xref: /openbsd-src/gnu/llvm/clang/lib/AST/Interp/Record.h (revision 12c855180aad702bbcca06e0398d774beeafb155)
1 //===--- Record.h - struct and class metadata for the VM --------*- 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 // A record is part of a program to describe the layout and methods of a struct.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_AST_INTERP_RECORD_H
14 #define LLVM_CLANG_AST_INTERP_RECORD_H
15 
16 #include "Descriptor.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclCXX.h"
19 
20 namespace clang {
21 namespace interp {
22 class Program;
23 
24 /// Structure/Class descriptor.
25 class Record final {
26 public:
27   /// Describes a record field.
28   struct Field {
29     const FieldDecl *Decl;
30     unsigned Offset;
31     Descriptor *Desc;
32   };
33 
34   /// Describes a base class.
35   struct Base {
36     const RecordDecl *Decl;
37     unsigned Offset;
38     Descriptor *Desc;
39     Record *R;
40   };
41 
42   /// Mapping from identifiers to field descriptors.
43   using FieldList = llvm::SmallVector<Field, 8>;
44   /// Mapping from identifiers to base classes.
45   using BaseList = llvm::SmallVector<Base, 8>;
46   /// List of virtual base classes.
47   using VirtualBaseList = llvm::SmallVector<Base, 2>;
48 
49 public:
50   /// Returns the underlying declaration.
getDecl()51   const RecordDecl *getDecl() const { return Decl; }
52   /// Returns the name of the underlying declaration.
getName()53   const std::string getName() const { return Decl->getNameAsString(); }
54   /// Checks if the record is a union.
isUnion()55   bool isUnion() const { return getDecl()->isUnion(); }
56   /// Returns the size of the record.
getSize()57   unsigned getSize() const { return BaseSize; }
58   /// Returns the full size of the record, including records.
getFullSize()59   unsigned getFullSize() const { return BaseSize + VirtualSize; }
60   /// Returns a field.
61   const Field *getField(const FieldDecl *FD) const;
62   /// Returns a base descriptor.
63   const Base *getBase(const RecordDecl *FD) const;
64   /// Returns a virtual base descriptor.
65   const Base *getVirtualBase(const RecordDecl *RD) const;
66   // Returns the destructor of the record, if any.
getDestructor()67   const CXXDestructorDecl *getDestructor() const {
68     if (const auto *CXXDecl = dyn_cast<CXXRecordDecl>(Decl))
69       return CXXDecl->getDestructor();
70     return nullptr;
71   }
72 
73   using const_field_iter = FieldList::const_iterator;
fields()74   llvm::iterator_range<const_field_iter> fields() const {
75     return llvm::make_range(Fields.begin(), Fields.end());
76   }
77 
getNumFields()78   unsigned getNumFields() const { return Fields.size(); }
getField(unsigned I)79   const Field *getField(unsigned I) const { return &Fields[I]; }
getField(unsigned I)80   Field *getField(unsigned I) { return &Fields[I]; }
81 
82   using const_base_iter = BaseList::const_iterator;
bases()83   llvm::iterator_range<const_base_iter> bases() const {
84     return llvm::make_range(Bases.begin(), Bases.end());
85   }
86 
getNumBases()87   unsigned getNumBases() const { return Bases.size(); }
getBase(unsigned I)88   Base *getBase(unsigned I) { return &Bases[I]; }
89 
90   using const_virtual_iter = VirtualBaseList::const_iterator;
virtual_bases()91   llvm::iterator_range<const_virtual_iter> virtual_bases() const {
92     return llvm::make_range(VirtualBases.begin(), VirtualBases.end());
93   }
94 
getNumVirtualBases()95   unsigned getNumVirtualBases() const { return VirtualBases.size(); }
getVirtualBase(unsigned I)96   Base *getVirtualBase(unsigned I) { return &VirtualBases[I]; }
97 
98 private:
99   /// Constructor used by Program to create record descriptors.
100   Record(const RecordDecl *, BaseList &&Bases, FieldList &&Fields,
101          VirtualBaseList &&VirtualBases, unsigned VirtualSize,
102          unsigned BaseSize);
103 
104 private:
105   friend class Program;
106 
107   /// Original declaration.
108   const RecordDecl *Decl;
109   /// List of all base classes.
110   BaseList Bases;
111   /// List of all the fields in the record.
112   FieldList Fields;
113   /// List o fall virtual bases.
114   VirtualBaseList VirtualBases;
115 
116   /// Mapping from declarations to bases.
117   llvm::DenseMap<const RecordDecl *, Base *> BaseMap;
118   /// Mapping from field identifiers to descriptors.
119   llvm::DenseMap<const FieldDecl *, Field *> FieldMap;
120   /// Mapping from declarations to virtual bases.
121   llvm::DenseMap<const RecordDecl *, Base *> VirtualBaseMap;
122   /// Size of the structure.
123   unsigned BaseSize;
124   /// Size of all virtual bases.
125   unsigned VirtualSize;
126 };
127 
128 } // namespace interp
129 } // namespace clang
130 
131 #endif
132