Current Path : /compat/linux/proc/68247/root/usr/src/contrib/llvm/tools/clang/lib/CodeGen/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //compat/linux/proc/68247/root/usr/src/contrib/llvm/tools/clang/lib/CodeGen/CGObjCGNU.cpp |
//===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // 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 "CGObjCRuntime.h" #include "CodeGenModule.h" #include "CodeGenFunction.h" #include "CGCleanup.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Decl.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/RecordLayout.h" #include "clang/AST/StmtObjC.h" #include "clang/Basic/SourceManager.h" #include "clang/Basic/FileManager.h" #include "llvm/Intrinsics.h" #include "llvm/Module.h" #include "llvm/LLVMContext.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/StringMap.h" #include "llvm/Support/CallSite.h" #include "llvm/Support/Compiler.h" #include "llvm/Target/TargetData.h" #include <cstdarg> using namespace clang; using namespace CodeGen; namespace { /// 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; std::vector<llvm::Type*> ArgTys; const char *FunctionName; llvm::Constant *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(0), FunctionName(0), Function(0) {} /// Initialises the lazy function with the name, return type, and the types /// of the arguments. END_WITH_NULL void init(CodeGenModule *Mod, const char *name, llvm::Type *RetTy, ...) { CGM =Mod; FunctionName = name; Function = 0; ArgTys.clear(); va_list Args; va_start(Args, RetTy); while (llvm::Type *ArgTy = va_arg(Args, llvm::Type*)) ArgTys.push_back(ArgTy); va_end(Args); // Push the return type on at the end so we can pop it off easily ArgTys.push_back(RetTy); } /// Overloaded cast operator, allows the class to be implicitly cast to an /// LLVM constant. operator llvm::Constant*() { if (!Function) { if (0 == FunctionName) return 0; // We put the return type on the end of the vector, so pop it back off llvm::Type *RetTy = ArgTys.back(); ArgTys.pop_back(); llvm::FunctionType *FTy = llvm::FunctionType::get(RetTy, ArgTys, false); Function = cast<llvm::Constant>(CGM->CreateRuntimeFunction(FTy, FunctionName)); // We won't need to use the types again, so we may as well clean up the // vector now ArgTys.resize(0); } return Function; } operator llvm::Function*() { return cast<llvm::Function>((llvm::Constant*)*this); } }; /// 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 and /// GNUstep). 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; /// 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; /// 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; /// 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(const std::string &Str, const std::string &Name="") { llvm::Constant *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str()); return llvm::ConstantExpr::getGetElementPtr(ConstStr, 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) { std::string name = prefix + Str; llvm::Constant *ConstStr = TheModule.getGlobalVariable(name); if (!ConstStr) { llvm::Constant *value = llvm::ConstantDataArray::getString(VMContext,Str); ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true, llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str); } return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros); } /// Generates a global structure, initialized by the elements in the vector. /// The element types must match the types of the structure elements in the /// first argument. llvm::GlobalVariable *MakeGlobal(llvm::StructType *Ty, llvm::ArrayRef<llvm::Constant*> V, StringRef Name="", llvm::GlobalValue::LinkageTypes linkage =llvm::GlobalValue::InternalLinkage) { llvm::Constant *C = llvm::ConstantStruct::get(Ty, V); return new llvm::GlobalVariable(TheModule, Ty, false, linkage, C, Name); } /// Generates a global array. The vector must contain the same number of /// elements that the array type declares, of the type specified as the array /// element type. llvm::GlobalVariable *MakeGlobal(llvm::ArrayType *Ty, llvm::ArrayRef<llvm::Constant*> V, StringRef Name="", llvm::GlobalValue::LinkageTypes linkage =llvm::GlobalValue::InternalLinkage) { llvm::Constant *C = llvm::ConstantArray::get(Ty, V); return new llvm::GlobalVariable(TheModule, Ty, false, linkage, C, Name); } /// Generates a global array, inferring the array type from the specified /// element type and the size of the initialiser. llvm::GlobalVariable *MakeGlobalArray(llvm::Type *Ty, llvm::ArrayRef<llvm::Constant*> V, StringRef Name="", llvm::GlobalValue::LinkageTypes linkage =llvm::GlobalValue::InternalLinkage) { llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size()); return MakeGlobal(ArrayTy, V, Name, linkage); } /// 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); } // 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; private: /// 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; /// 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; private: /// 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. llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames, ArrayRef<llvm::Constant *> IvarTypes, ArrayRef<llvm::Constant *> IvarOffsets); /// 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(const StringRef &ClassName, const StringRef &CategoryName, ArrayRef<Selector> MethodSels, ArrayRef<llvm::Constant *> MethodTypes, 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. llvm::Constant *GenerateEmptyProtocol(const std::string &ProtocolName); /// Generates a list of property metadata structures. This follows the same /// pattern as method and instance variable metadata lists. llvm::Constant *GeneratePropertyList(const ObjCImplementationDecl *OID, SmallVectorImpl<Selector> &InstanceMethodSels, SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes); /// 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(void); /// 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. llvm::Constant *GenerateProtocolMethodList( ArrayRef<llvm::Constant *> MethodNames, ArrayRef<llvm::Constant *> MethodTypes); /// 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). llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel, const std::string &TypeEncoding, bool lval); /// 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 llvm::Value *GetClassNamed(CGBuilderTy &Builder, const std::string &Name, bool isWeak); protected: /// 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) = 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, llvm::Value *ObjCSuper, llvm::Value *cmd) = 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); virtual llvm::Constant *GenerateConstantString(const StringLiteral *); virtual RValue GenerateMessageSend(CodeGenFunction &CGF, ReturnValueSlot Return, QualType ResultType, Selector Sel, llvm::Value *Receiver, const CallArgList &CallArgs, const ObjCInterfaceDecl *Class, const ObjCMethodDecl *Method); virtual 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); virtual llvm::Value *GetClass(CGBuilderTy &Builder, const ObjCInterfaceDecl *OID); virtual llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel, bool lval = false); virtual llvm::Value *GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl *Method); virtual llvm::Constant *GetEHType(QualType T); virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD, const ObjCContainerDecl *CD); virtual void GenerateCategory(const ObjCCategoryImplDecl *CMD); virtual void GenerateClass(const ObjCImplementationDecl *ClassDecl); virtual void RegisterAlias(const ObjCCompatibleAliasDecl *OAD); virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder, const ObjCProtocolDecl *PD); virtual void GenerateProtocol(const ObjCProtocolDecl *PD); virtual llvm::Function *ModuleInitFunction(); virtual llvm::Constant *GetPropertyGetFunction(); virtual llvm::Constant *GetPropertySetFunction(); virtual llvm::Constant *GetOptimizedPropertySetFunction(bool atomic, bool copy); virtual llvm::Constant *GetSetStructFunction(); virtual llvm::Constant *GetCppAtomicObjectFunction(); virtual llvm::Constant *GetGetStructFunction(); virtual llvm::Constant *EnumerationMutationFunction(); virtual void EmitTryStmt(CodeGenFunction &CGF, const ObjCAtTryStmt &S); virtual void EmitSynchronizedStmt(CodeGenFunction &CGF, const ObjCAtSynchronizedStmt &S); virtual void EmitThrowStmt(CodeGenFunction &CGF, const ObjCAtThrowStmt &S); virtual llvm::Value * EmitObjCWeakRead(CodeGenFunction &CGF, llvm::Value *AddrWeakObj); virtual void EmitObjCWeakAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dst); virtual void EmitObjCGlobalAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dest, bool threadlocal=false); virtual void EmitObjCIvarAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dest, llvm::Value *ivarOffset); virtual void EmitObjCStrongCastAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dest); virtual void EmitGCMemmoveCollectable(CodeGenFunction &CGF, llvm::Value *DestPtr, llvm::Value *SrcPtr, llvm::Value *Size); virtual LValue EmitObjCValueForIvar(CodeGenFunction &CGF, QualType ObjectTy, llvm::Value *BaseValue, const ObjCIvarDecl *Ivar, unsigned CVRQualifiers); virtual llvm::Value *EmitIvarOffset(CodeGenFunction &CGF, const ObjCInterfaceDecl *Interface, const ObjCIvarDecl *Ivar); virtual llvm::Value *EmitNSAutoreleasePoolClassRef(CGBuilderTy &Builder); virtual llvm::Constant *BuildGCBlockLayout(CodeGenModule &CGM, const CGBlockInfo &blockInfo) { return NULLPtr; } virtual llvm::GlobalVariable *GetClassGlobal(const std::string &Name) { return 0; } }; /// 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: virtual llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver, llvm::Value *cmd, llvm::MDNode *node) { CGBuilderTy &Builder = CGF.Builder; llvm::Value *args[] = { EnforceType(Builder, Receiver, IdTy), EnforceType(Builder, cmd, SelectorTy) }; llvm::CallSite imp = CGF.EmitCallOrInvoke(MsgLookupFn, args); imp->setMetadata(msgSendMDKind, node); return imp.getInstruction(); } virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, llvm::Value *ObjCSuper, llvm::Value *cmd) { CGBuilderTy &Builder = CGF.Builder; llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper, PtrToObjCSuperTy), cmd}; return Builder.CreateCall(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, NULL); // IMP objc_msg_lookup_super(struct objc_super*, SEL); MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy, PtrToObjCSuperTy, SelectorTy, NULL); } }; /// 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; /// Type of an slot structure pointer. This is returned by the various /// lookup functions. llvm::Type *SlotTy; protected: virtual llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver, llvm::Value *cmd, llvm::MDNode *node) { CGBuilderTy &Builder = CGF.Builder; llvm::Function *LookupFn = SlotLookupFn; // Store the receiver on the stack so that we can reload it later llvm::Value *ReceiverPtr = CGF.CreateTempAlloca(Receiver->getType()); 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. LookupFn->setDoesNotCapture(1); llvm::Value *args[] = { EnforceType(Builder, ReceiverPtr, PtrToIdTy), EnforceType(Builder, cmd, SelectorTy), EnforceType(Builder, self, IdTy) }; llvm::CallSite slot = CGF.EmitCallOrInvoke(LookupFn, args); slot.setOnlyReadsMemory(); slot->setMetadata(msgSendMDKind, node); // Load the imp from the slot llvm::Value *imp = Builder.CreateLoad(Builder.CreateStructGEP(slot.getInstruction(), 4)); // The lookup function may have changed the receiver, so make sure we use // the new one. Receiver = Builder.CreateLoad(ReceiverPtr, true); return imp; } virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, llvm::Value *ObjCSuper, llvm::Value *cmd) { CGBuilderTy &Builder = CGF.Builder; llvm::Value *lookupArgs[] = {ObjCSuper, cmd}; llvm::CallInst *slot = Builder.CreateCall(SlotLookupSuperFn, lookupArgs); slot->setOnlyReadsMemory(); return Builder.CreateLoad(Builder.CreateStructGEP(slot, 4)); } public: CGObjCGNUstep(CodeGenModule &Mod) : CGObjCGNU(Mod, 9, 3) { llvm::StructType *SlotStructTy = llvm::StructType::get(PtrTy, PtrTy, PtrTy, IntTy, IMPTy, NULL); 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, NULL); // Slot_t objc_msg_lookup_super(struct objc_super*, SEL); SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy, PtrToObjCSuperTy, SelectorTy, NULL); // If we're in ObjC++ mode, then we want to make 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, NULL); // void __cxa_end_catch(void) ExitCatchFn.init(&CGM, "__cxa_end_catch", VoidTy, NULL); // void _Unwind_Resume_or_Rethrow(void*) ExceptionReThrowFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy, PtrTy, NULL); } } }; } // 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, 0, symbolName); } new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true, llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef); } static std::string SymbolNameForMethod(const StringRef &ClassName, const 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(); } CGObjCGNU::CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion, unsigned protocolClassVersion) : CGObjCRuntime(cgm), TheModule(CGM.getModule()), VMContext(cgm.getLLVMContext()), ClassPtrAlias(0), MetaClassPtrAlias(0), RuntimeVersion(runtimeABIVersion), ProtocolVersion(protocolClassVersion) { msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend"); 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); 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 = TheModule.getPointerSize() == llvm::Module::Pointer32 ? 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); ObjCSuperTy = llvm::StructType::get(IdTy, IdTy, NULL); 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, NULL); ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, NULL); // int objc_sync_enter(id); SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy, NULL); // int objc_sync_exit(id); SyncExitFn.init(&CGM, "objc_sync_exit", IntTy, IdTy, NULL); // void objc_enumerationMutation (id) EnumerationMutationFn.init(&CGM, "objc_enumerationMutation", VoidTy, IdTy, NULL); // id objc_getProperty(id, SEL, ptrdiff_t, BOOL) GetPropertyFn.init(&CGM, "objc_getProperty", IdTy, IdTy, SelectorTy, PtrDiffTy, BoolTy, NULL); // void objc_setProperty(id, SEL, ptrdiff_t, id, BOOL, BOOL) SetPropertyFn.init(&CGM, "objc_setProperty", VoidTy, IdTy, SelectorTy, PtrDiffTy, IdTy, BoolTy, BoolTy, NULL); // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL) GetStructPropertyFn.init(&CGM, "objc_getPropertyStruct", VoidTy, PtrTy, PtrTy, PtrDiffTy, BoolTy, BoolTy, NULL); // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL) SetStructPropertyFn.init(&CGM, "objc_setPropertyStruct", VoidTy, PtrTy, PtrTy, PtrDiffTy, BoolTy, BoolTy, NULL); // 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, NULL); // id objc_assign_strongCast (id, id*) StrongCastAssignFn.init(&CGM, "objc_assign_strongCast", IdTy, IdTy, PtrToIdTy, NULL); // id objc_assign_global(id, id*); GlobalAssignFn.init(&CGM, "objc_assign_global", IdTy, IdTy, PtrToIdTy, NULL); // id objc_assign_weak(id, id*); WeakAssignFn.init(&CGM, "objc_assign_weak", IdTy, IdTy, PtrToIdTy, NULL); // id objc_read_weak(id*); WeakReadFn.init(&CGM, "objc_read_weak", IdTy, PtrToIdTy, NULL); // void *objc_memmove_collectable(void*, void *, size_t); MemMoveFn.init(&CGM, "objc_memmove_collectable", PtrTy, PtrTy, PtrTy, SizeTy, NULL); } } llvm::Value *CGObjCGNU::GetClassNamed(CGBuilderTy &Builder, const std::string &Name, bool isWeak) { llvm::Value *ClassName = CGM.GetAddrOfConstantCString(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); ClassName = Builder.CreateStructGEP(ClassName, 0); llvm::Constant *ClassLookupFn = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, PtrToInt8Ty, true), "objc_lookup_class"); return Builder.CreateCall(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(CGBuilderTy &Builder, const ObjCInterfaceDecl *OID) { return GetClassNamed(Builder, OID->getNameAsString(), OID->isWeakImported()); } llvm::Value *CGObjCGNU::EmitNSAutoreleasePoolClassRef(CGBuilderTy &Builder) { return GetClassNamed(Builder, "NSAutoreleasePool", false); } llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel, const std::string &TypeEncoding, bool lval) { SmallVector<TypedSelector, 2> &Types = SelectorTable[Sel]; llvm::GlobalAlias *SelValue = 0; for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(), e = Types.end() ; i!=e ; i++) { if (i->first == TypeEncoding) { SelValue = i->second; break; } } if (0 == SelValue) { SelValue = new llvm::GlobalAlias(SelectorTy, llvm::GlobalValue::PrivateLinkage, ".objc_selector_"+Sel.getAsString(), NULL, &TheModule); Types.push_back(TypedSelector(TypeEncoding, SelValue)); } if (lval) { llvm::Value *tmp = Builder.CreateAlloca(SelValue->getType()); Builder.CreateStore(SelValue, tmp); return tmp; } return SelValue; } llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel, bool lval) { return GetSelector(Builder, Sel, std::string(), lval); } llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl *Method) { std::string SelTypes; CGM.getContext().getObjCEncodingForMethodDecl(Method, SelTypes); return GetSelector(Builder, Method->getSelector(), SelTypes, false); } llvm::Constant *CGObjCGNU::GetEHType(QualType T) { if (!CGM.getLangOpts().CPlusPlus) { 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().ObjCNonFragileABI) { return MakeConstantString("@id"); } else { return 0; } } // 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()); } // 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, 0, "__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 = 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"; llvm::Constant *Vtable = TheModule.getGlobalVariable(vtableName); if (!Vtable) { Vtable = new llvm::GlobalVariable(TheModule, PtrToInt8Ty, true, llvm::GlobalValue::ExternalLinkage, 0, vtableName); } llvm::Constant *Two = llvm::ConstantInt::get(IntTy, 2); Vtable = llvm::ConstantExpr::getGetElementPtr(Vtable, Two); Vtable = llvm::ConstantExpr::getBitCast(Vtable, PtrToInt8Ty); llvm::Constant *typeName = ExportUniqueString(className, "__objc_eh_typename_"); std::vector<llvm::Constant*> fields; fields.push_back(Vtable); fields.push_back(typeName); llvm::Constant *TI = MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, NULL), fields, "__objc_eh_typeinfo_" + className, llvm::GlobalValue::LinkOnceODRLinkage); return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty); } /// Generate an NSConstantString object. llvm::Constant *CGObjCGNU::GenerateConstantString(const StringLiteral *SL) { std::string Str = SL->getString().str(); // Look for an existing one llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str); if (old != ObjCStrings.end()) return old->getValue(); StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass; if (StringClass.empty()) StringClass = "NXConstantString"; 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, 0, Sym); else if (isa->getType() != PtrToIdTy) isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy); std::vector<llvm::Constant*> Ivars; Ivars.push_back(isa); Ivars.push_back(MakeConstantString(Str)); Ivars.push_back(llvm::ConstantInt::get(IntTy, Str.size())); llvm::Constant *ObjCStr = MakeGlobal( llvm::StructType::get(PtrToIdTy, PtrToInt8Ty, IntTy, NULL), Ivars, ".objc_str"); ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty); ObjCStrings[Str] = ObjCStr; ConstantStrings.push_back(ObjCStr); return ObjCStr; } ///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(0); } } llvm::Value *cmd = GetSelector(Builder, 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 = 0; if (isCategoryImpl) { llvm::Constant *classLookupFunction = 0; 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 = new llvm::GlobalAlias(IdTy, llvm::GlobalValue::InternalLinkage, ".objc_metaclass_ref" + Class->getNameAsString(), NULL, &TheModule); } ReceiverClass = MetaClassPtrAlias; } else { if (!ClassPtrAlias) { ClassPtrAlias = new llvm::GlobalAlias(IdTy, llvm::GlobalValue::InternalLinkage, ".objc_class_ref" + Class->getNameAsString(), NULL, &TheModule); } ReceiverClass = ClassPtrAlias; } } // Cast the pointer to a simplified version of the class structure ReceiverClass = Builder.CreateBitCast(ReceiverClass, llvm::PointerType::getUnqual( llvm::StructType::get(IdTy, IdTy, NULL))); // Get the superclass pointer ReceiverClass = Builder.CreateStructGEP(ReceiverClass, 1); // Load the superclass pointer ReceiverClass = Builder.CreateLoad(ReceiverClass); // Construct the structure used to look up the IMP llvm::StructType *ObjCSuperTy = llvm::StructType::get( Receiver->getType(), IdTy, NULL); llvm::Value *ObjCSuper = Builder.CreateAlloca(ObjCSuperTy); Builder.CreateStore(Receiver, Builder.CreateStructGEP(ObjCSuper, 0)); Builder.CreateStore(ReceiverClass, Builder.CreateStructGEP(ObjCSuper, 1)); ObjCSuper = EnforceType(Builder, ObjCSuper, PtrToObjCSuperTy); // Get the IMP llvm::Value *imp = LookupIMPSuper(CGF, ObjCSuper, cmd); imp = EnforceType(Builder, imp, MSI.MessengerType); llvm::Value *impMD[] = { llvm::MDString::get(VMContext, Sel.getAsString()), llvm::MDString::get(VMContext, Class->getSuperClass()->getNameAsString()), llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), IsClassMessage) }; llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD); llvm::Instruction *call; RValue msgRet = CGF.EmitCall(MSI.CallInfo, imp, Return, ActualArgs, 0, &call); call->setMetadata(msgSendMDKind, node); return msgRet; } /// Generate code for a message send expression. RValue CGObjCGNU::GenerateMessageSend(CodeGenFunction &CGF, ReturnValueSlot Return, QualType ResultType, Selector Sel, llvm::Value *Receiver, const CallArgList &CallArgs, const ObjCInterfaceDecl *Class, const ObjCMethodDecl *Method) { CGBuilderTy &Builder = CGF.Builder; // Strip out message sends to retain / release in GC mode 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(0); } } // If the return type is something that goes in an integer register, the // runtime will handle 0 returns. For other cases, we fill in the 0 value // ourselves. // // The language spec says the result of this kind of message send is // undefined, but lots of people seem to have forgotten to read that // paragraph and insist on sending messages to nil that have structure // returns. With GCC, this generates a random return value (whatever happens // to be on the stack / in those registers at the time) on most platforms, // and generates an illegal instruction trap on SPARC. With LLVM it corrupts // the stack. bool isPointerSizedReturn = (ResultType->isAnyPointerType() || ResultType->isIntegralOrEnumerationType() || ResultType->isVoidType()); llvm::BasicBlock *startBB = 0; llvm::BasicBlock *messageBB = 0; llvm::BasicBlock *continueBB = 0; if (!isPointerSizedReturn) { startBB = Builder.GetInsertBlock(); messageBB = CGF.createBasicBlock("msgSend"); continueBB = CGF.createBasicBlock("continue"); llvm::Value *isNil = Builder.CreateICmpEQ(Receiver, llvm::Constant::getNullValue(Receiver->getType())); Builder.CreateCondBr(isNil, continueBB, messageBB); CGF.EmitBlock(messageBB); } IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy)); llvm::Value *cmd; if (Method) cmd = GetSelector(Builder, Method); else cmd = GetSelector(Builder, Sel); cmd = EnforceType(Builder, cmd, SelectorTy); Receiver = EnforceType(Builder, Receiver, IdTy); llvm::Value *impMD[] = { llvm::MDString::get(VMContext, Sel.getAsString()), llvm::MDString::get(VMContext, Class ? Class->getNameAsString() :""), llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), Class!=0) }; llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD); CallArgList ActualArgs; ActualArgs.add(RValue::get(Receiver), ASTIdTy); ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType()); ActualArgs.addFrom(CallArgs); MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs); // Get the IMP to call llvm::Value *imp; // If we have non-legacy dispatch specified, we try using the objc_msgSend() // functions. These are not supported on all platforms (or all runtimes on a // given platform), so we switch (CGM.getCodeGenOpts().getObjCDispatchMethod()) { case CodeGenOptions::Legacy: imp = LookupIMP(CGF, Receiver, cmd, node); break; case CodeGenOptions::Mixed: case CodeGenOptions::NonLegacy: if (CGM.ReturnTypeUsesFPRet(ResultType)) { imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true), "objc_msgSend_fpret"); } else if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) { // The actual types here don't matter - we're going to bitcast the // function anyway imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true), "objc_msgSend_stret"); } else { imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true), "objc_msgSend"); } } // Reset the receiver in case the lookup modified it ActualArgs[0] = CallArg(RValue::get(Receiver), ASTIdTy, false); imp = EnforceType(Builder, imp, MSI.MessengerType); llvm::Instruction *call; RValue msgRet = CGF.EmitCall(MSI.CallInfo, imp, Return, ActualArgs, 0, &call); call->setMetadata(msgSendMDKind, node); if (!isPointerSizedReturn) { messageBB = CGF.Builder.GetInsertBlock(); CGF.Builder.CreateBr(continueBB); CGF.EmitBlock(continueBB); if (msgRet.isScalar()) { llvm::Value *v = msgRet.getScalarVal(); llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2); phi->addIncoming(v, messageBB); phi->addIncoming(llvm::Constant::getNullValue(v->getType()), startBB); msgRet = RValue::get(phi); } else if (msgRet.isAggregate()) { llvm::Value *v = msgRet.getAggregateAddr(); llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2); llvm::PointerType *RetTy = cast<llvm::PointerType>(v->getType()); llvm::AllocaInst *NullVal = CGF.CreateTempAlloca(RetTy->getElementType(), "null"); CGF.InitTempAlloca(NullVal, llvm::Constant::getNullValue(RetTy->getElementType())); phi->addIncoming(v, messageBB); phi->addIncoming(NullVal, startBB); msgRet = RValue::getAggregate(phi); } else /* isComplex() */ { std::pair<llvm::Value*,llvm::Value*> v = msgRet.getComplexVal(); llvm::PHINode *phi = Builder.CreatePHI(v.first->getType(), 2); phi->addIncoming(v.first, messageBB); phi->addIncoming(llvm::Constant::getNullValue(v.first->getType()), startBB); llvm::PHINode *phi2 = Builder.CreatePHI(v.second->getType(), 2); phi2->addIncoming(v.second, messageBB); phi2->addIncoming(llvm::Constant::getNullValue(v.second->getType()), startBB); msgRet = RValue::getComplex(phi, phi2); } } return msgRet; } /// Generates a MethodList. Used in construction of a objc_class and /// objc_category structures. llvm::Constant *CGObjCGNU:: GenerateMethodList(const StringRef &ClassName, const StringRef &CategoryName, ArrayRef<Selector> MethodSels, ArrayRef<llvm::Constant *> MethodTypes, bool isClassMethodList) { if (MethodSels.empty()) return NULLPtr; // Get the method structure type. llvm::StructType *ObjCMethodTy = llvm::StructType::get( PtrToInt8Ty, // Really a selector, but the runtime creates it us. PtrToInt8Ty, // Method types IMPTy, //Method pointer NULL); std::vector<llvm::Constant*> Methods; std::vector<llvm::Constant*> Elements; for (unsigned int i = 0, e = MethodTypes.size(); i < e; ++i) { Elements.clear(); llvm::Constant *Method = TheModule.getFunction(SymbolNameForMethod(ClassName, CategoryName, MethodSels[i], isClassMethodList)); assert(Method && "Can't generate metadata for method that doesn't exist"); llvm::Constant *C = MakeConstantString(MethodSels[i].getAsString()); Elements.push_back(C); Elements.push_back(MethodTypes[i]); Method = llvm::ConstantExpr::getBitCast(Method, IMPTy); Elements.push_back(Method); Methods.push_back(llvm::ConstantStruct::get(ObjCMethodTy, Elements)); } // Array of method structures llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodTy, Methods.size()); llvm::Constant *MethodArray = llvm::ConstantArray::get(ObjCMethodArrayTy, Methods); // Structure containing list pointer, array and array count llvm::StructType *ObjCMethodListTy = llvm::StructType::create(VMContext); llvm::Type *NextPtrTy = llvm::PointerType::getUnqual(ObjCMethodListTy); ObjCMethodListTy->setBody( NextPtrTy, IntTy, ObjCMethodArrayTy, NULL); Methods.clear(); Methods.push_back(llvm::ConstantPointerNull::get( llvm::PointerType::getUnqual(ObjCMethodListTy))); Methods.push_back(llvm::ConstantInt::get(Int32Ty, MethodTypes.size())); Methods.push_back(MethodArray); // Create an instance of the structure return MakeGlobal(ObjCMethodListTy, Methods, ".objc_method_list"); } /// Generates an IvarList. Used in construction of a objc_class. llvm::Constant *CGObjCGNU:: GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames, ArrayRef<llvm::Constant *> IvarTypes, ArrayRef<llvm::Constant *> IvarOffsets) { if (IvarNames.size() == 0) return NULLPtr; // Get the method structure type. llvm::StructType *ObjCIvarTy = llvm::StructType::get( PtrToInt8Ty, PtrToInt8Ty, IntTy, NULL); std::vector<llvm::Constant*> Ivars; std::vector<llvm::Constant*> Elements; for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) { Elements.clear(); Elements.push_back(IvarNames[i]); Elements.push_back(IvarTypes[i]); Elements.push_back(IvarOffsets[i]); Ivars.push_back(llvm::ConstantStruct::get(ObjCIvarTy, Elements)); } // Array of method structures llvm::ArrayType *ObjCIvarArrayTy = llvm::ArrayType::get(ObjCIvarTy, IvarNames.size()); Elements.clear(); Elements.push_back(llvm::ConstantInt::get(IntTy, (int)IvarNames.size())); Elements.push_back(llvm::ConstantArray::get(ObjCIvarArrayTy, Ivars)); // Structure containing array and array count llvm::StructType *ObjCIvarListTy = llvm::StructType::get(IntTy, ObjCIvarArrayTy, NULL); // Create an instance of the structure return MakeGlobal(ObjCIvarListTy, Elements, ".objc_ivar_list"); } /// Generate a class structure llvm::Constant *CGObjCGNU::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) { // Set up the class structure // Note: Several of these are char*s when they should be ids. This is // because the runtime performs this translation on load. // // Fields marked New ABI are part of the GNUstep runtime. We emit them // anyway; the classes will still work with the GNU runtime, they will just // be ignored. llvm::StructType *ClassTy = llvm::StructType::get( PtrToInt8Ty, // isa PtrToInt8Ty, // super_class PtrToInt8Ty, // name LongTy, // version LongTy, // info LongTy, // instance_size IVars->getType(), // ivars Methods->getType(), // methods // These are all filled in by the runtime, so we pretend PtrTy, // dtable PtrTy, // subclass_list PtrTy, // sibling_class PtrTy, // protocols PtrTy, // gc_object_type // New ABI: LongTy, // abi_version IvarOffsets->getType(), // ivar_offsets Properties->getType(), // properties IntPtrTy, // strong_pointers IntPtrTy, // weak_pointers NULL); llvm::Constant *Zero = llvm::ConstantInt::get(LongTy, 0); // Fill in the structure std::vector<llvm::Constant*> Elements; Elements.push_back(llvm::ConstantExpr::getBitCast(MetaClass, PtrToInt8Ty)); Elements.push_back(SuperClass); Elements.push_back(MakeConstantString(Name, ".class_name")); Elements.push_back(Zero); Elements.push_back(llvm::ConstantInt::get(LongTy, info)); if (isMeta) { llvm::TargetData td(&TheModule); Elements.push_back( llvm::ConstantInt::get(LongTy, td.getTypeSizeInBits(ClassTy) / CGM.getContext().getCharWidth())); } else Elements.push_back(InstanceSize); Elements.push_back(IVars); Elements.push_back(Methods); Elements.push_back(NULLPtr); Elements.push_back(NULLPtr); Elements.push_back(NULLPtr); Elements.push_back(llvm::ConstantExpr::getBitCast(Protocols, PtrTy)); Elements.push_back(NULLPtr); Elements.push_back(llvm::ConstantInt::get(LongTy, 1)); Elements.push_back(IvarOffsets); Elements.push_back(Properties); Elements.push_back(StrongIvarBitmap); Elements.push_back(WeakIvarBitmap); // Create an instance of the structure // This is now an externally visible symbol, so that we can speed up class // messages in the next ABI. We may already have some weak references to // this, so check and fix them properly. std::string ClassSym((isMeta ? "_OBJC_METACLASS_": "_OBJC_CLASS_") + std::string(Name)); llvm::GlobalVariable *ClassRef = TheModule.getNamedGlobal(ClassSym); llvm::Constant *Class = MakeGlobal(ClassTy, Elements, ClassSym, llvm::GlobalValue::ExternalLinkage); if (ClassRef) { ClassRef->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(Class, ClassRef->getType())); ClassRef->removeFromParent(); Class->setName(ClassSym); } return Class; } llvm::Constant *CGObjCGNU:: GenerateProtocolMethodList(ArrayRef<llvm::Constant *> MethodNames, ArrayRef<llvm::Constant *> MethodTypes) { // Get the method structure type. llvm::StructType *ObjCMethodDescTy = llvm::StructType::get( PtrToInt8Ty, // Really a selector, but the runtime does the casting for us. PtrToInt8Ty, NULL); std::vector<llvm::Constant*> Methods; std::vector<llvm::Constant*> Elements; for (unsigned int i = 0, e = MethodTypes.size() ; i < e ; i++) { Elements.clear(); Elements.push_back(MethodNames[i]); Elements.push_back(MethodTypes[i]); Methods.push_back(llvm::ConstantStruct::get(ObjCMethodDescTy, Elements)); } llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodDescTy, MethodNames.size()); llvm::Constant *Array = llvm::ConstantArray::get(ObjCMethodArrayTy, Methods); llvm::StructType *ObjCMethodDescListTy = llvm::StructType::get( IntTy, ObjCMethodArrayTy, NULL); Methods.clear(); Methods.push_back(llvm::ConstantInt::get(IntTy, MethodNames.size())); Methods.push_back(Array); return MakeGlobal(ObjCMethodDescListTy, Methods, ".objc_method_list"); } // Create the protocol list structure used in classes, categories and so on llvm::Constant *CGObjCGNU::GenerateProtocolList(ArrayRef<std::string>Protocols){ llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrToInt8Ty, Protocols.size()); llvm::StructType *ProtocolListTy = llvm::StructType::get( PtrTy, //Should be a recurisve pointer, but it's always NULL here. SizeTy, ProtocolArrayTy, NULL); std::vector<llvm::Constant*> Elements; for (const std::string *iter = Protocols.begin(), *endIter = Protocols.end(); iter != endIter ; iter++) { llvm::Constant *protocol = 0; llvm::StringMap<llvm::Constant*>::iterator value = ExistingProtocols.find(*iter); if (value == ExistingProtocols.end()) { protocol = GenerateEmptyProtocol(*iter); } else { protocol = value->getValue(); } llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(protocol, PtrToInt8Ty); Elements.push_back(Ptr); } llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy, Elements); Elements.clear(); Elements.push_back(NULLPtr); Elements.push_back(llvm::ConstantInt::get(LongTy, Protocols.size())); Elements.push_back(ProtocolArray); return MakeGlobal(ProtocolListTy, Elements, ".objc_protocol_list"); } llvm::Value *CGObjCGNU::GenerateProtocolRef(CGBuilderTy &Builder, const ObjCProtocolDecl *PD) { llvm::Value *protocol = ExistingProtocols[PD->getNameAsString()]; llvm::Type *T = CGM.getTypes().ConvertType(CGM.getContext().getObjCProtoType()); return Builder.CreateBitCast(protocol, llvm::PointerType::getUnqual(T)); } llvm::Constant *CGObjCGNU::GenerateEmptyProtocol( const std::string &ProtocolName) { SmallVector<std::string, 0> EmptyStringVector; SmallVector<llvm::Constant*, 0> EmptyConstantVector; llvm::Constant *ProtocolList = GenerateProtocolList(EmptyStringVector); llvm::Constant *MethodList = GenerateProtocolMethodList(EmptyConstantVector, EmptyConstantVector); // Protocols are objects containing lists of the methods implemented and // protocols adopted. llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy, PtrToInt8Ty, ProtocolList->getType(), MethodList->getType(), MethodList->getType(), MethodList->getType(), MethodList->getType(), NULL); std::vector<llvm::Constant*> Elements; // The isa pointer must be set to a magic number so the runtime knows it's // the correct layout. Elements.push_back(llvm::ConstantExpr::getIntToPtr( llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy)); Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name")); Elements.push_back(ProtocolList); Elements.push_back(MethodList); Elements.push_back(MethodList); Elements.push_back(MethodList); Elements.push_back(MethodList); return MakeGlobal(ProtocolTy, Elements, ".objc_protocol"); } void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) { ASTContext &Context = CGM.getContext(); std::string ProtocolName = PD->getNameAsString(); // Use the protocol definition, if there is one. if (const ObjCProtocolDecl *Def = PD->getDefinition()) PD = Def; SmallVector<std::string, 16> Protocols; for (ObjCProtocolDecl::protocol_iterator PI = PD->protocol_begin(), E = PD->protocol_end(); PI != E; ++PI) Protocols.push_back((*PI)->getNameAsString()); SmallVector<llvm::Constant*, 16> InstanceMethodNames; SmallVector<llvm::Constant*, 16> InstanceMethodTypes; SmallVector<llvm::Constant*, 16> OptionalInstanceMethodNames; SmallVector<llvm::Constant*, 16> OptionalInstanceMethodTypes; for (ObjCProtocolDecl::instmeth_iterator iter = PD->instmeth_begin(), E = PD->instmeth_end(); iter != E; iter++) { std::string TypeStr; Context.getObjCEncodingForMethodDecl(*iter, TypeStr); if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) { InstanceMethodNames.push_back( MakeConstantString((*iter)->getSelector().getAsString())); InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); } else { OptionalInstanceMethodNames.push_back( MakeConstantString((*iter)->getSelector().getAsString())); OptionalInstanceMethodTypes.push_back(MakeConstantString(TypeStr)); } } // Collect information about class methods: SmallVector<llvm::Constant*, 16> ClassMethodNames; SmallVector<llvm::Constant*, 16> ClassMethodTypes; SmallVector<llvm::Constant*, 16> OptionalClassMethodNames; SmallVector<llvm::Constant*, 16> OptionalClassMethodTypes; for (ObjCProtocolDecl::classmeth_iterator iter = PD->classmeth_begin(), endIter = PD->classmeth_end(); iter != endIter ; iter++) { std::string TypeStr; Context.getObjCEncodingForMethodDecl((*iter),TypeStr); if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) { ClassMethodNames.push_back( MakeConstantString((*iter)->getSelector().getAsString())); ClassMethodTypes.push_back(MakeConstantString(TypeStr)); } else { OptionalClassMethodNames.push_back( MakeConstantString((*iter)->getSelector().getAsString())); OptionalClassMethodTypes.push_back(MakeConstantString(TypeStr)); } } llvm::Constant *ProtocolList = GenerateProtocolList(Protocols); llvm::Constant *InstanceMethodList = GenerateProtocolMethodList(InstanceMethodNames, InstanceMethodTypes); llvm::Constant *ClassMethodList = GenerateProtocolMethodList(ClassMethodNames, ClassMethodTypes); llvm::Constant *OptionalInstanceMethodList = GenerateProtocolMethodList(OptionalInstanceMethodNames, OptionalInstanceMethodTypes); llvm::Constant *OptionalClassMethodList = GenerateProtocolMethodList(OptionalClassMethodNames, OptionalClassMethodTypes); // Property metadata: name, attributes, isSynthesized, setter name, setter // types, getter name, getter types. // The isSynthesized value is always set to 0 in a protocol. It exists to // simplify the runtime library by allowing it to use the same data // structures for protocol metadata everywhere. llvm::StructType *PropertyMetadataTy = llvm::StructType::get( PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, NULL); std::vector<llvm::Constant*> Properties; std::vector<llvm::Constant*> OptionalProperties; // Add all of the property methods need adding to the method list and to the // property metadata list. for (ObjCContainerDecl::prop_iterator iter = PD->prop_begin(), endIter = PD->prop_end(); iter != endIter ; iter++) { std::vector<llvm::Constant*> Fields; ObjCPropertyDecl *property = (*iter); Fields.push_back(MakeConstantString(property->getNameAsString())); Fields.push_back(llvm::ConstantInt::get(Int8Ty, property->getPropertyAttributes())); Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0)); if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) { std::string TypeStr; Context.getObjCEncodingForMethodDecl(getter,TypeStr); llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); InstanceMethodTypes.push_back(TypeEncoding); Fields.push_back(MakeConstantString(getter->getSelector().getAsString())); Fields.push_back(TypeEncoding); } else { Fields.push_back(NULLPtr); Fields.push_back(NULLPtr); } if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) { std::string TypeStr; Context.getObjCEncodingForMethodDecl(setter,TypeStr); llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); InstanceMethodTypes.push_back(TypeEncoding); Fields.push_back(MakeConstantString(setter->getSelector().getAsString())); Fields.push_back(TypeEncoding); } else { Fields.push_back(NULLPtr); Fields.push_back(NULLPtr); } if (property->getPropertyImplementation() == ObjCPropertyDecl::Optional) { OptionalProperties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); } else { Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); } } llvm::Constant *PropertyArray = llvm::ConstantArray::get( llvm::ArrayType::get(PropertyMetadataTy, Properties.size()), Properties); llvm::Constant* PropertyListInitFields[] = {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray}; llvm::Constant *PropertyListInit = llvm::ConstantStruct::getAnon(PropertyListInitFields); llvm::Constant *PropertyList = new llvm::GlobalVariable(TheModule, PropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage, PropertyListInit, ".objc_property_list"); llvm::Constant *OptionalPropertyArray = llvm::ConstantArray::get(llvm::ArrayType::get(PropertyMetadataTy, OptionalProperties.size()) , OptionalProperties); llvm::Constant* OptionalPropertyListInitFields[] = { llvm::ConstantInt::get(IntTy, OptionalProperties.size()), NULLPtr, OptionalPropertyArray }; llvm::Constant *OptionalPropertyListInit = llvm::ConstantStruct::getAnon(OptionalPropertyListInitFields); llvm::Constant *OptionalPropertyList = new llvm::GlobalVariable(TheModule, OptionalPropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage, OptionalPropertyListInit, ".objc_property_list"); // Protocols are objects containing lists of the methods implemented and // protocols adopted. llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy, PtrToInt8Ty, ProtocolList->getType(), InstanceMethodList->getType(), ClassMethodList->getType(), OptionalInstanceMethodList->getType(), OptionalClassMethodList->getType(), PropertyList->getType(), OptionalPropertyList->getType(), NULL); std::vector<llvm::Constant*> Elements; // The isa pointer must be set to a magic number so the runtime knows it's // the correct layout. Elements.push_back(llvm::ConstantExpr::getIntToPtr( llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy)); Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name")); Elements.push_back(ProtocolList); Elements.push_back(InstanceMethodList); Elements.push_back(ClassMethodList); Elements.push_back(OptionalInstanceMethodList); Elements.push_back(OptionalClassMethodList); Elements.push_back(PropertyList); Elements.push_back(OptionalPropertyList); ExistingProtocols[ProtocolName] = llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolTy, Elements, ".objc_protocol"), IdTy); } void CGObjCGNU::GenerateProtocolHolderCategory(void) { // Collect information about instance methods SmallVector<Selector, 1> MethodSels; SmallVector<llvm::Constant*, 1> MethodTypes; std::vector<llvm::Constant*> Elements; const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack"; const std::string CategoryName = "AnotherHack"; Elements.push_back(MakeConstantString(CategoryName)); Elements.push_back(MakeConstantString(ClassName)); // Instance method list Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( ClassName, CategoryName, MethodSels, MethodTypes, false), PtrTy)); // Class method list Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( ClassName, CategoryName, MethodSels, MethodTypes, true), PtrTy)); // Protocol list llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrTy, ExistingProtocols.size()); llvm::StructType *ProtocolListTy = llvm::StructType::get( PtrTy, //Should be a recurisve pointer, but it's always NULL here. SizeTy, ProtocolArrayTy, NULL); std::vector<llvm::Constant*> ProtocolElements; for (llvm::StringMapIterator<llvm::Constant*> iter = ExistingProtocols.begin(), endIter = ExistingProtocols.end(); iter != endIter ; iter++) { llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(iter->getValue(), PtrTy); ProtocolElements.push_back(Ptr); } llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy, ProtocolElements); ProtocolElements.clear(); ProtocolElements.push_back(NULLPtr); ProtocolElements.push_back(llvm::ConstantInt::get(LongTy, ExistingProtocols.size())); ProtocolElements.push_back(ProtocolArray); Elements.push_back(llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolListTy, ProtocolElements, ".objc_protocol_list"), PtrTy)); Categories.push_back(llvm::ConstantExpr::getBitCast( MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy)); } /// 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 *CGObjCGNU::MakeBitField(ArrayRef<bool> bits) { int bitCount = bits.size(); int ptrBits = (TheModule.getPointerSize() == llvm::Module::Pointer32) ? 32 : 64; if (bitCount < ptrBits) { uint64_t val = 1; for (int i=0 ; i<bitCount ; ++i) { if (bits[i]) val |= 1ULL<<(i+1); } return llvm::ConstantInt::get(IntPtrTy, val); } llvm::SmallVector<llvm::Constant*, 8> values; int v=0; while (v < bitCount) { int32_t word = 0; for (int i=0 ; (i<32) && (v<bitCount) ; ++i) { if (bits[v]) word |= 1<<i; v++; } values.push_back(llvm::ConstantInt::get(Int32Ty, word)); } llvm::ArrayType *arrayTy = llvm::ArrayType::get(Int32Ty, values.size()); llvm::Constant *array = llvm::ConstantArray::get(arrayTy, values); llvm::Constant *fields[2] = { llvm::ConstantInt::get(Int32Ty, values.size()), array }; llvm::Constant *GS = MakeGlobal(llvm::StructType::get(Int32Ty, arrayTy, NULL), fields); llvm::Constant *ptr = llvm::ConstantExpr::getPtrToInt(GS, IntPtrTy); return ptr; } void CGObjCGNU::GenerateCategory(const ObjCCategoryImplDecl *OCD) { std::string ClassName = OCD->getClassInterface()->getNameAsString(); std::string CategoryName = OCD->getNameAsString(); // Collect information about instance methods SmallVector<Selector, 16> InstanceMethodSels; SmallVector<llvm::Constant*, 16> InstanceMethodTypes; for (ObjCCategoryImplDecl::instmeth_iterator iter = OCD->instmeth_begin(), endIter = OCD->instmeth_end(); iter != endIter ; iter++) { InstanceMethodSels.push_back((*iter)->getSelector()); std::string TypeStr; CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr); InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); } // Collect information about class methods SmallVector<Selector, 16> ClassMethodSels; SmallVector<llvm::Constant*, 16> ClassMethodTypes; for (ObjCCategoryImplDecl::classmeth_iterator iter = OCD->classmeth_begin(), endIter = OCD->classmeth_end(); iter != endIter ; iter++) { ClassMethodSels.push_back((*iter)->getSelector()); std::string TypeStr; CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr); ClassMethodTypes.push_back(MakeConstantString(TypeStr)); } // Collect the names of referenced protocols SmallVector<std::string, 16> Protocols; const ObjCCategoryDecl *CatDecl = OCD->getCategoryDecl(); const ObjCList<ObjCProtocolDecl> &Protos = CatDecl->getReferencedProtocols(); for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(), E = Protos.end(); I != E; ++I) Protocols.push_back((*I)->getNameAsString()); std::vector<llvm::Constant*> Elements; Elements.push_back(MakeConstantString(CategoryName)); Elements.push_back(MakeConstantString(ClassName)); // Instance method list Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( ClassName, CategoryName, InstanceMethodSels, InstanceMethodTypes, false), PtrTy)); // Class method list Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( ClassName, CategoryName, ClassMethodSels, ClassMethodTypes, true), PtrTy)); // Protocol list Elements.push_back(llvm::ConstantExpr::getBitCast( GenerateProtocolList(Protocols), PtrTy)); Categories.push_back(llvm::ConstantExpr::getBitCast( MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy)); } llvm::Constant *CGObjCGNU::GeneratePropertyList(const ObjCImplementationDecl *OID, SmallVectorImpl<Selector> &InstanceMethodSels, SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes) { ASTContext &Context = CGM.getContext(); // // Property metadata: name, attributes, isSynthesized, setter name, setter // types, getter name, getter types. llvm::StructType *PropertyMetadataTy = llvm::StructType::get( PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, NULL); std::vector<llvm::Constant*> Properties; // Add all of the property methods need adding to the method list and to the // property metadata list. for (ObjCImplDecl::propimpl_iterator iter = OID->propimpl_begin(), endIter = OID->propimpl_end(); iter != endIter ; iter++) { std::vector<llvm::Constant*> Fields; ObjCPropertyDecl *property = (*iter)->getPropertyDecl(); ObjCPropertyImplDecl *propertyImpl = *iter; bool isSynthesized = (propertyImpl->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize); Fields.push_back(MakeConstantString(property->getNameAsString())); Fields.push_back(llvm::ConstantInt::get(Int8Ty, property->getPropertyAttributes())); Fields.push_back(llvm::ConstantInt::get(Int8Ty, isSynthesized)); if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) { std::string TypeStr; Context.getObjCEncodingForMethodDecl(getter,TypeStr); llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); if (isSynthesized) { InstanceMethodTypes.push_back(TypeEncoding); InstanceMethodSels.push_back(getter->getSelector()); } Fields.push_back(MakeConstantString(getter->getSelector().getAsString())); Fields.push_back(TypeEncoding); } else { Fields.push_back(NULLPtr); Fields.push_back(NULLPtr); } if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) { std::string TypeStr; Context.getObjCEncodingForMethodDecl(setter,TypeStr); llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); if (isSynthesized) { InstanceMethodTypes.push_back(TypeEncoding); InstanceMethodSels.push_back(setter->getSelector()); } Fields.push_back(MakeConstantString(setter->getSelector().getAsString())); Fields.push_back(TypeEncoding); } else { Fields.push_back(NULLPtr); Fields.push_back(NULLPtr); } Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); } llvm::ArrayType *PropertyArrayTy = llvm::ArrayType::get(PropertyMetadataTy, Properties.size()); llvm::Constant *PropertyArray = llvm::ConstantArray::get(PropertyArrayTy, Properties); llvm::Constant* PropertyListInitFields[] = {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray}; llvm::Constant *PropertyListInit = llvm::ConstantStruct::getAnon(PropertyListInitFields); return new llvm::GlobalVariable(TheModule, PropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage, PropertyListInit, ".objc_property_list"); } void CGObjCGNU::RegisterAlias(const ObjCCompatibleAliasDecl *OAD) { // Get the class declaration for which the alias is specified. ObjCInterfaceDecl *ClassDecl = const_cast<ObjCInterfaceDecl *>(OAD->getClassInterface()); std::string ClassName = ClassDecl->getNameAsString(); std::string AliasName = OAD->getNameAsString(); ClassAliases.push_back(ClassAliasPair(ClassName,AliasName)); } void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) { ASTContext &Context = CGM.getContext(); // Get the superclass name. const ObjCInterfaceDecl * SuperClassDecl = OID->getClassInterface()->getSuperClass(); std::string SuperClassName; if (SuperClassDecl) { SuperClassName = SuperClassDecl->getNameAsString(); EmitClassRef(SuperClassName); } // Get the class name ObjCInterfaceDecl *ClassDecl = const_cast<ObjCInterfaceDecl *>(OID->getClassInterface()); std::string ClassName = ClassDecl->getNameAsString(); // Emit the symbol that is used to generate linker errors if this class is // referenced in other modules but not declared. std::string classSymbolName = "__objc_class_name_" + ClassName; if (llvm::GlobalVariable *symbol = TheModule.getGlobalVariable(classSymbolName)) { symbol->setInitializer(llvm::ConstantInt::get(LongTy, 0)); } else { new llvm::GlobalVariable(TheModule, LongTy, false, llvm::GlobalValue::ExternalLinkage, llvm::ConstantInt::get(LongTy, 0), classSymbolName); } // Get the size of instances. int instanceSize = Context.getASTObjCImplementationLayout(OID).getSize().getQuantity(); // Collect information about instance variables. SmallVector<llvm::Constant*, 16> IvarNames; SmallVector<llvm::Constant*, 16> IvarTypes; SmallVector<llvm::Constant*, 16> IvarOffsets; std::vector<llvm::Constant*> IvarOffsetValues; SmallVector<bool, 16> WeakIvars; SmallVector<bool, 16> StrongIvars; int superInstanceSize = !SuperClassDecl ? 0 : Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity(); // For non-fragile ivars, set the instance size to 0 - {the size of just this // class}. The runtime will then set this to the correct value on load. if (CGM.getContext().getLangOpts().ObjCNonFragileABI) { instanceSize = 0 - (instanceSize - superInstanceSize); } for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD; IVD = IVD->getNextIvar()) { // Store the name IvarNames.push_back(MakeConstantString(IVD->getNameAsString())); // Get the type encoding for this ivar std::string TypeStr; Context.getObjCEncodingForType(IVD->getType(), TypeStr); IvarTypes.push_back(MakeConstantString(TypeStr)); // Get the offset uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD); uint64_t Offset = BaseOffset; if (CGM.getContext().getLangOpts().ObjCNonFragileABI) { Offset = BaseOffset - superInstanceSize; } llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset); // Create the direct offset value std::string OffsetName = "__objc_ivar_offset_value_" + ClassName +"." + IVD->getNameAsString(); llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName); if (OffsetVar) { OffsetVar->setInitializer(OffsetValue); // If this is the real definition, change its linkage type so that // different modules will use this one, rather than their private // copy. OffsetVar->setLinkage(llvm::GlobalValue::ExternalLinkage); } else OffsetVar = new llvm::GlobalVariable(TheModule, IntTy, false, llvm::GlobalValue::ExternalLinkage, OffsetValue, "__objc_ivar_offset_value_" + ClassName +"." + IVD->getNameAsString()); IvarOffsets.push_back(OffsetValue); IvarOffsetValues.push_back(OffsetVar); Qualifiers::ObjCLifetime lt = IVD->getType().getQualifiers().getObjCLifetime(); switch (lt) { case Qualifiers::OCL_Strong: StrongIvars.push_back(true); WeakIvars.push_back(false); break; case Qualifiers::OCL_Weak: StrongIvars.push_back(false); WeakIvars.push_back(true); break; default: StrongIvars.push_back(false); WeakIvars.push_back(false); } } llvm::Constant *StrongIvarBitmap = MakeBitField(StrongIvars); llvm::Constant *WeakIvarBitmap = MakeBitField(WeakIvars); llvm::GlobalVariable *IvarOffsetArray = MakeGlobalArray(PtrToIntTy, IvarOffsetValues, ".ivar.offsets"); // Collect information about instance methods SmallVector<Selector, 16> InstanceMethodSels; SmallVector<llvm::Constant*, 16> InstanceMethodTypes; for (ObjCImplementationDecl::instmeth_iterator iter = OID->instmeth_begin(), endIter = OID->instmeth_end(); iter != endIter ; iter++) { InstanceMethodSels.push_back((*iter)->getSelector()); std::string TypeStr; Context.getObjCEncodingForMethodDecl((*iter),TypeStr); InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); } llvm::Constant *Properties = GeneratePropertyList(OID, InstanceMethodSels, InstanceMethodTypes); // Collect information about class methods SmallVector<Selector, 16> ClassMethodSels; SmallVector<llvm::Constant*, 16> ClassMethodTypes; for (ObjCImplementationDecl::classmeth_iterator iter = OID->classmeth_begin(), endIter = OID->classmeth_end(); iter != endIter ; iter++) { ClassMethodSels.push_back((*iter)->getSelector()); std::string TypeStr; Context.getObjCEncodingForMethodDecl((*iter),TypeStr); ClassMethodTypes.push_back(MakeConstantString(TypeStr)); } // Collect the names of referenced protocols SmallVector<std::string, 16> Protocols; for (ObjCInterfaceDecl::protocol_iterator I = ClassDecl->protocol_begin(), E = ClassDecl->protocol_end(); I != E; ++I) Protocols.push_back((*I)->getNameAsString()); // Get the superclass pointer. llvm::Constant *SuperClass; if (!SuperClassName.empty()) { SuperClass = MakeConstantString(SuperClassName, ".super_class_name"); } else { SuperClass = llvm::ConstantPointerNull::get(PtrToInt8Ty); } // Empty vector used to construct empty method lists SmallVector<llvm::Constant*, 1> empty; // Generate the method and instance variable lists llvm::Constant *MethodList = GenerateMethodList(ClassName, "", InstanceMethodSels, InstanceMethodTypes, false); llvm::Constant *ClassMethodList = GenerateMethodList(ClassName, "", ClassMethodSels, ClassMethodTypes, true); llvm::Constant *IvarList = GenerateIvarList(IvarNames, IvarTypes, IvarOffsets); // Irrespective of whether we are compiling for a fragile or non-fragile ABI, // we emit a symbol containing the offset for each ivar in the class. This // allows code compiled for the non-Fragile ABI to inherit from code compiled // for the legacy ABI, without causing problems. The converse is also // possible, but causes all ivar accesses to be fragile. // Offset pointer for getting at the correct field in the ivar list when // setting up the alias. These are: The base address for the global, the // ivar array (second field), the ivar in this list (set for each ivar), and // the offset (third field in ivar structure) llvm::Type *IndexTy = Int32Ty; llvm::Constant *offsetPointerIndexes[] = {Zeros[0], llvm::ConstantInt::get(IndexTy, 1), 0, llvm::ConstantInt::get(IndexTy, 2) }; unsigned ivarIndex = 0; for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD; IVD = IVD->getNextIvar()) { const std::string Name = "__objc_ivar_offset_" + ClassName + '.' + IVD->getNameAsString(); offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, ivarIndex); // Get the correct ivar field llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr( IvarList, offsetPointerIndexes); // Get the existing variable, if one exists. llvm::GlobalVariable *offset = TheModule.getNamedGlobal(Name); if (offset) { offset->setInitializer(offsetValue); // If this is the real definition, change its linkage type so that // different modules will use this one, rather than their private // copy. offset->setLinkage(llvm::GlobalValue::ExternalLinkage); } else { // Add a new alias if there isn't one already. offset = new llvm::GlobalVariable(TheModule, offsetValue->getType(), false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name); (void) offset; // Silence dead store warning. } ++ivarIndex; } llvm::Constant *ZeroPtr = llvm::ConstantInt::get(IntPtrTy, 0); //Generate metaclass for class methods llvm::Constant *MetaClassStruct = GenerateClassStructure(NULLPtr, NULLPtr, 0x12L, ClassName.c_str(), 0, Zeros[0], GenerateIvarList( empty, empty, empty), ClassMethodList, NULLPtr, NULLPtr, NULLPtr, ZeroPtr, ZeroPtr, true); // Generate the class structure llvm::Constant *ClassStruct = GenerateClassStructure(MetaClassStruct, SuperClass, 0x11L, ClassName.c_str(), 0, llvm::ConstantInt::get(LongTy, instanceSize), IvarList, MethodList, GenerateProtocolList(Protocols), IvarOffsetArray, Properties, StrongIvarBitmap, WeakIvarBitmap); // Resolve the class aliases, if they exist. if (ClassPtrAlias) { ClassPtrAlias->replaceAllUsesWith( llvm::ConstantExpr::getBitCast(ClassStruct, IdTy)); ClassPtrAlias->eraseFromParent(); ClassPtrAlias = 0; } if (MetaClassPtrAlias) { MetaClassPtrAlias->replaceAllUsesWith( llvm::ConstantExpr::getBitCast(MetaClassStruct, IdTy)); MetaClassPtrAlias->eraseFromParent(); MetaClassPtrAlias = 0; } // Add class structure to list to be added to the symtab later ClassStruct = llvm::ConstantExpr::getBitCast(ClassStruct, PtrToInt8Ty); Classes.push_back(ClassStruct); } llvm::Function *CGObjCGNU::ModuleInitFunction() { // Only emit an ObjC load function if no Objective-C stuff has been called if (Classes.empty() && Categories.empty() && ConstantStrings.empty() && ExistingProtocols.empty() && SelectorTable.empty()) return NULL; // Add all referenced protocols to a category. GenerateProtocolHolderCategory(); llvm::StructType *SelStructTy = dyn_cast<llvm::StructType>( SelectorTy->getElementType()); llvm::Type *SelStructPtrTy = SelectorTy; if (SelStructTy == 0) { SelStructTy = llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, NULL); SelStructPtrTy = llvm::PointerType::getUnqual(SelStructTy); } std::vector<llvm::Constant*> Elements; llvm::Constant *Statics = NULLPtr; // Generate statics list: if (ConstantStrings.size()) { llvm::ArrayType *StaticsArrayTy = llvm::ArrayType::get(PtrToInt8Ty, ConstantStrings.size() + 1); ConstantStrings.push_back(NULLPtr); StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass; if (StringClass.empty()) StringClass = "NXConstantString"; Elements.push_back(MakeConstantString(StringClass, ".objc_static_class_name")); Elements.push_back(llvm::ConstantArray::get(StaticsArrayTy, ConstantStrings)); llvm::StructType *StaticsListTy = llvm::StructType::get(PtrToInt8Ty, StaticsArrayTy, NULL); llvm::Type *StaticsListPtrTy = llvm::PointerType::getUnqual(StaticsListTy); Statics = MakeGlobal(StaticsListTy, Elements, ".objc_statics"); llvm::ArrayType *StaticsListArrayTy = llvm::ArrayType::get(StaticsListPtrTy, 2); Elements.clear(); Elements.push_back(Statics); Elements.push_back(llvm::Constant::getNullValue(StaticsListPtrTy)); Statics = MakeGlobal(StaticsListArrayTy, Elements, ".objc_statics_ptr"); Statics = llvm::ConstantExpr::getBitCast(Statics, PtrTy); } // Array of classes, categories, and constant objects llvm::ArrayType *ClassListTy = llvm::ArrayType::get(PtrToInt8Ty, Classes.size() + Categories.size() + 2); llvm::StructType *SymTabTy = llvm::StructType::get(LongTy, SelStructPtrTy, llvm::Type::getInt16Ty(VMContext), llvm::Type::getInt16Ty(VMContext), ClassListTy, NULL); Elements.clear(); // Pointer to an array of selectors used in this module. std::vector<llvm::Constant*> Selectors; std::vector<llvm::GlobalAlias*> SelectorAliases; for (SelectorMap::iterator iter = SelectorTable.begin(), iterEnd = SelectorTable.end(); iter != iterEnd ; ++iter) { std::string SelNameStr = iter->first.getAsString(); llvm::Constant *SelName = ExportUniqueString(SelNameStr, ".objc_sel_name"); SmallVectorImpl<TypedSelector> &Types = iter->second; for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(), e = Types.end() ; i!=e ; i++) { llvm::Constant *SelectorTypeEncoding = NULLPtr; if (!i->first.empty()) SelectorTypeEncoding = MakeConstantString(i->first, ".objc_sel_types"); Elements.push_back(SelName); Elements.push_back(SelectorTypeEncoding); Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements)); Elements.clear(); // Store the selector alias for later replacement SelectorAliases.push_back(i->second); } } unsigned SelectorCount = Selectors.size(); // NULL-terminate the selector list. This should not actually be required, // because the selector list has a length field. Unfortunately, the GCC // runtime decides to ignore the length field and expects a NULL terminator, // and GCC cooperates with this by always setting the length to 0. Elements.push_back(NULLPtr); Elements.push_back(NULLPtr); Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements)); Elements.clear(); // Number of static selectors Elements.push_back(llvm::ConstantInt::get(LongTy, SelectorCount)); llvm::Constant *SelectorList = MakeGlobalArray(SelStructTy, Selectors, ".objc_selector_list"); Elements.push_back(llvm::ConstantExpr::getBitCast(SelectorList, SelStructPtrTy)); // Now that all of the static selectors exist, create pointers to them. for (unsigned int i=0 ; i<SelectorCount ; i++) { llvm::Constant *Idxs[] = {Zeros[0], llvm::ConstantInt::get(Int32Ty, i), Zeros[0]}; // FIXME: We're generating redundant loads and stores here! llvm::Constant *SelPtr = llvm::ConstantExpr::getGetElementPtr(SelectorList, makeArrayRef(Idxs, 2)); // If selectors are defined as an opaque type, cast the pointer to this // type. SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, SelectorTy); SelectorAliases[i]->replaceAllUsesWith(SelPtr); SelectorAliases[i]->eraseFromParent(); } // Number of classes defined. Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext), Classes.size())); // Number of categories defined Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext), Categories.size())); // Create an array of classes, then categories, then static object instances Classes.insert(Classes.end(), Categories.begin(), Categories.end()); // NULL-terminated list of static object instances (mainly constant strings) Classes.push_back(Statics); Classes.push_back(NULLPtr); llvm::Constant *ClassList = llvm::ConstantArray::get(ClassListTy, Classes); Elements.push_back(ClassList); // Construct the symbol table llvm::Constant *SymTab= MakeGlobal(SymTabTy, Elements); // The symbol table is contained in a module which has some version-checking // constants llvm::StructType * ModuleTy = llvm::StructType::get(LongTy, LongTy, PtrToInt8Ty, llvm::PointerType::getUnqual(SymTabTy), (RuntimeVersion >= 10) ? IntTy : NULL, NULL); Elements.clear(); // Runtime version, used for ABI compatibility checking. Elements.push_back(llvm::ConstantInt::get(LongTy, RuntimeVersion)); // sizeof(ModuleTy) llvm::TargetData td(&TheModule); Elements.push_back( llvm::ConstantInt::get(LongTy, td.getTypeSizeInBits(ModuleTy) / CGM.getContext().getCharWidth())); // The path to the source file where this module was declared SourceManager &SM = CGM.getContext().getSourceManager(); const FileEntry *mainFile = SM.getFileEntryForID(SM.getMainFileID()); std::string path = std::string(mainFile->getDir()->getName()) + '/' + mainFile->getName(); Elements.push_back(MakeConstantString(path, ".objc_source_file_name")); Elements.push_back(SymTab); if (RuntimeVersion >= 10) switch (CGM.getLangOpts().getGC()) { case LangOptions::GCOnly: Elements.push_back(llvm::ConstantInt::get(IntTy, 2)); break; case LangOptions::NonGC: if (CGM.getLangOpts().ObjCAutoRefCount) Elements.push_back(llvm::ConstantInt::get(IntTy, 1)); else Elements.push_back(llvm::ConstantInt::get(IntTy, 0)); break; case LangOptions::HybridGC: Elements.push_back(llvm::ConstantInt::get(IntTy, 1)); break; } llvm::Value *Module = MakeGlobal(ModuleTy, Elements); // Create the load function calling the runtime entry point with the module // structure llvm::Function * LoadFunction = llvm::Function::Create( llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false), llvm::GlobalValue::InternalLinkage, ".objc_load_function", &TheModule); llvm::BasicBlock *EntryBB = llvm::BasicBlock::Create(VMContext, "entry", LoadFunction); CGBuilderTy Builder(VMContext); Builder.SetInsertPoint(EntryBB); llvm::FunctionType *FT = llvm::FunctionType::get(Builder.getVoidTy(), llvm::PointerType::getUnqual(ModuleTy), true); llvm::Value *Register = CGM.CreateRuntimeFunction(FT, "__objc_exec_class"); Builder.CreateCall(Register, Module); if (!ClassAliases.empty()) { llvm::Type *ArgTypes[2] = {PtrTy, PtrToInt8Ty}; llvm::FunctionType *RegisterAliasTy = llvm::FunctionType::get(Builder.getVoidTy(), ArgTypes, false); llvm::Function *RegisterAlias = llvm::Function::Create( RegisterAliasTy, llvm::GlobalValue::ExternalWeakLinkage, "class_registerAlias_np", &TheModule); llvm::BasicBlock *AliasBB = llvm::BasicBlock::Create(VMContext, "alias", LoadFunction); llvm::BasicBlock *NoAliasBB = llvm::BasicBlock::Create(VMContext, "no_alias", LoadFunction); // Branch based on whether the runtime provided class_registerAlias_np() llvm::Value *HasRegisterAlias = Builder.CreateICmpNE(RegisterAlias, llvm::Constant::getNullValue(RegisterAlias->getType())); Builder.CreateCondBr(HasRegisterAlias, AliasBB, NoAliasBB); // The true branch (has alias registration fucntion): Builder.SetInsertPoint(AliasBB); // Emit alias registration calls: for (std::vector<ClassAliasPair>::iterator iter = ClassAliases.begin(); iter != ClassAliases.end(); ++iter) { llvm::Constant *TheClass = TheModule.getGlobalVariable(("_OBJC_CLASS_" + iter->first).c_str(), true); if (0 != TheClass) { TheClass = llvm::ConstantExpr::getBitCast(TheClass, PtrTy); Builder.CreateCall2(RegisterAlias, TheClass, MakeConstantString(iter->second)); } } // Jump to end: Builder.CreateBr(NoAliasBB); // Missing alias registration function, just return from the function: Builder.SetInsertPoint(NoAliasBB); } Builder.CreateRetVoid(); return LoadFunction; } llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD, const ObjCContainerDecl *CD) { const ObjCCategoryImplDecl *OCD = dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext()); StringRef CategoryName = OCD ? OCD->getName() : ""; StringRef ClassName = CD->getName(); Selector MethodName = OMD->getSelector(); bool isClassMethod = !OMD->isInstanceMethod(); CodeGenTypes &Types = CGM.getTypes(); llvm::FunctionType *MethodTy = Types.GetFunctionType(Types.arrangeObjCMethodDeclaration(OMD)); std::string FunctionName = SymbolNameForMethod(ClassName, CategoryName, MethodName, isClassMethod); llvm::Function *Method = llvm::Function::Create(MethodTy, llvm::GlobalValue::InternalLinkage, FunctionName, &TheModule); return Method; } llvm::Constant *CGObjCGNU::GetPropertyGetFunction() { return GetPropertyFn; } llvm::Constant *CGObjCGNU::GetPropertySetFunction() { return SetPropertyFn; } llvm::Constant *CGObjCGNU::GetOptimizedPropertySetFunction(bool atomic, bool copy) { return 0; } llvm::Constant *CGObjCGNU::GetGetStructFunction() { return GetStructPropertyFn; } llvm::Constant *CGObjCGNU::GetSetStructFunction() { return SetStructPropertyFn; } llvm::Constant *CGObjCGNU::GetCppAtomicObjectFunction() { return 0; } llvm::Constant *CGObjCGNU::EnumerationMutationFunction() { return EnumerationMutationFn; } void CGObjCGNU::EmitSynchronizedStmt(CodeGenFunction &CGF, const ObjCAtSynchronizedStmt &S) { EmitAtSynchronizedStmt(CGF, S, SyncEnterFn, SyncExitFn); } void CGObjCGNU::EmitTryStmt(CodeGenFunction &CGF, const ObjCAtTryStmt &S) { // Unlike the Apple non-fragile runtimes, which also uses // unwind-based zero cost exceptions, the GNU Objective C runtime's // EH support isn't a veneer over C++ EH. Instead, exception // objects are created by __objc_exception_throw and destroyed by // the personality function; this avoids the need for bracketing // catch handlers with calls to __blah_begin_catch/__blah_end_catch // (or even _Unwind_DeleteException), but probably doesn't // interoperate very well with foreign exceptions. // // In Objective-C++ mode, we actually emit something equivalent to the C++ // exception handler. EmitTryCatchStmt(CGF, S, EnterCatchFn, ExitCatchFn, ExceptionReThrowFn); return ; } void CGObjCGNU::EmitThrowStmt(CodeGenFunction &CGF, const ObjCAtThrowStmt &S) { llvm::Value *ExceptionAsObject; if (const Expr *ThrowExpr = S.getThrowExpr()) { llvm::Value *Exception = CGF.EmitObjCThrowOperand(ThrowExpr); ExceptionAsObject = Exception; } else { assert((!CGF.ObjCEHValueStack.empty() && CGF.ObjCEHValueStack.back()) && "Unexpected rethrow outside @catch block."); ExceptionAsObject = CGF.ObjCEHValueStack.back(); } ExceptionAsObject = CGF.Builder.CreateBitCast(ExceptionAsObject, IdTy); // Note: This may have to be an invoke, if we want to support constructs like: // @try { // @throw(obj); // } // @catch(id) ... // // This is effectively turning @throw into an incredibly-expensive goto, but // it may happen as a result of inlining followed by missed optimizations, or // as a result of stupidity. llvm::BasicBlock *UnwindBB = CGF.getInvokeDest(); if (!UnwindBB) { CGF.Builder.CreateCall(ExceptionThrowFn, ExceptionAsObject); CGF.Builder.CreateUnreachable(); } else { CGF.Builder.CreateInvoke(ExceptionThrowFn, UnwindBB, UnwindBB, ExceptionAsObject); } // Clear the insertion point to indicate we are in unreachable code. CGF.Builder.ClearInsertionPoint(); } llvm::Value * CGObjCGNU::EmitObjCWeakRead(CodeGenFunction &CGF, llvm::Value *AddrWeakObj) { CGBuilderTy B = CGF.Builder; AddrWeakObj = EnforceType(B, AddrWeakObj, PtrToIdTy); return B.CreateCall(WeakReadFn, AddrWeakObj); } void CGObjCGNU::EmitObjCWeakAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dst) { CGBuilderTy B = CGF.Builder; src = EnforceType(B, src, IdTy); dst = EnforceType(B, dst, PtrToIdTy); B.CreateCall2(WeakAssignFn, src, dst); } void CGObjCGNU::EmitObjCGlobalAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dst, bool threadlocal) { CGBuilderTy B = CGF.Builder; src = EnforceType(B, src, IdTy); dst = EnforceType(B, dst, PtrToIdTy); if (!threadlocal) B.CreateCall2(GlobalAssignFn, src, dst); else // FIXME. Add threadloca assign API llvm_unreachable("EmitObjCGlobalAssign - Threal Local API NYI"); } void CGObjCGNU::EmitObjCIvarAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dst, llvm::Value *ivarOffset) { CGBuilderTy B = CGF.Builder; src = EnforceType(B, src, IdTy); dst = EnforceType(B, dst, IdTy); B.CreateCall3(IvarAssignFn, src, dst, ivarOffset); } void CGObjCGNU::EmitObjCStrongCastAssign(CodeGenFunction &CGF, llvm::Value *src, llvm::Value *dst) { CGBuilderTy B = CGF.Builder; src = EnforceType(B, src, IdTy); dst = EnforceType(B, dst, PtrToIdTy); B.CreateCall2(StrongCastAssignFn, src, dst); } void CGObjCGNU::EmitGCMemmoveCollectable(CodeGenFunction &CGF, llvm::Value *DestPtr, llvm::Value *SrcPtr, llvm::Value *Size) { CGBuilderTy B = CGF.Builder; DestPtr = EnforceType(B, DestPtr, PtrTy); SrcPtr = EnforceType(B, SrcPtr, PtrTy); B.CreateCall3(MemMoveFn, DestPtr, SrcPtr, Size); } llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable( const ObjCInterfaceDecl *ID, const ObjCIvarDecl *Ivar) { const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString() + '.' + Ivar->getNameAsString(); // Emit the variable and initialize it with what we think the correct value // is. This allows code compiled with non-fragile ivars to work correctly // when linked against code which isn't (most of the time). llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name); if (!IvarOffsetPointer) { // This will cause a run-time crash if we accidentally use it. A value of // 0 would seem more sensible, but will silently overwrite the isa pointer // causing a great deal of confusion. uint64_t Offset = -1; // We can't call ComputeIvarBaseOffset() here if we have the // implementation, because it will create an invalid ASTRecordLayout object // that we are then stuck with forever, so we only initialize the ivar // offset variable with a guess if we only have the interface. The // initializer will be reset later anyway, when we are generating the class // description. if (!CGM.getContext().getObjCImplementation( const_cast<ObjCInterfaceDecl *>(ID))) Offset = ComputeIvarBaseOffset(CGM, ID, Ivar); llvm::ConstantInt *OffsetGuess = llvm::ConstantInt::get(Int32Ty, Offset, /*isSigned*/true); // Don't emit the guess in non-PIC code because the linker will not be able // to replace it with the real version for a library. In non-PIC code you // must compile with the fragile ABI if you want to use ivars from a // GCC-compiled class. if (CGM.getLangOpts().PICLevel || CGM.getLangOpts().PIELevel) { llvm::GlobalVariable *IvarOffsetGV = new llvm::GlobalVariable(TheModule, Int32Ty, false, llvm::GlobalValue::PrivateLinkage, OffsetGuess, Name+".guess"); IvarOffsetPointer = new llvm::GlobalVariable(TheModule, IvarOffsetGV->getType(), false, llvm::GlobalValue::LinkOnceAnyLinkage, IvarOffsetGV, Name); } else { IvarOffsetPointer = new llvm::GlobalVariable(TheModule, llvm::Type::getInt32PtrTy(VMContext), false, llvm::GlobalValue::ExternalLinkage, 0, Name); } } return IvarOffsetPointer; } LValue CGObjCGNU::EmitObjCValueForIvar(CodeGenFunction &CGF, QualType ObjectTy, llvm::Value *BaseValue, const ObjCIvarDecl *Ivar, unsigned CVRQualifiers) { const ObjCInterfaceDecl *ID = ObjectTy->getAs<ObjCObjectType>()->getInterface(); return EmitValueForIvarAtOffset(CGF, ID, BaseValue, Ivar, CVRQualifiers, EmitIvarOffset(CGF, ID, Ivar)); } static const ObjCInterfaceDecl *FindIvarInterface(ASTContext &Context, const ObjCInterfaceDecl *OID, const ObjCIvarDecl *OIVD) { for (const ObjCIvarDecl *next = OID->all_declared_ivar_begin(); next; next = next->getNextIvar()) { if (OIVD == next) return OID; } // Otherwise check in the super class. if (const ObjCInterfaceDecl *Super = OID->getSuperClass()) return FindIvarInterface(Context, Super, OIVD); return 0; } llvm::Value *CGObjCGNU::EmitIvarOffset(CodeGenFunction &CGF, const ObjCInterfaceDecl *Interface, const ObjCIvarDecl *Ivar) { if (CGM.getLangOpts().ObjCNonFragileABI) { Interface = FindIvarInterface(CGM.getContext(), Interface, Ivar); if (RuntimeVersion < 10) return CGF.Builder.CreateZExtOrBitCast( CGF.Builder.CreateLoad(CGF.Builder.CreateLoad( ObjCIvarOffsetVariable(Interface, Ivar), false, "ivar")), PtrDiffTy); std::string name = "__objc_ivar_offset_value_" + Interface->getNameAsString() +"." + Ivar->getNameAsString(); llvm::Value *Offset = TheModule.getGlobalVariable(name); if (!Offset) Offset = new llvm::GlobalVariable(TheModule, IntTy, false, llvm::GlobalValue::LinkOnceAnyLinkage, llvm::Constant::getNullValue(IntTy), name); Offset = CGF.Builder.CreateLoad(Offset); if (Offset->getType() != PtrDiffTy) Offset = CGF.Builder.CreateZExtOrBitCast(Offset, PtrDiffTy); return Offset; } uint64_t Offset = ComputeIvarBaseOffset(CGF.CGM, Interface, Ivar); return llvm::ConstantInt::get(PtrDiffTy, Offset, /*isSigned*/true); } CGObjCRuntime * clang::CodeGen::CreateGNUObjCRuntime(CodeGenModule &CGM) { if (CGM.getLangOpts().ObjCNonFragileABI) return new CGObjCGNUstep(CGM); return new CGObjCGCC(CGM); }