bool Diff<VTableComponent>(const VTableComponent &old_element,
const VTableComponent &new_element) {
bool kind_comparison = old_element.kind() != new_element.kind();
bool mangled_name_comparison = old_element.mangled_component_name() !=
new_element.mangled_component_name();
bool value_comparison =
old_element.component_value() != new_element.component_value();
return kind_comparison || mangled_name_comparison || value_comparison;
}
llvm::Constant *
CodeGenVTables::CreateVTableInitializer(const CXXRecordDecl *RD,
const VTableComponent *Components,
unsigned NumComponents,
const VTableLayout::VTableThunkTy *VTableThunks,
unsigned NumVTableThunks) {
SmallVector<llvm::Constant *, 64> Inits;
llvm::Type *Int8PtrTy = CGM.Int8PtrTy;
llvm::Type *PtrDiffTy =
CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
QualType ClassType = CGM.getContext().getTagDeclType(RD);
llvm::Constant *RTTI = CGM.GetAddrOfRTTIDescriptor(ClassType);
unsigned NextVTableThunkIndex = 0;
llvm::Constant *PureVirtualFn = 0, *DeletedVirtualFn = 0;
for (unsigned I = 0; I != NumComponents; ++I) {
VTableComponent Component = Components[I];
llvm::Constant *Init = 0;
switch (Component.getKind()) {
case VTableComponent::CK_VCallOffset:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getVCallOffset().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_VBaseOffset:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getVBaseOffset().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_OffsetToTop:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getOffsetToTop().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_RTTI:
Init = llvm::ConstantExpr::getBitCast(RTTI, Int8PtrTy);
break;
case VTableComponent::CK_FunctionPointer:
case VTableComponent::CK_CompleteDtorPointer:
case VTableComponent::CK_DeletingDtorPointer: {
GlobalDecl GD;
// Get the right global decl.
switch (Component.getKind()) {
default:
llvm_unreachable("Unexpected vtable component kind");
case VTableComponent::CK_FunctionPointer:
GD = Component.getFunctionDecl();
break;
case VTableComponent::CK_CompleteDtorPointer:
GD = GlobalDecl(Component.getDestructorDecl(), Dtor_Complete);
break;
case VTableComponent::CK_DeletingDtorPointer:
GD = GlobalDecl(Component.getDestructorDecl(), Dtor_Deleting);
break;
}
if (cast<CXXMethodDecl>(GD.getDecl())->isPure()) {
// We have a pure virtual member function.
if (!PureVirtualFn) {
llvm::FunctionType *Ty =
llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
StringRef PureCallName = CGM.getCXXABI().GetPureVirtualCallName();
PureVirtualFn = CGM.CreateRuntimeFunction(Ty, PureCallName);
PureVirtualFn = llvm::ConstantExpr::getBitCast(PureVirtualFn,
CGM.Int8PtrTy);
}
Init = PureVirtualFn;
} else if (cast<CXXMethodDecl>(GD.getDecl())->isDeleted()) {
if (!DeletedVirtualFn) {
llvm::FunctionType *Ty =
llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
StringRef DeletedCallName =
CGM.getCXXABI().GetDeletedVirtualCallName();
DeletedVirtualFn = CGM.CreateRuntimeFunction(Ty, DeletedCallName);
DeletedVirtualFn = llvm::ConstantExpr::getBitCast(DeletedVirtualFn,
CGM.Int8PtrTy);
}
Init = DeletedVirtualFn;
} else {
// Check if we should use a thunk.
if (NextVTableThunkIndex < NumVTableThunks &&
VTableThunks[NextVTableThunkIndex].first == I) {
const ThunkInfo &Thunk = VTableThunks[NextVTableThunkIndex].second;
maybeEmitThunkForVTable(GD, Thunk);
Init = CGM.GetAddrOfThunk(GD, Thunk);
NextVTableThunkIndex++;
} else {
llvm::Type *Ty = CGM.getTypes().GetFunctionTypeForVTable(GD);
Init = CGM.GetAddrOfFunction(GD, Ty, /*ForVTable=*/true);
}
Init = llvm::ConstantExpr::getBitCast(Init, Int8PtrTy);
}
break;
}
case VTableComponent::CK_UnusedFunctionPointer:
Init = llvm::ConstantExpr::getNullValue(Int8PtrTy);
break;
};
Inits.push_back(Init);
}
llvm::ArrayType *ArrayType = llvm::ArrayType::get(Int8PtrTy, NumComponents);
return llvm::ConstantArray::get(ArrayType, Inits);
}
llvm::Constant *CodeGenVTables::CreateVTableInitializer(
const CXXRecordDecl *RD, const VTableComponent *Components,
unsigned NumComponents, const VTableLayout::VTableThunkTy *VTableThunks,
unsigned NumVTableThunks, llvm::Constant *RTTI) {
SmallVector<llvm::Constant *, 64> Inits;
llvm::Type *Int8PtrTy = CGM.Int8PtrTy;
llvm::Type *PtrDiffTy =
CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
unsigned NextVTableThunkIndex = 0;
llvm::Constant *PureVirtualFn = nullptr, *DeletedVirtualFn = nullptr;
for (unsigned I = 0; I != NumComponents; ++I) {
VTableComponent Component = Components[I];
llvm::Constant *Init = nullptr;
switch (Component.getKind()) {
case VTableComponent::CK_VCallOffset:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getVCallOffset().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_VBaseOffset:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getVBaseOffset().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_OffsetToTop:
Init = llvm::ConstantInt::get(PtrDiffTy,
Component.getOffsetToTop().getQuantity());
Init = llvm::ConstantExpr::getIntToPtr(Init, Int8PtrTy);
break;
case VTableComponent::CK_RTTI:
Init = llvm::ConstantExpr::getBitCast(RTTI, Int8PtrTy);
break;
case VTableComponent::CK_FunctionPointer:
case VTableComponent::CK_CompleteDtorPointer:
case VTableComponent::CK_DeletingDtorPointer: {
GlobalDecl GD;
// Get the right global decl.
switch (Component.getKind()) {
default:
llvm_unreachable("Unexpected vtable component kind");
case VTableComponent::CK_FunctionPointer:
GD = Component.getFunctionDecl();
break;
case VTableComponent::CK_CompleteDtorPointer:
GD = GlobalDecl(Component.getDestructorDecl(), Dtor_Complete);
break;
case VTableComponent::CK_DeletingDtorPointer:
GD = GlobalDecl(Component.getDestructorDecl(), Dtor_Deleting);
break;
}
if (CGM.getLangOpts().CUDA) {
// Emit NULL for methods we can't codegen on this
// side. Otherwise we'd end up with vtable with unresolved
// references.
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
// OK on device side: functions w/ __device__ attribute
// OK on host side: anything except __device__-only functions.
bool CanEmitMethod = CGM.getLangOpts().CUDAIsDevice
? MD->hasAttr<CUDADeviceAttr>()
: (MD->hasAttr<CUDAHostAttr>() ||
!MD->hasAttr<CUDADeviceAttr>());
if (!CanEmitMethod) {
Init = llvm::ConstantExpr::getNullValue(Int8PtrTy);
break;
}
// Method is acceptable, continue processing as usual.
}
if (cast<CXXMethodDecl>(GD.getDecl())->isPure()) {
// We have a pure virtual member function.
if (!PureVirtualFn) {
llvm::FunctionType *Ty =
llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
StringRef PureCallName = CGM.getCXXABI().GetPureVirtualCallName();
PureVirtualFn = CGM.CreateRuntimeFunction(Ty, PureCallName);
if (auto *F = dyn_cast<llvm::Function>(PureVirtualFn))
F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
PureVirtualFn = llvm::ConstantExpr::getBitCast(PureVirtualFn,
CGM.Int8PtrTy);
}
Init = PureVirtualFn;
} else if (cast<CXXMethodDecl>(GD.getDecl())->isDeleted()) {
if (!DeletedVirtualFn) {
llvm::FunctionType *Ty =
llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
StringRef DeletedCallName =
CGM.getCXXABI().GetDeletedVirtualCallName();
DeletedVirtualFn = CGM.CreateRuntimeFunction(Ty, DeletedCallName);
if (auto *F = dyn_cast<llvm::Function>(DeletedVirtualFn))
F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
DeletedVirtualFn = llvm::ConstantExpr::getBitCast(DeletedVirtualFn,
CGM.Int8PtrTy);
}
Init = DeletedVirtualFn;
} else {
// Check if we should use a thunk.
if (NextVTableThunkIndex < NumVTableThunks &&
VTableThunks[NextVTableThunkIndex].first == I) {
const ThunkInfo &Thunk = VTableThunks[NextVTableThunkIndex].second;
maybeEmitThunkForVTable(GD, Thunk);
Init = CGM.GetAddrOfThunk(GD, Thunk);
NextVTableThunkIndex++;
} else {
llvm::Type *Ty = CGM.getTypes().GetFunctionTypeForVTable(GD);
Init = CGM.GetAddrOfFunction(GD, Ty, /*ForVTable=*/true);
}
Init = llvm::ConstantExpr::getBitCast(Init, Int8PtrTy);
}
break;
}
case VTableComponent::CK_UnusedFunctionPointer:
Init = llvm::ConstantExpr::getNullValue(Int8PtrTy);
break;
};
Inits.push_back(Init);
}
llvm::ArrayType *ArrayType = llvm::ArrayType::get(Int8PtrTy, NumComponents);
return llvm::ConstantArray::get(ArrayType, Inits);
}
