diff options
Diffstat (limited to 'lib/CodeGen/CGRecordLayoutBuilder.cpp')
-rw-r--r-- | lib/CodeGen/CGRecordLayoutBuilder.cpp | 122 |
1 files changed, 98 insertions, 24 deletions
diff --git a/lib/CodeGen/CGRecordLayoutBuilder.cpp b/lib/CodeGen/CGRecordLayoutBuilder.cpp index 6302cf8..9f16875 100644 --- a/lib/CodeGen/CGRecordLayoutBuilder.cpp +++ b/lib/CodeGen/CGRecordLayoutBuilder.cpp @@ -42,6 +42,9 @@ public: typedef std::pair<const FieldDecl *, CGBitFieldInfo> LLVMBitFieldInfo; llvm::SmallVector<LLVMBitFieldInfo, 16> LLVMBitFields; + typedef std::pair<const CXXRecordDecl *, unsigned> LLVMBaseInfo; + llvm::SmallVector<LLVMBaseInfo, 16> LLVMNonVirtualBases; + /// ContainsPointerToDataMember - Whether one of the fields in this record /// layout is a pointer to data member, or a struct that contains pointer to /// data member. @@ -81,8 +84,13 @@ private: /// Returns false if the operation failed because the struct is not packed. bool LayoutFields(const RecordDecl *D); - /// LayoutBases - layout the bases and vtable pointer of a record decl. - void LayoutBases(const CXXRecordDecl *RD, const ASTRecordLayout &Layout); + /// LayoutNonVirtualBase - layout a single non-virtual base. + void LayoutNonVirtualBase(const CXXRecordDecl *BaseDecl, + uint64_t BaseOffset); + + /// LayoutNonVirtualBases - layout the non-virtual bases of a record decl. + void LayoutNonVirtualBases(const CXXRecordDecl *RD, + const ASTRecordLayout &Layout); /// LayoutField - layout a single field. Returns false if the operation failed /// because the current struct is not packed. @@ -110,6 +118,7 @@ private: /// CheckForPointerToDataMember - Check if the given type contains a pointer /// to data member. void CheckForPointerToDataMember(QualType T); + void CheckForPointerToDataMember(const CXXRecordDecl *RD); public: CGRecordLayoutBuilder(CodeGenTypes &Types) @@ -143,6 +152,7 @@ void CGRecordLayoutBuilder::Layout(const RecordDecl *D) { FieldTypes.clear(); LLVMFields.clear(); LLVMBitFields.clear(); + LLVMNonVirtualBases.clear(); LayoutFields(D); } @@ -319,8 +329,9 @@ bool CGRecordLayoutBuilder::LayoutField(const FieldDecl *D, if (const RecordType *RT = D->getType()->getAs<RecordType>()) { const RecordDecl *RD = cast<RecordDecl>(RT->getDecl()); - if (const PragmaPackAttr *PPA = RD->getAttr<PragmaPackAttr>()) { - if (PPA->getAlignment() != TypeAlignment * 8 && !Packed) + if (const MaxFieldAlignmentAttr *MFAA = + RD->getAttr<MaxFieldAlignmentAttr>()) { + if (MFAA->getAlignment() != TypeAlignment * 8 && !Packed) return false; } } @@ -435,16 +446,66 @@ void CGRecordLayoutBuilder::LayoutUnion(const RecordDecl *D) { AppendPadding(Layout.getSize() / 8, Align); } -void CGRecordLayoutBuilder::LayoutBases(const CXXRecordDecl *RD, - const ASTRecordLayout &Layout) { +void CGRecordLayoutBuilder::LayoutNonVirtualBase(const CXXRecordDecl *BaseDecl, + uint64_t BaseOffset) { + const ASTRecordLayout &Layout = + Types.getContext().getASTRecordLayout(BaseDecl); + + uint64_t NonVirtualSize = Layout.getNonVirtualSize(); + + if (BaseDecl->isEmpty()) { + // FIXME: Lay out empty bases. + return; + } + + CheckForPointerToDataMember(BaseDecl); + + // FIXME: Actually use a better type than [sizeof(BaseDecl) x i8] when we can. + AppendPadding(BaseOffset / 8, 1); + + // Append the base field. + LLVMNonVirtualBases.push_back(LLVMBaseInfo(BaseDecl, FieldTypes.size())); + + AppendBytes(NonVirtualSize / 8); +} + +void +CGRecordLayoutBuilder::LayoutNonVirtualBases(const CXXRecordDecl *RD, + const ASTRecordLayout &Layout) { + const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase(); + // Check if we need to add a vtable pointer. - if (RD->isDynamicClass() && !Layout.getPrimaryBase()) { - const llvm::Type *Int8PtrTy = - llvm::Type::getInt8PtrTy(Types.getLLVMContext()); + if (RD->isDynamicClass()) { + if (!PrimaryBase) { + const llvm::Type *FunctionType = + llvm::FunctionType::get(llvm::Type::getInt32Ty(Types.getLLVMContext()), + /*isVarArg=*/true); + const llvm::Type *VTableTy = FunctionType->getPointerTo(); + + assert(NextFieldOffsetInBytes == 0 && + "VTable pointer must come first!"); + AppendField(NextFieldOffsetInBytes, VTableTy->getPointerTo()); + } else { + // FIXME: Handle a virtual primary base. + if (!Layout.getPrimaryBaseWasVirtual()) + LayoutNonVirtualBase(PrimaryBase, 0); + } + } - assert(NextFieldOffsetInBytes == 0 && - "VTable pointer must come first!"); - AppendField(NextFieldOffsetInBytes, Int8PtrTy->getPointerTo()); + // Layout the non-virtual bases. + 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()); + + // We've already laid out the primary base. + if (BaseDecl == PrimaryBase && !Layout.getPrimaryBaseWasVirtual()) + continue; + + LayoutNonVirtualBase(BaseDecl, Layout.getBaseClassOffset(BaseDecl)); } } @@ -455,7 +516,7 @@ bool CGRecordLayoutBuilder::LayoutFields(const RecordDecl *D) { const ASTRecordLayout &Layout = Types.getContext().getASTRecordLayout(D); if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) - LayoutBases(RD, Layout); + LayoutNonVirtualBases(RD, Layout); unsigned FieldNo = 0; @@ -561,15 +622,24 @@ void CGRecordLayoutBuilder::CheckForPointerToDataMember(QualType T) { } else if (const RecordType *RT = T->getAs<RecordType>()) { const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); - // FIXME: It would be better if there was a way to explicitly compute the - // record layout instead of converting to a type. - Types.ConvertTagDeclType(RD); + return CheckForPointerToDataMember(RD); + } +} - const CGRecordLayout &Layout = Types.getCGRecordLayout(RD); +void +CGRecordLayoutBuilder::CheckForPointerToDataMember(const CXXRecordDecl *RD) { + // This record already contains a member pointer. + if (ContainsPointerToDataMember) + return; - if (Layout.containsPointerToDataMember()) - ContainsPointerToDataMember = true; - } + // FIXME: It would be better if there was a way to explicitly compute the + // record layout instead of converting to a type. + Types.ConvertTagDeclType(RD); + + const CGRecordLayout &Layout = Types.getCGRecordLayout(RD); + + if (Layout.containsPointerToDataMember()) + ContainsPointerToDataMember = true; } CGRecordLayout *CodeGenTypes::ComputeRecordLayout(const RecordDecl *D) { @@ -584,13 +654,17 @@ CGRecordLayout *CodeGenTypes::ComputeRecordLayout(const RecordDecl *D) { CGRecordLayout *RL = new CGRecordLayout(Ty, Builder.ContainsPointerToDataMember); + // Add all the non-virtual base field numbers. + RL->NonVirtualBaseFields.insert(Builder.LLVMNonVirtualBases.begin(), + Builder.LLVMNonVirtualBases.end()); + // Add all the field numbers. - for (unsigned i = 0, e = Builder.LLVMFields.size(); i != e; ++i) - RL->FieldInfo.insert(Builder.LLVMFields[i]); + RL->FieldInfo.insert(Builder.LLVMFields.begin(), + Builder.LLVMFields.end()); // Add bitfield info. - for (unsigned i = 0, e = Builder.LLVMBitFields.size(); i != e; ++i) - RL->BitFields.insert(Builder.LLVMBitFields[i]); + RL->BitFields.insert(Builder.LLVMBitFields.begin(), + Builder.LLVMBitFields.end()); // Dump the layout, if requested. if (getContext().getLangOptions().DumpRecordLayouts) { |