CodeGenModule.cpp revision 2357aeec0da2740838963880edd97e43f14cb6fd
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 "CodeGenTBAA.h" 18#include "CGCall.h" 19#include "CGCXXABI.h" 20#include "CGObjCRuntime.h" 21#include "TargetInfo.h" 22#include "clang/Frontend/CodeGenOptions.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CharUnits.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/DeclCXX.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/Mangle.h" 29#include "clang/AST/RecordLayout.h" 30#include "clang/Basic/Builtins.h" 31#include "clang/Basic/Diagnostic.h" 32#include "clang/Basic/SourceManager.h" 33#include "clang/Basic/TargetInfo.h" 34#include "clang/Basic/ConvertUTF.h" 35#include "llvm/CallingConv.h" 36#include "llvm/Module.h" 37#include "llvm/Intrinsics.h" 38#include "llvm/LLVMContext.h" 39#include "llvm/ADT/Triple.h" 40#include "llvm/Target/Mangler.h" 41#include "llvm/Target/TargetData.h" 42#include "llvm/Support/CallSite.h" 43#include "llvm/Support/ErrorHandling.h" 44using namespace clang; 45using namespace CodeGen; 46 47static CGCXXABI &createCXXABI(CodeGenModule &CGM) { 48 switch (CGM.getContext().Target.getCXXABI()) { 49 case CXXABI_ARM: return *CreateARMCXXABI(CGM); 50 case CXXABI_Itanium: return *CreateItaniumCXXABI(CGM); 51 case CXXABI_Microsoft: return *CreateMicrosoftCXXABI(CGM); 52 } 53 54 llvm_unreachable("invalid C++ ABI kind"); 55 return *CreateItaniumCXXABI(CGM); 56} 57 58 59CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO, 60 llvm::Module &M, const llvm::TargetData &TD, 61 Diagnostic &diags) 62 : Context(C), Features(C.getLangOptions()), CodeGenOpts(CGO), TheModule(M), 63 TheTargetData(TD), TheTargetCodeGenInfo(0), Diags(diags), 64 ABI(createCXXABI(*this)), 65 Types(C, M, TD, getTargetCodeGenInfo().getABIInfo(), ABI, CGO), 66 TBAA(0), 67 VTables(*this), Runtime(0), DebugInfo(0), ARCData(0), RRData(0), 68 CFConstantStringClassRef(0), ConstantStringClassRef(0), 69 VMContext(M.getContext()), 70 NSConcreteGlobalBlockDecl(0), NSConcreteStackBlockDecl(0), 71 NSConcreteGlobalBlock(0), NSConcreteStackBlock(0), 72 BlockObjectAssignDecl(0), BlockObjectDisposeDecl(0), 73 BlockObjectAssign(0), BlockObjectDispose(0), 74 BlockDescriptorType(0), GenericBlockLiteralType(0) { 75 if (Features.ObjC1) 76 createObjCRuntime(); 77 78 // Enable TBAA unless it's suppressed. 79 if (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0) 80 TBAA = new CodeGenTBAA(Context, VMContext, getLangOptions(), 81 ABI.getMangleContext()); 82 83 // If debug info or coverage generation is enabled, create the CGDebugInfo 84 // object. 85 if (CodeGenOpts.DebugInfo || CodeGenOpts.EmitGcovArcs || 86 CodeGenOpts.EmitGcovNotes) 87 DebugInfo = new CGDebugInfo(*this); 88 89 Block.GlobalUniqueCount = 0; 90 91 if (C.getLangOptions().ObjCAutoRefCount) 92 ARCData = new ARCEntrypoints(); 93 RRData = new RREntrypoints(); 94 95 // Initialize the type cache. 96 llvm::LLVMContext &LLVMContext = M.getContext(); 97 VoidTy = llvm::Type::getVoidTy(LLVMContext); 98 Int8Ty = llvm::Type::getInt8Ty(LLVMContext); 99 Int32Ty = llvm::Type::getInt32Ty(LLVMContext); 100 Int64Ty = llvm::Type::getInt64Ty(LLVMContext); 101 PointerWidthInBits = C.Target.getPointerWidth(0); 102 PointerAlignInBytes = 103 C.toCharUnitsFromBits(C.Target.getPointerAlign(0)).getQuantity(); 104 IntTy = llvm::IntegerType::get(LLVMContext, C.Target.getIntWidth()); 105 IntPtrTy = llvm::IntegerType::get(LLVMContext, PointerWidthInBits); 106 Int8PtrTy = Int8Ty->getPointerTo(0); 107 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0); 108} 109 110CodeGenModule::~CodeGenModule() { 111 delete Runtime; 112 delete &ABI; 113 delete TBAA; 114 delete DebugInfo; 115 delete ARCData; 116 delete RRData; 117} 118 119void CodeGenModule::createObjCRuntime() { 120 if (!Features.NeXTRuntime) 121 Runtime = CreateGNUObjCRuntime(*this); 122 else 123 Runtime = CreateMacObjCRuntime(*this); 124} 125 126void CodeGenModule::Release() { 127 EmitDeferred(); 128 EmitCXXGlobalInitFunc(); 129 EmitCXXGlobalDtorFunc(); 130 if (Runtime) 131 if (llvm::Function *ObjCInitFunction = Runtime->ModuleInitFunction()) 132 AddGlobalCtor(ObjCInitFunction); 133 EmitCtorList(GlobalCtors, "llvm.global_ctors"); 134 EmitCtorList(GlobalDtors, "llvm.global_dtors"); 135 EmitAnnotations(); 136 EmitLLVMUsed(); 137 138 SimplifyPersonality(); 139 140 if (getCodeGenOpts().EmitDeclMetadata) 141 EmitDeclMetadata(); 142 143 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes) 144 EmitCoverageFile(); 145} 146 147void CodeGenModule::UpdateCompletedType(const TagDecl *TD) { 148 // Make sure that this type is translated. 149 Types.UpdateCompletedType(TD); 150 if (DebugInfo) 151 DebugInfo->UpdateCompletedType(TD); 152} 153 154llvm::MDNode *CodeGenModule::getTBAAInfo(QualType QTy) { 155 if (!TBAA) 156 return 0; 157 return TBAA->getTBAAInfo(QTy); 158} 159 160void CodeGenModule::DecorateInstruction(llvm::Instruction *Inst, 161 llvm::MDNode *TBAAInfo) { 162 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, TBAAInfo); 163} 164 165bool CodeGenModule::isTargetDarwin() const { 166 return getContext().Target.getTriple().isOSDarwin(); 167} 168 169void CodeGenModule::Error(SourceLocation loc, llvm::StringRef error) { 170 unsigned diagID = getDiags().getCustomDiagID(Diagnostic::Error, error); 171 getDiags().Report(Context.getFullLoc(loc), diagID); 172} 173 174/// ErrorUnsupported - Print out an error that codegen doesn't support the 175/// specified stmt yet. 176void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type, 177 bool OmitOnError) { 178 if (OmitOnError && getDiags().hasErrorOccurred()) 179 return; 180 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 181 "cannot compile this %0 yet"); 182 std::string Msg = Type; 183 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID) 184 << Msg << S->getSourceRange(); 185} 186 187/// ErrorUnsupported - Print out an error that codegen doesn't support the 188/// specified decl yet. 189void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type, 190 bool OmitOnError) { 191 if (OmitOnError && getDiags().hasErrorOccurred()) 192 return; 193 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 194 "cannot compile this %0 yet"); 195 std::string Msg = Type; 196 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg; 197} 198 199llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) { 200 return llvm::ConstantInt::get(SizeTy, size.getQuantity()); 201} 202 203void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV, 204 const NamedDecl *D) const { 205 // Internal definitions always have default visibility. 206 if (GV->hasLocalLinkage()) { 207 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 208 return; 209 } 210 211 // Set visibility for definitions. 212 NamedDecl::LinkageInfo LV = D->getLinkageAndVisibility(); 213 if (LV.visibilityExplicit() || !GV->hasAvailableExternallyLinkage()) 214 GV->setVisibility(GetLLVMVisibility(LV.visibility())); 215} 216 217/// Set the symbol visibility of type information (vtable and RTTI) 218/// associated with the given type. 219void CodeGenModule::setTypeVisibility(llvm::GlobalValue *GV, 220 const CXXRecordDecl *RD, 221 TypeVisibilityKind TVK) const { 222 setGlobalVisibility(GV, RD); 223 224 if (!CodeGenOpts.HiddenWeakVTables) 225 return; 226 227 // We never want to drop the visibility for RTTI names. 228 if (TVK == TVK_ForRTTIName) 229 return; 230 231 // We want to drop the visibility to hidden for weak type symbols. 232 // This isn't possible if there might be unresolved references 233 // elsewhere that rely on this symbol being visible. 234 235 // This should be kept roughly in sync with setThunkVisibility 236 // in CGVTables.cpp. 237 238 // Preconditions. 239 if (GV->getLinkage() != llvm::GlobalVariable::LinkOnceODRLinkage || 240 GV->getVisibility() != llvm::GlobalVariable::DefaultVisibility) 241 return; 242 243 // Don't override an explicit visibility attribute. 244 if (RD->getExplicitVisibility()) 245 return; 246 247 switch (RD->getTemplateSpecializationKind()) { 248 // We have to disable the optimization if this is an EI definition 249 // because there might be EI declarations in other shared objects. 250 case TSK_ExplicitInstantiationDefinition: 251 case TSK_ExplicitInstantiationDeclaration: 252 return; 253 254 // Every use of a non-template class's type information has to emit it. 255 case TSK_Undeclared: 256 break; 257 258 // In theory, implicit instantiations can ignore the possibility of 259 // an explicit instantiation declaration because there necessarily 260 // must be an EI definition somewhere with default visibility. In 261 // practice, it's possible to have an explicit instantiation for 262 // an arbitrary template class, and linkers aren't necessarily able 263 // to deal with mixed-visibility symbols. 264 case TSK_ExplicitSpecialization: 265 case TSK_ImplicitInstantiation: 266 if (!CodeGenOpts.HiddenWeakTemplateVTables) 267 return; 268 break; 269 } 270 271 // If there's a key function, there may be translation units 272 // that don't have the key function's definition. But ignore 273 // this if we're emitting RTTI under -fno-rtti. 274 if (!(TVK != TVK_ForRTTI) || Features.RTTI) { 275 if (Context.getKeyFunction(RD)) 276 return; 277 } 278 279 // Otherwise, drop the visibility to hidden. 280 GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 281 GV->setUnnamedAddr(true); 282} 283 284llvm::StringRef CodeGenModule::getMangledName(GlobalDecl GD) { 285 const NamedDecl *ND = cast<NamedDecl>(GD.getDecl()); 286 287 llvm::StringRef &Str = MangledDeclNames[GD.getCanonicalDecl()]; 288 if (!Str.empty()) 289 return Str; 290 291 if (!getCXXABI().getMangleContext().shouldMangleDeclName(ND)) { 292 IdentifierInfo *II = ND->getIdentifier(); 293 assert(II && "Attempt to mangle unnamed decl."); 294 295 Str = II->getName(); 296 return Str; 297 } 298 299 llvm::SmallString<256> Buffer; 300 llvm::raw_svector_ostream Out(Buffer); 301 if (const CXXConstructorDecl *D = dyn_cast<CXXConstructorDecl>(ND)) 302 getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out); 303 else if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND)) 304 getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out); 305 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(ND)) 306 getCXXABI().getMangleContext().mangleBlock(BD, Out); 307 else 308 getCXXABI().getMangleContext().mangleName(ND, Out); 309 310 // Allocate space for the mangled name. 311 Out.flush(); 312 size_t Length = Buffer.size(); 313 char *Name = MangledNamesAllocator.Allocate<char>(Length); 314 std::copy(Buffer.begin(), Buffer.end(), Name); 315 316 Str = llvm::StringRef(Name, Length); 317 318 return Str; 319} 320 321void CodeGenModule::getBlockMangledName(GlobalDecl GD, MangleBuffer &Buffer, 322 const BlockDecl *BD) { 323 MangleContext &MangleCtx = getCXXABI().getMangleContext(); 324 const Decl *D = GD.getDecl(); 325 llvm::raw_svector_ostream Out(Buffer.getBuffer()); 326 if (D == 0) 327 MangleCtx.mangleGlobalBlock(BD, Out); 328 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 329 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out); 330 else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(D)) 331 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out); 332 else 333 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out); 334} 335 336llvm::GlobalValue *CodeGenModule::GetGlobalValue(llvm::StringRef Name) { 337 return getModule().getNamedValue(Name); 338} 339 340/// AddGlobalCtor - Add a function to the list that will be called before 341/// main() runs. 342void CodeGenModule::AddGlobalCtor(llvm::Function * Ctor, int Priority) { 343 // FIXME: Type coercion of void()* types. 344 GlobalCtors.push_back(std::make_pair(Ctor, Priority)); 345} 346 347/// AddGlobalDtor - Add a function to the list that will be called 348/// when the module is unloaded. 349void CodeGenModule::AddGlobalDtor(llvm::Function * Dtor, int Priority) { 350 // FIXME: Type coercion of void()* types. 351 GlobalDtors.push_back(std::make_pair(Dtor, Priority)); 352} 353 354void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) { 355 // Ctor function type is void()*. 356 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false); 357 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy); 358 359 // Get the type of a ctor entry, { i32, void ()* }. 360 llvm::StructType *CtorStructTy = 361 llvm::StructType::get(llvm::Type::getInt32Ty(VMContext), 362 llvm::PointerType::getUnqual(CtorFTy), NULL); 363 364 // Construct the constructor and destructor arrays. 365 std::vector<llvm::Constant*> Ctors; 366 for (CtorList::const_iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 367 std::vector<llvm::Constant*> S; 368 S.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 369 I->second, false)); 370 S.push_back(llvm::ConstantExpr::getBitCast(I->first, CtorPFTy)); 371 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S)); 372 } 373 374 if (!Ctors.empty()) { 375 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size()); 376 new llvm::GlobalVariable(TheModule, AT, false, 377 llvm::GlobalValue::AppendingLinkage, 378 llvm::ConstantArray::get(AT, Ctors), 379 GlobalName); 380 } 381} 382 383void CodeGenModule::EmitAnnotations() { 384 if (Annotations.empty()) 385 return; 386 387 // Create a new global variable for the ConstantStruct in the Module. 388 llvm::Constant *Array = 389 llvm::ConstantArray::get(llvm::ArrayType::get(Annotations[0]->getType(), 390 Annotations.size()), 391 Annotations); 392 llvm::GlobalValue *gv = 393 new llvm::GlobalVariable(TheModule, Array->getType(), false, 394 llvm::GlobalValue::AppendingLinkage, Array, 395 "llvm.global.annotations"); 396 gv->setSection("llvm.metadata"); 397} 398 399llvm::GlobalValue::LinkageTypes 400CodeGenModule::getFunctionLinkage(const FunctionDecl *D) { 401 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D); 402 403 if (Linkage == GVA_Internal) 404 return llvm::Function::InternalLinkage; 405 406 if (D->hasAttr<DLLExportAttr>()) 407 return llvm::Function::DLLExportLinkage; 408 409 if (D->hasAttr<WeakAttr>()) 410 return llvm::Function::WeakAnyLinkage; 411 412 // In C99 mode, 'inline' functions are guaranteed to have a strong 413 // definition somewhere else, so we can use available_externally linkage. 414 if (Linkage == GVA_C99Inline) 415 return llvm::Function::AvailableExternallyLinkage; 416 417 // In C++, the compiler has to emit a definition in every translation unit 418 // that references the function. We should use linkonce_odr because 419 // a) if all references in this translation unit are optimized away, we 420 // don't need to codegen it. b) if the function persists, it needs to be 421 // merged with other definitions. c) C++ has the ODR, so we know the 422 // definition is dependable. 423 if (Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation) 424 return !Context.getLangOptions().AppleKext 425 ? llvm::Function::LinkOnceODRLinkage 426 : llvm::Function::InternalLinkage; 427 428 // An explicit instantiation of a template has weak linkage, since 429 // explicit instantiations can occur in multiple translation units 430 // and must all be equivalent. However, we are not allowed to 431 // throw away these explicit instantiations. 432 if (Linkage == GVA_ExplicitTemplateInstantiation) 433 return !Context.getLangOptions().AppleKext 434 ? llvm::Function::WeakODRLinkage 435 : llvm::Function::InternalLinkage; 436 437 // Otherwise, we have strong external linkage. 438 assert(Linkage == GVA_StrongExternal); 439 return llvm::Function::ExternalLinkage; 440} 441 442 443/// SetFunctionDefinitionAttributes - Set attributes for a global. 444/// 445/// FIXME: This is currently only done for aliases and functions, but not for 446/// variables (these details are set in EmitGlobalVarDefinition for variables). 447void CodeGenModule::SetFunctionDefinitionAttributes(const FunctionDecl *D, 448 llvm::GlobalValue *GV) { 449 SetCommonAttributes(D, GV); 450} 451 452void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D, 453 const CGFunctionInfo &Info, 454 llvm::Function *F) { 455 unsigned CallingConv; 456 AttributeListType AttributeList; 457 ConstructAttributeList(Info, D, AttributeList, CallingConv); 458 F->setAttributes(llvm::AttrListPtr::get(AttributeList.begin(), 459 AttributeList.size())); 460 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 461} 462 463void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 464 llvm::Function *F) { 465 if (CodeGenOpts.UnwindTables) 466 F->setHasUWTable(); 467 468 if (!Features.Exceptions && !Features.ObjCNonFragileABI) 469 F->addFnAttr(llvm::Attribute::NoUnwind); 470 471 if (D->hasAttr<AlwaysInlineAttr>()) 472 F->addFnAttr(llvm::Attribute::AlwaysInline); 473 474 if (D->hasAttr<NakedAttr>()) 475 F->addFnAttr(llvm::Attribute::Naked); 476 477 if (D->hasAttr<NoInlineAttr>()) 478 F->addFnAttr(llvm::Attribute::NoInline); 479 480 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D)) 481 F->setUnnamedAddr(true); 482 483 if (Features.getStackProtectorMode() == LangOptions::SSPOn) 484 F->addFnAttr(llvm::Attribute::StackProtect); 485 else if (Features.getStackProtectorMode() == LangOptions::SSPReq) 486 F->addFnAttr(llvm::Attribute::StackProtectReq); 487 488 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth(); 489 if (alignment) 490 F->setAlignment(alignment); 491 492 // C++ ABI requires 2-byte alignment for member functions. 493 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D)) 494 F->setAlignment(2); 495} 496 497void CodeGenModule::SetCommonAttributes(const Decl *D, 498 llvm::GlobalValue *GV) { 499 if (const NamedDecl *ND = dyn_cast<NamedDecl>(D)) 500 setGlobalVisibility(GV, ND); 501 else 502 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 503 504 if (D->hasAttr<UsedAttr>()) 505 AddUsedGlobal(GV); 506 507 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 508 GV->setSection(SA->getName()); 509 510 getTargetCodeGenInfo().SetTargetAttributes(D, GV, *this); 511} 512 513void CodeGenModule::SetInternalFunctionAttributes(const Decl *D, 514 llvm::Function *F, 515 const CGFunctionInfo &FI) { 516 SetLLVMFunctionAttributes(D, FI, F); 517 SetLLVMFunctionAttributesForDefinition(D, F); 518 519 F->setLinkage(llvm::Function::InternalLinkage); 520 521 SetCommonAttributes(D, F); 522} 523 524void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, 525 llvm::Function *F, 526 bool IsIncompleteFunction) { 527 if (unsigned IID = F->getIntrinsicID()) { 528 // If this is an intrinsic function, set the function's attributes 529 // to the intrinsic's attributes. 530 F->setAttributes(llvm::Intrinsic::getAttributes((llvm::Intrinsic::ID)IID)); 531 return; 532 } 533 534 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 535 536 if (!IsIncompleteFunction) 537 SetLLVMFunctionAttributes(FD, getTypes().getFunctionInfo(GD), F); 538 539 // Only a few attributes are set on declarations; these may later be 540 // overridden by a definition. 541 542 if (FD->hasAttr<DLLImportAttr>()) { 543 F->setLinkage(llvm::Function::DLLImportLinkage); 544 } else if (FD->hasAttr<WeakAttr>() || 545 FD->isWeakImported()) { 546 // "extern_weak" is overloaded in LLVM; we probably should have 547 // separate linkage types for this. 548 F->setLinkage(llvm::Function::ExternalWeakLinkage); 549 } else { 550 F->setLinkage(llvm::Function::ExternalLinkage); 551 552 NamedDecl::LinkageInfo LV = FD->getLinkageAndVisibility(); 553 if (LV.linkage() == ExternalLinkage && LV.visibilityExplicit()) { 554 F->setVisibility(GetLLVMVisibility(LV.visibility())); 555 } 556 } 557 558 if (const SectionAttr *SA = FD->getAttr<SectionAttr>()) 559 F->setSection(SA->getName()); 560} 561 562void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) { 563 assert(!GV->isDeclaration() && 564 "Only globals with definition can force usage."); 565 LLVMUsed.push_back(GV); 566} 567 568void CodeGenModule::EmitLLVMUsed() { 569 // Don't create llvm.used if there is no need. 570 if (LLVMUsed.empty()) 571 return; 572 573 const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext); 574 575 // Convert LLVMUsed to what ConstantArray needs. 576 std::vector<llvm::Constant*> UsedArray; 577 UsedArray.resize(LLVMUsed.size()); 578 for (unsigned i = 0, e = LLVMUsed.size(); i != e; ++i) { 579 UsedArray[i] = 580 llvm::ConstantExpr::getBitCast(cast<llvm::Constant>(&*LLVMUsed[i]), 581 i8PTy); 582 } 583 584 if (UsedArray.empty()) 585 return; 586 llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, UsedArray.size()); 587 588 llvm::GlobalVariable *GV = 589 new llvm::GlobalVariable(getModule(), ATy, false, 590 llvm::GlobalValue::AppendingLinkage, 591 llvm::ConstantArray::get(ATy, UsedArray), 592 "llvm.used"); 593 594 GV->setSection("llvm.metadata"); 595} 596 597void CodeGenModule::EmitDeferred() { 598 // Emit code for any potentially referenced deferred decls. Since a 599 // previously unused static decl may become used during the generation of code 600 // for a static function, iterate until no changes are made. 601 602 while (!DeferredDeclsToEmit.empty() || !DeferredVTables.empty()) { 603 if (!DeferredVTables.empty()) { 604 const CXXRecordDecl *RD = DeferredVTables.back(); 605 DeferredVTables.pop_back(); 606 getVTables().GenerateClassData(getVTableLinkage(RD), RD); 607 continue; 608 } 609 610 GlobalDecl D = DeferredDeclsToEmit.back(); 611 DeferredDeclsToEmit.pop_back(); 612 613 // Check to see if we've already emitted this. This is necessary 614 // for a couple of reasons: first, decls can end up in the 615 // deferred-decls queue multiple times, and second, decls can end 616 // up with definitions in unusual ways (e.g. by an extern inline 617 // function acquiring a strong function redefinition). Just 618 // ignore these cases. 619 // 620 // TODO: That said, looking this up multiple times is very wasteful. 621 llvm::StringRef Name = getMangledName(D); 622 llvm::GlobalValue *CGRef = GetGlobalValue(Name); 623 assert(CGRef && "Deferred decl wasn't referenced?"); 624 625 if (!CGRef->isDeclaration()) 626 continue; 627 628 // GlobalAlias::isDeclaration() defers to the aliasee, but for our 629 // purposes an alias counts as a definition. 630 if (isa<llvm::GlobalAlias>(CGRef)) 631 continue; 632 633 // Otherwise, emit the definition and move on to the next one. 634 EmitGlobalDefinition(D); 635 } 636} 637 638/// EmitAnnotateAttr - Generate the llvm::ConstantStruct which contains the 639/// annotation information for a given GlobalValue. The annotation struct is 640/// {i8 *, i8 *, i8 *, i32}. The first field is a constant expression, the 641/// GlobalValue being annotated. The second field is the constant string 642/// created from the AnnotateAttr's annotation. The third field is a constant 643/// string containing the name of the translation unit. The fourth field is 644/// the line number in the file of the annotated value declaration. 645/// 646/// FIXME: this does not unique the annotation string constants, as llvm-gcc 647/// appears to. 648/// 649llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 650 const AnnotateAttr *AA, 651 unsigned LineNo) { 652 llvm::Module *M = &getModule(); 653 654 // get [N x i8] constants for the annotation string, and the filename string 655 // which are the 2nd and 3rd elements of the global annotation structure. 656 const llvm::Type *SBP = llvm::Type::getInt8PtrTy(VMContext); 657 llvm::Constant *anno = llvm::ConstantArray::get(VMContext, 658 AA->getAnnotation(), true); 659 llvm::Constant *unit = llvm::ConstantArray::get(VMContext, 660 M->getModuleIdentifier(), 661 true); 662 663 // Get the two global values corresponding to the ConstantArrays we just 664 // created to hold the bytes of the strings. 665 llvm::GlobalValue *annoGV = 666 new llvm::GlobalVariable(*M, anno->getType(), false, 667 llvm::GlobalValue::PrivateLinkage, anno, 668 GV->getName()); 669 // translation unit name string, emitted into the llvm.metadata section. 670 llvm::GlobalValue *unitGV = 671 new llvm::GlobalVariable(*M, unit->getType(), false, 672 llvm::GlobalValue::PrivateLinkage, unit, 673 ".str"); 674 unitGV->setUnnamedAddr(true); 675 676 // Create the ConstantStruct for the global annotation. 677 llvm::Constant *Fields[4] = { 678 llvm::ConstantExpr::getBitCast(GV, SBP), 679 llvm::ConstantExpr::getBitCast(annoGV, SBP), 680 llvm::ConstantExpr::getBitCast(unitGV, SBP), 681 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), LineNo) 682 }; 683 return llvm::ConstantStruct::getAnon(Fields); 684} 685 686bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) { 687 // Never defer when EmitAllDecls is specified. 688 if (Features.EmitAllDecls) 689 return false; 690 691 return !getContext().DeclMustBeEmitted(Global); 692} 693 694llvm::Constant *CodeGenModule::GetWeakRefReference(const ValueDecl *VD) { 695 const AliasAttr *AA = VD->getAttr<AliasAttr>(); 696 assert(AA && "No alias?"); 697 698 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType()); 699 700 // See if there is already something with the target's name in the module. 701 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee()); 702 703 llvm::Constant *Aliasee; 704 if (isa<llvm::FunctionType>(DeclTy)) 705 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GlobalDecl(), 706 /*ForVTable=*/false); 707 else 708 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), 709 llvm::PointerType::getUnqual(DeclTy), 0); 710 if (!Entry) { 711 llvm::GlobalValue* F = cast<llvm::GlobalValue>(Aliasee); 712 F->setLinkage(llvm::Function::ExternalWeakLinkage); 713 WeakRefReferences.insert(F); 714 } 715 716 return Aliasee; 717} 718 719void CodeGenModule::EmitGlobal(GlobalDecl GD) { 720 const ValueDecl *Global = cast<ValueDecl>(GD.getDecl()); 721 722 // Weak references don't produce any output by themselves. 723 if (Global->hasAttr<WeakRefAttr>()) 724 return; 725 726 // If this is an alias definition (which otherwise looks like a declaration) 727 // emit it now. 728 if (Global->hasAttr<AliasAttr>()) 729 return EmitAliasDefinition(GD); 730 731 // Ignore declarations, they will be emitted on their first use. 732 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) { 733 if (FD->getIdentifier()) { 734 llvm::StringRef Name = FD->getName(); 735 if (Name == "_Block_object_assign") { 736 BlockObjectAssignDecl = FD; 737 } else if (Name == "_Block_object_dispose") { 738 BlockObjectDisposeDecl = FD; 739 } 740 } 741 742 // Forward declarations are emitted lazily on first use. 743 if (!FD->doesThisDeclarationHaveABody()) { 744 if (!FD->doesDeclarationForceExternallyVisibleDefinition()) 745 return; 746 747 const FunctionDecl *InlineDefinition = 0; 748 FD->getBody(InlineDefinition); 749 750 llvm::StringRef MangledName = getMangledName(GD); 751 llvm::StringMap<GlobalDecl>::iterator DDI = 752 DeferredDecls.find(MangledName); 753 if (DDI != DeferredDecls.end()) 754 DeferredDecls.erase(DDI); 755 EmitGlobalDefinition(InlineDefinition); 756 return; 757 } 758 } else { 759 const VarDecl *VD = cast<VarDecl>(Global); 760 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 761 762 if (VD->getIdentifier()) { 763 llvm::StringRef Name = VD->getName(); 764 if (Name == "_NSConcreteGlobalBlock") { 765 NSConcreteGlobalBlockDecl = VD; 766 } else if (Name == "_NSConcreteStackBlock") { 767 NSConcreteStackBlockDecl = VD; 768 } 769 } 770 771 772 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) 773 return; 774 } 775 776 // Defer code generation when possible if this is a static definition, inline 777 // function etc. These we only want to emit if they are used. 778 if (!MayDeferGeneration(Global)) { 779 // Emit the definition if it can't be deferred. 780 EmitGlobalDefinition(GD); 781 return; 782 } 783 784 // If we're deferring emission of a C++ variable with an 785 // initializer, remember the order in which it appeared in the file. 786 if (getLangOptions().CPlusPlus && isa<VarDecl>(Global) && 787 cast<VarDecl>(Global)->hasInit()) { 788 DelayedCXXInitPosition[Global] = CXXGlobalInits.size(); 789 CXXGlobalInits.push_back(0); 790 } 791 792 // If the value has already been used, add it directly to the 793 // DeferredDeclsToEmit list. 794 llvm::StringRef MangledName = getMangledName(GD); 795 if (GetGlobalValue(MangledName)) 796 DeferredDeclsToEmit.push_back(GD); 797 else { 798 // Otherwise, remember that we saw a deferred decl with this name. The 799 // first use of the mangled name will cause it to move into 800 // DeferredDeclsToEmit. 801 DeferredDecls[MangledName] = GD; 802 } 803} 804 805void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) { 806 const ValueDecl *D = cast<ValueDecl>(GD.getDecl()); 807 808 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(), 809 Context.getSourceManager(), 810 "Generating code for declaration"); 811 812 if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 813 // At -O0, don't generate IR for functions with available_externally 814 // linkage. 815 if (CodeGenOpts.OptimizationLevel == 0 && 816 !Function->hasAttr<AlwaysInlineAttr>() && 817 getFunctionLinkage(Function) 818 == llvm::Function::AvailableExternallyLinkage) 819 return; 820 821 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 822 // Make sure to emit the definition(s) before we emit the thunks. 823 // This is necessary for the generation of certain thunks. 824 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Method)) 825 EmitCXXConstructor(CD, GD.getCtorType()); 826 else if (const CXXDestructorDecl *DD =dyn_cast<CXXDestructorDecl>(Method)) 827 EmitCXXDestructor(DD, GD.getDtorType()); 828 else 829 EmitGlobalFunctionDefinition(GD); 830 831 if (Method->isVirtual()) 832 getVTables().EmitThunks(GD); 833 834 return; 835 } 836 837 return EmitGlobalFunctionDefinition(GD); 838 } 839 840 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 841 return EmitGlobalVarDefinition(VD); 842 843 assert(0 && "Invalid argument to EmitGlobalDefinition()"); 844} 845 846/// GetOrCreateLLVMFunction - If the specified mangled name is not in the 847/// module, create and return an llvm Function with the specified type. If there 848/// is something in the module with the specified name, return it potentially 849/// bitcasted to the right type. 850/// 851/// If D is non-null, it specifies a decl that correspond to this. This is used 852/// to set the attributes on the function when it is first created. 853llvm::Constant * 854CodeGenModule::GetOrCreateLLVMFunction(llvm::StringRef MangledName, 855 const llvm::Type *Ty, 856 GlobalDecl D, bool ForVTable, 857 llvm::Attributes ExtraAttrs) { 858 // Lookup the entry, lazily creating it if necessary. 859 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 860 if (Entry) { 861 if (WeakRefReferences.count(Entry)) { 862 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl()); 863 if (FD && !FD->hasAttr<WeakAttr>()) 864 Entry->setLinkage(llvm::Function::ExternalLinkage); 865 866 WeakRefReferences.erase(Entry); 867 } 868 869 if (Entry->getType()->getElementType() == Ty) 870 return Entry; 871 872 // Make sure the result is of the correct type. 873 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 874 return llvm::ConstantExpr::getBitCast(Entry, PTy); 875 } 876 877 // This function doesn't have a complete type (for example, the return 878 // type is an incomplete struct). Use a fake type instead, and make 879 // sure not to try to set attributes. 880 bool IsIncompleteFunction = false; 881 882 const llvm::FunctionType *FTy; 883 if (isa<llvm::FunctionType>(Ty)) { 884 FTy = cast<llvm::FunctionType>(Ty); 885 } else { 886 FTy = llvm::FunctionType::get(VoidTy, false); 887 IsIncompleteFunction = true; 888 } 889 890 llvm::Function *F = llvm::Function::Create(FTy, 891 llvm::Function::ExternalLinkage, 892 MangledName, &getModule()); 893 assert(F->getName() == MangledName && "name was uniqued!"); 894 if (D.getDecl()) 895 SetFunctionAttributes(D, F, IsIncompleteFunction); 896 if (ExtraAttrs != llvm::Attribute::None) 897 F->addFnAttr(ExtraAttrs); 898 899 // This is the first use or definition of a mangled name. If there is a 900 // deferred decl with this name, remember that we need to emit it at the end 901 // of the file. 902 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName); 903 if (DDI != DeferredDecls.end()) { 904 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 905 // list, and remove it from DeferredDecls (since we don't need it anymore). 906 DeferredDeclsToEmit.push_back(DDI->second); 907 DeferredDecls.erase(DDI); 908 909 // Otherwise, there are cases we have to worry about where we're 910 // using a declaration for which we must emit a definition but where 911 // we might not find a top-level definition: 912 // - member functions defined inline in their classes 913 // - friend functions defined inline in some class 914 // - special member functions with implicit definitions 915 // If we ever change our AST traversal to walk into class methods, 916 // this will be unnecessary. 917 // 918 // We also don't emit a definition for a function if it's going to be an entry 919 // in a vtable, unless it's already marked as used. 920 } else if (getLangOptions().CPlusPlus && D.getDecl()) { 921 // Look for a declaration that's lexically in a record. 922 const FunctionDecl *FD = cast<FunctionDecl>(D.getDecl()); 923 do { 924 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) { 925 if (FD->isImplicit() && !ForVTable) { 926 assert(FD->isUsed() && "Sema didn't mark implicit function as used!"); 927 DeferredDeclsToEmit.push_back(D.getWithDecl(FD)); 928 break; 929 } else if (FD->doesThisDeclarationHaveABody()) { 930 DeferredDeclsToEmit.push_back(D.getWithDecl(FD)); 931 break; 932 } 933 } 934 FD = FD->getPreviousDeclaration(); 935 } while (FD); 936 } 937 938 // Make sure the result is of the requested type. 939 if (!IsIncompleteFunction) { 940 assert(F->getType()->getElementType() == Ty); 941 return F; 942 } 943 944 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 945 return llvm::ConstantExpr::getBitCast(F, PTy); 946} 947 948/// GetAddrOfFunction - Return the address of the given function. If Ty is 949/// non-null, then this function will use the specified type if it has to 950/// create it (this occurs when we see a definition of the function). 951llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD, 952 const llvm::Type *Ty, 953 bool ForVTable) { 954 // If there was no specific requested type, just convert it now. 955 if (!Ty) 956 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType()); 957 958 llvm::StringRef MangledName = getMangledName(GD); 959 return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable); 960} 961 962/// CreateRuntimeFunction - Create a new runtime function with the specified 963/// type and name. 964llvm::Constant * 965CodeGenModule::CreateRuntimeFunction(const llvm::FunctionType *FTy, 966 llvm::StringRef Name, 967 llvm::Attributes ExtraAttrs) { 968 return GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false, 969 ExtraAttrs); 970} 971 972static bool DeclIsConstantGlobal(ASTContext &Context, const VarDecl *D, 973 bool ConstantInit) { 974 if (!D->getType().isConstant(Context) && !D->getType()->isReferenceType()) 975 return false; 976 977 if (Context.getLangOptions().CPlusPlus) { 978 if (const RecordType *Record 979 = Context.getBaseElementType(D->getType())->getAs<RecordType>()) 980 return ConstantInit && 981 cast<CXXRecordDecl>(Record->getDecl())->isPOD() && 982 !cast<CXXRecordDecl>(Record->getDecl())->hasMutableFields(); 983 } 984 985 return true; 986} 987 988/// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 989/// create and return an llvm GlobalVariable with the specified type. If there 990/// is something in the module with the specified name, return it potentially 991/// bitcasted to the right type. 992/// 993/// If D is non-null, it specifies a decl that correspond to this. This is used 994/// to set the attributes on the global when it is first created. 995llvm::Constant * 996CodeGenModule::GetOrCreateLLVMGlobal(llvm::StringRef MangledName, 997 const llvm::PointerType *Ty, 998 const VarDecl *D, 999 bool UnnamedAddr) { 1000 // Lookup the entry, lazily creating it if necessary. 1001 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 1002 if (Entry) { 1003 if (WeakRefReferences.count(Entry)) { 1004 if (D && !D->hasAttr<WeakAttr>()) 1005 Entry->setLinkage(llvm::Function::ExternalLinkage); 1006 1007 WeakRefReferences.erase(Entry); 1008 } 1009 1010 if (UnnamedAddr) 1011 Entry->setUnnamedAddr(true); 1012 1013 if (Entry->getType() == Ty) 1014 return Entry; 1015 1016 // Make sure the result is of the correct type. 1017 return llvm::ConstantExpr::getBitCast(Entry, Ty); 1018 } 1019 1020 // This is the first use or definition of a mangled name. If there is a 1021 // deferred decl with this name, remember that we need to emit it at the end 1022 // of the file. 1023 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName); 1024 if (DDI != DeferredDecls.end()) { 1025 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 1026 // list, and remove it from DeferredDecls (since we don't need it anymore). 1027 DeferredDeclsToEmit.push_back(DDI->second); 1028 DeferredDecls.erase(DDI); 1029 } 1030 1031 llvm::GlobalVariable *GV = 1032 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false, 1033 llvm::GlobalValue::ExternalLinkage, 1034 0, MangledName, 0, 1035 false, Ty->getAddressSpace()); 1036 1037 // Handle things which are present even on external declarations. 1038 if (D) { 1039 // FIXME: This code is overly simple and should be merged with other global 1040 // handling. 1041 GV->setConstant(DeclIsConstantGlobal(Context, D, false)); 1042 1043 // Set linkage and visibility in case we never see a definition. 1044 NamedDecl::LinkageInfo LV = D->getLinkageAndVisibility(); 1045 if (LV.linkage() != ExternalLinkage) { 1046 // Don't set internal linkage on declarations. 1047 } else { 1048 if (D->hasAttr<DLLImportAttr>()) 1049 GV->setLinkage(llvm::GlobalValue::DLLImportLinkage); 1050 else if (D->hasAttr<WeakAttr>() || D->isWeakImported()) 1051 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 1052 1053 // Set visibility on a declaration only if it's explicit. 1054 if (LV.visibilityExplicit()) 1055 GV->setVisibility(GetLLVMVisibility(LV.visibility())); 1056 } 1057 1058 GV->setThreadLocal(D->isThreadSpecified()); 1059 } 1060 1061 return GV; 1062} 1063 1064 1065llvm::GlobalVariable * 1066CodeGenModule::CreateOrReplaceCXXRuntimeVariable(llvm::StringRef Name, 1067 const llvm::Type *Ty, 1068 llvm::GlobalValue::LinkageTypes Linkage) { 1069 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name); 1070 llvm::GlobalVariable *OldGV = 0; 1071 1072 1073 if (GV) { 1074 // Check if the variable has the right type. 1075 if (GV->getType()->getElementType() == Ty) 1076 return GV; 1077 1078 // Because C++ name mangling, the only way we can end up with an already 1079 // existing global with the same name is if it has been declared extern "C". 1080 assert(GV->isDeclaration() && "Declaration has wrong type!"); 1081 OldGV = GV; 1082 } 1083 1084 // Create a new variable. 1085 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true, 1086 Linkage, 0, Name); 1087 1088 if (OldGV) { 1089 // Replace occurrences of the old variable if needed. 1090 GV->takeName(OldGV); 1091 1092 if (!OldGV->use_empty()) { 1093 llvm::Constant *NewPtrForOldDecl = 1094 llvm::ConstantExpr::getBitCast(GV, OldGV->getType()); 1095 OldGV->replaceAllUsesWith(NewPtrForOldDecl); 1096 } 1097 1098 OldGV->eraseFromParent(); 1099 } 1100 1101 return GV; 1102} 1103 1104/// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 1105/// given global variable. If Ty is non-null and if the global doesn't exist, 1106/// then it will be greated with the specified type instead of whatever the 1107/// normal requested type would be. 1108llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 1109 const llvm::Type *Ty) { 1110 assert(D->hasGlobalStorage() && "Not a global variable"); 1111 QualType ASTTy = D->getType(); 1112 if (Ty == 0) 1113 Ty = getTypes().ConvertTypeForMem(ASTTy); 1114 1115 const llvm::PointerType *PTy = 1116 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy)); 1117 1118 llvm::StringRef MangledName = getMangledName(D); 1119 return GetOrCreateLLVMGlobal(MangledName, PTy, D); 1120} 1121 1122/// CreateRuntimeVariable - Create a new runtime global variable with the 1123/// specified type and name. 1124llvm::Constant * 1125CodeGenModule::CreateRuntimeVariable(const llvm::Type *Ty, 1126 llvm::StringRef Name) { 1127 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0, 1128 true); 1129} 1130 1131void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 1132 assert(!D->getInit() && "Cannot emit definite definitions here!"); 1133 1134 if (MayDeferGeneration(D)) { 1135 // If we have not seen a reference to this variable yet, place it 1136 // into the deferred declarations table to be emitted if needed 1137 // later. 1138 llvm::StringRef MangledName = getMangledName(D); 1139 if (!GetGlobalValue(MangledName)) { 1140 DeferredDecls[MangledName] = D; 1141 return; 1142 } 1143 } 1144 1145 // The tentative definition is the only definition. 1146 EmitGlobalVarDefinition(D); 1147} 1148 1149void CodeGenModule::EmitVTable(CXXRecordDecl *Class, bool DefinitionRequired) { 1150 if (DefinitionRequired) 1151 getVTables().GenerateClassData(getVTableLinkage(Class), Class); 1152} 1153 1154llvm::GlobalVariable::LinkageTypes 1155CodeGenModule::getVTableLinkage(const CXXRecordDecl *RD) { 1156 if (RD->getLinkage() != ExternalLinkage) 1157 return llvm::GlobalVariable::InternalLinkage; 1158 1159 if (const CXXMethodDecl *KeyFunction 1160 = RD->getASTContext().getKeyFunction(RD)) { 1161 // If this class has a key function, use that to determine the linkage of 1162 // the vtable. 1163 const FunctionDecl *Def = 0; 1164 if (KeyFunction->hasBody(Def)) 1165 KeyFunction = cast<CXXMethodDecl>(Def); 1166 1167 switch (KeyFunction->getTemplateSpecializationKind()) { 1168 case TSK_Undeclared: 1169 case TSK_ExplicitSpecialization: 1170 // When compiling with optimizations turned on, we emit all vtables, 1171 // even if the key function is not defined in the current translation 1172 // unit. If this is the case, use available_externally linkage. 1173 if (!Def && CodeGenOpts.OptimizationLevel) 1174 return llvm::GlobalVariable::AvailableExternallyLinkage; 1175 1176 if (KeyFunction->isInlined()) 1177 return !Context.getLangOptions().AppleKext ? 1178 llvm::GlobalVariable::LinkOnceODRLinkage : 1179 llvm::Function::InternalLinkage; 1180 1181 return llvm::GlobalVariable::ExternalLinkage; 1182 1183 case TSK_ImplicitInstantiation: 1184 return !Context.getLangOptions().AppleKext ? 1185 llvm::GlobalVariable::LinkOnceODRLinkage : 1186 llvm::Function::InternalLinkage; 1187 1188 case TSK_ExplicitInstantiationDefinition: 1189 return !Context.getLangOptions().AppleKext ? 1190 llvm::GlobalVariable::WeakODRLinkage : 1191 llvm::Function::InternalLinkage; 1192 1193 case TSK_ExplicitInstantiationDeclaration: 1194 // FIXME: Use available_externally linkage. However, this currently 1195 // breaks LLVM's build due to undefined symbols. 1196 // return llvm::GlobalVariable::AvailableExternallyLinkage; 1197 return !Context.getLangOptions().AppleKext ? 1198 llvm::GlobalVariable::LinkOnceODRLinkage : 1199 llvm::Function::InternalLinkage; 1200 } 1201 } 1202 1203 if (Context.getLangOptions().AppleKext) 1204 return llvm::Function::InternalLinkage; 1205 1206 switch (RD->getTemplateSpecializationKind()) { 1207 case TSK_Undeclared: 1208 case TSK_ExplicitSpecialization: 1209 case TSK_ImplicitInstantiation: 1210 // FIXME: Use available_externally linkage. However, this currently 1211 // breaks LLVM's build due to undefined symbols. 1212 // return llvm::GlobalVariable::AvailableExternallyLinkage; 1213 case TSK_ExplicitInstantiationDeclaration: 1214 return llvm::GlobalVariable::LinkOnceODRLinkage; 1215 1216 case TSK_ExplicitInstantiationDefinition: 1217 return llvm::GlobalVariable::WeakODRLinkage; 1218 } 1219 1220 // Silence GCC warning. 1221 return llvm::GlobalVariable::LinkOnceODRLinkage; 1222} 1223 1224CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const { 1225 return Context.toCharUnitsFromBits( 1226 TheTargetData.getTypeStoreSizeInBits(Ty)); 1227} 1228 1229void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { 1230 llvm::Constant *Init = 0; 1231 QualType ASTTy = D->getType(); 1232 bool NonConstInit = false; 1233 1234 const Expr *InitExpr = D->getAnyInitializer(); 1235 1236 if (!InitExpr) { 1237 // This is a tentative definition; tentative definitions are 1238 // implicitly initialized with { 0 }. 1239 // 1240 // Note that tentative definitions are only emitted at the end of 1241 // a translation unit, so they should never have incomplete 1242 // type. In addition, EmitTentativeDefinition makes sure that we 1243 // never attempt to emit a tentative definition if a real one 1244 // exists. A use may still exists, however, so we still may need 1245 // to do a RAUW. 1246 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 1247 Init = EmitNullConstant(D->getType()); 1248 } else { 1249 Init = EmitConstantExpr(InitExpr, D->getType()); 1250 if (!Init) { 1251 QualType T = InitExpr->getType(); 1252 if (D->getType()->isReferenceType()) 1253 T = D->getType(); 1254 1255 if (getLangOptions().CPlusPlus) { 1256 Init = EmitNullConstant(T); 1257 NonConstInit = true; 1258 } else { 1259 ErrorUnsupported(D, "static initializer"); 1260 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 1261 } 1262 } else { 1263 // We don't need an initializer, so remove the entry for the delayed 1264 // initializer position (just in case this entry was delayed). 1265 if (getLangOptions().CPlusPlus) 1266 DelayedCXXInitPosition.erase(D); 1267 } 1268 } 1269 1270 const llvm::Type* InitType = Init->getType(); 1271 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType); 1272 1273 // Strip off a bitcast if we got one back. 1274 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1275 assert(CE->getOpcode() == llvm::Instruction::BitCast || 1276 // all zero index gep. 1277 CE->getOpcode() == llvm::Instruction::GetElementPtr); 1278 Entry = CE->getOperand(0); 1279 } 1280 1281 // Entry is now either a Function or GlobalVariable. 1282 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry); 1283 1284 // We have a definition after a declaration with the wrong type. 1285 // We must make a new GlobalVariable* and update everything that used OldGV 1286 // (a declaration or tentative definition) with the new GlobalVariable* 1287 // (which will be a definition). 1288 // 1289 // This happens if there is a prototype for a global (e.g. 1290 // "extern int x[];") and then a definition of a different type (e.g. 1291 // "int x[10];"). This also happens when an initializer has a different type 1292 // from the type of the global (this happens with unions). 1293 if (GV == 0 || 1294 GV->getType()->getElementType() != InitType || 1295 GV->getType()->getAddressSpace() != 1296 getContext().getTargetAddressSpace(ASTTy)) { 1297 1298 // Move the old entry aside so that we'll create a new one. 1299 Entry->setName(llvm::StringRef()); 1300 1301 // Make a new global with the correct type, this is now guaranteed to work. 1302 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType)); 1303 1304 // Replace all uses of the old global with the new global 1305 llvm::Constant *NewPtrForOldDecl = 1306 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 1307 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1308 1309 // Erase the old global, since it is no longer used. 1310 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 1311 } 1312 1313 if (const AnnotateAttr *AA = D->getAttr<AnnotateAttr>()) { 1314 SourceManager &SM = Context.getSourceManager(); 1315 AddAnnotation(EmitAnnotateAttr(GV, AA, 1316 SM.getInstantiationLineNumber(D->getLocation()))); 1317 } 1318 1319 GV->setInitializer(Init); 1320 1321 // If it is safe to mark the global 'constant', do so now. 1322 GV->setConstant(false); 1323 if (!NonConstInit && DeclIsConstantGlobal(Context, D, true)) 1324 GV->setConstant(true); 1325 1326 GV->setAlignment(getContext().getDeclAlign(D).getQuantity()); 1327 1328 // Set the llvm linkage type as appropriate. 1329 llvm::GlobalValue::LinkageTypes Linkage = 1330 GetLLVMLinkageVarDefinition(D, GV); 1331 GV->setLinkage(Linkage); 1332 if (Linkage == llvm::GlobalVariable::CommonLinkage) 1333 // common vars aren't constant even if declared const. 1334 GV->setConstant(false); 1335 1336 SetCommonAttributes(D, GV); 1337 1338 // Emit the initializer function if necessary. 1339 if (NonConstInit) 1340 EmitCXXGlobalVarDeclInitFunc(D, GV); 1341 1342 // Emit global variable debug information. 1343 if (CGDebugInfo *DI = getModuleDebugInfo()) { 1344 DI->setLocation(D->getLocation()); 1345 DI->EmitGlobalVariable(GV, D); 1346 } 1347} 1348 1349llvm::GlobalValue::LinkageTypes 1350CodeGenModule::GetLLVMLinkageVarDefinition(const VarDecl *D, 1351 llvm::GlobalVariable *GV) { 1352 GVALinkage Linkage = getContext().GetGVALinkageForVariable(D); 1353 if (Linkage == GVA_Internal) 1354 return llvm::Function::InternalLinkage; 1355 else if (D->hasAttr<DLLImportAttr>()) 1356 return llvm::Function::DLLImportLinkage; 1357 else if (D->hasAttr<DLLExportAttr>()) 1358 return llvm::Function::DLLExportLinkage; 1359 else if (D->hasAttr<WeakAttr>()) { 1360 if (GV->isConstant()) 1361 return llvm::GlobalVariable::WeakODRLinkage; 1362 else 1363 return llvm::GlobalVariable::WeakAnyLinkage; 1364 } else if (Linkage == GVA_TemplateInstantiation || 1365 Linkage == GVA_ExplicitTemplateInstantiation) 1366 return llvm::GlobalVariable::WeakODRLinkage; 1367 else if (!getLangOptions().CPlusPlus && 1368 ((!CodeGenOpts.NoCommon && !D->getAttr<NoCommonAttr>()) || 1369 D->getAttr<CommonAttr>()) && 1370 !D->hasExternalStorage() && !D->getInit() && 1371 !D->getAttr<SectionAttr>() && !D->isThreadSpecified() && 1372 !D->getAttr<WeakImportAttr>()) { 1373 // Thread local vars aren't considered common linkage. 1374 return llvm::GlobalVariable::CommonLinkage; 1375 } 1376 return llvm::GlobalVariable::ExternalLinkage; 1377} 1378 1379/// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 1380/// implement a function with no prototype, e.g. "int foo() {}". If there are 1381/// existing call uses of the old function in the module, this adjusts them to 1382/// call the new function directly. 1383/// 1384/// This is not just a cleanup: the always_inline pass requires direct calls to 1385/// functions to be able to inline them. If there is a bitcast in the way, it 1386/// won't inline them. Instcombine normally deletes these calls, but it isn't 1387/// run at -O0. 1388static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 1389 llvm::Function *NewFn) { 1390 // If we're redefining a global as a function, don't transform it. 1391 llvm::Function *OldFn = dyn_cast<llvm::Function>(Old); 1392 if (OldFn == 0) return; 1393 1394 const llvm::Type *NewRetTy = NewFn->getReturnType(); 1395 llvm::SmallVector<llvm::Value*, 4> ArgList; 1396 1397 for (llvm::Value::use_iterator UI = OldFn->use_begin(), E = OldFn->use_end(); 1398 UI != E; ) { 1399 // TODO: Do invokes ever occur in C code? If so, we should handle them too. 1400 llvm::Value::use_iterator I = UI++; // Increment before the CI is erased. 1401 llvm::CallInst *CI = dyn_cast<llvm::CallInst>(*I); 1402 if (!CI) continue; // FIXME: when we allow Invoke, just do CallSite CS(*I) 1403 llvm::CallSite CS(CI); 1404 if (!CI || !CS.isCallee(I)) continue; 1405 1406 // If the return types don't match exactly, and if the call isn't dead, then 1407 // we can't transform this call. 1408 if (CI->getType() != NewRetTy && !CI->use_empty()) 1409 continue; 1410 1411 // If the function was passed too few arguments, don't transform. If extra 1412 // arguments were passed, we silently drop them. If any of the types 1413 // mismatch, we don't transform. 1414 unsigned ArgNo = 0; 1415 bool DontTransform = false; 1416 for (llvm::Function::arg_iterator AI = NewFn->arg_begin(), 1417 E = NewFn->arg_end(); AI != E; ++AI, ++ArgNo) { 1418 if (CS.arg_size() == ArgNo || 1419 CS.getArgument(ArgNo)->getType() != AI->getType()) { 1420 DontTransform = true; 1421 break; 1422 } 1423 } 1424 if (DontTransform) 1425 continue; 1426 1427 // Okay, we can transform this. Create the new call instruction and copy 1428 // over the required information. 1429 ArgList.append(CS.arg_begin(), CS.arg_begin() + ArgNo); 1430 llvm::CallInst *NewCall = llvm::CallInst::Create(NewFn, ArgList.begin(), 1431 ArgList.end(), "", CI); 1432 ArgList.clear(); 1433 if (!NewCall->getType()->isVoidTy()) 1434 NewCall->takeName(CI); 1435 NewCall->setAttributes(CI->getAttributes()); 1436 NewCall->setCallingConv(CI->getCallingConv()); 1437 1438 // Finally, remove the old call, replacing any uses with the new one. 1439 if (!CI->use_empty()) 1440 CI->replaceAllUsesWith(NewCall); 1441 1442 // Copy debug location attached to CI. 1443 if (!CI->getDebugLoc().isUnknown()) 1444 NewCall->setDebugLoc(CI->getDebugLoc()); 1445 CI->eraseFromParent(); 1446 } 1447} 1448 1449 1450void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) { 1451 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl()); 1452 1453 // Compute the function info and LLVM type. 1454 const CGFunctionInfo &FI = getTypes().getFunctionInfo(GD); 1455 bool variadic = false; 1456 if (const FunctionProtoType *fpt = D->getType()->getAs<FunctionProtoType>()) 1457 variadic = fpt->isVariadic(); 1458 const llvm::FunctionType *Ty = getTypes().GetFunctionType(FI, variadic, false); 1459 1460 // Get or create the prototype for the function. 1461 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty); 1462 1463 // Strip off a bitcast if we got one back. 1464 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1465 assert(CE->getOpcode() == llvm::Instruction::BitCast); 1466 Entry = CE->getOperand(0); 1467 } 1468 1469 1470 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) { 1471 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry); 1472 1473 // If the types mismatch then we have to rewrite the definition. 1474 assert(OldFn->isDeclaration() && 1475 "Shouldn't replace non-declaration"); 1476 1477 // F is the Function* for the one with the wrong type, we must make a new 1478 // Function* and update everything that used F (a declaration) with the new 1479 // Function* (which will be a definition). 1480 // 1481 // This happens if there is a prototype for a function 1482 // (e.g. "int f()") and then a definition of a different type 1483 // (e.g. "int f(int x)"). Move the old function aside so that it 1484 // doesn't interfere with GetAddrOfFunction. 1485 OldFn->setName(llvm::StringRef()); 1486 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty)); 1487 1488 // If this is an implementation of a function without a prototype, try to 1489 // replace any existing uses of the function (which may be calls) with uses 1490 // of the new function 1491 if (D->getType()->isFunctionNoProtoType()) { 1492 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn); 1493 OldFn->removeDeadConstantUsers(); 1494 } 1495 1496 // Replace uses of F with the Function we will endow with a body. 1497 if (!Entry->use_empty()) { 1498 llvm::Constant *NewPtrForOldDecl = 1499 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType()); 1500 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1501 } 1502 1503 // Ok, delete the old function now, which is dead. 1504 OldFn->eraseFromParent(); 1505 1506 Entry = NewFn; 1507 } 1508 1509 // We need to set linkage and visibility on the function before 1510 // generating code for it because various parts of IR generation 1511 // want to propagate this information down (e.g. to local static 1512 // declarations). 1513 llvm::Function *Fn = cast<llvm::Function>(Entry); 1514 setFunctionLinkage(D, Fn); 1515 1516 // FIXME: this is redundant with part of SetFunctionDefinitionAttributes 1517 setGlobalVisibility(Fn, D); 1518 1519 CodeGenFunction(*this).GenerateCode(D, Fn, FI); 1520 1521 SetFunctionDefinitionAttributes(D, Fn); 1522 SetLLVMFunctionAttributesForDefinition(D, Fn); 1523 1524 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 1525 AddGlobalCtor(Fn, CA->getPriority()); 1526 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 1527 AddGlobalDtor(Fn, DA->getPriority()); 1528} 1529 1530void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) { 1531 const ValueDecl *D = cast<ValueDecl>(GD.getDecl()); 1532 const AliasAttr *AA = D->getAttr<AliasAttr>(); 1533 assert(AA && "Not an alias?"); 1534 1535 llvm::StringRef MangledName = getMangledName(GD); 1536 1537 // If there is a definition in the module, then it wins over the alias. 1538 // This is dubious, but allow it to be safe. Just ignore the alias. 1539 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 1540 if (Entry && !Entry->isDeclaration()) 1541 return; 1542 1543 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 1544 1545 // Create a reference to the named value. This ensures that it is emitted 1546 // if a deferred decl. 1547 llvm::Constant *Aliasee; 1548 if (isa<llvm::FunctionType>(DeclTy)) 1549 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GlobalDecl(), 1550 /*ForVTable=*/false); 1551 else 1552 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), 1553 llvm::PointerType::getUnqual(DeclTy), 0); 1554 1555 // Create the new alias itself, but don't set a name yet. 1556 llvm::GlobalValue *GA = 1557 new llvm::GlobalAlias(Aliasee->getType(), 1558 llvm::Function::ExternalLinkage, 1559 "", Aliasee, &getModule()); 1560 1561 if (Entry) { 1562 assert(Entry->isDeclaration()); 1563 1564 // If there is a declaration in the module, then we had an extern followed 1565 // by the alias, as in: 1566 // extern int test6(); 1567 // ... 1568 // int test6() __attribute__((alias("test7"))); 1569 // 1570 // Remove it and replace uses of it with the alias. 1571 GA->takeName(Entry); 1572 1573 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA, 1574 Entry->getType())); 1575 Entry->eraseFromParent(); 1576 } else { 1577 GA->setName(MangledName); 1578 } 1579 1580 // Set attributes which are particular to an alias; this is a 1581 // specialization of the attributes which may be set on a global 1582 // variable/function. 1583 if (D->hasAttr<DLLExportAttr>()) { 1584 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1585 // The dllexport attribute is ignored for undefined symbols. 1586 if (FD->hasBody()) 1587 GA->setLinkage(llvm::Function::DLLExportLinkage); 1588 } else { 1589 GA->setLinkage(llvm::Function::DLLExportLinkage); 1590 } 1591 } else if (D->hasAttr<WeakAttr>() || 1592 D->hasAttr<WeakRefAttr>() || 1593 D->isWeakImported()) { 1594 GA->setLinkage(llvm::Function::WeakAnyLinkage); 1595 } 1596 1597 SetCommonAttributes(D, GA); 1598} 1599 1600/// getBuiltinLibFunction - Given a builtin id for a function like 1601/// "__builtin_fabsf", return a Function* for "fabsf". 1602llvm::Value *CodeGenModule::getBuiltinLibFunction(const FunctionDecl *FD, 1603 unsigned BuiltinID) { 1604 assert((Context.BuiltinInfo.isLibFunction(BuiltinID) || 1605 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) && 1606 "isn't a lib fn"); 1607 1608 // Get the name, skip over the __builtin_ prefix (if necessary). 1609 llvm::StringRef Name; 1610 GlobalDecl D(FD); 1611 1612 // If the builtin has been declared explicitly with an assembler label, 1613 // use the mangled name. This differs from the plain label on platforms 1614 // that prefix labels. 1615 if (FD->hasAttr<AsmLabelAttr>()) 1616 Name = getMangledName(D); 1617 else if (Context.BuiltinInfo.isLibFunction(BuiltinID)) 1618 Name = Context.BuiltinInfo.GetName(BuiltinID) + 10; 1619 else 1620 Name = Context.BuiltinInfo.GetName(BuiltinID); 1621 1622 1623 const llvm::FunctionType *Ty = 1624 cast<llvm::FunctionType>(getTypes().ConvertType(FD->getType())); 1625 1626 return GetOrCreateLLVMFunction(Name, Ty, D, /*ForVTable=*/false); 1627} 1628 1629llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,const llvm::Type **Tys, 1630 unsigned NumTys) { 1631 return llvm::Intrinsic::getDeclaration(&getModule(), 1632 (llvm::Intrinsic::ID)IID, Tys, NumTys); 1633} 1634 1635static llvm::StringMapEntry<llvm::Constant*> & 1636GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map, 1637 const StringLiteral *Literal, 1638 bool TargetIsLSB, 1639 bool &IsUTF16, 1640 unsigned &StringLength) { 1641 llvm::StringRef String = Literal->getString(); 1642 unsigned NumBytes = String.size(); 1643 1644 // Check for simple case. 1645 if (!Literal->containsNonAsciiOrNull()) { 1646 StringLength = NumBytes; 1647 return Map.GetOrCreateValue(String); 1648 } 1649 1650 // Otherwise, convert the UTF8 literals into a byte string. 1651 llvm::SmallVector<UTF16, 128> ToBuf(NumBytes); 1652 const UTF8 *FromPtr = (UTF8 *)String.data(); 1653 UTF16 *ToPtr = &ToBuf[0]; 1654 1655 (void)ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, 1656 &ToPtr, ToPtr + NumBytes, 1657 strictConversion); 1658 1659 // ConvertUTF8toUTF16 returns the length in ToPtr. 1660 StringLength = ToPtr - &ToBuf[0]; 1661 1662 // Render the UTF-16 string into a byte array and convert to the target byte 1663 // order. 1664 // 1665 // FIXME: This isn't something we should need to do here. 1666 llvm::SmallString<128> AsBytes; 1667 AsBytes.reserve(StringLength * 2); 1668 for (unsigned i = 0; i != StringLength; ++i) { 1669 unsigned short Val = ToBuf[i]; 1670 if (TargetIsLSB) { 1671 AsBytes.push_back(Val & 0xFF); 1672 AsBytes.push_back(Val >> 8); 1673 } else { 1674 AsBytes.push_back(Val >> 8); 1675 AsBytes.push_back(Val & 0xFF); 1676 } 1677 } 1678 // Append one extra null character, the second is automatically added by our 1679 // caller. 1680 AsBytes.push_back(0); 1681 1682 IsUTF16 = true; 1683 return Map.GetOrCreateValue(llvm::StringRef(AsBytes.data(), AsBytes.size())); 1684} 1685 1686static llvm::StringMapEntry<llvm::Constant*> & 1687GetConstantStringEntry(llvm::StringMap<llvm::Constant*> &Map, 1688 const StringLiteral *Literal, 1689 unsigned &StringLength) 1690{ 1691 llvm::StringRef String = Literal->getString(); 1692 StringLength = String.size(); 1693 return Map.GetOrCreateValue(String); 1694} 1695 1696llvm::Constant * 1697CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 1698 unsigned StringLength = 0; 1699 bool isUTF16 = false; 1700 llvm::StringMapEntry<llvm::Constant*> &Entry = 1701 GetConstantCFStringEntry(CFConstantStringMap, Literal, 1702 getTargetData().isLittleEndian(), 1703 isUTF16, StringLength); 1704 1705 if (llvm::Constant *C = Entry.getValue()) 1706 return C; 1707 1708 llvm::Constant *Zero = 1709 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)); 1710 llvm::Constant *Zeros[] = { Zero, Zero }; 1711 1712 // If we don't already have it, get __CFConstantStringClassReference. 1713 if (!CFConstantStringClassRef) { 1714 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 1715 Ty = llvm::ArrayType::get(Ty, 0); 1716 llvm::Constant *GV = CreateRuntimeVariable(Ty, 1717 "__CFConstantStringClassReference"); 1718 // Decay array -> ptr 1719 CFConstantStringClassRef = 1720 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1721 } 1722 1723 QualType CFTy = getContext().getCFConstantStringType(); 1724 1725 const llvm::StructType *STy = 1726 cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 1727 1728 std::vector<llvm::Constant*> Fields(4); 1729 1730 // Class pointer. 1731 Fields[0] = CFConstantStringClassRef; 1732 1733 // Flags. 1734 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); 1735 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) : 1736 llvm::ConstantInt::get(Ty, 0x07C8); 1737 1738 // String pointer. 1739 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str()); 1740 1741 llvm::GlobalValue::LinkageTypes Linkage; 1742 bool isConstant; 1743 if (isUTF16) { 1744 // FIXME: why do utf strings get "_" labels instead of "L" labels? 1745 Linkage = llvm::GlobalValue::InternalLinkage; 1746 // Note: -fwritable-strings doesn't make unicode CFStrings writable, but 1747 // does make plain ascii ones writable. 1748 isConstant = true; 1749 } else { 1750 // FIXME: With OS X ld 123.2 (xcode 4) and LTO we would get a linker error 1751 // when using private linkage. It is not clear if this is a bug in ld 1752 // or a reasonable new restriction. 1753 Linkage = llvm::GlobalValue::LinkerPrivateLinkage; 1754 isConstant = !Features.WritableStrings; 1755 } 1756 1757 llvm::GlobalVariable *GV = 1758 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C, 1759 ".str"); 1760 GV->setUnnamedAddr(true); 1761 if (isUTF16) { 1762 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy); 1763 GV->setAlignment(Align.getQuantity()); 1764 } else { 1765 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy); 1766 GV->setAlignment(Align.getQuantity()); 1767 } 1768 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1769 1770 // String length. 1771 Ty = getTypes().ConvertType(getContext().LongTy); 1772 Fields[3] = llvm::ConstantInt::get(Ty, StringLength); 1773 1774 // The struct. 1775 C = llvm::ConstantStruct::get(STy, Fields); 1776 GV = new llvm::GlobalVariable(getModule(), C->getType(), true, 1777 llvm::GlobalVariable::PrivateLinkage, C, 1778 "_unnamed_cfstring_"); 1779 if (const char *Sect = getContext().Target.getCFStringSection()) 1780 GV->setSection(Sect); 1781 Entry.setValue(GV); 1782 1783 return GV; 1784} 1785 1786llvm::Constant * 1787CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) { 1788 unsigned StringLength = 0; 1789 llvm::StringMapEntry<llvm::Constant*> &Entry = 1790 GetConstantStringEntry(CFConstantStringMap, Literal, StringLength); 1791 1792 if (llvm::Constant *C = Entry.getValue()) 1793 return C; 1794 1795 llvm::Constant *Zero = 1796 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)); 1797 llvm::Constant *Zeros[] = { Zero, Zero }; 1798 1799 // If we don't already have it, get _NSConstantStringClassReference. 1800 if (!ConstantStringClassRef) { 1801 std::string StringClass(getLangOptions().ObjCConstantStringClass); 1802 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 1803 llvm::Constant *GV; 1804 if (Features.ObjCNonFragileABI) { 1805 std::string str = 1806 StringClass.empty() ? "OBJC_CLASS_$_NSConstantString" 1807 : "OBJC_CLASS_$_" + StringClass; 1808 GV = getObjCRuntime().GetClassGlobal(str); 1809 // Make sure the result is of the correct type. 1810 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 1811 ConstantStringClassRef = 1812 llvm::ConstantExpr::getBitCast(GV, PTy); 1813 } else { 1814 std::string str = 1815 StringClass.empty() ? "_NSConstantStringClassReference" 1816 : "_" + StringClass + "ClassReference"; 1817 const llvm::Type *PTy = llvm::ArrayType::get(Ty, 0); 1818 GV = CreateRuntimeVariable(PTy, str); 1819 // Decay array -> ptr 1820 ConstantStringClassRef = 1821 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1822 } 1823 } 1824 1825 QualType NSTy = getContext().getNSConstantStringType(); 1826 1827 const llvm::StructType *STy = 1828 cast<llvm::StructType>(getTypes().ConvertType(NSTy)); 1829 1830 std::vector<llvm::Constant*> Fields(3); 1831 1832 // Class pointer. 1833 Fields[0] = ConstantStringClassRef; 1834 1835 // String pointer. 1836 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str()); 1837 1838 llvm::GlobalValue::LinkageTypes Linkage; 1839 bool isConstant; 1840 Linkage = llvm::GlobalValue::PrivateLinkage; 1841 isConstant = !Features.WritableStrings; 1842 1843 llvm::GlobalVariable *GV = 1844 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C, 1845 ".str"); 1846 GV->setUnnamedAddr(true); 1847 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy); 1848 GV->setAlignment(Align.getQuantity()); 1849 Fields[1] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1850 1851 // String length. 1852 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); 1853 Fields[2] = llvm::ConstantInt::get(Ty, StringLength); 1854 1855 // The struct. 1856 C = llvm::ConstantStruct::get(STy, Fields); 1857 GV = new llvm::GlobalVariable(getModule(), C->getType(), true, 1858 llvm::GlobalVariable::PrivateLinkage, C, 1859 "_unnamed_nsstring_"); 1860 // FIXME. Fix section. 1861 if (const char *Sect = 1862 Features.ObjCNonFragileABI 1863 ? getContext().Target.getNSStringNonFragileABISection() 1864 : getContext().Target.getNSStringSection()) 1865 GV->setSection(Sect); 1866 Entry.setValue(GV); 1867 1868 return GV; 1869} 1870 1871/// GetStringForStringLiteral - Return the appropriate bytes for a 1872/// string literal, properly padded to match the literal type. 1873std::string CodeGenModule::GetStringForStringLiteral(const StringLiteral *E) { 1874 const ASTContext &Context = getContext(); 1875 const ConstantArrayType *CAT = 1876 Context.getAsConstantArrayType(E->getType()); 1877 assert(CAT && "String isn't pointer or array!"); 1878 1879 // Resize the string to the right size. 1880 uint64_t RealLen = CAT->getSize().getZExtValue(); 1881 1882 if (E->isWide()) 1883 RealLen *= Context.Target.getWCharWidth() / Context.getCharWidth(); 1884 1885 std::string Str = E->getString().str(); 1886 Str.resize(RealLen, '\0'); 1887 1888 return Str; 1889} 1890 1891/// GetAddrOfConstantStringFromLiteral - Return a pointer to a 1892/// constant array for the given string literal. 1893llvm::Constant * 1894CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) { 1895 // FIXME: This can be more efficient. 1896 // FIXME: We shouldn't need to bitcast the constant in the wide string case. 1897 llvm::Constant *C = GetAddrOfConstantString(GetStringForStringLiteral(S)); 1898 if (S->isWide()) { 1899 llvm::Type *DestTy = 1900 llvm::PointerType::getUnqual(getTypes().ConvertType(S->getType())); 1901 C = llvm::ConstantExpr::getBitCast(C, DestTy); 1902 } 1903 return C; 1904} 1905 1906/// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 1907/// array for the given ObjCEncodeExpr node. 1908llvm::Constant * 1909CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 1910 std::string Str; 1911 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 1912 1913 return GetAddrOfConstantCString(Str); 1914} 1915 1916 1917/// GenerateWritableString -- Creates storage for a string literal. 1918static llvm::Constant *GenerateStringLiteral(llvm::StringRef str, 1919 bool constant, 1920 CodeGenModule &CGM, 1921 const char *GlobalName) { 1922 // Create Constant for this string literal. Don't add a '\0'. 1923 llvm::Constant *C = 1924 llvm::ConstantArray::get(CGM.getLLVMContext(), str, false); 1925 1926 // Create a global variable for this string 1927 llvm::GlobalVariable *GV = 1928 new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant, 1929 llvm::GlobalValue::PrivateLinkage, 1930 C, GlobalName); 1931 GV->setAlignment(1); 1932 GV->setUnnamedAddr(true); 1933 return GV; 1934} 1935 1936/// GetAddrOfConstantString - Returns a pointer to a character array 1937/// containing the literal. This contents are exactly that of the 1938/// given string, i.e. it will not be null terminated automatically; 1939/// see GetAddrOfConstantCString. Note that whether the result is 1940/// actually a pointer to an LLVM constant depends on 1941/// Feature.WriteableStrings. 1942/// 1943/// The result has pointer to array type. 1944llvm::Constant *CodeGenModule::GetAddrOfConstantString(llvm::StringRef Str, 1945 const char *GlobalName) { 1946 bool IsConstant = !Features.WritableStrings; 1947 1948 // Get the default prefix if a name wasn't specified. 1949 if (!GlobalName) 1950 GlobalName = ".str"; 1951 1952 // Don't share any string literals if strings aren't constant. 1953 if (!IsConstant) 1954 return GenerateStringLiteral(Str, false, *this, GlobalName); 1955 1956 llvm::StringMapEntry<llvm::Constant *> &Entry = 1957 ConstantStringMap.GetOrCreateValue(Str); 1958 1959 if (Entry.getValue()) 1960 return Entry.getValue(); 1961 1962 // Create a global variable for this. 1963 llvm::Constant *C = GenerateStringLiteral(Str, true, *this, GlobalName); 1964 Entry.setValue(C); 1965 return C; 1966} 1967 1968/// GetAddrOfConstantCString - Returns a pointer to a character 1969/// array containing the literal and a terminating '\0' 1970/// character. The result has pointer to array type. 1971llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &Str, 1972 const char *GlobalName){ 1973 llvm::StringRef StrWithNull(Str.c_str(), Str.size() + 1); 1974 return GetAddrOfConstantString(StrWithNull, GlobalName); 1975} 1976 1977/// EmitObjCPropertyImplementations - Emit information for synthesized 1978/// properties for an implementation. 1979void CodeGenModule::EmitObjCPropertyImplementations(const 1980 ObjCImplementationDecl *D) { 1981 for (ObjCImplementationDecl::propimpl_iterator 1982 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) { 1983 ObjCPropertyImplDecl *PID = *i; 1984 1985 // Dynamic is just for type-checking. 1986 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 1987 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 1988 1989 // Determine which methods need to be implemented, some may have 1990 // been overridden. Note that ::isSynthesized is not the method 1991 // we want, that just indicates if the decl came from a 1992 // property. What we want to know is if the method is defined in 1993 // this implementation. 1994 if (!D->getInstanceMethod(PD->getGetterName())) 1995 CodeGenFunction(*this).GenerateObjCGetter( 1996 const_cast<ObjCImplementationDecl *>(D), PID); 1997 if (!PD->isReadOnly() && 1998 !D->getInstanceMethod(PD->getSetterName())) 1999 CodeGenFunction(*this).GenerateObjCSetter( 2000 const_cast<ObjCImplementationDecl *>(D), PID); 2001 } 2002 } 2003} 2004 2005static bool needsDestructMethod(ObjCImplementationDecl *impl) { 2006 ObjCInterfaceDecl *iface 2007 = const_cast<ObjCInterfaceDecl*>(impl->getClassInterface()); 2008 for (ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 2009 ivar; ivar = ivar->getNextIvar()) 2010 if (ivar->getType().isDestructedType()) 2011 return true; 2012 2013 return false; 2014} 2015 2016/// EmitObjCIvarInitializations - Emit information for ivar initialization 2017/// for an implementation. 2018void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) { 2019 // We might need a .cxx_destruct even if we don't have any ivar initializers. 2020 if (needsDestructMethod(D)) { 2021 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct"); 2022 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 2023 ObjCMethodDecl *DTORMethod = 2024 ObjCMethodDecl::Create(getContext(), D->getLocation(), D->getLocation(), 2025 cxxSelector, getContext().VoidTy, 0, D, true, 2026 false, true, false, ObjCMethodDecl::Required); 2027 D->addInstanceMethod(DTORMethod); 2028 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false); 2029 D->setHasCXXStructors(true); 2030 } 2031 2032 // If the implementation doesn't have any ivar initializers, we don't need 2033 // a .cxx_construct. 2034 if (D->getNumIvarInitializers() == 0) 2035 return; 2036 2037 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct"); 2038 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 2039 // The constructor returns 'self'. 2040 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(), 2041 D->getLocation(), 2042 D->getLocation(), cxxSelector, 2043 getContext().getObjCIdType(), 0, 2044 D, true, false, true, false, 2045 ObjCMethodDecl::Required); 2046 D->addInstanceMethod(CTORMethod); 2047 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true); 2048 D->setHasCXXStructors(true); 2049} 2050 2051/// EmitNamespace - Emit all declarations in a namespace. 2052void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) { 2053 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end(); 2054 I != E; ++I) 2055 EmitTopLevelDecl(*I); 2056} 2057 2058// EmitLinkageSpec - Emit all declarations in a linkage spec. 2059void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 2060 if (LSD->getLanguage() != LinkageSpecDecl::lang_c && 2061 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) { 2062 ErrorUnsupported(LSD, "linkage spec"); 2063 return; 2064 } 2065 2066 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end(); 2067 I != E; ++I) 2068 EmitTopLevelDecl(*I); 2069} 2070 2071/// EmitTopLevelDecl - Emit code for a single top level declaration. 2072void CodeGenModule::EmitTopLevelDecl(Decl *D) { 2073 // If an error has occurred, stop code generation, but continue 2074 // parsing and semantic analysis (to ensure all warnings and errors 2075 // are emitted). 2076 if (Diags.hasErrorOccurred()) 2077 return; 2078 2079 // Ignore dependent declarations. 2080 if (D->getDeclContext() && D->getDeclContext()->isDependentContext()) 2081 return; 2082 2083 switch (D->getKind()) { 2084 case Decl::CXXConversion: 2085 case Decl::CXXMethod: 2086 case Decl::Function: 2087 // Skip function templates 2088 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() || 2089 cast<FunctionDecl>(D)->isLateTemplateParsed()) 2090 return; 2091 2092 EmitGlobal(cast<FunctionDecl>(D)); 2093 break; 2094 2095 case Decl::Var: 2096 EmitGlobal(cast<VarDecl>(D)); 2097 break; 2098 2099 // Indirect fields from global anonymous structs and unions can be 2100 // ignored; only the actual variable requires IR gen support. 2101 case Decl::IndirectField: 2102 break; 2103 2104 // C++ Decls 2105 case Decl::Namespace: 2106 EmitNamespace(cast<NamespaceDecl>(D)); 2107 break; 2108 // No code generation needed. 2109 case Decl::UsingShadow: 2110 case Decl::Using: 2111 case Decl::UsingDirective: 2112 case Decl::ClassTemplate: 2113 case Decl::FunctionTemplate: 2114 case Decl::TypeAliasTemplate: 2115 case Decl::NamespaceAlias: 2116 case Decl::Block: 2117 break; 2118 case Decl::CXXConstructor: 2119 // Skip function templates 2120 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() || 2121 cast<FunctionDecl>(D)->isLateTemplateParsed()) 2122 return; 2123 2124 EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 2125 break; 2126 case Decl::CXXDestructor: 2127 if (cast<FunctionDecl>(D)->isLateTemplateParsed()) 2128 return; 2129 EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 2130 break; 2131 2132 case Decl::StaticAssert: 2133 // Nothing to do. 2134 break; 2135 2136 // Objective-C Decls 2137 2138 // Forward declarations, no (immediate) code generation. 2139 case Decl::ObjCClass: 2140 case Decl::ObjCForwardProtocol: 2141 case Decl::ObjCInterface: 2142 break; 2143 2144 case Decl::ObjCCategory: { 2145 ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D); 2146 if (CD->IsClassExtension() && CD->hasSynthBitfield()) 2147 Context.ResetObjCLayout(CD->getClassInterface()); 2148 break; 2149 } 2150 2151 case Decl::ObjCProtocol: 2152 Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D)); 2153 break; 2154 2155 case Decl::ObjCCategoryImpl: 2156 // Categories have properties but don't support synthesize so we 2157 // can ignore them here. 2158 Runtime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 2159 break; 2160 2161 case Decl::ObjCImplementation: { 2162 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D); 2163 if (Features.ObjCNonFragileABI2 && OMD->hasSynthBitfield()) 2164 Context.ResetObjCLayout(OMD->getClassInterface()); 2165 EmitObjCPropertyImplementations(OMD); 2166 EmitObjCIvarInitializations(OMD); 2167 Runtime->GenerateClass(OMD); 2168 break; 2169 } 2170 case Decl::ObjCMethod: { 2171 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D); 2172 // If this is not a prototype, emit the body. 2173 if (OMD->getBody()) 2174 CodeGenFunction(*this).GenerateObjCMethod(OMD); 2175 break; 2176 } 2177 case Decl::ObjCCompatibleAlias: 2178 // compatibility-alias is a directive and has no code gen. 2179 break; 2180 2181 case Decl::LinkageSpec: 2182 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 2183 break; 2184 2185 case Decl::FileScopeAsm: { 2186 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D); 2187 llvm::StringRef AsmString = AD->getAsmString()->getString(); 2188 2189 const std::string &S = getModule().getModuleInlineAsm(); 2190 if (S.empty()) 2191 getModule().setModuleInlineAsm(AsmString); 2192 else 2193 getModule().setModuleInlineAsm(S + '\n' + AsmString.str()); 2194 break; 2195 } 2196 2197 default: 2198 // Make sure we handled everything we should, every other kind is a 2199 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 2200 // function. Need to recode Decl::Kind to do that easily. 2201 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 2202 } 2203} 2204 2205/// Turns the given pointer into a constant. 2206static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context, 2207 const void *Ptr) { 2208 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr); 2209 const llvm::Type *i64 = llvm::Type::getInt64Ty(Context); 2210 return llvm::ConstantInt::get(i64, PtrInt); 2211} 2212 2213static void EmitGlobalDeclMetadata(CodeGenModule &CGM, 2214 llvm::NamedMDNode *&GlobalMetadata, 2215 GlobalDecl D, 2216 llvm::GlobalValue *Addr) { 2217 if (!GlobalMetadata) 2218 GlobalMetadata = 2219 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs"); 2220 2221 // TODO: should we report variant information for ctors/dtors? 2222 llvm::Value *Ops[] = { 2223 Addr, 2224 GetPointerConstant(CGM.getLLVMContext(), D.getDecl()) 2225 }; 2226 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 2227} 2228 2229/// Emits metadata nodes associating all the global values in the 2230/// current module with the Decls they came from. This is useful for 2231/// projects using IR gen as a subroutine. 2232/// 2233/// Since there's currently no way to associate an MDNode directly 2234/// with an llvm::GlobalValue, we create a global named metadata 2235/// with the name 'clang.global.decl.ptrs'. 2236void CodeGenModule::EmitDeclMetadata() { 2237 llvm::NamedMDNode *GlobalMetadata = 0; 2238 2239 // StaticLocalDeclMap 2240 for (llvm::DenseMap<GlobalDecl,llvm::StringRef>::iterator 2241 I = MangledDeclNames.begin(), E = MangledDeclNames.end(); 2242 I != E; ++I) { 2243 llvm::GlobalValue *Addr = getModule().getNamedValue(I->second); 2244 EmitGlobalDeclMetadata(*this, GlobalMetadata, I->first, Addr); 2245 } 2246} 2247 2248/// Emits metadata nodes for all the local variables in the current 2249/// function. 2250void CodeGenFunction::EmitDeclMetadata() { 2251 if (LocalDeclMap.empty()) return; 2252 2253 llvm::LLVMContext &Context = getLLVMContext(); 2254 2255 // Find the unique metadata ID for this name. 2256 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr"); 2257 2258 llvm::NamedMDNode *GlobalMetadata = 0; 2259 2260 for (llvm::DenseMap<const Decl*, llvm::Value*>::iterator 2261 I = LocalDeclMap.begin(), E = LocalDeclMap.end(); I != E; ++I) { 2262 const Decl *D = I->first; 2263 llvm::Value *Addr = I->second; 2264 2265 if (llvm::AllocaInst *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) { 2266 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D); 2267 Alloca->setMetadata(DeclPtrKind, llvm::MDNode::get(Context, DAddr)); 2268 } else if (llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>(Addr)) { 2269 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D)); 2270 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV); 2271 } 2272 } 2273} 2274 2275void CodeGenModule::EmitCoverageFile() { 2276 if (!getCodeGenOpts().CoverageFile.empty()) { 2277 if (llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu")) { 2278 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov"); 2279 llvm::LLVMContext &Ctx = TheModule.getContext(); 2280 llvm::MDString *CoverageFile = 2281 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageFile); 2282 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) { 2283 llvm::MDNode *CU = CUNode->getOperand(i); 2284 llvm::Value *node[] = { CoverageFile, CU }; 2285 llvm::MDNode *N = llvm::MDNode::get(Ctx, node); 2286 GCov->addOperand(N); 2287 } 2288 } 2289 } 2290} 2291 2292///@name Custom Runtime Function Interfaces 2293///@{ 2294// 2295// FIXME: These can be eliminated once we can have clients just get the required 2296// AST nodes from the builtin tables. 2297 2298llvm::Constant *CodeGenModule::getBlockObjectDispose() { 2299 if (BlockObjectDispose) 2300 return BlockObjectDispose; 2301 2302 // If we saw an explicit decl, use that. 2303 if (BlockObjectDisposeDecl) { 2304 return BlockObjectDispose = GetAddrOfFunction( 2305 BlockObjectDisposeDecl, 2306 getTypes().GetFunctionType(BlockObjectDisposeDecl)); 2307 } 2308 2309 // Otherwise construct the function by hand. 2310 const llvm::Type *args[] = { Int8PtrTy, Int32Ty }; 2311 const llvm::FunctionType *fty 2312 = llvm::FunctionType::get(VoidTy, args, false); 2313 return BlockObjectDispose = 2314 CreateRuntimeFunction(fty, "_Block_object_dispose"); 2315} 2316 2317llvm::Constant *CodeGenModule::getBlockObjectAssign() { 2318 if (BlockObjectAssign) 2319 return BlockObjectAssign; 2320 2321 // If we saw an explicit decl, use that. 2322 if (BlockObjectAssignDecl) { 2323 return BlockObjectAssign = GetAddrOfFunction( 2324 BlockObjectAssignDecl, 2325 getTypes().GetFunctionType(BlockObjectAssignDecl)); 2326 } 2327 2328 // Otherwise construct the function by hand. 2329 const llvm::Type *args[] = { Int8PtrTy, Int8PtrTy, Int32Ty }; 2330 const llvm::FunctionType *fty 2331 = llvm::FunctionType::get(VoidTy, args, false); 2332 return BlockObjectAssign = 2333 CreateRuntimeFunction(fty, "_Block_object_assign"); 2334} 2335 2336llvm::Constant *CodeGenModule::getNSConcreteGlobalBlock() { 2337 if (NSConcreteGlobalBlock) 2338 return NSConcreteGlobalBlock; 2339 2340 // If we saw an explicit decl, use that. 2341 if (NSConcreteGlobalBlockDecl) { 2342 return NSConcreteGlobalBlock = GetAddrOfGlobalVar( 2343 NSConcreteGlobalBlockDecl, 2344 getTypes().ConvertType(NSConcreteGlobalBlockDecl->getType())); 2345 } 2346 2347 // Otherwise construct the variable by hand. 2348 return NSConcreteGlobalBlock = 2349 CreateRuntimeVariable(Int8PtrTy, "_NSConcreteGlobalBlock"); 2350} 2351 2352llvm::Constant *CodeGenModule::getNSConcreteStackBlock() { 2353 if (NSConcreteStackBlock) 2354 return NSConcreteStackBlock; 2355 2356 // If we saw an explicit decl, use that. 2357 if (NSConcreteStackBlockDecl) { 2358 return NSConcreteStackBlock = GetAddrOfGlobalVar( 2359 NSConcreteStackBlockDecl, 2360 getTypes().ConvertType(NSConcreteStackBlockDecl->getType())); 2361 } 2362 2363 // Otherwise construct the variable by hand. 2364 return NSConcreteStackBlock = 2365 CreateRuntimeVariable(Int8PtrTy, "_NSConcreteStackBlock"); 2366} 2367 2368///@} 2369