1 //===----- CXXABI.h - Interface to C++ ABIs ---------------------*- 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 // This provides an abstract class for C++ AST support. Concrete
11 // subclasses of this implement AST support for specific C++ ABIs.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LIB_AST_CXXABI_H
16 #define LLVM_CLANG_LIB_AST_CXXABI_H
17 
18 #include "clang/AST/Type.h"
19 
20 namespace clang {
21 
22 class ASTContext;
23 class CXXConstructorDecl;
24 class DeclaratorDecl;
25 class Expr;
26 class MemberPointerType;
27 class MangleNumberingContext;
28 
29 /// Implements C++ ABI-specific semantic analysis functions.
30 class CXXABI {
31 public:
32   virtual ~CXXABI();
33 
34   struct MemberPointerInfo {
35     uint64_t Width;
36     unsigned Align;
37     bool HasPadding;
38   };
39 
40   /// Returns the width and alignment of a member pointer in bits, as well as
41   /// whether it has padding.
42   virtual MemberPointerInfo
43   getMemberPointerInfo(const MemberPointerType *MPT) const = 0;
44 
45   /// Returns the default calling convention for C++ methods.
46   virtual CallingConv getDefaultMethodCallConv(bool isVariadic) const = 0;
47 
48   /// Returns whether the given class is nearly empty, with just virtual
49   /// pointers and no data except possibly virtual bases.
50   virtual bool isNearlyEmpty(const CXXRecordDecl *RD) const = 0;
51 
52   /// Returns a new mangling number context for this C++ ABI.
53   virtual std::unique_ptr<MangleNumberingContext>
54   createMangleNumberingContext() const = 0;
55 
56   /// Adds a mapping from class to copy constructor for this C++ ABI.
57   virtual void addCopyConstructorForExceptionObject(CXXRecordDecl *,
58                                                     CXXConstructorDecl *) = 0;
59 
60   /// Retrieves the mapping from class to copy constructor for this C++ ABI.
61   virtual const CXXConstructorDecl *
62   getCopyConstructorForExceptionObject(CXXRecordDecl *) = 0;
63 
64   virtual void addTypedefNameForUnnamedTagDecl(TagDecl *TD,
65                                                TypedefNameDecl *DD) = 0;
66 
67   virtual TypedefNameDecl *
68   getTypedefNameForUnnamedTagDecl(const TagDecl *TD) = 0;
69 
70   virtual void addDeclaratorForUnnamedTagDecl(TagDecl *TD,
71                                               DeclaratorDecl *DD) = 0;
72 
73   virtual DeclaratorDecl *getDeclaratorForUnnamedTagDecl(const TagDecl *TD) = 0;
74 };
75 
76 /// Creates an instance of a C++ ABI class.
77 CXXABI *CreateItaniumCXXABI(ASTContext &Ctx);
78 CXXABI *CreateMicrosoftCXXABI(ASTContext &Ctx);
79 }
80 
81 #endif
82