1 //===--- CGVTables.h - Emit LLVM Code for C++ vtables -----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code dealing with C++ code generation of virtual tables.
12 //===----------------------------------------------------------------------===//
14 #ifndef CLANG_CODEGEN_CGVTABLE_H
15 #define CLANG_CODEGEN_CGVTABLE_H
17 #include "clang/AST/BaseSubobject.h"
18 #include "clang/AST/CharUnits.h"
19 #include "clang/AST/GlobalDecl.h"
20 #include "clang/AST/VTableBuilder.h"
21 #include "clang/Basic/ABI.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/IR/GlobalVariable.h"
31 class CodeGenVTables {
34 // FIXME: Consider moving ItaniumVTContext and MicrosoftVTContext into
35 // respective CXXABI classes?
36 ItaniumVTableContext ItaniumVTContext;
37 OwningPtr<MicrosoftVTableContext> MicrosoftVTContext;
39 /// VTableAddressPointsMapTy - Address points for a single vtable.
40 typedef llvm::DenseMap<BaseSubobject, uint64_t> VTableAddressPointsMapTy;
42 typedef std::pair<const CXXRecordDecl *, BaseSubobject> BaseSubobjectPairTy;
43 typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t> SubVTTIndiciesMapTy;
45 /// SubVTTIndicies - Contains indices into the various sub-VTTs.
46 SubVTTIndiciesMapTy SubVTTIndicies;
48 typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t>
49 SecondaryVirtualPointerIndicesMapTy;
51 /// SecondaryVirtualPointerIndices - Contains the secondary virtual pointer
53 SecondaryVirtualPointerIndicesMapTy SecondaryVirtualPointerIndices;
55 /// emitThunk - Emit a single thunk.
56 void emitThunk(GlobalDecl GD, const ThunkInfo &Thunk, bool ForVTable);
58 /// maybeEmitThunkForVTable - Emit the given thunk for the vtable if needed by
60 void maybeEmitThunkForVTable(GlobalDecl GD, const ThunkInfo &Thunk);
63 /// CreateVTableInitializer - Create a vtable initializer for the given record
65 /// \param Components - The vtable components; this is really an array of
67 llvm::Constant *CreateVTableInitializer(const CXXRecordDecl *RD,
68 const VTableComponent *Components,
69 unsigned NumComponents,
70 const VTableLayout::VTableThunkTy *VTableThunks,
71 unsigned NumVTableThunks);
73 CodeGenVTables(CodeGenModule &CGM);
75 ItaniumVTableContext &getItaniumVTableContext() { return ItaniumVTContext; }
77 MicrosoftVTableContext &getMicrosoftVTableContext() {
78 return *MicrosoftVTContext.get();
81 /// getSubVTTIndex - Return the index of the sub-VTT for the base class of the
82 /// given record decl.
83 uint64_t getSubVTTIndex(const CXXRecordDecl *RD, BaseSubobject Base);
85 /// getSecondaryVirtualPointerIndex - Return the index in the VTT where the
86 /// virtual pointer for the given subobject is located.
87 uint64_t getSecondaryVirtualPointerIndex(const CXXRecordDecl *RD,
90 /// getAddressPoint - Get the address point of the given subobject in the
92 uint64_t getAddressPoint(BaseSubobject Base, const CXXRecordDecl *RD);
94 /// GenerateConstructionVTable - Generate a construction vtable for the given
96 llvm::GlobalVariable *
97 GenerateConstructionVTable(const CXXRecordDecl *RD, const BaseSubobject &Base,
99 llvm::GlobalVariable::LinkageTypes Linkage,
100 VTableAddressPointsMapTy& AddressPoints);
103 /// GetAddrOfVTable - Get the address of the VTT for the given record decl.
104 llvm::GlobalVariable *GetAddrOfVTT(const CXXRecordDecl *RD);
106 /// EmitVTTDefinition - Emit the definition of the given vtable.
107 void EmitVTTDefinition(llvm::GlobalVariable *VTT,
108 llvm::GlobalVariable::LinkageTypes Linkage,
109 const CXXRecordDecl *RD);
111 /// EmitThunks - Emit the associated thunks for the given global decl.
112 void EmitThunks(GlobalDecl GD);
114 /// GenerateClassData - Generate all the class data required to be
115 /// generated upon definition of a KeyFunction. This includes the
116 /// vtable, the RTTI data structure (if RTTI is enabled) and the VTT
117 /// (if the class has virtual bases).
118 void GenerateClassData(const CXXRecordDecl *RD);
120 bool isVTableExternal(const CXXRecordDecl *RD);
123 } // end namespace CodeGen
124 } // end namespace clang