assignment operator that is chosen by
1186  /// overload resolution to do the copy.
1188  };
1189 
1190  /// Check if this is a non-trivial type that would cause a C struct
1191  /// transitively containing this type to be non-trivial to copy and return the
1192  /// kind.
1194 
1195  /// Check if this is a non-trivial type that would cause a C struct
1196  /// transitively containing this type to be non-trivial to destructively
1197  /// move and return the kind. Destructive move in this context is a C++-style
1198  /// move in which the source object is placed in a valid but unspecified state
1199  /// after it is moved, as opposed to a truly destructive move in which the
1200  /// source object is placed in an uninitialized state.
1202 
1209  };
1210 
1211  /// Returns a nonzero value if objects of this type require
1212  /// non-trivial work to clean up after. Non-zero because it's
1213  /// conceivable that qualifiers (objc_gc(weak)?) could make
1214  /// something require destruction.
1216  return isDestructedTypeImpl(*this);
1217  }
1218 
1219  /// Check if this is or contains a C union that is non-trivial to
1220  /// default-initialize, which is a union that has a member that is non-trivial
1221  /// to default-initialize. If this returns true,
1222  /// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
1224 
1225  /// Check if this is or contains a C union that is non-trivial to destruct,
1226  /// which is a union that has a member that is non-trivial to destruct. If
1227  /// this returns true, isDestructedType returns DK_nontrivial_c_struct.
1229 
1230  /// Check if this is or contains a C union that is non-trivial to copy, which
1231  /// is a union that has a member that is non-trivial to copy. If this returns
1232  /// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
1234 
1235  /// Determine whether expressions of the given type are forbidden
1236  /// from being lvalues in C.
1237  ///
1238  /// The expression types that are forbidden to be lvalues are:
1239  /// - 'void', but not qualified void
1240  /// - function types
1241  ///
1242  /// The exact rule here is C99 6.3.2.1:
1243  /// An lvalue is an expression with an object type or an incomplete
1244  /// type other than void.
1245  bool isCForbiddenLValueType() const;
1246 
1247  /// Substitute type arguments for the Objective-C type parameters used in the
1248  /// subject type.
1249  ///
1250  /// \param ctx ASTContext in which the type exists.
1251  ///
1252  /// \param typeArgs The type arguments that will be substituted for the
1253  /// Objective-C type parameters in the subject type, which are generally
1254  /// computed via \c Type::getObjCSubstitutions. If empty, the type
1255  /// parameters will be replaced with their bounds or id/Class, as appropriate
1256  /// for the context.
1257  ///
1258  /// \param context The context in which the subject type was written.
1259  ///
1260  /// \returns the resulting type.
1262  ArrayRef<QualType> typeArgs,
1263  ObjCSubstitutionContext context) const;
1264 
1265  /// Substitute type arguments from an object type for the Objective-C type
1266  /// parameters used in the subject type.
1267  ///
1268  /// This operation combines the computation of type arguments for
1269  /// substitution (\c Type::getObjCSubstitutions) with the actual process of
1270  /// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1271  /// callers that need to perform a single substitution in isolation.
1272  ///
1273  /// \param objectType The type of the object whose member type we're
1274  /// substituting into. For example, this might be the receiver of a message
1275  /// or the base of a property access.
1276  ///
1277  /// \param dc The declaration context from which the subject type was
1278  /// retrieved, which indicates (for example) which type parameters should
1279  /// be substituted.
1280  ///
1281  /// \param context The context in which the subject type was written.
1282  ///
1283  /// \returns the subject type after replacing all of the Objective-C type
1284  /// parameters with their corresponding arguments.
1286  const DeclContext *dc,
1287  ObjCSubstitutionContext context) const;
1288 
1289  /// Strip Objective-C "__kindof" types from the given type.
1290  QualType stripObjCKindOfType(const ASTContext &ctx) const;
1291 
1292  /// Remove all qualifiers including _Atomic.
1294 
1295 private:
1296  // These methods are implemented in a separate translation unit;
1297  // "static"-ize them to avoid creating temporary QualTypes in the
1298  // caller.
1299  static bool isConstant(QualType T, const ASTContext& Ctx);
1300  static QualType getDesugaredType(QualType T, const ASTContext &Context);
1302  static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1303  static QualType getSingleStepDesugaredTypeImpl(QualType type,
1304  const ASTContext &C);
1305  static QualType IgnoreParens(QualType T);
1306  static DestructionKind isDestructedTypeImpl(QualType type);
1307 
1308  /// Check if \param RD is or contains a non-trivial C union.
1310  static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
1311  static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1312 };
1313 
1314 } // namespace clang
1315 
1316 namespace llvm {
1317 
1318 /// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1319 /// to a specific Type class.
1320 template<> struct simplify_type< ::clang::QualType> {
1322 
1324  return Val.getTypePtr();
1325  }
1326 };
1327 
1328 // Teach SmallPtrSet that QualType is "basically a pointer".
1329 template<>
1330 struct PointerLikeTypeTraits<clang::QualType> {
1331  static inline void *getAsVoidPointer(clang::QualType P) {
1332  return P.getAsOpaquePtr();
1333  }
1334 
1335  static inline clang::QualType getFromVoidPointer(void *P) {
1337  }
1338 
1339  // Various qualifiers go in low bits.
1340  static constexpr int NumLowBitsAvailable = 0;
1341 };
1342 
1343 } // namespace llvm
1344 
1345 namespace clang {
1346 
1347 /// Base class that is common to both the \c ExtQuals and \c Type
1348 /// classes, which allows \c QualType to access the common fields between the
1349 /// two.
1351  friend class ExtQuals;
1352  friend class QualType;
1353  friend class Type;
1354 
1355  /// The "base" type of an extended qualifiers type (\c ExtQuals) or
1356  /// a self-referential pointer (for \c Type).
1357  ///
1358  /// This pointer allows an efficient mapping from a QualType to its
1359  /// underlying type pointer.
1360  const Type *const BaseType;
1361 
1362  /// The canonical type of this type. A QualType.
1363  QualType CanonicalType;
1364 
1365  ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1366  : BaseType(baseType), CanonicalType(canon) {}
1367 };
1368 
1369 /// We can encode up to four bits in the low bits of a
1370 /// type pointer, but there are many more type qualifiers that we want
1371 /// to be able to apply to an arbitrary type. Therefore we have this
1372 /// struct, intended to be heap-allocated and used by QualType to
1373 /// store qualifiers.
1374 ///
1375 /// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1376 /// in three low bits on the QualType pointer; a fourth bit records whether
1377 /// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1378 /// Objective-C GC attributes) are much more rare.
1379 class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
1380  // NOTE: changing the fast qualifiers should be straightforward as
1381  // long as you don't make 'const' non-fast.
1382  // 1. Qualifiers:
1383  // a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1384  // Fast qualifiers must occupy the low-order bits.
1385  // b) Update Qualifiers::FastWidth and FastMask.
1386  // 2. QualType:
1387  // a) Update is{Volatile,Restrict}Qualified(), defined inline.
1388  // b) Update remove{Volatile,Restrict}, defined near the end of
1389  // this header.
1390  // 3. ASTContext:
1391  // a) Update get{Volatile,Restrict}Type.
1392 
1393  /// The immutable set of qualifiers applied by this node. Always contains
1394  /// extended qualifiers.
1395  Qualifiers Quals;
1396 
1397  ExtQuals *this_() { return this; }
1398 
1399 public:
1400  ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1401  : ExtQualsTypeCommonBase(baseType,
1402  canon.isNull() ? QualType(this_(), 0) : canon),
1403  Quals(quals) {
1404  assert(Quals.hasNonFastQualifiers()
1405  && "ExtQuals created with no fast qualifiers");
1406  assert(!Quals.hasFastQualifiers()
1407  && "ExtQuals created with fast qualifiers");
1408  }
1409 
1410  Qualifiers getQualifiers() const { return Quals; }
1411 
1412  bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1413  Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1414 
1415  bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1417  return Quals.getObjCLifetime();
1418  }
1419 
1420  bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1421  LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1422 
1423  const Type *getBaseType() const { return BaseType; }
1424 
1425 public:
1426  void Profile(llvm::FoldingSetNodeID &ID) const {
1427  Profile(ID, getBaseType(), Quals);
1428  }
1429 
1430  static void Profile(llvm::FoldingSetNodeID &ID,
1431  const Type *BaseType,
1432  Qualifiers Quals) {
1433  assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!");
1434  ID.AddPointer(BaseType);
1435  Quals.Profile(ID);
1436  }
1437 };
1438 
1439 /// The kind of C++11 ref-qualifier associated with a function type.
1440 /// This determines whether a member function's "this" object can be an
1441 /// lvalue, rvalue, or neither.
1443  /// No ref-qualifier was provided.
1444  RQ_None = 0,
1445 
1446  /// An lvalue ref-qualifier was provided (\c &).
1448 
1449  /// An rvalue ref-qualifier was provided (\c &&).
1451 };
1452 
1453 /// Which keyword(s) were used to create an AutoType.
1454 enum class AutoTypeKeyword {
1455  /// auto
1456  Auto,
1457 
1458  /// decltype(auto)
1459  DecltypeAuto,
1460 
1461  /// __auto_type (GNU extension)
1462  GNUAutoType
1463 };
1464 
1465 /// The base class of the type hierarchy.
1466 ///
1467 /// A central concept with types is that each type always has a canonical
1468 /// type. A canonical type is the type with any typedef names stripped out
1469 /// of it or the types it references. For example, consider:
1470 ///
1471 /// typedef int foo;
1472 /// typedef foo* bar;
1473 /// 'int *' 'foo *' 'bar'
1474 ///
1475 /// There will be a Type object created for 'int'. Since int is canonical, its
1476 /// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1477 /// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1478 /// there is a PointerType that represents 'int*', which, like 'int', is
1479 /// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1480 /// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1481 /// is also 'int*'.
1482 ///
1483 /// Non-canonical types are useful for emitting diagnostics, without losing
1484 /// information about typedefs being used. Canonical types are useful for type
1485 /// comparisons (they allow by-pointer equality tests) and useful for reasoning
1486 /// about whether something has a particular form (e.g. is a function type),
1487 /// because they implicitly, recursively, strip all typedefs out of a type.
1488 ///
1489 /// Types, once created, are immutable.
1490 ///
1491 class alignas(8) Type : public ExtQualsTypeCommonBase {
1492 public:
1493  enum TypeClass {
1494 #define TYPE(Class, Base) Class,
1495 #define LAST_TYPE(Class) TypeLast = Class
1496 #define ABSTRACT_TYPE(Class, Base)
1497 #include "clang/AST/TypeNodes.inc"
1498  };
1499 
1500 private:
1501  /// Bitfields required by the Type class.
1502  class TypeBitfields {
1503  friend class Type;
1504  template <class T> friend class TypePropertyCache;
1505 
1506  /// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1507  unsigned TC : 8;
1508 
1509  /// Store information on the type dependency.
1510  unsigned Dependence : llvm::BitWidth<TypeDependence>;
1511 
1512  /// True if the cache (i.e. the bitfields here starting with
1513  /// 'Cache') is valid.
1514  mutable unsigned CacheValid : 1;
1515 
1516  /// Linkage of this type.
1517  mutable unsigned CachedLinkage : 3;
1518 
1519  /// Whether this type involves and local or unnamed types.
1520  mutable unsigned CachedLocalOrUnnamed : 1;
1521 
1522  /// Whether this type comes from an AST file.
1523  mutable unsigned FromAST : 1;
1524 
1525  bool isCacheValid() const {
1526  return CacheValid;
1527  }
1528 
1529  Linkage getLinkage() const {
1530  assert(isCacheValid() && "getting linkage from invalid cache");
1531  return static_cast<Linkage>(CachedLinkage);
1532  }
1533 
1534  bool hasLocalOrUnnamedType() const {
1535  assert(isCacheValid() && "getting linkage from invalid cache");
1536  return CachedLocalOrUnnamed;
1537  }
1538  };
1539  enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };
1540 
1541 protected:
1542  // These classes allow subclasses to somewhat cleanly pack bitfields
1543  // into Type.
1544 
1546  friend class ArrayType;
1547 
1548  unsigned : NumTypeBits;
1549 
1550  /// CVR qualifiers from declarations like
1551  /// 'int X[static restrict 4]'. For function parameters only.
1552  unsigned IndexTypeQuals : 3;
1553 
1554  /// Storage class qualifiers from declarations like
1555  /// 'int X[static restrict 4]'. For function parameters only.
1556  /// Actually an ArrayType::ArraySizeModifier.
1557  unsigned SizeModifier : 3;
1558  };
1559 
1561  friend class ConstantArrayType;
1562 
1563  unsigned : NumTypeBits + 3 + 3;
1564 
1565  /// Whether we have a stored size expression.
1566  unsigned HasStoredSizeExpr : 1;
1567  };
1568 
1570  friend class BuiltinType;
1571 
1572  unsigned : NumTypeBits;
1573 
1574  /// The kind (BuiltinType::Kind) of builtin type this is.
1575  unsigned Kind : 8;
1576  };
1577 
1578  /// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
1579  /// Only common bits are stored here. Additional uncommon bits are stored
1580  /// in a trailing object after FunctionProtoType.
1582  friend class FunctionProtoType;
1583  friend class FunctionType;
1584 
1585  unsigned : NumTypeBits;
1586 
1587  /// Extra information which affects how the function is called, like
1588  /// regparm and the calling convention.
1589  unsigned ExtInfo : 13;
1590 
1591  /// The ref-qualifier associated with a \c FunctionProtoType.
1592  ///
1593  /// This is a value of type \c RefQualifierKind.
1594  unsigned RefQualifier : 2;
1595 
1596  /// Used only by FunctionProtoType, put here to pack with the
1597  /// other bitfields.
1598  /// The qualifiers are part of FunctionProtoType because...
1599  ///
1600  /// C++ 8.3.5p4: The return type, the parameter type list and the
1601  /// cv-qualifier-seq, [...], are part of the function type.
1602  unsigned FastTypeQuals : Qualifiers::FastWidth;
1603  /// Whether this function has extended Qualifiers.
1604  unsigned HasExtQuals : 1;
1605 
1606  /// The number of parameters this function has, not counting '...'.
1607  /// According to [implimits] 8 bits should be enough here but this is
1608  /// somewhat easy to exceed with metaprogramming and so we would like to
1609  /// keep NumParams as wide as reasonably possible.
1610  unsigned NumParams : 16;
1611 
1612  /// The type of exception specification this function has.
1613  unsigned ExceptionSpecType : 4;
1614 
1615  /// Whether this function has extended parameter information.
1616  unsigned HasExtParameterInfos : 1;
1617 
1618  /// Whether the function is variadic.
1619  unsigned Variadic : 1;
1620 
1621  /// Whether this function has a trailing return type.
1622  unsigned HasTrailingReturn : 1;
1623  };
1624 
1626  friend class ObjCObjectType;
1627 
1628  unsigned : NumTypeBits;
1629 
1630  /// The number of type arguments stored directly on this object type.
1631  unsigned NumTypeArgs : 7;
1632 
1633  /// The number of protocols stored directly on this object type.
1634  unsigned NumProtocols : 6;
1635 
1636  /// Whether this is a "kindof" type.
1637  unsigned IsKindOf : 1;
1638  };
1639 
1641  friend class ReferenceType;
1642 
1643  unsigned : NumTypeBits;
1644 
1645  /// True if the type was originally spelled with an lvalue sigil.
1646  /// This is never true of rvalue references but can also be false
1647  /// on lvalue references because of C++0x [dcl.typedef]p9,
1648  /// as follows:
1649  ///
1650  /// typedef int &ref; // lvalue, spelled lvalue
1651  /// typedef int &&rvref; // rvalue
1652  /// ref &a; // lvalue, inner ref, spelled lvalue
1653  /// ref &&a; // lvalue, inner ref
1654  /// rvref &a; // lvalue, inner ref, spelled lvalue
1655  /// rvref &&a; // rvalue, inner ref
1656  unsigned SpelledAsLValue : 1;
1657 
1658  /// True if the inner type is a reference type. This only happens
1659  /// in non-canonical forms.
1660  unsigned InnerRef : 1;
1661  };
1662 
1664  friend class TypeWithKeyword;
1665 
1666  unsigned : NumTypeBits;
1667 
1668  /// An ElaboratedTypeKeyword. 8 bits for efficient access.
1669  unsigned Keyword : 8;
1670  };
1671 
1673 
1675  friend class ElaboratedType;
1676 
1677  unsigned : NumTypeBits;
1679 
1680  /// Whether the ElaboratedType has a trailing OwnedTagDecl.
1681  unsigned HasOwnedTagDecl : 1;
1682  };
1683 
1685  friend class VectorType;
1686  friend class DependentVectorType;
1687 
1688  unsigned : NumTypeBits;
1689 
1690  /// The kind of vector, either a generic vector type or some
1691  /// target-specific vector type such as for AltiVec or Neon.
1692  unsigned VecKind : 3;
1693  /// The number of elements in the vector.
1694  uint32_t NumElements;
1695  };
1696 
1698  friend class AttributedType;
1699 
1700  unsigned : NumTypeBits;
1701 
1702  /// An AttributedType::Kind
1703  unsigned AttrKind : 32 - NumTypeBits;
1704  };
1705 
1707  friend class AutoType;
1708 
1709  unsigned : NumTypeBits;
1710 
1711  /// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1712  /// or '__auto_type'? AutoTypeKeyword value.
1713  unsigned Keyword : 2;
1714 
1715  /// The number of template arguments in the type-constraints, which is
1716  /// expected to be able to hold at least 1024 according to [implimits].
1717  /// However as this limit is somewhat easy to hit with template
1718  /// metaprogramming we'd prefer to keep it as large as possible.
1719  /// At the moment it has been left as a non-bitfield since this type
1720  /// safely fits in 64 bits as an unsigned, so there is no reason to
1721  /// introduce the performance impact of a bitfield.
1722  unsigned NumArgs;
1723  };
1724 
1727 
1728  unsigned : NumTypeBits;
1729 
1730  /// The number of template arguments in \c Arguments, which is
1731  /// expected to be able to hold at least 1024 according to [implimits].
1732  /// However as this limit is somewhat easy to hit with template
1733  /// metaprogramming we'd prefer to keep it as large as possible.
1734  /// At the moment it has been left as a non-bitfield since this type
1735  /// safely fits in 64 bits as an unsigned, so there is no reason to
1736  /// introduce the performance impact of a bitfield.
1737  unsigned NumArgs;
1738  };
1739 
1742 
1743  unsigned : NumTypeBits;
1744 
1745  /// Whether this template specialization type is a substituted type alias.
1746  unsigned TypeAlias : 1;
1747 
1748  /// The number of template arguments named in this class template
1749  /// specialization, which is expected to be able to hold at least 1024
1750  /// according to [implimits]. However, as this limit is somewhat easy to
1751  /// hit with template metaprogramming we'd prefer to keep it as large
1752  /// as possible. At the moment it has been left as a non-bitfield since
1753  /// this type safely fits in 64 bits as an unsigned, so there is no reason
1754  /// to introduce the performance impact of a bitfield.
1755  unsigned NumArgs;
1756  };
1757 
1760 
1761  unsigned : NumTypeBits;
1763 
1764  /// The number of template arguments named in this class template
1765  /// specialization, which is expected to be able to hold at least 1024
1766  /// according to [implimits]. However, as this limit is somewhat easy to
1767  /// hit with template metaprogramming we'd prefer to keep it as large
1768  /// as possible. At the moment it has been left as a non-bitfield since
1769  /// this type safely fits in 64 bits as an unsigned, so there is no reason
1770  /// to introduce the performance impact of a bitfield.
1771  unsigned NumArgs;
1772  };
1773 
1775  friend class PackExpansionType;
1776 
1777  unsigned : NumTypeBits;
1778 
1779  /// The number of expansions that this pack expansion will
1780  /// generate when substituted (+1), which is expected to be able to
1781  /// hold at least 1024 according to [implimits]. However, as this limit
1782  /// is somewhat easy to hit with template metaprogramming we'd prefer to
1783  /// keep it as large as possible. At the moment it has been left as a
1784  /// non-bitfield since this type safely fits in 64 bits as an unsigned, so
1785  /// there is no reason to introduce the performance impact of a bitfield.
1786  ///
1787  /// This field will only have a non-zero value when some of the parameter
1788  /// packs that occur within the pattern have been substituted but others
1789  /// have not.
1790  unsigned NumExpansions;
1791  };
1792 
1793  union {
1794  TypeBitfields TypeBits;
1811  };
1812 
1813 private:
1814  template <class T> friend class TypePropertyCache;
1815 
1816  /// Set whether this type comes from an AST file.
1817  void setFromAST(bool V = true) const {
1818  TypeBits.FromAST = V;
1819  }
1820 
1821 protected:
1822  friend class ASTContext;
1823 
1825  : ExtQualsTypeCommonBase(this,
1826  canon.isNull() ? QualType(this_(), 0) : canon) {
1827  static_assert(sizeof(*this) <= 8 + sizeof(ExtQualsTypeCommonBase),
1828  "changing bitfields changed sizeof(Type)!");
1829  static_assert(alignof(decltype(*this)) % sizeof(void *) == 0,
1830  "Insufficient alignment!");
1831  TypeBits.TC = tc;
1832  TypeBits.Dependence = static_cast<unsigned>(Dependence);
1833  TypeBits.CacheValid = false;
1834  TypeBits.CachedLocalOrUnnamed = false;
1835  TypeBits.CachedLinkage = NoLinkage;
1836  TypeBits.FromAST = false;
1837  }
1838 
1839  // silence VC++ warning C4355: 'this' : used in base member initializer list
1840  Type *this_() { return this; }
1841 
1843  TypeBits.Dependence = static_cast<unsigned>(D);
1844  }
1845 
1847 
1848 public:
1849  friend class ASTReader;
1850  friend class ASTWriter;
1851  template <class T> friend class serialization::AbstractTypeReader;
1852  template <class T> friend class serialization::AbstractTypeWriter;
1853 
1854  Type(const Type &) = delete;
1855  Type(Type &&) = delete;
1856  Type &operator=(const Type &) = delete;
1857  Type &operator=(Type &&) = delete;
1858 
1859  TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
1860 
1861  /// Whether this type comes from an AST file.
1862  bool isFromAST() const { return TypeBits.FromAST; }
1863 
1864  /// Whether this type is or contains an unexpanded parameter
1865  /// pack, used to support C++0x variadic templates.
1866  ///
1867  /// A type that contains a parameter pack shall be expanded by the
1868  /// ellipsis operator at some point. For example, the typedef in the
1869  /// following example contains an unexpanded parameter pack 'T':
1870  ///
1871  /// \code
1872  /// template<typename ...T>
1873  /// struct X {
1874  /// typedef T* pointer_types; // ill-formed; T is a parameter pack.
1875  /// };
1876  /// \endcode
1877  ///
1878  /// Note that this routine does not specify which
1880  return getDependence() & TypeDependence::UnexpandedPack;
1881  }
1882 
1883  /// Determines if this type would be canonical if it had no further
1884  /// qualification.
1885  bool isCanonicalUnqualified() const {
1886  return CanonicalType == QualType(this, 0);
1887  }
1888 
1889  /// Pull a single level of sugar off of this locally-unqualified type.
1890  /// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
1891  /// or QualType::getSingleStepDesugaredType(const ASTContext&).
1893 
1894  /// As an extension, we classify types as one of "sized" or "sizeless";
1895  /// every type is one or the other. Standard types are all sized;
1896  /// sizeless types are purely an extension.
1897  ///
1898  /// Sizeless types contain data with no specified size, alignment,
1899  /// or layout.
1900  bool isSizelessType() const;
1901  bool isSizelessBuiltinType() const;
1902 
1903  /// Determines if this is a sizeless type supported by the
1904  /// 'arm_sve_vector_bits' type attribute, which can be applied to a single
1905  /// SVE vector or predicate, excluding tuple types such as svint32x4_t.
1906  bool isVLSTBuiltinType() const;
1907 
1908  /// Returns the representative type for the element of an SVE builtin type.
1909  /// This is used to represent fixed-length SVE vectors created with the
1910  /// 'arm_sve_vector_bits' type attribute as VectorType.
1911  QualType getSveEltType(const ASTContext &Ctx) const;
1912 
1913  /// Types are partitioned into 3 broad categories (C99 6.2.5p1):
1914  /// object types, function types, and incomplete types.
1915 
1916  /// Return true if this is an incomplete type.
1917  /// A type that can describe objects, but which lacks information needed to
1918  /// determine its size (e.g. void, or a fwd declared struct). Clients of this
1919  /// routine will need to determine if the size is actually required.
1920  ///
1921  /// Def If non-null, and the type refers to some kind of declaration
1922  /// that can be completed (such as a C struct, C++ class, or Objective-C
1923  /// class), will be set to the declaration.
1924  bool isIncompleteType(NamedDecl **Def = nullptr) const;
1925 
1926  /// Return true if this is an incomplete or object
1927  /// type, in other words, not a function type.
1929  return !isFunctionType();
1930  }
1931 
1932  /// Determine whether this type is an object type.
1933  bool isObjectType() const {
1934  // C++ [basic.types]p8:
1935  // An object type is a (possibly cv-qualified) type that is not a
1936  // function type, not a reference type, and not a void type.
1937  return !isReferenceType() && !isFunctionType() && !isVoidType();
1938  }
1939 
1940  /// Return true if this is a literal type
1941  /// (C++11 [basic.types]p10)
1942  bool isLiteralType(const ASTContext &Ctx) const;
1943 
1944  /// Determine if this type is a structural type, per C++20 [temp.param]p7.
1945  bool isStructuralType() const;
1946 
1947  /// Test if this type is a standard-layout type.
1948  /// (C++0x [basic.type]p9)
1949  bool isStandardLayoutType() const;
1950 
1951  /// Helper methods to distinguish type categories. All type predicates
1952  /// operate on the canonical type, ignoring typedefs and qualifiers.
1953 
1954  /// Returns true if the type is a builtin type.
1955  bool isBuiltinType() const;
1956 
1957  /// Test for a particular builtin type.
1958  bool isSpecificBuiltinType(unsigned K) const;
1959 
1960  /// Test for a type which does not represent an actual type-system type but
1961  /// is instead used as a placeholder for various convenient purposes within
1962  /// Clang. All such types are BuiltinTypes.
1963  bool isPlaceholderType() const;
1964  const BuiltinType *getAsPlaceholderType() const;
1965 
1966  /// Test for a specific placeholder type.
1967  bool isSpecificPlaceholderType(unsigned K) const;
1968 
1969  /// Test for a placeholder type other than Overload; see
1970  /// BuiltinType::isNonOverloadPlaceholderType.
1971  bool isNonOverloadPlaceholderType() const;
1972 
1973  /// isIntegerType() does *not* include complex integers (a GCC extension).
1974  /// isComplexIntegerType() can be used to test for complex integers.
1975  bool isIntegerType() const; // C99 6.2.5p17 (int, char, bool, enum)
1976  bool isEnumeralType() const;
1977 
1978  /// Determine whether this type is a scoped enumeration type.
1979  bool isScopedEnumeralType() const;
1980  bool isBooleanType() const;
1981  bool isCharType() const;
1982  bool isWideCharType() const;
1983  bool isChar8Type() const;
1984  bool isChar16Type() const;
1985  bool isChar32Type() const;
1986  bool isAnyCharacterType() const;
1987  bool isIntegralType(const ASTContext &Ctx) const;
1988 
1989  /// Determine whether this type is an integral or enumeration type.
1990  bool isIntegralOrEnumerationType() const;
1991 
1992  /// Determine whether this type is an integral or unscoped enumeration type.
1994  bool isUnscopedEnumerationType() const;
1995 
1996  /// Floating point categories.
1997  bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
1998  /// isComplexType() does *not* include complex integers (a GCC extension).
1999  /// isComplexIntegerType() can be used to test for complex integers.
2000  bool isComplexType() const; // C99 6.2.5p11 (complex)
2001  bool isAnyComplexType() const; // C99 6.2.5p11 (complex) + Complex Int.
2002  bool isFloatingType() const; // C99 6.2.5p11 (real floating + complex)
2003  bool isHalfType() const; // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
2004  bool isFloat16Type() const; // C11 extension ISO/IEC TS 18661
2005  bool isBFloat16Type() const;
2006  bool isFloat128Type() const;
2007  bool isIbm128Type() const;
2008  bool isRealType() const; // C99 6.2.5p17 (real floating + integer)
2009  bool isArithmeticType() const; // C99 6.2.5p18 (integer + floating)
2010  bool isVoidType() const; // C99 6.2.5p19
2011  bool isScalarType() const; // C99 6.2.5p21 (arithmetic + pointers)
2012  bool isAggregateType() const;
2013  bool isFundamentalType() const;
2014  bool isCompoundType() const;
2015 
2016  // Type Predicates: Check to see if this type is structurally the specified
2017  // type, ignoring typedefs and qualifiers.
2018  bool isFunctionType() const;
2019  bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
2020  bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
2021  bool isPointerType() const;
2022  bool isAnyPointerType() const; // Any C pointer or ObjC object pointer
2023  bool isBlockPointerType() const;
2024  bool isVoidPointerType() const;
2025  bool isReferenceType() const;
2026  bool isLValueReferenceType() const;
2027  bool isRValueReferenceType() const;
2028  bool isObjectPointerType() const;
2029  bool isFunctionPointerType() const;
2030  bool isFunctionReferenceType() const;
2031  bool isMemberPointerType() const;
2032  bool isMemberFunctionPointerType() const;
2033  bool isMemberDataPointerType() const;
2034  bool isArrayType() const;
2035  bool isConstantArrayType() const;
2036  bool isIncompleteArrayType() const;
2037  bool isVariableArrayType() const;
2038  bool isDependentSizedArrayType() const;
2039  bool isRecordType() const;
2040  bool isClassType() const;
2041  bool isStructureType() const;
2042  bool isObjCBoxableRecordType() const;
2043  bool isInterfaceType() const;
2044  bool isStructureOrClassType() const;
2045  bool isUnionType() const;
2046  bool isComplexIntegerType() const; // GCC _Complex integer type.
2047  bool isVectorType() const; // GCC vector type.
2048  bool isExtVectorType() const; // Extended vector type.
2049  bool isMatrixType() const; // Matrix type.
2050  bool isConstantMatrixType() const; // Constant matrix type.
2051  bool isDependentAddressSpaceType() const; // value-dependent address space qualifier
2052  bool isObjCObjectPointerType() const; // pointer to ObjC object
2053  bool isObjCRetainableType() const; // ObjC object or block pointer
2054  bool isObjCLifetimeType() const; // (array of)* retainable type
2055  bool isObjCIndirectLifetimeType() const; // (pointer to)* lifetime type
2056  bool isObjCNSObjectType() const; // __attribute__((NSObject))
2057  bool isObjCIndependentClassType() const; // __attribute__((objc_independent_class))
2058  // FIXME: change this to 'raw' interface type, so we can used 'interface' type
2059  // for the common case.
2060  bool isObjCObjectType() const; // NSString or typeof(*(id)0)
2061  bool isObjCQualifiedInterfaceType() const; // NSString<foo>
2062  bool isObjCQualifiedIdType() const; // id<foo>
2063  bool isObjCQualifiedClassType() const; // Class<foo>
2064  bool isObjCObjectOrInterfaceType() const;
2065  bool isObjCIdType() const; // id
2066  bool isDecltypeType() const;
2067  /// Was this type written with the special inert-in-ARC __unsafe_unretained
2068  /// qualifier?
2069  ///
2070  /// This approximates the answer to the following question: if this
2071  /// translation unit were compiled in ARC, would this type be qualified
2072  /// with __unsafe_unretained?
2074  return hasAttr(attr::ObjCInertUnsafeUnretained);
2075  }
2076 
2077  /// Whether the type is Objective-C 'id' or a __kindof type of an
2078  /// object type, e.g., __kindof NSView * or __kindof id
2079  /// <NSCopying>.
2080  ///
2081  /// \param bound Will be set to the bound on non-id subtype types,
2082  /// which will be (possibly specialized) Objective-C class type, or
2083  /// null for 'id.
2084  bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
2085  const ObjCObjectType *&bound) const;
2086 
2087  bool isObjCClassType() const; // Class
2088 
2089  /// Whether the type is Objective-C 'Class' or a __kindof type of an
2090  /// Class type, e.g., __kindof Class <NSCopying>.
2091  ///
2092  /// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
2093  /// here because Objective-C's type system cannot express "a class
2094  /// object for a subclass of NSFoo".
2095  bool isObjCClassOrClassKindOfType() const;
2096 
2098  bool isObjCSelType() const; // Class
2099  bool isObjCBuiltinType() const; // 'id' or 'Class'
2100  bool isObjCARCBridgableType() const;
2101  bool isCARCBridgableType() const;
2102  bool isTemplateTypeParmType() const; // C++ template type parameter
2103  bool isNullPtrType() const; // C++11 std::nullptr_t
2104  bool isNothrowT() const; // C++ std::nothrow_t
2105  bool isAlignValT() const; // C++17 std::align_val_t
2106  bool isStdByteType() const; // C++17 std::byte
2107  bool isAtomicType() const; // C11 _Atomic()
2108  bool isUndeducedAutoType() const; // C++11 auto or
2109  // C++14 decltype(auto)
2110  bool isTypedefNameType() const; // typedef or alias template
2111 
2112 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
2113  bool is##Id##Type() const;
2114 #include "clang/Basic/OpenCLImageTypes.def"
2115 
2116  bool isImageType() const; // Any OpenCL image type
2117 
2118  bool isSamplerT() const; // OpenCL sampler_t
2119  bool isEventT() const; // OpenCL event_t
2120  bool isClkEventT() const; // OpenCL clk_event_t
2121  bool isQueueT() const; // OpenCL queue_t
2122  bool isReserveIDT() const; // OpenCL reserve_id_t
2123 
2124 #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
2125  bool is##Id##Type() const;
2126 #include "clang/Basic/OpenCLExtensionTypes.def"
2127  // Type defined in cl_intel_device_side_avc_motion_estimation OpenCL extension
2128  bool isOCLIntelSubgroupAVCType() const;
2129  bool isOCLExtOpaqueType() const; // Any OpenCL extension type
2130 
2131  bool isPipeType() const; // OpenCL pipe type
2132  bool isBitIntType() const; // Bit-precise integer type
2133  bool isOpenCLSpecificType() const; // Any OpenCL specific type
2134 
2135  /// Determines if this type, which must satisfy
2136  /// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
2137  /// than implicitly __strong.
2138  bool isObjCARCImplicitlyUnretainedType() const;
2139 
2140  /// Check if the type is the CUDA device builtin surface type.
2141  bool isCUDADeviceBuiltinSurfaceType() const;
2142  /// Check if the type is the CUDA device builtin texture type.
2143  bool isCUDADeviceBuiltinTextureType() const;
2144 
2145  /// Return the implicit lifetime for this type, which must not be dependent.
2147 
2159  };
2160 
2161  /// Given that this is a scalar type, classify it.
2163 
2165  return static_cast<TypeDependence>(TypeBits.Dependence);
2166  }
2167 
2168  /// Whether this type is an error type.
2169  bool containsErrors() const {
2171  }
2172 
2173  /// Whether this type is a dependent type, meaning that its definition
2174  /// somehow depends on a template parameter (C++ [temp.dep.type]).
2175  bool isDependentType() const {
2176  return getDependence() & TypeDependence::Dependent;
2177  }
2178 
2179  /// Determine whether this type is an instantiation-dependent type,
2180  /// meaning that the type involves a template parameter (even if the
2181  /// definition does not actually depend on the type substituted for that
2182  /// template parameter).
2184  return getDependence() & TypeDependence::Instantiation;
2185  }
2186 
2187  /// Determine whether this type is an undeduced type, meaning that
2188  /// it somehow involves a C++11 'auto' type or similar which has not yet been
2189  /// deduced.
2190  bool isUndeducedType() const;
2191 
2192  /// Whether this type is a variably-modified type (C99 6.7.5).
2193  bool isVariablyModifiedType() const {
2194  return getDependence() & TypeDependence::VariablyModified;
2195  }
2196 
2197  /// Whether this type involves a variable-length array type
2198  /// with a definite size.
2199  bool hasSizedVLAType() const;
2200 
2201  /// Whether this type is or contains a local or unnamed type.
2202  bool hasUnnamedOrLocalType() const;
2203 
2204  bool isOverloadableType() const;
2205 
2206  /// Determine wither this type is a C++ elaborated-type-specifier.
2207  bool isElaboratedTypeSpecifier() const;
2208 
2209  bool canDecayToPointerType() const;
2210 
2211  /// Whether this type is represented natively as a pointer. This includes
2212  /// pointers, references, block pointers, and Objective-C interface,
2213  /// qualified id, and qualified interface types, as well as nullptr_t.
2214  bool hasPointerRepresentation() const;
2215 
2216  /// Whether this type can represent an objective pointer type for the
2217  /// purpose of GC'ability
2218  bool hasObjCPointerRepresentation() const;
2219 
2220  /// Determine whether this type has an integer representation
2221  /// of some sort, e.g., it is an integer type or a vector.
2222  bool hasIntegerRepresentation() const;
2223 
2224  /// Determine whether this type has an signed integer representation
2225  /// of some sort, e.g., it is an signed integer type or a vector.
2226  bool hasSignedIntegerRepresentation() const;
2227 
2228  /// Determine whether this type has an unsigned integer representation
2229  /// of some sort, e.g., it is an unsigned integer type or a vector.
2230  bool hasUnsignedIntegerRepresentation() const;
2231 
2232  /// Determine whether this type has a floating-point representation
2233  /// of some sort, e.g., it is a floating-point type or a vector thereof.
2234  bool hasFloatingRepresentation() const;
2235 
2236  // Type Checking Functions: Check to see if this type is structurally the
2237  // specified type, ignoring typedefs and qualifiers, and return a pointer to
2238  // the best type we can.
2239  const RecordType *getAsStructureType() const;
2240  /// NOTE: getAs*ArrayType are methods on ASTContext.
2241  const RecordType *getAsUnionType() const;
2242  const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
2243  const ObjCObjectType *getAsObjCInterfaceType() const;
2244 
2245  // The following is a convenience method that returns an ObjCObjectPointerType
2246  // for object declared using an interface.
2251 
2252  /// Retrieves the CXXRecordDecl that this type refers to, either
2253  /// because the type is a RecordType or because it is the injected-class-name
2254  /// type of a class template or class template partial specialization.
2256 
2257  /// Retrieves the RecordDecl this type refers to.
2258  RecordDecl *getAsRecordDecl() const;
2259 
2260  /// Retrieves the TagDecl that this type refers to, either
2261  /// because the type is a TagType or because it is the injected-class-name
2262  /// type of a class template or class template partial specialization.
2263  TagDecl *getAsTagDecl() const;
2264 
2265  /// If this is a pointer or reference to a RecordType, return the
2266  /// CXXRecordDecl that the type refers to.
2267  ///
2268  /// If this is not a pointer or reference, or the type being pointed to does
2269  /// not refer to a CXXRecordDecl, returns NULL.
2270  const CXXRecordDecl *getPointeeCXXRecordDecl() const;
2271 
2272  /// Get the DeducedType whose type will be deduced for a variable with
2273  /// an initializer of this type. This looks through declarators like pointer
2274  /// types, but not through decltype or typedefs.
2276 
2277  /// Get the AutoType whose type will be deduced for a variable with
2278  /// an initializer of this type. This looks through declarators like pointer
2279  /// types, but not through decltype or typedefs.
2281  return dyn_cast_or_null<AutoType>(getContainedDeducedType());
2282  }
2283 
2284  /// Determine whether this type was written with a leading 'auto'
2285  /// corresponding to a trailing return type (possibly for a nested
2286  /// function type within a pointer to function type or similar).
2287  bool hasAutoForTrailingReturnType() const;
2288 
2289  /// Member-template getAs<specific type>'. Look through sugar for
2290  /// an instance of <specific type>. This scheme will eventually
2291  /// replace the specific getAsXXXX methods above.
2292  ///
2293  /// There are some specializations of this member template listed
2294  /// immediately following this class.
2295  template <typename T> const T *getAs() const;
2296 
2297  /// Member-template getAsAdjusted<specific type>. Look through specific kinds
2298  /// of sugar (parens, attributes, etc) for an instance of <specific type>.
2299  /// This is used when you need to walk over sugar nodes that represent some
2300  /// kind of type adjustment from a type that was written as a <specific type>
2301  /// to another type that is still canonically a <specific type>.
2302  template <typename T> const T *getAsAdjusted() const;
2303 
2304  /// A variant of getAs<> for array types which silently discards
2305  /// qualifiers from the outermost type.
2306  const ArrayType *getAsArrayTypeUnsafe() const;
2307 
2308  /// Member-template castAs<specific type>. Look through sugar for
2309  /// the underlying instance of <specific type>.
2310  ///
2311  /// This method has the same relationship to getAs<T> as cast<T> has
2312  /// to dyn_cast<T>; which is to say, the underlying type *must*
2313  /// have the intended type, and this method will never return null.
2314  template <typename T> const T *castAs() const;
2315 
2316  /// A variant of castAs<> for array type which silently discards
2317  /// qualifiers from the outermost type.
2318  const ArrayType *castAsArrayTypeUnsafe() const;
2319 
2320  /// Determine whether this type had the specified attribute applied to it
2321  /// (looking through top-level type sugar).
2322  bool hasAttr(attr::Kind AK) const;
2323 
2324  /// Get the base element type of this type, potentially discarding type
2325  /// qualifiers. This should never be used when type qualifiers
2326  /// are meaningful.
2327  const Type *getBaseElementTypeUnsafe() const;
2328 
2329  /// If this is an array type, return the element type of the array,
2330  /// potentially with type qualifiers missing.
2331  /// This should never be used when type qualifiers are meaningful.
2332  const Type *getArrayElementTypeNoTypeQual() const;
2333 
2334  /// If this is a pointer type, return the pointee type.
2335  /// If this is an array type, return the array element type.
2336  /// This should never be used when type qualifiers are meaningful.
2337  const Type *getPointeeOrArrayElementType() const;
2338 
2339  /// If this is a pointer, ObjC object pointer, or block
2340  /// pointer, this returns the respective pointee.
2341  QualType getPointeeType() const;
2342 
2343  /// Return the specified type with any "sugar" removed from the type,
2344  /// removing any typedefs, typeofs, etc., as well as any qualifiers.
2345  const Type *getUnqualifiedDesugaredType() const;
2346 
2347  /// More type predicates useful for type checking/promotion
2348  bool isPromotableIntegerType() const; // C99 6.3.1.1p2
2349 
2350  /// Return true if this is an integer type that is
2351  /// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
2352  /// or an enum decl which has a signed representation.
2353  bool isSignedIntegerType() const;
2354 
2355  /// Return true if this is an integer type that is
2356  /// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
2357  /// or an enum decl which has an unsigned representation.
2358  bool isUnsignedIntegerType() const;
2359 
2360  /// Determines whether this is an integer type that is signed or an
2361  /// enumeration types whose underlying type is a signed integer type.
2362  bool isSignedIntegerOrEnumerationType() const;
2363 
2364  /// Determines whether this is an integer type that is unsigned or an
2365  /// enumeration types whose underlying type is a unsigned integer type.
2367 
2368  /// Return true if this is a fixed point type according to
2369  /// ISO/IEC JTC1 SC22 WG14 N1169.
2370  bool isFixedPointType() const;
2371 
2372  /// Return true if this is a fixed point or integer type.
2373  bool isFixedPointOrIntegerType() const;
2374 
2375  /// Return true if this is a saturated fixed point type according to
2376  /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2377  bool isSaturatedFixedPointType() const;
2378 
2379  /// Return true if this is a saturated fixed point type according to
2380  /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2381  bool isUnsaturatedFixedPointType() const;
2382 
2383  /// Return true if this is a fixed point type that is signed according
2384  /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2385  bool isSignedFixedPointType() const;
2386 
2387  /// Return true if this is a fixed point type that is unsigned according
2388  /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2389  bool isUnsignedFixedPointType() const;
2390 
2391  /// Return true if this is not a variable sized type,
2392  /// according to the rules of C99 6.7.5p3. It is not legal to call this on
2393  /// incomplete types.
2394  bool isConstantSizeType() const;
2395 
2396  /// Returns true if this type can be represented by some
2397  /// set of type specifiers.
2398  bool isSpecifierType() const;
2399 
2400  /// Determine the linkage of this type.
2401  Linkage getLinkage() const;
2402 
2403  /// Determine the visibility of this type.
2406  }
2407 
2408  /// Return true if the visibility was explicitly set is the code.
2409  bool isVisibilityExplicit() const {
2411  }
2412 
2413  /// Determine the linkage and visibility of this type.
2415 
2416  /// True if the computed linkage is valid. Used for consistency
2417  /// checking. Should always return true.
2418  bool isLinkageValid() const;
2419 
2420  /// Determine the nullability of the given type.
2421  ///
2422  /// Note that nullability is only captured as sugar within the type
2423  /// system, not as part of the canonical type, so nullability will
2424  /// be lost by canonicalization and desugaring.
2425  Optional<NullabilityKind> getNullability(const ASTContext &context) const;
2426 
2427  /// Determine whether the given type can have a nullability
2428  /// specifier applied to it, i.e., if it is any kind of pointer type.
2429  ///
2430  /// \param ResultIfUnknown The value to return if we don't yet know whether
2431  /// this type can have nullability because it is dependent.
2432  bool canHaveNullability(bool ResultIfUnknown = true) const;
2433 
2434  /// Retrieve the set of substitutions required when accessing a member
2435  /// of the Objective-C receiver type that is declared in the given context.
2436  ///
2437  /// \c *this is the type of the object we're operating on, e.g., the
2438  /// receiver for a message send or the base of a property access, and is
2439  /// expected to be of some object or object pointer type.
2440  ///
2441  /// \param dc The declaration context for which we are building up a
2442  /// substitution mapping, which should be an Objective-C class, extension,
2443  /// category, or method within.
2444  ///
2445  /// \returns an array of type arguments that can be substituted for
2446  /// the type parameters of the given declaration context in any type described
2447  /// within that context, or an empty optional to indicate that no
2448  /// substitution is required.
2450  getObjCSubstitutions(const DeclContext *dc) const;
2451 
2452  /// Determines if this is an ObjC interface type that may accept type
2453  /// parameters.
2454  bool acceptsObjCTypeParams() const;
2455 
2456  const char *getTypeClassName() const;
2457 
2459  return CanonicalType;
2460  }
2461 
2462  CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
2463  void dump() const;
2464  void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
2465 };
2466 
2467 /// This will check for a TypedefType by removing any existing sugar
2468 /// until it reaches a TypedefType or a non-sugared type.
2469 template <> const TypedefType *Type::getAs() const;
2470 
2471 /// This will check for a TemplateSpecializationType by removing any
2472 /// existing sugar until it reaches a TemplateSpecializationType or a
2473 /// non-sugared type.
2474 template <> const TemplateSpecializationType *Type::getAs() const;
2475 
2476 /// This will check for an AttributedType by removing any existing sugar
2477 /// until it reaches an AttributedType or a non-sugared type.
2478 template <> const AttributedType *Type::getAs() const;
2479 
2480 // We can do canonical leaf types faster, because we don't have to
2481 // worry about preserving child type decoration.
2482 #define TYPE(Class, Base)
2483 #define LEAF_TYPE(Class) \
2484 template <> inline const Class##Type *Type::getAs() const { \
2485  return dyn_cast<Class##Type>(CanonicalType); \
2486 } \
2487 template <> inline const Class##Type *Type::castAs() const { \
2488  return cast<Class##Type>(CanonicalType); \
2489 }
2490 #include "clang/AST/TypeNodes.inc"
2491 
2492 /// This class is used for builtin types like 'int'. Builtin
2493 /// types are always canonical and have a literal name field.
2494 class BuiltinType : public Type {
2495 public:
2496  enum Kind {
2497 // OpenCL image types
2498 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2499 #include "clang/Basic/OpenCLImageTypes.def"
2500 // OpenCL extension types
2501 #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) Id,
2502 #include "clang/Basic/OpenCLExtensionTypes.def"
2503 // SVE Types
2504 #define SVE_TYPE(Name, Id, SingletonId) Id,
2505 #include "clang/Basic/AArch64SVEACLETypes.def"
2506 // PPC MMA Types
2507 #define PPC_VECTOR_TYPE(Name, Id, Size) Id,
2508 #include "clang/Basic/PPCTypes.def"
2509 // RVV Types
2510 #define RVV_TYPE(Name, Id, SingletonId) Id,
2511 #include "clang/Basic/RISCVVTypes.def"
2512 // All other builtin types
2513 #define BUILTIN_TYPE(Id, SingletonId) Id,
2514 #define LAST_BUILTIN_TYPE(Id) LastKind = Id
2515 #include "clang/AST/BuiltinTypes.def"
2516  };
2517 
2518 private:
2519  friend class ASTContext; // ASTContext creates these.
2520 
2521  BuiltinType(Kind K)
2522  : Type(Builtin, QualType(),
2523  K == Dependent ? TypeDependence::DependentInstantiation
2524  : TypeDependence::None) {
2525  BuiltinTypeBits.Kind = K;
2526  }
2527 
2528 public:
2529  Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
2530  StringRef getName(const PrintingPolicy &Policy) const;
2531 
2532  const char *getNameAsCString(const PrintingPolicy &Policy) const {
2533  // The StringRef is null-terminated.
2534  StringRef str = getName(Policy);
2535  assert(!str.empty() && str.data()[str.size()] == '\0');
2536  return str.data();
2537  }
2538 
2539  bool isSugared() const { return false; }
2540  QualType desugar() const { return QualType(this, 0); }
2541 
2542  bool isInteger() const {
2543  return getKind() >= Bool && getKind() <= Int128;
2544  }
2545 
2546  bool isSignedInteger() const {
2547  return getKind() >= Char_S && getKind() <= Int128;
2548  }
2549 
2550  bool isUnsignedInteger() const {
2551  return getKind() >= Bool && getKind() <= UInt128;
2552  }
2553 
2554  bool isFloatingPoint() const {
2555  return getKind() >= Half && getKind() <= Ibm128;
2556  }
2557 
2558  /// Determines whether the given kind corresponds to a placeholder type.
2559  static bool isPlaceholderTypeKind(Kind K) {
2560  return K >= Overload;
2561  }
2562 
2563  /// Determines whether this type is a placeholder type, i.e. a type
2564  /// which cannot appear in arbitrary positions in a fully-formed
2565  /// expression.
2566  bool isPlaceholderType() const {
2567  return isPlaceholderTypeKind(getKind());
2568  }
2569 
2570  /// Determines whether this type is a placeholder type other than
2571  /// Overload. Most placeholder types require only syntactic
2572  /// information about their context in order to be resolved (e.g.
2573  /// whether it is a call expression), which means they can (and
2574  /// should) be resolved in an earlier "phase" of analysis.
2575  /// Overload expressions sometimes pick up further information
2576  /// from their context, like whether the context expects a
2577  /// specific function-pointer type, and so frequently need
2578  /// special treatment.
2580  return getKind() > Overload;
2581  }
2582 
2583  static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2584 };
2585 
2586 /// Complex values, per C99 6.2.5p11. This supports the C99 complex
2587 /// types (_Complex float etc) as well as the GCC integer complex extensions.
2588 class ComplexType : public Type, public llvm::FoldingSetNode {
2589  friend class ASTContext; // ASTContext creates these.
2590 
2591  QualType ElementType;
2592 
2593  ComplexType(QualType Element, QualType CanonicalPtr)
2594  : Type(Complex, CanonicalPtr, Element->getDependence()),
2595  ElementType(Element) {}
2596 
2597 public:
2598  QualType getElementType() const { return ElementType; }
2599 
2600  bool isSugared() const { return false; }
2601  QualType desugar() const { return QualType(this, 0); }
2602 
2603  void Profile(llvm::FoldingSetNodeID &ID) {
2605  }
2606 
2607  static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
2608  ID.AddPointer(Element.getAsOpaquePtr());
2609  }
2610 
2611  static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2612 };
2613 
2614 /// Sugar for parentheses used when specifying types.
2615 class ParenType : public Type, public llvm::FoldingSetNode {
2616  friend class ASTContext; // ASTContext creates these.
2617 
2618  QualType Inner;
2619 
2620  ParenType(QualType InnerType, QualType CanonType)
2621  : Type(Paren, CanonType, InnerType->getDependence()), Inner(InnerType) {}
2622 
2623 public:
2624  QualType getInnerType() const { return Inner; }
2625 
2626  bool isSugared() const { return true; }
2627  QualType desugar() const { return getInnerType(); }
2628 
2629  void Profile(llvm::FoldingSetNodeID &ID) {
2630  Profile(ID, getInnerType());
2631  }
2632 
2633  static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
2634  Inner.Profile(ID);
2635  }
2636 
2637  static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2638 };
2639 
2640 /// PointerType - C99 6.7.5.1 - Pointer Declarators.
2641 class PointerType : public Type, public llvm::FoldingSetNode {
2642  friend class ASTContext; // ASTContext creates these.
2643 
2644  QualType PointeeType;
2645 
2646  PointerType(QualType Pointee, QualType CanonicalPtr)
2647  : Type(Pointer, CanonicalPtr, Pointee->getDependence()),
2648  PointeeType(Pointee) {}
2649 
2650 public:
2651  QualType getPointeeType() const { return PointeeType; }
2652 
2653  bool isSugared() const { return false; }
2654  QualType desugar() const { return QualType(this, 0); }
2655 
2656  void Profile(llvm::FoldingSetNodeID &ID) {
2658  }
2659 
2660  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2661  ID.AddPointer(Pointee.getAsOpaquePtr());
2662  }
2663 
2664  static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2665 };
2666 
2667 /// Represents a type which was implicitly adjusted by the semantic
2668 /// engine for arbitrary reasons. For example, array and function types can
2669 /// decay, and function types can have their calling conventions adjusted.
2670 class AdjustedType : public Type, public llvm::FoldingSetNode {
2671  QualType OriginalTy;
2672  QualType AdjustedTy;
2673 
2674 protected:
2675  friend class ASTContext; // ASTContext creates these.
2676 
2677  AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
2678  QualType CanonicalPtr)
2679  : Type(TC, CanonicalPtr, OriginalTy->getDependence()),
2680  OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
2681 
2682 public:
2683  QualType getOriginalType() const { return OriginalTy; }
2684  QualType getAdjustedType() const { return AdjustedTy; }
2685 
2686  bool isSugared() const { return true; }
2687  QualType desugar() const { return AdjustedTy; }
2688 
2689  void Profile(llvm::FoldingSetNodeID &ID) {
2690  Profile(ID, OriginalTy, AdjustedTy);
2691  }
2692 
2693  static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
2694  ID.AddPointer(Orig.getAsOpaquePtr());
2695  ID.AddPointer(New.getAsOpaquePtr());
2696  }
2697 
2698  static bool classof(const Type *T) {
2699  return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
2700  }
2701 };
2702 
2703 /// Represents a pointer type decayed from an array or function type.
2704 class DecayedType : public AdjustedType {
2705  friend class ASTContext; // ASTContext creates these.
2706 
2707  inline
2708  DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);
2709 
2710 public:
2712 
2713  inline QualType getPointeeType() const;
2714 
2715  static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
2716 };
2717 
2718 /// Pointer to a block type.
2719 /// This type is to represent types syntactically represented as
2720 /// "void (^)(int)", etc. Pointee is required to always be a function type.
2721 class BlockPointerType : public Type, public llvm::FoldingSetNode {
2722  friend class ASTContext; // ASTContext creates these.
2723 
2724  // Block is some kind of pointer type
2725  QualType PointeeType;
2726 
2727  BlockPointerType(QualType Pointee, QualType CanonicalCls)
2728  : Type(BlockPointer, CanonicalCls, Pointee->getDependence()),
2729  PointeeType(Pointee) {}
2730 
2731 public:
2732  // Get the pointee type. Pointee is required to always be a function type.
2733  QualType getPointeeType() const { return PointeeType; }
2734 
2735  bool isSugared() const { return false; }
2736  QualType desugar() const { return QualType(this, 0); }
2737 
2738  void Profile(llvm::FoldingSetNodeID &ID) {
2740  }
2741 
2742  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2743  ID.AddPointer(Pointee.getAsOpaquePtr());
2744  }
2745 
2746  static bool classof(const Type *T) {
2747  return T->getTypeClass() == BlockPointer;
2748  }
2749 };
2750 
2751 /// Base for LValueReferenceType and RValueReferenceType
2752 class ReferenceType : public Type, public llvm::FoldingSetNode {
2753  QualType PointeeType;
2754 
2755 protected:
2756  ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
2757  bool SpelledAsLValue)
2758  : Type(tc, CanonicalRef, Referencee->getDependence()),
2759  PointeeType(Referencee) {
2760  ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
2761  ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
2762  }
2763 
2764 public:
2765  bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
2766  bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }
2767 
2768  QualType getPointeeTypeAsWritten() const { return PointeeType; }
2769 
2771  // FIXME: this might strip inner qualifiers; okay?
2772  const ReferenceType *T = this;
2773  while (T->isInnerRef())
2774  T = T->PointeeType->castAs<ReferenceType>();
2775  return T->PointeeType;
2776  }
2777 
2778  void Profile(llvm::FoldingSetNodeID &ID) {
2779  Profile(ID, PointeeType, isSpelledAsLValue());
2780  }
2781 
2782  static void Profile(llvm::FoldingSetNodeID &ID,
2783  QualType Referencee,
2784  bool SpelledAsLValue) {
2785  ID.AddPointer(Referencee.getAsOpaquePtr());
2786  ID.AddBoolean(SpelledAsLValue);
2787  }
2788 
2789  static bool classof(const Type *T) {
2790  return T->getTypeClass() == LValueReference ||
2791  T->getTypeClass() == RValueReference;
2792  }
2793 };
2794 
2795 /// An lvalue reference type, per C++11 [dcl.ref].
2797  friend class ASTContext; // ASTContext creates these
2798 
2799  LValueReferenceType(QualType Referencee, QualType CanonicalRef,
2800  bool SpelledAsLValue)
2801  : ReferenceType(LValueReference, Referencee, CanonicalRef,
2802  SpelledAsLValue) {}
2803 
2804 public:
2805  bool isSugared() const { return false; }
2806  QualType desugar() const { return QualType(this, 0); }
2807 
2808  static bool classof(const Type *T) {
2809  return T->getTypeClass() == LValueReference;
2810  }
2811 };
2812 
2813 /// An rvalue reference type, per C++11 [dcl.ref].
2815  friend class ASTContext; // ASTContext creates these
2816 
2817  RValueReferenceType(QualType Referencee, QualType CanonicalRef)
2818  : ReferenceType(RValueReference, Referencee, CanonicalRef, false) {}
2819 
2820 public:
2821  bool isSugared() const { return false; }
2822  QualType desugar() const { return QualType(this, 0); }
2823 
2824  static bool classof(const Type *T) {
2825  return T->getTypeClass() == RValueReference;
2826  }
2827 };
2828 
2829 /// A pointer to member type per C++ 8.3.3 - Pointers to members.
2830 ///
2831 /// This includes both pointers to data members and pointer to member functions.
2832 class MemberPointerType : public Type, public llvm::FoldingSetNode {
2833  friend class ASTContext; // ASTContext creates these.
2834 
2835  QualType PointeeType;
2836 
2837  /// The class of which the pointee is a member. Must ultimately be a
2838  /// RecordType, but could be a typedef or a template parameter too.
2839  const Type *Class;
2840 
2841  MemberPointerType(QualType Pointee, const Type *Cls, QualType CanonicalPtr)
2842  : Type(MemberPointer, CanonicalPtr,
2843  (Cls->getDependence() & ~TypeDependence::VariablyModified) |
2844  Pointee->getDependence()),
2845  PointeeType(Pointee), Class(Cls) {}
2846 
2847 public:
2848  QualType getPointeeType() const { return PointeeType; }
2849 
2850  /// Returns true if the member type (i.e. the pointee type) is a
2851  /// function type rather than a data-member type.
2853  return PointeeType->isFunctionProtoType();
2854  }
2855 
2856  /// Returns true if the member type (i.e. the pointee type) is a
2857  /// data type rather than a function type.
2858  bool isMemberDataPointer() const {
2859  return !PointeeType->isFunctionProtoType();
2860  }
2861 
2862  const Type *getClass() const { return Class; }
2864 
2865  bool isSugared() const { return false; }
2866  QualType desugar() const { return QualType(this, 0); }
2867 
2868  void Profile(llvm::FoldingSetNodeID &ID) {
2870  }
2871 
2872  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee,
2873  const Type *Class) {
2874  ID.AddPointer(Pointee.getAsOpaquePtr());
2875  ID.AddPointer(Class);
2876  }
2877 
2878  static bool classof(const Type *T) {
2879  return T->getTypeClass() == MemberPointer;
2880  }
2881 };
2882 
2883 /// Represents an array type, per C99 6.7.5.2 - Array Declarators.
2884 class ArrayType : public Type, public llvm::FoldingSetNode {
2885 public:
2886  /// Capture whether this is a normal array (e.g. int X[4])
2887  /// an array with a static size (e.g. int X[static 4]), or an array
2888  /// with a star size (e.g. int X[*]).
2889  /// 'static' is only allowed on function parameters.
2892  };
2893 
2894 private:
2895  /// The element type of the array.
2896  QualType ElementType;
2897 
2898 protected:
2899  friend class ASTContext; // ASTContext creates these.
2900 
2902  unsigned tq, const Expr *sz = nullptr);
2903 
2904 public:
2905  QualType getElementType() const { return ElementType; }
2906 
2908  return ArraySizeModifier(ArrayTypeBits.SizeModifier);
2909  }
2910 
2913  }
2914 
2915  unsigned getIndexTypeCVRQualifiers() const {
2916  return ArrayTypeBits.IndexTypeQuals;
2917  }
2918 
2919  static bool classof(const Type *T) {
2920  return T->getTypeClass() == ConstantArray ||
2921  T->getTypeClass() == VariableArray ||
2922  T->getTypeClass() == IncompleteArray ||
2923  T->getTypeClass() == DependentSizedArray;
2924  }
2925 };
2926 
2927 /// Represents the canonical version of C arrays with a specified constant size.
2928 /// For example, the canonical type for 'int A[4 + 4*100]' is a
2929 /// ConstantArrayType where the element type is 'int' and the size is 404.
2931  : public ArrayType,
2932  private llvm::TrailingObjects<ConstantArrayType, const Expr *> {
2933  friend class ASTContext; // ASTContext creates these.
2934  friend TrailingObjects;
2935 
2936  llvm::APInt Size; // Allows us to unique the type.
2937 
2938  ConstantArrayType(QualType et, QualType can, const llvm::APInt &size,
2939  const Expr *sz, ArraySizeModifier sm, unsigned tq)
2940  : ArrayType(ConstantArray, et, can, sm, tq, sz), Size(size) {
2941  ConstantArrayTypeBits.HasStoredSizeExpr = sz != nullptr;
2942  if (ConstantArrayTypeBits.HasStoredSizeExpr) {
2943  assert(!can.isNull() && "canonical constant array should not have size");
2944  *getTrailingObjects<const Expr*>() = sz;
2945  }
2946  }
2947 
2948  unsigned numTrailingObjects(OverloadToken<const Expr*>) const {
2949  return ConstantArrayTypeBits.HasStoredSizeExpr;
2950  }
2951 
2952 public:
2953  const llvm::APInt &getSize() const { return Size; }
2954  const Expr *getSizeExpr() const {
2955  return ConstantArrayTypeBits.HasStoredSizeExpr
2956  ? *getTrailingObjects<const Expr *>()
2957  : nullptr;
2958  }
2959  bool isSugared() const { return false; }
2960  QualType desugar() const { return QualType(this, 0); }
2961 
2962  /// Determine the number of bits required to address a member of
2963  // an array with the given element type and number of elements.
2964  static unsigned getNumAddressingBits(const ASTContext &Context,
2965  QualType ElementType,
2966  const llvm::APInt &NumElements);
2967 
2968  /// Determine the maximum number of active bits that an array's size
2969  /// can require, which limits the maximum size of the array.
2970  static unsigned getMaxSizeBits(const ASTContext &Context);
2971 
2972  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx) {
2975  }
2976 
2977  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx,
2978  QualType ET, const llvm::APInt &ArraySize,
2979  const Expr *SizeExpr, ArraySizeModifier SizeMod,
2980  unsigned TypeQuals);
2981 
2982  static bool classof(const Type *T) {
2983  return T->getTypeClass() == ConstantArray;
2984  }
2985 };
2986 
2987 /// Represents a C array with an unspecified size. For example 'int A[]' has
2988 /// an IncompleteArrayType where the element type is 'int' and the size is
2989 /// unspecified.
2991  friend class ASTContext; // ASTContext creates these.
2992 
2994  ArraySizeModifier sm, unsigned tq)
2995  : ArrayType(IncompleteArray, et, can, sm, tq) {}
2996 
2997 public:
2998  friend class StmtIteratorBase;
2999 
3000  bool isSugared() const { return false; }
3001  QualType desugar() const { return QualType(this, 0); }
3002 
3003  static bool classof(const Type *T) {
3004  return T->getTypeClass() == IncompleteArray;
3005  }
3006 
3007  void Profile(llvm::FoldingSetNodeID &ID) {
3010  }
3011 
3012  static void Profile(llvm::FoldingSetNodeID &ID, QualType ET,
3013  ArraySizeModifier SizeMod, unsigned TypeQuals) {
3014  ID.AddPointer(ET.getAsOpaquePtr());
3015  ID.AddInteger(SizeMod);
3016  ID.AddInteger(TypeQuals);
3017  }
3018 };
3019 
3020 /// Represents a C array with a specified size that is not an
3021 /// integer-constant-expression. For example, 'int s[x+foo()]'.
3022 /// Since the size expression is an arbitrary expression, we store it as such.
3023 ///
3024 /// Note: VariableArrayType's aren't uniqued (since the expressions aren't) and
3025 /// should not be: two lexically equivalent variable array types could mean
3026 /// different things, for example, these variables do not have the same type
3027 /// dynamically:
3028 ///
3029 /// void foo(int x) {
3030 /// int Y[x];
3031 /// ++x;
3032 /// int Z[x];
3033 /// }
3035  friend class ASTContext; // ASTContext creates these.
3036 
3037  /// An assignment-expression. VLA's are only permitted within
3038  /// a function block.
3039  Stmt *SizeExpr;
3040 
3041  /// The range spanned by the left and right array brackets.
3042  SourceRange Brackets;
3043 
3045  ArraySizeModifier sm, unsigned tq,
3046  SourceRange brackets)
3047  : ArrayType(VariableArray, et, can, sm, tq, e),
3048  SizeExpr((Stmt*) e), Brackets(brackets) {}
3049 
3050 public:
3051  friend class StmtIteratorBase;
3052 
3053  Expr *getSizeExpr() const {
3054  // We use C-style casts instead of cast<> here because we do not wish
3055  // to have a dependency of Type.h on Stmt.h/Expr.h.
3056  return (Expr*) SizeExpr;
3057  }
3058 
3059  SourceRange getBracketsRange() const { return Brackets; }
3060  SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
3061  SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
3062 
3063  bool isSugared() const { return false; }
3064  QualType desugar() const { return QualType(this, 0); }
3065 
3066  static bool classof(const Type *T) {
3067  return T->getTypeClass() == VariableArray;
3068  }
3069 
3070  void Profile(llvm::FoldingSetNodeID &ID) {
3071  llvm_unreachable("Cannot unique VariableArrayTypes.");
3072  }
3073 };
3074 
3075 /// Represents an array type in C++ whose size is a value-dependent expression.
3076 ///
3077 /// For example:
3078 /// \code
3079 /// template<typename T, int Size>
3080 /// class array {
3081 /// T data[Size];
3082 /// };
3083 /// \endcode
3084 ///
3085 /// For these types, we won't actually know what the array bound is
3086 /// until template instantiation occurs, at which point this will
3087 /// become either a ConstantArrayType or a VariableArrayType.
3089  friend class ASTContext; // ASTContext creates these.
3090 
3091  const ASTContext &Context;
3092 
3093  /// An assignment expression that will instantiate to the
3094  /// size of the array.
3095  ///
3096  /// The expression itself might be null, in which case the array
3097  /// type will have its size deduced from an initializer.
3098  Stmt *SizeExpr;
3099 
3100  /// The range spanned by the left and right array brackets.
3101  SourceRange Brackets;
3102 
3103  DependentSizedArrayType(const ASTContext &Context, QualType et, QualType can,
3104  Expr *e, ArraySizeModifier sm, unsigned tq,
3105  SourceRange brackets);
3106 
3107 public:
3108  friend class StmtIteratorBase;
3109 
3110  Expr *getSizeExpr() const {
3111  // We use C-style casts instead of cast<> here because we do not wish
3112  // to have a dependency of Type.h on Stmt.h/Expr.h.
3113  return (Expr*) SizeExpr;
3114  }
3115 
3116  SourceRange getBracketsRange() const { return Brackets; }
3117  SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
3118  SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
3119 
3120  bool isSugared() const { return false; }
3121  QualType desugar() const { return QualType(this, 0); }
3122 
3123  static bool classof(const Type *T) {
3124  return T->getTypeClass() == DependentSizedArray;
3125  }
3126 
3127  void Profile(llvm::FoldingSetNodeID &ID) {
3128  Profile(ID, Context, getElementType(),
3130  }
3131 
3132  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3133  QualType ET, ArraySizeModifier SizeMod,
3134  unsigned TypeQuals, Expr *E);
3135 };
3136 
3137 /// Represents an extended address space qualifier where the input address space
3138 /// value is dependent. Non-dependent address spaces are not represented with a
3139 /// special Type subclass; they are stored on an ExtQuals node as part of a QualType.
3140 ///
3141 /// For example:
3142 /// \code
3143 /// template<typename T, int AddrSpace>
3144 /// class AddressSpace {
3145 /// typedef T __attribute__((address_space(AddrSpace))) type;
3146 /// }
3147 /// \endcode
3148 class DependentAddressSpaceType : public Type, public llvm::FoldingSetNode {
3149  friend class ASTContext;
3150 
3151  const ASTContext &Context;
3152  Expr *AddrSpaceExpr;
3153  QualType PointeeType;
3154  SourceLocation loc;
3155 
3156  DependentAddressSpaceType(const ASTContext &Context, QualType PointeeType,
3157  QualType can, Expr *AddrSpaceExpr,
3158  SourceLocation loc);
3159 
3160 public:
3161  Expr *getAddrSpaceExpr() const { return AddrSpaceExpr; }
3162  QualType getPointeeType() const { return PointeeType; }
3163  SourceLocation getAttributeLoc() const { return loc; }
3164 
3165  bool isSugared() const { return false; }
3166  QualType desugar() const { return QualType(this, 0); }
3167 
3168  static bool classof(const Type *T) {
3169  return T->getTypeClass() == DependentAddressSpace;
3170  }
3171 
3172  void Profile(llvm::FoldingSetNodeID &ID) {
3173  Profile(ID, Context, getPointeeType(), getAddrSpaceExpr());
3174  }
3175 
3176  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3177  QualType PointeeType, Expr *AddrSpaceExpr);
3178 };
3179 
3180 /// Represents an extended vector type where either the type or size is
3181 /// dependent.
3182 ///
3183 /// For example:
3184 /// \code
3185 /// template<typename T, int Size>
3186 /// class vector {
3187 /// typedef T __attribute__((ext_vector_type(Size))) type;
3188 /// }
3189 /// \endcode
3190 class DependentSizedExtVectorType : public Type, public llvm::FoldingSetNode {
3191  friend class ASTContext;
3192 
3193  const ASTContext &Context;
3194  Expr *SizeExpr;
3195 
3196  /// The element type of the array.
3197  QualType ElementType;
3198 
3199  SourceLocation loc;
3200 
3201  DependentSizedExtVectorType(const ASTContext &Context, QualType ElementType,
3202  QualType can, Expr *SizeExpr, SourceLocation loc);
3203 
3204 public:
3205  Expr *getSizeExpr() const { return SizeExpr; }
3206  QualType getElementType() const { return ElementType; }
3207  SourceLocation getAttributeLoc() const { return loc; }
3208 
3209  bool isSugared() const { return false; }
3210  QualType desugar() const { return QualType(this, 0); }
3211 
3212  static bool classof(const Type *T) {
3213  return T->getTypeClass() == DependentSizedExtVector;
3214  }
3215 
3216  void Profile(llvm::FoldingSetNodeID &ID) {
3217  Profile(ID, Context, getElementType(), getSizeExpr());
3218  }
3219 
3220  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3221  QualType ElementType, Expr *SizeExpr);
3222 };
3223 
3224 
3225 /// Represents a GCC generic vector type. This type is created using
3226 /// __attribute__((vector_size(n)), where "n" specifies the vector size in
3227 /// bytes; or from an Altivec __vector or vector declaration.
3228 /// Since the constructor takes the number of vector elements, the
3229 /// client is responsible for converting the size into the number of elements.
3230 class VectorType : public Type, public llvm::FoldingSetNode {
3231 public:
3232  enum VectorKind {
3233  /// not a target-specific vector type
3235 
3236  /// is AltiVec vector
3238 
3239  /// is AltiVec 'vector Pixel'
3241 
3242  /// is AltiVec 'vector bool ...'
3244 
3245  /// is ARM Neon vector
3247 
3248  /// is ARM Neon polynomial vector
3250 
3251  /// is AArch64 SVE fixed-length data vector
3253 
3254  /// is AArch64 SVE fixed-length predicate vector
3256  };
3257 
3258 protected:
3259  friend class ASTContext; // ASTContext creates these.
3260 
3261  /// The element type of the vector.
3263 
3264  VectorType(QualType vecType, unsigned nElements, QualType canonType,
3265  VectorKind vecKind);
3266 
3267  VectorType(TypeClass tc, QualType vecType, unsigned nElements,
3268  QualType canonType, VectorKind vecKind);
3269 
3270 public:
3272  unsigned getNumElements() const { return VectorTypeBits.NumElements; }
3273 
3274  bool isSugared() const { return false; }
3275  QualType desugar() const { return QualType(this, 0); }
3276 
3278  return VectorKind(VectorTypeBits.VecKind);
3279  }
3280 
3281  void Profile(llvm::FoldingSetNodeID &ID) {
3284  }
3285 
3286  static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
3287  unsigned NumElements, TypeClass TypeClass,
3288  VectorKind VecKind) {
3289  ID.AddPointer(ElementType.getAsOpaquePtr());
3290  ID.AddInteger(NumElements);
3291  ID.AddInteger(TypeClass);
3292  ID.AddInteger(VecKind);
3293  }
3294 
3295  static bool classof(const Type *T) {
3296  return T->getTypeClass() == Vector || T->getTypeClass() == ExtVector;
3297  }
3298 };
3299 
3300 /// Represents a vector type where either the type or size is dependent.
3301 ////
3302 /// For example:
3303 /// \code
3304 /// template<typename T, int Size>
3305 /// class vector {
3306 /// typedef T __attribute__((vector_size(Size))) type;
3307 /// }
3308 /// \endcode
3309 class DependentVectorType : public Type, public llvm::FoldingSetNode {
3310  friend class ASTContext;
3311 
3312  const ASTContext &Context;
3313  QualType ElementType;
3314  Expr *SizeExpr;
3315  SourceLocation Loc;
3316 
3317  DependentVectorType(const ASTContext &Context, QualType ElementType,
3318  QualType CanonType, Expr *SizeExpr,
3319  SourceLocation Loc, VectorType::VectorKind vecKind);
3320 
3321 public:
3322  Expr *getSizeExpr() const { return SizeExpr; }
3323  QualType getElementType() const { return ElementType; }
3324  SourceLocation getAttributeLoc() const { return Loc; }
3326  return VectorType::VectorKind(VectorTypeBits.VecKind);
3327  }
3328 
3329  bool isSugared() const { return false; }
3330  QualType desugar() const { return QualType(this, 0); }
3331 
3332  static bool classof(const Type *T) {
3333  return T->getTypeClass() == DependentVector;
3334  }
3335 
3336  void Profile(llvm::FoldingSetNodeID &ID) {
3337  Profile(ID, Context, getElementType(), getSizeExpr(), getVectorKind());
3338  }
3339 
3340  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3341  QualType ElementType, const Expr *SizeExpr,
3342  VectorType::VectorKind VecKind);
3343 };
3344 
3345 /// ExtVectorType - Extended vector type. This type is created using
3346 /// __attribute__((ext_vector_type(n)), where "n" is the number of elements.
3347 /// Unlike vector_size, ext_vector_type is only allowed on typedef's. This
3348 /// class enables syntactic extensions, like Vector Components for accessing
3349 /// points (as .xyzw), colors (as .rgba), and textures (modeled after OpenGL
3350 /// Shading Language).
3351 class ExtVectorType : public VectorType {
3352  friend class ASTContext; // ASTContext creates these.
3353 
3354  ExtVectorType(QualType vecType, unsigned nElements, QualType canonType)
3355  : VectorType(ExtVector, vecType, nElements, canonType, GenericVector) {}
3356 
3357 public:
3358  static int getPointAccessorIdx(char c) {
3359  switch (c) {
3360  default: return -1;
3361  case 'x': case 'r': return 0;
3362  case 'y': case 'g': return 1;
3363  case 'z': case 'b': return 2;
3364  case 'w': case 'a': return 3;
3365  }
3366  }
3367 
3368  static int getNumericAccessorIdx(char c) {
3369  switch (c) {
3370  default: return -1;
3371  case '0': return 0;
3372  case '1': return 1;
3373  case '2': return 2;
3374  case '3': return 3;
3375  case '4': return 4;
3376  case '5': return 5;
3377  case '6': return 6;
3378  case '7': return 7;
3379  case '8': return 8;
3380  case '9': return 9;
3381  case 'A':
3382  case 'a': return 10;
3383  case 'B':
3384  case 'b': return 11;
3385  case 'C':
3386  case 'c': return 12;
3387  case 'D':
3388  case 'd': return 13;
3389  case 'E':
3390  case 'e': return 14;
3391  case 'F':
3392  case 'f': return 15;
3393  }
3394  }
3395 
3396  static int getAccessorIdx(char c, bool isNumericAccessor) {
3397  if (isNumericAccessor)
3398  return getNumericAccessorIdx(c);
3399  else
3400  return getPointAccessorIdx(c);
3401  }
3402 
3403  bool isAccessorWithinNumElements(char c, bool isNumericAccessor) const {
3404  if (int idx = getAccessorIdx(c, isNumericAccessor)+1)
3405  return unsigned(idx-1) < getNumElements();
3406  return false;
3407  }
3408 
3409  bool isSugared() const { return false; }
3410  QualType desugar() const { return QualType(this, 0); }
3411 
3412  static bool classof(const Type *T) {
3413  return T->getTypeClass() == ExtVector;
3414  }
3415 };
3416 
3417 /// Represents a matrix type, as defined in the Matrix Types clang extensions.
3418 /// __attribute__((matrix_type(rows, columns))), where "rows" specifies
3419 /// number of rows and "columns" specifies the number of columns.
3420 class MatrixType : public Type, public llvm::FoldingSetNode {
3421 protected:
3422  friend class ASTContext;
3423 
3424  /// The element type of the matrix.
3426 
3427  MatrixType(QualType ElementTy, QualType CanonElementTy);
3428 
3429  MatrixType(TypeClass TypeClass, QualType ElementTy, QualType CanonElementTy,
3430  const Expr *RowExpr = nullptr, const Expr *ColumnExpr = nullptr);
3431 
3432 public:
3433  /// Returns type of the elements being stored in the matrix
3435 
3436  /// Valid elements types are the following:
3437  /// * an integer type (as in C2x 6.2.5p19), but excluding enumerated types
3438  /// and _Bool
3439  /// * the standard floating types float or double
3440  /// * a half-precision floating point type, if one is supported on the target
3441  static bool isValidElementType(QualType T) {
3442  return T->isDependentType() ||
3443  (T->isRealType() && !T->isBooleanType() && !T->isEnumeralType());
3444  }
3445 
3446  bool isSugared() const { return false; }
3447  QualType desugar() const { return QualType(this, 0); }
3448 
3449  static bool classof(const Type *T) {
3450  return T->getTypeClass() == ConstantMatrix ||
3451  T->getTypeClass() == DependentSizedMatrix;
3452  }
3453 };
3454 
3455 /// Represents a concrete matrix type with constant number of rows and columns
3456 class ConstantMatrixType final : public MatrixType {
3457 protected:
3458  friend class ASTContext;
3459 
3460  /// Number of rows and columns.
3461  unsigned NumRows;
3462  unsigned NumColumns;
3463 
3464  static constexpr unsigned MaxElementsPerDimension = (1 << 20) - 1;
3465 
3466  ConstantMatrixType(QualType MatrixElementType, unsigned NRows,
3467  unsigned NColumns, QualType CanonElementType);
3468 
3469  ConstantMatrixType(TypeClass typeClass, QualType MatrixType, unsigned NRows,
3470  unsigned NColumns, QualType CanonElementType);
3471 
3472 public:
3473  /// Returns the number of rows in the matrix.
3474  unsigned getNumRows() const { return NumRows; }
3475 
3476  /// Returns the number of columns in the matrix.
3477  unsigned getNumColumns() const { return NumColumns; }
3478 
3479  /// Returns the number of elements required to embed the matrix into a vector.
3480  unsigned getNumElementsFlattened() const {
3481  return getNumRows() * getNumColumns();
3482  }
3483 
3484  /// Returns true if \p NumElements is a valid matrix dimension.
3485  static constexpr bool isDimensionValid(size_t NumElements) {
3486  return NumElements > 0 && NumElements <= MaxElementsPerDimension;
3487  }
3488 
3489  /// Returns the maximum number of elements per dimension.
3490  static constexpr unsigned getMaxElementsPerDimension() {
3491  return MaxElementsPerDimension;
3492  }
3493 
3494  void Profile(llvm::FoldingSetNodeID &ID) {
3496  getTypeClass());
3497  }
3498 
3499  static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
3500  unsigned NumRows, unsigned NumColumns,
3501  TypeClass TypeClass) {
3502  ID.AddPointer(ElementType.getAsOpaquePtr());
3503  ID.AddInteger(NumRows);
3504  ID.AddInteger(NumColumns);
3505  ID.AddInteger(TypeClass);
3506  }
3507 
3508  static bool classof(const Type *T) {
3509  return T->getTypeClass() == ConstantMatrix;
3510  }
3511 };
3512 
3513 /// Represents a matrix type where the type and the number of rows and columns
3514 /// is dependent on a template.
3515 class DependentSizedMatrixType final : public MatrixType {
3516  friend class ASTContext;
3517 
3518  const ASTContext &Context;
3519  Expr *RowExpr;
3520  Expr *ColumnExpr;
3521 
3522  SourceLocation loc;
3523 
3525  QualType CanonicalType, Expr *RowExpr,
3526  Expr *ColumnExpr, SourceLocation loc);
3527 
3528 public:
3529  Expr *getRowExpr() const { return RowExpr; }
3530  Expr *getColumnExpr() const { return ColumnExpr; }
3531  SourceLocation getAttributeLoc() const { return loc; }
3532 
3533  static bool classof(const Type *T) {
3534  return T->getTypeClass() == DependentSizedMatrix;
3535  }
3536 
3537  void Profile(llvm::FoldingSetNodeID &ID) {
3538  Profile(ID, Context, getElementType(), getRowExpr(), getColumnExpr());
3539  }
3540 
3541  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3542  QualType ElementType, Expr *RowExpr, Expr *ColumnExpr);
3543 };
3544 
3545 /// FunctionType - C99 6.7.5.3 - Function Declarators. This is the common base
3546 /// class of FunctionNoProtoType and FunctionProtoType.
3547 class FunctionType : public Type {
3548  // The type returned by the function.
3549  QualType ResultType;
3550 
3551 public:
3552  /// Interesting information about a specific parameter that can't simply
3553  /// be reflected in parameter's type. This is only used by FunctionProtoType
3554  /// but is in FunctionType to make this class available during the
3555  /// specification of the bases of FunctionProtoType.
3556  ///
3557  /// It makes sense to model language features this way when there's some
3558  /// sort of parameter-specific override (such as an attribute) that
3559  /// affects how the function is called. For example, the ARC ns_consumed
3560  /// attribute changes whether a parameter is passed at +0 (the default)
3561  /// or +1 (ns_consumed). This must be reflected in the function type,
3562  /// but isn't really a change to the parameter type.
3563  ///
3564  /// One serious disadvantage of modelling language features this way is
3565  /// that they generally do not work with language features that attempt
3566  /// to destructure types. For example, template argument deduction will
3567  /// not be able to match a parameter declared as
3568  /// T (*)(U)
3569  /// against an argument of type
3570  /// void (*)(__attribute__((ns_consumed)) id)
3571  /// because the substitution of T=void, U=id into the former will
3572  /// not produce the latter.
3574  enum {
3575  ABIMask = 0x0F,
3576  IsConsumed = 0x10,
3577  HasPassObjSize = 0x20,
3578  IsNoEscape = 0x40,
3579  };
3580  unsigned char Data = 0;
3581 
3582  public:
3583  ExtParameterInfo() = default;
3584 
3585  /// Return the ABI treatment of this parameter.
3586  ParameterABI getABI() const { return ParameterABI(Data & ABIMask); }
3588  ExtParameterInfo copy = *this;
3589  copy.Data = (copy.Data & ~ABIMask) | unsigned(kind);
3590  return copy;
3591  }
3592 
3593  /// Is this parameter considered "consumed" by Objective-C ARC?
3594  /// Consumed parameters must have retainable object type.
3595  bool isConsumed() const { return (Data & IsConsumed); }
3596  ExtParameterInfo withIsConsumed(bool consumed) const {
3597  ExtParameterInfo copy = *this;
3598  if (consumed)
3599  copy.Data |= IsConsumed;
3600  else
3601  copy.Data &= ~IsConsumed;
3602  return copy;
3603  }
3604 
3605  bool hasPassObjectSize() const { return Data & HasPassObjSize; }
3607  ExtParameterInfo Copy = *this;
3608  Copy.Data |= HasPassObjSize;
3609  return Copy;
3610  }
3611 
3612  bool isNoEscape() const { return Data & IsNoEscape; }
3613  ExtParameterInfo withIsNoEscape(bool NoEscape) const {
3614  ExtParameterInfo Copy = *this;
3615  if (NoEscape)
3616  Copy.Data |= IsNoEscape;
3617  else
3618  Copy.Data &= ~IsNoEscape;
3619  return Copy;
3620  }
3621 
3622  unsigned char getOpaqueValue() const { return Data; }
3623  static ExtParameterInfo getFromOpaqueValue(unsigned char data) {
3624  ExtParameterInfo result;
3625  result.Data = data;
3626  return result;
3627  }
3628 
3630  return lhs.Data == rhs.Data;
3631  }
3632 
3634  return lhs.Data != rhs.Data;
3635  }
3636  };
3637 
3638  /// A class which abstracts out some details necessary for
3639  /// making a call.
3640  ///
3641  /// It is not actually used directly for storing this information in
3642  /// a FunctionType, although FunctionType does currently use the
3643  /// same bit-pattern.
3644  ///
3645  // If you add a field (say Foo), other than the obvious places (both,
3646  // constructors, compile failures), what you need to update is
3647  // * Operator==
3648  // * getFoo
3649  // * withFoo
3650  // * functionType. Add Foo, getFoo.
3651  // * ASTContext::getFooType
3652  // * ASTContext::mergeFunctionTypes
3653  // * FunctionNoProtoType::Profile
3654  // * FunctionProtoType::Profile
3655  // * TypePrinter::PrintFunctionProto
3656  // * AST read and write
3657  // * Codegen
3658  class ExtInfo {
3659  friend class FunctionType;
3660 
3661  // Feel free to rearrange or add bits, but if you go over 16, you'll need to
3662  // adjust the Bits field below, and if you add bits, you'll need to adjust
3663  // Type::FunctionTypeBitfields::ExtInfo as well.
3664 
3665  // | CC |noreturn|produces|nocallersavedregs|regparm|nocfcheck|cmsenscall|
3666  // |0 .. 4| 5 | 6 | 7 |8 .. 10| 11 | 12 |
3667  //
3668  // regparm is either 0 (no regparm attribute) or the regparm value+1.
3669  enum { CallConvMask = 0x1F };
3670  enum { NoReturnMask = 0x20 };
3671  enum { ProducesResultMask = 0x40 };
3672  enum { NoCallerSavedRegsMask = 0x80 };
3673  enum {
3674  RegParmMask = 0x700,
3675  RegParmOffset = 8
3676  };
3677  enum { NoCfCheckMask = 0x800 };
3678  enum { CmseNSCallMask = 0x1000 };
3679  uint16_t Bits = CC_C;
3680 
3681  ExtInfo(unsigned Bits) : Bits(static_cast<uint16_t>(Bits)) {}
3682 
3683  public:
3684  // Constructor with no defaults. Use this when you know that you
3685  // have all the elements (when reading an AST file for example).
3686  ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
3687  bool producesResult, bool noCallerSavedRegs, bool NoCfCheck,
3688  bool cmseNSCall) {
3689  assert((!hasRegParm || regParm < 7) && "Invalid regparm value");
3690  Bits = ((unsigned)cc) | (noReturn ? NoReturnMask : 0) |
3691  (producesResult ? ProducesResultMask : 0) |
3692  (noCallerSavedRegs ? NoCallerSavedRegsMask : 0) |
3693  (hasRegParm ? ((regParm + 1) << RegParmOffset) : 0) |
3694  (NoCfCheck ? NoCfCheckMask : 0) |
3695  (cmseNSCall ? CmseNSCallMask : 0);
3696  }
3697 
3698  // Constructor with all defaults. Use when for example creating a
3699  // function known to use defaults.
3700  ExtInfo() = default;
3701 
3702  // Constructor with just the calling convention, which is an important part
3703  // of the canonical type.
3704  ExtInfo(CallingConv CC) : Bits(CC) {}
3705 
3706  bool getNoReturn() const { return Bits & NoReturnMask; }
3707  bool getProducesResult() const { return Bits & ProducesResultMask; }
3708  bool getCmseNSCall() const { return Bits & CmseNSCallMask; }
3709  bool getNoCallerSavedRegs() const { return Bits & NoCallerSavedRegsMask; }
3710  bool getNoCfCheck() const { return Bits & NoCfCheckMask; }
3711  bool getHasRegParm() const { return ((Bits & RegParmMask) >> RegParmOffset) != 0; }
3712 
3713  unsigned getRegParm() const {
3714  unsigned RegParm = (Bits & RegParmMask) >> RegParmOffset;
3715  if (RegParm > 0)
3716  --RegParm;
3717  return RegParm;
3718  }
3719 
3720  CallingConv getCC() const { return CallingConv(Bits & CallConvMask); }
3721 
3722  bool operator==(ExtInfo Other) const {
3723  return Bits == Other.Bits;
3724  }
3725  bool operator!=(ExtInfo Other) const {
3726  return Bits != Other.Bits;
3727  }
3728 
3729  // Note that we don't have setters. That is by design, use
3730  // the following with methods instead of mutating these objects.
3731 
3732  ExtInfo withNoReturn(bool noReturn) const {
3733  if (noReturn)
3734  return ExtInfo(Bits | NoReturnMask);
3735  else
3736  return ExtInfo(Bits & ~NoReturnMask);
3737  }
3738 
3739  ExtInfo withProducesResult(bool producesResult) const {
3740  if (producesResult)
3741  return ExtInfo(Bits | ProducesResultMask);
3742  else
3743  return ExtInfo(Bits & ~ProducesResultMask);
3744  }
3745 
3746  ExtInfo withCmseNSCall(bool cmseNSCall) const {
3747  if (cmseNSCall)
3748  return ExtInfo(Bits | CmseNSCallMask);
3749  else
3750  return ExtInfo(Bits & ~CmseNSCallMask);
3751  }
3752 
3753  ExtInfo withNoCallerSavedRegs(bool noCallerSavedRegs) const {
3754  if (noCallerSavedRegs)
3755  return ExtInfo(Bits | NoCallerSavedRegsMask);
3756  else
3757  return ExtInfo(Bits & ~NoCallerSavedRegsMask);
3758  }
3759 
3760  ExtInfo withNoCfCheck(bool noCfCheck) const {
3761  if (noCfCheck)
3762  return ExtInfo(Bits | NoCfCheckMask);
3763  else
3764  return ExtInfo(Bits & ~NoCfCheckMask);
3765  }
3766 
3767  ExtInfo withRegParm(unsigned RegParm) const {
3768  assert(RegParm < 7 && "Invalid regparm value");
3769  return ExtInfo((Bits & ~RegParmMask) |
3770  ((RegParm + 1) << RegParmOffset));
3771  }
3772 
3774  return ExtInfo((Bits & ~CallConvMask) | (unsigned) cc);
3775  }
3776 
3777  void Profile(llvm::FoldingSetNodeID &ID) const {
3778  ID.AddInteger(Bits);
3779  }
3780  };
3781 
3782  /// A simple holder for a QualType representing a type in an
3783  /// exception specification. Unfortunately needed by FunctionProtoType
3784  /// because TrailingObjects cannot handle repeated types.
3786 
3787  /// A simple holder for various uncommon bits which do not fit in
3788  /// FunctionTypeBitfields. Aligned to alignof(void *) to maintain the
3789  /// alignment of subsequent objects in TrailingObjects. You must update
3790  /// hasExtraBitfields in FunctionProtoType after adding extra data here.
3791  struct alignas(void *) FunctionTypeExtraBitfields {
3792  /// The number of types in the exception specification.
3793  /// A whole unsigned is not needed here and according to
3794  /// [implimits] 8 bits would be enough here.
3796  };
3797 
3798 protected:
3801  : Type(tc, Canonical, Dependence), ResultType(res) {
3802  FunctionTypeBits.ExtInfo = Info.Bits;
3803  }
3804 
3806  return Qualifiers::fromFastMask(FunctionTypeBits.FastTypeQuals);
3807  }
3808 
3809 public:
3810  QualType getReturnType() const { return ResultType; }
3811 
3812  bool getHasRegParm() const { return getExtInfo().getHasRegParm(); }
3813  unsigned getRegParmType() const { return getExtInfo().getRegParm(); }
3814 
3815  /// Determine whether this function type includes the GNU noreturn
3816  /// attribute. The C++11 [[noreturn]] attribute does not affect the function
3817  /// type.
3818  bool getNoReturnAttr() const { return getExtInfo().getNoReturn(); }
3819 
3820  bool getCmseNSCallAttr() const { return getExtInfo().getCmseNSCall(); }
3821  CallingConv getCallConv() const { return getExtInfo().getCC(); }
3822  ExtInfo getExtInfo() const { return ExtInfo(FunctionTypeBits.ExtInfo); }
3823 
3824  static_assert((~Qualifiers::FastMask & Qualifiers::CVRMask) == 0,
3825  "Const, volatile and restrict are assumed to be a subset of "
3826  "the fast qualifiers.");
3827 
3828  bool isConst() const { return getFastTypeQuals().hasConst(); }
3829  bool isVolatile() const { return getFastTypeQuals().hasVolatile(); }
3830  bool isRestrict() const { return getFastTypeQuals().hasRestrict(); }
3831 
3832  /// Determine the type of an expression that calls a function of
3833  /// this type.
3834  QualType getCallResultType(const ASTContext &Context) const {
3835  return getReturnType().getNonLValueExprType(Context);
3836  }
3837 
3838  static StringRef getNameForCallConv(CallingConv CC);
3839 
3840  static bool classof(const Type *T) {
3841  return T->getTypeClass() == FunctionNoProto ||
3842  T->getTypeClass() == FunctionProto;
3843  }
3844 };
3845 
3846 /// Represents a K&R-style 'int foo()' function, which has
3847 /// no information available about its arguments.
3848 class FunctionNoProtoType : public FunctionType, public llvm::FoldingSetNode {
3849  friend class ASTContext; // ASTContext creates these.
3850 
3851  FunctionNoProtoType(QualType Result, QualType Canonical, ExtInfo Info)
3852  : FunctionType(FunctionNoProto, Result, Canonical,
3853  Result->getDependence() &
3854  ~(TypeDependence::DependentInstantiation |
3855  TypeDependence::UnexpandedPack),
3856  Info) {}
3857 
3858 public:
3859  // No additional state past what FunctionType provides.
3860 
3861  bool isSugared() const { return false; }
3862  QualType desugar() const { return QualType(this, 0); }
3863 
3864  void Profile(llvm::FoldingSetNodeID &ID) {
3866  }
3867 
3868  static void Profile(llvm::FoldingSetNodeID &ID, QualType ResultType,
3869  ExtInfo Info) {
3870  Info.Profile(ID);
3871  ID.AddPointer(ResultType.getAsOpaquePtr());
3872  }
3873 
3874  static bool classof(const Type *T) {
3875  return T->getTypeClass() == FunctionNoProto;
3876  }
3877 };
3878 
3879 /// Represents a prototype with parameter type info, e.g.
3880 /// 'int foo(int)' or 'int foo(void)'. 'void' is represented as having no
3881 /// parameters, not as having a single void parameter. Such a type can have
3882 /// an exception specification, but this specification is not part of the
3883 /// canonical type. FunctionProtoType has several trailing objects, some of
3884 /// which optional. For more information about the trailing objects see
3885 /// the first comment inside FunctionProtoType.
3887  : public FunctionType,
3888  public llvm::FoldingSetNode,
3889  private llvm::TrailingObjects<
3890  FunctionProtoType, QualType, SourceLocation,
3891  FunctionType::FunctionTypeExtraBitfields, FunctionType::ExceptionType,
3892  Expr *, FunctionDecl *, FunctionType::ExtParameterInfo, Qualifiers> {
3893  friend class ASTContext; // ASTContext creates these.
3894  friend TrailingObjects;
3895 
3896  // FunctionProtoType is followed by several trailing objects, some of
3897  // which optional. They are in order:
3898  //
3899  // * An array of getNumParams() QualType holding the parameter types.
3900  // Always present. Note that for the vast majority of FunctionProtoType,
3901  // these will be the only trailing objects.
3902  //
3903  // * Optionally if the function is variadic, the SourceLocation of the
3904  // ellipsis.
3905  //
3906  // * Optionally if some extra data is stored in FunctionTypeExtraBitfields
3907  // (see FunctionTypeExtraBitfields and FunctionTypeBitfields):
3908  // a single FunctionTypeExtraBitfields. Present if and only if
3909  // hasExtraBitfields() is true.
3910  //
3911  // * Optionally exactly one of:
3912  // * an array of getNumExceptions() ExceptionType,
3913  // * a single Expr *,
3914  // * a pair of FunctionDecl *,
3915  // * a single FunctionDecl *
3916  // used to store information about the various types of exception
3917  // specification. See getExceptionSpecSize for the details.
3918  //
3919  // * Optionally an array of getNumParams() ExtParameterInfo holding
3920  // an ExtParameterInfo for each of the parameters. Present if and
3921  // only if hasExtParameterInfos() is true.
3922  //
3923  // * Optionally a Qualifiers object to represent extra qualifiers that can't
3924  // be represented by FunctionTypeBitfields.FastTypeQuals. Present if and only
3925  // if hasExtQualifiers() is true.
3926  //
3927  // The optional FunctionTypeExtraBitfields has to be before the data
3928  // related to the exception specification since it contains the number
3929  // of exception types.
3930  //
3931  // We put the ExtParameterInfos last. If all were equal, it would make
3932  // more sense to put these before the exception specification, because
3933  // it's much easier to skip past them compared to the elaborate switch
3934  // required to skip the exception specification. However, all is not
3935  // equal; ExtParameterInfos are used to model very uncommon features,
3936  // and it's better not to burden the more common paths.
3937 
3938 public:
3939  /// Holds information about the various types of exception specification.
3940  /// ExceptionSpecInfo is not stored as such in FunctionProtoType but is
3941  /// used to group together the various bits of information about the
3942  /// exception specification.
3944  /// The kind of exception specification this is.
3946 
3947  /// Explicitly-specified list of exception types.
3949 
3950  /// Noexcept expression, if this is a computed noexcept specification.
3951  Expr *NoexceptExpr = nullptr;
3952 
3953  /// The function whose exception specification this is, for
3954  /// EST_Unevaluated and EST_Uninstantiated.
3956 
3957  /// The function template whose exception specification this is instantiated
3958  /// from, for EST_Uninstantiated.
3960 
3961  ExceptionSpecInfo() = default;
3962 
3964  };
3965 
3966  /// Extra information about a function prototype. ExtProtoInfo is not
3967  /// stored as such in FunctionProtoType but is used to group together
3968  /// the various bits of extra information about a function prototype.
3969  struct ExtProtoInfo {
3971  bool Variadic : 1;
3978 
3980 
3983 
3985  ExtProtoInfo Result(*this);
3986  Result.ExceptionSpec = ESI;
3987  return Result;
3988  }
3989  };
3990 
3991 private:
3992  unsigned numTrailingObjects(OverloadToken<QualType>) const {
3993  return getNumParams();
3994  }
3995 
3996  unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
3997  return isVariadic();
3998  }
3999 
4000  unsigned numTrailingObjects(OverloadToken<FunctionTypeExtraBitfields>) const {
4001  return hasExtraBitfields();
4002  }
4003 
4004  unsigned numTrailingObjects(OverloadToken<ExceptionType>) const {
4005  return getExceptionSpecSize().NumExceptionType;
4006  }
4007 
4008  unsigned numTrailingObjects(OverloadToken<Expr *>) const {
4009  return getExceptionSpecSize().NumExprPtr;
4010  }
4011 
4012  unsigned numTrailingObjects(OverloadToken<FunctionDecl *>) const {
4013  return getExceptionSpecSize().NumFunctionDeclPtr;
4014  }
4015 
4016  unsigned numTrailingObjects(OverloadToken<ExtParameterInfo>) const {
4017  return hasExtParameterInfos() ? getNumParams() : 0;
4018  }
4019 
4020  /// Determine whether there are any argument types that
4021  /// contain an unexpanded parameter pack.
4022  static bool containsAnyUnexpandedParameterPack(const QualType *ArgArray,
4023  unsigned numArgs) {
4024  for (unsigned Idx = 0; Idx < numArgs; ++Idx)
4025  if (ArgArray[Idx]->containsUnexpandedParameterPack())
4026  return true;
4027 
4028  return false;
4029  }
4030 
4031  FunctionProtoType(QualType result, ArrayRef<QualType> params,
4032  QualType canonical, const ExtProtoInfo &epi);
4033 
4034  /// This struct is returned by getExceptionSpecSize and is used to
4035  /// translate an ExceptionSpecificationType to the number and kind
4036  /// of trailing objects related to the exception specification.
4037  struct ExceptionSpecSizeHolder {
4038  unsigned NumExceptionType;
4039  unsigned NumExprPtr;
4040  unsigned NumFunctionDeclPtr;
4041  };
4042 
4043  /// Return the number and kind of trailing objects
4044  /// related to the exception specification.
4045  static ExceptionSpecSizeHolder
4046  getExceptionSpecSize(ExceptionSpecificationType EST, unsigned NumExceptions) {
4047  switch (EST) {
4048  case EST_None:
4049  case EST_DynamicNone:
4050  case EST_MSAny:
4051  case EST_BasicNoexcept:
4052  case EST_Unparsed:
4053  case EST_NoThrow:
4054  return {0, 0, 0};
4055 
4056  case EST_Dynamic:
4057  return {NumExceptions, 0, 0};
4058 
4059  case EST_DependentNoexcept:
4060  case EST_NoexceptFalse:
4061  case EST_NoexceptTrue:
4062  return {0, 1, 0};
4063 
4064  case EST_Uninstantiated:
4065  return {0, 0, 2};
4066 
4067  case EST_Unevaluated:
4068  return {0, 0, 1};
4069  }
4070  llvm_unreachable("bad exception specification kind");
4071  }
4072 
4073  /// Return the number and kind of trailing objects
4074  /// related to the exception specification.
4075  ExceptionSpecSizeHolder getExceptionSpecSize() const {
4076  return getExceptionSpecSize(getExceptionSpecType(), getNumExceptions());
4077  }
4078 
4079  /// Whether the trailing FunctionTypeExtraBitfields is present.
4080  static bool hasExtraBitfields(ExceptionSpecificationType EST) {
4081  // If the exception spec type is EST_Dynamic then we have > 0 exception
4082  // types and the exact number is stored in FunctionTypeExtraBitfields.
4083  return EST == EST_Dynamic;
4084  }
4085 
4086  /// Whether the trailing FunctionTypeExtraBitfields is present.
4087  bool hasExtraBitfields() const {
4088  return hasExtraBitfields(getExceptionSpecType());
4089  }
4090 
4091  bool hasExtQualifiers() const {
4092  return FunctionTypeBits.HasExtQuals;
4093  }
4094 
4095 public:
4096  unsigned getNumParams() const { return FunctionTypeBits.NumParams; }
4097 
4098  QualType getParamType(unsigned i) const {
4099  assert(i < getNumParams() && "invalid parameter index");
4100  return param_type_begin()[i];
4101  }
4102 
4104  return llvm::makeArrayRef(param_type_begin(), param_type_end());
4105  }
4106 
4108  ExtProtoInfo EPI;
4109  EPI.ExtInfo = getExtInfo();
4110  EPI.Variadic = isVariadic();
4111  EPI.EllipsisLoc = getEllipsisLoc();
4114  EPI.TypeQuals = getMethodQuals();
4115  EPI.RefQualifier = getRefQualifier();
4117  return EPI;
4118  }
4119 
4120  /// Get the kind of exception specification on this function.
4122  return static_cast<ExceptionSpecificationType>(
4123  FunctionTypeBits.ExceptionSpecType);
4124  }
4125 
4126  /// Return whether this function has any kind of exception spec.
4127  bool hasExceptionSpec() const { return getExceptionSpecType() != EST_None; }
4128 
4129  /// Return whether this function has a dynamic (throw) exception spec.
4132  }
4133 
4134  /// Return whether this function has a noexcept exception spec.
4137  }
4138 
4139  /// Return whether this function has a dependent exception spec.
4140  bool hasDependentExceptionSpec() const;
4141 
4142  /// Return whether this function has an instantiation-dependent exception
4143  /// spec.
4145 
4146  /// Return all the available information about this type's exception spec.
4148  ExceptionSpecInfo Result;
4149  Result.Type = getExceptionSpecType();
4150  if (Result.Type == EST_Dynamic) {
4151  Result.Exceptions = exceptions();
4152  } else if (isComputedNoexcept(Result.Type)) {
4153  Result.NoexceptExpr = getNoexceptExpr();
4154  } else if (Result.Type == EST_Uninstantiated) {
4155  Result.SourceDecl = getExceptionSpecDecl();
4156  Result.SourceTemplate = getExceptionSpecTemplate();
4157  } else if (Result.Type == EST_Unevaluated) {
4158  Result.SourceDecl = getExceptionSpecDecl();
4159  }
4160  return Result;
4161  }
4162 
4163  /// Return the number of types in the exception specification.
4164  unsigned getNumExceptions() const {
4165  return getExceptionSpecType() == EST_Dynamic
4166  ? getTrailingObjects<FunctionTypeExtraBitfields>()
4167  ->NumExceptionType
4168  : 0;
4169  }
4170 
4171  /// Return the ith exception type, where 0 <= i < getNumExceptions().
4172  QualType getExceptionType(unsigned i) const {
4173  assert(i < getNumExceptions() && "Invalid exception number!");
4174  return exception_begin()[i];
4175  }
4176 
4177  /// Return the expression inside noexcept(expression), or a null pointer
4178  /// if there is none (because the exception spec is not of this form).
4181  return nullptr;
4182  return *getTrailingObjects<Expr *>();
4183  }
4184 
4185  /// If this function type has an exception specification which hasn't
4186  /// been determined yet (either because it has not been evaluated or because
4187  /// it has not been instantiated), this is the function whose exception
4188  /// specification is represented by this type.
4192  return nullptr;
4193  return getTrailingObjects<FunctionDecl *>()[0];
4194  }
4195 
4196  /// If this function type has an uninstantiated exception
4197  /// specification, this is the function whose exception specification
4198  /// should be instantiated to find the exception specification for
4199  /// this type.
4202  return nullptr;
4203  return getTrailingObjects<FunctionDecl *>()[1];
4204  }
4205 
4206  /// Determine whether this function type has a non-throwing exception
4207  /// specification.
4208  CanThrowResult canThrow() const;
4209 
4210  /// Determine whether this function type has a non-throwing exception
4211  /// specification. If this depends on template arguments, returns
4212  /// \c ResultIfDependent.
4213  bool isNothrow(bool ResultIfDependent = false) const {
4214  return ResultIfDependent ? canThrow() != CT_Can : canThrow() == CT_Cannot;
4215  }
4216 
4217  /// Whether this function prototype is variadic.
4218  bool isVariadic() const { return FunctionTypeBits.Variadic; }
4219 
4221  return isVariadic() ? *getTrailingObjects<SourceLocation>()
4222  : SourceLocation();
4223  }
4224 
4225  /// Determines whether this function prototype contains a
4226  /// parameter pack at the end.
4227  ///
4228  /// A function template whose last parameter is a parameter pack can be
4229  /// called with an arbitrary number of arguments, much like a variadic
4230  /// function.
4231  bool isTemplateVariadic() const;
4232 
4233  /// Whether this function prototype has a trailing return type.
4234  bool hasTrailingReturn() const { return FunctionTypeBits.HasTrailingReturn; }
4235 
4237  if (hasExtQualifiers())
4238  return *getTrailingObjects<Qualifiers>();
4239  else
4240  return getFastTypeQuals();
4241  }
4242 
4243  /// Retrieve the ref-qualifier associated with this function type.
4245  return static_cast<RefQualifierKind>(FunctionTypeBits.RefQualifier);
4246  }
4247 
4249  using param_type_range = llvm::iterator_range<param_type_iterator>;
4250 
4253  }
4254 
4256  return getTrailingObjects<QualType>();
4257  }
4258 
4260  return param_type_begin() + getNumParams();
4261  }
4262 
4263  using exception_iterator = const QualType *;
4264 
4266  return llvm::makeArrayRef(exception_begin(), exception_end());
4267  }
4268 
4270  return reinterpret_cast<exception_iterator>(
4271  getTrailingObjects<ExceptionType>());
4272  }
4273 
4275  return exception_begin() + getNumExceptions();
4276  }
4277 
4278  /// Is there any interesting extra information for any of the parameters
4279  /// of this function type?
4280  bool hasExtParameterInfos() const {
4281  return FunctionTypeBits.HasExtParameterInfos;
4282  }
4283 
4285  assert(hasExtParameterInfos());
4286  return ArrayRef<ExtParameterInfo>(getTrailingObjects<ExtParameterInfo>(),
4287  getNumParams());
4288  }
4289 
4290  /// Return a pointer to the beginning of the array of extra parameter
4291  /// information, if present, or else null if none of the parameters
4292  /// carry it. This is equivalent to getExtProtoInfo().ExtParameterInfos.
4294  if (!hasExtParameterInfos())
4295  return nullptr;
4296  return getTrailingObjects<ExtParameterInfo>();
4297  }
4298 
4300  assert(I < getNumParams() && "parameter index out of range");
4301  if (hasExtParameterInfos())
4302  return getTrailingObjects<ExtParameterInfo>()[I];
4303  return ExtParameterInfo();
4304  }
4305 
4306  ParameterABI getParameterABI(unsigned I) const {
4307  assert(I < getNumParams() && "parameter index out of range");
4308  if (hasExtParameterInfos())
4309  return getTrailingObjects<ExtParameterInfo>()[I].getABI();
4310  return ParameterABI::Ordinary;
4311  }
4312 
4313  bool isParamConsumed(unsigned I) const {
4314  assert(I < getNumParams() && "parameter index out of range");
4315  if (hasExtParameterInfos())
4316  return getTrailingObjects<ExtParameterInfo>()[I].isConsumed();
4317  return false;
4318  }
4319 
4320  bool isSugared() const { return false; }
4321  QualType desugar() const { return QualType(this, 0); }
4322 
4323  void printExceptionSpecification(raw_ostream &OS,
4324  const PrintingPolicy &Policy) const;
4325 
4326  static bool classof(const Type *T) {
4327  return T->getTypeClass() == FunctionProto;
4328  }
4329 
4330  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx);
4331  static void Profile(llvm::FoldingSetNodeID &ID, QualType Result,
4332  param_type_iterator ArgTys, unsigned NumArgs,
4333  const ExtProtoInfo &EPI, const ASTContext &Context,
4334  bool Canonical);
4335 };
4336 
4337 /// Represents the dependent type named by a dependently-scoped
4338 /// typename using declaration, e.g.
4339 /// using typename Base<T>::foo;
4340 ///
4341 /// Template instantiation turns these into the underlying type.
4342 class UnresolvedUsingType : public Type {
4343  friend class ASTContext; // ASTContext creates these.
4344 
4346 
4348  : Type(UnresolvedUsing, QualType(),
4349  TypeDependence::DependentInstantiation),
4350  Decl(const_cast<UnresolvedUsingTypenameDecl *>(D)) {}
4351 
4352 public:
4354 
4355  bool isSugared() const { return false; }
4356  QualType desugar() const { return QualType(this, 0); }
4357 
4358  static bool classof(const Type *T) {
4359  return T->getTypeClass() == UnresolvedUsing;
4360  }
4361 
4362  void Profile(llvm::FoldingSetNodeID &ID) {
4363  return Profile(ID, Decl);
4364  }
4365 
4366  static void Profile(llvm::FoldingSetNodeID &ID,
4368  ID.AddPointer(D);
4369  }
4370 };
4371 
4372 class UsingType : public Type, public llvm::FoldingSetNode {
4373  UsingShadowDecl *Found;
4374  friend class ASTContext; // ASTContext creates these.
4375 
4376  UsingType(const UsingShadowDecl *Found, QualType Underlying, QualType Canon);
4377 
4378 public:
4379  UsingShadowDecl *getFoundDecl() const { return Found; }
4380  QualType getUnderlyingType() const;
4381 
4382  bool isSugared() const { return true; }
4383  QualType desugar() const { return getUnderlyingType(); }
4384 
4385  void Profile(llvm::FoldingSetNodeID &ID) { Profile(ID, Found); }
4386  static void Profile(llvm::FoldingSetNodeID &ID,
4387  const UsingShadowDecl *Found) {
4388  ID.AddPointer(Found);
4389  }
4390  static bool classof(const Type *T) { return T->getTypeClass() == Using; }
4391 };
4392 
4393 class TypedefType : public Type {
4395 
4396 private:
4397  friend class ASTContext; // ASTContext creates these.
4398 
4399  TypedefType(TypeClass tc, const TypedefNameDecl *D, QualType underlying,
4400  QualType can);
4401 
4402 public:
4403  TypedefNameDecl *getDecl() const { return Decl; }
4404 
4405  bool isSugared() const { return true; }
4406  QualType desugar() const;
4407 
4408  static bool classof(const Type *T) { return T->getTypeClass() == Typedef; }
4409 };
4410 
4411 /// Sugar type that represents a type that was qualified by a qualifier written
4412 /// as a macro invocation.
4413 class MacroQualifiedType : public Type {
4414  friend class ASTContext; // ASTContext creates these.
4415 
4416  QualType UnderlyingTy;
4417  const IdentifierInfo *MacroII;
4418 
4419  MacroQualifiedType(QualType UnderlyingTy, QualType CanonTy,
4420  const IdentifierInfo *MacroII)
4421  : Type(MacroQualified, CanonTy, UnderlyingTy->getDependence()),
4422  UnderlyingTy(UnderlyingTy), MacroII(MacroII) {
4423  assert(isa<AttributedType>(UnderlyingTy) &&
4424  "Expected a macro qualified type to only wrap attributed types.");
4425  }
4426 
4427 public:
4428  const IdentifierInfo *getMacroIdentifier() const { return MacroII; }
4429  QualType getUnderlyingType() const { return UnderlyingTy; }
4430 
4431  /// Return this attributed type's modified type with no qualifiers attached to
4432  /// it.
4433  QualType getModifiedType() const;
4434 
4435  bool isSugared() const { return true; }
4436  QualType desugar() const;
4437 
4438  static bool classof(const Type *T) {
4439  return T->getTypeClass() == MacroQualified;
4440  }
4441 };
4442 
4443 /// Represents a `typeof` (or __typeof__) expression (a GCC extension).
4444 class TypeOfExprType : public Type {
4445  Expr *TOExpr;
4446 
4447 protected:
4448  friend class ASTContext; // ASTContext creates these.
4449 
4450  TypeOfExprType(Expr *E, QualType can = QualType());
4451 
4452 public:
4453  Expr *getUnderlyingExpr() const { return TOExpr; }
4454 
4455  /// Remove a single level of sugar.
4456  QualType desugar() const;
4457 
4458  /// Returns whether this type directly provides sugar.
4459  bool isSugared() const;
4460 
4461  static bool classof(const Type *T) { return T->getTypeClass() == TypeOfExpr; }
4462 };
4463 
4464 /// Internal representation of canonical, dependent
4465 /// `typeof(expr)` types.
4466 ///
4467 /// This class is used internally by the ASTContext to manage
4468 /// canonical, dependent types, only. Clients will only see instances
4469 /// of this class via TypeOfExprType nodes.
4471  : public TypeOfExprType, public llvm::FoldingSetNode {
4472  const ASTContext &Context;
4473 
4474 public:
4476  : TypeOfExprType(E), Context(Context) {}
4477 
4478  void Profile(llvm::FoldingSetNodeID &ID) {
4479  Profile(ID, Context, getUnderlyingExpr());
4480  }
4481 
4482  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
4483  Expr *E);
4484 };
4485 
4486 /// Represents `typeof(type)`, a GCC extension.
4487 class TypeOfType : public Type {
4488  friend class ASTContext; // ASTContext creates these.
4489 
4490  QualType TOType;
4491 
4492  TypeOfType(QualType T, QualType can)
4493  : Type(TypeOf, can, T->getDependence()), TOType(T) {
4494  assert(!isa<TypedefType>(can) && "Invalid canonical type");
4495  }
4496 
4497 public:
4498  QualType getUnderlyingType() const { return TOType; }
4499 
4500  /// Remove a single level of sugar.
4501  QualType desugar() const { return getUnderlyingType(); }
4502 
4503  /// Returns whether this type directly provides sugar.
4504  bool isSugared() const { return true; }
4505 
4506  static bool classof(const Type *T) { return T->getTypeClass() == TypeOf; }
4507 };
4508 
4509 /// Represents the type `decltype(expr)` (C++11).
4510 class DecltypeType : public Type {
4511  Expr *E;
4512  QualType UnderlyingType;
4513 
4514 protected:
4515  friend class ASTContext; // ASTContext creates these.
4516 
4517  DecltypeType(Expr *E, QualType underlyingType, QualType can = QualType());
4518 
4519 public:
4520  Expr *getUnderlyingExpr() const { return E; }
4521  QualType getUnderlyingType() const { return UnderlyingType; }
4522 
4523  /// Remove a single level of sugar.
4524  QualType desugar() const;
4525 
4526  /// Returns whether this type directly provides sugar.
4527  bool isSugared() const;
4528 
4529  static bool classof(const Type *T) { return T->getTypeClass() == Decltype; }
4530 };
4531 
4532 /// Internal representation of canonical, dependent
4533 /// decltype(expr) types.
4534 ///
4535 /// This class is used internally by the ASTContext to manage
4536 /// canonical, dependent types, only. Clients will only see instances
4537 /// of this class via DecltypeType nodes.
4538 class DependentDecltypeType : public DecltypeType, public llvm::FoldingSetNode {
4539  const ASTContext &Context;
4540 
4541 public:
4542  DependentDecltypeType(const ASTContext &Context, Expr *E);
4543 
4544  void Profile(llvm::FoldingSetNodeID &ID) {
4545  Profile(ID, Context, getUnderlyingExpr());
4546  }
4547 
4548  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
4549  Expr *E);
4550 };
4551 
4552 /// A unary type transform, which is a type constructed from another.
4553 class UnaryTransformType : public Type {
4554 public:
4555  enum UTTKind {
4557  };
4558 
4559 private:
4560  /// The untransformed type.
4561  QualType BaseType;
4562 
4563  /// The transformed type if not dependent, otherwise the same as BaseType.
4564  QualType UnderlyingType;
4565 
4566  UTTKind UKind;
4567 
4568 protected:
4569  friend class ASTContext;
4570 
4571  UnaryTransformType(QualType BaseTy, QualType UnderlyingTy, UTTKind UKind,
4572  QualType CanonicalTy);
4573 
4574 public:
4575  bool isSugared() const { return !isDependentType(); }
4576  QualType desugar() const { return UnderlyingType; }
4577 
4578  QualType getUnderlyingType() const { return UnderlyingType; }
4579  QualType getBaseType() const { return BaseType; }
4580 
4581  UTTKind getUTTKind() const { return UKind; }
4582 
4583  static bool classof(const Type *T) {
4584  return T->getTypeClass() == UnaryTransform;
4585  }
4586 };
4587 
4588 /// Internal representation of canonical, dependent
4589 /// __underlying_type(type) types.
4590 ///
4591 /// This class is used internally by the ASTContext to manage
4592 /// canonical, dependent types, only. Clients will only see instances
4593 /// of this class via UnaryTransformType nodes.
4595  public llvm::FoldingSetNode {
4596 public:
4597  DependentUnaryTransformType(const ASTContext &C, QualType BaseType,
4598  UTTKind UKind);
4599 
4600  void Profile(llvm::FoldingSetNodeID &ID) {
4602  }
4603 
4604  static void Profile(llvm::FoldingSetNodeID &ID, QualType BaseType,
4605  UTTKind UKind) {
4606  ID.AddPointer(BaseType.getAsOpaquePtr());
4607  ID.AddInteger((unsigned)UKind);
4608  }
4609 };
4610 
4611 class TagType : public Type {
4612  friend class ASTReader;
4613  template <class T> friend class serialization::AbstractTypeReader;
4614 
4615  /// Stores the TagDecl associated with this type. The decl may point to any
4616  /// TagDecl that declares the entity.
4617  TagDecl *decl;
4618 
4619 protected:
4620  TagType(TypeClass TC, const TagDecl *D, QualType can);
4621 
4622 public:
4623  TagDecl *getDecl() const;
4624 
4625  /// Determines whether this type is in the process of being defined.
4626  bool isBeingDefined() const;
4627 
4628  static bool classof(const Type *T) {
4629  return T->getTypeClass() == Enum || T->getTypeClass() == Record;
4630  }
4631 };
4632 
4633 /// A helper class that allows the use of isa/cast/dyncast
4634 /// to detect TagType objects of structs/unions/classes.
4635 class RecordType : public TagType {
4636 protected:
4637  friend class ASTContext; // ASTContext creates these.
4638 
4639  explicit RecordType(const RecordDecl *D)
4640  : TagType(Record, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4642  : TagType(TC, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4643 
4644 public:
4645  RecordDecl *getDecl() const {
4646  return reinterpret_cast<RecordDecl*>(TagType::getDecl());
4647  }
4648 
4649  /// Recursively check all fields in the record for const-ness. If any field
4650  /// is declared const, return true. Otherwise, return false.
4651  bool hasConstFields() const;
4652 
4653  bool isSugared() const { return false; }
4654  QualType desugar() const { return QualType(this, 0); }
4655 
4656  static bool classof(const Type *T) { return T->getTypeClass() == Record; }
4657 };
4658 
4659 /// A helper class that allows the use of isa/cast/dyncast
4660 /// to detect TagType objects of enums.
4661 class EnumType : public TagType {
4662  friend class ASTContext; // ASTContext creates these.
4663 
4664  explicit EnumType(const EnumDecl *D)
4665  : TagType(Enum, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4666 
4667 public:
4668  EnumDecl *getDecl() const {
4669  return reinterpret_cast<EnumDecl*>(TagType::getDecl());
4670  }
4671 
4672  bool isSugared() const { return false; }
4673  QualType desugar() const { return QualType(this, 0); }
4674 
4675  static bool classof(const Type *T) { return T->getTypeClass() == Enum; }
4676 };
4677 
4678 /// An attributed type is a type to which a type attribute has been applied.
4679 ///
4680 /// The "modified type" is the fully-sugared type to which the attributed
4681 /// type was applied; generally it is not canonically equivalent to the
4682 /// attributed type. The "equivalent type" is the minimally-desugared type
4683 /// which the type is canonically equivalent to.
4684 ///
4685 /// For example, in the following attributed type:
4686 /// int32_t __attribute__((vector_size(16)))
4687 /// - the modified type is the TypedefType for int32_t
4688 /// - the equivalent type is VectorType(16, int32_t)
4689 /// - the canonical type is VectorType(16, int)
4690 class AttributedType : public Type, public llvm::FoldingSetNode {
4691 public:
4692  using Kind = attr::Kind;
4693 
4694 private:
4695  friend class ASTContext; // ASTContext creates these
4696 
4697  QualType ModifiedType;
4698  QualType EquivalentType;
4699 
4700  AttributedType(QualType canon, attr::Kind attrKind, QualType modified,
4701  QualType equivalent)
4702  : Type(Attributed, canon, equivalent->getDependence()),
4703  ModifiedType(modified), EquivalentType(equivalent) {
4704  AttributedTypeBits.AttrKind = attrKind;
4705  }
4706 
4707 public:
4708  Kind getAttrKind() const {
4709  return static_cast<Kind>(AttributedTypeBits.AttrKind);
4710  }
4711 
4712  QualType getModifiedType() const { return ModifiedType; }
4713  QualType getEquivalentType() const { return EquivalentType; }
4714 
4715  bool isSugared() const { return true; }
4716  QualType desugar() const { return getEquivalentType(); }
4717 
4718  /// Does this attribute behave like a type qualifier?
4719  ///
4720  /// A type qualifier adjusts a type to provide specialized rules for
4721  /// a specific object, like the standard const and volatile qualifiers.
4722  /// This includes attributes controlling things like nullability,
4723  /// address spaces, and ARC ownership. The value of the object is still
4724  /// largely described by the modified type.
4725  ///
4726  /// In contrast, many type attributes "rewrite" their modified type to
4727  /// produce a fundamentally different type, not necessarily related in any
4728  /// formalizable way to the original type. For example, calling convention
4729  /// and vector attributes are not simple type qualifiers.
4730  ///
4731  /// Type qualifiers are often, but not always, reflected in the canonical
4732  /// type.
4733  bool isQualifier() const;
4734 
4735  bool isMSTypeSpec() const;
4736 
4737  bool isCallingConv() const;
4738 
4740 
4741  /// Retrieve the attribute kind corresponding to the given
4742  /// nullability kind.
4744  switch (kind) {
4746  return attr::TypeNonNull;
4747 
4749  return attr::TypeNullable;
4750 
4752  return attr::TypeNullableResult;
4753 
4755  return attr::TypeNullUnspecified;
4756  }
4757  llvm_unreachable("Unknown nullability kind.");
4758  }
4759 
4760  /// Strip off the top-level nullability annotation on the given
4761  /// type, if it's there.
4762  ///
4763  /// \param T The type to strip. If the type is exactly an
4764  /// AttributedType specifying nullability (without looking through
4765  /// type sugar), the nullability is returned and this type changed
4766  /// to the underlying modified type.
4767  ///
4768  /// \returns the top-level nullability, if present.
4770 
4771  void Profile(llvm::FoldingSetNodeID &ID) {
4772  Profile(ID, getAttrKind(), ModifiedType, EquivalentType);
4773  }
4774 
4775  static void Profile(llvm::FoldingSetNodeID &ID, Kind attrKind,
4776  QualType modified, QualType equivalent) {
4777  ID.AddInteger(attrKind);
4778  ID.AddPointer(modified.getAsOpaquePtr());
4779  ID.AddPointer(equivalent.getAsOpaquePtr());
4780  }
4781 
4782  static bool classof(const Type *T) {
4783  return T->getTypeClass() == Attributed;
4784  }
4785 };
4786 
4787 class TemplateTypeParmType : public Type, public llvm::FoldingSetNode {
4788  friend class ASTContext; // ASTContext creates these
4789 
4790  // Helper data collector for canonical types.
4791  struct CanonicalTTPTInfo {
4792  unsigned Depth : 15;
4793  unsigned ParameterPack : 1;
4794  unsigned Index : 16;
4795  };
4796 
4797  union {
4798  // Info for the canonical type.