#include "clang/AST/VTableBuilder.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/RecordLayout.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/Support/Format.h"
#include <algorithm>
#include <cstdio>
using namespace clang;
#define DUMP_OVERRIDERS 0
namespace {
struct BaseOffset {
const CXXRecordDecl *DerivedClass;
const CXXRecordDecl *VirtualBase;
CharUnits NonVirtualOffset;
BaseOffset() : DerivedClass(0), VirtualBase(0),
NonVirtualOffset(CharUnits::Zero()) { }
BaseOffset(const CXXRecordDecl *DerivedClass,
const CXXRecordDecl *VirtualBase, CharUnits NonVirtualOffset)
: DerivedClass(DerivedClass), VirtualBase(VirtualBase),
NonVirtualOffset(NonVirtualOffset) { }
bool isEmpty() const { return NonVirtualOffset.isZero() && !VirtualBase; }
};
class FinalOverriders {
public:
struct OverriderInfo {
const CXXMethodDecl *Method;
CharUnits Offset;
OverriderInfo() : Method(0), Offset(CharUnits::Zero()) { }
};
private:
const CXXRecordDecl *MostDerivedClass;
const CharUnits MostDerivedClassOffset;
const CXXRecordDecl *LayoutClass;
ASTContext &Context;
const ASTRecordLayout &MostDerivedClassLayout;
typedef std::pair<const CXXMethodDecl *, CharUnits> MethodBaseOffsetPairTy;
typedef llvm::DenseMap<MethodBaseOffsetPairTy,
OverriderInfo> OverridersMapTy;
OverridersMapTy OverridersMap;
typedef llvm::DenseMap<std::pair<const CXXRecordDecl *, unsigned>,
CharUnits> SubobjectOffsetMapTy;
typedef llvm::DenseMap<const CXXRecordDecl *, unsigned> SubobjectCountMapTy;
void ComputeBaseOffsets(BaseSubobject Base, bool IsVirtual,
CharUnits OffsetInLayoutClass,
SubobjectOffsetMapTy &SubobjectOffsets,
SubobjectOffsetMapTy &SubobjectLayoutClassOffsets,
SubobjectCountMapTy &SubobjectCounts);
typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
void dump(raw_ostream &Out, BaseSubobject Base,
VisitedVirtualBasesSetTy& VisitedVirtualBases);
public:
FinalOverriders(const CXXRecordDecl *MostDerivedClass,
CharUnits MostDerivedClassOffset,
const CXXRecordDecl *LayoutClass);
OverriderInfo getOverrider(const CXXMethodDecl *MD,
CharUnits BaseOffset) const {
assert(OverridersMap.count(std::make_pair(MD, BaseOffset)) &&
"Did not find overrider!");
return OverridersMap.lookup(std::make_pair(MD, BaseOffset));
}
void dump() {
VisitedVirtualBasesSetTy VisitedVirtualBases;
dump(llvm::errs(), BaseSubobject(MostDerivedClass, CharUnits::Zero()),
VisitedVirtualBases);
}
};
#define DUMP_OVERRIDERS 0
FinalOverriders::FinalOverriders(const CXXRecordDecl *MostDerivedClass,
CharUnits MostDerivedClassOffset,
const CXXRecordDecl *LayoutClass)
: MostDerivedClass(MostDerivedClass),
MostDerivedClassOffset(MostDerivedClassOffset), LayoutClass(LayoutClass),
Context(MostDerivedClass->getASTContext()),
MostDerivedClassLayout(Context.getASTRecordLayout(MostDerivedClass)) {
SubobjectOffsetMapTy SubobjectOffsets;
SubobjectOffsetMapTy SubobjectLayoutClassOffsets;
SubobjectCountMapTy SubobjectCounts;
ComputeBaseOffsets(BaseSubobject(MostDerivedClass, CharUnits::Zero()),
false,
MostDerivedClassOffset,
SubobjectOffsets, SubobjectLayoutClassOffsets,
SubobjectCounts);
CXXFinalOverriderMap FinalOverriders;
MostDerivedClass->getFinalOverriders(FinalOverriders);
for (CXXFinalOverriderMap::const_iterator I = FinalOverriders.begin(),
E = FinalOverriders.end(); I != E; ++I) {
const CXXMethodDecl *MD = I->first;
const OverridingMethods& Methods = I->second;
for (OverridingMethods::const_iterator I = Methods.begin(),
E = Methods.end(); I != E; ++I) {
unsigned SubobjectNumber = I->first;
assert(SubobjectOffsets.count(std::make_pair(MD->getParent(),
SubobjectNumber)) &&
"Did not find subobject offset!");
CharUnits BaseOffset = SubobjectOffsets[std::make_pair(MD->getParent(),
SubobjectNumber)];
assert(I->second.size() == 1 && "Final overrider is not unique!");
const UniqueVirtualMethod &Method = I->second.front();
const CXXRecordDecl *OverriderRD = Method.Method->getParent();
assert(SubobjectLayoutClassOffsets.count(
std::make_pair(OverriderRD, Method.Subobject))
&& "Did not find subobject offset!");
CharUnits OverriderOffset =
SubobjectLayoutClassOffsets[std::make_pair(OverriderRD,
Method.Subobject)];
OverriderInfo& Overrider = OverridersMap[std::make_pair(MD, BaseOffset)];
assert(!Overrider.Method && "Overrider should not exist yet!");
Overrider.Offset = OverriderOffset;
Overrider.Method = Method.Method;
}
}
#if DUMP_OVERRIDERS
dump();
#endif
}
static BaseOffset ComputeBaseOffset(ASTContext &Context,
const CXXRecordDecl *DerivedRD,
const CXXBasePath &Path) {
CharUnits NonVirtualOffset = CharUnits::Zero();
unsigned NonVirtualStart = 0;
const CXXRecordDecl *VirtualBase = 0;
for (unsigned I = 0, E = Path.size(); I != E; ++I) {
const CXXBasePathElement &Element = Path[I];
if (Element.Base->isVirtual()) {
NonVirtualStart = I + 1;
QualType VBaseType = Element.Base->getType();
VirtualBase =
cast<CXXRecordDecl>(VBaseType->getAs<RecordType>()->getDecl());
}
}
for (unsigned I = NonVirtualStart, E = Path.size(); I != E; ++I) {
const CXXBasePathElement &Element = Path[I];
const ASTRecordLayout &Layout = Context.getASTRecordLayout(Element.Class);
const RecordType *BaseType = Element.Base->getType()->getAs<RecordType>();
const CXXRecordDecl *Base = cast<CXXRecordDecl>(BaseType->getDecl());
NonVirtualOffset += Layout.getBaseClassOffset(Base);
}
return BaseOffset(DerivedRD, VirtualBase, NonVirtualOffset);
}
static BaseOffset ComputeBaseOffset(ASTContext &Context,
const CXXRecordDecl *BaseRD,
const CXXRecordDecl *DerivedRD) {
CXXBasePaths Paths(false,
true, false);
if (!const_cast<CXXRecordDecl *>(DerivedRD)->
isDerivedFrom(const_cast<CXXRecordDecl *>(BaseRD), Paths)) {
llvm_unreachable("Class must be derived from the passed in base class!");
}
return ComputeBaseOffset(Context, DerivedRD, Paths.front());
}
static BaseOffset
ComputeReturnAdjustmentBaseOffset(ASTContext &Context,
const CXXMethodDecl *DerivedMD,
const CXXMethodDecl *BaseMD) {
const FunctionType *BaseFT = BaseMD->getType()->getAs<FunctionType>();
const FunctionType *DerivedFT = DerivedMD->getType()->getAs<FunctionType>();
CanQualType CanDerivedReturnType =
Context.getCanonicalType(DerivedFT->getResultType());
CanQualType CanBaseReturnType =
Context.getCanonicalType(BaseFT->getResultType());
assert(CanDerivedReturnType->getTypeClass() ==
CanBaseReturnType->getTypeClass() &&
"Types must have same type class!");
if (CanDerivedReturnType == CanBaseReturnType) {
return BaseOffset();
}
if (isa<ReferenceType>(CanDerivedReturnType)) {
CanDerivedReturnType =
CanDerivedReturnType->getAs<ReferenceType>()->getPointeeType();
CanBaseReturnType =
CanBaseReturnType->getAs<ReferenceType>()->getPointeeType();
} else if (isa<PointerType>(CanDerivedReturnType)) {
CanDerivedReturnType =
CanDerivedReturnType->getAs<PointerType>()->getPointeeType();
CanBaseReturnType =
CanBaseReturnType->getAs<PointerType>()->getPointeeType();
} else {
llvm_unreachable("Unexpected return type!");
}
if (CanDerivedReturnType.getUnqualifiedType() ==
CanBaseReturnType.getUnqualifiedType()) {
return BaseOffset();
}
const CXXRecordDecl *DerivedRD =
cast<CXXRecordDecl>(cast<RecordType>(CanDerivedReturnType)->getDecl());
const CXXRecordDecl *BaseRD =
cast<CXXRecordDecl>(cast<RecordType>(CanBaseReturnType)->getDecl());
return ComputeBaseOffset(Context, BaseRD, DerivedRD);
}
void
FinalOverriders::ComputeBaseOffsets(BaseSubobject Base, bool IsVirtual,
CharUnits OffsetInLayoutClass,
SubobjectOffsetMapTy &SubobjectOffsets,
SubobjectOffsetMapTy &SubobjectLayoutClassOffsets,
SubobjectCountMapTy &SubobjectCounts) {
const CXXRecordDecl *RD = Base.getBase();
unsigned SubobjectNumber = 0;
if (!IsVirtual)
SubobjectNumber = ++SubobjectCounts[RD];
assert(!SubobjectOffsets.count(std::make_pair(RD, SubobjectNumber))
&& "Subobject offset already exists!");
assert(!SubobjectLayoutClassOffsets.count(std::make_pair(RD, SubobjectNumber))
&& "Subobject offset already exists!");
SubobjectOffsets[std::make_pair(RD, SubobjectNumber)] = Base.getBaseOffset();
SubobjectLayoutClassOffsets[std::make_pair(RD, SubobjectNumber)] =
OffsetInLayoutClass;
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
CharUnits BaseOffset;
CharUnits BaseOffsetInLayoutClass;
if (I->isVirtual()) {
if (SubobjectOffsets.count(std::make_pair(BaseDecl, 0)))
continue;
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
BaseOffsetInLayoutClass =
LayoutClassLayout.getVBaseClassOffset(BaseDecl);
} else {
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
CharUnits Offset = Layout.getBaseClassOffset(BaseDecl);
BaseOffset = Base.getBaseOffset() + Offset;
BaseOffsetInLayoutClass = OffsetInLayoutClass + Offset;
}
ComputeBaseOffsets(BaseSubobject(BaseDecl, BaseOffset),
I->isVirtual(), BaseOffsetInLayoutClass,
SubobjectOffsets, SubobjectLayoutClassOffsets,
SubobjectCounts);
}
}
void FinalOverriders::dump(raw_ostream &Out, BaseSubobject Base,
VisitedVirtualBasesSetTy &VisitedVirtualBases) {
const CXXRecordDecl *RD = Base.getBase();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
if (!BaseDecl->isPolymorphic())
continue;
CharUnits BaseOffset;
if (I->isVirtual()) {
if (!VisitedVirtualBases.insert(BaseDecl)) {
continue;
}
BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
} else {
BaseOffset = Layout.getBaseClassOffset(BaseDecl) + Base.getBaseOffset();
}
dump(Out, BaseSubobject(BaseDecl, BaseOffset), VisitedVirtualBases);
}
Out << "Final overriders for (" << RD->getQualifiedNameAsString() << ", ";
Out << Base.getBaseOffset().getQuantity() << ")\n";
for (CXXRecordDecl::method_iterator I = RD->method_begin(),
E = RD->method_end(); I != E; ++I) {
const CXXMethodDecl *MD = *I;
if (!MD->isVirtual())
continue;
OverriderInfo Overrider = getOverrider(MD, Base.getBaseOffset());
Out << " " << MD->getQualifiedNameAsString() << " - (";
Out << Overrider.Method->getQualifiedNameAsString();
Out << ", " << ", " << Overrider.Offset.getQuantity() << ')';
BaseOffset Offset;
if (!Overrider.Method->isPure())
Offset = ComputeReturnAdjustmentBaseOffset(Context, Overrider.Method, MD);
if (!Offset.isEmpty()) {
Out << " [ret-adj: ";
if (Offset.VirtualBase)
Out << Offset.VirtualBase->getQualifiedNameAsString() << " vbase, ";
Out << Offset.NonVirtualOffset.getQuantity() << " nv]";
}
Out << "\n";
}
}
struct VCallOffsetMap {
typedef std::pair<const CXXMethodDecl *, CharUnits> MethodAndOffsetPairTy;
SmallVector<MethodAndOffsetPairTy, 16> Offsets;
static bool MethodsCanShareVCallOffset(const CXXMethodDecl *LHS,
const CXXMethodDecl *RHS);
public:
bool AddVCallOffset(const CXXMethodDecl *MD, CharUnits OffsetOffset);
CharUnits getVCallOffsetOffset(const CXXMethodDecl *MD);
bool empty() const { return Offsets.empty(); }
};
static bool HasSameVirtualSignature(const CXXMethodDecl *LHS,
const CXXMethodDecl *RHS) {
const FunctionProtoType *LT =
cast<FunctionProtoType>(LHS->getType().getCanonicalType());
const FunctionProtoType *RT =
cast<FunctionProtoType>(RHS->getType().getCanonicalType());
if (LT == RT) return true;
if (LT->getTypeQuals() != RT->getTypeQuals() ||
LT->getNumArgs() != RT->getNumArgs())
return false;
for (unsigned I = 0, E = LT->getNumArgs(); I != E; ++I)
if (LT->getArgType(I) != RT->getArgType(I))
return false;
return true;
}
bool VCallOffsetMap::MethodsCanShareVCallOffset(const CXXMethodDecl *LHS,
const CXXMethodDecl *RHS) {
assert(LHS->isVirtual() && "LHS must be virtual!");
assert(RHS->isVirtual() && "LHS must be virtual!");
if (isa<CXXDestructorDecl>(LHS))
return isa<CXXDestructorDecl>(RHS);
DeclarationName LHSName = LHS->getDeclName();
DeclarationName RHSName = RHS->getDeclName();
if (LHSName != RHSName)
return false;
return HasSameVirtualSignature(LHS, RHS);
}
bool VCallOffsetMap::AddVCallOffset(const CXXMethodDecl *MD,
CharUnits OffsetOffset) {
for (unsigned I = 0, E = Offsets.size(); I != E; ++I) {
if (MethodsCanShareVCallOffset(Offsets[I].first, MD))
return false;
}
Offsets.push_back(MethodAndOffsetPairTy(MD, OffsetOffset));
return true;
}
CharUnits VCallOffsetMap::getVCallOffsetOffset(const CXXMethodDecl *MD) {
for (unsigned I = 0, E = Offsets.size(); I != E; ++I) {
if (MethodsCanShareVCallOffset(Offsets[I].first, MD))
return Offsets[I].second;
}
llvm_unreachable("Should always find a vcall offset offset!");
}
class VCallAndVBaseOffsetBuilder {
public:
typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits>
VBaseOffsetOffsetsMapTy;
private:
const CXXRecordDecl *MostDerivedClass;
const CXXRecordDecl *LayoutClass;
ASTContext &Context;
typedef SmallVector<VTableComponent, 64> VTableComponentVectorTy;
VTableComponentVectorTy Components;
llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBases;
VCallOffsetMap VCallOffsets;
VBaseOffsetOffsetsMapTy VBaseOffsetOffsets;
const FinalOverriders *Overriders;
void AddVCallAndVBaseOffsets(BaseSubobject Base, bool BaseIsVirtual,
CharUnits RealBaseOffset);
void AddVCallOffsets(BaseSubobject Base, CharUnits VBaseOffset);
void AddVBaseOffsets(const CXXRecordDecl *Base,
CharUnits OffsetInLayoutClass);
CharUnits getCurrentOffsetOffset() const;
public:
VCallAndVBaseOffsetBuilder(const CXXRecordDecl *MostDerivedClass,
const CXXRecordDecl *LayoutClass,
const FinalOverriders *Overriders,
BaseSubobject Base, bool BaseIsVirtual,
CharUnits OffsetInLayoutClass)
: MostDerivedClass(MostDerivedClass), LayoutClass(LayoutClass),
Context(MostDerivedClass->getASTContext()), Overriders(Overriders) {
AddVCallAndVBaseOffsets(Base, BaseIsVirtual, OffsetInLayoutClass);
}
typedef VTableComponentVectorTy::const_reverse_iterator const_iterator;
const_iterator components_begin() const { return Components.rbegin(); }
const_iterator components_end() const { return Components.rend(); }
const VCallOffsetMap &getVCallOffsets() const { return VCallOffsets; }
const VBaseOffsetOffsetsMapTy &getVBaseOffsetOffsets() const {
return VBaseOffsetOffsets;
}
};
void
VCallAndVBaseOffsetBuilder::AddVCallAndVBaseOffsets(BaseSubobject Base,
bool BaseIsVirtual,
CharUnits RealBaseOffset) {
const ASTRecordLayout &Layout = Context.getASTRecordLayout(Base.getBase());
if (const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase()) {
bool PrimaryBaseIsVirtual = Layout.isPrimaryBaseVirtual();
CharUnits PrimaryBaseOffset;
if (PrimaryBaseIsVirtual) {
assert(Layout.getVBaseClassOffset(PrimaryBase).isZero() &&
"Primary vbase should have a zero offset!");
const ASTRecordLayout &MostDerivedClassLayout =
Context.getASTRecordLayout(MostDerivedClass);
PrimaryBaseOffset =
MostDerivedClassLayout.getVBaseClassOffset(PrimaryBase);
} else {
assert(Layout.getBaseClassOffset(PrimaryBase).isZero() &&
"Primary base should have a zero offset!");
PrimaryBaseOffset = Base.getBaseOffset();
}
AddVCallAndVBaseOffsets(
BaseSubobject(PrimaryBase,PrimaryBaseOffset),
PrimaryBaseIsVirtual, RealBaseOffset);
}
AddVBaseOffsets(Base.getBase(), RealBaseOffset);
if (BaseIsVirtual)
AddVCallOffsets(Base, RealBaseOffset);
}
CharUnits VCallAndVBaseOffsetBuilder::getCurrentOffsetOffset() const {
int64_t OffsetIndex = -(int64_t)(3 + Components.size());
CharUnits PointerWidth =
Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
CharUnits OffsetOffset = PointerWidth * OffsetIndex;
return OffsetOffset;
}
void VCallAndVBaseOffsetBuilder::AddVCallOffsets(BaseSubobject Base,
CharUnits VBaseOffset) {
const CXXRecordDecl *RD = Base.getBase();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (PrimaryBase && !Layout.isPrimaryBaseVirtual()) {
assert(Layout.getBaseClassOffset(PrimaryBase).isZero() &&
"Primary base should have a zero offset!");
AddVCallOffsets(BaseSubobject(PrimaryBase, Base.getBaseOffset()),
VBaseOffset);
}
for (CXXRecordDecl::method_iterator I = RD->method_begin(),
E = RD->method_end(); I != E; ++I) {
const CXXMethodDecl *MD = *I;
if (!MD->isVirtual())
continue;
CharUnits OffsetOffset = getCurrentOffsetOffset();
if (!VCallOffsets.AddVCallOffset(MD, OffsetOffset))
continue;
CharUnits Offset = CharUnits::Zero();
if (Overriders) {
FinalOverriders::OverriderInfo Overrider =
Overriders->getOverrider(MD, Base.getBaseOffset());
Offset = Overrider.Offset - VBaseOffset;
}
Components.push_back(
VTableComponent::MakeVCallOffset(Offset));
}
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
if (I->isVirtual())
continue;
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
if (BaseDecl == PrimaryBase)
continue;
CharUnits BaseOffset = Base.getBaseOffset() +
Layout.getBaseClassOffset(BaseDecl);
AddVCallOffsets(BaseSubobject(BaseDecl, BaseOffset),
VBaseOffset);
}
}
void
VCallAndVBaseOffsetBuilder::AddVBaseOffsets(const CXXRecordDecl *RD,
CharUnits OffsetInLayoutClass) {
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
if (I->isVirtual() && VisitedVirtualBases.insert(BaseDecl)) {
CharUnits Offset =
LayoutClassLayout.getVBaseClassOffset(BaseDecl) - OffsetInLayoutClass;
assert(!VBaseOffsetOffsets.count(BaseDecl) &&
"vbase offset offset already exists!");
CharUnits VBaseOffsetOffset = getCurrentOffsetOffset();
VBaseOffsetOffsets.insert(
std::make_pair(BaseDecl, VBaseOffsetOffset));
Components.push_back(
VTableComponent::MakeVBaseOffset(Offset));
}
AddVBaseOffsets(BaseDecl, OffsetInLayoutClass);
}
}
class VTableBuilder {
public:
typedef llvm::SmallSetVector<const CXXRecordDecl *, 8>
PrimaryBasesSetVectorTy;
typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits>
VBaseOffsetOffsetsMapTy;
typedef llvm::DenseMap<BaseSubobject, uint64_t>
AddressPointsMapTy;
private:
VTableContext &VTables;
const CXXRecordDecl *MostDerivedClass;
const CharUnits MostDerivedClassOffset;
bool MostDerivedClassIsVirtual;
const CXXRecordDecl *LayoutClass;
ASTContext &Context;
const FinalOverriders Overriders;
llvm::DenseMap<const CXXRecordDecl *, VCallOffsetMap> VCallOffsetsForVBases;
VBaseOffsetOffsetsMapTy VBaseOffsetOffsets;
SmallVector<VTableComponent, 64> Components;
AddressPointsMapTy AddressPoints;
struct MethodInfo {
const CharUnits BaseOffset;
const CharUnits BaseOffsetInLayoutClass;
const uint64_t VTableIndex;
MethodInfo(CharUnits BaseOffset, CharUnits BaseOffsetInLayoutClass,
uint64_t VTableIndex)
: BaseOffset(BaseOffset),
BaseOffsetInLayoutClass(BaseOffsetInLayoutClass),
VTableIndex(VTableIndex) { }
MethodInfo()
: BaseOffset(CharUnits::Zero()),
BaseOffsetInLayoutClass(CharUnits::Zero()),
VTableIndex(0) { }
};
typedef llvm::DenseMap<const CXXMethodDecl *, MethodInfo> MethodInfoMapTy;
MethodInfoMapTy MethodInfoMap;
typedef llvm::DenseMap<uint64_t, ThunkInfo> VTableThunksMapTy;
VTableThunksMapTy VTableThunks;
typedef SmallVector<ThunkInfo, 1> ThunkInfoVectorTy;
typedef llvm::DenseMap<const CXXMethodDecl *, ThunkInfoVectorTy> ThunksMapTy;
ThunksMapTy Thunks;
void AddThunk(const CXXMethodDecl *MD, const ThunkInfo &Thunk);
void ComputeThisAdjustments();
typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
VisitedVirtualBasesSetTy PrimaryVirtualBases;
ReturnAdjustment ComputeReturnAdjustment(BaseOffset Offset);
BaseOffset ComputeThisAdjustmentBaseOffset(BaseSubobject Base,
BaseSubobject Derived) const;
ThisAdjustment
ComputeThisAdjustment(const CXXMethodDecl *MD,
CharUnits BaseOffsetInLayoutClass,
FinalOverriders::OverriderInfo Overrider);
void AddMethod(const CXXMethodDecl *MD, ReturnAdjustment ReturnAdjustment);
bool IsOverriderUsed(const CXXMethodDecl *Overrider,
CharUnits BaseOffsetInLayoutClass,
const CXXRecordDecl *FirstBaseInPrimaryBaseChain,
CharUnits FirstBaseOffsetInLayoutClass) const;
void AddMethods(BaseSubobject Base, CharUnits BaseOffsetInLayoutClass,
const CXXRecordDecl *FirstBaseInPrimaryBaseChain,
CharUnits FirstBaseOffsetInLayoutClass,
PrimaryBasesSetVectorTy &PrimaryBases);
void LayoutVTable();
void LayoutPrimaryAndSecondaryVTables(BaseSubobject Base,
bool BaseIsMorallyVirtual,
bool BaseIsVirtualInLayoutClass,
CharUnits OffsetInLayoutClass);
void LayoutSecondaryVTables(BaseSubobject Base, bool BaseIsMorallyVirtual,
CharUnits OffsetInLayoutClass);
void DeterminePrimaryVirtualBases(const CXXRecordDecl *RD,
CharUnits OffsetInLayoutClass,
VisitedVirtualBasesSetTy &VBases);
void LayoutVTablesForVirtualBases(const CXXRecordDecl *RD,
VisitedVirtualBasesSetTy &VBases);
bool isBuildingConstructorVTable() const {
return MostDerivedClass != LayoutClass;
}
public:
VTableBuilder(VTableContext &VTables, const CXXRecordDecl *MostDerivedClass,
CharUnits MostDerivedClassOffset,
bool MostDerivedClassIsVirtual, const
CXXRecordDecl *LayoutClass)
: VTables(VTables), MostDerivedClass(MostDerivedClass),
MostDerivedClassOffset(MostDerivedClassOffset),
MostDerivedClassIsVirtual(MostDerivedClassIsVirtual),
LayoutClass(LayoutClass), Context(MostDerivedClass->getASTContext()),
Overriders(MostDerivedClass, MostDerivedClassOffset, LayoutClass) {
LayoutVTable();
if (Context.getLangOpts().DumpVTableLayouts)
dumpLayout(llvm::errs());
}
uint64_t getNumThunks() const {
return Thunks.size();
}
ThunksMapTy::const_iterator thunks_begin() const {
return Thunks.begin();
}
ThunksMapTy::const_iterator thunks_end() const {
return Thunks.end();
}
const VBaseOffsetOffsetsMapTy &getVBaseOffsetOffsets() const {
return VBaseOffsetOffsets;
}
const AddressPointsMapTy &getAddressPoints() const {
return AddressPoints;
}
uint64_t getNumVTableComponents() const {
return Components.size();
}
const VTableComponent *vtable_component_begin() const {
return Components.begin();
}
const VTableComponent *vtable_component_end() const {
return Components.end();
}
AddressPointsMapTy::const_iterator address_points_begin() const {
return AddressPoints.begin();
}
AddressPointsMapTy::const_iterator address_points_end() const {
return AddressPoints.end();
}
VTableThunksMapTy::const_iterator vtable_thunks_begin() const {
return VTableThunks.begin();
}
VTableThunksMapTy::const_iterator vtable_thunks_end() const {
return VTableThunks.end();
}
void dumpLayout(raw_ostream&);
};
void VTableBuilder::AddThunk(const CXXMethodDecl *MD, const ThunkInfo &Thunk) {
assert(!isBuildingConstructorVTable() &&
"Can't add thunks for construction vtable");
SmallVector<ThunkInfo, 1> &ThunksVector = Thunks[MD];
if (std::find(ThunksVector.begin(), ThunksVector.end(), Thunk) !=
ThunksVector.end())
return;
ThunksVector.push_back(Thunk);
}
typedef llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverriddenMethodsSetTy;
static void
ComputeAllOverriddenMethods(const CXXMethodDecl *MD,
OverriddenMethodsSetTy& OverriddenMethods) {
assert(MD->isVirtual() && "Method is not virtual!");
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods(); I != E; ++I) {
const CXXMethodDecl *OverriddenMD = *I;
OverriddenMethods.insert(OverriddenMD);
ComputeAllOverriddenMethods(OverriddenMD, OverriddenMethods);
}
}
void VTableBuilder::ComputeThisAdjustments() {
for (MethodInfoMapTy::const_iterator I = MethodInfoMap.begin(),
E = MethodInfoMap.end(); I != E; ++I) {
const CXXMethodDecl *MD = I->first;
const MethodInfo &MethodInfo = I->second;
uint64_t VTableIndex = MethodInfo.VTableIndex;
if (Components[VTableIndex].getKind() ==
VTableComponent::CK_UnusedFunctionPointer)
continue;
FinalOverriders::OverriderInfo Overrider =
Overriders.getOverrider(MD, MethodInfo.BaseOffset);
if (MethodInfo.BaseOffsetInLayoutClass == Overrider.Offset) {
if (VTableThunks.lookup(VTableIndex).Return.isEmpty())
continue;
}
ThisAdjustment ThisAdjustment =
ComputeThisAdjustment(MD, MethodInfo.BaseOffsetInLayoutClass, Overrider);
if (ThisAdjustment.isEmpty())
continue;
VTableThunks[VTableIndex].This = ThisAdjustment;
if (isa<CXXDestructorDecl>(MD)) {
VTableThunks[VTableIndex + 1].This = ThisAdjustment;
}
}
MethodInfoMap.clear();
if (isBuildingConstructorVTable()) {
return;
}
for (VTableThunksMapTy::const_iterator I = VTableThunks.begin(),
E = VTableThunks.end(); I != E; ++I) {
const VTableComponent &Component = Components[I->first];
const ThunkInfo &Thunk = I->second;
const CXXMethodDecl *MD;
switch (Component.getKind()) {
default:
llvm_unreachable("Unexpected vtable component kind!");
case VTableComponent::CK_FunctionPointer:
MD = Component.getFunctionDecl();
break;
case VTableComponent::CK_CompleteDtorPointer:
MD = Component.getDestructorDecl();
break;
case VTableComponent::CK_DeletingDtorPointer:
continue;
}
if (MD->getParent() == MostDerivedClass)
AddThunk(MD, Thunk);
}
}
ReturnAdjustment VTableBuilder::ComputeReturnAdjustment(BaseOffset Offset) {
ReturnAdjustment Adjustment;
if (!Offset.isEmpty()) {
if (Offset.VirtualBase) {
if (Offset.DerivedClass == MostDerivedClass) {
Adjustment.VBaseOffsetOffset =
VBaseOffsetOffsets.lookup(Offset.VirtualBase).getQuantity();
} else {
Adjustment.VBaseOffsetOffset =
VTables.getVirtualBaseOffsetOffset(Offset.DerivedClass,
Offset.VirtualBase).getQuantity();
}
}
Adjustment.NonVirtual = Offset.NonVirtualOffset.getQuantity();
}
return Adjustment;
}
BaseOffset
VTableBuilder::ComputeThisAdjustmentBaseOffset(BaseSubobject Base,
BaseSubobject Derived) const {
const CXXRecordDecl *BaseRD = Base.getBase();
const CXXRecordDecl *DerivedRD = Derived.getBase();
CXXBasePaths Paths(true,
true, true);
if (!const_cast<CXXRecordDecl *>(DerivedRD)->
isDerivedFrom(const_cast<CXXRecordDecl *>(BaseRD), Paths)) {
llvm_unreachable("Class must be derived from the passed in base class!");
}
for (CXXBasePaths::const_paths_iterator I = Paths.begin(), E = Paths.end();
I != E; ++I) {
BaseOffset Offset = ComputeBaseOffset(Context, DerivedRD, *I);
CharUnits OffsetToBaseSubobject = Offset.NonVirtualOffset;
if (Offset.VirtualBase) {
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
OffsetToBaseSubobject +=
LayoutClassLayout.getVBaseClassOffset(Offset.VirtualBase);
} else {
OffsetToBaseSubobject += Derived.getBaseOffset();
}
if (OffsetToBaseSubobject == Base.getBaseOffset()) {
Offset.NonVirtualOffset = -Offset.NonVirtualOffset;
return Offset;
}
}
return BaseOffset();
}
ThisAdjustment
VTableBuilder::ComputeThisAdjustment(const CXXMethodDecl *MD,
CharUnits BaseOffsetInLayoutClass,
FinalOverriders::OverriderInfo Overrider) {
if (Overrider.Method->isPure())
return ThisAdjustment();
BaseSubobject OverriddenBaseSubobject(MD->getParent(),
BaseOffsetInLayoutClass);
BaseSubobject OverriderBaseSubobject(Overrider.Method->getParent(),
Overrider.Offset);
BaseOffset Offset = ComputeThisAdjustmentBaseOffset(OverriddenBaseSubobject,
OverriderBaseSubobject);
if (Offset.isEmpty())
return ThisAdjustment();
ThisAdjustment Adjustment;
if (Offset.VirtualBase) {
VCallOffsetMap &VCallOffsets = VCallOffsetsForVBases[Offset.VirtualBase];
if (VCallOffsets.empty()) {
VCallAndVBaseOffsetBuilder Builder(MostDerivedClass, MostDerivedClass,
0,
BaseSubobject(Offset.VirtualBase,
CharUnits::Zero()),
true,
CharUnits::Zero());
VCallOffsets = Builder.getVCallOffsets();
}
Adjustment.VCallOffsetOffset =
VCallOffsets.getVCallOffsetOffset(MD).getQuantity();
}
Adjustment.NonVirtual = Offset.NonVirtualOffset.getQuantity();
return Adjustment;
}
void
VTableBuilder::AddMethod(const CXXMethodDecl *MD,
ReturnAdjustment ReturnAdjustment) {
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
assert(ReturnAdjustment.isEmpty() &&
"Destructor can't have return adjustment!");
Components.push_back(VTableComponent::MakeCompleteDtor(DD));
Components.push_back(VTableComponent::MakeDeletingDtor(DD));
} else {
if (!ReturnAdjustment.isEmpty())
VTableThunks[Components.size()].Return = ReturnAdjustment;
Components.push_back(VTableComponent::MakeFunction(MD));
}
}
static bool
OverridesIndirectMethodInBases(const CXXMethodDecl *MD,
VTableBuilder::PrimaryBasesSetVectorTy &Bases) {
if (Bases.count(MD->getParent()))
return true;
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods(); I != E; ++I) {
const CXXMethodDecl *OverriddenMD = *I;
if (OverridesIndirectMethodInBases(OverriddenMD, Bases))
return true;
}
return false;
}
bool
VTableBuilder::IsOverriderUsed(const CXXMethodDecl *Overrider,
CharUnits BaseOffsetInLayoutClass,
const CXXRecordDecl *FirstBaseInPrimaryBaseChain,
CharUnits FirstBaseOffsetInLayoutClass) const {
if (BaseOffsetInLayoutClass == FirstBaseOffsetInLayoutClass)
return true;
if (Overrider->getParent() == FirstBaseInPrimaryBaseChain)
return true;
VTableBuilder::PrimaryBasesSetVectorTy PrimaryBases;
const CXXRecordDecl *RD = FirstBaseInPrimaryBaseChain;
PrimaryBases.insert(RD);
while (true) {
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (!PrimaryBase)
break;
if (Layout.isPrimaryBaseVirtual()) {
assert(Layout.getVBaseClassOffset(PrimaryBase).isZero() &&
"Primary base should always be at offset 0!");
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
if (LayoutClassLayout.getVBaseClassOffset(PrimaryBase) !=
FirstBaseOffsetInLayoutClass) {
break;
}
} else {
assert(Layout.getBaseClassOffset(PrimaryBase).isZero() &&
"Primary base should always be at offset 0!");
}
if (!PrimaryBases.insert(PrimaryBase))
llvm_unreachable("Found a duplicate primary base!");
RD = PrimaryBase;
}
return OverridesIndirectMethodInBases(Overrider, PrimaryBases);
}
static const CXXMethodDecl *
FindNearestOverriddenMethod(const CXXMethodDecl *MD,
VTableBuilder::PrimaryBasesSetVectorTy &Bases) {
OverriddenMethodsSetTy OverriddenMethods;
ComputeAllOverriddenMethods(MD, OverriddenMethods);
for (int I = Bases.size(), E = 0; I != E; --I) {
const CXXRecordDecl *PrimaryBase = Bases[I - 1];
for (OverriddenMethodsSetTy::const_iterator I = OverriddenMethods.begin(),
E = OverriddenMethods.end(); I != E; ++I) {
const CXXMethodDecl *OverriddenMD = *I;
if (OverriddenMD->getParent() == PrimaryBase)
return OverriddenMD;
}
}
return 0;
}
void
VTableBuilder::AddMethods(BaseSubobject Base, CharUnits BaseOffsetInLayoutClass,
const CXXRecordDecl *FirstBaseInPrimaryBaseChain,
CharUnits FirstBaseOffsetInLayoutClass,
PrimaryBasesSetVectorTy &PrimaryBases) {
const CXXRecordDecl *RD = Base.getBase();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
if (const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase()) {
CharUnits PrimaryBaseOffset;
CharUnits PrimaryBaseOffsetInLayoutClass;
if (Layout.isPrimaryBaseVirtual()) {
assert(Layout.getVBaseClassOffset(PrimaryBase).isZero() &&
"Primary vbase should have a zero offset!");
const ASTRecordLayout &MostDerivedClassLayout =
Context.getASTRecordLayout(MostDerivedClass);
PrimaryBaseOffset =
MostDerivedClassLayout.getVBaseClassOffset(PrimaryBase);
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
PrimaryBaseOffsetInLayoutClass =
LayoutClassLayout.getVBaseClassOffset(PrimaryBase);
} else {
assert(Layout.getBaseClassOffset(PrimaryBase).isZero() &&
"Primary base should have a zero offset!");
PrimaryBaseOffset = Base.getBaseOffset();
PrimaryBaseOffsetInLayoutClass = BaseOffsetInLayoutClass;
}
AddMethods(BaseSubobject(PrimaryBase, PrimaryBaseOffset),
PrimaryBaseOffsetInLayoutClass, FirstBaseInPrimaryBaseChain,
FirstBaseOffsetInLayoutClass, PrimaryBases);
if (!PrimaryBases.insert(PrimaryBase))
llvm_unreachable("Found a duplicate primary base!");
}
for (CXXRecordDecl::method_iterator I = RD->method_begin(),
E = RD->method_end(); I != E; ++I) {
const CXXMethodDecl *MD = *I;
if (!MD->isVirtual())
continue;
FinalOverriders::OverriderInfo Overrider =
Overriders.getOverrider(MD, Base.getBaseOffset());
if (const CXXMethodDecl *OverriddenMD =
FindNearestOverriddenMethod(MD, PrimaryBases)) {
if (ComputeReturnAdjustmentBaseOffset(Context, MD,
OverriddenMD).isEmpty()) {
assert(MethodInfoMap.count(OverriddenMD) &&
"Did not find the overridden method!");
MethodInfo &OverriddenMethodInfo = MethodInfoMap[OverriddenMD];
MethodInfo MethodInfo(Base.getBaseOffset(), BaseOffsetInLayoutClass,
OverriddenMethodInfo.VTableIndex);
assert(!MethodInfoMap.count(MD) &&
"Should not have method info for this method yet!");
MethodInfoMap.insert(std::make_pair(MD, MethodInfo));
MethodInfoMap.erase(OverriddenMD);
if (!isBuildingConstructorVTable() && OverriddenMD != MD) {
ThisAdjustment ThisAdjustment =
ComputeThisAdjustment(OverriddenMD, BaseOffsetInLayoutClass,
Overrider);
if (ThisAdjustment.VCallOffsetOffset &&
Overrider.Method->getParent() == MostDerivedClass) {
BaseOffset ReturnAdjustmentOffset =
ComputeReturnAdjustmentBaseOffset(Context, Overrider.Method, MD);
ReturnAdjustment ReturnAdjustment =
ComputeReturnAdjustment(ReturnAdjustmentOffset);
AddThunk(Overrider.Method,
ThunkInfo(ThisAdjustment, ReturnAdjustment));
}
}
continue;
}
}
MethodInfo MethodInfo(Base.getBaseOffset(), BaseOffsetInLayoutClass,
Components.size());
assert(!MethodInfoMap.count(MD) &&
"Should not have method info for this method yet!");
MethodInfoMap.insert(std::make_pair(MD, MethodInfo));
const CXXMethodDecl *OverriderMD = Overrider.Method;
if (!IsOverriderUsed(OverriderMD, BaseOffsetInLayoutClass,
FirstBaseInPrimaryBaseChain,
FirstBaseOffsetInLayoutClass)) {
Components.push_back(VTableComponent::MakeUnusedFunction(OverriderMD));
continue;
}
BaseOffset ReturnAdjustmentOffset;
if (!OverriderMD->isPure()) {
ReturnAdjustmentOffset =
ComputeReturnAdjustmentBaseOffset(Context, OverriderMD, MD);
}
ReturnAdjustment ReturnAdjustment =
ComputeReturnAdjustment(ReturnAdjustmentOffset);
AddMethod(Overrider.Method, ReturnAdjustment);
}
}
void VTableBuilder::LayoutVTable() {
LayoutPrimaryAndSecondaryVTables(BaseSubobject(MostDerivedClass,
CharUnits::Zero()),
false,
MostDerivedClassIsVirtual,
MostDerivedClassOffset);
VisitedVirtualBasesSetTy VBases;
DeterminePrimaryVirtualBases(MostDerivedClass, MostDerivedClassOffset,
VBases);
VBases.clear();
LayoutVTablesForVirtualBases(MostDerivedClass, VBases);
bool IsAppleKext = Context.getLangOpts().AppleKext;
if (IsAppleKext)
Components.push_back(VTableComponent::MakeVCallOffset(CharUnits::Zero()));
}
void
VTableBuilder::LayoutPrimaryAndSecondaryVTables(BaseSubobject Base,
bool BaseIsMorallyVirtual,
bool BaseIsVirtualInLayoutClass,
CharUnits OffsetInLayoutClass) {
assert(Base.getBase()->isDynamicClass() && "class does not have a vtable!");
VCallAndVBaseOffsetBuilder Builder(MostDerivedClass, LayoutClass, &Overriders,
Base, BaseIsVirtualInLayoutClass,
OffsetInLayoutClass);
Components.append(Builder.components_begin(), Builder.components_end());
if (BaseIsVirtualInLayoutClass && !Builder.getVCallOffsets().empty()) {
VCallOffsetMap &VCallOffsets = VCallOffsetsForVBases[Base.getBase()];
if (VCallOffsets.empty())
VCallOffsets = Builder.getVCallOffsets();
}
if (Base.getBase() == MostDerivedClass)
VBaseOffsetOffsets = Builder.getVBaseOffsetOffsets();
CharUnits OffsetToTop = MostDerivedClassOffset - OffsetInLayoutClass;
Components.push_back(
VTableComponent::MakeOffsetToTop(OffsetToTop));
Components.push_back(VTableComponent::MakeRTTI(MostDerivedClass));
uint64_t AddressPoint = Components.size();
PrimaryBasesSetVectorTy PrimaryBases;
AddMethods(Base, OffsetInLayoutClass,
Base.getBase(), OffsetInLayoutClass,
PrimaryBases);
ComputeThisAdjustments();
const CXXRecordDecl *RD = Base.getBase();
while (true) {
AddressPoints.insert(std::make_pair(
BaseSubobject(RD, OffsetInLayoutClass),
AddressPoint));
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (!PrimaryBase)
break;
if (Layout.isPrimaryBaseVirtual()) {
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
if (LayoutClassLayout.getVBaseClassOffset(PrimaryBase) !=
OffsetInLayoutClass) {
break;
}
}
RD = PrimaryBase;
}
LayoutSecondaryVTables(Base, BaseIsMorallyVirtual, OffsetInLayoutClass);
}
void VTableBuilder::LayoutSecondaryVTables(BaseSubobject Base,
bool BaseIsMorallyVirtual,
CharUnits OffsetInLayoutClass) {
const CXXRecordDecl *RD = Base.getBase();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
if (I->isVirtual())
continue;
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
if (!BaseDecl->isDynamicClass())
continue;
if (isBuildingConstructorVTable()) {
if (!BaseIsMorallyVirtual && !BaseDecl->getNumVBases())
continue;
}
CharUnits RelativeBaseOffset = Layout.getBaseClassOffset(BaseDecl);
CharUnits BaseOffset = Base.getBaseOffset() + RelativeBaseOffset;
CharUnits BaseOffsetInLayoutClass =
OffsetInLayoutClass + RelativeBaseOffset;
if (BaseDecl == PrimaryBase) {
LayoutSecondaryVTables(BaseSubobject(BaseDecl, BaseOffset),
BaseIsMorallyVirtual, BaseOffsetInLayoutClass);
continue;
}
LayoutPrimaryAndSecondaryVTables(
BaseSubobject(BaseDecl, BaseOffset),
BaseIsMorallyVirtual,
false,
BaseOffsetInLayoutClass);
}
}
void
VTableBuilder::DeterminePrimaryVirtualBases(const CXXRecordDecl *RD,
CharUnits OffsetInLayoutClass,
VisitedVirtualBasesSetTy &VBases) {
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
if (const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase()) {
if (Layout.isPrimaryBaseVirtual()) {
bool IsPrimaryVirtualBase = true;
if (isBuildingConstructorVTable()) {
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
CharUnits PrimaryBaseOffsetInLayoutClass =
LayoutClassLayout.getVBaseClassOffset(PrimaryBase);
if (PrimaryBaseOffsetInLayoutClass != OffsetInLayoutClass)
IsPrimaryVirtualBase = false;
}
if (IsPrimaryVirtualBase)
PrimaryVirtualBases.insert(PrimaryBase);
}
}
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
CharUnits BaseOffsetInLayoutClass;
if (I->isVirtual()) {
if (!VBases.insert(BaseDecl))
continue;
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
BaseOffsetInLayoutClass =
LayoutClassLayout.getVBaseClassOffset(BaseDecl);
} else {
BaseOffsetInLayoutClass =
OffsetInLayoutClass + Layout.getBaseClassOffset(BaseDecl);
}
DeterminePrimaryVirtualBases(BaseDecl, BaseOffsetInLayoutClass, VBases);
}
}
void
VTableBuilder::LayoutVTablesForVirtualBases(const CXXRecordDecl *RD,
VisitedVirtualBasesSetTy &VBases) {
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
E = RD->bases_end(); I != E; ++I) {
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
if (I->isVirtual() && BaseDecl->isDynamicClass() &&
!PrimaryVirtualBases.count(BaseDecl) && VBases.insert(BaseDecl)) {
const ASTRecordLayout &MostDerivedClassLayout =
Context.getASTRecordLayout(MostDerivedClass);
CharUnits BaseOffset =
MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
const ASTRecordLayout &LayoutClassLayout =
Context.getASTRecordLayout(LayoutClass);
CharUnits BaseOffsetInLayoutClass =
LayoutClassLayout.getVBaseClassOffset(BaseDecl);
LayoutPrimaryAndSecondaryVTables(
BaseSubobject(BaseDecl, BaseOffset),
true,
true,
BaseOffsetInLayoutClass);
}
if (BaseDecl->getNumVBases())
LayoutVTablesForVirtualBases(BaseDecl, VBases);
}
}
void VTableBuilder::dumpLayout(raw_ostream& Out) {
if (isBuildingConstructorVTable()) {
Out << "Construction vtable for ('";
Out << MostDerivedClass->getQualifiedNameAsString() << "', ";
Out << MostDerivedClassOffset.getQuantity() << ") in '";
Out << LayoutClass->getQualifiedNameAsString();
} else {
Out << "Vtable for '";
Out << MostDerivedClass->getQualifiedNameAsString();
}
Out << "' (" << Components.size() << " entries).\n";
std::multimap<uint64_t, BaseSubobject> AddressPointsByIndex;
for (AddressPointsMapTy::const_iterator I = AddressPoints.begin(),
E = AddressPoints.end(); I != E; ++I) {
const BaseSubobject& Base = I->first;
uint64_t Index = I->second;
AddressPointsByIndex.insert(std::make_pair(Index, Base));
}
for (unsigned I = 0, E = Components.size(); I != E; ++I) {
uint64_t Index = I;
Out << llvm::format("%4d | ", I);
const VTableComponent &Component = Components[I];
switch (Component.getKind()) {
case VTableComponent::CK_VCallOffset:
Out << "vcall_offset ("
<< Component.getVCallOffset().getQuantity()
<< ")";
break;
case VTableComponent::CK_VBaseOffset:
Out << "vbase_offset ("
<< Component.getVBaseOffset().getQuantity()
<< ")";
break;
case VTableComponent::CK_OffsetToTop:
Out << "offset_to_top ("
<< Component.getOffsetToTop().getQuantity()
<< ")";
break;
case VTableComponent::CK_RTTI:
Out << Component.getRTTIDecl()->getQualifiedNameAsString() << " RTTI";
break;
case VTableComponent::CK_FunctionPointer: {
const CXXMethodDecl *MD = Component.getFunctionDecl();
std::string Str =
PredefinedExpr::ComputeName(PredefinedExpr::PrettyFunctionNoVirtual,
MD);
Out << Str;
if (MD->isPure())
Out << " [pure]";
ThunkInfo Thunk = VTableThunks.lookup(I);
if (!Thunk.isEmpty()) {
if (!Thunk.Return.isEmpty()) {
Out << "\n [return adjustment: ";
Out << Thunk.Return.NonVirtual << " non-virtual";
if (Thunk.Return.VBaseOffsetOffset) {
Out << ", " << Thunk.Return.VBaseOffsetOffset;
Out << " vbase offset offset";
}
Out << ']';
}
if (!Thunk.This.isEmpty()) {
Out << "\n [this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
if (Thunk.This.VCallOffsetOffset) {
Out << ", " << Thunk.This.VCallOffsetOffset;
Out << " vcall offset offset";
}
Out << ']';
}
}
break;
}
case VTableComponent::CK_CompleteDtorPointer:
case VTableComponent::CK_DeletingDtorPointer: {
bool IsComplete =
Component.getKind() == VTableComponent::CK_CompleteDtorPointer;
const CXXDestructorDecl *DD = Component.getDestructorDecl();
Out << DD->getQualifiedNameAsString();
if (IsComplete)
Out << "() [complete]";
else
Out << "() [deleting]";
if (DD->isPure())
Out << " [pure]";
ThunkInfo Thunk = VTableThunks.lookup(I);
if (!Thunk.isEmpty()) {
if (!Thunk.This.isEmpty()) {
Out << "\n [this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
if (Thunk.This.VCallOffsetOffset) {
Out << ", " << Thunk.This.VCallOffsetOffset;
Out << " vcall offset offset";
}
Out << ']';
}
}
break;
}
case VTableComponent::CK_UnusedFunctionPointer: {
const CXXMethodDecl *MD = Component.getUnusedFunctionDecl();
std::string Str =
PredefinedExpr::ComputeName(PredefinedExpr::PrettyFunctionNoVirtual,
MD);
Out << "[unused] " << Str;
if (MD->isPure())
Out << " [pure]";
}
}
Out << '\n';
uint64_t NextIndex = Index + 1;
if (AddressPointsByIndex.count(NextIndex)) {
if (AddressPointsByIndex.count(NextIndex) == 1) {
const BaseSubobject &Base =
AddressPointsByIndex.find(NextIndex)->second;
Out << " -- (" << Base.getBase()->getQualifiedNameAsString();
Out << ", " << Base.getBaseOffset().getQuantity();
Out << ") vtable address --\n";
} else {
CharUnits BaseOffset =
AddressPointsByIndex.lower_bound(NextIndex)->second.getBaseOffset();
std::set<std::string> ClassNames;
for (std::multimap<uint64_t, BaseSubobject>::const_iterator I =
AddressPointsByIndex.lower_bound(NextIndex), E =
AddressPointsByIndex.upper_bound(NextIndex); I != E; ++I) {
assert(I->second.getBaseOffset() == BaseOffset &&
"Invalid base offset!");
const CXXRecordDecl *RD = I->second.getBase();
ClassNames.insert(RD->getQualifiedNameAsString());
}
for (std::set<std::string>::const_iterator I = ClassNames.begin(),
E = ClassNames.end(); I != E; ++I) {
Out << " -- (" << *I;
Out << ", " << BaseOffset.getQuantity() << ") vtable address --\n";
}
}
}
}
Out << '\n';
if (isBuildingConstructorVTable())
return;
if (MostDerivedClass->getNumVBases()) {
std::map<std::string, CharUnits> ClassNamesAndOffsets;
for (VBaseOffsetOffsetsMapTy::const_iterator I = VBaseOffsetOffsets.begin(),
E = VBaseOffsetOffsets.end(); I != E; ++I) {
std::string ClassName = I->first->getQualifiedNameAsString();
CharUnits OffsetOffset = I->second;
ClassNamesAndOffsets.insert(
std::make_pair(ClassName, OffsetOffset));
}
Out << "Virtual base offset offsets for '";
Out << MostDerivedClass->getQualifiedNameAsString() << "' (";
Out << ClassNamesAndOffsets.size();
Out << (ClassNamesAndOffsets.size() == 1 ? " entry" : " entries") << ").\n";
for (std::map<std::string, CharUnits>::const_iterator I =
ClassNamesAndOffsets.begin(), E = ClassNamesAndOffsets.end();
I != E; ++I)
Out << " " << I->first << " | " << I->second.getQuantity() << '\n';
Out << "\n";
}
if (!Thunks.empty()) {
std::map<std::string, const CXXMethodDecl *> MethodNamesAndDecls;
for (ThunksMapTy::const_iterator I = Thunks.begin(), E = Thunks.end();
I != E; ++I) {
const CXXMethodDecl *MD = I->first;
std::string MethodName =
PredefinedExpr::ComputeName(PredefinedExpr::PrettyFunctionNoVirtual,
MD);
MethodNamesAndDecls.insert(std::make_pair(MethodName, MD));
}
for (std::map<std::string, const CXXMethodDecl *>::const_iterator I =
MethodNamesAndDecls.begin(), E = MethodNamesAndDecls.end();
I != E; ++I) {
const std::string &MethodName = I->first;
const CXXMethodDecl *MD = I->second;
ThunkInfoVectorTy ThunksVector = Thunks[MD];
std::sort(ThunksVector.begin(), ThunksVector.end());
Out << "Thunks for '" << MethodName << "' (" << ThunksVector.size();
Out << (ThunksVector.size() == 1 ? " entry" : " entries") << ").\n";
for (unsigned I = 0, E = ThunksVector.size(); I != E; ++I) {
const ThunkInfo &Thunk = ThunksVector[I];
Out << llvm::format("%4d | ", I);
if (!Thunk.Return.isEmpty()) {
Out << "return adjustment: " << Thunk.This.NonVirtual;
Out << " non-virtual";
if (Thunk.Return.VBaseOffsetOffset) {
Out << ", " << Thunk.Return.VBaseOffsetOffset;
Out << " vbase offset offset";
}
if (!Thunk.This.isEmpty())
Out << "\n ";
}
if (!Thunk.This.isEmpty()) {
Out << "this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
if (Thunk.This.VCallOffsetOffset) {
Out << ", " << Thunk.This.VCallOffsetOffset;
Out << " vcall offset offset";
}
}
Out << '\n';
}
Out << '\n';
}
}
std::map<uint64_t, std::string> IndicesMap;
for (CXXRecordDecl::method_iterator i = MostDerivedClass->method_begin(),
e = MostDerivedClass->method_end(); i != e; ++i) {
const CXXMethodDecl *MD = *i;
if (!MD->isVirtual())
continue;
std::string MethodName =
PredefinedExpr::ComputeName(PredefinedExpr::PrettyFunctionNoVirtual,
MD);
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
IndicesMap[VTables.getMethodVTableIndex(GlobalDecl(DD, Dtor_Complete))] =
MethodName + " [complete]";
IndicesMap[VTables.getMethodVTableIndex(GlobalDecl(DD, Dtor_Deleting))] =
MethodName + " [deleting]";
} else {
IndicesMap[VTables.getMethodVTableIndex(MD)] = MethodName;
}
}
if (!IndicesMap.empty()) {
Out << "VTable indices for '";
Out << MostDerivedClass->getQualifiedNameAsString();
Out << "' (" << IndicesMap.size() << " entries).\n";
for (std::map<uint64_t, std::string>::const_iterator I = IndicesMap.begin(),
E = IndicesMap.end(); I != E; ++I) {
uint64_t VTableIndex = I->first;
const std::string &MethodName = I->second;
Out << llvm::format(" %4" PRIu64 " | ", VTableIndex) << MethodName
<< '\n';
}
}
Out << '\n';
}
}
VTableLayout::VTableLayout(uint64_t NumVTableComponents,
const VTableComponent *VTableComponents,
uint64_t NumVTableThunks,
const VTableThunkTy *VTableThunks,
const AddressPointsMapTy &AddressPoints)
: NumVTableComponents(NumVTableComponents),
VTableComponents(new VTableComponent[NumVTableComponents]),
NumVTableThunks(NumVTableThunks),
VTableThunks(new VTableThunkTy[NumVTableThunks]),
AddressPoints(AddressPoints) {
std::copy(VTableComponents, VTableComponents+NumVTableComponents,
this->VTableComponents.get());
std::copy(VTableThunks, VTableThunks+NumVTableThunks,
this->VTableThunks.get());
}
VTableLayout::~VTableLayout() { }
VTableContext::~VTableContext() {
llvm::DeleteContainerSeconds(VTableLayouts);
}
static void
CollectPrimaryBases(const CXXRecordDecl *RD, ASTContext &Context,
VTableBuilder::PrimaryBasesSetVectorTy &PrimaryBases) {
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (!PrimaryBase)
return;
CollectPrimaryBases(PrimaryBase, Context, PrimaryBases);
if (!PrimaryBases.insert(PrimaryBase))
llvm_unreachable("Found a duplicate primary base!");
}
void VTableContext::ComputeMethodVTableIndices(const CXXRecordDecl *RD) {
int64_t CurrentIndex = 0;
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (PrimaryBase) {
assert(PrimaryBase->isCompleteDefinition() &&
"Should have the definition decl of the primary base!");
CurrentIndex = getNumVirtualFunctionPointers(PrimaryBase);
}
VTableBuilder::PrimaryBasesSetVectorTy PrimaryBases;
CollectPrimaryBases(RD, Context, PrimaryBases);
const CXXDestructorDecl *ImplicitVirtualDtor = 0;
for (CXXRecordDecl::method_iterator i = RD->method_begin(),
e = RD->method_end(); i != e; ++i) {
const CXXMethodDecl *MD = *i;
if (!MD->isVirtual())
continue;
if (const CXXMethodDecl *OverriddenMD =
FindNearestOverriddenMethod(MD, PrimaryBases)) {
if (ComputeReturnAdjustmentBaseOffset(Context, MD,
OverriddenMD).isEmpty()) {
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
const CXXDestructorDecl *OverriddenDD =
cast<CXXDestructorDecl>(OverriddenMD);
MethodVTableIndices[GlobalDecl(DD, Dtor_Complete)] =
getMethodVTableIndex(GlobalDecl(OverriddenDD, Dtor_Complete));
MethodVTableIndices[GlobalDecl(DD, Dtor_Deleting)] =
getMethodVTableIndex(GlobalDecl(OverriddenDD, Dtor_Deleting));
} else {
MethodVTableIndices[MD] = getMethodVTableIndex(OverriddenMD);
}
continue;
}
}
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
if (MD->isImplicit()) {
assert(!ImplicitVirtualDtor &&
"Did already see an implicit virtual dtor!");
ImplicitVirtualDtor = DD;
continue;
}
MethodVTableIndices[GlobalDecl(DD, Dtor_Complete)] = CurrentIndex++;
MethodVTableIndices[GlobalDecl(DD, Dtor_Deleting)] = CurrentIndex++;
} else {
MethodVTableIndices[MD] = CurrentIndex++;
}
}
if (ImplicitVirtualDtor) {
MethodVTableIndices[GlobalDecl(ImplicitVirtualDtor, Dtor_Complete)] =
CurrentIndex++;
MethodVTableIndices[GlobalDecl(ImplicitVirtualDtor, Dtor_Deleting)] =
CurrentIndex++;
}
NumVirtualFunctionPointers[RD] = CurrentIndex;
}
uint64_t VTableContext::getNumVirtualFunctionPointers(const CXXRecordDecl *RD) {
llvm::DenseMap<const CXXRecordDecl *, uint64_t>::iterator I =
NumVirtualFunctionPointers.find(RD);
if (I != NumVirtualFunctionPointers.end())
return I->second;
ComputeMethodVTableIndices(RD);
I = NumVirtualFunctionPointers.find(RD);
assert(I != NumVirtualFunctionPointers.end() && "Did not find entry!");
return I->second;
}
uint64_t VTableContext::getMethodVTableIndex(GlobalDecl GD) {
MethodVTableIndicesTy::iterator I = MethodVTableIndices.find(GD);
if (I != MethodVTableIndices.end())
return I->second;
const CXXRecordDecl *RD = cast<CXXMethodDecl>(GD.getDecl())->getParent();
ComputeMethodVTableIndices(RD);
I = MethodVTableIndices.find(GD);
assert(I != MethodVTableIndices.end() && "Did not find index!");
return I->second;
}
CharUnits
VTableContext::getVirtualBaseOffsetOffset(const CXXRecordDecl *RD,
const CXXRecordDecl *VBase) {
ClassPairTy ClassPair(RD, VBase);
VirtualBaseClassOffsetOffsetsMapTy::iterator I =
VirtualBaseClassOffsetOffsets.find(ClassPair);
if (I != VirtualBaseClassOffsetOffsets.end())
return I->second;
VCallAndVBaseOffsetBuilder Builder(RD, RD, 0,
BaseSubobject(RD, CharUnits::Zero()),
false,
CharUnits::Zero());
for (VCallAndVBaseOffsetBuilder::VBaseOffsetOffsetsMapTy::const_iterator I =
Builder.getVBaseOffsetOffsets().begin(),
E = Builder.getVBaseOffsetOffsets().end(); I != E; ++I) {
ClassPairTy ClassPair(RD, I->first);
VirtualBaseClassOffsetOffsets.insert(
std::make_pair(ClassPair, I->second));
}
I = VirtualBaseClassOffsetOffsets.find(ClassPair);
assert(I != VirtualBaseClassOffsetOffsets.end() && "Did not find index!");
return I->second;
}
static VTableLayout *CreateVTableLayout(const VTableBuilder &Builder) {
SmallVector<VTableLayout::VTableThunkTy, 1>
VTableThunks(Builder.vtable_thunks_begin(), Builder.vtable_thunks_end());
std::sort(VTableThunks.begin(), VTableThunks.end());
return new VTableLayout(Builder.getNumVTableComponents(),
Builder.vtable_component_begin(),
VTableThunks.size(),
VTableThunks.data(),
Builder.getAddressPoints());
}
void VTableContext::ComputeVTableRelatedInformation(const CXXRecordDecl *RD) {
const VTableLayout *&Entry = VTableLayouts[RD];
if (Entry)
return;
VTableBuilder Builder(*this, RD, CharUnits::Zero(),
0, RD);
Entry = CreateVTableLayout(Builder);
Thunks.insert(Builder.thunks_begin(), Builder.thunks_end());
if (!RD->getNumVBases())
return;
const RecordType *VBaseRT =
RD->vbases_begin()->getType()->getAs<RecordType>();
const CXXRecordDecl *VBase = cast<CXXRecordDecl>(VBaseRT->getDecl());
if (VirtualBaseClassOffsetOffsets.count(std::make_pair(RD, VBase)))
return;
for (VTableBuilder::VBaseOffsetOffsetsMapTy::const_iterator I =
Builder.getVBaseOffsetOffsets().begin(),
E = Builder.getVBaseOffsetOffsets().end(); I != E; ++I) {
ClassPairTy ClassPair(RD, I->first);
VirtualBaseClassOffsetOffsets.insert(std::make_pair(ClassPair, I->second));
}
}
VTableLayout *VTableContext::createConstructionVTableLayout(
const CXXRecordDecl *MostDerivedClass,
CharUnits MostDerivedClassOffset,
bool MostDerivedClassIsVirtual,
const CXXRecordDecl *LayoutClass) {
VTableBuilder Builder(*this, MostDerivedClass, MostDerivedClassOffset,
MostDerivedClassIsVirtual, LayoutClass);
return CreateVTableLayout(Builder);
}