diff --git a/lib/AST/VTableBuilder.cpp b/lib/AST/VTableBuilder.cpp
index 9c1a7016459e72d55f23f3380d2ea7582959ad6f..49e13559d7fc1d152ac31ec50300168e41a42460 100644
--- a/lib/AST/VTableBuilder.cpp
+++ b/lib/AST/VTableBuilder.cpp
@@ -2574,6 +2574,12 @@ public:
MostDerivedClassLayout(Context.getASTRecordLayout(MostDerivedClass)),
WhichVFPtr(*Which),
Overriders(MostDerivedClass, CharUnits(), MostDerivedClass) {
+ // Only include the RTTI component if we know that we will provide a
+ // definition of the vftable.
+ if (Context.getLangOpts().RTTI &&
+ !MostDerivedClass->hasAttr<DLLImportAttr>())
+ Components.push_back(VTableComponent::MakeRTTI(MostDerivedClass));
+
LayoutVFTable();
if (Context.getLangOpts().DumpVTableLayouts)
@@ -2915,7 +2921,8 @@ void VFTableBuilder::AddMethods(BaseSubobject Base, unsigned BaseDepth,
// it requires return adjustment. Insert the method info for this method.
unsigned VBIndex =
LastVBase ? VTables.getVBTableIndex(MostDerivedClass, LastVBase) : 0;
- MethodInfo MI(VBIndex, Components.size());
+ MethodInfo MI(VBIndex, Context.getLangOpts().RTTI ? Components.size() - 1
+ : Components.size());
assert(!MethodInfoMap.count(MD) &&
"Should not have method info for this method yet!");
diff --git a/lib/CodeGen/CGVTables.cpp b/lib/CodeGen/CGVTables.cpp
index 91e6a18398b205d1cf7c9ae3ec8d7a7b94be921b..0df2c43d11b5ffbc485ec2c831b530634d0876cd 100644
--- a/lib/CodeGen/CGVTables.cpp
+++ b/lib/CodeGen/CGVTables.cpp
@@ -431,12 +431,10 @@ void CodeGenVTables::EmitThunks(GlobalDecl GD)
emitThunk(GD, (*ThunkInfoVector)[I], /*ForVTable=*/false);
}
-llvm::Constant *
-CodeGenVTables::CreateVTableInitializer(const CXXRecordDecl *RD,
- const VTableComponent *Components,
- unsigned NumComponents,
- const VTableLayout::VTableThunkTy *VTableThunks,
- unsigned NumVTableThunks) {
+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;
@@ -444,9 +442,6 @@ CodeGenVTables::CreateVTableInitializer(const CXXRecordDecl *RD,
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 = nullptr, *DeletedVirtualFn = nullptr;
@@ -594,13 +589,14 @@ CodeGenVTables::GenerateConstructionVTable(const CXXRecordDecl *RD,
// V-tables are always unnamed_addr.
VTable->setUnnamedAddr(true);
+ llvm::Constant *RTTI = CGM.GetAddrOfRTTIDescriptor(
+ CGM.getContext().getTagDeclType(Base.getBase()));
+
// Create and set the initializer.
- llvm::Constant *Init =
- CreateVTableInitializer(Base.getBase(),
- VTLayout->vtable_component_begin(),
- VTLayout->getNumVTableComponents(),
- VTLayout->vtable_thunk_begin(),
- VTLayout->getNumVTableThunks());
+ llvm::Constant *Init = CreateVTableInitializer(
+ Base.getBase(), VTLayout->vtable_component_begin(),
+ VTLayout->getNumVTableComponents(), VTLayout->vtable_thunk_begin(),
+ VTLayout->getNumVTableThunks(), RTTI);
VTable->setInitializer(Init);
return VTable;
diff --git a/lib/CodeGen/CGVTables.h b/lib/CodeGen/CGVTables.h
index ba67ed41d3e28820e3ef2a28d0baeead87e3b968..69cf079567e3e168d29b5e9c959adf28caf120b6 100644
--- a/lib/CodeGen/CGVTables.h
+++ b/lib/CodeGen/CGVTables.h
@@ -61,11 +61,10 @@ public:
/// 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);
+ llvm::Constant *CreateVTableInitializer(
+ const CXXRecordDecl *RD, const VTableComponent *Components,
+ unsigned NumComponents, const VTableLayout::VTableThunkTy *VTableThunks,
+ unsigned NumVTableThunks, llvm::Constant *RTTI);
CodeGenVTables(CodeGenModule &CGM);
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index d96b34eee6288a7e4981c6e982cbf3b8a8764476..a4d398a2fa74a06d32d4bd5bfa436537688f4acd 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -750,8 +750,8 @@ public:
/// \brief Gets or a creats a Microsoft TypeDescriptor.
llvm::Constant *getMSTypeDescriptor(QualType Ty);
/// \brief Gets or a creats a Microsoft CompleteObjectLocator.
- llvm::GlobalVariable *getMSCompleteObjectLocator(const CXXRecordDecl *RD,
- const VPtrInfo *Info);
+ llvm::Constant *getMSCompleteObjectLocator(const CXXRecordDecl *RD,
+ const VPtrInfo *Info);
/// Gets the address of a block which requires no captures.
llvm::Constant *GetAddrOfGlobalBlock(const BlockExpr *BE, const char *);
diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp
index 28634d8a70bc93d9e725e6bdf13d0e57856330bb..c33eb62ce2af73cebdd0d69af0e7ca6263076e3d 100644
--- a/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/lib/CodeGen/ItaniumCXXABI.cpp
@@ -1182,11 +1182,13 @@ void ItaniumCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
ItaniumVTableContext &VTContext = CGM.getItaniumVTableContext();
const VTableLayout &VTLayout = VTContext.getVTableLayout(RD);
llvm::GlobalVariable::LinkageTypes Linkage = CGM.getVTableLinkage(RD);
+ llvm::Constant *RTTI =
+ CGM.GetAddrOfRTTIDescriptor(CGM.getContext().getTagDeclType(RD));
// Create and set the initializer.
llvm::Constant *Init = CGVT.CreateVTableInitializer(
RD, VTLayout.vtable_component_begin(), VTLayout.getNumVTableComponents(),
- VTLayout.vtable_thunk_begin(), VTLayout.getNumVTableThunks());
+ VTLayout.vtable_thunk_begin(), VTLayout.getNumVTableThunks(), RTTI);
VTable->setInitializer(Init);
// Set the correct linkage.
diff --git a/lib/CodeGen/MicrosoftCXXABI.cpp b/lib/CodeGen/MicrosoftCXXABI.cpp
index f3c79ef967ad862abbd3c37d9527cb791d6659f6..2e9db03e2655e79a1749ccdaabc34f63e5600d6e 100644
--- a/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -403,9 +403,11 @@ public:
private:
typedef std::pair<const CXXRecordDecl *, CharUnits> VFTableIdTy;
- typedef llvm::DenseMap<VFTableIdTy, llvm::GlobalVariable *> VFTablesMapTy;
+ typedef llvm::DenseMap<VFTableIdTy, llvm::GlobalVariable *> VTablesMapTy;
+ typedef llvm::DenseMap<VFTableIdTy, llvm::GlobalValue *> VFTablesMapTy;
/// \brief All the vftables that have been referenced.
VFTablesMapTy VFTablesMap;
+ VTablesMapTy VTablesMap;
/// \brief This set holds the record decls we've deferred vtable emission for.
llvm::SmallPtrSet<const CXXRecordDecl *, 4> DeferredVFTables;
@@ -1051,26 +1053,22 @@ void MicrosoftCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
const CXXRecordDecl *RD) {
MicrosoftVTableContext &VFTContext = CGM.getMicrosoftVTableContext();
VPtrInfoVector VFPtrs = VFTContext.getVFPtrOffsets(RD);
- llvm::GlobalVariable::LinkageTypes Linkage = CGM.getVTableLinkage(RD);
for (VPtrInfo *Info : VFPtrs) {
llvm::GlobalVariable *VTable = getAddrOfVTable(RD, Info->FullOffsetInMDC);
if (VTable->hasInitializer())
continue;
- if (getContext().getLangOpts().RTTI)
- CGM.getMSCompleteObjectLocator(RD, Info);
+
+ llvm::Constant *RTTI = CGM.getMSCompleteObjectLocator(RD, Info);
const VTableLayout &VTLayout =
VFTContext.getVFTableLayout(RD, Info->FullOffsetInMDC);
llvm::Constant *Init = CGVT.CreateVTableInitializer(
RD, VTLayout.vtable_component_begin(),
VTLayout.getNumVTableComponents(), VTLayout.vtable_thunk_begin(),
- VTLayout.getNumVTableThunks());
- VTable->setInitializer(Init);
+ VTLayout.getNumVTableThunks(), RTTI);
- VTable->setLinkage(Linkage);
-
- CGM.setGlobalVisibility(VTable, RD);
+ VTable->setInitializer(Init);
}
}
@@ -1079,8 +1077,9 @@ llvm::Value *MicrosoftCXXABI::getVTableAddressPointInStructor(
const CXXRecordDecl *NearestVBase, bool &NeedsVirtualOffset) {
NeedsVirtualOffset = (NearestVBase != nullptr);
- llvm::Value *VTableAddressPoint =
- getAddrOfVTable(VTableClass, Base.getBaseOffset());
+ (void)getAddrOfVTable(VTableClass, Base.getBaseOffset());
+ VFTableIdTy ID(VTableClass, Base.getBaseOffset());
+ llvm::GlobalValue *VTableAddressPoint = VFTablesMap[ID];
if (!VTableAddressPoint) {
assert(Base.getBase()->getNumVBases() &&
!CGM.getContext().getASTRecordLayout(Base.getBase()).hasOwnVFPtr());
@@ -1097,9 +1096,11 @@ static void mangleVFTableName(MicrosoftMangleContext &MangleContext,
llvm::Constant *MicrosoftCXXABI::getVTableAddressPointForConstExpr(
BaseSubobject Base, const CXXRecordDecl *VTableClass) {
- llvm::Constant *VTable = getAddrOfVTable(VTableClass, Base.getBaseOffset());
- assert(VTable && "Couldn't find a vftable for the given base?");
- return VTable;
+ (void)getAddrOfVTable(VTableClass, Base.getBaseOffset());
+ VFTableIdTy ID(VTableClass, Base.getBaseOffset());
+ llvm::GlobalValue *VFTable = VFTablesMap[ID];
+ assert(VFTable && "Couldn't find a vftable for the given base?");
+ return VFTable;
}
llvm::GlobalVariable *MicrosoftCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
@@ -1108,9 +1109,9 @@ llvm::GlobalVariable *MicrosoftCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
// shouldn't be used in the given record type. We want to cache this result in
// VFTablesMap, thus a simple zero check is not sufficient.
VFTableIdTy ID(RD, VPtrOffset);
- VFTablesMapTy::iterator I;
+ VTablesMapTy::iterator I;
bool Inserted;
- std::tie(I, Inserted) = VFTablesMap.insert(std::make_pair(ID, nullptr));
+ std::tie(I, Inserted) = VTablesMap.insert(std::make_pair(ID, nullptr));
if (!Inserted)
return I->second;
@@ -1140,21 +1141,73 @@ llvm::GlobalVariable *MicrosoftCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
for (size_t J = 0, F = VFPtrs.size(); J != F; ++J) {
if (VFPtrs[J]->FullOffsetInMDC != VPtrOffset)
continue;
+ SmallString<256> VFTableName;
+ mangleVFTableName(getMangleContext(), RD, VFPtrs[J], VFTableName);
+ StringRef VTableName = VFTableName;
- llvm::ArrayType *ArrayType = llvm::ArrayType::get(
- CGM.Int8PtrTy,
+ uint64_t NumVTableSlots =
VTContext.getVFTableLayout(RD, VFPtrs[J]->FullOffsetInMDC)
- .getNumVTableComponents());
-
- SmallString<256> Name;
- mangleVFTableName(getMangleContext(), RD, VFPtrs[J], Name);
- VTable = CGM.CreateOrReplaceCXXRuntimeVariable(
- Name.str(), ArrayType, llvm::GlobalValue::ExternalLinkage);
- VTable->setUnnamedAddr(true);
- if (RD->hasAttr<DLLImportAttr>())
- VTable->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
- else if (RD->hasAttr<DLLExportAttr>())
- VTable->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
+ .getNumVTableComponents();
+ llvm::GlobalValue::LinkageTypes VTableLinkage =
+ llvm::GlobalValue::ExternalLinkage;
+ llvm::ArrayType *VTableType =
+ llvm::ArrayType::get(CGM.Int8PtrTy, NumVTableSlots);
+ if (getContext().getLangOpts().RTTI) {
+ VTableLinkage = llvm::GlobalValue::PrivateLinkage;
+ VTableName = "";
+ }
+
+ VTable = CGM.getModule().getNamedGlobal(VFTableName);
+ if (!VTable) {
+ llvm::GlobalValue *VFTable = VTable = new llvm::GlobalVariable(
+ CGM.getModule(), VTableType, /*isConstant=*/true, VTableLinkage,
+ /*Initializer=*/nullptr, VTableName);
+ VTable->setUnnamedAddr(true);
+ if (getContext().getLangOpts().RTTI && !RD->hasAttr<DLLImportAttr>()) {
+ llvm::Value *GEPIndices[] = {llvm::ConstantInt::get(CGM.IntTy, 0),
+ llvm::ConstantInt::get(CGM.IntTy, 1)};
+ llvm::Constant *VTableGEP =
+ llvm::ConstantExpr::getInBoundsGetElementPtr(VTable, GEPIndices);
+ VFTable = llvm::GlobalAlias::create(
+ cast<llvm::SequentialType>(VTableGEP->getType())->getElementType(),
+ /*AddressSpace=*/0, llvm::GlobalValue::ExternalLinkage,
+ VFTableName.str(), VTableGEP, &CGM.getModule());
+ } else {
+ VTable->setName(VFTableName.str());
+ }
+
+ VFTable->setUnnamedAddr(true);
+ if (RD->hasAttr<DLLImportAttr>())
+ VFTable->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
+ else if (RD->hasAttr<DLLExportAttr>())
+ VFTable->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
+
+ llvm::GlobalValue::LinkageTypes VFTableLinkage = CGM.getVTableLinkage(RD);
+ if (VFTable != VTable) {
+ if (llvm::GlobalValue::isAvailableExternallyLinkage(VFTableLinkage)) {
+ // AvailableExternally implies that we grabbed the data from another
+ // executable. No need to stick the alias in a Comdat.
+ } else if (llvm::GlobalValue::isLocalLinkage(VFTableLinkage)) {
+ // If it's local, it means that the virtual function table can't be
+ // referenced in another translation unit. No need to stick the alias
+ // in a Comdat.
+ } else if (llvm::GlobalValue::isWeakODRLinkage(VFTableLinkage) ||
+ llvm::GlobalValue::isLinkOnceODRLinkage(VFTableLinkage)) {
+ // The alias is going to be dropped into a Comdat, no need to make it
+ // weak.
+ VFTableLinkage = llvm::GlobalValue::ExternalLinkage;
+ llvm::Comdat *C =
+ CGM.getModule().getOrInsertComdat(VFTable->getName());
+ C->setSelectionKind(llvm::Comdat::Largest);
+ VTable->setComdat(C);
+ } else {
+ llvm_unreachable("unexpected linkage for vftable!");
+ }
+ }
+ VFTable->setLinkage(VFTableLinkage);
+ CGM.setGlobalVisibility(VFTable, RD);
+ VFTablesMap[ID] = VFTable;
+ }
break;
}
diff --git a/lib/CodeGen/MicrosoftRTTI.cpp b/lib/CodeGen/MicrosoftRTTI.cpp
index 14dfa8545f632ec5013ca7b131ceffe36575ecef..51d56e94abe38df5a8140fbf841b1400096f59bd 100644
--- a/lib/CodeGen/MicrosoftRTTI.cpp
+++ b/lib/CodeGen/MicrosoftRTTI.cpp
@@ -505,8 +505,10 @@ llvm::Constant *CodeGenModule::getMSTypeDescriptor(QualType Type) {
Int8PtrTy);
}
-llvm::GlobalVariable *
+llvm::Constant *
CodeGenModule::getMSCompleteObjectLocator(const CXXRecordDecl *RD,
const VPtrInfo *Info) {
+ if (!getLangOpts().RTTI)
+ return llvm::Constant::getNullValue(Int8PtrTy);
return MSRTTIBuilder(*this, RD).getCompleteObjectLocator(Info);
}
diff --git a/test/CodeGenCXX/dllexport.cpp b/test/CodeGenCXX/dllexport.cpp
index 0090d95afb355257d808235dc5e00c561e94dbfe..6634009097cba7b1ddf39c2800f00ed588e8a095 100644
--- a/test/CodeGenCXX/dllexport.cpp
+++ b/test/CodeGenCXX/dllexport.cpp
@@ -24,6 +24,9 @@ struct External { int v; };
#define INSTVAR(var) template int var;
#define INST(func) template void func();
+// The vftable for struct W is comdat largest because we have RTTI.
+// M32-DAG: $"\01??_7W@@6B@" = comdat largest
+
//===----------------------------------------------------------------------===//
// Globals
@@ -518,7 +521,8 @@ struct __declspec(dllexport) W { virtual void foo() {} };
// Copy ctor:
// M32-DAG: define weak_odr dllexport x86_thiscallcc %struct.W* @"\01??0W@@QAE@ABU0@@Z"
// vftable:
-// M32-DAG: @"\01??_7W@@6B@" = weak_odr dllexport unnamed_addr constant [1 x i8*] [i8* bitcast (void (%struct.W*)* @"\01?foo@W@@UAEXXZ" to i8*)]
+// M32-DAG: [[W_VTABLE:@.*]] = private unnamed_addr constant [2 x i8*] [i8* bitcast (%MSRTTICompleteObjectLocator* @"\01??_R4W@@6B@" to i8*), i8* bitcast (void (%struct.W*)* @"\01?foo@W@@UAEXXZ" to i8*)], comdat $"\01??_7W@@6B@"
+// M32-DAG: @"\01??_7W@@6B@" = dllexport unnamed_addr alias getelementptr inbounds ([2 x i8*]* [[W_VTABLE]], i32 0, i32 1), comdat $"\01??_7W@@6B@"
// G32-DAG: @_ZTV1W = weak_odr dllexport unnamed_addr constant [3 x i8*] [i8* null, i8* bitcast ({ i8*, i8* }* @_ZTI1W to i8*), i8* bitcast (void (%struct.W*)* @_ZN1W3fooEv to i8*)]
struct __declspec(dllexport) X : public virtual W {};