1 //===- CanonicalType.h - C Language Family Type Representation --*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file defines the CanQual class template, which provides access to
10 //  canonical types.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_AST_CANONICALTYPE_H
15 #define LLVM_CLANG_AST_CANONICALTYPE_H
16 
17 #include "clang/AST/Type.h"
18 #include "clang/Basic/Diagnostic.h"
19 #include "clang/Basic/SourceLocation.h"
20 #include "llvm/ADT/ArrayRef.h"
21 #include "llvm/ADT/FoldingSet.h"
22 #include "llvm/ADT/iterator.h"
23 #include "llvm/Support/Casting.h"
24 #include "llvm/Support/PointerLikeTypeTraits.h"
25 #include <cassert>
26 #include <iterator>
27 #include <type_traits>
28 
29 namespace clang {
30 
31 template<typename T> class CanProxy;
32 template<typename T> struct CanProxyAdaptor;
33 class CXXRecordDecl;
34 class EnumDecl;
35 class Expr;
36 class IdentifierInfo;
37 class ObjCInterfaceDecl;
38 class RecordDecl;
39 class TagDecl;
40 class TemplateTypeParmDecl;
41 
42 //----------------------------------------------------------------------------//
43 // Canonical, qualified type template
44 //----------------------------------------------------------------------------//
45 
46 /// Represents a canonical, potentially-qualified type.
47 ///
48 /// The CanQual template is a lightweight smart pointer that provides access
49 /// to the canonical representation of a type, where all typedefs and other
50 /// syntactic sugar has been eliminated. A CanQualType may also have various
51 /// qualifiers (const, volatile, restrict) attached to it.
52 ///
53 /// The template type parameter @p T is one of the Type classes (PointerType,
54 /// BuiltinType, etc.). The type stored within @c CanQual<T> will be of that
55 /// type (or some subclass of that type). The typedef @c CanQualType is just
56 /// a shorthand for @c CanQual<Type>.
57 ///
58 /// An instance of @c CanQual<T> can be implicitly converted to a
59 /// @c CanQual<U> when T is derived from U, which essentially provides an
60 /// implicit upcast. For example, @c CanQual<LValueReferenceType> can be
61 /// converted to @c CanQual<ReferenceType>. Note that any @c CanQual type can
62 /// be implicitly converted to a QualType, but the reverse operation requires
63 /// a call to ASTContext::getCanonicalType().
64 template<typename T = Type>
65 class CanQual {
66   /// The actual, canonical type.
67   QualType Stored;
68 
69 public:
70   /// Constructs a NULL canonical type.
71   CanQual() = default;
72 
73   /// Converting constructor that permits implicit upcasting of
74   /// canonical type pointers.
75   template <typename U>
76   CanQual(const CanQual<U> &Other,
77           std::enable_if_t<std::is_base_of<T, U>::value, int> = 0);
78 
79   /// Retrieve the underlying type pointer, which refers to a
80   /// canonical type.
81   ///
82   /// The underlying pointer must not be nullptr.
83   const T *getTypePtr() const { return cast<T>(Stored.getTypePtr()); }
84 
85   /// Retrieve the underlying type pointer, which refers to a
86   /// canonical type, or nullptr.
87   const T *getTypePtrOrNull() const {
88     return cast_or_null<T>(Stored.getTypePtrOrNull());
89   }
90 
91   /// Implicit conversion to a qualified type.
92   operator QualType() const { return Stored; }
93 
94   /// Implicit conversion to bool.
95   explicit operator bool() const { return !isNull(); }
96 
97   bool isNull() const {
98     return Stored.isNull();
99   }
100 
101   SplitQualType split() const { return Stored.split(); }
102 
103   /// Retrieve a canonical type pointer with a different static type,
104   /// upcasting or downcasting as needed.
105   ///
106   /// The getAs() function is typically used to try to downcast to a
107   /// more specific (canonical) type in the type system. For example:
108   ///
109   /// @code
110   /// void f(CanQual<Type> T) {
111   ///   if (CanQual<PointerType> Ptr = T->getAs<PointerType>()) {
112   ///     // look at Ptr's pointee type
113   ///   }
114   /// }
115   /// @endcode
116   ///
117   /// \returns A proxy pointer to the same type, but with the specified
118   /// static type (@p U). If the dynamic type is not the specified static type
119   /// or a derived class thereof, a NULL canonical type.
120   template<typename U> CanProxy<U> getAs() const;
121 
122   template<typename U> CanProxy<U> castAs() const;
123 
124   /// Overloaded arrow operator that produces a canonical type
125   /// proxy.
126   CanProxy<T> operator->() const;
127 
128   /// Retrieve all qualifiers.
129   Qualifiers getQualifiers() const { return Stored.getLocalQualifiers(); }
130 
131   /// Retrieve the const/volatile/restrict qualifiers.
132   unsigned getCVRQualifiers() const { return Stored.getLocalCVRQualifiers(); }
133 
134   /// Determines whether this type has any qualifiers
135   bool hasQualifiers() const { return Stored.hasLocalQualifiers(); }
136 
137   bool isConstQualified() const {
138     return Stored.isLocalConstQualified();
139   }
140 
141   bool isVolatileQualified() const {
142     return Stored.isLocalVolatileQualified();
143   }
144 
145   bool isRestrictQualified() const {
146     return Stored.isLocalRestrictQualified();
147   }
148 
149   /// Determines if this canonical type is furthermore
150   /// canonical as a parameter.  The parameter-canonicalization
151   /// process decays arrays to pointers and drops top-level qualifiers.
152   bool isCanonicalAsParam() const {
153     return Stored.isCanonicalAsParam();
154   }
155 
156   /// Retrieve the unqualified form of this type.
157   CanQual<T> getUnqualifiedType() const;
158 
159   /// Retrieves a version of this type with const applied.
160   /// Note that this does not always yield a canonical type.
161   QualType withConst() const {
162     return Stored.withConst();
163   }
164 
165   /// Determines whether this canonical type is more qualified than
166   /// the @p Other canonical type.
167   bool isMoreQualifiedThan(CanQual<T> Other) const {
168     return Stored.isMoreQualifiedThan(Other.Stored);
169   }
170 
171   /// Determines whether this canonical type is at least as qualified as
172   /// the @p Other canonical type.
173   bool isAtLeastAsQualifiedAs(CanQual<T> Other) const {
174     return Stored.isAtLeastAsQualifiedAs(Other.Stored);
175   }
176 
177   /// If the canonical type is a reference type, returns the type that
178   /// it refers to; otherwise, returns the type itself.
179   CanQual<Type> getNonReferenceType() const;
180 
181   /// Retrieve the internal representation of this canonical type.
182   void *getAsOpaquePtr() const { return Stored.getAsOpaquePtr(); }
183 
184   /// Construct a canonical type from its internal representation.
185   static CanQual<T> getFromOpaquePtr(void *Ptr);
186 
187   /// Builds a canonical type from a QualType.
188   ///
189   /// This routine is inherently unsafe, because it requires the user to
190   /// ensure that the given type is a canonical type with the correct
191   // (dynamic) type.
192   static CanQual<T> CreateUnsafe(QualType Other);
193 
194   void dump() const { Stored.dump(); }
195 
196   void Profile(llvm::FoldingSetNodeID &ID) const {
197     ID.AddPointer(getAsOpaquePtr());
198   }
199 };
200 
201 template<typename T, typename U>
202 inline bool operator==(CanQual<T> x, CanQual<U> y) {
203   return x.getAsOpaquePtr() == y.getAsOpaquePtr();
204 }
205 
206 template<typename T, typename U>
207 inline bool operator!=(CanQual<T> x, CanQual<U> y) {
208   return x.getAsOpaquePtr() != y.getAsOpaquePtr();
209 }
210 
211 /// Represents a canonical, potentially-qualified type.
212 using CanQualType = CanQual<Type>;
213 
214 inline CanQualType Type::getCanonicalTypeUnqualified() const {
215   return CanQualType::CreateUnsafe(getCanonicalTypeInternal());
216 }
217 
218 inline const DiagnosticBuilder &operator<<(const DiagnosticBuilder &DB,
219                                            CanQualType T) {
220   DB << static_cast<QualType>(T);
221   return DB;
222 }
223 
224 //----------------------------------------------------------------------------//
225 // Internal proxy classes used by canonical types
226 //----------------------------------------------------------------------------//
227 
228 #define LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(Accessor)                    \
229 CanQualType Accessor() const {                                           \
230 return CanQualType::CreateUnsafe(this->getTypePtr()->Accessor());      \
231 }
232 
233 #define LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(Type, Accessor)             \
234 Type Accessor() const { return this->getTypePtr()->Accessor(); }
235 
236 /// Base class of all canonical proxy types, which is responsible for
237 /// storing the underlying canonical type and providing basic conversions.
238 template<typename T>
239 class CanProxyBase {
240 protected:
241   CanQual<T> Stored;
242 
243 public:
244   /// Retrieve the pointer to the underlying Type
245   const T *getTypePtr() const { return Stored.getTypePtr(); }
246 
247   /// Implicit conversion to the underlying pointer.
248   ///
249   /// Also provides the ability to use canonical type proxies in a Boolean
250   // context,e.g.,
251   /// @code
252   ///   if (CanQual<PointerType> Ptr = T->getAs<PointerType>()) { ... }
253   /// @endcode
254   operator const T*() const { return this->Stored.getTypePtrOrNull(); }
255 
256   /// Try to convert the given canonical type to a specific structural
257   /// type.
258   template<typename U> CanProxy<U> getAs() const {
259     return this->Stored.template getAs<U>();
260   }
261 
262   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(Type::TypeClass, getTypeClass)
263 
264   // Type predicates
265   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjectType)
266   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isIncompleteType)
267   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isSizelessType)
268   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isSizelessBuiltinType)
269   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isIncompleteOrObjectType)
270   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isVariablyModifiedType)
271   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isIntegerType)
272   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isEnumeralType)
273   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isBooleanType)
274   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isCharType)
275   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isWideCharType)
276   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isIntegralType)
277   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isIntegralOrEnumerationType)
278   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isRealFloatingType)
279   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isComplexType)
280   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isAnyComplexType)
281   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isFloatingType)
282   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isRealType)
283   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isArithmeticType)
284   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isVoidType)
285   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isDerivedType)
286   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isScalarType)
287   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isAggregateType)
288   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isAnyPointerType)
289   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isVoidPointerType)
290   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isFunctionPointerType)
291   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isMemberFunctionPointerType)
292   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isClassType)
293   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isStructureType)
294   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isInterfaceType)
295   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isStructureOrClassType)
296   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isUnionType)
297   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isComplexIntegerType)
298   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isNullPtrType)
299   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isDependentType)
300   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isOverloadableType)
301   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isArrayType)
302   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasPointerRepresentation)
303   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasObjCPointerRepresentation)
304   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasIntegerRepresentation)
305   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasSignedIntegerRepresentation)
306   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasUnsignedIntegerRepresentation)
307   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasFloatingRepresentation)
308   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isPromotableIntegerType)
309   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isSignedIntegerType)
310   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isUnsignedIntegerType)
311   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isSignedIntegerOrEnumerationType)
312   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isUnsignedIntegerOrEnumerationType)
313   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isConstantSizeType)
314   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isSpecifierType)
315   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(CXXRecordDecl*, getAsCXXRecordDecl)
316 
317   /// Retrieve the proxy-adaptor type.
318   ///
319   /// This arrow operator is used when CanProxyAdaptor has been specialized
320   /// for the given type T. In that case, we reference members of the
321   /// CanProxyAdaptor specialization. Otherwise, this operator will be hidden
322   /// by the arrow operator in the primary CanProxyAdaptor template.
323   const CanProxyAdaptor<T> *operator->() const {
324     return static_cast<const CanProxyAdaptor<T> *>(this);
325   }
326 };
327 
328 /// Replaceable canonical proxy adaptor class that provides the link
329 /// between a canonical type and the accessors of the type.
330 ///
331 /// The CanProxyAdaptor is a replaceable class template that is instantiated
332 /// as part of each canonical proxy type. The primary template merely provides
333 /// redirection to the underlying type (T), e.g., @c PointerType. One can
334 /// provide specializations of this class template for each underlying type
335 /// that provide accessors returning canonical types (@c CanQualType) rather
336 /// than the more typical @c QualType, to propagate the notion of "canonical"
337 /// through the system.
338 template<typename T>
339 struct CanProxyAdaptor : CanProxyBase<T> {};
340 
341 /// Canonical proxy type returned when retrieving the members of a
342 /// canonical type or as the result of the @c CanQual<T>::getAs member
343 /// function.
344 ///
345 /// The CanProxy type mainly exists as a proxy through which operator-> will
346 /// look to either map down to a raw T* (e.g., PointerType*) or to a proxy
347 /// type that provides canonical-type access to the fields of the type.
348 template<typename T>
349 class CanProxy : public CanProxyAdaptor<T> {
350 public:
351   /// Build a NULL proxy.
352   CanProxy() = default;
353 
354   /// Build a proxy to the given canonical type.
355   CanProxy(CanQual<T> Stored) { this->Stored = Stored; }
356 
357   /// Implicit conversion to the stored canonical type.
358   operator CanQual<T>() const { return this->Stored; }
359 };
360 
361 } // namespace clang
362 
363 namespace llvm {
364 
365 /// Implement simplify_type for CanQual<T>, so that we can dyn_cast from
366 /// CanQual<T> to a specific Type class. We're prefer isa/dyn_cast/cast/etc.
367 /// to return smart pointer (proxies?).
368 template<typename T>
369 struct simplify_type< ::clang::CanQual<T>> {
370   using SimpleType = const T *;
371 
372   static SimpleType getSimplifiedValue(::clang::CanQual<T> Val) {
373     return Val.getTypePtr();
374   }
375 };
376 
377 // Teach SmallPtrSet that CanQual<T> is "basically a pointer".
378 template<typename T>
379 struct PointerLikeTypeTraits<clang::CanQual<T>> {
380   static void *getAsVoidPointer(clang::CanQual<T> P) {
381     return P.getAsOpaquePtr();
382   }
383 
384   static clang::CanQual<T> getFromVoidPointer(void *P) {
385     return clang::CanQual<T>::getFromOpaquePtr(P);
386   }
387 
388   // qualifier information is encoded in the low bits.
389   static constexpr int NumLowBitsAvailable = 0;
390 };
391 
392 } // namespace llvm
393 
394 namespace clang {
395 
396 //----------------------------------------------------------------------------//
397 // Canonical proxy adaptors for canonical type nodes.
398 //----------------------------------------------------------------------------//
399 
400 /// Iterator adaptor that turns an iterator over canonical QualTypes
401 /// into an iterator over CanQualTypes.
402 template <typename InputIterator>
403 struct CanTypeIterator
404     : llvm::iterator_adaptor_base<
405           CanTypeIterator<InputIterator>, InputIterator,
406           typename std::iterator_traits<InputIterator>::iterator_category,
407           CanQualType,
408           typename std::iterator_traits<InputIterator>::difference_type,
409           CanProxy<Type>, CanQualType> {
410   CanTypeIterator() = default;
411   explicit CanTypeIterator(InputIterator Iter)
412       : CanTypeIterator::iterator_adaptor_base(std::move(Iter)) {}
413 
414   CanQualType operator*() const { return CanQualType::CreateUnsafe(*this->I); }
415   CanProxy<Type> operator->() const;
416 };
417 
418 template<>
419 struct CanProxyAdaptor<ComplexType> : public CanProxyBase<ComplexType> {
420   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getElementType)
421 };
422 
423 template<>
424 struct CanProxyAdaptor<PointerType> : public CanProxyBase<PointerType> {
425   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
426 };
427 
428 template<>
429 struct CanProxyAdaptor<BlockPointerType>
430   : public CanProxyBase<BlockPointerType> {
431   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
432 };
433 
434 template<>
435 struct CanProxyAdaptor<ReferenceType> : public CanProxyBase<ReferenceType> {
436   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
437 };
438 
439 template<>
440 struct CanProxyAdaptor<LValueReferenceType>
441   : public CanProxyBase<LValueReferenceType> {
442   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
443 };
444 
445 template<>
446 struct CanProxyAdaptor<RValueReferenceType>
447   : public CanProxyBase<RValueReferenceType> {
448   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
449 };
450 
451 template<>
452 struct CanProxyAdaptor<MemberPointerType>
453   : public CanProxyBase<MemberPointerType> {
454   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
455   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(const Type *, getClass)
456 };
457 
458 // CanProxyAdaptors for arrays are intentionally unimplemented because
459 // they are not safe.
460 template<> struct CanProxyAdaptor<ArrayType>;
461 template<> struct CanProxyAdaptor<ConstantArrayType>;
462 template<> struct CanProxyAdaptor<IncompleteArrayType>;
463 template<> struct CanProxyAdaptor<VariableArrayType>;
464 template<> struct CanProxyAdaptor<DependentSizedArrayType>;
465 
466 template<>
467 struct CanProxyAdaptor<DependentSizedExtVectorType>
468   : public CanProxyBase<DependentSizedExtVectorType> {
469   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getElementType)
470   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(const Expr *, getSizeExpr)
471   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(SourceLocation, getAttributeLoc)
472 };
473 
474 template<>
475 struct CanProxyAdaptor<VectorType> : public CanProxyBase<VectorType> {
476   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getElementType)
477   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getNumElements)
478 };
479 
480 template<>
481 struct CanProxyAdaptor<ExtVectorType> : public CanProxyBase<ExtVectorType> {
482   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getElementType)
483   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getNumElements)
484 };
485 
486 template<>
487 struct CanProxyAdaptor<FunctionType> : public CanProxyBase<FunctionType> {
488   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getReturnType)
489   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(FunctionType::ExtInfo, getExtInfo)
490 };
491 
492 template<>
493 struct CanProxyAdaptor<FunctionNoProtoType>
494   : public CanProxyBase<FunctionNoProtoType> {
495   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getReturnType)
496   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(FunctionType::ExtInfo, getExtInfo)
497 };
498 
499 template<>
500 struct CanProxyAdaptor<FunctionProtoType>
501   : public CanProxyBase<FunctionProtoType> {
502   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getReturnType)
503   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(FunctionType::ExtInfo, getExtInfo)
504   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getNumParams)
505   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasExtParameterInfos)
506   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(
507             ArrayRef<FunctionProtoType::ExtParameterInfo>, getExtParameterInfos)
508 
509   CanQualType getParamType(unsigned i) const {
510     return CanQualType::CreateUnsafe(this->getTypePtr()->getParamType(i));
511   }
512 
513   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isVariadic)
514   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(Qualifiers, getMethodQuals)
515 
516   using param_type_iterator =
517       CanTypeIterator<FunctionProtoType::param_type_iterator>;
518 
519   param_type_iterator param_type_begin() const {
520     return param_type_iterator(this->getTypePtr()->param_type_begin());
521   }
522 
523   param_type_iterator param_type_end() const {
524     return param_type_iterator(this->getTypePtr()->param_type_end());
525   }
526 
527   // Note: canonical function types never have exception specifications
528 };
529 
530 template<>
531 struct CanProxyAdaptor<TypeOfType> : public CanProxyBase<TypeOfType> {
532   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getUnderlyingType)
533 };
534 
535 template<>
536 struct CanProxyAdaptor<DecltypeType> : public CanProxyBase<DecltypeType> {
537   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(Expr *, getUnderlyingExpr)
538   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getUnderlyingType)
539 };
540 
541 template <>
542 struct CanProxyAdaptor<UnaryTransformType>
543     : public CanProxyBase<UnaryTransformType> {
544   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getBaseType)
545   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getUnderlyingType)
546   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(UnaryTransformType::UTTKind, getUTTKind)
547 };
548 
549 template<>
550 struct CanProxyAdaptor<TagType> : public CanProxyBase<TagType> {
551   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(TagDecl *, getDecl)
552   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isBeingDefined)
553 };
554 
555 template<>
556 struct CanProxyAdaptor<RecordType> : public CanProxyBase<RecordType> {
557   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(RecordDecl *, getDecl)
558   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isBeingDefined)
559   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, hasConstFields)
560 };
561 
562 template<>
563 struct CanProxyAdaptor<EnumType> : public CanProxyBase<EnumType> {
564   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(EnumDecl *, getDecl)
565   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isBeingDefined)
566 };
567 
568 template<>
569 struct CanProxyAdaptor<TemplateTypeParmType>
570   : public CanProxyBase<TemplateTypeParmType> {
571   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getDepth)
572   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getIndex)
573   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isParameterPack)
574   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(TemplateTypeParmDecl *, getDecl)
575   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(IdentifierInfo *, getIdentifier)
576 };
577 
578 template<>
579 struct CanProxyAdaptor<ObjCObjectType>
580   : public CanProxyBase<ObjCObjectType> {
581   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getBaseType)
582   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(const ObjCInterfaceDecl *,
583                                       getInterface)
584   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCUnqualifiedId)
585   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCUnqualifiedClass)
586   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCQualifiedId)
587   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCQualifiedClass)
588 
589   using qual_iterator = ObjCObjectPointerType::qual_iterator;
590 
591   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(qual_iterator, qual_begin)
592   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(qual_iterator, qual_end)
593   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, qual_empty)
594   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getNumProtocols)
595 };
596 
597 template<>
598 struct CanProxyAdaptor<ObjCObjectPointerType>
599   : public CanProxyBase<ObjCObjectPointerType> {
600   LLVM_CLANG_CANPROXY_TYPE_ACCESSOR(getPointeeType)
601   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(const ObjCInterfaceType *,
602                                       getInterfaceType)
603   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCIdType)
604   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCClassType)
605   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCQualifiedIdType)
606   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, isObjCQualifiedClassType)
607 
608   using qual_iterator = ObjCObjectPointerType::qual_iterator;
609 
610   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(qual_iterator, qual_begin)
611   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(qual_iterator, qual_end)
612   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(bool, qual_empty)
613   LLVM_CLANG_CANPROXY_SIMPLE_ACCESSOR(unsigned, getNumProtocols)
614 };
615 
616 //----------------------------------------------------------------------------//
617 // Method and function definitions
618 //----------------------------------------------------------------------------//
619 template<typename T>
620 inline CanQual<T> CanQual<T>::getUnqualifiedType() const {
621   return CanQual<T>::CreateUnsafe(Stored.getLocalUnqualifiedType());
622 }
623 
624 template<typename T>
625 inline CanQual<Type> CanQual<T>::getNonReferenceType() const {
626   if (CanQual<ReferenceType> RefType = getAs<ReferenceType>())
627     return RefType->getPointeeType();
628   else
629     return *this;
630 }
631 
632 template<typename T>
633 CanQual<T> CanQual<T>::getFromOpaquePtr(void *Ptr) {
634   CanQual<T> Result;
635   Result.Stored = QualType::getFromOpaquePtr(Ptr);
636   assert((!Result || Result.Stored.getAsOpaquePtr() == (void*)-1 ||
637           Result.Stored.isCanonical()) && "Type is not canonical!");
638   return Result;
639 }
640 
641 template<typename T>
642 CanQual<T> CanQual<T>::CreateUnsafe(QualType Other) {
643   assert((Other.isNull() || Other.isCanonical()) && "Type is not canonical!");
644   assert((Other.isNull() || isa<T>(Other.getTypePtr())) &&
645          "Dynamic type does not meet the static type's requires");
646   CanQual<T> Result;
647   Result.Stored = Other;
648   return Result;
649 }
650 
651 template<typename T>
652 template<typename U>
653 CanProxy<U> CanQual<T>::getAs() const {
654   static_assert(!TypeIsArrayType<T>::value,
655                 "ArrayType cannot be used with getAs!");
656 
657   if (Stored.isNull())
658     return CanProxy<U>();
659 
660   if (isa<U>(Stored.getTypePtr()))
661     return CanQual<U>::CreateUnsafe(Stored);
662 
663   return CanProxy<U>();
664 }
665 
666 template<typename T>
667 template<typename U>
668 CanProxy<U> CanQual<T>::castAs() const {
669   static_assert(!TypeIsArrayType<U>::value,
670                 "ArrayType cannot be used with castAs!");
671 
672   assert(!Stored.isNull() && isa<U>(Stored.getTypePtr()));
673   return CanQual<U>::CreateUnsafe(Stored);
674 }
675 
676 template<typename T>
677 CanProxy<T> CanQual<T>::operator->() const {
678   return CanProxy<T>(*this);
679 }
680 
681 template <typename InputIterator>
682 CanProxy<Type> CanTypeIterator<InputIterator>::operator->() const {
683   return CanProxy<Type>(*this);
684 }
685 
686 } // namespace clang
687 
688 #endif // LLVM_CLANG_AST_CANONICALTYPE_H
689