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[clang] Consolidate the relative vtable layout getters #139315

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[clang] Consolidate the relative vtable layout getters #139315

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22 changes: 1 addition & 21 deletions clang/include/clang/AST/VTableBuilder.h
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Expand Up @@ -395,17 +395,7 @@ class ItaniumVTableContext : public VTableContextBase {
void computeVTableRelatedInformation(const CXXRecordDecl *RD) override;

public:
enum VTableComponentLayout {
/// Components in the vtable are pointers to other structs/functions.
Pointer,

/// Components in the vtable are relative offsets between the vtable and the
/// other structs/functions.
Relative,
};

ItaniumVTableContext(ASTContext &Context,
VTableComponentLayout ComponentLayout = Pointer);
ItaniumVTableContext(ASTContext &Context);
~ItaniumVTableContext() override;

const VTableLayout &getVTableLayout(const CXXRecordDecl *RD) {
Expand Down Expand Up @@ -457,16 +447,6 @@ class ItaniumVTableContext : public VTableContextBase {
static bool classof(const VTableContextBase *VT) {
return !VT->isMicrosoft();
}

VTableComponentLayout getVTableComponentLayout() const {
return ComponentLayout;
}

bool isPointerLayout() const { return ComponentLayout == Pointer; }
bool isRelativeLayout() const { return ComponentLayout == Relative; }

private:
VTableComponentLayout ComponentLayout;
};

/// Holds information about the inheritance path to a virtual base or function
Expand Down
5 changes: 1 addition & 4 deletions clang/lib/AST/ASTContext.cpp
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Expand Up @@ -13068,10 +13068,7 @@ VTableContextBase *ASTContext::getVTableContext() {
if (ABI.isMicrosoft())
VTContext.reset(new MicrosoftVTableContext(*this));
else {
auto ComponentLayout = getLangOpts().RelativeCXXABIVTables
? ItaniumVTableContext::Relative
: ItaniumVTableContext::Pointer;
VTContext.reset(new ItaniumVTableContext(*this, ComponentLayout));
VTContext.reset(new ItaniumVTableContext(*this));
}
}
return VTContext.get();
Expand Down
27 changes: 11 additions & 16 deletions clang/lib/AST/VTableBuilder.cpp
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Expand Up @@ -536,8 +536,6 @@ class VCallAndVBaseOffsetBuilder {
VBaseOffsetOffsetsMapTy;

private:
const ItaniumVTableContext &VTables;

/// MostDerivedClass - The most derived class for which we're building vcall
/// and vbase offsets.
const CXXRecordDecl *MostDerivedClass;
Expand Down Expand Up @@ -586,15 +584,13 @@ class VCallAndVBaseOffsetBuilder {
CharUnits getCurrentOffsetOffset() const;

public:
VCallAndVBaseOffsetBuilder(const ItaniumVTableContext &VTables,
const CXXRecordDecl *MostDerivedClass,
VCallAndVBaseOffsetBuilder(const CXXRecordDecl *MostDerivedClass,
const CXXRecordDecl *LayoutClass,
const FinalOverriders *Overriders,
BaseSubobject Base, bool BaseIsVirtual,
CharUnits OffsetInLayoutClass)
: VTables(VTables), MostDerivedClass(MostDerivedClass),
LayoutClass(LayoutClass), Context(MostDerivedClass->getASTContext()),
Overriders(Overriders) {
: MostDerivedClass(MostDerivedClass), LayoutClass(LayoutClass),
Context(MostDerivedClass->getASTContext()), Overriders(Overriders) {

// Add vcall and vbase offsets.
AddVCallAndVBaseOffsets(Base, BaseIsVirtual, OffsetInLayoutClass);
Expand Down Expand Up @@ -674,7 +670,7 @@ CharUnits VCallAndVBaseOffsetBuilder::getCurrentOffsetOffset() const {
// Under the relative ABI, the offset widths are 32-bit ints instead of
// pointer widths.
CharUnits OffsetWidth = Context.toCharUnitsFromBits(
VTables.isRelativeLayout()
Context.getLangOpts().RelativeCXXABIVTables
? 32
: Context.getTargetInfo().getPointerWidth(LangAS::Default));
CharUnits OffsetOffset = OffsetWidth * OffsetIndex;
Expand Down Expand Up @@ -1317,7 +1313,7 @@ ThisAdjustment ItaniumVTableBuilder::ComputeThisAdjustment(
// We don't have vcall offsets for this virtual base, go ahead and
// build them.
VCallAndVBaseOffsetBuilder Builder(
VTables, MostDerivedClass, MostDerivedClass,
MostDerivedClass, MostDerivedClass,
/*Overriders=*/nullptr,
BaseSubobject(Offset.VirtualBase, CharUnits::Zero()),
/*BaseIsVirtual=*/true,
Expand Down Expand Up @@ -1694,9 +1690,9 @@ void ItaniumVTableBuilder::LayoutPrimaryAndSecondaryVTables(
VTableIndices.push_back(VTableIndex);

// Add vcall and vbase offsets for this vtable.
VCallAndVBaseOffsetBuilder Builder(
VTables, MostDerivedClass, LayoutClass, &Overriders, Base,
BaseIsVirtualInLayoutClass, OffsetInLayoutClass);
VCallAndVBaseOffsetBuilder Builder(MostDerivedClass, LayoutClass, &Overriders,
Base, BaseIsVirtualInLayoutClass,
OffsetInLayoutClass);
Components.append(Builder.components_begin(), Builder.components_end());

// Check if we need to add these vcall offsets.
Expand Down Expand Up @@ -2331,9 +2327,8 @@ bool VTableContextBase::hasVtableSlot(const CXXMethodDecl *MD) {
return MD->isVirtual() && !MD->isImmediateFunction();
}

ItaniumVTableContext::ItaniumVTableContext(
ASTContext &Context, VTableComponentLayout ComponentLayout)
: VTableContextBase(/*MS=*/false), ComponentLayout(ComponentLayout) {}
ItaniumVTableContext::ItaniumVTableContext(ASTContext &Context)
: VTableContextBase(/*MS=*/false) {}

ItaniumVTableContext::~ItaniumVTableContext() {}

Expand Down Expand Up @@ -2362,7 +2357,7 @@ ItaniumVTableContext::getVirtualBaseOffsetOffset(const CXXRecordDecl *RD,
if (I != VirtualBaseClassOffsetOffsets.end())
return I->second;

VCallAndVBaseOffsetBuilder Builder(*this, RD, RD, /*Overriders=*/nullptr,
VCallAndVBaseOffsetBuilder Builder(RD, RD, /*Overriders=*/nullptr,
BaseSubobject(RD, CharUnits::Zero()),
/*BaseIsVirtual=*/false,
/*OffsetInLayoutClass=*/CharUnits::Zero());
Expand Down
4 changes: 2 additions & 2 deletions clang/lib/CodeGen/CGClass.cpp
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Expand Up @@ -254,7 +254,7 @@ ApplyNonVirtualAndVirtualOffset(CodeGenFunction &CGF, Address addr,
if (!nonVirtualOffset.isZero()) {
llvm::Type *OffsetType =
(CGF.CGM.getTarget().getCXXABI().isItaniumFamily() &&
CGF.CGM.getItaniumVTableContext().isRelativeLayout())
CGF.CGM.getLangOpts().RelativeCXXABIVTables)
? CGF.Int32Ty
: CGF.PtrDiffTy;
baseOffset =
Expand Down Expand Up @@ -2937,7 +2937,7 @@ llvm::Value *CodeGenFunction::EmitVTableTypeCheckedLoad(
CGM.CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));
llvm::Value *TypeId = llvm::MetadataAsValue::get(CGM.getLLVMContext(), MD);

auto CheckedLoadIntrinsic = CGM.getVTables().useRelativeLayout()
auto CheckedLoadIntrinsic = CGM.getLangOpts().RelativeCXXABIVTables
? llvm::Intrinsic::type_checked_load_relative
: llvm::Intrinsic::type_checked_load;
llvm::Value *CheckedLoad = Builder.CreateCall(
Expand Down
26 changes: 9 additions & 17 deletions clang/lib/CodeGen/CGVTables.cpp
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Expand Up @@ -704,17 +704,8 @@ void CodeGenVTables::addRelativeComponent(ConstantArrayBuilder &builder,
/*position=*/vtableAddressPoint);
}

static bool UseRelativeLayout(const CodeGenModule &CGM) {
return CGM.getTarget().getCXXABI().isItaniumFamily() &&
CGM.getItaniumVTableContext().isRelativeLayout();
}

bool CodeGenVTables::useRelativeLayout() const {
return UseRelativeLayout(CGM);
}

llvm::Type *CodeGenModule::getVTableComponentType() const {
if (UseRelativeLayout(*this))
if (getLangOpts().RelativeCXXABIVTables)
return Int32Ty;
return GlobalsInt8PtrTy;
}
Expand Down Expand Up @@ -746,8 +737,9 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
bool vtableHasLocalLinkage) {
auto &component = layout.vtable_components()[componentIndex];

bool RelativeCXXABIVTables = CGM.getLangOpts().RelativeCXXABIVTables;
auto addOffsetConstant =
useRelativeLayout() ? AddRelativeLayoutOffset : AddPointerLayoutOffset;
RelativeCXXABIVTables ? AddRelativeLayoutOffset : AddPointerLayoutOffset;

switch (component.getKind()) {
case VTableComponent::CK_VCallOffset:
Expand All @@ -760,7 +752,7 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
return addOffsetConstant(CGM, builder, component.getOffsetToTop());

case VTableComponent::CK_RTTI:
if (useRelativeLayout())
if (RelativeCXXABIVTables)
return addRelativeComponent(builder, rtti, vtableAddressPoint,
vtableHasLocalLinkage,
/*isCompleteDtor=*/false);
Expand Down Expand Up @@ -804,7 +796,7 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
// depending on link order, the comdat groups could resolve to the one
// with the local symbol. As a temporary solution, fill these components
// with zero. We shouldn't be calling these in the first place anyway.
if (useRelativeLayout())
if (RelativeCXXABIVTables)
return llvm::ConstantPointerNull::get(CGM.GlobalsInt8PtrTy);

// For NVPTX devices in OpenMP emit special functon as null pointers,
Expand Down Expand Up @@ -856,7 +848,7 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
GD = getItaniumVTableContext().findOriginalMethod(GD);
}

if (useRelativeLayout()) {
if (RelativeCXXABIVTables) {
return addRelativeComponent(
builder, fnPtr, vtableAddressPoint, vtableHasLocalLinkage,
component.getKind() == VTableComponent::CK_CompleteDtorPointer);
Expand All @@ -879,7 +871,7 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
}

case VTableComponent::CK_UnusedFunctionPointer:
if (useRelativeLayout())
if (RelativeCXXABIVTables)
return builder.add(llvm::ConstantExpr::getNullValue(CGM.Int32Ty));
else
return builder.addNullPointer(CGM.GlobalsInt8PtrTy);
Expand Down Expand Up @@ -943,7 +935,7 @@ llvm::GlobalVariable *CodeGenVTables::GenerateConstructionVTable(
Base.getBase(), Out);
SmallString<256> Name(OutName);

bool UsingRelativeLayout = getItaniumVTableContext().isRelativeLayout();
bool UsingRelativeLayout = CGM.getLangOpts().RelativeCXXABIVTables;
bool VTableAliasExists =
UsingRelativeLayout && CGM.getModule().getNamedAlias(Name);
if (VTableAliasExists) {
Expand Down Expand Up @@ -1022,7 +1014,7 @@ void CodeGenVTables::RemoveHwasanMetadata(llvm::GlobalValue *GV) const {
// the original vtable type.
void CodeGenVTables::GenerateRelativeVTableAlias(llvm::GlobalVariable *VTable,
llvm::StringRef AliasNameRef) {
assert(getItaniumVTableContext().isRelativeLayout() &&
assert(CGM.getLangOpts().RelativeCXXABIVTables &&
"Can only use this if the relative vtable ABI is used");
assert(!VTable->isDSOLocal() && "This should be called only if the vtable is "
"not guaranteed to be dso_local");
Expand Down
3 changes: 0 additions & 3 deletions clang/lib/CodeGen/CGVTables.h
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Expand Up @@ -150,9 +150,6 @@ class CodeGenVTables {

/// Return the type used as components for a vtable.
llvm::Type *getVTableComponentType() const;

/// Return true if the relative vtable layout is used.
bool useRelativeLayout() const;
};

} // end namespace CodeGen
Expand Down
22 changes: 11 additions & 11 deletions clang/lib/CodeGen/ItaniumCXXABI.cpp
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Expand Up @@ -742,7 +742,7 @@ CGCallee ItaniumCXXABI::EmitLoadOfMemberFunctionPointer(
Builder.CreateCall(CGM.getIntrinsic(IID), {VFPAddr, TypeId});
}

if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
VirtualFn = CGF.Builder.CreateCall(
CGM.getIntrinsic(llvm::Intrinsic::load_relative,
{VTableOffset->getType()}),
Expand Down Expand Up @@ -1135,7 +1135,7 @@ llvm::Constant *ItaniumCXXABI::BuildMemberPointer(const CXXMethodDecl *MD,
if (MD->isVirtual()) {
uint64_t Index = CGM.getItaniumVTableContext().getMethodVTableIndex(MD);
uint64_t VTableOffset;
if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
// Multiply by 4-byte relative offsets.
VTableOffset = Index * 4;
} else {
Expand Down Expand Up @@ -1596,7 +1596,7 @@ llvm::Value *ItaniumCXXABI::EmitTypeid(CodeGenFunction &CGF,
llvm::Value *Value = CGF.GetVTablePtr(ThisPtr, CGM.GlobalsInt8PtrTy,
ClassDecl);

if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
// Load the type info.
Value = CGF.Builder.CreateCall(
CGM.getIntrinsic(llvm::Intrinsic::load_relative, {CGM.Int32Ty}),
Expand Down Expand Up @@ -1751,7 +1751,7 @@ llvm::Value *ItaniumCXXABI::emitDynamicCastToVoid(CodeGenFunction &CGF,
auto *ClassDecl =
cast<CXXRecordDecl>(SrcRecordTy->castAs<RecordType>()->getDecl());
llvm::Value *OffsetToTop;
if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
// Get the vtable pointer.
llvm::Value *VTable =
CGF.GetVTablePtr(ThisAddr, CGF.UnqualPtrTy, ClassDecl);
Expand Down Expand Up @@ -1803,7 +1803,7 @@ ItaniumCXXABI::GetVirtualBaseClassOffset(CodeGenFunction &CGF,
"vbase.offset.ptr");

llvm::Value *VBaseOffset;
if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
VBaseOffset = CGF.Builder.CreateAlignedLoad(
CGF.Int32Ty, VBaseOffsetPtr, CharUnits::fromQuantity(4),
"vbase.offset");
Expand Down Expand Up @@ -2051,7 +2051,7 @@ void ItaniumCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
}
}

if (VTContext.isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
CGVT.RemoveHwasanMetadata(VTable);
if (!VTable->isDSOLocal())
CGVT.GenerateRelativeVTableAlias(VTable, VTable->getName());
Expand Down Expand Up @@ -2162,7 +2162,7 @@ llvm::GlobalVariable *ItaniumCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
// them based on the size of the initializer which doesn't make sense as only
// single values are read.
LangAS AS = CGM.GetGlobalVarAddressSpace(nullptr);
unsigned PAlign = CGM.getItaniumVTableContext().isRelativeLayout()
unsigned PAlign = CGM.getLangOpts().RelativeCXXABIVTables
? 32
: CGM.getTarget().getPointerAlign(AS);

Expand Down Expand Up @@ -2202,7 +2202,7 @@ CGCallee ItaniumCXXABI::getVirtualFunctionPointer(CodeGenFunction &CGF,
CGF.EmitTypeMetadataCodeForVCall(MethodDecl->getParent(), VTable, Loc);

llvm::Value *VFuncLoad;
if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
VFuncLoad = CGF.Builder.CreateCall(
CGM.getIntrinsic(llvm::Intrinsic::load_relative, {CGM.Int32Ty}),
{VTable, llvm::ConstantInt::get(CGM.Int32Ty, ByteOffset)});
Expand Down Expand Up @@ -2370,7 +2370,7 @@ static llvm::Value *performTypeAdjustment(CodeGenFunction &CGF,
llvm::Value *Offset;
llvm::Value *OffsetPtr = CGF.Builder.CreateConstInBoundsGEP1_64(
CGF.Int8Ty, VTablePtr, VirtualAdjustment);
if (CGF.CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGF.CGM.getLangOpts().RelativeCXXABIVTables) {
// Load the adjustment offset from the vtable as a 32-bit int.
Offset =
CGF.Builder.CreateAlignedLoad(CGF.Int32Ty, OffsetPtr,
Expand Down Expand Up @@ -3963,7 +3963,7 @@ void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty,
llvm::Constant *VTable = nullptr;

// Check if the alias exists. If it doesn't, then get or create the global.
if (CGM.getItaniumVTableContext().isRelativeLayout())
if (CGM.getLangOpts().RelativeCXXABIVTables)
VTable = CGM.getModule().getNamedAlias(VTableName);
if (!VTable) {
llvm::Type *Ty = llvm::ArrayType::get(CGM.GlobalsInt8PtrTy, 0);
Expand All @@ -3976,7 +3976,7 @@ void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty,
CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());

// The vtable address point is 2.
if (CGM.getItaniumVTableContext().isRelativeLayout()) {
if (CGM.getLangOpts().RelativeCXXABIVTables) {
// The vtable address point is 8 bytes after its start:
// 4 for the offset to top + 4 for the relative offset to rtti.
llvm::Constant *Eight = llvm::ConstantInt::get(CGM.Int32Ty, 8);
Expand Down