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