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Diffstat (limited to 'contrib/llvm/tools/clang/lib/CodeGen/CGObjCGNU.cpp')
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diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGObjCGNU.cpp b/contrib/llvm/tools/clang/lib/CodeGen/CGObjCGNU.cpp new file mode 100644 index 0000000..db0bd95 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/CodeGen/CGObjCGNU.cpp @@ -0,0 +1,2671 @@ +//===------- 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); +} |
