--- /dev/null
+//===--- VTTBuilder.h - C++ VTT layout builder --------------------*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code dealing with generation of the layout of virtual table
+// tables (VTT).
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_VTTBUILDER_H
+#define LLVM_CLANG_AST_VTTBUILDER_H
+
+#include "clang/AST/BaseSubobject.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/AST/GlobalDecl.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/Basic/ABI.h"
+#include "llvm/ADT/SetVector.h"
+#include <utility>
+
+namespace clang {
+
+class VTTVTable {
+ llvm::PointerIntPair<const CXXRecordDecl *, 1, bool> BaseAndIsVirtual;
+ CharUnits BaseOffset;
+
+public:
+ VTTVTable() {}
+ VTTVTable(const CXXRecordDecl *Base, CharUnits BaseOffset, bool BaseIsVirtual)
+ : BaseAndIsVirtual(Base, BaseIsVirtual), BaseOffset(BaseOffset) {}
+ VTTVTable(BaseSubobject Base, bool BaseIsVirtual)
+ : BaseAndIsVirtual(Base.getBase(), BaseIsVirtual),
+ BaseOffset(Base.getBaseOffset()) {}
+
+ const CXXRecordDecl *getBase() const {
+ return BaseAndIsVirtual.getPointer();
+ }
+
+ CharUnits getBaseOffset() const {
+ return BaseOffset;
+ }
+
+ bool isVirtual() const {
+ return BaseAndIsVirtual.getInt();
+ }
+
+ BaseSubobject getBaseSubobject() const {
+ return BaseSubobject(getBase(), getBaseOffset());
+ }
+};
+
+struct VTTComponent {
+ uint64_t VTableIndex;
+ BaseSubobject VTableBase;
+
+ VTTComponent() {}
+ VTTComponent(uint64_t VTableIndex, BaseSubobject VTableBase)
+ : VTableIndex(VTableIndex), VTableBase(VTableBase) {}
+};
+
+/// VTT builder - Class for building VTT layout information.
+class VTTBuilder {
+
+ ASTContext &Ctx;
+
+ /// MostDerivedClass - The most derived class for which we're building this
+ /// vtable.
+ const CXXRecordDecl *MostDerivedClass;
+
+ typedef SmallVector<VTTVTable, 64> VTTVTablesVectorTy;
+
+ /// VTTVTables - The VTT vtables.
+ VTTVTablesVectorTy VTTVTables;
+
+ typedef SmallVector<VTTComponent, 64> VTTComponentsVectorTy;
+
+ /// VTTComponents - The VTT components.
+ VTTComponentsVectorTy VTTComponents;
+
+ /// MostDerivedClassLayout - the AST record layout of the most derived class.
+ const ASTRecordLayout &MostDerivedClassLayout;
+
+ typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
+
+ typedef llvm::DenseMap<BaseSubobject, uint64_t> AddressPointsMapTy;
+
+ /// SubVTTIndicies - The sub-VTT indices for the bases of the most derived
+ /// class.
+ llvm::DenseMap<BaseSubobject, uint64_t> SubVTTIndicies;
+
+ /// SecondaryVirtualPointerIndices - The secondary virtual pointer indices of
+ /// all subobjects of the most derived class.
+ llvm::DenseMap<BaseSubobject, uint64_t> SecondaryVirtualPointerIndices;
+
+ /// GenerateDefinition - Whether the VTT builder should generate LLVM IR for
+ /// the VTT.
+ bool GenerateDefinition;
+
+ /// AddVTablePointer - Add a vtable pointer to the VTT currently being built.
+ ///
+ /// \param AddressPoints - If the vtable is a construction vtable, this has
+ /// the address points for it.
+ void AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
+ const CXXRecordDecl *VTableClass);
+
+ /// LayoutSecondaryVTTs - Lay out the secondary VTTs of the given base
+ /// subobject.
+ void LayoutSecondaryVTTs(BaseSubobject Base);
+
+ /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
+ /// for the given base subobject.
+ ///
+ /// \param BaseIsMorallyVirtual whether the base subobject is a virtual base
+ /// or a direct or indirect base of a virtual base.
+ ///
+ /// \param AddressPoints - If the vtable is a construction vtable, this has
+ /// the address points for it.
+ void LayoutSecondaryVirtualPointers(BaseSubobject Base,
+ bool BaseIsMorallyVirtual,
+ uint64_t VTableIndex,
+ const CXXRecordDecl *VTableClass,
+ VisitedVirtualBasesSetTy &VBases);
+
+ /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
+ /// for the given base subobject.
+ ///
+ /// \param AddressPoints - If the vtable is a construction vtable, this has
+ /// the address points for it.
+ void LayoutSecondaryVirtualPointers(BaseSubobject Base,
+ uint64_t VTableIndex);
+
+ /// LayoutVirtualVTTs - Lay out the VTTs for the virtual base classes of the
+ /// given record decl.
+ void LayoutVirtualVTTs(const CXXRecordDecl *RD,
+ VisitedVirtualBasesSetTy &VBases);
+
+ /// LayoutVTT - Will lay out the VTT for the given subobject, including any
+ /// secondary VTTs, secondary virtual pointers and virtual VTTs.
+ void LayoutVTT(BaseSubobject Base, bool BaseIsVirtual);
+
+public:
+ VTTBuilder(ASTContext &Ctx, const CXXRecordDecl *MostDerivedClass,
+ bool GenerateDefinition);
+
+ // getVTTComponents - Returns a reference to the VTT components.
+ const VTTComponentsVectorTy &getVTTComponents() const {
+ return VTTComponents;
+ }
+
+ // getVTTVTables - Returns a reference to the VTT vtables.
+ const VTTVTablesVectorTy &getVTTVTables() const {
+ return VTTVTables;
+ }
+
+ /// getSubVTTIndicies - Returns a reference to the sub-VTT indices.
+ const llvm::DenseMap<BaseSubobject, uint64_t> &getSubVTTIndicies() const {
+ return SubVTTIndicies;
+ }
+
+ /// getSecondaryVirtualPointerIndices - Returns a reference to the secondary
+ /// virtual pointer indices.
+ const llvm::DenseMap<BaseSubobject, uint64_t> &
+ getSecondaryVirtualPointerIndices() const {
+ return SecondaryVirtualPointerIndices;
+ }
+
+};
+
+}
+
+#endif
Type.cpp
TypeLoc.cpp
TypePrinter.cpp
+ VTTBuilder.cpp
)
add_dependencies(clangAST ClangARMNeon ClangAttrClasses ClangAttrList
--- /dev/null
+//===--- VTTBuilder.cpp - C++ VTT layout builder --------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code dealing with generation of the layout of virtual table
+// tables (VTT).
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/VTTBuilder.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
+
+VTTBuilder::VTTBuilder(ASTContext &Ctx,
+ const CXXRecordDecl *MostDerivedClass,
+ bool GenerateDefinition)
+ : Ctx(Ctx), MostDerivedClass(MostDerivedClass),
+ MostDerivedClassLayout(Ctx.getASTRecordLayout(MostDerivedClass)),
+ GenerateDefinition(GenerateDefinition) {
+ // Lay out this VTT.
+ LayoutVTT(BaseSubobject(MostDerivedClass, CharUnits::Zero()),
+ /*BaseIsVirtual=*/false);
+}
+
+void VTTBuilder::AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
+ const CXXRecordDecl *VTableClass) {
+ // Store the vtable pointer index if we're generating the primary VTT.
+ if (VTableClass == MostDerivedClass) {
+ assert(!SecondaryVirtualPointerIndices.count(Base) &&
+ "A virtual pointer index already exists for this base subobject!");
+ SecondaryVirtualPointerIndices[Base] = VTTComponents.size();
+ }
+
+ if (!GenerateDefinition) {
+ VTTComponents.push_back(VTTComponent());
+ return;
+ }
+
+ VTTComponents.push_back(VTTComponent(VTableIndex, Base));
+}
+
+void VTTBuilder::LayoutSecondaryVTTs(BaseSubobject Base) {
+ const CXXRecordDecl *RD = Base.getBase();
+
+ for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+ E = RD->bases_end(); I != E; ++I) {
+
+ // Don't layout virtual bases.
+ if (I->isVirtual())
+ continue;
+
+ const CXXRecordDecl *BaseDecl =
+ cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+
+ const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
+ CharUnits BaseOffset = Base.getBaseOffset() +
+ Layout.getBaseClassOffset(BaseDecl);
+
+ // Layout the VTT for this base.
+ LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/false);
+ }
+}
+
+void
+VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base,
+ bool BaseIsMorallyVirtual,
+ uint64_t VTableIndex,
+ const CXXRecordDecl *VTableClass,
+ VisitedVirtualBasesSetTy &VBases) {
+ const CXXRecordDecl *RD = Base.getBase();
+
+ // We're not interested in bases that don't have virtual bases, and not
+ // morally virtual bases.
+ if (!RD->getNumVBases() && !BaseIsMorallyVirtual)
+ return;
+
+ 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());
+
+ // Itanium C++ ABI 2.6.2:
+ // Secondary virtual pointers are present for all bases with either
+ // virtual bases or virtual function declarations overridden along a
+ // virtual path.
+ //
+ // If the base class is not dynamic, we don't want to add it, nor any
+ // of its base classes.
+ if (!BaseDecl->isDynamicClass())
+ continue;
+
+ bool BaseDeclIsMorallyVirtual = BaseIsMorallyVirtual;
+ bool BaseDeclIsNonVirtualPrimaryBase = false;
+ CharUnits BaseOffset;
+ if (I->isVirtual()) {
+ // Ignore virtual bases that we've already visited.
+ if (!VBases.insert(BaseDecl))
+ continue;
+
+ BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
+ BaseDeclIsMorallyVirtual = true;
+ } else {
+ const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
+
+ BaseOffset = Base.getBaseOffset() +
+ Layout.getBaseClassOffset(BaseDecl);
+
+ if (!Layout.isPrimaryBaseVirtual() &&
+ Layout.getPrimaryBase() == BaseDecl)
+ BaseDeclIsNonVirtualPrimaryBase = true;
+ }
+
+ // Itanium C++ ABI 2.6.2:
+ // Secondary virtual pointers: for each base class X which (a) has virtual
+ // bases or is reachable along a virtual path from D, and (b) is not a
+ // non-virtual primary base, the address of the virtual table for X-in-D
+ // or an appropriate construction virtual table.
+ if (!BaseDeclIsNonVirtualPrimaryBase &&
+ (BaseDecl->getNumVBases() || BaseDeclIsMorallyVirtual)) {
+ // Add the vtable pointer.
+ AddVTablePointer(BaseSubobject(BaseDecl, BaseOffset), VTableIndex,
+ VTableClass);
+ }
+
+ // And lay out the secondary virtual pointers for the base class.
+ LayoutSecondaryVirtualPointers(BaseSubobject(BaseDecl, BaseOffset),
+ BaseDeclIsMorallyVirtual, VTableIndex,
+ VTableClass, VBases);
+ }
+}
+
+void
+VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base,
+ uint64_t VTableIndex) {
+ VisitedVirtualBasesSetTy VBases;
+ LayoutSecondaryVirtualPointers(Base, /*BaseIsMorallyVirtual=*/false,
+ VTableIndex, Base.getBase(), VBases);
+}
+
+void VTTBuilder::LayoutVirtualVTTs(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());
+
+ // Check if this is a virtual base.
+ if (I->isVirtual()) {
+ // Check if we've seen this base before.
+ if (!VBases.insert(BaseDecl))
+ continue;
+
+ CharUnits BaseOffset =
+ MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
+
+ LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/true);
+ }
+
+ // We only need to layout virtual VTTs for this base if it actually has
+ // virtual bases.
+ if (BaseDecl->getNumVBases())
+ LayoutVirtualVTTs(BaseDecl, VBases);
+ }
+}
+
+void VTTBuilder::LayoutVTT(BaseSubobject Base, bool BaseIsVirtual) {
+ const CXXRecordDecl *RD = Base.getBase();
+
+ // Itanium C++ ABI 2.6.2:
+ // An array of virtual table addresses, called the VTT, is declared for
+ // each class type that has indirect or direct virtual base classes.
+ if (RD->getNumVBases() == 0)
+ return;
+
+ bool IsPrimaryVTT = Base.getBase() == MostDerivedClass;
+
+ if (!IsPrimaryVTT) {
+ // Remember the sub-VTT index.
+ SubVTTIndicies[Base] = VTTComponents.size();
+ }
+
+ uint64_t VTableIndex = VTTVTables.size();
+ VTTVTables.push_back(VTTVTable(Base, BaseIsVirtual));
+
+ // Add the primary vtable pointer.
+ AddVTablePointer(Base, VTableIndex, RD);
+
+ // Add the secondary VTTs.
+ LayoutSecondaryVTTs(Base);
+
+ // Add the secondary virtual pointers.
+ LayoutSecondaryVirtualPointers(Base, VTableIndex);
+
+ // If this is the primary VTT, we want to lay out virtual VTTs as well.
+ if (IsPrimaryVTT) {
+ VisitedVirtualBasesSetTy VBases;
+ LayoutVirtualVTTs(Base.getBase(), VBases);
+ }
+}
#include "CodeGenModule.h"
#include "CGCXXABI.h"
#include "clang/AST/RecordLayout.h"
+#include "clang/AST/VTTBuilder.h"
using namespace clang;
using namespace CodeGen;
#define D1(x)
-namespace {
-
-class VTTVTable {
- llvm::PointerIntPair<const CXXRecordDecl *, 1, bool> BaseAndIsVirtual;
- CharUnits BaseOffset;
-
-public:
- VTTVTable() {}
- VTTVTable(const CXXRecordDecl *Base, CharUnits BaseOffset, bool BaseIsVirtual)
- : BaseAndIsVirtual(Base, BaseIsVirtual), BaseOffset(BaseOffset) {}
- VTTVTable(BaseSubobject Base, bool BaseIsVirtual)
- : BaseAndIsVirtual(Base.getBase(), BaseIsVirtual),
- BaseOffset(Base.getBaseOffset()) {}
-
- const CXXRecordDecl *getBase() const {
- return BaseAndIsVirtual.getPointer();
- }
-
- CharUnits getBaseOffset() const {
- return BaseOffset;
- }
-
- bool isVirtual() const {
- return BaseAndIsVirtual.getInt();
- }
-
- BaseSubobject getBaseSubobject() const {
- return BaseSubobject(getBase(), getBaseOffset());
- }
-};
-
-struct VTTComponent {
- uint64_t VTableIndex;
- BaseSubobject VTableBase;
-
- VTTComponent() {}
- VTTComponent(uint64_t VTableIndex, BaseSubobject VTableBase)
- : VTableIndex(VTableIndex), VTableBase(VTableBase) {}
-};
-
-/// VTT builder - Class for building VTT layout information.
-class VTTBuilder {
-
- ASTContext &Ctx;
-
- /// MostDerivedClass - The most derived class for which we're building this
- /// vtable.
- const CXXRecordDecl *MostDerivedClass;
-
- typedef SmallVector<VTTVTable, 64> VTTVTablesVectorTy;
-
- /// VTTVTables - The VTT vtables.
- VTTVTablesVectorTy VTTVTables;
-
- typedef SmallVector<VTTComponent, 64> VTTComponentsVectorTy;
-
- /// VTTComponents - The VTT components.
- VTTComponentsVectorTy VTTComponents;
-
- /// MostDerivedClassLayout - the AST record layout of the most derived class.
- const ASTRecordLayout &MostDerivedClassLayout;
-
- typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
-
- typedef llvm::DenseMap<BaseSubobject, uint64_t> AddressPointsMapTy;
-
- /// SubVTTIndicies - The sub-VTT indices for the bases of the most derived
- /// class.
- llvm::DenseMap<BaseSubobject, uint64_t> SubVTTIndicies;
-
- /// SecondaryVirtualPointerIndices - The secondary virtual pointer indices of
- /// all subobjects of the most derived class.
- llvm::DenseMap<BaseSubobject, uint64_t> SecondaryVirtualPointerIndices;
-
- /// GenerateDefinition - Whether the VTT builder should generate LLVM IR for
- /// the VTT.
- bool GenerateDefinition;
-
- /// AddVTablePointer - Add a vtable pointer to the VTT currently being built.
- ///
- /// \param AddressPoints - If the vtable is a construction vtable, this has
- /// the address points for it.
- void AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
- const CXXRecordDecl *VTableClass);
-
- /// LayoutSecondaryVTTs - Lay out the secondary VTTs of the given base
- /// subobject.
- void LayoutSecondaryVTTs(BaseSubobject Base);
-
- /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
- /// for the given base subobject.
- ///
- /// \param BaseIsMorallyVirtual whether the base subobject is a virtual base
- /// or a direct or indirect base of a virtual base.
- ///
- /// \param AddressPoints - If the vtable is a construction vtable, this has
- /// the address points for it.
- void LayoutSecondaryVirtualPointers(BaseSubobject Base,
- bool BaseIsMorallyVirtual,
- uint64_t VTableIndex,
- const CXXRecordDecl *VTableClass,
- VisitedVirtualBasesSetTy &VBases);
-
- /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
- /// for the given base subobject.
- ///
- /// \param AddressPoints - If the vtable is a construction vtable, this has
- /// the address points for it.
- void LayoutSecondaryVirtualPointers(BaseSubobject Base,
- uint64_t VTableIndex);
-
- /// LayoutVirtualVTTs - Lay out the VTTs for the virtual base classes of the
- /// given record decl.
- void LayoutVirtualVTTs(const CXXRecordDecl *RD,
- VisitedVirtualBasesSetTy &VBases);
-
- /// LayoutVTT - Will lay out the VTT for the given subobject, including any
- /// secondary VTTs, secondary virtual pointers and virtual VTTs.
- void LayoutVTT(BaseSubobject Base, bool BaseIsVirtual);
-
-public:
- VTTBuilder(ASTContext &Ctx, const CXXRecordDecl *MostDerivedClass,
- bool GenerateDefinition);
-
- // getVTTComponents - Returns a reference to the VTT components.
- const VTTComponentsVectorTy &getVTTComponents() const {
- return VTTComponents;
- }
-
- // getVTTVTables - Returns a reference to the VTT vtables.
- const VTTVTablesVectorTy &getVTTVTables() const {
- return VTTVTables;
- }
-
- /// getSubVTTIndicies - Returns a reference to the sub-VTT indices.
- const llvm::DenseMap<BaseSubobject, uint64_t> &getSubVTTIndicies() const {
- return SubVTTIndicies;
- }
-
- /// getSecondaryVirtualPointerIndices - Returns a reference to the secondary
- /// virtual pointer indices.
- const llvm::DenseMap<BaseSubobject, uint64_t> &
- getSecondaryVirtualPointerIndices() const {
- return SecondaryVirtualPointerIndices;
- }
-
-};
-
-VTTBuilder::VTTBuilder(ASTContext &Ctx,
- const CXXRecordDecl *MostDerivedClass,
- bool GenerateDefinition)
- : Ctx(Ctx), MostDerivedClass(MostDerivedClass),
- MostDerivedClassLayout(Ctx.getASTRecordLayout(MostDerivedClass)),
- GenerateDefinition(GenerateDefinition) {
- // Lay out this VTT.
- LayoutVTT(BaseSubobject(MostDerivedClass, CharUnits::Zero()),
- /*BaseIsVirtual=*/false);
-}
-
llvm::Constant *GetAddrOfVTTVTable(CodeGenVTables &CGVT,
const CXXRecordDecl *MostDerivedClass,
const VTTVTable &VTable,
AddressPoints);
}
-void VTTBuilder::AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
- const CXXRecordDecl *VTableClass) {
- // Store the vtable pointer index if we're generating the primary VTT.
- if (VTableClass == MostDerivedClass) {
- assert(!SecondaryVirtualPointerIndices.count(Base) &&
- "A virtual pointer index already exists for this base subobject!");
- SecondaryVirtualPointerIndices[Base] = VTTComponents.size();
- }
-
- if (!GenerateDefinition) {
- VTTComponents.push_back(VTTComponent());
- return;
- }
-
- VTTComponents.push_back(VTTComponent(VTableIndex, Base));
-}
-
-void VTTBuilder::LayoutSecondaryVTTs(BaseSubobject Base) {
- const CXXRecordDecl *RD = Base.getBase();
-
- for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
- E = RD->bases_end(); I != E; ++I) {
-
- // Don't layout virtual bases.
- if (I->isVirtual())
- continue;
-
- const CXXRecordDecl *BaseDecl =
- cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
-
- const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
- CharUnits BaseOffset = Base.getBaseOffset() +
- Layout.getBaseClassOffset(BaseDecl);
-
- // Layout the VTT for this base.
- LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/false);
- }
-}
-
-void
-VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base,
- bool BaseIsMorallyVirtual,
- uint64_t VTableIndex,
- const CXXRecordDecl *VTableClass,
- VisitedVirtualBasesSetTy &VBases) {
- const CXXRecordDecl *RD = Base.getBase();
-
- // We're not interested in bases that don't have virtual bases, and not
- // morally virtual bases.
- if (!RD->getNumVBases() && !BaseIsMorallyVirtual)
- return;
-
- 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());
-
- // Itanium C++ ABI 2.6.2:
- // Secondary virtual pointers are present for all bases with either
- // virtual bases or virtual function declarations overridden along a
- // virtual path.
- //
- // If the base class is not dynamic, we don't want to add it, nor any
- // of its base classes.
- if (!BaseDecl->isDynamicClass())
- continue;
-
- bool BaseDeclIsMorallyVirtual = BaseIsMorallyVirtual;
- bool BaseDeclIsNonVirtualPrimaryBase = false;
- CharUnits BaseOffset;
- if (I->isVirtual()) {
- // Ignore virtual bases that we've already visited.
- if (!VBases.insert(BaseDecl))
- continue;
-
- BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
- BaseDeclIsMorallyVirtual = true;
- } else {
- const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
-
- BaseOffset = Base.getBaseOffset() +
- Layout.getBaseClassOffset(BaseDecl);
-
- if (!Layout.isPrimaryBaseVirtual() &&
- Layout.getPrimaryBase() == BaseDecl)
- BaseDeclIsNonVirtualPrimaryBase = true;
- }
-
- // Itanium C++ ABI 2.6.2:
- // Secondary virtual pointers: for each base class X which (a) has virtual
- // bases or is reachable along a virtual path from D, and (b) is not a
- // non-virtual primary base, the address of the virtual table for X-in-D
- // or an appropriate construction virtual table.
- if (!BaseDeclIsNonVirtualPrimaryBase &&
- (BaseDecl->getNumVBases() || BaseDeclIsMorallyVirtual)) {
- // Add the vtable pointer.
- AddVTablePointer(BaseSubobject(BaseDecl, BaseOffset), VTableIndex,
- VTableClass);
- }
-
- // And lay out the secondary virtual pointers for the base class.
- LayoutSecondaryVirtualPointers(BaseSubobject(BaseDecl, BaseOffset),
- BaseDeclIsMorallyVirtual, VTableIndex,
- VTableClass, VBases);
- }
-}
-
-void
-VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base,
- uint64_t VTableIndex) {
- VisitedVirtualBasesSetTy VBases;
- LayoutSecondaryVirtualPointers(Base, /*BaseIsMorallyVirtual=*/false,
- VTableIndex, Base.getBase(), VBases);
-}
-
-void VTTBuilder::LayoutVirtualVTTs(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());
-
- // Check if this is a virtual base.
- if (I->isVirtual()) {
- // Check if we've seen this base before.
- if (!VBases.insert(BaseDecl))
- continue;
-
- CharUnits BaseOffset =
- MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
-
- LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/true);
- }
-
- // We only need to layout virtual VTTs for this base if it actually has
- // virtual bases.
- if (BaseDecl->getNumVBases())
- LayoutVirtualVTTs(BaseDecl, VBases);
- }
-}
-
-void VTTBuilder::LayoutVTT(BaseSubobject Base, bool BaseIsVirtual) {
- const CXXRecordDecl *RD = Base.getBase();
-
- // Itanium C++ ABI 2.6.2:
- // An array of virtual table addresses, called the VTT, is declared for
- // each class type that has indirect or direct virtual base classes.
- if (RD->getNumVBases() == 0)
- return;
-
- bool IsPrimaryVTT = Base.getBase() == MostDerivedClass;
-
- if (!IsPrimaryVTT) {
- // Remember the sub-VTT index.
- SubVTTIndicies[Base] = VTTComponents.size();
- }
-
- uint64_t VTableIndex = VTTVTables.size();
- VTTVTables.push_back(VTTVTable(Base, BaseIsVirtual));
-
- // Add the primary vtable pointer.
- AddVTablePointer(Base, VTableIndex, RD);
-
- // Add the secondary VTTs.
- LayoutSecondaryVTTs(Base);
-
- // Add the secondary virtual pointers.
- LayoutSecondaryVirtualPointers(Base, VTableIndex);
-
- // If this is the primary VTT, we want to lay out virtual VTTs as well.
- if (IsPrimaryVTT) {
- VisitedVirtualBasesSetTy VBases;
- LayoutVirtualVTTs(Base.getBase(), VBases);
- }
-}
-
-}
-
void
CodeGenVTables::EmitVTTDefinition(llvm::GlobalVariable *VTT,
llvm::GlobalVariable::LinkageTypes Linkage,
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