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  1. //===- ASTContext.h - Context to hold long-lived AST nodes ------*- C++ -*-===//
  2. //
  3. // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  4. // See https://llvm.org/LICENSE.txt for license information.
  5. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  6. //
  7. //===----------------------------------------------------------------------===//
  8. //
  9. /// \file
  10. /// Defines the clang::ASTContext interface.
  11. //
  12. //===----------------------------------------------------------------------===//
  13.  
  14. #ifndef LLVM_CLANG_AST_ASTCONTEXT_H
  15. #define LLVM_CLANG_AST_ASTCONTEXT_H
  16.  
  17. #include "clang/AST/ASTFwd.h"
  18. #include "clang/AST/CanonicalType.h"
  19. #include "clang/AST/CommentCommandTraits.h"
  20. #include "clang/AST/ComparisonCategories.h"
  21. #include "clang/AST/Decl.h"
  22. #include "clang/AST/DeclarationName.h"
  23. #include "clang/AST/ExternalASTSource.h"
  24. #include "clang/AST/NestedNameSpecifier.h"
  25. #include "clang/AST/PrettyPrinter.h"
  26. #include "clang/AST/RawCommentList.h"
  27. #include "clang/AST/TemplateName.h"
  28. #include "clang/Basic/IdentifierTable.h"
  29. #include "clang/Basic/LLVM.h"
  30. #include "clang/Basic/LangOptions.h"
  31. #include "clang/Basic/NoSanitizeList.h"
  32. #include "clang/Basic/PartialDiagnostic.h"
  33. #include "clang/Basic/ProfileList.h"
  34. #include "clang/Basic/SourceLocation.h"
  35. #include "clang/Basic/XRayLists.h"
  36. #include "llvm/ADT/DenseMap.h"
  37. #include "llvm/ADT/DenseSet.h"
  38. #include "llvm/ADT/FoldingSet.h"
  39. #include "llvm/ADT/IntrusiveRefCntPtr.h"
  40. #include "llvm/ADT/MapVector.h"
  41. #include "llvm/ADT/PointerIntPair.h"
  42. #include "llvm/ADT/PointerUnion.h"
  43. #include "llvm/ADT/SmallVector.h"
  44. #include "llvm/ADT/StringMap.h"
  45. #include "llvm/ADT/StringRef.h"
  46. #include "llvm/ADT/TinyPtrVector.h"
  47. #include "llvm/Support/TypeSize.h"
  48. #include <optional>
  49.  
  50. namespace llvm {
  51.  
  52. class APFixedPoint;
  53. class FixedPointSemantics;
  54. struct fltSemantics;
  55. template <typename T, unsigned N> class SmallPtrSet;
  56.  
  57. } // namespace llvm
  58.  
  59. namespace clang {
  60.  
  61. class APValue;
  62. class ASTMutationListener;
  63. class ASTRecordLayout;
  64. class AtomicExpr;
  65. class BlockExpr;
  66. class BuiltinTemplateDecl;
  67. class CharUnits;
  68. class ConceptDecl;
  69. class CXXABI;
  70. class CXXConstructorDecl;
  71. class CXXMethodDecl;
  72. class CXXRecordDecl;
  73. class DiagnosticsEngine;
  74. class ParentMapContext;
  75. class DynTypedNodeList;
  76. class Expr;
  77. enum class FloatModeKind;
  78. class GlobalDecl;
  79. class MangleContext;
  80. class MangleNumberingContext;
  81. class MemberSpecializationInfo;
  82. class Module;
  83. struct MSGuidDeclParts;
  84. class ObjCCategoryDecl;
  85. class ObjCCategoryImplDecl;
  86. class ObjCContainerDecl;
  87. class ObjCImplDecl;
  88. class ObjCImplementationDecl;
  89. class ObjCInterfaceDecl;
  90. class ObjCIvarDecl;
  91. class ObjCMethodDecl;
  92. class ObjCPropertyDecl;
  93. class ObjCPropertyImplDecl;
  94. class ObjCProtocolDecl;
  95. class ObjCTypeParamDecl;
  96. class OMPTraitInfo;
  97. struct ParsedTargetAttr;
  98. class Preprocessor;
  99. class StoredDeclsMap;
  100. class TargetAttr;
  101. class TargetInfo;
  102. class TemplateDecl;
  103. class TemplateParameterList;
  104. class TemplateTemplateParmDecl;
  105. class TemplateTypeParmDecl;
  106. class TypeConstraint;
  107. class UnresolvedSetIterator;
  108. class UsingShadowDecl;
  109. class VarTemplateDecl;
  110. class VTableContextBase;
  111. struct BlockVarCopyInit;
  112.  
  113. namespace Builtin {
  114.  
  115. class Context;
  116.  
  117. } // namespace Builtin
  118.  
  119. enum BuiltinTemplateKind : int;
  120. enum OpenCLTypeKind : uint8_t;
  121.  
  122. namespace comments {
  123.  
  124. class FullComment;
  125.  
  126. } // namespace comments
  127.  
  128. namespace interp {
  129.  
  130. class Context;
  131.  
  132. } // namespace interp
  133.  
  134. namespace serialization {
  135. template <class> class AbstractTypeReader;
  136. } // namespace serialization
  137.  
  138. enum class AlignRequirementKind {
  139.   /// The alignment was not explicit in code.
  140.   None,
  141.  
  142.   /// The alignment comes from an alignment attribute on a typedef.
  143.   RequiredByTypedef,
  144.  
  145.   /// The alignment comes from an alignment attribute on a record type.
  146.   RequiredByRecord,
  147.  
  148.   /// The alignment comes from an alignment attribute on a enum type.
  149.   RequiredByEnum,
  150. };
  151.  
  152. struct TypeInfo {
  153.   uint64_t Width = 0;
  154.   unsigned Align = 0;
  155.   AlignRequirementKind AlignRequirement;
  156.  
  157.   TypeInfo() : AlignRequirement(AlignRequirementKind::None) {}
  158.   TypeInfo(uint64_t Width, unsigned Align,
  159.            AlignRequirementKind AlignRequirement)
  160.       : Width(Width), Align(Align), AlignRequirement(AlignRequirement) {}
  161.   bool isAlignRequired() {
  162.     return AlignRequirement != AlignRequirementKind::None;
  163.   }
  164. };
  165.  
  166. struct TypeInfoChars {
  167.   CharUnits Width;
  168.   CharUnits Align;
  169.   AlignRequirementKind AlignRequirement;
  170.  
  171.   TypeInfoChars() : AlignRequirement(AlignRequirementKind::None) {}
  172.   TypeInfoChars(CharUnits Width, CharUnits Align,
  173.                 AlignRequirementKind AlignRequirement)
  174.       : Width(Width), Align(Align), AlignRequirement(AlignRequirement) {}
  175.   bool isAlignRequired() {
  176.     return AlignRequirement != AlignRequirementKind::None;
  177.   }
  178. };
  179.  
  180. /// Holds long-lived AST nodes (such as types and decls) that can be
  181. /// referred to throughout the semantic analysis of a file.
  182. class ASTContext : public RefCountedBase<ASTContext> {
  183.   friend class NestedNameSpecifier;
  184.  
  185.   mutable SmallVector<Type *, 0> Types;
  186.   mutable llvm::FoldingSet<ExtQuals> ExtQualNodes;
  187.   mutable llvm::FoldingSet<ComplexType> ComplexTypes;
  188.   mutable llvm::FoldingSet<PointerType> PointerTypes{GeneralTypesLog2InitSize};
  189.   mutable llvm::FoldingSet<AdjustedType> AdjustedTypes;
  190.   mutable llvm::FoldingSet<BlockPointerType> BlockPointerTypes;
  191.   mutable llvm::FoldingSet<LValueReferenceType> LValueReferenceTypes;
  192.   mutable llvm::FoldingSet<RValueReferenceType> RValueReferenceTypes;
  193.   mutable llvm::FoldingSet<MemberPointerType> MemberPointerTypes;
  194.   mutable llvm::ContextualFoldingSet<ConstantArrayType, ASTContext &>
  195.       ConstantArrayTypes;
  196.   mutable llvm::FoldingSet<IncompleteArrayType> IncompleteArrayTypes;
  197.   mutable std::vector<VariableArrayType*> VariableArrayTypes;
  198.   mutable llvm::FoldingSet<DependentSizedArrayType> DependentSizedArrayTypes;
  199.   mutable llvm::FoldingSet<DependentSizedExtVectorType>
  200.     DependentSizedExtVectorTypes;
  201.   mutable llvm::FoldingSet<DependentAddressSpaceType>
  202.       DependentAddressSpaceTypes;
  203.   mutable llvm::FoldingSet<VectorType> VectorTypes;
  204.   mutable llvm::FoldingSet<DependentVectorType> DependentVectorTypes;
  205.   mutable llvm::FoldingSet<ConstantMatrixType> MatrixTypes;
  206.   mutable llvm::FoldingSet<DependentSizedMatrixType> DependentSizedMatrixTypes;
  207.   mutable llvm::FoldingSet<FunctionNoProtoType> FunctionNoProtoTypes;
  208.   mutable llvm::ContextualFoldingSet<FunctionProtoType, ASTContext&>
  209.     FunctionProtoTypes;
  210.   mutable llvm::FoldingSet<DependentTypeOfExprType> DependentTypeOfExprTypes;
  211.   mutable llvm::FoldingSet<DependentDecltypeType> DependentDecltypeTypes;
  212.   mutable llvm::FoldingSet<TemplateTypeParmType> TemplateTypeParmTypes;
  213.   mutable llvm::FoldingSet<ObjCTypeParamType> ObjCTypeParamTypes;
  214.   mutable llvm::FoldingSet<SubstTemplateTypeParmType>
  215.     SubstTemplateTypeParmTypes;
  216.   mutable llvm::FoldingSet<SubstTemplateTypeParmPackType>
  217.     SubstTemplateTypeParmPackTypes;
  218.   mutable llvm::ContextualFoldingSet<TemplateSpecializationType, ASTContext&>
  219.     TemplateSpecializationTypes;
  220.   mutable llvm::FoldingSet<ParenType> ParenTypes{GeneralTypesLog2InitSize};
  221.   mutable llvm::FoldingSet<UsingType> UsingTypes;
  222.   mutable llvm::FoldingSet<TypedefType> TypedefTypes;
  223.   mutable llvm::FoldingSet<ElaboratedType> ElaboratedTypes{
  224.       GeneralTypesLog2InitSize};
  225.   mutable llvm::FoldingSet<DependentNameType> DependentNameTypes;
  226.   mutable llvm::ContextualFoldingSet<DependentTemplateSpecializationType,
  227.                                      ASTContext&>
  228.     DependentTemplateSpecializationTypes;
  229.   llvm::FoldingSet<PackExpansionType> PackExpansionTypes;
  230.   mutable llvm::FoldingSet<ObjCObjectTypeImpl> ObjCObjectTypes;
  231.   mutable llvm::FoldingSet<ObjCObjectPointerType> ObjCObjectPointerTypes;
  232.   mutable llvm::FoldingSet<DependentUnaryTransformType>
  233.     DependentUnaryTransformTypes;
  234.   mutable llvm::ContextualFoldingSet<AutoType, ASTContext&> AutoTypes;
  235.   mutable llvm::FoldingSet<DeducedTemplateSpecializationType>
  236.     DeducedTemplateSpecializationTypes;
  237.   mutable llvm::FoldingSet<AtomicType> AtomicTypes;
  238.   mutable llvm::FoldingSet<AttributedType> AttributedTypes;
  239.   mutable llvm::FoldingSet<PipeType> PipeTypes;
  240.   mutable llvm::FoldingSet<BitIntType> BitIntTypes;
  241.   mutable llvm::FoldingSet<DependentBitIntType> DependentBitIntTypes;
  242.   llvm::FoldingSet<BTFTagAttributedType> BTFTagAttributedTypes;
  243.  
  244.   mutable llvm::FoldingSet<QualifiedTemplateName> QualifiedTemplateNames;
  245.   mutable llvm::FoldingSet<DependentTemplateName> DependentTemplateNames;
  246.   mutable llvm::FoldingSet<SubstTemplateTemplateParmStorage>
  247.     SubstTemplateTemplateParms;
  248.   mutable llvm::ContextualFoldingSet<SubstTemplateTemplateParmPackStorage,
  249.                                      ASTContext&>
  250.     SubstTemplateTemplateParmPacks;
  251.  
  252.   /// The set of nested name specifiers.
  253.   ///
  254.   /// This set is managed by the NestedNameSpecifier class.
  255.   mutable llvm::FoldingSet<NestedNameSpecifier> NestedNameSpecifiers;
  256.   mutable NestedNameSpecifier *GlobalNestedNameSpecifier = nullptr;
  257.  
  258.   /// A cache mapping from RecordDecls to ASTRecordLayouts.
  259.   ///
  260.   /// This is lazily created.  This is intentionally not serialized.
  261.   mutable llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>
  262.     ASTRecordLayouts;
  263.   mutable llvm::DenseMap<const ObjCContainerDecl*, const ASTRecordLayout*>
  264.     ObjCLayouts;
  265.  
  266.   /// A cache from types to size and alignment information.
  267.   using TypeInfoMap = llvm::DenseMap<const Type *, struct TypeInfo>;
  268.   mutable TypeInfoMap MemoizedTypeInfo;
  269.  
  270.   /// A cache from types to unadjusted alignment information. Only ARM and
  271.   /// AArch64 targets need this information, keeping it separate prevents
  272.   /// imposing overhead on TypeInfo size.
  273.   using UnadjustedAlignMap = llvm::DenseMap<const Type *, unsigned>;
  274.   mutable UnadjustedAlignMap MemoizedUnadjustedAlign;
  275.  
  276.   /// A cache mapping from CXXRecordDecls to key functions.
  277.   llvm::DenseMap<const CXXRecordDecl*, LazyDeclPtr> KeyFunctions;
  278.  
  279.   /// Mapping from ObjCContainers to their ObjCImplementations.
  280.   llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*> ObjCImpls;
  281.  
  282.   /// Mapping from ObjCMethod to its duplicate declaration in the same
  283.   /// interface.
  284.   llvm::DenseMap<const ObjCMethodDecl*,const ObjCMethodDecl*> ObjCMethodRedecls;
  285.  
  286.   /// Mapping from __block VarDecls to BlockVarCopyInit.
  287.   llvm::DenseMap<const VarDecl *, BlockVarCopyInit> BlockVarCopyInits;
  288.  
  289.   /// Mapping from GUIDs to the corresponding MSGuidDecl.
  290.   mutable llvm::FoldingSet<MSGuidDecl> MSGuidDecls;
  291.  
  292.   /// Mapping from APValues to the corresponding UnnamedGlobalConstantDecl.
  293.   mutable llvm::FoldingSet<UnnamedGlobalConstantDecl>
  294.       UnnamedGlobalConstantDecls;
  295.  
  296.   /// Mapping from APValues to the corresponding TemplateParamObjects.
  297.   mutable llvm::FoldingSet<TemplateParamObjectDecl> TemplateParamObjectDecls;
  298.  
  299.   /// A cache mapping a string value to a StringLiteral object with the same
  300.   /// value.
  301.   ///
  302.   /// This is lazily created.  This is intentionally not serialized.
  303.   mutable llvm::StringMap<StringLiteral *> StringLiteralCache;
  304.  
  305.   /// MD5 hash of CUID. It is calculated when first used and cached by this
  306.   /// data member.
  307.   mutable std::string CUIDHash;
  308.  
  309.   /// Representation of a "canonical" template template parameter that
  310.   /// is used in canonical template names.
  311.   class CanonicalTemplateTemplateParm : public llvm::FoldingSetNode {
  312.     TemplateTemplateParmDecl *Parm;
  313.  
  314.   public:
  315.     CanonicalTemplateTemplateParm(TemplateTemplateParmDecl *Parm)
  316.         : Parm(Parm) {}
  317.  
  318.     TemplateTemplateParmDecl *getParam() const { return Parm; }
  319.  
  320.     void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &C) {
  321.       Profile(ID, C, Parm);
  322.     }
  323.  
  324.     static void Profile(llvm::FoldingSetNodeID &ID,
  325.                         const ASTContext &C,
  326.                         TemplateTemplateParmDecl *Parm);
  327.   };
  328.   mutable llvm::ContextualFoldingSet<CanonicalTemplateTemplateParm,
  329.                                      const ASTContext&>
  330.     CanonTemplateTemplateParms;
  331.  
  332.   TemplateTemplateParmDecl *
  333.     getCanonicalTemplateTemplateParmDecl(TemplateTemplateParmDecl *TTP) const;
  334.  
  335.   /// The typedef for the __int128_t type.
  336.   mutable TypedefDecl *Int128Decl = nullptr;
  337.  
  338.   /// The typedef for the __uint128_t type.
  339.   mutable TypedefDecl *UInt128Decl = nullptr;
  340.  
  341.   /// The typedef for the target specific predefined
  342.   /// __builtin_va_list type.
  343.   mutable TypedefDecl *BuiltinVaListDecl = nullptr;
  344.  
  345.   /// The typedef for the predefined \c __builtin_ms_va_list type.
  346.   mutable TypedefDecl *BuiltinMSVaListDecl = nullptr;
  347.  
  348.   /// The typedef for the predefined \c id type.
  349.   mutable TypedefDecl *ObjCIdDecl = nullptr;
  350.  
  351.   /// The typedef for the predefined \c SEL type.
  352.   mutable TypedefDecl *ObjCSelDecl = nullptr;
  353.  
  354.   /// The typedef for the predefined \c Class type.
  355.   mutable TypedefDecl *ObjCClassDecl = nullptr;
  356.  
  357.   /// The typedef for the predefined \c Protocol class in Objective-C.
  358.   mutable ObjCInterfaceDecl *ObjCProtocolClassDecl = nullptr;
  359.  
  360.   /// The typedef for the predefined 'BOOL' type.
  361.   mutable TypedefDecl *BOOLDecl = nullptr;
  362.  
  363.   // Typedefs which may be provided defining the structure of Objective-C
  364.   // pseudo-builtins
  365.   QualType ObjCIdRedefinitionType;
  366.   QualType ObjCClassRedefinitionType;
  367.   QualType ObjCSelRedefinitionType;
  368.  
  369.   /// The identifier 'bool'.
  370.   mutable IdentifierInfo *BoolName = nullptr;
  371.  
  372.   /// The identifier 'NSObject'.
  373.   mutable IdentifierInfo *NSObjectName = nullptr;
  374.  
  375.   /// The identifier 'NSCopying'.
  376.   IdentifierInfo *NSCopyingName = nullptr;
  377.  
  378.   /// The identifier '__make_integer_seq'.
  379.   mutable IdentifierInfo *MakeIntegerSeqName = nullptr;
  380.  
  381.   /// The identifier '__type_pack_element'.
  382.   mutable IdentifierInfo *TypePackElementName = nullptr;
  383.  
  384.   QualType ObjCConstantStringType;
  385.   mutable RecordDecl *CFConstantStringTagDecl = nullptr;
  386.   mutable TypedefDecl *CFConstantStringTypeDecl = nullptr;
  387.  
  388.   mutable QualType ObjCSuperType;
  389.  
  390.   QualType ObjCNSStringType;
  391.  
  392.   /// The typedef declaration for the Objective-C "instancetype" type.
  393.   TypedefDecl *ObjCInstanceTypeDecl = nullptr;
  394.  
  395.   /// The type for the C FILE type.
  396.   TypeDecl *FILEDecl = nullptr;
  397.  
  398.   /// The type for the C jmp_buf type.
  399.   TypeDecl *jmp_bufDecl = nullptr;
  400.  
  401.   /// The type for the C sigjmp_buf type.
  402.   TypeDecl *sigjmp_bufDecl = nullptr;
  403.  
  404.   /// The type for the C ucontext_t type.
  405.   TypeDecl *ucontext_tDecl = nullptr;
  406.  
  407.   /// Type for the Block descriptor for Blocks CodeGen.
  408.   ///
  409.   /// Since this is only used for generation of debug info, it is not
  410.   /// serialized.
  411.   mutable RecordDecl *BlockDescriptorType = nullptr;
  412.  
  413.   /// Type for the Block descriptor for Blocks CodeGen.
  414.   ///
  415.   /// Since this is only used for generation of debug info, it is not
  416.   /// serialized.
  417.   mutable RecordDecl *BlockDescriptorExtendedType = nullptr;
  418.  
  419.   /// Declaration for the CUDA cudaConfigureCall function.
  420.   FunctionDecl *cudaConfigureCallDecl = nullptr;
  421.  
  422.   /// Keeps track of all declaration attributes.
  423.   ///
  424.   /// Since so few decls have attrs, we keep them in a hash map instead of
  425.   /// wasting space in the Decl class.
  426.   llvm::DenseMap<const Decl*, AttrVec*> DeclAttrs;
  427.  
  428.   /// A mapping from non-redeclarable declarations in modules that were
  429.   /// merged with other declarations to the canonical declaration that they were
  430.   /// merged into.
  431.   llvm::DenseMap<Decl*, Decl*> MergedDecls;
  432.  
  433.   /// A mapping from a defining declaration to a list of modules (other
  434.   /// than the owning module of the declaration) that contain merged
  435.   /// definitions of that entity.
  436.   llvm::DenseMap<NamedDecl*, llvm::TinyPtrVector<Module*>> MergedDefModules;
  437.  
  438.   /// Initializers for a module, in order. Each Decl will be either
  439.   /// something that has a semantic effect on startup (such as a variable with
  440.   /// a non-constant initializer), or an ImportDecl (which recursively triggers
  441.   /// initialization of another module).
  442.   struct PerModuleInitializers {
  443.     llvm::SmallVector<Decl*, 4> Initializers;
  444.     llvm::SmallVector<uint32_t, 4> LazyInitializers;
  445.  
  446.     void resolve(ASTContext &Ctx);
  447.   };
  448.   llvm::DenseMap<Module*, PerModuleInitializers*> ModuleInitializers;
  449.  
  450.   /// For module code-gen cases, this is the top-level module we are building.
  451.   Module *TopLevelModule = nullptr;
  452.  
  453.   static constexpr unsigned ConstantArrayTypesLog2InitSize = 8;
  454.   static constexpr unsigned GeneralTypesLog2InitSize = 9;
  455.   static constexpr unsigned FunctionProtoTypesLog2InitSize = 12;
  456.  
  457.   ASTContext &this_() { return *this; }
  458.  
  459. public:
  460.   /// A type synonym for the TemplateOrInstantiation mapping.
  461.   using TemplateOrSpecializationInfo =
  462.       llvm::PointerUnion<VarTemplateDecl *, MemberSpecializationInfo *>;
  463.  
  464. private:
  465.   friend class ASTDeclReader;
  466.   friend class ASTReader;
  467.   friend class ASTWriter;
  468.   template <class> friend class serialization::AbstractTypeReader;
  469.   friend class CXXRecordDecl;
  470.   friend class IncrementalParser;
  471.  
  472.   /// A mapping to contain the template or declaration that
  473.   /// a variable declaration describes or was instantiated from,
  474.   /// respectively.
  475.   ///
  476.   /// For non-templates, this value will be NULL. For variable
  477.   /// declarations that describe a variable template, this will be a
  478.   /// pointer to a VarTemplateDecl. For static data members
  479.   /// of class template specializations, this will be the
  480.   /// MemberSpecializationInfo referring to the member variable that was
  481.   /// instantiated or specialized. Thus, the mapping will keep track of
  482.   /// the static data member templates from which static data members of
  483.   /// class template specializations were instantiated.
  484.   ///
  485.   /// Given the following example:
  486.   ///
  487.   /// \code
  488.   /// template<typename T>
  489.   /// struct X {
  490.   ///   static T value;
  491.   /// };
  492.   ///
  493.   /// template<typename T>
  494.   ///   T X<T>::value = T(17);
  495.   ///
  496.   /// int *x = &X<int>::value;
  497.   /// \endcode
  498.   ///
  499.   /// This mapping will contain an entry that maps from the VarDecl for
  500.   /// X<int>::value to the corresponding VarDecl for X<T>::value (within the
  501.   /// class template X) and will be marked TSK_ImplicitInstantiation.
  502.   llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>
  503.   TemplateOrInstantiation;
  504.  
  505.   /// Keeps track of the declaration from which a using declaration was
  506.   /// created during instantiation.
  507.   ///
  508.   /// The source and target declarations are always a UsingDecl, an
  509.   /// UnresolvedUsingValueDecl, or an UnresolvedUsingTypenameDecl.
  510.   ///
  511.   /// For example:
  512.   /// \code
  513.   /// template<typename T>
  514.   /// struct A {
  515.   ///   void f();
  516.   /// };
  517.   ///
  518.   /// template<typename T>
  519.   /// struct B : A<T> {
  520.   ///   using A<T>::f;
  521.   /// };
  522.   ///
  523.   /// template struct B<int>;
  524.   /// \endcode
  525.   ///
  526.   /// This mapping will contain an entry that maps from the UsingDecl in
  527.   /// B<int> to the UnresolvedUsingDecl in B<T>.
  528.   llvm::DenseMap<NamedDecl *, NamedDecl *> InstantiatedFromUsingDecl;
  529.  
  530.   /// Like InstantiatedFromUsingDecl, but for using-enum-declarations. Maps
  531.   /// from the instantiated using-enum to the templated decl from whence it
  532.   /// came.
  533.   /// Note that using-enum-declarations cannot be dependent and
  534.   /// thus will never be instantiated from an "unresolved"
  535.   /// version thereof (as with using-declarations), so each mapping is from
  536.   /// a (resolved) UsingEnumDecl to a (resolved) UsingEnumDecl.
  537.   llvm::DenseMap<UsingEnumDecl *, UsingEnumDecl *>
  538.       InstantiatedFromUsingEnumDecl;
  539.  
  540.   /// Simlarly maps instantiated UsingShadowDecls to their origin.
  541.   llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>
  542.     InstantiatedFromUsingShadowDecl;
  543.  
  544.   llvm::DenseMap<FieldDecl *, FieldDecl *> InstantiatedFromUnnamedFieldDecl;
  545.  
  546.   /// Mapping that stores the methods overridden by a given C++
  547.   /// member function.
  548.   ///
  549.   /// Since most C++ member functions aren't virtual and therefore
  550.   /// don't override anything, we store the overridden functions in
  551.   /// this map on the side rather than within the CXXMethodDecl structure.
  552.   using CXXMethodVector = llvm::TinyPtrVector<const CXXMethodDecl *>;
  553.   llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector> OverriddenMethods;
  554.  
  555.   /// Mapping from each declaration context to its corresponding
  556.   /// mangling numbering context (used for constructs like lambdas which
  557.   /// need to be consistently numbered for the mangler).
  558.   llvm::DenseMap<const DeclContext *, std::unique_ptr<MangleNumberingContext>>
  559.       MangleNumberingContexts;
  560.   llvm::DenseMap<const Decl *, std::unique_ptr<MangleNumberingContext>>
  561.       ExtraMangleNumberingContexts;
  562.  
  563.   /// Side-table of mangling numbers for declarations which rarely
  564.   /// need them (like static local vars).
  565.   llvm::MapVector<const NamedDecl *, unsigned> MangleNumbers;
  566.   llvm::MapVector<const VarDecl *, unsigned> StaticLocalNumbers;
  567.   /// Mapping the associated device lambda mangling number if present.
  568.   mutable llvm::DenseMap<const CXXRecordDecl *, unsigned>
  569.       DeviceLambdaManglingNumbers;
  570.  
  571.   /// Mapping that stores parameterIndex values for ParmVarDecls when
  572.   /// that value exceeds the bitfield size of ParmVarDeclBits.ParameterIndex.
  573.   using ParameterIndexTable = llvm::DenseMap<const VarDecl *, unsigned>;
  574.   ParameterIndexTable ParamIndices;
  575.  
  576.   ImportDecl *FirstLocalImport = nullptr;
  577.   ImportDecl *LastLocalImport = nullptr;
  578.  
  579.   TranslationUnitDecl *TUDecl = nullptr;
  580.   mutable ExternCContextDecl *ExternCContext = nullptr;
  581.   mutable BuiltinTemplateDecl *MakeIntegerSeqDecl = nullptr;
  582.   mutable BuiltinTemplateDecl *TypePackElementDecl = nullptr;
  583.  
  584.   /// The associated SourceManager object.
  585.   SourceManager &SourceMgr;
  586.  
  587.   /// The language options used to create the AST associated with
  588.   ///  this ASTContext object.
  589.   LangOptions &LangOpts;
  590.  
  591.   /// NoSanitizeList object that is used by sanitizers to decide which
  592.   /// entities should not be instrumented.
  593.   std::unique_ptr<NoSanitizeList> NoSanitizeL;
  594.  
  595.   /// Function filtering mechanism to determine whether a given function
  596.   /// should be imbued with the XRay "always" or "never" attributes.
  597.   std::unique_ptr<XRayFunctionFilter> XRayFilter;
  598.  
  599.   /// ProfileList object that is used by the profile instrumentation
  600.   /// to decide which entities should be instrumented.
  601.   std::unique_ptr<ProfileList> ProfList;
  602.  
  603.   /// The allocator used to create AST objects.
  604.   ///
  605.   /// AST objects are never destructed; rather, all memory associated with the
  606.   /// AST objects will be released when the ASTContext itself is destroyed.
  607.   mutable llvm::BumpPtrAllocator BumpAlloc;
  608.  
  609.   /// Allocator for partial diagnostics.
  610.   PartialDiagnostic::DiagStorageAllocator DiagAllocator;
  611.  
  612.   /// The current C++ ABI.
  613.   std::unique_ptr<CXXABI> ABI;
  614.   CXXABI *createCXXABI(const TargetInfo &T);
  615.  
  616.   /// Address space map mangling must be used with language specific
  617.   /// address spaces (e.g. OpenCL/CUDA)
  618.   bool AddrSpaceMapMangling;
  619.  
  620.   const TargetInfo *Target = nullptr;
  621.   const TargetInfo *AuxTarget = nullptr;
  622.   clang::PrintingPolicy PrintingPolicy;
  623.   std::unique_ptr<interp::Context> InterpContext;
  624.   std::unique_ptr<ParentMapContext> ParentMapCtx;
  625.  
  626.   /// Keeps track of the deallocated DeclListNodes for future reuse.
  627.   DeclListNode *ListNodeFreeList = nullptr;
  628.  
  629. public:
  630.   IdentifierTable &Idents;
  631.   SelectorTable &Selectors;
  632.   Builtin::Context &BuiltinInfo;
  633.   const TranslationUnitKind TUKind;
  634.   mutable DeclarationNameTable DeclarationNames;
  635.   IntrusiveRefCntPtr<ExternalASTSource> ExternalSource;
  636.   ASTMutationListener *Listener = nullptr;
  637.  
  638.   /// Returns the clang bytecode interpreter context.
  639.   interp::Context &getInterpContext();
  640.  
  641.   struct CUDAConstantEvalContext {
  642.     /// Do not allow wrong-sided variables in constant expressions.
  643.     bool NoWrongSidedVars = false;
  644.   } CUDAConstantEvalCtx;
  645.   struct CUDAConstantEvalContextRAII {
  646.     ASTContext &Ctx;
  647.     CUDAConstantEvalContext SavedCtx;
  648.     CUDAConstantEvalContextRAII(ASTContext &Ctx_, bool NoWrongSidedVars)
  649.         : Ctx(Ctx_), SavedCtx(Ctx_.CUDAConstantEvalCtx) {
  650.       Ctx_.CUDAConstantEvalCtx.NoWrongSidedVars = NoWrongSidedVars;
  651.     }
  652.     ~CUDAConstantEvalContextRAII() { Ctx.CUDAConstantEvalCtx = SavedCtx; }
  653.   };
  654.  
  655.   /// Returns the dynamic AST node parent map context.
  656.   ParentMapContext &getParentMapContext();
  657.  
  658.   // A traversal scope limits the parts of the AST visible to certain analyses.
  659.   // RecursiveASTVisitor only visits specified children of TranslationUnitDecl.
  660.   // getParents() will only observe reachable parent edges.
  661.   //
  662.   // The scope is defined by a set of "top-level" declarations which will be
  663.   // visible under the TranslationUnitDecl.
  664.   // Initially, it is the entire TU, represented by {getTranslationUnitDecl()}.
  665.   //
  666.   // After setTraversalScope({foo, bar}), the exposed AST looks like:
  667.   // TranslationUnitDecl
  668.   //  - foo
  669.   //    - ...
  670.   //  - bar
  671.   //    - ...
  672.   // All other siblings of foo and bar are pruned from the tree.
  673.   // (However they are still accessible via TranslationUnitDecl->decls())
  674.   //
  675.   // Changing the scope clears the parent cache, which is expensive to rebuild.
  676.   std::vector<Decl *> getTraversalScope() const { return TraversalScope; }
  677.   void setTraversalScope(const std::vector<Decl *> &);
  678.  
  679.   /// Forwards to get node parents from the ParentMapContext. New callers should
  680.   /// use ParentMapContext::getParents() directly.
  681.   template <typename NodeT> DynTypedNodeList getParents(const NodeT &Node);
  682.  
  683.   const clang::PrintingPolicy &getPrintingPolicy() const {
  684.     return PrintingPolicy;
  685.   }
  686.  
  687.   void setPrintingPolicy(const clang::PrintingPolicy &Policy) {
  688.     PrintingPolicy = Policy;
  689.   }
  690.  
  691.   SourceManager& getSourceManager() { return SourceMgr; }
  692.   const SourceManager& getSourceManager() const { return SourceMgr; }
  693.  
  694.   // Cleans up some of the data structures. This allows us to do cleanup
  695.   // normally done in the destructor earlier. Renders much of the ASTContext
  696.   // unusable, mostly the actual AST nodes, so should be called when we no
  697.   // longer need access to the AST.
  698.   void cleanup();
  699.  
  700.   llvm::BumpPtrAllocator &getAllocator() const {
  701.     return BumpAlloc;
  702.   }
  703.  
  704.   void *Allocate(size_t Size, unsigned Align = 8) const {
  705.     return BumpAlloc.Allocate(Size, Align);
  706.   }
  707.   template <typename T> T *Allocate(size_t Num = 1) const {
  708.     return static_cast<T *>(Allocate(Num * sizeof(T), alignof(T)));
  709.   }
  710.   void Deallocate(void *Ptr) const {}
  711.  
  712.   /// Allocates a \c DeclListNode or returns one from the \c ListNodeFreeList
  713.   /// pool.
  714.   DeclListNode *AllocateDeclListNode(clang::NamedDecl *ND) {
  715.     if (DeclListNode *Alloc = ListNodeFreeList) {
  716.       ListNodeFreeList = Alloc->Rest.dyn_cast<DeclListNode*>();
  717.       Alloc->D = ND;
  718.       Alloc->Rest = nullptr;
  719.       return Alloc;
  720.     }
  721.     return new (*this) DeclListNode(ND);
  722.   }
  723.   /// Deallcates a \c DeclListNode by returning it to the \c ListNodeFreeList
  724.   /// pool.
  725.   void DeallocateDeclListNode(DeclListNode *N) {
  726.     N->Rest = ListNodeFreeList;
  727.     ListNodeFreeList = N;
  728.   }
  729.  
  730.   /// Return the total amount of physical memory allocated for representing
  731.   /// AST nodes and type information.
  732.   size_t getASTAllocatedMemory() const {
  733.     return BumpAlloc.getTotalMemory();
  734.   }
  735.  
  736.   /// Return the total memory used for various side tables.
  737.   size_t getSideTableAllocatedMemory() const;
  738.  
  739.   PartialDiagnostic::DiagStorageAllocator &getDiagAllocator() {
  740.     return DiagAllocator;
  741.   }
  742.  
  743.   const TargetInfo &getTargetInfo() const { return *Target; }
  744.   const TargetInfo *getAuxTargetInfo() const { return AuxTarget; }
  745.  
  746.   /// getIntTypeForBitwidth -
  747.   /// sets integer QualTy according to specified details:
  748.   /// bitwidth, signed/unsigned.
  749.   /// Returns empty type if there is no appropriate target types.
  750.   QualType getIntTypeForBitwidth(unsigned DestWidth,
  751.                                  unsigned Signed) const;
  752.  
  753.   /// getRealTypeForBitwidth -
  754.   /// sets floating point QualTy according to specified bitwidth.
  755.   /// Returns empty type if there is no appropriate target types.
  756.   QualType getRealTypeForBitwidth(unsigned DestWidth,
  757.                                   FloatModeKind ExplicitType) const;
  758.  
  759.   bool AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const;
  760.  
  761.   const LangOptions& getLangOpts() const { return LangOpts; }
  762.  
  763.   // If this condition is false, typo correction must be performed eagerly
  764.   // rather than delayed in many places, as it makes use of dependent types.
  765.   // the condition is false for clang's C-only codepath, as it doesn't support
  766.   // dependent types yet.
  767.   bool isDependenceAllowed() const {
  768.     return LangOpts.CPlusPlus || LangOpts.RecoveryAST;
  769.   }
  770.  
  771.   const NoSanitizeList &getNoSanitizeList() const { return *NoSanitizeL; }
  772.  
  773.   const XRayFunctionFilter &getXRayFilter() const {
  774.     return *XRayFilter;
  775.   }
  776.  
  777.   const ProfileList &getProfileList() const { return *ProfList; }
  778.  
  779.   DiagnosticsEngine &getDiagnostics() const;
  780.  
  781.   FullSourceLoc getFullLoc(SourceLocation Loc) const {
  782.     return FullSourceLoc(Loc,SourceMgr);
  783.   }
  784.  
  785.   /// Return the C++ ABI kind that should be used. The C++ ABI can be overriden
  786.   /// at compile time with `-fc++-abi=`. If this is not provided, we instead use
  787.   /// the default ABI set by the target.
  788.   TargetCXXABI::Kind getCXXABIKind() const;
  789.  
  790.   /// All comments in this translation unit.
  791.   RawCommentList Comments;
  792.  
  793.   /// True if comments are already loaded from ExternalASTSource.
  794.   mutable bool CommentsLoaded = false;
  795.  
  796.   /// Mapping from declaration to directly attached comment.
  797.   ///
  798.   /// Raw comments are owned by Comments list.  This mapping is populated
  799.   /// lazily.
  800.   mutable llvm::DenseMap<const Decl *, const RawComment *> DeclRawComments;
  801.  
  802.   /// Mapping from canonical declaration to the first redeclaration in chain
  803.   /// that has a comment attached.
  804.   ///
  805.   /// Raw comments are owned by Comments list.  This mapping is populated
  806.   /// lazily.
  807.   mutable llvm::DenseMap<const Decl *, const Decl *> RedeclChainComments;
  808.  
  809.   /// Keeps track of redeclaration chains that don't have any comment attached.
  810.   /// Mapping from canonical declaration to redeclaration chain that has no
  811.   /// comments attached to any redeclaration. Specifically it's mapping to
  812.   /// the last redeclaration we've checked.
  813.   ///
  814.   /// Shall not contain declarations that have comments attached to any
  815.   /// redeclaration in their chain.
  816.   mutable llvm::DenseMap<const Decl *, const Decl *> CommentlessRedeclChains;
  817.  
  818.   /// Mapping from declarations to parsed comments attached to any
  819.   /// redeclaration.
  820.   mutable llvm::DenseMap<const Decl *, comments::FullComment *> ParsedComments;
  821.  
  822.   /// Attaches \p Comment to \p OriginalD and to its redeclaration chain
  823.   /// and removes the redeclaration chain from the set of commentless chains.
  824.   ///
  825.   /// Don't do anything if a comment has already been attached to \p OriginalD
  826.   /// or its redeclaration chain.
  827.   void cacheRawCommentForDecl(const Decl &OriginalD,
  828.                               const RawComment &Comment) const;
  829.  
  830.   /// \returns searches \p CommentsInFile for doc comment for \p D.
  831.   ///
  832.   /// \p RepresentativeLocForDecl is used as a location for searching doc
  833.   /// comments. \p CommentsInFile is a mapping offset -> comment of files in the
  834.   /// same file where \p RepresentativeLocForDecl is.
  835.   RawComment *getRawCommentForDeclNoCacheImpl(
  836.       const Decl *D, const SourceLocation RepresentativeLocForDecl,
  837.       const std::map<unsigned, RawComment *> &CommentsInFile) const;
  838.  
  839.   /// Return the documentation comment attached to a given declaration,
  840.   /// without looking into cache.
  841.   RawComment *getRawCommentForDeclNoCache(const Decl *D) const;
  842.  
  843. public:
  844.   void addComment(const RawComment &RC);
  845.  
  846.   /// Return the documentation comment attached to a given declaration.
  847.   /// Returns nullptr if no comment is attached.
  848.   ///
  849.   /// \param OriginalDecl if not nullptr, is set to declaration AST node that
  850.   /// had the comment, if the comment we found comes from a redeclaration.
  851.   const RawComment *
  852.   getRawCommentForAnyRedecl(const Decl *D,
  853.                             const Decl **OriginalDecl = nullptr) const;
  854.  
  855.   /// Searches existing comments for doc comments that should be attached to \p
  856.   /// Decls. If any doc comment is found, it is parsed.
  857.   ///
  858.   /// Requirement: All \p Decls are in the same file.
  859.   ///
  860.   /// If the last comment in the file is already attached we assume
  861.   /// there are not comments left to be attached to \p Decls.
  862.   void attachCommentsToJustParsedDecls(ArrayRef<Decl *> Decls,
  863.                                        const Preprocessor *PP);
  864.  
  865.   /// Return parsed documentation comment attached to a given declaration.
  866.   /// Returns nullptr if no comment is attached.
  867.   ///
  868.   /// \param PP the Preprocessor used with this TU.  Could be nullptr if
  869.   /// preprocessor is not available.
  870.   comments::FullComment *getCommentForDecl(const Decl *D,
  871.                                            const Preprocessor *PP) const;
  872.  
  873.   /// Return parsed documentation comment attached to a given declaration.
  874.   /// Returns nullptr if no comment is attached. Does not look at any
  875.   /// redeclarations of the declaration.
  876.   comments::FullComment *getLocalCommentForDeclUncached(const Decl *D) const;
  877.  
  878.   comments::FullComment *cloneFullComment(comments::FullComment *FC,
  879.                                          const Decl *D) const;
  880.  
  881. private:
  882.   mutable comments::CommandTraits CommentCommandTraits;
  883.  
  884.   /// Iterator that visits import declarations.
  885.   class import_iterator {
  886.     ImportDecl *Import = nullptr;
  887.  
  888.   public:
  889.     using value_type = ImportDecl *;
  890.     using reference = ImportDecl *;
  891.     using pointer = ImportDecl *;
  892.     using difference_type = int;
  893.     using iterator_category = std::forward_iterator_tag;
  894.  
  895.     import_iterator() = default;
  896.     explicit import_iterator(ImportDecl *Import) : Import(Import) {}
  897.  
  898.     reference operator*() const { return Import; }
  899.     pointer operator->() const { return Import; }
  900.  
  901.     import_iterator &operator++() {
  902.       Import = ASTContext::getNextLocalImport(Import);
  903.       return *this;
  904.     }
  905.  
  906.     import_iterator operator++(int) {
  907.       import_iterator Other(*this);
  908.       ++(*this);
  909.       return Other;
  910.     }
  911.  
  912.     friend bool operator==(import_iterator X, import_iterator Y) {
  913.       return X.Import == Y.Import;
  914.     }
  915.  
  916.     friend bool operator!=(import_iterator X, import_iterator Y) {
  917.       return X.Import != Y.Import;
  918.     }
  919.   };
  920.  
  921. public:
  922.   comments::CommandTraits &getCommentCommandTraits() const {
  923.     return CommentCommandTraits;
  924.   }
  925.  
  926.   /// Retrieve the attributes for the given declaration.
  927.   AttrVec& getDeclAttrs(const Decl *D);
  928.  
  929.   /// Erase the attributes corresponding to the given declaration.
  930.   void eraseDeclAttrs(const Decl *D);
  931.  
  932.   /// If this variable is an instantiated static data member of a
  933.   /// class template specialization, returns the templated static data member
  934.   /// from which it was instantiated.
  935.   // FIXME: Remove ?
  936.   MemberSpecializationInfo *getInstantiatedFromStaticDataMember(
  937.                                                            const VarDecl *Var);
  938.  
  939.   /// Note that the static data member \p Inst is an instantiation of
  940.   /// the static data member template \p Tmpl of a class template.
  941.   void setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
  942.                                            TemplateSpecializationKind TSK,
  943.                         SourceLocation PointOfInstantiation = SourceLocation());
  944.  
  945.   TemplateOrSpecializationInfo
  946.   getTemplateOrSpecializationInfo(const VarDecl *Var);
  947.  
  948.   void setTemplateOrSpecializationInfo(VarDecl *Inst,
  949.                                        TemplateOrSpecializationInfo TSI);
  950.  
  951.   /// If the given using decl \p Inst is an instantiation of
  952.   /// another (possibly unresolved) using decl, return it.
  953.   NamedDecl *getInstantiatedFromUsingDecl(NamedDecl *Inst);
  954.  
  955.   /// Remember that the using decl \p Inst is an instantiation
  956.   /// of the using decl \p Pattern of a class template.
  957.   void setInstantiatedFromUsingDecl(NamedDecl *Inst, NamedDecl *Pattern);
  958.  
  959.   /// If the given using-enum decl \p Inst is an instantiation of
  960.   /// another using-enum decl, return it.
  961.   UsingEnumDecl *getInstantiatedFromUsingEnumDecl(UsingEnumDecl *Inst);
  962.  
  963.   /// Remember that the using enum decl \p Inst is an instantiation
  964.   /// of the using enum decl \p Pattern of a class template.
  965.   void setInstantiatedFromUsingEnumDecl(UsingEnumDecl *Inst,
  966.                                         UsingEnumDecl *Pattern);
  967.  
  968.   UsingShadowDecl *getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst);
  969.   void setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
  970.                                           UsingShadowDecl *Pattern);
  971.  
  972.   FieldDecl *getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field);
  973.  
  974.   void setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst, FieldDecl *Tmpl);
  975.  
  976.   // Access to the set of methods overridden by the given C++ method.
  977.   using overridden_cxx_method_iterator = CXXMethodVector::const_iterator;
  978.   overridden_cxx_method_iterator
  979.   overridden_methods_begin(const CXXMethodDecl *Method) const;
  980.  
  981.   overridden_cxx_method_iterator
  982.   overridden_methods_end(const CXXMethodDecl *Method) const;
  983.  
  984.   unsigned overridden_methods_size(const CXXMethodDecl *Method) const;
  985.  
  986.   using overridden_method_range =
  987.       llvm::iterator_range<overridden_cxx_method_iterator>;
  988.  
  989.   overridden_method_range overridden_methods(const CXXMethodDecl *Method) const;
  990.  
  991.   /// Note that the given C++ \p Method overrides the given \p
  992.   /// Overridden method.
  993.   void addOverriddenMethod(const CXXMethodDecl *Method,
  994.                            const CXXMethodDecl *Overridden);
  995.  
  996.   /// Return C++ or ObjC overridden methods for the given \p Method.
  997.   ///
  998.   /// An ObjC method is considered to override any method in the class's
  999.   /// base classes, its protocols, or its categories' protocols, that has
  1000.   /// the same selector and is of the same kind (class or instance).
  1001.   /// A method in an implementation is not considered as overriding the same
  1002.   /// method in the interface or its categories.
  1003.   void getOverriddenMethods(
  1004.                         const NamedDecl *Method,
  1005.                         SmallVectorImpl<const NamedDecl *> &Overridden) const;
  1006.  
  1007.   /// Notify the AST context that a new import declaration has been
  1008.   /// parsed or implicitly created within this translation unit.
  1009.   void addedLocalImportDecl(ImportDecl *Import);
  1010.  
  1011.   static ImportDecl *getNextLocalImport(ImportDecl *Import) {
  1012.     return Import->getNextLocalImport();
  1013.   }
  1014.  
  1015.   using import_range = llvm::iterator_range<import_iterator>;
  1016.  
  1017.   import_range local_imports() const {
  1018.     return import_range(import_iterator(FirstLocalImport), import_iterator());
  1019.   }
  1020.  
  1021.   Decl *getPrimaryMergedDecl(Decl *D) {
  1022.     Decl *Result = MergedDecls.lookup(D);
  1023.     return Result ? Result : D;
  1024.   }
  1025.   void setPrimaryMergedDecl(Decl *D, Decl *Primary) {
  1026.     MergedDecls[D] = Primary;
  1027.   }
  1028.  
  1029.   /// Note that the definition \p ND has been merged into module \p M,
  1030.   /// and should be visible whenever \p M is visible.
  1031.   void mergeDefinitionIntoModule(NamedDecl *ND, Module *M,
  1032.                                  bool NotifyListeners = true);
  1033.  
  1034.   /// Clean up the merged definition list. Call this if you might have
  1035.   /// added duplicates into the list.
  1036.   void deduplicateMergedDefinitonsFor(NamedDecl *ND);
  1037.  
  1038.   /// Get the additional modules in which the definition \p Def has
  1039.   /// been merged.
  1040.   ArrayRef<Module*> getModulesWithMergedDefinition(const NamedDecl *Def);
  1041.  
  1042.   /// Add a declaration to the list of declarations that are initialized
  1043.   /// for a module. This will typically be a global variable (with internal
  1044.   /// linkage) that runs module initializers, such as the iostream initializer,
  1045.   /// or an ImportDecl nominating another module that has initializers.
  1046.   void addModuleInitializer(Module *M, Decl *Init);
  1047.  
  1048.   void addLazyModuleInitializers(Module *M, ArrayRef<uint32_t> IDs);
  1049.  
  1050.   /// Get the initializations to perform when importing a module, if any.
  1051.   ArrayRef<Decl*> getModuleInitializers(Module *M);
  1052.  
  1053.   /// Set the (C++20) module we are building.
  1054.   void setModuleForCodeGen(Module *M) { TopLevelModule = M; }
  1055.  
  1056.   /// Get module under construction, nullptr if this is not a C++20 module.
  1057.   Module *getModuleForCodeGen() const { return TopLevelModule; }
  1058.  
  1059.   TranslationUnitDecl *getTranslationUnitDecl() const {
  1060.     return TUDecl->getMostRecentDecl();
  1061.   }
  1062.   void addTranslationUnitDecl() {
  1063.     assert(!TUDecl || TUKind == TU_Incremental);
  1064.     TranslationUnitDecl *NewTUDecl = TranslationUnitDecl::Create(*this);
  1065.     if (TraversalScope.empty() || TraversalScope.back() == TUDecl)
  1066.       TraversalScope = {NewTUDecl};
  1067.     if (TUDecl)
  1068.       NewTUDecl->setPreviousDecl(TUDecl);
  1069.     TUDecl = NewTUDecl;
  1070.   }
  1071.  
  1072.   ExternCContextDecl *getExternCContextDecl() const;
  1073.   BuiltinTemplateDecl *getMakeIntegerSeqDecl() const;
  1074.   BuiltinTemplateDecl *getTypePackElementDecl() const;
  1075.  
  1076.   // Builtin Types.
  1077.   CanQualType VoidTy;
  1078.   CanQualType BoolTy;
  1079.   CanQualType CharTy;
  1080.   CanQualType WCharTy;  // [C++ 3.9.1p5].
  1081.   CanQualType WideCharTy; // Same as WCharTy in C++, integer type in C99.
  1082.   CanQualType WIntTy;   // [C99 7.24.1], integer type unchanged by default promotions.
  1083.   CanQualType Char8Ty;  // [C++20 proposal]
  1084.   CanQualType Char16Ty; // [C++0x 3.9.1p5], integer type in C99.
  1085.   CanQualType Char32Ty; // [C++0x 3.9.1p5], integer type in C99.
  1086.   CanQualType SignedCharTy, ShortTy, IntTy, LongTy, LongLongTy, Int128Ty;
  1087.   CanQualType UnsignedCharTy, UnsignedShortTy, UnsignedIntTy, UnsignedLongTy;
  1088.   CanQualType UnsignedLongLongTy, UnsignedInt128Ty;
  1089.   CanQualType FloatTy, DoubleTy, LongDoubleTy, Float128Ty, Ibm128Ty;
  1090.   CanQualType ShortAccumTy, AccumTy,
  1091.       LongAccumTy;  // ISO/IEC JTC1 SC22 WG14 N1169 Extension
  1092.   CanQualType UnsignedShortAccumTy, UnsignedAccumTy, UnsignedLongAccumTy;
  1093.   CanQualType ShortFractTy, FractTy, LongFractTy;
  1094.   CanQualType UnsignedShortFractTy, UnsignedFractTy, UnsignedLongFractTy;
  1095.   CanQualType SatShortAccumTy, SatAccumTy, SatLongAccumTy;
  1096.   CanQualType SatUnsignedShortAccumTy, SatUnsignedAccumTy,
  1097.       SatUnsignedLongAccumTy;
  1098.   CanQualType SatShortFractTy, SatFractTy, SatLongFractTy;
  1099.   CanQualType SatUnsignedShortFractTy, SatUnsignedFractTy,
  1100.       SatUnsignedLongFractTy;
  1101.   CanQualType HalfTy; // [OpenCL 6.1.1.1], ARM NEON
  1102.   CanQualType BFloat16Ty;
  1103.   CanQualType Float16Ty; // C11 extension ISO/IEC TS 18661-3
  1104.   CanQualType VoidPtrTy, NullPtrTy;
  1105.   CanQualType DependentTy, OverloadTy, BoundMemberTy, UnknownAnyTy;
  1106.   CanQualType BuiltinFnTy;
  1107.   CanQualType PseudoObjectTy, ARCUnbridgedCastTy;
  1108.   CanQualType ObjCBuiltinIdTy, ObjCBuiltinClassTy, ObjCBuiltinSelTy;
  1109.   CanQualType ObjCBuiltinBoolTy;
  1110. #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
  1111.   CanQualType SingletonId;
  1112. #include "clang/Basic/OpenCLImageTypes.def"
  1113.   CanQualType OCLSamplerTy, OCLEventTy, OCLClkEventTy;
  1114.   CanQualType OCLQueueTy, OCLReserveIDTy;
  1115.   CanQualType IncompleteMatrixIdxTy;
  1116.   CanQualType OMPArraySectionTy, OMPArrayShapingTy, OMPIteratorTy;
  1117. #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
  1118.   CanQualType Id##Ty;
  1119. #include "clang/Basic/OpenCLExtensionTypes.def"
  1120. #define SVE_TYPE(Name, Id, SingletonId) \
  1121.   CanQualType SingletonId;
  1122. #include "clang/Basic/AArch64SVEACLETypes.def"
  1123. #define PPC_VECTOR_TYPE(Name, Id, Size) \
  1124.   CanQualType Id##Ty;
  1125. #include "clang/Basic/PPCTypes.def"
  1126. #define RVV_TYPE(Name, Id, SingletonId) \
  1127.   CanQualType SingletonId;
  1128. #include "clang/Basic/RISCVVTypes.def"
  1129.  
  1130.   // Types for deductions in C++0x [stmt.ranged]'s desugaring. Built on demand.
  1131.   mutable QualType AutoDeductTy;     // Deduction against 'auto'.
  1132.   mutable QualType AutoRRefDeductTy; // Deduction against 'auto &&'.
  1133.  
  1134.   // Decl used to help define __builtin_va_list for some targets.
  1135.   // The decl is built when constructing 'BuiltinVaListDecl'.
  1136.   mutable Decl *VaListTagDecl = nullptr;
  1137.  
  1138.   // Implicitly-declared type 'struct _GUID'.
  1139.   mutable TagDecl *MSGuidTagDecl = nullptr;
  1140.  
  1141.   /// Keep track of CUDA/HIP device-side variables ODR-used by host code.
  1142.   llvm::DenseSet<const VarDecl *> CUDADeviceVarODRUsedByHost;
  1143.  
  1144.   /// Keep track of CUDA/HIP external kernels or device variables ODR-used by
  1145.   /// host code.
  1146.   llvm::DenseSet<const ValueDecl *> CUDAExternalDeviceDeclODRUsedByHost;
  1147.  
  1148.   ASTContext(LangOptions &LOpts, SourceManager &SM, IdentifierTable &idents,
  1149.              SelectorTable &sels, Builtin::Context &builtins,
  1150.              TranslationUnitKind TUKind);
  1151.   ASTContext(const ASTContext &) = delete;
  1152.   ASTContext &operator=(const ASTContext &) = delete;
  1153.   ~ASTContext();
  1154.  
  1155.   /// Attach an external AST source to the AST context.
  1156.   ///
  1157.   /// The external AST source provides the ability to load parts of
  1158.   /// the abstract syntax tree as needed from some external storage,
  1159.   /// e.g., a precompiled header.
  1160.   void setExternalSource(IntrusiveRefCntPtr<ExternalASTSource> Source);
  1161.  
  1162.   /// Retrieve a pointer to the external AST source associated
  1163.   /// with this AST context, if any.
  1164.   ExternalASTSource *getExternalSource() const {
  1165.     return ExternalSource.get();
  1166.   }
  1167.  
  1168.   /// Attach an AST mutation listener to the AST context.
  1169.   ///
  1170.   /// The AST mutation listener provides the ability to track modifications to
  1171.   /// the abstract syntax tree entities committed after they were initially
  1172.   /// created.
  1173.   void setASTMutationListener(ASTMutationListener *Listener) {
  1174.     this->Listener = Listener;
  1175.   }
  1176.  
  1177.   /// Retrieve a pointer to the AST mutation listener associated
  1178.   /// with this AST context, if any.
  1179.   ASTMutationListener *getASTMutationListener() const { return Listener; }
  1180.  
  1181.   void PrintStats() const;
  1182.   const SmallVectorImpl<Type *>& getTypes() const { return Types; }
  1183.  
  1184.   BuiltinTemplateDecl *buildBuiltinTemplateDecl(BuiltinTemplateKind BTK,
  1185.                                                 const IdentifierInfo *II) const;
  1186.  
  1187.   /// Create a new implicit TU-level CXXRecordDecl or RecordDecl
  1188.   /// declaration.
  1189.   RecordDecl *buildImplicitRecord(StringRef Name,
  1190.                                   RecordDecl::TagKind TK = TTK_Struct) const;
  1191.  
  1192.   /// Create a new implicit TU-level typedef declaration.
  1193.   TypedefDecl *buildImplicitTypedef(QualType T, StringRef Name) const;
  1194.  
  1195.   /// Retrieve the declaration for the 128-bit signed integer type.
  1196.   TypedefDecl *getInt128Decl() const;
  1197.  
  1198.   /// Retrieve the declaration for the 128-bit unsigned integer type.
  1199.   TypedefDecl *getUInt128Decl() const;
  1200.  
  1201.   //===--------------------------------------------------------------------===//
  1202.   //                           Type Constructors
  1203.   //===--------------------------------------------------------------------===//
  1204.  
  1205. private:
  1206.   /// Return a type with extended qualifiers.
  1207.   QualType getExtQualType(const Type *Base, Qualifiers Quals) const;
  1208.  
  1209.   QualType getTypeDeclTypeSlow(const TypeDecl *Decl) const;
  1210.  
  1211.   QualType getPipeType(QualType T, bool ReadOnly) const;
  1212.  
  1213. public:
  1214.   /// Return the uniqued reference to the type for an address space
  1215.   /// qualified type with the specified type and address space.
  1216.   ///
  1217.   /// The resulting type has a union of the qualifiers from T and the address
  1218.   /// space. If T already has an address space specifier, it is silently
  1219.   /// replaced.
  1220.   QualType getAddrSpaceQualType(QualType T, LangAS AddressSpace) const;
  1221.  
  1222.   /// Remove any existing address space on the type and returns the type
  1223.   /// with qualifiers intact (or that's the idea anyway)
  1224.   ///
  1225.   /// The return type should be T with all prior qualifiers minus the address
  1226.   /// space.
  1227.   QualType removeAddrSpaceQualType(QualType T) const;
  1228.  
  1229.   /// Apply Objective-C protocol qualifiers to the given type.
  1230.   /// \param allowOnPointerType specifies if we can apply protocol
  1231.   /// qualifiers on ObjCObjectPointerType. It can be set to true when
  1232.   /// constructing the canonical type of a Objective-C type parameter.
  1233.   QualType applyObjCProtocolQualifiers(QualType type,
  1234.       ArrayRef<ObjCProtocolDecl *> protocols, bool &hasError,
  1235.       bool allowOnPointerType = false) const;
  1236.  
  1237.   /// Return the uniqued reference to the type for an Objective-C
  1238.   /// gc-qualified type.
  1239.   ///
  1240.   /// The resulting type has a union of the qualifiers from T and the gc
  1241.   /// attribute.
  1242.   QualType getObjCGCQualType(QualType T, Qualifiers::GC gcAttr) const;
  1243.  
  1244.   /// Remove the existing address space on the type if it is a pointer size
  1245.   /// address space and return the type with qualifiers intact.
  1246.   QualType removePtrSizeAddrSpace(QualType T) const;
  1247.  
  1248.   /// Return the uniqued reference to the type for a \c restrict
  1249.   /// qualified type.
  1250.   ///
  1251.   /// The resulting type has a union of the qualifiers from \p T and
  1252.   /// \c restrict.
  1253.   QualType getRestrictType(QualType T) const {
  1254.     return T.withFastQualifiers(Qualifiers::Restrict);
  1255.   }
  1256.  
  1257.   /// Return the uniqued reference to the type for a \c volatile
  1258.   /// qualified type.
  1259.   ///
  1260.   /// The resulting type has a union of the qualifiers from \p T and
  1261.   /// \c volatile.
  1262.   QualType getVolatileType(QualType T) const {
  1263.     return T.withFastQualifiers(Qualifiers::Volatile);
  1264.   }
  1265.  
  1266.   /// Return the uniqued reference to the type for a \c const
  1267.   /// qualified type.
  1268.   ///
  1269.   /// The resulting type has a union of the qualifiers from \p T and \c const.
  1270.   ///
  1271.   /// It can be reasonably expected that this will always be equivalent to
  1272.   /// calling T.withConst().
  1273.   QualType getConstType(QualType T) const { return T.withConst(); }
  1274.  
  1275.   /// Change the ExtInfo on a function type.
  1276.   const FunctionType *adjustFunctionType(const FunctionType *Fn,
  1277.                                          FunctionType::ExtInfo EInfo);
  1278.  
  1279.   /// Adjust the given function result type.
  1280.   CanQualType getCanonicalFunctionResultType(QualType ResultType) const;
  1281.  
  1282.   /// Change the result type of a function type once it is deduced.
  1283.   void adjustDeducedFunctionResultType(FunctionDecl *FD, QualType ResultType);
  1284.  
  1285.   /// Get a function type and produce the equivalent function type with the
  1286.   /// specified exception specification. Type sugar that can be present on a
  1287.   /// declaration of a function with an exception specification is permitted
  1288.   /// and preserved. Other type sugar (for instance, typedefs) is not.
  1289.   QualType getFunctionTypeWithExceptionSpec(
  1290.       QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI) const;
  1291.  
  1292.   /// Determine whether two function types are the same, ignoring
  1293.   /// exception specifications in cases where they're part of the type.
  1294.   bool hasSameFunctionTypeIgnoringExceptionSpec(QualType T, QualType U) const;
  1295.  
  1296.   /// Change the exception specification on a function once it is
  1297.   /// delay-parsed, instantiated, or computed.
  1298.   void adjustExceptionSpec(FunctionDecl *FD,
  1299.                            const FunctionProtoType::ExceptionSpecInfo &ESI,
  1300.                            bool AsWritten = false);
  1301.  
  1302.   /// Get a function type and produce the equivalent function type where
  1303.   /// pointer size address spaces in the return type and parameter tyeps are
  1304.   /// replaced with the default address space.
  1305.   QualType getFunctionTypeWithoutPtrSizes(QualType T);
  1306.  
  1307.   /// Determine whether two function types are the same, ignoring pointer sizes
  1308.   /// in the return type and parameter types.
  1309.   bool hasSameFunctionTypeIgnoringPtrSizes(QualType T, QualType U);
  1310.  
  1311.   /// Return the uniqued reference to the type for a complex
  1312.   /// number with the specified element type.
  1313.   QualType getComplexType(QualType T) const;
  1314.   CanQualType getComplexType(CanQualType T) const {
  1315.     return CanQualType::CreateUnsafe(getComplexType((QualType) T));
  1316.   }
  1317.  
  1318.   /// Return the uniqued reference to the type for a pointer to
  1319.   /// the specified type.
  1320.   QualType getPointerType(QualType T) const;
  1321.   CanQualType getPointerType(CanQualType T) const {
  1322.     return CanQualType::CreateUnsafe(getPointerType((QualType) T));
  1323.   }
  1324.  
  1325.   /// Return the uniqued reference to a type adjusted from the original
  1326.   /// type to a new type.
  1327.   QualType getAdjustedType(QualType Orig, QualType New) const;
  1328.   CanQualType getAdjustedType(CanQualType Orig, CanQualType New) const {
  1329.     return CanQualType::CreateUnsafe(
  1330.         getAdjustedType((QualType)Orig, (QualType)New));
  1331.   }
  1332.  
  1333.   /// Return the uniqued reference to the decayed version of the given
  1334.   /// type.  Can only be called on array and function types which decay to
  1335.   /// pointer types.
  1336.   QualType getDecayedType(QualType T) const;
  1337.   CanQualType getDecayedType(CanQualType T) const {
  1338.     return CanQualType::CreateUnsafe(getDecayedType((QualType) T));
  1339.   }
  1340.   /// Return the uniqued reference to a specified decay from the original
  1341.   /// type to the decayed type.
  1342.   QualType getDecayedType(QualType Orig, QualType Decayed) const;
  1343.  
  1344.   /// Return the uniqued reference to the atomic type for the specified
  1345.   /// type.
  1346.   QualType getAtomicType(QualType T) const;
  1347.  
  1348.   /// Return the uniqued reference to the type for a block of the
  1349.   /// specified type.
  1350.   QualType getBlockPointerType(QualType T) const;
  1351.  
  1352.   /// Gets the struct used to keep track of the descriptor for pointer to
  1353.   /// blocks.
  1354.   QualType getBlockDescriptorType() const;
  1355.  
  1356.   /// Return a read_only pipe type for the specified type.
  1357.   QualType getReadPipeType(QualType T) const;
  1358.  
  1359.   /// Return a write_only pipe type for the specified type.
  1360.   QualType getWritePipeType(QualType T) const;
  1361.  
  1362.   /// Return a bit-precise integer type with the specified signedness and bit
  1363.   /// count.
  1364.   QualType getBitIntType(bool Unsigned, unsigned NumBits) const;
  1365.  
  1366.   /// Return a dependent bit-precise integer type with the specified signedness
  1367.   /// and bit count.
  1368.   QualType getDependentBitIntType(bool Unsigned, Expr *BitsExpr) const;
  1369.  
  1370.   /// Gets the struct used to keep track of the extended descriptor for
  1371.   /// pointer to blocks.
  1372.   QualType getBlockDescriptorExtendedType() const;
  1373.  
  1374.   /// Map an AST Type to an OpenCLTypeKind enum value.
  1375.   OpenCLTypeKind getOpenCLTypeKind(const Type *T) const;
  1376.  
  1377.   /// Get address space for OpenCL type.
  1378.   LangAS getOpenCLTypeAddrSpace(const Type *T) const;
  1379.  
  1380.   /// Returns default address space based on OpenCL version and enabled features
  1381.   inline LangAS getDefaultOpenCLPointeeAddrSpace() {
  1382.     return LangOpts.OpenCLGenericAddressSpace ? LangAS::opencl_generic
  1383.                                               : LangAS::opencl_private;
  1384.   }
  1385.  
  1386.   void setcudaConfigureCallDecl(FunctionDecl *FD) {
  1387.     cudaConfigureCallDecl = FD;
  1388.   }
  1389.  
  1390.   FunctionDecl *getcudaConfigureCallDecl() {
  1391.     return cudaConfigureCallDecl;
  1392.   }
  1393.  
  1394.   /// Returns true iff we need copy/dispose helpers for the given type.
  1395.   bool BlockRequiresCopying(QualType Ty, const VarDecl *D);
  1396.  
  1397.   /// Returns true, if given type has a known lifetime. HasByrefExtendedLayout
  1398.   /// is set to false in this case. If HasByrefExtendedLayout returns true,
  1399.   /// byref variable has extended lifetime.
  1400.   bool getByrefLifetime(QualType Ty,
  1401.                         Qualifiers::ObjCLifetime &Lifetime,
  1402.                         bool &HasByrefExtendedLayout) const;
  1403.  
  1404.   /// Return the uniqued reference to the type for an lvalue reference
  1405.   /// to the specified type.
  1406.   QualType getLValueReferenceType(QualType T, bool SpelledAsLValue = true)
  1407.     const;
  1408.  
  1409.   /// Return the uniqued reference to the type for an rvalue reference
  1410.   /// to the specified type.
  1411.   QualType getRValueReferenceType(QualType T) const;
  1412.  
  1413.   /// Return the uniqued reference to the type for a member pointer to
  1414.   /// the specified type in the specified class.
  1415.   ///
  1416.   /// The class \p Cls is a \c Type because it could be a dependent name.
  1417.   QualType getMemberPointerType(QualType T, const Type *Cls) const;
  1418.  
  1419.   /// Return a non-unique reference to the type for a variable array of
  1420.   /// the specified element type.
  1421.   QualType getVariableArrayType(QualType EltTy, Expr *NumElts,
  1422.                                 ArrayType::ArraySizeModifier ASM,
  1423.                                 unsigned IndexTypeQuals,
  1424.                                 SourceRange Brackets) const;
  1425.  
  1426.   /// Return a non-unique reference to the type for a dependently-sized
  1427.   /// array of the specified element type.
  1428.   ///
  1429.   /// FIXME: We will need these to be uniqued, or at least comparable, at some
  1430.   /// point.
  1431.   QualType getDependentSizedArrayType(QualType EltTy, Expr *NumElts,
  1432.                                       ArrayType::ArraySizeModifier ASM,
  1433.                                       unsigned IndexTypeQuals,
  1434.                                       SourceRange Brackets) const;
  1435.  
  1436.   /// Return a unique reference to the type for an incomplete array of
  1437.   /// the specified element type.
  1438.   QualType getIncompleteArrayType(QualType EltTy,
  1439.                                   ArrayType::ArraySizeModifier ASM,
  1440.                                   unsigned IndexTypeQuals) const;
  1441.  
  1442.   /// Return the unique reference to the type for a constant array of
  1443.   /// the specified element type.
  1444.   QualType getConstantArrayType(QualType EltTy, const llvm::APInt &ArySize,
  1445.                                 const Expr *SizeExpr,
  1446.                                 ArrayType::ArraySizeModifier ASM,
  1447.                                 unsigned IndexTypeQuals) const;
  1448.  
  1449.   /// Return a type for a constant array for a string literal of the
  1450.   /// specified element type and length.
  1451.   QualType getStringLiteralArrayType(QualType EltTy, unsigned Length) const;
  1452.  
  1453.   /// Returns a vla type where known sizes are replaced with [*].
  1454.   QualType getVariableArrayDecayedType(QualType Ty) const;
  1455.  
  1456.   // Convenience struct to return information about a builtin vector type.
  1457.   struct BuiltinVectorTypeInfo {
  1458.     QualType ElementType;
  1459.     llvm::ElementCount EC;
  1460.     unsigned NumVectors;
  1461.     BuiltinVectorTypeInfo(QualType ElementType, llvm::ElementCount EC,
  1462.                           unsigned NumVectors)
  1463.         : ElementType(ElementType), EC(EC), NumVectors(NumVectors) {}
  1464.   };
  1465.  
  1466.   /// Returns the element type, element count and number of vectors
  1467.   /// (in case of tuple) for a builtin vector type.
  1468.   BuiltinVectorTypeInfo
  1469.   getBuiltinVectorTypeInfo(const BuiltinType *VecTy) const;
  1470.  
  1471.   /// Return the unique reference to a scalable vector type of the specified
  1472.   /// element type and scalable number of elements.
  1473.   ///
  1474.   /// \pre \p EltTy must be a built-in type.
  1475.   QualType getScalableVectorType(QualType EltTy, unsigned NumElts) const;
  1476.  
  1477.   /// Return the unique reference to a vector type of the specified
  1478.   /// element type and size.
  1479.   ///
  1480.   /// \pre \p VectorType must be a built-in type.
  1481.   QualType getVectorType(QualType VectorType, unsigned NumElts,
  1482.                          VectorType::VectorKind VecKind) const;
  1483.   /// Return the unique reference to the type for a dependently sized vector of
  1484.   /// the specified element type.
  1485.   QualType getDependentVectorType(QualType VectorType, Expr *SizeExpr,
  1486.                                   SourceLocation AttrLoc,
  1487.                                   VectorType::VectorKind VecKind) const;
  1488.  
  1489.   /// Return the unique reference to an extended vector type
  1490.   /// of the specified element type and size.
  1491.   ///
  1492.   /// \pre \p VectorType must be a built-in type.
  1493.   QualType getExtVectorType(QualType VectorType, unsigned NumElts) const;
  1494.  
  1495.   /// \pre Return a non-unique reference to the type for a dependently-sized
  1496.   /// vector of the specified element type.
  1497.   ///
  1498.   /// FIXME: We will need these to be uniqued, or at least comparable, at some
  1499.   /// point.
  1500.   QualType getDependentSizedExtVectorType(QualType VectorType,
  1501.                                           Expr *SizeExpr,
  1502.                                           SourceLocation AttrLoc) const;
  1503.  
  1504.   /// Return the unique reference to the matrix type of the specified element
  1505.   /// type and size
  1506.   ///
  1507.   /// \pre \p ElementType must be a valid matrix element type (see
  1508.   /// MatrixType::isValidElementType).
  1509.   QualType getConstantMatrixType(QualType ElementType, unsigned NumRows,
  1510.                                  unsigned NumColumns) const;
  1511.  
  1512.   /// Return the unique reference to the matrix type of the specified element
  1513.   /// type and size
  1514.   QualType getDependentSizedMatrixType(QualType ElementType, Expr *RowExpr,
  1515.                                        Expr *ColumnExpr,
  1516.                                        SourceLocation AttrLoc) const;
  1517.  
  1518.   QualType getDependentAddressSpaceType(QualType PointeeType,
  1519.                                         Expr *AddrSpaceExpr,
  1520.                                         SourceLocation AttrLoc) const;
  1521.  
  1522.   /// Return a K&R style C function type like 'int()'.
  1523.   QualType getFunctionNoProtoType(QualType ResultTy,
  1524.                                   const FunctionType::ExtInfo &Info) const;
  1525.  
  1526.   QualType getFunctionNoProtoType(QualType ResultTy) const {
  1527.     return getFunctionNoProtoType(ResultTy, FunctionType::ExtInfo());
  1528.   }
  1529.  
  1530.   /// Return a normal function type with a typed argument list.
  1531.   QualType getFunctionType(QualType ResultTy, ArrayRef<QualType> Args,
  1532.                            const FunctionProtoType::ExtProtoInfo &EPI) const {
  1533.     return getFunctionTypeInternal(ResultTy, Args, EPI, false);
  1534.   }
  1535.  
  1536.   QualType adjustStringLiteralBaseType(QualType StrLTy) const;
  1537.  
  1538. private:
  1539.   /// Return a normal function type with a typed argument list.
  1540.   QualType getFunctionTypeInternal(QualType ResultTy, ArrayRef<QualType> Args,
  1541.                                    const FunctionProtoType::ExtProtoInfo &EPI,
  1542.                                    bool OnlyWantCanonical) const;
  1543.   QualType
  1544.   getAutoTypeInternal(QualType DeducedType, AutoTypeKeyword Keyword,
  1545.                       bool IsDependent, bool IsPack = false,
  1546.                       ConceptDecl *TypeConstraintConcept = nullptr,
  1547.                       ArrayRef<TemplateArgument> TypeConstraintArgs = {},
  1548.                       bool IsCanon = false) const;
  1549.  
  1550. public:
  1551.   /// Return the unique reference to the type for the specified type
  1552.   /// declaration.
  1553.   QualType getTypeDeclType(const TypeDecl *Decl,
  1554.                            const TypeDecl *PrevDecl = nullptr) const {
  1555.     assert(Decl && "Passed null for Decl param");
  1556.     if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
  1557.  
  1558.     if (PrevDecl) {
  1559.       assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
  1560.       Decl->TypeForDecl = PrevDecl->TypeForDecl;
  1561.       return QualType(PrevDecl->TypeForDecl, 0);
  1562.     }
  1563.  
  1564.     return getTypeDeclTypeSlow(Decl);
  1565.   }
  1566.  
  1567.   QualType getUsingType(const UsingShadowDecl *Found,
  1568.                         QualType Underlying) const;
  1569.  
  1570.   /// Return the unique reference to the type for the specified
  1571.   /// typedef-name decl.
  1572.   QualType getTypedefType(const TypedefNameDecl *Decl,
  1573.                           QualType Underlying = QualType()) const;
  1574.  
  1575.   QualType getRecordType(const RecordDecl *Decl) const;
  1576.  
  1577.   QualType getEnumType(const EnumDecl *Decl) const;
  1578.  
  1579.   QualType
  1580.   getUnresolvedUsingType(const UnresolvedUsingTypenameDecl *Decl) const;
  1581.  
  1582.   QualType getInjectedClassNameType(CXXRecordDecl *Decl, QualType TST) const;
  1583.  
  1584.   QualType getAttributedType(attr::Kind attrKind, QualType modifiedType,
  1585.                              QualType equivalentType) const;
  1586.  
  1587.   QualType getBTFTagAttributedType(const BTFTypeTagAttr *BTFAttr,
  1588.                                    QualType Wrapped);
  1589.  
  1590.   QualType
  1591.   getSubstTemplateTypeParmType(QualType Replacement, Decl *AssociatedDecl,
  1592.                                unsigned Index,
  1593.                                std::optional<unsigned> PackIndex) const;
  1594.   QualType getSubstTemplateTypeParmPackType(Decl *AssociatedDecl,
  1595.                                             unsigned Index, bool Final,
  1596.                                             const TemplateArgument &ArgPack);
  1597.  
  1598.   QualType
  1599.   getTemplateTypeParmType(unsigned Depth, unsigned Index,
  1600.                           bool ParameterPack,
  1601.                           TemplateTypeParmDecl *ParmDecl = nullptr) const;
  1602.  
  1603.   QualType getTemplateSpecializationType(TemplateName T,
  1604.                                          ArrayRef<TemplateArgument> Args,
  1605.                                          QualType Canon = QualType()) const;
  1606.  
  1607.   QualType
  1608.   getCanonicalTemplateSpecializationType(TemplateName T,
  1609.                                          ArrayRef<TemplateArgument> Args) const;
  1610.  
  1611.   QualType getTemplateSpecializationType(TemplateName T,
  1612.                                          ArrayRef<TemplateArgumentLoc> Args,
  1613.                                          QualType Canon = QualType()) const;
  1614.  
  1615.   TypeSourceInfo *
  1616.   getTemplateSpecializationTypeInfo(TemplateName T, SourceLocation TLoc,
  1617.                                     const TemplateArgumentListInfo &Args,
  1618.                                     QualType Canon = QualType()) const;
  1619.  
  1620.   QualType getParenType(QualType NamedType) const;
  1621.  
  1622.   QualType getMacroQualifiedType(QualType UnderlyingTy,
  1623.                                  const IdentifierInfo *MacroII) const;
  1624.  
  1625.   QualType getElaboratedType(ElaboratedTypeKeyword Keyword,
  1626.                              NestedNameSpecifier *NNS, QualType NamedType,
  1627.                              TagDecl *OwnedTagDecl = nullptr) const;
  1628.   QualType getDependentNameType(ElaboratedTypeKeyword Keyword,
  1629.                                 NestedNameSpecifier *NNS,
  1630.                                 const IdentifierInfo *Name,
  1631.                                 QualType Canon = QualType()) const;
  1632.  
  1633.   QualType getDependentTemplateSpecializationType(
  1634.       ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
  1635.       const IdentifierInfo *Name, ArrayRef<TemplateArgumentLoc> Args) const;
  1636.   QualType getDependentTemplateSpecializationType(
  1637.       ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
  1638.       const IdentifierInfo *Name, ArrayRef<TemplateArgument> Args) const;
  1639.  
  1640.   TemplateArgument getInjectedTemplateArg(NamedDecl *ParamDecl);
  1641.  
  1642.   /// Get a template argument list with one argument per template parameter
  1643.   /// in a template parameter list, such as for the injected class name of
  1644.   /// a class template.
  1645.   void getInjectedTemplateArgs(const TemplateParameterList *Params,
  1646.                                SmallVectorImpl<TemplateArgument> &Args);
  1647.  
  1648.   /// Form a pack expansion type with the given pattern.
  1649.   /// \param NumExpansions The number of expansions for the pack, if known.
  1650.   /// \param ExpectPackInType If \c false, we should not expect \p Pattern to
  1651.   ///        contain an unexpanded pack. This only makes sense if the pack
  1652.   ///        expansion is used in a context where the arity is inferred from
  1653.   ///        elsewhere, such as if the pattern contains a placeholder type or
  1654.   ///        if this is the canonical type of another pack expansion type.
  1655.   QualType getPackExpansionType(QualType Pattern,
  1656.                                 std::optional<unsigned> NumExpansions,
  1657.                                 bool ExpectPackInType = true);
  1658.  
  1659.   QualType getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
  1660.                                 ObjCInterfaceDecl *PrevDecl = nullptr) const;
  1661.  
  1662.   /// Legacy interface: cannot provide type arguments or __kindof.
  1663.   QualType getObjCObjectType(QualType Base,
  1664.                              ObjCProtocolDecl * const *Protocols,
  1665.                              unsigned NumProtocols) const;
  1666.  
  1667.   QualType getObjCObjectType(QualType Base,
  1668.                              ArrayRef<QualType> typeArgs,
  1669.                              ArrayRef<ObjCProtocolDecl *> protocols,
  1670.                              bool isKindOf) const;
  1671.  
  1672.   QualType getObjCTypeParamType(const ObjCTypeParamDecl *Decl,
  1673.                                 ArrayRef<ObjCProtocolDecl *> protocols) const;
  1674.   void adjustObjCTypeParamBoundType(const ObjCTypeParamDecl *Orig,
  1675.                                     ObjCTypeParamDecl *New) const;
  1676.  
  1677.   bool ObjCObjectAdoptsQTypeProtocols(QualType QT, ObjCInterfaceDecl *Decl);
  1678.  
  1679.   /// QIdProtocolsAdoptObjCObjectProtocols - Checks that protocols in
  1680.   /// QT's qualified-id protocol list adopt all protocols in IDecl's list
  1681.   /// of protocols.
  1682.   bool QIdProtocolsAdoptObjCObjectProtocols(QualType QT,
  1683.                                             ObjCInterfaceDecl *IDecl);
  1684.  
  1685.   /// Return a ObjCObjectPointerType type for the given ObjCObjectType.
  1686.   QualType getObjCObjectPointerType(QualType OIT) const;
  1687.  
  1688.   /// C2x feature and GCC extension.
  1689.   QualType getTypeOfExprType(Expr *E, TypeOfKind Kind) const;
  1690.   QualType getTypeOfType(QualType QT, TypeOfKind Kind) const;
  1691.  
  1692.   QualType getReferenceQualifiedType(const Expr *e) const;
  1693.  
  1694.   /// C++11 decltype.
  1695.   QualType getDecltypeType(Expr *e, QualType UnderlyingType) const;
  1696.  
  1697.   /// Unary type transforms
  1698.   QualType getUnaryTransformType(QualType BaseType, QualType UnderlyingType,
  1699.                                  UnaryTransformType::UTTKind UKind) const;
  1700.  
  1701.   /// C++11 deduced auto type.
  1702.   QualType getAutoType(QualType DeducedType, AutoTypeKeyword Keyword,
  1703.                        bool IsDependent, bool IsPack = false,
  1704.                        ConceptDecl *TypeConstraintConcept = nullptr,
  1705.                        ArrayRef<TemplateArgument> TypeConstraintArgs ={}) const;
  1706.  
  1707.   /// C++11 deduction pattern for 'auto' type.
  1708.   QualType getAutoDeductType() const;
  1709.  
  1710.   /// C++11 deduction pattern for 'auto &&' type.
  1711.   QualType getAutoRRefDeductType() const;
  1712.  
  1713.   /// C++17 deduced class template specialization type.
  1714.   QualType getDeducedTemplateSpecializationType(TemplateName Template,
  1715.                                                 QualType DeducedType,
  1716.                                                 bool IsDependent) const;
  1717.  
  1718.   /// Return the unique reference to the type for the specified TagDecl
  1719.   /// (struct/union/class/enum) decl.
  1720.   QualType getTagDeclType(const TagDecl *Decl) const;
  1721.  
  1722.   /// Return the unique type for "size_t" (C99 7.17), defined in
  1723.   /// <stddef.h>.
  1724.   ///
  1725.   /// The sizeof operator requires this (C99 6.5.3.4p4).
  1726.   CanQualType getSizeType() const;
  1727.  
  1728.   /// Return the unique signed counterpart of
  1729.   /// the integer type corresponding to size_t.
  1730.   CanQualType getSignedSizeType() const;
  1731.  
  1732.   /// Return the unique type for "intmax_t" (C99 7.18.1.5), defined in
  1733.   /// <stdint.h>.
  1734.   CanQualType getIntMaxType() const;
  1735.  
  1736.   /// Return the unique type for "uintmax_t" (C99 7.18.1.5), defined in
  1737.   /// <stdint.h>.
  1738.   CanQualType getUIntMaxType() const;
  1739.  
  1740.   /// Return the unique wchar_t type available in C++ (and available as
  1741.   /// __wchar_t as a Microsoft extension).
  1742.   QualType getWCharType() const { return WCharTy; }
  1743.  
  1744.   /// Return the type of wide characters. In C++, this returns the
  1745.   /// unique wchar_t type. In C99, this returns a type compatible with the type
  1746.   /// defined in <stddef.h> as defined by the target.
  1747.   QualType getWideCharType() const { return WideCharTy; }
  1748.  
  1749.   /// Return the type of "signed wchar_t".
  1750.   ///
  1751.   /// Used when in C++, as a GCC extension.
  1752.   QualType getSignedWCharType() const;
  1753.  
  1754.   /// Return the type of "unsigned wchar_t".
  1755.   ///
  1756.   /// Used when in C++, as a GCC extension.
  1757.   QualType getUnsignedWCharType() const;
  1758.  
  1759.   /// In C99, this returns a type compatible with the type
  1760.   /// defined in <stddef.h> as defined by the target.
  1761.   QualType getWIntType() const { return WIntTy; }
  1762.  
  1763.   /// Return a type compatible with "intptr_t" (C99 7.18.1.4),
  1764.   /// as defined by the target.
  1765.   QualType getIntPtrType() const;
  1766.  
  1767.   /// Return a type compatible with "uintptr_t" (C99 7.18.1.4),
  1768.   /// as defined by the target.
  1769.   QualType getUIntPtrType() const;
  1770.  
  1771.   /// Return the unique type for "ptrdiff_t" (C99 7.17) defined in
  1772.   /// <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
  1773.   QualType getPointerDiffType() const;
  1774.  
  1775.   /// Return the unique unsigned counterpart of "ptrdiff_t"
  1776.   /// integer type. The standard (C11 7.21.6.1p7) refers to this type
  1777.   /// in the definition of %tu format specifier.
  1778.   QualType getUnsignedPointerDiffType() const;
  1779.  
  1780.   /// Return the unique type for "pid_t" defined in
  1781.   /// <sys/types.h>. We need this to compute the correct type for vfork().
  1782.   QualType getProcessIDType() const;
  1783.  
  1784.   /// Return the C structure type used to represent constant CFStrings.
  1785.   QualType getCFConstantStringType() const;
  1786.  
  1787.   /// Returns the C struct type for objc_super
  1788.   QualType getObjCSuperType() const;
  1789.   void setObjCSuperType(QualType ST) { ObjCSuperType = ST; }
  1790.  
  1791.   /// Get the structure type used to representation CFStrings, or NULL
  1792.   /// if it hasn't yet been built.
  1793.   QualType getRawCFConstantStringType() const {
  1794.     if (CFConstantStringTypeDecl)
  1795.       return getTypedefType(CFConstantStringTypeDecl);
  1796.     return QualType();
  1797.   }
  1798.   void setCFConstantStringType(QualType T);
  1799.   TypedefDecl *getCFConstantStringDecl() const;
  1800.   RecordDecl *getCFConstantStringTagDecl() const;
  1801.  
  1802.   // This setter/getter represents the ObjC type for an NSConstantString.
  1803.   void setObjCConstantStringInterface(ObjCInterfaceDecl *Decl);
  1804.   QualType getObjCConstantStringInterface() const {
  1805.     return ObjCConstantStringType;
  1806.   }
  1807.  
  1808.   QualType getObjCNSStringType() const {
  1809.     return ObjCNSStringType;
  1810.   }
  1811.  
  1812.   void setObjCNSStringType(QualType T) {
  1813.     ObjCNSStringType = T;
  1814.   }
  1815.  
  1816.   /// Retrieve the type that \c id has been defined to, which may be
  1817.   /// different from the built-in \c id if \c id has been typedef'd.
  1818.   QualType getObjCIdRedefinitionType() const {
  1819.     if (ObjCIdRedefinitionType.isNull())
  1820.       return getObjCIdType();
  1821.     return ObjCIdRedefinitionType;
  1822.   }
  1823.  
  1824.   /// Set the user-written type that redefines \c id.
  1825.   void setObjCIdRedefinitionType(QualType RedefType) {
  1826.     ObjCIdRedefinitionType = RedefType;
  1827.   }
  1828.  
  1829.   /// Retrieve the type that \c Class has been defined to, which may be
  1830.   /// different from the built-in \c Class if \c Class has been typedef'd.
  1831.   QualType getObjCClassRedefinitionType() const {
  1832.     if (ObjCClassRedefinitionType.isNull())
  1833.       return getObjCClassType();
  1834.     return ObjCClassRedefinitionType;
  1835.   }
  1836.  
  1837.   /// Set the user-written type that redefines 'SEL'.
  1838.   void setObjCClassRedefinitionType(QualType RedefType) {
  1839.     ObjCClassRedefinitionType = RedefType;
  1840.   }
  1841.  
  1842.   /// Retrieve the type that 'SEL' has been defined to, which may be
  1843.   /// different from the built-in 'SEL' if 'SEL' has been typedef'd.
  1844.   QualType getObjCSelRedefinitionType() const {
  1845.     if (ObjCSelRedefinitionType.isNull())
  1846.       return getObjCSelType();
  1847.     return ObjCSelRedefinitionType;
  1848.   }
  1849.  
  1850.   /// Set the user-written type that redefines 'SEL'.
  1851.   void setObjCSelRedefinitionType(QualType RedefType) {
  1852.     ObjCSelRedefinitionType = RedefType;
  1853.   }
  1854.  
  1855.   /// Retrieve the identifier 'NSObject'.
  1856.   IdentifierInfo *getNSObjectName() const {
  1857.     if (!NSObjectName) {
  1858.       NSObjectName = &Idents.get("NSObject");
  1859.     }
  1860.  
  1861.     return NSObjectName;
  1862.   }
  1863.  
  1864.   /// Retrieve the identifier 'NSCopying'.
  1865.   IdentifierInfo *getNSCopyingName() {
  1866.     if (!NSCopyingName) {
  1867.       NSCopyingName = &Idents.get("NSCopying");
  1868.     }
  1869.  
  1870.     return NSCopyingName;
  1871.   }
  1872.  
  1873.   CanQualType getNSUIntegerType() const;
  1874.  
  1875.   CanQualType getNSIntegerType() const;
  1876.  
  1877.   /// Retrieve the identifier 'bool'.
  1878.   IdentifierInfo *getBoolName() const {
  1879.     if (!BoolName)
  1880.       BoolName = &Idents.get("bool");
  1881.     return BoolName;
  1882.   }
  1883.  
  1884.   IdentifierInfo *getMakeIntegerSeqName() const {
  1885.     if (!MakeIntegerSeqName)
  1886.       MakeIntegerSeqName = &Idents.get("__make_integer_seq");
  1887.     return MakeIntegerSeqName;
  1888.   }
  1889.  
  1890.   IdentifierInfo *getTypePackElementName() const {
  1891.     if (!TypePackElementName)
  1892.       TypePackElementName = &Idents.get("__type_pack_element");
  1893.     return TypePackElementName;
  1894.   }
  1895.  
  1896.   /// Retrieve the Objective-C "instancetype" type, if already known;
  1897.   /// otherwise, returns a NULL type;
  1898.   QualType getObjCInstanceType() {
  1899.     return getTypeDeclType(getObjCInstanceTypeDecl());
  1900.   }
  1901.  
  1902.   /// Retrieve the typedef declaration corresponding to the Objective-C
  1903.   /// "instancetype" type.
  1904.   TypedefDecl *getObjCInstanceTypeDecl();
  1905.  
  1906.   /// Set the type for the C FILE type.
  1907.   void setFILEDecl(TypeDecl *FILEDecl) { this->FILEDecl = FILEDecl; }
  1908.  
  1909.   /// Retrieve the C FILE type.
  1910.   QualType getFILEType() const {
  1911.     if (FILEDecl)
  1912.       return getTypeDeclType(FILEDecl);
  1913.     return QualType();
  1914.   }
  1915.  
  1916.   /// Set the type for the C jmp_buf type.
  1917.   void setjmp_bufDecl(TypeDecl *jmp_bufDecl) {
  1918.     this->jmp_bufDecl = jmp_bufDecl;
  1919.   }
  1920.  
  1921.   /// Retrieve the C jmp_buf type.
  1922.   QualType getjmp_bufType() const {
  1923.     if (jmp_bufDecl)
  1924.       return getTypeDeclType(jmp_bufDecl);
  1925.     return QualType();
  1926.   }
  1927.  
  1928.   /// Set the type for the C sigjmp_buf type.
  1929.   void setsigjmp_bufDecl(TypeDecl *sigjmp_bufDecl) {
  1930.     this->sigjmp_bufDecl = sigjmp_bufDecl;
  1931.   }
  1932.  
  1933.   /// Retrieve the C sigjmp_buf type.
  1934.   QualType getsigjmp_bufType() const {
  1935.     if (sigjmp_bufDecl)
  1936.       return getTypeDeclType(sigjmp_bufDecl);
  1937.     return QualType();
  1938.   }
  1939.  
  1940.   /// Set the type for the C ucontext_t type.
  1941.   void setucontext_tDecl(TypeDecl *ucontext_tDecl) {
  1942.     this->ucontext_tDecl = ucontext_tDecl;
  1943.   }
  1944.  
  1945.   /// Retrieve the C ucontext_t type.
  1946.   QualType getucontext_tType() const {
  1947.     if (ucontext_tDecl)
  1948.       return getTypeDeclType(ucontext_tDecl);
  1949.     return QualType();
  1950.   }
  1951.  
  1952.   /// The result type of logical operations, '<', '>', '!=', etc.
  1953.   QualType getLogicalOperationType() const {
  1954.     return getLangOpts().CPlusPlus ? BoolTy : IntTy;
  1955.   }
  1956.  
  1957.   /// Emit the Objective-CC type encoding for the given type \p T into
  1958.   /// \p S.
  1959.   ///
  1960.   /// If \p Field is specified then record field names are also encoded.
  1961.   void getObjCEncodingForType(QualType T, std::string &S,
  1962.                               const FieldDecl *Field=nullptr,
  1963.                               QualType *NotEncodedT=nullptr) const;
  1964.  
  1965.   /// Emit the Objective-C property type encoding for the given
  1966.   /// type \p T into \p S.
  1967.   void getObjCEncodingForPropertyType(QualType T, std::string &S) const;
  1968.  
  1969.   void getLegacyIntegralTypeEncoding(QualType &t) const;
  1970.  
  1971.   /// Put the string version of the type qualifiers \p QT into \p S.
  1972.   void getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
  1973.                                        std::string &S) const;
  1974.  
  1975.   /// Emit the encoded type for the function \p Decl into \p S.
  1976.   ///
  1977.   /// This is in the same format as Objective-C method encodings.
  1978.   ///
  1979.   /// \returns true if an error occurred (e.g., because one of the parameter
  1980.   /// types is incomplete), false otherwise.
  1981.   std::string getObjCEncodingForFunctionDecl(const FunctionDecl *Decl) const;
  1982.  
  1983.   /// Emit the encoded type for the method declaration \p Decl into
  1984.   /// \p S.
  1985.   std::string getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
  1986.                                            bool Extended = false) const;
  1987.  
  1988.   /// Return the encoded type for this block declaration.
  1989.   std::string getObjCEncodingForBlock(const BlockExpr *blockExpr) const;
  1990.  
  1991.   /// getObjCEncodingForPropertyDecl - Return the encoded type for
  1992.   /// this method declaration. If non-NULL, Container must be either
  1993.   /// an ObjCCategoryImplDecl or ObjCImplementationDecl; it should
  1994.   /// only be NULL when getting encodings for protocol properties.
  1995.   std::string getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
  1996.                                              const Decl *Container) const;
  1997.  
  1998.   bool ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
  1999.                                       ObjCProtocolDecl *rProto) const;
  2000.  
  2001.   ObjCPropertyImplDecl *getObjCPropertyImplDeclForPropertyDecl(
  2002.                                                   const ObjCPropertyDecl *PD,
  2003.                                                   const Decl *Container) const;
  2004.  
  2005.   /// Return the size of type \p T for Objective-C encoding purpose,
  2006.   /// in characters.
  2007.   CharUnits getObjCEncodingTypeSize(QualType T) const;
  2008.  
  2009.   /// Retrieve the typedef corresponding to the predefined \c id type
  2010.   /// in Objective-C.
  2011.   TypedefDecl *getObjCIdDecl() const;
  2012.  
  2013.   /// Represents the Objective-CC \c id type.
  2014.   ///
  2015.   /// This is set up lazily, by Sema.  \c id is always a (typedef for a)
  2016.   /// pointer type, a pointer to a struct.
  2017.   QualType getObjCIdType() const {
  2018.     return getTypeDeclType(getObjCIdDecl());
  2019.   }
  2020.  
  2021.   /// Retrieve the typedef corresponding to the predefined 'SEL' type
  2022.   /// in Objective-C.
  2023.   TypedefDecl *getObjCSelDecl() const;
  2024.  
  2025.   /// Retrieve the type that corresponds to the predefined Objective-C
  2026.   /// 'SEL' type.
  2027.   QualType getObjCSelType() const {
  2028.     return getTypeDeclType(getObjCSelDecl());
  2029.   }
  2030.  
  2031.   /// Retrieve the typedef declaration corresponding to the predefined
  2032.   /// Objective-C 'Class' type.
  2033.   TypedefDecl *getObjCClassDecl() const;
  2034.  
  2035.   /// Represents the Objective-C \c Class type.
  2036.   ///
  2037.   /// This is set up lazily, by Sema.  \c Class is always a (typedef for a)
  2038.   /// pointer type, a pointer to a struct.
  2039.   QualType getObjCClassType() const {
  2040.     return getTypeDeclType(getObjCClassDecl());
  2041.   }
  2042.  
  2043.   /// Retrieve the Objective-C class declaration corresponding to
  2044.   /// the predefined \c Protocol class.
  2045.   ObjCInterfaceDecl *getObjCProtocolDecl() const;
  2046.  
  2047.   /// Retrieve declaration of 'BOOL' typedef
  2048.   TypedefDecl *getBOOLDecl() const {
  2049.     return BOOLDecl;
  2050.   }
  2051.  
  2052.   /// Save declaration of 'BOOL' typedef
  2053.   void setBOOLDecl(TypedefDecl *TD) {
  2054.     BOOLDecl = TD;
  2055.   }
  2056.  
  2057.   /// type of 'BOOL' type.
  2058.   QualType getBOOLType() const {
  2059.     return getTypeDeclType(getBOOLDecl());
  2060.   }
  2061.  
  2062.   /// Retrieve the type of the Objective-C \c Protocol class.
  2063.   QualType getObjCProtoType() const {
  2064.     return getObjCInterfaceType(getObjCProtocolDecl());
  2065.   }
  2066.  
  2067.   /// Retrieve the C type declaration corresponding to the predefined
  2068.   /// \c __builtin_va_list type.
  2069.   TypedefDecl *getBuiltinVaListDecl() const;
  2070.  
  2071.   /// Retrieve the type of the \c __builtin_va_list type.
  2072.   QualType getBuiltinVaListType() const {
  2073.     return getTypeDeclType(getBuiltinVaListDecl());
  2074.   }
  2075.  
  2076.   /// Retrieve the C type declaration corresponding to the predefined
  2077.   /// \c __va_list_tag type used to help define the \c __builtin_va_list type
  2078.   /// for some targets.
  2079.   Decl *getVaListTagDecl() const;
  2080.  
  2081.   /// Retrieve the C type declaration corresponding to the predefined
  2082.   /// \c __builtin_ms_va_list type.
  2083.   TypedefDecl *getBuiltinMSVaListDecl() const;
  2084.  
  2085.   /// Retrieve the type of the \c __builtin_ms_va_list type.
  2086.   QualType getBuiltinMSVaListType() const {
  2087.     return getTypeDeclType(getBuiltinMSVaListDecl());
  2088.   }
  2089.  
  2090.   /// Retrieve the implicitly-predeclared 'struct _GUID' declaration.
  2091.   TagDecl *getMSGuidTagDecl() const { return MSGuidTagDecl; }
  2092.  
  2093.   /// Retrieve the implicitly-predeclared 'struct _GUID' type.
  2094.   QualType getMSGuidType() const {
  2095.     assert(MSGuidTagDecl && "asked for GUID type but MS extensions disabled");
  2096.     return getTagDeclType(MSGuidTagDecl);
  2097.   }
  2098.  
  2099.   /// Return whether a declaration to a builtin is allowed to be
  2100.   /// overloaded/redeclared.
  2101.   bool canBuiltinBeRedeclared(const FunctionDecl *) const;
  2102.  
  2103.   /// Return a type with additional \c const, \c volatile, or
  2104.   /// \c restrict qualifiers.
  2105.   QualType getCVRQualifiedType(QualType T, unsigned CVR) const {
  2106.     return getQualifiedType(T, Qualifiers::fromCVRMask(CVR));
  2107.   }
  2108.  
  2109.   /// Un-split a SplitQualType.
  2110.   QualType getQualifiedType(SplitQualType split) const {
  2111.     return getQualifiedType(split.Ty, split.Quals);
  2112.   }
  2113.  
  2114.   /// Return a type with additional qualifiers.
  2115.   QualType getQualifiedType(QualType T, Qualifiers Qs) const {
  2116.     if (!Qs.hasNonFastQualifiers())
  2117.       return T.withFastQualifiers(Qs.getFastQualifiers());
  2118.     QualifierCollector Qc(Qs);
  2119.     const Type *Ptr = Qc.strip(T);
  2120.     return getExtQualType(Ptr, Qc);
  2121.   }
  2122.  
  2123.   /// Return a type with additional qualifiers.
  2124.   QualType getQualifiedType(const Type *T, Qualifiers Qs) const {
  2125.     if (!Qs.hasNonFastQualifiers())
  2126.       return QualType(T, Qs.getFastQualifiers());
  2127.     return getExtQualType(T, Qs);
  2128.   }
  2129.  
  2130.   /// Return a type with the given lifetime qualifier.
  2131.   ///
  2132.   /// \pre Neither type.ObjCLifetime() nor \p lifetime may be \c OCL_None.
  2133.   QualType getLifetimeQualifiedType(QualType type,
  2134.                                     Qualifiers::ObjCLifetime lifetime) {
  2135.     assert(type.getObjCLifetime() == Qualifiers::OCL_None);
  2136.     assert(lifetime != Qualifiers::OCL_None);
  2137.  
  2138.     Qualifiers qs;
  2139.     qs.addObjCLifetime(lifetime);
  2140.     return getQualifiedType(type, qs);
  2141.   }
  2142.  
  2143.   /// getUnqualifiedObjCPointerType - Returns version of
  2144.   /// Objective-C pointer type with lifetime qualifier removed.
  2145.   QualType getUnqualifiedObjCPointerType(QualType type) const {
  2146.     if (!type.getTypePtr()->isObjCObjectPointerType() ||
  2147.         !type.getQualifiers().hasObjCLifetime())
  2148.       return type;
  2149.     Qualifiers Qs = type.getQualifiers();
  2150.     Qs.removeObjCLifetime();
  2151.     return getQualifiedType(type.getUnqualifiedType(), Qs);
  2152.   }
  2153.  
  2154.   unsigned char getFixedPointScale(QualType Ty) const;
  2155.   unsigned char getFixedPointIBits(QualType Ty) const;
  2156.   llvm::FixedPointSemantics getFixedPointSemantics(QualType Ty) const;
  2157.   llvm::APFixedPoint getFixedPointMax(QualType Ty) const;
  2158.   llvm::APFixedPoint getFixedPointMin(QualType Ty) const;
  2159.  
  2160.   DeclarationNameInfo getNameForTemplate(TemplateName Name,
  2161.                                          SourceLocation NameLoc) const;
  2162.  
  2163.   TemplateName getOverloadedTemplateName(UnresolvedSetIterator Begin,
  2164.                                          UnresolvedSetIterator End) const;
  2165.   TemplateName getAssumedTemplateName(DeclarationName Name) const;
  2166.  
  2167.   TemplateName getQualifiedTemplateName(NestedNameSpecifier *NNS,
  2168.                                         bool TemplateKeyword,
  2169.                                         TemplateName Template) const;
  2170.  
  2171.   TemplateName getDependentTemplateName(NestedNameSpecifier *NNS,
  2172.                                         const IdentifierInfo *Name) const;
  2173.   TemplateName getDependentTemplateName(NestedNameSpecifier *NNS,
  2174.                                         OverloadedOperatorKind Operator) const;
  2175.   TemplateName
  2176.   getSubstTemplateTemplateParm(TemplateName replacement, Decl *AssociatedDecl,
  2177.                                unsigned Index,
  2178.                                std::optional<unsigned> PackIndex) const;
  2179.   TemplateName getSubstTemplateTemplateParmPack(const TemplateArgument &ArgPack,
  2180.                                                 Decl *AssociatedDecl,
  2181.                                                 unsigned Index,
  2182.                                                 bool Final) const;
  2183.  
  2184.   enum GetBuiltinTypeError {
  2185.     /// No error
  2186.     GE_None,
  2187.  
  2188.     /// Missing a type
  2189.     GE_Missing_type,
  2190.  
  2191.     /// Missing a type from <stdio.h>
  2192.     GE_Missing_stdio,
  2193.  
  2194.     /// Missing a type from <setjmp.h>
  2195.     GE_Missing_setjmp,
  2196.  
  2197.     /// Missing a type from <ucontext.h>
  2198.     GE_Missing_ucontext
  2199.   };
  2200.  
  2201.   QualType DecodeTypeStr(const char *&Str, const ASTContext &Context,
  2202.                          ASTContext::GetBuiltinTypeError &Error,
  2203.                          bool &RequireICE, bool AllowTypeModifiers) const;
  2204.  
  2205.   /// Return the type for the specified builtin.
  2206.   ///
  2207.   /// If \p IntegerConstantArgs is non-null, it is filled in with a bitmask of
  2208.   /// arguments to the builtin that are required to be integer constant
  2209.   /// expressions.
  2210.   QualType GetBuiltinType(unsigned ID, GetBuiltinTypeError &Error,
  2211.                           unsigned *IntegerConstantArgs = nullptr) const;
  2212.  
  2213.   /// Types and expressions required to build C++2a three-way comparisons
  2214.   /// using operator<=>, including the values return by builtin <=> operators.
  2215.   ComparisonCategories CompCategories;
  2216.  
  2217. private:
  2218.   CanQualType getFromTargetType(unsigned Type) const;
  2219.   TypeInfo getTypeInfoImpl(const Type *T) const;
  2220.  
  2221.   //===--------------------------------------------------------------------===//
  2222.   //                         Type Predicates.
  2223.   //===--------------------------------------------------------------------===//
  2224.  
  2225. public:
  2226.   /// Return one of the GCNone, Weak or Strong Objective-C garbage
  2227.   /// collection attributes.
  2228.   Qualifiers::GC getObjCGCAttrKind(QualType Ty) const;
  2229.  
  2230.   /// Return true if the given vector types are of the same unqualified
  2231.   /// type or if they are equivalent to the same GCC vector type.
  2232.   ///
  2233.   /// \note This ignores whether they are target-specific (AltiVec or Neon)
  2234.   /// types.
  2235.   bool areCompatibleVectorTypes(QualType FirstVec, QualType SecondVec);
  2236.  
  2237.   /// Return true if the given types are an SVE builtin and a VectorType that
  2238.   /// is a fixed-length representation of the SVE builtin for a specific
  2239.   /// vector-length.
  2240.   bool areCompatibleSveTypes(QualType FirstType, QualType SecondType);
  2241.  
  2242.   /// Return true if the given vector types are lax-compatible SVE vector types,
  2243.   /// false otherwise.
  2244.   bool areLaxCompatibleSveTypes(QualType FirstType, QualType SecondType);
  2245.  
  2246.   /// Return true if the type has been explicitly qualified with ObjC ownership.
  2247.   /// A type may be implicitly qualified with ownership under ObjC ARC, and in
  2248.   /// some cases the compiler treats these differently.
  2249.   bool hasDirectOwnershipQualifier(QualType Ty) const;
  2250.  
  2251.   /// Return true if this is an \c NSObject object with its \c NSObject
  2252.   /// attribute set.
  2253.   static bool isObjCNSObjectType(QualType Ty) {
  2254.     return Ty->isObjCNSObjectType();
  2255.   }
  2256.  
  2257.   //===--------------------------------------------------------------------===//
  2258.   //                         Type Sizing and Analysis
  2259.   //===--------------------------------------------------------------------===//
  2260.  
  2261.   /// Return the APFloat 'semantics' for the specified scalar floating
  2262.   /// point type.
  2263.   const llvm::fltSemantics &getFloatTypeSemantics(QualType T) const;
  2264.  
  2265.   /// Get the size and alignment of the specified complete type in bits.
  2266.   TypeInfo getTypeInfo(const Type *T) const;
  2267.   TypeInfo getTypeInfo(QualType T) const { return getTypeInfo(T.getTypePtr()); }
  2268.  
  2269.   /// Get default simd alignment of the specified complete type in bits.
  2270.   unsigned getOpenMPDefaultSimdAlign(QualType T) const;
  2271.  
  2272.   /// Return the size of the specified (complete) type \p T, in bits.
  2273.   uint64_t getTypeSize(QualType T) const { return getTypeInfo(T).Width; }
  2274.   uint64_t getTypeSize(const Type *T) const { return getTypeInfo(T).Width; }
  2275.  
  2276.   /// Return the size of the character type, in bits.
  2277.   uint64_t getCharWidth() const {
  2278.     return getTypeSize(CharTy);
  2279.   }
  2280.  
  2281.   /// Convert a size in bits to a size in characters.
  2282.   CharUnits toCharUnitsFromBits(int64_t BitSize) const;
  2283.  
  2284.   /// Convert a size in characters to a size in bits.
  2285.   int64_t toBits(CharUnits CharSize) const;
  2286.  
  2287.   /// Return the size of the specified (complete) type \p T, in
  2288.   /// characters.
  2289.   CharUnits getTypeSizeInChars(QualType T) const;
  2290.   CharUnits getTypeSizeInChars(const Type *T) const;
  2291.  
  2292.   std::optional<CharUnits> getTypeSizeInCharsIfKnown(QualType Ty) const {
  2293.     if (Ty->isIncompleteType() || Ty->isDependentType())
  2294.       return std::nullopt;
  2295.     return getTypeSizeInChars(Ty);
  2296.   }
  2297.  
  2298.   std::optional<CharUnits> getTypeSizeInCharsIfKnown(const Type *Ty) const {
  2299.     return getTypeSizeInCharsIfKnown(QualType(Ty, 0));
  2300.   }
  2301.  
  2302.   /// Return the ABI-specified alignment of a (complete) type \p T, in
  2303.   /// bits.
  2304.   unsigned getTypeAlign(QualType T) const { return getTypeInfo(T).Align; }
  2305.   unsigned getTypeAlign(const Type *T) const { return getTypeInfo(T).Align; }
  2306.  
  2307.   /// Return the ABI-specified natural alignment of a (complete) type \p T,
  2308.   /// before alignment adjustments, in bits.
  2309.   ///
  2310.   /// This alignment is curently used only by ARM and AArch64 when passing
  2311.   /// arguments of a composite type.
  2312.   unsigned getTypeUnadjustedAlign(QualType T) const {
  2313.     return getTypeUnadjustedAlign(T.getTypePtr());
  2314.   }
  2315.   unsigned getTypeUnadjustedAlign(const Type *T) const;
  2316.  
  2317.   /// Return the alignment of a type, in bits, or 0 if
  2318.   /// the type is incomplete and we cannot determine the alignment (for
  2319.   /// example, from alignment attributes). The returned alignment is the
  2320.   /// Preferred alignment if NeedsPreferredAlignment is true, otherwise is the
  2321.   /// ABI alignment.
  2322.   unsigned getTypeAlignIfKnown(QualType T,
  2323.                                bool NeedsPreferredAlignment = false) const;
  2324.  
  2325.   /// Return the ABI-specified alignment of a (complete) type \p T, in
  2326.   /// characters.
  2327.   CharUnits getTypeAlignInChars(QualType T) const;
  2328.   CharUnits getTypeAlignInChars(const Type *T) const;
  2329.  
  2330.   /// Return the PreferredAlignment of a (complete) type \p T, in
  2331.   /// characters.
  2332.   CharUnits getPreferredTypeAlignInChars(QualType T) const {
  2333.     return toCharUnitsFromBits(getPreferredTypeAlign(T));
  2334.   }
  2335.  
  2336.   /// getTypeUnadjustedAlignInChars - Return the ABI-specified alignment of a type,
  2337.   /// in characters, before alignment adjustments. This method does not work on
  2338.   /// incomplete types.
  2339.   CharUnits getTypeUnadjustedAlignInChars(QualType T) const;
  2340.   CharUnits getTypeUnadjustedAlignInChars(const Type *T) const;
  2341.  
  2342.   // getTypeInfoDataSizeInChars - Return the size of a type, in chars. If the
  2343.   // type is a record, its data size is returned.
  2344.   TypeInfoChars getTypeInfoDataSizeInChars(QualType T) const;
  2345.  
  2346.   TypeInfoChars getTypeInfoInChars(const Type *T) const;
  2347.   TypeInfoChars getTypeInfoInChars(QualType T) const;
  2348.  
  2349.   /// Determine if the alignment the type has was required using an
  2350.   /// alignment attribute.
  2351.   bool isAlignmentRequired(const Type *T) const;
  2352.   bool isAlignmentRequired(QualType T) const;
  2353.  
  2354.   /// More type predicates useful for type checking/promotion
  2355.   bool isPromotableIntegerType(QualType T) const; // C99 6.3.1.1p2
  2356.  
  2357.   /// Return the "preferred" alignment of the specified type \p T for
  2358.   /// the current target, in bits.
  2359.   ///
  2360.   /// This can be different than the ABI alignment in cases where it is
  2361.   /// beneficial for performance or backwards compatibility preserving to
  2362.   /// overalign a data type. (Note: despite the name, the preferred alignment
  2363.   /// is ABI-impacting, and not an optimization.)
  2364.   unsigned getPreferredTypeAlign(QualType T) const {
  2365.     return getPreferredTypeAlign(T.getTypePtr());
  2366.   }
  2367.   unsigned getPreferredTypeAlign(const Type *T) const;
  2368.  
  2369.   /// Return the default alignment for __attribute__((aligned)) on
  2370.   /// this target, to be used if no alignment value is specified.
  2371.   unsigned getTargetDefaultAlignForAttributeAligned() const;
  2372.  
  2373.   /// Return the alignment in bits that should be given to a
  2374.   /// global variable with type \p T.
  2375.   unsigned getAlignOfGlobalVar(QualType T) const;
  2376.  
  2377.   /// Return the alignment in characters that should be given to a
  2378.   /// global variable with type \p T.
  2379.   CharUnits getAlignOfGlobalVarInChars(QualType T) const;
  2380.  
  2381.   /// Return a conservative estimate of the alignment of the specified
  2382.   /// decl \p D.
  2383.   ///
  2384.   /// \pre \p D must not be a bitfield type, as bitfields do not have a valid
  2385.   /// alignment.
  2386.   ///
  2387.   /// If \p ForAlignof, references are treated like their underlying type
  2388.   /// and  large arrays don't get any special treatment. If not \p ForAlignof
  2389.   /// it computes the value expected by CodeGen: references are treated like
  2390.   /// pointers and large arrays get extra alignment.
  2391.   CharUnits getDeclAlign(const Decl *D, bool ForAlignof = false) const;
  2392.  
  2393.   /// Return the alignment (in bytes) of the thrown exception object. This is
  2394.   /// only meaningful for targets that allocate C++ exceptions in a system
  2395.   /// runtime, such as those using the Itanium C++ ABI.
  2396.   CharUnits getExnObjectAlignment() const;
  2397.  
  2398.   /// Get or compute information about the layout of the specified
  2399.   /// record (struct/union/class) \p D, which indicates its size and field
  2400.   /// position information.
  2401.   const ASTRecordLayout &getASTRecordLayout(const RecordDecl *D) const;
  2402.  
  2403.   /// Get or compute information about the layout of the specified
  2404.   /// Objective-C interface.
  2405.   const ASTRecordLayout &getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D)
  2406.     const;
  2407.  
  2408.   void DumpRecordLayout(const RecordDecl *RD, raw_ostream &OS,
  2409.                         bool Simple = false) const;
  2410.  
  2411.   /// Get or compute information about the layout of the specified
  2412.   /// Objective-C implementation.
  2413.   ///
  2414.   /// This may differ from the interface if synthesized ivars are present.
  2415.   const ASTRecordLayout &
  2416.   getASTObjCImplementationLayout(const ObjCImplementationDecl *D) const;
  2417.  
  2418.   /// Get our current best idea for the key function of the
  2419.   /// given record decl, or nullptr if there isn't one.
  2420.   ///
  2421.   /// The key function is, according to the Itanium C++ ABI section 5.2.3:
  2422.   ///   ...the first non-pure virtual function that is not inline at the
  2423.   ///   point of class definition.
  2424.   ///
  2425.   /// Other ABIs use the same idea.  However, the ARM C++ ABI ignores
  2426.   /// virtual functions that are defined 'inline', which means that
  2427.   /// the result of this computation can change.
  2428.   const CXXMethodDecl *getCurrentKeyFunction(const CXXRecordDecl *RD);
  2429.  
  2430.   /// Observe that the given method cannot be a key function.
  2431.   /// Checks the key-function cache for the method's class and clears it
  2432.   /// if matches the given declaration.
  2433.   ///
  2434.   /// This is used in ABIs where out-of-line definitions marked
  2435.   /// inline are not considered to be key functions.
  2436.   ///
  2437.   /// \param method should be the declaration from the class definition
  2438.   void setNonKeyFunction(const CXXMethodDecl *method);
  2439.  
  2440.   /// Loading virtual member pointers using the virtual inheritance model
  2441.   /// always results in an adjustment using the vbtable even if the index is
  2442.   /// zero.
  2443.   ///
  2444.   /// This is usually OK because the first slot in the vbtable points
  2445.   /// backwards to the top of the MDC.  However, the MDC might be reusing a
  2446.   /// vbptr from an nv-base.  In this case, the first slot in the vbtable
  2447.   /// points to the start of the nv-base which introduced the vbptr and *not*
  2448.   /// the MDC.  Modify the NonVirtualBaseAdjustment to account for this.
  2449.   CharUnits getOffsetOfBaseWithVBPtr(const CXXRecordDecl *RD) const;
  2450.  
  2451.   /// Get the offset of a FieldDecl or IndirectFieldDecl, in bits.
  2452.   uint64_t getFieldOffset(const ValueDecl *FD) const;
  2453.  
  2454.   /// Get the offset of an ObjCIvarDecl in bits.
  2455.   uint64_t lookupFieldBitOffset(const ObjCInterfaceDecl *OID,
  2456.                                 const ObjCImplementationDecl *ID,
  2457.                                 const ObjCIvarDecl *Ivar) const;
  2458.  
  2459.   /// Find the 'this' offset for the member path in a pointer-to-member
  2460.   /// APValue.
  2461.   CharUnits getMemberPointerPathAdjustment(const APValue &MP) const;
  2462.  
  2463.   bool isNearlyEmpty(const CXXRecordDecl *RD) const;
  2464.  
  2465.   VTableContextBase *getVTableContext();
  2466.  
  2467.   /// If \p T is null pointer, assume the target in ASTContext.
  2468.   MangleContext *createMangleContext(const TargetInfo *T = nullptr);
  2469.  
  2470.   /// Creates a device mangle context to correctly mangle lambdas in a mixed
  2471.   /// architecture compile by setting the lambda mangling number source to the
  2472.   /// DeviceLambdaManglingNumber. Currently this asserts that the TargetInfo
  2473.   /// (from the AuxTargetInfo) is a an itanium target.
  2474.   MangleContext *createDeviceMangleContext(const TargetInfo &T);
  2475.  
  2476.   void DeepCollectObjCIvars(const ObjCInterfaceDecl *OI, bool leafClass,
  2477.                             SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const;
  2478.  
  2479.   unsigned CountNonClassIvars(const ObjCInterfaceDecl *OI) const;
  2480.   void CollectInheritedProtocols(const Decl *CDecl,
  2481.                           llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols);
  2482.  
  2483.   /// Return true if the specified type has unique object representations
  2484.   /// according to (C++17 [meta.unary.prop]p9)
  2485.   bool hasUniqueObjectRepresentations(QualType Ty) const;
  2486.  
  2487.   //===--------------------------------------------------------------------===//
  2488.   //                            Type Operators
  2489.   //===--------------------------------------------------------------------===//
  2490.  
  2491.   /// Return the canonical (structural) type corresponding to the
  2492.   /// specified potentially non-canonical type \p T.
  2493.   ///
  2494.   /// The non-canonical version of a type may have many "decorated" versions of
  2495.   /// types.  Decorators can include typedefs, 'typeof' operators, etc. The
  2496.   /// returned type is guaranteed to be free of any of these, allowing two
  2497.   /// canonical types to be compared for exact equality with a simple pointer
  2498.   /// comparison.
  2499.   CanQualType getCanonicalType(QualType T) const {
  2500.     return CanQualType::CreateUnsafe(T.getCanonicalType());
  2501.   }
  2502.  
  2503.   const Type *getCanonicalType(const Type *T) const {
  2504.     return T->getCanonicalTypeInternal().getTypePtr();
  2505.   }
  2506.  
  2507.   /// Return the canonical parameter type corresponding to the specific
  2508.   /// potentially non-canonical one.
  2509.   ///
  2510.   /// Qualifiers are stripped off, functions are turned into function
  2511.   /// pointers, and arrays decay one level into pointers.
  2512.   CanQualType getCanonicalParamType(QualType T) const;
  2513.  
  2514.   /// Determine whether the given types \p T1 and \p T2 are equivalent.
  2515.   bool hasSameType(QualType T1, QualType T2) const {
  2516.     return getCanonicalType(T1) == getCanonicalType(T2);
  2517.   }
  2518.   bool hasSameType(const Type *T1, const Type *T2) const {
  2519.     return getCanonicalType(T1) == getCanonicalType(T2);
  2520.   }
  2521.  
  2522.   /// Determine whether the given expressions \p X and \p Y are equivalent.
  2523.   bool hasSameExpr(const Expr *X, const Expr *Y) const;
  2524.  
  2525.   /// Return this type as a completely-unqualified array type,
  2526.   /// capturing the qualifiers in \p Quals.
  2527.   ///
  2528.   /// This will remove the minimal amount of sugaring from the types, similar
  2529.   /// to the behavior of QualType::getUnqualifiedType().
  2530.   ///
  2531.   /// \param T is the qualified type, which may be an ArrayType
  2532.   ///
  2533.   /// \param Quals will receive the full set of qualifiers that were
  2534.   /// applied to the array.
  2535.   ///
  2536.   /// \returns if this is an array type, the completely unqualified array type
  2537.   /// that corresponds to it. Otherwise, returns T.getUnqualifiedType().
  2538.   QualType getUnqualifiedArrayType(QualType T, Qualifiers &Quals);
  2539.  
  2540.   /// Determine whether the given types are equivalent after
  2541.   /// cvr-qualifiers have been removed.
  2542.   bool hasSameUnqualifiedType(QualType T1, QualType T2) const {
  2543.     return getCanonicalType(T1).getTypePtr() ==
  2544.            getCanonicalType(T2).getTypePtr();
  2545.   }
  2546.  
  2547.   bool hasSameNullabilityTypeQualifier(QualType SubT, QualType SuperT,
  2548.                                        bool IsParam) const {
  2549.     auto SubTnullability = SubT->getNullability();
  2550.     auto SuperTnullability = SuperT->getNullability();
  2551.     if (SubTnullability.has_value() == SuperTnullability.has_value()) {
  2552.       // Neither has nullability; return true
  2553.       if (!SubTnullability)
  2554.         return true;
  2555.       // Both have nullability qualifier.
  2556.       if (*SubTnullability == *SuperTnullability ||
  2557.           *SubTnullability == NullabilityKind::Unspecified ||
  2558.           *SuperTnullability == NullabilityKind::Unspecified)
  2559.         return true;
  2560.  
  2561.       if (IsParam) {
  2562.         // Ok for the superclass method parameter to be "nonnull" and the subclass
  2563.         // method parameter to be "nullable"
  2564.         return (*SuperTnullability == NullabilityKind::NonNull &&
  2565.                 *SubTnullability == NullabilityKind::Nullable);
  2566.       }
  2567.       // For the return type, it's okay for the superclass method to specify
  2568.       // "nullable" and the subclass method specify "nonnull"
  2569.       return (*SuperTnullability == NullabilityKind::Nullable &&
  2570.               *SubTnullability == NullabilityKind::NonNull);
  2571.     }
  2572.     return true;
  2573.   }
  2574.  
  2575.   bool ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
  2576.                            const ObjCMethodDecl *MethodImp);
  2577.  
  2578.   bool UnwrapSimilarTypes(QualType &T1, QualType &T2,
  2579.                           bool AllowPiMismatch = true);
  2580.   void UnwrapSimilarArrayTypes(QualType &T1, QualType &T2,
  2581.                                bool AllowPiMismatch = true);
  2582.  
  2583.   /// Determine if two types are similar, according to the C++ rules. That is,
  2584.   /// determine if they are the same other than qualifiers on the initial
  2585.   /// sequence of pointer / pointer-to-member / array (and in Clang, object
  2586.   /// pointer) types and their element types.
  2587.   ///
  2588.   /// Clang offers a number of qualifiers in addition to the C++ qualifiers;
  2589.   /// those qualifiers are also ignored in the 'similarity' check.
  2590.   bool hasSimilarType(QualType T1, QualType T2);
  2591.  
  2592.   /// Determine if two types are similar, ignoring only CVR qualifiers.
  2593.   bool hasCvrSimilarType(QualType T1, QualType T2);
  2594.  
  2595.   /// Retrieves the "canonical" nested name specifier for a
  2596.   /// given nested name specifier.
  2597.   ///
  2598.   /// The canonical nested name specifier is a nested name specifier
  2599.   /// that uniquely identifies a type or namespace within the type
  2600.   /// system. For example, given:
  2601.   ///
  2602.   /// \code
  2603.   /// namespace N {
  2604.   ///   struct S {
  2605.   ///     template<typename T> struct X { typename T* type; };
  2606.   ///   };
  2607.   /// }
  2608.   ///
  2609.   /// template<typename T> struct Y {
  2610.   ///   typename N::S::X<T>::type member;
  2611.   /// };
  2612.   /// \endcode
  2613.   ///
  2614.   /// Here, the nested-name-specifier for N::S::X<T>:: will be
  2615.   /// S::X<template-param-0-0>, since 'S' and 'X' are uniquely defined
  2616.   /// by declarations in the type system and the canonical type for
  2617.   /// the template type parameter 'T' is template-param-0-0.
  2618.   NestedNameSpecifier *
  2619.   getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const;
  2620.  
  2621.   /// Retrieves the default calling convention for the current target.
  2622.   CallingConv getDefaultCallingConvention(bool IsVariadic,
  2623.                                           bool IsCXXMethod,
  2624.                                           bool IsBuiltin = false) const;
  2625.  
  2626.   /// Retrieves the "canonical" template name that refers to a
  2627.   /// given template.
  2628.   ///
  2629.   /// The canonical template name is the simplest expression that can
  2630.   /// be used to refer to a given template. For most templates, this
  2631.   /// expression is just the template declaration itself. For example,
  2632.   /// the template std::vector can be referred to via a variety of
  2633.   /// names---std::vector, \::std::vector, vector (if vector is in
  2634.   /// scope), etc.---but all of these names map down to the same
  2635.   /// TemplateDecl, which is used to form the canonical template name.
  2636.   ///
  2637.   /// Dependent template names are more interesting. Here, the
  2638.   /// template name could be something like T::template apply or
  2639.   /// std::allocator<T>::template rebind, where the nested name
  2640.   /// specifier itself is dependent. In this case, the canonical
  2641.   /// template name uses the shortest form of the dependent
  2642.   /// nested-name-specifier, which itself contains all canonical
  2643.   /// types, values, and templates.
  2644.   TemplateName getCanonicalTemplateName(const TemplateName &Name) const;
  2645.  
  2646.   /// Determine whether the given template names refer to the same
  2647.   /// template.
  2648.   bool hasSameTemplateName(const TemplateName &X, const TemplateName &Y) const;
  2649.  
  2650.   /// Determine whether two Friend functions are different because constraints
  2651.   /// that refer to an enclosing template, according to [temp.friend] p9.
  2652.   bool FriendsDifferByConstraints(const FunctionDecl *X,
  2653.                                   const FunctionDecl *Y) const;
  2654.  
  2655.   /// Determine whether the two declarations refer to the same entity.
  2656.   bool isSameEntity(const NamedDecl *X, const NamedDecl *Y) const;
  2657.  
  2658.   /// Determine whether two template parameter lists are similar enough
  2659.   /// that they may be used in declarations of the same template.
  2660.   bool isSameTemplateParameterList(const TemplateParameterList *X,
  2661.                                    const TemplateParameterList *Y) const;
  2662.  
  2663.   /// Determine whether two template parameters are similar enough
  2664.   /// that they may be used in declarations of the same template.
  2665.   bool isSameTemplateParameter(const NamedDecl *X, const NamedDecl *Y) const;
  2666.  
  2667.   /// Determine whether two 'requires' expressions are similar enough that they
  2668.   /// may be used in re-declarations.
  2669.   ///
  2670.   /// Use of 'requires' isn't mandatory, works with constraints expressed in
  2671.   /// other ways too.
  2672.   bool isSameConstraintExpr(const Expr *XCE, const Expr *YCE) const;
  2673.  
  2674.   /// Determine whether two type contraint are similar enough that they could
  2675.   /// used in declarations of the same template.
  2676.   bool isSameTypeConstraint(const TypeConstraint *XTC,
  2677.                             const TypeConstraint *YTC) const;
  2678.  
  2679.   /// Determine whether two default template arguments are similar enough
  2680.   /// that they may be used in declarations of the same template.
  2681.   bool isSameDefaultTemplateArgument(const NamedDecl *X,
  2682.                                      const NamedDecl *Y) const;
  2683.  
  2684.   /// Retrieve the "canonical" template argument.
  2685.   ///
  2686.   /// The canonical template argument is the simplest template argument
  2687.   /// (which may be a type, value, expression, or declaration) that
  2688.   /// expresses the value of the argument.
  2689.   TemplateArgument getCanonicalTemplateArgument(const TemplateArgument &Arg)
  2690.     const;
  2691.  
  2692.   /// Type Query functions.  If the type is an instance of the specified class,
  2693.   /// return the Type pointer for the underlying maximally pretty type.  This
  2694.   /// is a member of ASTContext because this may need to do some amount of
  2695.   /// canonicalization, e.g. to move type qualifiers into the element type.
  2696.   const ArrayType *getAsArrayType(QualType T) const;
  2697.   const ConstantArrayType *getAsConstantArrayType(QualType T) const {
  2698.     return dyn_cast_or_null<ConstantArrayType>(getAsArrayType(T));
  2699.   }
  2700.   const VariableArrayType *getAsVariableArrayType(QualType T) const {
  2701.     return dyn_cast_or_null<VariableArrayType>(getAsArrayType(T));
  2702.   }
  2703.   const IncompleteArrayType *getAsIncompleteArrayType(QualType T) const {
  2704.     return dyn_cast_or_null<IncompleteArrayType>(getAsArrayType(T));
  2705.   }
  2706.   const DependentSizedArrayType *getAsDependentSizedArrayType(QualType T)
  2707.     const {
  2708.     return dyn_cast_or_null<DependentSizedArrayType>(getAsArrayType(T));
  2709.   }
  2710.  
  2711.   /// Return the innermost element type of an array type.
  2712.   ///
  2713.   /// For example, will return "int" for int[m][n]
  2714.   QualType getBaseElementType(const ArrayType *VAT) const;
  2715.  
  2716.   /// Return the innermost element type of a type (which needn't
  2717.   /// actually be an array type).
  2718.   QualType getBaseElementType(QualType QT) const;
  2719.  
  2720.   /// Return number of constant array elements.
  2721.   uint64_t getConstantArrayElementCount(const ConstantArrayType *CA) const;
  2722.  
  2723.   /// Return number of elements initialized in an ArrayInitLoopExpr.
  2724.   uint64_t
  2725.   getArrayInitLoopExprElementCount(const ArrayInitLoopExpr *AILE) const;
  2726.  
  2727.   /// Perform adjustment on the parameter type of a function.
  2728.   ///
  2729.   /// This routine adjusts the given parameter type @p T to the actual
  2730.   /// parameter type used by semantic analysis (C99 6.7.5.3p[7,8],
  2731.   /// C++ [dcl.fct]p3). The adjusted parameter type is returned.
  2732.   QualType getAdjustedParameterType(QualType T) const;
  2733.  
  2734.   /// Retrieve the parameter type as adjusted for use in the signature
  2735.   /// of a function, decaying array and function types and removing top-level
  2736.   /// cv-qualifiers.
  2737.   QualType getSignatureParameterType(QualType T) const;
  2738.  
  2739.   QualType getExceptionObjectType(QualType T) const;
  2740.  
  2741.   /// Return the properly qualified result of decaying the specified
  2742.   /// array type to a pointer.
  2743.   ///
  2744.   /// This operation is non-trivial when handling typedefs etc.  The canonical
  2745.   /// type of \p T must be an array type, this returns a pointer to a properly
  2746.   /// qualified element of the array.
  2747.   ///
  2748.   /// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
  2749.   QualType getArrayDecayedType(QualType T) const;
  2750.  
  2751.   /// Return the type that \p PromotableType will promote to: C99
  2752.   /// 6.3.1.1p2, assuming that \p PromotableType is a promotable integer type.
  2753.   QualType getPromotedIntegerType(QualType PromotableType) const;
  2754.  
  2755.   /// Recurses in pointer/array types until it finds an Objective-C
  2756.   /// retainable type and returns its ownership.
  2757.   Qualifiers::ObjCLifetime getInnerObjCOwnership(QualType T) const;
  2758.  
  2759.   /// Whether this is a promotable bitfield reference according
  2760.   /// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
  2761.   ///
  2762.   /// \returns the type this bit-field will promote to, or NULL if no
  2763.   /// promotion occurs.
  2764.   QualType isPromotableBitField(Expr *E) const;
  2765.  
  2766.   /// Return the highest ranked integer type, see C99 6.3.1.8p1.
  2767.   ///
  2768.   /// If \p LHS > \p RHS, returns 1.  If \p LHS == \p RHS, returns 0.  If
  2769.   /// \p LHS < \p RHS, return -1.
  2770.   int getIntegerTypeOrder(QualType LHS, QualType RHS) const;
  2771.  
  2772.   /// Compare the rank of the two specified floating point types,
  2773.   /// ignoring the domain of the type (i.e. 'double' == '_Complex double').
  2774.   ///
  2775.   /// If \p LHS > \p RHS, returns 1.  If \p LHS == \p RHS, returns 0.  If
  2776.   /// \p LHS < \p RHS, return -1.
  2777.   int getFloatingTypeOrder(QualType LHS, QualType RHS) const;
  2778.  
  2779.   /// Compare the rank of two floating point types as above, but compare equal
  2780.   /// if both types have the same floating-point semantics on the target (i.e.
  2781.   /// long double and double on AArch64 will return 0).
  2782.   int getFloatingTypeSemanticOrder(QualType LHS, QualType RHS) const;
  2783.  
  2784.   unsigned getTargetAddressSpace(LangAS AS) const;
  2785.  
  2786.   LangAS getLangASForBuiltinAddressSpace(unsigned AS) const;
  2787.  
  2788.   /// Get target-dependent integer value for null pointer which is used for
  2789.   /// constant folding.
  2790.   uint64_t getTargetNullPointerValue(QualType QT) const;
  2791.  
  2792.   bool addressSpaceMapManglingFor(LangAS AS) const {
  2793.     return AddrSpaceMapMangling || isTargetAddressSpace(AS);
  2794.   }
  2795.  
  2796.   // Merges two exception specifications, such that the resulting
  2797.   // exception spec is the union of both. For example, if either
  2798.   // of them can throw something, the result can throw it as well.
  2799.   FunctionProtoType::ExceptionSpecInfo
  2800.   mergeExceptionSpecs(FunctionProtoType::ExceptionSpecInfo ESI1,
  2801.                       FunctionProtoType::ExceptionSpecInfo ESI2,
  2802.                       SmallVectorImpl<QualType> &ExceptionTypeStorage,
  2803.                       bool AcceptDependent);
  2804.  
  2805.   // For two "same" types, return a type which has
  2806.   // the common sugar between them. If Unqualified is true,
  2807.   // both types need only be the same unqualified type.
  2808.   // The result will drop the qualifiers which do not occur
  2809.   // in both types.
  2810.   QualType getCommonSugaredType(QualType X, QualType Y,
  2811.                                 bool Unqualified = false);
  2812.  
  2813. private:
  2814.   // Helper for integer ordering
  2815.   unsigned getIntegerRank(const Type *T) const;
  2816.  
  2817. public:
  2818.   //===--------------------------------------------------------------------===//
  2819.   //                    Type Compatibility Predicates
  2820.   //===--------------------------------------------------------------------===//
  2821.  
  2822.   /// Compatibility predicates used to check assignment expressions.
  2823.   bool typesAreCompatible(QualType T1, QualType T2,
  2824.                           bool CompareUnqualified = false); // C99 6.2.7p1
  2825.  
  2826.   bool propertyTypesAreCompatible(QualType, QualType);
  2827.   bool typesAreBlockPointerCompatible(QualType, QualType);
  2828.  
  2829.   bool isObjCIdType(QualType T) const {
  2830.     if (const auto *ET = dyn_cast<ElaboratedType>(T))
  2831.       T = ET->getNamedType();
  2832.     return T == getObjCIdType();
  2833.   }
  2834.  
  2835.   bool isObjCClassType(QualType T) const {
  2836.     if (const auto *ET = dyn_cast<ElaboratedType>(T))
  2837.       T = ET->getNamedType();
  2838.     return T == getObjCClassType();
  2839.   }
  2840.  
  2841.   bool isObjCSelType(QualType T) const {
  2842.     if (const auto *ET = dyn_cast<ElaboratedType>(T))
  2843.       T = ET->getNamedType();
  2844.     return T == getObjCSelType();
  2845.   }
  2846.  
  2847.   bool ObjCQualifiedIdTypesAreCompatible(const ObjCObjectPointerType *LHS,
  2848.                                          const ObjCObjectPointerType *RHS,
  2849.                                          bool ForCompare);
  2850.  
  2851.   bool ObjCQualifiedClassTypesAreCompatible(const ObjCObjectPointerType *LHS,
  2852.                                             const ObjCObjectPointerType *RHS);
  2853.  
  2854.   // Check the safety of assignment from LHS to RHS
  2855.   bool canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
  2856.                                const ObjCObjectPointerType *RHSOPT);
  2857.   bool canAssignObjCInterfaces(const ObjCObjectType *LHS,
  2858.                                const ObjCObjectType *RHS);
  2859.   bool canAssignObjCInterfacesInBlockPointer(
  2860.                                           const ObjCObjectPointerType *LHSOPT,
  2861.                                           const ObjCObjectPointerType *RHSOPT,
  2862.                                           bool BlockReturnType);
  2863.   bool areComparableObjCPointerTypes(QualType LHS, QualType RHS);
  2864.   QualType areCommonBaseCompatible(const ObjCObjectPointerType *LHSOPT,
  2865.                                    const ObjCObjectPointerType *RHSOPT);
  2866.   bool canBindObjCObjectType(QualType To, QualType From);
  2867.  
  2868.   // Functions for calculating composite types
  2869.   QualType mergeTypes(QualType, QualType, bool OfBlockPointer = false,
  2870.                       bool Unqualified = false, bool BlockReturnType = false,
  2871.                       bool IsConditionalOperator = false);
  2872.   QualType mergeFunctionTypes(QualType, QualType, bool OfBlockPointer = false,
  2873.                               bool Unqualified = false, bool AllowCXX = false,
  2874.                               bool IsConditionalOperator = false);
  2875.   QualType mergeFunctionParameterTypes(QualType, QualType,
  2876.                                        bool OfBlockPointer = false,
  2877.                                        bool Unqualified = false);
  2878.   QualType mergeTransparentUnionType(QualType, QualType,
  2879.                                      bool OfBlockPointer=false,
  2880.                                      bool Unqualified = false);
  2881.  
  2882.   QualType mergeObjCGCQualifiers(QualType, QualType);
  2883.  
  2884.   /// This function merges the ExtParameterInfo lists of two functions. It
  2885.   /// returns true if the lists are compatible. The merged list is returned in
  2886.   /// NewParamInfos.
  2887.   ///
  2888.   /// \param FirstFnType The type of the first function.
  2889.   ///
  2890.   /// \param SecondFnType The type of the second function.
  2891.   ///
  2892.   /// \param CanUseFirst This flag is set to true if the first function's
  2893.   /// ExtParameterInfo list can be used as the composite list of
  2894.   /// ExtParameterInfo.
  2895.   ///
  2896.   /// \param CanUseSecond This flag is set to true if the second function's
  2897.   /// ExtParameterInfo list can be used as the composite list of
  2898.   /// ExtParameterInfo.
  2899.   ///
  2900.   /// \param NewParamInfos The composite list of ExtParameterInfo. The list is
  2901.   /// empty if none of the flags are set.
  2902.   ///
  2903.   bool mergeExtParameterInfo(
  2904.       const FunctionProtoType *FirstFnType,
  2905.       const FunctionProtoType *SecondFnType,
  2906.       bool &CanUseFirst, bool &CanUseSecond,
  2907.       SmallVectorImpl<FunctionProtoType::ExtParameterInfo> &NewParamInfos);
  2908.  
  2909.   void ResetObjCLayout(const ObjCContainerDecl *CD);
  2910.  
  2911.   //===--------------------------------------------------------------------===//
  2912.   //                    Integer Predicates
  2913.   //===--------------------------------------------------------------------===//
  2914.  
  2915.   // The width of an integer, as defined in C99 6.2.6.2. This is the number
  2916.   // of bits in an integer type excluding any padding bits.
  2917.   unsigned getIntWidth(QualType T) const;
  2918.  
  2919.   // Per C99 6.2.5p6, for every signed integer type, there is a corresponding
  2920.   // unsigned integer type.  This method takes a signed type, and returns the
  2921.   // corresponding unsigned integer type.
  2922.   // With the introduction of fixed point types in ISO N1169, this method also
  2923.   // accepts fixed point types and returns the corresponding unsigned type for
  2924.   // a given fixed point type.
  2925.   QualType getCorrespondingUnsignedType(QualType T) const;
  2926.  
  2927.   // Per C99 6.2.5p6, for every signed integer type, there is a corresponding
  2928.   // unsigned integer type.  This method takes an unsigned type, and returns the
  2929.   // corresponding signed integer type.
  2930.   // With the introduction of fixed point types in ISO N1169, this method also
  2931.   // accepts fixed point types and returns the corresponding signed type for
  2932.   // a given fixed point type.
  2933.   QualType getCorrespondingSignedType(QualType T) const;
  2934.  
  2935.   // Per ISO N1169, this method accepts fixed point types and returns the
  2936.   // corresponding saturated type for a given fixed point type.
  2937.   QualType getCorrespondingSaturatedType(QualType Ty) const;
  2938.  
  2939.   // This method accepts fixed point types and returns the corresponding signed
  2940.   // type. Unlike getCorrespondingUnsignedType(), this only accepts unsigned
  2941.   // fixed point types because there are unsigned integer types like bool and
  2942.   // char8_t that don't have signed equivalents.
  2943.   QualType getCorrespondingSignedFixedPointType(QualType Ty) const;
  2944.  
  2945.   //===--------------------------------------------------------------------===//
  2946.   //                    Integer Values
  2947.   //===--------------------------------------------------------------------===//
  2948.  
  2949.   /// Make an APSInt of the appropriate width and signedness for the
  2950.   /// given \p Value and integer \p Type.
  2951.   llvm::APSInt MakeIntValue(uint64_t Value, QualType Type) const {
  2952.     // If Type is a signed integer type larger than 64 bits, we need to be sure
  2953.     // to sign extend Res appropriately.
  2954.     llvm::APSInt Res(64, !Type->isSignedIntegerOrEnumerationType());
  2955.     Res = Value;
  2956.     unsigned Width = getIntWidth(Type);
  2957.     if (Width != Res.getBitWidth())
  2958.       return Res.extOrTrunc(Width);
  2959.     return Res;
  2960.   }
  2961.  
  2962.   bool isSentinelNullExpr(const Expr *E);
  2963.  
  2964.   /// Get the implementation of the ObjCInterfaceDecl \p D, or nullptr if
  2965.   /// none exists.
  2966.   ObjCImplementationDecl *getObjCImplementation(ObjCInterfaceDecl *D);
  2967.  
  2968.   /// Get the implementation of the ObjCCategoryDecl \p D, or nullptr if
  2969.   /// none exists.
  2970.   ObjCCategoryImplDecl *getObjCImplementation(ObjCCategoryDecl *D);
  2971.  
  2972.   /// Return true if there is at least one \@implementation in the TU.
  2973.   bool AnyObjCImplementation() {
  2974.     return !ObjCImpls.empty();
  2975.   }
  2976.  
  2977.   /// Set the implementation of ObjCInterfaceDecl.
  2978.   void setObjCImplementation(ObjCInterfaceDecl *IFaceD,
  2979.                              ObjCImplementationDecl *ImplD);
  2980.  
  2981.   /// Set the implementation of ObjCCategoryDecl.
  2982.   void setObjCImplementation(ObjCCategoryDecl *CatD,
  2983.                              ObjCCategoryImplDecl *ImplD);
  2984.  
  2985.   /// Get the duplicate declaration of a ObjCMethod in the same
  2986.   /// interface, or null if none exists.
  2987.   const ObjCMethodDecl *
  2988.   getObjCMethodRedeclaration(const ObjCMethodDecl *MD) const;
  2989.  
  2990.   void setObjCMethodRedeclaration(const ObjCMethodDecl *MD,
  2991.                                   const ObjCMethodDecl *Redecl);
  2992.  
  2993.   /// Returns the Objective-C interface that \p ND belongs to if it is
  2994.   /// an Objective-C method/property/ivar etc. that is part of an interface,
  2995.   /// otherwise returns null.
  2996.   const ObjCInterfaceDecl *getObjContainingInterface(const NamedDecl *ND) const;
  2997.  
  2998.   /// Set the copy initialization expression of a block var decl. \p CanThrow
  2999.   /// indicates whether the copy expression can throw or not.
  3000.   void setBlockVarCopyInit(const VarDecl* VD, Expr *CopyExpr, bool CanThrow);
  3001.  
  3002.   /// Get the copy initialization expression of the VarDecl \p VD, or
  3003.   /// nullptr if none exists.
  3004.   BlockVarCopyInit getBlockVarCopyInit(const VarDecl* VD) const;
  3005.  
  3006.   /// Allocate an uninitialized TypeSourceInfo.
  3007.   ///
  3008.   /// The caller should initialize the memory held by TypeSourceInfo using
  3009.   /// the TypeLoc wrappers.
  3010.   ///
  3011.   /// \param T the type that will be the basis for type source info. This type
  3012.   /// should refer to how the declarator was written in source code, not to
  3013.   /// what type semantic analysis resolved the declarator to.
  3014.   ///
  3015.   /// \param Size the size of the type info to create, or 0 if the size
  3016.   /// should be calculated based on the type.
  3017.   TypeSourceInfo *CreateTypeSourceInfo(QualType T, unsigned Size = 0) const;
  3018.  
  3019.   /// Allocate a TypeSourceInfo where all locations have been
  3020.   /// initialized to a given location, which defaults to the empty
  3021.   /// location.
  3022.   TypeSourceInfo *
  3023.   getTrivialTypeSourceInfo(QualType T,
  3024.                            SourceLocation Loc = SourceLocation()) const;
  3025.  
  3026.   /// Add a deallocation callback that will be invoked when the
  3027.   /// ASTContext is destroyed.
  3028.   ///
  3029.   /// \param Callback A callback function that will be invoked on destruction.
  3030.   ///
  3031.   /// \param Data Pointer data that will be provided to the callback function
  3032.   /// when it is called.
  3033.   void AddDeallocation(void (*Callback)(void *), void *Data) const;
  3034.  
  3035.   /// If T isn't trivially destructible, calls AddDeallocation to register it
  3036.   /// for destruction.
  3037.   template <typename T> void addDestruction(T *Ptr) const {
  3038.     if (!std::is_trivially_destructible<T>::value) {
  3039.       auto DestroyPtr = [](void *V) { static_cast<T *>(V)->~T(); };
  3040.       AddDeallocation(DestroyPtr, Ptr);
  3041.     }
  3042.   }
  3043.  
  3044.   GVALinkage GetGVALinkageForFunction(const FunctionDecl *FD) const;
  3045.   GVALinkage GetGVALinkageForVariable(const VarDecl *VD);
  3046.  
  3047.   /// Determines if the decl can be CodeGen'ed or deserialized from PCH
  3048.   /// lazily, only when used; this is only relevant for function or file scoped
  3049.   /// var definitions.
  3050.   ///
  3051.   /// \returns true if the function/var must be CodeGen'ed/deserialized even if
  3052.   /// it is not used.
  3053.   bool DeclMustBeEmitted(const Decl *D);
  3054.  
  3055.   /// Visits all versions of a multiversioned function with the passed
  3056.   /// predicate.
  3057.   void forEachMultiversionedFunctionVersion(
  3058.       const FunctionDecl *FD,
  3059.       llvm::function_ref<void(FunctionDecl *)> Pred) const;
  3060.  
  3061.   const CXXConstructorDecl *
  3062.   getCopyConstructorForExceptionObject(CXXRecordDecl *RD);
  3063.  
  3064.   void addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
  3065.                                             CXXConstructorDecl *CD);
  3066.  
  3067.   void addTypedefNameForUnnamedTagDecl(TagDecl *TD, TypedefNameDecl *TND);
  3068.  
  3069.   TypedefNameDecl *getTypedefNameForUnnamedTagDecl(const TagDecl *TD);
  3070.  
  3071.   void addDeclaratorForUnnamedTagDecl(TagDecl *TD, DeclaratorDecl *DD);
  3072.  
  3073.   DeclaratorDecl *getDeclaratorForUnnamedTagDecl(const TagDecl *TD);
  3074.  
  3075.   void setManglingNumber(const NamedDecl *ND, unsigned Number);
  3076.   unsigned getManglingNumber(const NamedDecl *ND,
  3077.                              bool ForAuxTarget = false) const;
  3078.  
  3079.   void setStaticLocalNumber(const VarDecl *VD, unsigned Number);
  3080.   unsigned getStaticLocalNumber(const VarDecl *VD) const;
  3081.  
  3082.   /// Retrieve the context for computing mangling numbers in the given
  3083.   /// DeclContext.
  3084.   MangleNumberingContext &getManglingNumberContext(const DeclContext *DC);
  3085.   enum NeedExtraManglingDecl_t { NeedExtraManglingDecl };
  3086.   MangleNumberingContext &getManglingNumberContext(NeedExtraManglingDecl_t,
  3087.                                                    const Decl *D);
  3088.  
  3089.   std::unique_ptr<MangleNumberingContext> createMangleNumberingContext() const;
  3090.  
  3091.   /// Used by ParmVarDecl to store on the side the
  3092.   /// index of the parameter when it exceeds the size of the normal bitfield.
  3093.   void setParameterIndex(const ParmVarDecl *D, unsigned index);
  3094.  
  3095.   /// Used by ParmVarDecl to retrieve on the side the
  3096.   /// index of the parameter when it exceeds the size of the normal bitfield.
  3097.   unsigned getParameterIndex(const ParmVarDecl *D) const;
  3098.  
  3099.   /// Return a string representing the human readable name for the specified
  3100.   /// function declaration or file name. Used by SourceLocExpr and
  3101.   /// PredefinedExpr to cache evaluated results.
  3102.   StringLiteral *getPredefinedStringLiteralFromCache(StringRef Key) const;
  3103.  
  3104.   /// Return a declaration for the global GUID object representing the given
  3105.   /// GUID value.
  3106.   MSGuidDecl *getMSGuidDecl(MSGuidDeclParts Parts) const;
  3107.  
  3108.   /// Return a declaration for a uniquified anonymous global constant
  3109.   /// corresponding to a given APValue.
  3110.   UnnamedGlobalConstantDecl *
  3111.   getUnnamedGlobalConstantDecl(QualType Ty, const APValue &Value) const;
  3112.  
  3113.   /// Return the template parameter object of the given type with the given
  3114.   /// value.
  3115.   TemplateParamObjectDecl *getTemplateParamObjectDecl(QualType T,
  3116.                                                       const APValue &V) const;
  3117.  
  3118.   /// Parses the target attributes passed in, and returns only the ones that are
  3119.   /// valid feature names.
  3120.   ParsedTargetAttr filterFunctionTargetAttrs(const TargetAttr *TD) const;
  3121.  
  3122.   std::vector<std::string>
  3123.   filterFunctionTargetVersionAttrs(const TargetVersionAttr *TV) const;
  3124.  
  3125.   void getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
  3126.                              const FunctionDecl *) const;
  3127.   void getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
  3128.                              GlobalDecl GD) const;
  3129.  
  3130.   //===--------------------------------------------------------------------===//
  3131.   //                    Statistics
  3132.   //===--------------------------------------------------------------------===//
  3133.  
  3134.   /// The number of implicitly-declared default constructors.
  3135.   unsigned NumImplicitDefaultConstructors = 0;
  3136.  
  3137.   /// The number of implicitly-declared default constructors for
  3138.   /// which declarations were built.
  3139.   unsigned NumImplicitDefaultConstructorsDeclared = 0;
  3140.  
  3141.   /// The number of implicitly-declared copy constructors.
  3142.   unsigned NumImplicitCopyConstructors = 0;
  3143.  
  3144.   /// The number of implicitly-declared copy constructors for
  3145.   /// which declarations were built.
  3146.   unsigned NumImplicitCopyConstructorsDeclared = 0;
  3147.  
  3148.   /// The number of implicitly-declared move constructors.
  3149.   unsigned NumImplicitMoveConstructors = 0;
  3150.  
  3151.   /// The number of implicitly-declared move constructors for
  3152.   /// which declarations were built.
  3153.   unsigned NumImplicitMoveConstructorsDeclared = 0;
  3154.  
  3155.   /// The number of implicitly-declared copy assignment operators.
  3156.   unsigned NumImplicitCopyAssignmentOperators = 0;
  3157.  
  3158.   /// The number of implicitly-declared copy assignment operators for
  3159.   /// which declarations were built.
  3160.   unsigned NumImplicitCopyAssignmentOperatorsDeclared = 0;
  3161.  
  3162.   /// The number of implicitly-declared move assignment operators.
  3163.   unsigned NumImplicitMoveAssignmentOperators = 0;
  3164.  
  3165.   /// The number of implicitly-declared move assignment operators for
  3166.   /// which declarations were built.
  3167.   unsigned NumImplicitMoveAssignmentOperatorsDeclared = 0;
  3168.  
  3169.   /// The number of implicitly-declared destructors.
  3170.   unsigned NumImplicitDestructors = 0;
  3171.  
  3172.   /// The number of implicitly-declared destructors for which
  3173.   /// declarations were built.
  3174.   unsigned NumImplicitDestructorsDeclared = 0;
  3175.  
  3176. public:
  3177.   /// Initialize built-in types.
  3178.   ///
  3179.   /// This routine may only be invoked once for a given ASTContext object.
  3180.   /// It is normally invoked after ASTContext construction.
  3181.   ///
  3182.   /// \param Target The target
  3183.   void InitBuiltinTypes(const TargetInfo &Target,
  3184.                         const TargetInfo *AuxTarget = nullptr);
  3185.  
  3186. private:
  3187.   void InitBuiltinType(CanQualType &R, BuiltinType::Kind K);
  3188.  
  3189.   class ObjCEncOptions {
  3190.     unsigned Bits;
  3191.  
  3192.     ObjCEncOptions(unsigned Bits) : Bits(Bits) {}
  3193.  
  3194.   public:
  3195.     ObjCEncOptions() : Bits(0) {}
  3196.     ObjCEncOptions(const ObjCEncOptions &RHS) : Bits(RHS.Bits) {}
  3197.  
  3198. #define OPT_LIST(V)                                                            \
  3199.   V(ExpandPointedToStructures, 0)                                              \
  3200.   V(ExpandStructures, 1)                                                       \
  3201.   V(IsOutermostType, 2)                                                        \
  3202.   V(EncodingProperty, 3)                                                       \
  3203.   V(IsStructField, 4)                                                          \
  3204.   V(EncodeBlockParameters, 5)                                                  \
  3205.   V(EncodeClassNames, 6)                                                       \
  3206.  
  3207. #define V(N,I) ObjCEncOptions& set##N() { Bits |= 1 << I; return *this; }
  3208. OPT_LIST(V)
  3209. #undef V
  3210.  
  3211. #define V(N,I) bool N() const { return Bits & 1 << I; }
  3212. OPT_LIST(V)
  3213. #undef V
  3214.  
  3215. #undef OPT_LIST
  3216.  
  3217.     [[nodiscard]] ObjCEncOptions keepingOnly(ObjCEncOptions Mask) const {
  3218.       return Bits & Mask.Bits;
  3219.     }
  3220.  
  3221.     [[nodiscard]] ObjCEncOptions forComponentType() const {
  3222.       ObjCEncOptions Mask = ObjCEncOptions()
  3223.                                 .setIsOutermostType()
  3224.                                 .setIsStructField();
  3225.       return Bits & ~Mask.Bits;
  3226.     }
  3227.   };
  3228.  
  3229.   // Return the Objective-C type encoding for a given type.
  3230.   void getObjCEncodingForTypeImpl(QualType t, std::string &S,
  3231.                                   ObjCEncOptions Options,
  3232.                                   const FieldDecl *Field,
  3233.                                   QualType *NotEncodedT = nullptr) const;
  3234.  
  3235.   // Adds the encoding of the structure's members.
  3236.   void getObjCEncodingForStructureImpl(RecordDecl *RD, std::string &S,
  3237.                                        const FieldDecl *Field,
  3238.                                        bool includeVBases = true,
  3239.                                        QualType *NotEncodedT=nullptr) const;
  3240.  
  3241. public:
  3242.   // Adds the encoding of a method parameter or return type.
  3243.   void getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
  3244.                                          QualType T, std::string& S,
  3245.                                          bool Extended) const;
  3246.  
  3247.   /// Returns true if this is an inline-initialized static data member
  3248.   /// which is treated as a definition for MSVC compatibility.
  3249.   bool isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const;
  3250.  
  3251.   enum class InlineVariableDefinitionKind {
  3252.     /// Not an inline variable.
  3253.     None,
  3254.  
  3255.     /// Weak definition of inline variable.
  3256.     Weak,
  3257.  
  3258.     /// Weak for now, might become strong later in this TU.
  3259.     WeakUnknown,
  3260.  
  3261.     /// Strong definition.
  3262.     Strong
  3263.   };
  3264.  
  3265.   /// Determine whether a definition of this inline variable should
  3266.   /// be treated as a weak or strong definition. For compatibility with
  3267.   /// C++14 and before, for a constexpr static data member, if there is an
  3268.   /// out-of-line declaration of the member, we may promote it from weak to
  3269.   /// strong.
  3270.   InlineVariableDefinitionKind
  3271.   getInlineVariableDefinitionKind(const VarDecl *VD) const;
  3272.  
  3273. private:
  3274.   friend class DeclarationNameTable;
  3275.   friend class DeclContext;
  3276.  
  3277.   const ASTRecordLayout &
  3278.   getObjCLayout(const ObjCInterfaceDecl *D,
  3279.                 const ObjCImplementationDecl *Impl) const;
  3280.  
  3281.   /// A set of deallocations that should be performed when the
  3282.   /// ASTContext is destroyed.
  3283.   // FIXME: We really should have a better mechanism in the ASTContext to
  3284.   // manage running destructors for types which do variable sized allocation
  3285.   // within the AST. In some places we thread the AST bump pointer allocator
  3286.   // into the datastructures which avoids this mess during deallocation but is
  3287.   // wasteful of memory, and here we require a lot of error prone book keeping
  3288.   // in order to track and run destructors while we're tearing things down.
  3289.   using DeallocationFunctionsAndArguments =
  3290.       llvm::SmallVector<std::pair<void (*)(void *), void *>, 16>;
  3291.   mutable DeallocationFunctionsAndArguments Deallocations;
  3292.  
  3293.   // FIXME: This currently contains the set of StoredDeclMaps used
  3294.   // by DeclContext objects.  This probably should not be in ASTContext,
  3295.   // but we include it here so that ASTContext can quickly deallocate them.
  3296.   llvm::PointerIntPair<StoredDeclsMap *, 1> LastSDM;
  3297.  
  3298.   std::vector<Decl *> TraversalScope;
  3299.  
  3300.   std::unique_ptr<VTableContextBase> VTContext;
  3301.  
  3302.   void ReleaseDeclContextMaps();
  3303.  
  3304. public:
  3305.   enum PragmaSectionFlag : unsigned {
  3306.     PSF_None = 0,
  3307.     PSF_Read = 0x1,
  3308.     PSF_Write = 0x2,
  3309.     PSF_Execute = 0x4,
  3310.     PSF_Implicit = 0x8,
  3311.     PSF_ZeroInit = 0x10,
  3312.     PSF_Invalid = 0x80000000U,
  3313.   };
  3314.  
  3315.   struct SectionInfo {
  3316.     NamedDecl *Decl;
  3317.     SourceLocation PragmaSectionLocation;
  3318.     int SectionFlags;
  3319.  
  3320.     SectionInfo() = default;
  3321.     SectionInfo(NamedDecl *Decl, SourceLocation PragmaSectionLocation,
  3322.                 int SectionFlags)
  3323.         : Decl(Decl), PragmaSectionLocation(PragmaSectionLocation),
  3324.           SectionFlags(SectionFlags) {}
  3325.   };
  3326.  
  3327.   llvm::StringMap<SectionInfo> SectionInfos;
  3328.  
  3329.   /// Return a new OMPTraitInfo object owned by this context.
  3330.   OMPTraitInfo &getNewOMPTraitInfo();
  3331.  
  3332.   /// Whether a C++ static variable or CUDA/HIP kernel may be externalized.
  3333.   bool mayExternalize(const Decl *D) const;
  3334.  
  3335.   /// Whether a C++ static variable or CUDA/HIP kernel should be externalized.
  3336.   bool shouldExternalize(const Decl *D) const;
  3337.  
  3338.   StringRef getCUIDHash() const;
  3339.  
  3340. private:
  3341.   /// All OMPTraitInfo objects live in this collection, one per
  3342.   /// `pragma omp [begin] declare variant` directive.
  3343.   SmallVector<std::unique_ptr<OMPTraitInfo>, 4> OMPTraitInfoVector;
  3344. };
  3345.  
  3346. /// Insertion operator for diagnostics.
  3347. const StreamingDiagnostic &operator<<(const StreamingDiagnostic &DB,
  3348.                                       const ASTContext::SectionInfo &Section);
  3349.  
  3350. /// Utility function for constructing a nullary selector.
  3351. inline Selector GetNullarySelector(StringRef name, ASTContext &Ctx) {
  3352.   IdentifierInfo* II = &Ctx.Idents.get(name);
  3353.   return Ctx.Selectors.getSelector(0, &II);
  3354. }
  3355.  
  3356. /// Utility function for constructing an unary selector.
  3357. inline Selector GetUnarySelector(StringRef name, ASTContext &Ctx) {
  3358.   IdentifierInfo* II = &Ctx.Idents.get(name);
  3359.   return Ctx.Selectors.getSelector(1, &II);
  3360. }
  3361.  
  3362. } // namespace clang
  3363.  
  3364. // operator new and delete aren't allowed inside namespaces.
  3365.  
  3366. /// Placement new for using the ASTContext's allocator.
  3367. ///
  3368. /// This placement form of operator new uses the ASTContext's allocator for
  3369. /// obtaining memory.
  3370. ///
  3371. /// IMPORTANT: These are also declared in clang/AST/ASTContextAllocate.h!
  3372. /// Any changes here need to also be made there.
  3373. ///
  3374. /// We intentionally avoid using a nothrow specification here so that the calls
  3375. /// to this operator will not perform a null check on the result -- the
  3376. /// underlying allocator never returns null pointers.
  3377. ///
  3378. /// Usage looks like this (assuming there's an ASTContext 'Context' in scope):
  3379. /// @code
  3380. /// // Default alignment (8)
  3381. /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
  3382. /// // Specific alignment
  3383. /// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments);
  3384. /// @endcode
  3385. /// Memory allocated through this placement new operator does not need to be
  3386. /// explicitly freed, as ASTContext will free all of this memory when it gets
  3387. /// destroyed. Please note that you cannot use delete on the pointer.
  3388. ///
  3389. /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
  3390. /// @param C The ASTContext that provides the allocator.
  3391. /// @param Alignment The alignment of the allocated memory (if the underlying
  3392. ///                  allocator supports it).
  3393. /// @return The allocated memory. Could be nullptr.
  3394. inline void *operator new(size_t Bytes, const clang::ASTContext &C,
  3395.                           size_t Alignment /* = 8 */) {
  3396.   return C.Allocate(Bytes, Alignment);
  3397. }
  3398.  
  3399. /// Placement delete companion to the new above.
  3400. ///
  3401. /// This operator is just a companion to the new above. There is no way of
  3402. /// invoking it directly; see the new operator for more details. This operator
  3403. /// is called implicitly by the compiler if a placement new expression using
  3404. /// the ASTContext throws in the object constructor.
  3405. inline void operator delete(void *Ptr, const clang::ASTContext &C, size_t) {
  3406.   C.Deallocate(Ptr);
  3407. }
  3408.  
  3409. /// This placement form of operator new[] uses the ASTContext's allocator for
  3410. /// obtaining memory.
  3411. ///
  3412. /// We intentionally avoid using a nothrow specification here so that the calls
  3413. /// to this operator will not perform a null check on the result -- the
  3414. /// underlying allocator never returns null pointers.
  3415. ///
  3416. /// Usage looks like this (assuming there's an ASTContext 'Context' in scope):
  3417. /// @code
  3418. /// // Default alignment (8)
  3419. /// char *data = new (Context) char[10];
  3420. /// // Specific alignment
  3421. /// char *data = new (Context, 4) char[10];
  3422. /// @endcode
  3423. /// Memory allocated through this placement new[] operator does not need to be
  3424. /// explicitly freed, as ASTContext will free all of this memory when it gets
  3425. /// destroyed. Please note that you cannot use delete on the pointer.
  3426. ///
  3427. /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
  3428. /// @param C The ASTContext that provides the allocator.
  3429. /// @param Alignment The alignment of the allocated memory (if the underlying
  3430. ///                  allocator supports it).
  3431. /// @return The allocated memory. Could be nullptr.
  3432. inline void *operator new[](size_t Bytes, const clang::ASTContext& C,
  3433.                             size_t Alignment /* = 8 */) {
  3434.   return C.Allocate(Bytes, Alignment);
  3435. }
  3436.  
  3437. /// Placement delete[] companion to the new[] above.
  3438. ///
  3439. /// This operator is just a companion to the new[] above. There is no way of
  3440. /// invoking it directly; see the new[] operator for more details. This operator
  3441. /// is called implicitly by the compiler if a placement new[] expression using
  3442. /// the ASTContext throws in the object constructor.
  3443. inline void operator delete[](void *Ptr, const clang::ASTContext &C, size_t) {
  3444.   C.Deallocate(Ptr);
  3445. }
  3446.  
  3447. /// Create the representation of a LazyGenerationalUpdatePtr.
  3448. template <typename Owner, typename T,
  3449.           void (clang::ExternalASTSource::*Update)(Owner)>
  3450. typename clang::LazyGenerationalUpdatePtr<Owner, T, Update>::ValueType
  3451.     clang::LazyGenerationalUpdatePtr<Owner, T, Update>::makeValue(
  3452.         const clang::ASTContext &Ctx, T Value) {
  3453.   // Note, this is implemented here so that ExternalASTSource.h doesn't need to
  3454.   // include ASTContext.h. We explicitly instantiate it for all relevant types
  3455.   // in ASTContext.cpp.
  3456.   if (auto *Source = Ctx.getExternalSource())
  3457.     return new (Ctx) LazyData(Source, Value);
  3458.   return Value;
  3459. }
  3460.  
  3461. #endif // LLVM_CLANG_AST_ASTCONTEXT_H
  3462.