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diff --git a/contrib/llvm/tools/clang/include/clang/AST/VTableBuilder.h b/contrib/llvm/tools/clang/include/clang/AST/VTableBuilder.h
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+//===--- VTableBuilder.h - C++ vtable 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 tables.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_VTABLEBUILDER_H
+#define LLVM_CLANG_AST_VTABLEBUILDER_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 CXXRecordDecl;
+
+/// VTableComponent - Represents a single component in a vtable.
+class VTableComponent {
+public:
+ enum Kind {
+ CK_VCallOffset,
+ CK_VBaseOffset,
+ CK_OffsetToTop,
+ CK_RTTI,
+ CK_FunctionPointer,
+
+ /// CK_CompleteDtorPointer - A pointer to the complete destructor.
+ CK_CompleteDtorPointer,
+
+ /// CK_DeletingDtorPointer - A pointer to the deleting destructor.
+ CK_DeletingDtorPointer,
+
+ /// CK_UnusedFunctionPointer - In some cases, a vtable function pointer
+ /// will end up never being called. Such vtable function pointers are
+ /// represented as a CK_UnusedFunctionPointer.
+ CK_UnusedFunctionPointer
+ };
+
+ VTableComponent() { }
+
+ static VTableComponent MakeVCallOffset(CharUnits Offset) {
+ return VTableComponent(CK_VCallOffset, Offset);
+ }
+
+ static VTableComponent MakeVBaseOffset(CharUnits Offset) {
+ return VTableComponent(CK_VBaseOffset, Offset);
+ }
+
+ static VTableComponent MakeOffsetToTop(CharUnits Offset) {
+ return VTableComponent(CK_OffsetToTop, Offset);
+ }
+
+ static VTableComponent MakeRTTI(const CXXRecordDecl *RD) {
+ return VTableComponent(CK_RTTI, reinterpret_cast<uintptr_t>(RD));
+ }
+
+ static VTableComponent MakeFunction(const CXXMethodDecl *MD) {
+ assert(!isa<CXXDestructorDecl>(MD) &&
+ "Don't use MakeFunction with destructors!");
+
+ return VTableComponent(CK_FunctionPointer,
+ reinterpret_cast<uintptr_t>(MD));
+ }
+
+ static VTableComponent MakeCompleteDtor(const CXXDestructorDecl *DD) {
+ return VTableComponent(CK_CompleteDtorPointer,
+ reinterpret_cast<uintptr_t>(DD));
+ }
+
+ static VTableComponent MakeDeletingDtor(const CXXDestructorDecl *DD) {
+ return VTableComponent(CK_DeletingDtorPointer,
+ reinterpret_cast<uintptr_t>(DD));
+ }
+
+ static VTableComponent MakeUnusedFunction(const CXXMethodDecl *MD) {
+ assert(!isa<CXXDestructorDecl>(MD) &&
+ "Don't use MakeUnusedFunction with destructors!");
+ return VTableComponent(CK_UnusedFunctionPointer,
+ reinterpret_cast<uintptr_t>(MD));
+ }
+
+ static VTableComponent getFromOpaqueInteger(uint64_t I) {
+ return VTableComponent(I);
+ }
+
+ /// getKind - Get the kind of this vtable component.
+ Kind getKind() const {
+ return (Kind)(Value & 0x7);
+ }
+
+ CharUnits getVCallOffset() const {
+ assert(getKind() == CK_VCallOffset && "Invalid component kind!");
+
+ return getOffset();
+ }
+
+ CharUnits getVBaseOffset() const {
+ assert(getKind() == CK_VBaseOffset && "Invalid component kind!");
+
+ return getOffset();
+ }
+
+ CharUnits getOffsetToTop() const {
+ assert(getKind() == CK_OffsetToTop && "Invalid component kind!");
+
+ return getOffset();
+ }
+
+ const CXXRecordDecl *getRTTIDecl() const {
+ assert(getKind() == CK_RTTI && "Invalid component kind!");
+
+ return reinterpret_cast<CXXRecordDecl *>(getPointer());
+ }
+
+ const CXXMethodDecl *getFunctionDecl() const {
+ assert(getKind() == CK_FunctionPointer);
+
+ return reinterpret_cast<CXXMethodDecl *>(getPointer());
+ }
+
+ const CXXDestructorDecl *getDestructorDecl() const {
+ assert((getKind() == CK_CompleteDtorPointer ||
+ getKind() == CK_DeletingDtorPointer) && "Invalid component kind!");
+
+ return reinterpret_cast<CXXDestructorDecl *>(getPointer());
+ }
+
+ const CXXMethodDecl *getUnusedFunctionDecl() const {
+ assert(getKind() == CK_UnusedFunctionPointer);
+
+ return reinterpret_cast<CXXMethodDecl *>(getPointer());
+ }
+
+private:
+ VTableComponent(Kind ComponentKind, CharUnits Offset) {
+ assert((ComponentKind == CK_VCallOffset ||
+ ComponentKind == CK_VBaseOffset ||
+ ComponentKind == CK_OffsetToTop) && "Invalid component kind!");
+ assert(Offset.getQuantity() <= ((1LL << 56) - 1) && "Offset is too big!");
+
+ Value = ((Offset.getQuantity() << 3) | ComponentKind);
+ }
+
+ VTableComponent(Kind ComponentKind, uintptr_t Ptr) {
+ assert((ComponentKind == CK_RTTI ||
+ ComponentKind == CK_FunctionPointer ||
+ ComponentKind == CK_CompleteDtorPointer ||
+ ComponentKind == CK_DeletingDtorPointer ||
+ ComponentKind == CK_UnusedFunctionPointer) &&
+ "Invalid component kind!");
+
+ assert((Ptr & 7) == 0 && "Pointer not sufficiently aligned!");
+
+ Value = Ptr | ComponentKind;
+ }
+
+ CharUnits getOffset() const {
+ assert((getKind() == CK_VCallOffset || getKind() == CK_VBaseOffset ||
+ getKind() == CK_OffsetToTop) && "Invalid component kind!");
+
+ return CharUnits::fromQuantity(Value >> 3);
+ }
+
+ uintptr_t getPointer() const {
+ assert((getKind() == CK_RTTI ||
+ getKind() == CK_FunctionPointer ||
+ getKind() == CK_CompleteDtorPointer ||
+ getKind() == CK_DeletingDtorPointer ||
+ getKind() == CK_UnusedFunctionPointer) &&
+ "Invalid component kind!");
+
+ return static_cast<uintptr_t>(Value & ~7ULL);
+ }
+
+ explicit VTableComponent(uint64_t Value)
+ : Value(Value) { }
+
+ /// The kind is stored in the lower 3 bits of the value. For offsets, we
+ /// make use of the facts that classes can't be larger than 2^55 bytes,
+ /// so we store the offset in the lower part of the 61 bytes that remain.
+ /// (The reason that we're not simply using a PointerIntPair here is that we
+ /// need the offsets to be 64-bit, even when on a 32-bit machine).
+ int64_t Value;
+};
+
+class VTableLayout {
+public:
+ typedef std::pair<uint64_t, ThunkInfo> VTableThunkTy;
+ typedef SmallVector<ThunkInfo, 1> ThunkInfoVectorTy;
+
+ typedef const VTableComponent *vtable_component_iterator;
+ typedef const VTableThunkTy *vtable_thunk_iterator;
+
+ typedef llvm::DenseMap<BaseSubobject, uint64_t> AddressPointsMapTy;
+private:
+ uint64_t NumVTableComponents;
+ VTableComponent *VTableComponents;
+
+ /// VTableThunks - Contains thunks needed by vtables.
+ uint64_t NumVTableThunks;
+ VTableThunkTy *VTableThunks;
+
+ /// Address points - Address points for all vtables.
+ AddressPointsMapTy AddressPoints;
+
+public:
+ VTableLayout(uint64_t NumVTableComponents,
+ const VTableComponent *VTableComponents,
+ uint64_t NumVTableThunks,
+ const VTableThunkTy *VTableThunks,
+ const AddressPointsMapTy &AddressPoints);
+ ~VTableLayout();
+
+ uint64_t getNumVTableComponents() const {
+ return NumVTableComponents;
+ }
+
+ vtable_component_iterator vtable_component_begin() const {
+ return VTableComponents;
+ }
+
+ vtable_component_iterator vtable_component_end() const {
+ return VTableComponents+NumVTableComponents;
+ }
+
+ uint64_t getNumVTableThunks() const {
+ return NumVTableThunks;
+ }
+
+ vtable_thunk_iterator vtable_thunk_begin() const {
+ return VTableThunks;
+ }
+
+ vtable_thunk_iterator vtable_thunk_end() const {
+ return VTableThunks+NumVTableThunks;
+ }
+
+ uint64_t getAddressPoint(BaseSubobject Base) const {
+ assert(AddressPoints.count(Base) &&
+ "Did not find address point!");
+
+ uint64_t AddressPoint = AddressPoints.lookup(Base);
+ assert(AddressPoint && "Address point must not be zero!");
+
+ return AddressPoint;
+ }
+
+ const AddressPointsMapTy &getAddressPoints() const {
+ return AddressPoints;
+ }
+};
+
+class VTableContext {
+ ASTContext &Context;
+
+public:
+ typedef SmallVector<std::pair<uint64_t, ThunkInfo>, 1>
+ VTableThunksTy;
+ typedef SmallVector<ThunkInfo, 1> ThunkInfoVectorTy;
+
+private:
+ /// MethodVTableIndices - Contains the index (relative to the vtable address
+ /// point) where the function pointer for a virtual function is stored.
+ typedef llvm::DenseMap<GlobalDecl, int64_t> MethodVTableIndicesTy;
+ MethodVTableIndicesTy MethodVTableIndices;
+
+ typedef llvm::DenseMap<const CXXRecordDecl *, const VTableLayout *>
+ VTableLayoutMapTy;
+ VTableLayoutMapTy VTableLayouts;
+
+ /// NumVirtualFunctionPointers - Contains the number of virtual function
+ /// pointers in the vtable for a given record decl.
+ llvm::DenseMap<const CXXRecordDecl *, uint64_t> NumVirtualFunctionPointers;
+
+ typedef std::pair<const CXXRecordDecl *,
+ const CXXRecordDecl *> ClassPairTy;
+
+ /// VirtualBaseClassOffsetOffsets - Contains the vtable offset (relative to
+ /// the address point) in chars where the offsets for virtual bases of a class
+ /// are stored.
+ typedef llvm::DenseMap<ClassPairTy, CharUnits>
+ VirtualBaseClassOffsetOffsetsMapTy;
+ VirtualBaseClassOffsetOffsetsMapTy VirtualBaseClassOffsetOffsets;
+
+ typedef llvm::DenseMap<const CXXMethodDecl *, ThunkInfoVectorTy> ThunksMapTy;
+
+ /// Thunks - Contains all thunks that a given method decl will need.
+ ThunksMapTy Thunks;
+
+ void ComputeMethodVTableIndices(const CXXRecordDecl *RD);
+
+ /// ComputeVTableRelatedInformation - Compute and store all vtable related
+ /// information (vtable layout, vbase offset offsets, thunks etc) for the
+ /// given record decl.
+ void ComputeVTableRelatedInformation(const CXXRecordDecl *RD);
+
+public:
+ VTableContext(ASTContext &Context) : Context(Context) {}
+ ~VTableContext();
+
+ const VTableLayout &getVTableLayout(const CXXRecordDecl *RD) {
+ ComputeVTableRelatedInformation(RD);
+ assert(VTableLayouts.count(RD) && "No layout for this record decl!");
+
+ return *VTableLayouts[RD];
+ }
+
+ VTableLayout *
+ createConstructionVTableLayout(const CXXRecordDecl *MostDerivedClass,
+ CharUnits MostDerivedClassOffset,
+ bool MostDerivedClassIsVirtual,
+ const CXXRecordDecl *LayoutClass);
+
+ const ThunkInfoVectorTy *getThunkInfo(const CXXMethodDecl *MD) {
+ ComputeVTableRelatedInformation(MD->getParent());
+
+ ThunksMapTy::const_iterator I = Thunks.find(MD);
+ if (I == Thunks.end()) {
+ // We did not find a thunk for this method.
+ return 0;
+ }
+
+ return &I->second;
+ }
+
+ /// getNumVirtualFunctionPointers - Return the number of virtual function
+ /// pointers in the vtable for a given record decl.
+ uint64_t getNumVirtualFunctionPointers(const CXXRecordDecl *RD);
+
+ /// getMethodVTableIndex - Return the index (relative to the vtable address
+ /// point) where the function pointer for the given virtual function is
+ /// stored.
+ uint64_t getMethodVTableIndex(GlobalDecl GD);
+
+ /// getVirtualBaseOffsetOffset - Return the offset in chars (relative to the
+ /// vtable address point) where the offset of the virtual base that contains
+ /// the given base is stored, otherwise, if no virtual base contains the given
+ /// class, return 0. Base must be a virtual base class or an unambigious
+ /// base.
+ CharUnits getVirtualBaseOffsetOffset(const CXXRecordDecl *RD,
+ const CXXRecordDecl *VBase);
+};
+
+}
+
+#endif