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/ASTSourceDescriptor.h"
  24 #include "clang/Basic/CodeGenOptions.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 <map>
  33 #include <optional>
  34 #include <string>
  35
  36 namespace llvm {
  37 class MDNode;
  38 }
  39
  40 namespace clang {
  41 class ClassTemplateSpecializationDecl;
  42 class GlobalDecl;
  43 class Module;
  44 class ModuleMap;
  45 class ObjCInterfaceDecl;
  46 class UsingDecl;
  47 class VarDecl;
  48 enum class DynamicInitKind : unsigned;
  49
  50 namespace CodeGen {
  51 class CodeGenModule;
  52 class CodeGenFunction;
  53 class CGBlockInfo;
  54
  55 /// This class gathers all debug information during compilation and is
  56 /// responsible for emitting to llvm globals or pass directly to the
  57 /// backend.
  58 class CGDebugInfo {
  59   friend class ApplyDebugLocation;
  60   friend class SaveAndRestoreLocation;
  61   CodeGenModule &CGM;
  62   const llvm::codegenoptions::DebugInfoKind DebugKind;
  63   bool DebugTypeExtRefs;
  64   llvm::DIBuilder DBuilder;
  65   llvm::DICompileUnit *TheCU = nullptr;
  66   ModuleMap *ClangModuleMap = nullptr;
  67   ASTSourceDescriptor PCHDescriptor;
  68   SourceLocation CurLoc;
  69   llvm::MDNode *CurInlinedAt = nullptr;
  70   llvm::DIType *VTablePtrType = nullptr;
  71   llvm::DIType *ClassTy = nullptr;
  72   llvm::DICompositeType *ObjTy = nullptr;
  73   llvm::DIType *SelTy = nullptr;
  74 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \
  75   llvm::DIType *SingletonId = nullptr;
  76 #include "clang/Basic/OpenCLImageTypes.def"
  77   llvm::DIType *OCLSamplerDITy = nullptr;
  78   llvm::DIType *OCLEventDITy = nullptr;
  79   llvm::DIType *OCLClkEventDITy = nullptr;
  80   llvm::DIType *OCLQueueDITy = nullptr;
  81   llvm::DIType *OCLNDRangeDITy = nullptr;
  82   llvm::DIType *OCLReserveIDDITy = nullptr;
  83 #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
  84   llvm::DIType *Id##Ty = nullptr;
  85 #include "clang/Basic/OpenCLExtensionTypes.def"
  86 #define WASM_TYPE(Name, Id, SingletonId) llvm::DIType *SingletonId = nullptr;
  87 #include "clang/Basic/WebAssemblyReferenceTypes.def"
  88 #define AMDGPU_TYPE(Name, Id, SingletonId) llvm::DIType *SingletonId = nullptr;
  89 #include "clang/Basic/AMDGPUTypes.def"
  90
  91   /// Cache of previously constructed Types.
  92   llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache;
  93
  94   /// Cache that maps VLA types to size expressions for that type,
  95   /// represented by instantiated Metadata nodes.
  96   llvm::SmallDenseMap<QualType, llvm::Metadata *> SizeExprCache;
  97
  98   /// Callbacks to use when printing names and types.
  99   class PrintingCallbacks final : public clang::PrintingCallbacks {
 100     const CGDebugInfo &Self;
 101
 102   public:
 103     PrintingCallbacks(const CGDebugInfo &Self) : Self(Self) {}
 104     std::string remapPath(StringRef Path) const override {
 105       return Self.remapDIPath(Path);
 106     }
 107   };
 108   PrintingCallbacks PrintCB = {*this};
 109
 110   struct ObjCInterfaceCacheEntry {
 111     const ObjCInterfaceType *Type;
 112     llvm::DIType *Decl;
 113     llvm::DIFile *Unit;
 114     ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl,
 115                             llvm::DIFile *Unit)
 116         : Type(Type), Decl(Decl), Unit(Unit) {}
 117   };
 118
 119   /// Cache of previously constructed interfaces which may change.
 120   llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;
 121
 122   /// Cache of forward declarations for methods belonging to the interface.
 123   /// The extra bit on the DISubprogram specifies whether a method is
 124   /// "objc_direct".
 125   llvm::DenseMap<const ObjCInterfaceDecl *,
 126                  std::vector<llvm::PointerIntPair<llvm::DISubprogram *, 1>>>
 127       ObjCMethodCache;
 128
 129   /// Cache of references to clang modules and precompiled headers.
 130   llvm::DenseMap<const Module *, llvm::TrackingMDRef> ModuleCache;
 131
 132   /// List of interfaces we want to keep even if orphaned.
 133   std::vector<void *> RetainedTypes;
 134
 135   /// Cache of forward declared types to RAUW at the end of compilation.
 136   std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap;
 137
 138   /// Cache of replaceable forward declarations (functions and
 139   /// variables) to RAUW at the end of compilation.
 140   std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>>
 141       FwdDeclReplaceMap;
 142
 143   /// Keep track of our current nested lexical block.
 144   std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;
 145   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;
 146   /// Keep track of LexicalBlockStack counter at the beginning of a
 147   /// function. This is used to pop unbalanced regions at the end of a
 148   /// function.
 149   std::vector<unsigned> FnBeginRegionCount;
 150
 151   /// This is a storage for names that are constructed on demand. For
 152   /// example, C++ destructors, C++ operators etc..
 153   llvm::BumpPtrAllocator DebugInfoNames;
 154   StringRef CWDName;
 155
 156   llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;
 157   llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;
 158   /// Cache declarations relevant to DW_TAG_imported_declarations (C++
 159   /// using declarations and global alias variables) that aren't covered
 160   /// by other more specific caches.
 161   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache;
 162   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> ImportedDeclCache;
 163   llvm::DenseMap<const NamespaceDecl *, llvm::TrackingMDRef> NamespaceCache;
 164   llvm::DenseMap<const NamespaceAliasDecl *, llvm::TrackingMDRef>
 165       NamespaceAliasCache;
 166   llvm::DenseMap<const Decl *, llvm::TypedTrackingMDRef<llvm::DIDerivedType>>
 167       StaticDataMemberCache;
 168
 169   using ParamDecl2StmtTy = llvm::DenseMap<const ParmVarDecl *, const Stmt *>;
 170   using Param2DILocTy =
 171       llvm::DenseMap<const ParmVarDecl *, llvm::DILocalVariable *>;
 172
 173   /// The key is coroutine real parameters, value is coroutine move parameters.
 174   ParamDecl2StmtTy CoroutineParameterMappings;
 175   /// The key is coroutine real parameters, value is DIVariable in LLVM IR.
 176   Param2DILocTy ParamDbgMappings;
 177
 178   /// Helper functions for getOrCreateType.
 179   /// @{
 180   /// Currently the checksum of an interface includes the number of
 181   /// ivars and property accessors.
 182   llvm::DIType *CreateType(const BuiltinType *Ty);
 183   llvm::DIType *CreateType(const ComplexType *Ty);
 184   llvm::DIType *CreateType(const BitIntType *Ty);
 185   llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg);
 186   llvm::DIType *CreateQualifiedType(const FunctionProtoType *Ty,
 187                                     llvm::DIFile *Fg);
 188   llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg);
 189   llvm::DIType *CreateType(const TemplateSpecializationType *Ty,
 190                            llvm::DIFile *Fg);
 191   llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F);
 192   llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F);
 193   llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F);
 194   llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F);
 195   /// Get structure or union type.
 196   llvm::DIType *CreateType(const RecordType *Tyg);
 197
 198   /// Create definition for the specified 'Ty'.
 199   ///
 200   /// \returns A pair of 'llvm::DIType's. The first is the definition
 201   /// of the 'Ty'. The second is the type specified by the preferred_name
 202   /// attribute on 'Ty', which can be a nullptr if no such attribute
 203   /// exists.
 204   std::pair<llvm::DIType *, llvm::DIType *>
 205   CreateTypeDefinition(const RecordType *Ty);
 206   llvm::DICompositeType *CreateLimitedType(const RecordType *Ty);
 207   void CollectContainingType(const CXXRecordDecl *RD,
 208                              llvm::DICompositeType *CT);
 209   /// Get Objective-C interface type.
 210   llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F);
 211   llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty,
 212                                      llvm::DIFile *F);
 213   /// Get Objective-C object type.
 214   llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F);
 215   llvm::DIType *CreateType(const ObjCTypeParamType *Ty, llvm::DIFile *Unit);
 216
 217   llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F);
 218   llvm::DIType *CreateType(const ConstantMatrixType *Ty, llvm::DIFile *F);
 219   llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F);
 220   llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F);
 221   llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit);
 222   llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F);
 223   llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F);
 224   llvm::DIType *CreateType(const PipeType *Ty, llvm::DIFile *F);
 225   /// Get enumeration type.
 226   llvm::DIType *CreateEnumType(const EnumType *Ty);
 227   llvm::DIType *CreateTypeDefinition(const EnumType *Ty);
 228   /// Look up the completed type for a self pointer in the TypeCache and
 229   /// create a copy of it with the ObjectPointer and Artificial flags
 230   /// set. If the type is not cached, a new one is created. This should
 231   /// never happen though, since creating a type for the implicit self
 232   /// argument implies that we already parsed the interface definition
 233   /// and the ivar declarations in the implementation.
 234   llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty);
 235   /// @}
 236
 237   /// Get the type from the cache or return null type if it doesn't
 238   /// exist.
 239   llvm::DIType *getTypeOrNull(const QualType);
 240   /// Return the debug type for a C++ method.
 241   /// \arg CXXMethodDecl is of FunctionType. This function type is
 242   /// not updated to include implicit \c this pointer. Use this routine
 243   /// to get a method type which includes \c this pointer.
 244   llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method,
 245                                                 llvm::DIFile *F);
 246   llvm::DISubroutineType *
 247   getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func,
 248                                 llvm::DIFile *Unit);
 249   llvm::DISubroutineType *
 250   getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F);
 251   /// \return debug info descriptor for vtable.
 252   llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F);
 253
 254   /// \return namespace descriptor for the given namespace decl.
 255   llvm::DINamespace *getOrCreateNamespace(const NamespaceDecl *N);
 256   llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty,
 257                                       QualType PointeeTy, llvm::DIFile *F);
 258   llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache);
 259
 260   /// A helper function to create a subprogram for a single member
 261   /// function GlobalDecl.
 262   llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method,
 263                                               llvm::DIFile *F,
 264                                               llvm::DIType *RecordTy);
 265
 266   /// A helper function to collect debug info for C++ member
 267   /// functions. This is used while creating debug info entry for a
 268   /// Record.
 269   void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F,
 270                                  SmallVectorImpl<llvm::Metadata *> &E,
 271                                  llvm::DIType *T);
 272
 273   /// A helper function to collect debug info for C++ base
 274   /// classes. This is used while creating debug info entry for a
 275   /// Record.
 276   void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F,
 277                        SmallVectorImpl<llvm::Metadata *> &EltTys,
 278                        llvm::DIType *RecordTy);
 279
 280   /// Helper function for CollectCXXBases.
 281   /// Adds debug info entries for types in Bases that are not in SeenTypes.
 282   void CollectCXXBasesAux(
 283       const CXXRecordDecl *RD, llvm::DIFile *Unit,
 284       SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy,
 285       const CXXRecordDecl::base_class_const_range &Bases,
 286       llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> &SeenTypes,
 287       llvm::DINode::DIFlags StartingFlags);
 288
 289   /// Helper function that returns the llvm::DIType that the
 290   /// PreferredNameAttr attribute on \ref RD refers to. If no such
 291   /// attribute exists, returns nullptr.
 292   llvm::DIType *GetPreferredNameType(const CXXRecordDecl *RD,
 293                                      llvm::DIFile *Unit);
 294
 295   struct TemplateArgs {
 296     const TemplateParameterList *TList;
 297     llvm::ArrayRef<TemplateArgument> Args;
 298   };
 299   /// A helper function to collect template parameters.
 300   llvm::DINodeArray CollectTemplateParams(std::optional<TemplateArgs> Args,
 301                                           llvm::DIFile *Unit);
 302   /// A helper function to collect debug info for function template
 303   /// parameters.
 304   llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD,
 305                                                   llvm::DIFile *Unit);
 306
 307   /// A helper function to collect debug info for function template
 308   /// parameters.
 309   llvm::DINodeArray CollectVarTemplateParams(const VarDecl *VD,
 310                                              llvm::DIFile *Unit);
 311
 312   std::optional<TemplateArgs> GetTemplateArgs(const VarDecl *) const;
 313   std::optional<TemplateArgs> GetTemplateArgs(const RecordDecl *) const;
 314   std::optional<TemplateArgs> GetTemplateArgs(const FunctionDecl *) const;
 315
 316   /// A helper function to collect debug info for template
 317   /// parameters.
 318   llvm::DINodeArray CollectCXXTemplateParams(const RecordDecl *TS,
 319                                              llvm::DIFile *F);
 320
 321   /// A helper function to collect debug info for btf_decl_tag annotations.
 322   llvm::DINodeArray CollectBTFDeclTagAnnotations(const Decl *D);
 323
 324   llvm::DIType *createFieldType(StringRef name, QualType type,
 325                                 SourceLocation loc, AccessSpecifier AS,
 326                                 uint64_t offsetInBits, uint32_t AlignInBits,
 327                                 llvm::DIFile *tunit, llvm::DIScope *scope,
 328                                 const RecordDecl *RD = nullptr,
 329                                 llvm::DINodeArray Annotations = nullptr);
 330
 331   llvm::DIType *createFieldType(StringRef name, QualType type,
 332                                 SourceLocation loc, AccessSpecifier AS,
 333                                 uint64_t offsetInBits, llvm::DIFile *tunit,
 334                                 llvm::DIScope *scope,
 335                                 const RecordDecl *RD = nullptr) {
 336     return createFieldType(name, type, loc, AS, offsetInBits, 0, tunit, scope,
 337                            RD);
 338   }
 339
 340   /// Create new bit field member.
 341   llvm::DIDerivedType *createBitFieldType(const FieldDecl *BitFieldDecl,
 342                                           llvm::DIScope *RecordTy,
 343                                           const RecordDecl *RD);
 344
 345   /// Create an anonnymous zero-size separator for bit-field-decl if needed on
 346   /// the target.
 347   llvm::DIDerivedType *createBitFieldSeparatorIfNeeded(
 348       const FieldDecl *BitFieldDecl, const llvm::DIDerivedType *BitFieldDI,
 349       llvm::ArrayRef<llvm::Metadata *> PreviousFieldsDI, const RecordDecl *RD);
 350
 351   /// A cache that maps names of artificial inlined functions to subprograms.
 352   llvm::StringMap<llvm::DISubprogram *> InlinedTrapFuncMap;
 353
 354   /// A function that returns the subprogram corresponding to the artificial
 355   /// inlined function for traps.
 356   llvm::DISubprogram *createInlinedTrapSubprogram(StringRef FuncName,
 357                                                   llvm::DIFile *FileScope);
 358
 359   /// Helpers for collecting fields of a record.
 360   /// @{
 361   void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,
 362                                  SmallVectorImpl<llvm::Metadata *> &E,
 363                                  llvm::DIType *RecordTy);
 364   llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var,
 365                                                llvm::DIType *RecordTy,
 366                                                const RecordDecl *RD);
 367   void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,
 368                                 llvm::DIFile *F,
 369                                 SmallVectorImpl<llvm::Metadata *> &E,
 370                                 llvm::DIType *RecordTy, const RecordDecl *RD);
 371   void CollectRecordNestedType(const TypeDecl *RD,
 372                                SmallVectorImpl<llvm::Metadata *> &E);
 373   void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F,
 374                            SmallVectorImpl<llvm::Metadata *> &E,
 375                            llvm::DICompositeType *RecordTy);
 376
 377   /// If the C++ class has vtable info then insert appropriate debug
 378   /// info entry in EltTys vector.
 379   void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F,
 380                          SmallVectorImpl<llvm::Metadata *> &EltTys);
 381   /// @}
 382
 383   /// Create a new lexical block node and push it on the stack.
 384   void CreateLexicalBlock(SourceLocation Loc);
 385
 386   /// If target-specific LLVM \p AddressSpace directly maps to target-specific
 387   /// DWARF address space, appends extended dereferencing mechanism to complex
 388   /// expression \p Expr. Otherwise, does nothing.
 389   ///
 390   /// Extended dereferencing mechanism is has the following format:
 391   ///     DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef
 392   void AppendAddressSpaceXDeref(unsigned AddressSpace,
 393                                 SmallVectorImpl<uint64_t> &Expr) const;
 394
 395   /// A helper function to collect debug info for the default elements of a
 396   /// block.
 397   ///
 398   /// \returns The next available field offset after the default elements.
 399   uint64_t collectDefaultElementTypesForBlockPointer(
 400       const BlockPointerType *Ty, llvm::DIFile *Unit,
 401       llvm::DIDerivedType *DescTy, unsigned LineNo,
 402       SmallVectorImpl<llvm::Metadata *> &EltTys);
 403
 404   /// A helper function to collect debug info for the default fields of a
 405   /// block.
 406   void collectDefaultFieldsForBlockLiteralDeclare(
 407       const CGBlockInfo &Block, const ASTContext &Context, SourceLocation Loc,
 408       const llvm::StructLayout &BlockLayout, llvm::DIFile *Unit,
 409       SmallVectorImpl<llvm::Metadata *> &Fields);
 410
 411 public:
 412   CGDebugInfo(CodeGenModule &CGM);
 413   ~CGDebugInfo();
 414
 415   void finalize();
 416
 417   /// Remap a given path with the current debug prefix map
 418   std::string remapDIPath(StringRef) const;
 419
 420   /// Register VLA size expression debug node with the qualified type.
 421   void registerVLASizeExpression(QualType Ty, llvm::Metadata *SizeExpr) {
 422     SizeExprCache[Ty] = SizeExpr;
 423   }
 424
 425   /// Module debugging: Support for building PCMs.
 426   /// @{
 427   /// Set the main CU's DwoId field to \p Signature.
 428   void setDwoId(uint64_t Signature);
 429
 430   /// When generating debug information for a clang module or
 431   /// precompiled header, this module map will be used to determine
 432   /// the module of origin of each Decl.
 433   void setModuleMap(ModuleMap &MMap) { ClangModuleMap = &MMap; }
 434
 435   /// When generating debug information for a clang module or
 436   /// precompiled header, this module map will be used to determine
 437   /// the module of origin of each Decl.
 438   void setPCHDescriptor(ASTSourceDescriptor PCH) { PCHDescriptor = PCH; }
 439   /// @}
 440
 441   /// Update the current source location. If \arg loc is invalid it is
 442   /// ignored.
 443   void setLocation(SourceLocation Loc);
 444
 445   /// Return the current source location. This does not necessarily correspond
 446   /// to the IRBuilder's current DebugLoc.
 447   SourceLocation getLocation() const { return CurLoc; }
 448
 449   /// Update the current inline scope. All subsequent calls to \p EmitLocation
 450   /// will create a location with this inlinedAt field.
 451   void setInlinedAt(llvm::MDNode *InlinedAt) { CurInlinedAt = InlinedAt; }
 452
 453   /// \return the current inline scope.
 454   llvm::MDNode *getInlinedAt() const { return CurInlinedAt; }
 455
 456   // Converts a SourceLocation to a DebugLoc
 457   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Loc);
 458
 459   /// Emit metadata to indicate a change in line/column information in
 460   /// the source file. If the location is invalid, the previous
 461   /// location will be reused.
 462   void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc);
 463
 464   QualType getFunctionType(const FunctionDecl *FD, QualType RetTy,
 465                            const SmallVectorImpl<const VarDecl *> &Args);
 466
 467   /// Emit a call to llvm.dbg.function.start to indicate
 468   /// start of a new function.
 469   /// \param Loc       The location of the function header.
 470   /// \param ScopeLoc  The location of the function body.
 471   void emitFunctionStart(GlobalDecl GD, SourceLocation Loc,
 472                          SourceLocation ScopeLoc, QualType FnType,
 473                          llvm::Function *Fn, bool CurFnIsThunk);
 474
 475   /// Start a new scope for an inlined function.
 476   void EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD);
 477   /// End an inlined function scope.
 478   void EmitInlineFunctionEnd(CGBuilderTy &Builder);
 479
 480   /// Emit debug info for a function declaration.
 481   /// \p Fn is set only when a declaration for a debug call site gets created.
 482   void EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 483                         QualType FnType, llvm::Function *Fn = nullptr);
 484
 485   /// Emit debug info for an extern function being called.
 486   /// This is needed for call site debug info.
 487   void EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
 488                                QualType CalleeType,
 489                                const FunctionDecl *CalleeDecl);
 490
 491   /// Constructs the debug code for exiting a function.
 492   void EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn);
 493
 494   /// Emit metadata to indicate the beginning of a new lexical block
 495   /// and push the block onto the stack.
 496   void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);
 497
 498   /// Emit metadata to indicate the end of a new lexical block and pop
 499   /// the current block.
 500   void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);
 501
 502   /// Emit call to \c llvm.dbg.declare for an automatic variable
 503   /// declaration.
 504   /// Returns a pointer to the DILocalVariable associated with the
 505   /// llvm.dbg.declare, or nullptr otherwise.
 506   llvm::DILocalVariable *
 507   EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,
 508                             CGBuilderTy &Builder,
 509                             const bool UsePointerValue = false);
 510
 511   /// Emit call to \c llvm.dbg.label for an label.
 512   void EmitLabel(const LabelDecl *D, CGBuilderTy &Builder);
 513
 514   /// Emit call to \c llvm.dbg.declare for an imported variable
 515   /// declaration in a block.
 516   void EmitDeclareOfBlockDeclRefVariable(
 517       const VarDecl *variable, llvm::Value *storage, CGBuilderTy &Builder,
 518       const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint = nullptr);
 519
 520   /// Emit call to \c llvm.dbg.declare for an argument variable
 521   /// declaration.
 522   llvm::DILocalVariable *
 523   EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI, unsigned ArgNo,
 524                            CGBuilderTy &Builder, bool UsePointerValue = false);
 525
 526   /// Emit call to \c llvm.dbg.declare for the block-literal argument
 527   /// to a block invocation function.
 528   void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
 529                                             StringRef Name, unsigned ArgNo,
 530                                             llvm::AllocaInst *LocalAddr,
 531                                             CGBuilderTy &Builder);
 532
 533   /// Emit information about a global variable.
 534   void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
 535
 536   /// Emit a constant global variable's debug info.
 537   void EmitGlobalVariable(const ValueDecl *VD, const APValue &Init);
 538
 539   /// Emit information about an external variable.
 540   void EmitExternalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
 541
 542   /// Emit a pseudo variable and debug info for an intermediate value if it does
 543   /// not correspond to a variable in the source code, so that a profiler can
 544   /// track more accurate usage of certain instructions of interest.
 545   void EmitPseudoVariable(CGBuilderTy &Builder, llvm::Instruction *Value,
 546                           QualType Ty);
 547
 548   /// Emit information about global variable alias.
 549   void EmitGlobalAlias(const llvm::GlobalValue *GV, const GlobalDecl Decl);
 550
 551   /// Emit C++ using directive.
 552   void EmitUsingDirective(const UsingDirectiveDecl &UD);
 553
 554   /// Emit the type explicitly casted to.
 555   void EmitExplicitCastType(QualType Ty);
 556
 557   /// Emit the type even if it might not be used.
 558   void EmitAndRetainType(QualType Ty);
 559
 560   /// Emit a shadow decl brought in by a using or using-enum
 561   void EmitUsingShadowDecl(const UsingShadowDecl &USD);
 562
 563   /// Emit C++ using declaration.
 564   void EmitUsingDecl(const UsingDecl &UD);
 565
 566   /// Emit C++ using-enum declaration.
 567   void EmitUsingEnumDecl(const UsingEnumDecl &UD);
 568
 569   /// Emit an @import declaration.
 570   void EmitImportDecl(const ImportDecl &ID);
 571
 572   /// DebugInfo isn't attached to string literals by default. While certain
 573   /// aspects of debuginfo aren't useful for string literals (like a name), it's
 574   /// nice to be able to symbolize the line and column information. This is
 575   /// especially useful for sanitizers, as it allows symbolization of
 576   /// heap-buffer-overflows on constant strings.
 577   void AddStringLiteralDebugInfo(llvm::GlobalVariable *GV,
 578                                  const StringLiteral *S);
 579
 580   /// Emit C++ namespace alias.
 581   llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA);
 582
 583   /// Emit record type's standalone debug info.
 584   llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L);
 585
 586   /// Emit an Objective-C interface type standalone debug info.
 587   llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);
 588
 589   /// Emit standalone debug info for a type.
 590   llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);
 591
 592   /// Add heapallocsite metadata for MSAllocator calls.
 593   void addHeapAllocSiteMetadata(llvm::CallBase *CallSite, QualType AllocatedTy,
 594                                 SourceLocation Loc);
 595
 596   void completeType(const EnumDecl *ED);
 597   void completeType(const RecordDecl *RD);
 598   void completeRequiredType(const RecordDecl *RD);
 599   void completeClassData(const RecordDecl *RD);
 600   void completeClass(const RecordDecl *RD);
 601
 602   void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);
 603   void completeUnusedClass(const CXXRecordDecl &D);
 604
 605   /// Create debug info for a macro defined by a #define directive or a macro
 606   /// undefined by a #undef directive.
 607   llvm::DIMacro *CreateMacro(llvm::DIMacroFile *Parent, unsigned MType,
 608                              SourceLocation LineLoc, StringRef Name,
 609                              StringRef Value);
 610
 611   /// Create debug info for a file referenced by an #include directive.
 612   llvm::DIMacroFile *CreateTempMacroFile(llvm::DIMacroFile *Parent,
 613                                          SourceLocation LineLoc,
 614                                          SourceLocation FileLoc);
 615
 616   Param2DILocTy &getParamDbgMappings() { return ParamDbgMappings; }
 617   ParamDecl2StmtTy &getCoroutineParameterMappings() {
 618     return CoroutineParameterMappings;
 619   }
 620
 621   /// Create a debug location from `TrapLocation` that adds an artificial inline
 622   /// frame where the frame name is
 623   ///
 624   /// * `<Prefix>:<Category>:<FailureMsg>`
 625   ///
 626   /// `<Prefix>` is "__clang_trap_msg".
 627   ///
 628   /// This is used to store failure reasons for traps.
 629   llvm::DILocation *CreateTrapFailureMessageFor(llvm::DebugLoc TrapLocation,
 630                                                 StringRef Category,
 631                                                 StringRef FailureMsg);
 632
 633 private:
 634   /// Emit call to llvm.dbg.declare for a variable declaration.
 635   /// Returns a pointer to the DILocalVariable associated with the
 636   /// llvm.dbg.declare, or nullptr otherwise.
 637   llvm::DILocalVariable *EmitDeclare(const VarDecl *decl, llvm::Value *AI,
 638                                      std::optional<unsigned> ArgNo,
 639                                      CGBuilderTy &Builder,
 640                                      const bool UsePointerValue = false);
 641
 642   /// Emit call to llvm.dbg.declare for a binding declaration.
 643   /// Returns a pointer to the DILocalVariable associated with the
 644   /// llvm.dbg.declare, or nullptr otherwise.
 645   llvm::DILocalVariable *EmitDeclare(const BindingDecl *decl, llvm::Value *AI,
 646                                      std::optional<unsigned> ArgNo,
 647                                      CGBuilderTy &Builder,
 648                                      const bool UsePointerValue = false);
 649
 650   struct BlockByRefType {
 651     /// The wrapper struct used inside the __block_literal struct.
 652     llvm::DIType *BlockByRefWrapper;
 653     /// The type as it appears in the source code.
 654     llvm::DIType *WrappedType;
 655   };
 656
 657   bool HasReconstitutableArgs(ArrayRef<TemplateArgument> Args) const;
 658   std::string GetName(const Decl *, bool Qualified = false) const;
 659
 660   /// Build up structure info for the byref.  See \a BuildByRefType.
 661   BlockByRefType EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
 662                                               uint64_t *OffSet);
 663
 664   /// Get context info for the DeclContext of \p Decl.
 665   llvm::DIScope *getDeclContextDescriptor(const Decl *D);
 666   /// Get context info for a given DeclContext \p Decl.
 667   llvm::DIScope *getContextDescriptor(const Decl *Context,
 668                                       llvm::DIScope *Default);
 669
 670   llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl);
 671
 672   /// Create a forward decl for a RecordType in a given context.
 673   llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *,
 674                                                   llvm::DIScope *);
 675
 676   /// Return current directory name.
 677   StringRef getCurrentDirname();
 678
 679   /// Create new compile unit.
 680   void CreateCompileUnit();
 681
 682   /// Compute the file checksum debug info for input file ID.
 683   std::optional<llvm::DIFile::ChecksumKind>
 684   computeChecksum(FileID FID, SmallString<64> &Checksum) const;
 685
 686   /// Get the source of the given file ID.
 687   std::optional<StringRef> getSource(const SourceManager &SM, FileID FID);
 688
 689   /// Convenience function to get the file debug info descriptor for the input
 690   /// location.
 691   llvm::DIFile *getOrCreateFile(SourceLocation Loc);
 692
 693   /// Create a file debug info descriptor for a source file.
 694   llvm::DIFile *
 695   createFile(StringRef FileName,
 696              std::optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo,
 697              std::optional<StringRef> Source);
 698
 699   /// Get the type from the cache or create a new type if necessary.
 700   llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg);
 701
 702   /// Get a reference to a clang module.  If \p CreateSkeletonCU is true,
 703   /// this also creates a split dwarf skeleton compile unit.
 704   llvm::DIModule *getOrCreateModuleRef(ASTSourceDescriptor Mod,
 705                                        bool CreateSkeletonCU);
 706
 707   /// DebugTypeExtRefs: If \p D originated in a clang module, return it.
 708   llvm::DIModule *getParentModuleOrNull(const Decl *D);
 709
 710   /// Get the type from the cache or create a new partial type if
 711   /// necessary.
 712   llvm::DICompositeType *getOrCreateLimitedType(const RecordType *Ty);
 713
 714   /// Create type metadata for a source language type.
 715   llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg);
 716
 717   /// Create new member and increase Offset by FType's size.
 718   llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType,
 719                                  StringRef Name, uint64_t *Offset);
 720
 721   /// Retrieve the DIDescriptor, if any, for the canonical form of this
 722   /// declaration.
 723   llvm::DINode *getDeclarationOrDefinition(const Decl *D);
 724
 725   /// \return debug info descriptor to describe method
 726   /// declaration for the given method definition.
 727   llvm::DISubprogram *getFunctionDeclaration(const Decl *D);
 728
 729   /// \return          debug info descriptor to the describe method declaration
 730   ///                  for the given method definition.
 731   /// \param FnType    For Objective-C methods, their type.
 732   /// \param LineNo    The declaration's line number.
 733   /// \param Flags     The DIFlags for the method declaration.
 734   /// \param SPFlags   The subprogram-spcific flags for the method declaration.
 735   llvm::DISubprogram *
 736   getObjCMethodDeclaration(const Decl *D, llvm::DISubroutineType *FnType,
 737                            unsigned LineNo, llvm::DINode::DIFlags Flags,
 738                            llvm::DISubprogram::DISPFlags SPFlags);
 739
 740   /// \return debug info descriptor to describe in-class static data
 741   /// member declaration for the given out-of-class definition.  If D
 742   /// is an out-of-class definition of a static data member of a
 743   /// class, find its corresponding in-class declaration.
 744   llvm::DIDerivedType *
 745   getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);
 746
 747   /// Helper that either creates a forward declaration or a stub.
 748   llvm::DISubprogram *getFunctionFwdDeclOrStub(GlobalDecl GD, bool Stub);
 749
 750   /// Create a subprogram describing the forward declaration
 751   /// represented in the given FunctionDecl wrapped in a GlobalDecl.
 752   llvm::DISubprogram *getFunctionForwardDeclaration(GlobalDecl GD);
 753
 754   /// Create a DISubprogram describing the function
 755   /// represented in the given FunctionDecl wrapped in a GlobalDecl.
 756   llvm::DISubprogram *getFunctionStub(GlobalDecl GD);
 757
 758   /// Create a global variable describing the forward declaration
 759   /// represented in the given VarDecl.
 760   llvm::DIGlobalVariable *
 761   getGlobalVariableForwardDeclaration(const VarDecl *VD);
 762
 763   /// Return a global variable that represents one of the collection of global
 764   /// variables created for an anonmyous union.
 765   ///
 766   /// Recursively collect all of the member fields of a global
 767   /// anonymous decl and create static variables for them. The first
 768   /// time this is called it needs to be on a union and then from
 769   /// there we can have additional unnamed fields.
 770   llvm::DIGlobalVariableExpression *
 771   CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit,
 772                          unsigned LineNo, StringRef LinkageName,
 773                          llvm::GlobalVariable *Var, llvm::DIScope *DContext);
 774
 775
 776   /// Return flags which enable debug info emission for call sites, provided
 777   /// that it is supported and enabled.
 778   llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;
 779
 780   /// Get the printing policy for producing names for debug info.
 781   PrintingPolicy getPrintingPolicy() const;
 782
 783   /// Get function name for the given FunctionDecl. If the name is
 784   /// constructed on demand (e.g., C++ destructor) then the name is
 785   /// stored on the side.
 786   StringRef getFunctionName(const FunctionDecl *FD);
 787
 788   /// Returns the unmangled name of an Objective-C method.
 789   /// This is the display name for the debugging info.
 790   StringRef getObjCMethodName(const ObjCMethodDecl *FD);
 791
 792   /// Return selector name. This is used for debugging
 793   /// info.
 794   StringRef getSelectorName(Selector S);
 795
 796   /// Get class name including template argument list.
 797   StringRef getClassName(const RecordDecl *RD);
 798
 799   /// Get the vtable name for the given class.
 800   StringRef getVTableName(const CXXRecordDecl *Decl);
 801
 802   /// Get the name to use in the debug info for a dynamic initializer or atexit
 803   /// stub function.
 804   StringRef getDynamicInitializerName(const VarDecl *VD,
 805                                       DynamicInitKind StubKind,
 806                                       llvm::Function *InitFn);
 807
 808   /// Get line number for the location. If location is invalid
 809   /// then use current location.
 810   unsigned getLineNumber(SourceLocation Loc);
 811
 812   /// Get column number for the location. If location is
 813   /// invalid then use current location.
 814   /// \param Force  Assume DebugColumnInfo option is true.
 815   unsigned getColumnNumber(SourceLocation Loc, bool Force = false);
 816
 817   /// Collect various properties of a FunctionDecl.
 818   /// \param GD  A GlobalDecl whose getDecl() must return a FunctionDecl.
 819   void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
 820                                 StringRef &Name, StringRef &LinkageName,
 821                                 llvm::DIScope *&FDContext,
 822                                 llvm::DINodeArray &TParamsArray,
 823                                 llvm::DINode::DIFlags &Flags);
 824
 825   /// Collect various properties of a VarDecl.
 826   void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
 827                            unsigned &LineNo, QualType &T, StringRef &Name,
 828                            StringRef &LinkageName,
 829                            llvm::MDTuple *&TemplateParameters,
 830                            llvm::DIScope *&VDContext);
 831
 832   /// Create a DIExpression representing the constant corresponding
 833   /// to the specified 'Val'. Returns nullptr on failure.
 834   llvm::DIExpression *createConstantValueExpression(const clang::ValueDecl *VD,
 835                                                     const APValue &Val);
 836
 837   /// Allocate a copy of \p A using the DebugInfoNames allocator
 838   /// and return a reference to it. If multiple arguments are given the strings
 839   /// are concatenated.
 840   StringRef internString(StringRef A, StringRef B = StringRef()) {
 841     char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());
 842     if (!A.empty())
 843       std::memcpy(Data, A.data(), A.size());
 844     if (!B.empty())
 845       std::memcpy(Data + A.size(), B.data(), B.size());
 846     return StringRef(Data, A.size() + B.size());
 847   }
 848 };
 849
 850 /// A scoped helper to set the current debug location to the specified
 851 /// location or preferred location of the specified Expr.
 852 class ApplyDebugLocation {
 853 private:
 854   void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false);
 855   ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty,
 856                      SourceLocation TemporaryLocation);
 857
 858   llvm::DebugLoc OriginalLocation;
 859   CodeGenFunction *CGF;
 860
 861 public:
 862   /// Set the location to the (valid) TemporaryLocation.
 863   ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);
 864   ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);
 865   ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);
 866   ApplyDebugLocation(ApplyDebugLocation &&Other) : CGF(Other.CGF) {
 867     Other.CGF = nullptr;
 868   }
 869
 870   // Define copy assignment operator.
 871   ApplyDebugLocation &operator=(ApplyDebugLocation &&Other) {
 872     if (this != &Other) {
 873       CGF = Other.CGF;
 874       Other.CGF = nullptr;
 875     }
 876     return *this;
 877   }
 878
 879   ~ApplyDebugLocation();
 880
 881   /// Apply TemporaryLocation if it is valid. Otherwise switch
 882   /// to an artificial debug location that has a valid scope, but no
 883   /// line information.
 884   ///
 885   /// Artificial locations are useful when emitting compiler-generated
 886   /// helper functions that have no source location associated with
 887   /// them. The DWARF specification allows the compiler to use the
 888   /// special line number 0 to indicate code that can not be
 889   /// attributed to any source location. Note that passing an empty
 890   /// SourceLocation to CGDebugInfo::setLocation() will result in the
 891   /// last valid location being reused.
 892   static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) {
 893     return ApplyDebugLocation(CGF, false, SourceLocation());
 894   }
 895   /// Apply TemporaryLocation if it is valid. Otherwise switch
 896   /// to an artificial debug location that has a valid scope, but no
 897   /// line information.
 898   static ApplyDebugLocation
 899   CreateDefaultArtificial(CodeGenFunction &CGF,
 900                           SourceLocation TemporaryLocation) {
 901     return ApplyDebugLocation(CGF, false, TemporaryLocation);
 902   }
 903
 904   /// Set the IRBuilder to not attach debug locations.  Note that
 905   /// passing an empty SourceLocation to \a CGDebugInfo::setLocation()
 906   /// will result in the last valid location being reused.  Note that
 907   /// all instructions that do not have a location at the beginning of
 908   /// a function are counted towards to function prologue.
 909   static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) {
 910     return ApplyDebugLocation(CGF, true, SourceLocation());
 911   }
 912 };
 913
 914 /// A scoped helper to set the current debug location to an inlined location.
 915 class ApplyInlineDebugLocation {
 916   SourceLocation SavedLocation;
 917   CodeGenFunction *CGF;
 918
 919 public:
 920   /// Set up the CodeGenFunction's DebugInfo to produce inline locations for the
 921   /// function \p InlinedFn. The current debug location becomes the inlined call
 922   /// site of the inlined function.
 923   ApplyInlineDebugLocation(CodeGenFunction &CGF, GlobalDecl InlinedFn);
 924   /// Restore everything back to the original state.
 925   ~ApplyInlineDebugLocation();
 926 };
 927
 928 } // namespace CodeGen
 929 } // namespace clang
 930
 931 #endif // LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H