1 //===--- CGDebugInfo.h - DebugInfo for LLVM CodeGen -------------*- C++ -*-===// 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 is the source-level debug info generator for llvm translation. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H 15 #define LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H 16 17 #include "CGBuilder.h" 18 #include "clang/AST/Expr.h" 19 #include "clang/AST/Type.h" 20 #include "clang/Basic/SourceLocation.h" 21 #include "clang/Frontend/CodeGenOptions.h" 22 #include "llvm/ADT/DenseMap.h" 23 #include "llvm/IR/DIBuilder.h" 24 #include "llvm/IR/DebugInfo.h" 25 #include "llvm/IR/ValueHandle.h" 26 #include "llvm/Support/Allocator.h" 27 28 namespace llvm { 29 class MDNode; 30 } 31 32 namespace clang { 33 class CXXMethodDecl; 34 class VarDecl; 35 class ObjCInterfaceDecl; 36 class ObjCIvarDecl; 37 class ClassTemplateSpecializationDecl; 38 class GlobalDecl; 39 class UsingDecl; 40 41 namespace CodeGen { 42 class CodeGenModule; 43 class CodeGenFunction; 44 class CGBlockInfo; 45 46 /// This class gathers all debug information during compilation and is 47 /// responsible for emitting to llvm globals or pass directly to the 48 /// backend. 49 class CGDebugInfo { 50 friend class ApplyDebugLocation; 51 friend class SaveAndRestoreLocation; 52 CodeGenModule &CGM; 53 const CodeGenOptions::DebugInfoKind DebugKind; 54 llvm::DIBuilder DBuilder; 55 llvm::DICompileUnit *TheCU = nullptr; 56 SourceLocation CurLoc; 57 llvm::DIType *VTablePtrType = nullptr; 58 llvm::DIType *ClassTy = nullptr; 59 llvm::DICompositeType *ObjTy = nullptr; 60 llvm::DIType *SelTy = nullptr; 61 llvm::DIType *OCLImage1dDITy = nullptr; 62 llvm::DIType *OCLImage1dArrayDITy = nullptr; 63 llvm::DIType *OCLImage1dBufferDITy = nullptr; 64 llvm::DIType *OCLImage2dDITy = nullptr; 65 llvm::DIType *OCLImage2dArrayDITy = nullptr; 66 llvm::DIType *OCLImage3dDITy = nullptr; 67 llvm::DIType *OCLEventDITy = nullptr; 68 69 /// Cache of previously constructed Types. 70 llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache; 71 72 struct ObjCInterfaceCacheEntry { 73 const ObjCInterfaceType *Type; 74 llvm::DIType *Decl; 75 llvm::DIFile *Unit; ObjCInterfaceCacheEntryObjCInterfaceCacheEntry76 ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl, 77 llvm::DIFile *Unit) 78 : Type(Type), Decl(Decl), Unit(Unit) {} 79 }; 80 81 /// Cache of previously constructed interfaces which may change. 82 llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache; 83 84 /// Cache of references to AST files such as PCHs or modules. 85 llvm::DenseMap<uint64_t, llvm::DIModule *> ModuleRefCache; 86 87 /// List of interfaces we want to keep even if orphaned. 88 std::vector<void *> RetainedTypes; 89 90 /// Cache of forward declared types to RAUW at the end of 91 /// compilation. 92 std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap; 93 94 /// Cache of replaceable forward declarartions (functions and 95 /// variables) to RAUW at the end of compilation. 96 std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>> 97 FwdDeclReplaceMap; 98 99 /// Keep track of our current nested lexical block. 100 std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack; 101 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap; 102 /// Keep track of LexicalBlockStack counter at the beginning of a 103 /// function. This is used to pop unbalanced regions at the end of a 104 /// function. 105 std::vector<unsigned> FnBeginRegionCount; 106 107 /// This is a storage for names that are constructed on demand. For 108 /// example, C++ destructors, C++ operators etc.. 109 llvm::BumpPtrAllocator DebugInfoNames; 110 StringRef CWDName; 111 112 llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache; 113 llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache; 114 /// Cache declarations relevant to DW_TAG_imported_declarations (C++ 115 /// using declarations) that aren't covered by other more specific caches. 116 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache; 117 llvm::DenseMap<const NamespaceDecl *, llvm::TrackingMDRef> NameSpaceCache; 118 llvm::DenseMap<const NamespaceAliasDecl *, llvm::TrackingMDRef> 119 NamespaceAliasCache; 120 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> StaticDataMemberCache; 121 122 /// Helper functions for getOrCreateType. 123 /// @{ 124 /// Currently the checksum of an interface includes the number of 125 /// ivars and property accessors. 126 unsigned Checksum(const ObjCInterfaceDecl *InterfaceDecl); 127 llvm::DIType *CreateType(const BuiltinType *Ty); 128 llvm::DIType *CreateType(const ComplexType *Ty); 129 llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg); 130 llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg); 131 llvm::DIType *CreateType(const TemplateSpecializationType *Ty, 132 llvm::DIFile *Fg); 133 llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F); 134 llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F); 135 llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F); 136 llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F); 137 /// Get structure or union type. 138 llvm::DIType *CreateType(const RecordType *Tyg); 139 llvm::DIType *CreateTypeDefinition(const RecordType *Ty); 140 llvm::DICompositeType *CreateLimitedType(const RecordType *Ty); 141 void CollectContainingType(const CXXRecordDecl *RD, 142 llvm::DICompositeType *CT); 143 /// Get Objective-C interface type. 144 llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F); 145 llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty, 146 llvm::DIFile *F); 147 /// Get Objective-C object type. 148 llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F); 149 llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F); 150 llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F); 151 llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F); 152 llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit); 153 llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F); 154 llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F); 155 /// Get enumeration type. 156 llvm::DIType *CreateEnumType(const EnumType *Ty); 157 llvm::DIType *CreateTypeDefinition(const EnumType *Ty); 158 /// Look up the completed type for a self pointer in the TypeCache and 159 /// create a copy of it with the ObjectPointer and Artificial flags 160 /// set. If the type is not cached, a new one is created. This should 161 /// never happen though, since creating a type for the implicit self 162 /// argument implies that we already parsed the interface definition 163 /// and the ivar declarations in the implementation. 164 llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty); 165 /// @} 166 167 /// Get the type from the cache or return null type if it doesn't 168 /// exist. 169 llvm::DIType *getTypeOrNull(const QualType); 170 /// Return the debug type for a C++ method. 171 /// \arg CXXMethodDecl is of FunctionType. This function type is 172 /// not updated to include implicit \c this pointer. Use this routine 173 /// to get a method type which includes \c this pointer. 174 llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method, 175 llvm::DIFile *F); 176 llvm::DISubroutineType * 177 getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func, 178 llvm::DIFile *Unit); 179 llvm::DISubroutineType * 180 getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F); 181 /// \return debug info descriptor for vtable. 182 llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F); 183 /// \return namespace descriptor for the given namespace decl. 184 llvm::DINamespace *getOrCreateNameSpace(const NamespaceDecl *N); 185 llvm::DIType *getOrCreateTypeDeclaration(QualType PointeeTy, llvm::DIFile *F); 186 llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty, 187 QualType PointeeTy, llvm::DIFile *F); 188 189 llvm::Value *getCachedInterfaceTypeOrNull(const QualType Ty); 190 llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache); 191 192 /// A helper function to create a subprogram for a single member 193 /// function GlobalDecl. 194 llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method, 195 llvm::DIFile *F, 196 llvm::DIType *RecordTy); 197 198 /// A helper function to collect debug info for C++ member 199 /// functions. This is used while creating debug info entry for a 200 /// Record. 201 void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F, 202 SmallVectorImpl<llvm::Metadata *> &E, 203 llvm::DIType *T); 204 205 /// A helper function to collect debug info for C++ base 206 /// classes. This is used while creating debug info entry for a 207 /// Record. 208 void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F, 209 SmallVectorImpl<llvm::Metadata *> &EltTys, 210 llvm::DIType *RecordTy); 211 212 /// A helper function to collect template parameters. 213 llvm::DINodeArray CollectTemplateParams(const TemplateParameterList *TPList, 214 ArrayRef<TemplateArgument> TAList, 215 llvm::DIFile *Unit); 216 /// A helper function to collect debug info for function template 217 /// parameters. 218 llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD, 219 llvm::DIFile *Unit); 220 221 /// A helper function to collect debug info for template 222 /// parameters. 223 llvm::DINodeArray 224 CollectCXXTemplateParams(const ClassTemplateSpecializationDecl *TS, 225 llvm::DIFile *F); 226 227 llvm::DIType *createFieldType(StringRef name, QualType type, 228 uint64_t sizeInBitsOverride, SourceLocation loc, 229 AccessSpecifier AS, uint64_t offsetInBits, 230 llvm::DIFile *tunit, llvm::DIScope *scope, 231 const RecordDecl *RD = nullptr); 232 233 /// Helpers for collecting fields of a record. 234 /// @{ 235 void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl, 236 SmallVectorImpl<llvm::Metadata *> &E, 237 llvm::DIType *RecordTy); 238 llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var, 239 llvm::DIType *RecordTy, 240 const RecordDecl *RD); 241 void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits, 242 llvm::DIFile *F, 243 SmallVectorImpl<llvm::Metadata *> &E, 244 llvm::DIType *RecordTy, const RecordDecl *RD); 245 void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F, 246 SmallVectorImpl<llvm::Metadata *> &E, 247 llvm::DICompositeType *RecordTy); 248 249 /// If the C++ class has vtable info then insert appropriate debug 250 /// info entry in EltTys vector. 251 void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F, 252 SmallVectorImpl<llvm::Metadata *> &EltTys); 253 /// @} 254 255 /// Create a new lexical block node and push it on the stack. 256 void CreateLexicalBlock(SourceLocation Loc); 257 258 public: 259 CGDebugInfo(CodeGenModule &CGM); 260 ~CGDebugInfo(); 261 262 void finalize(); 263 264 /// Update the current source location. If \arg loc is invalid it is 265 /// ignored. 266 void setLocation(SourceLocation Loc); 267 268 /// Emit metadata to indicate a change in line/column information in 269 /// the source file. If the location is invalid, the previous 270 /// location will be reused. 271 void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc); 272 273 /// Emit a call to llvm.dbg.function.start to indicate 274 /// start of a new function. 275 /// \param Loc The location of the function header. 276 /// \param ScopeLoc The location of the function body. 277 void EmitFunctionStart(GlobalDecl GD, SourceLocation Loc, 278 SourceLocation ScopeLoc, QualType FnType, 279 llvm::Function *Fn, CGBuilderTy &Builder); 280 281 /// Constructs the debug code for exiting a function. 282 void EmitFunctionEnd(CGBuilderTy &Builder); 283 284 /// Emit metadata to indicate the beginning of a new lexical block 285 /// and push the block onto the stack. 286 void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc); 287 288 /// Emit metadata to indicate the end of a new lexical block and pop 289 /// the current block. 290 void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc); 291 292 /// Emit call to \c llvm.dbg.declare for an automatic variable 293 /// declaration. 294 void EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI, 295 CGBuilderTy &Builder); 296 297 /// Emit call to \c llvm.dbg.declare for an imported variable 298 /// declaration in a block. 299 void EmitDeclareOfBlockDeclRefVariable(const VarDecl *variable, 300 llvm::Value *storage, 301 CGBuilderTy &Builder, 302 const CGBlockInfo &blockInfo, 303 llvm::Instruction *InsertPoint = 0); 304 305 /// Emit call to \c llvm.dbg.declare for an argument variable 306 /// declaration. 307 void EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI, 308 unsigned ArgNo, CGBuilderTy &Builder); 309 310 /// Emit call to \c llvm.dbg.declare for the block-literal argument 311 /// to a block invocation function. 312 void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block, 313 llvm::Value *Arg, unsigned ArgNo, 314 llvm::Value *LocalAddr, 315 CGBuilderTy &Builder); 316 317 /// Emit information about a global variable. 318 void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl); 319 320 /// Emit global variable's debug info. 321 void EmitGlobalVariable(const ValueDecl *VD, llvm::Constant *Init); 322 323 /// Emit C++ using directive. 324 void EmitUsingDirective(const UsingDirectiveDecl &UD); 325 326 /// Emit the type explicitly casted to. 327 void EmitExplicitCastType(QualType Ty); 328 329 /// Emit C++ using declaration. 330 void EmitUsingDecl(const UsingDecl &UD); 331 332 /// Emit an @import declaration. 333 void EmitImportDecl(const ImportDecl &ID); 334 335 /// Emit C++ namespace alias. 336 llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA); 337 338 /// Emit record type's standalone debug info. 339 llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L); 340 341 /// Emit an Objective-C interface type standalone debug info. 342 llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc); 343 344 void completeType(const EnumDecl *ED); 345 void completeType(const RecordDecl *RD); 346 void completeRequiredType(const RecordDecl *RD); 347 void completeClassData(const RecordDecl *RD); 348 349 void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD); 350 351 private: 352 /// Emit call to llvm.dbg.declare for a variable declaration. 353 /// Tag accepts custom types DW_TAG_arg_variable and DW_TAG_auto_variable, 354 /// otherwise would be of type llvm::dwarf::Tag. 355 void EmitDeclare(const VarDecl *decl, llvm::dwarf::Tag Tag, llvm::Value *AI, 356 unsigned ArgNo, CGBuilderTy &Builder); 357 358 /// Build up structure info for the byref. See \a BuildByRefType. 359 llvm::DIType *EmitTypeForVarWithBlocksAttr(const VarDecl *VD, 360 uint64_t *OffSet); 361 362 /// Get context info for the decl. 363 llvm::DIScope *getContextDescriptor(const Decl *Decl); 364 365 llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl); 366 367 /// Create a forward decl for a RecordType in a given context. 368 llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *, 369 llvm::DIScope *); 370 371 /// Return current directory name. 372 StringRef getCurrentDirname(); 373 374 /// Create new compile unit. 375 void CreateCompileUnit(); 376 377 /// Get the file debug info descriptor for the input location. 378 llvm::DIFile *getOrCreateFile(SourceLocation Loc); 379 380 /// Get the file info for main compile unit. 381 llvm::DIFile *getOrCreateMainFile(); 382 383 /// Get the type from the cache or create a new type if necessary. 384 llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg); 385 386 /// Get a reference to a clang module. 387 llvm::DIModule * 388 getOrCreateModuleRef(ExternalASTSource::ASTSourceDescriptor Mod); 389 390 /// Get the type from the cache or create a new partial type if 391 /// necessary. 392 llvm::DIType *getOrCreateLimitedType(const RecordType *Ty, llvm::DIFile *F); 393 394 /// Create type metadata for a source language type. 395 llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg); 396 397 /// Return the underlying ObjCInterfaceDecl if \arg Ty is an 398 /// ObjCInterface or a pointer to one. 399 ObjCInterfaceDecl *getObjCInterfaceDecl(QualType Ty); 400 401 /// Create new member and increase Offset by FType's size. 402 llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType, 403 StringRef Name, uint64_t *Offset); 404 405 /// Retrieve the DIDescriptor, if any, for the canonical form of this 406 /// declaration. 407 llvm::DINode *getDeclarationOrDefinition(const Decl *D); 408 409 /// \return debug info descriptor to describe method 410 /// declaration for the given method definition. 411 llvm::DISubprogram *getFunctionDeclaration(const Decl *D); 412 413 /// \return debug info descriptor to describe in-class static data 414 /// member declaration for the given out-of-class definition. If D 415 /// is an out-of-class definition of a static data member of a 416 /// class, find its corresponding in-class declaration. 417 llvm::DIDerivedType * 418 getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D); 419 420 /// Create a subprogram describing the forward declaration 421 /// represented in the given FunctionDecl. 422 llvm::DISubprogram *getFunctionForwardDeclaration(const FunctionDecl *FD); 423 424 /// Create a global variable describing the forward decalration 425 /// represented in the given VarDecl. 426 llvm::DIGlobalVariable * 427 getGlobalVariableForwardDeclaration(const VarDecl *VD); 428 429 /// \brief Return a global variable that represents one of the 430 /// collection of global variables created for an anonmyous union. 431 /// 432 /// Recursively collect all of the member fields of a global 433 /// anonymous decl and create static variables for them. The first 434 /// time this is called it needs to be on a union and then from 435 /// there we can have additional unnamed fields. 436 llvm::DIGlobalVariable * 437 CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit, 438 unsigned LineNo, StringRef LinkageName, 439 llvm::GlobalVariable *Var, llvm::DIScope *DContext); 440 441 /// Get function name for the given FunctionDecl. If the name is 442 /// constructed on demand (e.g., C++ destructor) then the name is 443 /// stored on the side. 444 StringRef getFunctionName(const FunctionDecl *FD); 445 446 /// Returns the unmangled name of an Objective-C method. 447 /// This is the display name for the debugging info. 448 StringRef getObjCMethodName(const ObjCMethodDecl *FD); 449 450 /// Return selector name. This is used for debugging 451 /// info. 452 StringRef getSelectorName(Selector S); 453 454 /// Get class name including template argument list. 455 StringRef getClassName(const RecordDecl *RD); 456 457 /// Get the vtable name for the given class. 458 StringRef getVTableName(const CXXRecordDecl *Decl); 459 460 /// Get line number for the location. If location is invalid 461 /// then use current location. 462 unsigned getLineNumber(SourceLocation Loc); 463 464 /// Get column number for the location. If location is 465 /// invalid then use current location. 466 /// \param Force Assume DebugColumnInfo option is true. 467 unsigned getColumnNumber(SourceLocation Loc, bool Force = false); 468 469 /// Collect various properties of a FunctionDecl. 470 /// \param GD A GlobalDecl whose getDecl() must return a FunctionDecl. 471 void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit, 472 StringRef &Name, StringRef &LinkageName, 473 llvm::DIScope *&FDContext, 474 llvm::DINodeArray &TParamsArray, 475 unsigned &Flags); 476 477 /// Collect various properties of a VarDecl. 478 void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit, 479 unsigned &LineNo, QualType &T, StringRef &Name, 480 StringRef &LinkageName, llvm::DIScope *&VDContext); 481 482 /// Allocate a copy of \p A using the DebugInfoNames allocator 483 /// and return a reference to it. If multiple arguments are given the strings 484 /// are concatenated. 485 StringRef internString(StringRef A, StringRef B = StringRef()) { 486 char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size()); 487 if (!A.empty()) 488 std::memcpy(Data, A.data(), A.size()); 489 if (!B.empty()) 490 std::memcpy(Data + A.size(), B.data(), B.size()); 491 return StringRef(Data, A.size() + B.size()); 492 } 493 }; 494 495 /// A scoped helper to set the current debug location to the specified 496 /// location or preferred location of the specified Expr. 497 class ApplyDebugLocation { 498 private: 499 void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false); 500 ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty, 501 SourceLocation TemporaryLocation); 502 503 llvm::DebugLoc OriginalLocation; 504 CodeGenFunction &CGF; 505 506 public: 507 /// Set the location to the (valid) TemporaryLocation. 508 ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation); 509 ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E); 510 ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc); 511 512 ~ApplyDebugLocation(); 513 514 /// \brief Apply TemporaryLocation if it is valid. Otherwise switch 515 /// to an artificial debug location that has a valid scope, but no 516 /// line information. 517 /// 518 /// Artificial locations are useful when emitting compiler-generated 519 /// helper functions that have no source location associated with 520 /// them. The DWARF specification allows the compiler to use the 521 /// special line number 0 to indicate code that can not be 522 /// attributed to any source location. Note that passing an empty 523 /// SourceLocation to CGDebugInfo::setLocation() will result in the 524 /// last valid location being reused. CreateArtificial(CodeGenFunction & CGF)525 static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) { 526 return ApplyDebugLocation(CGF, false, SourceLocation()); 527 } 528 /// \brief Apply TemporaryLocation if it is valid. Otherwise switch 529 /// to an artificial debug location that has a valid scope, but no 530 /// line information. 531 static ApplyDebugLocation CreateDefaultArtificial(CodeGenFunction & CGF,SourceLocation TemporaryLocation)532 CreateDefaultArtificial(CodeGenFunction &CGF, 533 SourceLocation TemporaryLocation) { 534 return ApplyDebugLocation(CGF, false, TemporaryLocation); 535 } 536 537 /// Set the IRBuilder to not attach debug locations. Note that 538 /// passing an empty SourceLocation to \a CGDebugInfo::setLocation() 539 /// will result in the last valid location being reused. Note that 540 /// all instructions that do not have a location at the beginning of 541 /// a function are counted towards to funciton prologue. CreateEmpty(CodeGenFunction & CGF)542 static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) { 543 return ApplyDebugLocation(CGF, true, SourceLocation()); 544 } 545 546 /// \brief Apply TemporaryLocation if it is valid. Otherwise set the IRBuilder 547 /// to not attach debug locations. 548 static ApplyDebugLocation CreateDefaultEmpty(CodeGenFunction & CGF,SourceLocation TemporaryLocation)549 CreateDefaultEmpty(CodeGenFunction &CGF, SourceLocation TemporaryLocation) { 550 return ApplyDebugLocation(CGF, true, TemporaryLocation); 551 } 552 }; 553 554 } // namespace CodeGen 555 } // namespace clang 556 557 #endif 558