CodeGenModule.cpp revision b2bcf1c176b200b36f371e189ce22f93c86cdf45
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" 38using namespace clang; 39using namespace CodeGen; 40 41 42CodeGenModule::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 66CodeGenModule::~CodeGenModule() { 67 delete Runtime; 68 delete DebugInfo; 69} 70 71void 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 80void 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. 94void 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. 107void 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 117LangOptions::VisibilityMode 118CodeGenModule::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 138void 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 157const 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/// 174const 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 186const 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. 195void 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. 202void 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 207void 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 239void 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 255static CodeGenModule::GVALinkage 256GetLinkageForFunction(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). 319void 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 350void 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 361void 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 388void 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 401void 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 412void 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 438void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) { 439 assert(!GV->isDeclaration() && 440 "Only globals with definition can force usage."); 441 LLVMUsed.push_back(GV); 442} 443 444void 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 473void 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/// 507llvm::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 543bool 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 613void 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 (getLangOptions().CPlusPlus && !VD->getInit()) { 631 // In C++, if this is marked "extern", defer code generation. 632 if (VD->getStorageClass() == VarDecl::Extern || VD->isExternC()) 633 return; 634 635 // If this is a declaration of an explicit specialization of a static 636 // data member in a class template, don't emit it. 637 if (VD->isStaticDataMember() && 638 VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 639 return; 640 } 641 642 // In C, if this isn't a definition, defer code generation. 643 if (!getLangOptions().CPlusPlus && !VD->getInit()) 644 return; 645 } 646 647 // Defer code generation when possible if this is a static definition, inline 648 // function etc. These we only want to emit if they are used. 649 if (MayDeferGeneration(Global)) { 650 // If the value has already been used, add it directly to the 651 // DeferredDeclsToEmit list. 652 const char *MangledName = getMangledName(GD); 653 if (GlobalDeclMap.count(MangledName)) 654 DeferredDeclsToEmit.push_back(GD); 655 else { 656 // Otherwise, remember that we saw a deferred decl with this name. The 657 // first use of the mangled name will cause it to move into 658 // DeferredDeclsToEmit. 659 DeferredDecls[MangledName] = GD; 660 } 661 return; 662 } 663 664 // Otherwise emit the definition. 665 EmitGlobalDefinition(GD); 666} 667 668void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) { 669 const ValueDecl *D = cast<ValueDecl>(GD.getDecl()); 670 671 PrettyStackTraceDecl CrashInfo((ValueDecl *)D, D->getLocation(), 672 Context.getSourceManager(), 673 "Generating code for declaration"); 674 675 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 676 getVtableInfo().MaybeEmitVtable(GD); 677 if (MD->isVirtual() && MD->isOutOfLine() && 678 (!isa<CXXDestructorDecl>(D) || GD.getDtorType() != Dtor_Base)) { 679 if (isa<CXXDestructorDecl>(D)) { 680 GlobalDecl CanonGD(cast<CXXDestructorDecl>(D->getCanonicalDecl()), 681 GD.getDtorType()); 682 BuildThunksForVirtual(CanonGD); 683 } else { 684 BuildThunksForVirtual(MD->getCanonicalDecl()); 685 } 686 } 687 } 688 689 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 690 EmitCXXConstructor(CD, GD.getCtorType()); 691 else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(D)) 692 EmitCXXDestructor(DD, GD.getDtorType()); 693 else if (isa<FunctionDecl>(D)) 694 EmitGlobalFunctionDefinition(GD); 695 else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 696 EmitGlobalVarDefinition(VD); 697 else { 698 assert(0 && "Invalid argument to EmitGlobalDefinition()"); 699 } 700} 701 702/// GetOrCreateLLVMFunction - If the specified mangled name is not in the 703/// module, create and return an llvm Function with the specified type. If there 704/// is something in the module with the specified name, return it potentially 705/// bitcasted to the right type. 706/// 707/// If D is non-null, it specifies a decl that correspond to this. This is used 708/// to set the attributes on the function when it is first created. 709llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(const char *MangledName, 710 const llvm::Type *Ty, 711 GlobalDecl D) { 712 // Lookup the entry, lazily creating it if necessary. 713 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 714 if (Entry) { 715 if (Entry->getType()->getElementType() == Ty) 716 return Entry; 717 718 // Make sure the result is of the correct type. 719 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 720 return llvm::ConstantExpr::getBitCast(Entry, PTy); 721 } 722 723 // This function doesn't have a complete type (for example, the return 724 // type is an incomplete struct). Use a fake type instead, and make 725 // sure not to try to set attributes. 726 bool IsIncompleteFunction = false; 727 if (!isa<llvm::FunctionType>(Ty)) { 728 Ty = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 729 std::vector<const llvm::Type*>(), false); 730 IsIncompleteFunction = true; 731 } 732 llvm::Function *F = llvm::Function::Create(cast<llvm::FunctionType>(Ty), 733 llvm::Function::ExternalLinkage, 734 "", &getModule()); 735 F->setName(MangledName); 736 if (D.getDecl()) 737 SetFunctionAttributes(D, F, IsIncompleteFunction); 738 Entry = F; 739 740 // This is the first use or definition of a mangled name. If there is a 741 // deferred decl with this name, remember that we need to emit it at the end 742 // of the file. 743 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 744 DeferredDecls.find(MangledName); 745 if (DDI != DeferredDecls.end()) { 746 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 747 // list, and remove it from DeferredDecls (since we don't need it anymore). 748 DeferredDeclsToEmit.push_back(DDI->second); 749 DeferredDecls.erase(DDI); 750 } else if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl())) { 751 // If this the first reference to a C++ inline function in a class, queue up 752 // the deferred function body for emission. These are not seen as 753 // top-level declarations. 754 if (FD->isThisDeclarationADefinition() && MayDeferGeneration(FD)) 755 DeferredDeclsToEmit.push_back(D); 756 // A called constructor which has no definition or declaration need be 757 // synthesized. 758 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) { 759 if (CD->isImplicit()) 760 DeferredDeclsToEmit.push_back(D); 761 } else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD)) { 762 if (DD->isImplicit()) 763 DeferredDeclsToEmit.push_back(D); 764 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 765 if (MD->isCopyAssignment() && MD->isImplicit()) 766 DeferredDeclsToEmit.push_back(D); 767 } 768 } 769 770 return F; 771} 772 773/// GetAddrOfFunction - Return the address of the given function. If Ty is 774/// non-null, then this function will use the specified type if it has to 775/// create it (this occurs when we see a definition of the function). 776llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD, 777 const llvm::Type *Ty) { 778 // If there was no specific requested type, just convert it now. 779 if (!Ty) 780 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType()); 781 return GetOrCreateLLVMFunction(getMangledName(GD), Ty, GD); 782} 783 784/// CreateRuntimeFunction - Create a new runtime function with the specified 785/// type and name. 786llvm::Constant * 787CodeGenModule::CreateRuntimeFunction(const llvm::FunctionType *FTy, 788 const char *Name) { 789 // Convert Name to be a uniqued string from the IdentifierInfo table. 790 Name = getContext().Idents.get(Name).getNameStart(); 791 return GetOrCreateLLVMFunction(Name, FTy, GlobalDecl()); 792} 793 794static bool DeclIsConstantGlobal(ASTContext &Context, const VarDecl *D) { 795 if (!D->getType().isConstant(Context)) 796 return false; 797 if (Context.getLangOptions().CPlusPlus && 798 Context.getBaseElementType(D->getType())->getAs<RecordType>()) { 799 // FIXME: We should do something fancier here! 800 return false; 801 } 802 return true; 803} 804 805/// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 806/// create and return an llvm GlobalVariable with the specified type. If there 807/// is something in the module with the specified name, return it potentially 808/// bitcasted to the right type. 809/// 810/// If D is non-null, it specifies a decl that correspond to this. This is used 811/// to set the attributes on the global when it is first created. 812llvm::Constant *CodeGenModule::GetOrCreateLLVMGlobal(const char *MangledName, 813 const llvm::PointerType*Ty, 814 const VarDecl *D) { 815 // Lookup the entry, lazily creating it if necessary. 816 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 817 if (Entry) { 818 if (Entry->getType() == Ty) 819 return Entry; 820 821 // Make sure the result is of the correct type. 822 return llvm::ConstantExpr::getBitCast(Entry, Ty); 823 } 824 825 // This is the first use or definition of a mangled name. If there is a 826 // deferred decl with this name, remember that we need to emit it at the end 827 // of the file. 828 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 829 DeferredDecls.find(MangledName); 830 if (DDI != DeferredDecls.end()) { 831 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 832 // list, and remove it from DeferredDecls (since we don't need it anymore). 833 DeferredDeclsToEmit.push_back(DDI->second); 834 DeferredDecls.erase(DDI); 835 } 836 837 llvm::GlobalVariable *GV = 838 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false, 839 llvm::GlobalValue::ExternalLinkage, 840 0, "", 0, 841 false, Ty->getAddressSpace()); 842 GV->setName(MangledName); 843 844 // Handle things which are present even on external declarations. 845 if (D) { 846 // FIXME: This code is overly simple and should be merged with other global 847 // handling. 848 GV->setConstant(DeclIsConstantGlobal(Context, D)); 849 850 // FIXME: Merge with other attribute handling code. 851 if (D->getStorageClass() == VarDecl::PrivateExtern) 852 GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 853 854 if (D->hasAttr<WeakAttr>() || 855 D->hasAttr<WeakImportAttr>()) 856 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 857 858 GV->setThreadLocal(D->isThreadSpecified()); 859 } 860 861 return Entry = GV; 862} 863 864 865/// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 866/// given global variable. If Ty is non-null and if the global doesn't exist, 867/// then it will be greated with the specified type instead of whatever the 868/// normal requested type would be. 869llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 870 const llvm::Type *Ty) { 871 assert(D->hasGlobalStorage() && "Not a global variable"); 872 QualType ASTTy = D->getType(); 873 if (Ty == 0) 874 Ty = getTypes().ConvertTypeForMem(ASTTy); 875 876 const llvm::PointerType *PTy = 877 llvm::PointerType::get(Ty, ASTTy.getAddressSpace()); 878 return GetOrCreateLLVMGlobal(getMangledName(D), PTy, D); 879} 880 881/// CreateRuntimeVariable - Create a new runtime global variable with the 882/// specified type and name. 883llvm::Constant * 884CodeGenModule::CreateRuntimeVariable(const llvm::Type *Ty, 885 const char *Name) { 886 // Convert Name to be a uniqued string from the IdentifierInfo table. 887 Name = getContext().Idents.get(Name).getNameStart(); 888 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0); 889} 890 891void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 892 assert(!D->getInit() && "Cannot emit definite definitions here!"); 893 894 if (MayDeferGeneration(D)) { 895 // If we have not seen a reference to this variable yet, place it 896 // into the deferred declarations table to be emitted if needed 897 // later. 898 const char *MangledName = getMangledName(D); 899 if (GlobalDeclMap.count(MangledName) == 0) { 900 DeferredDecls[MangledName] = D; 901 return; 902 } 903 } 904 905 // The tentative definition is the only definition. 906 EmitGlobalVarDefinition(D); 907} 908 909llvm::GlobalVariable::LinkageTypes 910CodeGenModule::getVtableLinkage(const CXXRecordDecl *RD) { 911 if (RD->isInAnonymousNamespace() || !RD->hasLinkage()) 912 return llvm::GlobalVariable::InternalLinkage; 913 914 if (const CXXMethodDecl *KeyFunction 915 = RD->getASTContext().getKeyFunction(RD)) { 916 // If this class has a key function, use that to determine the linkage of 917 // the vtable. 918 const FunctionDecl *Def = 0; 919 if (KeyFunction->getBody(Def)) 920 KeyFunction = cast<CXXMethodDecl>(Def); 921 922 switch (KeyFunction->getTemplateSpecializationKind()) { 923 case TSK_Undeclared: 924 case TSK_ExplicitSpecialization: 925 if (KeyFunction->isInlined()) 926 return llvm::GlobalVariable::WeakODRLinkage; 927 928 return llvm::GlobalVariable::ExternalLinkage; 929 930 case TSK_ImplicitInstantiation: 931 case TSK_ExplicitInstantiationDefinition: 932 return llvm::GlobalVariable::WeakODRLinkage; 933 934 case TSK_ExplicitInstantiationDeclaration: 935 // FIXME: Use available_externally linkage. However, this currently 936 // breaks LLVM's build due to undefined symbols. 937 // return llvm::GlobalVariable::AvailableExternallyLinkage; 938 return llvm::GlobalVariable::WeakODRLinkage; 939 } 940 } 941 942 switch (RD->getTemplateSpecializationKind()) { 943 case TSK_Undeclared: 944 case TSK_ExplicitSpecialization: 945 case TSK_ImplicitInstantiation: 946 case TSK_ExplicitInstantiationDefinition: 947 return llvm::GlobalVariable::WeakODRLinkage; 948 949 case TSK_ExplicitInstantiationDeclaration: 950 // FIXME: Use available_externally linkage. However, this currently 951 // breaks LLVM's build due to undefined symbols. 952 // return llvm::GlobalVariable::AvailableExternallyLinkage; 953 return llvm::GlobalVariable::WeakODRLinkage; 954 } 955 956 // Silence GCC warning. 957 return llvm::GlobalVariable::WeakODRLinkage; 958} 959 960static CodeGenModule::GVALinkage 961GetLinkageForVariable(ASTContext &Context, const VarDecl *VD) { 962 // If this is a static data member, compute the kind of template 963 // specialization. Otherwise, this variable is not part of a 964 // template. 965 TemplateSpecializationKind TSK = TSK_Undeclared; 966 if (VD->isStaticDataMember()) 967 TSK = VD->getTemplateSpecializationKind(); 968 969 Linkage L = VD->getLinkage(); 970 if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus && 971 VD->getType()->getLinkage() == UniqueExternalLinkage) 972 L = UniqueExternalLinkage; 973 974 switch (L) { 975 case NoLinkage: 976 case InternalLinkage: 977 case UniqueExternalLinkage: 978 return CodeGenModule::GVA_Internal; 979 980 case ExternalLinkage: 981 switch (TSK) { 982 case TSK_Undeclared: 983 case TSK_ExplicitSpecialization: 984 985 // FIXME: ExplicitInstantiationDefinition should be weak! 986 case TSK_ExplicitInstantiationDefinition: 987 return CodeGenModule::GVA_StrongExternal; 988 989 case TSK_ExplicitInstantiationDeclaration: 990 llvm_unreachable("Variable should not be instantiated"); 991 // Fall through to treat this like any other instantiation. 992 993 case TSK_ImplicitInstantiation: 994 return CodeGenModule::GVA_TemplateInstantiation; 995 } 996 } 997 998 return CodeGenModule::GVA_StrongExternal; 999} 1000 1001CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const { 1002 return CharUnits::fromQuantity( 1003 TheTargetData.getTypeStoreSizeInBits(Ty) / Context.getCharWidth()); 1004} 1005 1006void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { 1007 llvm::Constant *Init = 0; 1008 QualType ASTTy = D->getType(); 1009 bool NonConstInit = false; 1010 1011 const Expr *InitExpr = D->getAnyInitializer(); 1012 1013 if (!InitExpr) { 1014 // This is a tentative definition; tentative definitions are 1015 // implicitly initialized with { 0 }. 1016 // 1017 // Note that tentative definitions are only emitted at the end of 1018 // a translation unit, so they should never have incomplete 1019 // type. In addition, EmitTentativeDefinition makes sure that we 1020 // never attempt to emit a tentative definition if a real one 1021 // exists. A use may still exists, however, so we still may need 1022 // to do a RAUW. 1023 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 1024 Init = EmitNullConstant(D->getType()); 1025 } else { 1026 Init = EmitConstantExpr(InitExpr, D->getType()); 1027 1028 if (!Init) { 1029 QualType T = InitExpr->getType(); 1030 if (getLangOptions().CPlusPlus) { 1031 EmitCXXGlobalVarDeclInitFunc(D); 1032 Init = EmitNullConstant(T); 1033 NonConstInit = true; 1034 } else { 1035 ErrorUnsupported(D, "static initializer"); 1036 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 1037 } 1038 } 1039 } 1040 1041 const llvm::Type* InitType = Init->getType(); 1042 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType); 1043 1044 // Strip off a bitcast if we got one back. 1045 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1046 assert(CE->getOpcode() == llvm::Instruction::BitCast || 1047 // all zero index gep. 1048 CE->getOpcode() == llvm::Instruction::GetElementPtr); 1049 Entry = CE->getOperand(0); 1050 } 1051 1052 // Entry is now either a Function or GlobalVariable. 1053 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry); 1054 1055 // We have a definition after a declaration with the wrong type. 1056 // We must make a new GlobalVariable* and update everything that used OldGV 1057 // (a declaration or tentative definition) with the new GlobalVariable* 1058 // (which will be a definition). 1059 // 1060 // This happens if there is a prototype for a global (e.g. 1061 // "extern int x[];") and then a definition of a different type (e.g. 1062 // "int x[10];"). This also happens when an initializer has a different type 1063 // from the type of the global (this happens with unions). 1064 if (GV == 0 || 1065 GV->getType()->getElementType() != InitType || 1066 GV->getType()->getAddressSpace() != ASTTy.getAddressSpace()) { 1067 1068 // Remove the old entry from GlobalDeclMap so that we'll create a new one. 1069 GlobalDeclMap.erase(getMangledName(D)); 1070 1071 // Make a new global with the correct type, this is now guaranteed to work. 1072 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType)); 1073 GV->takeName(cast<llvm::GlobalValue>(Entry)); 1074 1075 // Replace all uses of the old global with the new global 1076 llvm::Constant *NewPtrForOldDecl = 1077 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 1078 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1079 1080 // Erase the old global, since it is no longer used. 1081 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 1082 } 1083 1084 if (const AnnotateAttr *AA = D->getAttr<AnnotateAttr>()) { 1085 SourceManager &SM = Context.getSourceManager(); 1086 AddAnnotation(EmitAnnotateAttr(GV, AA, 1087 SM.getInstantiationLineNumber(D->getLocation()))); 1088 } 1089 1090 GV->setInitializer(Init); 1091 1092 // If it is safe to mark the global 'constant', do so now. 1093 GV->setConstant(false); 1094 if (!NonConstInit && DeclIsConstantGlobal(Context, D)) 1095 GV->setConstant(true); 1096 1097 GV->setAlignment(getContext().getDeclAlign(D).getQuantity()); 1098 1099 // Set the llvm linkage type as appropriate. 1100 GVALinkage Linkage = GetLinkageForVariable(getContext(), D); 1101 if (Linkage == GVA_Internal) 1102 GV->setLinkage(llvm::Function::InternalLinkage); 1103 else if (D->hasAttr<DLLImportAttr>()) 1104 GV->setLinkage(llvm::Function::DLLImportLinkage); 1105 else if (D->hasAttr<DLLExportAttr>()) 1106 GV->setLinkage(llvm::Function::DLLExportLinkage); 1107 else if (D->hasAttr<WeakAttr>()) { 1108 if (GV->isConstant()) 1109 GV->setLinkage(llvm::GlobalVariable::WeakODRLinkage); 1110 else 1111 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1112 } else if (Linkage == GVA_TemplateInstantiation) 1113 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1114 else if (!getLangOptions().CPlusPlus && !CodeGenOpts.NoCommon && 1115 !D->hasExternalStorage() && !D->getInit() && 1116 !D->getAttr<SectionAttr>()) { 1117 GV->setLinkage(llvm::GlobalVariable::CommonLinkage); 1118 // common vars aren't constant even if declared const. 1119 GV->setConstant(false); 1120 } else 1121 GV->setLinkage(llvm::GlobalVariable::ExternalLinkage); 1122 1123 SetCommonAttributes(D, GV); 1124 1125 // Emit global variable debug information. 1126 if (CGDebugInfo *DI = getDebugInfo()) { 1127 DI->setLocation(D->getLocation()); 1128 DI->EmitGlobalVariable(GV, D); 1129 } 1130} 1131 1132/// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 1133/// implement a function with no prototype, e.g. "int foo() {}". If there are 1134/// existing call uses of the old function in the module, this adjusts them to 1135/// call the new function directly. 1136/// 1137/// This is not just a cleanup: the always_inline pass requires direct calls to 1138/// functions to be able to inline them. If there is a bitcast in the way, it 1139/// won't inline them. Instcombine normally deletes these calls, but it isn't 1140/// run at -O0. 1141static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 1142 llvm::Function *NewFn) { 1143 // If we're redefining a global as a function, don't transform it. 1144 llvm::Function *OldFn = dyn_cast<llvm::Function>(Old); 1145 if (OldFn == 0) return; 1146 1147 const llvm::Type *NewRetTy = NewFn->getReturnType(); 1148 llvm::SmallVector<llvm::Value*, 4> ArgList; 1149 1150 for (llvm::Value::use_iterator UI = OldFn->use_begin(), E = OldFn->use_end(); 1151 UI != E; ) { 1152 // TODO: Do invokes ever occur in C code? If so, we should handle them too. 1153 unsigned OpNo = UI.getOperandNo(); 1154 llvm::CallInst *CI = dyn_cast<llvm::CallInst>(*UI++); 1155 if (!CI || OpNo != 0) continue; 1156 1157 // If the return types don't match exactly, and if the call isn't dead, then 1158 // we can't transform this call. 1159 if (CI->getType() != NewRetTy && !CI->use_empty()) 1160 continue; 1161 1162 // If the function was passed too few arguments, don't transform. If extra 1163 // arguments were passed, we silently drop them. If any of the types 1164 // mismatch, we don't transform. 1165 unsigned ArgNo = 0; 1166 bool DontTransform = false; 1167 for (llvm::Function::arg_iterator AI = NewFn->arg_begin(), 1168 E = NewFn->arg_end(); AI != E; ++AI, ++ArgNo) { 1169 if (CI->getNumOperands()-1 == ArgNo || 1170 CI->getOperand(ArgNo+1)->getType() != AI->getType()) { 1171 DontTransform = true; 1172 break; 1173 } 1174 } 1175 if (DontTransform) 1176 continue; 1177 1178 // Okay, we can transform this. Create the new call instruction and copy 1179 // over the required information. 1180 ArgList.append(CI->op_begin()+1, CI->op_begin()+1+ArgNo); 1181 llvm::CallInst *NewCall = llvm::CallInst::Create(NewFn, ArgList.begin(), 1182 ArgList.end(), "", CI); 1183 ArgList.clear(); 1184 if (!NewCall->getType()->isVoidTy()) 1185 NewCall->takeName(CI); 1186 NewCall->setAttributes(CI->getAttributes()); 1187 NewCall->setCallingConv(CI->getCallingConv()); 1188 1189 // Finally, remove the old call, replacing any uses with the new one. 1190 if (!CI->use_empty()) 1191 CI->replaceAllUsesWith(NewCall); 1192 1193 // Copy any custom metadata attached with CI. 1194 if (llvm::MDNode *DbgNode = CI->getMetadata("dbg")) 1195 NewCall->setMetadata("dbg", DbgNode); 1196 CI->eraseFromParent(); 1197 } 1198} 1199 1200 1201void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) { 1202 const llvm::FunctionType *Ty; 1203 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl()); 1204 1205 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 1206 bool isVariadic = D->getType()->getAs<FunctionProtoType>()->isVariadic(); 1207 1208 Ty = getTypes().GetFunctionType(getTypes().getFunctionInfo(MD), isVariadic); 1209 } else { 1210 Ty = cast<llvm::FunctionType>(getTypes().ConvertType(D->getType())); 1211 1212 // As a special case, make sure that definitions of K&R function 1213 // "type foo()" aren't declared as varargs (which forces the backend 1214 // to do unnecessary work). 1215 if (D->getType()->isFunctionNoProtoType()) { 1216 assert(Ty->isVarArg() && "Didn't lower type as expected"); 1217 // Due to stret, the lowered function could have arguments. 1218 // Just create the same type as was lowered by ConvertType 1219 // but strip off the varargs bit. 1220 std::vector<const llvm::Type*> Args(Ty->param_begin(), Ty->param_end()); 1221 Ty = llvm::FunctionType::get(Ty->getReturnType(), Args, false); 1222 } 1223 } 1224 1225 // Get or create the prototype for the function. 1226 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty); 1227 1228 // Strip off a bitcast if we got one back. 1229 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1230 assert(CE->getOpcode() == llvm::Instruction::BitCast); 1231 Entry = CE->getOperand(0); 1232 } 1233 1234 1235 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) { 1236 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry); 1237 1238 // If the types mismatch then we have to rewrite the definition. 1239 assert(OldFn->isDeclaration() && 1240 "Shouldn't replace non-declaration"); 1241 1242 // F is the Function* for the one with the wrong type, we must make a new 1243 // Function* and update everything that used F (a declaration) with the new 1244 // Function* (which will be a definition). 1245 // 1246 // This happens if there is a prototype for a function 1247 // (e.g. "int f()") and then a definition of a different type 1248 // (e.g. "int f(int x)"). Start by making a new function of the 1249 // correct type, RAUW, then steal the name. 1250 GlobalDeclMap.erase(getMangledName(D)); 1251 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty)); 1252 NewFn->takeName(OldFn); 1253 1254 // If this is an implementation of a function without a prototype, try to 1255 // replace any existing uses of the function (which may be calls) with uses 1256 // of the new function 1257 if (D->getType()->isFunctionNoProtoType()) { 1258 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn); 1259 OldFn->removeDeadConstantUsers(); 1260 } 1261 1262 // Replace uses of F with the Function we will endow with a body. 1263 if (!Entry->use_empty()) { 1264 llvm::Constant *NewPtrForOldDecl = 1265 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType()); 1266 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1267 } 1268 1269 // Ok, delete the old function now, which is dead. 1270 OldFn->eraseFromParent(); 1271 1272 Entry = NewFn; 1273 } 1274 1275 llvm::Function *Fn = cast<llvm::Function>(Entry); 1276 1277 CodeGenFunction(*this).GenerateCode(D, Fn); 1278 1279 SetFunctionDefinitionAttributes(D, Fn); 1280 SetLLVMFunctionAttributesForDefinition(D, Fn); 1281 1282 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 1283 AddGlobalCtor(Fn, CA->getPriority()); 1284 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 1285 AddGlobalDtor(Fn, DA->getPriority()); 1286} 1287 1288void CodeGenModule::EmitAliasDefinition(const ValueDecl *D) { 1289 const AliasAttr *AA = D->getAttr<AliasAttr>(); 1290 assert(AA && "Not an alias?"); 1291 1292 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 1293 1294 // Unique the name through the identifier table. 1295 const char *AliaseeName = AA->getAliasee().c_str(); 1296 AliaseeName = getContext().Idents.get(AliaseeName).getNameStart(); 1297 1298 // Create a reference to the named value. This ensures that it is emitted 1299 // if a deferred decl. 1300 llvm::Constant *Aliasee; 1301 if (isa<llvm::FunctionType>(DeclTy)) 1302 Aliasee = GetOrCreateLLVMFunction(AliaseeName, DeclTy, GlobalDecl()); 1303 else 1304 Aliasee = GetOrCreateLLVMGlobal(AliaseeName, 1305 llvm::PointerType::getUnqual(DeclTy), 0); 1306 1307 // Create the new alias itself, but don't set a name yet. 1308 llvm::GlobalValue *GA = 1309 new llvm::GlobalAlias(Aliasee->getType(), 1310 llvm::Function::ExternalLinkage, 1311 "", Aliasee, &getModule()); 1312 1313 // See if there is already something with the alias' name in the module. 1314 const char *MangledName = getMangledName(D); 1315 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 1316 1317 if (Entry && !Entry->isDeclaration()) { 1318 // If there is a definition in the module, then it wins over the alias. 1319 // This is dubious, but allow it to be safe. Just ignore the alias. 1320 GA->eraseFromParent(); 1321 return; 1322 } 1323 1324 if (Entry) { 1325 // If there is a declaration in the module, then we had an extern followed 1326 // by the alias, as in: 1327 // extern int test6(); 1328 // ... 1329 // int test6() __attribute__((alias("test7"))); 1330 // 1331 // Remove it and replace uses of it with the alias. 1332 1333 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA, 1334 Entry->getType())); 1335 Entry->eraseFromParent(); 1336 } 1337 1338 // Now we know that there is no conflict, set the name. 1339 Entry = GA; 1340 GA->setName(MangledName); 1341 1342 // Set attributes which are particular to an alias; this is a 1343 // specialization of the attributes which may be set on a global 1344 // variable/function. 1345 if (D->hasAttr<DLLExportAttr>()) { 1346 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1347 // The dllexport attribute is ignored for undefined symbols. 1348 if (FD->getBody()) 1349 GA->setLinkage(llvm::Function::DLLExportLinkage); 1350 } else { 1351 GA->setLinkage(llvm::Function::DLLExportLinkage); 1352 } 1353 } else if (D->hasAttr<WeakAttr>() || 1354 D->hasAttr<WeakImportAttr>()) { 1355 GA->setLinkage(llvm::Function::WeakAnyLinkage); 1356 } 1357 1358 SetCommonAttributes(D, GA); 1359} 1360 1361/// getBuiltinLibFunction - Given a builtin id for a function like 1362/// "__builtin_fabsf", return a Function* for "fabsf". 1363llvm::Value *CodeGenModule::getBuiltinLibFunction(const FunctionDecl *FD, 1364 unsigned BuiltinID) { 1365 assert((Context.BuiltinInfo.isLibFunction(BuiltinID) || 1366 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) && 1367 "isn't a lib fn"); 1368 1369 // Get the name, skip over the __builtin_ prefix (if necessary). 1370 const char *Name = Context.BuiltinInfo.GetName(BuiltinID); 1371 if (Context.BuiltinInfo.isLibFunction(BuiltinID)) 1372 Name += 10; 1373 1374 const llvm::FunctionType *Ty = 1375 cast<llvm::FunctionType>(getTypes().ConvertType(FD->getType())); 1376 1377 // Unique the name through the identifier table. 1378 Name = getContext().Idents.get(Name).getNameStart(); 1379 return GetOrCreateLLVMFunction(Name, Ty, GlobalDecl(FD)); 1380} 1381 1382llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,const llvm::Type **Tys, 1383 unsigned NumTys) { 1384 return llvm::Intrinsic::getDeclaration(&getModule(), 1385 (llvm::Intrinsic::ID)IID, Tys, NumTys); 1386} 1387 1388llvm::Function *CodeGenModule::getMemCpyFn() { 1389 if (MemCpyFn) return MemCpyFn; 1390 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1391 return MemCpyFn = getIntrinsic(llvm::Intrinsic::memcpy, &IntPtr, 1); 1392} 1393 1394llvm::Function *CodeGenModule::getMemMoveFn() { 1395 if (MemMoveFn) return MemMoveFn; 1396 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1397 return MemMoveFn = getIntrinsic(llvm::Intrinsic::memmove, &IntPtr, 1); 1398} 1399 1400llvm::Function *CodeGenModule::getMemSetFn() { 1401 if (MemSetFn) return MemSetFn; 1402 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1403 return MemSetFn = getIntrinsic(llvm::Intrinsic::memset, &IntPtr, 1); 1404} 1405 1406static llvm::StringMapEntry<llvm::Constant*> & 1407GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map, 1408 const StringLiteral *Literal, 1409 bool TargetIsLSB, 1410 bool &IsUTF16, 1411 unsigned &StringLength) { 1412 unsigned NumBytes = Literal->getByteLength(); 1413 1414 // Check for simple case. 1415 if (!Literal->containsNonAsciiOrNull()) { 1416 StringLength = NumBytes; 1417 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1418 StringLength)); 1419 } 1420 1421 // Otherwise, convert the UTF8 literals into a byte string. 1422 llvm::SmallVector<UTF16, 128> ToBuf(NumBytes); 1423 const UTF8 *FromPtr = (UTF8 *)Literal->getStrData(); 1424 UTF16 *ToPtr = &ToBuf[0]; 1425 1426 ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, 1427 &ToPtr, ToPtr + NumBytes, 1428 strictConversion); 1429 1430 // Check for conversion failure. 1431 if (Result != conversionOK) { 1432 // FIXME: Have Sema::CheckObjCString() validate the UTF-8 string and remove 1433 // this duplicate code. 1434 assert(Result == sourceIllegal && "UTF-8 to UTF-16 conversion failed"); 1435 StringLength = NumBytes; 1436 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1437 StringLength)); 1438 } 1439 1440 // ConvertUTF8toUTF16 returns the length in ToPtr. 1441 StringLength = ToPtr - &ToBuf[0]; 1442 1443 // Render the UTF-16 string into a byte array and convert to the target byte 1444 // order. 1445 // 1446 // FIXME: This isn't something we should need to do here. 1447 llvm::SmallString<128> AsBytes; 1448 AsBytes.reserve(StringLength * 2); 1449 for (unsigned i = 0; i != StringLength; ++i) { 1450 unsigned short Val = ToBuf[i]; 1451 if (TargetIsLSB) { 1452 AsBytes.push_back(Val & 0xFF); 1453 AsBytes.push_back(Val >> 8); 1454 } else { 1455 AsBytes.push_back(Val >> 8); 1456 AsBytes.push_back(Val & 0xFF); 1457 } 1458 } 1459 // Append one extra null character, the second is automatically added by our 1460 // caller. 1461 AsBytes.push_back(0); 1462 1463 IsUTF16 = true; 1464 return Map.GetOrCreateValue(llvm::StringRef(AsBytes.data(), AsBytes.size())); 1465} 1466 1467llvm::Constant * 1468CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 1469 unsigned StringLength = 0; 1470 bool isUTF16 = false; 1471 llvm::StringMapEntry<llvm::Constant*> &Entry = 1472 GetConstantCFStringEntry(CFConstantStringMap, Literal, 1473 getTargetData().isLittleEndian(), 1474 isUTF16, StringLength); 1475 1476 if (llvm::Constant *C = Entry.getValue()) 1477 return C; 1478 1479 llvm::Constant *Zero = 1480 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)); 1481 llvm::Constant *Zeros[] = { Zero, Zero }; 1482 1483 // If we don't already have it, get __CFConstantStringClassReference. 1484 if (!CFConstantStringClassRef) { 1485 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 1486 Ty = llvm::ArrayType::get(Ty, 0); 1487 llvm::Constant *GV = CreateRuntimeVariable(Ty, 1488 "__CFConstantStringClassReference"); 1489 // Decay array -> ptr 1490 CFConstantStringClassRef = 1491 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1492 } 1493 1494 QualType CFTy = getContext().getCFConstantStringType(); 1495 1496 const llvm::StructType *STy = 1497 cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 1498 1499 std::vector<llvm::Constant*> Fields(4); 1500 1501 // Class pointer. 1502 Fields[0] = CFConstantStringClassRef; 1503 1504 // Flags. 1505 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); 1506 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) : 1507 llvm::ConstantInt::get(Ty, 0x07C8); 1508 1509 // String pointer. 1510 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str()); 1511 1512 llvm::GlobalValue::LinkageTypes Linkage; 1513 bool isConstant; 1514 if (isUTF16) { 1515 // FIXME: why do utf strings get "_" labels instead of "L" labels? 1516 Linkage = llvm::GlobalValue::InternalLinkage; 1517 // Note: -fwritable-strings doesn't make unicode CFStrings writable, but 1518 // does make plain ascii ones writable. 1519 isConstant = true; 1520 } else { 1521 Linkage = llvm::GlobalValue::PrivateLinkage; 1522 isConstant = !Features.WritableStrings; 1523 } 1524 1525 llvm::GlobalVariable *GV = 1526 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C, 1527 ".str"); 1528 if (isUTF16) { 1529 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy); 1530 GV->setAlignment(Align.getQuantity()); 1531 } 1532 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1533 1534 // String length. 1535 Ty = getTypes().ConvertType(getContext().LongTy); 1536 Fields[3] = llvm::ConstantInt::get(Ty, StringLength); 1537 1538 // The struct. 1539 C = llvm::ConstantStruct::get(STy, Fields); 1540 GV = new llvm::GlobalVariable(getModule(), C->getType(), true, 1541 llvm::GlobalVariable::PrivateLinkage, C, 1542 "_unnamed_cfstring_"); 1543 if (const char *Sect = getContext().Target.getCFStringSection()) 1544 GV->setSection(Sect); 1545 Entry.setValue(GV); 1546 1547 return GV; 1548} 1549 1550/// GetStringForStringLiteral - Return the appropriate bytes for a 1551/// string literal, properly padded to match the literal type. 1552std::string CodeGenModule::GetStringForStringLiteral(const StringLiteral *E) { 1553 const char *StrData = E->getStrData(); 1554 unsigned Len = E->getByteLength(); 1555 1556 const ConstantArrayType *CAT = 1557 getContext().getAsConstantArrayType(E->getType()); 1558 assert(CAT && "String isn't pointer or array!"); 1559 1560 // Resize the string to the right size. 1561 std::string Str(StrData, StrData+Len); 1562 uint64_t RealLen = CAT->getSize().getZExtValue(); 1563 1564 if (E->isWide()) 1565 RealLen *= getContext().Target.getWCharWidth()/8; 1566 1567 Str.resize(RealLen, '\0'); 1568 1569 return Str; 1570} 1571 1572/// GetAddrOfConstantStringFromLiteral - Return a pointer to a 1573/// constant array for the given string literal. 1574llvm::Constant * 1575CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) { 1576 // FIXME: This can be more efficient. 1577 // FIXME: We shouldn't need to bitcast the constant in the wide string case. 1578 llvm::Constant *C = GetAddrOfConstantString(GetStringForStringLiteral(S)); 1579 if (S->isWide()) { 1580 llvm::Type *DestTy = 1581 llvm::PointerType::getUnqual(getTypes().ConvertType(S->getType())); 1582 C = llvm::ConstantExpr::getBitCast(C, DestTy); 1583 } 1584 return C; 1585} 1586 1587/// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 1588/// array for the given ObjCEncodeExpr node. 1589llvm::Constant * 1590CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 1591 std::string Str; 1592 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 1593 1594 return GetAddrOfConstantCString(Str); 1595} 1596 1597 1598/// GenerateWritableString -- Creates storage for a string literal. 1599static llvm::Constant *GenerateStringLiteral(const std::string &str, 1600 bool constant, 1601 CodeGenModule &CGM, 1602 const char *GlobalName) { 1603 // Create Constant for this string literal. Don't add a '\0'. 1604 llvm::Constant *C = 1605 llvm::ConstantArray::get(CGM.getLLVMContext(), str, false); 1606 1607 // Create a global variable for this string 1608 return new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant, 1609 llvm::GlobalValue::PrivateLinkage, 1610 C, GlobalName); 1611} 1612 1613/// GetAddrOfConstantString - Returns a pointer to a character array 1614/// containing the literal. This contents are exactly that of the 1615/// given string, i.e. it will not be null terminated automatically; 1616/// see GetAddrOfConstantCString. Note that whether the result is 1617/// actually a pointer to an LLVM constant depends on 1618/// Feature.WriteableStrings. 1619/// 1620/// The result has pointer to array type. 1621llvm::Constant *CodeGenModule::GetAddrOfConstantString(const std::string &str, 1622 const char *GlobalName) { 1623 bool IsConstant = !Features.WritableStrings; 1624 1625 // Get the default prefix if a name wasn't specified. 1626 if (!GlobalName) 1627 GlobalName = ".str"; 1628 1629 // Don't share any string literals if strings aren't constant. 1630 if (!IsConstant) 1631 return GenerateStringLiteral(str, false, *this, GlobalName); 1632 1633 llvm::StringMapEntry<llvm::Constant *> &Entry = 1634 ConstantStringMap.GetOrCreateValue(&str[0], &str[str.length()]); 1635 1636 if (Entry.getValue()) 1637 return Entry.getValue(); 1638 1639 // Create a global variable for this. 1640 llvm::Constant *C = GenerateStringLiteral(str, true, *this, GlobalName); 1641 Entry.setValue(C); 1642 return C; 1643} 1644 1645/// GetAddrOfConstantCString - Returns a pointer to a character 1646/// array containing the literal and a terminating '\-' 1647/// character. The result has pointer to array type. 1648llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &str, 1649 const char *GlobalName){ 1650 return GetAddrOfConstantString(str + '\0', GlobalName); 1651} 1652 1653/// EmitObjCPropertyImplementations - Emit information for synthesized 1654/// properties for an implementation. 1655void CodeGenModule::EmitObjCPropertyImplementations(const 1656 ObjCImplementationDecl *D) { 1657 for (ObjCImplementationDecl::propimpl_iterator 1658 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) { 1659 ObjCPropertyImplDecl *PID = *i; 1660 1661 // Dynamic is just for type-checking. 1662 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 1663 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 1664 1665 // Determine which methods need to be implemented, some may have 1666 // been overridden. Note that ::isSynthesized is not the method 1667 // we want, that just indicates if the decl came from a 1668 // property. What we want to know is if the method is defined in 1669 // this implementation. 1670 if (!D->getInstanceMethod(PD->getGetterName())) 1671 CodeGenFunction(*this).GenerateObjCGetter( 1672 const_cast<ObjCImplementationDecl *>(D), PID); 1673 if (!PD->isReadOnly() && 1674 !D->getInstanceMethod(PD->getSetterName())) 1675 CodeGenFunction(*this).GenerateObjCSetter( 1676 const_cast<ObjCImplementationDecl *>(D), PID); 1677 } 1678 } 1679} 1680 1681/// EmitNamespace - Emit all declarations in a namespace. 1682void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) { 1683 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end(); 1684 I != E; ++I) 1685 EmitTopLevelDecl(*I); 1686} 1687 1688// EmitLinkageSpec - Emit all declarations in a linkage spec. 1689void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 1690 if (LSD->getLanguage() != LinkageSpecDecl::lang_c && 1691 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) { 1692 ErrorUnsupported(LSD, "linkage spec"); 1693 return; 1694 } 1695 1696 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end(); 1697 I != E; ++I) 1698 EmitTopLevelDecl(*I); 1699} 1700 1701/// EmitTopLevelDecl - Emit code for a single top level declaration. 1702void CodeGenModule::EmitTopLevelDecl(Decl *D) { 1703 // If an error has occurred, stop code generation, but continue 1704 // parsing and semantic analysis (to ensure all warnings and errors 1705 // are emitted). 1706 if (Diags.hasErrorOccurred()) 1707 return; 1708 1709 // Ignore dependent declarations. 1710 if (D->getDeclContext() && D->getDeclContext()->isDependentContext()) 1711 return; 1712 1713 switch (D->getKind()) { 1714 case Decl::CXXConversion: 1715 case Decl::CXXMethod: 1716 case Decl::Function: 1717 // Skip function templates 1718 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1719 return; 1720 1721 EmitGlobal(cast<FunctionDecl>(D)); 1722 break; 1723 1724 case Decl::Var: 1725 EmitGlobal(cast<VarDecl>(D)); 1726 break; 1727 1728 // C++ Decls 1729 case Decl::Namespace: 1730 EmitNamespace(cast<NamespaceDecl>(D)); 1731 break; 1732 // No code generation needed. 1733 case Decl::UsingShadow: 1734 case Decl::Using: 1735 case Decl::UsingDirective: 1736 case Decl::ClassTemplate: 1737 case Decl::FunctionTemplate: 1738 case Decl::NamespaceAlias: 1739 break; 1740 case Decl::CXXConstructor: 1741 // Skip function templates 1742 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1743 return; 1744 1745 EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 1746 break; 1747 case Decl::CXXDestructor: 1748 EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 1749 break; 1750 1751 case Decl::StaticAssert: 1752 // Nothing to do. 1753 break; 1754 1755 // Objective-C Decls 1756 1757 // Forward declarations, no (immediate) code generation. 1758 case Decl::ObjCClass: 1759 case Decl::ObjCForwardProtocol: 1760 case Decl::ObjCCategory: 1761 case Decl::ObjCInterface: 1762 break; 1763 1764 case Decl::ObjCProtocol: 1765 Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D)); 1766 break; 1767 1768 case Decl::ObjCCategoryImpl: 1769 // Categories have properties but don't support synthesize so we 1770 // can ignore them here. 1771 Runtime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 1772 break; 1773 1774 case Decl::ObjCImplementation: { 1775 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D); 1776 EmitObjCPropertyImplementations(OMD); 1777 Runtime->GenerateClass(OMD); 1778 break; 1779 } 1780 case Decl::ObjCMethod: { 1781 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D); 1782 // If this is not a prototype, emit the body. 1783 if (OMD->getBody()) 1784 CodeGenFunction(*this).GenerateObjCMethod(OMD); 1785 break; 1786 } 1787 case Decl::ObjCCompatibleAlias: 1788 // compatibility-alias is a directive and has no code gen. 1789 break; 1790 1791 case Decl::LinkageSpec: 1792 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 1793 break; 1794 1795 case Decl::FileScopeAsm: { 1796 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D); 1797 llvm::StringRef AsmString = AD->getAsmString()->getString(); 1798 1799 const std::string &S = getModule().getModuleInlineAsm(); 1800 if (S.empty()) 1801 getModule().setModuleInlineAsm(AsmString); 1802 else 1803 getModule().setModuleInlineAsm(S + '\n' + AsmString.str()); 1804 break; 1805 } 1806 1807 default: 1808 // Make sure we handled everything we should, every other kind is a 1809 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 1810 // function. Need to recode Decl::Kind to do that easily. 1811 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 1812 } 1813} 1814