1 //===- CXXFieldCollector.h - Utility class for C++ class semantic analysis ===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file provides CXXFieldCollector that is used during parsing & semantic
11 //  analysis of C++ classes.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_SEMA_CXXFIELDCOLLECTOR_H
16 #define LLVM_CLANG_SEMA_CXXFIELDCOLLECTOR_H
17 
18 #include "clang/Basic/LLVM.h"
19 #include "llvm/ADT/SmallVector.h"
20 
21 namespace clang {
22   class FieldDecl;
23 
24 /// CXXFieldCollector - Used to keep track of CXXFieldDecls during parsing of
25 /// C++ classes.
26 class CXXFieldCollector {
27   /// Fields - Contains all FieldDecls collected during parsing of a C++
28   /// class. When a nested class is entered, its fields are appended to the
29   /// fields of its parent class, when it is exited its fields are removed.
30   SmallVector<FieldDecl*, 32> Fields;
31 
32   /// FieldCount - Each entry represents the number of fields collected during
33   /// the parsing of a C++ class. When a nested class is entered, a new field
34   /// count is pushed, when it is exited, the field count is popped.
35   SmallVector<size_t, 4> FieldCount;
36 
37   // Example:
38   //
39   // class C {
40   //   int x,y;
41   //   class NC {
42   //     int q;
43   //     // At this point, Fields contains [x,y,q] decls and FieldCount contains
44   //     // [2,1].
45   //   };
46   //   int z;
47   //   // At this point, Fields contains [x,y,z] decls and FieldCount contains
48   //   // [3].
49   // };
50 
51 public:
52   /// StartClass - Called by Sema::ActOnStartCXXClassDef.
StartClass()53   void StartClass() { FieldCount.push_back(0); }
54 
55   /// Add - Called by Sema::ActOnCXXMemberDeclarator.
Add(FieldDecl * D)56   void Add(FieldDecl *D) {
57     Fields.push_back(D);
58     ++FieldCount.back();
59   }
60 
61   /// getCurNumField - The number of fields added to the currently parsed class.
getCurNumFields()62   size_t getCurNumFields() const {
63     assert(!FieldCount.empty() && "no currently-parsed class");
64     return FieldCount.back();
65   }
66 
67   /// getCurFields - Pointer to array of fields added to the currently parsed
68   /// class.
getCurFields()69   FieldDecl **getCurFields() { return &*(Fields.end() - getCurNumFields()); }
70 
71   /// FinishClass - Called by Sema::ActOnFinishCXXClassDef.
FinishClass()72   void FinishClass() {
73     Fields.resize(Fields.size() - getCurNumFields());
74     FieldCount.pop_back();
75   }
76 };
77 
78 } // end namespace clang
79 
80 #endif
81