clang  6.0.0svn
ODRHash.h
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1 //===-- ODRHash.h - Hashing to diagnose ODR failures ------------*- C++ -*-===//
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 /// \file
11 /// This file contains the declaration of the ODRHash class, which calculates
12 /// a hash based on AST nodes, which is stable across different runs.
13 ///
14 //===----------------------------------------------------------------------===//
15 
17 #include "clang/AST/Type.h"
18 #include "clang/AST/TemplateBase.h"
19 #include "llvm/ADT/DenseMap.h"
20 #include "llvm/ADT/FoldingSet.h"
21 #include "llvm/ADT/PointerUnion.h"
22 #include "llvm/ADT/SmallVector.h"
23 
24 namespace clang {
25 
26 class Decl;
27 class IdentifierInfo;
28 class NestedNameSpecifier;
29 class Stmt;
30 class TemplateParameterList;
31 
32 // ODRHash is used to calculate a hash based on AST node contents that
33 // does not rely on pointer addresses. This allows the hash to not vary
34 // between runs and is usable to detect ODR problems in modules. To use,
35 // construct an ODRHash object, then call Add* methods over the nodes that
36 // need to be hashed. Then call CalculateHash to get the hash value.
37 // Typically, only one Add* call is needed. clear can be called to reuse the
38 // object.
39 class ODRHash {
40  // Use DenseMaps to convert between Decl and Type pointers and an index value.
41  llvm::DenseMap<const Decl*, unsigned> DeclMap;
42  llvm::DenseMap<const Type*, unsigned> TypeMap;
43 
44  // Save space by processing bools at the end.
46 
47  llvm::FoldingSetNodeID ID;
48 
49 public:
50  ODRHash() {}
51 
52  // Use this for ODR checking classes between modules. This method compares
53  // more information than the AddDecl class.
54  void AddCXXRecordDecl(const CXXRecordDecl *Record);
55 
56  // Process SubDecls of the main Decl. This method calls the DeclVisitor
57  // while AddDecl does not.
58  void AddSubDecl(const Decl *D);
59 
60  // Reset the object for reuse.
61  void clear();
62 
63  // Add booleans to ID and uses it to calculate the hash.
64  unsigned CalculateHash();
65 
66  // Add AST nodes that need to be processed.
67  void AddDecl(const Decl *D);
68  void AddType(const Type *T);
69  void AddQualType(QualType T);
70  void AddStmt(const Stmt *S);
71  void AddIdentifierInfo(const IdentifierInfo *II);
73  void AddTemplateName(TemplateName Name);
77 
78  // Save booleans until the end to lower the size of data to process.
79  void AddBoolean(bool value);
80 
81  static bool isWhitelistedDecl(const Decl* D, const CXXRecordDecl *Record);
82 };
83 
84 } // end namespace clang
A (possibly-)qualified type.
Definition: Type.h:614
void AddBoolean(bool value)
Definition: ODRHash.cpp:699
Stmt - This represents one statement.
Definition: Stmt.h:60
void AddQualType(QualType T)
Definition: ODRHash.cpp:690
C Language Family Type Representation.
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:81
The base class of the type hierarchy.
Definition: Type.h:1300
The l-value was an access to a declared entity or something equivalently strong, like the address of ...
Stores a list of template parameters for a TemplateDecl and its derived classes.
Definition: DeclTemplate.h:50
void AddTemplateArgument(TemplateArgument TA)
Definition: ODRHash.cpp:131
void clear()
Definition: ODRHash.cpp:170
static bool isWhitelistedDecl(const Decl *D, const CXXRecordDecl *Record)
Definition: ODRHash.cpp:398
One of these records is kept for each identifier that is lexed.
void AddTemplateParameterList(const TemplateParameterList *TPL)
Definition: ODRHash.cpp:161
void AddDecl(const Decl *D)
Definition: ODRHash.cpp:469
void AddTemplateName(TemplateName Name)
Definition: ODRHash.cpp:113
const FunctionProtoType * T
void AddDeclarationName(DeclarationName Name)
Definition: ODRHash.cpp:35
Represents a C++ template name within the type system.
Definition: TemplateName.h:176
void AddType(const Type *T)
Definition: ODRHash.cpp:677
void AddIdentifierInfo(const IdentifierInfo *II)
Definition: ODRHash.cpp:30
Represents a C++ nested name specifier, such as "\::std::vector<int>::".
void AddNestedNameSpecifier(const NestedNameSpecifier *NNS)
Definition: ODRHash.cpp:84
void AddSubDecl(const Decl *D)
Definition: ODRHash.cpp:419
Represents a template argument.
Definition: TemplateBase.h:40
Dataflow Directional Tag Classes.
void AddCXXRecordDecl(const CXXRecordDecl *Record)
Definition: ODRHash.cpp:426
DeclarationName - The name of a declaration.
unsigned CalculateHash()
Definition: ODRHash.cpp:177
Represents a C++ struct/union/class.
Definition: DeclCXX.h:266
void AddStmt(const Stmt *S)
Definition: ODRHash.cpp:25