//===--- CGDebugInfo.h - DebugInfo for LLVM CodeGen -------------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

// This is the source-level debug info generator for llvm translation.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H

#define LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H

#include "CGBuilder.h"

#include "clang/AST/DeclCXX.h"

#include "clang/AST/Expr.h"

#include "clang/AST/ExternalASTSource.h"

#include "clang/AST/PrettyPrinter.h"

#include "clang/AST/Type.h"

#include "clang/AST/TypeOrdering.h"

#include "clang/Basic/CodeGenOptions.h"

#include "clang/Basic/Module.h"

#include "clang/Basic/SourceLocation.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/DenseSet.h"

#include "llvm/IR/DIBuilder.h"

#include "llvm/IR/DebugInfo.h"

#include "llvm/IR/ValueHandle.h"

#include "llvm/Support/Allocator.h"

#include <optional>

namespace llvm {

class MDNode;

}

namespace clang {

class ClassTemplateSpecializationDecl;

class GlobalDecl;

class ModuleMap;

class ObjCInterfaceDecl;

class UsingDecl;

class VarDecl;

enum class DynamicInitKind : unsigned;

namespace CodeGen {

class CodeGenModule;

class CodeGenFunction;

class CGBlockInfo;

/// This class gathers all debug information during compilation and is

/// responsible for emitting to llvm globals or pass directly to the

/// backend.

class CGDebugInfo {

  friend class ApplyDebugLocation;

  friend class SaveAndRestoreLocation;

  CodeGenModule &CGM;

  const llvm::codegenoptions::DebugInfoKind DebugKind;

  bool DebugTypeExtRefs;

  llvm::DIBuilder DBuilder;

  llvm::DICompileUnit *TheCU = nullptr;

  ModuleMap *ClangModuleMap = nullptr;

  ASTSourceDescriptor PCHDescriptor;

  SourceLocation CurLoc;

  llvm::MDNode *CurInlinedAt = nullptr;

  llvm::DIType *VTablePtrType = nullptr;

  llvm::DIType *ClassTy = nullptr;

  llvm::DICompositeType *ObjTy = nullptr;

  llvm::DIType *SelTy = nullptr;

#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \

  llvm::DIType *SingletonId = nullptr;

#include "clang/Basic/OpenCLImageTypes.def"

  llvm::DIType *OCLSamplerDITy = nullptr;

  llvm::DIType *OCLEventDITy = nullptr;

  llvm::DIType *OCLClkEventDITy = nullptr;

  llvm::DIType *OCLQueueDITy = nullptr;

  llvm::DIType *OCLNDRangeDITy = nullptr;

  llvm::DIType *OCLReserveIDDITy = nullptr;

#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \

  llvm::DIType *Id##Ty = nullptr;

#include "clang/Basic/OpenCLExtensionTypes.def"

#define WASM_TYPE(Name, Id, SingletonId) llvm::DIType *SingletonId = nullptr;

#include "clang/Basic/WebAssemblyReferenceTypes.def"

  /// Cache of previously constructed Types.

  llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache;

  /// Cache that maps VLA types to size expressions for that type,

  /// represented by instantiated Metadata nodes.

  llvm::SmallDenseMap<QualType, llvm::Metadata *> SizeExprCache;

  /// Callbacks to use when printing names and types.

  class PrintingCallbacks final : public clang::PrintingCallbacks {

    const CGDebugInfo &Self;

  public:

    PrintingCallbacks(const CGDebugInfo &Self) : Self(Self) {}

    std::string remapPath(StringRef Path) const override {

      return Self.remapDIPath(Path);

    }

  };

  PrintingCallbacks PrintCB = {*this};

  struct ObjCInterfaceCacheEntry {

    const ObjCInterfaceType *Type;

    llvm::DIType *Decl;

    llvm::DIFile *Unit;

    ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl,

                            llvm::DIFile *Unit)

        : Type(Type), Decl(Decl), Unit(Unit) {}

  };

  /// Cache of previously constructed interfaces which may change.

  llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;

  /// Cache of forward declarations for methods belonging to the interface.

  /// The extra bit on the DISubprogram specifies whether a method is

  /// "objc_direct".

  llvm::DenseMap<const ObjCInterfaceDecl *,

                 std::vector<llvm::PointerIntPair<llvm::DISubprogram *, 1>>>

      ObjCMethodCache;

  /// Cache of references to clang modules and precompiled headers.

  llvm::DenseMap<const Module *, llvm::TrackingMDRef> ModuleCache;

  /// List of interfaces we want to keep even if orphaned.

  std::vector<void *> RetainedTypes;

  /// Cache of forward declared types to RAUW at the end of compilation.

  std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap;

  /// Cache of replaceable forward declarations (functions and

  /// variables) to RAUW at the end of compilation.

  std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>>

      FwdDeclReplaceMap;

  /// Keep track of our current nested lexical block.

  std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;

  llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;

  /// Keep track of LexicalBlockStack counter at the beginning of a

  /// function. This is used to pop unbalanced regions at the end of a

  /// function.

  std::vector<unsigned> FnBeginRegionCount;

  /// This is a storage for names that are constructed on demand. For

  /// example, C++ destructors, C++ operators etc..

  llvm::BumpPtrAllocator DebugInfoNames;

  StringRef CWDName;

  llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;

  llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;

  /// Cache declarations relevant to DW_TAG_imported_declarations (C++

  /// using declarations and global alias variables) that aren't covered

  /// by other more specific caches.

  llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache;

  llvm::DenseMap<const Decl *, llvm::TrackingMDRef> ImportedDeclCache;

  llvm::DenseMap<const NamespaceDecl *, llvm::TrackingMDRef> NamespaceCache;

  llvm::DenseMap<const NamespaceAliasDecl *, llvm::TrackingMDRef>

      NamespaceAliasCache;

  llvm::DenseMap<const Decl *, llvm::TypedTrackingMDRef<llvm::DIDerivedType>>

      StaticDataMemberCache;

  using ParamDecl2StmtTy = llvm::DenseMap<const ParmVarDecl *, const Stmt *>;

  using Param2DILocTy =

      llvm::DenseMap<const ParmVarDecl *, llvm::DILocalVariable *>;

  /// The key is coroutine real parameters, value is coroutine move parameters.

  ParamDecl2StmtTy CoroutineParameterMappings;

  /// The key is coroutine real parameters, value is DIVariable in LLVM IR.

  Param2DILocTy ParamDbgMappings;

  /// Helper functions for getOrCreateType.

  /// @{

  /// Currently the checksum of an interface includes the number of

  /// ivars and property accessors.

  llvm::DIType *CreateType(const BuiltinType *Ty);

  llvm::DIType *CreateType(const ComplexType *Ty);

  llvm::DIType *CreateType(const BitIntType *Ty);

  llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg);

  llvm::DIType *CreateQualifiedType(const FunctionProtoType *Ty,

                                    llvm::DIFile *Fg);

  llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg);

  llvm::DIType *CreateType(const TemplateSpecializationType *Ty,

                           llvm::DIFile *Fg);

  llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F);

  /// Get structure or union type.

  llvm::DIType *CreateType(const RecordType *Tyg);

  /// Create definition for the specified 'Ty'.

  ///

  /// \returns A pair of 'llvm::DIType's. The first is the definition

  /// of the 'Ty'. The second is the type specified by the preferred_name

  /// attribute on 'Ty', which can be a nullptr if no such attribute

  /// exists.

  std::pair<llvm::DIType *, llvm::DIType *>

  CreateTypeDefinition(const RecordType *Ty);

  llvm::DICompositeType *CreateLimitedType(const RecordType *Ty);

  void CollectContainingType(const CXXRecordDecl *RD,

                             llvm::DICompositeType *CT);

  /// Get Objective-C interface type.

  llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty,

                                     llvm::DIFile *F);

  /// Get Objective-C object type.

  llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const ObjCTypeParamType *Ty, llvm::DIFile *Unit);

  llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const ConstantMatrixType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit);

  llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F);

  llvm::DIType *CreateType(const PipeType *Ty, llvm::DIFile *F);

  /// Get enumeration type.

  llvm::DIType *CreateEnumType(const EnumType *Ty);

  llvm::DIType *CreateTypeDefinition(const EnumType *Ty);

  /// Look up the completed type for a self pointer in the TypeCache and

  /// create a copy of it with the ObjectPointer and Artificial flags

  /// set. If the type is not cached, a new one is created. This should

  /// never happen though, since creating a type for the implicit self

  /// argument implies that we already parsed the interface definition

  /// and the ivar declarations in the implementation.

  llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty);

  /// @}

  /// Get the type from the cache or return null type if it doesn't

  /// exist.

  llvm::DIType *getTypeOrNull(const QualType);

  /// Return the debug type for a C++ method.

  /// \arg CXXMethodDecl is of FunctionType. This function type is

  /// not updated to include implicit \c this pointer. Use this routine

  /// to get a method type which includes \c this pointer.

  llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method,

                                                llvm::DIFile *F);

  llvm::DISubroutineType *

  getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func,

                                llvm::DIFile *Unit);

  llvm::DISubroutineType *

  getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F);

  /// \return debug info descriptor for vtable.

  llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F);

  /// \return namespace descriptor for the given namespace decl.

  llvm::DINamespace *getOrCreateNamespace(const NamespaceDecl *N);

  llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty,

                                      QualType PointeeTy, llvm::DIFile *F);

  llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache);

  /// A helper function to create a subprogram for a single member

  /// function GlobalDecl.

  llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method,

                                              llvm::DIFile *F,

                                              llvm::DIType *RecordTy);

  /// A helper function to collect debug info for C++ member

  /// functions. This is used while creating debug info entry for a

  /// Record.

  void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F,

                                 SmallVectorImpl<llvm::Metadata *> &E,

                                 llvm::DIType *T);

  /// A helper function to collect debug info for C++ base

  /// classes. This is used while creating debug info entry for a

  /// Record.

  void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F,

                       SmallVectorImpl<llvm::Metadata *> &EltTys,

                       llvm::DIType *RecordTy);

  /// Helper function for CollectCXXBases.

  /// Adds debug info entries for types in Bases that are not in SeenTypes.

  void CollectCXXBasesAux(

      const CXXRecordDecl *RD, llvm::DIFile *Unit,

      SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy,

      const CXXRecordDecl::base_class_const_range &Bases,

      llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> &SeenTypes,

      llvm::DINode::DIFlags StartingFlags);

  /// Helper function that returns the llvm::DIType that the

  /// PreferredNameAttr attribute on \ref RD refers to. If no such

  /// attribute exists, returns nullptr.

  llvm::DIType *GetPreferredNameType(const CXXRecordDecl *RD,

                                     llvm::DIFile *Unit);

  struct TemplateArgs {

    const TemplateParameterList *TList;

    llvm::ArrayRef<TemplateArgument> Args;

  };

  /// A helper function to collect template parameters.

  llvm::DINodeArray CollectTemplateParams(std::optional<TemplateArgs> Args,

                                          llvm::DIFile *Unit);

  /// A helper function to collect debug info for function template

  /// parameters.

  llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD,

                                                  llvm::DIFile *Unit);

  /// A helper function to collect debug info for function template

  /// parameters.

  llvm::DINodeArray CollectVarTemplateParams(const VarDecl *VD,

                                             llvm::DIFile *Unit);

  std::optional<TemplateArgs> GetTemplateArgs(const VarDecl *) const;

  std::optional<TemplateArgs> GetTemplateArgs(const RecordDecl *) const;

  std::optional<TemplateArgs> GetTemplateArgs(const FunctionDecl *) const;

  /// A helper function to collect debug info for template

  /// parameters.

  llvm::DINodeArray CollectCXXTemplateParams(const RecordDecl *TS,

                                             llvm::DIFile *F);

  /// A helper function to collect debug info for btf_decl_tag annotations.

  llvm::DINodeArray CollectBTFDeclTagAnnotations(const Decl *D);

  llvm::DIType *createFieldType(StringRef name, QualType type,

                                SourceLocation loc, AccessSpecifier AS,

                                uint64_t offsetInBits, uint32_t AlignInBits,

                                llvm::DIFile *tunit, llvm::DIScope *scope,

                                const RecordDecl *RD = nullptr,

                                llvm::DINodeArray Annotations = nullptr);

  llvm::DIType *createFieldType(StringRef name, QualType type,

                                SourceLocation loc, AccessSpecifier AS,

                                uint64_t offsetInBits, llvm::DIFile *tunit,

                                llvm::DIScope *scope,

                                const RecordDecl *RD = nullptr) {

    return createFieldType(name, type, loc, AS, offsetInBits, 0, tunit, scope,

                           RD);

  }

  /// Create new bit field member.

  llvm::DIDerivedType *createBitFieldType(const FieldDecl *BitFieldDecl,

                                          llvm::DIScope *RecordTy,

                                          const RecordDecl *RD);

  /// Create an anonnymous zero-size separator for bit-field-decl if needed on

  /// the target.

  llvm::DIDerivedType *createBitFieldSeparatorIfNeeded(

      const FieldDecl *BitFieldDecl, const llvm::DIDerivedType *BitFieldDI,

      llvm::ArrayRef<llvm::Metadata *> PreviousFieldsDI, const RecordDecl *RD);

  /// Helpers for collecting fields of a record.

  /// @{

  void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,

                                 SmallVectorImpl<llvm::Metadata *> &E,

                                 llvm::DIType *RecordTy);

  llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var,

                                               llvm::DIType *RecordTy,

                                               const RecordDecl *RD);

  void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,

                                llvm::DIFile *F,

                                SmallVectorImpl<llvm::Metadata *> &E,

                                llvm::DIType *RecordTy, const RecordDecl *RD);

  void CollectRecordNestedType(const TypeDecl *RD,

                               SmallVectorImpl<llvm::Metadata *> &E);

  void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F,

                           SmallVectorImpl<llvm::Metadata *> &E,

                           llvm::DICompositeType *RecordTy);

  /// If the C++ class has vtable info then insert appropriate debug

  /// info entry in EltTys vector.

  void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F,

                         SmallVectorImpl<llvm::Metadata *> &EltTys);

  /// @}

  /// Create a new lexical block node and push it on the stack.

  void CreateLexicalBlock(SourceLocation Loc);

  /// If target-specific LLVM \p AddressSpace directly maps to target-specific

  /// DWARF address space, appends extended dereferencing mechanism to complex

  /// expression \p Expr. Otherwise, does nothing.

  ///

  /// Extended dereferencing mechanism is has the following format:

  ///     DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef

  void AppendAddressSpaceXDeref(unsigned AddressSpace,

                                SmallVectorImpl<uint64_t> &Expr) const;

  /// A helper function to collect debug info for the default elements of a

  /// block.

  ///

  /// \returns The next available field offset after the default elements.

  uint64_t collectDefaultElementTypesForBlockPointer(

      const BlockPointerType *Ty, llvm::DIFile *Unit,

      llvm::DIDerivedType *DescTy, unsigned LineNo,

      SmallVectorImpl<llvm::Metadata *> &EltTys);

  /// A helper function to collect debug info for the default fields of a

  /// block.

  void collectDefaultFieldsForBlockLiteralDeclare(

      const CGBlockInfo &Block, const ASTContext &Context, SourceLocation Loc,

      const llvm::StructLayout &BlockLayout, llvm::DIFile *Unit,

      SmallVectorImpl<llvm::Metadata *> &Fields);

public:

  CGDebugInfo(CodeGenModule &CGM);

  ~CGDebugInfo();

  void finalize();

  /// Remap a given path with the current debug prefix map

  std::string remapDIPath(StringRef) const;

  /// Register VLA size expression debug node with the qualified type.

  void registerVLASizeExpression(QualType Ty, llvm::Metadata *SizeExpr) {

    SizeExprCache[Ty] = SizeExpr;

  }

  /// Module debugging: Support for building PCMs.

  /// @{

  /// Set the main CU's DwoId field to \p Signature.

  void setDwoId(uint64_t Signature);

  /// When generating debug information for a clang module or

  /// precompiled header, this module map will be used to determine

  /// the module of origin of each Decl.

  void setModuleMap(ModuleMap &MMap) { ClangModuleMap = &MMap; }

  /// When generating debug information for a clang module or

  /// precompiled header, this module map will be used to determine

  /// the module of origin of each Decl.

  void setPCHDescriptor(ASTSourceDescriptor PCH) { PCHDescriptor = PCH; }

  /// @}

  /// Update the current source location. If \arg loc is invalid it is

  /// ignored.

  void setLocation(SourceLocation Loc);

  /// Return the current source location. This does not necessarily correspond

  /// to the IRBuilder's current DebugLoc.

  SourceLocation getLocation() const { return CurLoc; }

  /// Update the current inline scope. All subsequent calls to \p EmitLocation

  /// will create a location with this inlinedAt field.

  void setInlinedAt(llvm::MDNode *InlinedAt) { CurInlinedAt = InlinedAt; }

  /// \return the current inline scope.

  llvm::MDNode *getInlinedAt() const { return CurInlinedAt; }

  // Converts a SourceLocation to a DebugLoc

  llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Loc);

  /// Emit metadata to indicate a change in line/column information in

  /// the source file. If the location is invalid, the previous

  /// location will be reused.

  void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc);

  QualType getFunctionType(const FunctionDecl *FD, QualType RetTy,

                           const SmallVectorImpl<const VarDecl *> &Args);

  /// Emit a call to llvm.dbg.function.start to indicate

  /// start of a new function.

  /// \param Loc       The location of the function header.

  /// \param ScopeLoc  The location of the function body.

  void emitFunctionStart(GlobalDecl GD, SourceLocation Loc,

                         SourceLocation ScopeLoc, QualType FnType,

                         llvm::Function *Fn, bool CurFnIsThunk);

  /// Start a new scope for an inlined function.

  void EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD);

  /// End an inlined function scope.

  void EmitInlineFunctionEnd(CGBuilderTy &Builder);

  /// Emit debug info for a function declaration.

  /// \p Fn is set only when a declaration for a debug call site gets created.

  void EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,

                        QualType FnType, llvm::Function *Fn = nullptr);

  /// Emit debug info for an extern function being called.

  /// This is needed for call site debug info.

  void EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,

                               QualType CalleeType,

                               const FunctionDecl *CalleeDecl);

  /// Constructs the debug code for exiting a function.

  void EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn);

  /// Emit metadata to indicate the beginning of a new lexical block

  /// and push the block onto the stack.

  void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);

  /// Emit metadata to indicate the end of a new lexical block and pop

  /// the current block.

  void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);

  /// Emit call to \c llvm.dbg.declare for an automatic variable

  /// declaration.

  /// Returns a pointer to the DILocalVariable associated with the

  /// llvm.dbg.declare, or nullptr otherwise.

  llvm::DILocalVariable *

  EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,

                            CGBuilderTy &Builder,

                            const bool UsePointerValue = false);

  /// Emit call to \c llvm.dbg.label for an label.

  void EmitLabel(const LabelDecl *D, CGBuilderTy &Builder);

  /// Emit call to \c llvm.dbg.declare for an imported variable

  /// declaration in a block.

  void EmitDeclareOfBlockDeclRefVariable(

      const VarDecl *variable, llvm::Value *storage, CGBuilderTy &Builder,

      const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint = nullptr);

  /// Emit call to \c llvm.dbg.declare for an argument variable

  /// declaration.

  llvm::DILocalVariable *

  EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI, unsigned ArgNo,

                           CGBuilderTy &Builder, bool UsePointerValue = false);

  /// Emit call to \c llvm.dbg.declare for the block-literal argument

  /// to a block invocation function.

  void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,

                                            StringRef Name, unsigned ArgNo,

                                            llvm::AllocaInst *LocalAddr,

                                            CGBuilderTy &Builder);

  /// Emit information about a global variable.

  void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);

  /// Emit a constant global variable's debug info.

  void EmitGlobalVariable(const ValueDecl *VD, const APValue &Init);

  /// Emit information about an external variable.

  void EmitExternalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);

  /// Emit information about global variable alias.

  void EmitGlobalAlias(const llvm::GlobalValue *GV, const GlobalDecl Decl);

  /// Emit C++ using directive.

  void EmitUsingDirective(const UsingDirectiveDecl &UD);

  /// Emit the type explicitly casted to.

  void EmitExplicitCastType(QualType Ty);

  /// Emit the type even if it might not be used.

  void EmitAndRetainType(QualType Ty);

  /// Emit a shadow decl brought in by a using or using-enum

  void EmitUsingShadowDecl(const UsingShadowDecl &USD);

  /// Emit C++ using declaration.

  void EmitUsingDecl(const UsingDecl &UD);

  /// Emit C++ using-enum declaration.

  void EmitUsingEnumDecl(const UsingEnumDecl &UD);

  /// Emit an @import declaration.

  void EmitImportDecl(const ImportDecl &ID);

  /// DebugInfo isn't attached to string literals by default. While certain

  /// aspects of debuginfo aren't useful for string literals (like a name), it's

  /// nice to be able to symbolize the line and column information. This is

  /// especially useful for sanitizers, as it allows symbolization of

  /// heap-buffer-overflows on constant strings.

  void AddStringLiteralDebugInfo(llvm::GlobalVariable *GV,

                                 const StringLiteral *S);

  /// Emit C++ namespace alias.

  llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA);

  /// Emit record type's standalone debug info.

  llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L);

  /// Emit an Objective-C interface type standalone debug info.

  llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);

  /// Emit standalone debug info for a type.

  llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);

  /// Add heapallocsite metadata for MSAllocator calls.

  void addHeapAllocSiteMetadata(llvm::CallBase *CallSite, QualType AllocatedTy,

                                SourceLocation Loc);

  void completeType(const EnumDecl *ED);

  void completeType(const RecordDecl *RD);

  void completeRequiredType(const RecordDecl *RD);

  void completeClassData(const RecordDecl *RD);

  void completeClass(const RecordDecl *RD);

  void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);

  void completeUnusedClass(const CXXRecordDecl &D);

  /// Create debug info for a macro defined by a #define directive or a macro

  /// undefined by a #undef directive.

  llvm::DIMacro *CreateMacro(llvm::DIMacroFile *Parent, unsigned MType,

                             SourceLocation LineLoc, StringRef Name,

                             StringRef Value);

  /// Create debug info for a file referenced by an #include directive.

  llvm::DIMacroFile *CreateTempMacroFile(llvm::DIMacroFile *Parent,

                                         SourceLocation LineLoc,

                                         SourceLocation FileLoc);

  Param2DILocTy &getParamDbgMappings() { return ParamDbgMappings; }

  ParamDecl2StmtTy &getCoroutineParameterMappings() {

    return CoroutineParameterMappings;

  }

private:

  /// Emit call to llvm.dbg.declare for a variable declaration.

  /// Returns a pointer to the DILocalVariable associated with the

  /// llvm.dbg.declare, or nullptr otherwise.

  llvm::DILocalVariable *EmitDeclare(const VarDecl *decl, llvm::Value *AI,

                                     std::optional<unsigned> ArgNo,

                                     CGBuilderTy &Builder,

                                     const bool UsePointerValue = false);

  /// Emit call to llvm.dbg.declare for a binding declaration.

  /// Returns a pointer to the DILocalVariable associated with the

  /// llvm.dbg.declare, or nullptr otherwise.

  llvm::DILocalVariable *EmitDeclare(const BindingDecl *decl, llvm::Value *AI,

                                     std::optional<unsigned> ArgNo,

                                     CGBuilderTy &Builder,

                                     const bool UsePointerValue = false);

  struct BlockByRefType {

    /// The wrapper struct used inside the __block_literal struct.

    llvm::DIType *BlockByRefWrapper;

    /// The type as it appears in the source code.

    llvm::DIType *WrappedType;

  };

  std::string GetName(const Decl*, bool Qualified = false) const;

  /// Build up structure info for the byref.  See \a BuildByRefType.

  BlockByRefType EmitTypeForVarWithBlocksAttr(const VarDecl *VD,

                                              uint64_t *OffSet);

  /// Get context info for the DeclContext of \p Decl.

  llvm::DIScope *getDeclContextDescriptor(const Decl *D);

  /// Get context info for a given DeclContext \p Decl.

  llvm::DIScope *getContextDescriptor(const Decl *Context,

                                      llvm::DIScope *Default);

  llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl);

  /// Create a forward decl for a RecordType in a given context.

  llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *,

                                                  llvm::DIScope *);

  /// Return current directory name.

  StringRef getCurrentDirname();

  /// Create new compile unit.

  void CreateCompileUnit();

  /// Compute the file checksum debug info for input file ID.

  std::optional<llvm::DIFile::ChecksumKind>

  computeChecksum(FileID FID, SmallString<64> &Checksum) const;

  /// Get the source of the given file ID.

  std::optional<StringRef> getSource(const SourceManager &SM, FileID FID);

  /// Convenience function to get the file debug info descriptor for the input

  /// location.

  llvm::DIFile *getOrCreateFile(SourceLocation Loc);

  /// Create a file debug info descriptor for a source file.

  llvm::DIFile *

  createFile(StringRef FileName,

             std::optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo,

             std::optional<StringRef> Source);

  /// Get the type from the cache or create a new type if necessary.

  llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg);

  /// Get a reference to a clang module.  If \p CreateSkeletonCU is true,

  /// this also creates a split dwarf skeleton compile unit.

  llvm::DIModule *getOrCreateModuleRef(ASTSourceDescriptor Mod,

                                       bool CreateSkeletonCU);

  /// DebugTypeExtRefs: If \p D originated in a clang module, return it.

  llvm::DIModule *getParentModuleOrNull(const Decl *D);

  /// Get the type from the cache or create a new partial type if

  /// necessary.

  llvm::DICompositeType *getOrCreateLimitedType(const RecordType *Ty);

  /// Create type metadata for a source language type.

  llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg);

  /// Create new member and increase Offset by FType's size.

  llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType,

                                 StringRef Name, uint64_t *Offset);

  /// Retrieve the DIDescriptor, if any, for the canonical form of this

  /// declaration.

  llvm::DINode *getDeclarationOrDefinition(const Decl *D);

  /// \return debug info descriptor to describe method

  /// declaration for the given method definition.

  llvm::DISubprogram *getFunctionDeclaration(const Decl *D);

  /// \return          debug info descriptor to the describe method declaration

  ///                  for the given method definition.

  /// \param FnType    For Objective-C methods, their type.

  /// \param LineNo    The declaration's line number.

  /// \param Flags     The DIFlags for the method declaration.

  /// \param SPFlags   The subprogram-spcific flags for the method declaration.

  llvm::DISubprogram *

  getObjCMethodDeclaration(const Decl *D, llvm::DISubroutineType *FnType,

                           unsigned LineNo, llvm::DINode::DIFlags Flags,

                           llvm::DISubprogram::DISPFlags SPFlags);

  /// \return debug info descriptor to describe in-class static data

  /// member declaration for the given out-of-class definition.  If D

  /// is an out-of-class definition of a static data member of a

  /// class, find its corresponding in-class declaration.

  llvm::DIDerivedType *

  getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);

  /// Helper that either creates a forward declaration or a stub.

  llvm::DISubprogram *getFunctionFwdDeclOrStub(GlobalDecl GD, bool Stub);

  /// Create a subprogram describing the forward declaration

  /// represented in the given FunctionDecl wrapped in a GlobalDecl.

  llvm::DISubprogram *getFunctionForwardDeclaration(GlobalDecl GD);

  /// Create a DISubprogram describing the function

  /// represented in the given FunctionDecl wrapped in a GlobalDecl.

  llvm::DISubprogram *getFunctionStub(GlobalDecl GD);

  /// Create a global variable describing the forward declaration

  /// represented in the given VarDecl.

  llvm::DIGlobalVariable *

  getGlobalVariableForwardDeclaration(const VarDecl *VD);

  /// Return a global variable that represents one of the collection of global

  /// variables created for an anonmyous union.

  ///

  /// Recursively collect all of the member fields of a global

  /// anonymous decl and create static variables for them. The first

  /// time this is called it needs to be on a union and then from

  /// there we can have additional unnamed fields.

  llvm::DIGlobalVariableExpression *

  CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit,

                         unsigned LineNo, StringRef LinkageName,

                         llvm::GlobalVariable *Var, llvm::DIScope *DContext);

  /// Return flags which enable debug info emission for call sites, provided

  /// that it is supported and enabled.

  llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;

  /// Get the printing policy for producing names for debug info.

  PrintingPolicy getPrintingPolicy() const;

  /// Get function name for the given FunctionDecl. If the name is

  /// constructed on demand (e.g., C++ destructor) then the name is

  /// stored on the side.

  StringRef getFunctionName(const FunctionDecl *FD);

  /// Returns the unmangled name of an Objective-C method.

  /// This is the display name for the debugging info.

  StringRef getObjCMethodName(const ObjCMethodDecl *FD);

  /// Return selector name. This is used for debugging

  /// info.

  StringRef getSelectorName(Selector S);

  /// Get class name including template argument list.

  StringRef getClassName(const RecordDecl *RD);

  /// Get the vtable name for the given class.

  StringRef getVTableName(const CXXRecordDecl *Decl);

  /// Get the name to use in the debug info for a dynamic initializer or atexit

  /// stub function.

  StringRef getDynamicInitializerName(const VarDecl *VD,

                                      DynamicInitKind StubKind,

                                      llvm::Function *InitFn);

  /// Get line number for the location. If location is invalid

  /// then use current location.

  unsigned getLineNumber(SourceLocation Loc);

  /// Get column number for the location. If location is

  /// invalid then use current location.

  /// \param Force  Assume DebugColumnInfo option is true.

  unsigned getColumnNumber(SourceLocation Loc, bool Force = false);

  /// Collect various properties of a FunctionDecl.

  /// \param GD  A GlobalDecl whose getDecl() must return a FunctionDecl.

  void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,

                                StringRef &Name, StringRef &LinkageName,

                                llvm::DIScope *&FDContext,

                                llvm::DINodeArray &TParamsArray,

                                llvm::DINode::DIFlags &Flags);

  /// Collect various properties of a VarDecl.

  void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,

                           unsigned &LineNo, QualType &T, StringRef &Name,

                           StringRef &LinkageName,

                           llvm::MDTuple *&TemplateParameters,

                           llvm::DIScope *&VDContext);

  /// Allocate a copy of \p A using the DebugInfoNames allocator

  /// and return a reference to it. If multiple arguments are given the strings

  /// are concatenated.

  StringRef internString(StringRef A, StringRef B = StringRef()) {

    char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());

    if (!A.empty())

      std::memcpy(Data, A.data(), A.size());

    if (!B.empty())

      std::memcpy(Data + A.size(), B.data(), B.size());

    return StringRef(Data, A.size() + B.size());

  }

};

/// A scoped helper to set the current debug location to the specified

/// location or preferred location of the specified Expr.

class ApplyDebugLocation {

private:

  void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false);

  ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty,

                     SourceLocation TemporaryLocation);

  llvm::DebugLoc OriginalLocation;

  CodeGenFunction *CGF;

public:

  /// Set the location to the (valid) TemporaryLocation.

  ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);

  ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);

  ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);

  ApplyDebugLocation(ApplyDebugLocation &&Other) : CGF(Other.CGF) {

    Other.CGF = nullptr;

  }

  // Define copy assignment operator.

  ApplyDebugLocation &operator=(ApplyDebugLocation &&Other) {

    CGF = Other.CGF;

    Other.CGF = nullptr;

    return *this;

  }

  ~ApplyDebugLocation();

  /// Apply TemporaryLocation if it is valid. Otherwise switch

  /// to an artificial debug location that has a valid scope, but no

  /// line information.

  ///

  /// Artificial locations are useful when emitting compiler-generated

  /// helper functions that have no source location associated with

  /// them. The DWARF specification allows the compiler to use the

  /// special line number 0 to indicate code that can not be

  /// attributed to any source location. Note that passing an empty

  /// SourceLocation to CGDebugInfo::setLocation() will result in the

  /// last valid location being reused.

  static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) {

    return ApplyDebugLocation(CGF, false, SourceLocation());

  }

  /// Apply TemporaryLocation if it is valid. Otherwise switch

  /// to an artificial debug location that has a valid scope, but no

  /// line information.

  static ApplyDebugLocation

  CreateDefaultArtificial(CodeGenFunction &CGF,

                          SourceLocation TemporaryLocation) {

    return ApplyDebugLocation(CGF, false, TemporaryLocation);

  }

  /// Set the IRBuilder to not attach debug locations.  Note that

  /// passing an empty SourceLocation to \a CGDebugInfo::setLocation()

  /// will result in the last valid location being reused.  Note that

  /// all instructions that do not have a location at the beginning of

  /// a function are counted towards to function prologue.

  static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) {

    return ApplyDebugLocation(CGF, true, SourceLocation());

  }

};

/// A scoped helper to set the current debug location to an inlined location.

class ApplyInlineDebugLocation {

  SourceLocation SavedLocation;

  CodeGenFunction *CGF;

public:

  /// Set up the CodeGenFunction's DebugInfo to produce inline locations for the

  /// function \p InlinedFn. The current debug location becomes the inlined call

  /// site of the inlined function.

  ApplyInlineDebugLocation(CodeGenFunction &CGF, GlobalDecl InlinedFn);

  /// Restore everything back to the original state.

  ~ApplyInlineDebugLocation();

};

} // namespace CodeGen

} // namespace clang

#endif // LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H