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