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diff --git a/clang/lib/CodeGen/CGRTTI.cpp b/clang/lib/CodeGen/CGRTTI.cpp
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+++ b/clang/lib/CodeGen/CGRTTI.cpp
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+//===--- CGCXXRTTI.cpp - Emit LLVM Code for C++ RTTI descriptors ----------===//
+//
+// 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 C++ code generation of RTTI descriptors.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenModule.h"
+#include "CGCXXABI.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/AST/Type.h"
+#include "clang/Frontend/CodeGenOptions.h"
+#include "CGObjCRuntime.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+namespace {
+class RTTIBuilder {
+ CodeGenModule &CGM; // Per-module state.
+ llvm::LLVMContext &VMContext;
+
+ /// Fields - The fields of the RTTI descriptor currently being built.
+ SmallVector<llvm::Constant *, 16> Fields;
+
+ /// GetAddrOfTypeName - Returns the mangled type name of the given type.
+ llvm::GlobalVariable *
+ GetAddrOfTypeName(QualType Ty, llvm::GlobalVariable::LinkageTypes Linkage);
+
+ /// GetAddrOfExternalRTTIDescriptor - Returns the constant for the RTTI
+ /// descriptor of the given type.
+ llvm::Constant *GetAddrOfExternalRTTIDescriptor(QualType Ty);
+
+ /// BuildVTablePointer - Build the vtable pointer for the given type.
+ void BuildVTablePointer(const Type *Ty);
+
+ /// BuildSIClassTypeInfo - Build an abi::__si_class_type_info, used for single
+ /// inheritance, according to the Itanium C++ ABI, 2.9.5p6b.
+ void BuildSIClassTypeInfo(const CXXRecordDecl *RD);
+
+ /// BuildVMIClassTypeInfo - Build an abi::__vmi_class_type_info, used for
+ /// classes with bases that do not satisfy the abi::__si_class_type_info
+ /// constraints, according ti the Itanium C++ ABI, 2.9.5p5c.
+ void BuildVMIClassTypeInfo(const CXXRecordDecl *RD);
+
+ /// BuildPointerTypeInfo - Build an abi::__pointer_type_info struct, used
+ /// for pointer types.
+ void BuildPointerTypeInfo(QualType PointeeTy);
+
+ /// BuildObjCObjectTypeInfo - Build the appropriate kind of
+ /// type_info for an object type.
+ void BuildObjCObjectTypeInfo(const ObjCObjectType *Ty);
+
+ /// BuildPointerToMemberTypeInfo - Build an abi::__pointer_to_member_type_info
+ /// struct, used for member pointer types.
+ void BuildPointerToMemberTypeInfo(const MemberPointerType *Ty);
+
+public:
+ RTTIBuilder(CodeGenModule &CGM) : CGM(CGM),
+ VMContext(CGM.getModule().getContext()) { }
+
+ // Pointer type info flags.
+ enum {
+ /// PTI_Const - Type has const qualifier.
+ PTI_Const = 0x1,
+
+ /// PTI_Volatile - Type has volatile qualifier.
+ PTI_Volatile = 0x2,
+
+ /// PTI_Restrict - Type has restrict qualifier.
+ PTI_Restrict = 0x4,
+
+ /// PTI_Incomplete - Type is incomplete.
+ PTI_Incomplete = 0x8,
+
+ /// PTI_ContainingClassIncomplete - Containing class is incomplete.
+ /// (in pointer to member).
+ PTI_ContainingClassIncomplete = 0x10
+ };
+
+ // VMI type info flags.
+ enum {
+ /// VMI_NonDiamondRepeat - Class has non-diamond repeated inheritance.
+ VMI_NonDiamondRepeat = 0x1,
+
+ /// VMI_DiamondShaped - Class is diamond shaped.
+ VMI_DiamondShaped = 0x2
+ };
+
+ // Base class type info flags.
+ enum {
+ /// BCTI_Virtual - Base class is virtual.
+ BCTI_Virtual = 0x1,
+
+ /// BCTI_Public - Base class is public.
+ BCTI_Public = 0x2
+ };
+
+ /// BuildTypeInfo - Build the RTTI type info struct for the given type.
+ ///
+ /// \param Force - true to force the creation of this RTTI value
+ /// \param ForEH - true if this is for exception handling
+ llvm::Constant *BuildTypeInfo(QualType Ty, bool Force = false);
+};
+}
+
+llvm::GlobalVariable *
+RTTIBuilder::GetAddrOfTypeName(QualType Ty,
+ llvm::GlobalVariable::LinkageTypes Linkage) {
+ SmallString<256> OutName;
+ llvm::raw_svector_ostream Out(OutName);
+ CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(Ty, Out);
+ Out.flush();
+ StringRef Name = OutName.str();
+
+ // We know that the mangled name of the type starts at index 4 of the
+ // mangled name of the typename, so we can just index into it in order to
+ // get the mangled name of the type.
+ llvm::Constant *Init = llvm::ConstantDataArray::getString(VMContext,
+ Name.substr(4));
+
+ llvm::GlobalVariable *GV =
+ CGM.CreateOrReplaceCXXRuntimeVariable(Name, Init->getType(), Linkage);
+
+ GV->setInitializer(Init);
+
+ return GV;
+}
+
+llvm::Constant *RTTIBuilder::GetAddrOfExternalRTTIDescriptor(QualType Ty) {
+ // Mangle the RTTI name.
+ SmallString<256> OutName;
+ llvm::raw_svector_ostream Out(OutName);
+ CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
+ Out.flush();
+ StringRef Name = OutName.str();
+
+ // Look for an existing global.
+ llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(Name);
+
+ if (!GV) {
+ // Create a new global variable.
+ GV = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8PtrTy,
+ /*Constant=*/true,
+ llvm::GlobalValue::ExternalLinkage, 0, Name);
+ }
+
+ return llvm::ConstantExpr::getBitCast(GV, CGM.Int8PtrTy);
+}
+
+/// TypeInfoIsInStandardLibrary - Given a builtin type, returns whether the type
+/// info for that type is defined in the standard library.
+static bool TypeInfoIsInStandardLibrary(const BuiltinType *Ty) {
+ // Itanium C++ ABI 2.9.2:
+ // Basic type information (e.g. for "int", "bool", etc.) will be kept in
+ // the run-time support library. Specifically, the run-time support
+ // library should contain type_info objects for the types X, X* and
+ // X const*, for every X in: void, std::nullptr_t, bool, wchar_t, char,
+ // unsigned char, signed char, short, unsigned short, int, unsigned int,
+ // long, unsigned long, long long, unsigned long long, float, double,
+ // long double, char16_t, char32_t, and the IEEE 754r decimal and
+ // half-precision floating point types.
+ switch (Ty->getKind()) {
+ case BuiltinType::Void:
+ case BuiltinType::NullPtr:
+ case BuiltinType::Bool:
+ case BuiltinType::WChar_S:
+ case BuiltinType::WChar_U:
+ case BuiltinType::Char_U:
+ case BuiltinType::Char_S:
+ case BuiltinType::UChar:
+ case BuiltinType::SChar:
+ case BuiltinType::Short:
+ case BuiltinType::UShort:
+ case BuiltinType::Int:
+ case BuiltinType::UInt:
+ case BuiltinType::Long:
+ case BuiltinType::ULong:
+ case BuiltinType::LongLong:
+ case BuiltinType::ULongLong:
+ case BuiltinType::Half:
+ case BuiltinType::Float:
+ case BuiltinType::Double:
+ case BuiltinType::LongDouble:
+ case BuiltinType::Char16:
+ case BuiltinType::Char32:
+ case BuiltinType::Int128:
+ case BuiltinType::UInt128:
+ return true;
+
+ case BuiltinType::Dependent:
+#define BUILTIN_TYPE(Id, SingletonId)
+#define PLACEHOLDER_TYPE(Id, SingletonId) \
+ case BuiltinType::Id:
+#include "clang/AST/BuiltinTypes.def"
+ llvm_unreachable("asking for RRTI for a placeholder type!");
+
+ case BuiltinType::ObjCId:
+ case BuiltinType::ObjCClass:
+ case BuiltinType::ObjCSel:
+ llvm_unreachable("FIXME: Objective-C types are unsupported!");
+ }
+
+ llvm_unreachable("Invalid BuiltinType Kind!");
+}
+
+static bool TypeInfoIsInStandardLibrary(const PointerType *PointerTy) {
+ QualType PointeeTy = PointerTy->getPointeeType();
+ const BuiltinType *BuiltinTy = dyn_cast<BuiltinType>(PointeeTy);
+ if (!BuiltinTy)
+ return false;
+
+ // Check the qualifiers.
+ Qualifiers Quals = PointeeTy.getQualifiers();
+ Quals.removeConst();
+
+ if (!Quals.empty())
+ return false;
+
+ return TypeInfoIsInStandardLibrary(BuiltinTy);
+}
+
+/// IsStandardLibraryRTTIDescriptor - Returns whether the type
+/// information for the given type exists in the standard library.
+static bool IsStandardLibraryRTTIDescriptor(QualType Ty) {
+ // Type info for builtin types is defined in the standard library.
+ if (const BuiltinType *BuiltinTy = dyn_cast<BuiltinType>(Ty))
+ return TypeInfoIsInStandardLibrary(BuiltinTy);
+
+ // Type info for some pointer types to builtin types is defined in the
+ // standard library.
+ if (const PointerType *PointerTy = dyn_cast<PointerType>(Ty))
+ return TypeInfoIsInStandardLibrary(PointerTy);
+
+ return false;
+}
+
+/// ShouldUseExternalRTTIDescriptor - Returns whether the type information for
+/// the given type exists somewhere else, and that we should not emit the type
+/// information in this translation unit. Assumes that it is not a
+/// standard-library type.
+static bool ShouldUseExternalRTTIDescriptor(CodeGenModule &CGM, QualType Ty) {
+ ASTContext &Context = CGM.getContext();
+
+ // If RTTI is disabled, don't consider key functions.
+ if (!Context.getLangOpts().RTTI) return false;
+
+ if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
+ const CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
+ if (!RD->hasDefinition())
+ return false;
+
+ if (!RD->isDynamicClass())
+ return false;
+
+ return !CGM.getVTables().ShouldEmitVTableInThisTU(RD);
+ }
+
+ return false;
+}
+
+/// IsIncompleteClassType - Returns whether the given record type is incomplete.
+static bool IsIncompleteClassType(const RecordType *RecordTy) {
+ return !RecordTy->getDecl()->isCompleteDefinition();
+}
+
+/// ContainsIncompleteClassType - Returns whether the given type contains an
+/// incomplete class type. This is true if
+///
+/// * The given type is an incomplete class type.
+/// * The given type is a pointer type whose pointee type contains an
+/// incomplete class type.
+/// * The given type is a member pointer type whose class is an incomplete
+/// class type.
+/// * The given type is a member pointer type whoise pointee type contains an
+/// incomplete class type.
+/// is an indirect or direct pointer to an incomplete class type.
+static bool ContainsIncompleteClassType(QualType Ty) {
+ if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
+ if (IsIncompleteClassType(RecordTy))
+ return true;
+ }
+
+ if (const PointerType *PointerTy = dyn_cast<PointerType>(Ty))
+ return ContainsIncompleteClassType(PointerTy->getPointeeType());
+
+ if (const MemberPointerType *MemberPointerTy =
+ dyn_cast<MemberPointerType>(Ty)) {
+ // Check if the class type is incomplete.
+ const RecordType *ClassType = cast<RecordType>(MemberPointerTy->getClass());
+ if (IsIncompleteClassType(ClassType))
+ return true;
+
+ return ContainsIncompleteClassType(MemberPointerTy->getPointeeType());
+ }
+
+ return false;
+}
+
+/// getTypeInfoLinkage - Return the linkage that the type info and type info
+/// name constants should have for the given type.
+static llvm::GlobalVariable::LinkageTypes
+getTypeInfoLinkage(CodeGenModule &CGM, QualType Ty) {
+ // Itanium C++ ABI 2.9.5p7:
+ // In addition, it and all of the intermediate abi::__pointer_type_info
+ // structs in the chain down to the abi::__class_type_info for the
+ // incomplete class type must be prevented from resolving to the
+ // corresponding type_info structs for the complete class type, possibly
+ // by making them local static objects. Finally, a dummy class RTTI is
+ // generated for the incomplete type that will not resolve to the final
+ // complete class RTTI (because the latter need not exist), possibly by
+ // making it a local static object.
+ if (ContainsIncompleteClassType(Ty))
+ return llvm::GlobalValue::InternalLinkage;
+
+ switch (Ty->getLinkage()) {
+ case NoLinkage:
+ case InternalLinkage:
+ case UniqueExternalLinkage:
+ return llvm::GlobalValue::InternalLinkage;
+
+ case ExternalLinkage:
+ if (!CGM.getLangOpts().RTTI) {
+ // RTTI is not enabled, which means that this type info struct is going
+ // to be used for exception handling. Give it linkonce_odr linkage.
+ return llvm::GlobalValue::LinkOnceODRLinkage;
+ }
+
+ if (const RecordType *Record = dyn_cast<RecordType>(Ty)) {
+ const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
+ if (RD->hasAttr<WeakAttr>())
+ return llvm::GlobalValue::WeakODRLinkage;
+ if (RD->isDynamicClass())
+ return CGM.getVTableLinkage(RD);
+ }
+
+ return llvm::GlobalValue::LinkOnceODRLinkage;
+ }
+
+ llvm_unreachable("Invalid linkage!");
+}
+
+// CanUseSingleInheritance - Return whether the given record decl has a "single,
+// public, non-virtual base at offset zero (i.e. the derived class is dynamic
+// iff the base is)", according to Itanium C++ ABI, 2.95p6b.
+static bool CanUseSingleInheritance(const CXXRecordDecl *RD) {
+ // Check the number of bases.
+ if (RD->getNumBases() != 1)
+ return false;
+
+ // Get the base.
+ CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin();
+
+ // Check that the base is not virtual.
+ if (Base->isVirtual())
+ return false;
+
+ // Check that the base is public.
+ if (Base->getAccessSpecifier() != AS_public)
+ return false;
+
+ // Check that the class is dynamic iff the base is.
+ const CXXRecordDecl *BaseDecl =
+ cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
+ if (!BaseDecl->isEmpty() &&
+ BaseDecl->isDynamicClass() != RD->isDynamicClass())
+ return false;
+
+ return true;
+}
+
+void RTTIBuilder::BuildVTablePointer(const Type *Ty) {
+ // abi::__class_type_info.
+ static const char * const ClassTypeInfo =
+ "_ZTVN10__cxxabiv117__class_type_infoE";
+ // abi::__si_class_type_info.
+ static const char * const SIClassTypeInfo =
+ "_ZTVN10__cxxabiv120__si_class_type_infoE";
+ // abi::__vmi_class_type_info.
+ static const char * const VMIClassTypeInfo =
+ "_ZTVN10__cxxabiv121__vmi_class_type_infoE";
+
+ const char *VTableName = 0;
+
+ switch (Ty->getTypeClass()) {
+#define TYPE(Class, Base)
+#define ABSTRACT_TYPE(Class, Base)
+#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
+#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
+#define DEPENDENT_TYPE(Class, Base) case Type::Class:
+#include "clang/AST/TypeNodes.def"
+ llvm_unreachable("Non-canonical and dependent types shouldn't get here");
+
+ case Type::LValueReference:
+ case Type::RValueReference:
+ llvm_unreachable("References shouldn't get here");
+
+ case Type::Builtin:
+ // GCC treats vector and complex types as fundamental types.
+ case Type::Vector:
+ case Type::ExtVector:
+ case Type::Complex:
+ case Type::Atomic:
+ // FIXME: GCC treats block pointers as fundamental types?!
+ case Type::BlockPointer:
+ // abi::__fundamental_type_info.
+ VTableName = "_ZTVN10__cxxabiv123__fundamental_type_infoE";
+ break;
+
+ case Type::ConstantArray:
+ case Type::IncompleteArray:
+ case Type::VariableArray:
+ // abi::__array_type_info.
+ VTableName = "_ZTVN10__cxxabiv117__array_type_infoE";
+ break;
+
+ case Type::FunctionNoProto:
+ case Type::FunctionProto:
+ // abi::__function_type_info.
+ VTableName = "_ZTVN10__cxxabiv120__function_type_infoE";
+ break;
+
+ case Type::Enum:
+ // abi::__enum_type_info.
+ VTableName = "_ZTVN10__cxxabiv116__enum_type_infoE";
+ break;
+
+ case Type::Record: {
+ const CXXRecordDecl *RD =
+ cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
+
+ if (!RD->hasDefinition() || !RD->getNumBases()) {
+ VTableName = ClassTypeInfo;
+ } else if (CanUseSingleInheritance(RD)) {
+ VTableName = SIClassTypeInfo;
+ } else {
+ VTableName = VMIClassTypeInfo;
+ }
+
+ break;
+ }
+
+ case Type::ObjCObject:
+ // Ignore protocol qualifiers.
+ Ty = cast<ObjCObjectType>(Ty)->getBaseType().getTypePtr();
+
+ // Handle id and Class.
+ if (isa<BuiltinType>(Ty)) {
+ VTableName = ClassTypeInfo;
+ break;
+ }
+
+ assert(isa<ObjCInterfaceType>(Ty));
+ // Fall through.
+
+ case Type::ObjCInterface:
+ if (cast<ObjCInterfaceType>(Ty)->getDecl()->getSuperClass()) {
+ VTableName = SIClassTypeInfo;
+ } else {
+ VTableName = ClassTypeInfo;
+ }
+ break;
+
+ case Type::ObjCObjectPointer:
+ case Type::Pointer:
+ // abi::__pointer_type_info.
+ VTableName = "_ZTVN10__cxxabiv119__pointer_type_infoE";
+ break;
+
+ case Type::MemberPointer:
+ // abi::__pointer_to_member_type_info.
+ VTableName = "_ZTVN10__cxxabiv129__pointer_to_member_type_infoE";
+ break;
+ }
+
+ llvm::Constant *VTable =
+ CGM.getModule().getOrInsertGlobal(VTableName, CGM.Int8PtrTy);
+
+ llvm::Type *PtrDiffTy =
+ CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
+
+ // The vtable address point is 2.
+ llvm::Constant *Two = llvm::ConstantInt::get(PtrDiffTy, 2);
+ VTable = llvm::ConstantExpr::getInBoundsGetElementPtr(VTable, Two);
+ VTable = llvm::ConstantExpr::getBitCast(VTable, CGM.Int8PtrTy);
+
+ Fields.push_back(VTable);
+}
+
+// maybeUpdateRTTILinkage - Will update the linkage of the RTTI data structures
+// from available_externally to the correct linkage if necessary. An example of
+// this is:
+//
+// struct A {
+// virtual void f();
+// };
+//
+// const std::type_info &g() {
+// return typeid(A);
+// }
+//
+// void A::f() { }
+//
+// When we're generating the typeid(A) expression, we do not yet know that
+// A's key function is defined in this translation unit, so we will give the
+// typeinfo and typename structures available_externally linkage. When A::f
+// forces the vtable to be generated, we need to change the linkage of the
+// typeinfo and typename structs, otherwise we'll end up with undefined
+// externals when linking.
+static void
+maybeUpdateRTTILinkage(CodeGenModule &CGM, llvm::GlobalVariable *GV,
+ QualType Ty) {
+ // We're only interested in globals with available_externally linkage.
+ if (!GV->hasAvailableExternallyLinkage())
+ return;
+
+ // Get the real linkage for the type.
+ llvm::GlobalVariable::LinkageTypes Linkage = getTypeInfoLinkage(CGM, Ty);
+
+ // If variable is supposed to have available_externally linkage, we don't
+ // need to do anything.
+ if (Linkage == llvm::GlobalVariable::AvailableExternallyLinkage)
+ return;
+
+ // Update the typeinfo linkage.
+ GV->setLinkage(Linkage);
+
+ // Get the typename global.
+ SmallString<256> OutName;
+ llvm::raw_svector_ostream Out(OutName);
+ CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(Ty, Out);
+ Out.flush();
+ StringRef Name = OutName.str();
+
+ llvm::GlobalVariable *TypeNameGV = CGM.getModule().getNamedGlobal(Name);
+
+ assert(TypeNameGV->hasAvailableExternallyLinkage() &&
+ "Type name has different linkage from type info!");
+
+ // And update its linkage.
+ TypeNameGV->setLinkage(Linkage);
+}
+
+llvm::Constant *RTTIBuilder::BuildTypeInfo(QualType Ty, bool Force) {
+ // We want to operate on the canonical type.
+ Ty = CGM.getContext().getCanonicalType(Ty);
+
+ // Check if we've already emitted an RTTI descriptor for this type.
+ SmallString<256> OutName;
+ llvm::raw_svector_ostream Out(OutName);
+ CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
+ Out.flush();
+ StringRef Name = OutName.str();
+
+ llvm::GlobalVariable *OldGV = CGM.getModule().getNamedGlobal(Name);
+ if (OldGV && !OldGV->isDeclaration()) {
+ maybeUpdateRTTILinkage(CGM, OldGV, Ty);
+
+ return llvm::ConstantExpr::getBitCast(OldGV, CGM.Int8PtrTy);
+ }
+
+ // Check if there is already an external RTTI descriptor for this type.
+ bool IsStdLib = IsStandardLibraryRTTIDescriptor(Ty);
+ if (!Force && (IsStdLib || ShouldUseExternalRTTIDescriptor(CGM, Ty)))
+ return GetAddrOfExternalRTTIDescriptor(Ty);
+
+ // Emit the standard library with external linkage.
+ llvm::GlobalVariable::LinkageTypes Linkage;
+ if (IsStdLib)
+ Linkage = llvm::GlobalValue::ExternalLinkage;
+ else
+ Linkage = getTypeInfoLinkage(CGM, Ty);
+
+ // Add the vtable pointer.
+ BuildVTablePointer(cast<Type>(Ty));
+
+ // And the name.
+ llvm::GlobalVariable *TypeName = GetAddrOfTypeName(Ty, Linkage);
+
+ Fields.push_back(llvm::ConstantExpr::getBitCast(TypeName, CGM.Int8PtrTy));
+
+ switch (Ty->getTypeClass()) {
+#define TYPE(Class, Base)
+#define ABSTRACT_TYPE(Class, Base)
+#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
+#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
+#define DEPENDENT_TYPE(Class, Base) case Type::Class:
+#include "clang/AST/TypeNodes.def"
+ llvm_unreachable("Non-canonical and dependent types shouldn't get here");
+
+ // GCC treats vector types as fundamental types.
+ case Type::Builtin:
+ case Type::Vector:
+ case Type::ExtVector:
+ case Type::Complex:
+ case Type::BlockPointer:
+ // Itanium C++ ABI 2.9.5p4:
+ // abi::__fundamental_type_info adds no data members to std::type_info.
+ break;
+
+ case Type::LValueReference:
+ case Type::RValueReference:
+ llvm_unreachable("References shouldn't get here");
+
+ case Type::ConstantArray:
+ case Type::IncompleteArray:
+ case Type::VariableArray:
+ // Itanium C++ ABI 2.9.5p5:
+ // abi::__array_type_info adds no data members to std::type_info.
+ break;
+
+ case Type::FunctionNoProto:
+ case Type::FunctionProto:
+ // Itanium C++ ABI 2.9.5p5:
+ // abi::__function_type_info adds no data members to std::type_info.
+ break;
+
+ case Type::Enum:
+ // Itanium C++ ABI 2.9.5p5:
+ // abi::__enum_type_info adds no data members to std::type_info.
+ break;
+
+ case Type::Record: {
+ const CXXRecordDecl *RD =
+ cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
+ if (!RD->hasDefinition() || !RD->getNumBases()) {
+ // We don't need to emit any fields.
+ break;
+ }
+
+ if (CanUseSingleInheritance(RD))
+ BuildSIClassTypeInfo(RD);
+ else
+ BuildVMIClassTypeInfo(RD);
+
+ break;
+ }
+
+ case Type::ObjCObject:
+ case Type::ObjCInterface:
+ BuildObjCObjectTypeInfo(cast<ObjCObjectType>(Ty));
+ break;
+
+ case Type::ObjCObjectPointer:
+ BuildPointerTypeInfo(cast<ObjCObjectPointerType>(Ty)->getPointeeType());
+ break;
+
+ case Type::Pointer:
+ BuildPointerTypeInfo(cast<PointerType>(Ty)->getPointeeType());
+ break;
+
+ case Type::MemberPointer:
+ BuildPointerToMemberTypeInfo(cast<MemberPointerType>(Ty));
+ break;
+
+ case Type::Atomic:
+ // No fields, at least for the moment.
+ break;
+ }
+
+ llvm::Constant *Init = llvm::ConstantStruct::getAnon(Fields);
+
+ llvm::GlobalVariable *GV =
+ new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
+ /*Constant=*/true, Linkage, Init, Name);
+
+ // If there's already an old global variable, replace it with the new one.
+ if (OldGV) {
+ GV->takeName(OldGV);
+ llvm::Constant *NewPtr =
+ llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
+ OldGV->replaceAllUsesWith(NewPtr);
+ OldGV->eraseFromParent();
+ }
+
+ // GCC only relies on the uniqueness of the type names, not the
+ // type_infos themselves, so we can emit these as hidden symbols.
+ // But don't do this if we're worried about strict visibility
+ // compatibility.
+ if (const RecordType *RT = dyn_cast<RecordType>(Ty)) {
+ const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
+
+ CGM.setTypeVisibility(GV, RD, CodeGenModule::TVK_ForRTTI);
+ CGM.setTypeVisibility(TypeName, RD, CodeGenModule::TVK_ForRTTIName);
+ } else {
+ Visibility TypeInfoVisibility = DefaultVisibility;
+ if (CGM.getCodeGenOpts().HiddenWeakVTables &&
+ Linkage == llvm::GlobalValue::LinkOnceODRLinkage)
+ TypeInfoVisibility = HiddenVisibility;
+
+ // The type name should have the same visibility as the type itself.
+ Visibility ExplicitVisibility = Ty->getVisibility();
+ TypeName->setVisibility(CodeGenModule::
+ GetLLVMVisibility(ExplicitVisibility));
+
+ TypeInfoVisibility = minVisibility(TypeInfoVisibility, Ty->getVisibility());
+ GV->setVisibility(CodeGenModule::GetLLVMVisibility(TypeInfoVisibility));
+ }
+
+ GV->setUnnamedAddr(true);
+
+ return llvm::ConstantExpr::getBitCast(GV, CGM.Int8PtrTy);
+}
+
+/// ComputeQualifierFlags - Compute the pointer type info flags from the
+/// given qualifier.
+static unsigned ComputeQualifierFlags(Qualifiers Quals) {
+ unsigned Flags = 0;
+
+ if (Quals.hasConst())
+ Flags |= RTTIBuilder::PTI_Const;
+ if (Quals.hasVolatile())
+ Flags |= RTTIBuilder::PTI_Volatile;
+ if (Quals.hasRestrict())
+ Flags |= RTTIBuilder::PTI_Restrict;
+
+ return Flags;
+}
+
+/// BuildObjCObjectTypeInfo - Build the appropriate kind of type_info
+/// for the given Objective-C object type.
+void RTTIBuilder::BuildObjCObjectTypeInfo(const ObjCObjectType *OT) {
+ // Drop qualifiers.
+ const Type *T = OT->getBaseType().getTypePtr();
+ assert(isa<BuiltinType>(T) || isa<ObjCInterfaceType>(T));
+
+ // The builtin types are abi::__class_type_infos and don't require
+ // extra fields.
+ if (isa<BuiltinType>(T)) return;
+
+ ObjCInterfaceDecl *Class = cast<ObjCInterfaceType>(T)->getDecl();
+ ObjCInterfaceDecl *Super = Class->getSuperClass();
+
+ // Root classes are also __class_type_info.
+ if (!Super) return;
+
+ QualType SuperTy = CGM.getContext().getObjCInterfaceType(Super);
+
+ // Everything else is single inheritance.
+ llvm::Constant *BaseTypeInfo = RTTIBuilder(CGM).BuildTypeInfo(SuperTy);
+ Fields.push_back(BaseTypeInfo);
+}
+
+/// BuildSIClassTypeInfo - Build an abi::__si_class_type_info, used for single
+/// inheritance, according to the Itanium C++ ABI, 2.95p6b.
+void RTTIBuilder::BuildSIClassTypeInfo(const CXXRecordDecl *RD) {
+ // Itanium C++ ABI 2.9.5p6b:
+ // It adds to abi::__class_type_info a single member pointing to the
+ // type_info structure for the base type,
+ llvm::Constant *BaseTypeInfo =
+ RTTIBuilder(CGM).BuildTypeInfo(RD->bases_begin()->getType());
+ Fields.push_back(BaseTypeInfo);
+}
+
+namespace {
+ /// SeenBases - Contains virtual and non-virtual bases seen when traversing
+ /// a class hierarchy.
+ struct SeenBases {
+ llvm::SmallPtrSet<const CXXRecordDecl *, 16> NonVirtualBases;
+ llvm::SmallPtrSet<const CXXRecordDecl *, 16> VirtualBases;
+ };
+}
+
+/// ComputeVMIClassTypeInfoFlags - Compute the value of the flags member in
+/// abi::__vmi_class_type_info.
+///
+static unsigned ComputeVMIClassTypeInfoFlags(const CXXBaseSpecifier *Base,
+ SeenBases &Bases) {
+
+ unsigned Flags = 0;
+
+ const CXXRecordDecl *BaseDecl =
+ cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
+
+ if (Base->isVirtual()) {
+ if (Bases.VirtualBases.count(BaseDecl)) {
+ // If this virtual base has been seen before, then the class is diamond
+ // shaped.
+ Flags |= RTTIBuilder::VMI_DiamondShaped;
+ } else {
+ if (Bases.NonVirtualBases.count(BaseDecl))
+ Flags |= RTTIBuilder::VMI_NonDiamondRepeat;
+
+ // Mark the virtual base as seen.
+ Bases.VirtualBases.insert(BaseDecl);
+ }
+ } else {
+ if (Bases.NonVirtualBases.count(BaseDecl)) {
+ // If this non-virtual base has been seen before, then the class has non-
+ // diamond shaped repeated inheritance.
+ Flags |= RTTIBuilder::VMI_NonDiamondRepeat;
+ } else {
+ if (Bases.VirtualBases.count(BaseDecl))
+ Flags |= RTTIBuilder::VMI_NonDiamondRepeat;
+
+ // Mark the non-virtual base as seen.
+ Bases.NonVirtualBases.insert(BaseDecl);
+ }
+ }
+
+ // Walk all bases.
+ for (CXXRecordDecl::base_class_const_iterator I = BaseDecl->bases_begin(),
+ E = BaseDecl->bases_end(); I != E; ++I)
+ Flags |= ComputeVMIClassTypeInfoFlags(I, Bases);
+
+ return Flags;
+}
+
+static unsigned ComputeVMIClassTypeInfoFlags(const CXXRecordDecl *RD) {
+ unsigned Flags = 0;
+ SeenBases Bases;
+
+ // Walk all bases.
+ for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+ E = RD->bases_end(); I != E; ++I)
+ Flags |= ComputeVMIClassTypeInfoFlags(I, Bases);
+
+ return Flags;
+}
+
+/// BuildVMIClassTypeInfo - Build an abi::__vmi_class_type_info, used for
+/// classes with bases that do not satisfy the abi::__si_class_type_info
+/// constraints, according ti the Itanium C++ ABI, 2.9.5p5c.
+void RTTIBuilder::BuildVMIClassTypeInfo(const CXXRecordDecl *RD) {
+ llvm::Type *UnsignedIntLTy =
+ CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
+
+ // Itanium C++ ABI 2.9.5p6c:
+ // __flags is a word with flags describing details about the class
+ // structure, which may be referenced by using the __flags_masks
+ // enumeration. These flags refer to both direct and indirect bases.
+ unsigned Flags = ComputeVMIClassTypeInfoFlags(RD);
+ Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
+
+ // Itanium C++ ABI 2.9.5p6c:
+ // __base_count is a word with the number of direct proper base class
+ // descriptions that follow.
+ Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, RD->getNumBases()));
+
+ if (!RD->getNumBases())
+ return;
+
+ llvm::Type *LongLTy =
+ CGM.getTypes().ConvertType(CGM.getContext().LongTy);
+
+ // Now add the base class descriptions.
+
+ // Itanium C++ ABI 2.9.5p6c:
+ // __base_info[] is an array of base class descriptions -- one for every
+ // direct proper base. Each description is of the type:
+ //
+ // struct abi::__base_class_type_info {
+ // public:
+ // const __class_type_info *__base_type;
+ // long __offset_flags;
+ //
+ // enum __offset_flags_masks {
+ // __virtual_mask = 0x1,
+ // __public_mask = 0x2,
+ // __offset_shift = 8
+ // };
+ // };
+ for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+ E = RD->bases_end(); I != E; ++I) {
+ const CXXBaseSpecifier *Base = I;
+
+ // The __base_type member points to the RTTI for the base type.
+ Fields.push_back(RTTIBuilder(CGM).BuildTypeInfo(Base->getType()));
+
+ const CXXRecordDecl *BaseDecl =
+ cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
+
+ int64_t OffsetFlags = 0;
+
+ // All but the lower 8 bits of __offset_flags are a signed offset.
+ // For a non-virtual base, this is the offset in the object of the base
+ // subobject. For a virtual base, this is the offset in the virtual table of
+ // the virtual base offset for the virtual base referenced (negative).
+ CharUnits Offset;
+ if (Base->isVirtual())
+ Offset =
+ CGM.getVTableContext().getVirtualBaseOffsetOffset(RD, BaseDecl);
+ else {
+ const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
+ Offset = Layout.getBaseClassOffset(BaseDecl);
+ };
+
+ OffsetFlags = Offset.getQuantity() << 8;
+
+ // The low-order byte of __offset_flags contains flags, as given by the
+ // masks from the enumeration __offset_flags_masks.
+ if (Base->isVirtual())
+ OffsetFlags |= BCTI_Virtual;
+ if (Base->getAccessSpecifier() == AS_public)
+ OffsetFlags |= BCTI_Public;
+
+ Fields.push_back(llvm::ConstantInt::get(LongLTy, OffsetFlags));
+ }
+}
+
+/// BuildPointerTypeInfo - Build an abi::__pointer_type_info struct,
+/// used for pointer types.
+void RTTIBuilder::BuildPointerTypeInfo(QualType PointeeTy) {
+ Qualifiers Quals;
+ QualType UnqualifiedPointeeTy =
+ CGM.getContext().getUnqualifiedArrayType(PointeeTy, Quals);
+
+ // Itanium C++ ABI 2.9.5p7:
+ // __flags is a flag word describing the cv-qualification and other
+ // attributes of the type pointed to
+ unsigned Flags = ComputeQualifierFlags(Quals);
+
+ // Itanium C++ ABI 2.9.5p7:
+ // When the abi::__pbase_type_info is for a direct or indirect pointer to an
+ // incomplete class type, the incomplete target type flag is set.
+ if (ContainsIncompleteClassType(UnqualifiedPointeeTy))
+ Flags |= PTI_Incomplete;
+
+ llvm::Type *UnsignedIntLTy =
+ CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
+ Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
+
+ // Itanium C++ ABI 2.9.5p7:
+ // __pointee is a pointer to the std::type_info derivation for the
+ // unqualified type being pointed to.
+ llvm::Constant *PointeeTypeInfo =
+ RTTIBuilder(CGM).BuildTypeInfo(UnqualifiedPointeeTy);
+ Fields.push_back(PointeeTypeInfo);
+}
+
+/// BuildPointerToMemberTypeInfo - Build an abi::__pointer_to_member_type_info
+/// struct, used for member pointer types.
+void RTTIBuilder::BuildPointerToMemberTypeInfo(const MemberPointerType *Ty) {
+ QualType PointeeTy = Ty->getPointeeType();
+
+ Qualifiers Quals;
+ QualType UnqualifiedPointeeTy =
+ CGM.getContext().getUnqualifiedArrayType(PointeeTy, Quals);
+
+ // Itanium C++ ABI 2.9.5p7:
+ // __flags is a flag word describing the cv-qualification and other
+ // attributes of the type pointed to.
+ unsigned Flags = ComputeQualifierFlags(Quals);
+
+ const RecordType *ClassType = cast<RecordType>(Ty->getClass());
+
+ // Itanium C++ ABI 2.9.5p7:
+ // When the abi::__pbase_type_info is for a direct or indirect pointer to an
+ // incomplete class type, the incomplete target type flag is set.
+ if (ContainsIncompleteClassType(UnqualifiedPointeeTy))
+ Flags |= PTI_Incomplete;
+
+ if (IsIncompleteClassType(ClassType))
+ Flags |= PTI_ContainingClassIncomplete;
+
+ llvm::Type *UnsignedIntLTy =
+ CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
+ Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
+
+ // Itanium C++ ABI 2.9.5p7:
+ // __pointee is a pointer to the std::type_info derivation for the
+ // unqualified type being pointed to.
+ llvm::Constant *PointeeTypeInfo =
+ RTTIBuilder(CGM).BuildTypeInfo(UnqualifiedPointeeTy);
+ Fields.push_back(PointeeTypeInfo);
+
+ // Itanium C++ ABI 2.9.5p9:
+ // __context is a pointer to an abi::__class_type_info corresponding to the
+ // class type containing the member pointed to
+ // (e.g., the "A" in "int A::*").
+ Fields.push_back(RTTIBuilder(CGM).BuildTypeInfo(QualType(ClassType, 0)));
+}
+
+llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty,
+ bool ForEH) {
+ // Return a bogus pointer if RTTI is disabled, unless it's for EH.
+ // FIXME: should we even be calling this method if RTTI is disabled
+ // and it's not for EH?
+ if (!ForEH && !getContext().getLangOpts().RTTI)
+ return llvm::Constant::getNullValue(Int8PtrTy);
+
+ if (ForEH && Ty->isObjCObjectPointerType() && !LangOpts.NeXTRuntime)
+ return ObjCRuntime->GetEHType(Ty);
+
+ return RTTIBuilder(*this).BuildTypeInfo(Ty);
+}
+
+void CodeGenModule::EmitFundamentalRTTIDescriptor(QualType Type) {
+ QualType PointerType = Context.getPointerType(Type);
+ QualType PointerTypeConst = Context.getPointerType(Type.withConst());
+ RTTIBuilder(*this).BuildTypeInfo(Type, true);
+ RTTIBuilder(*this).BuildTypeInfo(PointerType, true);
+ RTTIBuilder(*this).BuildTypeInfo(PointerTypeConst, true);
+}
+
+void CodeGenModule::EmitFundamentalRTTIDescriptors() {
+ QualType FundamentalTypes[] = { Context.VoidTy, Context.NullPtrTy,
+ Context.BoolTy, Context.WCharTy,
+ Context.CharTy, Context.UnsignedCharTy,
+ Context.SignedCharTy, Context.ShortTy,
+ Context.UnsignedShortTy, Context.IntTy,
+ Context.UnsignedIntTy, Context.LongTy,
+ Context.UnsignedLongTy, Context.LongLongTy,
+ Context.UnsignedLongLongTy, Context.FloatTy,
+ Context.DoubleTy, Context.LongDoubleTy,
+ Context.Char16Ty, Context.Char32Ty };
+ for (unsigned i = 0; i < sizeof(FundamentalTypes)/sizeof(QualType); ++i)
+ EmitFundamentalRTTIDescriptor(FundamentalTypes[i]);
+}