| //===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This provides Objective-C code generation targeting the GNU runtime. The |
| // class in this file generates structures used by the GNU Objective-C runtime |
| // library. These structures are defined in objc/objc.h and objc/objc-api.h in |
| // the GNU runtime distribution. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CGCXXABI.h" |
| #include "CGCleanup.h" |
| #include "CGObjCRuntime.h" |
| #include "CodeGenFunction.h" |
| #include "CodeGenModule.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/Attr.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/RecordLayout.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "clang/Basic/FileManager.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/CodeGen/ConstantInitBuilder.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/IR/Module.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/ConvertUTF.h" |
| #include <cctype> |
| |
| using namespace clang; |
| using namespace CodeGen; |
| |
| namespace { |
| |
| std::string SymbolNameForMethod( StringRef ClassName, |
| StringRef CategoryName, const Selector MethodName, |
| bool isClassMethod) { |
| std::string MethodNameColonStripped = MethodName.getAsString(); |
| std::replace(MethodNameColonStripped.begin(), MethodNameColonStripped.end(), |
| ':', '_'); |
| return (Twine(isClassMethod ? "_c_" : "_i_") + ClassName + "_" + |
| CategoryName + "_" + MethodNameColonStripped).str(); |
| } |
| |
| /// Class that lazily initialises the runtime function. Avoids inserting the |
| /// types and the function declaration into a module if they're not used, and |
| /// avoids constructing the type more than once if it's used more than once. |
| class LazyRuntimeFunction { |
| CodeGenModule *CGM; |
| llvm::FunctionType *FTy; |
| const char *FunctionName; |
| llvm::FunctionCallee Function; |
| |
| public: |
| /// Constructor leaves this class uninitialized, because it is intended to |
| /// be used as a field in another class and not all of the types that are |
| /// used as arguments will necessarily be available at construction time. |
| LazyRuntimeFunction() |
| : CGM(nullptr), FunctionName(nullptr), Function(nullptr) {} |
| |
| /// Initialises the lazy function with the name, return type, and the types |
| /// of the arguments. |
| template <typename... Tys> |
| void init(CodeGenModule *Mod, const char *name, llvm::Type *RetTy, |
| Tys *... Types) { |
| CGM = Mod; |
| FunctionName = name; |
| Function = nullptr; |
| if(sizeof...(Tys)) { |
| SmallVector<llvm::Type *, 8> ArgTys({Types...}); |
| FTy = llvm::FunctionType::get(RetTy, ArgTys, false); |
| } |
| else { |
| FTy = llvm::FunctionType::get(RetTy, None, false); |
| } |
| } |
| |
| llvm::FunctionType *getType() { return FTy; } |
| |
| /// Overloaded cast operator, allows the class to be implicitly cast to an |
| /// LLVM constant. |
| operator llvm::FunctionCallee() { |
| if (!Function) { |
| if (!FunctionName) |
| return nullptr; |
| Function = CGM->CreateRuntimeFunction(FTy, FunctionName); |
| } |
| return Function; |
| } |
| }; |
| |
| |
| /// GNU Objective-C runtime code generation. This class implements the parts of |
| /// Objective-C support that are specific to the GNU family of runtimes (GCC, |
| /// GNUstep and ObjFW). |
| class CGObjCGNU : public CGObjCRuntime { |
| protected: |
| /// The LLVM module into which output is inserted |
| llvm::Module &TheModule; |
| /// strut objc_super. Used for sending messages to super. This structure |
| /// contains the receiver (object) and the expected class. |
| llvm::StructType *ObjCSuperTy; |
| /// struct objc_super*. The type of the argument to the superclass message |
| /// lookup functions. |
| llvm::PointerType *PtrToObjCSuperTy; |
| /// LLVM type for selectors. Opaque pointer (i8*) unless a header declaring |
| /// SEL is included in a header somewhere, in which case it will be whatever |
| /// type is declared in that header, most likely {i8*, i8*}. |
| llvm::PointerType *SelectorTy; |
| /// LLVM i8 type. Cached here to avoid repeatedly getting it in all of the |
| /// places where it's used |
| llvm::IntegerType *Int8Ty; |
| /// Pointer to i8 - LLVM type of char*, for all of the places where the |
| /// runtime needs to deal with C strings. |
| llvm::PointerType *PtrToInt8Ty; |
| /// struct objc_protocol type |
| llvm::StructType *ProtocolTy; |
| /// Protocol * type. |
| llvm::PointerType *ProtocolPtrTy; |
| /// Instance Method Pointer type. This is a pointer to a function that takes, |
| /// at a minimum, an object and a selector, and is the generic type for |
| /// Objective-C methods. Due to differences between variadic / non-variadic |
| /// calling conventions, it must always be cast to the correct type before |
| /// actually being used. |
| llvm::PointerType *IMPTy; |
| /// Type of an untyped Objective-C object. Clang treats id as a built-in type |
| /// when compiling Objective-C code, so this may be an opaque pointer (i8*), |
| /// but if the runtime header declaring it is included then it may be a |
| /// pointer to a structure. |
| llvm::PointerType *IdTy; |
| /// Pointer to a pointer to an Objective-C object. Used in the new ABI |
| /// message lookup function and some GC-related functions. |
| llvm::PointerType *PtrToIdTy; |
| /// The clang type of id. Used when using the clang CGCall infrastructure to |
| /// call Objective-C methods. |
| CanQualType ASTIdTy; |
| /// LLVM type for C int type. |
| llvm::IntegerType *IntTy; |
| /// LLVM type for an opaque pointer. This is identical to PtrToInt8Ty, but is |
| /// used in the code to document the difference between i8* meaning a pointer |
| /// to a C string and i8* meaning a pointer to some opaque type. |
| llvm::PointerType *PtrTy; |
| /// LLVM type for C long type. The runtime uses this in a lot of places where |
| /// it should be using intptr_t, but we can't fix this without breaking |
| /// compatibility with GCC... |
| llvm::IntegerType *LongTy; |
| /// LLVM type for C size_t. Used in various runtime data structures. |
| llvm::IntegerType *SizeTy; |
| /// LLVM type for C intptr_t. |
| llvm::IntegerType *IntPtrTy; |
| /// LLVM type for C ptrdiff_t. Mainly used in property accessor functions. |
| llvm::IntegerType *PtrDiffTy; |
| /// LLVM type for C int*. Used for GCC-ABI-compatible non-fragile instance |
| /// variables. |
| llvm::PointerType *PtrToIntTy; |
| /// LLVM type for Objective-C BOOL type. |
| llvm::Type *BoolTy; |
| /// 32-bit integer type, to save us needing to look it up every time it's used. |
| llvm::IntegerType *Int32Ty; |
| /// 64-bit integer type, to save us needing to look it up every time it's used. |
| llvm::IntegerType *Int64Ty; |
| /// The type of struct objc_property. |
| llvm::StructType *PropertyMetadataTy; |
| /// Metadata kind used to tie method lookups to message sends. The GNUstep |
| /// runtime provides some LLVM passes that can use this to do things like |
| /// automatic IMP caching and speculative inlining. |
| unsigned msgSendMDKind; |
| /// Does the current target use SEH-based exceptions? False implies |
| /// Itanium-style DWARF unwinding. |
| bool usesSEHExceptions; |
| |
| /// Helper to check if we are targeting a specific runtime version or later. |
| bool isRuntime(ObjCRuntime::Kind kind, unsigned major, unsigned minor=0) { |
| const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime; |
| return (R.getKind() == kind) && |
| (R.getVersion() >= VersionTuple(major, minor)); |
| } |
| |
| std::string ManglePublicSymbol(StringRef Name) { |
| return (StringRef(CGM.getTriple().isOSBinFormatCOFF() ? "$_" : "._") + Name).str(); |
| } |
| |
| std::string SymbolForProtocol(Twine Name) { |
| return (ManglePublicSymbol("OBJC_PROTOCOL_") + Name).str(); |
| } |
| |
| std::string SymbolForProtocolRef(StringRef Name) { |
| return (ManglePublicSymbol("OBJC_REF_PROTOCOL_") + Name).str(); |
| } |
| |
| |
| /// Helper function that generates a constant string and returns a pointer to |
| /// the start of the string. The result of this function can be used anywhere |
| /// where the C code specifies const char*. |
| llvm::Constant *MakeConstantString(StringRef Str, const char *Name = "") { |
| ConstantAddress Array = |
| CGM.GetAddrOfConstantCString(std::string(Str), Name); |
| return llvm::ConstantExpr::getGetElementPtr(Array.getElementType(), |
| Array.getPointer(), Zeros); |
| } |
| |
| /// Emits a linkonce_odr string, whose name is the prefix followed by the |
| /// string value. This allows the linker to combine the strings between |
| /// different modules. Used for EH typeinfo names, selector strings, and a |
| /// few other things. |
| llvm::Constant *ExportUniqueString(const std::string &Str, |
| const std::string &prefix, |
| bool Private=false) { |
| std::string name = prefix + Str; |
| auto *ConstStr = TheModule.getGlobalVariable(name); |
| if (!ConstStr) { |
| llvm::Constant *value = llvm::ConstantDataArray::getString(VMContext,Str); |
| auto *GV = new llvm::GlobalVariable(TheModule, value->getType(), true, |
| llvm::GlobalValue::LinkOnceODRLinkage, value, name); |
| GV->setComdat(TheModule.getOrInsertComdat(name)); |
| if (Private) |
| GV->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| ConstStr = GV; |
| } |
| return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(), |
| ConstStr, Zeros); |
| } |
| |
| /// Returns a property name and encoding string. |
| llvm::Constant *MakePropertyEncodingString(const ObjCPropertyDecl *PD, |
| const Decl *Container) { |
| assert(!isRuntime(ObjCRuntime::GNUstep, 2)); |
| if (isRuntime(ObjCRuntime::GNUstep, 1, 6)) { |
| std::string NameAndAttributes; |
| std::string TypeStr = |
| CGM.getContext().getObjCEncodingForPropertyDecl(PD, Container); |
| NameAndAttributes += '\0'; |
| NameAndAttributes += TypeStr.length() + 3; |
| NameAndAttributes += TypeStr; |
| NameAndAttributes += '\0'; |
| NameAndAttributes += PD->getNameAsString(); |
| return MakeConstantString(NameAndAttributes); |
| } |
| return MakeConstantString(PD->getNameAsString()); |
| } |
| |
| /// Push the property attributes into two structure fields. |
| void PushPropertyAttributes(ConstantStructBuilder &Fields, |
| const ObjCPropertyDecl *property, bool isSynthesized=true, bool |
| isDynamic=true) { |
| int attrs = property->getPropertyAttributes(); |
| // For read-only properties, clear the copy and retain flags |
| if (attrs & ObjCPropertyAttribute::kind_readonly) { |
| attrs &= ~ObjCPropertyAttribute::kind_copy; |
| attrs &= ~ObjCPropertyAttribute::kind_retain; |
| attrs &= ~ObjCPropertyAttribute::kind_weak; |
| attrs &= ~ObjCPropertyAttribute::kind_strong; |
| } |
| // The first flags field has the same attribute values as clang uses internally |
| Fields.addInt(Int8Ty, attrs & 0xff); |
| attrs >>= 8; |
| attrs <<= 2; |
| // For protocol properties, synthesized and dynamic have no meaning, so we |
| // reuse these flags to indicate that this is a protocol property (both set |
| // has no meaning, as a property can't be both synthesized and dynamic) |
| attrs |= isSynthesized ? (1<<0) : 0; |
| attrs |= isDynamic ? (1<<1) : 0; |
| // The second field is the next four fields left shifted by two, with the |
| // low bit set to indicate whether the field is synthesized or dynamic. |
| Fields.addInt(Int8Ty, attrs & 0xff); |
| // Two padding fields |
| Fields.addInt(Int8Ty, 0); |
| Fields.addInt(Int8Ty, 0); |
| } |
| |
| virtual llvm::Constant *GenerateCategoryProtocolList(const |
| ObjCCategoryDecl *OCD); |
| virtual ConstantArrayBuilder PushPropertyListHeader(ConstantStructBuilder &Fields, |
| int count) { |
| // int count; |
| Fields.addInt(IntTy, count); |
| // int size; (only in GNUstep v2 ABI. |
| if (isRuntime(ObjCRuntime::GNUstep, 2)) { |
| llvm::DataLayout td(&TheModule); |
| Fields.addInt(IntTy, td.getTypeSizeInBits(PropertyMetadataTy) / |
| CGM.getContext().getCharWidth()); |
| } |
| // struct objc_property_list *next; |
| Fields.add(NULLPtr); |
| // struct objc_property properties[] |
| return Fields.beginArray(PropertyMetadataTy); |
| } |
| virtual void PushProperty(ConstantArrayBuilder &PropertiesArray, |
| const ObjCPropertyDecl *property, |
| const Decl *OCD, |
| bool isSynthesized=true, bool |
| isDynamic=true) { |
| auto Fields = PropertiesArray.beginStruct(PropertyMetadataTy); |
| ASTContext &Context = CGM.getContext(); |
| Fields.add(MakePropertyEncodingString(property, OCD)); |
| PushPropertyAttributes(Fields, property, isSynthesized, isDynamic); |
| auto addPropertyMethod = [&](const ObjCMethodDecl *accessor) { |
| if (accessor) { |
| std::string TypeStr = Context.getObjCEncodingForMethodDecl(accessor); |
| llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); |
| Fields.add(MakeConstantString(accessor->getSelector().getAsString())); |
| Fields.add(TypeEncoding); |
| } else { |
| Fields.add(NULLPtr); |
| Fields.add(NULLPtr); |
| } |
| }; |
| addPropertyMethod(property->getGetterMethodDecl()); |
| addPropertyMethod(property->getSetterMethodDecl()); |
| Fields.finishAndAddTo(PropertiesArray); |
| } |
| |
| /// Ensures that the value has the required type, by inserting a bitcast if |
| /// required. This function lets us avoid inserting bitcasts that are |
| /// redundant. |
| llvm::Value* EnforceType(CGBuilderTy &B, llvm::Value *V, llvm::Type *Ty) { |
| if (V->getType() == Ty) return V; |
| return B.CreateBitCast(V, Ty); |
| } |
| Address EnforceType(CGBuilderTy &B, Address V, llvm::Type *Ty) { |
| if (V.getType() == Ty) return V; |
| return B.CreateBitCast(V, Ty); |
| } |
| |
| // Some zeros used for GEPs in lots of places. |
| llvm::Constant *Zeros[2]; |
| /// Null pointer value. Mainly used as a terminator in various arrays. |
| llvm::Constant *NULLPtr; |
| /// LLVM context. |
| llvm::LLVMContext &VMContext; |
| |
| protected: |
| |
| /// Placeholder for the class. Lots of things refer to the class before we've |
| /// actually emitted it. We use this alias as a placeholder, and then replace |
| /// it with a pointer to the class structure before finally emitting the |
| /// module. |
| llvm::GlobalAlias *ClassPtrAlias; |
| /// Placeholder for the metaclass. Lots of things refer to the class before |
| /// we've / actually emitted it. We use this alias as a placeholder, and then |
| /// replace / it with a pointer to the metaclass structure before finally |
| /// emitting the / module. |
| llvm::GlobalAlias *MetaClassPtrAlias; |
| /// All of the classes that have been generated for this compilation units. |
| std::vector<llvm::Constant*> Classes; |
| /// All of the categories that have been generated for this compilation units. |
| std::vector<llvm::Constant*> Categories; |
| /// All of the Objective-C constant strings that have been generated for this |
| /// compilation units. |
| std::vector<llvm::Constant*> ConstantStrings; |
| /// Map from string values to Objective-C constant strings in the output. |
| /// Used to prevent emitting Objective-C strings more than once. This should |
| /// not be required at all - CodeGenModule should manage this list. |
| llvm::StringMap<llvm::Constant*> ObjCStrings; |
| /// All of the protocols that have been declared. |
| llvm::StringMap<llvm::Constant*> ExistingProtocols; |
| /// For each variant of a selector, we store the type encoding and a |
| /// placeholder value. For an untyped selector, the type will be the empty |
| /// string. Selector references are all done via the module's selector table, |
| /// so we create an alias as a placeholder and then replace it with the real |
| /// value later. |
| typedef std::pair<std::string, llvm::GlobalAlias*> TypedSelector; |
| /// Type of the selector map. This is roughly equivalent to the structure |
| /// used in the GNUstep runtime, which maintains a list of all of the valid |
| /// types for a selector in a table. |
| typedef llvm::DenseMap<Selector, SmallVector<TypedSelector, 2> > |
| SelectorMap; |
| /// A map from selectors to selector types. This allows us to emit all |
| /// selectors of the same name and type together. |
| SelectorMap SelectorTable; |
| |
| /// Selectors related to memory management. When compiling in GC mode, we |
| /// omit these. |
| Selector RetainSel, ReleaseSel, AutoreleaseSel; |
| /// Runtime functions used for memory management in GC mode. Note that clang |
| /// supports code generation for calling these functions, but neither GNU |
| /// runtime actually supports this API properly yet. |
| LazyRuntimeFunction IvarAssignFn, StrongCastAssignFn, MemMoveFn, WeakReadFn, |
| WeakAssignFn, GlobalAssignFn; |
| |
| typedef std::pair<std::string, std::string> ClassAliasPair; |
| /// All classes that have aliases set for them. |
| std::vector<ClassAliasPair> ClassAliases; |
| |
| protected: |
| /// Function used for throwing Objective-C exceptions. |
| LazyRuntimeFunction ExceptionThrowFn; |
| /// Function used for rethrowing exceptions, used at the end of \@finally or |
| /// \@synchronize blocks. |
| LazyRuntimeFunction ExceptionReThrowFn; |
| /// Function called when entering a catch function. This is required for |
| /// differentiating Objective-C exceptions and foreign exceptions. |
| LazyRuntimeFunction EnterCatchFn; |
| /// Function called when exiting from a catch block. Used to do exception |
| /// cleanup. |
| LazyRuntimeFunction ExitCatchFn; |
| /// Function called when entering an \@synchronize block. Acquires the lock. |
| LazyRuntimeFunction SyncEnterFn; |
| /// Function called when exiting an \@synchronize block. Releases the lock. |
| LazyRuntimeFunction SyncExitFn; |
| |
| private: |
| /// Function called if fast enumeration detects that the collection is |
| /// modified during the update. |
| LazyRuntimeFunction EnumerationMutationFn; |
| /// Function for implementing synthesized property getters that return an |
| /// object. |
| LazyRuntimeFunction GetPropertyFn; |
| /// Function for implementing synthesized property setters that return an |
| /// object. |
| LazyRuntimeFunction SetPropertyFn; |
| /// Function used for non-object declared property getters. |
| LazyRuntimeFunction GetStructPropertyFn; |
| /// Function used for non-object declared property setters. |
| LazyRuntimeFunction SetStructPropertyFn; |
| |
| protected: |
| /// The version of the runtime that this class targets. Must match the |
| /// version in the runtime. |
| int RuntimeVersion; |
| /// The version of the protocol class. Used to differentiate between ObjC1 |
| /// and ObjC2 protocols. Objective-C 1 protocols can not contain optional |
| /// components and can not contain declared properties. We always emit |
| /// Objective-C 2 property structures, but we have to pretend that they're |
| /// Objective-C 1 property structures when targeting the GCC runtime or it |
| /// will abort. |
| const int ProtocolVersion; |
| /// The version of the class ABI. This value is used in the class structure |
| /// and indicates how various fields should be interpreted. |
| const int ClassABIVersion; |
| /// Generates an instance variable list structure. This is a structure |
| /// containing a size and an array of structures containing instance variable |
| /// metadata. This is used purely for introspection in the fragile ABI. In |
| /// the non-fragile ABI, it's used for instance variable fixup. |
| virtual llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames, |
| ArrayRef<llvm::Constant *> IvarTypes, |
| ArrayRef<llvm::Constant *> IvarOffsets, |
| ArrayRef<llvm::Constant *> IvarAlign, |
| ArrayRef<Qualifiers::ObjCLifetime> IvarOwnership); |
| |
| /// Generates a method list structure. This is a structure containing a size |
| /// and an array of structures containing method metadata. |
| /// |
| /// This structure is used by both classes and categories, and contains a next |
| /// pointer allowing them to be chained together in a linked list. |
| llvm::Constant *GenerateMethodList(StringRef ClassName, |
| StringRef CategoryName, |
| ArrayRef<const ObjCMethodDecl*> Methods, |
| bool isClassMethodList); |
| |
| /// Emits an empty protocol. This is used for \@protocol() where no protocol |
| /// is found. The runtime will (hopefully) fix up the pointer to refer to the |
| /// real protocol. |
| virtual llvm::Constant *GenerateEmptyProtocol(StringRef ProtocolName); |
| |
| /// Generates a list of property metadata structures. This follows the same |
| /// pattern as method and instance variable metadata lists. |
| llvm::Constant *GeneratePropertyList(const Decl *Container, |
| const ObjCContainerDecl *OCD, |
| bool isClassProperty=false, |
| bool protocolOptionalProperties=false); |
| |
| /// Generates a list of referenced protocols. Classes, categories, and |
| /// protocols all use this structure. |
| llvm::Constant *GenerateProtocolList(ArrayRef<std::string> Protocols); |
| |
| /// To ensure that all protocols are seen by the runtime, we add a category on |
| /// a class defined in the runtime, declaring no methods, but adopting the |
| /// protocols. This is a horribly ugly hack, but it allows us to collect all |
| /// of the protocols without changing the ABI. |
| void GenerateProtocolHolderCategory(); |
| |
| /// Generates a class structure. |
| llvm::Constant *GenerateClassStructure( |
| llvm::Constant *MetaClass, |
| llvm::Constant *SuperClass, |
| unsigned info, |
| const char *Name, |
| llvm::Constant *Version, |
| llvm::Constant *InstanceSize, |
| llvm::Constant *IVars, |
| llvm::Constant *Methods, |
| llvm::Constant *Protocols, |
| llvm::Constant *IvarOffsets, |
| llvm::Constant *Properties, |
| llvm::Constant *StrongIvarBitmap, |
| llvm::Constant *WeakIvarBitmap, |
| bool isMeta=false); |
| |
| /// Generates a method list. This is used by protocols to define the required |
| /// and optional methods. |
| virtual llvm::Constant *GenerateProtocolMethodList( |
| ArrayRef<const ObjCMethodDecl*> Methods); |
| /// Emits optional and required method lists. |
| template<class T> |
| void EmitProtocolMethodList(T &&Methods, llvm::Constant *&Required, |
| llvm::Constant *&Optional) { |
| SmallVector<const ObjCMethodDecl*, 16> RequiredMethods; |
| SmallVector<const ObjCMethodDecl*, 16> OptionalMethods; |
| for (const auto *I : Methods) |
| if (I->isOptional()) |
| OptionalMethods.push_back(I); |
| else |
| RequiredMethods.push_back(I); |
| Required = GenerateProtocolMethodList(RequiredMethods); |
| Optional = GenerateProtocolMethodList(OptionalMethods); |
| } |
| |
| /// Returns a selector with the specified type encoding. An empty string is |
| /// used to return an untyped selector (with the types field set to NULL). |
| virtual llvm::Value *GetTypedSelector(CodeGenFunction &CGF, Selector Sel, |
| const std::string &TypeEncoding); |
| |
| /// Returns the name of ivar offset variables. In the GNUstep v1 ABI, this |
| /// contains the class and ivar names, in the v2 ABI this contains the type |
| /// encoding as well. |
| virtual std::string GetIVarOffsetVariableName(const ObjCInterfaceDecl *ID, |
| const ObjCIvarDecl *Ivar) { |
| const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString() |
| + '.' + Ivar->getNameAsString(); |
| return Name; |
| } |
| /// Returns the variable used to store the offset of an instance variable. |
| llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID, |
| const ObjCIvarDecl *Ivar); |
| /// Emits a reference to a class. This allows the linker to object if there |
| /// is no class of the matching name. |
| void EmitClassRef(const std::string &className); |
| |
| /// Emits a pointer to the named class |
| virtual llvm::Value *GetClassNamed(CodeGenFunction &CGF, |
| const std::string &Name, bool isWeak); |
| |
| /// Looks up the method for sending a message to the specified object. This |
| /// mechanism differs between the GCC and GNU runtimes, so this method must be |
| /// overridden in subclasses. |
| virtual llvm::Value *LookupIMP(CodeGenFunction &CGF, |
| llvm::Value *&Receiver, |
| llvm::Value *cmd, |
| llvm::MDNode *node, |
| MessageSendInfo &MSI) = 0; |
| |
| /// Looks up the method for sending a message to a superclass. This |
| /// mechanism differs between the GCC and GNU runtimes, so this method must |
| /// be overridden in subclasses. |
| virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, |
| Address ObjCSuper, |
| llvm::Value *cmd, |
| MessageSendInfo &MSI) = 0; |
| |
| /// Libobjc2 uses a bitfield representation where small(ish) bitfields are |
| /// stored in a 64-bit value with the low bit set to 1 and the remaining 63 |
| /// bits set to their values, LSB first, while larger ones are stored in a |
| /// structure of this / form: |
| /// |
| /// struct { int32_t length; int32_t values[length]; }; |
| /// |
| /// The values in the array are stored in host-endian format, with the least |
| /// significant bit being assumed to come first in the bitfield. Therefore, |
| /// a bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] }, |
| /// while a bitfield / with the 63rd bit set will be 1<<64. |
| llvm::Constant *MakeBitField(ArrayRef<bool> bits); |
| |
| public: |
| CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion, |
| unsigned protocolClassVersion, unsigned classABI=1); |
| |
| ConstantAddress GenerateConstantString(const StringLiteral *) override; |
| |
| RValue |
| GenerateMessageSend(CodeGenFunction &CGF, ReturnValueSlot Return, |
| QualType ResultType, Selector Sel, |
| llvm::Value *Receiver, const CallArgList &CallArgs, |
| const ObjCInterfaceDecl *Class, |
| const ObjCMethodDecl *Method) override; |
| RValue |
| GenerateMessageSendSuper(CodeGenFunction &CGF, ReturnValueSlot Return, |
| QualType ResultType, Selector Sel, |
| const ObjCInterfaceDecl *Class, |
| bool isCategoryImpl, llvm::Value *Receiver, |
| bool IsClassMessage, const CallArgList &CallArgs, |
| const ObjCMethodDecl *Method) override; |
| llvm::Value *GetClass(CodeGenFunction &CGF, |
| const ObjCInterfaceDecl *OID) override; |
| llvm::Value *GetSelector(CodeGenFunction &CGF, Selector Sel) override; |
| Address GetAddrOfSelector(CodeGenFunction &CGF, Selector Sel) override; |
| llvm::Value *GetSelector(CodeGenFunction &CGF, |
| const ObjCMethodDecl *Method) override; |
| virtual llvm::Constant *GetConstantSelector(Selector Sel, |
| const std::string &TypeEncoding) { |
| llvm_unreachable("Runtime unable to generate constant selector"); |
| } |
| llvm::Constant *GetConstantSelector(const ObjCMethodDecl *M) { |
| return GetConstantSelector(M->getSelector(), |
| CGM.getContext().getObjCEncodingForMethodDecl(M)); |
| } |
| llvm::Constant *GetEHType(QualType T) override; |
| |
| llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD, |
| const ObjCContainerDecl *CD) override; |
| void GenerateDirectMethodPrologue(CodeGenFunction &CGF, llvm::Function *Fn, |
| const ObjCMethodDecl *OMD, |
| const ObjCContainerDecl *CD) override; |
| void GenerateCategory(const ObjCCategoryImplDecl *CMD) override; |
| void GenerateClass(const ObjCImplementationDecl *ClassDecl) override; |
| void RegisterAlias(const ObjCCompatibleAliasDecl *OAD) override; |
| llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF, |
| const ObjCProtocolDecl *PD) override; |
| void GenerateProtocol(const ObjCProtocolDecl *PD) override; |
| |
| virtual llvm::Constant *GenerateProtocolRef(const ObjCProtocolDecl *PD); |
| |
| llvm::Constant *GetOrEmitProtocol(const ObjCProtocolDecl *PD) override { |
| return GenerateProtocolRef(PD); |
| } |
| |
| llvm::Function *ModuleInitFunction() override; |
| llvm::FunctionCallee GetPropertyGetFunction() override; |
| llvm::FunctionCallee GetPropertySetFunction() override; |
| llvm::FunctionCallee GetOptimizedPropertySetFunction(bool atomic, |
| bool copy) override; |
| llvm::FunctionCallee GetSetStructFunction() override; |
| llvm::FunctionCallee GetGetStructFunction() override; |
| llvm::FunctionCallee GetCppAtomicObjectGetFunction() override; |
| llvm::FunctionCallee GetCppAtomicObjectSetFunction() override; |
| llvm::FunctionCallee EnumerationMutationFunction() override; |
| |
| void EmitTryStmt(CodeGenFunction &CGF, |
| const ObjCAtTryStmt &S) override; |
| void EmitSynchronizedStmt(CodeGenFunction &CGF, |
| const ObjCAtSynchronizedStmt &S) override; |
| void EmitThrowStmt(CodeGenFunction &CGF, |
| const ObjCAtThrowStmt &S, |
| bool ClearInsertionPoint=true) override; |
| llvm::Value * EmitObjCWeakRead(CodeGenFunction &CGF, |
| Address AddrWeakObj) override; |
| void EmitObjCWeakAssign(CodeGenFunction &CGF, |
| llvm::Value *src, Address dst) override; |
| void EmitObjCGlobalAssign(CodeGenFunction &CGF, |
| llvm::Value *src, Address dest, |
| bool threadlocal=false) override; |
| void EmitObjCIvarAssign(CodeGenFunction &CGF, llvm::Value *src, |
| Address dest, llvm::Value *ivarOffset) override; |
| void EmitObjCStrongCastAssign(CodeGenFunction &CGF, |
| llvm::Value *src, Address dest) override; |
| void EmitGCMemmoveCollectable(CodeGenFunction &CGF, Address DestPtr, |
| Address SrcPtr, |
| llvm::Value *Size) override; |
| LValue EmitObjCValueForIvar(CodeGenFunction &CGF, QualType ObjectTy, |
| llvm::Value *BaseValue, const ObjCIvarDecl *Ivar, |
| unsigned CVRQualifiers) override; |
| llvm::Value *EmitIvarOffset(CodeGenFunction &CGF, |
| const ObjCInterfaceDecl *Interface, |
| const ObjCIvarDecl *Ivar) override; |
| llvm::Value *EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) override; |
| llvm::Constant *BuildGCBlockLayout(CodeGenModule &CGM, |
| const CGBlockInfo &blockInfo) override { |
| return NULLPtr; |
| } |
| llvm::Constant *BuildRCBlockLayout(CodeGenModule &CGM, |
| const CGBlockInfo &blockInfo) override { |
| return NULLPtr; |
| } |
| |
| llvm::Constant *BuildByrefLayout(CodeGenModule &CGM, QualType T) override { |
| return NULLPtr; |
| } |
| }; |
| |
| /// Class representing the legacy GCC Objective-C ABI. This is the default when |
| /// -fobjc-nonfragile-abi is not specified. |
| /// |
| /// The GCC ABI target actually generates code that is approximately compatible |
| /// with the new GNUstep runtime ABI, but refrains from using any features that |
| /// would not work with the GCC runtime. For example, clang always generates |
| /// the extended form of the class structure, and the extra fields are simply |
| /// ignored by GCC libobjc. |
| class CGObjCGCC : public CGObjCGNU { |
| /// The GCC ABI message lookup function. Returns an IMP pointing to the |
| /// method implementation for this message. |
| LazyRuntimeFunction MsgLookupFn; |
| /// The GCC ABI superclass message lookup function. Takes a pointer to a |
| /// structure describing the receiver and the class, and a selector as |
| /// arguments. Returns the IMP for the corresponding method. |
| LazyRuntimeFunction MsgLookupSuperFn; |
| |
| protected: |
| llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver, |
| llvm::Value *cmd, llvm::MDNode *node, |
| MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *args[] = { |
| EnforceType(Builder, Receiver, IdTy), |
| EnforceType(Builder, cmd, SelectorTy) }; |
| llvm::CallBase *imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args); |
| imp->setMetadata(msgSendMDKind, node); |
| return imp; |
| } |
| |
| llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper, |
| llvm::Value *cmd, MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper, |
| PtrToObjCSuperTy).getPointer(), cmd}; |
| return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs); |
| } |
| |
| public: |
| CGObjCGCC(CodeGenModule &Mod) : CGObjCGNU(Mod, 8, 2) { |
| // IMP objc_msg_lookup(id, SEL); |
| MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy); |
| // IMP objc_msg_lookup_super(struct objc_super*, SEL); |
| MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy, |
| PtrToObjCSuperTy, SelectorTy); |
| } |
| }; |
| |
| /// Class used when targeting the new GNUstep runtime ABI. |
| class CGObjCGNUstep : public CGObjCGNU { |
| /// The slot lookup function. Returns a pointer to a cacheable structure |
| /// that contains (among other things) the IMP. |
| LazyRuntimeFunction SlotLookupFn; |
| /// The GNUstep ABI superclass message lookup function. Takes a pointer to |
| /// a structure describing the receiver and the class, and a selector as |
| /// arguments. Returns the slot for the corresponding method. Superclass |
| /// message lookup rarely changes, so this is a good caching opportunity. |
| LazyRuntimeFunction SlotLookupSuperFn; |
| /// Specialised function for setting atomic retain properties |
| LazyRuntimeFunction SetPropertyAtomic; |
| /// Specialised function for setting atomic copy properties |
| LazyRuntimeFunction SetPropertyAtomicCopy; |
| /// Specialised function for setting nonatomic retain properties |
| LazyRuntimeFunction SetPropertyNonAtomic; |
| /// Specialised function for setting nonatomic copy properties |
| LazyRuntimeFunction SetPropertyNonAtomicCopy; |
| /// Function to perform atomic copies of C++ objects with nontrivial copy |
| /// constructors from Objective-C ivars. |
| LazyRuntimeFunction CxxAtomicObjectGetFn; |
| /// Function to perform atomic copies of C++ objects with nontrivial copy |
| /// constructors to Objective-C ivars. |
| LazyRuntimeFunction CxxAtomicObjectSetFn; |
| /// Type of an slot structure pointer. This is returned by the various |
| /// lookup functions. |
| llvm::Type *SlotTy; |
| |
| public: |
| llvm::Constant *GetEHType(QualType T) override; |
| |
| protected: |
| llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver, |
| llvm::Value *cmd, llvm::MDNode *node, |
| MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::FunctionCallee LookupFn = SlotLookupFn; |
| |
| // Store the receiver on the stack so that we can reload it later |
| Address ReceiverPtr = |
| CGF.CreateTempAlloca(Receiver->getType(), CGF.getPointerAlign()); |
| Builder.CreateStore(Receiver, ReceiverPtr); |
| |
| llvm::Value *self; |
| |
| if (isa<ObjCMethodDecl>(CGF.CurCodeDecl)) { |
| self = CGF.LoadObjCSelf(); |
| } else { |
| self = llvm::ConstantPointerNull::get(IdTy); |
| } |
| |
| // The lookup function is guaranteed not to capture the receiver pointer. |
| if (auto *LookupFn2 = dyn_cast<llvm::Function>(LookupFn.getCallee())) |
| LookupFn2->addParamAttr(0, llvm::Attribute::NoCapture); |
| |
| llvm::Value *args[] = { |
| EnforceType(Builder, ReceiverPtr.getPointer(), PtrToIdTy), |
| EnforceType(Builder, cmd, SelectorTy), |
| EnforceType(Builder, self, IdTy) }; |
| llvm::CallBase *slot = CGF.EmitRuntimeCallOrInvoke(LookupFn, args); |
| slot->setOnlyReadsMemory(); |
| slot->setMetadata(msgSendMDKind, node); |
| |
| // Load the imp from the slot |
| llvm::Value *imp = Builder.CreateAlignedLoad( |
| Builder.CreateStructGEP(nullptr, slot, 4), CGF.getPointerAlign()); |
| |
| // The lookup function may have changed the receiver, so make sure we use |
| // the new one. |
| Receiver = Builder.CreateLoad(ReceiverPtr, true); |
| return imp; |
| } |
| |
| llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper, |
| llvm::Value *cmd, |
| MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *lookupArgs[] = {ObjCSuper.getPointer(), cmd}; |
| |
| llvm::CallInst *slot = |
| CGF.EmitNounwindRuntimeCall(SlotLookupSuperFn, lookupArgs); |
| slot->setOnlyReadsMemory(); |
| |
| return Builder.CreateAlignedLoad(Builder.CreateStructGEP(nullptr, slot, 4), |
| CGF.getPointerAlign()); |
| } |
| |
| public: |
| CGObjCGNUstep(CodeGenModule &Mod) : CGObjCGNUstep(Mod, 9, 3, 1) {} |
| CGObjCGNUstep(CodeGenModule &Mod, unsigned ABI, unsigned ProtocolABI, |
| unsigned ClassABI) : |
| CGObjCGNU(Mod, ABI, ProtocolABI, ClassABI) { |
| const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime; |
| |
| llvm::StructType *SlotStructTy = |
| llvm::StructType::get(PtrTy, PtrTy, PtrTy, IntTy, IMPTy); |
| SlotTy = llvm::PointerType::getUnqual(SlotStructTy); |
| // Slot_t objc_msg_lookup_sender(id *receiver, SEL selector, id sender); |
| SlotLookupFn.init(&CGM, "objc_msg_lookup_sender", SlotTy, PtrToIdTy, |
| SelectorTy, IdTy); |
| // Slot_t objc_slot_lookup_super(struct objc_super*, SEL); |
| SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy, |
| PtrToObjCSuperTy, SelectorTy); |
| // If we're in ObjC++ mode, then we want to make |
| if (usesSEHExceptions) { |
| llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext); |
| // void objc_exception_rethrow(void) |
| ExceptionReThrowFn.init(&CGM, "objc_exception_rethrow", VoidTy); |
| } else if (CGM.getLangOpts().CPlusPlus) { |
| llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext); |
| // void *__cxa_begin_catch(void *e) |
| EnterCatchFn.init(&CGM, "__cxa_begin_catch", PtrTy, PtrTy); |
| // void __cxa_end_catch(void) |
| ExitCatchFn.init(&CGM, "__cxa_end_catch", VoidTy); |
| // void _Unwind_Resume_or_Rethrow(void*) |
| ExceptionReThrowFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy, |
| PtrTy); |
| } else if (R.getVersion() >= VersionTuple(1, 7)) { |
| llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext); |
| // id objc_begin_catch(void *e) |
| EnterCatchFn.init(&CGM, "objc_begin_catch", IdTy, PtrTy); |
| // void objc_end_catch(void) |
| ExitCatchFn.init(&CGM, "objc_end_catch", VoidTy); |
| // void _Unwind_Resume_or_Rethrow(void*) |
| ExceptionReThrowFn.init(&CGM, "objc_exception_rethrow", VoidTy, PtrTy); |
| } |
| llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext); |
| SetPropertyAtomic.init(&CGM, "objc_setProperty_atomic", VoidTy, IdTy, |
| SelectorTy, IdTy, PtrDiffTy); |
| SetPropertyAtomicCopy.init(&CGM, "objc_setProperty_atomic_copy", VoidTy, |
| IdTy, SelectorTy, IdTy, PtrDiffTy); |
| SetPropertyNonAtomic.init(&CGM, "objc_setProperty_nonatomic", VoidTy, |
| IdTy, SelectorTy, IdTy, PtrDiffTy); |
| SetPropertyNonAtomicCopy.init(&CGM, "objc_setProperty_nonatomic_copy", |
| VoidTy, IdTy, SelectorTy, IdTy, PtrDiffTy); |
| // void objc_setCppObjectAtomic(void *dest, const void *src, void |
| // *helper); |
| CxxAtomicObjectSetFn.init(&CGM, "objc_setCppObjectAtomic", VoidTy, PtrTy, |
| PtrTy, PtrTy); |
| // void objc_getCppObjectAtomic(void *dest, const void *src, void |
| // *helper); |
| CxxAtomicObjectGetFn.init(&CGM, "objc_getCppObjectAtomic", VoidTy, PtrTy, |
| PtrTy, PtrTy); |
| } |
| |
| llvm::FunctionCallee GetCppAtomicObjectGetFunction() override { |
| // The optimised functions were added in version 1.7 of the GNUstep |
| // runtime. |
| assert (CGM.getLangOpts().ObjCRuntime.getVersion() >= |
| VersionTuple(1, 7)); |
| return CxxAtomicObjectGetFn; |
| } |
| |
| llvm::FunctionCallee GetCppAtomicObjectSetFunction() override { |
| // The optimised functions were added in version 1.7 of the GNUstep |
| // runtime. |
| assert (CGM.getLangOpts().ObjCRuntime.getVersion() >= |
| VersionTuple(1, 7)); |
| return CxxAtomicObjectSetFn; |
| } |
| |
| llvm::FunctionCallee GetOptimizedPropertySetFunction(bool atomic, |
| bool copy) override { |
| // The optimised property functions omit the GC check, and so are not |
| // safe to use in GC mode. The standard functions are fast in GC mode, |
| // so there is less advantage in using them. |
| assert ((CGM.getLangOpts().getGC() == LangOptions::NonGC)); |
| // The optimised functions were added in version 1.7 of the GNUstep |
| // runtime. |
| assert (CGM.getLangOpts().ObjCRuntime.getVersion() >= |
| VersionTuple(1, 7)); |
| |
| if (atomic) { |
| if (copy) return SetPropertyAtomicCopy; |
| return SetPropertyAtomic; |
| } |
| |
| return copy ? SetPropertyNonAtomicCopy : SetPropertyNonAtomic; |
| } |
| }; |
| |
| /// GNUstep Objective-C ABI version 2 implementation. |
| /// This is the ABI that provides a clean break with the legacy GCC ABI and |
| /// cleans up a number of things that were added to work around 1980s linkers. |
| class CGObjCGNUstep2 : public CGObjCGNUstep { |
| enum SectionKind |
| { |
| SelectorSection = 0, |
| ClassSection, |
| ClassReferenceSection, |
| CategorySection, |
| ProtocolSection, |
| ProtocolReferenceSection, |
| ClassAliasSection, |
| ConstantStringSection |
| }; |
| static const char *const SectionsBaseNames[8]; |
| static const char *const PECOFFSectionsBaseNames[8]; |
| template<SectionKind K> |
| std::string sectionName() { |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| std::string name(PECOFFSectionsBaseNames[K]); |
| name += "$m"; |
| return name; |
| } |
| return SectionsBaseNames[K]; |
| } |
| /// The GCC ABI superclass message lookup function. Takes a pointer to a |
| /// structure describing the receiver and the class, and a selector as |
| /// arguments. Returns the IMP for the corresponding method. |
| LazyRuntimeFunction MsgLookupSuperFn; |
| /// A flag indicating if we've emitted at least one protocol. |
| /// If we haven't, then we need to emit an empty protocol, to ensure that the |
| /// __start__objc_protocols and __stop__objc_protocols sections exist. |
| bool EmittedProtocol = false; |
| /// A flag indicating if we've emitted at least one protocol reference. |
| /// If we haven't, then we need to emit an empty protocol, to ensure that the |
| /// __start__objc_protocol_refs and __stop__objc_protocol_refs sections |
| /// exist. |
| bool EmittedProtocolRef = false; |
| /// A flag indicating if we've emitted at least one class. |
| /// If we haven't, then we need to emit an empty protocol, to ensure that the |
| /// __start__objc_classes and __stop__objc_classes sections / exist. |
| bool EmittedClass = false; |
| /// Generate the name of a symbol for a reference to a class. Accesses to |
| /// classes should be indirected via this. |
| |
| typedef std::pair<std::string, std::pair<llvm::Constant*, int>> EarlyInitPair; |
| std::vector<EarlyInitPair> EarlyInitList; |
| |
| std::string SymbolForClassRef(StringRef Name, bool isWeak) { |
| if (isWeak) |
| return (ManglePublicSymbol("OBJC_WEAK_REF_CLASS_") + Name).str(); |
| else |
| return (ManglePublicSymbol("OBJC_REF_CLASS_") + Name).str(); |
| } |
| /// Generate the name of a class symbol. |
| std::string SymbolForClass(StringRef Name) { |
| return (ManglePublicSymbol("OBJC_CLASS_") + Name).str(); |
| } |
| void CallRuntimeFunction(CGBuilderTy &B, StringRef FunctionName, |
| ArrayRef<llvm::Value*> Args) { |
| SmallVector<llvm::Type *,8> Types; |
| for (auto *Arg : Args) |
| Types.push_back(Arg->getType()); |
| llvm::FunctionType *FT = llvm::FunctionType::get(B.getVoidTy(), Types, |
| false); |
| llvm::FunctionCallee Fn = CGM.CreateRuntimeFunction(FT, FunctionName); |
| B.CreateCall(Fn, Args); |
| } |
| |
| ConstantAddress GenerateConstantString(const StringLiteral *SL) override { |
| |
| auto Str = SL->getString(); |
| CharUnits Align = CGM.getPointerAlign(); |
| |
| // Look for an existing one |
| llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str); |
| if (old != ObjCStrings.end()) |
| return ConstantAddress(old->getValue(), Align); |
| |
| bool isNonASCII = SL->containsNonAscii(); |
| |
| auto LiteralLength = SL->getLength(); |
| |
| if ((CGM.getTarget().getPointerWidth(0) == 64) && |
| (LiteralLength < 9) && !isNonASCII) { |
| // Tiny strings are only used on 64-bit platforms. They store 8 7-bit |
| // ASCII characters in the high 56 bits, followed by a 4-bit length and a |
| // 3-bit tag (which is always 4). |
| uint64_t str = 0; |
| // Fill in the characters |
| for (unsigned i=0 ; i<LiteralLength ; i++) |
| str |= ((uint64_t)SL->getCodeUnit(i)) << ((64 - 4 - 3) - (i*7)); |
| // Fill in the length |
| str |= LiteralLength << 3; |
| // Set the tag |
| str |= 4; |
| auto *ObjCStr = llvm::ConstantExpr::getIntToPtr( |
| llvm::ConstantInt::get(Int64Ty, str), IdTy); |
| ObjCStrings[Str] = ObjCStr; |
| return ConstantAddress(ObjCStr, Align); |
| } |
| |
| StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass; |
| |
| if (StringClass.empty()) StringClass = "NSConstantString"; |
| |
| std::string Sym = SymbolForClass(StringClass); |
| |
| llvm::Constant *isa = TheModule.getNamedGlobal(Sym); |
| |
| if (!isa) { |
| isa = new llvm::GlobalVariable(TheModule, IdTy, /* isConstant */false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, Sym); |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| cast<llvm::GlobalValue>(isa)->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); |
| } |
| } else if (isa->getType() != PtrToIdTy) |
| isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy); |
| |
| // struct |
| // { |
| // Class isa; |
| // uint32_t flags; |
| // uint32_t length; // Number of codepoints |
| // uint32_t size; // Number of bytes |
| // uint32_t hash; |
| // const char *data; |
| // }; |
| |
| ConstantInitBuilder Builder(CGM); |
| auto Fields = Builder.beginStruct(); |
| if (!CGM.getTriple().isOSBinFormatCOFF()) { |
| Fields.add(isa); |
| } else { |
| Fields.addNullPointer(PtrTy); |
| } |
| // For now, all non-ASCII strings are represented as UTF-16. As such, the |
| // number of bytes is simply double the number of UTF-16 codepoints. In |
| // ASCII strings, the number of bytes is equal to the number of non-ASCII |
| // codepoints. |
| if (isNonASCII) { |
| unsigned NumU8CodeUnits = Str.size(); |
| // A UTF-16 representation of a unicode string contains at most the same |
| // number of code units as a UTF-8 representation. Allocate that much |
| // space, plus one for the final null character. |
| SmallVector<llvm::UTF16, 128> ToBuf(NumU8CodeUnits + 1); |
| const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)Str.data(); |
| llvm::UTF16 *ToPtr = &ToBuf[0]; |
| (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumU8CodeUnits, |
| &ToPtr, ToPtr + NumU8CodeUnits, llvm::strictConversion); |
| uint32_t StringLength = ToPtr - &ToBuf[0]; |
| // Add null terminator |
| *ToPtr = 0; |
| // Flags: 2 indicates UTF-16 encoding |
| Fields.addInt(Int32Ty, 2); |
| // Number of UTF-16 codepoints |
| Fields.addInt(Int32Ty, StringLength); |
| // Number of bytes |
| Fields.addInt(Int32Ty, StringLength * 2); |
| // Hash. Not currently initialised by the compiler. |
| Fields.addInt(Int32Ty, 0); |
| // pointer to the data string. |
| auto Arr = llvm::makeArrayRef(&ToBuf[0], ToPtr+1); |
| auto *C = llvm::ConstantDataArray::get(VMContext, Arr); |
| auto *Buffer = new llvm::GlobalVariable(TheModule, C->getType(), |
| /*isConstant=*/true, llvm::GlobalValue::PrivateLinkage, C, ".str"); |
| Buffer->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); |
| Fields.add(Buffer); |
| } else { |
| // Flags: 0 indicates ASCII encoding |
| Fields.addInt(Int32Ty, 0); |
| // Number of UTF-16 codepoints, each ASCII byte is a UTF-16 codepoint |
| Fields.addInt(Int32Ty, Str.size()); |
| // Number of bytes |
| Fields.addInt(Int32Ty, Str.size()); |
| // Hash. Not currently initialised by the compiler. |
| Fields.addInt(Int32Ty, 0); |
| // Data pointer |
| Fields.add(MakeConstantString(Str)); |
| } |
| std::string StringName; |
| bool isNamed = !isNonASCII; |
| if (isNamed) { |
| StringName = ".objc_str_"; |
| for (int i=0,e=Str.size() ; i<e ; ++i) { |
| unsigned char c = Str[i]; |
| if (isalnum(c)) |
| StringName += c; |
| else if (c == ' ') |
| StringName += '_'; |
| else { |
| isNamed = false; |
| break; |
| } |
| } |
| } |
| auto *ObjCStrGV = |
| Fields.finishAndCreateGlobal( |
| isNamed ? StringRef(StringName) : ".objc_string", |
| Align, false, isNamed ? llvm::GlobalValue::LinkOnceODRLinkage |
| : llvm::GlobalValue::PrivateLinkage); |
| ObjCStrGV->setSection(sectionName<ConstantStringSection>()); |
| if (isNamed) { |
| ObjCStrGV->setComdat(TheModule.getOrInsertComdat(StringName)); |
| ObjCStrGV->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| } |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| std::pair<llvm::Constant*, int> v{ObjCStrGV, 0}; |
| EarlyInitList.emplace_back(Sym, v); |
| } |
| llvm::Constant *ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStrGV, IdTy); |
| ObjCStrings[Str] = ObjCStr; |
| ConstantStrings.push_back(ObjCStr); |
| return ConstantAddress(ObjCStr, Align); |
| } |
| |
| void PushProperty(ConstantArrayBuilder &PropertiesArray, |
| const ObjCPropertyDecl *property, |
| const Decl *OCD, |
| bool isSynthesized=true, bool |
| isDynamic=true) override { |
| // struct objc_property |
| // { |
| // const char *name; |
| // const char *attributes; |
| // const char *type; |
| // SEL getter; |
| // SEL setter; |
| // }; |
| auto Fields = PropertiesArray.beginStruct(PropertyMetadataTy); |
| ASTContext &Context = CGM.getContext(); |
| Fields.add(MakeConstantString(property->getNameAsString())); |
| std::string TypeStr = |
| CGM.getContext().getObjCEncodingForPropertyDecl(property, OCD); |
| Fields.add(MakeConstantString(TypeStr)); |
| std::string typeStr; |
| Context.getObjCEncodingForType(property->getType(), typeStr); |
| Fields.add(MakeConstantString(typeStr)); |
| auto addPropertyMethod = [&](const ObjCMethodDecl *accessor) { |
| if (accessor) { |
| std::string TypeStr = Context.getObjCEncodingForMethodDecl(accessor); |
| Fields.add(GetConstantSelector(accessor->getSelector(), TypeStr)); |
| } else { |
| Fields.add(NULLPtr); |
| } |
| }; |
| addPropertyMethod(property->getGetterMethodDecl()); |
| addPropertyMethod(property->getSetterMethodDecl()); |
| Fields.finishAndAddTo(PropertiesArray); |
| } |
| |
| llvm::Constant * |
| GenerateProtocolMethodList(ArrayRef<const ObjCMethodDecl*> Methods) override { |
| // struct objc_protocol_method_description |
| // { |
| // SEL selector; |
| // const char *types; |
| // }; |
| llvm::StructType *ObjCMethodDescTy = |
| llvm::StructType::get(CGM.getLLVMContext(), |
| { PtrToInt8Ty, PtrToInt8Ty }); |
| ASTContext &Context = CGM.getContext(); |
| ConstantInitBuilder Builder(CGM); |
| // struct objc_protocol_method_description_list |
| // { |
| // int count; |
| // int size; |
| // struct objc_protocol_method_description methods[]; |
| // }; |
| auto MethodList = Builder.beginStruct(); |
| // int count; |
| MethodList.addInt(IntTy, Methods.size()); |
| // int size; // sizeof(struct objc_method_description) |
| llvm::DataLayout td(&TheModule); |
| MethodList.addInt(IntTy, td.getTypeSizeInBits(ObjCMethodDescTy) / |
| CGM.getContext().getCharWidth()); |
| // struct objc_method_description[] |
| auto MethodArray = MethodList.beginArray(ObjCMethodDescTy); |
| for (auto *M : Methods) { |
| auto Method = MethodArray.beginStruct(ObjCMethodDescTy); |
| Method.add(CGObjCGNU::GetConstantSelector(M)); |
| Method.add(GetTypeString(Context.getObjCEncodingForMethodDecl(M, true))); |
| Method.finishAndAddTo(MethodArray); |
| } |
| MethodArray.finishAndAddTo(MethodList); |
| return MethodList.finishAndCreateGlobal(".objc_protocol_method_list", |
| CGM.getPointerAlign()); |
| } |
| llvm::Constant *GenerateCategoryProtocolList(const ObjCCategoryDecl *OCD) |
| override { |
| SmallVector<llvm::Constant*, 16> Protocols; |
| for (const auto *PI : OCD->getReferencedProtocols()) |
| Protocols.push_back( |
| llvm::ConstantExpr::getBitCast(GenerateProtocolRef(PI), |
| ProtocolPtrTy)); |
| return GenerateProtocolList(Protocols); |
| } |
| |
| llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper, |
| llvm::Value *cmd, MessageSendInfo &MSI) override { |
| // Don't access the slot unless we're trying to cache the result. |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *lookupArgs[] = {CGObjCGNU::EnforceType(Builder, ObjCSuper, |
| PtrToObjCSuperTy).getPointer(), cmd}; |
| return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs); |
| } |
| |
| llvm::GlobalVariable *GetClassVar(StringRef Name, bool isWeak=false) { |
| std::string SymbolName = SymbolForClassRef(Name, isWeak); |
| auto *ClassSymbol = TheModule.getNamedGlobal(SymbolName); |
| if (ClassSymbol) |
| return ClassSymbol; |
| ClassSymbol = new llvm::GlobalVariable(TheModule, |
| IdTy, false, llvm::GlobalValue::ExternalLinkage, |
| nullptr, SymbolName); |
| // If this is a weak symbol, then we are creating a valid definition for |
| // the symbol, pointing to a weak definition of the real class pointer. If |
| // this is not a weak reference, then we are expecting another compilation |
| // unit to provide the real indirection symbol. |
| if (isWeak) |
| ClassSymbol->setInitializer(new llvm::GlobalVariable(TheModule, |
| Int8Ty, false, llvm::GlobalValue::ExternalWeakLinkage, |
| nullptr, SymbolForClass(Name))); |
| else { |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| IdentifierInfo &II = CGM.getContext().Idents.get(Name); |
| TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl(); |
| DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); |
| |
| const ObjCInterfaceDecl *OID = nullptr; |
| for (const auto &Result : DC->lookup(&II)) |
| if ((OID = dyn_cast<ObjCInterfaceDecl>(Result))) |
| break; |
| |
| // The first Interface we find may be a @class, |
| // which should only be treated as the source of |
| // truth in the absence of a true declaration. |
| assert(OID && "Failed to find ObjCInterfaceDecl"); |
| const ObjCInterfaceDecl *OIDDef = OID->getDefinition(); |
| if (OIDDef != nullptr) |
| OID = OIDDef; |
| |
| auto Storage = llvm::GlobalValue::DefaultStorageClass; |
| if (OID->hasAttr<DLLImportAttr>()) |
| Storage = llvm::GlobalValue::DLLImportStorageClass; |
| else if (OID->hasAttr<DLLExportAttr>()) |
| Storage = llvm::GlobalValue::DLLExportStorageClass; |
| |
| cast<llvm::GlobalValue>(ClassSymbol)->setDLLStorageClass(Storage); |
| } |
| } |
| assert(ClassSymbol->getName() == SymbolName); |
| return ClassSymbol; |
| } |
| llvm::Value *GetClassNamed(CodeGenFunction &CGF, |
| const std::string &Name, |
| bool isWeak) override { |
| return CGF.Builder.CreateLoad(Address(GetClassVar(Name, isWeak), |
| CGM.getPointerAlign())); |
| } |
| int32_t FlagsForOwnership(Qualifiers::ObjCLifetime Ownership) { |
| // typedef enum { |
| // ownership_invalid = 0, |
| // ownership_strong = 1, |
| // ownership_weak = 2, |
| // ownership_unsafe = 3 |
| // } ivar_ownership; |
| int Flag; |
| switch (Ownership) { |
| case Qualifiers::OCL_Strong: |
| Flag = 1; |
| break; |
| case Qualifiers::OCL_Weak: |
| Flag = 2; |
| break; |
| case Qualifiers::OCL_ExplicitNone: |
| Flag = 3; |
| break; |
| case Qualifiers::OCL_None: |
| case Qualifiers::OCL_Autoreleasing: |
| assert(Ownership != Qualifiers::OCL_Autoreleasing); |
| Flag = 0; |
| } |
| return Flag; |
| } |
| llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames, |
| ArrayRef<llvm::Constant *> IvarTypes, |
| ArrayRef<llvm::Constant *> IvarOffsets, |
| ArrayRef<llvm::Constant *> IvarAlign, |
| ArrayRef<Qualifiers::ObjCLifetime> IvarOwnership) override { |
| llvm_unreachable("Method should not be called!"); |
| } |
| |
| llvm::Constant *GenerateEmptyProtocol(StringRef ProtocolName) override { |
| std::string Name = SymbolForProtocol(ProtocolName); |
| auto *GV = TheModule.getGlobalVariable(Name); |
| if (!GV) { |
| // Emit a placeholder symbol. |
| GV = new llvm::GlobalVariable(TheModule, ProtocolTy, false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, Name); |
| GV->setAlignment(CGM.getPointerAlign().getAsAlign()); |
| } |
| return llvm::ConstantExpr::getBitCast(GV, ProtocolPtrTy); |
| } |
| |
| /// Existing protocol references. |
| llvm::StringMap<llvm::Constant*> ExistingProtocolRefs; |
| |
| llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF, |
| const ObjCProtocolDecl *PD) override { |
| auto Name = PD->getNameAsString(); |
| auto *&Ref = ExistingProtocolRefs[Name]; |
| if (!Ref) { |
| auto *&Protocol = ExistingProtocols[Name]; |
| if (!Protocol) |
| Protocol = GenerateProtocolRef(PD); |
| std::string RefName = SymbolForProtocolRef(Name); |
| assert(!TheModule.getGlobalVariable(RefName)); |
| // Emit a reference symbol. |
| auto GV = new llvm::GlobalVariable(TheModule, ProtocolPtrTy, |
| false, llvm::GlobalValue::LinkOnceODRLinkage, |
| llvm::ConstantExpr::getBitCast(Protocol, ProtocolPtrTy), RefName); |
| GV->setComdat(TheModule.getOrInsertComdat(RefName)); |
| GV->setSection(sectionName<ProtocolReferenceSection>()); |
| GV->setAlignment(CGM.getPointerAlign().getAsAlign()); |
| Ref = GV; |
| } |
| EmittedProtocolRef = true; |
| return CGF.Builder.CreateAlignedLoad(Ref, CGM.getPointerAlign()); |
| } |
| |
| llvm::Constant *GenerateProtocolList(ArrayRef<llvm::Constant*> Protocols) { |
| llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(ProtocolPtrTy, |
| Protocols.size()); |
| llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy, |
| Protocols); |
| ConstantInitBuilder builder(CGM); |
| auto ProtocolBuilder = builder.beginStruct(); |
| ProtocolBuilder.addNullPointer(PtrTy); |
| ProtocolBuilder.addInt(SizeTy, Protocols.size()); |
| ProtocolBuilder.add(ProtocolArray); |
| return ProtocolBuilder.finishAndCreateGlobal(".objc_protocol_list", |
| CGM.getPointerAlign(), false, llvm::GlobalValue::InternalLinkage); |
| } |
| |
| void GenerateProtocol(const ObjCProtocolDecl *PD) override { |
| // Do nothing - we only emit referenced protocols. |
| } |
| llvm::Constant *GenerateProtocolRef(const ObjCProtocolDecl *PD) override { |
| std::string ProtocolName = PD->getNameAsString(); |
| auto *&Protocol = ExistingProtocols[ProtocolName]; |
| if (Protocol) |
| return Protocol; |
| |
| EmittedProtocol = true; |
| |
| auto SymName = SymbolForProtocol(ProtocolName); |
| auto *OldGV = TheModule.getGlobalVariable(SymName); |
| |
| // Use the protocol definition, if there is one. |
| if (const ObjCProtocolDecl *Def = PD->getDefinition()) |
| PD = Def; |
| else { |
| // If there is no definition, then create an external linkage symbol and |
| // hope that someone else fills it in for us (and fail to link if they |
| // don't). |
| assert(!OldGV); |
| Protocol = new llvm::GlobalVariable(TheModule, ProtocolTy, |
| /*isConstant*/false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, SymName); |
| return Protocol; |
| } |
| |
| SmallVector<llvm::Constant*, 16> Protocols; |
| for (const auto *PI : PD->protocols()) |
| Protocols.push_back( |
| llvm::ConstantExpr::getBitCast(GenerateProtocolRef(PI), |
| ProtocolPtrTy)); |
| llvm::Constant *ProtocolList = GenerateProtocolList(Protocols); |
| |
| // Collect information about methods |
| llvm::Constant *InstanceMethodList, *OptionalInstanceMethodList; |
| llvm::Constant *ClassMethodList, *OptionalClassMethodList; |
| EmitProtocolMethodList(PD->instance_methods(), InstanceMethodList, |
| OptionalInstanceMethodList); |
| EmitProtocolMethodList(PD->class_methods(), ClassMethodList, |
| OptionalClassMethodList); |
| |
| // The isa pointer must be set to a magic number so the runtime knows it's |
| // the correct layout. |
| ConstantInitBuilder builder(CGM); |
| auto ProtocolBuilder = builder.beginStruct(); |
| ProtocolBuilder.add(llvm::ConstantExpr::getIntToPtr( |
| llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy)); |
| ProtocolBuilder.add(MakeConstantString(ProtocolName)); |
| ProtocolBuilder.add(ProtocolList); |
| ProtocolBuilder.add(InstanceMethodList); |
| ProtocolBuilder.add(ClassMethodList); |
| ProtocolBuilder.add(OptionalInstanceMethodList); |
| ProtocolBuilder.add(OptionalClassMethodList); |
| // Required instance properties |
| ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, false, false)); |
| // Optional instance properties |
| ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, false, true)); |
| // Required class properties |
| ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, true, false)); |
| // Optional class properties |
| ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, true, true)); |
| |
| auto *GV = ProtocolBuilder.finishAndCreateGlobal(SymName, |
| CGM.getPointerAlign(), false, llvm::GlobalValue::ExternalLinkage); |
| GV->setSection(sectionName<ProtocolSection>()); |
| GV->setComdat(TheModule.getOrInsertComdat(SymName)); |
| if (OldGV) { |
| OldGV->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GV, |
| OldGV->getType())); |
| OldGV->removeFromParent(); |
| GV->setName(SymName); |
| } |
| Protocol = GV; |
| return GV; |
| } |
| llvm::Constant *EnforceType(llvm::Constant *Val, llvm::Type *Ty) { |
| if (Val->getType() == Ty) |
| return Val; |
| return llvm::ConstantExpr::getBitCast(Val, Ty); |
| } |
| llvm::Value *GetTypedSelector(CodeGenFunction &CGF, Selector Sel, |
| const std::string &TypeEncoding) override { |
| return GetConstantSelector(Sel, TypeEncoding); |
| } |
| llvm::Constant *GetTypeString(llvm::StringRef TypeEncoding) { |
| if (TypeEncoding.empty()) |
| return NULLPtr; |
| std::string MangledTypes = std::string(TypeEncoding); |
| std::replace(MangledTypes.begin(), MangledTypes.end(), |
| '@', '\1'); |
| std::string TypesVarName = ".objc_sel_types_" + MangledTypes; |
| auto *TypesGlobal = TheModule.getGlobalVariable(TypesVarName); |
| if (!TypesGlobal) { |
| llvm::Constant *Init = llvm::ConstantDataArray::getString(VMContext, |
| TypeEncoding); |
| auto *GV = new llvm::GlobalVariable(TheModule, Init->getType(), |
| true, llvm::GlobalValue::LinkOnceODRLinkage, Init, TypesVarName); |
| GV->setComdat(TheModule.getOrInsertComdat(TypesVarName)); |
| GV->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| TypesGlobal = GV; |
| } |
| return llvm::ConstantExpr::getGetElementPtr(TypesGlobal->getValueType(), |
| TypesGlobal, Zeros); |
| } |
| llvm::Constant *GetConstantSelector(Selector Sel, |
| const std::string &TypeEncoding) override { |
| // @ is used as a special character in symbol names (used for symbol |
| // versioning), so mangle the name to not include it. Replace it with a |
| // character that is not a valid type encoding character (and, being |
| // non-printable, never will be!) |
| std::string MangledTypes = TypeEncoding; |
| std::replace(MangledTypes.begin(), MangledTypes.end(), |
| '@', '\1'); |
| auto SelVarName = (StringRef(".objc_selector_") + Sel.getAsString() + "_" + |
| MangledTypes).str(); |
| if (auto *GV = TheModule.getNamedGlobal(SelVarName)) |
| return EnforceType(GV, SelectorTy); |
| ConstantInitBuilder builder(CGM); |
| auto SelBuilder = builder.beginStruct(); |
| SelBuilder.add(ExportUniqueString(Sel.getAsString(), ".objc_sel_name_", |
| true)); |
| SelBuilder.add(GetTypeString(TypeEncoding)); |
| auto *GV = SelBuilder.finishAndCreateGlobal(SelVarName, |
| CGM.getPointerAlign(), false, llvm::GlobalValue::LinkOnceODRLinkage); |
| GV->setComdat(TheModule.getOrInsertComdat(SelVarName)); |
| GV->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| GV->setSection(sectionName<SelectorSection>()); |
| auto *SelVal = EnforceType(GV, SelectorTy); |
| return SelVal; |
| } |
| llvm::StructType *emptyStruct = nullptr; |
| |
| /// Return pointers to the start and end of a section. On ELF platforms, we |
| /// use the __start_ and __stop_ symbols that GNU-compatible linkers will set |
| /// to the start and end of section names, as long as those section names are |
| /// valid identifiers and the symbols are referenced but not defined. On |
| /// Windows, we use the fact that MSVC-compatible linkers will lexically sort |
| /// by subsections and place everything that we want to reference in a middle |
| /// subsection and then insert zero-sized symbols in subsections a and z. |
| std::pair<llvm::Constant*,llvm::Constant*> |
| GetSectionBounds(StringRef Section) { |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| if (emptyStruct == nullptr) { |
| emptyStruct = llvm::StructType::create(VMContext, ".objc_section_sentinel"); |
| emptyStruct->setBody({}, /*isPacked*/true); |
| } |
| auto ZeroInit = llvm::Constant::getNullValue(emptyStruct); |
| auto Sym = [&](StringRef Prefix, StringRef SecSuffix) { |
| auto *Sym = new llvm::GlobalVariable(TheModule, emptyStruct, |
| /*isConstant*/false, |
| llvm::GlobalValue::LinkOnceODRLinkage, ZeroInit, Prefix + |
| Section); |
| Sym->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| Sym->setSection((Section + SecSuffix).str()); |
| Sym->setComdat(TheModule.getOrInsertComdat((Prefix + |
| Section).str())); |
| Sym->setAlignment(CGM.getPointerAlign().getAsAlign()); |
| return Sym; |
| }; |
| return { Sym("__start_", "$a"), Sym("__stop", "$z") }; |
| } |
| auto *Start = new llvm::GlobalVariable(TheModule, PtrTy, |
| /*isConstant*/false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, StringRef("__start_") + |
| Section); |
| Start->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| auto *Stop = new llvm::GlobalVariable(TheModule, PtrTy, |
| /*isConstant*/false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, StringRef("__stop_") + |
| Section); |
| Stop->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| return { Start, Stop }; |
| } |
| CatchTypeInfo getCatchAllTypeInfo() override { |
| return CGM.getCXXABI().getCatchAllTypeInfo(); |
| } |
| llvm::Function *ModuleInitFunction() override { |
| llvm::Function *LoadFunction = llvm::Function::Create( |
| llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false), |
| llvm::GlobalValue::LinkOnceODRLinkage, ".objcv2_load_function", |
| &TheModule); |
| LoadFunction->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| LoadFunction->setComdat(TheModule.getOrInsertComdat(".objcv2_load_function")); |
| |
| llvm::BasicBlock *EntryBB = |
| llvm::BasicBlock::Create(VMContext, "entry", LoadFunction); |
| CGBuilderTy B(CGM, VMContext); |
| B.SetInsertPoint(EntryBB); |
| ConstantInitBuilder builder(CGM); |
| auto InitStructBuilder = builder.beginStruct(); |
| InitStructBuilder.addInt(Int64Ty, 0); |
| auto §ionVec = CGM.getTriple().isOSBinFormatCOFF() ? PECOFFSectionsBaseNames : SectionsBaseNames; |
| for (auto *s : sectionVec) { |
| auto bounds = GetSectionBounds(s); |
| InitStructBuilder.add(bounds.first); |
| InitStructBuilder.add(bounds.second); |
| } |
| auto *InitStruct = InitStructBuilder.finishAndCreateGlobal(".objc_init", |
| CGM.getPointerAlign(), false, llvm::GlobalValue::LinkOnceODRLinkage); |
| InitStruct->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| InitStruct->setComdat(TheModule.getOrInsertComdat(".objc_init")); |
| |
| CallRuntimeFunction(B, "__objc_load", {InitStruct});; |
| B.CreateRetVoid(); |
| // Make sure that the optimisers don't delete this function. |
| CGM.addCompilerUsedGlobal(LoadFunction); |
| // FIXME: Currently ELF only! |
| // We have to do this by hand, rather than with @llvm.ctors, so that the |
| // linker can remove the duplicate invocations. |
| auto *InitVar = new llvm::GlobalVariable(TheModule, LoadFunction->getType(), |
| /*isConstant*/false, llvm::GlobalValue::LinkOnceAnyLinkage, |
| LoadFunction, ".objc_ctor"); |
| // Check that this hasn't been renamed. This shouldn't happen, because |
| // this function should be called precisely once. |
| assert(InitVar->getName() == ".objc_ctor"); |
| // In Windows, initialisers are sorted by the suffix. XCL is for library |
| // initialisers, which run before user initialisers. We are running |
| // Objective-C loads at the end of library load. This means +load methods |
| // will run before any other static constructors, but that static |
| // constructors can see a fully initialised Objective-C state. |
| if (CGM.getTriple().isOSBinFormatCOFF()) |
| InitVar->setSection(".CRT$XCLz"); |
| else |
| { |
| if (CGM.getCodeGenOpts().UseInitArray) |
| InitVar->setSection(".init_array"); |
| else |
| InitVar->setSection(".ctors"); |
| } |
| InitVar->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| InitVar->setComdat(TheModule.getOrInsertComdat(".objc_ctor")); |
| CGM.addUsedGlobal(InitVar); |
| for (auto *C : Categories) { |
| auto *Cat = cast<llvm::GlobalVariable>(C->stripPointerCasts()); |
| Cat->setSection(sectionName<CategorySection>()); |
| CGM.addUsedGlobal(Cat); |
| } |
| auto createNullGlobal = [&](StringRef Name, ArrayRef<llvm::Constant*> Init, |
| StringRef Section) { |
| auto nullBuilder = builder.beginStruct(); |
| for (auto *F : Init) |
| nullBuilder.add(F); |
| auto GV = nullBuilder.finishAndCreateGlobal(Name, CGM.getPointerAlign(), |
| false, llvm::GlobalValue::LinkOnceODRLinkage); |
| GV->setSection(Section); |
| GV->setComdat(TheModule.getOrInsertComdat(Name)); |
| GV->setVisibility(llvm::GlobalValue::HiddenVisibility); |
| CGM.addUsedGlobal(GV); |
| return GV; |
| }; |
| for (auto clsAlias : ClassAliases) |
| createNullGlobal(std::string(".objc_class_alias") + |
| clsAlias.second, { MakeConstantString(clsAlias.second), |
| GetClassVar(clsAlias.first) }, sectionName<ClassAliasSection>()); |
| // On ELF platforms, add a null value for each special section so that we |
| // can always guarantee that the _start and _stop symbols will exist and be |
| // meaningful. This is not required on COFF platforms, where our start and |
| // stop symbols will create the section. |
| if (!CGM.getTriple().isOSBinFormatCOFF()) { |
| createNullGlobal(".objc_null_selector", {NULLPtr, NULLPtr}, |
| sectionName<SelectorSection>()); |
| if (Categories.empty()) |
| createNullGlobal(".objc_null_category", {NULLPtr, NULLPtr, |
| NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr}, |
| sectionName<CategorySection>()); |
| if (!EmittedClass) { |
| createNullGlobal(".objc_null_cls_init_ref", NULLPtr, |
| sectionName<ClassSection>()); |
| createNullGlobal(".objc_null_class_ref", { NULLPtr, NULLPtr }, |
| sectionName<ClassReferenceSection>()); |
| } |
| if (!EmittedProtocol) |
| createNullGlobal(".objc_null_protocol", {NULLPtr, NULLPtr, NULLPtr, |
| NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr, |
| NULLPtr}, sectionName<ProtocolSection>()); |
| if (!EmittedProtocolRef) |
| createNullGlobal(".objc_null_protocol_ref", {NULLPtr}, |
| sectionName<ProtocolReferenceSection>()); |
| if (ClassAliases.empty()) |
| createNullGlobal(".objc_null_class_alias", { NULLPtr, NULLPtr }, |
| sectionName<ClassAliasSection>()); |
| if (ConstantStrings.empty()) { |
| auto i32Zero = llvm::ConstantInt::get(Int32Ty, 0); |
| createNullGlobal(".objc_null_constant_string", { NULLPtr, i32Zero, |
| i32Zero, i32Zero, i32Zero, NULLPtr }, |
| sectionName<ConstantStringSection>()); |
| } |
| } |
| ConstantStrings.clear(); |
| Categories.clear(); |
| Classes.clear(); |
| |
| if (EarlyInitList.size() > 0) { |
| auto *Init = llvm::Function::Create(llvm::FunctionType::get(CGM.VoidTy, |
| {}), llvm::GlobalValue::InternalLinkage, ".objc_early_init", |
| &CGM.getModule()); |
| llvm::IRBuilder<> b(llvm::BasicBlock::Create(CGM.getLLVMContext(), "entry", |
| Init)); |
| for (const auto &lateInit : EarlyInitList) { |
| auto *global = TheModule.getGlobalVariable(lateInit.first); |
| if (global) { |
| b.CreateAlignedStore( |
| global, |
| b.CreateStructGEP(lateInit.second.first, lateInit.second.second), |
| CGM.getPointerAlign().getAsAlign()); |
| } |
| } |
| b.CreateRetVoid(); |
| // We can't use the normal LLVM global initialisation array, because we |
| // need to specify that this runs early in library initialisation. |
| auto *InitVar = new llvm::GlobalVariable(CGM.getModule(), Init->getType(), |
| /*isConstant*/true, llvm::GlobalValue::InternalLinkage, |
| Init, ".objc_early_init_ptr"); |
| InitVar->setSection(".CRT$XCLb"); |
| CGM.addUsedGlobal(InitVar); |
| } |
| return nullptr; |
| } |
| /// In the v2 ABI, ivar offset variables use the type encoding in their name |
| /// to trigger linker failures if the types don't match. |
| std::string GetIVarOffsetVariableName(const ObjCInterfaceDecl *ID, |
| const ObjCIvarDecl *Ivar) override { |
| std::string TypeEncoding; |
| CGM.getContext().getObjCEncodingForType(Ivar->getType(), TypeEncoding); |
| // Prevent the @ from being interpreted as a symbol version. |
| std::replace(TypeEncoding.begin(), TypeEncoding.end(), |
| '@', '\1'); |
| const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString() |
| + '.' + Ivar->getNameAsString() + '.' + TypeEncoding; |
| return Name; |
| } |
| llvm::Value *EmitIvarOffset(CodeGenFunction &CGF, |
| const ObjCInterfaceDecl *Interface, |
| const ObjCIvarDecl *Ivar) override { |
| const std::string Name = GetIVarOffsetVariableName(Ivar->getContainingInterface(), Ivar); |
| llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name); |
| if (!IvarOffsetPointer) |
| IvarOffsetPointer = new llvm::GlobalVariable(TheModule, IntTy, false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, Name); |
| CharUnits Align = CGM.getIntAlign(); |
| llvm::Value *Offset = CGF.Builder.CreateAlignedLoad(IvarOffsetPointer, Align); |
| if (Offset->getType() != PtrDiffTy) |
| Offset = CGF.Builder.CreateZExtOrBitCast(Offset, PtrDiffTy); |
| return Offset; |
| } |
| void GenerateClass(const ObjCImplementationDecl *OID) override { |
| ASTContext &Context = CGM.getContext(); |
| bool IsCOFF = CGM.getTriple().isOSBinFormatCOFF(); |
| |
| // Get the class name |
| ObjCInterfaceDecl *classDecl = |
| const_cast<ObjCInterfaceDecl *>(OID->getClassInterface()); |
| std::string className = classDecl->getNameAsString(); |
| auto *classNameConstant = MakeConstantString(className); |
| |
| ConstantInitBuilder builder(CGM); |
| auto metaclassFields = builder.beginStruct(); |
| // struct objc_class *isa; |
| metaclassFields.addNullPointer(PtrTy); |
| // struct objc_class *super_class; |
| metaclassFields.addNullPointer(PtrTy); |
| // const char *name; |
| metaclassFields.add(classNameConstant); |
| // long version; |
| metaclassFields.addInt(LongTy, 0); |
| // unsigned long info; |
| // objc_class_flag_meta |
| metaclassFields.addInt(LongTy, 1); |
| // long instance_size; |
| // Setting this to zero is consistent with the older ABI, but it might be |
| // more sensible to set this to sizeof(struct objc_class) |
| metaclassFields.addInt(LongTy, 0); |
| // struct objc_ivar_list *ivars; |
| metaclassFields.addNullPointer(PtrTy); |
| // struct objc_method_list *methods |
| // FIXME: Almost identical code is copied and pasted below for the |
| // class, but refactoring it cleanly requires C++14 generic lambdas. |
| if (OID->classmeth_begin() == OID->classmeth_end()) |
| metaclassFields.addNullPointer(PtrTy); |
| else { |
| SmallVector<ObjCMethodDecl*, 16> ClassMethods; |
| ClassMethods.insert(ClassMethods.begin(), OID->classmeth_begin(), |
| OID->classmeth_end()); |
| metaclassFields.addBitCast( |
| GenerateMethodList(className, "", ClassMethods, true), |
| PtrTy); |
| } |
| // void *dtable; |
| metaclassFields.addNullPointer(PtrTy); |
| // IMP cxx_construct; |
| metaclassFields.addNullPointer(PtrTy); |
| // IMP cxx_destruct; |
| metaclassFields.addNullPointer(PtrTy); |
| // struct objc_class *subclass_list |
| metaclassFields.addNullPointer(PtrTy); |
| // struct objc_class *sibling_class |
| metaclassFields.addNullPointer(PtrTy); |
| // struct objc_protocol_list *protocols; |
| metaclassFields.addNullPointer(PtrTy); |
| // struct reference_list *extra_data; |
| metaclassFields.addNullPointer(PtrTy); |
| // long abi_version; |
| metaclassFields.addInt(LongTy, 0); |
| // struct objc_property_list *properties |
| metaclassFields.add(GeneratePropertyList(OID, classDecl, /*isClassProperty*/true)); |
| |
| auto *metaclass = metaclassFields.finishAndCreateGlobal( |
| ManglePublicSymbol("OBJC_METACLASS_") + className, |
| CGM.getPointerAlign()); |
| |
| auto classFields = builder.beginStruct(); |
| // struct objc_class *isa; |
| classFields.add(metaclass); |
| // struct objc_class *super_class; |
| // Get the superclass name. |
| const ObjCInterfaceDecl * SuperClassDecl = |
| OID->getClassInterface()->getSuperClass(); |
| llvm::Constant *SuperClass = nullptr; |
| if (SuperClassDecl) { |
| auto SuperClassName = SymbolForClass(SuperClassDecl->getNameAsString()); |
| SuperClass = TheModule.getNamedGlobal(SuperClassName); |
| if (!SuperClass) |
| { |
| SuperClass = new llvm::GlobalVariable(TheModule, PtrTy, false, |
| llvm::GlobalValue::ExternalLinkage, nullptr, SuperClassName); |
| if (IsCOFF) { |
| auto Storage = llvm::GlobalValue::DefaultStorageClass; |
| if (SuperClassDecl->hasAttr<DLLImportAttr>()) |
| Storage = llvm::GlobalValue::DLLImportStorageClass; |
| else if (SuperClassDecl->hasAttr<DLLExportAttr>()) |
| Storage = llvm::GlobalValue::DLLExportStorageClass; |
| |
| cast<llvm::GlobalValue>(SuperClass)->setDLLStorageClass(Storage); |
| } |
| } |
| if (!IsCOFF) |
| classFields.add(llvm::ConstantExpr::getBitCast(SuperClass, PtrTy)); |
| else |
| classFields.addNullPointer(PtrTy); |
| } else |
| classFields.addNullPointer(PtrTy); |
| // const char *name; |
| classFields.add(classNameConstant); |
| // long version; |
| classFields.addInt(LongTy, 0); |
| // unsigned long info; |
| // !objc_class_flag_meta |
| classFields.addInt(LongTy, 0); |
| // long instance_size; |
| int superInstanceSize = !SuperClassDecl ? 0 : |
| Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity(); |
| // Instance size is negative for classes that have not yet had their ivar |
| // layout calculated. |
| classFields.addInt(LongTy, |
| 0 - (Context.getASTObjCImplementationLayout(OID).getSize().getQuantity() - |
| superInstanceSize)); |
| |
| if (classDecl->all_declared_ivar_begin() == nullptr) |
| classFields.addNullPointer(PtrTy); |
| else { |
| int ivar_count = 0; |
| for (const ObjCIvarDecl *IVD = classDecl->all_declared_ivar_begin(); IVD; |
| IVD = IVD->getNextIvar()) ivar_count++; |
| llvm::DataLayout td(&TheModule); |
| // struct objc_ivar_list *ivars; |
| ConstantInitBuilder b(CGM); |
| auto ivarListBuilder = b.beginStruct(); |
| // int count; |
| ivarListBuilder.addInt(IntTy, ivar_count); |
| // size_t size; |
| llvm::StructType *ObjCIvarTy = llvm::StructType::get( |
| PtrToInt8Ty, |
| PtrToInt8Ty, |
| PtrToInt8Ty, |
| Int32Ty, |
| Int32Ty); |
| ivarListBuilder.addInt(SizeTy, td.getTypeSizeInBits(ObjCIvarTy) / |
| CGM.getContext().getCharWidth()); |
| // struct objc_ivar ivars[] |
| auto ivarArrayBuilder = ivarListBuilder.beginArray(); |
| for (const ObjCIvarDecl *IVD = classDecl->all_declared_ivar_begin(); IVD; |
| IVD = IVD->getNextIvar()) { |
| auto ivarTy = IVD->getType(); |
| auto ivarBuilder = ivarArrayBuilder.beginStruct(); |
| // const char *name; |
| ivarBuilder.add(MakeConstantString(IVD->getNameAsString())); |
| // const char *type; |
| std::string TypeStr; |
| //Context.getObjCEncodingForType(ivarTy, TypeStr, IVD, true); |
| Context.getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, ivarTy, TypeStr, true); |
| ivarBuilder.add(MakeConstantString(TypeStr)); |
| // int *offset; |
| uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD); |
| uint64_t Offset = BaseOffset - superInstanceSize; |
| llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset); |
| std::string OffsetName = GetIVarOffsetVariableName(classDecl, IVD); |
| llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName); |
| if (OffsetVar) |
| OffsetVar->setInitializer(OffsetValue); |
| else |
| OffsetVar = new llvm::GlobalVariable(TheModule, IntTy, |
| false, llvm::GlobalValue::ExternalLinkage, |
| OffsetValue, OffsetName); |
| auto ivarVisibility = |
| (IVD->getAccessControl() == ObjCIvarDecl::Private || |
| IVD->getAccessControl() == ObjCIvarDecl::Package || |
| classDecl->getVisibility() == HiddenVisibility) ? |
| llvm::GlobalValue::HiddenVisibility : |
| llvm::GlobalValue::DefaultVisibility; |
| OffsetVar->setVisibility(ivarVisibility); |
| ivarBuilder.add(OffsetVar); |
| // Ivar size |
| ivarBuilder.addInt(Int32Ty, |
| CGM.getContext().getTypeSizeInChars(ivarTy).getQuantity()); |
| // Alignment will be stored as a base-2 log of the alignment. |
| unsigned align = |
| llvm::Log2_32(Context.getTypeAlignInChars(ivarTy).getQuantity()); |
| // Objects that require more than 2^64-byte alignment should be impossible! |
| assert(align < 64); |
| // uint32_t flags; |
| // Bits 0-1 are ownership. |
| // Bit 2 indicates an extended type encoding |
| // Bits 3-8 contain log2(aligment) |
| ivarBuilder.addInt(Int32Ty, |
| (align << 3) | (1<<2) | |
| FlagsForOwnership(ivarTy.getQualifiers().getObjCLifetime())); |
| ivarBuilder.finishAndAddTo(ivarArrayBuilder); |
| } |
| ivarArrayBuilder.finishAndAddTo(ivarListBuilder); |
| auto ivarList = ivarListBuilder.finishAndCreateGlobal(".objc_ivar_list", |
| CGM.getPointerAlign(), /*constant*/ false, |
| llvm::GlobalValue::PrivateLinkage); |
| classFields.add(ivarList); |
| } |
| // struct objc_method_list *methods |
| SmallVector<const ObjCMethodDecl*, 16> InstanceMethods; |
| InstanceMethods.insert(InstanceMethods.begin(), OID->instmeth_begin(), |
| OID->instmeth_end()); |
| for (auto *propImpl : OID->property_impls()) |
| if (propImpl->getPropertyImplementation() == |
| ObjCPropertyImplDecl::Synthesize) { |
| auto addIfExists = [&](const ObjCMethodDecl *OMD) { |
| if (OMD && OMD->hasBody()) |
| InstanceMethods.push_back(OMD); |
| }; |
| addIfExists(propImpl->getGetterMethodDecl()); |
| addIfExists(propImpl->getSetterMethodDecl()); |
| } |
| |
| if (InstanceMethods.size() == 0) |
| classFields.addNullPointer(PtrTy); |
| else |
| classFields.addBitCast( |
| GenerateMethodList(className, "", InstanceMethods, false), |
| PtrTy); |
| // void *dtable; |
| classFields.addNullPointer(PtrTy); |
| // IMP cxx_construct; |
| classFields.addNullPointer(PtrTy); |
| // IMP cxx_destruct; |
| classFields.addNullPointer(PtrTy); |
| // struct objc_class *subclass_list |
| classFields.addNullPointer(PtrTy); |
| // struct objc_class *sibling_class |
| classFields.addNullPointer(PtrTy); |
| // struct objc_protocol_list *protocols; |
| SmallVector<llvm::Constant*, 16> Protocols; |
| for (const auto *I : classDecl->protocols()) |
| Protocols.push_back( |
| llvm::ConstantExpr::getBitCast(GenerateProtocolRef(I), |
| ProtocolPtrTy)); |
| if (Protocols.empty()) |
| classFields.addNullPointer(PtrTy); |
| else |
| classFields.add(GenerateProtocolList(Protocols)); |
| // struct reference_list *extra_data; |
| classFields.addNullPointer(PtrTy); |
| // long abi_version; |
| classFields.addInt(LongTy, 0); |
| // struct objc_property_list *properties |
| classFields.add(GeneratePropertyList(OID, classDecl)); |
| |
| auto *classStruct = |
| classFields.finishAndCreateGlobal(SymbolForClass(className), |
| CGM.getPointerAlign(), false, llvm::GlobalValue::ExternalLinkage); |
| |
| auto *classRefSymbol = GetClassVar(className); |
| classRefSymbol->setSection(sectionName<ClassReferenceSection>()); |
| classRefSymbol->setInitializer(llvm::ConstantExpr::getBitCast(classStruct, IdTy)); |
| |
| if (IsCOFF) { |
| // we can't import a class struct. |
| if (OID->getClassInterface()->hasAttr<DLLExportAttr>()) { |
| cast<llvm::GlobalValue>(classStruct)->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); |
| cast<llvm::GlobalValue>(classRefSymbol)->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); |
| } |
| |
| if (SuperClass) { |
| std::pair<llvm::Constant*, int> v{classStruct, 1}; |
| EarlyInitList.emplace_back(std::string(SuperClass->getName()), |
| std::move(v)); |
| } |
| |
| } |
| |
| |
| // Resolve the class aliases, if they exist. |
| // FIXME: Class pointer aliases shouldn't exist! |
| if (ClassPtrAlias) { |
| ClassPtrAlias->replaceAllUsesWith( |
| llvm::ConstantExpr::getBitCast(classStruct, IdTy)); |
| ClassPtrAlias->eraseFromParent(); |
| ClassPtrAlias = nullptr; |
| } |
| if (auto Placeholder = |
| TheModule.getNamedGlobal(SymbolForClass(className))) |
| if (Placeholder != classStruct) { |
| Placeholder->replaceAllUsesWith( |
| llvm::ConstantExpr::getBitCast(classStruct, Placeholder->getType())); |
| Placeholder->eraseFromParent(); |
| classStruct->setName(SymbolForClass(className)); |
| } |
| if (MetaClassPtrAlias) { |
| MetaClassPtrAlias->replaceAllUsesWith( |
| llvm::ConstantExpr::getBitCast(metaclass, IdTy)); |
| MetaClassPtrAlias->eraseFromParent(); |
| MetaClassPtrAlias = nullptr; |
| } |
| assert(classStruct->getName() == SymbolForClass(className)); |
| |
| auto classInitRef = new llvm::GlobalVariable(TheModule, |
| classStruct->getType(), false, llvm::GlobalValue::ExternalLinkage, |
| classStruct, ManglePublicSymbol("OBJC_INIT_CLASS_") + className); |
| classInitRef->setSection(sectionName<ClassSection>()); |
| CGM.addUsedGlobal(classInitRef); |
| |
| EmittedClass = true; |
| } |
| public: |
| CGObjCGNUstep2(CodeGenModule &Mod) : CGObjCGNUstep(Mod, 10, 4, 2) { |
| MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy, |
| PtrToObjCSuperTy, SelectorTy); |
| // struct objc_property |
| // { |
| // const char *name; |
| // const char *attributes; |
| // const char *type; |
| // SEL getter; |
| // SEL setter; |
| // } |
| PropertyMetadataTy = |
| llvm::StructType::get(CGM.getLLVMContext(), |
| { PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty }); |
| } |
| |
| }; |
| |
| const char *const CGObjCGNUstep2::SectionsBaseNames[8] = |
| { |
| "__objc_selectors", |
| "__objc_classes", |
| "__objc_class_refs", |
| "__objc_cats", |
| "__objc_protocols", |
| "__objc_protocol_refs", |
| "__objc_class_aliases", |
| "__objc_constant_string" |
| }; |
| |
| const char *const CGObjCGNUstep2::PECOFFSectionsBaseNames[8] = |
| { |
| ".objcrt$SEL", |
| ".objcrt$CLS", |
| ".objcrt$CLR", |
| ".objcrt$CAT", |
| ".objcrt$PCL", |
| ".objcrt$PCR", |
| ".objcrt$CAL", |
| ".objcrt$STR" |
| }; |
| |
| /// Support for the ObjFW runtime. |
| class CGObjCObjFW: public CGObjCGNU { |
| protected: |
| /// The GCC ABI message lookup function. Returns an IMP pointing to the |
| /// method implementation for this message. |
| LazyRuntimeFunction MsgLookupFn; |
| /// stret lookup function. While this does not seem to make sense at the |
| /// first look, this is required to call the correct forwarding function. |
| LazyRuntimeFunction MsgLookupFnSRet; |
| /// The GCC ABI superclass message lookup function. Takes a pointer to a |
| /// structure describing the receiver and the class, and a selector as |
| /// arguments. Returns the IMP for the corresponding method. |
| LazyRuntimeFunction MsgLookupSuperFn, MsgLookupSuperFnSRet; |
| |
| llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver, |
| llvm::Value *cmd, llvm::MDNode *node, |
| MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *args[] = { |
| EnforceType(Builder, Receiver, IdTy), |
| EnforceType(Builder, cmd, SelectorTy) }; |
| |
| llvm::CallBase *imp; |
| if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) |
| imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFnSRet, args); |
| else |
| imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args); |
| |
| imp->setMetadata(msgSendMDKind, node); |
| return imp; |
| } |
| |
| llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper, |
| llvm::Value *cmd, MessageSendInfo &MSI) override { |
| CGBuilderTy &Builder = CGF.Builder; |
| llvm::Value *lookupArgs[] = { |
| EnforceType(Builder, ObjCSuper.getPointer(), PtrToObjCSuperTy), cmd, |
| }; |
| |
| if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) |
| return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFnSRet, lookupArgs); |
| else |
| return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs); |
| } |
| |
| llvm::Value *GetClassNamed(CodeGenFunction &CGF, const std::string &Name, |
| bool isWeak) override { |
| if (isWeak) |
| return CGObjCGNU::GetClassNamed(CGF, Name, isWeak); |
| |
| EmitClassRef(Name); |
| std::string SymbolName = "_OBJC_CLASS_" + Name; |
| llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(SymbolName); |
| if (!ClassSymbol) |
| ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false, |
| llvm::GlobalValue::ExternalLinkage, |
| nullptr, SymbolName); |
| return ClassSymbol; |
| } |
| |
| public: |
| CGObjCObjFW(CodeGenModule &Mod): CGObjCGNU(Mod, 9, 3) { |
| // IMP objc_msg_lookup(id, SEL); |
| MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy); |
| MsgLookupFnSRet.init(&CGM, "objc_msg_lookup_stret", IMPTy, IdTy, |
| SelectorTy); |
| // IMP objc_msg_lookup_super(struct objc_super*, SEL); |
| MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy, |
| PtrToObjCSuperTy, SelectorTy); |
| MsgLookupSuperFnSRet.init(&CGM, "objc_msg_lookup_super_stret", IMPTy, |
| PtrToObjCSuperTy, SelectorTy); |
| } |
| }; |
| } // end anonymous namespace |
| |
| /// Emits a reference to a dummy variable which is emitted with each class. |
| /// This ensures that a linker error will be generated when trying to link |
| /// together modules where a referenced class is not defined. |
| void CGObjCGNU::EmitClassRef(const std::string &className) { |
| std::string symbolRef = "__objc_class_ref_" + className; |
| // Don't emit two copies of the same symbol |
| if (TheModule.getGlobalVariable(symbolRef)) |
| return; |
| std::string symbolName = "__objc_class_name_" + className; |
| llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(symbolName); |
| if (!ClassSymbol) { |
| ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false, |
| llvm::GlobalValue::ExternalLinkage, |
| nullptr, symbolName); |
| } |
| new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true, |
| llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef); |
| } |
| |
| CGObjCGNU::CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion, |
| unsigned protocolClassVersion, unsigned classABI) |
| : CGObjCRuntime(cgm), TheModule(CGM.getModule()), |
| VMContext(cgm.getLLVMContext()), ClassPtrAlias(nullptr), |
| MetaClassPtrAlias(nullptr), RuntimeVersion(runtimeABIVersion), |
| ProtocolVersion(protocolClassVersion), ClassABIVersion(classABI) { |
| |
| msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend"); |
| usesSEHExceptions = |
| cgm.getContext().getTargetInfo().getTriple().isWindowsMSVCEnvironment(); |
| |
| CodeGenTypes &Types = CGM.getTypes(); |
| IntTy = cast<llvm::IntegerType>( |
| Types.ConvertType(CGM.getContext().IntTy)); |
| LongTy = cast<llvm::IntegerType>( |
| Types.ConvertType(CGM.getContext().LongTy)); |
| SizeTy = cast<llvm::IntegerType>( |
| Types.ConvertType(CGM.getContext().getSizeType())); |
| PtrDiffTy = cast<llvm::IntegerType>( |
| Types.ConvertType(CGM.getContext().getPointerDiffType())); |
| BoolTy = CGM.getTypes().ConvertType(CGM.getContext().BoolTy); |
| |
| Int8Ty = llvm::Type::getInt8Ty(VMContext); |
| // C string type. Used in lots of places. |
| PtrToInt8Ty = llvm::PointerType::getUnqual(Int8Ty); |
| ProtocolPtrTy = llvm::PointerType::getUnqual( |
| Types.ConvertType(CGM.getContext().getObjCProtoType())); |
| |
| Zeros[0] = llvm::ConstantInt::get(LongTy, 0); |
| Zeros[1] = Zeros[0]; |
| NULLPtr = llvm::ConstantPointerNull::get(PtrToInt8Ty); |
| // Get the selector Type. |
| QualType selTy = CGM.getContext().getObjCSelType(); |
| if (QualType() == selTy) { |
| SelectorTy = PtrToInt8Ty; |
| } else { |
| SelectorTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(selTy)); |
| } |
| |
| PtrToIntTy = llvm::PointerType::getUnqual(IntTy); |
| PtrTy = PtrToInt8Ty; |
| |
| Int32Ty = llvm::Type::getInt32Ty(VMContext); |
| Int64Ty = llvm::Type::getInt64Ty(VMContext); |
| |
| IntPtrTy = |
| CGM.getDataLayout().getPointerSizeInBits() == 32 ? Int32Ty : Int64Ty; |
| |
| // Object type |
| QualType UnqualIdTy = CGM.getContext().getObjCIdType(); |
| ASTIdTy = CanQualType(); |
| if (UnqualIdTy != QualType()) { |
| ASTIdTy = CGM.getContext().getCanonicalType(UnqualIdTy); |
| IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy)); |
| } else { |
| IdTy = PtrToInt8Ty; |
| } |
| PtrToIdTy = llvm::PointerType::getUnqual(IdTy); |
| ProtocolTy = llvm::StructType::get(IdTy, |
| PtrToInt8Ty, // name |
| PtrToInt8Ty, // protocols |
| PtrToInt8Ty, // instance methods |
| PtrToInt8Ty, // class methods |
| PtrToInt8Ty, // optional instance methods |
| PtrToInt8Ty, // optional class methods |
| PtrToInt8Ty, // properties |
| PtrToInt8Ty);// optional properties |
| |
| // struct objc_property_gsv1 |
| // { |
| // const char *name; |
| // char attributes; |
| // char attributes2; |
| // char unused1; |
| // char unused2; |
| // const char *getter_name; |
| // const char *getter_types; |
| // const char *setter_name; |
| // const char *setter_types; |
| // } |
| PropertyMetadataTy = llvm::StructType::get(CGM.getLLVMContext(), { |
| PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, |
| PtrToInt8Ty, PtrToInt8Ty }); |
| |
| ObjCSuperTy = llvm::StructType::get(IdTy, IdTy); |
| PtrToObjCSuperTy = llvm::PointerType::getUnqual(ObjCSuperTy); |
| |
| llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext); |
| |
| // void objc_exception_throw(id); |
| ExceptionThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy); |
| ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy); |
| // int objc_sync_enter(id); |
| SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy); |
| // int objc_sync_exit(id); |
| SyncExitFn.init(&CGM, "objc_sync_exit", IntTy, IdTy); |
| |
| // void objc_enumerationMutation (id) |
| EnumerationMutationFn.init(&CGM, "objc_enumerationMutation", VoidTy, IdTy); |
| |
| // id objc_getProperty(id, SEL, ptrdiff_t, BOOL) |
| GetPropertyFn.init(&CGM, "objc_getProperty", IdTy, IdTy, SelectorTy, |
| PtrDiffTy, BoolTy); |
| // void objc_setProperty(id, SEL, ptrdiff_t, id, BOOL, BOOL) |
| SetPropertyFn.init(&CGM, "objc_setProperty", VoidTy, IdTy, SelectorTy, |
| PtrDiffTy, IdTy, BoolTy, BoolTy); |
| // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL) |
| GetStructPropertyFn.init(&CGM, "objc_getPropertyStruct", VoidTy, PtrTy, PtrTy, |
| PtrDiffTy, BoolTy, BoolTy); |
| // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL) |
| SetStructPropertyFn.init(&CGM, "objc_setPropertyStruct", VoidTy, PtrTy, PtrTy, |
| PtrDiffTy, BoolTy, BoolTy); |
| |
| // IMP type |
| llvm::Type *IMPArgs[] = { IdTy, SelectorTy }; |
| IMPTy = llvm::PointerType::getUnqual(llvm::FunctionType::get(IdTy, IMPArgs, |
| true)); |
| |
| const LangOptions &Opts = CGM.getLangOpts(); |
| if ((Opts.getGC() != LangOptions::NonGC) || Opts.ObjCAutoRefCount) |
| RuntimeVersion = 10; |
| |
| // Don't bother initialising the GC stuff unless we're compiling in GC mode |
| if (Opts.getGC() != LangOptions::NonGC) { |
| // This is a bit of an hack. We should sort this out by having a proper |
| // CGObjCGNUstep subclass for GC, but we may want to really support the old |
| // ABI and GC added in ObjectiveC2.framework, so we fudge it a bit for now |
| // Get selectors needed in GC mode |
| RetainSel = GetNullarySelector("retain", CGM.getContext()); |
| ReleaseSel = GetNullarySelector("release", CGM.getContext()); |
| AutoreleaseSel = GetNullarySelector("autorelease", CGM.getContext()); |
| |
| // Get functions needed in GC mode |
| |
| // id objc_assign_ivar(id, id, ptrdiff_t); |
| IvarAssignFn.init(&CGM, "objc_assign_ivar", IdTy, IdTy, IdTy, PtrDiffTy); |
| // id objc_assign_strongCast (id, id*) |
| StrongCastAssignFn.init(&CGM, "objc_assign_strongCast", IdTy, IdTy, |
| PtrToIdTy); |
| // id objc_assign_global(id, id*); |
| GlobalAssignFn.init(&CGM, "objc_assign_global", IdTy, IdTy, PtrToIdTy); |
| // id objc_assign_weak(id, id*); |
| WeakAssignFn.init(&CGM, "objc_assign_weak", IdTy, IdTy, PtrToIdTy); |
| // id objc_read_weak(id*); |
| WeakReadFn.init(&CGM, "objc_read_weak", IdTy, PtrToIdTy); |
| // void *objc_memmove_collectable(void*, void *, size_t); |
| MemMoveFn.init(&CGM, "objc_memmove_collectable", PtrTy, PtrTy, PtrTy, |
| SizeTy); |
| } |
| } |
| |
| llvm::Value *CGObjCGNU::GetClassNamed(CodeGenFunction &CGF, |
| const std::string &Name, bool isWeak) { |
| llvm::Constant *ClassName = MakeConstantString(Name); |
| // With the incompatible ABI, this will need to be replaced with a direct |
| // reference to the class symbol. For the compatible nonfragile ABI we are |
| // still performing this lookup at run time but emitting the symbol for the |
| // class externally so that we can make the switch later. |
| // |
| // Libobjc2 contains an LLVM pass that replaces calls to objc_lookup_class |
| // with memoized versions or with static references if it's safe to do so. |
| if (!isWeak) |
| EmitClassRef(Name); |
| |
| llvm::FunctionCallee ClassLookupFn = CGM.CreateRuntimeFunction( |
| llvm::FunctionType::get(IdTy, PtrToInt8Ty, true), "objc_lookup_class"); |
| return CGF.EmitNounwindRuntimeCall(ClassLookupFn, ClassName); |
| } |
| |
| // This has to perform the lookup every time, since posing and related |
| // techniques can modify the name -> class mapping. |
| llvm::Value *CGObjCGNU::GetClass(CodeGenFunction &CGF, |
| const ObjCInterfaceDecl *OID) { |
| auto *Value = |
| GetClassNamed(CGF, OID->getNameAsString(), OID->isWeakImported()); |
| if (auto *ClassSymbol = dyn_cast<llvm::GlobalVariable>(Value)) |
| CGM.setGVProperties(ClassSymbol, OID); |
| return Value; |
| } |
| |
| llvm::Value *CGObjCGNU::EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) { |
| auto *Value = GetClassNamed(CGF, "NSAutoreleasePool", false); |
| if (CGM.getTriple().isOSBinFormatCOFF()) { |
| if (auto *ClassSymbol = dyn_cast<llvm::GlobalVariable>(Value)) { |
| IdentifierInfo &II = CGF.CGM.getContext().Idents.get("NSAutoreleasePool"); |
| TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl(); |
| DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); |
| |
| const VarDecl *VD = nullptr; |
| for (const auto &Result : DC->lookup(&II)) |
| if ((VD = dyn_cast<VarDecl>(Result))) |
| break; |
| |
| CGM.setGVProperties(ClassSymbol, VD); |
| } |
| } |
| return Value; |
| } |
| |
| llvm::Value *CGObjCGNU::GetTypedSelector(CodeGenFunction &CGF, Selector Sel, |
| const std::string &TypeEncoding) { |
| SmallVectorImpl<TypedSelector> &Types = SelectorTable[Sel]; |
| llvm::GlobalAlias *SelValue = nullptr; |
| |
| for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(), |
| e = Types.end() ; i!=e ; i++) { |
| if (i->first == TypeEncoding) { |
| SelValue = i->second; |
| break; |
| } |
| } |
| if (!SelValue) { |
| SelValue = llvm::GlobalAlias::create( |
| SelectorTy->getElementType(), 0, llvm::GlobalValue::PrivateLinkage, |
| ".objc_selector_" + Sel.getAsString(), &TheModule); |
| Types.emplace_back(TypeEncoding, SelValue); |
| } |
| |
| return SelValue; |
| } |
| |
| Address CGObjCGNU::GetAddrOfSelector(CodeGenFunction &CGF, Selector Sel) { |
| llvm::Value *SelValue = GetSelector(CGF, Sel); |
| |
| // Store it to a temporary. Does this satisfy the semantics of |
| // GetAddrOfSelector? Hopefully. |
| Address tmp = CGF.CreateTempAlloca(SelValue->getType(), |
| CGF.getPointerAlign()); |
| CGF.Builder.CreateStore(SelValue, tmp); |
| return tmp; |
| } |
| |
| llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF, Selector Sel) { |
| return GetTypedSelector(CGF, Sel, std::string()); |
| } |
| |
| llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF, |
| const ObjCMethodDecl *Method) { |
| std::string SelTypes = CGM.getContext().getObjCEncodingForMethodDecl(Method); |
| return GetTypedSelector(CGF, Method->getSelector(), SelTypes); |
| } |
| |
| llvm::Constant *CGObjCGNU::GetEHType(QualType T) { |
| if (T->isObjCIdType() || T->isObjCQualifiedIdType()) { |
| // With the old ABI, there was only one kind of catchall, which broke |
| // foreign exceptions. With the new ABI, we use __objc_id_typeinfo as |
| // a pointer indicating object catchalls, and NULL to indicate real |
| // catchalls |
| if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) { |
| return MakeConstantString("@id"); |
| } else { |
| return nullptr; |
| } |
| } |
| |
| // All other types should be Objective-C interface pointer types. |
| const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>(); |
| assert(OPT && "Invalid @catch type."); |
| const ObjCInterfaceDecl *IDecl = OPT->getObjectType()->getInterface(); |
| assert(IDecl && "Invalid @catch type."); |
| return MakeConstantString(IDecl->getIdentifier()->getName()); |
| } |
| |
| llvm::Constant *CGObjCGNUstep::GetEHType(QualType T) { |
| if (usesSEHExceptions) |
| return CGM.getCXXABI().getAddrOfRTTIDescriptor(T); |
| |
| if (!CGM.getLangOpts().CPlusPlus) |
| return CGObjCGNU::GetEHType(T); |
| |
| // For Objective-C++, we want to provide the ability to catch both C++ and |
| // Objective-C objects in the same function. |
| |
| // There's a particular fixed type info for 'id'. |
| if (T->isObjCIdType() || |
| T->isObjCQualifiedIdType()) { |
| llvm::Constant *IDEHType = |
| CGM.getModule().getGlobalVariable("__objc_id_type_info"); |
| if (!IDEHType) |
| IDEHType = |
| new llvm::GlobalVariable(CGM.getModule(), PtrToInt8Ty, |
| false, |
| llvm::GlobalValue::ExternalLinkage, |
| nullptr, "__objc_id_type_info"); |
| return llvm::ConstantExpr::getBitCast(IDEHType, PtrToInt8Ty); |
| } |
| |
| const ObjCObjectPointerType *PT = |
| T->getAs<ObjCObjectPointerType>(); |
| assert(PT && "Invalid @catch type."); |
| const ObjCInterfaceType *IT = PT->getInterfaceType(); |
| assert(IT && "Invalid @catch type."); |
| std::string className = |
| std::string(IT->getDecl()->getIdentifier()->getName()); |
| |
| std::string typeinfoName = "__objc_eh_typeinfo_" + className; |
| |
| // Return the existing typeinfo if it exists |
| llvm::Constant *typeinfo = TheModule.getGlobalVariable(typeinfoName); |
| if (typeinfo) |
| return llvm::ConstantExpr::getBitCast(typeinfo, PtrToInt8Ty); |
| |
| // Otherwise create it. |
| |
| // vtable for gnustep::libobjc::__objc_class_type_info |
| // It's quite ugly hard-coding this. Ideally we'd generate it using the host |
| // platform's name mangling. |
| const char *vtableName = "_ZTVN7gnustep7libobjc22__objc_class_type_infoE"; |
| auto *Vtable = TheModule.getGlobalVariable(vtableName); |
| if (!Vtable) { |
| Vtable = new llvm::GlobalVariable(TheModule, PtrToInt8Ty, true, |
| llvm::GlobalValue::ExternalLinkage, |
| nullptr, vtableName); |
| } |
| llvm::Constant *Two = llvm::ConstantInt::get(IntTy, 2); |
| auto *BVtable = llvm::ConstantExpr::getBitCast( |
| llvm::ConstantExpr::getGetElementPtr(Vtable->getValueType(), Vtable, Two), |
| PtrToInt8Ty); |
| |
| llvm::Constant *typeName = |
| ExportUniqueString(className, "__objc_eh_typename_"); |
| |
| ConstantInitBuilder builder(CGM); |
| auto fields = builder.beginStruct(); |
| fields.add(BVtable); |
| fields.add(typeName); |
| llvm::Constant *TI = |
| fields.finishAndCreateGlobal("__objc_eh_typeinfo_" + className, |
| CGM.getPointerAlign(), |
| /*constant*/ false, |
| llvm::GlobalValue::LinkOnceODRLinkage); |
| return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty); |
| } |
| |
| /// Generate an NSConstantString object. |
| ConstantAddress CGObjCGNU::GenerateConstantString(const StringLiteral *SL) { |
| |
| std::string Str = SL->getString().str(); |
| CharUnits Align = CGM.getPointerAlign(); |
| |
| // Look for an existing one |
| llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str); |
| if (old != ObjCStrings.end()) |
| return ConstantAddress(old->getValue(), Align); |
| |
| StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass; |
| |
| if (StringClass.empty()) StringClass = "NSConstantString"; |
| |
| std::string Sym = "_OBJC_CLASS_"; |
| Sym += StringClass; |
| |
| llvm::Constant *isa = TheModule.getNamedGlobal(Sym); |
| |
| if (!isa) |
| isa = new llvm::GlobalVariable(TheModule, IdTy, /* isConstant */false, |
| llvm::GlobalValue::ExternalWeakLinkage, nullptr, Sym); |
| else if (isa->getType() != PtrToIdTy) |
| isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy); |
| |
| ConstantInitBuilder Builder(CGM); |
| auto Fields = Builder.beginStruct(); |
| Fields.add(isa); |
| Fields.add(MakeConstantString(Str)); |
| Fields.addInt(IntTy, Str.size()); |
| llvm::Constant *ObjCStr = |
| Fields.finishAndCreateGlobal(".objc_str", Align); |
| ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty); |
| ObjCStrings[Str] = ObjCStr; |
| ConstantStrings.push_back(ObjCStr); |
| return ConstantAddress(ObjCStr, Align); |
| } |
| |
| ///Generates a message send where the super is the receiver. This is a message |
| ///send to self with special delivery semantics indicating which class's method |
| ///should be called. |
| RValue |
| CGObjCGNU::GenerateMessageSendSuper(CodeGenFunction &CGF, |
| ReturnValueSlot Return, |
| QualType ResultType, |
| Selector Sel, |
| const ObjCInterfaceDecl *Class, |
| bool isCategoryImpl, |
| llvm::Value *Receiver, |
| bool IsClassMessage, |
| const CallArgList &CallArgs, |
| const ObjCMethodDecl *Method) { |
| CGBuilderTy &Builder = CGF.Builder; |
| if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) { |
| if (Sel == RetainSel || Sel == AutoreleaseSel) { |
| return RValue::get(EnforceType(Builder, Receiver, |
| CGM.getTypes().ConvertType(ResultType))); |
| } |
| if (Sel == ReleaseSel) { |
| return RValue::get(nullptr); |
| } |
| } |
| |
| llvm::Value *cmd = GetSelector(CGF, Sel); |
| CallArgList ActualArgs; |
| |
| ActualArgs.add(RValue::get(EnforceType(Builder, Receiver, IdTy)), ASTIdTy); |
| ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType()); |
| ActualArgs.addFrom(CallArgs); |
| |
| MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs); |
| |
| llvm::Value *ReceiverClass = nullptr; |
| bool isV2ABI = isRuntime(ObjCRuntime::GNUstep, 2); |
| if (isV2ABI) { |
| ReceiverClass = GetClassNamed(CGF, |
| Class->getSuperClass()->getNameAsString(), /*isWeak*/false); |
| if (IsClassMessage) { |
| // Load the isa pointer of the superclass is this is a class method. |
| ReceiverClass = Builder.CreateBitCast(ReceiverClass, |
| llvm::PointerType::getUnqual(IdTy)); |
| ReceiverClass = |
| Builder.CreateAlignedLoad(ReceiverClass, CGF.getPointerAlign()); |
| } |
| ReceiverClass = EnforceType(Builder, ReceiverClass, IdTy); |
| } else { |
| if (isCategoryImpl) { |
| llvm::FunctionCallee classLookupFunction = nullptr; |
| if (IsClassMessage) { |
| classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get( |
| IdTy, PtrTy, true), "objc_get_meta_class"); |
| } else { |
| classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get( |
| IdTy, PtrTy, true), "objc_get_class"); |
| } |
| ReceiverClass = Builder.CreateCall(classLookupFunction, |
| MakeConstantString(Class->getNameAsString())); |
| } else { |
| // Set up global aliases for the metaclass or class pointer if they do not |
| // already exist. These will are forward-references which will be set to |
| // pointers to the class and metaclass structure created for the runtime |
| // load function. To send a message to super, we look up the value of the |
| // super_class pointer from either the class or metaclass structure. |
| if (IsClassMessage) { |
| if (!MetaClassPtrAlias) { |
| MetaClassPtrAlias = llvm::GlobalAlias::create( |
| IdTy->getElementType(), 0, llvm::GlobalValue::InternalLinkage, |
| ".objc_metaclass_ref" + Class->getNameAsString(), &TheModule); |
| } |
| ReceiverClass = MetaClassPtrAlias; |
| } else { |
| if (!ClassPtrAlias) { |
| ClassPtrAlias = llvm::GlobalAlias::create( |
| IdTy->getElementType(), 0, llvm::GlobalValue::InternalLinkage, |
| ".objc_class_ref" + Class->getNameAsString(), &TheModule); |
| } |
| ReceiverClass = ClassPtrAlias; |
| } |
| } |
| // Cast the pointer to a simplified version of the class structure |
| llvm::Type *CastTy = llvm::StructType::get(IdTy, IdTy); |
| ReceiverClass = Builder.CreateBitCast(ReceiverClass, |
| llvm::PointerType::getUnqual(CastTy)); |
| // Get the superclass pointer |
| ReceiverClass = Builder.CreateStructGEP(CastTy, ReceiverClass, 1); |
| // Load the superclass pointer |
| ReceiverClass = |
| Builder.CreateAlignedLoad(ReceiverClass, CGF.getPointerAlign()); |
| } |
| // Construct the structure used to look up the IMP |
| llvm
|