CGObjC.cpp revision 410ffb2bc5f072d58a73c14560345bcf77dec1cc
1//===---- CGBuiltin.cpp - Emit LLVM Code for builtins ---------------------===// 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 contains code to emit Objective-C code as LLVM code. 11// 12//===----------------------------------------------------------------------===// 13 14#include "CGDebugInfo.h" 15#include "CGObjCRuntime.h" 16#include "CodeGenFunction.h" 17#include "CodeGenModule.h" 18#include "TargetInfo.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/StmtObjC.h" 22#include "clang/Basic/Diagnostic.h" 23#include "llvm/ADT/STLExtras.h" 24#include "llvm/Target/TargetData.h" 25#include "llvm/InlineAsm.h" 26using namespace clang; 27using namespace CodeGen; 28 29typedef llvm::PointerIntPair<llvm::Value*,1,bool> TryEmitResult; 30static TryEmitResult 31tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e); 32 33/// Given the address of a variable of pointer type, find the correct 34/// null to store into it. 35static llvm::Constant *getNullForVariable(llvm::Value *addr) { 36 llvm::Type *type = 37 cast<llvm::PointerType>(addr->getType())->getElementType(); 38 return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(type)); 39} 40 41/// Emits an instance of NSConstantString representing the object. 42llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E) 43{ 44 llvm::Constant *C = 45 CGM.getObjCRuntime().GenerateConstantString(E->getString()); 46 // FIXME: This bitcast should just be made an invariant on the Runtime. 47 return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType())); 48} 49 50/// Emit a selector. 51llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) { 52 // Untyped selector. 53 // Note that this implementation allows for non-constant strings to be passed 54 // as arguments to @selector(). Currently, the only thing preventing this 55 // behaviour is the type checking in the front end. 56 return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector()); 57} 58 59llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) { 60 // FIXME: This should pass the Decl not the name. 61 return CGM.getObjCRuntime().GenerateProtocolRef(Builder, E->getProtocol()); 62} 63 64/// \brief Adjust the type of the result of an Objective-C message send 65/// expression when the method has a related result type. 66static RValue AdjustRelatedResultType(CodeGenFunction &CGF, 67 const Expr *E, 68 const ObjCMethodDecl *Method, 69 RValue Result) { 70 if (!Method) 71 return Result; 72 73 if (!Method->hasRelatedResultType() || 74 CGF.getContext().hasSameType(E->getType(), Method->getResultType()) || 75 !Result.isScalar()) 76 return Result; 77 78 // We have applied a related result type. Cast the rvalue appropriately. 79 return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(), 80 CGF.ConvertType(E->getType()))); 81} 82 83/// Decide whether to extend the lifetime of the receiver of a 84/// returns-inner-pointer message. 85static bool 86shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) { 87 switch (message->getReceiverKind()) { 88 89 // For a normal instance message, we should extend unless the 90 // receiver is loaded from a variable with precise lifetime. 91 case ObjCMessageExpr::Instance: { 92 const Expr *receiver = message->getInstanceReceiver(); 93 const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver); 94 if (!ice || ice->getCastKind() != CK_LValueToRValue) return true; 95 receiver = ice->getSubExpr()->IgnoreParens(); 96 97 // Only __strong variables. 98 if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong) 99 return true; 100 101 // All ivars and fields have precise lifetime. 102 if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver)) 103 return false; 104 105 // Otherwise, check for variables. 106 const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr()); 107 if (!declRef) return true; 108 const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl()); 109 if (!var) return true; 110 111 // All variables have precise lifetime except local variables with 112 // automatic storage duration that aren't specially marked. 113 return (var->hasLocalStorage() && 114 !var->hasAttr<ObjCPreciseLifetimeAttr>()); 115 } 116 117 case ObjCMessageExpr::Class: 118 case ObjCMessageExpr::SuperClass: 119 // It's never necessary for class objects. 120 return false; 121 122 case ObjCMessageExpr::SuperInstance: 123 // We generally assume that 'self' lives throughout a method call. 124 return false; 125 } 126 127 llvm_unreachable("invalid receiver kind"); 128} 129 130RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E, 131 ReturnValueSlot Return) { 132 // Only the lookup mechanism and first two arguments of the method 133 // implementation vary between runtimes. We can get the receiver and 134 // arguments in generic code. 135 136 bool isDelegateInit = E->isDelegateInitCall(); 137 138 const ObjCMethodDecl *method = E->getMethodDecl(); 139 140 // We don't retain the receiver in delegate init calls, and this is 141 // safe because the receiver value is always loaded from 'self', 142 // which we zero out. We don't want to Block_copy block receivers, 143 // though. 144 bool retainSelf = 145 (!isDelegateInit && 146 CGM.getLangOptions().ObjCAutoRefCount && 147 method && 148 method->hasAttr<NSConsumesSelfAttr>()); 149 150 CGObjCRuntime &Runtime = CGM.getObjCRuntime(); 151 bool isSuperMessage = false; 152 bool isClassMessage = false; 153 ObjCInterfaceDecl *OID = 0; 154 // Find the receiver 155 QualType ReceiverType; 156 llvm::Value *Receiver = 0; 157 switch (E->getReceiverKind()) { 158 case ObjCMessageExpr::Instance: 159 ReceiverType = E->getInstanceReceiver()->getType(); 160 if (retainSelf) { 161 TryEmitResult ter = tryEmitARCRetainScalarExpr(*this, 162 E->getInstanceReceiver()); 163 Receiver = ter.getPointer(); 164 if (ter.getInt()) retainSelf = false; 165 } else 166 Receiver = EmitScalarExpr(E->getInstanceReceiver()); 167 break; 168 169 case ObjCMessageExpr::Class: { 170 ReceiverType = E->getClassReceiver(); 171 const ObjCObjectType *ObjTy = ReceiverType->getAs<ObjCObjectType>(); 172 assert(ObjTy && "Invalid Objective-C class message send"); 173 OID = ObjTy->getInterface(); 174 assert(OID && "Invalid Objective-C class message send"); 175 Receiver = Runtime.GetClass(Builder, OID); 176 isClassMessage = true; 177 break; 178 } 179 180 case ObjCMessageExpr::SuperInstance: 181 ReceiverType = E->getSuperType(); 182 Receiver = LoadObjCSelf(); 183 isSuperMessage = true; 184 break; 185 186 case ObjCMessageExpr::SuperClass: 187 ReceiverType = E->getSuperType(); 188 Receiver = LoadObjCSelf(); 189 isSuperMessage = true; 190 isClassMessage = true; 191 break; 192 } 193 194 if (retainSelf) 195 Receiver = EmitARCRetainNonBlock(Receiver); 196 197 // In ARC, we sometimes want to "extend the lifetime" 198 // (i.e. retain+autorelease) of receivers of returns-inner-pointer 199 // messages. 200 if (getLangOptions().ObjCAutoRefCount && method && 201 method->hasAttr<ObjCReturnsInnerPointerAttr>() && 202 shouldExtendReceiverForInnerPointerMessage(E)) 203 Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver); 204 205 QualType ResultType = 206 method ? method->getResultType() : E->getType(); 207 208 CallArgList Args; 209 EmitCallArgs(Args, method, E->arg_begin(), E->arg_end()); 210 211 // For delegate init calls in ARC, do an unsafe store of null into 212 // self. This represents the call taking direct ownership of that 213 // value. We have to do this after emitting the other call 214 // arguments because they might also reference self, but we don't 215 // have to worry about any of them modifying self because that would 216 // be an undefined read and write of an object in unordered 217 // expressions. 218 if (isDelegateInit) { 219 assert(getLangOptions().ObjCAutoRefCount && 220 "delegate init calls should only be marked in ARC"); 221 222 // Do an unsafe store of null into self. 223 llvm::Value *selfAddr = 224 LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()]; 225 assert(selfAddr && "no self entry for a delegate init call?"); 226 227 Builder.CreateStore(getNullForVariable(selfAddr), selfAddr); 228 } 229 230 RValue result; 231 if (isSuperMessage) { 232 // super is only valid in an Objective-C method 233 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl); 234 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext()); 235 result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType, 236 E->getSelector(), 237 OMD->getClassInterface(), 238 isCategoryImpl, 239 Receiver, 240 isClassMessage, 241 Args, 242 method); 243 } else { 244 result = Runtime.GenerateMessageSend(*this, Return, ResultType, 245 E->getSelector(), 246 Receiver, Args, OID, 247 method); 248 } 249 250 // For delegate init calls in ARC, implicitly store the result of 251 // the call back into self. This takes ownership of the value. 252 if (isDelegateInit) { 253 llvm::Value *selfAddr = 254 LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()]; 255 llvm::Value *newSelf = result.getScalarVal(); 256 257 // The delegate return type isn't necessarily a matching type; in 258 // fact, it's quite likely to be 'id'. 259 llvm::Type *selfTy = 260 cast<llvm::PointerType>(selfAddr->getType())->getElementType(); 261 newSelf = Builder.CreateBitCast(newSelf, selfTy); 262 263 Builder.CreateStore(newSelf, selfAddr); 264 } 265 266 return AdjustRelatedResultType(*this, E, method, result); 267} 268 269namespace { 270struct FinishARCDealloc : EHScopeStack::Cleanup { 271 void Emit(CodeGenFunction &CGF, Flags flags) { 272 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl); 273 274 const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext()); 275 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 276 if (!iface->getSuperClass()) return; 277 278 bool isCategory = isa<ObjCCategoryImplDecl>(impl); 279 280 // Call [super dealloc] if we have a superclass. 281 llvm::Value *self = CGF.LoadObjCSelf(); 282 283 CallArgList args; 284 CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(), 285 CGF.getContext().VoidTy, 286 method->getSelector(), 287 iface, 288 isCategory, 289 self, 290 /*is class msg*/ false, 291 args, 292 method); 293 } 294}; 295} 296 297/// StartObjCMethod - Begin emission of an ObjCMethod. This generates 298/// the LLVM function and sets the other context used by 299/// CodeGenFunction. 300void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD, 301 const ObjCContainerDecl *CD, 302 SourceLocation StartLoc) { 303 FunctionArgList args; 304 // Check if we should generate debug info for this method. 305 if (CGM.getModuleDebugInfo() && !OMD->hasAttr<NoDebugAttr>()) 306 DebugInfo = CGM.getModuleDebugInfo(); 307 308 llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD); 309 310 const CGFunctionInfo &FI = CGM.getTypes().getFunctionInfo(OMD); 311 CGM.SetInternalFunctionAttributes(OMD, Fn, FI); 312 313 args.push_back(OMD->getSelfDecl()); 314 args.push_back(OMD->getCmdDecl()); 315 316 for (ObjCMethodDecl::param_iterator PI = OMD->param_begin(), 317 E = OMD->param_end(); PI != E; ++PI) 318 args.push_back(*PI); 319 320 CurGD = OMD; 321 322 StartFunction(OMD, OMD->getResultType(), Fn, FI, args, StartLoc); 323 324 // In ARC, certain methods get an extra cleanup. 325 if (CGM.getLangOptions().ObjCAutoRefCount && 326 OMD->isInstanceMethod() && 327 OMD->getSelector().isUnarySelector()) { 328 const IdentifierInfo *ident = 329 OMD->getSelector().getIdentifierInfoForSlot(0); 330 if (ident->isStr("dealloc")) 331 EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind()); 332 } 333} 334 335static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF, 336 LValue lvalue, QualType type); 337 338void CodeGenFunction::GenerateObjCGetterBody(ObjCIvarDecl *Ivar, 339 bool IsAtomic, bool IsStrong) { 340 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 341 Ivar, 0); 342 llvm::Value *GetCopyStructFn = 343 CGM.getObjCRuntime().GetGetStructFunction(); 344 CodeGenTypes &Types = CGM.getTypes(); 345 // objc_copyStruct (ReturnValue, &structIvar, 346 // sizeof (Type of Ivar), isAtomic, false); 347 CallArgList Args; 348 RValue RV = RValue::get(Builder.CreateBitCast(ReturnValue, VoidPtrTy)); 349 Args.add(RV, getContext().VoidPtrTy); 350 RV = RValue::get(Builder.CreateBitCast(LV.getAddress(), VoidPtrTy)); 351 Args.add(RV, getContext().VoidPtrTy); 352 // sizeof (Type of Ivar) 353 CharUnits Size = getContext().getTypeSizeInChars(Ivar->getType()); 354 llvm::Value *SizeVal = 355 llvm::ConstantInt::get(Types.ConvertType(getContext().LongTy), 356 Size.getQuantity()); 357 Args.add(RValue::get(SizeVal), getContext().LongTy); 358 llvm::Value *isAtomic = 359 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 360 IsAtomic ? 1 : 0); 361 Args.add(RValue::get(isAtomic), getContext().BoolTy); 362 llvm::Value *hasStrong = 363 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 364 IsStrong ? 1 : 0); 365 Args.add(RValue::get(hasStrong), getContext().BoolTy); 366 EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args, 367 FunctionType::ExtInfo()), 368 GetCopyStructFn, ReturnValueSlot(), Args); 369} 370 371/// Generate an Objective-C method. An Objective-C method is a C function with 372/// its pointer, name, and types registered in the class struture. 373void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) { 374 StartObjCMethod(OMD, OMD->getClassInterface(), OMD->getLocStart()); 375 EmitStmt(OMD->getBody()); 376 FinishFunction(OMD->getBodyRBrace()); 377} 378 379// FIXME: I wasn't sure about the synthesis approach. If we end up generating an 380// AST for the whole body we can just fall back to having a GenerateFunction 381// which takes the body Stmt. 382 383/// GenerateObjCGetter - Generate an Objective-C property getter 384/// function. The given Decl must be an ObjCImplementationDecl. @synthesize 385/// is illegal within a category. 386void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP, 387 const ObjCPropertyImplDecl *PID) { 388 ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl(); 389 const ObjCPropertyDecl *PD = PID->getPropertyDecl(); 390 bool IsAtomic = 391 !(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic); 392 ObjCMethodDecl *OMD = PD->getGetterMethodDecl(); 393 assert(OMD && "Invalid call to generate getter (empty method)"); 394 StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart()); 395 396 // Determine if we should use an objc_getProperty call for 397 // this. Non-atomic properties are directly evaluated. 398 // atomic 'copy' and 'retain' properties are also directly 399 // evaluated in gc-only mode. 400 if (CGM.getLangOptions().getGCMode() != LangOptions::GCOnly && 401 IsAtomic && 402 (PD->getSetterKind() == ObjCPropertyDecl::Copy || 403 PD->getSetterKind() == ObjCPropertyDecl::Retain)) { 404 llvm::Value *GetPropertyFn = 405 CGM.getObjCRuntime().GetPropertyGetFunction(); 406 407 if (!GetPropertyFn) { 408 CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy"); 409 FinishFunction(); 410 return; 411 } 412 413 // Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true). 414 // FIXME: Can't this be simpler? This might even be worse than the 415 // corresponding gcc code. 416 CodeGenTypes &Types = CGM.getTypes(); 417 ValueDecl *Cmd = OMD->getCmdDecl(); 418 llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd"); 419 QualType IdTy = getContext().getObjCIdType(); 420 llvm::Value *SelfAsId = 421 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy)); 422 llvm::Value *Offset = EmitIvarOffset(IMP->getClassInterface(), Ivar); 423 llvm::Value *True = 424 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1); 425 CallArgList Args; 426 Args.add(RValue::get(SelfAsId), IdTy); 427 Args.add(RValue::get(CmdVal), Cmd->getType()); 428 Args.add(RValue::get(Offset), getContext().getPointerDiffType()); 429 Args.add(RValue::get(True), getContext().BoolTy); 430 // FIXME: We shouldn't need to get the function info here, the 431 // runtime already should have computed it to build the function. 432 RValue RV = EmitCall(Types.getFunctionInfo(PD->getType(), Args, 433 FunctionType::ExtInfo()), 434 GetPropertyFn, ReturnValueSlot(), Args); 435 // We need to fix the type here. Ivars with copy & retain are 436 // always objects so we don't need to worry about complex or 437 // aggregates. 438 RV = RValue::get(Builder.CreateBitCast(RV.getScalarVal(), 439 Types.ConvertType(PD->getType()))); 440 EmitReturnOfRValue(RV, PD->getType()); 441 442 // objc_getProperty does an autorelease, so we should suppress ours. 443 AutoreleaseResult = false; 444 } else { 445 const llvm::Triple &Triple = getContext().Target.getTriple(); 446 QualType IVART = Ivar->getType(); 447 if (IsAtomic && 448 IVART->isScalarType() && 449 (Triple.getArch() == llvm::Triple::arm || 450 Triple.getArch() == llvm::Triple::thumb) && 451 (getContext().getTypeSizeInChars(IVART) 452 > CharUnits::fromQuantity(4)) && 453 CGM.getObjCRuntime().GetGetStructFunction()) { 454 GenerateObjCGetterBody(Ivar, true, false); 455 } 456 else if (IsAtomic && 457 (IVART->isScalarType() && !IVART->isRealFloatingType()) && 458 Triple.getArch() == llvm::Triple::x86 && 459 (getContext().getTypeSizeInChars(IVART) 460 > CharUnits::fromQuantity(4)) && 461 CGM.getObjCRuntime().GetGetStructFunction()) { 462 GenerateObjCGetterBody(Ivar, true, false); 463 } 464 else if (IsAtomic && 465 (IVART->isScalarType() && !IVART->isRealFloatingType()) && 466 Triple.getArch() == llvm::Triple::x86_64 && 467 (getContext().getTypeSizeInChars(IVART) 468 > CharUnits::fromQuantity(8)) && 469 CGM.getObjCRuntime().GetGetStructFunction()) { 470 GenerateObjCGetterBody(Ivar, true, false); 471 } 472 else if (IVART->isAnyComplexType()) { 473 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 474 Ivar, 0); 475 ComplexPairTy Pair = LoadComplexFromAddr(LV.getAddress(), 476 LV.isVolatileQualified()); 477 StoreComplexToAddr(Pair, ReturnValue, LV.isVolatileQualified()); 478 } 479 else if (hasAggregateLLVMType(IVART)) { 480 bool IsStrong = false; 481 if ((IsStrong = IvarTypeWithAggrGCObjects(IVART)) 482 && CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect 483 && CGM.getObjCRuntime().GetGetStructFunction()) { 484 GenerateObjCGetterBody(Ivar, IsAtomic, IsStrong); 485 } 486 else { 487 const CXXRecordDecl *classDecl = IVART->getAsCXXRecordDecl(); 488 489 if (PID->getGetterCXXConstructor() && 490 classDecl && !classDecl->hasTrivialDefaultConstructor()) { 491 ReturnStmt *Stmt = 492 new (getContext()) ReturnStmt(SourceLocation(), 493 PID->getGetterCXXConstructor(), 494 0); 495 EmitReturnStmt(*Stmt); 496 } else if (IsAtomic && 497 !IVART->isAnyComplexType() && 498 Triple.getArch() == llvm::Triple::x86 && 499 (getContext().getTypeSizeInChars(IVART) 500 > CharUnits::fromQuantity(4)) && 501 CGM.getObjCRuntime().GetGetStructFunction()) { 502 GenerateObjCGetterBody(Ivar, true, false); 503 } 504 else if (IsAtomic && 505 !IVART->isAnyComplexType() && 506 Triple.getArch() == llvm::Triple::x86_64 && 507 (getContext().getTypeSizeInChars(IVART) 508 > CharUnits::fromQuantity(8)) && 509 CGM.getObjCRuntime().GetGetStructFunction()) { 510 GenerateObjCGetterBody(Ivar, true, false); 511 } 512 else { 513 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 514 Ivar, 0); 515 EmitAggregateCopy(ReturnValue, LV.getAddress(), IVART); 516 } 517 } 518 } else { 519 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 520 Ivar, 0); 521 QualType propType = PD->getType(); 522 523 llvm::Value *value; 524 if (propType->isReferenceType()) { 525 value = LV.getAddress(); 526 } else { 527 // We want to load and autoreleaseReturnValue ARC __weak ivars. 528 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) { 529 value = emitARCRetainLoadOfScalar(*this, LV, IVART); 530 531 // Otherwise we want to do a simple load, suppressing the 532 // final autorelease. 533 } else { 534 value = EmitLoadOfLValue(LV).getScalarVal(); 535 AutoreleaseResult = false; 536 } 537 538 value = Builder.CreateBitCast(value, ConvertType(propType)); 539 } 540 541 EmitReturnOfRValue(RValue::get(value), propType); 542 } 543 } 544 545 FinishFunction(); 546} 547 548void CodeGenFunction::GenerateObjCAtomicSetterBody(ObjCMethodDecl *OMD, 549 ObjCIvarDecl *Ivar) { 550 // objc_copyStruct (&structIvar, &Arg, 551 // sizeof (struct something), true, false); 552 llvm::Value *GetCopyStructFn = 553 CGM.getObjCRuntime().GetSetStructFunction(); 554 CodeGenTypes &Types = CGM.getTypes(); 555 CallArgList Args; 556 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), Ivar, 0); 557 RValue RV = 558 RValue::get(Builder.CreateBitCast(LV.getAddress(), 559 Types.ConvertType(getContext().VoidPtrTy))); 560 Args.add(RV, getContext().VoidPtrTy); 561 llvm::Value *Arg = LocalDeclMap[*OMD->param_begin()]; 562 llvm::Value *ArgAsPtrTy = 563 Builder.CreateBitCast(Arg, 564 Types.ConvertType(getContext().VoidPtrTy)); 565 RV = RValue::get(ArgAsPtrTy); 566 Args.add(RV, getContext().VoidPtrTy); 567 // sizeof (Type of Ivar) 568 CharUnits Size = getContext().getTypeSizeInChars(Ivar->getType()); 569 llvm::Value *SizeVal = 570 llvm::ConstantInt::get(Types.ConvertType(getContext().LongTy), 571 Size.getQuantity()); 572 Args.add(RValue::get(SizeVal), getContext().LongTy); 573 llvm::Value *True = 574 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1); 575 Args.add(RValue::get(True), getContext().BoolTy); 576 llvm::Value *False = 577 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 0); 578 Args.add(RValue::get(False), getContext().BoolTy); 579 EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args, 580 FunctionType::ExtInfo()), 581 GetCopyStructFn, ReturnValueSlot(), Args); 582} 583 584static bool 585IvarAssignHasTrvialAssignment(const ObjCPropertyImplDecl *PID, 586 QualType IvarT) { 587 bool HasTrvialAssignment = true; 588 if (PID->getSetterCXXAssignment()) { 589 const CXXRecordDecl *classDecl = IvarT->getAsCXXRecordDecl(); 590 HasTrvialAssignment = 591 (!classDecl || classDecl->hasTrivialCopyAssignment()); 592 } 593 return HasTrvialAssignment; 594} 595 596/// GenerateObjCSetter - Generate an Objective-C property setter 597/// function. The given Decl must be an ObjCImplementationDecl. @synthesize 598/// is illegal within a category. 599void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP, 600 const ObjCPropertyImplDecl *PID) { 601 ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl(); 602 const ObjCPropertyDecl *PD = PID->getPropertyDecl(); 603 ObjCMethodDecl *OMD = PD->getSetterMethodDecl(); 604 assert(OMD && "Invalid call to generate setter (empty method)"); 605 StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart()); 606 const llvm::Triple &Triple = getContext().Target.getTriple(); 607 QualType IVART = Ivar->getType(); 608 bool IsCopy = PD->getSetterKind() == ObjCPropertyDecl::Copy; 609 bool IsAtomic = 610 !(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic); 611 612 // Determine if we should use an objc_setProperty call for 613 // this. Properties with 'copy' semantics always use it, as do 614 // non-atomic properties with 'release' semantics as long as we are 615 // not in gc-only mode. 616 if (IsCopy || 617 (CGM.getLangOptions().getGCMode() != LangOptions::GCOnly && 618 PD->getSetterKind() == ObjCPropertyDecl::Retain)) { 619 llvm::Value *SetPropertyFn = 620 CGM.getObjCRuntime().GetPropertySetFunction(); 621 622 if (!SetPropertyFn) { 623 CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy"); 624 FinishFunction(); 625 return; 626 } 627 628 // Emit objc_setProperty((id) self, _cmd, offset, arg, 629 // <is-atomic>, <is-copy>). 630 // FIXME: Can't this be simpler? This might even be worse than the 631 // corresponding gcc code. 632 CodeGenTypes &Types = CGM.getTypes(); 633 ValueDecl *Cmd = OMD->getCmdDecl(); 634 llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd"); 635 QualType IdTy = getContext().getObjCIdType(); 636 llvm::Value *SelfAsId = 637 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy)); 638 llvm::Value *Offset = EmitIvarOffset(IMP->getClassInterface(), Ivar); 639 llvm::Value *Arg = LocalDeclMap[*OMD->param_begin()]; 640 llvm::Value *ArgAsId = 641 Builder.CreateBitCast(Builder.CreateLoad(Arg, "arg"), 642 Types.ConvertType(IdTy)); 643 llvm::Value *True = 644 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1); 645 llvm::Value *False = 646 llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 0); 647 CallArgList Args; 648 Args.add(RValue::get(SelfAsId), IdTy); 649 Args.add(RValue::get(CmdVal), Cmd->getType()); 650 Args.add(RValue::get(Offset), getContext().getPointerDiffType()); 651 Args.add(RValue::get(ArgAsId), IdTy); 652 Args.add(RValue::get(IsAtomic ? True : False), getContext().BoolTy); 653 Args.add(RValue::get(IsCopy ? True : False), getContext().BoolTy); 654 // FIXME: We shouldn't need to get the function info here, the runtime 655 // already should have computed it to build the function. 656 EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args, 657 FunctionType::ExtInfo()), 658 SetPropertyFn, 659 ReturnValueSlot(), Args); 660 } else if (IsAtomic && hasAggregateLLVMType(IVART) && 661 !IVART->isAnyComplexType() && 662 IvarAssignHasTrvialAssignment(PID, IVART) && 663 ((Triple.getArch() == llvm::Triple::x86 && 664 (getContext().getTypeSizeInChars(IVART) 665 > CharUnits::fromQuantity(4))) || 666 (Triple.getArch() == llvm::Triple::x86_64 && 667 (getContext().getTypeSizeInChars(IVART) 668 > CharUnits::fromQuantity(8)))) 669 && CGM.getObjCRuntime().GetSetStructFunction()) { 670 // objc_copyStruct (&structIvar, &Arg, 671 // sizeof (struct something), true, false); 672 GenerateObjCAtomicSetterBody(OMD, Ivar); 673 } else if (PID->getSetterCXXAssignment()) { 674 EmitIgnoredExpr(PID->getSetterCXXAssignment()); 675 } else { 676 if (IsAtomic && 677 IVART->isScalarType() && 678 (Triple.getArch() == llvm::Triple::arm || 679 Triple.getArch() == llvm::Triple::thumb) && 680 (getContext().getTypeSizeInChars(IVART) 681 > CharUnits::fromQuantity(4)) && 682 CGM.getObjCRuntime().GetGetStructFunction()) { 683 GenerateObjCAtomicSetterBody(OMD, Ivar); 684 } 685 else if (IsAtomic && 686 (IVART->isScalarType() && !IVART->isRealFloatingType()) && 687 Triple.getArch() == llvm::Triple::x86 && 688 (getContext().getTypeSizeInChars(IVART) 689 > CharUnits::fromQuantity(4)) && 690 CGM.getObjCRuntime().GetGetStructFunction()) { 691 GenerateObjCAtomicSetterBody(OMD, Ivar); 692 } 693 else if (IsAtomic && 694 (IVART->isScalarType() && !IVART->isRealFloatingType()) && 695 Triple.getArch() == llvm::Triple::x86_64 && 696 (getContext().getTypeSizeInChars(IVART) 697 > CharUnits::fromQuantity(8)) && 698 CGM.getObjCRuntime().GetGetStructFunction()) { 699 GenerateObjCAtomicSetterBody(OMD, Ivar); 700 } 701 else { 702 // FIXME: Find a clean way to avoid AST node creation. 703 SourceLocation Loc = PID->getLocStart(); 704 ValueDecl *Self = OMD->getSelfDecl(); 705 ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl(); 706 DeclRefExpr Base(Self, Self->getType(), VK_RValue, Loc); 707 ParmVarDecl *ArgDecl = *OMD->param_begin(); 708 QualType T = ArgDecl->getType(); 709 if (T->isReferenceType()) 710 T = cast<ReferenceType>(T)->getPointeeType(); 711 DeclRefExpr Arg(ArgDecl, T, VK_LValue, Loc); 712 ObjCIvarRefExpr IvarRef(Ivar, Ivar->getType(), Loc, &Base, true, true); 713 714 // The property type can differ from the ivar type in some situations with 715 // Objective-C pointer types, we can always bit cast the RHS in these cases. 716 if (getContext().getCanonicalType(Ivar->getType()) != 717 getContext().getCanonicalType(ArgDecl->getType())) { 718 ImplicitCastExpr ArgCasted(ImplicitCastExpr::OnStack, 719 Ivar->getType(), CK_BitCast, &Arg, 720 VK_RValue); 721 BinaryOperator Assign(&IvarRef, &ArgCasted, BO_Assign, 722 Ivar->getType(), VK_RValue, OK_Ordinary, Loc); 723 EmitStmt(&Assign); 724 } else { 725 BinaryOperator Assign(&IvarRef, &Arg, BO_Assign, 726 Ivar->getType(), VK_RValue, OK_Ordinary, Loc); 727 EmitStmt(&Assign); 728 } 729 } 730 } 731 732 FinishFunction(); 733} 734 735namespace { 736 struct DestroyIvar : EHScopeStack::Cleanup { 737 private: 738 llvm::Value *addr; 739 const ObjCIvarDecl *ivar; 740 CodeGenFunction::Destroyer &destroyer; 741 bool useEHCleanupForArray; 742 public: 743 DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar, 744 CodeGenFunction::Destroyer *destroyer, 745 bool useEHCleanupForArray) 746 : addr(addr), ivar(ivar), destroyer(*destroyer), 747 useEHCleanupForArray(useEHCleanupForArray) {} 748 749 void Emit(CodeGenFunction &CGF, Flags flags) { 750 LValue lvalue 751 = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0); 752 CGF.emitDestroy(lvalue.getAddress(), ivar->getType(), destroyer, 753 flags.isForNormalCleanup() && useEHCleanupForArray); 754 } 755 }; 756} 757 758/// Like CodeGenFunction::destroyARCStrong, but do it with a call. 759static void destroyARCStrongWithStore(CodeGenFunction &CGF, 760 llvm::Value *addr, 761 QualType type) { 762 llvm::Value *null = getNullForVariable(addr); 763 CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true); 764} 765 766static void emitCXXDestructMethod(CodeGenFunction &CGF, 767 ObjCImplementationDecl *impl) { 768 CodeGenFunction::RunCleanupsScope scope(CGF); 769 770 llvm::Value *self = CGF.LoadObjCSelf(); 771 772 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 773 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 774 ivar; ivar = ivar->getNextIvar()) { 775 QualType type = ivar->getType(); 776 777 // Check whether the ivar is a destructible type. 778 QualType::DestructionKind dtorKind = type.isDestructedType(); 779 if (!dtorKind) continue; 780 781 CodeGenFunction::Destroyer *destroyer = 0; 782 783 // Use a call to objc_storeStrong to destroy strong ivars, for the 784 // general benefit of the tools. 785 if (dtorKind == QualType::DK_objc_strong_lifetime) { 786 destroyer = &destroyARCStrongWithStore; 787 788 // Otherwise use the default for the destruction kind. 789 } else { 790 destroyer = &CGF.getDestroyer(dtorKind); 791 } 792 793 CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind); 794 795 CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer, 796 cleanupKind & EHCleanup); 797 } 798 799 assert(scope.requiresCleanups() && "nothing to do in .cxx_destruct?"); 800} 801 802void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP, 803 ObjCMethodDecl *MD, 804 bool ctor) { 805 MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface()); 806 StartObjCMethod(MD, IMP->getClassInterface(), MD->getLocStart()); 807 808 // Emit .cxx_construct. 809 if (ctor) { 810 // Suppress the final autorelease in ARC. 811 AutoreleaseResult = false; 812 813 SmallVector<CXXCtorInitializer *, 8> IvarInitializers; 814 for (ObjCImplementationDecl::init_const_iterator B = IMP->init_begin(), 815 E = IMP->init_end(); B != E; ++B) { 816 CXXCtorInitializer *IvarInit = (*B); 817 FieldDecl *Field = IvarInit->getAnyMember(); 818 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field); 819 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), 820 LoadObjCSelf(), Ivar, 0); 821 EmitAggExpr(IvarInit->getInit(), 822 AggValueSlot::forLValue(LV, AggValueSlot::IsDestructed, 823 AggValueSlot::DoesNotNeedGCBarriers, 824 AggValueSlot::IsNotAliased)); 825 } 826 // constructor returns 'self'. 827 CodeGenTypes &Types = CGM.getTypes(); 828 QualType IdTy(CGM.getContext().getObjCIdType()); 829 llvm::Value *SelfAsId = 830 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy)); 831 EmitReturnOfRValue(RValue::get(SelfAsId), IdTy); 832 833 // Emit .cxx_destruct. 834 } else { 835 emitCXXDestructMethod(*this, IMP); 836 } 837 FinishFunction(); 838} 839 840bool CodeGenFunction::IndirectObjCSetterArg(const CGFunctionInfo &FI) { 841 CGFunctionInfo::const_arg_iterator it = FI.arg_begin(); 842 it++; it++; 843 const ABIArgInfo &AI = it->info; 844 // FIXME. Is this sufficient check? 845 return (AI.getKind() == ABIArgInfo::Indirect); 846} 847 848bool CodeGenFunction::IvarTypeWithAggrGCObjects(QualType Ty) { 849 if (CGM.getLangOptions().getGCMode() == LangOptions::NonGC) 850 return false; 851 if (const RecordType *FDTTy = Ty.getTypePtr()->getAs<RecordType>()) 852 return FDTTy->getDecl()->hasObjectMember(); 853 return false; 854} 855 856llvm::Value *CodeGenFunction::LoadObjCSelf() { 857 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl); 858 return Builder.CreateLoad(LocalDeclMap[OMD->getSelfDecl()], "self"); 859} 860 861QualType CodeGenFunction::TypeOfSelfObject() { 862 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl); 863 ImplicitParamDecl *selfDecl = OMD->getSelfDecl(); 864 const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>( 865 getContext().getCanonicalType(selfDecl->getType())); 866 return PTy->getPointeeType(); 867} 868 869LValue 870CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) { 871 // This is a special l-value that just issues sends when we load or 872 // store through it. 873 874 // For certain base kinds, we need to emit the base immediately. 875 llvm::Value *Base; 876 if (E->isSuperReceiver()) 877 Base = LoadObjCSelf(); 878 else if (E->isClassReceiver()) 879 Base = CGM.getObjCRuntime().GetClass(Builder, E->getClassReceiver()); 880 else 881 Base = EmitScalarExpr(E->getBase()); 882 return LValue::MakePropertyRef(E, Base); 883} 884 885static RValue GenerateMessageSendSuper(CodeGenFunction &CGF, 886 ReturnValueSlot Return, 887 QualType ResultType, 888 Selector S, 889 llvm::Value *Receiver, 890 const CallArgList &CallArgs) { 891 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CGF.CurFuncDecl); 892 bool isClassMessage = OMD->isClassMethod(); 893 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext()); 894 return CGF.CGM.getObjCRuntime() 895 .GenerateMessageSendSuper(CGF, Return, ResultType, 896 S, OMD->getClassInterface(), 897 isCategoryImpl, Receiver, 898 isClassMessage, CallArgs); 899} 900 901RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV, 902 ReturnValueSlot Return) { 903 const ObjCPropertyRefExpr *E = LV.getPropertyRefExpr(); 904 QualType ResultType = E->getGetterResultType(); 905 Selector S; 906 const ObjCMethodDecl *method; 907 if (E->isExplicitProperty()) { 908 const ObjCPropertyDecl *Property = E->getExplicitProperty(); 909 S = Property->getGetterName(); 910 method = Property->getGetterMethodDecl(); 911 } else { 912 method = E->getImplicitPropertyGetter(); 913 S = method->getSelector(); 914 } 915 916 llvm::Value *Receiver = LV.getPropertyRefBaseAddr(); 917 918 if (CGM.getLangOptions().ObjCAutoRefCount) { 919 QualType receiverType; 920 if (E->isSuperReceiver()) 921 receiverType = E->getSuperReceiverType(); 922 else if (E->isClassReceiver()) 923 receiverType = getContext().getObjCClassType(); 924 else 925 receiverType = E->getBase()->getType(); 926 } 927 928 // Accesses to 'super' follow a different code path. 929 if (E->isSuperReceiver()) 930 return AdjustRelatedResultType(*this, E, method, 931 GenerateMessageSendSuper(*this, Return, 932 ResultType, 933 S, Receiver, 934 CallArgList())); 935 const ObjCInterfaceDecl *ReceiverClass 936 = (E->isClassReceiver() ? E->getClassReceiver() : 0); 937 return AdjustRelatedResultType(*this, E, method, 938 CGM.getObjCRuntime(). 939 GenerateMessageSend(*this, Return, ResultType, S, 940 Receiver, CallArgList(), ReceiverClass)); 941} 942 943void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src, 944 LValue Dst) { 945 const ObjCPropertyRefExpr *E = Dst.getPropertyRefExpr(); 946 Selector S = E->getSetterSelector(); 947 QualType ArgType = E->getSetterArgType(); 948 949 // FIXME. Other than scalars, AST is not adequate for setter and 950 // getter type mismatches which require conversion. 951 if (Src.isScalar()) { 952 llvm::Value *SrcVal = Src.getScalarVal(); 953 QualType DstType = getContext().getCanonicalType(ArgType); 954 llvm::Type *DstTy = ConvertType(DstType); 955 if (SrcVal->getType() != DstTy) 956 Src = 957 RValue::get(EmitScalarConversion(SrcVal, E->getType(), DstType)); 958 } 959 960 CallArgList Args; 961 Args.add(Src, ArgType); 962 963 llvm::Value *Receiver = Dst.getPropertyRefBaseAddr(); 964 QualType ResultType = getContext().VoidTy; 965 966 if (E->isSuperReceiver()) { 967 GenerateMessageSendSuper(*this, ReturnValueSlot(), 968 ResultType, S, Receiver, Args); 969 return; 970 } 971 972 const ObjCInterfaceDecl *ReceiverClass 973 = (E->isClassReceiver() ? E->getClassReceiver() : 0); 974 975 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(), 976 ResultType, S, Receiver, Args, 977 ReceiverClass); 978} 979 980void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){ 981 llvm::Constant *EnumerationMutationFn = 982 CGM.getObjCRuntime().EnumerationMutationFunction(); 983 984 if (!EnumerationMutationFn) { 985 CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime"); 986 return; 987 } 988 989 CGDebugInfo *DI = getDebugInfo(); 990 if (DI) { 991 DI->setLocation(S.getSourceRange().getBegin()); 992 DI->EmitRegionStart(Builder); 993 } 994 995 // The local variable comes into scope immediately. 996 AutoVarEmission variable = AutoVarEmission::invalid(); 997 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) 998 variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl())); 999 1000 JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end"); 1001 1002 // Fast enumeration state. 1003 QualType StateTy = CGM.getObjCFastEnumerationStateType(); 1004 llvm::Value *StatePtr = CreateMemTemp(StateTy, "state.ptr"); 1005 EmitNullInitialization(StatePtr, StateTy); 1006 1007 // Number of elements in the items array. 1008 static const unsigned NumItems = 16; 1009 1010 // Fetch the countByEnumeratingWithState:objects:count: selector. 1011 IdentifierInfo *II[] = { 1012 &CGM.getContext().Idents.get("countByEnumeratingWithState"), 1013 &CGM.getContext().Idents.get("objects"), 1014 &CGM.getContext().Idents.get("count") 1015 }; 1016 Selector FastEnumSel = 1017 CGM.getContext().Selectors.getSelector(llvm::array_lengthof(II), &II[0]); 1018 1019 QualType ItemsTy = 1020 getContext().getConstantArrayType(getContext().getObjCIdType(), 1021 llvm::APInt(32, NumItems), 1022 ArrayType::Normal, 0); 1023 llvm::Value *ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr"); 1024 1025 // Emit the collection pointer. In ARC, we do a retain. 1026 llvm::Value *Collection; 1027 if (getLangOptions().ObjCAutoRefCount) { 1028 Collection = EmitARCRetainScalarExpr(S.getCollection()); 1029 1030 // Enter a cleanup to do the release. 1031 EmitObjCConsumeObject(S.getCollection()->getType(), Collection); 1032 } else { 1033 Collection = EmitScalarExpr(S.getCollection()); 1034 } 1035 1036 // The 'continue' label needs to appear within the cleanup for the 1037 // collection object. 1038 JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next"); 1039 1040 // Send it our message: 1041 CallArgList Args; 1042 1043 // The first argument is a temporary of the enumeration-state type. 1044 Args.add(RValue::get(StatePtr), getContext().getPointerType(StateTy)); 1045 1046 // The second argument is a temporary array with space for NumItems 1047 // pointers. We'll actually be loading elements from the array 1048 // pointer written into the control state; this buffer is so that 1049 // collections that *aren't* backed by arrays can still queue up 1050 // batches of elements. 1051 Args.add(RValue::get(ItemsPtr), getContext().getPointerType(ItemsTy)); 1052 1053 // The third argument is the capacity of that temporary array. 1054 llvm::Type *UnsignedLongLTy = ConvertType(getContext().UnsignedLongTy); 1055 llvm::Constant *Count = llvm::ConstantInt::get(UnsignedLongLTy, NumItems); 1056 Args.add(RValue::get(Count), getContext().UnsignedLongTy); 1057 1058 // Start the enumeration. 1059 RValue CountRV = 1060 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(), 1061 getContext().UnsignedLongTy, 1062 FastEnumSel, 1063 Collection, Args); 1064 1065 // The initial number of objects that were returned in the buffer. 1066 llvm::Value *initialBufferLimit = CountRV.getScalarVal(); 1067 1068 llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty"); 1069 llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit"); 1070 1071 llvm::Value *zero = llvm::Constant::getNullValue(UnsignedLongLTy); 1072 1073 // If the limit pointer was zero to begin with, the collection is 1074 // empty; skip all this. 1075 Builder.CreateCondBr(Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"), 1076 EmptyBB, LoopInitBB); 1077 1078 // Otherwise, initialize the loop. 1079 EmitBlock(LoopInitBB); 1080 1081 // Save the initial mutations value. This is the value at an 1082 // address that was written into the state object by 1083 // countByEnumeratingWithState:objects:count:. 1084 llvm::Value *StateMutationsPtrPtr = 1085 Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr"); 1086 llvm::Value *StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, 1087 "mutationsptr"); 1088 1089 llvm::Value *initialMutations = 1090 Builder.CreateLoad(StateMutationsPtr, "forcoll.initial-mutations"); 1091 1092 // Start looping. This is the point we return to whenever we have a 1093 // fresh, non-empty batch of objects. 1094 llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody"); 1095 EmitBlock(LoopBodyBB); 1096 1097 // The current index into the buffer. 1098 llvm::PHINode *index = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.index"); 1099 index->addIncoming(zero, LoopInitBB); 1100 1101 // The current buffer size. 1102 llvm::PHINode *count = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.count"); 1103 count->addIncoming(initialBufferLimit, LoopInitBB); 1104 1105 // Check whether the mutations value has changed from where it was 1106 // at start. StateMutationsPtr should actually be invariant between 1107 // refreshes. 1108 StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr"); 1109 llvm::Value *currentMutations 1110 = Builder.CreateLoad(StateMutationsPtr, "statemutations"); 1111 1112 llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated"); 1113 llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated"); 1114 1115 Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations), 1116 WasNotMutatedBB, WasMutatedBB); 1117 1118 // If so, call the enumeration-mutation function. 1119 EmitBlock(WasMutatedBB); 1120 llvm::Value *V = 1121 Builder.CreateBitCast(Collection, 1122 ConvertType(getContext().getObjCIdType()), 1123 "tmp"); 1124 CallArgList Args2; 1125 Args2.add(RValue::get(V), getContext().getObjCIdType()); 1126 // FIXME: We shouldn't need to get the function info here, the runtime already 1127 // should have computed it to build the function. 1128 EmitCall(CGM.getTypes().getFunctionInfo(getContext().VoidTy, Args2, 1129 FunctionType::ExtInfo()), 1130 EnumerationMutationFn, ReturnValueSlot(), Args2); 1131 1132 // Otherwise, or if the mutation function returns, just continue. 1133 EmitBlock(WasNotMutatedBB); 1134 1135 // Initialize the element variable. 1136 RunCleanupsScope elementVariableScope(*this); 1137 bool elementIsVariable; 1138 LValue elementLValue; 1139 QualType elementType; 1140 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) { 1141 // Initialize the variable, in case it's a __block variable or something. 1142 EmitAutoVarInit(variable); 1143 1144 const VarDecl* D = cast<VarDecl>(SD->getSingleDecl()); 1145 DeclRefExpr tempDRE(const_cast<VarDecl*>(D), D->getType(), 1146 VK_LValue, SourceLocation()); 1147 elementLValue = EmitLValue(&tempDRE); 1148 elementType = D->getType(); 1149 elementIsVariable = true; 1150 1151 if (D->isARCPseudoStrong()) 1152 elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone); 1153 } else { 1154 elementLValue = LValue(); // suppress warning 1155 elementType = cast<Expr>(S.getElement())->getType(); 1156 elementIsVariable = false; 1157 } 1158 llvm::Type *convertedElementType = ConvertType(elementType); 1159 1160 // Fetch the buffer out of the enumeration state. 1161 // TODO: this pointer should actually be invariant between 1162 // refreshes, which would help us do certain loop optimizations. 1163 llvm::Value *StateItemsPtr = 1164 Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr"); 1165 llvm::Value *EnumStateItems = 1166 Builder.CreateLoad(StateItemsPtr, "stateitems"); 1167 1168 // Fetch the value at the current index from the buffer. 1169 llvm::Value *CurrentItemPtr = 1170 Builder.CreateGEP(EnumStateItems, index, "currentitem.ptr"); 1171 llvm::Value *CurrentItem = Builder.CreateLoad(CurrentItemPtr); 1172 1173 // Cast that value to the right type. 1174 CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType, 1175 "currentitem"); 1176 1177 // Make sure we have an l-value. Yes, this gets evaluated every 1178 // time through the loop. 1179 if (!elementIsVariable) { 1180 elementLValue = EmitLValue(cast<Expr>(S.getElement())); 1181 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue); 1182 } else { 1183 EmitScalarInit(CurrentItem, elementLValue); 1184 } 1185 1186 // If we do have an element variable, this assignment is the end of 1187 // its initialization. 1188 if (elementIsVariable) 1189 EmitAutoVarCleanups(variable); 1190 1191 // Perform the loop body, setting up break and continue labels. 1192 BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody)); 1193 { 1194 RunCleanupsScope Scope(*this); 1195 EmitStmt(S.getBody()); 1196 } 1197 BreakContinueStack.pop_back(); 1198 1199 // Destroy the element variable now. 1200 elementVariableScope.ForceCleanup(); 1201 1202 // Check whether there are more elements. 1203 EmitBlock(AfterBody.getBlock()); 1204 1205 llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch"); 1206 1207 // First we check in the local buffer. 1208 llvm::Value *indexPlusOne 1209 = Builder.CreateAdd(index, llvm::ConstantInt::get(UnsignedLongLTy, 1)); 1210 1211 // If we haven't overrun the buffer yet, we can continue. 1212 Builder.CreateCondBr(Builder.CreateICmpULT(indexPlusOne, count), 1213 LoopBodyBB, FetchMoreBB); 1214 1215 index->addIncoming(indexPlusOne, AfterBody.getBlock()); 1216 count->addIncoming(count, AfterBody.getBlock()); 1217 1218 // Otherwise, we have to fetch more elements. 1219 EmitBlock(FetchMoreBB); 1220 1221 CountRV = 1222 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(), 1223 getContext().UnsignedLongTy, 1224 FastEnumSel, 1225 Collection, Args); 1226 1227 // If we got a zero count, we're done. 1228 llvm::Value *refetchCount = CountRV.getScalarVal(); 1229 1230 // (note that the message send might split FetchMoreBB) 1231 index->addIncoming(zero, Builder.GetInsertBlock()); 1232 count->addIncoming(refetchCount, Builder.GetInsertBlock()); 1233 1234 Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero), 1235 EmptyBB, LoopBodyBB); 1236 1237 // No more elements. 1238 EmitBlock(EmptyBB); 1239 1240 if (!elementIsVariable) { 1241 // If the element was not a declaration, set it to be null. 1242 1243 llvm::Value *null = llvm::Constant::getNullValue(convertedElementType); 1244 elementLValue = EmitLValue(cast<Expr>(S.getElement())); 1245 EmitStoreThroughLValue(RValue::get(null), elementLValue); 1246 } 1247 1248 if (DI) { 1249 DI->setLocation(S.getSourceRange().getEnd()); 1250 DI->EmitRegionEnd(Builder); 1251 } 1252 1253 // Leave the cleanup we entered in ARC. 1254 if (getLangOptions().ObjCAutoRefCount) 1255 PopCleanupBlock(); 1256 1257 EmitBlock(LoopEnd.getBlock()); 1258} 1259 1260void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) { 1261 CGM.getObjCRuntime().EmitTryStmt(*this, S); 1262} 1263 1264void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) { 1265 CGM.getObjCRuntime().EmitThrowStmt(*this, S); 1266} 1267 1268void CodeGenFunction::EmitObjCAtSynchronizedStmt( 1269 const ObjCAtSynchronizedStmt &S) { 1270 CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S); 1271} 1272 1273/// Produce the code for a CK_ObjCProduceObject. Just does a 1274/// primitive retain. 1275llvm::Value *CodeGenFunction::EmitObjCProduceObject(QualType type, 1276 llvm::Value *value) { 1277 return EmitARCRetain(type, value); 1278} 1279 1280namespace { 1281 struct CallObjCRelease : EHScopeStack::Cleanup { 1282 CallObjCRelease(llvm::Value *object) : object(object) {} 1283 llvm::Value *object; 1284 1285 void Emit(CodeGenFunction &CGF, Flags flags) { 1286 CGF.EmitARCRelease(object, /*precise*/ true); 1287 } 1288 }; 1289} 1290 1291/// Produce the code for a CK_ObjCConsumeObject. Does a primitive 1292/// release at the end of the full-expression. 1293llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type, 1294 llvm::Value *object) { 1295 // If we're in a conditional branch, we need to make the cleanup 1296 // conditional. 1297 pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object); 1298 return object; 1299} 1300 1301llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type, 1302 llvm::Value *value) { 1303 return EmitARCRetainAutorelease(type, value); 1304} 1305 1306 1307static llvm::Constant *createARCRuntimeFunction(CodeGenModule &CGM, 1308 llvm::FunctionType *type, 1309 StringRef fnName) { 1310 llvm::Constant *fn = CGM.CreateRuntimeFunction(type, fnName); 1311 1312 // In -fobjc-no-arc-runtime, emit weak references to the runtime 1313 // support library. 1314 if (!CGM.getCodeGenOpts().ObjCRuntimeHasARC) 1315 if (llvm::Function *f = dyn_cast<llvm::Function>(fn)) 1316 f->setLinkage(llvm::Function::ExternalWeakLinkage); 1317 1318 return fn; 1319} 1320 1321/// Perform an operation having the signature 1322/// i8* (i8*) 1323/// where a null input causes a no-op and returns null. 1324static llvm::Value *emitARCValueOperation(CodeGenFunction &CGF, 1325 llvm::Value *value, 1326 llvm::Constant *&fn, 1327 StringRef fnName) { 1328 if (isa<llvm::ConstantPointerNull>(value)) return value; 1329 1330 if (!fn) { 1331 std::vector<llvm::Type*> args(1, CGF.Int8PtrTy); 1332 llvm::FunctionType *fnType = 1333 llvm::FunctionType::get(CGF.Int8PtrTy, args, false); 1334 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName); 1335 } 1336 1337 // Cast the argument to 'id'. 1338 llvm::Type *origType = value->getType(); 1339 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy); 1340 1341 // Call the function. 1342 llvm::CallInst *call = CGF.Builder.CreateCall(fn, value); 1343 call->setDoesNotThrow(); 1344 1345 // Cast the result back to the original type. 1346 return CGF.Builder.CreateBitCast(call, origType); 1347} 1348 1349/// Perform an operation having the following signature: 1350/// i8* (i8**) 1351static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF, 1352 llvm::Value *addr, 1353 llvm::Constant *&fn, 1354 StringRef fnName) { 1355 if (!fn) { 1356 std::vector<llvm::Type*> args(1, CGF.Int8PtrPtrTy); 1357 llvm::FunctionType *fnType = 1358 llvm::FunctionType::get(CGF.Int8PtrTy, args, false); 1359 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName); 1360 } 1361 1362 // Cast the argument to 'id*'. 1363 llvm::Type *origType = addr->getType(); 1364 addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy); 1365 1366 // Call the function. 1367 llvm::CallInst *call = CGF.Builder.CreateCall(fn, addr); 1368 call->setDoesNotThrow(); 1369 1370 // Cast the result back to a dereference of the original type. 1371 llvm::Value *result = call; 1372 if (origType != CGF.Int8PtrPtrTy) 1373 result = CGF.Builder.CreateBitCast(result, 1374 cast<llvm::PointerType>(origType)->getElementType()); 1375 1376 return result; 1377} 1378 1379/// Perform an operation having the following signature: 1380/// i8* (i8**, i8*) 1381static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF, 1382 llvm::Value *addr, 1383 llvm::Value *value, 1384 llvm::Constant *&fn, 1385 StringRef fnName, 1386 bool ignored) { 1387 assert(cast<llvm::PointerType>(addr->getType())->getElementType() 1388 == value->getType()); 1389 1390 if (!fn) { 1391 std::vector<llvm::Type*> argTypes(2); 1392 argTypes[0] = CGF.Int8PtrPtrTy; 1393 argTypes[1] = CGF.Int8PtrTy; 1394 1395 llvm::FunctionType *fnType 1396 = llvm::FunctionType::get(CGF.Int8PtrTy, argTypes, false); 1397 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName); 1398 } 1399 1400 llvm::Type *origType = value->getType(); 1401 1402 addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy); 1403 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy); 1404 1405 llvm::CallInst *result = CGF.Builder.CreateCall2(fn, addr, value); 1406 result->setDoesNotThrow(); 1407 1408 if (ignored) return 0; 1409 1410 return CGF.Builder.CreateBitCast(result, origType); 1411} 1412 1413/// Perform an operation having the following signature: 1414/// void (i8**, i8**) 1415static void emitARCCopyOperation(CodeGenFunction &CGF, 1416 llvm::Value *dst, 1417 llvm::Value *src, 1418 llvm::Constant *&fn, 1419 StringRef fnName) { 1420 assert(dst->getType() == src->getType()); 1421 1422 if (!fn) { 1423 std::vector<llvm::Type*> argTypes(2, CGF.Int8PtrPtrTy); 1424 llvm::FunctionType *fnType 1425 = llvm::FunctionType::get(CGF.Builder.getVoidTy(), argTypes, false); 1426 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName); 1427 } 1428 1429 dst = CGF.Builder.CreateBitCast(dst, CGF.Int8PtrPtrTy); 1430 src = CGF.Builder.CreateBitCast(src, CGF.Int8PtrPtrTy); 1431 1432 llvm::CallInst *result = CGF.Builder.CreateCall2(fn, dst, src); 1433 result->setDoesNotThrow(); 1434} 1435 1436/// Produce the code to do a retain. Based on the type, calls one of: 1437/// call i8* @objc_retain(i8* %value) 1438/// call i8* @objc_retainBlock(i8* %value) 1439llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) { 1440 if (type->isBlockPointerType()) 1441 return EmitARCRetainBlock(value); 1442 else 1443 return EmitARCRetainNonBlock(value); 1444} 1445 1446/// Retain the given object, with normal retain semantics. 1447/// call i8* @objc_retain(i8* %value) 1448llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) { 1449 return emitARCValueOperation(*this, value, 1450 CGM.getARCEntrypoints().objc_retain, 1451 "objc_retain"); 1452} 1453 1454/// Retain the given block, with _Block_copy semantics. 1455/// call i8* @objc_retainBlock(i8* %value) 1456llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value) { 1457 return emitARCValueOperation(*this, value, 1458 CGM.getARCEntrypoints().objc_retainBlock, 1459 "objc_retainBlock"); 1460} 1461 1462/// Retain the given object which is the result of a function call. 1463/// call i8* @objc_retainAutoreleasedReturnValue(i8* %value) 1464/// 1465/// Yes, this function name is one character away from a different 1466/// call with completely different semantics. 1467llvm::Value * 1468CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) { 1469 // Fetch the void(void) inline asm which marks that we're going to 1470 // retain the autoreleased return value. 1471 llvm::InlineAsm *&marker 1472 = CGM.getARCEntrypoints().retainAutoreleasedReturnValueMarker; 1473 if (!marker) { 1474 StringRef assembly 1475 = CGM.getTargetCodeGenInfo() 1476 .getARCRetainAutoreleasedReturnValueMarker(); 1477 1478 // If we have an empty assembly string, there's nothing to do. 1479 if (assembly.empty()) { 1480 1481 // Otherwise, at -O0, build an inline asm that we're going to call 1482 // in a moment. 1483 } else if (CGM.getCodeGenOpts().OptimizationLevel == 0) { 1484 llvm::FunctionType *type = 1485 llvm::FunctionType::get(llvm::Type::getVoidTy(getLLVMContext()), 1486 /*variadic*/ false); 1487 1488 marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true); 1489 1490 // If we're at -O1 and above, we don't want to litter the code 1491 // with this marker yet, so leave a breadcrumb for the ARC 1492 // optimizer to pick up. 1493 } else { 1494 llvm::NamedMDNode *metadata = 1495 CGM.getModule().getOrInsertNamedMetadata( 1496 "clang.arc.retainAutoreleasedReturnValueMarker"); 1497 assert(metadata->getNumOperands() <= 1); 1498 if (metadata->getNumOperands() == 0) { 1499 llvm::Value *string = llvm::MDString::get(getLLVMContext(), assembly); 1500 metadata->addOperand(llvm::MDNode::get(getLLVMContext(), string)); 1501 } 1502 } 1503 } 1504 1505 // Call the marker asm if we made one, which we do only at -O0. 1506 if (marker) Builder.CreateCall(marker); 1507 1508 return emitARCValueOperation(*this, value, 1509 CGM.getARCEntrypoints().objc_retainAutoreleasedReturnValue, 1510 "objc_retainAutoreleasedReturnValue"); 1511} 1512 1513/// Release the given object. 1514/// call void @objc_release(i8* %value) 1515void CodeGenFunction::EmitARCRelease(llvm::Value *value, bool precise) { 1516 if (isa<llvm::ConstantPointerNull>(value)) return; 1517 1518 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_release; 1519 if (!fn) { 1520 std::vector<llvm::Type*> args(1, Int8PtrTy); 1521 llvm::FunctionType *fnType = 1522 llvm::FunctionType::get(Builder.getVoidTy(), args, false); 1523 fn = createARCRuntimeFunction(CGM, fnType, "objc_release"); 1524 } 1525 1526 // Cast the argument to 'id'. 1527 value = Builder.CreateBitCast(value, Int8PtrTy); 1528 1529 // Call objc_release. 1530 llvm::CallInst *call = Builder.CreateCall(fn, value); 1531 call->setDoesNotThrow(); 1532 1533 if (!precise) { 1534 SmallVector<llvm::Value*,1> args; 1535 call->setMetadata("clang.imprecise_release", 1536 llvm::MDNode::get(Builder.getContext(), args)); 1537 } 1538} 1539 1540/// Store into a strong object. Always calls this: 1541/// call void @objc_storeStrong(i8** %addr, i8* %value) 1542llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(llvm::Value *addr, 1543 llvm::Value *value, 1544 bool ignored) { 1545 assert(cast<llvm::PointerType>(addr->getType())->getElementType() 1546 == value->getType()); 1547 1548 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_storeStrong; 1549 if (!fn) { 1550 llvm::Type *argTypes[] = { Int8PtrPtrTy, Int8PtrTy }; 1551 llvm::FunctionType *fnType 1552 = llvm::FunctionType::get(Builder.getVoidTy(), argTypes, false); 1553 fn = createARCRuntimeFunction(CGM, fnType, "objc_storeStrong"); 1554 } 1555 1556 addr = Builder.CreateBitCast(addr, Int8PtrPtrTy); 1557 llvm::Value *castValue = Builder.CreateBitCast(value, Int8PtrTy); 1558 1559 Builder.CreateCall2(fn, addr, castValue)->setDoesNotThrow(); 1560 1561 if (ignored) return 0; 1562 return value; 1563} 1564 1565/// Store into a strong object. Sometimes calls this: 1566/// call void @objc_storeStrong(i8** %addr, i8* %value) 1567/// Other times, breaks it down into components. 1568llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst, 1569 llvm::Value *newValue, 1570 bool ignored) { 1571 QualType type = dst.getType(); 1572 bool isBlock = type->isBlockPointerType(); 1573 1574 // Use a store barrier at -O0 unless this is a block type or the 1575 // lvalue is inadequately aligned. 1576 if (shouldUseFusedARCCalls() && 1577 !isBlock && 1578 !(dst.getAlignment() && dst.getAlignment() < PointerAlignInBytes)) { 1579 return EmitARCStoreStrongCall(dst.getAddress(), newValue, ignored); 1580 } 1581 1582 // Otherwise, split it out. 1583 1584 // Retain the new value. 1585 newValue = EmitARCRetain(type, newValue); 1586 1587 // Read the old value. 1588 llvm::Value *oldValue = EmitLoadOfScalar(dst); 1589 1590 // Store. We do this before the release so that any deallocs won't 1591 // see the old value. 1592 EmitStoreOfScalar(newValue, dst); 1593 1594 // Finally, release the old value. 1595 EmitARCRelease(oldValue, /*precise*/ false); 1596 1597 return newValue; 1598} 1599 1600/// Autorelease the given object. 1601/// call i8* @objc_autorelease(i8* %value) 1602llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) { 1603 return emitARCValueOperation(*this, value, 1604 CGM.getARCEntrypoints().objc_autorelease, 1605 "objc_autorelease"); 1606} 1607 1608/// Autorelease the given object. 1609/// call i8* @objc_autoreleaseReturnValue(i8* %value) 1610llvm::Value * 1611CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) { 1612 return emitARCValueOperation(*this, value, 1613 CGM.getARCEntrypoints().objc_autoreleaseReturnValue, 1614 "objc_autoreleaseReturnValue"); 1615} 1616 1617/// Do a fused retain/autorelease of the given object. 1618/// call i8* @objc_retainAutoreleaseReturnValue(i8* %value) 1619llvm::Value * 1620CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) { 1621 return emitARCValueOperation(*this, value, 1622 CGM.getARCEntrypoints().objc_retainAutoreleaseReturnValue, 1623 "objc_retainAutoreleaseReturnValue"); 1624} 1625 1626/// Do a fused retain/autorelease of the given object. 1627/// call i8* @objc_retainAutorelease(i8* %value) 1628/// or 1629/// %retain = call i8* @objc_retainBlock(i8* %value) 1630/// call i8* @objc_autorelease(i8* %retain) 1631llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type, 1632 llvm::Value *value) { 1633 if (!type->isBlockPointerType()) 1634 return EmitARCRetainAutoreleaseNonBlock(value); 1635 1636 if (isa<llvm::ConstantPointerNull>(value)) return value; 1637 1638 llvm::Type *origType = value->getType(); 1639 value = Builder.CreateBitCast(value, Int8PtrTy); 1640 value = EmitARCRetainBlock(value); 1641 value = EmitARCAutorelease(value); 1642 return Builder.CreateBitCast(value, origType); 1643} 1644 1645/// Do a fused retain/autorelease of the given object. 1646/// call i8* @objc_retainAutorelease(i8* %value) 1647llvm::Value * 1648CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) { 1649 return emitARCValueOperation(*this, value, 1650 CGM.getARCEntrypoints().objc_retainAutorelease, 1651 "objc_retainAutorelease"); 1652} 1653 1654/// i8* @objc_loadWeak(i8** %addr) 1655/// Essentially objc_autorelease(objc_loadWeakRetained(addr)). 1656llvm::Value *CodeGenFunction::EmitARCLoadWeak(llvm::Value *addr) { 1657 return emitARCLoadOperation(*this, addr, 1658 CGM.getARCEntrypoints().objc_loadWeak, 1659 "objc_loadWeak"); 1660} 1661 1662/// i8* @objc_loadWeakRetained(i8** %addr) 1663llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(llvm::Value *addr) { 1664 return emitARCLoadOperation(*this, addr, 1665 CGM.getARCEntrypoints().objc_loadWeakRetained, 1666 "objc_loadWeakRetained"); 1667} 1668 1669/// i8* @objc_storeWeak(i8** %addr, i8* %value) 1670/// Returns %value. 1671llvm::Value *CodeGenFunction::EmitARCStoreWeak(llvm::Value *addr, 1672 llvm::Value *value, 1673 bool ignored) { 1674 return emitARCStoreOperation(*this, addr, value, 1675 CGM.getARCEntrypoints().objc_storeWeak, 1676 "objc_storeWeak", ignored); 1677} 1678 1679/// i8* @objc_initWeak(i8** %addr, i8* %value) 1680/// Returns %value. %addr is known to not have a current weak entry. 1681/// Essentially equivalent to: 1682/// *addr = nil; objc_storeWeak(addr, value); 1683void CodeGenFunction::EmitARCInitWeak(llvm::Value *addr, llvm::Value *value) { 1684 // If we're initializing to null, just write null to memory; no need 1685 // to get the runtime involved. But don't do this if optimization 1686 // is enabled, because accounting for this would make the optimizer 1687 // much more complicated. 1688 if (isa<llvm::ConstantPointerNull>(value) && 1689 CGM.getCodeGenOpts().OptimizationLevel == 0) { 1690 Builder.CreateStore(value, addr); 1691 return; 1692 } 1693 1694 emitARCStoreOperation(*this, addr, value, 1695 CGM.getARCEntrypoints().objc_initWeak, 1696 "objc_initWeak", /*ignored*/ true); 1697} 1698 1699/// void @objc_destroyWeak(i8** %addr) 1700/// Essentially objc_storeWeak(addr, nil). 1701void CodeGenFunction::EmitARCDestroyWeak(llvm::Value *addr) { 1702 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_destroyWeak; 1703 if (!fn) { 1704 std::vector<llvm::Type*> args(1, Int8PtrPtrTy); 1705 llvm::FunctionType *fnType = 1706 llvm::FunctionType::get(Builder.getVoidTy(), args, false); 1707 fn = createARCRuntimeFunction(CGM, fnType, "objc_destroyWeak"); 1708 } 1709 1710 // Cast the argument to 'id*'. 1711 addr = Builder.CreateBitCast(addr, Int8PtrPtrTy); 1712 1713 llvm::CallInst *call = Builder.CreateCall(fn, addr); 1714 call->setDoesNotThrow(); 1715} 1716 1717/// void @objc_moveWeak(i8** %dest, i8** %src) 1718/// Disregards the current value in %dest. Leaves %src pointing to nothing. 1719/// Essentially (objc_copyWeak(dest, src), objc_destroyWeak(src)). 1720void CodeGenFunction::EmitARCMoveWeak(llvm::Value *dst, llvm::Value *src) { 1721 emitARCCopyOperation(*this, dst, src, 1722 CGM.getARCEntrypoints().objc_moveWeak, 1723 "objc_moveWeak"); 1724} 1725 1726/// void @objc_copyWeak(i8** %dest, i8** %src) 1727/// Disregards the current value in %dest. Essentially 1728/// objc_release(objc_initWeak(dest, objc_readWeakRetained(src))) 1729void CodeGenFunction::EmitARCCopyWeak(llvm::Value *dst, llvm::Value *src) { 1730 emitARCCopyOperation(*this, dst, src, 1731 CGM.getARCEntrypoints().objc_copyWeak, 1732 "objc_copyWeak"); 1733} 1734 1735/// Produce the code to do a objc_autoreleasepool_push. 1736/// call i8* @objc_autoreleasePoolPush(void) 1737llvm::Value *CodeGenFunction::EmitObjCAutoreleasePoolPush() { 1738 llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPush; 1739 if (!fn) { 1740 llvm::FunctionType *fnType = 1741 llvm::FunctionType::get(Int8PtrTy, false); 1742 fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPush"); 1743 } 1744 1745 llvm::CallInst *call = Builder.CreateCall(fn); 1746 call->setDoesNotThrow(); 1747 1748 return call; 1749} 1750 1751/// Produce the code to do a primitive release. 1752/// call void @objc_autoreleasePoolPop(i8* %ptr) 1753void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) { 1754 assert(value->getType() == Int8PtrTy); 1755 1756 llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPop; 1757 if (!fn) { 1758 std::vector<llvm::Type*> args(1, Int8PtrTy); 1759 llvm::FunctionType *fnType = 1760 llvm::FunctionType::get(Builder.getVoidTy(), args, false); 1761 1762 // We don't want to use a weak import here; instead we should not 1763 // fall into this path. 1764 fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPop"); 1765 } 1766 1767 llvm::CallInst *call = Builder.CreateCall(fn, value); 1768 call->setDoesNotThrow(); 1769} 1770 1771/// Produce the code to do an MRR version objc_autoreleasepool_push. 1772/// Which is: [[NSAutoreleasePool alloc] init]; 1773/// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class. 1774/// init is declared as: - (id) init; in its NSObject super class. 1775/// 1776llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() { 1777 CGObjCRuntime &Runtime = CGM.getObjCRuntime(); 1778 llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(Builder); 1779 // [NSAutoreleasePool alloc] 1780 IdentifierInfo *II = &CGM.getContext().Idents.get("alloc"); 1781 Selector AllocSel = getContext().Selectors.getSelector(0, &II); 1782 CallArgList Args; 1783 RValue AllocRV = 1784 Runtime.GenerateMessageSend(*this, ReturnValueSlot(), 1785 getContext().getObjCIdType(), 1786 AllocSel, Receiver, Args); 1787 1788 // [Receiver init] 1789 Receiver = AllocRV.getScalarVal(); 1790 II = &CGM.getContext().Idents.get("init"); 1791 Selector InitSel = getContext().Selectors.getSelector(0, &II); 1792 RValue InitRV = 1793 Runtime.GenerateMessageSend(*this, ReturnValueSlot(), 1794 getContext().getObjCIdType(), 1795 InitSel, Receiver, Args); 1796 return InitRV.getScalarVal(); 1797} 1798 1799/// Produce the code to do a primitive release. 1800/// [tmp drain]; 1801void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) { 1802 IdentifierInfo *II = &CGM.getContext().Idents.get("drain"); 1803 Selector DrainSel = getContext().Selectors.getSelector(0, &II); 1804 CallArgList Args; 1805 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(), 1806 getContext().VoidTy, DrainSel, Arg, Args); 1807} 1808 1809void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF, 1810 llvm::Value *addr, 1811 QualType type) { 1812 llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy"); 1813 CGF.EmitARCRelease(ptr, /*precise*/ true); 1814} 1815 1816void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF, 1817 llvm::Value *addr, 1818 QualType type) { 1819 llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy"); 1820 CGF.EmitARCRelease(ptr, /*precise*/ false); 1821} 1822 1823void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF, 1824 llvm::Value *addr, 1825 QualType type) { 1826 CGF.EmitARCDestroyWeak(addr); 1827} 1828 1829namespace { 1830 struct CallObjCAutoreleasePoolObject : EHScopeStack::Cleanup { 1831 llvm::Value *Token; 1832 1833 CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {} 1834 1835 void Emit(CodeGenFunction &CGF, Flags flags) { 1836 CGF.EmitObjCAutoreleasePoolPop(Token); 1837 } 1838 }; 1839 struct CallObjCMRRAutoreleasePoolObject : EHScopeStack::Cleanup { 1840 llvm::Value *Token; 1841 1842 CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {} 1843 1844 void Emit(CodeGenFunction &CGF, Flags flags) { 1845 CGF.EmitObjCMRRAutoreleasePoolPop(Token); 1846 } 1847 }; 1848} 1849 1850void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) { 1851 if (CGM.getLangOptions().ObjCAutoRefCount) 1852 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr); 1853 else 1854 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr); 1855} 1856 1857static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF, 1858 LValue lvalue, 1859 QualType type) { 1860 switch (type.getObjCLifetime()) { 1861 case Qualifiers::OCL_None: 1862 case Qualifiers::OCL_ExplicitNone: 1863 case Qualifiers::OCL_Strong: 1864 case Qualifiers::OCL_Autoreleasing: 1865 return TryEmitResult(CGF.EmitLoadOfLValue(lvalue).getScalarVal(), 1866 false); 1867 1868 case Qualifiers::OCL_Weak: 1869 return TryEmitResult(CGF.EmitARCLoadWeakRetained(lvalue.getAddress()), 1870 true); 1871 } 1872 1873 llvm_unreachable("impossible lifetime!"); 1874 return TryEmitResult(); 1875} 1876 1877static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF, 1878 const Expr *e) { 1879 e = e->IgnoreParens(); 1880 QualType type = e->getType(); 1881 1882 // As a very special optimization, in ARC++, if the l-value is the 1883 // result of a non-volatile assignment, do a simple retain of the 1884 // result of the call to objc_storeWeak instead of reloading. 1885 if (CGF.getLangOptions().CPlusPlus && 1886 !type.isVolatileQualified() && 1887 type.getObjCLifetime() == Qualifiers::OCL_Weak && 1888 isa<BinaryOperator>(e) && 1889 cast<BinaryOperator>(e)->getOpcode() == BO_Assign) 1890 return TryEmitResult(CGF.EmitScalarExpr(e), false); 1891 1892 return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type); 1893} 1894 1895static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF, 1896 llvm::Value *value); 1897 1898/// Given that the given expression is some sort of call (which does 1899/// not return retained), emit a retain following it. 1900static llvm::Value *emitARCRetainCall(CodeGenFunction &CGF, const Expr *e) { 1901 llvm::Value *value = CGF.EmitScalarExpr(e); 1902 return emitARCRetainAfterCall(CGF, value); 1903} 1904 1905static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF, 1906 llvm::Value *value) { 1907 if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) { 1908 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP(); 1909 1910 // Place the retain immediately following the call. 1911 CGF.Builder.SetInsertPoint(call->getParent(), 1912 ++llvm::BasicBlock::iterator(call)); 1913 value = CGF.EmitARCRetainAutoreleasedReturnValue(value); 1914 1915 CGF.Builder.restoreIP(ip); 1916 return value; 1917 } else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) { 1918 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP(); 1919 1920 // Place the retain at the beginning of the normal destination block. 1921 llvm::BasicBlock *BB = invoke->getNormalDest(); 1922 CGF.Builder.SetInsertPoint(BB, BB->begin()); 1923 value = CGF.EmitARCRetainAutoreleasedReturnValue(value); 1924 1925 CGF.Builder.restoreIP(ip); 1926 return value; 1927 1928 // Bitcasts can arise because of related-result returns. Rewrite 1929 // the operand. 1930 } else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) { 1931 llvm::Value *operand = bitcast->getOperand(0); 1932 operand = emitARCRetainAfterCall(CGF, operand); 1933 bitcast->setOperand(0, operand); 1934 return bitcast; 1935 1936 // Generic fall-back case. 1937 } else { 1938 // Retain using the non-block variant: we never need to do a copy 1939 // of a block that's been returned to us. 1940 return CGF.EmitARCRetainNonBlock(value); 1941 } 1942} 1943 1944static TryEmitResult 1945tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) { 1946 // Look through cleanups. 1947 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) { 1948 CodeGenFunction::RunCleanupsScope scope(CGF); 1949 return tryEmitARCRetainScalarExpr(CGF, cleanups->getSubExpr()); 1950 } 1951 1952 // The desired result type, if it differs from the type of the 1953 // ultimate opaque expression. 1954 llvm::Type *resultType = 0; 1955 1956 // If we're loading retained from a __strong xvalue, we can avoid 1957 // an extra retain/release pair by zeroing out the source of this 1958 // "move" operation. 1959 if (e->isXValue() && !e->getType().isConstQualified() && 1960 e->getType().getObjCLifetime() == Qualifiers::OCL_Strong) { 1961 // Emit the lvalue 1962 LValue lv = CGF.EmitLValue(e); 1963 1964 // Load the object pointer and cast it to the appropriate type. 1965 QualType exprType = e->getType(); 1966 llvm::Value *result = CGF.EmitLoadOfLValue(lv).getScalarVal(); 1967 1968 if (resultType) 1969 result = CGF.Builder.CreateBitCast(result, resultType); 1970 1971 // Set the source pointer to NULL. 1972 llvm::Value *null 1973 = llvm::ConstantPointerNull::get( 1974 cast<llvm::PointerType>(CGF.ConvertType(exprType))); 1975 CGF.EmitStoreOfScalar(null, lv); 1976 1977 return TryEmitResult(result, true); 1978 } 1979 1980 while (true) { 1981 e = e->IgnoreParens(); 1982 1983 // There's a break at the end of this if-chain; anything 1984 // that wants to keep looping has to explicitly continue. 1985 if (const CastExpr *ce = dyn_cast<CastExpr>(e)) { 1986 switch (ce->getCastKind()) { 1987 // No-op casts don't change the type, so we just ignore them. 1988 case CK_NoOp: 1989 e = ce->getSubExpr(); 1990 continue; 1991 1992 case CK_LValueToRValue: { 1993 TryEmitResult loadResult 1994 = tryEmitARCRetainLoadOfScalar(CGF, ce->getSubExpr()); 1995 if (resultType) { 1996 llvm::Value *value = loadResult.getPointer(); 1997 value = CGF.Builder.CreateBitCast(value, resultType); 1998 loadResult.setPointer(value); 1999 } 2000 return loadResult; 2001 } 2002 2003 // These casts can change the type, so remember that and 2004 // soldier on. We only need to remember the outermost such 2005 // cast, though. 2006 case CK_AnyPointerToObjCPointerCast: 2007 case CK_AnyPointerToBlockPointerCast: 2008 case CK_BitCast: 2009 if (!resultType) 2010 resultType = CGF.ConvertType(ce->getType()); 2011 e = ce->getSubExpr(); 2012 assert(e->getType()->hasPointerRepresentation()); 2013 continue; 2014 2015 // For consumptions, just emit the subexpression and thus elide 2016 // the retain/release pair. 2017 case CK_ObjCConsumeObject: { 2018 llvm::Value *result = CGF.EmitScalarExpr(ce->getSubExpr()); 2019 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType); 2020 return TryEmitResult(result, true); 2021 } 2022 2023 // For reclaims, emit the subexpression as a retained call and 2024 // skip the consumption. 2025 case CK_ObjCReclaimReturnedObject: { 2026 llvm::Value *result = emitARCRetainCall(CGF, ce->getSubExpr()); 2027 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType); 2028 return TryEmitResult(result, true); 2029 } 2030 2031 case CK_GetObjCProperty: { 2032 llvm::Value *result = emitARCRetainCall(CGF, ce); 2033 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType); 2034 return TryEmitResult(result, true); 2035 } 2036 2037 default: 2038 break; 2039 } 2040 2041 // Skip __extension__. 2042 } else if (const UnaryOperator *op = dyn_cast<UnaryOperator>(e)) { 2043 if (op->getOpcode() == UO_Extension) { 2044 e = op->getSubExpr(); 2045 continue; 2046 } 2047 2048 // For calls and message sends, use the retained-call logic. 2049 // Delegate inits are a special case in that they're the only 2050 // returns-retained expression that *isn't* surrounded by 2051 // a consume. 2052 } else if (isa<CallExpr>(e) || 2053 (isa<ObjCMessageExpr>(e) && 2054 !cast<ObjCMessageExpr>(e)->isDelegateInitCall())) { 2055 llvm::Value *result = emitARCRetainCall(CGF, e); 2056 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType); 2057 return TryEmitResult(result, true); 2058 } 2059 2060 // Conservatively halt the search at any other expression kind. 2061 break; 2062 } 2063 2064 // We didn't find an obvious production, so emit what we've got and 2065 // tell the caller that we didn't manage to retain. 2066 llvm::Value *result = CGF.EmitScalarExpr(e); 2067 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType); 2068 return TryEmitResult(result, false); 2069} 2070 2071static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF, 2072 LValue lvalue, 2073 QualType type) { 2074 TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type); 2075 llvm::Value *value = result.getPointer(); 2076 if (!result.getInt()) 2077 value = CGF.EmitARCRetain(type, value); 2078 return value; 2079} 2080 2081/// EmitARCRetainScalarExpr - Semantically equivalent to 2082/// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a 2083/// best-effort attempt to peephole expressions that naturally produce 2084/// retained objects. 2085llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) { 2086 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e); 2087 llvm::Value *value = result.getPointer(); 2088 if (!result.getInt()) 2089 value = EmitARCRetain(e->getType(), value); 2090 return value; 2091} 2092 2093llvm::Value * 2094CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) { 2095 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e); 2096 llvm::Value *value = result.getPointer(); 2097 if (result.getInt()) 2098 value = EmitARCAutorelease(value); 2099 else 2100 value = EmitARCRetainAutorelease(e->getType(), value); 2101 return value; 2102} 2103 2104std::pair<LValue,llvm::Value*> 2105CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e, 2106 bool ignored) { 2107 // Evaluate the RHS first. 2108 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS()); 2109 llvm::Value *value = result.getPointer(); 2110 2111 bool hasImmediateRetain = result.getInt(); 2112 2113 // If we didn't emit a retained object, and the l-value is of block 2114 // type, then we need to emit the block-retain immediately in case 2115 // it invalidates the l-value. 2116 if (!hasImmediateRetain && e->getType()->isBlockPointerType()) { 2117 value = EmitARCRetainBlock(value); 2118 hasImmediateRetain = true; 2119 } 2120 2121 LValue lvalue = EmitLValue(e->getLHS()); 2122 2123 // If the RHS was emitted retained, expand this. 2124 if (hasImmediateRetain) { 2125 llvm::Value *oldValue = 2126 EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatileQualified(), 2127 lvalue.getAlignment(), e->getType(), 2128 lvalue.getTBAAInfo()); 2129 EmitStoreOfScalar(value, lvalue.getAddress(), 2130 lvalue.isVolatileQualified(), lvalue.getAlignment(), 2131 e->getType(), lvalue.getTBAAInfo()); 2132 EmitARCRelease(oldValue, /*precise*/ false); 2133 } else { 2134 value = EmitARCStoreStrong(lvalue, value, ignored); 2135 } 2136 2137 return std::pair<LValue,llvm::Value*>(lvalue, value); 2138} 2139 2140std::pair<LValue,llvm::Value*> 2141CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) { 2142 llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS()); 2143 LValue lvalue = EmitLValue(e->getLHS()); 2144 2145 EmitStoreOfScalar(value, lvalue.getAddress(), 2146 lvalue.isVolatileQualified(), lvalue.getAlignment(), 2147 e->getType(), lvalue.getTBAAInfo()); 2148 2149 return std::pair<LValue,llvm::Value*>(lvalue, value); 2150} 2151 2152void CodeGenFunction::EmitObjCAutoreleasePoolStmt( 2153 const ObjCAutoreleasePoolStmt &ARPS) { 2154 const Stmt *subStmt = ARPS.getSubStmt(); 2155 const CompoundStmt &S = cast<CompoundStmt>(*subStmt); 2156 2157 CGDebugInfo *DI = getDebugInfo(); 2158 if (DI) { 2159 DI->setLocation(S.getLBracLoc()); 2160 DI->EmitRegionStart(Builder); 2161 } 2162 2163 // Keep track of the current cleanup stack depth. 2164 RunCleanupsScope Scope(*this); 2165 if (CGM.getCodeGenOpts().ObjCRuntimeHasARC) { 2166 llvm::Value *token = EmitObjCAutoreleasePoolPush(); 2167 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token); 2168 } else { 2169 llvm::Value *token = EmitObjCMRRAutoreleasePoolPush(); 2170 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token); 2171 } 2172 2173 for (CompoundStmt::const_body_iterator I = S.body_begin(), 2174 E = S.body_end(); I != E; ++I) 2175 EmitStmt(*I); 2176 2177 if (DI) { 2178 DI->setLocation(S.getRBracLoc()); 2179 DI->EmitRegionEnd(Builder); 2180 } 2181} 2182 2183/// EmitExtendGCLifetime - Given a pointer to an Objective-C object, 2184/// make sure it survives garbage collection until this point. 2185void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) { 2186 // We just use an inline assembly. 2187 llvm::FunctionType *extenderType 2188 = llvm::FunctionType::get(VoidTy, VoidPtrTy, /*variadic*/ false); 2189 llvm::Value *extender 2190 = llvm::InlineAsm::get(extenderType, 2191 /* assembly */ "", 2192 /* constraints */ "r", 2193 /* side effects */ true); 2194 2195 object = Builder.CreateBitCast(object, VoidPtrTy); 2196 Builder.CreateCall(extender, object)->setDoesNotThrow(); 2197} 2198 2199CGObjCRuntime::~CGObjCRuntime() {} 2200