clang/lib/AST/CXXABI.h

   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
  19 namespace clang {
  20
  21 class ASTContext;
  22 class CXXConstructorDecl;
  23 class DeclaratorDecl;
  24 class MangleContext;
  25 class MangleNumberingContext;
  26 class MemberPointerType;
  27
  28 /// Implements C++ ABI-specific semantic analysis functions.
  29 class CXXABI {
  30 public:
  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.
  76 CXXABI *CreateItaniumCXXABI(ASTContext &Ctx);
  77 CXXABI *CreateMicrosoftCXXABI(ASTContext &Ctx);
  78 std::unique_ptr<MangleNumberingContext>
  79 createItaniumNumberingContext(MangleContext *);
  80 }
  81
  82 #endif