clang  7.0.0svn
Type.h
Go to the documentation of this file.
1 //===- Type.h - C Language Family Type Representation -----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 /// \file
11 /// C Language Family Type Representation
12 ///
13 /// This file defines the clang::Type interface and subclasses, used to
14 /// represent types for languages in the C family.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #ifndef LLVM_CLANG_AST_TYPE_H
19 #define LLVM_CLANG_AST_TYPE_H
20 
22 #include "clang/AST/TemplateName.h"
24 #include "clang/Basic/Diagnostic.h"
26 #include "clang/Basic/LLVM.h"
27 #include "clang/Basic/Linkage.h"
30 #include "clang/Basic/Specifiers.h"
31 #include "clang/Basic/Visibility.h"
32 #include "llvm/ADT/APInt.h"
33 #include "llvm/ADT/ArrayRef.h"
34 #include "llvm/ADT/FoldingSet.h"
35 #include "llvm/ADT/None.h"
36 #include "llvm/ADT/Optional.h"
37 #include "llvm/ADT/PointerIntPair.h"
38 #include "llvm/ADT/PointerUnion.h"
39 #include "llvm/ADT/StringRef.h"
40 #include "llvm/ADT/Twine.h"
41 #include "llvm/ADT/iterator_range.h"
42 #include "llvm/Support/Casting.h"
43 #include "llvm/Support/Compiler.h"
44 #include "llvm/Support/ErrorHandling.h"
45 #include "llvm/Support/PointerLikeTypeTraits.h"
46 #include "llvm/Support/type_traits.h"
47 #include <cassert>
48 #include <cstddef>
49 #include <cstdint>
50 #include <cstring>
51 #include <string>
52 #include <type_traits>
53 #include <utility>
54 
55 namespace clang {
56 
57 class ExtQuals;
58 class QualType;
59 class TagDecl;
60 class Type;
61 
62 enum {
65 };
66 
67 } // namespace clang
68 
69 namespace llvm {
70 
71  template <typename T>
72  struct PointerLikeTypeTraits;
73  template<>
75  static inline void *getAsVoidPointer(::clang::Type *P) { return P; }
76 
78  return static_cast< ::clang::Type*>(P);
79  }
80 
81  enum { NumLowBitsAvailable = clang::TypeAlignmentInBits };
82  };
83 
84  template<>
86  static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }
87 
88  static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
89  return static_cast< ::clang::ExtQuals*>(P);
90  }
91 
92  enum { NumLowBitsAvailable = clang::TypeAlignmentInBits };
93  };
94 
95  template <>
96  struct isPodLike<clang::QualType> { static const bool value = true; };
97 
98 } // namespace llvm
99 
100 namespace clang {
101 
102 class ArrayType;
103 class ASTContext;
104 class AttributedType;
105 class AutoType;
106 class BuiltinType;
107 template <typename> class CanQual;
108 class ComplexType;
109 class CXXRecordDecl;
110 class DeclContext;
111 class DeducedType;
112 class EnumDecl;
113 class Expr;
114 class ExtQualsTypeCommonBase;
115 class FunctionDecl;
116 class FunctionNoProtoType;
117 class FunctionProtoType;
118 class IdentifierInfo;
119 class InjectedClassNameType;
120 class NamedDecl;
121 class ObjCInterfaceDecl;
122 class ObjCObjectPointerType;
123 class ObjCObjectType;
124 class ObjCProtocolDecl;
125 class ObjCTypeParamDecl;
126 class ParenType;
127 struct PrintingPolicy;
128 class RecordDecl;
129 class RecordType;
130 class Stmt;
131 class TagDecl;
132 class TemplateArgument;
133 class TemplateArgumentListInfo;
134 class TemplateArgumentLoc;
135 class TemplateSpecializationType;
136 class TemplateTypeParmDecl;
137 class TypedefNameDecl;
138 class TypedefType;
139 class UnresolvedUsingTypenameDecl;
140 
141 using CanQualType = CanQual<Type>;
142 
143  // Provide forward declarations for all of the *Type classes
144 #define TYPE(Class, Base) class Class##Type;
145 #include "clang/AST/TypeNodes.def"
146 
147 /// The collection of all-type qualifiers we support.
148 /// Clang supports five independent qualifiers:
149 /// * C99: const, volatile, and restrict
150 /// * MS: __unaligned
151 /// * Embedded C (TR18037): address spaces
152 /// * Objective C: the GC attributes (none, weak, or strong)
153 class Qualifiers {
154 public:
155  enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
156  Const = 0x1,
157  Restrict = 0x2,
158  Volatile = 0x4,
159  CVRMask = Const | Volatile | Restrict
160  };
161 
162  enum GC {
163  GCNone = 0,
165  Strong
166  };
167 
169  /// There is no lifetime qualification on this type.
171 
172  /// This object can be modified without requiring retains or
173  /// releases.
175 
176  /// Assigning into this object requires the old value to be
177  /// released and the new value to be retained. The timing of the
178  /// release of the old value is inexact: it may be moved to
179  /// immediately after the last known point where the value is
180  /// live.
182 
183  /// Reading or writing from this object requires a barrier call.
185 
186  /// Assigning into this object requires a lifetime extension.
187  OCL_Autoreleasing
188  };
189 
190  enum {
191  /// The maximum supported address space number.
192  /// 23 bits should be enough for anyone.
193  MaxAddressSpace = 0x7fffffu,
194 
195  /// The width of the "fast" qualifier mask.
196  FastWidth = 3,
197 
198  /// The fast qualifier mask.
199  FastMask = (1 << FastWidth) - 1
200  };
201 
202  /// Returns the common set of qualifiers while removing them from
203  /// the given sets.
205  // If both are only CVR-qualified, bit operations are sufficient.
206  if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
207  Qualifiers Q;
208  Q.Mask = L.Mask & R.Mask;
209  L.Mask &= ~Q.Mask;
210  R.Mask &= ~Q.Mask;
211  return Q;
212  }
213 
214  Qualifiers Q;
215  unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
216  Q.addCVRQualifiers(CommonCRV);
217  L.removeCVRQualifiers(CommonCRV);
218  R.removeCVRQualifiers(CommonCRV);
219 
220  if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
222  L.removeObjCGCAttr();
223  R.removeObjCGCAttr();
224  }
225 
226  if (L.getObjCLifetime() == R.getObjCLifetime()) {
228  L.removeObjCLifetime();
229  R.removeObjCLifetime();
230  }
231 
232  if (L.getAddressSpace() == R.getAddressSpace()) {
234  L.removeAddressSpace();
235  R.removeAddressSpace();
236  }
237  return Q;
238  }
239 
240  static Qualifiers fromFastMask(unsigned Mask) {
241  Qualifiers Qs;
242  Qs.addFastQualifiers(Mask);
243  return Qs;
244  }
245 
246  static Qualifiers fromCVRMask(unsigned CVR) {
247  Qualifiers Qs;
248  Qs.addCVRQualifiers(CVR);
249  return Qs;
250  }
251 
252  static Qualifiers fromCVRUMask(unsigned CVRU) {
253  Qualifiers Qs;
254  Qs.addCVRUQualifiers(CVRU);
255  return Qs;
256  }
257 
258  // Deserialize qualifiers from an opaque representation.
259  static Qualifiers fromOpaqueValue(unsigned opaque) {
260  Qualifiers Qs;
261  Qs.Mask = opaque;
262  return Qs;
263  }
264 
265  // Serialize these qualifiers into an opaque representation.
266  unsigned getAsOpaqueValue() const {
267  return Mask;
268  }
269 
270  bool hasConst() const { return Mask & Const; }
271  void setConst(bool flag) {
272  Mask = (Mask & ~Const) | (flag ? Const : 0);
273  }
274  void removeConst() { Mask &= ~Const; }
275  void addConst() { Mask |= Const; }
276 
277  bool hasVolatile() const { return Mask & Volatile; }
278  void setVolatile(bool flag) {
279  Mask = (Mask & ~Volatile) | (flag ? Volatile : 0);
280  }
281  void removeVolatile() { Mask &= ~Volatile; }
282  void addVolatile() { Mask |= Volatile; }
283 
284  bool hasRestrict() const { return Mask & Restrict; }
285  void setRestrict(bool flag) {
286  Mask = (Mask & ~Restrict) | (flag ? Restrict : 0);
287  }
288  void removeRestrict() { Mask &= ~Restrict; }
289  void addRestrict() { Mask |= Restrict; }
290 
291  bool hasCVRQualifiers() const { return getCVRQualifiers(); }
292  unsigned getCVRQualifiers() const { return Mask & CVRMask; }
293  void setCVRQualifiers(unsigned mask) {
294  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
295  Mask = (Mask & ~CVRMask) | mask;
296  }
297  void removeCVRQualifiers(unsigned mask) {
298  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
299  Mask &= ~mask;
300  }
302  removeCVRQualifiers(CVRMask);
303  }
304  void addCVRQualifiers(unsigned mask) {
305  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
306  Mask |= mask;
307  }
308  void addCVRUQualifiers(unsigned mask) {
309  assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits");
310  Mask |= mask;
311  }
312 
313  bool hasUnaligned() const { return Mask & UMask; }
314  void setUnaligned(bool flag) {
315  Mask = (Mask & ~UMask) | (flag ? UMask : 0);
316  }
317  void removeUnaligned() { Mask &= ~UMask; }
318  void addUnaligned() { Mask |= UMask; }
319 
320  bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
321  GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
323  Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
324  }
325  void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
327  assert(type);
328  setObjCGCAttr(type);
329  }
331  Qualifiers qs = *this;
332  qs.removeObjCGCAttr();
333  return qs;
334  }
336  Qualifiers qs = *this;
337  qs.removeObjCLifetime();
338  return qs;
339  }
340 
341  bool hasObjCLifetime() const { return Mask & LifetimeMask; }
343  return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
344  }
346  Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
347  }
348  void removeObjCLifetime() { setObjCLifetime(OCL_None); }
350  assert(type);
351  assert(!hasObjCLifetime());
352  Mask |= (type << LifetimeShift);
353  }
354 
355  /// True if the lifetime is neither None or ExplicitNone.
357  ObjCLifetime lifetime = getObjCLifetime();
358  return (lifetime > OCL_ExplicitNone);
359  }
360 
361  /// True if the lifetime is either strong or weak.
363  ObjCLifetime lifetime = getObjCLifetime();
364  return (lifetime == OCL_Strong || lifetime == OCL_Weak);
365  }
366 
367  bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
369  return static_cast<LangAS>(Mask >> AddressSpaceShift);
370  }
372  return isTargetAddressSpace(getAddressSpace());
373  }
374  /// Get the address space attribute value to be printed by diagnostics.
376  auto Addr = getAddressSpace();
377  // This function is not supposed to be used with language specific
378  // address spaces. If that happens, the diagnostic message should consider
379  // printing the QualType instead of the address space value.
380  assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace());
381  if (Addr != LangAS::Default)
382  return toTargetAddressSpace(Addr);
383  // TODO: The diagnostic messages where Addr may be 0 should be fixed
384  // since it cannot differentiate the situation where 0 denotes the default
385  // address space or user specified __attribute__((address_space(0))).
386  return 0;
387  }
388  void setAddressSpace(LangAS space) {
389  assert((unsigned)space <= MaxAddressSpace);
390  Mask = (Mask & ~AddressSpaceMask)
391  | (((uint32_t) space) << AddressSpaceShift);
392  }
393  void removeAddressSpace() { setAddressSpace(LangAS::Default); }
394  void addAddressSpace(LangAS space) {
395  assert(space != LangAS::Default);
396  setAddressSpace(space);
397  }
398 
399  // Fast qualifiers are those that can be allocated directly
400  // on a QualType object.
401  bool hasFastQualifiers() const { return getFastQualifiers(); }
402  unsigned getFastQualifiers() const { return Mask & FastMask; }
403  void setFastQualifiers(unsigned mask) {
404  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
405  Mask = (Mask & ~FastMask) | mask;
406  }
407  void removeFastQualifiers(unsigned mask) {
408  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
409  Mask &= ~mask;
410  }
412  removeFastQualifiers(FastMask);
413  }
414  void addFastQualifiers(unsigned mask) {
415  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits");
416  Mask |= mask;
417  }
418 
419  /// Return true if the set contains any qualifiers which require an ExtQuals
420  /// node to be allocated.
421  bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
423  Qualifiers Quals = *this;
424  Quals.setFastQualifiers(0);
425  return Quals;
426  }
427 
428  /// Return true if the set contains any qualifiers.
429  bool hasQualifiers() const { return Mask; }
430  bool empty() const { return !Mask; }
431 
432  /// Add the qualifiers from the given set to this set.
434  // If the other set doesn't have any non-boolean qualifiers, just
435  // bit-or it in.
436  if (!(Q.Mask & ~CVRMask))
437  Mask |= Q.Mask;
438  else {
439  Mask |= (Q.Mask & CVRMask);
440  if (Q.hasAddressSpace())
441  addAddressSpace(Q.getAddressSpace());
442  if (Q.hasObjCGCAttr())
443  addObjCGCAttr(Q.getObjCGCAttr());
444  if (Q.hasObjCLifetime())
445  addObjCLifetime(Q.getObjCLifetime());
446  }
447  }
448 
449  /// Remove the qualifiers from the given set from this set.
451  // If the other set doesn't have any non-boolean qualifiers, just
452  // bit-and the inverse in.
453  if (!(Q.Mask & ~CVRMask))
454  Mask &= ~Q.Mask;
455  else {
456  Mask &= ~(Q.Mask & CVRMask);
457  if (getObjCGCAttr() == Q.getObjCGCAttr())
458  removeObjCGCAttr();
459  if (getObjCLifetime() == Q.getObjCLifetime())
460  removeObjCLifetime();
461  if (getAddressSpace() == Q.getAddressSpace())
462  removeAddressSpace();
463  }
464  }
465 
466  /// Add the qualifiers from the given set to this set, given that
467  /// they don't conflict.
469  assert(getAddressSpace() == qs.getAddressSpace() ||
470  !hasAddressSpace() || !qs.hasAddressSpace());
471  assert(getObjCGCAttr() == qs.getObjCGCAttr() ||
472  !hasObjCGCAttr() || !qs.hasObjCGCAttr());
473  assert(getObjCLifetime() == qs.getObjCLifetime() ||
474  !hasObjCLifetime() || !qs.hasObjCLifetime());
475  Mask |= qs.Mask;
476  }
477 
478  /// Returns true if this address space is a superset of the other one.
479  /// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
480  /// overlapping address spaces.
481  /// CL1.1 or CL1.2:
482  /// every address space is a superset of itself.
483  /// CL2.0 adds:
484  /// __generic is a superset of any address space except for __constant.
486  return
487  // Address spaces must match exactly.
488  getAddressSpace() == other.getAddressSpace() ||
489  // Otherwise in OpenCLC v2.0 s6.5.5: every address space except
490  // for __constant can be used as __generic.
491  (getAddressSpace() == LangAS::opencl_generic &&
493  }
494 
495  /// Determines if these qualifiers compatibly include another set.
496  /// Generally this answers the question of whether an object with the other
497  /// qualifiers can be safely used as an object with these qualifiers.
498  bool compatiblyIncludes(Qualifiers other) const {
499  return isAddressSpaceSupersetOf(other) &&
500  // ObjC GC qualifiers can match, be added, or be removed, but can't
501  // be changed.
502  (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
503  !other.hasObjCGCAttr()) &&
504  // ObjC lifetime qualifiers must match exactly.
505  getObjCLifetime() == other.getObjCLifetime() &&
506  // CVR qualifiers may subset.
507  (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
508  // U qualifier may superset.
509  (!other.hasUnaligned() || hasUnaligned());
510  }
511 
512  /// Determines if these qualifiers compatibly include another set of
513  /// qualifiers from the narrow perspective of Objective-C ARC lifetime.
514  ///
515  /// One set of Objective-C lifetime qualifiers compatibly includes the other
516  /// if the lifetime qualifiers match, or if both are non-__weak and the
517  /// including set also contains the 'const' qualifier, or both are non-__weak
518  /// and one is None (which can only happen in non-ARC modes).
520  if (getObjCLifetime() == other.getObjCLifetime())
521  return true;
522 
523  if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
524  return false;
525 
526  if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
527  return true;
528 
529  return hasConst();
530  }
531 
532  /// Determine whether this set of qualifiers is a strict superset of
533  /// another set of qualifiers, not considering qualifier compatibility.
534  bool isStrictSupersetOf(Qualifiers Other) const;
535 
536  bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
537  bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
538 
539  explicit operator bool() const { return hasQualifiers(); }
540 
542  addQualifiers(R);
543  return *this;
544  }
545 
546  // Union two qualifier sets. If an enumerated qualifier appears
547  // in both sets, use the one from the right.
549  L += R;
550  return L;
551  }
552 
554  removeQualifiers(R);
555  return *this;
556  }
557 
558  /// Compute the difference between two qualifier sets.
560  L -= R;
561  return L;
562  }
563 
564  std::string getAsString() const;
565  std::string getAsString(const PrintingPolicy &Policy) const;
566 
567  bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
568  void print(raw_ostream &OS, const PrintingPolicy &Policy,
569  bool appendSpaceIfNonEmpty = false) const;
570 
571  void Profile(llvm::FoldingSetNodeID &ID) const {
572  ID.AddInteger(Mask);
573  }
574 
575 private:
576  // bits: |0 1 2|3|4 .. 5|6 .. 8|9 ... 31|
577  // |C R V|U|GCAttr|Lifetime|AddressSpace|
578  uint32_t Mask = 0;
579 
580  static const uint32_t UMask = 0x8;
581  static const uint32_t UShift = 3;
582  static const uint32_t GCAttrMask = 0x30;
583  static const uint32_t GCAttrShift = 4;
584  static const uint32_t LifetimeMask = 0x1C0;
585  static const uint32_t LifetimeShift = 6;
586  static const uint32_t AddressSpaceMask =
587  ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
588  static const uint32_t AddressSpaceShift = 9;
589 };
590 
591 /// A std::pair-like structure for storing a qualified type split
592 /// into its local qualifiers and its locally-unqualified type.
594  /// The locally-unqualified type.
595  const Type *Ty = nullptr;
596 
597  /// The local qualifiers.
599 
600  SplitQualType() = default;
601  SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
602 
603  SplitQualType getSingleStepDesugaredType() const; // end of this file
604 
605  // Make std::tie work.
606  std::pair<const Type *,Qualifiers> asPair() const {
607  return std::pair<const Type *, Qualifiers>(Ty, Quals);
608  }
609 
611  return a.Ty == b.Ty && a.Quals == b.Quals;
612  }
614  return a.Ty != b.Ty || a.Quals != b.Quals;
615  }
616 };
617 
618 /// The kind of type we are substituting Objective-C type arguments into.
619 ///
620 /// The kind of substitution affects the replacement of type parameters when
621 /// no concrete type information is provided, e.g., when dealing with an
622 /// unspecialized type.
624  /// An ordinary type.
625  Ordinary,
626 
627  /// The result type of a method or function.
628  Result,
629 
630  /// The parameter type of a method or function.
631  Parameter,
632 
633  /// The type of a property.
634  Property,
635 
636  /// The superclass of a type.
637  Superclass,
638 };
639 
640 /// A (possibly-)qualified type.
641 ///
642 /// For efficiency, we don't store CV-qualified types as nodes on their
643 /// own: instead each reference to a type stores the qualifiers. This
644 /// greatly reduces the number of nodes we need to allocate for types (for
645 /// example we only need one for 'int', 'const int', 'volatile int',
646 /// 'const volatile int', etc).
647 ///
648 /// As an added efficiency bonus, instead of making this a pair, we
649 /// just store the two bits we care about in the low bits of the
650 /// pointer. To handle the packing/unpacking, we make QualType be a
651 /// simple wrapper class that acts like a smart pointer. A third bit
652 /// indicates whether there are extended qualifiers present, in which
653 /// case the pointer points to a special structure.
654 class QualType {
655  friend class QualifierCollector;
656 
657  // Thankfully, these are efficiently composable.
658  llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
660 
661  const ExtQuals *getExtQualsUnsafe() const {
662  return Value.getPointer().get<const ExtQuals*>();
663  }
664 
665  const Type *getTypePtrUnsafe() const {
666  return Value.getPointer().get<const Type*>();
667  }
668 
669  const ExtQualsTypeCommonBase *getCommonPtr() const {
670  assert(!isNull() && "Cannot retrieve a NULL type pointer");
671  auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
672  CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
673  return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
674  }
675 
676 public:
677  QualType() = default;
678  QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
679  QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
680 
681  unsigned getLocalFastQualifiers() const { return Value.getInt(); }
682  void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
683 
684  /// Retrieves a pointer to the underlying (unqualified) type.
685  ///
686  /// This function requires that the type not be NULL. If the type might be
687  /// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
688  const Type *getTypePtr() const;
689 
690  const Type *getTypePtrOrNull() const;
691 
692  /// Retrieves a pointer to the name of the base type.
693  const IdentifierInfo *getBaseTypeIdentifier() const;
694 
695  /// Divides a QualType into its unqualified type and a set of local
696  /// qualifiers.
697  SplitQualType split() const;
698 
699  void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
700 
701  static QualType getFromOpaquePtr(const void *Ptr) {
702  QualType T;
703  T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
704  return T;
705  }
706 
707  const Type &operator*() const {
708  return *getTypePtr();
709  }
710 
711  const Type *operator->() const {
712  return getTypePtr();
713  }
714 
715  bool isCanonical() const;
716  bool isCanonicalAsParam() const;
717 
718  /// Return true if this QualType doesn't point to a type yet.
719  bool isNull() const {
720  return Value.getPointer().isNull();
721  }
722 
723  /// Determine whether this particular QualType instance has the
724  /// "const" qualifier set, without looking through typedefs that may have
725  /// added "const" at a different level.
726  bool isLocalConstQualified() const {
727  return (getLocalFastQualifiers() & Qualifiers::Const);
728  }
729 
730  /// Determine whether this type is const-qualified.
731  bool isConstQualified() const;
732 
733  /// Determine whether this particular QualType instance has the
734  /// "restrict" qualifier set, without looking through typedefs that may have
735  /// added "restrict" at a different level.
737  return (getLocalFastQualifiers() & Qualifiers::Restrict);
738  }
739 
740  /// Determine whether this type is restrict-qualified.
741  bool isRestrictQualified() const;
742 
743  /// Determine whether this particular QualType instance has the
744  /// "volatile" qualifier set, without looking through typedefs that may have
745  /// added "volatile" at a different level.
747  return (getLocalFastQualifiers() & Qualifiers::Volatile);
748  }
749 
750  /// Determine whether this type is volatile-qualified.
751  bool isVolatileQualified() const;
752 
753  /// Determine whether this particular QualType instance has any
754  /// qualifiers, without looking through any typedefs that might add
755  /// qualifiers at a different level.
756  bool hasLocalQualifiers() const {
757  return getLocalFastQualifiers() || hasLocalNonFastQualifiers();
758  }
759 
760  /// Determine whether this type has any qualifiers.
761  bool hasQualifiers() const;
762 
763  /// Determine whether this particular QualType instance has any
764  /// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
765  /// instance.
767  return Value.getPointer().is<const ExtQuals*>();
768  }
769 
770  /// Retrieve the set of qualifiers local to this particular QualType
771  /// instance, not including any qualifiers acquired through typedefs or
772  /// other sugar.
773  Qualifiers getLocalQualifiers() const;
774 
775  /// Retrieve the set of qualifiers applied to this type.
776  Qualifiers getQualifiers() const;
777 
778  /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
779  /// local to this particular QualType instance, not including any qualifiers
780  /// acquired through typedefs or other sugar.
781  unsigned getLocalCVRQualifiers() const {
782  return getLocalFastQualifiers();
783  }
784 
785  /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
786  /// applied to this type.
787  unsigned getCVRQualifiers() const;
788 
789  bool isConstant(const ASTContext& Ctx) const {
790  return QualType::isConstant(*this, Ctx);
791  }
792 
793  /// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
794  bool isPODType(const ASTContext &Context) const;
795 
796  /// Return true if this is a POD type according to the rules of the C++98
797  /// standard, regardless of the current compilation's language.
798  bool isCXX98PODType(const ASTContext &Context) const;
799 
800  /// Return true if this is a POD type according to the more relaxed rules
801  /// of the C++11 standard, regardless of the current compilation's language.
802  /// (C++0x [basic.types]p9). Note that, unlike
803  /// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
804  bool isCXX11PODType(const ASTContext &Context) const;
805 
806  /// Return true if this is a trivial type per (C++0x [basic.types]p9)
807  bool isTrivialType(const ASTContext &Context) const;
808 
809  /// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
810  bool isTriviallyCopyableType(const ASTContext &Context) const;
811 
812  // Don't promise in the API that anything besides 'const' can be
813  // easily added.
814 
815  /// Add the `const` type qualifier to this QualType.
816  void addConst() {
817  addFastQualifiers(Qualifiers::Const);
818  }
819  QualType withConst() const {
820  return withFastQualifiers(Qualifiers::Const);
821  }
822 
823  /// Add the `volatile` type qualifier to this QualType.
824  void addVolatile() {
825  addFastQualifiers(Qualifiers::Volatile);
826  }
828  return withFastQualifiers(Qualifiers::Volatile);
829  }
830 
831  /// Add the `restrict` qualifier to this QualType.
832  void addRestrict() {
833  addFastQualifiers(Qualifiers::Restrict);
834  }
836  return withFastQualifiers(Qualifiers::Restrict);
837  }
838 
839  QualType withCVRQualifiers(unsigned CVR) const {
840  return withFastQualifiers(CVR);
841  }
842 
843  void addFastQualifiers(unsigned TQs) {
844  assert(!(TQs & ~Qualifiers::FastMask)
845  && "non-fast qualifier bits set in mask!");
846  Value.setInt(Value.getInt() | TQs);
847  }
848 
849  void removeLocalConst();
850  void removeLocalVolatile();
851  void removeLocalRestrict();
852  void removeLocalCVRQualifiers(unsigned Mask);
853 
854  void removeLocalFastQualifiers() { Value.setInt(0); }
855  void removeLocalFastQualifiers(unsigned Mask) {
856  assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers");
857  Value.setInt(Value.getInt() & ~Mask);
858  }
859 
860  // Creates a type with the given qualifiers in addition to any
861  // qualifiers already on this type.
862  QualType withFastQualifiers(unsigned TQs) const {
863  QualType T = *this;
864  T.addFastQualifiers(TQs);
865  return T;
866  }
867 
868  // Creates a type with exactly the given fast qualifiers, removing
869  // any existing fast qualifiers.
871  return withoutLocalFastQualifiers().withFastQualifiers(TQs);
872  }
873 
874  // Removes fast qualifiers, but leaves any extended qualifiers in place.
876  QualType T = *this;
878  return T;
879  }
880 
881  QualType getCanonicalType() const;
882 
883  /// Return this type with all of the instance-specific qualifiers
884  /// removed, but without removing any qualifiers that may have been applied
885  /// through typedefs.
886  QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }
887 
888  /// Retrieve the unqualified variant of the given type,
889  /// removing as little sugar as possible.
890  ///
891  /// This routine looks through various kinds of sugar to find the
892  /// least-desugared type that is unqualified. For example, given:
893  ///
894  /// \code
895  /// typedef int Integer;
896  /// typedef const Integer CInteger;
897  /// typedef CInteger DifferenceType;
898  /// \endcode
899  ///
900  /// Executing \c getUnqualifiedType() on the type \c DifferenceType will
901  /// desugar until we hit the type \c Integer, which has no qualifiers on it.
902  ///
903  /// The resulting type might still be qualified if it's sugar for an array
904  /// type. To strip qualifiers even from within a sugared array type, use
905  /// ASTContext::getUnqualifiedArrayType.
906  inline QualType getUnqualifiedType() const;
907 
908  /// Retrieve the unqualified variant of the given type, removing as little
909  /// sugar as possible.
910  ///
911  /// Like getUnqualifiedType(), but also returns the set of
912  /// qualifiers that were built up.
913  ///
914  /// The resulting type might still be qualified if it's sugar for an array
915  /// type. To strip qualifiers even from within a sugared array type, use
916  /// ASTContext::getUnqualifiedArrayType.
917  inline SplitQualType getSplitUnqualifiedType() const;
918 
919  /// Determine whether this type is more qualified than the other
920  /// given type, requiring exact equality for non-CVR qualifiers.
921  bool isMoreQualifiedThan(QualType Other) const;
922 
923  /// Determine whether this type is at least as qualified as the other
924  /// given type, requiring exact equality for non-CVR qualifiers.
925  bool isAtLeastAsQualifiedAs(QualType Other) const;
926 
927  QualType getNonReferenceType() const;
928 
929  /// Determine the type of a (typically non-lvalue) expression with the
930  /// specified result type.
931  ///
932  /// This routine should be used for expressions for which the return type is
933  /// explicitly specified (e.g., in a cast or call) and isn't necessarily
934  /// an lvalue. It removes a top-level reference (since there are no
935  /// expressions of reference type) and deletes top-level cvr-qualifiers
936  /// from non-class types (in C++) or all types (in C).
937  QualType getNonLValueExprType(const ASTContext &Context) const;
938 
939  /// Return the specified type with any "sugar" removed from
940  /// the type. This takes off typedefs, typeof's etc. If the outer level of
941  /// the type is already concrete, it returns it unmodified. This is similar
942  /// to getting the canonical type, but it doesn't remove *all* typedefs. For
943  /// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
944  /// concrete.
945  ///
946  /// Qualifiers are left in place.
947  QualType getDesugaredType(const ASTContext &Context) const {
948  return getDesugaredType(*this, Context);
949  }
950 
952  return getSplitDesugaredType(*this);
953  }
954 
955  /// Return the specified type with one level of "sugar" removed from
956  /// the type.
957  ///
958  /// This routine takes off the first typedef, typeof, etc. If the outer level
959  /// of the type is already concrete, it returns it unmodified.
961  return getSingleStepDesugaredTypeImpl(*this, Context);
962  }
963 
964  /// Returns the specified type after dropping any
965  /// outer-level parentheses.
967  if (isa<ParenType>(*this))
968  return QualType::IgnoreParens(*this);
969  return *this;
970  }
971 
972  /// Indicate whether the specified types and qualifiers are identical.
973  friend bool operator==(const QualType &LHS, const QualType &RHS) {
974  return LHS.Value == RHS.Value;
975  }
976  friend bool operator!=(const QualType &LHS, const QualType &RHS) {
977  return LHS.Value != RHS.Value;
978  }
979 
980  static std::string getAsString(SplitQualType split,
981  const PrintingPolicy &Policy) {
982  return getAsString(split.Ty, split.Quals, Policy);
983  }
984  static std::string getAsString(const Type *ty, Qualifiers qs,
985  const PrintingPolicy &Policy);
986 
987  std::string getAsString() const;
988  std::string getAsString(const PrintingPolicy &Policy) const;
989 
990  void print(raw_ostream &OS, const PrintingPolicy &Policy,
991  const Twine &PlaceHolder = Twine(),
992  unsigned Indentation = 0) const {
993  print(split(), OS, Policy, PlaceHolder, Indentation);
994  }
995 
996  static void print(SplitQualType split, raw_ostream &OS,
997  const PrintingPolicy &policy, const Twine &PlaceHolder,
998  unsigned Indentation = 0) {
999  return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
1000  }
1001 
1002  static void print(const Type *ty, Qualifiers qs,
1003  raw_ostream &OS, const PrintingPolicy &policy,
1004  const Twine &PlaceHolder,
1005  unsigned Indentation = 0);
1006 
1007  void getAsStringInternal(std::string &Str,
1008  const PrintingPolicy &Policy) const {
1009  return getAsStringInternal(split(), Str, Policy);
1010  }
1011 
1012  static void getAsStringInternal(SplitQualType split, std::string &out,
1013  const PrintingPolicy &policy) {
1014  return getAsStringInternal(split.Ty, split.Quals, out, policy);
1015  }
1016 
1017  static void getAsStringInternal(const Type *ty, Qualifiers qs,
1018  std::string &out,
1019  const PrintingPolicy &policy);
1020 
1022  const QualType &T;
1023  const PrintingPolicy &Policy;
1024  const Twine &PlaceHolder;
1025  unsigned Indentation;
1026 
1027  public:
1029  const Twine &PlaceHolder, unsigned Indentation)
1030  : T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1031  Indentation(Indentation) {}
1032 
1033  friend raw_ostream &operator<<(raw_ostream &OS,
1034  const StreamedQualTypeHelper &SQT) {
1035  SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
1036  return OS;
1037  }
1038  };
1039 
1041  const Twine &PlaceHolder = Twine(),
1042  unsigned Indentation = 0) const {
1043  return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1044  }
1045 
1046  void dump(const char *s) const;
1047  void dump() const;
1048  void dump(llvm::raw_ostream &OS) const;
1049 
1050  void Profile(llvm::FoldingSetNodeID &ID) const {
1051  ID.AddPointer(getAsOpaquePtr());
1052  }
1053 
1054  /// Return the address space of this type.
1055  inline LangAS getAddressSpace() const;
1056 
1057  /// Returns gc attribute of this type.
1058  inline Qualifiers::GC getObjCGCAttr() const;
1059 
1060  /// true when Type is objc's weak.
1061  bool isObjCGCWeak() const {
1062  return getObjCGCAttr() == Qualifiers::Weak;
1063  }
1064 
1065  /// true when Type is objc's strong.
1066  bool isObjCGCStrong() const {
1067  return getObjCGCAttr() == Qualifiers::Strong;
1068  }
1069 
1070  /// Returns lifetime attribute of this type.
1072  return getQualifiers().getObjCLifetime();
1073  }
1074 
1076  return getQualifiers().hasNonTrivialObjCLifetime();
1077  }
1078 
1080  return getQualifiers().hasStrongOrWeakObjCLifetime();
1081  }
1082 
1083  // true when Type is objc's weak and weak is enabled but ARC isn't.
1084  bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1085 
1087  /// The type does not fall into any of the following categories. Note that
1088  /// this case is zero-valued so that values of this enum can be used as a
1089  /// boolean condition for non-triviality.
1091 
1092  /// The type is an Objective-C retainable pointer type that is qualified
1093  /// with the ARC __strong qualifier.
1095 
1096  /// The type is an Objective-C retainable pointer type that is qualified
1097  /// with the ARC __weak qualifier.
1099 
1100  /// The type is a struct containing a field whose type is not PCK_Trivial.
1101  PDIK_Struct
1102  };
1103 
1104  /// Functions to query basic properties of non-trivial C struct types.
1105 
1106  /// Check if this is a non-trivial type that would cause a C struct
1107  /// transitively containing this type to be non-trivial to default initialize
1108  /// and return the kind.
1110  isNonTrivialToPrimitiveDefaultInitialize() const;
1111 
1113  /// The type does not fall into any of the following categories. Note that
1114  /// this case is zero-valued so that values of this enum can be used as a
1115  /// boolean condition for non-triviality.
1117 
1118  /// The type would be trivial except that it is volatile-qualified. Types
1119  /// that fall into one of the other non-trivial cases may additionally be
1120  /// volatile-qualified.
1122 
1123  /// The type is an Objective-C retainable pointer type that is qualified
1124  /// with the ARC __strong qualifier.
1126 
1127  /// The type is an Objective-C retainable pointer type that is qualified
1128  /// with the ARC __weak qualifier.
1130 
1131  /// The type is a struct containing a field whose type is neither
1132  /// PCK_Trivial nor PCK_VolatileTrivial.
1133  /// Note that a C++ struct type does not necessarily match this; C++ copying
1134  /// semantics are too complex to express here, in part because they depend
1135  /// on the exact constructor or assignment operator that is chosen by
1136  /// overload resolution to do the copy.
1137  PCK_Struct
1138  };
1139 
1140  /// Check if this is a non-trivial type that would cause a C struct
1141  /// transitively containing this type to be non-trivial to copy and return the
1142  /// kind.
1143  PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;
1144 
1145  /// Check if this is a non-trivial type that would cause a C struct
1146  /// transitively containing this type to be non-trivial to destructively
1147  /// move and return the kind. Destructive move in this context is a C++-style
1148  /// move in which the source object is placed in a valid but unspecified state
1149  /// after it is moved, as opposed to a truly destructive move in which the
1150  /// source object is placed in an uninitialized state.
1151  PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;
1152 
1158  DK_nontrivial_c_struct
1159  };
1160 
1161  /// Returns a nonzero value if objects of this type require
1162  /// non-trivial work to clean up after. Non-zero because it's
1163  /// conceivable that qualifiers (objc_gc(weak)?) could make
1164  /// something require destruction.
1166  return isDestructedTypeImpl(*this);
1167  }
1168 
1169  /// Determine whether expressions of the given type are forbidden
1170  /// from being lvalues in C.
1171  ///
1172  /// The expression types that are forbidden to be lvalues are:
1173  /// - 'void', but not qualified void
1174  /// - function types
1175  ///
1176  /// The exact rule here is C99 6.3.2.1:
1177  /// An lvalue is an expression with an object type or an incomplete
1178  /// type other than void.
1179  bool isCForbiddenLValueType() const;
1180 
1181  /// Substitute type arguments for the Objective-C type parameters used in the
1182  /// subject type.
1183  ///
1184  /// \param ctx ASTContext in which the type exists.
1185  ///
1186  /// \param typeArgs The type arguments that will be substituted for the
1187  /// Objective-C type parameters in the subject type, which are generally
1188  /// computed via \c Type::getObjCSubstitutions. If empty, the type
1189  /// parameters will be replaced with their bounds or id/Class, as appropriate
1190  /// for the context.
1191  ///
1192  /// \param context The context in which the subject type was written.
1193  ///
1194  /// \returns the resulting type.
1195  QualType substObjCTypeArgs(ASTContext &ctx,
1196  ArrayRef<QualType> typeArgs,
1197  ObjCSubstitutionContext context) const;
1198 
1199  /// Substitute type arguments from an object type for the Objective-C type
1200  /// parameters used in the subject type.
1201  ///
1202  /// This operation combines the computation of type arguments for
1203  /// substitution (\c Type::getObjCSubstitutions) with the actual process of
1204  /// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1205  /// callers that need to perform a single substitution in isolation.
1206  ///
1207  /// \param objectType The type of the object whose member type we're
1208  /// substituting into. For example, this might be the receiver of a message
1209  /// or the base of a property access.
1210  ///
1211  /// \param dc The declaration context from which the subject type was
1212  /// retrieved, which indicates (for example) which type parameters should
1213  /// be substituted.
1214  ///
1215  /// \param context The context in which the subject type was written.
1216  ///
1217  /// \returns the subject type after replacing all of the Objective-C type
1218  /// parameters with their corresponding arguments.
1219  QualType substObjCMemberType(QualType objectType,
1220  const DeclContext *dc,
1221  ObjCSubstitutionContext context) const;
1222 
1223  /// Strip Objective-C "__kindof" types from the given type.
1224  QualType stripObjCKindOfType(const ASTContext &ctx) const;
1225 
1226  /// Remove all qualifiers including _Atomic.
1227  QualType getAtomicUnqualifiedType() const;
1228 
1229 private:
1230  // These methods are implemented in a separate translation unit;
1231  // "static"-ize them to avoid creating temporary QualTypes in the
1232  // caller.
1233  static bool isConstant(QualType T, const ASTContext& Ctx);
1234  static QualType getDesugaredType(QualType T, const ASTContext &Context);
1235  static SplitQualType getSplitDesugaredType(QualType T);
1236  static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1237  static QualType getSingleStepDesugaredTypeImpl(QualType type,
1238  const ASTContext &C);
1239  static QualType IgnoreParens(QualType T);
1240  static DestructionKind isDestructedTypeImpl(QualType type);
1241 };
1242 
1243 } // namespace clang
1244 
1245 namespace llvm {
1246 
1247 /// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1248 /// to a specific Type class.
1249 template<> struct simplify_type< ::clang::QualType> {
1251 
1253  return Val.getTypePtr();
1254  }
1255 };
1256 
1257 // Teach SmallPtrSet that QualType is "basically a pointer".
1258 template<>
1259 struct PointerLikeTypeTraits<clang::QualType> {
1260  static inline void *getAsVoidPointer(clang::QualType P) {
1261  return P.getAsOpaquePtr();
1262  }
1263 
1264  static inline clang::QualType getFromVoidPointer(void *P) {
1266  }
1267 
1268  // Various qualifiers go in low bits.
1269  enum { NumLowBitsAvailable = 0 };
1270 };
1271 
1272 } // namespace llvm
1273 
1274 namespace clang {
1275 
1276 /// Base class that is common to both the \c ExtQuals and \c Type
1277 /// classes, which allows \c QualType to access the common fields between the
1278 /// two.
1280  friend class ExtQuals;
1281  friend class QualType;
1282  friend class Type;
1283 
1284  /// The "base" type of an extended qualifiers type (\c ExtQuals) or
1285  /// a self-referential pointer (for \c Type).
1286  ///
1287  /// This pointer allows an efficient mapping from a QualType to its
1288  /// underlying type pointer.
1289  const Type *const BaseType;
1290 
1291  /// The canonical type of this type. A QualType.
1292  QualType CanonicalType;
1293 
1294  ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1295  : BaseType(baseType), CanonicalType(canon) {}
1296 };
1297 
1298 /// We can encode up to four bits in the low bits of a
1299 /// type pointer, but there are many more type qualifiers that we want
1300 /// to be able to apply to an arbitrary type. Therefore we have this
1301 /// struct, intended to be heap-allocated and used by QualType to
1302 /// store qualifiers.
1303 ///
1304 /// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1305 /// in three low bits on the QualType pointer; a fourth bit records whether
1306 /// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1307 /// Objective-C GC attributes) are much more rare.
1308 class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
1309  // NOTE: changing the fast qualifiers should be straightforward as
1310  // long as you don't make 'const' non-fast.
1311  // 1. Qualifiers:
1312  // a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1313  // Fast qualifiers must occupy the low-order bits.
1314  // b) Update Qualifiers::FastWidth and FastMask.
1315  // 2. QualType:
1316  // a) Update is{Volatile,Restrict}Qualified(), defined inline.
1317  // b) Update remove{Volatile,Restrict}, defined near the end of
1318  // this header.
1319  // 3. ASTContext:
1320  // a) Update get{Volatile,Restrict}Type.
1321 
1322  /// The immutable set of qualifiers applied by this node. Always contains
1323  /// extended qualifiers.
1324  Qualifiers Quals;
1325 
1326  ExtQuals *this_() { return this; }
1327 
1328 public:
1329  ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1330  : ExtQualsTypeCommonBase(baseType,
1331  canon.isNull() ? QualType(this_(), 0) : canon),
1332  Quals(quals) {
1333  assert(Quals.hasNonFastQualifiers()
1334  && "ExtQuals created with no fast qualifiers");
1335  assert(!Quals.hasFastQualifiers()
1336  && "ExtQuals created with fast qualifiers");
1337  }
1338 
1339  Qualifiers getQualifiers() const { return Quals; }
1340 
1341  bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1342  Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1343 
1344  bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1346  return Quals.getObjCLifetime();
1347  }
1348 
1349  bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1350  LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1351 
1352  const Type *getBaseType() const { return BaseType; }
1353 
1354 public:
1355  void Profile(llvm::FoldingSetNodeID &ID) const {
1356  Profile(ID, getBaseType(), Quals);
1357  }
1358 
1359  static void Profile(llvm::FoldingSetNodeID &ID,
1360  const Type *BaseType,
1361  Qualifiers Quals) {
1362  assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!");
1363  ID.AddPointer(BaseType);
1364  Quals.Profile(ID);
1365  }
1366 };
1367 
1368 /// The kind of C++11 ref-qualifier associated with a function type.
1369 /// This determines whether a member function's "this" object can be an
1370 /// lvalue, rvalue, or neither.
1372  /// No ref-qualifier was provided.
1373  RQ_None = 0,
1374 
1375  /// An lvalue ref-qualifier was provided (\c &).
1377 
1378  /// An rvalue ref-qualifier was provided (\c &&).
1380 };
1381 
1382 /// Which keyword(s) were used to create an AutoType.
1383 enum class AutoTypeKeyword {
1384  /// auto
1385  Auto,
1386 
1387  /// decltype(auto)
1388  DecltypeAuto,
1389 
1390  /// __auto_type (GNU extension)
1391  GNUAutoType
1392 };
1393 
1394 /// The base class of the type hierarchy.
1395 ///
1396 /// A central concept with types is that each type always has a canonical
1397 /// type. A canonical type is the type with any typedef names stripped out
1398 /// of it or the types it references. For example, consider:
1399 ///
1400 /// typedef int foo;
1401 /// typedef foo* bar;
1402 /// 'int *' 'foo *' 'bar'
1403 ///
1404 /// There will be a Type object created for 'int'. Since int is canonical, its
1405 /// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1406 /// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1407 /// there is a PointerType that represents 'int*', which, like 'int', is
1408 /// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1409 /// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1410 /// is also 'int*'.
1411 ///
1412 /// Non-canonical types are useful for emitting diagnostics, without losing
1413 /// information about typedefs being used. Canonical types are useful for type
1414 /// comparisons (they allow by-pointer equality tests) and useful for reasoning
1415 /// about whether something has a particular form (e.g. is a function type),
1416 /// because they implicitly, recursively, strip all typedefs out of a type.
1417 ///
1418 /// Types, once created, are immutable.
1419 ///
1421 public:
1422  enum TypeClass {
1423 #define TYPE(Class, Base) Class,
1424 #define LAST_TYPE(Class) TypeLast = Class,
1425 #define ABSTRACT_TYPE(Class, Base)
1426 #include "clang/AST/TypeNodes.def"
1427  TagFirst = Record, TagLast = Enum
1428  };
1429 
1430 private:
1431  /// Bitfields required by the Type class.
1432  class TypeBitfields {
1433  friend class Type;
1434  template <class T> friend class TypePropertyCache;
1435 
1436  /// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1437  unsigned TC : 8;
1438 
1439  /// Whether this type is a dependent type (C++ [temp.dep.type]).
1440  unsigned Dependent : 1;
1441 
1442  /// Whether this type somehow involves a template parameter, even
1443  /// if the resolution of the type does not depend on a template parameter.
1444  unsigned InstantiationDependent : 1;
1445 
1446  /// Whether this type is a variably-modified type (C99 6.7.5).
1447  unsigned VariablyModified : 1;
1448 
1449  /// Whether this type contains an unexpanded parameter pack
1450  /// (for C++11 variadic templates).
1451  unsigned ContainsUnexpandedParameterPack : 1;
1452 
1453  /// True if the cache (i.e. the bitfields here starting with
1454  /// 'Cache') is valid.
1455  mutable unsigned CacheValid : 1;
1456 
1457  /// Linkage of this type.
1458  mutable unsigned CachedLinkage : 3;
1459 
1460  /// Whether this type involves and local or unnamed types.
1461  mutable unsigned CachedLocalOrUnnamed : 1;
1462 
1463  /// Whether this type comes from an AST file.
1464  mutable unsigned FromAST : 1;
1465 
1466  bool isCacheValid() const {
1467  return CacheValid;
1468  }
1469 
1470  Linkage getLinkage() const {
1471  assert(isCacheValid() && "getting linkage from invalid cache");
1472  return static_cast<Linkage>(CachedLinkage);
1473  }
1474 
1475  bool hasLocalOrUnnamedType() const {
1476  assert(isCacheValid() && "getting linkage from invalid cache");
1477  return CachedLocalOrUnnamed;
1478  }
1479  };
1480  enum { NumTypeBits = 18 };
1481 
1482 protected:
1483  // These classes allow subclasses to somewhat cleanly pack bitfields
1484  // into Type.
1485 
1487  friend class ArrayType;
1488 
1489  unsigned : NumTypeBits;
1490 
1491  /// CVR qualifiers from declarations like
1492  /// 'int X[static restrict 4]'. For function parameters only.
1493  unsigned IndexTypeQuals : 3;
1494 
1495  /// Storage class qualifiers from declarations like
1496  /// 'int X[static restrict 4]'. For function parameters only.
1497  /// Actually an ArrayType::ArraySizeModifier.
1498  unsigned SizeModifier : 3;
1499  };
1500 
1502  friend class BuiltinType;
1503 
1504  unsigned : NumTypeBits;
1505 
1506  /// The kind (BuiltinType::Kind) of builtin type this is.
1507  unsigned Kind : 8;
1508  };
1509 
1511  friend class FunctionProtoType;
1512  friend class FunctionType;
1513 
1514  unsigned : NumTypeBits;
1515 
1516  /// Extra information which affects how the function is called, like
1517  /// regparm and the calling convention.
1518  unsigned ExtInfo : 12;
1519 
1520  /// Used only by FunctionProtoType, put here to pack with the
1521  /// other bitfields.
1522  /// The qualifiers are part of FunctionProtoType because...
1523  ///
1524  /// C++ 8.3.5p4: The return type, the parameter type list and the
1525  /// cv-qualifier-seq, [...], are part of the function type.
1526  unsigned TypeQuals : 4;
1527 
1528  /// The ref-qualifier associated with a \c FunctionProtoType.
1529  ///
1530  /// This is a value of type \c RefQualifierKind.
1531  unsigned RefQualifier : 2;
1532  };
1533 
1535  friend class ObjCObjectType;
1536 
1537  unsigned : NumTypeBits;
1538 
1539  /// The number of type arguments stored directly on this object type.
1540  unsigned NumTypeArgs : 7;
1541 
1542  /// The number of protocols stored directly on this object type.
1543  unsigned NumProtocols : 6;
1544 
1545  /// Whether this is a "kindof" type.
1546  unsigned IsKindOf : 1;
1547  };
1548 
1549  static_assert(NumTypeBits + 7 + 6 + 1 <= 32, "Does not fit in an unsigned");
1550 
1552  friend class ReferenceType;
1553 
1554  unsigned : NumTypeBits;
1555 
1556  /// True if the type was originally spelled with an lvalue sigil.
1557  /// This is never true of rvalue references but can also be false
1558  /// on lvalue references because of C++0x [dcl.typedef]p9,
1559  /// as follows:
1560  ///
1561  /// typedef int &ref; // lvalue, spelled lvalue
1562  /// typedef int &&rvref; // rvalue
1563  /// ref &a; // lvalue, inner ref, spelled lvalue
1564  /// ref &&a; // lvalue, inner ref
1565  /// rvref &a; // lvalue, inner ref, spelled lvalue
1566  /// rvref &&a; // rvalue, inner ref
1567  unsigned SpelledAsLValue : 1;
1568 
1569  /// True if the inner type is a reference type. This only happens
1570  /// in non-canonical forms.
1571  unsigned InnerRef : 1;
1572  };
1573 
1575  friend class TypeWithKeyword;
1576 
1577  unsigned : NumTypeBits;
1578 
1579  /// An ElaboratedTypeKeyword. 8 bits for efficient access.
1580  unsigned Keyword : 8;
1581  };
1582 
1584  friend class VectorType;
1585 
1586  unsigned : NumTypeBits;
1587 
1588  /// The kind of vector, either a generic vector type or some
1589  /// target-specific vector type such as for AltiVec or Neon.
1590  unsigned VecKind : 3;
1591 
1592  /// The number of elements in the vector.
1593  unsigned NumElements : 29 - NumTypeBits;
1594 
1595  enum { MaxNumElements = (1 << (29 - NumTypeBits)) - 1 };
1596  };
1597 
1599  friend class AttributedType;
1600 
1601  unsigned : NumTypeBits;
1602 
1603  /// An AttributedType::Kind
1604  unsigned AttrKind : 32 - NumTypeBits;
1605  };
1606 
1608  friend class AutoType;
1609 
1610  unsigned : NumTypeBits;
1611 
1612  /// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1613  /// or '__auto_type'? AutoTypeKeyword value.
1614  unsigned Keyword : 2;
1615  };
1616 
1617  union {
1618  TypeBitfields TypeBits;
1628  };
1629 
1630 private:
1631  template <class T> friend class TypePropertyCache;
1632 
1633  /// Set whether this type comes from an AST file.
1634  void setFromAST(bool V = true) const {
1635  TypeBits.FromAST = V;
1636  }
1637 
1638 protected:
1639  friend class ASTContext;
1640 
1641  Type(TypeClass tc, QualType canon, bool Dependent,
1642  bool InstantiationDependent, bool VariablyModified,
1643  bool ContainsUnexpandedParameterPack)
1644  : ExtQualsTypeCommonBase(this,
1645  canon.isNull() ? QualType(this_(), 0) : canon) {
1646  TypeBits.TC = tc;
1647  TypeBits.Dependent = Dependent;
1648  TypeBits.InstantiationDependent = Dependent || InstantiationDependent;
1649  TypeBits.VariablyModified = VariablyModified;
1650  TypeBits.ContainsUnexpandedParameterPack = ContainsUnexpandedParameterPack;
1651  TypeBits.CacheValid = false;
1652  TypeBits.CachedLocalOrUnnamed = false;
1653  TypeBits.CachedLinkage = NoLinkage;
1654  TypeBits.FromAST = false;
1655  }
1656 
1657  // silence VC++ warning C4355: 'this' : used in base member initializer list
1658  Type *this_() { return this; }
1659 
1660  void setDependent(bool D = true) {
1661  TypeBits.Dependent = D;
1662  if (D)
1663  TypeBits.InstantiationDependent = true;
1664  }
1665 
1666  void setInstantiationDependent(bool D = true) {
1667  TypeBits.InstantiationDependent = D; }
1668 
1669  void setVariablyModified(bool VM = true) { TypeBits.VariablyModified = VM; }
1670 
1671  void setContainsUnexpandedParameterPack(bool PP = true) {
1672  TypeBits.ContainsUnexpandedParameterPack = PP;
1673  }
1674 
1675 public:
1676  friend class ASTReader;
1677  friend class ASTWriter;
1678 
1679  Type(const Type &) = delete;
1680  Type &operator=(const Type &) = delete;
1681 
1682  TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
1683 
1684  /// Whether this type comes from an AST file.
1685  bool isFromAST() const { return TypeBits.FromAST; }
1686 
1687  /// Whether this type is or contains an unexpanded parameter
1688  /// pack, used to support C++0x variadic templates.
1689  ///
1690  /// A type that contains a parameter pack shall be expanded by the
1691  /// ellipsis operator at some point. For example, the typedef in the
1692  /// following example contains an unexpanded parameter pack 'T':
1693  ///
1694  /// \code
1695  /// template<typename ...T>
1696  /// struct X {
1697  /// typedef T* pointer_types; // ill-formed; T is a parameter pack.
1698  /// };
1699  /// \endcode
1700  ///
1701  /// Note that this routine does not specify which
1703  return TypeBits.ContainsUnexpandedParameterPack;
1704  }
1705 
1706  /// Determines if this type would be canonical if it had no further
1707  /// qualification.
1708  bool isCanonicalUnqualified() const {
1709  return CanonicalType == QualType(this, 0);
1710  }
1711 
1712  /// Pull a single level of sugar off of this locally-unqualified type.
1713  /// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
1714  /// or QualType::getSingleStepDesugaredType(const ASTContext&).
1715  QualType getLocallyUnqualifiedSingleStepDesugaredType() const;
1716 
1717  /// Types are partitioned into 3 broad categories (C99 6.2.5p1):
1718  /// object types, function types, and incomplete types.
1719 
1720  /// Return true if this is an incomplete type.
1721  /// A type that can describe objects, but which lacks information needed to
1722  /// determine its size (e.g. void, or a fwd declared struct). Clients of this
1723  /// routine will need to determine if the size is actually required.
1724  ///
1725  /// Def If non-null, and the type refers to some kind of declaration
1726  /// that can be completed (such as a C struct, C++ class, or Objective-C
1727  /// class), will be set to the declaration.
1728  bool isIncompleteType(NamedDecl **Def = nullptr) const;
1729 
1730  /// Return true if this is an incomplete or object
1731  /// type, in other words, not a function type.
1733  return !isFunctionType();
1734  }
1735 
1736  /// Determine whether this type is an object type.
1737  bool isObjectType() const {
1738  // C++ [basic.types]p8:
1739  // An object type is a (possibly cv-qualified) type that is not a
1740  // function type, not a reference type, and not a void type.
1741  return !isReferenceType() && !isFunctionType() && !isVoidType();
1742  }
1743 
1744  /// Return true if this is a literal type
1745  /// (C++11 [basic.types]p10)
1746  bool isLiteralType(const ASTContext &Ctx) const;
1747 
1748  /// Test if this type is a standard-layout type.
1749  /// (C++0x [basic.type]p9)
1750  bool isStandardLayoutType() const;
1751 
1752  /// Helper methods to distinguish type categories. All type predicates
1753  /// operate on the canonical type, ignoring typedefs and qualifiers.
1754 
1755  /// Returns true if the type is a builtin type.
1756  bool isBuiltinType() const;
1757 
1758  /// Test for a particular builtin type.
1759  bool isSpecificBuiltinType(unsigned K) const;
1760 
1761  /// Test for a type which does not represent an actual type-system type but
1762  /// is instead used as a placeholder for various convenient purposes within
1763  /// Clang. All such types are BuiltinTypes.
1764  bool isPlaceholderType() const;
1765  const BuiltinType *getAsPlaceholderType() const;
1766 
1767  /// Test for a specific placeholder type.
1768  bool isSpecificPlaceholderType(unsigned K) const;
1769 
1770  /// Test for a placeholder type other than Overload; see
1771  /// BuiltinType::isNonOverloadPlaceholderType.
1772  bool isNonOverloadPlaceholderType() const;
1773 
1774  /// isIntegerType() does *not* include complex integers (a GCC extension).
1775  /// isComplexIntegerType() can be used to test for complex integers.
1776  bool isIntegerType() const; // C99 6.2.5p17 (int, char, bool, enum)
1777  bool isEnumeralType() const;
1778  bool isBooleanType() const;
1779  bool isCharType() const;
1780  bool isWideCharType() const;
1781  bool isChar8Type() const;
1782  bool isChar16Type() const;
1783  bool isChar32Type() const;
1784  bool isAnyCharacterType() const;
1785  bool isIntegralType(const ASTContext &Ctx) const;
1786 
1787  /// Determine whether this type is an integral or enumeration type.
1788  bool isIntegralOrEnumerationType() const;
1789 
1790  /// Determine whether this type is an integral or unscoped enumeration type.
1791  bool isIntegralOrUnscopedEnumerationType() const;
1792 
1793  /// Floating point categories.
1794  bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
1795  /// isComplexType() does *not* include complex integers (a GCC extension).
1796  /// isComplexIntegerType() can be used to test for complex integers.
1797  bool isComplexType() const; // C99 6.2.5p11 (complex)
1798  bool isAnyComplexType() const; // C99 6.2.5p11 (complex) + Complex Int.
1799  bool isFloatingType() const; // C99 6.2.5p11 (real floating + complex)
1800  bool isHalfType() const; // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
1801  bool isFloat16Type() const; // C11 extension ISO/IEC TS 18661
1802  bool isRealType() const; // C99 6.2.5p17 (real floating + integer)
1803  bool isArithmeticType() const; // C99 6.2.5p18 (integer + floating)
1804  bool isVoidType() const; // C99 6.2.5p19
1805  bool isScalarType() const; // C99 6.2.5p21 (arithmetic + pointers)
1806  bool isAggregateType() const;
1807  bool isFundamentalType() const;
1808  bool isCompoundType() const;
1809 
1810  // Type Predicates: Check to see if this type is structurally the specified
1811  // type, ignoring typedefs and qualifiers.
1812  bool isFunctionType() const;
1813  bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
1814  bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
1815  bool isPointerType() const;
1816  bool isAnyPointerType() const; // Any C pointer or ObjC object pointer
1817  bool isBlockPointerType() const;
1818  bool isVoidPointerType() const;
1819  bool isReferenceType() const;
1820  bool isLValueReferenceType() const;
1821  bool isRValueReferenceType() const;
1822  bool isFunctionPointerType() const;
1823  bool isMemberPointerType() const;
1824  bool isMemberFunctionPointerType() const;
1825  bool isMemberDataPointerType() const;
1826  bool isArrayType() const;
1827  bool isConstantArrayType() const;
1828  bool isIncompleteArrayType() const;
1829  bool isVariableArrayType() const;
1830  bool isDependentSizedArrayType() const;
1831  bool isRecordType() const;
1832  bool isClassType() const;
1833  bool isStructureType() const;
1834  bool isObjCBoxableRecordType() const;
1835  bool isInterfaceType() const;
1836  bool isStructureOrClassType() const;
1837  bool isUnionType() const;
1838  bool isComplexIntegerType() const; // GCC _Complex integer type.
1839  bool isVectorType() const; // GCC vector type.
1840  bool isExtVectorType() const; // Extended vector type.
1841  bool isDependentAddressSpaceType() const; // value-dependent address space qualifier
1842  bool isObjCObjectPointerType() const; // pointer to ObjC object
1843  bool isObjCRetainableType() const; // ObjC object or block pointer
1844  bool isObjCLifetimeType() const; // (array of)* retainable type
1845  bool isObjCIndirectLifetimeType() const; // (pointer to)* lifetime type
1846  bool isObjCNSObjectType() const; // __attribute__((NSObject))
1847  bool isObjCIndependentClassType() const; // __attribute__((objc_independent_class))
1848  // FIXME: change this to 'raw' interface type, so we can used 'interface' type
1849  // for the common case.
1850  bool isObjCObjectType() const; // NSString or typeof(*(id)0)
1851  bool isObjCQualifiedInterfaceType() const; // NSString<foo>
1852  bool isObjCQualifiedIdType() const; // id<foo>
1853  bool isObjCQualifiedClassType() const; // Class<foo>
1854  bool isObjCObjectOrInterfaceType() const;
1855  bool isObjCIdType() const; // id
1856  bool isObjCInertUnsafeUnretainedType() const;
1857 
1858  /// Whether the type is Objective-C 'id' or a __kindof type of an
1859  /// object type, e.g., __kindof NSView * or __kindof id
1860  /// <NSCopying>.
1861  ///
1862  /// \param bound Will be set to the bound on non-id subtype types,
1863  /// which will be (possibly specialized) Objective-C class type, or
1864  /// null for 'id.
1865  bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
1866  const ObjCObjectType *&bound) const;
1867 
1868  bool isObjCClassType() const; // Class
1869 
1870  /// Whether the type is Objective-C 'Class' or a __kindof type of an
1871  /// Class type, e.g., __kindof Class <NSCopying>.
1872  ///
1873  /// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
1874  /// here because Objective-C's type system cannot express "a class
1875  /// object for a subclass of NSFoo".
1876  bool isObjCClassOrClassKindOfType() const;
1877 
1878  bool isBlockCompatibleObjCPointerType(ASTContext &ctx) const;
1879  bool isObjCSelType() const; // Class
1880  bool isObjCBuiltinType() const; // 'id' or 'Class'
1881  bool isObjCARCBridgableType() const;
1882  bool isCARCBridgableType() const;
1883  bool isTemplateTypeParmType() const; // C++ template type parameter
1884  bool isNullPtrType() const; // C++11 std::nullptr_t
1885  bool isAlignValT() const; // C++17 std::align_val_t
1886  bool isStdByteType() const; // C++17 std::byte
1887  bool isAtomicType() const; // C11 _Atomic()
1888 
1889 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
1890  bool is##Id##Type() const;
1891 #include "clang/Basic/OpenCLImageTypes.def"
1892 
1893  bool isImageType() const; // Any OpenCL image type
1894 
1895  bool isSamplerT() const; // OpenCL sampler_t
1896  bool isEventT() const; // OpenCL event_t
1897  bool isClkEventT() const; // OpenCL clk_event_t
1898  bool isQueueT() const; // OpenCL queue_t
1899  bool isReserveIDT() const; // OpenCL reserve_id_t
1900 
1901  bool isPipeType() const; // OpenCL pipe type
1902  bool isOpenCLSpecificType() const; // Any OpenCL specific type
1903 
1904  /// Determines if this type, which must satisfy
1905  /// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
1906  /// than implicitly __strong.
1907  bool isObjCARCImplicitlyUnretainedType() const;
1908 
1909  /// Return the implicit lifetime for this type, which must not be dependent.
1910  Qualifiers::ObjCLifetime getObjCARCImplicitLifetime() const;
1911 
1921  STK_FloatingComplex
1922  };
1923 
1924  /// Given that this is a scalar type, classify it.
1925  ScalarTypeKind getScalarTypeKind() const;
1926 
1927  /// Whether this type is a dependent type, meaning that its definition
1928  /// somehow depends on a template parameter (C++ [temp.dep.type]).
1929  bool isDependentType() const { return TypeBits.Dependent; }
1930 
1931  /// Determine whether this type is an instantiation-dependent type,
1932  /// meaning that the type involves a template parameter (even if the
1933  /// definition does not actually depend on the type substituted for that
1934  /// template parameter).
1936  return TypeBits.InstantiationDependent;
1937  }
1938 
1939  /// Determine whether this type is an undeduced type, meaning that
1940  /// it somehow involves a C++11 'auto' type or similar which has not yet been
1941  /// deduced.
1942  bool isUndeducedType() const;
1943 
1944  /// Whether this type is a variably-modified type (C99 6.7.5).
1945  bool isVariablyModifiedType() const { return TypeBits.VariablyModified; }
1946 
1947  /// Whether this type involves a variable-length array type
1948  /// with a definite size.
1949  bool hasSizedVLAType() const;
1950 
1951  /// Whether this type is or contains a local or unnamed type.
1952  bool hasUnnamedOrLocalType() const;
1953 
1954  bool isOverloadableType() const;
1955 
1956  /// Determine wither this type is a C++ elaborated-type-specifier.
1957  bool isElaboratedTypeSpecifier() const;
1958 
1959  bool canDecayToPointerType() const;
1960 
1961  /// Whether this type is represented natively as a pointer. This includes
1962  /// pointers, references, block pointers, and Objective-C interface,
1963  /// qualified id, and qualified interface types, as well as nullptr_t.
1964  bool hasPointerRepresentation() const;
1965 
1966  /// Whether this type can represent an objective pointer type for the
1967  /// purpose of GC'ability
1968  bool hasObjCPointerRepresentation() const;
1969 
1970  /// Determine whether this type has an integer representation
1971  /// of some sort, e.g., it is an integer type or a vector.
1972  bool hasIntegerRepresentation() const;
1973 
1974  /// Determine whether this type has an signed integer representation
1975  /// of some sort, e.g., it is an signed integer type or a vector.
1976  bool hasSignedIntegerRepresentation() const;
1977 
1978  /// Determine whether this type has an unsigned integer representation
1979  /// of some sort, e.g., it is an unsigned integer type or a vector.
1980  bool hasUnsignedIntegerRepresentation() const;
1981 
1982  /// Determine whether this type has a floating-point representation
1983  /// of some sort, e.g., it is a floating-point type or a vector thereof.
1984  bool hasFloatingRepresentation() const;
1985 
1986  // Type Checking Functions: Check to see if this type is structurally the
1987  // specified type, ignoring typedefs and qualifiers, and return a pointer to
1988  // the best type we can.
1989  const RecordType *getAsStructureType() const;
1990  /// NOTE: getAs*ArrayType are methods on ASTContext.
1991  const RecordType *getAsUnionType() const;
1992  const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
1993  const ObjCObjectType *getAsObjCInterfaceType() const;
1994 
1995  // The following is a convenience method that returns an ObjCObjectPointerType
1996  // for object declared using an interface.
1997  const ObjCObjectPointerType *getAsObjCInterfacePointerType() const;
1998  const ObjCObjectPointerType *getAsObjCQualifiedIdType() const;
1999  const ObjCObjectPointerType *getAsObjCQualifiedClassType() const;
2000  const ObjCObjectType *getAsObjCQualifiedInterfaceType() const;
2001 
2002  /// Retrieves the CXXRecordDecl that this type refers to, either
2003  /// because the type is a RecordType or because it is the injected-class-name
2004  /// type of a class template or class template partial specialization.
2005  CXXRecordDecl *getAsCXXRecordDecl() const;
2006 
2007  /// Retrieves the TagDecl that this type refers to, either
2008  /// because the type is a TagType or because it is the injected-class-name
2009  /// type of a class template or class template partial specialization.
2010  TagDecl *getAsTagDecl() const;
2011 
2012  /// If this is a pointer or reference to a RecordType, return the
2013  /// CXXRecordDecl that the type refers to.
2014  ///
2015  /// If this is not a pointer or reference, or the type being pointed to does
2016  /// not refer to a CXXRecordDecl, returns NULL.
2017  const CXXRecordDecl *getPointeeCXXRecordDecl() const;
2018 
2019  /// Get the DeducedType whose type will be deduced for a variable with
2020  /// an initializer of this type. This looks through declarators like pointer
2021  /// types, but not through decltype or typedefs.
2022  DeducedType *getContainedDeducedType() const;
2023 
2024  /// Get the AutoType whose type will be deduced for a variable with
2025  /// an initializer of this type. This looks through declarators like pointer
2026  /// types, but not through decltype or typedefs.
2028  return dyn_cast_or_null<AutoType>(getContainedDeducedType());
2029  }
2030 
2031  /// Determine whether this type was written with a leading 'auto'
2032  /// corresponding to a trailing return type (possibly for a nested
2033  /// function type within a pointer to function type or similar).
2034  bool hasAutoForTrailingReturnType() const;
2035 
2036  /// Member-template getAs<specific type>'. Look through sugar for
2037  /// an instance of <specific type>. This scheme will eventually
2038  /// replace the specific getAsXXXX methods above.
2039  ///
2040  /// There are some specializations of this member template listed
2041  /// immediately following this class.
2042  template <typename T> const T *getAs() const;
2043 
2044  /// Member-template getAsAdjusted<specific type>. Look through specific kinds
2045  /// of sugar (parens, attributes, etc) for an instance of <specific type>.
2046  /// This is used when you need to walk over sugar nodes that represent some
2047  /// kind of type adjustment from a type that was written as a <specific type>
2048  /// to another type that is still canonically a <specific type>.
2049  template <typename T> const T *getAsAdjusted() const;
2050 
2051  /// A variant of getAs<> for array types which silently discards
2052  /// qualifiers from the outermost type.
2053  const ArrayType *getAsArrayTypeUnsafe() const;
2054 
2055  /// Member-template castAs<specific type>. Look through sugar for
2056  /// the underlying instance of <specific type>.
2057  ///
2058  /// This method has the same relationship to getAs<T> as cast<T> has
2059  /// to dyn_cast<T>; which is to say, the underlying type *must*
2060  /// have the intended type, and this method will never return null.
2061  template <typename T> const T *castAs() const;
2062 
2063  /// A variant of castAs<> for array type which silently discards
2064  /// qualifiers from the outermost type.
2065  const ArrayType *castAsArrayTypeUnsafe() const;
2066 
2067  /// Get the base element type of this type, potentially discarding type
2068  /// qualifiers. This should never be used when type qualifiers
2069  /// are meaningful.
2070  const Type *getBaseElementTypeUnsafe() const;
2071 
2072  /// If this is an array type, return the element type of the array,
2073  /// potentially with type qualifiers missing.
2074  /// This should never be used when type qualifiers are meaningful.
2075  const Type *getArrayElementTypeNoTypeQual() const;
2076 
2077  /// If this is a pointer type, return the pointee type.
2078  /// If this is an array type, return the array element type.
2079  /// This should never be used when type qualifiers are meaningful.
2080  const Type *getPointeeOrArrayElementType() const;
2081 
2082  /// If this is a pointer, ObjC object pointer, or block
2083  /// pointer, this returns the respective pointee.
2084  QualType getPointeeType() const;
2085 
2086  /// Return the specified type with any "sugar" removed from the type,
2087  /// removing any typedefs, typeofs, etc., as well as any qualifiers.
2088  const Type *getUnqualifiedDesugaredType() const;
2089 
2090  /// More type predicates useful for type checking/promotion
2091  bool isPromotableIntegerType() const; // C99 6.3.1.1p2
2092 
2093  /// Return true if this is an integer type that is
2094  /// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
2095  /// or an enum decl which has a signed representation.
2096  bool isSignedIntegerType() const;
2097 
2098  /// Return true if this is an integer type that is
2099  /// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
2100  /// or an enum decl which has an unsigned representation.
2101  bool isUnsignedIntegerType() const;
2102 
2103  /// Determines whether this is an integer type that is signed or an
2104  /// enumeration types whose underlying type is a signed integer type.
2105  bool isSignedIntegerOrEnumerationType() const;
2106 
2107  /// Determines whether this is an integer type that is unsigned or an
2108  /// enumeration types whose underlying type is a unsigned integer type.
2109  bool isUnsignedIntegerOrEnumerationType() const;
2110 
2111  /// Return true if this is a fixed point type according to
2112  /// ISO/IEC JTC1 SC22 WG14 N1169.
2113  bool isFixedPointType() const;
2114 
2115  /// Return true if this is a saturated fixed point type according to
2116  /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2117  bool isSaturatedFixedPointType() const;
2118 
2119  /// Return true if this is a saturated fixed point type according to
2120  /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2121  bool isUnsaturatedFixedPointType() const;
2122 
2123  /// Return true if this is a fixed point type that is signed according
2124  /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2125  bool isSignedFixedPointType() const;
2126 
2127  /// Return true if this is a fixed point type that is unsigned according
2128  /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2129  bool isUnsignedFixedPointType() const;
2130 
2131  /// Return true if this is not a variable sized type,
2132  /// according to the rules of C99 6.7.5p3. It is not legal to call this on
2133  /// incomplete types.
2134  bool isConstantSizeType() const;
2135 
2136  /// Returns true if this type can be represented by some
2137  /// set of type specifiers.
2138  bool isSpecifierType() const;
2139 
2140  /// Determine the linkage of this type.
2141  Linkage getLinkage() const;
2142 
2143  /// Determine the visibility of this type.
2145  return getLinkageAndVisibility().getVisibility();
2146  }
2147 
2148  /// Return true if the visibility was explicitly set is the code.
2149  bool isVisibilityExplicit() const {
2150  return getLinkageAndVisibility().isVisibilityExplicit();
2151  }
2152 
2153  /// Determine the linkage and visibility of this type.
2154  LinkageInfo getLinkageAndVisibility() const;
2155 
2156  /// True if the computed linkage is valid. Used for consistency
2157  /// checking. Should always return true.
2158  bool isLinkageValid() const;
2159 
2160  /// Determine the nullability of the given type.
2161  ///
2162  /// Note that nullability is only captured as sugar within the type
2163  /// system, not as part of the canonical type, so nullability will
2164  /// be lost by canonicalization and desugaring.
2165  Optional<NullabilityKind> getNullability(const ASTContext &context) const;
2166 
2167  /// Determine whether the given type can have a nullability
2168  /// specifier applied to it, i.e., if it is any kind of pointer type.
2169  ///
2170  /// \param ResultIfUnknown The value to return if we don't yet know whether
2171  /// this type can have nullability because it is dependent.
2172  bool canHaveNullability(bool ResultIfUnknown = true) const;
2173 
2174  /// Retrieve the set of substitutions required when accessing a member
2175  /// of the Objective-C receiver type that is declared in the given context.
2176  ///
2177  /// \c *this is the type of the object we're operating on, e.g., the
2178  /// receiver for a message send or the base of a property access, and is
2179  /// expected to be of some object or object pointer type.
2180  ///
2181  /// \param dc The declaration context for which we are building up a
2182  /// substitution mapping, which should be an Objective-C class, extension,
2183  /// category, or method within.
2184  ///
2185  /// \returns an array of type arguments that can be substituted for
2186  /// the type parameters of the given declaration context in any type described
2187  /// within that context, or an empty optional to indicate that no
2188  /// substitution is required.
2190  getObjCSubstitutions(const DeclContext *dc) const;
2191 
2192  /// Determines if this is an ObjC interface type that may accept type
2193  /// parameters.
2194  bool acceptsObjCTypeParams() const;
2195 
2196  const char *getTypeClassName() const;
2197 
2199  return CanonicalType;
2200  }
2201 
2202  CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
2203  void dump() const;
2204  void dump(llvm::raw_ostream &OS) const;
2205 };
2206 
2207 /// This will check for a TypedefType by removing any existing sugar
2208 /// until it reaches a TypedefType or a non-sugared type.
2209 template <> const TypedefType *Type::getAs() const;
2210 
2211 /// This will check for a TemplateSpecializationType by removing any
2212 /// existing sugar until it reaches a TemplateSpecializationType or a
2213 /// non-sugared type.
2214 template <> const TemplateSpecializationType *Type::getAs() const;
2215 
2216 /// This will check for an AttributedType by removing any existing sugar
2217 /// until it reaches an AttributedType or a non-sugared type.
2218 template <> const AttributedType *Type::getAs() const;
2219 
2220 // We can do canonical leaf types faster, because we don't have to
2221 // worry about preserving child type decoration.
2222 #define TYPE(Class, Base)
2223 #define LEAF_TYPE(Class) \
2224 template <> inline const Class##Type *Type::getAs() const { \
2225  return dyn_cast<Class##Type>(CanonicalType); \
2226 } \
2227 template <> inline const Class##Type *Type::castAs() const { \
2228  return cast<Class##Type>(CanonicalType); \
2229 }
2230 #include "clang/AST/TypeNodes.def"
2231 
2232 /// This class is used for builtin types like 'int'. Builtin
2233 /// types are always canonical and have a literal name field.
2234 class BuiltinType : public Type {
2235 public:
2236  enum Kind {
2237 // OpenCL image types
2238 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2239 #include "clang/Basic/OpenCLImageTypes.def"
2240 // All other builtin types
2241 #define BUILTIN_TYPE(Id, SingletonId) Id,
2242 #define LAST_BUILTIN_TYPE(Id) LastKind = Id
2243 #include "clang/AST/BuiltinTypes.def"
2244  };
2245 
2246 public:
2248  : Type(Builtin, QualType(), /*Dependent=*/(K == Dependent),
2249  /*InstantiationDependent=*/(K == Dependent),
2250  /*VariablyModified=*/false,
2251  /*Unexpanded parameter pack=*/false) {
2252  BuiltinTypeBits.Kind = K;
2253  }
2254 
2255  Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
2256  StringRef getName(const PrintingPolicy &Policy) const;
2257 
2258  const char *getNameAsCString(const PrintingPolicy &Policy) const {
2259  // The StringRef is null-terminated.
2260  StringRef str = getName(Policy);
2261  assert(!str.empty() && str.data()[str.size()] == '\0');
2262  return str.data();
2263  }
2264 
2265  bool isSugared() const { return false; }
2266  QualType desugar() const { return QualType(this, 0); }
2267 
2268  bool isInteger() const {
2269  return getKind() >= Bool && getKind() <= Int128;
2270  }
2271 
2272  bool isSignedInteger() const {
2273  return getKind() >= Char_S && getKind() <= Int128;
2274  }
2275 
2276  bool isUnsignedInteger() const {
2277  return getKind() >= Bool && getKind() <= UInt128;
2278  }
2279 
2280  bool isFloatingPoint() const {
2281  return getKind() >= Half && getKind() <= Float128;
2282  }
2283 
2284  /// Determines whether the given kind corresponds to a placeholder type.
2285  static bool isPlaceholderTypeKind(Kind K) {
2286  return K >= Overload;
2287  }
2288 
2289  /// Determines whether this type is a placeholder type, i.e. a type
2290  /// which cannot appear in arbitrary positions in a fully-formed
2291  /// expression.
2292  bool isPlaceholderType() const {
2293  return isPlaceholderTypeKind(getKind());
2294  }
2295 
2296  /// Determines whether this type is a placeholder type other than
2297  /// Overload. Most placeholder types require only syntactic
2298  /// information about their context in order to be resolved (e.g.
2299  /// whether it is a call expression), which means they can (and
2300  /// should) be resolved in an earlier "phase" of analysis.
2301  /// Overload expressions sometimes pick up further information
2302  /// from their context, like whether the context expects a
2303  /// specific function-pointer type, and so frequently need
2304  /// special treatment.
2306  return getKind() > Overload;
2307  }
2308 
2309  static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2310 };
2311 
2312 /// Complex values, per C99 6.2.5p11. This supports the C99 complex
2313 /// types (_Complex float etc) as well as the GCC integer complex extensions.
2314 class ComplexType : public Type, public llvm::FoldingSetNode {
2315  friend class ASTContext; // ASTContext creates these.
2316 
2317  QualType ElementType;
2318 
2319  ComplexType(QualType Element, QualType CanonicalPtr)
2320  : Type(Complex, CanonicalPtr, Element->isDependentType(),
2321  Element->isInstantiationDependentType(),
2322  Element->isVariablyModifiedType(),
2323  Element->containsUnexpandedParameterPack()),
2324  ElementType(Element) {}
2325 
2326 public:
2327  QualType getElementType() const { return ElementType; }
2328 
2329  bool isSugared() const { return false; }
2330  QualType desugar() const { return QualType(this, 0); }
2331 
2332  void Profile(llvm::FoldingSetNodeID &ID) {
2333  Profile(ID, getElementType());
2334  }
2335 
2336  static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
2337  ID.AddPointer(Element.getAsOpaquePtr());
2338  }
2339 
2340  static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2341 };
2342 
2343 /// Sugar for parentheses used when specifying types.
2344 class ParenType : public Type, public llvm::FoldingSetNode {
2345  friend class ASTContext; // ASTContext creates these.
2346 
2347  QualType Inner;
2348 
2349  ParenType(QualType InnerType, QualType CanonType)
2350  : Type(Paren, CanonType, InnerType->isDependentType(),
2351  InnerType->isInstantiationDependentType(),
2352  InnerType->isVariablyModifiedType(),
2353  InnerType->containsUnexpandedParameterPack()),
2354  Inner(InnerType) {}
2355 
2356 public:
2357  QualType getInnerType() const { return Inner; }
2358 
2359  bool isSugared() const { return true; }
2360  QualType desugar() const { return getInnerType(); }
2361 
2362  void Profile(llvm::FoldingSetNodeID &ID) {
2363  Profile(ID, getInnerType());
2364  }
2365 
2366  static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
2367  Inner.Profile(ID);
2368  }
2369 
2370  static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2371 };
2372 
2373 /// PointerType - C99 6.7.5.1 - Pointer Declarators.
2374 class PointerType : public Type, public llvm::FoldingSetNode {
2375  friend class ASTContext; // ASTContext creates these.
2376 
2377  QualType PointeeType;
2378 
2379  PointerType(QualType Pointee, QualType CanonicalPtr)
2380  : Type(Pointer, CanonicalPtr, Pointee->isDependentType(),
2381  Pointee->isInstantiationDependentType(),
2382  Pointee->isVariablyModifiedType(),
2383  Pointee->containsUnexpandedParameterPack()),
2384  PointeeType(Pointee) {}
2385 
2386 public:
2387  QualType getPointeeType() const { return PointeeType; }
2388 
2389  /// Returns true if address spaces of pointers overlap.
2390  /// OpenCL v2.0 defines conversion rules for pointers to different
2391  /// address spaces (OpenCLC v2.0 s6.5.5) and notion of overlapping
2392  /// address spaces.
2393  /// CL1.1 or CL1.2:
2394  /// address spaces overlap iff they are they same.
2395  /// CL2.0 adds:
2396  /// __generic overlaps with any address space except for __constant.
2397  bool isAddressSpaceOverlapping(const PointerType &other) const {
2398  Qualifiers thisQuals = PointeeType.getQualifiers();
2399  Qualifiers otherQuals = other.getPointeeType().getQualifiers();
2400  // Address spaces overlap if at least one of them is a superset of another
2401  return thisQuals.isAddressSpaceSupersetOf(otherQuals) ||
2402  otherQuals.isAddressSpaceSupersetOf(thisQuals);
2403  }
2404 
2405  bool isSugared() const { return false; }
2406  QualType desugar() const { return QualType(this, 0); }
2407 
2408  void Profile(llvm::FoldingSetNodeID &ID) {
2409  Profile(ID, getPointeeType());
2410  }
2411 
2412  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2413  ID.AddPointer(Pointee.getAsOpaquePtr());
2414  }
2415 
2416  static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2417 };
2418 
2419 /// Represents a type which was implicitly adjusted by the semantic
2420 /// engine for arbitrary reasons. For example, array and function types can
2421 /// decay, and function types can have their calling conventions adjusted.
2422 class AdjustedType : public Type, public llvm::FoldingSetNode {
2423  QualType OriginalTy;
2424  QualType AdjustedTy;
2425 
2426 protected:
2427  friend class ASTContext; // ASTContext creates these.
2428 
2429  AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
2430  QualType CanonicalPtr)
2431  : Type(TC, CanonicalPtr, OriginalTy->isDependentType(),
2432  OriginalTy->isInstantiationDependentType(),
2433  OriginalTy->isVariablyModifiedType(),
2434  OriginalTy->containsUnexpandedParameterPack()),
2435  OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
2436 
2437 public:
2438  QualType getOriginalType() const { return OriginalTy; }
2439  QualType getAdjustedType() const { return AdjustedTy; }
2440 
2441  bool isSugared() const { return true; }
2442  QualType desugar() const { return AdjustedTy; }
2443 
2444  void Profile(llvm::FoldingSetNodeID &ID) {
2445  Profile(ID, OriginalTy, AdjustedTy);
2446  }
2447 
2448  static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
2449  ID.AddPointer(Orig.getAsOpaquePtr());
2450  ID.AddPointer(New.getAsOpaquePtr());
2451  }
2452 
2453  static bool classof(const Type *T) {
2454  return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
2455  }
2456 };
2457 
2458 /// Represents a pointer type decayed from an array or function type.
2459 class DecayedType : public AdjustedType {
2460  friend class ASTContext; // ASTContext creates these.
2461 
2462  inline
2463  DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);
2464 
2465 public:
2466  QualType getDecayedType() const { return getAdjustedType(); }
2467 
2468  inline QualType getPointeeType() const;
2469 
2470  static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
2471 };
2472 
2473 /// Pointer to a block type.
2474 /// This type is to represent types syntactically represented as
2475 /// "void (^)(int)", etc. Pointee is required to always be a function type.
2476 class BlockPointerType : public Type, public llvm::FoldingSetNode {
2477  friend class ASTContext; // ASTContext creates these.
2478 
2479  // Block is some kind of pointer type
2480  QualType PointeeType;
2481 
2482  BlockPointerType(QualType Pointee, QualType CanonicalCls)
2483  : Type(BlockPointer, CanonicalCls, Pointee->isDependentType(),
2484  Pointee->isInstantiationDependentType(),
2485  Pointee->isVariablyModifiedType(),
2486  Pointee->containsUnexpandedParameterPack()),
2487  PointeeType(Pointee) {}
2488 
2489 public:
2490  // Get the pointee type. Pointee is required to always be a function type.
2491  QualType getPointeeType() const { return PointeeType; }
2492 
2493  bool isSugared() const { return false; }
2494  QualType desugar() const { return QualType(this, 0); }
2495 
2496  void Profile(llvm::FoldingSetNodeID &ID) {
2497  Profile(ID, getPointeeType());
2498  }
2499 
2500  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2501  ID.AddPointer(Pointee.getAsOpaquePtr());
2502  }
2503 
2504  static bool classof(const Type *T) {
2505  return T->getTypeClass() == BlockPointer;
2506  }
2507 };
2508 
2509 /// Base for LValueReferenceType and RValueReferenceType
2510 class ReferenceType : public Type, public llvm::FoldingSetNode {
2511  QualType PointeeType;
2512 
2513 protected:
2514  ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
2515  bool SpelledAsLValue)
2516  : Type(tc, CanonicalRef, Referencee->isDependentType(),
2517  Referencee->isInstantiationDependentType(),
2518  Referencee->isVariablyModifiedType(),
2519  Referencee->containsUnexpandedParameterPack()),
2520  PointeeType(Referencee) {
2521  ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
2522  ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
2523  }
2524 
2525 public:
2526  bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
2527  bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }
2528 
2529  QualType getPointeeTypeAsWritten() const { return PointeeType; }
2530 
2532  // FIXME: this might strip inner qualifiers; okay?
2533  const ReferenceType *T = this;
2534  while (T->isInnerRef())
2535  T = T->PointeeType->castAs<ReferenceType>();
2536  return T->PointeeType;
2537  }
2538 
2539  void Profile(llvm::FoldingSetNodeID &ID) {
2540  Profile(ID, PointeeType, isSpelledAsLValue());
2541  }
2542 
2543  static void Profile(llvm::FoldingSetNodeID &ID,
2544  QualType Referencee,
2545  bool SpelledAsLValue) {
2546  ID.AddPointer(Referencee.getAsOpaquePtr());
2547  ID.AddBoolean(SpelledAsLValue);
2548  }
2549 
2550  static bool classof(const Type *T) {
2551  return T->getTypeClass() == LValueReference ||
2552  T->getTypeClass() == RValueReference;
2553  }
2554 };
2555 
2556 /// An lvalue reference type, per C++11 [dcl.ref].
2558  friend class ASTContext; // ASTContext creates these
2559 
2560  LValueReferenceType(QualType Referencee, QualType CanonicalRef,
2561  bool SpelledAsLValue)
2562  : ReferenceType(LValueReference, Referencee, CanonicalRef,
2563  SpelledAsLValue) {}
2564 
2565 public:
2566  bool isSugared() const { return false; }
2567  QualType desugar() const { return QualType(this, 0); }
2568 
2569  static bool classof(const Type *T) {
2570  return T->getTypeClass() == LValueReference;
2571  }
2572 };
2573 
2574 /// An rvalue reference type, per C++11 [dcl.ref].
2576  friend class ASTContext; // ASTContext creates these
2577 
2578  RValueReferenceType(QualType Referencee, QualType CanonicalRef)
2579  : ReferenceType(RValueReference, Referencee, CanonicalRef, false) {}
2580 
2581 public:
2582  bool isSugared() const { return false; }
2583  QualType desugar() const { return QualType(this, 0); }
2584 
2585  static bool classof(const Type *T) {
2586  return T->getTypeClass() == RValueReference;
2587  }
2588 };
2589 
2590 /// A pointer to member type per C++ 8.3.3 - Pointers to members.
2591 ///
2592 /// This includes both pointers to data members and pointer to member functions.
2593 class MemberPointerType : public Type, public llvm::FoldingSetNode {
2594  friend class ASTContext; // ASTContext creates these.
2595 
2596  QualType PointeeType;
2597 
2598  /// The class of which the pointee is a member. Must ultimately be a
2599  /// RecordType, but could be a typedef or a template parameter too.
2600  const Type *Class;
2601 
2602  MemberPointerType(QualType Pointee, const Type *Cls, QualType CanonicalPtr)
2603  : Type(MemberPointer, CanonicalPtr,
2604  Cls->isDependentType() || Pointee->isDependentType(),
2605  (Cls->isInstantiationDependentType() ||
2606  Pointee->isInstantiationDependentType()),
2607  Pointee->isVariablyModifiedType(),
2608  (Cls->containsUnexpandedParameterPack() ||
2609  Pointee->containsUnexpandedParameterPack())),
2610  PointeeType(Pointee), Class(Cls) {}
2611 
2612 public:
2613  QualType getPointeeType() const { return PointeeType; }
2614 
2615  /// Returns true if the member type (i.e. the pointee type) is a
2616  /// function type rather than a data-member type.
2618  return PointeeType->isFunctionProtoType();
2619  }
2620 
2621  /// Returns true if the member type (i.e. the pointee type) is a
2622  /// data type rather than a function type.
2623  bool isMemberDataPointer() const {
2624  return !PointeeType->isFunctionProtoType();
2625  }
2626 
2627  const Type *getClass() const { return Class; }
2628  CXXRecordDecl *getMostRecentCXXRecordDecl() const;
2629 
2630  bool isSugared() const { return false; }
2631  QualType desugar() const { return QualType(this, 0); }
2632 
2633  void Profile(llvm::FoldingSetNodeID &ID) {
2634  Profile(ID, getPointeeType(), getClass());
2635  }
2636 
2637  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee,
2638  const Type *Class) {
2639  ID.AddPointer(Pointee.getAsOpaquePtr());
2640  ID.AddPointer(Class);
2641  }
2642 
2643  static bool classof(const Type *T) {
2644  return T->getTypeClass() == MemberPointer;
2645  }
2646 };
2647 
2648 /// Represents an array type, per C99 6.7.5.2 - Array Declarators.
2649 class ArrayType : public Type, public llvm::FoldingSetNode {
2650 public:
2651  /// Capture whether this is a normal array (e.g. int X[4])
2652  /// an array with a static size (e.g. int X[static 4]), or an array
2653  /// with a star size (e.g. int X[*]).
2654  /// 'static' is only allowed on function parameters.
2656  Normal, Static, Star
2657  };
2658 
2659 private:
2660  /// The element type of the array.
2661  QualType ElementType;
2662 
2663 protected:
2664  friend class ASTContext; // ASTContext creates these.
2665 
2666  // C++ [temp.dep.type]p1:
2667  // A type is dependent if it is...
2668  // - an array type constructed from any dependent type or whose
2669  // size is specified by a constant expression that is
2670  // value-dependent,
2672  ArraySizeModifier sm, unsigned tq,
2673  bool ContainsUnexpandedParameterPack)
2674  : Type(tc, can, et->isDependentType() || tc == DependentSizedArray,
2675  et->isInstantiationDependentType() || tc == DependentSizedArray,
2676  (tc == VariableArray || et->isVariablyModifiedType()),
2677  ContainsUnexpandedParameterPack),
2678  ElementType(et) {
2679  ArrayTypeBits.IndexTypeQuals = tq;
2680  ArrayTypeBits.SizeModifier = sm;
2681  }
2682 
2683 public:
2684  QualType getElementType() const { return ElementType; }
2685 
2687  return ArraySizeModifier(ArrayTypeBits.SizeModifier);
2688  }
2689 
2691  return Qualifiers::fromCVRMask(getIndexTypeCVRQualifiers());
2692  }
2693 
2694  unsigned getIndexTypeCVRQualifiers() const {
2695  return ArrayTypeBits.IndexTypeQuals;
2696  }
2697 
2698  static bool classof(const Type *T) {
2699  return T->getTypeClass() == ConstantArray ||
2700  T->getTypeClass() == VariableArray ||
2701  T->getTypeClass() == IncompleteArray ||
2702  T->getTypeClass() == DependentSizedArray;
2703  }
2704 };
2705 
2706 /// Represents the canonical version of C arrays with a specified constant size.
2707 /// For example, the canonical type for 'int A[4 + 4*100]' is a
2708 /// ConstantArrayType where the element type is 'int' and the size is 404.
2710  llvm::APInt Size; // Allows us to unique the type.
2711 
2712  ConstantArrayType(QualType et, QualType can, const llvm::APInt &size,
2713  ArraySizeModifier sm, unsigned tq)
2714  : ArrayType(ConstantArray, et, can, sm, tq,
2716  Size(size) {}
2717 
2718 protected:
2719  friend class ASTContext; // ASTContext creates these.
2720 
2722  const llvm::APInt &size, ArraySizeModifier sm, unsigned tq)
2723  : ArrayType(tc, et, can, sm, tq, et->containsUnexpandedParameterPack()),
2724  Size(size) {}
2725 
2726 public:
2727  const llvm::APInt &getSize() const { return Size; }
2728  bool isSugared() const { return false; }
2729  QualType desugar() const { return QualType(this, 0); }
2730 
2731  /// Determine the number of bits required to address a member of
2732  // an array with the given element type and number of elements.
2733  static unsigned getNumAddressingBits(const ASTContext &Context,
2734  QualType ElementType,
2735  const llvm::APInt &NumElements);
2736 
2737  /// Determine the maximum number of active bits that an array's size
2738  /// can require, which limits the maximum size of the array.
2739  static unsigned getMaxSizeBits(const ASTContext &Context);
2740 
2741  void Profile(llvm::FoldingSetNodeID &ID) {
2742  Profile(ID, getElementType(), getSize(),
2743  getSizeModifier(), getIndexTypeCVRQualifiers());
2744  }
2745 
2746  static void Profile(llvm::FoldingSetNodeID &ID, QualType ET,
2747  const llvm::APInt &ArraySize, ArraySizeModifier SizeMod,
2748  unsigned TypeQuals) {
2749  ID.AddPointer(ET.getAsOpaquePtr());
2750  ID.AddInteger(ArraySize.getZExtValue());
2751  ID.AddInteger(SizeMod);
2752  ID.AddInteger(TypeQuals);
2753  }
2754 
2755  static bool classof(const Type *T) {
2756  return T->getTypeClass() == ConstantArray;
2757  }
2758 };
2759 
2760 /// Represents a C array with an unspecified size. For example 'int A[]' has
2761 /// an IncompleteArrayType where the element type is 'int' and the size is
2762 /// unspecified.
2764  friend class ASTContext; // ASTContext creates these.
2765 
2767  ArraySizeModifier sm, unsigned tq)
2768  : ArrayType(IncompleteArray, et, can, sm, tq,
2769  et->containsUnexpandedParameterPack()) {}
2770 
2771 public:
2772  friend class StmtIteratorBase;
2773 
2774  bool isSugared() const { return false; }
2775  QualType desugar() const { return QualType(this, 0); }
2776 
2777  static bool classof(const Type *T) {
2778  return T->getTypeClass() == IncompleteArray;
2779  }
2780 
2781  void Profile(llvm::FoldingSetNodeID &ID) {
2782  Profile(ID, getElementType(), getSizeModifier(),
2783  getIndexTypeCVRQualifiers());
2784  }
2785 
2786  static void Profile(llvm::FoldingSetNodeID &ID, QualType ET,
2787  ArraySizeModifier SizeMod, unsigned TypeQuals) {
2788  ID.AddPointer(ET.getAsOpaquePtr());
2789  ID.AddInteger(SizeMod);
2790  ID.AddInteger(TypeQuals);
2791  }
2792 };
2793 
2794 /// Represents a C array with a specified size that is not an
2795 /// integer-constant-expression. For example, 'int s[x+foo()]'.
2796 /// Since the size expression is an arbitrary expression, we store it as such.
2797 ///
2798 /// Note: VariableArrayType's aren't uniqued (since the expressions aren't) and
2799 /// should not be: two lexically equivalent variable array types could mean
2800 /// different things, for example, these variables do not have the same type
2801 /// dynamically:
2802 ///
2803 /// void foo(int x) {
2804 /// int Y[x];
2805 /// ++x;
2806 /// int Z[x];
2807 /// }
2809  friend class ASTContext; // ASTContext creates these.
2810 
2811  /// An assignment-expression. VLA's are only permitted within
2812  /// a function block.
2813  Stmt *SizeExpr;
2814 
2815  /// The range spanned by the left and right array brackets.
2816  SourceRange Brackets;
2817 
2819  ArraySizeModifier sm, unsigned tq,
2820  SourceRange brackets)
2821  : ArrayType(VariableArray, et, can, sm, tq,
2822  et->containsUnexpandedParameterPack()),
2823  SizeExpr((Stmt*) e), Brackets(brackets) {}
2824 
2825 public:
2826  friend class StmtIteratorBase;
2827 
2828  Expr *getSizeExpr() const {
2829  // We use C-style casts instead of cast<> here because we do not wish
2830  // to have a dependency of Type.h on Stmt.h/Expr.h.
2831  return (Expr*) SizeExpr;
2832  }
2833 
2834  SourceRange getBracketsRange() const { return Brackets; }
2835  SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
2836  SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
2837 
2838  bool isSugared() const { return false; }
2839  QualType desugar() const { return QualType(this, 0); }
2840 
2841  static bool classof(const Type *T) {
2842  return T->getTypeClass() == VariableArray;
2843  }
2844 
2845  void Profile(llvm::FoldingSetNodeID &ID) {
2846  llvm_unreachable("Cannot unique VariableArrayTypes.");
2847  }
2848 };
2849 
2850 /// Represents an array type in C++ whose size is a value-dependent expression.
2851 ///
2852 /// For example:
2853 /// \code
2854 /// template<typename T, int Size>
2855 /// class array {
2856 /// T data[Size];
2857 /// };
2858 /// \endcode
2859 ///
2860 /// For these types, we won't actually know what the array bound is
2861 /// until template instantiation occurs, at which point this will
2862 /// become either a ConstantArrayType or a VariableArrayType.
2864  friend class ASTContext; // ASTContext creates these.
2865 
2866  const ASTContext &Context;
2867 
2868  /// An assignment expression that will instantiate to the
2869  /// size of the array.
2870  ///
2871  /// The expression itself might be null, in which case the array
2872  /// type will have its size deduced from an initializer.
2873  Stmt *SizeExpr;
2874 
2875  /// The range spanned by the left and right array brackets.
2876  SourceRange Brackets;
2877 
2878  DependentSizedArrayType(const ASTContext &Context, QualType et, QualType can,
2879  Expr *e, ArraySizeModifier sm, unsigned tq,
2880  SourceRange brackets);
2881 
2882 public:
2883  friend class StmtIteratorBase;
2884 
2885  Expr *getSizeExpr() const {
2886  // We use C-style casts instead of cast<> here because we do not wish
2887  // to have a dependency of Type.h on Stmt.h/Expr.h.
2888  return (Expr*) SizeExpr;
2889  }
2890 
2891  SourceRange getBracketsRange() const { return Brackets; }
2892  SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
2893  SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }
2894 
2895  bool isSugared() const { return false; }
2896  QualType desugar() const { return QualType(this, 0); }
2897 
2898  static bool classof(const Type *T) {
2899  return T->getTypeClass() == DependentSizedArray;
2900  }
2901 
2902  void Profile(llvm::FoldingSetNodeID &ID) {
2903  Profile(ID, Context, getElementType(),
2904  getSizeModifier(), getIndexTypeCVRQualifiers(), getSizeExpr());
2905  }
2906 
2907  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
2908  QualType ET, ArraySizeModifier SizeMod,
2909  unsigned TypeQuals, Expr *E);
2910 };
2911 
2912 /// Represents an extended address space qualifier where the input address space
2913 /// value is dependent. Non-dependent address spaces are not represented with a
2914 /// special Type subclass; they are stored on an ExtQuals node as part of a QualType.
2915 ///
2916 /// For example:
2917 /// \code
2918 /// template<typename T, int AddrSpace>
2919 /// class AddressSpace {
2920 /// typedef T __attribute__((address_space(AddrSpace))) type;
2921 /// }
2922 /// \endcode
2923 class DependentAddressSpaceType : public Type, public llvm::FoldingSetNode {
2924  friend class ASTContext;
2925 
2926  const ASTContext &Context;
2927  Expr *AddrSpaceExpr;
2928  QualType PointeeType;
2929  SourceLocation loc;
2930 
2931  DependentAddressSpaceType(const ASTContext &Context, QualType PointeeType,
2932  QualType can, Expr *AddrSpaceExpr,
2933  SourceLocation loc);
2934 
2935 public:
2936  Expr *getAddrSpaceExpr() const { return AddrSpaceExpr; }
2937  QualType getPointeeType() const { return PointeeType; }
2938  SourceLocation getAttributeLoc() const { return loc; }
2939 
2940  bool isSugared() const { return false; }
2941  QualType desugar() const { return QualType(this, 0); }
2942 
2943  static bool classof(const Type *T) {
2944  return T->getTypeClass() == DependentAddressSpace;
2945  }
2946 
2947  void Profile(llvm::FoldingSetNodeID &ID) {
2948  Profile(ID, Context, getPointeeType(), getAddrSpaceExpr());
2949  }
2950 
2951  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
2952  QualType PointeeType, Expr *AddrSpaceExpr);
2953 };
2954 
2955 /// Represents an extended vector type where either the type or size is
2956 /// dependent.
2957 ///
2958 /// For example:
2959 /// \code
2960 /// template<typename T, int Size>
2961 /// class vector {
2962 /// typedef T __attribute__((ext_vector_type(Size))) type;
2963 /// }
2964 /// \endcode
2965 class DependentSizedExtVectorType : public Type, public llvm::FoldingSetNode {
2966  friend class ASTContext;
2967 
2968  const ASTContext &Context;
2969  Expr *SizeExpr;
2970 
2971  /// The element type of the array.
2972  QualType ElementType;
2973 
2974  SourceLocation loc;
2975 
2976  DependentSizedExtVectorType(const ASTContext &Context, QualType ElementType,
2977  QualType can, Expr *SizeExpr, SourceLocation loc);
2978 
2979 public:
2980  Expr *getSizeExpr() const { return SizeExpr; }
2981  QualType getElementType() const { return ElementType; }
2982  SourceLocation getAttributeLoc() const { return loc; }
2983 
2984  bool isSugared() const { return false; }
2985  QualType desugar() const { return QualType(this, 0); }
2986 
2987  static bool classof(const Type *T) {
2988  return T->getTypeClass() == DependentSizedExtVector;
2989  }
2990 
2991  void Profile(llvm::FoldingSetNodeID &ID) {
2992  Profile(ID, Context, getElementType(), getSizeExpr());
2993  }
2994 
2995  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
2996  QualType ElementType, Expr *SizeExpr);
2997 };
2998 
2999 
3000 /// Represents a GCC generic vector type. This type is created using
3001 /// __attribute__((vector_size(n)), where "n" specifies the vector size in
3002 /// bytes; or from an Altivec __vector or vector declaration.
3003 /// Since the constructor takes the number of vector elements, the
3004 /// client is responsible for converting the size into the number of elements.
3005 class VectorType : public Type, public llvm::FoldingSetNode {
3006 public:
3007  enum VectorKind {
3008  /// not a target-specific vector type
3010 
3011  /// is AltiVec vector
3013 
3014  /// is AltiVec 'vector Pixel'
3016 
3017  /// is AltiVec 'vector bool ...'
3019 
3020  /// is ARM Neon vector
3022 
3023  /// is ARM Neon polynomial vector
3024  NeonPolyVector
3025  };
3026 
3027 protected:
3028  friend class ASTContext; // ASTContext creates these.
3029 
3030  /// The element type of the vector.
3032 
3033  VectorType(QualType vecType, unsigned nElements, QualType canonType,
3034  VectorKind vecKind);
3035 
3036  VectorType(TypeClass tc, QualType vecType, unsigned nElements,
3037  QualType canonType, VectorKind vecKind);
3038 
3039 public:
3040  QualType getElementType() const { return ElementType; }
3041  unsigned getNumElements() const { return VectorTypeBits.NumElements; }
3042 
3043  static bool isVectorSizeTooLarge(unsigned NumElements) {
3044  return NumElements > VectorTypeBitfields::MaxNumElements;
3045  }
3046 
3047  bool isSugared() const { return false; }
3048  QualType desugar() const { return QualType(this, 0); }
3049 
3051  return VectorKind(VectorTypeBits.VecKind);
3052  }
3053 
3054  void Profile(llvm::FoldingSetNodeID &ID) {
3055  Profile(ID, getElementType(), getNumElements(),
3056  getTypeClass(), getVectorKind());
3057  }
3058 
3059  static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
3060  unsigned NumElements, TypeClass TypeClass,
3061  VectorKind VecKind) {
3062  ID.AddPointer(ElementType.getAsOpaquePtr());
3063  ID.AddInteger(NumElements);
3064  ID.AddInteger(TypeClass);
3065  ID.AddInteger(VecKind);
3066  }
3067 
3068  static bool classof(const Type *T) {
3069  return T->getTypeClass() == Vector || T->getTypeClass() == ExtVector;
3070  }
3071 };
3072 
3073 /// ExtVectorType - Extended vector type. This type is created using
3074 /// __attribute__((ext_vector_type(n)), where "n" is the number of elements.
3075 /// Unlike vector_size, ext_vector_type is only allowed on typedef's. This
3076 /// class enables syntactic extensions, like Vector Components for accessing
3077 /// points (as .xyzw), colors (as .rgba), and textures (modeled after OpenGL
3078 /// Shading Language).
3079 class ExtVectorType : public VectorType {
3080  friend class ASTContext; // ASTContext creates these.
3081 
3082  ExtVectorType(QualType vecType, unsigned nElements, QualType canonType)
3083  : VectorType(ExtVector, vecType, nElements, canonType, GenericVector) {}
3084 
3085 public:
3086  static int getPointAccessorIdx(char c) {
3087  switch (c) {
3088  default: return -1;
3089  case 'x': case 'r': return 0;
3090  case 'y': case 'g': return 1;
3091  case 'z': case 'b': return 2;
3092  case 'w': case 'a': return 3;
3093  }
3094  }
3095 
3096  static int getNumericAccessorIdx(char c) {
3097  switch (c) {
3098  default: return -1;
3099  case '0': return 0;
3100  case '1': return 1;
3101  case '2': return 2;
3102  case '3': return 3;
3103  case '4': return 4;
3104  case '5': return 5;
3105  case '6': return 6;
3106  case '7': return 7;
3107  case '8': return 8;
3108  case '9': return 9;
3109  case 'A':
3110  case 'a': return 10;
3111  case 'B':
3112  case 'b': return 11;
3113  case 'C':
3114  case 'c': return 12;
3115  case 'D':
3116  case 'd': return 13;
3117  case 'E':
3118  case 'e': return 14;
3119  case 'F':
3120  case 'f': return 15;
3121  }
3122  }
3123 
3124  static int getAccessorIdx(char c, bool isNumericAccessor) {
3125  if (isNumericAccessor)
3126  return getNumericAccessorIdx(c);
3127  else
3128  return getPointAccessorIdx(c);
3129  }
3130 
3131  bool isAccessorWithinNumElements(char c, bool isNumericAccessor) const {
3132  if (int idx = getAccessorIdx(c, isNumericAccessor)+1)
3133  return unsigned(idx-1) < getNumElements();
3134  return false;
3135  }
3136 
3137  bool isSugared() const { return false; }
3138  QualType desugar() const { return QualType(this, 0); }
3139 
3140  static bool classof(const Type *T) {
3141  return T->getTypeClass() == ExtVector;
3142  }
3143 };
3144 
3145 /// FunctionType - C99 6.7.5.3 - Function Declarators. This is the common base
3146 /// class of FunctionNoProtoType and FunctionProtoType.
3147 class FunctionType : public Type {
3148  // The type returned by the function.
3149  QualType ResultType;
3150 
3151 public:
3152  /// A class which abstracts out some details necessary for
3153  /// making a call.
3154  ///
3155  /// It is not actually used directly for storing this information in
3156  /// a FunctionType, although FunctionType does currently use the
3157  /// same bit-pattern.
3158  ///
3159  // If you add a field (say Foo), other than the obvious places (both,
3160  // constructors, compile failures), what you need to update is
3161  // * Operator==
3162  // * getFoo
3163  // * withFoo
3164  // * functionType. Add Foo, getFoo.
3165  // * ASTContext::getFooType
3166  // * ASTContext::mergeFunctionTypes
3167  // * FunctionNoProtoType::Profile
3168  // * FunctionProtoType::Profile
3169  // * TypePrinter::PrintFunctionProto
3170  // * AST read and write
3171  // * Codegen
3172  class ExtInfo {
3173  friend class FunctionType;
3174 
3175  // Feel free to rearrange or add bits, but if you go over 12,
3176  // you'll need to adjust both the Bits field below and
3177  // Type::FunctionTypeBitfields.
3178 
3179  // | CC |noreturn|produces|nocallersavedregs|regparm|nocfcheck|
3180  // |0 .. 4| 5 | 6 | 7 |8 .. 10| 11 |
3181  //
3182  // regparm is either 0 (no regparm attribute) or the regparm value+1.
3183  enum { CallConvMask = 0x1F };
3184  enum { NoReturnMask = 0x20 };
3185  enum { ProducesResultMask = 0x40 };
3186  enum { NoCallerSavedRegsMask = 0x80 };
3187  enum { NoCfCheckMask = 0x800 };
3188  enum {
3189  RegParmMask = ~(CallConvMask | NoReturnMask | ProducesResultMask |
3190  NoCallerSavedRegsMask | NoCfCheckMask),
3191  RegParmOffset = 8
3192  }; // Assumed to be the last field
3193  uint16_t Bits = CC_C;
3194 
3195  ExtInfo(unsigned Bits) : Bits(static_cast<uint16_t>(Bits)) {}
3196 
3197  public:
3198  // Constructor with no defaults. Use this when you know that you
3199  // have all the elements (when reading an AST file for example).
3200  ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
3201  bool producesResult, bool noCallerSavedRegs, bool NoCfCheck) {
3202  assert((!hasRegParm || regParm < 7) && "Invalid regparm value");
3203  Bits = ((unsigned)cc) | (noReturn ? NoReturnMask : 0) |
3204  (producesResult ? ProducesResultMask : 0) |
3205  (noCallerSavedRegs ? NoCallerSavedRegsMask : 0) |
3206  (hasRegParm ? ((regParm + 1) << RegParmOffset) : 0) |
3207  (NoCfCheck ? NoCfCheckMask : 0);
3208  }
3209 
3210  // Constructor with all defaults. Use when for example creating a
3211  // function known to use defaults.
3212  ExtInfo() = default;
3213 
3214  // Constructor with just the calling convention, which is an important part
3215  // of the canonical type.
3216  ExtInfo(CallingConv CC) : Bits(CC) {}
3217 
3218  bool getNoReturn() const { return Bits & NoReturnMask; }
3219  bool getProducesResult() const { return Bits & ProducesResultMask; }
3220  bool getNoCallerSavedRegs() const { return Bits & NoCallerSavedRegsMask; }
3221  bool getNoCfCheck() const { return Bits & NoCfCheckMask; }
3222  bool getHasRegParm() const { return (Bits >> RegParmOffset) != 0; }
3223 
3224  unsigned getRegParm() const {
3225  unsigned RegParm = (Bits & RegParmMask) >> RegParmOffset;
3226  if (RegParm > 0)
3227  --RegParm;
3228  return RegParm;
3229  }
3230 
3231  CallingConv getCC() const { return CallingConv(Bits & CallConvMask); }
3232 
3233  bool operator==(ExtInfo Other) const {
3234  return Bits == Other.Bits;
3235  }
3236  bool operator!=(ExtInfo Other) const {
3237  return Bits != Other.Bits;
3238  }
3239 
3240  // Note that we don't have setters. That is by design, use
3241  // the following with methods instead of mutating these objects.
3242 
3243  ExtInfo withNoReturn(bool noReturn) const {
3244  if (noReturn)
3245  return ExtInfo(Bits | NoReturnMask);
3246  else
3247  return ExtInfo(Bits & ~NoReturnMask);
3248  }
3249 
3250  ExtInfo withProducesResult(bool producesResult) const {
3251  if (producesResult)
3252  return ExtInfo(Bits | ProducesResultMask);
3253  else
3254  return ExtInfo(Bits & ~ProducesResultMask);
3255  }
3256 
3257  ExtInfo withNoCallerSavedRegs(bool noCallerSavedRegs) const {
3258  if (noCallerSavedRegs)
3259  return ExtInfo(Bits | NoCallerSavedRegsMask);
3260  else
3261  return ExtInfo(Bits & ~NoCallerSavedRegsMask);
3262  }
3263 
3264  ExtInfo withNoCfCheck(bool noCfCheck) const {
3265  if (noCfCheck)
3266  return ExtInfo(Bits | NoCfCheckMask);
3267  else
3268  return ExtInfo(Bits & ~NoCfCheckMask);
3269  }
3270 
3271  ExtInfo withRegParm(unsigned RegParm) const {
3272  assert(RegParm < 7 && "Invalid regparm value");
3273  return ExtInfo((Bits & ~RegParmMask) |
3274  ((RegParm + 1) << RegParmOffset));
3275  }
3276 
3278  return ExtInfo((Bits & ~CallConvMask) | (unsigned) cc);
3279  }
3280 
3281  void Profile(llvm::FoldingSetNodeID &ID) const {
3282  ID.AddInteger(Bits);
3283  }
3284  };
3285 
3286 protected:
3288  QualType Canonical, bool Dependent,
3289  bool InstantiationDependent,
3290  bool VariablyModified, bool ContainsUnexpandedParameterPack,
3291  ExtInfo Info)
3292  : Type(tc, Canonical, Dependent, InstantiationDependent, VariablyModified,
3293  ContainsUnexpandedParameterPack),
3294  ResultType(res) {
3295  FunctionTypeBits.ExtInfo = Info.Bits;
3296  }
3297 
3298  unsigned getTypeQuals() const { return FunctionTypeBits.TypeQuals; }
3299 
3300 public:
3301  QualType getReturnType() const { return ResultType; }
3302 
3303  bool getHasRegParm() const { return getExtInfo().getHasRegParm(); }
3304  unsigned getRegParmType() const { return getExtInfo().getRegParm(); }
3305 
3306  /// Determine whether this function type includes the GNU noreturn
3307  /// attribute. The C++11 [[noreturn]] attribute does not affect the function
3308  /// type.
3309  bool getNoReturnAttr() const { return getExtInfo().getNoReturn(); }
3310 
3311  CallingConv getCallConv() const { return getExtInfo().getCC(); }
3312  ExtInfo getExtInfo() const { return ExtInfo(FunctionTypeBits.ExtInfo); }
3313  bool isConst() const { return getTypeQuals() & Qualifiers::Const; }
3314  bool isVolatile() const { return getTypeQuals() & Qualifiers::Volatile; }
3315  bool isRestrict() const { return getTypeQuals() & Qualifiers::Restrict; }
3316 
3317  /// Determine the type of an expression that calls a function of
3318  /// this type.
3319  QualType getCallResultType(const ASTContext &Context) const {
3320  return getReturnType().getNonLValueExprType(Context);
3321  }
3322 
3323  static StringRef getNameForCallConv(CallingConv CC);
3324 
3325  static bool classof(const Type *T) {
3326  return T->getTypeClass() == FunctionNoProto ||
3327  T->getTypeClass() == FunctionProto;
3328  }
3329 };
3330 
3331 /// Represents a K&R-style 'int foo()' function, which has
3332 /// no information available about its arguments.
3333 class FunctionNoProtoType : public FunctionType, public llvm::FoldingSetNode {
3334  friend class ASTContext; // ASTContext creates these.
3335 
3337  : FunctionType(FunctionNoProto, Result, Canonical,
3338  /*Dependent=*/false, /*InstantiationDependent=*/false,
3339  Result->isVariablyModifiedType(),
3340  /*ContainsUnexpandedParameterPack=*/false, Info) {}
3341 
3342 public:
3343  // No additional state past what FunctionType provides.
3344 
3345  bool isSugared() const { return false; }
3346  QualType desugar() const { return QualType(this, 0); }
3347 
3348  void Profile(llvm::FoldingSetNodeID &ID) {
3349  Profile(ID, getReturnType(), getExtInfo());
3350  }
3351 
3352  static void Profile(llvm::FoldingSetNodeID &ID, QualType ResultType,
3353  ExtInfo Info) {
3354  Info.Profile(ID);
3355  ID.AddPointer(ResultType.getAsOpaquePtr());
3356  }
3357 
3358  static bool classof(const Type *T) {
3359  return T->getTypeClass() == FunctionNoProto;
3360  }
3361 };
3362 
3363 /// Represents a prototype with parameter type info, e.g.
3364 /// 'int foo(int)' or 'int foo(void)'. 'void' is represented as having no
3365 /// parameters, not as having a single void parameter. Such a type can have an
3366 /// exception specification, but this specification is not part of the canonical
3367 /// type.
3368 class FunctionProtoType : public FunctionType, public llvm::FoldingSetNode {
3369 public:
3370  /// Interesting information about a specific parameter that can't simply
3371  /// be reflected in parameter's type.
3372  ///
3373  /// It makes sense to model language features this way when there's some
3374  /// sort of parameter-specific override (such as an attribute) that
3375  /// affects how the function is called. For example, the ARC ns_consumed
3376  /// attribute changes whether a parameter is passed at +0 (the default)
3377  /// or +1 (ns_consumed). This must be reflected in the function type,
3378  /// but isn't really a change to the parameter type.
3379  ///
3380  /// One serious disadvantage of modelling language features this way is
3381  /// that they generally do not work with language features that attempt
3382  /// to destructure types. For example, template argument deduction will
3383  /// not be able to match a parameter declared as
3384  /// T (*)(U)
3385  /// against an argument of type
3386  /// void (*)(__attribute__((ns_consumed)) id)
3387  /// because the substitution of T=void, U=id into the former will
3388  /// not produce the latter.
3390  enum {
3391  ABIMask = 0x0F,
3392  IsConsumed = 0x10,
3393  HasPassObjSize = 0x20,
3394  IsNoEscape = 0x40,
3395  };
3396  unsigned char Data = 0;
3397 
3398  public:
3399  ExtParameterInfo() = default;
3400 
3401  /// Return the ABI treatment of this parameter.
3403  return ParameterABI(Data & ABIMask);
3404  }
3406  ExtParameterInfo copy = *this;
3407  copy.Data = (copy.Data & ~ABIMask) | unsigned(kind);
3408  return copy;
3409  }
3410 
3411  /// Is this parameter considered "consumed" by Objective-C ARC?
3412  /// Consumed parameters must have retainable object type.
3413  bool isConsumed() const {
3414  return (Data & IsConsumed);
3415  }
3416  ExtParameterInfo withIsConsumed(bool consumed) const {
3417  ExtParameterInfo copy = *this;
3418  if (consumed) {
3419  copy.Data |= IsConsumed;
3420  } else {
3421  copy.Data &= ~IsConsumed;
3422  }
3423  return copy;
3424  }
3425 
3426  bool hasPassObjectSize() const {
3427  return Data & HasPassObjSize;
3428  }
3430  ExtParameterInfo Copy = *this;
3431  Copy.Data |= HasPassObjSize;
3432  return Copy;
3433  }
3434 
3435  bool isNoEscape() const {
3436  return Data & IsNoEscape;
3437  }
3438 
3439  ExtParameterInfo withIsNoEscape(bool NoEscape) const {
3440  ExtParameterInfo Copy = *this;
3441  if (NoEscape)
3442  Copy.Data |= IsNoEscape;
3443  else
3444  Copy.Data &= ~IsNoEscape;
3445  return Copy;
3446  }
3447 
3448  unsigned char getOpaqueValue() const { return Data; }
3449  static ExtParameterInfo getFromOpaqueValue(unsigned char data) {
3450  ExtParameterInfo result;
3451  result.Data = data;
3452  return result;
3453  }
3454 
3456  return lhs.Data == rhs.Data;
3457  }
3459  return lhs.Data != rhs.Data;
3460  }
3461  };
3462 
3464  /// The kind of exception specification this is.
3466 
3467  /// Explicitly-specified list of exception types.
3469 
3470  /// Noexcept expression, if this is a computed noexcept specification.
3471  Expr *NoexceptExpr = nullptr;
3472 
3473  /// The function whose exception specification this is, for
3474  /// EST_Unevaluated and EST_Uninstantiated.
3475  FunctionDecl *SourceDecl = nullptr;
3476 
3477  /// The function template whose exception specification this is instantiated
3478  /// from, for EST_Uninstantiated.
3479  FunctionDecl *SourceTemplate = nullptr;
3480 
3481  ExceptionSpecInfo() = default;
3482 
3484  };
3485 
3486  /// Extra information about a function prototype.
3487  struct ExtProtoInfo {
3489  bool Variadic : 1;
3491  unsigned char TypeQuals = 0;
3492  RefQualifierKind RefQualifier = RQ_None;
3494  const ExtParameterInfo *ExtParameterInfos = nullptr;
3495 
3497  : Variadic(false), HasTrailingReturn(false) {}
3498 
3500  : ExtInfo(CC), Variadic(false), HasTrailingReturn(false) {}
3501 
3503  ExtProtoInfo Result(*this);
3504  Result.ExceptionSpec = O;
3505  return Result;
3506  }
3507  };
3508 
3509 private:
3510  friend class ASTContext; // ASTContext creates these.
3511 
3512  /// Determine whether there are any argument types that
3513  /// contain an unexpanded parameter pack.
3514  static bool containsAnyUnexpandedParameterPack(const QualType *ArgArray,
3515  unsigned numArgs) {
3516  for (unsigned Idx = 0; Idx < numArgs; ++Idx)
3517  if (ArgArray[Idx]->containsUnexpandedParameterPack())
3518  return true;
3519 
3520  return false;
3521  }
3522 
3524  QualType canonical, const ExtProtoInfo &epi);
3525 
3526  /// The number of parameters this function has, not counting '...'.
3527  unsigned NumParams : 15;
3528 
3529  /// The number of types in the exception spec, if any.
3530  unsigned NumExceptions : 9;
3531 
3532  /// The type of exception specification this function has.
3533  unsigned ExceptionSpecType : 4;
3534 
3535  /// Whether this function has extended parameter information.
3536  unsigned HasExtParameterInfos : 1;
3537 
3538  /// Whether the function is variadic.
3539  unsigned Variadic : 1;
3540 
3541  /// Whether this function has a trailing return type.
3542  unsigned HasTrailingReturn : 1;
3543 
3544  // ParamInfo - There is an variable size array after the class in memory that
3545  // holds the parameter types.
3546 
3547  // Exceptions - There is another variable size array after ArgInfo that
3548  // holds the exception types.
3549 
3550  // NoexceptExpr - Instead of Exceptions, there may be a single Expr* pointing
3551  // to the expression in the noexcept() specifier.
3552 
3553  // ExceptionSpecDecl, ExceptionSpecTemplate - Instead of Exceptions, there may
3554  // be a pair of FunctionDecl* pointing to the function which should be used to
3555  // instantiate this function type's exception specification, and the function
3556  // from which it should be instantiated.
3557 
3558  // ExtParameterInfos - A variable size array, following the exception
3559  // specification and of length NumParams, holding an ExtParameterInfo
3560  // for each of the parameters. This only appears if HasExtParameterInfos
3561  // is true.
3562 
3563  const ExtParameterInfo *getExtParameterInfosBuffer() const {
3564  assert(hasExtParameterInfos());
3565 
3566  // Find the end of the exception specification.
3567  const auto *ptr = reinterpret_cast<const char *>(exception_begin());
3568  ptr += getExceptionSpecSize();
3569 
3570  return reinterpret_cast<const ExtParameterInfo *>(ptr);
3571  }
3572 
3573  static size_t getExceptionSpecSize(ExceptionSpecificationType EST,
3574  unsigned NumExceptions) {
3575  switch (EST) {
3576  case EST_None:
3577  case EST_DynamicNone:
3578  case EST_MSAny:
3579  case EST_BasicNoexcept:
3580  case EST_Unparsed:
3581  return 0;
3582 
3583  case EST_Dynamic:
3584  return NumExceptions * sizeof(QualType);
3585 
3586  case EST_DependentNoexcept:
3587  case EST_NoexceptFalse:
3588  case EST_NoexceptTrue:
3589  return sizeof(Expr *);
3590 
3591  case EST_Uninstantiated:
3592  return 2 * sizeof(FunctionDecl *);
3593 
3594  case EST_Unevaluated:
3595  return sizeof(FunctionDecl *);
3596  }
3597  llvm_unreachable("bad exception specification kind");
3598  }
3599  size_t getExceptionSpecSize() const {
3600  return getExceptionSpecSize(getExceptionSpecType(), getNumExceptions());
3601  }
3602 
3603 public:
3604  unsigned getNumParams() const { return NumParams; }
3605 
3606  QualType getParamType(unsigned i) const {
3607  assert(i < NumParams && "invalid parameter index");
3608  return param_type_begin()[i];
3609  }
3610 
3612  return llvm::makeArrayRef(param_type_begin(), param_type_end());
3613  }
3614 
3616  ExtProtoInfo EPI;
3617  EPI.ExtInfo = getExtInfo();
3618  EPI.Variadic = isVariadic();
3619  EPI.HasTrailingReturn = hasTrailingReturn();
3620  EPI.ExceptionSpec.Type = getExceptionSpecType();
3621  EPI.TypeQuals = static_cast<unsigned char>(getTypeQuals());
3622  EPI.RefQualifier = getRefQualifier();
3623  if (EPI.ExceptionSpec.Type == EST_Dynamic) {
3624  EPI.ExceptionSpec.Exceptions = exceptions();
3625  } else if (isComputedNoexcept(EPI.ExceptionSpec.Type)) {
3626  EPI.ExceptionSpec.NoexceptExpr = getNoexceptExpr();
3627  } else if (EPI.ExceptionSpec.Type == EST_Uninstantiated) {
3628  EPI.ExceptionSpec.SourceDecl = getExceptionSpecDecl();
3629  EPI.ExceptionSpec.SourceTemplate = getExceptionSpecTemplate();
3630  } else if (EPI.ExceptionSpec.Type == EST_Unevaluated) {
3631  EPI.ExceptionSpec.SourceDecl = getExceptionSpecDecl();
3632  }
3633  if (hasExtParameterInfos())
3634  EPI.ExtParameterInfos = getExtParameterInfosBuffer();
3635  return EPI;
3636  }
3637 
3638  /// Get the kind of exception specification on this function.
3640  return static_cast<ExceptionSpecificationType>(ExceptionSpecType);
3641  }
3642 
3643  /// Return whether this function has any kind of exception spec.
3644  bool hasExceptionSpec() const {
3645  return getExceptionSpecType() != EST_None;
3646  }
3647 
3648  /// Return whether this function has a dynamic (throw) exception spec.
3650  return isDynamicExceptionSpec(getExceptionSpecType());
3651  }
3652 
3653  /// Return whether this function has a noexcept exception spec.
3655  return isNoexceptExceptionSpec(getExceptionSpecType());
3656  }
3657 
3658  /// Return whether this function has a dependent exception spec.
3659  bool hasDependentExceptionSpec() const;
3660 
3661  /// Return whether this function has an instantiation-dependent exception
3662  /// spec.
3663  bool hasInstantiationDependentExceptionSpec() const;
3664 
3665  unsigned getNumExceptions() const { return NumExceptions; }
3666  QualType getExceptionType(unsigned i) const {
3667  assert(i < NumExceptions && "Invalid exception number!");
3668  return exception_begin()[i];
3669  }
3671  if (!isComputedNoexcept(getExceptionSpecType()))
3672  return nullptr;
3673  // NoexceptExpr sits where the arguments end.
3674  return *reinterpret_cast<Expr *const *>(param_type_end());
3675  }
3676 
3677  /// If this function type has an exception specification which hasn't
3678  /// been determined yet (either because it has not been evaluated or because
3679  /// it has not been instantiated), this is the function whose exception
3680  /// specification is represented by this type.
3682  if (getExceptionSpecType() != EST_Uninstantiated &&
3683  getExceptionSpecType() != EST_Unevaluated)
3684  return nullptr;
3685  return reinterpret_cast<FunctionDecl *const *>(param_type_end())[0];
3686  }
3687 
3688  /// If this function type has an uninstantiated exception
3689  /// specification, this is the function whose exception specification
3690  /// should be instantiated to find the exception specification for
3691  /// this type.
3693  if (getExceptionSpecType() != EST_Uninstantiated)
3694  return nullptr;
3695  return reinterpret_cast<FunctionDecl *const *>(param_type_end())[1];
3696  }
3697 
3698  /// Determine whether this function type has a non-throwing exception
3699  /// specification.
3700  CanThrowResult canThrow() const;
3701 
3702  /// Determine whether this function type has a non-throwing exception
3703  /// specification. If this depends on template arguments, returns
3704  /// \c ResultIfDependent.
3705  bool isNothrow(bool ResultIfDependent = false) const {
3706  return ResultIfDependent ? canThrow() != CT_Can
3707  : canThrow() == CT_Cannot;
3708  }
3709 
3710  bool isVariadic() const { return Variadic; }
3711 
3712  /// Determines whether this function prototype contains a
3713  /// parameter pack at the end.
3714  ///
3715  /// A function template whose last parameter is a parameter pack can be
3716  /// called with an arbitrary number of arguments, much like a variadic
3717  /// function.
3718  bool isTemplateVariadic() const;
3719 
3720  bool hasTrailingReturn() const { return HasTrailingReturn; }
3721 
3722  unsigned getTypeQuals() const { return FunctionType::getTypeQuals(); }
3723 
3724  /// Retrieve the ref-qualifier associated with this function type.
3726  return static_cast<RefQualifierKind>(FunctionTypeBits.RefQualifier);
3727  }
3728 
3730  using param_type_range = llvm::iterator_range<param_type_iterator>;
3731 
3733  return param_type_range(param_type_begin(), param_type_end());
3734  }
3735 
3737  return reinterpret_cast<const QualType *>(this+1);
3738  }
3739 
3741  return param_type_begin() + NumParams;
3742  }
3743 
3744  using exception_iterator = const QualType *;
3745 
3747  return llvm::makeArrayRef(exception_begin(), exception_end());
3748  }
3749 
3751  // exceptions begin where arguments end
3752  return param_type_end();
3753  }
3754 
3756  if (getExceptionSpecType() != EST_Dynamic)
3757  return exception_begin();
3758  return exception_begin() + NumExceptions;
3759  }
3760 
3761  /// Is there any interesting extra information for any of the parameters
3762  /// of this function type?
3763  bool hasExtParameterInfos() const { return HasExtParameterInfos; }
3765  assert(hasExtParameterInfos());
3766  return ArrayRef<ExtParameterInfo>(getExtParameterInfosBuffer(),
3767  getNumParams());
3768  }
3769 
3770  /// Return a pointer to the beginning of the array of extra parameter
3771  /// information, if present, or else null if none of the parameters
3772  /// carry it. This is equivalent to getExtProtoInfo().ExtParameterInfos.
3774  if (!hasExtParameterInfos())
3775  return nullptr;
3776  return getExtParameterInfosBuffer();
3777  }
3778 
3780  assert(I < getNumParams() && "parameter index out of range");
3781  if (hasExtParameterInfos())
3782  return getExtParameterInfosBuffer()[I];
3783  return ExtParameterInfo();
3784  }
3785 
3786  ParameterABI getParameterABI(unsigned I) const {
3787  assert(I < getNumParams() && "parameter index out of range");
3788  if (hasExtParameterInfos())
3789  return getExtParameterInfosBuffer()[I].getABI();
3790  return ParameterABI::Ordinary;
3791  }
3792 
3793  bool isParamConsumed(unsigned I) const {
3794  assert(I < getNumParams() && "parameter index out of range");
3795  if (hasExtParameterInfos())
3796  return getExtParameterInfosBuffer()[I].isConsumed();
3797  return false;
3798  }
3799 
3800  bool isSugared() const { return false; }
3801  QualType desugar() const { return QualType(this, 0); }
3802 
3803  void printExceptionSpecification(raw_ostream &OS,
3804  const PrintingPolicy &Policy) const;
3805 
3806  static bool classof(const Type *T) {
3807  return T->getTypeClass() == FunctionProto;
3808  }
3809 
3810  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx);
3811  static void Profile(llvm::FoldingSetNodeID &ID, QualType Result,
3812  param_type_iterator ArgTys, unsigned NumArgs,
3813  const ExtProtoInfo &EPI, const ASTContext &Context,
3814  bool Canonical);
3815 };
3816 
3817 /// Represents the dependent type named by a dependently-scoped
3818 /// typename using declaration, e.g.
3819 /// using typename Base<T>::foo;
3820 ///
3821 /// Template instantiation turns these into the underlying type.
3822 class UnresolvedUsingType : public Type {
3823  friend class ASTContext; // ASTContext creates these.
3824 
3826 
3828  : Type(UnresolvedUsing, QualType(), true, true, false,
3829  /*ContainsUnexpandedParameterPack=*/false),
3830  Decl(const_cast<UnresolvedUsingTypenameDecl*>(D)) {}
3831 
3832 public:
3833  UnresolvedUsingTypenameDecl *getDecl() const { return Decl; }
3834 
3835  bool isSugared() const { return false; }
3836  QualType desugar() const { return QualType(this, 0); }
3837 
3838  static bool classof(const Type *T) {
3839  return T->getTypeClass() == UnresolvedUsing;
3840  }
3841 
3842  void Profile(llvm::FoldingSetNodeID &ID) {
3843  return Profile(ID, Decl);
3844  }
3845 
3846  static void Profile(llvm::FoldingSetNodeID &ID,
3848  ID.AddPointer(D);
3849  }
3850 };
3851 
3852 class TypedefType : public Type {
3854 
3855 protected:
3856  friend class ASTContext; // ASTContext creates these.
3857 
3859  : Type(tc, can, can->isDependentType(),
3860  can->isInstantiationDependentType(),
3861  can->isVariablyModifiedType(),
3862  /*ContainsUnexpandedParameterPack=*/false),
3863  Decl(const_cast<TypedefNameDecl*>(D)) {
3864  assert(!isa<TypedefType>(can) && "Invalid canonical type");
3865  }
3866 
3867 public:
3868  TypedefNameDecl *getDecl() const { return Decl; }
3869 
3870  bool isSugared() const { return true; }
3871  QualType desugar() const;
3872 
3873  static bool classof(const Type *T) { return T->getTypeClass() == Typedef; }
3874 };
3875 
3876 /// Represents a `typeof` (or __typeof__) expression (a GCC extension).
3877 class TypeOfExprType : public Type {
3878  Expr *TOExpr;
3879 
3880 protected:
3881  friend class ASTContext; // ASTContext creates these.
3882 
3883  TypeOfExprType(Expr *E, QualType can = QualType());
3884 
3885 public:
3886  Expr *getUnderlyingExpr() const { return TOExpr; }
3887 
3888  /// Remove a single level of sugar.
3889  QualType desugar() const;
3890 
3891  /// Returns whether this type directly provides sugar.
3892  bool isSugared() const;
3893 
3894  static bool classof(const Type *T) { return T->getTypeClass() == TypeOfExpr; }
3895 };
3896 
3897 /// Internal representation of canonical, dependent
3898 /// `typeof(expr)` types.
3899 ///
3900 /// This class is used internally by the ASTContext to manage
3901 /// canonical, dependent types, only. Clients will only see instances
3902 /// of this class via TypeOfExprType nodes.
3904  : public TypeOfExprType, public llvm::FoldingSetNode {
3905  const ASTContext &Context;
3906 
3907 public:
3909  : TypeOfExprType(E), Context(Context) {}
3910 
3911  void Profile(llvm::FoldingSetNodeID &ID) {
3912  Profile(ID, Context, getUnderlyingExpr());
3913  }
3914 
3915  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3916  Expr *E);
3917 };
3918 
3919 /// Represents `typeof(type)`, a GCC extension.
3920 class TypeOfType : public Type {
3921  friend class ASTContext; // ASTContext creates these.
3922 
3923  QualType TOType;
3924 
3926  : Type(TypeOf, can, T->isDependentType(),
3927  T->isInstantiationDependentType(),
3928  T->isVariablyModifiedType(),
3929  T->containsUnexpandedParameterPack()),
3930  TOType(T) {
3931  assert(!isa<TypedefType>(can) && "Invalid canonical type");
3932  }
3933 
3934 public:
3935  QualType getUnderlyingType() const { return TOType; }
3936 
3937  /// Remove a single level of sugar.
3938  QualType desugar() const { return getUnderlyingType(); }
3939 
3940  /// Returns whether this type directly provides sugar.
3941  bool isSugared() const { return true; }
3942 
3943  static bool classof(const Type *T) { return T->getTypeClass() == TypeOf; }
3944 };
3945 
3946 /// Represents the type `decltype(expr)` (C++11).
3947 class DecltypeType : public Type {
3948  Expr *E;
3949  QualType UnderlyingType;
3950 
3951 protected:
3952  friend class ASTContext; // ASTContext creates these.
3953 
3954  DecltypeType(Expr *E, QualType underlyingType, QualType can = QualType());
3955 
3956 public:
3957  Expr *getUnderlyingExpr() const { return E; }
3958  QualType getUnderlyingType() const { return UnderlyingType; }
3959 
3960  /// Remove a single level of sugar.
3961  QualType desugar() const;
3962 
3963  /// Returns whether this type directly provides sugar.
3964  bool isSugared() const;
3965 
3966  static bool classof(const Type *T) { return T->getTypeClass() == Decltype; }
3967 };
3968 
3969 /// Internal representation of canonical, dependent
3970 /// decltype(expr) types.
3971 ///
3972 /// This class is used internally by the ASTContext to manage
3973 /// canonical, dependent types, only. Clients will only see instances
3974 /// of this class via DecltypeType nodes.
3975 class DependentDecltypeType : public DecltypeType, public llvm::FoldingSetNode {
3976  const ASTContext &Context;
3977 
3978 public:
3979  DependentDecltypeType(const ASTContext &Context, Expr *E);
3980 
3981  void Profile(llvm::FoldingSetNodeID &ID) {
3982  Profile(ID, Context, getUnderlyingExpr());
3983  }
3984 
3985  static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
3986  Expr *E);
3987 };
3988 
3989 /// A unary type transform, which is a type constructed from another.
3990 class UnaryTransformType : public Type {
3991 public:
3992  enum UTTKind {
3993  EnumUnderlyingType
3994  };
3995 
3996 private:
3997  /// The untransformed type.
3998  QualType BaseType;
3999 
4000  /// The transformed type if not dependent, otherwise the same as BaseType.
4001  QualType UnderlyingType;
4002 
4003  UTTKind UKind;
4004 
4005 protected:
4006  friend class ASTContext;
4007 
4008  UnaryTransformType(QualType BaseTy, QualType UnderlyingTy, UTTKind UKind,
4009  QualType CanonicalTy);
4010 
4011 public:
4012  bool isSugared() const { return !isDependentType(); }
4013  QualType desugar() const { return UnderlyingType; }
4014 
4015  QualType getUnderlyingType() const { return UnderlyingType; }
4016  QualType getBaseType() const { return BaseType; }
4017 
4018  UTTKind getUTTKind() const { return UKind; }
4019 
4020  static bool classof(const Type *T) {
4021  return T->getTypeClass() == UnaryTransform;
4022  }
4023 };
4024 
4025 /// Internal representation of canonical, dependent
4026 /// __underlying_type(type) types.
4027 ///
4028 /// This class is used internally by the ASTContext to manage
4029 /// canonical, dependent types, only. Clients will only see instances
4030 /// of this class via UnaryTransformType nodes.
4032  public llvm::FoldingSetNode {
4033 public:
4035  UTTKind UKind);
4036 
4037  void Profile(llvm::FoldingSetNodeID &ID) {
4038  Profile(ID, getBaseType(), getUTTKind());
4039  }
4040 
4041  static void Profile(llvm::FoldingSetNodeID &ID, QualType BaseType,
4042  UTTKind UKind) {
4043  ID.AddPointer(BaseType.getAsOpaquePtr());
4044  ID.AddInteger((unsigned)UKind);
4045  }
4046 };
4047 
4048 class TagType : public Type {
4049  friend class ASTReader;
4050 
4051  /// Stores the TagDecl associated with this type. The decl may point to any
4052  /// TagDecl that declares the entity.
4053  TagDecl *decl;
4054 
4055 protected:
4056  TagType(TypeClass TC, const TagDecl *D, QualType can);
4057 
4058 public:
4059  TagDecl *getDecl() const;
4060 
4061  /// Determines whether this type is in the process of being defined.
4062  bool isBeingDefined() const;
4063 
4064  static bool classof(const Type *T) {
4065  return T->getTypeClass() >= TagFirst && T->getTypeClass() <= TagLast;
4066  }
4067 };
4068 
4069 /// A helper class that allows the use of isa/cast/dyncast
4070 /// to detect TagType objects of structs/unions/classes.
4071 class RecordType : public TagType {
4072 protected:
4073  friend class ASTContext; // ASTContext creates these.
4074 
4075  explicit RecordType(const RecordDecl *D)
4076  : TagType(Record, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4078  : TagType(TC, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4079 
4080 public:
4081  RecordDecl *getDecl() const {
4082  return reinterpret_cast<RecordDecl*>(TagType::getDecl());
4083  }
4084 
4085  /// Recursively check all fields in the record for const-ness. If any field
4086  /// is declared const, return true. Otherwise, return false.
4087  bool hasConstFields() const;
4088 
4089  bool isSugared() const { return false; }
4090  QualType desugar() const { return QualType(this, 0); }
4091 
4092  static bool classof(const Type *T) { return T->getTypeClass() == Record; }
4093 };
4094 
4095 /// A helper class that allows the use of isa/cast/dyncast
4096 /// to detect TagType objects of enums.
4097 class EnumType : public TagType {
4098  friend class ASTContext; // ASTContext creates these.
4099 
4100  explicit EnumType(const EnumDecl *D)
4101  : TagType(Enum, reinterpret_cast<const TagDecl*>(D), QualType()) {}
4102 
4103 public:
4104  EnumDecl *getDecl() const {
4105  return reinterpret_cast<EnumDecl*>(TagType::getDecl());
4106  }
4107 
4108  bool isSugared() const { return false; }
4109  QualType desugar() const { return QualType(this, 0); }
4110 
4111  static bool classof(const Type *T) { return T->getTypeClass() == Enum; }
4112 };
4113 
4114 /// An attributed type is a type to which a type attribute has been applied.
4115 ///
4116 /// The "modified type" is the fully-sugared type to which the attributed
4117 /// type was applied; generally it is not canonically equivalent to the
4118 /// attributed type. The "equivalent type" is the minimally-desugared type
4119 /// which the type is canonically equivalent to.
4120 ///
4121 /// For example, in the following attributed type:
4122 /// int32_t __attribute__((vector_size(16)))
4123 /// - the modified type is the TypedefType for int32_t
4124 /// - the equivalent type is VectorType(16, int32_t)
4125 /// - the canonical type is VectorType(16, int)
4126 class AttributedType : public Type, public llvm::FoldingSetNode {
4127 public:
4128  // It is really silly to have yet another attribute-kind enum, but
4129  // clang::attr::Kind doesn't currently cover the pure type attrs.
4130  enum Kind {
4131  // Expression operand.
4137 
4138  FirstExprOperandKind = attr_address_space,
4139  LastExprOperandKind = attr_neon_polyvector_type,
4140 
4141  // Enumerated operand (string or keyword).
4146 
4147  FirstEnumOperandKind = attr_objc_gc,
4148  LastEnumOperandKind = attr_pcs_vfp,
4149 
4150  // No operand.
4176  };
4177 
4178 private:
4179  friend class ASTContext; // ASTContext creates these
4180 
4181  QualType ModifiedType;
4182  QualType EquivalentType;
4183 
4184  AttributedType(QualType canon, Kind attrKind, QualType modified,
4185  QualType equivalent)
4186  : Type(Attributed, canon, equivalent->isDependentType(),
4187  equivalent->isInstantiationDependentType(),
4188  equivalent->isVariablyModifiedType(),
4189  equivalent->containsUnexpandedParameterPack()),
4190  ModifiedType(modified), EquivalentType(equivalent) {
4191  AttributedTypeBits.AttrKind = attrKind;
4192  }
4193 
4194 public:
4195  Kind getAttrKind() const {
4196  return static_cast<Kind>(AttributedTypeBits.AttrKind);
4197  }
4198 
4199  QualType getModifiedType() const { return ModifiedType; }
4200  QualType getEquivalentType() const { return EquivalentType; }
4201 
4202  bool isSugared() const { return true; }
4203  QualType desugar() const { return getEquivalentType(); }
4204 
4205  /// Does this attribute behave like a type qualifier?
4206  ///
4207  /// A type qualifier adjusts a type to provide specialized rules for
4208  /// a specific object, like the standard const and volatile qualifiers.
4209  /// This includes attributes controlling things like nullability,
4210  /// address spaces, and ARC ownership. The value of the object is still
4211  /// largely described by the modified type.
4212  ///
4213  /// In contrast, many type attributes "rewrite" their modified type to
4214  /// produce a fundamentally different type, not necessarily related in any
4215  /// formalizable way to the original type. For example, calling convention
4216  /// and vector attributes are not simple type qualifiers.
4217  ///
4218  /// Type qualifiers are often, but not always, reflected in the canonical
4219  /// type.
4220  bool isQualifier() const;
4221 
4222  bool isMSTypeSpec() const;
4223 
4224  bool isCallingConv() const;
4225 
4226  llvm::Optional<NullabilityKind> getImmediateNullability() const;
4227 
4228  /// Retrieve the attribute kind corresponding to the given
4229  /// nullability kind.
4231  switch (kind) {
4233  return attr_nonnull;
4234 
4236  return attr_nullable;
4237 
4239  return attr_null_unspecified;
4240  }
4241  llvm_unreachable("Unknown nullability kind.");
4242  }
4243 
4244  /// Strip off the top-level nullability annotation on the given
4245  /// type, if it's there.
4246  ///
4247  /// \param T The type to strip. If the type is exactly an
4248  /// AttributedType specifying nullability (without looking through
4249  /// type sugar), the nullability is returned and this type changed
4250  /// to the underlying modified type.
4251  ///
4252  /// \returns the top-level nullability, if present.
4253  static Optional<NullabilityKind> stripOuterNullability(QualType &T);
4254 
4255  void Profile(llvm::FoldingSetNodeID &ID) {
4256  Profile(ID, getAttrKind(), ModifiedType, EquivalentType);
4257  }
4258 
4259  static void Profile(llvm::FoldingSetNodeID &ID, Kind attrKind,
4260  QualType modified, QualType equivalent) {
4261  ID.AddInteger(attrKind);
4262  ID.AddPointer(modified.getAsOpaquePtr());
4263  ID.AddPointer(equivalent.getAsOpaquePtr());
4264  }
4265 
4266  static bool classof(const Type *T) {
4267  return T->getTypeClass() == Attributed;
4268  }
4269 };
4270 
4271 class TemplateTypeParmType : public Type, public llvm::FoldingSetNode {
4272  friend class ASTContext; // ASTContext creates these
4273 
4274  // Helper data collector for canonical types.
4275  struct CanonicalTTPTInfo {
4276  unsigned Depth : 15;
4277  unsigned ParameterPack : 1;
4278  unsigned Index : 16;
4279  };
4280 
4281  union {
4282  // Info for the canonical type.
4283  CanonicalTTPTInfo CanTTPTInfo;
4284 
4285  // Info for the non-canonical type.
4287  };
4288 
4289  /// Build a non-canonical type.
4291  : Type(TemplateTypeParm, Canon, /*Dependent=*/true,
4292  /*InstantiationDependent=*/true,
4293  /*VariablyModified=*/false,
4294  Canon->containsUnexpandedParameterPack()),
4295  TTPDecl(TTPDecl) {}
4296 
4297  /// Build the canonical type.
4298  TemplateTypeParmType(unsigned D, unsigned I, bool PP)
4299  : Type(TemplateTypeParm, QualType(this, 0),
4300  /*Dependent=*/true,
4301  /*InstantiationDependent=*/true,
4302  /*VariablyModified=*/false, PP) {
4303  CanTTPTInfo.Depth = D;
4304  CanTTPTInfo.Index = I;
4305  CanTTPTInfo.ParameterPack = PP;
4306  }
4307 
4308  const CanonicalTTPTInfo& getCanTTPTInfo() const {
4309  QualType Can = getCanonicalTypeInternal();
4310  return Can->castAs<TemplateTypeParmType>()->CanTTPTInfo;
4311  }
4312 
4313 public:
4314  unsigned getDepth() const { return getCanTTPTInfo().Depth; }
4315  unsigned getIndex() const { return getCanTTPTInfo().Index; }
4316  bool isParameterPack() const { return getCanTTPTInfo().ParameterPack; }
4317 
4319  return isCanonicalUnqualified() ? nullptr : TTPDecl;
4320  }
4321 
4322  IdentifierInfo *getIdentifier() const;
4323 
4324  bool isSugared() const { return false; }
4325  QualType desugar() const { return QualType(this, 0); }
4326 
4327  void Profile(llvm::FoldingSetNodeID &ID) {
4328  Profile(ID, getDepth(), getIndex(), isParameterPack(), getDecl());
4329  }
4330 
4331  static void Profile(llvm::FoldingSetNodeID &ID, unsigned Depth,
4332  unsigned Index, bool ParameterPack,
4333  TemplateTypeParmDecl *TTPDecl) {
4334  ID.AddInteger(Depth);
4335  ID.AddInteger(Index);
4336  ID.AddBoolean(ParameterPack);
4337  ID.AddPointer(TTPDecl);
4338  }
4339 
4340  static bool classof(const Type *T) {
4341  return T->getTypeClass() == TemplateTypeParm;
4342  }
4343 };
4344 
4345 /// Represents the result of substituting a type for a template
4346 /// type parameter.
4347 ///
4348 /// Within an instantiated template, all template type parameters have
4349 /// been replaced with these. They are used solely to record that a
4350 /// type was originally written as a template type parameter;
4351 /// therefore they are never canonical.
4352 class SubstTemplateTypeParmType : public Type, public llvm::FoldingSetNode {
4353  friend class ASTContext;
4354 
4355  // The original type parameter.
4356  const TemplateTypeParmType *Replaced;
4357 
4359  : Type(SubstTemplateTypeParm, Canon, Canon->isDependentType(),
4360  Canon->isInstantiationDependentType(),
4361  Canon->isVariablyModifiedType(),
4362  Canon->containsUnexpandedParameterPack()),
4363  Replaced(Param) {}
4364 
4365 public:
4366  /// Gets the template parameter that was substituted for.
4368  return Replaced;
4369  }
4370 
4371  /// Gets the type that was substituted for the template
4372  /// parameter.
4374  return getCanonicalTypeInternal();
4375  }
4376 
4377  bool isSugared() const { return true; }
4378  QualType desugar() const { return getReplacementType(); }
4379 
4380  void Profile(llvm::FoldingSetNodeID &ID) {
4381  Profile(ID, getReplacedParameter(), getReplacementType());
4382  }
4383 
4384  static void Profile(llvm::FoldingSetNodeID &ID,
4385  const TemplateTypeParmType *Replaced,
4387  ID.AddPointer(Replaced);
4388  ID.AddPointer(Replacement.getAsOpaquePtr());
4389  }
4390 
4391  static bool classof(const Type *T) {
4392  return T->getTypeClass() == SubstTemplateTypeParm;
4393  }
4394 };
4395 
4396 /// Represents the result of substituting a set of types for a template
4397 /// type parameter pack.
4398 ///
4399 /// When a pack expansion in the source code contains multiple parameter packs
4400 /// and those parameter packs correspond to different levels of template
4401 /// parameter lists, this type node is used to represent a template type
4402 /// parameter pack from an outer level, which has already had its argument pack
4403 /// substituted but that still lives within a pack expansion that itself
4404 /// could not be instantiated. When actually performing a substitution into
4405 /// that pack expansion (e.g., when all template parameters have corresponding
4406 /// arguments), this type will be replaced with the \c SubstTemplateTypeParmType
4407 /// at the current pack substitution index.
4408 class SubstTemplateTypeParmPackType : public Type, public llvm::FoldingSetNode {
4409  friend class ASTContext;
4410 
4411  /// The original type parameter.
4412  const TemplateTypeParmType *Replaced;
4413 
4414  /// A pointer to the set of template arguments that this
4415  /// parameter pack is instantiated with.
4416  const TemplateArgument *Arguments;
4417 
4418  /// The number of template arguments in \c Arguments.
4419  unsigned NumArguments;
4420 
4422  QualType Canon,
4423  const TemplateArgument &ArgPack);
4424 
4425 public:
4426  IdentifierInfo *getIdentifier() const { return Replaced->getIdentifier(); }
4427 
4428  /// Gets the template parameter that was substituted for.
4430  return Replaced;
4431  }
4432 
4433  bool isSugared() const { return false; }
4434  QualType desugar() const { return QualType(this, 0); }
4435 
4436  TemplateArgument getArgumentPack() const;
4437 
4438  void Profile(llvm::FoldingSetNodeID &ID);
4439  static void Profile(llvm::FoldingSetNodeID &ID,
4440  const TemplateTypeParmType *Replaced,
4441  const TemplateArgument &ArgPack);
4442 
4443  static bool classof(const Type *T) {
4444  return T->getTypeClass() == SubstTemplateTypeParmPack;
4445  }
4446 };
4447 
4448 /// Common base class for placeholders for types that get replaced by
4449 /// placeholder type deduction: C++11 auto, C++14 decltype(auto), C++17 deduced
4450 /// class template types, and (eventually) constrained type names from the C++
4451 /// Concepts TS.
4452 ///
4453 /// These types are usually a placeholder for a deduced type. However, before
4454 /// the initializer is attached, or (usually) if the initializer is
4455 /// type-dependent, there is no deduced type and the type is canonical. In
4456 /// the latter case, it is also a dependent type.
4457 class DeducedType : public Type {
4458 protected:
4459  DeducedType(TypeClass TC, QualType DeducedAsType, bool IsDependent,
4460  bool IsInstantiationDependent, bool ContainsParameterPack)
4461  : Type(TC,
4462  // FIXME: Retain the sugared deduced type?
4463  DeducedAsType.isNull() ? QualType(this, 0)
4464  : DeducedAsType.getCanonicalType(),
4465  IsDependent, IsInstantiationDependent,
4466  /*VariablyModified=*/false, ContainsParameterPack) {
4467  if (!DeducedAsType.isNull()) {
4468  if (DeducedAsType->isDependentType())
4469  setDependent();
4470  if (DeducedAsType->isInstantiationDependentType())
4471  setInstantiationDependent();
4472  if (DeducedAsType->containsUnexpandedParameterPack())
4473  setContainsUnexpandedParameterPack();
4474  }
4475  }
4476 
4477 public:
4478  bool isSugared() const { return !isCanonicalUnqualified(); }
4479  QualType desugar() const { return getCanonicalTypeInternal(); }
4480 
4481  /// Get the type deduced for this placeholder type, or null if it's
4482  /// either not been deduced or was deduced to a dependent type.
4484  return !isCanonicalUnqualified() ? getCanonicalTypeInternal() : QualType();
4485  }
4486  bool isDeduced() const {
4487  return !isCanonicalUnqualified() || isDependentType();
4488  }
4489 
4490  static bool classof(const Type *T) {
4491  return T->getTypeClass() == Auto ||
4492  T->getTypeClass() == DeducedTemplateSpecialization;
4493  }
4494 };
4495 
4496 /// Represents a C++11 auto or C++14 decltype(auto) type.
4497 class AutoType : public DeducedType, public llvm::FoldingSetNode {
4498  friend class ASTContext; // ASTContext creates these
4499 
4500  AutoType(QualType DeducedAsType, AutoTypeKeyword Keyword,
4501  bool IsDeducedAsDependent)
4502  : DeducedType(Auto, DeducedAsType, IsDeducedAsDependent,
4503  IsDeducedAsDependent, /*ContainsPack=*/false) {
4504  AutoTypeBits.Keyword = (unsigned)Keyword;
4505  }
4506 
4507 public:
4508  bool isDecltypeAuto() const {
4509  return getKeyword() == AutoTypeKeyword::DecltypeAuto;
4510  }
4511 
4513  return (AutoTypeKeyword)AutoTypeBits.Keyword;
4514  }
4515 
4516  void Profile(llvm::FoldingSetNodeID &ID) {
4517  Profile(ID, getDeducedType(), getKeyword(), isDependentType());
4518  }
4519 
4520  static void Profile(llvm::FoldingSetNodeID &ID, QualType Deduced,
4521  AutoTypeKeyword Keyword, bool IsDependent) {
4522  ID.AddPointer(Deduced.getAsOpaquePtr());
4523  ID.AddInteger((unsigned)Keyword);
4524  ID.AddBoolean(IsDependent);
4525  }
4526 
4527  static bool classof(const Type *T) {
4528  return T->getTypeClass() == Auto;
4529  }
4530 };
4531 
4532 /// Represents a C++17 deduced template specialization type.
4534  public llvm::FoldingSetNode {
4535  friend class ASTContext; // ASTContext creates these
4536 
4537  /// The name of the template whose arguments will be deduced.
4538  TemplateName Template;
4539 
4541  QualType DeducedAsType,
4542  bool IsDeducedAsDependent)
4543  : DeducedType(DeducedTemplateSpecialization, DeducedAsType,
4544  IsDeducedAsDependent || Template.isDependent(),
4545  IsDeducedAsDependent || Template.isInstantiationDependent(),
4546  Template.containsUnexpandedParameterPack()),
4547  Template(Template) {}
4548 
4549 public:
4550  /// Retrieve the name of the template that we are deducing.
4551  TemplateName getTemplateName() const { return Template;}
4552 
4553  void Profile(llvm::FoldingSetNodeID &ID) {
4554  Profile(ID, getTemplateName(), getDeducedType(), isDependentType());
4555  }
4556 
4557  static void Profile(llvm::FoldingSetNodeID &ID, TemplateName Template,
4558  QualType Deduced, bool IsDependent) {
4559  Template.Profile(ID);
4560  ID.AddPointer(Deduced.getAsOpaquePtr());
4561  ID.AddBoolean(IsDependent);
4562  }
4563 
4564  static bool classof(const Type *T) {
4565  return T->getTypeClass() == DeducedTemplateSpecialization;
4566  }
4567 };
4568 
4569 /// Represents a type template specialization; the template
4570 /// must be a class template, a type alias template, or a template
4571 /// template parameter. A template which cannot be resolved to one of
4572 /// these, e.g. because it is written with a dependent scope
4573 /// specifier, is instead represented as a
4574 /// @c DependentTemplateSpecializationType.
4575 ///
4576 /// A non-dependent template specialization type is always "sugar",
4577 /// typically for a \c RecordType. For example, a class template
4578 /// specialization type of \c vector<int> will refer to a tag type for
4579 /// the instantiation \c std::vector<int, std::allocator<int>>
4580 ///
4581 /// Template specializations are dependent if either the template or
4582 /// any of the template arguments are dependent, in which case the
4583 /// type may also be canonical.
4584 ///
4585 /// Instances of this type are allocated with a trailing array of
4586 /// TemplateArguments, followed by a QualType representing the
4587 /// non-canonical aliased type when the template is a type alias
4588 /// template.
4589 class LLVM_ALIGNAS(/*alignof(uint64_t)*/ 8) TemplateSpecializationType
4590  : public Type,
4591  public llvm::FoldingSetNode {
4592  friend class ASTContext; // ASTContext creates these
4593 
4594  /// The name of the template being specialized. This is
4595  /// either a TemplateName::Template (in which case it is a
4596  /// ClassTemplateDecl*, a TemplateTemplateParmDecl*, or a
4597  /// TypeAliasTemplateDecl*), a
4598  /// TemplateName::SubstTemplateTemplateParmPack, or a
4599  /// TemplateName::SubstTemplateTemplateParm (in which case the
4600  /// replacement must, recursively, be one of these).
4601  TemplateName Template;
4602 
4603  /// The number of template arguments named in this class template
4604  /// specialization.
4605  unsigned NumArgs : 31;
4606 
4607  /// Whether this template specialization type is a substituted type alias.
4608  unsigned TypeAlias : 1;
4609 
4612  QualType Canon,
4613  QualType Aliased);
4614 
4615 public:
4616  /// Determine whether any of the given template arguments are dependent.
4617  static bool anyDependentTemplateArguments(ArrayRef<TemplateArgumentLoc> Args,
4618  bool &InstantiationDependent);
4619 
4620  static bool anyDependentTemplateArguments(const TemplateArgumentListInfo &,
4621  bool &InstantiationDependent);
4622 
4623  /// True if this template specialization type matches a current
4624  /// instantiation in the context in which it is found.
4625  bool isCurrentInstantiation() const {
4626  return isa<InjectedClassNameType>(getCanonicalTypeInternal());
4627  }
4628 
4629  /// Determine if this template specialization type is for a type alias
4630  /// template that has been substituted.
4631  ///
4632  /// Nearly every template specialization type whose template is an alias
4633  /// template will be substituted. However, this is not the case when
4634  /// the specialization contains a pack expansion but the template alias
4635  /// does not have a corresponding parameter pack, e.g.,
4636  ///
4637  /// \code
4638  /// template<typename T, typename U, typename V> struct S;
4639  /// template<typename T, typename U> using A = S<T, int, U>;
4640  /// template<typename... Ts> struct X {
4641  /// typedef A<Ts...> type; // not a type alias
4642  /// };
4643  /// \endcode
4644  bool isTypeAlias() const { return TypeAlias; }
4645 
4646  /// Get the aliased type, if this is a specialization of a type alias
4647  /// template.
4649  assert(isTypeAlias() && "not a type alias template specialization");
4650  return *reinterpret_cast<const QualType*>(end());
4651  }
4652 
4653  using iterator = const TemplateArgument *;
4654 
4655  iterator begin() const { return getArgs(); }
4656  iterator end() const; // defined inline in TemplateBase.h
4657 
4658  /// Retrieve the name of the template that we are specializing.
4659  TemplateName getTemplateName() const { return Template; }
4660 
4661  /// Retrieve the template arguments.
4662  const TemplateArgument *getArgs() const {
4663  return reinterpret_cast<const TemplateArgument *>(this + 1);
4664  }
4665 
4666  /// Retrieve the number of template arguments.
4667  unsigned getNumArgs() const { return NumArgs; }
4668 
4669  /// Retrieve a specific template argument as a type.
4670  /// \pre \c isArgType(Arg)
4671  const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h
4672 
4674  return {getArgs(), NumArgs};
4675  }
4676 
4677  bool isSugared() const {
4678  return !isDependentType() || isCurrentInstantiation() || isTypeAlias();
4679  }
4680 
4681  QualType desugar() const { return getCanonicalTypeInternal(); }
4682 
4683  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx) {
4684  Profile(ID, Template, template_arguments(), Ctx);
4685  if (isTypeAlias())
4686  getAliasedType().Profile(ID);
4687  }
4688 
4689  static void Profile(llvm::FoldingSetNodeID &ID, TemplateName T,
4691  const ASTContext &Context);
4692 
4693  static bool classof(const Type *T) {
4694  return T->getTypeClass() == TemplateSpecialization;
4695  }
4696 };
4697 
4698 /// Print a template argument list, including the '<' and '>'
4699 /// enclosing the template arguments.
4700 void printTemplateArgumentList(raw_ostream &OS,
4702  const PrintingPolicy &Policy);
4703 
4704 void printTemplateArgumentList(raw_ostream &OS,
4706  const PrintingPolicy &Policy);
4707 
4708 void printTemplateArgumentList(raw_ostream &OS,
4709  const TemplateArgumentListInfo &Args,
4710  const PrintingPolicy &Policy);
4711 
4712 /// The injected class name of a C++ class template or class
4713 /// template partial specialization. Used to record that a type was
4714 /// spelled with a bare identifier rather than as a template-id; the
4715 /// equivalent for non-templated classes is just RecordType.
4716 ///
4717 /// Injected class name types are always dependent. Template
4718 /// instantiation turns these into RecordTypes.
4719 ///
4720 /// Injected class name types are always canonical. This works
4721 /// because it is impossible to compare an injected class name type
4722 /// with the corresponding non-injected template type, for the same
4723 /// reason that it is impossible to directly compare template
4724 /// parameters from different dependent contexts: injected class name
4725 /// types can only occur within the scope of a particular templated
4726 /// declaration, and within that scope every template specialization
4727 /// will canonicalize to the injected class name (when appropriate
4728 /// according to the rules of the language).
4729 class InjectedClassNameType : public Type {
4730  friend class ASTContext; // ASTContext creates these.
4731  friend class ASTNodeImporter;
4732  friend class ASTReader; // FIXME: ASTContext::getInjectedClassNameType is not
4733  // currently suitable for AST reading, too much
4734  // interdependencies.
4735 
4737 
4738  /// The template specialization which this type represents.
4739  /// For example, in
4740  /// template <class T> class A { ... };
4741  /// this is A<T>, whereas in
4742  /// template <class X, class Y> class A<B<X,Y> > { ... };
4743  /// this is A<B<X,Y> >.
4744  ///
4745  /// It is always unqualified, always a template specialization type,
4746  /// and always dependent.
4747  QualType InjectedType;
4748 
4750  : Type(InjectedClassName, QualType(), /*Dependent=*/true,
4751  /*InstantiationDependent=*/true,
4752  /*VariablyModified=*/false,
4753  /*ContainsUnexpandedParameterPack=*/false),
4754  Decl(D), InjectedType(TST) {
4755  assert(isa<TemplateSpecializationType>(TST));
4756  assert(!TST.hasQualifiers());
4757  assert(TST->isDependentType());
4758  }
4759 
4760 public:
4761  QualType getInjectedSpecializationType() const { return InjectedType; }
4762 
4764  return cast<TemplateSpecializationType>(InjectedType.getTypePtr());
4765  }
4766 
4768  return getInjectedTST()->getTemplateName();
4769  }
4770 
4771  CXXRecordDecl *getDecl() const;
4772 
4773  bool isSugared() const { return false; }
4774  QualType desugar() const { return QualType(this, 0); }
4775 
4776  static bool classof(const Type *T) {
4777  return T->getTypeClass() == InjectedClassName;
4778  }
4779 };
4780 
4781 /// The kind of a tag type.
4783  /// The "struct" keyword.
4785 
4786  /// The "__interface" keyword.
4788 
4789  /// The "union" keyword.
4791 
4792  /// The "class" keyword.
4794 
4795  /// The "enum" keyword.
4797 };
4798 
4799 /// The elaboration keyword that precedes a qualified type name or
4800 /// introduces an elaborated-type-specifier.
4802  /// The "struct" keyword introduces the elaborated-type-specifier.
4804 
4805  /// The "__interface" keyword introduces the elaborated-type-specifier.
4807 
4808  /// The "union" keyword introduces the elaborated-type-specifier.
4810 
4811  /// The "class" keyword introduces the elaborated-type-specifier.
4813 
4814  /// The "enum" keyword introduces the elaborated-type-specifier.
4816 
4817  /// The "typename" keyword precedes the qualified type name, e.g.,
4818  /// \c typename T::type.
4820 
4821  /// No keyword precedes the qualified type name.
4823 };
4824 
4825 /// A helper class for Type nodes having an ElaboratedTypeKeyword.
4826 /// The keyword in stored in the free bits of the base class.
4827 /// Also provides a few static helpers for converting and printing
4828 /// elaborated type keyword and tag type kind enumerations.
4829 class TypeWithKeyword : public Type {
4830 protected:
4832  QualType Canonical, bool Dependent,
4833  bool InstantiationDependent, bool VariablyModified,
4834  bool ContainsUnexpandedParameterPack)
4835  : Type(tc, Canonical, Dependent, InstantiationDependent, VariablyModified,
4836  ContainsUnexpandedParameterPack) {
4837  TypeWithKeywordBits.Keyword = Keyword;
4838  }
4839 
4840 public:
4842  return static_cast<ElaboratedTypeKeyword>(TypeWithKeywordBits.Keyword);
4843  }
4844 
4845  /// Converts a type specifier (DeclSpec::TST) into an elaborated type keyword.
4846  static ElaboratedTypeKeyword getKeywordForTypeSpec(unsigned TypeSpec);
4847 
4848  /// Converts a type specifier (DeclSpec::TST) into a tag type kind.
4849  /// It is an error to provide a type specifier which *isn't* a tag kind here.
4850  static TagTypeKind getTagTypeKindForTypeSpec(unsigned TypeSpec);
4851 
4852  /// Converts a TagTypeKind into an elaborated type keyword.
4853  static ElaboratedTypeKeyword getKeywordForTagTypeKind(TagTypeKind Tag);
4854 
4855  /// Converts an elaborated type keyword into a TagTypeKind.
4856  /// It is an error to provide an elaborated type keyword
4857  /// which *isn't* a tag kind here.
4858  static TagTypeKind getTagTypeKindForKeyword(ElaboratedTypeKeyword Keyword);
4859 
4860  static bool KeywordIsTagTypeKind(ElaboratedTypeKeyword Keyword);
4861 
4862  static StringRef getKeywordName(ElaboratedTypeKeyword Keyword);
4863 
4865  return getKeywordName(getKeywordForTagTypeKind(Kind));
4866  }
4867 
4869  static CannotCastToThisType classof(const Type *);
4870 };
4871 
4872 /// Represents a type that was referred to using an elaborated type
4873 /// keyword, e.g., struct S, or via a qualified name, e.g., N::M::type,
4874 /// or both.
4875 ///
4876 /// This type is used to keep track of a type name as written in the
4877 /// source code, including tag keywords and any nested-name-specifiers.
4878 /// The type itself is always "sugar", used to express what was written
4879 /// in the source code but containing no additional semantic information.
4880 class ElaboratedType : public TypeWithKeyword, public llvm::FoldingSetNode {
4881  friend class ASTContext; // ASTContext creates these
4882 
4883  /// The nested name specifier containing the qualifier.
4884  NestedNameSpecifier *NNS;
4885 
4886  /// The type that this qualified name refers to.
4887  QualType NamedType;
4888 
4889  /// The (re)declaration of this tag type owned by this occurrence, or nullptr
4890  /// if none.
4891  TagDecl *OwnedTagDecl;
4892 
4894  QualType NamedType, QualType CanonType, TagDecl *OwnedTagDecl)
4895  : TypeWithKeyword(Keyword, Elaborated, CanonType,
4896  NamedType->isDependentType(),
4897  NamedType->isInstantiationDependentType(),
4898  NamedType->isVariablyModifiedType(),
4899  NamedType->containsUnexpandedParameterPack()),
4900  NNS(NNS), NamedType(NamedType), OwnedTagDecl(OwnedTagDecl) {
4901  assert(!(Keyword == ETK_None && NNS == nullptr) &&
4902  "ElaboratedType cannot have elaborated type keyword "
4903  "and name qualifier both null.");
4904  }
4905 
4906 public:
4907  ~ElaboratedType();
4908 
4909  /// Retrieve the qualification on this type.
4910  NestedNameSpecifier *getQualifier() const { return NNS; }
4911 
4912  /// Retrieve the type named by the qualified-id.
4913  QualType getNamedType() const { return NamedType; }
4914 
4915  /// Remove a single level of sugar.
4916  QualType desugar() const { return getNamedType(); }
4917 
4918  /// Returns whether this type directly provides sugar.
4919  bool isSugared() const { return true; }
4920 
4921  /// Return the (re)declaration of this type owned by this occurrence of this
4922  /// type, or nullptr if none.
4923  TagDecl *getOwnedTagDecl() const { return OwnedTagDecl; }
4924 
4925  void Profile(llvm::FoldingSetNodeID &ID) {
4926  Profile(ID, getKeyword(), NNS, NamedType, OwnedTagDecl);
4927  }
4928 
4929  static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
4930  NestedNameSpecifier *NNS, QualType NamedType,
4931  TagDecl *OwnedTagDecl) {
4932  ID.AddInteger(Keyword);
4933  ID.AddPointer(NNS);
4934  NamedType.Profile(ID);
4935  ID.AddPointer(OwnedTagDecl);
4936  }
4937 
4938  static bool classof(const Type *T) {
4939  return T->getTypeClass() == Elaborated;
4940  }
4941 };
4942 
4943 /// Represents a qualified type name for which the type name is
4944 /// dependent.
4945 ///
4946 /// DependentNameType represents a class of dependent types that involve a
4947 /// possibly dependent nested-name-specifier (e.g., "T::") followed by a
4948 /// name of a type. The DependentNameType may start with a "typename" (for a
4949 /// typename-specifier), "class", "struct", "union", or "enum" (for a
4950 /// dependent elaborated-type-specifier), or nothing (in contexts where we
4951 /// know that we must be referring to a type, e.g., in a base class specifier).
4952 /// Typically the nested-name-specifier is dependent, but in MSVC compatibility
4953 /// mode, this type is used with non-dependent names to delay name lookup until
4954 /// instantiation.
4955 class DependentNameType : public TypeWithKeyword, public llvm::FoldingSetNode {
4956  friend class ASTContext; // ASTContext creates these
4957 
4958  /// The nested name specifier containing the qualifier.
4959  NestedNameSpecifier *NNS;
4960 
4961  /// The type that this typename specifier refers to.
4962  const IdentifierInfo *Name;
4963 
4965  const IdentifierInfo *Name, QualType CanonType)
4966  : TypeWithKeyword(Keyword, DependentName, CanonType, /*Dependent=*/true,
4967  /*InstantiationDependent=*/true,
4968  /*VariablyModified=*/false,
4969  NNS->containsUnexpandedParameterPack()),
4970  NNS(NNS), Name(Name) {}
4971 
4972 public:
4973  /// Retrieve the qualification on this type.
4974  NestedNameSpecifier *getQualifier() const { return NNS; }
4975 
4976  /// Retrieve the type named by the typename specifier as an identifier.
4977  ///
4978  /// This routine will return a non-NULL identifier pointer when the
4979  /// form of the original typename was terminated by an identifier,
4980  /// e.g., "typename T::type".
4982  return Name;
4983  }
4984 
4985  bool isSugared() const { return false; }
4986  QualType desugar() const { return QualType(this, 0); }
4987 
4988  void Profile(llvm::FoldingSetNodeID &ID) {
4989  Profile(ID, getKeyword(), NNS, Name);
4990  }
4991 
4992  static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
4993  NestedNameSpecifier *NNS, const IdentifierInfo *Name) {
4994  ID.AddInteger(Keyword);
4995  ID.AddPointer(NNS);
4996  ID.AddPointer(Name);
4997  }
4998 
4999  static bool classof(const Type *T) {
5000  return T->getTypeClass() == DependentName;
5001  }
5002 };
5003 
5004 /// Represents a template specialization type whose template cannot be
5005 /// resolved, e.g.
5006 /// A<T>::template B<T>
5007 class LLVM_ALIGNAS(/*alignof(uint64_t)*/ 8) DependentTemplateSpecializationType
5008  : public TypeWithKeyword,
5009  public llvm::FoldingSetNode {
5010  friend class ASTContext; // ASTContext creates these
5011 
5012  /// The nested name specifier containing the qualifier.
5013  NestedNameSpecifier *NNS;
5014 
5015  /// The identifier of the template.
5016  const IdentifierInfo *Name;
5017 
5018  /// The number of template arguments named in this class template
5019  /// specialization.
5020  unsigned NumArgs;
5021 
5023  NestedNameSpecifier *NNS,
5024  const IdentifierInfo *Name,
5026  QualType Canon);
5027 
5028  const TemplateArgument *getArgBuffer() const {
5029  return reinterpret_cast<const TemplateArgument*>(this+1);
5030  }
5031 
5032  TemplateArgument *getArgBuffer() {
5033  return reinterpret_cast<TemplateArgument*>(this+1);
5034  }
5035 
5036 public:
5037  NestedNameSpecifier *getQualifier() const { return NNS; }
5038  const IdentifierInfo *getIdentifier() const { return Name; }
5039 
5040  /// Retrieve the template arguments.
5041  const TemplateArgument *getArgs() const {
5042  return getArgBuffer();
5043  }
5044 
5045  /// Retrieve the number of template arguments.
5046  unsigned getNumArgs() const { return NumArgs; }
5047 
5048  const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h
5049 
5051  return {getArgs(), NumArgs};
5052  }
5053 
5054  using iterator = const TemplateArgument *;
5055 
5056  iterator begin() const { return getArgs(); }
5057  iterator end() const; // inline in TemplateBase.h
5058 
5059  bool isSugared() const { return false; }
5060  QualType desugar() const { return QualType(this, 0); }
5061 
5062  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
5063  Profile(ID, Context, getKeyword(), NNS, Name, {getArgs(), NumArgs});
5064  }
5065 
5066  static void Profile(llvm::FoldingSetNodeID &ID,
5067  const ASTContext &Context,
5068  ElaboratedTypeKeyword Keyword,
5069  NestedNameSpecifier *Qualifier,
5070  const IdentifierInfo *Name,
5072 
5073  static bool classof(const Type *T) {
5074  return T->getTypeClass() == DependentTemplateSpecialization;
5075  }
5076 };
5077 
5078 /// Represents a pack expansion of types.
5079 ///
5080 /// Pack expansions are part of C++11 variadic templates. A pack
5081 /// expansion contains a pattern, which itself contains one or more
5082 /// "unexpanded" parameter packs. When instantiated, a pack expansion
5083 /// produces a series of types, each instantiated from the pattern of
5084 /// the expansion, where the Ith instantiation of the pattern uses the
5085 /// Ith arguments bound to each of the unexpanded parameter packs. The
5086 /// pack expansion is considered to "expand" these unexpanded
5087 /// parameter packs.
5088 ///
5089 /// \code
5090 /// template<typename ...Types> struct tuple;
5091 ///
5092 /// template<typename ...Types>
5093 /// struct tuple_of_references {
5094 /// typedef tuple<Types&...> type;
5095 /// };
5096 /// \endcode
5097 ///
5098 /// Here, the pack expansion \c Types&... is represented via a
5099 /// PackExpansionType whose pattern is Types&.
5100 class PackExpansionType : public Type, public llvm::FoldingSetNode {
5101  friend class ASTContext; // ASTContext creates these
5102 
5103  /// The pattern of the pack expansion.
5104  QualType Pattern;
5105 
5106  /// The number of expansions that this pack expansion will
5107  /// generate when substituted (+1), or indicates that
5108  ///
5109  /// This field will only have a non-zero value when some of the parameter
5110  /// packs that occur within the pattern have been substituted but others have
5111  /// not.
5112  unsigned NumExpansions;
5113 
5114  PackExpansionType(QualType Pattern, QualType Canon,
5115  Optional<unsigned> NumExpansions)
5116  : Type(PackExpansion, Canon, /*Dependent=*/Pattern->isDependentType(),
5117  /*InstantiationDependent=*/true,
5118  /*VariablyModified=*/Pattern->isVariablyModifiedType(),
5119  /*ContainsUnexpandedParameterPack=*/false),
5120  Pattern(Pattern),
5121  NumExpansions(NumExpansions ? *NumExpansions + 1 : 0) {}
5122 
5123 public:
5124  /// Retrieve the pattern of this pack expansion, which is the
5125  /// type that will be repeatedly instantiated when instantiating the
5126  /// pack expansion itself.
5127  QualType getPattern() const { return Pattern; }
5128 
5129  /// Retrieve the number of expansions that this pack expansion will
5130  /// generate, if known.
5132  if (NumExpansions)
5133  return NumExpansions - 1;
5134 
5135  return None;
5136  }
5137 
5138  bool isSugared() const { return !Pattern->isDependentType(); }
5139  QualType desugar() const { return isSugared() ? Pattern : QualType(this, 0); }
5140 
5141  void Profile(llvm::FoldingSetNodeID &ID) {
5142  Profile(ID, getPattern(), getNumExpansions());
5143  }
5144 
5145  static void Profile(llvm::FoldingSetNodeID &ID, QualType Pattern,
5146  Optional<unsigned> NumExpansions) {
5147  ID.AddPointer(Pattern.getAsOpaquePtr());
5148  ID.AddBoolean(NumExpansions.hasValue());
5149  if (NumExpansions)
5150  ID.AddInteger(*NumExpansions);
5151  }
5152 
5153  static bool classof(const Type *T) {
5154  return T->getTypeClass() == PackExpansion;
5155  }
5156 };
5157 
5158 /// This class wraps the list of protocol qualifiers. For types that can
5159 /// take ObjC protocol qualifers, they can subclass this class.
5160 template <class T>
5162 protected:
5163  ObjCProtocolQualifiers() = default;
5164 
5166  return const_cast<ObjCProtocolQualifiers*>(this)->getProtocolStorage();
5167  }
5168 
5170  return static_cast<T*>(this)->getProtocolStorageImpl();
5171  }
5172 
5173  void setNumProtocols(unsigned N) {
5174  static_cast<T*>(this)->setNumProtocolsImpl(N);
5175  }
5176