CGObjCGNU.cpp revision 208954
1//===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This provides Objective-C code generation targetting the GNU runtime. The 11// class in this file generates structures used by the GNU Objective-C runtime 12// library. These structures are defined in objc/objc.h and objc/objc-api.h in 13// the GNU runtime distribution. 14// 15//===----------------------------------------------------------------------===// 16 17#include "CGObjCRuntime.h" 18#include "CodeGenModule.h" 19#include "CodeGenFunction.h" 20 21#include "clang/AST/ASTContext.h" 22#include "clang/AST/Decl.h" 23#include "clang/AST/DeclObjC.h" 24#include "clang/AST/RecordLayout.h" 25#include "clang/AST/StmtObjC.h" 26 27#include "llvm/Intrinsics.h" 28#include "llvm/Module.h" 29#include "llvm/LLVMContext.h" 30#include "llvm/ADT/SmallVector.h" 31#include "llvm/ADT/StringMap.h" 32#include "llvm/Support/Compiler.h" 33#include "llvm/Target/TargetData.h" 34 35#include <map> 36 37 38using namespace clang; 39using namespace CodeGen; 40using llvm::dyn_cast; 41 42// The version of the runtime that this class targets. Must match the version 43// in the runtime. 44static const int RuntimeVersion = 8; 45static const int NonFragileRuntimeVersion = 9; 46static const int ProtocolVersion = 2; 47static const int NonFragileProtocolVersion = 3; 48 49namespace { 50class CGObjCGNU : public CodeGen::CGObjCRuntime { 51private: 52 CodeGen::CodeGenModule &CGM; 53 llvm::Module &TheModule; 54 const llvm::PointerType *SelectorTy; 55 const llvm::IntegerType *Int8Ty; 56 const llvm::PointerType *PtrToInt8Ty; 57 const llvm::FunctionType *IMPTy; 58 const llvm::PointerType *IdTy; 59 const llvm::PointerType *PtrToIdTy; 60 CanQualType ASTIdTy; 61 const llvm::IntegerType *IntTy; 62 const llvm::PointerType *PtrTy; 63 const llvm::IntegerType *LongTy; 64 const llvm::PointerType *PtrToIntTy; 65 llvm::GlobalAlias *ClassPtrAlias; 66 llvm::GlobalAlias *MetaClassPtrAlias; 67 std::vector<llvm::Constant*> Classes; 68 std::vector<llvm::Constant*> Categories; 69 std::vector<llvm::Constant*> ConstantStrings; 70 llvm::StringMap<llvm::Constant*> ObjCStrings; 71 llvm::Function *LoadFunction; 72 llvm::StringMap<llvm::Constant*> ExistingProtocols; 73 typedef std::pair<std::string, std::string> TypedSelector; 74 std::map<TypedSelector, llvm::GlobalAlias*> TypedSelectors; 75 llvm::StringMap<llvm::GlobalAlias*> UntypedSelectors; 76 // Selectors that we don't emit in GC mode 77 Selector RetainSel, ReleaseSel, AutoreleaseSel; 78 // Functions used for GC. 79 llvm::Constant *IvarAssignFn, *StrongCastAssignFn, *MemMoveFn, *WeakReadFn, 80 *WeakAssignFn, *GlobalAssignFn; 81 // Some zeros used for GEPs in lots of places. 82 llvm::Constant *Zeros[2]; 83 llvm::Constant *NULLPtr; 84 llvm::LLVMContext &VMContext; 85 /// Metadata kind used to tie method lookups to message sends. 86 unsigned msgSendMDKind; 87private: 88 llvm::Constant *GenerateIvarList( 89 const llvm::SmallVectorImpl<llvm::Constant *> &IvarNames, 90 const llvm::SmallVectorImpl<llvm::Constant *> &IvarTypes, 91 const llvm::SmallVectorImpl<llvm::Constant *> &IvarOffsets); 92 llvm::Constant *GenerateMethodList(const std::string &ClassName, 93 const std::string &CategoryName, 94 const llvm::SmallVectorImpl<Selector> &MethodSels, 95 const llvm::SmallVectorImpl<llvm::Constant *> &MethodTypes, 96 bool isClassMethodList); 97 llvm::Constant *GenerateEmptyProtocol(const std::string &ProtocolName); 98 llvm::Constant *GeneratePropertyList(const ObjCImplementationDecl *OID, 99 llvm::SmallVectorImpl<Selector> &InstanceMethodSels, 100 llvm::SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes); 101 llvm::Constant *GenerateProtocolList( 102 const llvm::SmallVectorImpl<std::string> &Protocols); 103 // To ensure that all protocols are seen by the runtime, we add a category on 104 // a class defined in the runtime, declaring no methods, but adopting the 105 // protocols. 106 void GenerateProtocolHolderCategory(void); 107 llvm::Constant *GenerateClassStructure( 108 llvm::Constant *MetaClass, 109 llvm::Constant *SuperClass, 110 unsigned info, 111 const char *Name, 112 llvm::Constant *Version, 113 llvm::Constant *InstanceSize, 114 llvm::Constant *IVars, 115 llvm::Constant *Methods, 116 llvm::Constant *Protocols, 117 llvm::Constant *IvarOffsets, 118 llvm::Constant *Properties, 119 bool isMeta=false); 120 llvm::Constant *GenerateProtocolMethodList( 121 const llvm::SmallVectorImpl<llvm::Constant *> &MethodNames, 122 const llvm::SmallVectorImpl<llvm::Constant *> &MethodTypes); 123 llvm::Constant *MakeConstantString(const std::string &Str, const std::string 124 &Name=""); 125 llvm::Constant *ExportUniqueString(const std::string &Str, const std::string 126 prefix); 127 llvm::Constant *MakeGlobal(const llvm::StructType *Ty, 128 std::vector<llvm::Constant*> &V, llvm::StringRef Name="", 129 llvm::GlobalValue::LinkageTypes linkage=llvm::GlobalValue::InternalLinkage); 130 llvm::Constant *MakeGlobal(const llvm::ArrayType *Ty, 131 std::vector<llvm::Constant*> &V, llvm::StringRef Name="", 132 llvm::GlobalValue::LinkageTypes linkage=llvm::GlobalValue::InternalLinkage); 133 llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID, 134 const ObjCIvarDecl *Ivar); 135 void EmitClassRef(const std::string &className); 136 llvm::Value* EnforceType(CGBuilderTy B, llvm::Value *V, const llvm::Type *Ty){ 137 if (V->getType() == Ty) return V; 138 return B.CreateBitCast(V, Ty); 139 } 140public: 141 CGObjCGNU(CodeGen::CodeGenModule &cgm); 142 virtual llvm::Constant *GenerateConstantString(const StringLiteral *); 143 virtual CodeGen::RValue 144 GenerateMessageSend(CodeGen::CodeGenFunction &CGF, 145 ReturnValueSlot Return, 146 QualType ResultType, 147 Selector Sel, 148 llvm::Value *Receiver, 149 const CallArgList &CallArgs, 150 const ObjCInterfaceDecl *Class, 151 const ObjCMethodDecl *Method); 152 virtual CodeGen::RValue 153 GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF, 154 ReturnValueSlot Return, 155 QualType ResultType, 156 Selector Sel, 157 const ObjCInterfaceDecl *Class, 158 bool isCategoryImpl, 159 llvm::Value *Receiver, 160 bool IsClassMessage, 161 const CallArgList &CallArgs, 162 const ObjCMethodDecl *Method); 163 virtual llvm::Value *GetClass(CGBuilderTy &Builder, 164 const ObjCInterfaceDecl *OID); 165 virtual llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel); 166 virtual llvm::Value *GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl 167 *Method); 168 169 virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD, 170 const ObjCContainerDecl *CD); 171 virtual void GenerateCategory(const ObjCCategoryImplDecl *CMD); 172 virtual void GenerateClass(const ObjCImplementationDecl *ClassDecl); 173 virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder, 174 const ObjCProtocolDecl *PD); 175 virtual void GenerateProtocol(const ObjCProtocolDecl *PD); 176 virtual llvm::Function *ModuleInitFunction(); 177 virtual llvm::Function *GetPropertyGetFunction(); 178 virtual llvm::Function *GetPropertySetFunction(); 179 virtual llvm::Function *GetCopyStructFunction(); 180 virtual llvm::Constant *EnumerationMutationFunction(); 181 182 virtual void EmitTryOrSynchronizedStmt(CodeGen::CodeGenFunction &CGF, 183 const Stmt &S); 184 virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF, 185 const ObjCAtThrowStmt &S); 186 virtual llvm::Value * EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF, 187 llvm::Value *AddrWeakObj); 188 virtual void EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF, 189 llvm::Value *src, llvm::Value *dst); 190 virtual void EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF, 191 llvm::Value *src, llvm::Value *dest); 192 virtual void EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF, 193 llvm::Value *src, llvm::Value *dest, 194 llvm::Value *ivarOffset); 195 virtual void EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF, 196 llvm::Value *src, llvm::Value *dest); 197 virtual void EmitGCMemmoveCollectable(CodeGen::CodeGenFunction &CGF, 198 llvm::Value *DestPtr, 199 llvm::Value *SrcPtr, 200 QualType Ty); 201 virtual LValue EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF, 202 QualType ObjectTy, 203 llvm::Value *BaseValue, 204 const ObjCIvarDecl *Ivar, 205 unsigned CVRQualifiers); 206 virtual llvm::Value *EmitIvarOffset(CodeGen::CodeGenFunction &CGF, 207 const ObjCInterfaceDecl *Interface, 208 const ObjCIvarDecl *Ivar); 209}; 210} // end anonymous namespace 211 212 213/// Emits a reference to a dummy variable which is emitted with each class. 214/// This ensures that a linker error will be generated when trying to link 215/// together modules where a referenced class is not defined. 216void CGObjCGNU::EmitClassRef(const std::string &className) { 217 std::string symbolRef = "__objc_class_ref_" + className; 218 // Don't emit two copies of the same symbol 219 if (TheModule.getGlobalVariable(symbolRef)) 220 return; 221 std::string symbolName = "__objc_class_name_" + className; 222 llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(symbolName); 223 if (!ClassSymbol) { 224 ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false, 225 llvm::GlobalValue::ExternalLinkage, 0, symbolName); 226 } 227 new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true, 228 llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef); 229} 230 231static std::string SymbolNameForMethod(const std::string &ClassName, const 232 std::string &CategoryName, const std::string &MethodName, bool isClassMethod) 233{ 234 std::string MethodNameColonStripped = MethodName; 235 std::replace(MethodNameColonStripped.begin(), MethodNameColonStripped.end(), 236 ':', '_'); 237 return std::string(isClassMethod ? "_c_" : "_i_") + ClassName + "_" + 238 CategoryName + "_" + MethodNameColonStripped; 239} 240static std::string MangleSelectorTypes(const std::string &TypeString) { 241 std::string Mangled = TypeString; 242 // Simple mangling to avoid breaking when we mix JIT / static code. 243 // Not part of the ABI, subject to change without notice. 244 std::replace(Mangled.begin(), Mangled.end(), '@', '_'); 245 std::replace(Mangled.begin(), Mangled.end(), ':', 'J'); 246 std::replace(Mangled.begin(), Mangled.end(), '*', 'e'); 247 std::replace(Mangled.begin(), Mangled.end(), '#', 'E'); 248 std::replace(Mangled.begin(), Mangled.end(), ':', 'j'); 249 std::replace(Mangled.begin(), Mangled.end(), '(', 'g'); 250 std::replace(Mangled.begin(), Mangled.end(), ')', 'G'); 251 std::replace(Mangled.begin(), Mangled.end(), '[', 'h'); 252 std::replace(Mangled.begin(), Mangled.end(), ']', 'H'); 253 return Mangled; 254} 255 256CGObjCGNU::CGObjCGNU(CodeGen::CodeGenModule &cgm) 257 : CGM(cgm), TheModule(CGM.getModule()), ClassPtrAlias(0), 258 MetaClassPtrAlias(0), VMContext(cgm.getLLVMContext()) { 259 260 msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend"); 261 262 IntTy = cast<llvm::IntegerType>( 263 CGM.getTypes().ConvertType(CGM.getContext().IntTy)); 264 LongTy = cast<llvm::IntegerType>( 265 CGM.getTypes().ConvertType(CGM.getContext().LongTy)); 266 267 Int8Ty = llvm::Type::getInt8Ty(VMContext); 268 // C string type. Used in lots of places. 269 PtrToInt8Ty = llvm::PointerType::getUnqual(Int8Ty); 270 271 Zeros[0] = llvm::ConstantInt::get(LongTy, 0); 272 Zeros[1] = Zeros[0]; 273 NULLPtr = llvm::ConstantPointerNull::get(PtrToInt8Ty); 274 // Get the selector Type. 275 QualType selTy = CGM.getContext().getObjCSelType(); 276 if (QualType() == selTy) { 277 SelectorTy = PtrToInt8Ty; 278 } else { 279 SelectorTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(selTy)); 280 } 281 282 PtrToIntTy = llvm::PointerType::getUnqual(IntTy); 283 PtrTy = PtrToInt8Ty; 284 285 // Object type 286 ASTIdTy = CGM.getContext().getCanonicalType(CGM.getContext().getObjCIdType()); 287 if (QualType() == ASTIdTy) { 288 IdTy = PtrToInt8Ty; 289 } else { 290 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy)); 291 } 292 PtrToIdTy = llvm::PointerType::getUnqual(IdTy); 293 294 // IMP type 295 std::vector<const llvm::Type*> IMPArgs; 296 IMPArgs.push_back(IdTy); 297 IMPArgs.push_back(SelectorTy); 298 IMPTy = llvm::FunctionType::get(IdTy, IMPArgs, true); 299 300 if (CGM.getLangOptions().getGCMode() != LangOptions::NonGC) { 301 // Get selectors needed in GC mode 302 RetainSel = GetNullarySelector("retain", CGM.getContext()); 303 ReleaseSel = GetNullarySelector("release", CGM.getContext()); 304 AutoreleaseSel = GetNullarySelector("autorelease", CGM.getContext()); 305 306 // Get functions needed in GC mode 307 308 // id objc_assign_ivar(id, id, ptrdiff_t); 309 std::vector<const llvm::Type*> Args(1, IdTy); 310 Args.push_back(PtrToIdTy); 311 // FIXME: ptrdiff_t 312 Args.push_back(LongTy); 313 llvm::FunctionType *FTy = llvm::FunctionType::get(IdTy, Args, false); 314 IvarAssignFn = CGM.CreateRuntimeFunction(FTy, "objc_assign_ivar"); 315 // id objc_assign_strongCast (id, id*) 316 Args.pop_back(); 317 FTy = llvm::FunctionType::get(IdTy, Args, false); 318 StrongCastAssignFn = 319 CGM.CreateRuntimeFunction(FTy, "objc_assign_strongCast"); 320 // id objc_assign_global(id, id*); 321 FTy = llvm::FunctionType::get(IdTy, Args, false); 322 GlobalAssignFn = CGM.CreateRuntimeFunction(FTy, "objc_assign_global"); 323 // id objc_assign_weak(id, id*); 324 FTy = llvm::FunctionType::get(IdTy, Args, false); 325 WeakAssignFn = CGM.CreateRuntimeFunction(FTy, "objc_assign_weak"); 326 // id objc_read_weak(id*); 327 Args.clear(); 328 Args.push_back(PtrToIdTy); 329 FTy = llvm::FunctionType::get(IdTy, Args, false); 330 WeakReadFn = CGM.CreateRuntimeFunction(FTy, "objc_read_weak"); 331 // void *objc_memmove_collectable(void*, void *, size_t); 332 Args.clear(); 333 Args.push_back(PtrToInt8Ty); 334 Args.push_back(PtrToInt8Ty); 335 // FIXME: size_t 336 Args.push_back(LongTy); 337 FTy = llvm::FunctionType::get(IdTy, Args, false); 338 MemMoveFn = CGM.CreateRuntimeFunction(FTy, "objc_memmove_collectable"); 339 } 340} 341 342// This has to perform the lookup every time, since posing and related 343// techniques can modify the name -> class mapping. 344llvm::Value *CGObjCGNU::GetClass(CGBuilderTy &Builder, 345 const ObjCInterfaceDecl *OID) { 346 llvm::Value *ClassName = CGM.GetAddrOfConstantCString(OID->getNameAsString()); 347 // With the incompatible ABI, this will need to be replaced with a direct 348 // reference to the class symbol. For the compatible nonfragile ABI we are 349 // still performing this lookup at run time but emitting the symbol for the 350 // class externally so that we can make the switch later. 351 EmitClassRef(OID->getNameAsString()); 352 ClassName = Builder.CreateStructGEP(ClassName, 0); 353 354 std::vector<const llvm::Type*> Params(1, PtrToInt8Ty); 355 llvm::Constant *ClassLookupFn = 356 CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, 357 Params, 358 true), 359 "objc_lookup_class"); 360 return Builder.CreateCall(ClassLookupFn, ClassName); 361} 362 363llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel) { 364 llvm::GlobalAlias *&US = UntypedSelectors[Sel.getAsString()]; 365 if (US == 0) 366 US = new llvm::GlobalAlias(llvm::PointerType::getUnqual(SelectorTy), 367 llvm::GlobalValue::PrivateLinkage, 368 ".objc_untyped_selector_alias"+Sel.getAsString(), 369 NULL, &TheModule); 370 371 return Builder.CreateLoad(US); 372} 373 374llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl 375 *Method) { 376 377 std::string SelName = Method->getSelector().getAsString(); 378 std::string SelTypes; 379 CGM.getContext().getObjCEncodingForMethodDecl(Method, SelTypes); 380 // Typed selectors 381 TypedSelector Selector = TypedSelector(SelName, 382 SelTypes); 383 384 // If it's already cached, return it. 385 if (TypedSelectors[Selector]) { 386 return Builder.CreateLoad(TypedSelectors[Selector]); 387 } 388 389 // If it isn't, cache it. 390 llvm::GlobalAlias *Sel = new llvm::GlobalAlias( 391 llvm::PointerType::getUnqual(SelectorTy), 392 llvm::GlobalValue::PrivateLinkage, ".objc_selector_alias" + SelName, 393 NULL, &TheModule); 394 TypedSelectors[Selector] = Sel; 395 396 return Builder.CreateLoad(Sel); 397} 398 399llvm::Constant *CGObjCGNU::MakeConstantString(const std::string &Str, 400 const std::string &Name) { 401 llvm::Constant *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str()); 402 return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2); 403} 404llvm::Constant *CGObjCGNU::ExportUniqueString(const std::string &Str, 405 const std::string prefix) { 406 std::string name = prefix + Str; 407 llvm::Constant *ConstStr = TheModule.getGlobalVariable(name); 408 if (!ConstStr) { 409 llvm::Constant *value = llvm::ConstantArray::get(VMContext, Str, true); 410 ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true, 411 llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str); 412 } 413 return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2); 414} 415 416llvm::Constant *CGObjCGNU::MakeGlobal(const llvm::StructType *Ty, 417 std::vector<llvm::Constant*> &V, llvm::StringRef Name, 418 llvm::GlobalValue::LinkageTypes linkage) { 419 llvm::Constant *C = llvm::ConstantStruct::get(Ty, V); 420 return new llvm::GlobalVariable(TheModule, Ty, false, 421 llvm::GlobalValue::InternalLinkage, C, Name); 422} 423 424llvm::Constant *CGObjCGNU::MakeGlobal(const llvm::ArrayType *Ty, 425 std::vector<llvm::Constant*> &V, llvm::StringRef Name, 426 llvm::GlobalValue::LinkageTypes linkage) { 427 llvm::Constant *C = llvm::ConstantArray::get(Ty, V); 428 return new llvm::GlobalVariable(TheModule, Ty, false, 429 llvm::GlobalValue::InternalLinkage, C, Name); 430} 431 432/// Generate an NSConstantString object. 433llvm::Constant *CGObjCGNU::GenerateConstantString(const StringLiteral *SL) { 434 435 std::string Str(SL->getStrData(), SL->getByteLength()); 436 437 // Look for an existing one 438 llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str); 439 if (old != ObjCStrings.end()) 440 return old->getValue(); 441 442 std::vector<llvm::Constant*> Ivars; 443 Ivars.push_back(NULLPtr); 444 Ivars.push_back(MakeConstantString(Str)); 445 Ivars.push_back(llvm::ConstantInt::get(IntTy, Str.size())); 446 llvm::Constant *ObjCStr = MakeGlobal( 447 llvm::StructType::get(VMContext, PtrToInt8Ty, PtrToInt8Ty, IntTy, NULL), 448 Ivars, ".objc_str"); 449 ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty); 450 ObjCStrings[Str] = ObjCStr; 451 ConstantStrings.push_back(ObjCStr); 452 return ObjCStr; 453} 454 455///Generates a message send where the super is the receiver. This is a message 456///send to self with special delivery semantics indicating which class's method 457///should be called. 458CodeGen::RValue 459CGObjCGNU::GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF, 460 ReturnValueSlot Return, 461 QualType ResultType, 462 Selector Sel, 463 const ObjCInterfaceDecl *Class, 464 bool isCategoryImpl, 465 llvm::Value *Receiver, 466 bool IsClassMessage, 467 const CallArgList &CallArgs, 468 const ObjCMethodDecl *Method) { 469 if (CGM.getLangOptions().getGCMode() != LangOptions::NonGC) { 470 if (Sel == RetainSel || Sel == AutoreleaseSel) { 471 return RValue::get(Receiver); 472 } 473 if (Sel == ReleaseSel) { 474 return RValue::get(0); 475 } 476 } 477 478 CGBuilderTy &Builder = CGF.Builder; 479 llvm::Value *cmd = GetSelector(Builder, Sel); 480 481 482 CallArgList ActualArgs; 483 484 ActualArgs.push_back( 485 std::make_pair(RValue::get(Builder.CreateBitCast(Receiver, IdTy)), 486 ASTIdTy)); 487 ActualArgs.push_back(std::make_pair(RValue::get(cmd), 488 CGF.getContext().getObjCSelType())); 489 ActualArgs.insert(ActualArgs.end(), CallArgs.begin(), CallArgs.end()); 490 491 CodeGenTypes &Types = CGM.getTypes(); 492 const CGFunctionInfo &FnInfo = Types.getFunctionInfo(ResultType, ActualArgs, 493 FunctionType::ExtInfo()); 494 const llvm::FunctionType *impType = 495 Types.GetFunctionType(FnInfo, Method ? Method->isVariadic() : false); 496 497 llvm::Value *ReceiverClass = 0; 498 if (isCategoryImpl) { 499 llvm::Constant *classLookupFunction = 0; 500 std::vector<const llvm::Type*> Params; 501 Params.push_back(PtrTy); 502 if (IsClassMessage) { 503 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get( 504 IdTy, Params, true), "objc_get_meta_class"); 505 } else { 506 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get( 507 IdTy, Params, true), "objc_get_class"); 508 } 509 ReceiverClass = Builder.CreateCall(classLookupFunction, 510 MakeConstantString(Class->getNameAsString())); 511 } else { 512 // Set up global aliases for the metaclass or class pointer if they do not 513 // already exist. These will are forward-references which will be set to 514 // pointers to the class and metaclass structure created for the runtime 515 // load function. To send a message to super, we look up the value of the 516 // super_class pointer from either the class or metaclass structure. 517 if (IsClassMessage) { 518 if (!MetaClassPtrAlias) { 519 MetaClassPtrAlias = new llvm::GlobalAlias(IdTy, 520 llvm::GlobalValue::InternalLinkage, ".objc_metaclass_ref" + 521 Class->getNameAsString(), NULL, &TheModule); 522 } 523 ReceiverClass = MetaClassPtrAlias; 524 } else { 525 if (!ClassPtrAlias) { 526 ClassPtrAlias = new llvm::GlobalAlias(IdTy, 527 llvm::GlobalValue::InternalLinkage, ".objc_class_ref" + 528 Class->getNameAsString(), NULL, &TheModule); 529 } 530 ReceiverClass = ClassPtrAlias; 531 } 532 } 533 // Cast the pointer to a simplified version of the class structure 534 ReceiverClass = Builder.CreateBitCast(ReceiverClass, 535 llvm::PointerType::getUnqual( 536 llvm::StructType::get(VMContext, IdTy, IdTy, NULL))); 537 // Get the superclass pointer 538 ReceiverClass = Builder.CreateStructGEP(ReceiverClass, 1); 539 // Load the superclass pointer 540 ReceiverClass = Builder.CreateLoad(ReceiverClass); 541 // Construct the structure used to look up the IMP 542 llvm::StructType *ObjCSuperTy = llvm::StructType::get(VMContext, 543 Receiver->getType(), IdTy, NULL); 544 llvm::Value *ObjCSuper = Builder.CreateAlloca(ObjCSuperTy); 545 546 Builder.CreateStore(Receiver, Builder.CreateStructGEP(ObjCSuper, 0)); 547 Builder.CreateStore(ReceiverClass, Builder.CreateStructGEP(ObjCSuper, 1)); 548 549 // Get the IMP 550 std::vector<const llvm::Type*> Params; 551 Params.push_back(llvm::PointerType::getUnqual(ObjCSuperTy)); 552 Params.push_back(SelectorTy); 553 554 llvm::Value *lookupArgs[] = {ObjCSuper, cmd}; 555 llvm::Value *imp; 556 557 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) { 558 // The lookup function returns a slot, which can be safely cached. 559 llvm::Type *SlotTy = llvm::StructType::get(VMContext, PtrTy, PtrTy, PtrTy, 560 IntTy, llvm::PointerType::getUnqual(impType), NULL); 561 562 llvm::Constant *lookupFunction = 563 CGM.CreateRuntimeFunction(llvm::FunctionType::get( 564 llvm::PointerType::getUnqual(SlotTy), Params, true), 565 "objc_slot_lookup_super"); 566 567 llvm::CallInst *slot = Builder.CreateCall(lookupFunction, lookupArgs, 568 lookupArgs+2); 569 slot->setOnlyReadsMemory(); 570 571 imp = Builder.CreateLoad(Builder.CreateStructGEP(slot, 4)); 572 } else { 573 llvm::Constant *lookupFunction = 574 CGM.CreateRuntimeFunction(llvm::FunctionType::get( 575 llvm::PointerType::getUnqual(impType), Params, true), 576 "objc_msg_lookup_super"); 577 imp = Builder.CreateCall(lookupFunction, lookupArgs, lookupArgs+2); 578 } 579 580 llvm::Value *impMD[] = { 581 llvm::MDString::get(VMContext, Sel.getAsString()), 582 llvm::MDString::get(VMContext, Class->getSuperClass()->getNameAsString()), 583 llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), IsClassMessage) 584 }; 585 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD, 3); 586 587 llvm::Instruction *call; 588 RValue msgRet = CGF.EmitCall(FnInfo, imp, Return, ActualArgs, 589 0, &call); 590 call->setMetadata(msgSendMDKind, node); 591 return msgRet; 592} 593 594/// Generate code for a message send expression. 595CodeGen::RValue 596CGObjCGNU::GenerateMessageSend(CodeGen::CodeGenFunction &CGF, 597 ReturnValueSlot Return, 598 QualType ResultType, 599 Selector Sel, 600 llvm::Value *Receiver, 601 const CallArgList &CallArgs, 602 const ObjCInterfaceDecl *Class, 603 const ObjCMethodDecl *Method) { 604 // Strip out message sends to retain / release in GC mode 605 if (CGM.getLangOptions().getGCMode() != LangOptions::NonGC) { 606 if (Sel == RetainSel || Sel == AutoreleaseSel) { 607 return RValue::get(Receiver); 608 } 609 if (Sel == ReleaseSel) { 610 return RValue::get(0); 611 } 612 } 613 614 CGBuilderTy &Builder = CGF.Builder; 615 616 // If the return type is something that goes in an integer register, the 617 // runtime will handle 0 returns. For other cases, we fill in the 0 value 618 // ourselves. 619 // 620 // The language spec says the result of this kind of message send is 621 // undefined, but lots of people seem to have forgotten to read that 622 // paragraph and insist on sending messages to nil that have structure 623 // returns. With GCC, this generates a random return value (whatever happens 624 // to be on the stack / in those registers at the time) on most platforms, 625 // and generates a SegV on SPARC. With LLVM it corrupts the stack. 626 bool isPointerSizedReturn = false; 627 if (ResultType->isAnyPointerType() || ResultType->isIntegralType() || 628 ResultType->isVoidType()) 629 isPointerSizedReturn = true; 630 631 llvm::BasicBlock *startBB = 0; 632 llvm::BasicBlock *messageBB = 0; 633 llvm::BasicBlock *continueBB = 0; 634 635 if (!isPointerSizedReturn) { 636 startBB = Builder.GetInsertBlock(); 637 messageBB = CGF.createBasicBlock("msgSend"); 638 continueBB = CGF.createBasicBlock("continue"); 639 640 llvm::Value *isNil = Builder.CreateICmpEQ(Receiver, 641 llvm::Constant::getNullValue(Receiver->getType())); 642 Builder.CreateCondBr(isNil, continueBB, messageBB); 643 CGF.EmitBlock(messageBB); 644 } 645 646 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy)); 647 llvm::Value *cmd; 648 if (Method) 649 cmd = GetSelector(Builder, Method); 650 else 651 cmd = GetSelector(Builder, Sel); 652 CallArgList ActualArgs; 653 654 Receiver = Builder.CreateBitCast(Receiver, IdTy); 655 ActualArgs.push_back( 656 std::make_pair(RValue::get(Receiver), ASTIdTy)); 657 ActualArgs.push_back(std::make_pair(RValue::get(cmd), 658 CGF.getContext().getObjCSelType())); 659 ActualArgs.insert(ActualArgs.end(), CallArgs.begin(), CallArgs.end()); 660 661 CodeGenTypes &Types = CGM.getTypes(); 662 const CGFunctionInfo &FnInfo = Types.getFunctionInfo(ResultType, ActualArgs, 663 FunctionType::ExtInfo()); 664 const llvm::FunctionType *impType = 665 Types.GetFunctionType(FnInfo, Method ? Method->isVariadic() : false); 666 667 llvm::Value *impMD[] = { 668 llvm::MDString::get(VMContext, Sel.getAsString()), 669 llvm::MDString::get(VMContext, Class ? Class->getNameAsString() :""), 670 llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), Class!=0) 671 }; 672 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD, 3); 673 674 675 llvm::Value *imp; 676 // For sender-aware dispatch, we pass the sender as the third argument to a 677 // lookup function. When sending messages from C code, the sender is nil. 678 // objc_msg_lookup_sender(id *receiver, SEL selector, id sender); 679 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) { 680 681 std::vector<const llvm::Type*> Params; 682 llvm::Value *ReceiverPtr = CGF.CreateTempAlloca(Receiver->getType()); 683 Builder.CreateStore(Receiver, ReceiverPtr); 684 Params.push_back(ReceiverPtr->getType()); 685 Params.push_back(SelectorTy); 686 llvm::Value *self; 687 688 if (isa<ObjCMethodDecl>(CGF.CurFuncDecl)) { 689 self = CGF.LoadObjCSelf(); 690 } else { 691 self = llvm::ConstantPointerNull::get(IdTy); 692 } 693 694 Params.push_back(self->getType()); 695 696 // The lookup function returns a slot, which can be safely cached. 697 llvm::Type *SlotTy = llvm::StructType::get(VMContext, PtrTy, PtrTy, PtrTy, 698 IntTy, llvm::PointerType::getUnqual(impType), NULL); 699 llvm::Constant *lookupFunction = 700 CGM.CreateRuntimeFunction(llvm::FunctionType::get( 701 llvm::PointerType::getUnqual(SlotTy), Params, true), 702 "objc_msg_lookup_sender"); 703 704 // The lookup function is guaranteed not to capture the receiver pointer. 705 if (llvm::Function *LookupFn = dyn_cast<llvm::Function>(lookupFunction)) { 706 LookupFn->setDoesNotCapture(1); 707 } 708 709 llvm::CallInst *slot = 710 Builder.CreateCall3(lookupFunction, ReceiverPtr, cmd, self); 711 slot->setOnlyReadsMemory(); 712 slot->setMetadata(msgSendMDKind, node); 713 714 imp = Builder.CreateLoad(Builder.CreateStructGEP(slot, 4)); 715 716 // The lookup function may have changed the receiver, so make sure we use 717 // the new one. 718 ActualArgs[0] = 719 std::make_pair(RValue::get(Builder.CreateLoad(ReceiverPtr)), ASTIdTy); 720 } else { 721 std::vector<const llvm::Type*> Params; 722 Params.push_back(Receiver->getType()); 723 Params.push_back(SelectorTy); 724 llvm::Constant *lookupFunction = 725 CGM.CreateRuntimeFunction(llvm::FunctionType::get( 726 llvm::PointerType::getUnqual(impType), Params, true), 727 "objc_msg_lookup"); 728 729 imp = Builder.CreateCall2(lookupFunction, Receiver, cmd); 730 cast<llvm::CallInst>(imp)->setMetadata(msgSendMDKind, node); 731 } 732 llvm::Instruction *call; 733 RValue msgRet = CGF.EmitCall(FnInfo, imp, Return, ActualArgs, 734 0, &call); 735 call->setMetadata(msgSendMDKind, node); 736 737 738 if (!isPointerSizedReturn) { 739 messageBB = CGF.Builder.GetInsertBlock(); 740 CGF.Builder.CreateBr(continueBB); 741 CGF.EmitBlock(continueBB); 742 if (msgRet.isScalar()) { 743 llvm::Value *v = msgRet.getScalarVal(); 744 llvm::PHINode *phi = Builder.CreatePHI(v->getType()); 745 phi->addIncoming(v, messageBB); 746 phi->addIncoming(llvm::Constant::getNullValue(v->getType()), startBB); 747 msgRet = RValue::get(phi); 748 } else if (msgRet.isAggregate()) { 749 llvm::Value *v = msgRet.getAggregateAddr(); 750 llvm::PHINode *phi = Builder.CreatePHI(v->getType()); 751 const llvm::PointerType *RetTy = cast<llvm::PointerType>(v->getType()); 752 llvm::AllocaInst *NullVal = 753 CGF.CreateTempAlloca(RetTy->getElementType(), "null"); 754 CGF.InitTempAlloca(NullVal, 755 llvm::Constant::getNullValue(RetTy->getElementType())); 756 phi->addIncoming(v, messageBB); 757 phi->addIncoming(NullVal, startBB); 758 msgRet = RValue::getAggregate(phi); 759 } else /* isComplex() */ { 760 std::pair<llvm::Value*,llvm::Value*> v = msgRet.getComplexVal(); 761 llvm::PHINode *phi = Builder.CreatePHI(v.first->getType()); 762 phi->addIncoming(v.first, messageBB); 763 phi->addIncoming(llvm::Constant::getNullValue(v.first->getType()), 764 startBB); 765 llvm::PHINode *phi2 = Builder.CreatePHI(v.second->getType()); 766 phi2->addIncoming(v.second, messageBB); 767 phi2->addIncoming(llvm::Constant::getNullValue(v.second->getType()), 768 startBB); 769 msgRet = RValue::getComplex(phi, phi2); 770 } 771 } 772 return msgRet; 773} 774 775/// Generates a MethodList. Used in construction of a objc_class and 776/// objc_category structures. 777llvm::Constant *CGObjCGNU::GenerateMethodList(const std::string &ClassName, 778 const std::string &CategoryName, 779 const llvm::SmallVectorImpl<Selector> &MethodSels, 780 const llvm::SmallVectorImpl<llvm::Constant *> &MethodTypes, 781 bool isClassMethodList) { 782 if (MethodSels.empty()) 783 return NULLPtr; 784 // Get the method structure type. 785 llvm::StructType *ObjCMethodTy = llvm::StructType::get(VMContext, 786 PtrToInt8Ty, // Really a selector, but the runtime creates it us. 787 PtrToInt8Ty, // Method types 788 llvm::PointerType::getUnqual(IMPTy), //Method pointer 789 NULL); 790 std::vector<llvm::Constant*> Methods; 791 std::vector<llvm::Constant*> Elements; 792 for (unsigned int i = 0, e = MethodTypes.size(); i < e; ++i) { 793 Elements.clear(); 794 if (llvm::Constant *Method = 795 TheModule.getFunction(SymbolNameForMethod(ClassName, CategoryName, 796 MethodSels[i].getAsString(), 797 isClassMethodList))) { 798 llvm::Constant *C = MakeConstantString(MethodSels[i].getAsString()); 799 Elements.push_back(C); 800 Elements.push_back(MethodTypes[i]); 801 Method = llvm::ConstantExpr::getBitCast(Method, 802 llvm::PointerType::getUnqual(IMPTy)); 803 Elements.push_back(Method); 804 Methods.push_back(llvm::ConstantStruct::get(ObjCMethodTy, Elements)); 805 } 806 } 807 808 // Array of method structures 809 llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodTy, 810 Methods.size()); 811 llvm::Constant *MethodArray = llvm::ConstantArray::get(ObjCMethodArrayTy, 812 Methods); 813 814 // Structure containing list pointer, array and array count 815 llvm::SmallVector<const llvm::Type*, 16> ObjCMethodListFields; 816 llvm::PATypeHolder OpaqueNextTy = llvm::OpaqueType::get(VMContext); 817 llvm::Type *NextPtrTy = llvm::PointerType::getUnqual(OpaqueNextTy); 818 llvm::StructType *ObjCMethodListTy = llvm::StructType::get(VMContext, 819 NextPtrTy, 820 IntTy, 821 ObjCMethodArrayTy, 822 NULL); 823 // Refine next pointer type to concrete type 824 llvm::cast<llvm::OpaqueType>( 825 OpaqueNextTy.get())->refineAbstractTypeTo(ObjCMethodListTy); 826 ObjCMethodListTy = llvm::cast<llvm::StructType>(OpaqueNextTy.get()); 827 828 Methods.clear(); 829 Methods.push_back(llvm::ConstantPointerNull::get( 830 llvm::PointerType::getUnqual(ObjCMethodListTy))); 831 Methods.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 832 MethodTypes.size())); 833 Methods.push_back(MethodArray); 834 835 // Create an instance of the structure 836 return MakeGlobal(ObjCMethodListTy, Methods, ".objc_method_list"); 837} 838 839/// Generates an IvarList. Used in construction of a objc_class. 840llvm::Constant *CGObjCGNU::GenerateIvarList( 841 const llvm::SmallVectorImpl<llvm::Constant *> &IvarNames, 842 const llvm::SmallVectorImpl<llvm::Constant *> &IvarTypes, 843 const llvm::SmallVectorImpl<llvm::Constant *> &IvarOffsets) { 844 if (IvarNames.size() == 0) 845 return NULLPtr; 846 // Get the method structure type. 847 llvm::StructType *ObjCIvarTy = llvm::StructType::get(VMContext, 848 PtrToInt8Ty, 849 PtrToInt8Ty, 850 IntTy, 851 NULL); 852 std::vector<llvm::Constant*> Ivars; 853 std::vector<llvm::Constant*> Elements; 854 for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) { 855 Elements.clear(); 856 Elements.push_back(IvarNames[i]); 857 Elements.push_back(IvarTypes[i]); 858 Elements.push_back(IvarOffsets[i]); 859 Ivars.push_back(llvm::ConstantStruct::get(ObjCIvarTy, Elements)); 860 } 861 862 // Array of method structures 863 llvm::ArrayType *ObjCIvarArrayTy = llvm::ArrayType::get(ObjCIvarTy, 864 IvarNames.size()); 865 866 867 Elements.clear(); 868 Elements.push_back(llvm::ConstantInt::get(IntTy, (int)IvarNames.size())); 869 Elements.push_back(llvm::ConstantArray::get(ObjCIvarArrayTy, Ivars)); 870 // Structure containing array and array count 871 llvm::StructType *ObjCIvarListTy = llvm::StructType::get(VMContext, IntTy, 872 ObjCIvarArrayTy, 873 NULL); 874 875 // Create an instance of the structure 876 return MakeGlobal(ObjCIvarListTy, Elements, ".objc_ivar_list"); 877} 878 879/// Generate a class structure 880llvm::Constant *CGObjCGNU::GenerateClassStructure( 881 llvm::Constant *MetaClass, 882 llvm::Constant *SuperClass, 883 unsigned info, 884 const char *Name, 885 llvm::Constant *Version, 886 llvm::Constant *InstanceSize, 887 llvm::Constant *IVars, 888 llvm::Constant *Methods, 889 llvm::Constant *Protocols, 890 llvm::Constant *IvarOffsets, 891 llvm::Constant *Properties, 892 bool isMeta) { 893 // Set up the class structure 894 // Note: Several of these are char*s when they should be ids. This is 895 // because the runtime performs this translation on load. 896 // 897 // Fields marked New ABI are part of the GNUstep runtime. We emit them 898 // anyway; the classes will still work with the GNU runtime, they will just 899 // be ignored. 900 llvm::StructType *ClassTy = llvm::StructType::get(VMContext, 901 PtrToInt8Ty, // class_pointer 902 PtrToInt8Ty, // super_class 903 PtrToInt8Ty, // name 904 LongTy, // version 905 LongTy, // info 906 LongTy, // instance_size 907 IVars->getType(), // ivars 908 Methods->getType(), // methods 909 // These are all filled in by the runtime, so we pretend 910 PtrTy, // dtable 911 PtrTy, // subclass_list 912 PtrTy, // sibling_class 913 PtrTy, // protocols 914 PtrTy, // gc_object_type 915 // New ABI: 916 LongTy, // abi_version 917 IvarOffsets->getType(), // ivar_offsets 918 Properties->getType(), // properties 919 NULL); 920 llvm::Constant *Zero = llvm::ConstantInt::get(LongTy, 0); 921 // Fill in the structure 922 std::vector<llvm::Constant*> Elements; 923 Elements.push_back(llvm::ConstantExpr::getBitCast(MetaClass, PtrToInt8Ty)); 924 Elements.push_back(SuperClass); 925 Elements.push_back(MakeConstantString(Name, ".class_name")); 926 Elements.push_back(Zero); 927 Elements.push_back(llvm::ConstantInt::get(LongTy, info)); 928 Elements.push_back(InstanceSize); 929 Elements.push_back(IVars); 930 Elements.push_back(Methods); 931 Elements.push_back(NULLPtr); 932 Elements.push_back(NULLPtr); 933 Elements.push_back(NULLPtr); 934 Elements.push_back(llvm::ConstantExpr::getBitCast(Protocols, PtrTy)); 935 Elements.push_back(NULLPtr); 936 Elements.push_back(Zero); 937 Elements.push_back(IvarOffsets); 938 Elements.push_back(Properties); 939 // Create an instance of the structure 940 // This is now an externally visible symbol, so that we can speed up class 941 // messages in the next ABI. 942 return MakeGlobal(ClassTy, Elements, (isMeta ? "_OBJC_METACLASS_": 943 "_OBJC_CLASS_") + std::string(Name), llvm::GlobalValue::ExternalLinkage); 944} 945 946llvm::Constant *CGObjCGNU::GenerateProtocolMethodList( 947 const llvm::SmallVectorImpl<llvm::Constant *> &MethodNames, 948 const llvm::SmallVectorImpl<llvm::Constant *> &MethodTypes) { 949 // Get the method structure type. 950 llvm::StructType *ObjCMethodDescTy = llvm::StructType::get(VMContext, 951 PtrToInt8Ty, // Really a selector, but the runtime does the casting for us. 952 PtrToInt8Ty, 953 NULL); 954 std::vector<llvm::Constant*> Methods; 955 std::vector<llvm::Constant*> Elements; 956 for (unsigned int i = 0, e = MethodTypes.size() ; i < e ; i++) { 957 Elements.clear(); 958 Elements.push_back(MethodNames[i]); 959 Elements.push_back(MethodTypes[i]); 960 Methods.push_back(llvm::ConstantStruct::get(ObjCMethodDescTy, Elements)); 961 } 962 llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodDescTy, 963 MethodNames.size()); 964 llvm::Constant *Array = llvm::ConstantArray::get(ObjCMethodArrayTy, 965 Methods); 966 llvm::StructType *ObjCMethodDescListTy = llvm::StructType::get(VMContext, 967 IntTy, ObjCMethodArrayTy, NULL); 968 Methods.clear(); 969 Methods.push_back(llvm::ConstantInt::get(IntTy, MethodNames.size())); 970 Methods.push_back(Array); 971 return MakeGlobal(ObjCMethodDescListTy, Methods, ".objc_method_list"); 972} 973 974// Create the protocol list structure used in classes, categories and so on 975llvm::Constant *CGObjCGNU::GenerateProtocolList( 976 const llvm::SmallVectorImpl<std::string> &Protocols) { 977 llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrToInt8Ty, 978 Protocols.size()); 979 llvm::StructType *ProtocolListTy = llvm::StructType::get(VMContext, 980 PtrTy, //Should be a recurisve pointer, but it's always NULL here. 981 LongTy,//FIXME: Should be size_t 982 ProtocolArrayTy, 983 NULL); 984 std::vector<llvm::Constant*> Elements; 985 for (const std::string *iter = Protocols.begin(), *endIter = Protocols.end(); 986 iter != endIter ; iter++) { 987 llvm::Constant *protocol = 0; 988 llvm::StringMap<llvm::Constant*>::iterator value = 989 ExistingProtocols.find(*iter); 990 if (value == ExistingProtocols.end()) { 991 protocol = GenerateEmptyProtocol(*iter); 992 } else { 993 protocol = value->getValue(); 994 } 995 llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(protocol, 996 PtrToInt8Ty); 997 Elements.push_back(Ptr); 998 } 999 llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy, 1000 Elements); 1001 Elements.clear(); 1002 Elements.push_back(NULLPtr); 1003 Elements.push_back(llvm::ConstantInt::get(LongTy, Protocols.size())); 1004 Elements.push_back(ProtocolArray); 1005 return MakeGlobal(ProtocolListTy, Elements, ".objc_protocol_list"); 1006} 1007 1008llvm::Value *CGObjCGNU::GenerateProtocolRef(CGBuilderTy &Builder, 1009 const ObjCProtocolDecl *PD) { 1010 llvm::Value *protocol = ExistingProtocols[PD->getNameAsString()]; 1011 const llvm::Type *T = 1012 CGM.getTypes().ConvertType(CGM.getContext().getObjCProtoType()); 1013 return Builder.CreateBitCast(protocol, llvm::PointerType::getUnqual(T)); 1014} 1015 1016llvm::Constant *CGObjCGNU::GenerateEmptyProtocol( 1017 const std::string &ProtocolName) { 1018 llvm::SmallVector<std::string, 0> EmptyStringVector; 1019 llvm::SmallVector<llvm::Constant*, 0> EmptyConstantVector; 1020 1021 llvm::Constant *ProtocolList = GenerateProtocolList(EmptyStringVector); 1022 llvm::Constant *MethodList = 1023 GenerateProtocolMethodList(EmptyConstantVector, EmptyConstantVector); 1024 // Protocols are objects containing lists of the methods implemented and 1025 // protocols adopted. 1026 llvm::StructType *ProtocolTy = llvm::StructType::get(VMContext, IdTy, 1027 PtrToInt8Ty, 1028 ProtocolList->getType(), 1029 MethodList->getType(), 1030 MethodList->getType(), 1031 MethodList->getType(), 1032 MethodList->getType(), 1033 NULL); 1034 std::vector<llvm::Constant*> Elements; 1035 // The isa pointer must be set to a magic number so the runtime knows it's 1036 // the correct layout. 1037 int Version = CGM.getContext().getLangOptions().ObjCNonFragileABI ? 1038 NonFragileProtocolVersion : ProtocolVersion; 1039 Elements.push_back(llvm::ConstantExpr::getIntToPtr( 1040 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Version), IdTy)); 1041 Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name")); 1042 Elements.push_back(ProtocolList); 1043 Elements.push_back(MethodList); 1044 Elements.push_back(MethodList); 1045 Elements.push_back(MethodList); 1046 Elements.push_back(MethodList); 1047 return MakeGlobal(ProtocolTy, Elements, ".objc_protocol"); 1048} 1049 1050void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) { 1051 ASTContext &Context = CGM.getContext(); 1052 std::string ProtocolName = PD->getNameAsString(); 1053 llvm::SmallVector<std::string, 16> Protocols; 1054 for (ObjCProtocolDecl::protocol_iterator PI = PD->protocol_begin(), 1055 E = PD->protocol_end(); PI != E; ++PI) 1056 Protocols.push_back((*PI)->getNameAsString()); 1057 llvm::SmallVector<llvm::Constant*, 16> InstanceMethodNames; 1058 llvm::SmallVector<llvm::Constant*, 16> InstanceMethodTypes; 1059 llvm::SmallVector<llvm::Constant*, 16> OptionalInstanceMethodNames; 1060 llvm::SmallVector<llvm::Constant*, 16> OptionalInstanceMethodTypes; 1061 for (ObjCProtocolDecl::instmeth_iterator iter = PD->instmeth_begin(), 1062 E = PD->instmeth_end(); iter != E; iter++) { 1063 std::string TypeStr; 1064 Context.getObjCEncodingForMethodDecl(*iter, TypeStr); 1065 if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) { 1066 InstanceMethodNames.push_back( 1067 MakeConstantString((*iter)->getSelector().getAsString())); 1068 InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); 1069 } else { 1070 OptionalInstanceMethodNames.push_back( 1071 MakeConstantString((*iter)->getSelector().getAsString())); 1072 OptionalInstanceMethodTypes.push_back(MakeConstantString(TypeStr)); 1073 } 1074 } 1075 // Collect information about class methods: 1076 llvm::SmallVector<llvm::Constant*, 16> ClassMethodNames; 1077 llvm::SmallVector<llvm::Constant*, 16> ClassMethodTypes; 1078 llvm::SmallVector<llvm::Constant*, 16> OptionalClassMethodNames; 1079 llvm::SmallVector<llvm::Constant*, 16> OptionalClassMethodTypes; 1080 for (ObjCProtocolDecl::classmeth_iterator 1081 iter = PD->classmeth_begin(), endIter = PD->classmeth_end(); 1082 iter != endIter ; iter++) { 1083 std::string TypeStr; 1084 Context.getObjCEncodingForMethodDecl((*iter),TypeStr); 1085 if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) { 1086 ClassMethodNames.push_back( 1087 MakeConstantString((*iter)->getSelector().getAsString())); 1088 ClassMethodTypes.push_back(MakeConstantString(TypeStr)); 1089 } else { 1090 OptionalClassMethodNames.push_back( 1091 MakeConstantString((*iter)->getSelector().getAsString())); 1092 OptionalClassMethodTypes.push_back(MakeConstantString(TypeStr)); 1093 } 1094 } 1095 1096 llvm::Constant *ProtocolList = GenerateProtocolList(Protocols); 1097 llvm::Constant *InstanceMethodList = 1098 GenerateProtocolMethodList(InstanceMethodNames, InstanceMethodTypes); 1099 llvm::Constant *ClassMethodList = 1100 GenerateProtocolMethodList(ClassMethodNames, ClassMethodTypes); 1101 llvm::Constant *OptionalInstanceMethodList = 1102 GenerateProtocolMethodList(OptionalInstanceMethodNames, 1103 OptionalInstanceMethodTypes); 1104 llvm::Constant *OptionalClassMethodList = 1105 GenerateProtocolMethodList(OptionalClassMethodNames, 1106 OptionalClassMethodTypes); 1107 1108 // Property metadata: name, attributes, isSynthesized, setter name, setter 1109 // types, getter name, getter types. 1110 // The isSynthesized value is always set to 0 in a protocol. It exists to 1111 // simplify the runtime library by allowing it to use the same data 1112 // structures for protocol metadata everywhere. 1113 llvm::StructType *PropertyMetadataTy = llvm::StructType::get(VMContext, 1114 PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, 1115 PtrToInt8Ty, NULL); 1116 std::vector<llvm::Constant*> Properties; 1117 std::vector<llvm::Constant*> OptionalProperties; 1118 1119 // Add all of the property methods need adding to the method list and to the 1120 // property metadata list. 1121 for (ObjCContainerDecl::prop_iterator 1122 iter = PD->prop_begin(), endIter = PD->prop_end(); 1123 iter != endIter ; iter++) { 1124 std::vector<llvm::Constant*> Fields; 1125 ObjCPropertyDecl *property = (*iter); 1126 1127 Fields.push_back(MakeConstantString(property->getNameAsString())); 1128 Fields.push_back(llvm::ConstantInt::get(Int8Ty, 1129 property->getPropertyAttributes())); 1130 Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0)); 1131 if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) { 1132 std::string TypeStr; 1133 Context.getObjCEncodingForMethodDecl(getter,TypeStr); 1134 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); 1135 InstanceMethodTypes.push_back(TypeEncoding); 1136 Fields.push_back(MakeConstantString(getter->getSelector().getAsString())); 1137 Fields.push_back(TypeEncoding); 1138 } else { 1139 Fields.push_back(NULLPtr); 1140 Fields.push_back(NULLPtr); 1141 } 1142 if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) { 1143 std::string TypeStr; 1144 Context.getObjCEncodingForMethodDecl(setter,TypeStr); 1145 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); 1146 InstanceMethodTypes.push_back(TypeEncoding); 1147 Fields.push_back(MakeConstantString(setter->getSelector().getAsString())); 1148 Fields.push_back(TypeEncoding); 1149 } else { 1150 Fields.push_back(NULLPtr); 1151 Fields.push_back(NULLPtr); 1152 } 1153 if (property->getPropertyImplementation() == ObjCPropertyDecl::Optional) { 1154 OptionalProperties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); 1155 } else { 1156 Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); 1157 } 1158 } 1159 llvm::Constant *PropertyArray = llvm::ConstantArray::get( 1160 llvm::ArrayType::get(PropertyMetadataTy, Properties.size()), Properties); 1161 llvm::Constant* PropertyListInitFields[] = 1162 {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray}; 1163 1164 llvm::Constant *PropertyListInit = 1165 llvm::ConstantStruct::get(VMContext, PropertyListInitFields, 3, false); 1166 llvm::Constant *PropertyList = new llvm::GlobalVariable(TheModule, 1167 PropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage, 1168 PropertyListInit, ".objc_property_list"); 1169 1170 llvm::Constant *OptionalPropertyArray = 1171 llvm::ConstantArray::get(llvm::ArrayType::get(PropertyMetadataTy, 1172 OptionalProperties.size()) , OptionalProperties); 1173 llvm::Constant* OptionalPropertyListInitFields[] = { 1174 llvm::ConstantInt::get(IntTy, OptionalProperties.size()), NULLPtr, 1175 OptionalPropertyArray }; 1176 1177 llvm::Constant *OptionalPropertyListInit = 1178 llvm::ConstantStruct::get(VMContext, OptionalPropertyListInitFields, 3, false); 1179 llvm::Constant *OptionalPropertyList = new llvm::GlobalVariable(TheModule, 1180 OptionalPropertyListInit->getType(), false, 1181 llvm::GlobalValue::InternalLinkage, OptionalPropertyListInit, 1182 ".objc_property_list"); 1183 1184 // Protocols are objects containing lists of the methods implemented and 1185 // protocols adopted. 1186 llvm::StructType *ProtocolTy = llvm::StructType::get(VMContext, IdTy, 1187 PtrToInt8Ty, 1188 ProtocolList->getType(), 1189 InstanceMethodList->getType(), 1190 ClassMethodList->getType(), 1191 OptionalInstanceMethodList->getType(), 1192 OptionalClassMethodList->getType(), 1193 PropertyList->getType(), 1194 OptionalPropertyList->getType(), 1195 NULL); 1196 std::vector<llvm::Constant*> Elements; 1197 // The isa pointer must be set to a magic number so the runtime knows it's 1198 // the correct layout. 1199 int Version = CGM.getContext().getLangOptions().ObjCNonFragileABI ? 1200 NonFragileProtocolVersion : ProtocolVersion; 1201 Elements.push_back(llvm::ConstantExpr::getIntToPtr( 1202 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Version), IdTy)); 1203 Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name")); 1204 Elements.push_back(ProtocolList); 1205 Elements.push_back(InstanceMethodList); 1206 Elements.push_back(ClassMethodList); 1207 Elements.push_back(OptionalInstanceMethodList); 1208 Elements.push_back(OptionalClassMethodList); 1209 Elements.push_back(PropertyList); 1210 Elements.push_back(OptionalPropertyList); 1211 ExistingProtocols[ProtocolName] = 1212 llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolTy, Elements, 1213 ".objc_protocol"), IdTy); 1214} 1215void CGObjCGNU::GenerateProtocolHolderCategory(void) { 1216 // Collect information about instance methods 1217 llvm::SmallVector<Selector, 1> MethodSels; 1218 llvm::SmallVector<llvm::Constant*, 1> MethodTypes; 1219 1220 std::vector<llvm::Constant*> Elements; 1221 const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack"; 1222 const std::string CategoryName = "AnotherHack"; 1223 Elements.push_back(MakeConstantString(CategoryName)); 1224 Elements.push_back(MakeConstantString(ClassName)); 1225 // Instance method list 1226 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( 1227 ClassName, CategoryName, MethodSels, MethodTypes, false), PtrTy)); 1228 // Class method list 1229 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( 1230 ClassName, CategoryName, MethodSels, MethodTypes, true), PtrTy)); 1231 // Protocol list 1232 llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrTy, 1233 ExistingProtocols.size()); 1234 llvm::StructType *ProtocolListTy = llvm::StructType::get(VMContext, 1235 PtrTy, //Should be a recurisve pointer, but it's always NULL here. 1236 LongTy,//FIXME: Should be size_t 1237 ProtocolArrayTy, 1238 NULL); 1239 std::vector<llvm::Constant*> ProtocolElements; 1240 for (llvm::StringMapIterator<llvm::Constant*> iter = 1241 ExistingProtocols.begin(), endIter = ExistingProtocols.end(); 1242 iter != endIter ; iter++) { 1243 llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(iter->getValue(), 1244 PtrTy); 1245 ProtocolElements.push_back(Ptr); 1246 } 1247 llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy, 1248 ProtocolElements); 1249 ProtocolElements.clear(); 1250 ProtocolElements.push_back(NULLPtr); 1251 ProtocolElements.push_back(llvm::ConstantInt::get(LongTy, 1252 ExistingProtocols.size())); 1253 ProtocolElements.push_back(ProtocolArray); 1254 Elements.push_back(llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolListTy, 1255 ProtocolElements, ".objc_protocol_list"), PtrTy)); 1256 Categories.push_back(llvm::ConstantExpr::getBitCast( 1257 MakeGlobal(llvm::StructType::get(VMContext, PtrToInt8Ty, PtrToInt8Ty, 1258 PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy)); 1259} 1260 1261void CGObjCGNU::GenerateCategory(const ObjCCategoryImplDecl *OCD) { 1262 std::string ClassName = OCD->getClassInterface()->getNameAsString(); 1263 std::string CategoryName = OCD->getNameAsString(); 1264 // Collect information about instance methods 1265 llvm::SmallVector<Selector, 16> InstanceMethodSels; 1266 llvm::SmallVector<llvm::Constant*, 16> InstanceMethodTypes; 1267 for (ObjCCategoryImplDecl::instmeth_iterator 1268 iter = OCD->instmeth_begin(), endIter = OCD->instmeth_end(); 1269 iter != endIter ; iter++) { 1270 InstanceMethodSels.push_back((*iter)->getSelector()); 1271 std::string TypeStr; 1272 CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr); 1273 InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); 1274 } 1275 1276 // Collect information about class methods 1277 llvm::SmallVector<Selector, 16> ClassMethodSels; 1278 llvm::SmallVector<llvm::Constant*, 16> ClassMethodTypes; 1279 for (ObjCCategoryImplDecl::classmeth_iterator 1280 iter = OCD->classmeth_begin(), endIter = OCD->classmeth_end(); 1281 iter != endIter ; iter++) { 1282 ClassMethodSels.push_back((*iter)->getSelector()); 1283 std::string TypeStr; 1284 CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr); 1285 ClassMethodTypes.push_back(MakeConstantString(TypeStr)); 1286 } 1287 1288 // Collect the names of referenced protocols 1289 llvm::SmallVector<std::string, 16> Protocols; 1290 const ObjCCategoryDecl *CatDecl = OCD->getCategoryDecl(); 1291 const ObjCList<ObjCProtocolDecl> &Protos = CatDecl->getReferencedProtocols(); 1292 for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(), 1293 E = Protos.end(); I != E; ++I) 1294 Protocols.push_back((*I)->getNameAsString()); 1295 1296 std::vector<llvm::Constant*> Elements; 1297 Elements.push_back(MakeConstantString(CategoryName)); 1298 Elements.push_back(MakeConstantString(ClassName)); 1299 // Instance method list 1300 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( 1301 ClassName, CategoryName, InstanceMethodSels, InstanceMethodTypes, 1302 false), PtrTy)); 1303 // Class method list 1304 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList( 1305 ClassName, CategoryName, ClassMethodSels, ClassMethodTypes, true), 1306 PtrTy)); 1307 // Protocol list 1308 Elements.push_back(llvm::ConstantExpr::getBitCast( 1309 GenerateProtocolList(Protocols), PtrTy)); 1310 Categories.push_back(llvm::ConstantExpr::getBitCast( 1311 MakeGlobal(llvm::StructType::get(VMContext, PtrToInt8Ty, PtrToInt8Ty, 1312 PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy)); 1313} 1314 1315llvm::Constant *CGObjCGNU::GeneratePropertyList(const ObjCImplementationDecl *OID, 1316 llvm::SmallVectorImpl<Selector> &InstanceMethodSels, 1317 llvm::SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes) { 1318 ASTContext &Context = CGM.getContext(); 1319 // 1320 // Property metadata: name, attributes, isSynthesized, setter name, setter 1321 // types, getter name, getter types. 1322 llvm::StructType *PropertyMetadataTy = llvm::StructType::get(VMContext, 1323 PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, 1324 PtrToInt8Ty, NULL); 1325 std::vector<llvm::Constant*> Properties; 1326 1327 1328 // Add all of the property methods need adding to the method list and to the 1329 // property metadata list. 1330 for (ObjCImplDecl::propimpl_iterator 1331 iter = OID->propimpl_begin(), endIter = OID->propimpl_end(); 1332 iter != endIter ; iter++) { 1333 std::vector<llvm::Constant*> Fields; 1334 ObjCPropertyDecl *property = (*iter)->getPropertyDecl(); 1335 ObjCPropertyImplDecl *propertyImpl = *iter; 1336 bool isSynthesized = (propertyImpl->getPropertyImplementation() == 1337 ObjCPropertyImplDecl::Synthesize); 1338 1339 Fields.push_back(MakeConstantString(property->getNameAsString())); 1340 Fields.push_back(llvm::ConstantInt::get(Int8Ty, 1341 property->getPropertyAttributes())); 1342 Fields.push_back(llvm::ConstantInt::get(Int8Ty, isSynthesized)); 1343 if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) { 1344 std::string TypeStr; 1345 Context.getObjCEncodingForMethodDecl(getter,TypeStr); 1346 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); 1347 if (isSynthesized) { 1348 InstanceMethodTypes.push_back(TypeEncoding); 1349 InstanceMethodSels.push_back(getter->getSelector()); 1350 } 1351 Fields.push_back(MakeConstantString(getter->getSelector().getAsString())); 1352 Fields.push_back(TypeEncoding); 1353 } else { 1354 Fields.push_back(NULLPtr); 1355 Fields.push_back(NULLPtr); 1356 } 1357 if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) { 1358 std::string TypeStr; 1359 Context.getObjCEncodingForMethodDecl(setter,TypeStr); 1360 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr); 1361 if (isSynthesized) { 1362 InstanceMethodTypes.push_back(TypeEncoding); 1363 InstanceMethodSels.push_back(setter->getSelector()); 1364 } 1365 Fields.push_back(MakeConstantString(setter->getSelector().getAsString())); 1366 Fields.push_back(TypeEncoding); 1367 } else { 1368 Fields.push_back(NULLPtr); 1369 Fields.push_back(NULLPtr); 1370 } 1371 Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields)); 1372 } 1373 llvm::ArrayType *PropertyArrayTy = 1374 llvm::ArrayType::get(PropertyMetadataTy, Properties.size()); 1375 llvm::Constant *PropertyArray = llvm::ConstantArray::get(PropertyArrayTy, 1376 Properties); 1377 llvm::Constant* PropertyListInitFields[] = 1378 {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray}; 1379 1380 llvm::Constant *PropertyListInit = 1381 llvm::ConstantStruct::get(VMContext, PropertyListInitFields, 3, false); 1382 return new llvm::GlobalVariable(TheModule, PropertyListInit->getType(), false, 1383 llvm::GlobalValue::InternalLinkage, PropertyListInit, 1384 ".objc_property_list"); 1385} 1386 1387void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) { 1388 ASTContext &Context = CGM.getContext(); 1389 1390 // Get the superclass name. 1391 const ObjCInterfaceDecl * SuperClassDecl = 1392 OID->getClassInterface()->getSuperClass(); 1393 std::string SuperClassName; 1394 if (SuperClassDecl) { 1395 SuperClassName = SuperClassDecl->getNameAsString(); 1396 EmitClassRef(SuperClassName); 1397 } 1398 1399 // Get the class name 1400 ObjCInterfaceDecl *ClassDecl = 1401 const_cast<ObjCInterfaceDecl *>(OID->getClassInterface()); 1402 std::string ClassName = ClassDecl->getNameAsString(); 1403 // Emit the symbol that is used to generate linker errors if this class is 1404 // referenced in other modules but not declared. 1405 std::string classSymbolName = "__objc_class_name_" + ClassName; 1406 if (llvm::GlobalVariable *symbol = 1407 TheModule.getGlobalVariable(classSymbolName)) { 1408 symbol->setInitializer(llvm::ConstantInt::get(LongTy, 0)); 1409 } else { 1410 new llvm::GlobalVariable(TheModule, LongTy, false, 1411 llvm::GlobalValue::ExternalLinkage, llvm::ConstantInt::get(LongTy, 0), 1412 classSymbolName); 1413 } 1414 1415 // Get the size of instances. 1416 int instanceSize = Context.getASTObjCImplementationLayout(OID).getSize() / 8; 1417 1418 // Collect information about instance variables. 1419 llvm::SmallVector<llvm::Constant*, 16> IvarNames; 1420 llvm::SmallVector<llvm::Constant*, 16> IvarTypes; 1421 llvm::SmallVector<llvm::Constant*, 16> IvarOffsets; 1422 1423 std::vector<llvm::Constant*> IvarOffsetValues; 1424 1425 int superInstanceSize = !SuperClassDecl ? 0 : 1426 Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize() / 8; 1427 // For non-fragile ivars, set the instance size to 0 - {the size of just this 1428 // class}. The runtime will then set this to the correct value on load. 1429 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) { 1430 instanceSize = 0 - (instanceSize - superInstanceSize); 1431 } 1432 1433 // Collect declared and synthesized ivars. 1434 llvm::SmallVector<ObjCIvarDecl*, 16> OIvars; 1435 CGM.getContext().ShallowCollectObjCIvars(ClassDecl, OIvars); 1436 1437 for (unsigned i = 0, e = OIvars.size(); i != e; ++i) { 1438 ObjCIvarDecl *IVD = OIvars[i]; 1439 // Store the name 1440 IvarNames.push_back(MakeConstantString(IVD->getNameAsString())); 1441 // Get the type encoding for this ivar 1442 std::string TypeStr; 1443 Context.getObjCEncodingForType(IVD->getType(), TypeStr); 1444 IvarTypes.push_back(MakeConstantString(TypeStr)); 1445 // Get the offset 1446 uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD); 1447 uint64_t Offset = BaseOffset; 1448 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) { 1449 Offset = BaseOffset - superInstanceSize; 1450 } 1451 IvarOffsets.push_back( 1452 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Offset)); 1453 IvarOffsetValues.push_back(new llvm::GlobalVariable(TheModule, IntTy, 1454 false, llvm::GlobalValue::ExternalLinkage, 1455 llvm::ConstantInt::get(IntTy, BaseOffset), 1456 "__objc_ivar_offset_value_" + ClassName +"." + 1457 IVD->getNameAsString())); 1458 } 1459 llvm::Constant *IvarOffsetArrayInit = 1460 llvm::ConstantArray::get(llvm::ArrayType::get(PtrToIntTy, 1461 IvarOffsetValues.size()), IvarOffsetValues); 1462 llvm::GlobalVariable *IvarOffsetArray = new llvm::GlobalVariable(TheModule, 1463 IvarOffsetArrayInit->getType(), false, 1464 llvm::GlobalValue::InternalLinkage, IvarOffsetArrayInit, 1465 ".ivar.offsets"); 1466 1467 // Collect information about instance methods 1468 llvm::SmallVector<Selector, 16> InstanceMethodSels; 1469 llvm::SmallVector<llvm::Constant*, 16> InstanceMethodTypes; 1470 for (ObjCImplementationDecl::instmeth_iterator 1471 iter = OID->instmeth_begin(), endIter = OID->instmeth_end(); 1472 iter != endIter ; iter++) { 1473 InstanceMethodSels.push_back((*iter)->getSelector()); 1474 std::string TypeStr; 1475 Context.getObjCEncodingForMethodDecl((*iter),TypeStr); 1476 InstanceMethodTypes.push_back(MakeConstantString(TypeStr)); 1477 } 1478 1479 llvm::Constant *Properties = GeneratePropertyList(OID, InstanceMethodSels, 1480 InstanceMethodTypes); 1481 1482 1483 // Collect information about class methods 1484 llvm::SmallVector<Selector, 16> ClassMethodSels; 1485 llvm::SmallVector<llvm::Constant*, 16> ClassMethodTypes; 1486 for (ObjCImplementationDecl::classmeth_iterator 1487 iter = OID->classmeth_begin(), endIter = OID->classmeth_end(); 1488 iter != endIter ; iter++) { 1489 ClassMethodSels.push_back((*iter)->getSelector()); 1490 std::string TypeStr; 1491 Context.getObjCEncodingForMethodDecl((*iter),TypeStr); 1492 ClassMethodTypes.push_back(MakeConstantString(TypeStr)); 1493 } 1494 // Collect the names of referenced protocols 1495 llvm::SmallVector<std::string, 16> Protocols; 1496 const ObjCList<ObjCProtocolDecl> &Protos =ClassDecl->getReferencedProtocols(); 1497 for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(), 1498 E = Protos.end(); I != E; ++I) 1499 Protocols.push_back((*I)->getNameAsString()); 1500 1501 1502 1503 // Get the superclass pointer. 1504 llvm::Constant *SuperClass; 1505 if (!SuperClassName.empty()) { 1506 SuperClass = MakeConstantString(SuperClassName, ".super_class_name"); 1507 } else { 1508 SuperClass = llvm::ConstantPointerNull::get(PtrToInt8Ty); 1509 } 1510 // Empty vector used to construct empty method lists 1511 llvm::SmallVector<llvm::Constant*, 1> empty; 1512 // Generate the method and instance variable lists 1513 llvm::Constant *MethodList = GenerateMethodList(ClassName, "", 1514 InstanceMethodSels, InstanceMethodTypes, false); 1515 llvm::Constant *ClassMethodList = GenerateMethodList(ClassName, "", 1516 ClassMethodSels, ClassMethodTypes, true); 1517 llvm::Constant *IvarList = GenerateIvarList(IvarNames, IvarTypes, 1518 IvarOffsets); 1519 // Irrespective of whether we are compiling for a fragile or non-fragile ABI, 1520 // we emit a symbol containing the offset for each ivar in the class. This 1521 // allows code compiled for the non-Fragile ABI to inherit from code compiled 1522 // for the legacy ABI, without causing problems. The converse is also 1523 // possible, but causes all ivar accesses to be fragile. 1524 int i = 0; 1525 // Offset pointer for getting at the correct field in the ivar list when 1526 // setting up the alias. These are: The base address for the global, the 1527 // ivar array (second field), the ivar in this list (set for each ivar), and 1528 // the offset (third field in ivar structure) 1529 const llvm::Type *IndexTy = llvm::Type::getInt32Ty(VMContext); 1530 llvm::Constant *offsetPointerIndexes[] = {Zeros[0], 1531 llvm::ConstantInt::get(IndexTy, 1), 0, 1532 llvm::ConstantInt::get(IndexTy, 2) }; 1533 1534 for (ObjCInterfaceDecl::ivar_iterator iter = ClassDecl->ivar_begin(), 1535 endIter = ClassDecl->ivar_end() ; iter != endIter ; iter++) { 1536 const std::string Name = "__objc_ivar_offset_" + ClassName + '.' 1537 +(*iter)->getNameAsString(); 1538 offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, i++); 1539 // Get the correct ivar field 1540 llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr( 1541 IvarList, offsetPointerIndexes, 4); 1542 // Get the existing alias, if one exists. 1543 llvm::GlobalVariable *offset = TheModule.getNamedGlobal(Name); 1544 if (offset) { 1545 offset->setInitializer(offsetValue); 1546 // If this is the real definition, change its linkage type so that 1547 // different modules will use this one, rather than their private 1548 // copy. 1549 offset->setLinkage(llvm::GlobalValue::ExternalLinkage); 1550 } else { 1551 // Add a new alias if there isn't one already. 1552 offset = new llvm::GlobalVariable(TheModule, offsetValue->getType(), 1553 false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name); 1554 } 1555 } 1556 //Generate metaclass for class methods 1557 llvm::Constant *MetaClassStruct = GenerateClassStructure(NULLPtr, 1558 NULLPtr, 0x12L, ClassName.c_str(), 0, Zeros[0], GenerateIvarList( 1559 empty, empty, empty), ClassMethodList, NULLPtr, NULLPtr, NULLPtr, true); 1560 1561 // Generate the class structure 1562 llvm::Constant *ClassStruct = 1563 GenerateClassStructure(MetaClassStruct, SuperClass, 0x11L, 1564 ClassName.c_str(), 0, 1565 llvm::ConstantInt::get(LongTy, instanceSize), IvarList, 1566 MethodList, GenerateProtocolList(Protocols), IvarOffsetArray, 1567 Properties); 1568 1569 // Resolve the class aliases, if they exist. 1570 if (ClassPtrAlias) { 1571 ClassPtrAlias->setAliasee( 1572 llvm::ConstantExpr::getBitCast(ClassStruct, IdTy)); 1573 ClassPtrAlias = 0; 1574 } 1575 if (MetaClassPtrAlias) { 1576 MetaClassPtrAlias->setAliasee( 1577 llvm::ConstantExpr::getBitCast(MetaClassStruct, IdTy)); 1578 MetaClassPtrAlias = 0; 1579 } 1580 1581 // Add class structure to list to be added to the symtab later 1582 ClassStruct = llvm::ConstantExpr::getBitCast(ClassStruct, PtrToInt8Ty); 1583 Classes.push_back(ClassStruct); 1584} 1585 1586 1587llvm::Function *CGObjCGNU::ModuleInitFunction() { 1588 // Only emit an ObjC load function if no Objective-C stuff has been called 1589 if (Classes.empty() && Categories.empty() && ConstantStrings.empty() && 1590 ExistingProtocols.empty() && TypedSelectors.empty() && 1591 UntypedSelectors.empty()) 1592 return NULL; 1593 1594 // Add all referenced protocols to a category. 1595 GenerateProtocolHolderCategory(); 1596 1597 const llvm::StructType *SelStructTy = dyn_cast<llvm::StructType>( 1598 SelectorTy->getElementType()); 1599 const llvm::Type *SelStructPtrTy = SelectorTy; 1600 bool isSelOpaque = false; 1601 if (SelStructTy == 0) { 1602 SelStructTy = llvm::StructType::get(VMContext, PtrToInt8Ty, 1603 PtrToInt8Ty, NULL); 1604 SelStructPtrTy = llvm::PointerType::getUnqual(SelStructTy); 1605 isSelOpaque = true; 1606 } 1607 1608 // Name the ObjC types to make the IR a bit easier to read 1609 TheModule.addTypeName(".objc_selector", SelStructPtrTy); 1610 TheModule.addTypeName(".objc_id", IdTy); 1611 TheModule.addTypeName(".objc_imp", IMPTy); 1612 1613 std::vector<llvm::Constant*> Elements; 1614 llvm::Constant *Statics = NULLPtr; 1615 // Generate statics list: 1616 if (ConstantStrings.size()) { 1617 llvm::ArrayType *StaticsArrayTy = llvm::ArrayType::get(PtrToInt8Ty, 1618 ConstantStrings.size() + 1); 1619 ConstantStrings.push_back(NULLPtr); 1620 1621 llvm::StringRef StringClass = CGM.getLangOptions().ObjCConstantStringClass; 1622 if (StringClass.empty()) StringClass = "NXConstantString"; 1623 Elements.push_back(MakeConstantString(StringClass, 1624 ".objc_static_class_name")); 1625 Elements.push_back(llvm::ConstantArray::get(StaticsArrayTy, 1626 ConstantStrings)); 1627 llvm::StructType *StaticsListTy = 1628 llvm::StructType::get(VMContext, PtrToInt8Ty, StaticsArrayTy, NULL); 1629 llvm::Type *StaticsListPtrTy = 1630 llvm::PointerType::getUnqual(StaticsListTy); 1631 Statics = MakeGlobal(StaticsListTy, Elements, ".objc_statics"); 1632 llvm::ArrayType *StaticsListArrayTy = 1633 llvm::ArrayType::get(StaticsListPtrTy, 2); 1634 Elements.clear(); 1635 Elements.push_back(Statics); 1636 Elements.push_back(llvm::Constant::getNullValue(StaticsListPtrTy)); 1637 Statics = MakeGlobal(StaticsListArrayTy, Elements, ".objc_statics_ptr"); 1638 Statics = llvm::ConstantExpr::getBitCast(Statics, PtrTy); 1639 } 1640 // Array of classes, categories, and constant objects 1641 llvm::ArrayType *ClassListTy = llvm::ArrayType::get(PtrToInt8Ty, 1642 Classes.size() + Categories.size() + 2); 1643 llvm::StructType *SymTabTy = llvm::StructType::get(VMContext, 1644 LongTy, SelStructPtrTy, 1645 llvm::Type::getInt16Ty(VMContext), 1646 llvm::Type::getInt16Ty(VMContext), 1647 ClassListTy, NULL); 1648 1649 Elements.clear(); 1650 // Pointer to an array of selectors used in this module. 1651 std::vector<llvm::Constant*> Selectors; 1652 for (std::map<TypedSelector, llvm::GlobalAlias*>::iterator 1653 iter = TypedSelectors.begin(), iterEnd = TypedSelectors.end(); 1654 iter != iterEnd ; ++iter) { 1655 Elements.push_back(ExportUniqueString(iter->first.first, ".objc_sel_name")); 1656 Elements.push_back(MakeConstantString(iter->first.second, 1657 ".objc_sel_types")); 1658 Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements)); 1659 Elements.clear(); 1660 } 1661 for (llvm::StringMap<llvm::GlobalAlias*>::iterator 1662 iter = UntypedSelectors.begin(), iterEnd = UntypedSelectors.end(); 1663 iter != iterEnd; ++iter) { 1664 Elements.push_back( 1665 ExportUniqueString(iter->getKeyData(), ".objc_sel_name")); 1666 Elements.push_back(NULLPtr); 1667 Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements)); 1668 Elements.clear(); 1669 } 1670 Elements.push_back(NULLPtr); 1671 Elements.push_back(NULLPtr); 1672 Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements)); 1673 Elements.clear(); 1674 // Number of static selectors 1675 Elements.push_back(llvm::ConstantInt::get(LongTy, Selectors.size() )); 1676 llvm::Constant *SelectorList = MakeGlobal( 1677 llvm::ArrayType::get(SelStructTy, Selectors.size()), Selectors, 1678 ".objc_selector_list"); 1679 Elements.push_back(llvm::ConstantExpr::getBitCast(SelectorList, 1680 SelStructPtrTy)); 1681 1682 // Now that all of the static selectors exist, create pointers to them. 1683 int index = 0; 1684 for (std::map<TypedSelector, llvm::GlobalAlias*>::iterator 1685 iter=TypedSelectors.begin(), iterEnd =TypedSelectors.end(); 1686 iter != iterEnd; ++iter) { 1687 llvm::Constant *Idxs[] = {Zeros[0], 1688 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), index++), Zeros[0]}; 1689 llvm::Constant *SelPtr = new llvm::GlobalVariable(TheModule, SelStructPtrTy, 1690 true, llvm::GlobalValue::LinkOnceODRLinkage, 1691 llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2), 1692 MangleSelectorTypes(".objc_sel_ptr"+iter->first.first+"."+ 1693 iter->first.second)); 1694 // If selectors are defined as an opaque type, cast the pointer to this 1695 // type. 1696 if (isSelOpaque) { 1697 SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, 1698 llvm::PointerType::getUnqual(SelectorTy)); 1699 } 1700 (*iter).second->replaceAllUsesWith(SelPtr); 1701 (*iter).second->eraseFromParent(); 1702 } 1703 for (llvm::StringMap<llvm::GlobalAlias*>::iterator 1704 iter=UntypedSelectors.begin(), iterEnd = UntypedSelectors.end(); 1705 iter != iterEnd; iter++) { 1706 llvm::Constant *Idxs[] = {Zeros[0], 1707 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), index++), Zeros[0]}; 1708 llvm::Constant *SelPtr = new llvm::GlobalVariable(TheModule, SelStructPtrTy, 1709 true, llvm::GlobalValue::LinkOnceODRLinkage, 1710 llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2), 1711 MangleSelectorTypes(std::string(".objc_sel_ptr")+iter->getKey().str())); 1712 // If selectors are defined as an opaque type, cast the pointer to this 1713 // type. 1714 if (isSelOpaque) { 1715 SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, 1716 llvm::PointerType::getUnqual(SelectorTy)); 1717 } 1718 (*iter).second->replaceAllUsesWith(SelPtr); 1719 (*iter).second->eraseFromParent(); 1720 } 1721 // Number of classes defined. 1722 Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext), 1723 Classes.size())); 1724 // Number of categories defined 1725 Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext), 1726 Categories.size())); 1727 // Create an array of classes, then categories, then static object instances 1728 Classes.insert(Classes.end(), Categories.begin(), Categories.end()); 1729 // NULL-terminated list of static object instances (mainly constant strings) 1730 Classes.push_back(Statics); 1731 Classes.push_back(NULLPtr); 1732 llvm::Constant *ClassList = llvm::ConstantArray::get(ClassListTy, Classes); 1733 Elements.push_back(ClassList); 1734 // Construct the symbol table 1735 llvm::Constant *SymTab= MakeGlobal(SymTabTy, Elements); 1736 1737 // The symbol table is contained in a module which has some version-checking 1738 // constants 1739 llvm::StructType * ModuleTy = llvm::StructType::get(VMContext, LongTy, LongTy, 1740 PtrToInt8Ty, llvm::PointerType::getUnqual(SymTabTy), NULL); 1741 Elements.clear(); 1742 // Runtime version used for compatibility checking. 1743 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) { 1744 Elements.push_back(llvm::ConstantInt::get(LongTy, 1745 NonFragileRuntimeVersion)); 1746 } else { 1747 Elements.push_back(llvm::ConstantInt::get(LongTy, RuntimeVersion)); 1748 } 1749 // sizeof(ModuleTy) 1750 llvm::TargetData td(&TheModule); 1751 Elements.push_back(llvm::ConstantInt::get(LongTy, 1752 td.getTypeSizeInBits(ModuleTy)/8)); 1753 //FIXME: Should be the path to the file where this module was declared 1754 Elements.push_back(NULLPtr); 1755 Elements.push_back(SymTab); 1756 llvm::Value *Module = MakeGlobal(ModuleTy, Elements); 1757 1758 // Create the load function calling the runtime entry point with the module 1759 // structure 1760 llvm::Function * LoadFunction = llvm::Function::Create( 1761 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false), 1762 llvm::GlobalValue::InternalLinkage, ".objc_load_function", 1763 &TheModule); 1764 llvm::BasicBlock *EntryBB = 1765 llvm::BasicBlock::Create(VMContext, "entry", LoadFunction); 1766 CGBuilderTy Builder(VMContext); 1767 Builder.SetInsertPoint(EntryBB); 1768 1769 std::vector<const llvm::Type*> Params(1, 1770 llvm::PointerType::getUnqual(ModuleTy)); 1771 llvm::Value *Register = CGM.CreateRuntimeFunction(llvm::FunctionType::get( 1772 llvm::Type::getVoidTy(VMContext), Params, true), "__objc_exec_class"); 1773 Builder.CreateCall(Register, Module); 1774 Builder.CreateRetVoid(); 1775 1776 return LoadFunction; 1777} 1778 1779llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD, 1780 const ObjCContainerDecl *CD) { 1781 const ObjCCategoryImplDecl *OCD = 1782 dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext()); 1783 std::string CategoryName = OCD ? OCD->getNameAsString() : ""; 1784 std::string ClassName = CD->getName(); 1785 std::string MethodName = OMD->getSelector().getAsString(); 1786 bool isClassMethod = !OMD->isInstanceMethod(); 1787 1788 CodeGenTypes &Types = CGM.getTypes(); 1789 const llvm::FunctionType *MethodTy = 1790 Types.GetFunctionType(Types.getFunctionInfo(OMD), OMD->isVariadic()); 1791 std::string FunctionName = SymbolNameForMethod(ClassName, CategoryName, 1792 MethodName, isClassMethod); 1793 1794 llvm::Function *Method 1795 = llvm::Function::Create(MethodTy, 1796 llvm::GlobalValue::InternalLinkage, 1797 FunctionName, 1798 &TheModule); 1799 return Method; 1800} 1801 1802llvm::Function *CGObjCGNU::GetPropertyGetFunction() { 1803 std::vector<const llvm::Type*> Params; 1804 const llvm::Type *BoolTy = 1805 CGM.getTypes().ConvertType(CGM.getContext().BoolTy); 1806 Params.push_back(IdTy); 1807 Params.push_back(SelectorTy); 1808 Params.push_back(IntTy); 1809 Params.push_back(BoolTy); 1810 // void objc_getProperty (id, SEL, int, bool) 1811 const llvm::FunctionType *FTy = 1812 llvm::FunctionType::get(IdTy, Params, false); 1813 return cast<llvm::Function>(CGM.CreateRuntimeFunction(FTy, 1814 "objc_getProperty")); 1815} 1816 1817llvm::Function *CGObjCGNU::GetPropertySetFunction() { 1818 std::vector<const llvm::Type*> Params; 1819 const llvm::Type *BoolTy = 1820 CGM.getTypes().ConvertType(CGM.getContext().BoolTy); 1821 Params.push_back(IdTy); 1822 Params.push_back(SelectorTy); 1823 Params.push_back(IntTy); 1824 Params.push_back(IdTy); 1825 Params.push_back(BoolTy); 1826 Params.push_back(BoolTy); 1827 // void objc_setProperty (id, SEL, int, id, bool, bool) 1828 const llvm::FunctionType *FTy = 1829 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Params, false); 1830 return cast<llvm::Function>(CGM.CreateRuntimeFunction(FTy, 1831 "objc_setProperty")); 1832} 1833 1834// FIXME. Implement this. 1835llvm::Function *CGObjCGNU::GetCopyStructFunction() { 1836 return 0; 1837} 1838 1839llvm::Constant *CGObjCGNU::EnumerationMutationFunction() { 1840 CodeGen::CodeGenTypes &Types = CGM.getTypes(); 1841 ASTContext &Ctx = CGM.getContext(); 1842 // void objc_enumerationMutation (id) 1843 llvm::SmallVector<CanQualType,1> Params; 1844 Params.push_back(ASTIdTy); 1845 const llvm::FunctionType *FTy = 1846 Types.GetFunctionType(Types.getFunctionInfo(Ctx.VoidTy, Params, 1847 FunctionType::ExtInfo()), false); 1848 return CGM.CreateRuntimeFunction(FTy, "objc_enumerationMutation"); 1849} 1850 1851void CGObjCGNU::EmitTryOrSynchronizedStmt(CodeGen::CodeGenFunction &CGF, 1852 const Stmt &S) { 1853 // Pointer to the personality function 1854 llvm::Constant *Personality = 1855 CGM.CreateRuntimeFunction(llvm::FunctionType::get(llvm::Type::getInt32Ty(VMContext), 1856 true), 1857 "__gnu_objc_personality_v0"); 1858 Personality = llvm::ConstantExpr::getBitCast(Personality, PtrTy); 1859 std::vector<const llvm::Type*> Params; 1860 Params.push_back(PtrTy); 1861 llvm::Value *RethrowFn = 1862 CGM.CreateRuntimeFunction(llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 1863 Params, false), "_Unwind_Resume"); 1864 1865 bool isTry = isa<ObjCAtTryStmt>(S); 1866 llvm::BasicBlock *TryBlock = CGF.createBasicBlock("try"); 1867 llvm::BasicBlock *PrevLandingPad = CGF.getInvokeDest(); 1868 llvm::BasicBlock *TryHandler = CGF.createBasicBlock("try.handler"); 1869 llvm::BasicBlock *CatchInCatch = CGF.createBasicBlock("catch.rethrow"); 1870 llvm::BasicBlock *FinallyBlock = CGF.createBasicBlock("finally"); 1871 llvm::BasicBlock *FinallyRethrow = CGF.createBasicBlock("finally.throw"); 1872 llvm::BasicBlock *FinallyEnd = CGF.createBasicBlock("finally.end"); 1873 1874 // @synchronized() 1875 if (!isTry) { 1876 std::vector<const llvm::Type*> Args(1, IdTy); 1877 llvm::FunctionType *FTy = 1878 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Args, false); 1879 llvm::Value *SyncEnter = CGM.CreateRuntimeFunction(FTy, "objc_sync_enter"); 1880 llvm::Value *SyncArg = 1881 CGF.EmitScalarExpr(cast<ObjCAtSynchronizedStmt>(S).getSynchExpr()); 1882 SyncArg = CGF.Builder.CreateBitCast(SyncArg, IdTy); 1883 CGF.Builder.CreateCall(SyncEnter, SyncArg); 1884 } 1885 1886 1887 // Push an EH context entry, used for handling rethrows and jumps 1888 // through finally. 1889 CGF.PushCleanupBlock(FinallyBlock); 1890 1891 // Emit the statements in the @try {} block 1892 CGF.setInvokeDest(TryHandler); 1893 1894 CGF.EmitBlock(TryBlock); 1895 CGF.EmitStmt(isTry ? cast<ObjCAtTryStmt>(S).getTryBody() 1896 : cast<ObjCAtSynchronizedStmt>(S).getSynchBody()); 1897 1898 // Jump to @finally if there is no exception 1899 CGF.EmitBranchThroughCleanup(FinallyEnd); 1900 1901 // Emit the handlers 1902 CGF.EmitBlock(TryHandler); 1903 1904 // Get the correct versions of the exception handling intrinsics 1905 llvm::Value *llvm_eh_exception = 1906 CGF.CGM.getIntrinsic(llvm::Intrinsic::eh_exception); 1907 llvm::Value *llvm_eh_selector = 1908 CGF.CGM.getIntrinsic(llvm::Intrinsic::eh_selector); 1909 llvm::Value *llvm_eh_typeid_for = 1910 CGF.CGM.getIntrinsic(llvm::Intrinsic::eh_typeid_for); 1911 1912 // Exception object 1913 llvm::Value *Exc = CGF.Builder.CreateCall(llvm_eh_exception, "exc"); 1914 llvm::Value *RethrowPtr = CGF.CreateTempAlloca(Exc->getType(), "_rethrow"); 1915 1916 llvm::SmallVector<llvm::Value*, 8> ESelArgs; 1917 llvm::SmallVector<std::pair<const VarDecl*, const Stmt*>, 8> Handlers; 1918 1919 ESelArgs.push_back(Exc); 1920 ESelArgs.push_back(Personality); 1921 1922 bool HasCatchAll = false; 1923 // Only @try blocks are allowed @catch blocks, but both can have @finally 1924 if (isTry) { 1925 if (cast<ObjCAtTryStmt>(S).getNumCatchStmts()) { 1926 const ObjCAtTryStmt &AtTry = cast<ObjCAtTryStmt>(S); 1927 CGF.setInvokeDest(CatchInCatch); 1928 1929 for (unsigned I = 0, N = AtTry.getNumCatchStmts(); I != N; ++I) { 1930 const ObjCAtCatchStmt *CatchStmt = AtTry.getCatchStmt(I); 1931 const VarDecl *CatchDecl = CatchStmt->getCatchParamDecl(); 1932 Handlers.push_back(std::make_pair(CatchDecl, 1933 CatchStmt->getCatchBody())); 1934 1935 // @catch() and @catch(id) both catch any ObjC exception 1936 if (!CatchDecl || CatchDecl->getType()->isObjCIdType() 1937 || CatchDecl->getType()->isObjCQualifiedIdType()) { 1938 // Use i8* null here to signal this is a catch all, not a cleanup. 1939 ESelArgs.push_back(NULLPtr); 1940 HasCatchAll = true; 1941 // No further catches after this one will ever by reached 1942 break; 1943 } 1944 1945 // All other types should be Objective-C interface pointer types. 1946 const ObjCObjectPointerType *OPT = 1947 CatchDecl->getType()->getAs<ObjCObjectPointerType>(); 1948 assert(OPT && "Invalid @catch type."); 1949 const ObjCInterfaceDecl *IDecl = 1950 OPT->getObjectType()->getInterface(); 1951 assert(IDecl && "Invalid @catch type."); 1952 llvm::Value *EHType = 1953 MakeConstantString(IDecl->getNameAsString()); 1954 ESelArgs.push_back(EHType); 1955 } 1956 } 1957 } 1958 1959 // We use a cleanup unless there was already a catch all. 1960 if (!HasCatchAll) { 1961 ESelArgs.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0)); 1962 Handlers.push_back(std::make_pair((const ParmVarDecl*) 0, (const Stmt*) 0)); 1963 } 1964 1965 // Find which handler was matched. 1966 llvm::Value *ESelector = CGF.Builder.CreateCall(llvm_eh_selector, 1967 ESelArgs.begin(), ESelArgs.end(), "selector"); 1968 1969 for (unsigned i = 0, e = Handlers.size(); i != e; ++i) { 1970 const VarDecl *CatchParam = Handlers[i].first; 1971 const Stmt *CatchBody = Handlers[i].second; 1972 1973 llvm::BasicBlock *Next = 0; 1974 1975 // The last handler always matches. 1976 if (i + 1 != e) { 1977 assert(CatchParam && "Only last handler can be a catch all."); 1978 1979 // Test whether this block matches the type for the selector and branch 1980 // to Match if it does, or to the next BB if it doesn't. 1981 llvm::BasicBlock *Match = CGF.createBasicBlock("match"); 1982 Next = CGF.createBasicBlock("catch.next"); 1983 llvm::Value *Id = CGF.Builder.CreateCall(llvm_eh_typeid_for, 1984 CGF.Builder.CreateBitCast(ESelArgs[i+2], PtrTy)); 1985 CGF.Builder.CreateCondBr(CGF.Builder.CreateICmpEQ(ESelector, Id), Match, 1986 Next); 1987 1988 CGF.EmitBlock(Match); 1989 } 1990 1991 if (CatchBody) { 1992 llvm::Value *ExcObject = CGF.Builder.CreateBitCast(Exc, 1993 CGF.ConvertType(CatchParam->getType())); 1994 1995 // Bind the catch parameter if it exists. 1996 if (CatchParam) { 1997 // CatchParam is a ParmVarDecl because of the grammar 1998 // construction used to handle this, but for codegen purposes 1999 // we treat this as a local decl. 2000 CGF.EmitLocalBlockVarDecl(*CatchParam); 2001 CGF.Builder.CreateStore(ExcObject, CGF.GetAddrOfLocalVar(CatchParam)); 2002 } 2003 2004 CGF.ObjCEHValueStack.push_back(ExcObject); 2005 CGF.EmitStmt(CatchBody); 2006 CGF.ObjCEHValueStack.pop_back(); 2007 2008 CGF.EmitBranchThroughCleanup(FinallyEnd); 2009 2010 if (Next) 2011 CGF.EmitBlock(Next); 2012 } else { 2013 assert(!Next && "catchup should be last handler."); 2014 2015 CGF.Builder.CreateStore(Exc, RethrowPtr); 2016 CGF.EmitBranchThroughCleanup(FinallyRethrow); 2017 } 2018 } 2019 // The @finally block is a secondary landing pad for any exceptions thrown in 2020 // @catch() blocks 2021 CGF.EmitBlock(CatchInCatch); 2022 Exc = CGF.Builder.CreateCall(llvm_eh_exception, "exc"); 2023 ESelArgs.clear(); 2024 ESelArgs.push_back(Exc); 2025 ESelArgs.push_back(Personality); 2026 // If there is a @catch or @finally clause in outside of this one then we 2027 // need to make sure that we catch and rethrow it. 2028 if (PrevLandingPad) { 2029 ESelArgs.push_back(NULLPtr); 2030 } else { 2031 ESelArgs.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0)); 2032 } 2033 CGF.Builder.CreateCall(llvm_eh_selector, ESelArgs.begin(), ESelArgs.end(), 2034 "selector"); 2035 CGF.Builder.CreateCall(llvm_eh_typeid_for, 2036 CGF.Builder.CreateIntToPtr(ESelArgs[2], PtrTy)); 2037 CGF.Builder.CreateStore(Exc, RethrowPtr); 2038 CGF.EmitBranchThroughCleanup(FinallyRethrow); 2039 2040 CodeGenFunction::CleanupBlockInfo Info = CGF.PopCleanupBlock(); 2041 2042 CGF.setInvokeDest(PrevLandingPad); 2043 2044 CGF.EmitBlock(FinallyBlock); 2045 2046 2047 if (isTry) { 2048 if (const ObjCAtFinallyStmt* FinallyStmt = 2049 cast<ObjCAtTryStmt>(S).getFinallyStmt()) 2050 CGF.EmitStmt(FinallyStmt->getFinallyBody()); 2051 } else { 2052 // Emit 'objc_sync_exit(expr)' as finally's sole statement for 2053 // @synchronized. 2054 std::vector<const llvm::Type*> Args(1, IdTy); 2055 llvm::FunctionType *FTy = 2056 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Args, false); 2057 llvm::Value *SyncExit = CGM.CreateRuntimeFunction(FTy, "objc_sync_exit"); 2058 llvm::Value *SyncArg = 2059 CGF.EmitScalarExpr(cast<ObjCAtSynchronizedStmt>(S).getSynchExpr()); 2060 SyncArg = CGF.Builder.CreateBitCast(SyncArg, IdTy); 2061 CGF.Builder.CreateCall(SyncExit, SyncArg); 2062 } 2063 2064 if (Info.SwitchBlock) 2065 CGF.EmitBlock(Info.SwitchBlock); 2066 if (Info.EndBlock) 2067 CGF.EmitBlock(Info.EndBlock); 2068 2069 // Branch around the rethrow code. 2070 CGF.EmitBranch(FinallyEnd); 2071 2072 CGF.EmitBlock(FinallyRethrow); 2073 2074 llvm::Value *ExceptionObject = CGF.Builder.CreateLoad(RethrowPtr); 2075 llvm::BasicBlock *UnwindBB = CGF.getInvokeDest(); 2076 if (!UnwindBB) { 2077 CGF.Builder.CreateCall(RethrowFn, ExceptionObject); 2078 // Exception always thrown, next instruction is never reached. 2079 CGF.Builder.CreateUnreachable(); 2080 } else { 2081 // If there is a @catch block outside this scope, we invoke instead of 2082 // calling because we may return to this function. This is very slow, but 2083 // some people still do it. It would be nice to add an optimised path for 2084 // this. 2085 CGF.Builder.CreateInvoke(RethrowFn, UnwindBB, UnwindBB, &ExceptionObject, 2086 &ExceptionObject+1); 2087 } 2088 2089 CGF.EmitBlock(FinallyEnd); 2090} 2091 2092void CGObjCGNU::EmitThrowStmt(CodeGen::CodeGenFunction &CGF, 2093 const ObjCAtThrowStmt &S) { 2094 llvm::Value *ExceptionAsObject; 2095 2096 std::vector<const llvm::Type*> Args(1, IdTy); 2097 llvm::FunctionType *FTy = 2098 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Args, false); 2099 llvm::Value *ThrowFn = 2100 CGM.CreateRuntimeFunction(FTy, "objc_exception_throw"); 2101 2102 if (const Expr *ThrowExpr = S.getThrowExpr()) { 2103 llvm::Value *Exception = CGF.EmitScalarExpr(ThrowExpr); 2104 ExceptionAsObject = Exception; 2105 } else { 2106 assert((!CGF.ObjCEHValueStack.empty() && CGF.ObjCEHValueStack.back()) && 2107 "Unexpected rethrow outside @catch block."); 2108 ExceptionAsObject = CGF.ObjCEHValueStack.back(); 2109 } 2110 ExceptionAsObject = 2111 CGF.Builder.CreateBitCast(ExceptionAsObject, IdTy, "tmp"); 2112 2113 // Note: This may have to be an invoke, if we want to support constructs like: 2114 // @try { 2115 // @throw(obj); 2116 // } 2117 // @catch(id) ... 2118 // 2119 // This is effectively turning @throw into an incredibly-expensive goto, but 2120 // it may happen as a result of inlining followed by missed optimizations, or 2121 // as a result of stupidity. 2122 llvm::BasicBlock *UnwindBB = CGF.getInvokeDest(); 2123 if (!UnwindBB) { 2124 CGF.Builder.CreateCall(ThrowFn, ExceptionAsObject); 2125 CGF.Builder.CreateUnreachable(); 2126 } else { 2127 CGF.Builder.CreateInvoke(ThrowFn, UnwindBB, UnwindBB, &ExceptionAsObject, 2128 &ExceptionAsObject+1); 2129 } 2130 // Clear the insertion point to indicate we are in unreachable code. 2131 CGF.Builder.ClearInsertionPoint(); 2132} 2133 2134llvm::Value * CGObjCGNU::EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF, 2135 llvm::Value *AddrWeakObj) { 2136 CGBuilderTy B = CGF.Builder; 2137 AddrWeakObj = EnforceType(B, AddrWeakObj, IdTy); 2138 return B.CreateCall(WeakReadFn, AddrWeakObj); 2139} 2140 2141void CGObjCGNU::EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF, 2142 llvm::Value *src, llvm::Value *dst) { 2143 CGBuilderTy B = CGF.Builder; 2144 src = EnforceType(B, src, IdTy); 2145 dst = EnforceType(B, dst, PtrToIdTy); 2146 B.CreateCall2(WeakAssignFn, src, dst); 2147} 2148 2149void CGObjCGNU::EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF, 2150 llvm::Value *src, llvm::Value *dst) { 2151 CGBuilderTy B = CGF.Builder; 2152 src = EnforceType(B, src, IdTy); 2153 dst = EnforceType(B, dst, PtrToIdTy); 2154 B.CreateCall2(GlobalAssignFn, src, dst); 2155} 2156 2157void CGObjCGNU::EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF, 2158 llvm::Value *src, llvm::Value *dst, 2159 llvm::Value *ivarOffset) { 2160 CGBuilderTy B = CGF.Builder; 2161 src = EnforceType(B, src, IdTy); 2162 dst = EnforceType(B, dst, PtrToIdTy); 2163 B.CreateCall3(IvarAssignFn, src, dst, ivarOffset); 2164} 2165 2166void CGObjCGNU::EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF, 2167 llvm::Value *src, llvm::Value *dst) { 2168 CGBuilderTy B = CGF.Builder; 2169 src = EnforceType(B, src, IdTy); 2170 dst = EnforceType(B, dst, PtrToIdTy); 2171 B.CreateCall2(StrongCastAssignFn, src, dst); 2172} 2173 2174void CGObjCGNU::EmitGCMemmoveCollectable(CodeGen::CodeGenFunction &CGF, 2175 llvm::Value *DestPtr, 2176 llvm::Value *SrcPtr, 2177 QualType Ty) { 2178 CGBuilderTy B = CGF.Builder; 2179 DestPtr = EnforceType(B, DestPtr, IdTy); 2180 SrcPtr = EnforceType(B, SrcPtr, PtrToIdTy); 2181 2182 std::pair<uint64_t, unsigned> TypeInfo = CGM.getContext().getTypeInfo(Ty); 2183 unsigned long size = TypeInfo.first/8; 2184 // FIXME: size_t 2185 llvm::Value *N = llvm::ConstantInt::get(LongTy, size); 2186 2187 B.CreateCall3(MemMoveFn, DestPtr, SrcPtr, N); 2188} 2189 2190llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable( 2191 const ObjCInterfaceDecl *ID, 2192 const ObjCIvarDecl *Ivar) { 2193 const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString() 2194 + '.' + Ivar->getNameAsString(); 2195 // Emit the variable and initialize it with what we think the correct value 2196 // is. This allows code compiled with non-fragile ivars to work correctly 2197 // when linked against code which isn't (most of the time). 2198 llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name); 2199 if (!IvarOffsetPointer) { 2200 uint64_t Offset; 2201 if (ObjCImplementationDecl *OID = 2202 CGM.getContext().getObjCImplementation( 2203 const_cast<ObjCInterfaceDecl *>(ID))) 2204 Offset = ComputeIvarBaseOffset(CGM, OID, Ivar); 2205 else 2206 Offset = ComputeIvarBaseOffset(CGM, ID, Ivar); 2207 2208 llvm::ConstantInt *OffsetGuess = 2209 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Offset, "ivar"); 2210 // Don't emit the guess in non-PIC code because the linker will not be able 2211 // to replace it with the real version for a library. In non-PIC code you 2212 // must compile with the fragile ABI if you want to use ivars from a 2213 // GCC-compiled class. 2214 if (CGM.getLangOptions().PICLevel) { 2215 llvm::GlobalVariable *IvarOffsetGV = new llvm::GlobalVariable(TheModule, 2216 llvm::Type::getInt32Ty(VMContext), false, 2217 llvm::GlobalValue::PrivateLinkage, OffsetGuess, Name+".guess"); 2218 IvarOffsetPointer = new llvm::GlobalVariable(TheModule, 2219 IvarOffsetGV->getType(), false, llvm::GlobalValue::LinkOnceAnyLinkage, 2220 IvarOffsetGV, Name); 2221 } else { 2222 IvarOffsetPointer = new llvm::GlobalVariable(TheModule, 2223 llvm::Type::getInt32PtrTy(VMContext), false, 2224 llvm::GlobalValue::ExternalLinkage, 0, Name); 2225 } 2226 } 2227 return IvarOffsetPointer; 2228} 2229 2230LValue CGObjCGNU::EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF, 2231 QualType ObjectTy, 2232 llvm::Value *BaseValue, 2233 const ObjCIvarDecl *Ivar, 2234 unsigned CVRQualifiers) { 2235 const ObjCInterfaceDecl *ID = 2236 ObjectTy->getAs<ObjCObjectType>()->getInterface(); 2237 return EmitValueForIvarAtOffset(CGF, ID, BaseValue, Ivar, CVRQualifiers, 2238 EmitIvarOffset(CGF, ID, Ivar)); 2239} 2240 2241static const ObjCInterfaceDecl *FindIvarInterface(ASTContext &Context, 2242 const ObjCInterfaceDecl *OID, 2243 const ObjCIvarDecl *OIVD) { 2244 llvm::SmallVector<ObjCIvarDecl*, 16> Ivars; 2245 Context.ShallowCollectObjCIvars(OID, Ivars); 2246 for (unsigned k = 0, e = Ivars.size(); k != e; ++k) { 2247 if (OIVD == Ivars[k]) 2248 return OID; 2249 } 2250 2251 // Otherwise check in the super class. 2252 if (const ObjCInterfaceDecl *Super = OID->getSuperClass()) 2253 return FindIvarInterface(Context, Super, OIVD); 2254 2255 return 0; 2256} 2257 2258llvm::Value *CGObjCGNU::EmitIvarOffset(CodeGen::CodeGenFunction &CGF, 2259 const ObjCInterfaceDecl *Interface, 2260 const ObjCIvarDecl *Ivar) { 2261 if (CGM.getLangOptions().ObjCNonFragileABI) { 2262 Interface = FindIvarInterface(CGM.getContext(), Interface, Ivar); 2263 return CGF.Builder.CreateLoad(CGF.Builder.CreateLoad( 2264 ObjCIvarOffsetVariable(Interface, Ivar), false, "ivar")); 2265 } 2266 uint64_t Offset = ComputeIvarBaseOffset(CGF.CGM, Interface, Ivar); 2267 return llvm::ConstantInt::get(LongTy, Offset, "ivar"); 2268} 2269 2270CodeGen::CGObjCRuntime * 2271CodeGen::CreateGNUObjCRuntime(CodeGen::CodeGenModule &CGM) { 2272 return new CGObjCGNU(CGM); 2273} 2274