clang/lib/CodeGen/CGDebugInfo.h

   1 //===--- CGDebugInfo.h - DebugInfo for LLVM CodeGen -------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This is the source-level debug info generator for llvm translation.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H
  14 #define LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H
  15
  16 #include "CGBuilder.h"
  17 #include "clang/AST/DeclCXX.h"
  18 #include "clang/AST/Expr.h"
  19 #include "clang/AST/ExternalASTSource.h"
  20 #include "clang/AST/PrettyPrinter.h"
  21 #include "clang/AST/Type.h"
  22 #include "clang/AST/TypeOrdering.h"
  23 #include "clang/Basic/CodeGenOptions.h"
  24 #include "clang/Basic/Module.h"
  25 #include "clang/Basic/SourceLocation.h"
  26 #include "llvm/ADT/DenseMap.h"
  27 #include "llvm/ADT/DenseSet.h"
  28 #include "llvm/IR/DIBuilder.h"
  29 #include "llvm/IR/DebugInfo.h"
  30 #include "llvm/IR/ValueHandle.h"
  31 #include "llvm/Support/Allocator.h"
  32 #include <optional>
  33
  34 namespace llvm {
  35 class MDNode;
  36 }
  37
  38 namespace clang {
  39 class ClassTemplateSpecializationDecl;
  40 class GlobalDecl;
  41 class ModuleMap;
  42 class ObjCInterfaceDecl;
  43 class UsingDecl;
  44 class VarDecl;
  45 enum class DynamicInitKind : unsigned;
  46
  47 namespace CodeGen {
  48 class CodeGenModule;
  49 class CodeGenFunction;
  50 class CGBlockInfo;
  51
  52 /// This class gathers all debug information during compilation and is
  53 /// responsible for emitting to llvm globals or pass directly to the
  54 /// backend.
  55 class CGDebugInfo {
  56   friend class ApplyDebugLocation;
  57   friend class SaveAndRestoreLocation;
  58   CodeGenModule &CGM;
  59   const llvm::codegenoptions::DebugInfoKind DebugKind;
  60   bool DebugTypeExtRefs;
  61   llvm::DIBuilder DBuilder;
  62   llvm::DICompileUnit *TheCU = nullptr;
  63   ModuleMap *ClangModuleMap = nullptr;
  64   ASTSourceDescriptor PCHDescriptor;
  65   SourceLocation CurLoc;
  66   llvm::MDNode *CurInlinedAt = nullptr;
  67   llvm::DIType *VTablePtrType = nullptr;
  68   llvm::DIType *ClassTy = nullptr;
  69   llvm::DICompositeType *ObjTy = nullptr;
  70   llvm::DIType *SelTy = nullptr;
  71 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \
  72   llvm::DIType *SingletonId = nullptr;
  73 #include "clang/Basic/OpenCLImageTypes.def"
  74   llvm::DIType *OCLSamplerDITy = nullptr;
  75   llvm::DIType *OCLEventDITy = nullptr;
  76   llvm::DIType *OCLClkEventDITy = nullptr;
  77   llvm::DIType *OCLQueueDITy = nullptr;
  78   llvm::DIType *OCLNDRangeDITy = nullptr;
  79   llvm::DIType *OCLReserveIDDITy = nullptr;
  80 #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
  81   llvm::DIType *Id##Ty = nullptr;
  82 #include "clang/Basic/OpenCLExtensionTypes.def"
  83 #define WASM_TYPE(Name, Id, SingletonId) llvm::DIType *SingletonId = nullptr;
  84 #include "clang/Basic/WebAssemblyReferenceTypes.def"
  85
  86   /// Cache of previously constructed Types.
  87   llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache;
  88
  89   /// Cache that maps VLA types to size expressions for that type,
  90   /// represented by instantiated Metadata nodes.
  91   llvm::SmallDenseMap<QualType, llvm::Metadata *> SizeExprCache;
  92
  93   /// Callbacks to use when printing names and types.
  94   class PrintingCallbacks final : public clang::PrintingCallbacks {
  95     const CGDebugInfo &Self;
  96
  97   public:
  98     PrintingCallbacks(const CGDebugInfo &Self) : Self(Self) {}
  99     std::string remapPath(StringRef Path) const override {
 100       return Self.remapDIPath(Path);
 101     }
 102   };
 103   PrintingCallbacks PrintCB = {*this};
 104
 105   struct ObjCInterfaceCacheEntry {
 106     const ObjCInterfaceType *Type;
 107     llvm::DIType *Decl;
 108     llvm::DIFile *Unit;
 109     ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl,
 110                             llvm::DIFile *Unit)
 111         : Type(Type), Decl(Decl), Unit(Unit) {}
 112   };
 113
 114   /// Cache of previously constructed interfaces which may change.
 115   llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;
 116
 117   /// Cache of forward declarations for methods belonging to the interface.
 118   /// The extra bit on the DISubprogram specifies whether a method is
 119   /// "objc_direct".
 120   llvm::DenseMap<const ObjCInterfaceDecl *,
 121                  std::vector<llvm::PointerIntPair<llvm::DISubprogram *, 1>>>
 122       ObjCMethodCache;
 123
 124   /// Cache of references to clang modules and precompiled headers.
 125   llvm::DenseMap<const Module *, llvm::TrackingMDRef> ModuleCache;
 126
 127   /// List of interfaces we want to keep even if orphaned.
 128   std::vector<void *> RetainedTypes;
 129
 130   /// Cache of forward declared types to RAUW at the end of compilation.
 131   std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap;
 132
 133   /// Cache of replaceable forward declarations (functions and
 134   /// variables) to RAUW at the end of compilation.
 135   std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>>
 136       FwdDeclReplaceMap;
 137
 138   /// Keep track of our current nested lexical block.
 139   std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;
 140   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;
 141   /// Keep track of LexicalBlockStack counter at the beginning of a
 142   /// function. This is used to pop unbalanced regions at the end of a
 143   /// function.
 144   std::vector<unsigned> FnBeginRegionCount;
 145
 146   /// This is a storage for names that are constructed on demand. For
 147   /// example, C++ destructors, C++ operators etc..
 148   llvm::BumpPtrAllocator DebugInfoNames;
 149   StringRef CWDName;
 150
 151   llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;
 152   llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;
 153   /// Cache declarations relevant to DW_TAG_imported_declarations (C++
 154   /// using declarations and global alias variables) that aren't covered
 155   /// by other more specific caches.
 156   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache;
 157   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> ImportedDeclCache;
 158   llvm::DenseMap<const NamespaceDecl *, llvm::TrackingMDRef> NamespaceCache;
 159   llvm::DenseMap<const NamespaceAliasDecl *, llvm::TrackingMDRef>
 160       NamespaceAliasCache;
 161   llvm::DenseMap<const Decl *, llvm::TypedTrackingMDRef<llvm::DIDerivedType>>
 162       StaticDataMemberCache;
 163
 164   using ParamDecl2StmtTy = llvm::DenseMap<const ParmVarDecl *, const Stmt *>;
 165   using Param2DILocTy =
 166       llvm::DenseMap<const ParmVarDecl *, llvm::DILocalVariable *>;
 167
 168   /// The key is coroutine real parameters, value is coroutine move parameters.
 169   ParamDecl2StmtTy CoroutineParameterMappings;
 170   /// The key is coroutine real parameters, value is DIVariable in LLVM IR.
 171   Param2DILocTy ParamDbgMappings;
 172
 173   /// Helper functions for getOrCreateType.
 174   /// @{
 175   /// Currently the checksum of an interface includes the number of
 176   /// ivars and property accessors.
 177   llvm::DIType *CreateType(const BuiltinType *Ty);
 178   llvm::DIType *CreateType(const ComplexType *Ty);
 179   llvm::DIType *CreateType(const BitIntType *Ty);
 180   llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg);
 181   llvm::DIType *CreateQualifiedType(const FunctionProtoType *Ty,
 182                                     llvm::DIFile *Fg);
 183   llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg);
 184   llvm::DIType *CreateType(const TemplateSpecializationType *Ty,
 185                            llvm::DIFile *Fg);
 186   llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F);
 187   llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F);
 188   llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F);
 189   llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F);
 190   /// Get structure or union type.
 191   llvm::DIType *CreateType(const RecordType *Tyg);
 192
 193   /// Create definition for the specified 'Ty'.
 194   ///
 195   /// \returns A pair of 'llvm::DIType's. The first is the definition
 196   /// of the 'Ty'. The second is the type specified by the preferred_name
 197   /// attribute on 'Ty', which can be a nullptr if no such attribute
 198   /// exists.
 199   std::pair<llvm::DIType *, llvm::DIType *>
 200   CreateTypeDefinition(const RecordType *Ty);
 201   llvm::DICompositeType *CreateLimitedType(const RecordType *Ty);
 202   void CollectContainingType(const CXXRecordDecl *RD,
 203                              llvm::DICompositeType *CT);
 204   /// Get Objective-C interface type.
 205   llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F);
 206   llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty,
 207                                      llvm::DIFile *F);
 208   /// Get Objective-C object type.
 209   llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F);
 210   llvm::DIType *CreateType(const ObjCTypeParamType *Ty, llvm::DIFile *Unit);
 211
 212   llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F);
 213   llvm::DIType *CreateType(const ConstantMatrixType *Ty, llvm::DIFile *F);
 214   llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F);
 215   llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F);
 216   llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit);
 217   llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F);
 218   llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F);
 219   llvm::DIType *CreateType(const PipeType *Ty, llvm::DIFile *F);
 220   /// Get enumeration type.
 221   llvm::DIType *CreateEnumType(const EnumType *Ty);
 222   llvm::DIType *CreateTypeDefinition(const EnumType *Ty);
 223   /// Look up the completed type for a self pointer in the TypeCache and
 224   /// create a copy of it with the ObjectPointer and Artificial flags
 225   /// set. If the type is not cached, a new one is created. This should
 226   /// never happen though, since creating a type for the implicit self
 227   /// argument implies that we already parsed the interface definition
 228   /// and the ivar declarations in the implementation.
 229   llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty);
 230   /// @}
 231
 232   /// Get the type from the cache or return null type if it doesn't
 233   /// exist.
 234   llvm::DIType *getTypeOrNull(const QualType);
 235   /// Return the debug type for a C++ method.
 236   /// \arg CXXMethodDecl is of FunctionType. This function type is
 237   /// not updated to include implicit \c this pointer. Use this routine
 238   /// to get a method type which includes \c this pointer.
 239   llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method,
 240                                                 llvm::DIFile *F);
 241   llvm::DISubroutineType *
 242   getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func,
 243                                 llvm::DIFile *Unit);
 244   llvm::DISubroutineType *
 245   getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F);
 246   /// \return debug info descriptor for vtable.
 247   llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F);
 248
 249   /// \return namespace descriptor for the given namespace decl.
 250   llvm::DINamespace *getOrCreateNamespace(const NamespaceDecl *N);
 251   llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty,
 252                                       QualType PointeeTy, llvm::DIFile *F);
 253   llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache);
 254
 255   /// A helper function to create a subprogram for a single member
 256   /// function GlobalDecl.
 257   llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method,
 258                                               llvm::DIFile *F,
 259                                               llvm::DIType *RecordTy);
 260
 261   /// A helper function to collect debug info for C++ member
 262   /// functions. This is used while creating debug info entry for a
 263   /// Record.
 264   void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F,
 265                                  SmallVectorImpl<llvm::Metadata *> &E,
 266                                  llvm::DIType *T);
 267
 268   /// A helper function to collect debug info for C++ base
 269   /// classes. This is used while creating debug info entry for a
 270   /// Record.
 271   void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F,
 272                        SmallVectorImpl<llvm::Metadata *> &EltTys,
 273                        llvm::DIType *RecordTy);
 274
 275   /// Helper function for CollectCXXBases.
 276   /// Adds debug info entries for types in Bases that are not in SeenTypes.
 277   void CollectCXXBasesAux(
 278       const CXXRecordDecl *RD, llvm::DIFile *Unit,
 279       SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy,
 280       const CXXRecordDecl::base_class_const_range &Bases,
 281       llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> &SeenTypes,
 282       llvm::DINode::DIFlags StartingFlags);
 283
 284   /// Helper function that returns the llvm::DIType that the
 285   /// PreferredNameAttr attribute on \ref RD refers to. If no such
 286   /// attribute exists, returns nullptr.
 287   llvm::DIType *GetPreferredNameType(const CXXRecordDecl *RD,
 288                                      llvm::DIFile *Unit);
 289
 290   struct TemplateArgs {
 291     const TemplateParameterList *TList;
 292     llvm::ArrayRef<TemplateArgument> Args;
 293   };
 294   /// A helper function to collect template parameters.
 295   llvm::DINodeArray CollectTemplateParams(std::optional<TemplateArgs> Args,
 296                                           llvm::DIFile *Unit);
 297   /// A helper function to collect debug info for function template
 298   /// parameters.
 299   llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD,
 300                                                   llvm::DIFile *Unit);
 301
 302   /// A helper function to collect debug info for function template
 303   /// parameters.
 304   llvm::DINodeArray CollectVarTemplateParams(const VarDecl *VD,
 305                                              llvm::DIFile *Unit);
 306
 307   std::optional<TemplateArgs> GetTemplateArgs(const VarDecl *) const;
 308   std::optional<TemplateArgs> GetTemplateArgs(const RecordDecl *) const;
 309   std::optional<TemplateArgs> GetTemplateArgs(const FunctionDecl *) const;
 310
 311   /// A helper function to collect debug info for template
 312   /// parameters.
 313   llvm::DINodeArray CollectCXXTemplateParams(const RecordDecl *TS,
 314                                              llvm::DIFile *F);
 315
 316   /// A helper function to collect debug info for btf_decl_tag annotations.
 317   llvm::DINodeArray CollectBTFDeclTagAnnotations(const Decl *D);
 318
 319   llvm::DIType *createFieldType(StringRef name, QualType type,
 320                                 SourceLocation loc, AccessSpecifier AS,
 321                                 uint64_t offsetInBits, uint32_t AlignInBits,
 322                                 llvm::DIFile *tunit, llvm::DIScope *scope,
 323                                 const RecordDecl *RD = nullptr,
 324                                 llvm::DINodeArray Annotations = nullptr);
 325
 326   llvm::DIType *createFieldType(StringRef name, QualType type,
 327                                 SourceLocation loc, AccessSpecifier AS,
 328                                 uint64_t offsetInBits, llvm::DIFile *tunit,
 329                                 llvm::DIScope *scope,
 330                                 const RecordDecl *RD = nullptr) {
 331     return createFieldType(name, type, loc, AS, offsetInBits, 0, tunit, scope,
 332                            RD);
 333   }
 334
 335   /// Create new bit field member.
 336   llvm::DIDerivedType *createBitFieldType(const FieldDecl *BitFieldDecl,
 337                                           llvm::DIScope *RecordTy,
 338                                           const RecordDecl *RD);
 339
 340   /// Create type for binding declarations.
 341   llvm::DIType *CreateBindingDeclType(const BindingDecl *BD);
 342
 343   /// Create an anonnymous zero-size separator for bit-field-decl if needed on
 344   /// the target.
 345   llvm::DIDerivedType *createBitFieldSeparatorIfNeeded(
 346       const FieldDecl *BitFieldDecl, const llvm::DIDerivedType *BitFieldDI,
 347       llvm::ArrayRef<llvm::Metadata *> PreviousFieldsDI, const RecordDecl *RD);
 348
 349   /// Helpers for collecting fields of a record.
 350   /// @{
 351   void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,
 352                                  SmallVectorImpl<llvm::Metadata *> &E,
 353                                  llvm::DIType *RecordTy);
 354   llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var,
 355                                                llvm::DIType *RecordTy,
 356                                                const RecordDecl *RD);
 357   void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,
 358                                 llvm::DIFile *F,
 359                                 SmallVectorImpl<llvm::Metadata *> &E,
 360                                 llvm::DIType *RecordTy, const RecordDecl *RD);
 361   void CollectRecordNestedType(const TypeDecl *RD,
 362                                SmallVectorImpl<llvm::Metadata *> &E);
 363   void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F,
 364                            SmallVectorImpl<llvm::Metadata *> &E,
 365                            llvm::DICompositeType *RecordTy);
 366
 367   /// If the C++ class has vtable info then insert appropriate debug
 368   /// info entry in EltTys vector.
 369   void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F,
 370                          SmallVectorImpl<llvm::Metadata *> &EltTys);
 371   /// @}
 372
 373   /// Create a new lexical block node and push it on the stack.
 374   void CreateLexicalBlock(SourceLocation Loc);
 375
 376   /// If target-specific LLVM \p AddressSpace directly maps to target-specific
 377   /// DWARF address space, appends extended dereferencing mechanism to complex
 378   /// expression \p Expr. Otherwise, does nothing.
 379   ///
 380   /// Extended dereferencing mechanism is has the following format:
 381   ///     DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef
 382   void AppendAddressSpaceXDeref(unsigned AddressSpace,
 383                                 SmallVectorImpl<uint64_t> &Expr) const;
 384
 385   /// A helper function to collect debug info for the default elements of a
 386   /// block.
 387   ///
 388   /// \returns The next available field offset after the default elements.
 389   uint64_t collectDefaultElementTypesForBlockPointer(
 390       const BlockPointerType *Ty, llvm::DIFile *Unit,
 391       llvm::DIDerivedType *DescTy, unsigned LineNo,
 392       SmallVectorImpl<llvm::Metadata *> &EltTys);
 393
 394   /// A helper function to collect debug info for the default fields of a
 395   /// block.
 396   void collectDefaultFieldsForBlockLiteralDeclare(
 397       const CGBlockInfo &Block, const ASTContext &Context, SourceLocation Loc,
 398       const llvm::StructLayout &BlockLayout, llvm::DIFile *Unit,
 399       SmallVectorImpl<llvm::Metadata *> &Fields);
 400
 401 public:
 402   CGDebugInfo(CodeGenModule &CGM);
 403   ~CGDebugInfo();
 404
 405   void finalize();
 406
 407   /// Remap a given path with the current debug prefix map
 408   std::string remapDIPath(StringRef) const;
 409
 410   /// Register VLA size expression debug node with the qualified type.
 411   void registerVLASizeExpression(QualType Ty, llvm::Metadata *SizeExpr) {
 412     SizeExprCache[Ty] = SizeExpr;
 413   }
 414
 415   /// Module debugging: Support for building PCMs.
 416   /// @{
 417   /// Set the main CU's DwoId field to \p Signature.
 418   void setDwoId(uint64_t Signature);
 419
 420   /// When generating debug information for a clang module or
 421   /// precompiled header, this module map will be used to determine
 422   /// the module of origin of each Decl.
 423   void setModuleMap(ModuleMap &MMap) { ClangModuleMap = &MMap; }
 424
 425   /// When generating debug information for a clang module or
 426   /// precompiled header, this module map will be used to determine
 427   /// the module of origin of each Decl.
 428   void setPCHDescriptor(ASTSourceDescriptor PCH) { PCHDescriptor = PCH; }
 429   /// @}
 430
 431   /// Update the current source location. If \arg loc is invalid it is
 432   /// ignored.
 433   void setLocation(SourceLocation Loc);
 434
 435   /// Return the current source location. This does not necessarily correspond
 436   /// to the IRBuilder's current DebugLoc.
 437   SourceLocation getLocation() const { return CurLoc; }
 438
 439   /// Update the current inline scope. All subsequent calls to \p EmitLocation
 440   /// will create a location with this inlinedAt field.
 441   void setInlinedAt(llvm::MDNode *InlinedAt) { CurInlinedAt = InlinedAt; }
 442
 443   /// \return the current inline scope.
 444   llvm::MDNode *getInlinedAt() const { return CurInlinedAt; }
 445
 446   // Converts a SourceLocation to a DebugLoc
 447   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Loc);
 448
 449   /// Emit metadata to indicate a change in line/column information in
 450   /// the source file. If the location is invalid, the previous
 451   /// location will be reused.
 452   void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc);
 453
 454   QualType getFunctionType(const FunctionDecl *FD, QualType RetTy,
 455                            const SmallVectorImpl<const VarDecl *> &Args);
 456
 457   /// Emit a call to llvm.dbg.function.start to indicate
 458   /// start of a new function.
 459   /// \param Loc       The location of the function header.
 460   /// \param ScopeLoc  The location of the function body.
 461   void emitFunctionStart(GlobalDecl GD, SourceLocation Loc,
 462                          SourceLocation ScopeLoc, QualType FnType,
 463                          llvm::Function *Fn, bool CurFnIsThunk);
 464
 465   /// Start a new scope for an inlined function.
 466   void EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD);
 467   /// End an inlined function scope.
 468   void EmitInlineFunctionEnd(CGBuilderTy &Builder);
 469
 470   /// Emit debug info for a function declaration.
 471   /// \p Fn is set only when a declaration for a debug call site gets created.
 472   void EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 473                         QualType FnType, llvm::Function *Fn = nullptr);
 474
 475   /// Emit debug info for an extern function being called.
 476   /// This is needed for call site debug info.
 477   void EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
 478                                QualType CalleeType,
 479                                const FunctionDecl *CalleeDecl);
 480
 481   /// Constructs the debug code for exiting a function.
 482   void EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn);
 483
 484   /// Emit metadata to indicate the beginning of a new lexical block
 485   /// and push the block onto the stack.
 486   void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);
 487
 488   /// Emit metadata to indicate the end of a new lexical block and pop
 489   /// the current block.
 490   void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);
 491
 492   /// Emit call to \c llvm.dbg.declare for an automatic variable
 493   /// declaration.
 494   /// Returns a pointer to the DILocalVariable associated with the
 495   /// llvm.dbg.declare, or nullptr otherwise.
 496   llvm::DILocalVariable *
 497   EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,
 498                             CGBuilderTy &Builder,
 499                             const bool UsePointerValue = false);
 500
 501   /// Emit call to \c llvm.dbg.label for an label.
 502   void EmitLabel(const LabelDecl *D, CGBuilderTy &Builder);
 503
 504   /// Emit call to \c llvm.dbg.declare for an imported variable
 505   /// declaration in a block.
 506   void EmitDeclareOfBlockDeclRefVariable(
 507       const VarDecl *variable, llvm::Value *storage, CGBuilderTy &Builder,
 508       const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint = nullptr);
 509
 510   /// Emit call to \c llvm.dbg.declare for an argument variable
 511   /// declaration.
 512   llvm::DILocalVariable *
 513   EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI, unsigned ArgNo,
 514                            CGBuilderTy &Builder, bool UsePointerValue = false);
 515
 516   /// Emit call to \c llvm.dbg.declare for the block-literal argument
 517   /// to a block invocation function.
 518   void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
 519                                             StringRef Name, unsigned ArgNo,
 520                                             llvm::AllocaInst *LocalAddr,
 521                                             CGBuilderTy &Builder);
 522
 523   /// Emit information about a global variable.
 524   void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
 525
 526   /// Emit a constant global variable's debug info.
 527   void EmitGlobalVariable(const ValueDecl *VD, const APValue &Init);
 528
 529   /// Emit information about an external variable.
 530   void EmitExternalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
 531
 532   /// Emit information about global variable alias.
 533   void EmitGlobalAlias(const llvm::GlobalValue *GV, const GlobalDecl Decl);
 534
 535   /// Emit C++ using directive.
 536   void EmitUsingDirective(const UsingDirectiveDecl &UD);
 537
 538   /// Emit the type explicitly casted to.
 539   void EmitExplicitCastType(QualType Ty);
 540
 541   /// Emit the type even if it might not be used.
 542   void EmitAndRetainType(QualType Ty);
 543
 544   /// Emit a shadow decl brought in by a using or using-enum
 545   void EmitUsingShadowDecl(const UsingShadowDecl &USD);
 546
 547   /// Emit C++ using declaration.
 548   void EmitUsingDecl(const UsingDecl &UD);
 549
 550   /// Emit C++ using-enum declaration.
 551   void EmitUsingEnumDecl(const UsingEnumDecl &UD);
 552
 553   /// Emit an @import declaration.
 554   void EmitImportDecl(const ImportDecl &ID);
 555
 556   /// DebugInfo isn't attached to string literals by default. While certain
 557   /// aspects of debuginfo aren't useful for string literals (like a name), it's
 558   /// nice to be able to symbolize the line and column information. This is
 559   /// especially useful for sanitizers, as it allows symbolization of
 560   /// heap-buffer-overflows on constant strings.
 561   void AddStringLiteralDebugInfo(llvm::GlobalVariable *GV,
 562                                  const StringLiteral *S);
 563
 564   /// Emit C++ namespace alias.
 565   llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA);
 566
 567   /// Emit record type's standalone debug info.
 568   llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L);
 569
 570   /// Emit an Objective-C interface type standalone debug info.
 571   llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);
 572
 573   /// Emit standalone debug info for a type.
 574   llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);
 575
 576   /// Add heapallocsite metadata for MSAllocator calls.
 577   void addHeapAllocSiteMetadata(llvm::CallBase *CallSite, QualType AllocatedTy,
 578                                 SourceLocation Loc);
 579
 580   void completeType(const EnumDecl *ED);
 581   void completeType(const RecordDecl *RD);
 582   void completeRequiredType(const RecordDecl *RD);
 583   void completeClassData(const RecordDecl *RD);
 584   void completeClass(const RecordDecl *RD);
 585
 586   void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);
 587   void completeUnusedClass(const CXXRecordDecl &D);
 588
 589   /// Create debug info for a macro defined by a #define directive or a macro
 590   /// undefined by a #undef directive.
 591   llvm::DIMacro *CreateMacro(llvm::DIMacroFile *Parent, unsigned MType,
 592                              SourceLocation LineLoc, StringRef Name,
 593                              StringRef Value);
 594
 595   /// Create debug info for a file referenced by an #include directive.
 596   llvm::DIMacroFile *CreateTempMacroFile(llvm::DIMacroFile *Parent,
 597                                          SourceLocation LineLoc,
 598                                          SourceLocation FileLoc);
 599
 600   Param2DILocTy &getParamDbgMappings() { return ParamDbgMappings; }
 601   ParamDecl2StmtTy &getCoroutineParameterMappings() {
 602     return CoroutineParameterMappings;
 603   }
 604
 605 private:
 606   /// Emit call to llvm.dbg.declare for a variable declaration.
 607   /// Returns a pointer to the DILocalVariable associated with the
 608   /// llvm.dbg.declare, or nullptr otherwise.
 609   llvm::DILocalVariable *EmitDeclare(const VarDecl *decl, llvm::Value *AI,
 610                                      std::optional<unsigned> ArgNo,
 611                                      CGBuilderTy &Builder,
 612                                      const bool UsePointerValue = false);
 613
 614   /// Emit call to llvm.dbg.declare for a binding declaration.
 615   /// Returns a pointer to the DILocalVariable associated with the
 616   /// llvm.dbg.declare, or nullptr otherwise.
 617   llvm::DILocalVariable *EmitDeclare(const BindingDecl *decl, llvm::Value *AI,
 618                                      std::optional<unsigned> ArgNo,
 619                                      CGBuilderTy &Builder,
 620                                      const bool UsePointerValue = false);
 621
 622   struct BlockByRefType {
 623     /// The wrapper struct used inside the __block_literal struct.
 624     llvm::DIType *BlockByRefWrapper;
 625     /// The type as it appears in the source code.
 626     llvm::DIType *WrappedType;
 627   };
 628
 629   std::string GetName(const Decl*, bool Qualified = false) const;
 630
 631   /// Build up structure info for the byref.  See \a BuildByRefType.
 632   BlockByRefType EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
 633                                               uint64_t *OffSet);
 634
 635   /// Get context info for the DeclContext of \p Decl.
 636   llvm::DIScope *getDeclContextDescriptor(const Decl *D);
 637   /// Get context info for a given DeclContext \p Decl.
 638   llvm::DIScope *getContextDescriptor(const Decl *Context,
 639                                       llvm::DIScope *Default);
 640
 641   llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl);
 642
 643   /// Create a forward decl for a RecordType in a given context.
 644   llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *,
 645                                                   llvm::DIScope *);
 646
 647   /// Return current directory name.
 648   StringRef getCurrentDirname();
 649
 650   /// Create new compile unit.
 651   void CreateCompileUnit();
 652
 653   /// Compute the file checksum debug info for input file ID.
 654   std::optional<llvm::DIFile::ChecksumKind>
 655   computeChecksum(FileID FID, SmallString<64> &Checksum) const;
 656
 657   /// Get the source of the given file ID.
 658   std::optional<StringRef> getSource(const SourceManager &SM, FileID FID);
 659
 660   /// Convenience function to get the file debug info descriptor for the input
 661   /// location.
 662   llvm::DIFile *getOrCreateFile(SourceLocation Loc);
 663
 664   /// Create a file debug info descriptor for a source file.
 665   llvm::DIFile *
 666   createFile(StringRef FileName,
 667              std::optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo,
 668              std::optional<StringRef> Source);
 669
 670   /// Get the type from the cache or create a new type if necessary.
 671   llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg);
 672
 673   /// Get a reference to a clang module.  If \p CreateSkeletonCU is true,
 674   /// this also creates a split dwarf skeleton compile unit.
 675   llvm::DIModule *getOrCreateModuleRef(ASTSourceDescriptor Mod,
 676                                        bool CreateSkeletonCU);
 677
 678   /// DebugTypeExtRefs: If \p D originated in a clang module, return it.
 679   llvm::DIModule *getParentModuleOrNull(const Decl *D);
 680
 681   /// Get the type from the cache or create a new partial type if
 682   /// necessary.
 683   llvm::DICompositeType *getOrCreateLimitedType(const RecordType *Ty);
 684
 685   /// Create type metadata for a source language type.
 686   llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg);
 687
 688   /// Create new member and increase Offset by FType's size.
 689   llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType,
 690                                  StringRef Name, uint64_t *Offset);
 691
 692   /// Retrieve the DIDescriptor, if any, for the canonical form of this
 693   /// declaration.
 694   llvm::DINode *getDeclarationOrDefinition(const Decl *D);
 695
 696   /// \return debug info descriptor to describe method
 697   /// declaration for the given method definition.
 698   llvm::DISubprogram *getFunctionDeclaration(const Decl *D);
 699
 700   /// \return          debug info descriptor to the describe method declaration
 701   ///                  for the given method definition.
 702   /// \param FnType    For Objective-C methods, their type.
 703   /// \param LineNo    The declaration's line number.
 704   /// \param Flags     The DIFlags for the method declaration.
 705   /// \param SPFlags   The subprogram-spcific flags for the method declaration.
 706   llvm::DISubprogram *
 707   getObjCMethodDeclaration(const Decl *D, llvm::DISubroutineType *FnType,
 708                            unsigned LineNo, llvm::DINode::DIFlags Flags,
 709                            llvm::DISubprogram::DISPFlags SPFlags);
 710
 711   /// \return debug info descriptor to describe in-class static data
 712   /// member declaration for the given out-of-class definition.  If D
 713   /// is an out-of-class definition of a static data member of a
 714   /// class, find its corresponding in-class declaration.
 715   llvm::DIDerivedType *
 716   getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);
 717
 718   /// Helper that either creates a forward declaration or a stub.
 719   llvm::DISubprogram *getFunctionFwdDeclOrStub(GlobalDecl GD, bool Stub);
 720
 721   /// Create a subprogram describing the forward declaration
 722   /// represented in the given FunctionDecl wrapped in a GlobalDecl.
 723   llvm::DISubprogram *getFunctionForwardDeclaration(GlobalDecl GD);
 724
 725   /// Create a DISubprogram describing the function
 726   /// represented in the given FunctionDecl wrapped in a GlobalDecl.
 727   llvm::DISubprogram *getFunctionStub(GlobalDecl GD);
 728
 729   /// Create a global variable describing the forward declaration
 730   /// represented in the given VarDecl.
 731   llvm::DIGlobalVariable *
 732   getGlobalVariableForwardDeclaration(const VarDecl *VD);
 733
 734   /// Return a global variable that represents one of the collection of global
 735   /// variables created for an anonmyous union.
 736   ///
 737   /// Recursively collect all of the member fields of a global
 738   /// anonymous decl and create static variables for them. The first
 739   /// time this is called it needs to be on a union and then from
 740   /// there we can have additional unnamed fields.
 741   llvm::DIGlobalVariableExpression *
 742   CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit,
 743                          unsigned LineNo, StringRef LinkageName,
 744                          llvm::GlobalVariable *Var, llvm::DIScope *DContext);
 745
 746
 747   /// Return flags which enable debug info emission for call sites, provided
 748   /// that it is supported and enabled.
 749   llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;
 750
 751   /// Get the printing policy for producing names for debug info.
 752   PrintingPolicy getPrintingPolicy() const;
 753
 754   /// Get function name for the given FunctionDecl. If the name is
 755   /// constructed on demand (e.g., C++ destructor) then the name is
 756   /// stored on the side.
 757   StringRef getFunctionName(const FunctionDecl *FD);
 758
 759   /// Returns the unmangled name of an Objective-C method.
 760   /// This is the display name for the debugging info.
 761   StringRef getObjCMethodName(const ObjCMethodDecl *FD);
 762
 763   /// Return selector name. This is used for debugging
 764   /// info.
 765   StringRef getSelectorName(Selector S);
 766
 767   /// Get class name including template argument list.
 768   StringRef getClassName(const RecordDecl *RD);
 769
 770   /// Get the vtable name for the given class.
 771   StringRef getVTableName(const CXXRecordDecl *Decl);
 772
 773   /// Get the name to use in the debug info for a dynamic initializer or atexit
 774   /// stub function.
 775   StringRef getDynamicInitializerName(const VarDecl *VD,
 776                                       DynamicInitKind StubKind,
 777                                       llvm::Function *InitFn);
 778
 779   /// Get line number for the location. If location is invalid
 780   /// then use current location.
 781   unsigned getLineNumber(SourceLocation Loc);
 782
 783   /// Get column number for the location. If location is
 784   /// invalid then use current location.
 785   /// \param Force  Assume DebugColumnInfo option is true.
 786   unsigned getColumnNumber(SourceLocation Loc, bool Force = false);
 787
 788   /// Collect various properties of a FunctionDecl.
 789   /// \param GD  A GlobalDecl whose getDecl() must return a FunctionDecl.
 790   void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
 791                                 StringRef &Name, StringRef &LinkageName,
 792                                 llvm::DIScope *&FDContext,
 793                                 llvm::DINodeArray &TParamsArray,
 794                                 llvm::DINode::DIFlags &Flags);
 795
 796   /// Collect various properties of a VarDecl.
 797   void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
 798                            unsigned &LineNo, QualType &T, StringRef &Name,
 799                            StringRef &LinkageName,
 800                            llvm::MDTuple *&TemplateParameters,
 801                            llvm::DIScope *&VDContext);
 802
 803   /// Allocate a copy of \p A using the DebugInfoNames allocator
 804   /// and return a reference to it. If multiple arguments are given the strings
 805   /// are concatenated.
 806   StringRef internString(StringRef A, StringRef B = StringRef()) {
 807     char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());
 808     if (!A.empty())
 809       std::memcpy(Data, A.data(), A.size());
 810     if (!B.empty())
 811       std::memcpy(Data + A.size(), B.data(), B.size());
 812     return StringRef(Data, A.size() + B.size());
 813   }
 814 };
 815
 816 /// A scoped helper to set the current debug location to the specified
 817 /// location or preferred location of the specified Expr.
 818 class ApplyDebugLocation {
 819 private:
 820   void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false);
 821   ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty,
 822                      SourceLocation TemporaryLocation);
 823
 824   llvm::DebugLoc OriginalLocation;
 825   CodeGenFunction *CGF;
 826
 827 public:
 828   /// Set the location to the (valid) TemporaryLocation.
 829   ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);
 830   ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);
 831   ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);
 832   ApplyDebugLocation(ApplyDebugLocation &&Other) : CGF(Other.CGF) {
 833     Other.CGF = nullptr;
 834   }
 835
 836   // Define copy assignment operator.
 837   ApplyDebugLocation &operator=(ApplyDebugLocation &&Other) {
 838     if (this != &Other) {
 839       CGF = Other.CGF;
 840       Other.CGF = nullptr;
 841     }
 842     return *this;
 843   }
 844
 845   ~ApplyDebugLocation();
 846
 847   /// Apply TemporaryLocation if it is valid. Otherwise switch
 848   /// to an artificial debug location that has a valid scope, but no
 849   /// line information.
 850   ///
 851   /// Artificial locations are useful when emitting compiler-generated
 852   /// helper functions that have no source location associated with
 853   /// them. The DWARF specification allows the compiler to use the
 854   /// special line number 0 to indicate code that can not be
 855   /// attributed to any source location. Note that passing an empty
 856   /// SourceLocation to CGDebugInfo::setLocation() will result in the
 857   /// last valid location being reused.
 858   static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) {
 859     return ApplyDebugLocation(CGF, false, SourceLocation());
 860   }
 861   /// Apply TemporaryLocation if it is valid. Otherwise switch
 862   /// to an artificial debug location that has a valid scope, but no
 863   /// line information.
 864   static ApplyDebugLocation
 865   CreateDefaultArtificial(CodeGenFunction &CGF,
 866                           SourceLocation TemporaryLocation) {
 867     return ApplyDebugLocation(CGF, false, TemporaryLocation);
 868   }
 869
 870   /// Set the IRBuilder to not attach debug locations.  Note that
 871   /// passing an empty SourceLocation to \a CGDebugInfo::setLocation()
 872   /// will result in the last valid location being reused.  Note that
 873   /// all instructions that do not have a location at the beginning of
 874   /// a function are counted towards to function prologue.
 875   static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) {
 876     return ApplyDebugLocation(CGF, true, SourceLocation());
 877   }
 878 };
 879
 880 /// A scoped helper to set the current debug location to an inlined location.
 881 class ApplyInlineDebugLocation {
 882   SourceLocation SavedLocation;
 883   CodeGenFunction *CGF;
 884
 885 public:
 886   /// Set up the CodeGenFunction's DebugInfo to produce inline locations for the
 887   /// function \p InlinedFn. The current debug location becomes the inlined call
 888   /// site of the inlined function.
 889   ApplyInlineDebugLocation(CodeGenFunction &CGF, GlobalDecl InlinedFn);
 890   /// Restore everything back to the original state.
 891   ~ApplyInlineDebugLocation();
 892 };
 893
 894 } // namespace CodeGen
 895 } // namespace clang
 896
 897 #endif // LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H