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 LLVM_CLANG_LIB_CODEGEN_CGVTABLES_H
15 #define LLVM_CLANG_LIB_CODEGEN_CGVTABLES_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 VTableContextBase *VTContext;
36 /// VTableAddressPointsMapTy - Address points for a single vtable.
37 typedef llvm::DenseMap<BaseSubobject, uint64_t> VTableAddressPointsMapTy;
39 typedef std::pair<const CXXRecordDecl *, BaseSubobject> BaseSubobjectPairTy;
40 typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t> SubVTTIndiciesMapTy;
42 /// SubVTTIndicies - Contains indices into the various sub-VTTs.
43 SubVTTIndiciesMapTy SubVTTIndicies;
45 typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t>
46 SecondaryVirtualPointerIndicesMapTy;
48 /// SecondaryVirtualPointerIndices - Contains the secondary virtual pointer
50 SecondaryVirtualPointerIndicesMapTy SecondaryVirtualPointerIndices;
52 /// emitThunk - Emit a single thunk.
53 void emitThunk(GlobalDecl GD, const ThunkInfo &Thunk, bool ForVTable);
55 /// maybeEmitThunkForVTable - Emit the given thunk for the vtable if needed by
57 void maybeEmitThunkForVTable(GlobalDecl GD, const ThunkInfo &Thunk);
60 /// CreateVTableInitializer - Create a vtable initializer for the given record
62 /// \param Components - The vtable components; this is really an array of
64 llvm::Constant *CreateVTableInitializer(
65 const CXXRecordDecl *RD, const VTableComponent *Components,
66 unsigned NumComponents, const VTableLayout::VTableThunkTy *VTableThunks,
67 unsigned NumVTableThunks, llvm::Constant *RTTI);
69 CodeGenVTables(CodeGenModule &CGM);
71 ItaniumVTableContext &getItaniumVTableContext() {
72 return *cast<ItaniumVTableContext>(VTContext);
75 MicrosoftVTableContext &getMicrosoftVTableContext() {
76 return *cast<MicrosoftVTableContext>(VTContext);
79 /// getSubVTTIndex - Return the index of the sub-VTT for the base class of the
80 /// given record decl.
81 uint64_t getSubVTTIndex(const CXXRecordDecl *RD, BaseSubobject Base);
83 /// getSecondaryVirtualPointerIndex - Return the index in the VTT where the
84 /// virtual pointer for the given subobject is located.
85 uint64_t getSecondaryVirtualPointerIndex(const CXXRecordDecl *RD,
88 /// getAddressPoint - Get the address point of the given subobject in the
90 uint64_t getAddressPoint(BaseSubobject Base, const CXXRecordDecl *RD);
92 /// GenerateConstructionVTable - Generate a construction vtable for the given
94 llvm::GlobalVariable *
95 GenerateConstructionVTable(const CXXRecordDecl *RD, const BaseSubobject &Base,
97 llvm::GlobalVariable::LinkageTypes Linkage,
98 VTableAddressPointsMapTy& AddressPoints);
101 /// GetAddrOfVTT - Get the address of the VTT for the given record decl.
102 llvm::GlobalVariable *GetAddrOfVTT(const CXXRecordDecl *RD);
104 /// EmitVTTDefinition - Emit the definition of the given vtable.
105 void EmitVTTDefinition(llvm::GlobalVariable *VTT,
106 llvm::GlobalVariable::LinkageTypes Linkage,
107 const CXXRecordDecl *RD);
109 /// EmitThunks - Emit the associated thunks for the given global decl.
110 void EmitThunks(GlobalDecl GD);
112 /// GenerateClassData - Generate all the class data required to be
113 /// generated upon definition of a KeyFunction. This includes the
114 /// vtable, the RTTI data structure (if RTTI is enabled) and the VTT
115 /// (if the class has virtual bases).
116 void GenerateClassData(const CXXRecordDecl *RD);
118 bool isVTableExternal(const CXXRecordDecl *RD);
121 } // end namespace CodeGen
122 } // end namespace clang