1 //===--- CodeGenModule.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 coordinates the per-module state used while generating code. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "CodeGenModule.h" 15 #include "CGDebugInfo.h" 16 #include "CodeGenFunction.h" 17 #include "CGCall.h" 18 #include "CGObjCRuntime.h" 19 #include "Mangle.h" 20 #include "TargetInfo.h" 21 #include "clang/CodeGen/CodeGenOptions.h" 22 #include "clang/AST/ASTContext.h" 23 #include "clang/AST/CharUnits.h" 24 #include "clang/AST/DeclObjC.h" 25 #include "clang/AST/DeclCXX.h" 26 #include "clang/AST/RecordLayout.h" 27 #include "clang/Basic/Builtins.h" 28 #include "clang/Basic/Diagnostic.h" 29 #include "clang/Basic/SourceManager.h" 30 #include "clang/Basic/TargetInfo.h" 31 #include "clang/Basic/ConvertUTF.h" 32 #include "llvm/CallingConv.h" 33 #include "llvm/Module.h" 34 #include "llvm/Intrinsics.h" 35 #include "llvm/LLVMContext.h" 36 #include "llvm/Target/TargetData.h" 37 #include "llvm/Support/ErrorHandling.h" 38 using namespace clang; 39 using namespace CodeGen; 40 41 42 CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO, 43 llvm::Module &M, const llvm::TargetData &TD, 44 Diagnostic &diags) 45 : BlockModule(C, M, TD, Types, *this), Context(C), 46 Features(C.getLangOptions()), CodeGenOpts(CGO), TheModule(M), 47 TheTargetData(TD), TheTargetCodeGenInfo(0), Diags(diags), 48 Types(C, M, TD, getTargetCodeGenInfo().getABIInfo()), 49 MangleCtx(C), VtableInfo(*this), Runtime(0), 50 MemCpyFn(0), MemMoveFn(0), MemSetFn(0), CFConstantStringClassRef(0), 51 VMContext(M.getContext()) { 52 53 if (!Features.ObjC1) 54 Runtime = 0; 55 else if (!Features.NeXTRuntime) 56 Runtime = CreateGNUObjCRuntime(*this); 57 else if (Features.ObjCNonFragileABI) 58 Runtime = CreateMacNonFragileABIObjCRuntime(*this); 59 else 60 Runtime = CreateMacObjCRuntime(*this); 61 62 // If debug info generation is enabled, create the CGDebugInfo object. 63 DebugInfo = CodeGenOpts.DebugInfo ? new CGDebugInfo(*this) : 0; 64 } 65 66 CodeGenModule::~CodeGenModule() { 67 delete Runtime; 68 delete DebugInfo; 69 } 70 71 void CodeGenModule::createObjCRuntime() { 72 if (!Features.NeXTRuntime) 73 Runtime = CreateGNUObjCRuntime(*this); 74 else if (Features.ObjCNonFragileABI) 75 Runtime = CreateMacNonFragileABIObjCRuntime(*this); 76 else 77 Runtime = CreateMacObjCRuntime(*this); 78 } 79 80 void CodeGenModule::Release() { 81 EmitDeferred(); 82 EmitCXXGlobalInitFunc(); 83 if (Runtime) 84 if (llvm::Function *ObjCInitFunction = Runtime->ModuleInitFunction()) 85 AddGlobalCtor(ObjCInitFunction); 86 EmitCtorList(GlobalCtors, "llvm.global_ctors"); 87 EmitCtorList(GlobalDtors, "llvm.global_dtors"); 88 EmitAnnotations(); 89 EmitLLVMUsed(); 90 } 91 92 /// ErrorUnsupported - Print out an error that codegen doesn't support the 93 /// specified stmt yet. 94 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type, 95 bool OmitOnError) { 96 if (OmitOnError && getDiags().hasErrorOccurred()) 97 return; 98 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 99 "cannot compile this %0 yet"); 100 std::string Msg = Type; 101 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID) 102 << Msg << S->getSourceRange(); 103 } 104 105 /// ErrorUnsupported - Print out an error that codegen doesn't support the 106 /// specified decl yet. 107 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type, 108 bool OmitOnError) { 109 if (OmitOnError && getDiags().hasErrorOccurred()) 110 return; 111 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 112 "cannot compile this %0 yet"); 113 std::string Msg = Type; 114 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg; 115 } 116 117 LangOptions::VisibilityMode 118 CodeGenModule::getDeclVisibilityMode(const Decl *D) const { 119 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 120 if (VD->getStorageClass() == VarDecl::PrivateExtern) 121 return LangOptions::Hidden; 122 123 if (const VisibilityAttr *attr = D->getAttr<VisibilityAttr>()) { 124 switch (attr->getVisibility()) { 125 default: assert(0 && "Unknown visibility!"); 126 case VisibilityAttr::DefaultVisibility: 127 return LangOptions::Default; 128 case VisibilityAttr::HiddenVisibility: 129 return LangOptions::Hidden; 130 case VisibilityAttr::ProtectedVisibility: 131 return LangOptions::Protected; 132 } 133 } 134 135 return getLangOptions().getVisibilityMode(); 136 } 137 138 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV, 139 const Decl *D) const { 140 // Internal definitions always have default visibility. 141 if (GV->hasLocalLinkage()) { 142 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 143 return; 144 } 145 146 switch (getDeclVisibilityMode(D)) { 147 default: assert(0 && "Unknown visibility!"); 148 case LangOptions::Default: 149 return GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 150 case LangOptions::Hidden: 151 return GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 152 case LangOptions::Protected: 153 return GV->setVisibility(llvm::GlobalValue::ProtectedVisibility); 154 } 155 } 156 157 const char *CodeGenModule::getMangledName(const GlobalDecl &GD) { 158 const NamedDecl *ND = cast<NamedDecl>(GD.getDecl()); 159 160 if (const CXXConstructorDecl *D = dyn_cast<CXXConstructorDecl>(ND)) 161 return getMangledCXXCtorName(D, GD.getCtorType()); 162 if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND)) 163 return getMangledCXXDtorName(D, GD.getDtorType()); 164 165 return getMangledName(ND); 166 } 167 168 /// \brief Retrieves the mangled name for the given declaration. 169 /// 170 /// If the given declaration requires a mangled name, returns an 171 /// const char* containing the mangled name. Otherwise, returns 172 /// the unmangled name. 173 /// 174 const char *CodeGenModule::getMangledName(const NamedDecl *ND) { 175 if (!getMangleContext().shouldMangleDeclName(ND)) { 176 assert(ND->getIdentifier() && "Attempt to mangle unnamed decl."); 177 return ND->getNameAsCString(); 178 } 179 180 llvm::SmallString<256> Name; 181 getMangleContext().mangleName(ND, Name); 182 Name += '\0'; 183 return UniqueMangledName(Name.begin(), Name.end()); 184 } 185 186 const char *CodeGenModule::UniqueMangledName(const char *NameStart, 187 const char *NameEnd) { 188 assert(*(NameEnd - 1) == '\0' && "Mangled name must be null terminated!"); 189 190 return MangledNames.GetOrCreateValue(NameStart, NameEnd).getKeyData(); 191 } 192 193 /// AddGlobalCtor - Add a function to the list that will be called before 194 /// main() runs. 195 void CodeGenModule::AddGlobalCtor(llvm::Function * Ctor, int Priority) { 196 // FIXME: Type coercion of void()* types. 197 GlobalCtors.push_back(std::make_pair(Ctor, Priority)); 198 } 199 200 /// AddGlobalDtor - Add a function to the list that will be called 201 /// when the module is unloaded. 202 void CodeGenModule::AddGlobalDtor(llvm::Function * Dtor, int Priority) { 203 // FIXME: Type coercion of void()* types. 204 GlobalDtors.push_back(std::make_pair(Dtor, Priority)); 205 } 206 207 void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) { 208 // Ctor function type is void()*. 209 llvm::FunctionType* CtorFTy = 210 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 211 std::vector<const llvm::Type*>(), 212 false); 213 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy); 214 215 // Get the type of a ctor entry, { i32, void ()* }. 216 llvm::StructType* CtorStructTy = 217 llvm::StructType::get(VMContext, llvm::Type::getInt32Ty(VMContext), 218 llvm::PointerType::getUnqual(CtorFTy), NULL); 219 220 // Construct the constructor and destructor arrays. 221 std::vector<llvm::Constant*> Ctors; 222 for (CtorList::const_iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 223 std::vector<llvm::Constant*> S; 224 S.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 225 I->second, false)); 226 S.push_back(llvm::ConstantExpr::getBitCast(I->first, CtorPFTy)); 227 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S)); 228 } 229 230 if (!Ctors.empty()) { 231 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size()); 232 new llvm::GlobalVariable(TheModule, AT, false, 233 llvm::GlobalValue::AppendingLinkage, 234 llvm::ConstantArray::get(AT, Ctors), 235 GlobalName); 236 } 237 } 238 239 void CodeGenModule::EmitAnnotations() { 240 if (Annotations.empty()) 241 return; 242 243 // Create a new global variable for the ConstantStruct in the Module. 244 llvm::Constant *Array = 245 llvm::ConstantArray::get(llvm::ArrayType::get(Annotations[0]->getType(), 246 Annotations.size()), 247 Annotations); 248 llvm::GlobalValue *gv = 249 new llvm::GlobalVariable(TheModule, Array->getType(), false, 250 llvm::GlobalValue::AppendingLinkage, Array, 251 "llvm.global.annotations"); 252 gv->setSection("llvm.metadata"); 253 } 254 255 static CodeGenModule::GVALinkage 256 GetLinkageForFunction(ASTContext &Context, const FunctionDecl *FD, 257 const LangOptions &Features) { 258 CodeGenModule::GVALinkage External = CodeGenModule::GVA_StrongExternal; 259 260 Linkage L = FD->getLinkage(); 261 if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus && 262 FD->getType()->getLinkage() == UniqueExternalLinkage) 263 L = UniqueExternalLinkage; 264 265 switch (L) { 266 case NoLinkage: 267 case InternalLinkage: 268 case UniqueExternalLinkage: 269 return CodeGenModule::GVA_Internal; 270 271 case ExternalLinkage: 272 switch (FD->getTemplateSpecializationKind()) { 273 case TSK_Undeclared: 274 case TSK_ExplicitSpecialization: 275 External = CodeGenModule::GVA_StrongExternal; 276 break; 277 278 case TSK_ExplicitInstantiationDefinition: 279 // FIXME: explicit instantiation definitions should use weak linkage 280 return CodeGenModule::GVA_StrongExternal; 281 282 case TSK_ExplicitInstantiationDeclaration: 283 case TSK_ImplicitInstantiation: 284 External = CodeGenModule::GVA_TemplateInstantiation; 285 break; 286 } 287 } 288 289 if (!FD->isInlined()) 290 return External; 291 292 if (!Features.CPlusPlus || FD->hasAttr<GNUInlineAttr>()) { 293 // GNU or C99 inline semantics. Determine whether this symbol should be 294 // externally visible. 295 if (FD->isInlineDefinitionExternallyVisible()) 296 return External; 297 298 // C99 inline semantics, where the symbol is not externally visible. 299 return CodeGenModule::GVA_C99Inline; 300 } 301 302 // C++0x [temp.explicit]p9: 303 // [ Note: The intent is that an inline function that is the subject of 304 // an explicit instantiation declaration will still be implicitly 305 // instantiated when used so that the body can be considered for 306 // inlining, but that no out-of-line copy of the inline function would be 307 // generated in the translation unit. -- end note ] 308 if (FD->getTemplateSpecializationKind() 309 == TSK_ExplicitInstantiationDeclaration) 310 return CodeGenModule::GVA_C99Inline; 311 312 return CodeGenModule::GVA_CXXInline; 313 } 314 315 /// SetFunctionDefinitionAttributes - Set attributes for a global. 316 /// 317 /// FIXME: This is currently only done for aliases and functions, but not for 318 /// variables (these details are set in EmitGlobalVarDefinition for variables). 319 void CodeGenModule::SetFunctionDefinitionAttributes(const FunctionDecl *D, 320 llvm::GlobalValue *GV) { 321 GVALinkage Linkage = GetLinkageForFunction(getContext(), D, Features); 322 323 if (Linkage == GVA_Internal) { 324 GV->setLinkage(llvm::Function::InternalLinkage); 325 } else if (D->hasAttr<DLLExportAttr>()) { 326 GV->setLinkage(llvm::Function::DLLExportLinkage); 327 } else if (D->hasAttr<WeakAttr>()) { 328 GV->setLinkage(llvm::Function::WeakAnyLinkage); 329 } else if (Linkage == GVA_C99Inline) { 330 // In C99 mode, 'inline' functions are guaranteed to have a strong 331 // definition somewhere else, so we can use available_externally linkage. 332 GV->setLinkage(llvm::Function::AvailableExternallyLinkage); 333 } else if (Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation) { 334 // In C++, the compiler has to emit a definition in every translation unit 335 // that references the function. We should use linkonce_odr because 336 // a) if all references in this translation unit are optimized away, we 337 // don't need to codegen it. b) if the function persists, it needs to be 338 // merged with other definitions. c) C++ has the ODR, so we know the 339 // definition is dependable. 340 GV->setLinkage(llvm::Function::LinkOnceODRLinkage); 341 } else { 342 assert(Linkage == GVA_StrongExternal); 343 // Otherwise, we have strong external linkage. 344 GV->setLinkage(llvm::Function::ExternalLinkage); 345 } 346 347 SetCommonAttributes(D, GV); 348 } 349 350 void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D, 351 const CGFunctionInfo &Info, 352 llvm::Function *F) { 353 unsigned CallingConv; 354 AttributeListType AttributeList; 355 ConstructAttributeList(Info, D, AttributeList, CallingConv); 356 F->setAttributes(llvm::AttrListPtr::get(AttributeList.begin(), 357 AttributeList.size())); 358 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 359 } 360 361 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 362 llvm::Function *F) { 363 if (!Features.Exceptions && !Features.ObjCNonFragileABI) 364 F->addFnAttr(llvm::Attribute::NoUnwind); 365 366 if (D->hasAttr<AlwaysInlineAttr>()) 367 F->addFnAttr(llvm::Attribute::AlwaysInline); 368 369 if (D->hasAttr<NoInlineAttr>()) 370 F->addFnAttr(llvm::Attribute::NoInline); 371 372 if (Features.getStackProtectorMode() == LangOptions::SSPOn) 373 F->addFnAttr(llvm::Attribute::StackProtect); 374 else if (Features.getStackProtectorMode() == LangOptions::SSPReq) 375 F->addFnAttr(llvm::Attribute::StackProtectReq); 376 377 if (const AlignedAttr *AA = D->getAttr<AlignedAttr>()) { 378 unsigned width = Context.Target.getCharWidth(); 379 F->setAlignment(AA->getAlignment() / width); 380 while ((AA = AA->getNext<AlignedAttr>())) 381 F->setAlignment(std::max(F->getAlignment(), AA->getAlignment() / width)); 382 } 383 // C++ ABI requires 2-byte alignment for member functions. 384 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D)) 385 F->setAlignment(2); 386 } 387 388 void CodeGenModule::SetCommonAttributes(const Decl *D, 389 llvm::GlobalValue *GV) { 390 setGlobalVisibility(GV, D); 391 392 if (D->hasAttr<UsedAttr>()) 393 AddUsedGlobal(GV); 394 395 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 396 GV->setSection(SA->getName()); 397 398 getTargetCodeGenInfo().SetTargetAttributes(D, GV, *this); 399 } 400 401 void CodeGenModule::SetInternalFunctionAttributes(const Decl *D, 402 llvm::Function *F, 403 const CGFunctionInfo &FI) { 404 SetLLVMFunctionAttributes(D, FI, F); 405 SetLLVMFunctionAttributesForDefinition(D, F); 406 407 F->setLinkage(llvm::Function::InternalLinkage); 408 409 SetCommonAttributes(D, F); 410 } 411 412 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, 413 llvm::Function *F, 414 bool IsIncompleteFunction) { 415 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 416 417 if (!IsIncompleteFunction) 418 SetLLVMFunctionAttributes(FD, getTypes().getFunctionInfo(GD), F); 419 420 // Only a few attributes are set on declarations; these may later be 421 // overridden by a definition. 422 423 if (FD->hasAttr<DLLImportAttr>()) { 424 F->setLinkage(llvm::Function::DLLImportLinkage); 425 } else if (FD->hasAttr<WeakAttr>() || 426 FD->hasAttr<WeakImportAttr>()) { 427 // "extern_weak" is overloaded in LLVM; we probably should have 428 // separate linkage types for this. 429 F->setLinkage(llvm::Function::ExternalWeakLinkage); 430 } else { 431 F->setLinkage(llvm::Function::ExternalLinkage); 432 } 433 434 if (const SectionAttr *SA = FD->getAttr<SectionAttr>()) 435 F->setSection(SA->getName()); 436 } 437 438 void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) { 439 assert(!GV->isDeclaration() && 440 "Only globals with definition can force usage."); 441 LLVMUsed.push_back(GV); 442 } 443 444 void CodeGenModule::EmitLLVMUsed() { 445 // Don't create llvm.used if there is no need. 446 if (LLVMUsed.empty()) 447 return; 448 449 const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext); 450 451 // Convert LLVMUsed to what ConstantArray needs. 452 std::vector<llvm::Constant*> UsedArray; 453 UsedArray.resize(LLVMUsed.size()); 454 for (unsigned i = 0, e = LLVMUsed.size(); i != e; ++i) { 455 UsedArray[i] = 456 llvm::ConstantExpr::getBitCast(cast<llvm::Constant>(&*LLVMUsed[i]), 457 i8PTy); 458 } 459 460 if (UsedArray.empty()) 461 return; 462 llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, UsedArray.size()); 463 464 llvm::GlobalVariable *GV = 465 new llvm::GlobalVariable(getModule(), ATy, false, 466 llvm::GlobalValue::AppendingLinkage, 467 llvm::ConstantArray::get(ATy, UsedArray), 468 "llvm.used"); 469 470 GV->setSection("llvm.metadata"); 471 } 472 473 void CodeGenModule::EmitDeferred() { 474 // Emit code for any potentially referenced deferred decls. Since a 475 // previously unused static decl may become used during the generation of code 476 // for a static function, iterate until no changes are made. 477 while (!DeferredDeclsToEmit.empty()) { 478 GlobalDecl D = DeferredDeclsToEmit.back(); 479 DeferredDeclsToEmit.pop_back(); 480 481 // The mangled name for the decl must have been emitted in GlobalDeclMap. 482 // Look it up to see if it was defined with a stronger definition (e.g. an 483 // extern inline function with a strong function redefinition). If so, 484 // just ignore the deferred decl. 485 llvm::GlobalValue *CGRef = GlobalDeclMap[getMangledName(D)]; 486 assert(CGRef && "Deferred decl wasn't referenced?"); 487 488 if (!CGRef->isDeclaration()) 489 continue; 490 491 // Otherwise, emit the definition and move on to the next one. 492 EmitGlobalDefinition(D); 493 } 494 } 495 496 /// EmitAnnotateAttr - Generate the llvm::ConstantStruct which contains the 497 /// annotation information for a given GlobalValue. The annotation struct is 498 /// {i8 *, i8 *, i8 *, i32}. The first field is a constant expression, the 499 /// GlobalValue being annotated. The second field is the constant string 500 /// created from the AnnotateAttr's annotation. The third field is a constant 501 /// string containing the name of the translation unit. The fourth field is 502 /// the line number in the file of the annotated value declaration. 503 /// 504 /// FIXME: this does not unique the annotation string constants, as llvm-gcc 505 /// appears to. 506 /// 507 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 508 const AnnotateAttr *AA, 509 unsigned LineNo) { 510 llvm::Module *M = &getModule(); 511 512 // get [N x i8] constants for the annotation string, and the filename string 513 // which are the 2nd and 3rd elements of the global annotation structure. 514 const llvm::Type *SBP = llvm::Type::getInt8PtrTy(VMContext); 515 llvm::Constant *anno = llvm::ConstantArray::get(VMContext, 516 AA->getAnnotation(), true); 517 llvm::Constant *unit = llvm::ConstantArray::get(VMContext, 518 M->getModuleIdentifier(), 519 true); 520 521 // Get the two global values corresponding to the ConstantArrays we just 522 // created to hold the bytes of the strings. 523 llvm::GlobalValue *annoGV = 524 new llvm::GlobalVariable(*M, anno->getType(), false, 525 llvm::GlobalValue::PrivateLinkage, anno, 526 GV->getName()); 527 // translation unit name string, emitted into the llvm.metadata section. 528 llvm::GlobalValue *unitGV = 529 new llvm::GlobalVariable(*M, unit->getType(), false, 530 llvm::GlobalValue::PrivateLinkage, unit, 531 ".str"); 532 533 // Create the ConstantStruct for the global annotation. 534 llvm::Constant *Fields[4] = { 535 llvm::ConstantExpr::getBitCast(GV, SBP), 536 llvm::ConstantExpr::getBitCast(annoGV, SBP), 537 llvm::ConstantExpr::getBitCast(unitGV, SBP), 538 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), LineNo) 539 }; 540 return llvm::ConstantStruct::get(VMContext, Fields, 4, false); 541 } 542 543 bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) { 544 // Never defer when EmitAllDecls is specified or the decl has 545 // attribute used. 546 if (Features.EmitAllDecls || Global->hasAttr<UsedAttr>()) 547 return false; 548 549 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) { 550 // Constructors and destructors should never be deferred. 551 if (FD->hasAttr<ConstructorAttr>() || 552 FD->hasAttr<DestructorAttr>()) 553 return false; 554 555 // The key function for a class must never be deferred. 556 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Global)) { 557 const CXXRecordDecl *RD = MD->getParent(); 558 if (MD->isOutOfLine() && RD->isDynamicClass()) { 559 const CXXMethodDecl *KeyFunction = getContext().getKeyFunction(RD); 560 if (KeyFunction && 561 KeyFunction->getCanonicalDecl() == MD->getCanonicalDecl()) 562 return false; 563 } 564 } 565 566 GVALinkage Linkage = GetLinkageForFunction(getContext(), FD, Features); 567 568 // static, static inline, always_inline, and extern inline functions can 569 // always be deferred. Normal inline functions can be deferred in C99/C++. 570 if (Linkage == GVA_Internal || Linkage == GVA_C99Inline || 571 Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation) 572 return true; 573 return false; 574 } 575 576 const VarDecl *VD = cast<VarDecl>(Global); 577 assert(VD->isFileVarDecl() && "Invalid decl"); 578 579 // We never want to defer structs that have non-trivial constructors or 580 // destructors. 581 582 // FIXME: Handle references. 583 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 584 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 585 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) 586 return false; 587 } 588 } 589 590 // Static data may be deferred, but out-of-line static data members 591 // cannot be. 592 Linkage L = VD->getLinkage(); 593 if (L == ExternalLinkage && getContext().getLangOptions().CPlusPlus && 594 VD->getType()->getLinkage() == UniqueExternalLinkage) 595 L = UniqueExternalLinkage; 596 597 switch (L) { 598 case NoLinkage: 599 case InternalLinkage: 600 case UniqueExternalLinkage: 601 // Initializer has side effects? 602 if (VD->getInit() && VD->getInit()->HasSideEffects(Context)) 603 return false; 604 return !(VD->isStaticDataMember() && VD->isOutOfLine()); 605 606 case ExternalLinkage: 607 break; 608 } 609 610 return false; 611 } 612 613 void CodeGenModule::EmitGlobal(GlobalDecl GD) { 614 const ValueDecl *Global = cast<ValueDecl>(GD.getDecl()); 615 616 // If this is an alias definition (which otherwise looks like a declaration) 617 // emit it now. 618 if (Global->hasAttr<AliasAttr>()) 619 return EmitAliasDefinition(Global); 620 621 // Ignore declarations, they will be emitted on their first use. 622 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) { 623 // Forward declarations are emitted lazily on first use. 624 if (!FD->isThisDeclarationADefinition()) 625 return; 626 } else { 627 const VarDecl *VD = cast<VarDecl>(Global); 628 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 629 630 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) 631 return; 632 } 633 634 // Defer code generation when possible if this is a static definition, inline 635 // function etc. These we only want to emit if they are used. 636 if (MayDeferGeneration(Global)) { 637 // If the value has already been used, add it directly to the 638 // DeferredDeclsToEmit list. 639 const char *MangledName = getMangledName(GD); 640 if (GlobalDeclMap.count(MangledName)) 641 DeferredDeclsToEmit.push_back(GD); 642 else { 643 // Otherwise, remember that we saw a deferred decl with this name. The 644 // first use of the mangled name will cause it to move into 645 // DeferredDeclsToEmit. 646 DeferredDecls[MangledName] = GD; 647 } 648 return; 649 } 650 651 // Otherwise emit the definition. 652 EmitGlobalDefinition(GD); 653 } 654 655 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) { 656 const ValueDecl *D = cast<ValueDecl>(GD.getDecl()); 657 658 PrettyStackTraceDecl CrashInfo((ValueDecl *)D, D->getLocation(), 659 Context.getSourceManager(), 660 "Generating code for declaration"); 661 662 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 663 getVtableInfo().MaybeEmitVtable(GD); 664 if (MD->isVirtual() && MD->isOutOfLine() && 665 (!isa<CXXDestructorDecl>(D) || GD.getDtorType() != Dtor_Base)) { 666 if (isa<CXXDestructorDecl>(D)) { 667 GlobalDecl CanonGD(cast<CXXDestructorDecl>(D->getCanonicalDecl()), 668 GD.getDtorType()); 669 BuildThunksForVirtual(CanonGD); 670 } else { 671 BuildThunksForVirtual(MD->getCanonicalDecl()); 672 } 673 } 674 } 675 676 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 677 EmitCXXConstructor(CD, GD.getCtorType()); 678 else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(D)) 679 EmitCXXDestructor(DD, GD.getDtorType()); 680 else if (isa<FunctionDecl>(D)) 681 EmitGlobalFunctionDefinition(GD); 682 else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 683 EmitGlobalVarDefinition(VD); 684 else { 685 assert(0 && "Invalid argument to EmitGlobalDefinition()"); 686 } 687 } 688 689 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the 690 /// module, create and return an llvm Function with the specified type. If there 691 /// is something in the module with the specified name, return it potentially 692 /// bitcasted to the right type. 693 /// 694 /// If D is non-null, it specifies a decl that correspond to this. This is used 695 /// to set the attributes on the function when it is first created. 696 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(const char *MangledName, 697 const llvm::Type *Ty, 698 GlobalDecl D) { 699 // Lookup the entry, lazily creating it if necessary. 700 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 701 if (Entry) { 702 if (Entry->getType()->getElementType() == Ty) 703 return Entry; 704 705 // Make sure the result is of the correct type. 706 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 707 return llvm::ConstantExpr::getBitCast(Entry, PTy); 708 } 709 710 // This function doesn't have a complete type (for example, the return 711 // type is an incomplete struct). Use a fake type instead, and make 712 // sure not to try to set attributes. 713 bool IsIncompleteFunction = false; 714 if (!isa<llvm::FunctionType>(Ty)) { 715 Ty = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 716 std::vector<const llvm::Type*>(), false); 717 IsIncompleteFunction = true; 718 } 719 llvm::Function *F = llvm::Function::Create(cast<llvm::FunctionType>(Ty), 720 llvm::Function::ExternalLinkage, 721 "", &getModule()); 722 F->setName(MangledName); 723 if (D.getDecl()) 724 SetFunctionAttributes(D, F, IsIncompleteFunction); 725 Entry = F; 726 727 // This is the first use or definition of a mangled name. If there is a 728 // deferred decl with this name, remember that we need to emit it at the end 729 // of the file. 730 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 731 DeferredDecls.find(MangledName); 732 if (DDI != DeferredDecls.end()) { 733 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 734 // list, and remove it from DeferredDecls (since we don't need it anymore). 735 DeferredDeclsToEmit.push_back(DDI->second); 736 DeferredDecls.erase(DDI); 737 } else if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl())) { 738 // If this the first reference to a C++ inline function in a class, queue up 739 // the deferred function body for emission. These are not seen as 740 // top-level declarations. 741 if (FD->isThisDeclarationADefinition() && MayDeferGeneration(FD)) 742 DeferredDeclsToEmit.push_back(D); 743 // A called constructor which has no definition or declaration need be 744 // synthesized. 745 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) { 746 if (CD->isImplicit()) 747 DeferredDeclsToEmit.push_back(D); 748 } else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD)) { 749 if (DD->isImplicit()) 750 DeferredDeclsToEmit.push_back(D); 751 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 752 if (MD->isCopyAssignment() && MD->isImplicit()) 753 DeferredDeclsToEmit.push_back(D); 754 } 755 } 756 757 return F; 758 } 759 760 /// GetAddrOfFunction - Return the address of the given function. If Ty is 761 /// non-null, then this function will use the specified type if it has to 762 /// create it (this occurs when we see a definition of the function). 763 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD, 764 const llvm::Type *Ty) { 765 // If there was no specific requested type, just convert it now. 766 if (!Ty) 767 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType()); 768 return GetOrCreateLLVMFunction(getMangledName(GD), Ty, GD); 769 } 770 771 /// CreateRuntimeFunction - Create a new runtime function with the specified 772 /// type and name. 773 llvm::Constant * 774 CodeGenModule::CreateRuntimeFunction(const llvm::FunctionType *FTy, 775 const char *Name) { 776 // Convert Name to be a uniqued string from the IdentifierInfo table. 777 Name = getContext().Idents.get(Name).getNameStart(); 778 return GetOrCreateLLVMFunction(Name, FTy, GlobalDecl()); 779 } 780 781 static bool DeclIsConstantGlobal(ASTContext &Context, const VarDecl *D) { 782 if (!D->getType().isConstant(Context)) 783 return false; 784 if (Context.getLangOptions().CPlusPlus && 785 Context.getBaseElementType(D->getType())->getAs<RecordType>()) { 786 // FIXME: We should do something fancier here! 787 return false; 788 } 789 return true; 790 } 791 792 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 793 /// create and return an llvm GlobalVariable with the specified type. If there 794 /// is something in the module with the specified name, return it potentially 795 /// bitcasted to the right type. 796 /// 797 /// If D is non-null, it specifies a decl that correspond to this. This is used 798 /// to set the attributes on the global when it is first created. 799 llvm::Constant *CodeGenModule::GetOrCreateLLVMGlobal(const char *MangledName, 800 const llvm::PointerType*Ty, 801 const VarDecl *D) { 802 // Lookup the entry, lazily creating it if necessary. 803 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 804 if (Entry) { 805 if (Entry->getType() == Ty) 806 return Entry; 807 808 // Make sure the result is of the correct type. 809 return llvm::ConstantExpr::getBitCast(Entry, Ty); 810 } 811 812 // This is the first use or definition of a mangled name. If there is a 813 // deferred decl with this name, remember that we need to emit it at the end 814 // of the file. 815 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 816 DeferredDecls.find(MangledName); 817 if (DDI != DeferredDecls.end()) { 818 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 819 // list, and remove it from DeferredDecls (since we don't need it anymore). 820 DeferredDeclsToEmit.push_back(DDI->second); 821 DeferredDecls.erase(DDI); 822 } 823 824 llvm::GlobalVariable *GV = 825 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false, 826 llvm::GlobalValue::ExternalLinkage, 827 0, "", 0, 828 false, Ty->getAddressSpace()); 829 GV->setName(MangledName); 830 831 // Handle things which are present even on external declarations. 832 if (D) { 833 // FIXME: This code is overly simple and should be merged with other global 834 // handling. 835 GV->setConstant(DeclIsConstantGlobal(Context, D)); 836 837 // FIXME: Merge with other attribute handling code. 838 if (D->getStorageClass() == VarDecl::PrivateExtern) 839 GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 840 841 if (D->hasAttr<WeakAttr>() || 842 D->hasAttr<WeakImportAttr>()) 843 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 844 845 GV->setThreadLocal(D->isThreadSpecified()); 846 } 847 848 return Entry = GV; 849 } 850 851 852 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 853 /// given global variable. If Ty is non-null and if the global doesn't exist, 854 /// then it will be greated with the specified type instead of whatever the 855 /// normal requested type would be. 856 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 857 const llvm::Type *Ty) { 858 assert(D->hasGlobalStorage() && "Not a global variable"); 859 QualType ASTTy = D->getType(); 860 if (Ty == 0) 861 Ty = getTypes().ConvertTypeForMem(ASTTy); 862 863 const llvm::PointerType *PTy = 864 llvm::PointerType::get(Ty, ASTTy.getAddressSpace()); 865 return GetOrCreateLLVMGlobal(getMangledName(D), PTy, D); 866 } 867 868 /// CreateRuntimeVariable - Create a new runtime global variable with the 869 /// specified type and name. 870 llvm::Constant * 871 CodeGenModule::CreateRuntimeVariable(const llvm::Type *Ty, 872 const char *Name) { 873 // Convert Name to be a uniqued string from the IdentifierInfo table. 874 Name = getContext().Idents.get(Name).getNameStart(); 875 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0); 876 } 877 878 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 879 assert(!D->getInit() && "Cannot emit definite definitions here!"); 880 881 if (MayDeferGeneration(D)) { 882 // If we have not seen a reference to this variable yet, place it 883 // into the deferred declarations table to be emitted if needed 884 // later. 885 const char *MangledName = getMangledName(D); 886 if (GlobalDeclMap.count(MangledName) == 0) { 887 DeferredDecls[MangledName] = D; 888 return; 889 } 890 } 891 892 // The tentative definition is the only definition. 893 EmitGlobalVarDefinition(D); 894 } 895 896 llvm::GlobalVariable::LinkageTypes 897 CodeGenModule::getVtableLinkage(const CXXRecordDecl *RD) { 898 if (RD->isInAnonymousNamespace() || !RD->hasLinkage()) 899 return llvm::GlobalVariable::InternalLinkage; 900 901 if (const CXXMethodDecl *KeyFunction 902 = RD->getASTContext().getKeyFunction(RD)) { 903 // If this class has a key function, use that to determine the linkage of 904 // the vtable. 905 const FunctionDecl *Def = 0; 906 if (KeyFunction->getBody(Def)) 907 KeyFunction = cast<CXXMethodDecl>(Def); 908 909 switch (KeyFunction->getTemplateSpecializationKind()) { 910 case TSK_Undeclared: 911 case TSK_ExplicitSpecialization: 912 if (KeyFunction->isInlined()) 913 return llvm::GlobalVariable::WeakODRLinkage; 914 915 return llvm::GlobalVariable::ExternalLinkage; 916 917 case TSK_ImplicitInstantiation: 918 case TSK_ExplicitInstantiationDefinition: 919 return llvm::GlobalVariable::WeakODRLinkage; 920 921 case TSK_ExplicitInstantiationDeclaration: 922 // FIXME: Use available_externally linkage. However, this currently 923 // breaks LLVM's build due to undefined symbols. 924 // return llvm::GlobalVariable::AvailableExternallyLinkage; 925 return llvm::GlobalVariable::WeakODRLinkage; 926 } 927 } 928 929 switch (RD->getTemplateSpecializationKind()) { 930 case TSK_Undeclared: 931 case TSK_ExplicitSpecialization: 932 case TSK_ImplicitInstantiation: 933 case TSK_ExplicitInstantiationDefinition: 934 return llvm::GlobalVariable::WeakODRLinkage; 935 936 case TSK_ExplicitInstantiationDeclaration: 937 // FIXME: Use available_externally linkage. However, this currently 938 // breaks LLVM's build due to undefined symbols. 939 // return llvm::GlobalVariable::AvailableExternallyLinkage; 940 return llvm::GlobalVariable::WeakODRLinkage; 941 } 942 943 // Silence GCC warning. 944 return llvm::GlobalVariable::WeakODRLinkage; 945 } 946 947 static CodeGenModule::GVALinkage 948 GetLinkageForVariable(ASTContext &Context, const VarDecl *VD) { 949 // If this is a static data member, compute the kind of template 950 // specialization. Otherwise, this variable is not part of a 951 // template. 952 TemplateSpecializationKind TSK = TSK_Undeclared; 953 if (VD->isStaticDataMember()) 954 TSK = VD->getTemplateSpecializationKind(); 955 956 Linkage L = VD->getLinkage(); 957 if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus && 958 VD->getType()->getLinkage() == UniqueExternalLinkage) 959 L = UniqueExternalLinkage; 960 961 switch (L) { 962 case NoLinkage: 963 case InternalLinkage: 964 case UniqueExternalLinkage: 965 return CodeGenModule::GVA_Internal; 966 967 case ExternalLinkage: 968 switch (TSK) { 969 case TSK_Undeclared: 970 case TSK_ExplicitSpecialization: 971 972 // FIXME: ExplicitInstantiationDefinition should be weak! 973 case TSK_ExplicitInstantiationDefinition: 974 return CodeGenModule::GVA_StrongExternal; 975 976 case TSK_ExplicitInstantiationDeclaration: 977 llvm_unreachable("Variable should not be instantiated"); 978 // Fall through to treat this like any other instantiation. 979 980 case TSK_ImplicitInstantiation: 981 return CodeGenModule::GVA_TemplateInstantiation; 982 } 983 } 984 985 return CodeGenModule::GVA_StrongExternal; 986 } 987 988 CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const { 989 return CharUnits::fromQuantity( 990 TheTargetData.getTypeStoreSizeInBits(Ty) / Context.getCharWidth()); 991 } 992 993 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { 994 llvm::Constant *Init = 0; 995 QualType ASTTy = D->getType(); 996 bool NonConstInit = false; 997 998 const Expr *InitExpr = D->getAnyInitializer(); 999 1000 if (!InitExpr) { 1001 // This is a tentative definition; tentative definitions are 1002 // implicitly initialized with { 0 }. 1003 // 1004 // Note that tentative definitions are only emitted at the end of 1005 // a translation unit, so they should never have incomplete 1006 // type. In addition, EmitTentativeDefinition makes sure that we 1007 // never attempt to emit a tentative definition if a real one 1008 // exists. A use may still exists, however, so we still may need 1009 // to do a RAUW. 1010 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 1011 Init = EmitNullConstant(D->getType()); 1012 } else { 1013 Init = EmitConstantExpr(InitExpr, D->getType()); 1014 1015 if (!Init) { 1016 QualType T = InitExpr->getType(); 1017 if (getLangOptions().CPlusPlus) { 1018 EmitCXXGlobalVarDeclInitFunc(D); 1019 Init = EmitNullConstant(T); 1020 NonConstInit = true; 1021 } else { 1022 ErrorUnsupported(D, "static initializer"); 1023 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 1024 } 1025 } 1026 } 1027 1028 const llvm::Type* InitType = Init->getType(); 1029 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType); 1030 1031 // Strip off a bitcast if we got one back. 1032 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1033 assert(CE->getOpcode() == llvm::Instruction::BitCast || 1034 // all zero index gep. 1035 CE->getOpcode() == llvm::Instruction::GetElementPtr); 1036 Entry = CE->getOperand(0); 1037 } 1038 1039 // Entry is now either a Function or GlobalVariable. 1040 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry); 1041 1042 // We have a definition after a declaration with the wrong type. 1043 // We must make a new GlobalVariable* and update everything that used OldGV 1044 // (a declaration or tentative definition) with the new GlobalVariable* 1045 // (which will be a definition). 1046 // 1047 // This happens if there is a prototype for a global (e.g. 1048 // "extern int x[];") and then a definition of a different type (e.g. 1049 // "int x[10];"). This also happens when an initializer has a different type 1050 // from the type of the global (this happens with unions). 1051 if (GV == 0 || 1052 GV->getType()->getElementType() != InitType || 1053 GV->getType()->getAddressSpace() != ASTTy.getAddressSpace()) { 1054 1055 // Remove the old entry from GlobalDeclMap so that we'll create a new one. 1056 GlobalDeclMap.erase(getMangledName(D)); 1057 1058 // Make a new global with the correct type, this is now guaranteed to work. 1059 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType)); 1060 GV->takeName(cast<llvm::GlobalValue>(Entry)); 1061 1062 // Replace all uses of the old global with the new global 1063 llvm::Constant *NewPtrForOldDecl = 1064 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 1065 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1066 1067 // Erase the old global, since it is no longer used. 1068 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 1069 } 1070 1071 if (const AnnotateAttr *AA = D->getAttr<AnnotateAttr>()) { 1072 SourceManager &SM = Context.getSourceManager(); 1073 AddAnnotation(EmitAnnotateAttr(GV, AA, 1074 SM.getInstantiationLineNumber(D->getLocation()))); 1075 } 1076 1077 GV->setInitializer(Init); 1078 1079 // If it is safe to mark the global 'constant', do so now. 1080 GV->setConstant(false); 1081 if (!NonConstInit && DeclIsConstantGlobal(Context, D)) 1082 GV->setConstant(true); 1083 1084 GV->setAlignment(getContext().getDeclAlign(D).getQuantity()); 1085 1086 // Set the llvm linkage type as appropriate. 1087 GVALinkage Linkage = GetLinkageForVariable(getContext(), D); 1088 if (Linkage == GVA_Internal) 1089 GV->setLinkage(llvm::Function::InternalLinkage); 1090 else if (D->hasAttr<DLLImportAttr>()) 1091 GV->setLinkage(llvm::Function::DLLImportLinkage); 1092 else if (D->hasAttr<DLLExportAttr>()) 1093 GV->setLinkage(llvm::Function::DLLExportLinkage); 1094 else if (D->hasAttr<WeakAttr>()) { 1095 if (GV->isConstant()) 1096 GV->setLinkage(llvm::GlobalVariable::WeakODRLinkage); 1097 else 1098 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1099 } else if (Linkage == GVA_TemplateInstantiation) 1100 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1101 else if (!getLangOptions().CPlusPlus && !CodeGenOpts.NoCommon && 1102 !D->hasExternalStorage() && !D->getInit() && 1103 !D->getAttr<SectionAttr>()) { 1104 GV->setLinkage(llvm::GlobalVariable::CommonLinkage); 1105 // common vars aren't constant even if declared const. 1106 GV->setConstant(false); 1107 } else 1108 GV->setLinkage(llvm::GlobalVariable::ExternalLinkage); 1109 1110 SetCommonAttributes(D, GV); 1111 1112 // Emit global variable debug information. 1113 if (CGDebugInfo *DI = getDebugInfo()) { 1114 DI->setLocation(D->getLocation()); 1115 DI->EmitGlobalVariable(GV, D); 1116 } 1117 } 1118 1119 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 1120 /// implement a function with no prototype, e.g. "int foo() {}". If there are 1121 /// existing call uses of the old function in the module, this adjusts them to 1122 /// call the new function directly. 1123 /// 1124 /// This is not just a cleanup: the always_inline pass requires direct calls to 1125 /// functions to be able to inline them. If there is a bitcast in the way, it 1126 /// won't inline them. Instcombine normally deletes these calls, but it isn't 1127 /// run at -O0. 1128 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 1129 llvm::Function *NewFn) { 1130 // If we're redefining a global as a function, don't transform it. 1131 llvm::Function *OldFn = dyn_cast<llvm::Function>(Old); 1132 if (OldFn == 0) return; 1133 1134 const llvm::Type *NewRetTy = NewFn->getReturnType(); 1135 llvm::SmallVector<llvm::Value*, 4> ArgList; 1136 1137 for (llvm::Value::use_iterator UI = OldFn->use_begin(), E = OldFn->use_end(); 1138 UI != E; ) { 1139 // TODO: Do invokes ever occur in C code? If so, we should handle them too. 1140 unsigned OpNo = UI.getOperandNo(); 1141 llvm::CallInst *CI = dyn_cast<llvm::CallInst>(*UI++); 1142 if (!CI || OpNo != 0) continue; 1143 1144 // If the return types don't match exactly, and if the call isn't dead, then 1145 // we can't transform this call. 1146 if (CI->getType() != NewRetTy && !CI->use_empty()) 1147 continue; 1148 1149 // If the function was passed too few arguments, don't transform. If extra 1150 // arguments were passed, we silently drop them. If any of the types 1151 // mismatch, we don't transform. 1152 unsigned ArgNo = 0; 1153 bool DontTransform = false; 1154 for (llvm::Function::arg_iterator AI = NewFn->arg_begin(), 1155 E = NewFn->arg_end(); AI != E; ++AI, ++ArgNo) { 1156 if (CI->getNumOperands()-1 == ArgNo || 1157 CI->getOperand(ArgNo+1)->getType() != AI->getType()) { 1158 DontTransform = true; 1159 break; 1160 } 1161 } 1162 if (DontTransform) 1163 continue; 1164 1165 // Okay, we can transform this. Create the new call instruction and copy 1166 // over the required information. 1167 ArgList.append(CI->op_begin()+1, CI->op_begin()+1+ArgNo); 1168 llvm::CallInst *NewCall = llvm::CallInst::Create(NewFn, ArgList.begin(), 1169 ArgList.end(), "", CI); 1170 ArgList.clear(); 1171 if (!NewCall->getType()->isVoidTy()) 1172 NewCall->takeName(CI); 1173 NewCall->setAttributes(CI->getAttributes()); 1174 NewCall->setCallingConv(CI->getCallingConv()); 1175 1176 // Finally, remove the old call, replacing any uses with the new one. 1177 if (!CI->use_empty()) 1178 CI->replaceAllUsesWith(NewCall); 1179 1180 // Copy any custom metadata attached with CI. 1181 if (llvm::MDNode *DbgNode = CI->getMetadata("dbg")) 1182 NewCall->setMetadata("dbg", DbgNode); 1183 CI->eraseFromParent(); 1184 } 1185 } 1186 1187 1188 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) { 1189 const llvm::FunctionType *Ty; 1190 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl()); 1191 1192 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 1193 bool isVariadic = D->getType()->getAs<FunctionProtoType>()->isVariadic(); 1194 1195 Ty = getTypes().GetFunctionType(getTypes().getFunctionInfo(MD), isVariadic); 1196 } else { 1197 Ty = cast<llvm::FunctionType>(getTypes().ConvertType(D->getType())); 1198 1199 // As a special case, make sure that definitions of K&R function 1200 // "type foo()" aren't declared as varargs (which forces the backend 1201 // to do unnecessary work). 1202 if (D->getType()->isFunctionNoProtoType()) { 1203 assert(Ty->isVarArg() && "Didn't lower type as expected"); 1204 // Due to stret, the lowered function could have arguments. 1205 // Just create the same type as was lowered by ConvertType 1206 // but strip off the varargs bit. 1207 std::vector<const llvm::Type*> Args(Ty->param_begin(), Ty->param_end()); 1208 Ty = llvm::FunctionType::get(Ty->getReturnType(), Args, false); 1209 } 1210 } 1211 1212 // Get or create the prototype for the function. 1213 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty); 1214 1215 // Strip off a bitcast if we got one back. 1216 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1217 assert(CE->getOpcode() == llvm::Instruction::BitCast); 1218 Entry = CE->getOperand(0); 1219 } 1220 1221 1222 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) { 1223 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry); 1224 1225 // If the types mismatch then we have to rewrite the definition. 1226 assert(OldFn->isDeclaration() && 1227 "Shouldn't replace non-declaration"); 1228 1229 // F is the Function* for the one with the wrong type, we must make a new 1230 // Function* and update everything that used F (a declaration) with the new 1231 // Function* (which will be a definition). 1232 // 1233 // This happens if there is a prototype for a function 1234 // (e.g. "int f()") and then a definition of a different type 1235 // (e.g. "int f(int x)"). Start by making a new function of the 1236 // correct type, RAUW, then steal the name. 1237 GlobalDeclMap.erase(getMangledName(D)); 1238 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty)); 1239 NewFn->takeName(OldFn); 1240 1241 // If this is an implementation of a function without a prototype, try to 1242 // replace any existing uses of the function (which may be calls) with uses 1243 // of the new function 1244 if (D->getType()->isFunctionNoProtoType()) { 1245 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn); 1246 OldFn->removeDeadConstantUsers(); 1247 } 1248 1249 // Replace uses of F with the Function we will endow with a body. 1250 if (!Entry->use_empty()) { 1251 llvm::Constant *NewPtrForOldDecl = 1252 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType()); 1253 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1254 } 1255 1256 // Ok, delete the old function now, which is dead. 1257 OldFn->eraseFromParent(); 1258 1259 Entry = NewFn; 1260 } 1261 1262 llvm::Function *Fn = cast<llvm::Function>(Entry); 1263 1264 CodeGenFunction(*this).GenerateCode(D, Fn); 1265 1266 SetFunctionDefinitionAttributes(D, Fn); 1267 SetLLVMFunctionAttributesForDefinition(D, Fn); 1268 1269 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 1270 AddGlobalCtor(Fn, CA->getPriority()); 1271 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 1272 AddGlobalDtor(Fn, DA->getPriority()); 1273 } 1274 1275 void CodeGenModule::EmitAliasDefinition(const ValueDecl *D) { 1276 const AliasAttr *AA = D->getAttr<AliasAttr>(); 1277 assert(AA && "Not an alias?"); 1278 1279 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 1280 1281 // Unique the name through the identifier table. 1282 const char *AliaseeName = AA->getAliasee().c_str(); 1283 AliaseeName = getContext().Idents.get(AliaseeName).getNameStart(); 1284 1285 // Create a reference to the named value. This ensures that it is emitted 1286 // if a deferred decl. 1287 llvm::Constant *Aliasee; 1288 if (isa<llvm::FunctionType>(DeclTy)) 1289 Aliasee = GetOrCreateLLVMFunction(AliaseeName, DeclTy, GlobalDecl()); 1290 else 1291 Aliasee = GetOrCreateLLVMGlobal(AliaseeName, 1292 llvm::PointerType::getUnqual(DeclTy), 0); 1293 1294 // Create the new alias itself, but don't set a name yet. 1295 llvm::GlobalValue *GA = 1296 new llvm::GlobalAlias(Aliasee->getType(), 1297 llvm::Function::ExternalLinkage, 1298 "", Aliasee, &getModule()); 1299 1300 // See if there is already something with the alias' name in the module. 1301 const char *MangledName = getMangledName(D); 1302 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 1303 1304 if (Entry && !Entry->isDeclaration()) { 1305 // If there is a definition in the module, then it wins over the alias. 1306 // This is dubious, but allow it to be safe. Just ignore the alias. 1307 GA->eraseFromParent(); 1308 return; 1309 } 1310 1311 if (Entry) { 1312 // If there is a declaration in the module, then we had an extern followed 1313 // by the alias, as in: 1314 // extern int test6(); 1315 // ... 1316 // int test6() __attribute__((alias("test7"))); 1317 // 1318 // Remove it and replace uses of it with the alias. 1319 1320 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA, 1321 Entry->getType())); 1322 Entry->eraseFromParent(); 1323 } 1324 1325 // Now we know that there is no conflict, set the name. 1326 Entry = GA; 1327 GA->setName(MangledName); 1328 1329 // Set attributes which are particular to an alias; this is a 1330 // specialization of the attributes which may be set on a global 1331 // variable/function. 1332 if (D->hasAttr<DLLExportAttr>()) { 1333 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1334 // The dllexport attribute is ignored for undefined symbols. 1335 if (FD->getBody()) 1336 GA->setLinkage(llvm::Function::DLLExportLinkage); 1337 } else { 1338 GA->setLinkage(llvm::Function::DLLExportLinkage); 1339 } 1340 } else if (D->hasAttr<WeakAttr>() || 1341 D->hasAttr<WeakImportAttr>()) { 1342 GA->setLinkage(llvm::Function::WeakAnyLinkage); 1343 } 1344 1345 SetCommonAttributes(D, GA); 1346 } 1347 1348 /// getBuiltinLibFunction - Given a builtin id for a function like 1349 /// "__builtin_fabsf", return a Function* for "fabsf". 1350 llvm::Value *CodeGenModule::getBuiltinLibFunction(const FunctionDecl *FD, 1351 unsigned BuiltinID) { 1352 assert((Context.BuiltinInfo.isLibFunction(BuiltinID) || 1353 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) && 1354 "isn't a lib fn"); 1355 1356 // Get the name, skip over the __builtin_ prefix (if necessary). 1357 const char *Name = Context.BuiltinInfo.GetName(BuiltinID); 1358 if (Context.BuiltinInfo.isLibFunction(BuiltinID)) 1359 Name += 10; 1360 1361 const llvm::FunctionType *Ty = 1362 cast<llvm::FunctionType>(getTypes().ConvertType(FD->getType())); 1363 1364 // Unique the name through the identifier table. 1365 Name = getContext().Idents.get(Name).getNameStart(); 1366 return GetOrCreateLLVMFunction(Name, Ty, GlobalDecl(FD)); 1367 } 1368 1369 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,const llvm::Type **Tys, 1370 unsigned NumTys) { 1371 return llvm::Intrinsic::getDeclaration(&getModule(), 1372 (llvm::Intrinsic::ID)IID, Tys, NumTys); 1373 } 1374 1375 llvm::Function *CodeGenModule::getMemCpyFn() { 1376 if (MemCpyFn) return MemCpyFn; 1377 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1378 return MemCpyFn = getIntrinsic(llvm::Intrinsic::memcpy, &IntPtr, 1); 1379 } 1380 1381 llvm::Function *CodeGenModule::getMemMoveFn() { 1382 if (MemMoveFn) return MemMoveFn; 1383 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1384 return MemMoveFn = getIntrinsic(llvm::Intrinsic::memmove, &IntPtr, 1); 1385 } 1386 1387 llvm::Function *CodeGenModule::getMemSetFn() { 1388 if (MemSetFn) return MemSetFn; 1389 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1390 return MemSetFn = getIntrinsic(llvm::Intrinsic::memset, &IntPtr, 1); 1391 } 1392 1393 static llvm::StringMapEntry<llvm::Constant*> & 1394 GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map, 1395 const StringLiteral *Literal, 1396 bool TargetIsLSB, 1397 bool &IsUTF16, 1398 unsigned &StringLength) { 1399 unsigned NumBytes = Literal->getByteLength(); 1400 1401 // Check for simple case. 1402 if (!Literal->containsNonAsciiOrNull()) { 1403 StringLength = NumBytes; 1404 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1405 StringLength)); 1406 } 1407 1408 // Otherwise, convert the UTF8 literals into a byte string. 1409 llvm::SmallVector<UTF16, 128> ToBuf(NumBytes); 1410 const UTF8 *FromPtr = (UTF8 *)Literal->getStrData(); 1411 UTF16 *ToPtr = &ToBuf[0]; 1412 1413 ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, 1414 &ToPtr, ToPtr + NumBytes, 1415 strictConversion); 1416 1417 // Check for conversion failure. 1418 if (Result != conversionOK) { 1419 // FIXME: Have Sema::CheckObjCString() validate the UTF-8 string and remove 1420 // this duplicate code. 1421 assert(Result == sourceIllegal && "UTF-8 to UTF-16 conversion failed"); 1422 StringLength = NumBytes; 1423 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1424 StringLength)); 1425 } 1426 1427 // ConvertUTF8toUTF16 returns the length in ToPtr. 1428 StringLength = ToPtr - &ToBuf[0]; 1429 1430 // Render the UTF-16 string into a byte array and convert to the target byte 1431 // order. 1432 // 1433 // FIXME: This isn't something we should need to do here. 1434 llvm::SmallString<128> AsBytes; 1435 AsBytes.reserve(StringLength * 2); 1436 for (unsigned i = 0; i != StringLength; ++i) { 1437 unsigned short Val = ToBuf[i]; 1438 if (TargetIsLSB) { 1439 AsBytes.push_back(Val & 0xFF); 1440 AsBytes.push_back(Val >> 8); 1441 } else { 1442 AsBytes.push_back(Val >> 8); 1443 AsBytes.push_back(Val & 0xFF); 1444 } 1445 } 1446 // Append one extra null character, the second is automatically added by our 1447 // caller. 1448 AsBytes.push_back(0); 1449 1450 IsUTF16 = true; 1451 return Map.GetOrCreateValue(llvm::StringRef(AsBytes.data(), AsBytes.size())); 1452 } 1453 1454 llvm::Constant * 1455 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 1456 unsigned StringLength = 0; 1457 bool isUTF16 = false; 1458 llvm::StringMapEntry<llvm::Constant*> &Entry = 1459 GetConstantCFStringEntry(CFConstantStringMap, Literal, 1460 getTargetData().isLittleEndian(), 1461 isUTF16, StringLength); 1462 1463 if (llvm::Constant *C = Entry.getValue()) 1464 return C; 1465 1466 llvm::Constant *Zero = 1467 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)); 1468 llvm::Constant *Zeros[] = { Zero, Zero }; 1469 1470 // If we don't already have it, get __CFConstantStringClassReference. 1471 if (!CFConstantStringClassRef) { 1472 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 1473 Ty = llvm::ArrayType::get(Ty, 0); 1474 llvm::Constant *GV = CreateRuntimeVariable(Ty, 1475 "__CFConstantStringClassReference"); 1476 // Decay array -> ptr 1477 CFConstantStringClassRef = 1478 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1479 } 1480 1481 QualType CFTy = getContext().getCFConstantStringType(); 1482 1483 const llvm::StructType *STy = 1484 cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 1485 1486 std::vector<llvm::Constant*> Fields(4); 1487 1488 // Class pointer. 1489 Fields[0] = CFConstantStringClassRef; 1490 1491 // Flags. 1492 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); 1493 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) : 1494 llvm::ConstantInt::get(Ty, 0x07C8); 1495 1496 // String pointer. 1497 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str()); 1498 1499 llvm::GlobalValue::LinkageTypes Linkage; 1500 bool isConstant; 1501 if (isUTF16) { 1502 // FIXME: why do utf strings get "_" labels instead of "L" labels? 1503 Linkage = llvm::GlobalValue::InternalLinkage; 1504 // Note: -fwritable-strings doesn't make unicode CFStrings writable, but 1505 // does make plain ascii ones writable. 1506 isConstant = true; 1507 } else { 1508 Linkage = llvm::GlobalValue::PrivateLinkage; 1509 isConstant = !Features.WritableStrings; 1510 } 1511 1512 llvm::GlobalVariable *GV = 1513 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C, 1514 ".str"); 1515 if (isUTF16) { 1516 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy); 1517 GV->setAlignment(Align.getQuantity()); 1518 } 1519 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1520 1521 // String length. 1522 Ty = getTypes().ConvertType(getContext().LongTy); 1523 Fields[3] = llvm::ConstantInt::get(Ty, StringLength); 1524 1525 // The struct. 1526 C = llvm::ConstantStruct::get(STy, Fields); 1527 GV = new llvm::GlobalVariable(getModule(), C->getType(), true, 1528 llvm::GlobalVariable::PrivateLinkage, C, 1529 "_unnamed_cfstring_"); 1530 if (const char *Sect = getContext().Target.getCFStringSection()) 1531 GV->setSection(Sect); 1532 Entry.setValue(GV); 1533 1534 return GV; 1535 } 1536 1537 /// GetStringForStringLiteral - Return the appropriate bytes for a 1538 /// string literal, properly padded to match the literal type. 1539 std::string CodeGenModule::GetStringForStringLiteral(const StringLiteral *E) { 1540 const char *StrData = E->getStrData(); 1541 unsigned Len = E->getByteLength(); 1542 1543 const ConstantArrayType *CAT = 1544 getContext().getAsConstantArrayType(E->getType()); 1545 assert(CAT && "String isn't pointer or array!"); 1546 1547 // Resize the string to the right size. 1548 std::string Str(StrData, StrData+Len); 1549 uint64_t RealLen = CAT->getSize().getZExtValue(); 1550 1551 if (E->isWide()) 1552 RealLen *= getContext().Target.getWCharWidth()/8; 1553 1554 Str.resize(RealLen, '\0'); 1555 1556 return Str; 1557 } 1558 1559 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a 1560 /// constant array for the given string literal. 1561 llvm::Constant * 1562 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) { 1563 // FIXME: This can be more efficient. 1564 // FIXME: We shouldn't need to bitcast the constant in the wide string case. 1565 llvm::Constant *C = GetAddrOfConstantString(GetStringForStringLiteral(S)); 1566 if (S->isWide()) { 1567 llvm::Type *DestTy = 1568 llvm::PointerType::getUnqual(getTypes().ConvertType(S->getType())); 1569 C = llvm::ConstantExpr::getBitCast(C, DestTy); 1570 } 1571 return C; 1572 } 1573 1574 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 1575 /// array for the given ObjCEncodeExpr node. 1576 llvm::Constant * 1577 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 1578 std::string Str; 1579 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 1580 1581 return GetAddrOfConstantCString(Str); 1582 } 1583 1584 1585 /// GenerateWritableString -- Creates storage for a string literal. 1586 static llvm::Constant *GenerateStringLiteral(const std::string &str, 1587 bool constant, 1588 CodeGenModule &CGM, 1589 const char *GlobalName) { 1590 // Create Constant for this string literal. Don't add a '\0'. 1591 llvm::Constant *C = 1592 llvm::ConstantArray::get(CGM.getLLVMContext(), str, false); 1593 1594 // Create a global variable for this string 1595 return new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant, 1596 llvm::GlobalValue::PrivateLinkage, 1597 C, GlobalName); 1598 } 1599 1600 /// GetAddrOfConstantString - Returns a pointer to a character array 1601 /// containing the literal. This contents are exactly that of the 1602 /// given string, i.e. it will not be null terminated automatically; 1603 /// see GetAddrOfConstantCString. Note that whether the result is 1604 /// actually a pointer to an LLVM constant depends on 1605 /// Feature.WriteableStrings. 1606 /// 1607 /// The result has pointer to array type. 1608 llvm::Constant *CodeGenModule::GetAddrOfConstantString(const std::string &str, 1609 const char *GlobalName) { 1610 bool IsConstant = !Features.WritableStrings; 1611 1612 // Get the default prefix if a name wasn't specified. 1613 if (!GlobalName) 1614 GlobalName = ".str"; 1615 1616 // Don't share any string literals if strings aren't constant. 1617 if (!IsConstant) 1618 return GenerateStringLiteral(str, false, *this, GlobalName); 1619 1620 llvm::StringMapEntry<llvm::Constant *> &Entry = 1621 ConstantStringMap.GetOrCreateValue(&str[0], &str[str.length()]); 1622 1623 if (Entry.getValue()) 1624 return Entry.getValue(); 1625 1626 // Create a global variable for this. 1627 llvm::Constant *C = GenerateStringLiteral(str, true, *this, GlobalName); 1628 Entry.setValue(C); 1629 return C; 1630 } 1631 1632 /// GetAddrOfConstantCString - Returns a pointer to a character 1633 /// array containing the literal and a terminating '\-' 1634 /// character. The result has pointer to array type. 1635 llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &str, 1636 const char *GlobalName){ 1637 return GetAddrOfConstantString(str + '\0', GlobalName); 1638 } 1639 1640 /// EmitObjCPropertyImplementations - Emit information for synthesized 1641 /// properties for an implementation. 1642 void CodeGenModule::EmitObjCPropertyImplementations(const 1643 ObjCImplementationDecl *D) { 1644 for (ObjCImplementationDecl::propimpl_iterator 1645 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) { 1646 ObjCPropertyImplDecl *PID = *i; 1647 1648 // Dynamic is just for type-checking. 1649 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 1650 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 1651 1652 // Determine which methods need to be implemented, some may have 1653 // been overridden. Note that ::isSynthesized is not the method 1654 // we want, that just indicates if the decl came from a 1655 // property. What we want to know is if the method is defined in 1656 // this implementation. 1657 if (!D->getInstanceMethod(PD->getGetterName())) 1658 CodeGenFunction(*this).GenerateObjCGetter( 1659 const_cast<ObjCImplementationDecl *>(D), PID); 1660 if (!PD->isReadOnly() && 1661 !D->getInstanceMethod(PD->getSetterName())) 1662 CodeGenFunction(*this).GenerateObjCSetter( 1663 const_cast<ObjCImplementationDecl *>(D), PID); 1664 } 1665 } 1666 } 1667 1668 /// EmitNamespace - Emit all declarations in a namespace. 1669 void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) { 1670 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end(); 1671 I != E; ++I) 1672 EmitTopLevelDecl(*I); 1673 } 1674 1675 // EmitLinkageSpec - Emit all declarations in a linkage spec. 1676 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 1677 if (LSD->getLanguage() != LinkageSpecDecl::lang_c && 1678 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) { 1679 ErrorUnsupported(LSD, "linkage spec"); 1680 return; 1681 } 1682 1683 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end(); 1684 I != E; ++I) 1685 EmitTopLevelDecl(*I); 1686 } 1687 1688 /// EmitTopLevelDecl - Emit code for a single top level declaration. 1689 void CodeGenModule::EmitTopLevelDecl(Decl *D) { 1690 // If an error has occurred, stop code generation, but continue 1691 // parsing and semantic analysis (to ensure all warnings and errors 1692 // are emitted). 1693 if (Diags.hasErrorOccurred()) 1694 return; 1695 1696 // Ignore dependent declarations. 1697 if (D->getDeclContext() && D->getDeclContext()->isDependentContext()) 1698 return; 1699 1700 switch (D->getKind()) { 1701 case Decl::CXXConversion: 1702 case Decl::CXXMethod: 1703 case Decl::Function: 1704 // Skip function templates 1705 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1706 return; 1707 1708 EmitGlobal(cast<FunctionDecl>(D)); 1709 break; 1710 1711 case Decl::Var: 1712 EmitGlobal(cast<VarDecl>(D)); 1713 break; 1714 1715 // C++ Decls 1716 case Decl::Namespace: 1717 EmitNamespace(cast<NamespaceDecl>(D)); 1718 break; 1719 // No code generation needed. 1720 case Decl::UsingShadow: 1721 case Decl::Using: 1722 case Decl::UsingDirective: 1723 case Decl::ClassTemplate: 1724 case Decl::FunctionTemplate: 1725 case Decl::NamespaceAlias: 1726 break; 1727 case Decl::CXXConstructor: 1728 // Skip function templates 1729 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1730 return; 1731 1732 EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 1733 break; 1734 case Decl::CXXDestructor: 1735 EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 1736 break; 1737 1738 case Decl::StaticAssert: 1739 // Nothing to do. 1740 break; 1741 1742 // Objective-C Decls 1743 1744 // Forward declarations, no (immediate) code generation. 1745 case Decl::ObjCClass: 1746 case Decl::ObjCForwardProtocol: 1747 case Decl::ObjCCategory: 1748 case Decl::ObjCInterface: 1749 break; 1750 1751 case Decl::ObjCProtocol: 1752 Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D)); 1753 break; 1754 1755 case Decl::ObjCCategoryImpl: 1756 // Categories have properties but don't support synthesize so we 1757 // can ignore them here. 1758 Runtime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 1759 break; 1760 1761 case Decl::ObjCImplementation: { 1762 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D); 1763 EmitObjCPropertyImplementations(OMD); 1764 Runtime->GenerateClass(OMD); 1765 break; 1766 } 1767 case Decl::ObjCMethod: { 1768 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D); 1769 // If this is not a prototype, emit the body. 1770 if (OMD->getBody()) 1771 CodeGenFunction(*this).GenerateObjCMethod(OMD); 1772 break; 1773 } 1774 case Decl::ObjCCompatibleAlias: 1775 // compatibility-alias is a directive and has no code gen. 1776 break; 1777 1778 case Decl::LinkageSpec: 1779 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 1780 break; 1781 1782 case Decl::FileScopeAsm: { 1783 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D); 1784 llvm::StringRef AsmString = AD->getAsmString()->getString(); 1785 1786 const std::string &S = getModule().getModuleInlineAsm(); 1787 if (S.empty()) 1788 getModule().setModuleInlineAsm(AsmString); 1789 else 1790 getModule().setModuleInlineAsm(S + '\n' + AsmString.str()); 1791 break; 1792 } 1793 1794 default: 1795 // Make sure we handled everything we should, every other kind is a 1796 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 1797 // function. Need to recode Decl::Kind to do that easily. 1798 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 1799 } 1800 } 1801