blob: 828330e5e3c4a3bcc414f20bbdc5f13edf6977c7 [file] [log] [blame]
//===--- CGVTables.h - Emit LLVM Code for C++ vtables -----------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This contains code dealing with C++ code generation of virtual tables.
#include "llvm/ADT/DenseMap.h"
#include "llvm/GlobalVariable.h"
#include "clang/Basic/ABI.h"
#include "clang/AST/BaseSubobject.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/GlobalDecl.h"
#include "clang/AST/VTableBuilder.h"
namespace clang {
class CXXRecordDecl;
namespace CodeGen {
class CodeGenModule;
class CodeGenVTables {
CodeGenModule &CGM;
VTableContext VTContext;
/// VTables - All the vtables which have been defined.
llvm::DenseMap<const CXXRecordDecl *, llvm::GlobalVariable *> VTables;
/// VTableAddressPointsMapTy - Address points for a single vtable.
typedef llvm::DenseMap<BaseSubobject, uint64_t> VTableAddressPointsMapTy;
typedef std::pair<const CXXRecordDecl *, BaseSubobject> BaseSubobjectPairTy;
typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t> SubVTTIndiciesMapTy;
/// SubVTTIndicies - Contains indices into the various sub-VTTs.
SubVTTIndiciesMapTy SubVTTIndicies;
typedef llvm::DenseMap<BaseSubobjectPairTy, uint64_t>
/// SecondaryVirtualPointerIndices - Contains the secondary virtual pointer
/// indices.
SecondaryVirtualPointerIndicesMapTy SecondaryVirtualPointerIndices;
/// EmitThunk - Emit a single thunk.
void EmitThunk(GlobalDecl GD, const ThunkInfo &Thunk,
bool UseAvailableExternallyLinkage);
/// MaybeEmitThunkAvailableExternally - Try to emit the given thunk with
/// available_externally linkage to allow for inlining of thunks.
/// This will be done iff optimizations are enabled and the member function
/// doesn't contain any incomplete types.
void MaybeEmitThunkAvailableExternally(GlobalDecl GD, const ThunkInfo &Thunk);
/// CreateVTableInitializer - Create a vtable initializer for the given record
/// decl.
/// \param Components - The vtable components; this is really an array of
/// VTableComponents.
llvm::Constant *CreateVTableInitializer(const CXXRecordDecl *RD,
const VTableComponent *Components,
unsigned NumComponents,
const VTableLayout::VTableThunkTy *VTableThunks,
unsigned NumVTableThunks);
CodeGenVTables(CodeGenModule &CGM);
VTableContext &getVTableContext() { return VTContext; }
/// \brief True if the VTable of this record must be emitted in the
/// translation unit.
bool ShouldEmitVTableInThisTU(const CXXRecordDecl *RD);
/// needsVTTParameter - Return whether the given global decl needs a VTT
/// parameter, which it does if it's a base constructor or destructor with
/// virtual bases.
static bool needsVTTParameter(GlobalDecl GD);
/// getSubVTTIndex - Return the index of the sub-VTT for the base class of the
/// given record decl.
uint64_t getSubVTTIndex(const CXXRecordDecl *RD, BaseSubobject Base);
/// getSecondaryVirtualPointerIndex - Return the index in the VTT where the
/// virtual pointer for the given subobject is located.
uint64_t getSecondaryVirtualPointerIndex(const CXXRecordDecl *RD,
BaseSubobject Base);
/// getAddressPoint - Get the address point of the given subobject in the
/// class decl.
uint64_t getAddressPoint(BaseSubobject Base, const CXXRecordDecl *RD);
/// GetAddrOfVTable - Get the address of the vtable for the given record decl.
llvm::GlobalVariable *GetAddrOfVTable(const CXXRecordDecl *RD);
/// EmitVTableDefinition - Emit the definition of the given vtable.
void EmitVTableDefinition(llvm::GlobalVariable *VTable,
llvm::GlobalVariable::LinkageTypes Linkage,
const CXXRecordDecl *RD);
/// GenerateConstructionVTable - Generate a construction vtable for the given
/// base subobject.
llvm::GlobalVariable *
GenerateConstructionVTable(const CXXRecordDecl *RD, const BaseSubobject &Base,
bool BaseIsVirtual,
llvm::GlobalVariable::LinkageTypes Linkage,
VTableAddressPointsMapTy& AddressPoints);
/// GetAddrOfVTable - Get the address of the VTT for the given record decl.
llvm::GlobalVariable *GetAddrOfVTT(const CXXRecordDecl *RD);
/// EmitVTTDefinition - Emit the definition of the given vtable.
void EmitVTTDefinition(llvm::GlobalVariable *VTT,
llvm::GlobalVariable::LinkageTypes Linkage,
const CXXRecordDecl *RD);
/// EmitThunks - Emit the associated thunks for the given global decl.
void EmitThunks(GlobalDecl GD);
/// GenerateClassData - Generate all the class data required to be generated
/// upon definition of a KeyFunction. This includes the vtable, the
/// rtti data structure and the VTT.
/// \param Linkage - The desired linkage of the vtable, the RTTI and the VTT.
void GenerateClassData(llvm::GlobalVariable::LinkageTypes Linkage,
const CXXRecordDecl *RD);
} // end namespace CodeGen
} // end namespace clang