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/ADT/Optional.h"
29#include "llvm/IR/DIBuilder.h"
30#include "llvm/IR/DebugInfo.h"
31#include "llvm/IR/ValueHandle.h"
32#include "llvm/Support/Allocator.h"
33
34namespace llvm {
35class MDNode;
36}
37
38namespace clang {
39class ClassTemplateSpecializationDecl;
40class GlobalDecl;
41class ModuleMap;
42class ObjCInterfaceDecl;
43class ObjCIvarDecl;
44class UsingDecl;
45class VarDecl;
46enum class DynamicInitKind : unsigned;
47
48namespace CodeGen {
49class CodeGenModule;
50class CodeGenFunction;
51class CGBlockInfo;
52
53/// This class gathers all debug information during compilation and is
54/// responsible for emitting to llvm globals or pass directly to the
55/// backend.
56class CGDebugInfo {
57  friend class ApplyDebugLocation;
58  friend class SaveAndRestoreLocation;
59  CodeGenModule &CGM;
60  const codegenoptions::DebugInfoKind DebugKind;
61  bool DebugTypeExtRefs;
62  llvm::DIBuilder DBuilder;
63  llvm::DICompileUnit *TheCU = nullptr;
64  ModuleMap *ClangModuleMap = nullptr;
65  ASTSourceDescriptor PCHDescriptor;
66  SourceLocation CurLoc;
67  llvm::MDNode *CurInlinedAt = nullptr;
68  llvm::DIType *VTablePtrType = nullptr;
69  llvm::DIType *ClassTy = nullptr;
70  llvm::DICompositeType *ObjTy = nullptr;
71  llvm::DIType *SelTy = nullptr;
72#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \
73  llvm::DIType *SingletonId = nullptr;
74#include "clang/Basic/OpenCLImageTypes.def"
75  llvm::DIType *OCLSamplerDITy = nullptr;
76  llvm::DIType *OCLEventDITy = nullptr;
77  llvm::DIType *OCLClkEventDITy = nullptr;
78  llvm::DIType *OCLQueueDITy = nullptr;
79  llvm::DIType *OCLNDRangeDITy = nullptr;
80  llvm::DIType *OCLReserveIDDITy = nullptr;
81#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
82  llvm::DIType *Id##Ty = nullptr;
83#include "clang/Basic/OpenCLExtensionTypes.def"
84
85  /// Cache of previously constructed Types.
86  llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache;
87
88  std::map<llvm::StringRef, llvm::StringRef, std::greater<llvm::StringRef>>
89      DebugPrefixMap;
90
91  /// Cache that maps VLA types to size expressions for that type,
92  /// represented by instantiated Metadata nodes.
93  llvm::SmallDenseMap<QualType, llvm::Metadata *> SizeExprCache;
94
95  /// Callbacks to use when printing names and types.
96  class PrintingCallbacks final : public clang::PrintingCallbacks {
97    const CGDebugInfo &Self;
98
99  public:
100    PrintingCallbacks(const CGDebugInfo &Self) : Self(Self) {}
101    std::string remapPath(StringRef Path) const override {
102      return Self.remapDIPath(Path);
103    }
104  };
105  PrintingCallbacks PrintCB = {*this};
106
107  struct ObjCInterfaceCacheEntry {
108    const ObjCInterfaceType *Type;
109    llvm::DIType *Decl;
110    llvm::DIFile *Unit;
111    ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl,
112                            llvm::DIFile *Unit)
113        : Type(Type), Decl(Decl), Unit(Unit) {}
114  };
115
116  /// Cache of previously constructed interfaces which may change.
117  llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;
118
119  /// Cache of forward declarations for methods belonging to the interface.
120  /// The extra bit on the DISubprogram specifies whether a method is
121  /// "objc_direct".
122  llvm::DenseMap<const ObjCInterfaceDecl *,
123                 std::vector<llvm::PointerIntPair<llvm::DISubprogram *, 1>>>
124      ObjCMethodCache;
125
126  /// Cache of references to clang modules and precompiled headers.
127  llvm::DenseMap<const Module *, llvm::TrackingMDRef> ModuleCache;
128
129  /// List of interfaces we want to keep even if orphaned.
130  std::vector<void *> RetainedTypes;
131
132  /// Cache of forward declared types to RAUW at the end of compilation.
133  std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap;
134
135  /// Cache of replaceable forward declarations (functions and
136  /// variables) to RAUW at the end of compilation.
137  std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>>
138      FwdDeclReplaceMap;
139
140  /// Keep track of our current nested lexical block.
141  std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;
142  llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;
143  /// Keep track of LexicalBlockStack counter at the beginning of a
144  /// function. This is used to pop unbalanced regions at the end of a
145  /// function.
146  std::vector<unsigned> FnBeginRegionCount;
147
148  /// This is a storage for names that are constructed on demand. For
149  /// example, C++ destructors, C++ operators etc..
150  llvm::BumpPtrAllocator DebugInfoNames;
151  StringRef CWDName;
152
153  llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;
154  llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;
155  /// Cache declarations relevant to DW_TAG_imported_declarations (C++
156  /// using declarations) that aren't covered by other more specific caches.
157  llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache;
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  /// Helper functions for getOrCreateType.
165  /// @{
166  /// Currently the checksum of an interface includes the number of
167  /// ivars and property accessors.
168  llvm::DIType *CreateType(const BuiltinType *Ty);
169  llvm::DIType *CreateType(const ComplexType *Ty);
170  llvm::DIType *CreateType(const AutoType *Ty);
171  llvm::DIType *CreateType(const ExtIntType *Ty);
172  llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg);
173  llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg);
174  llvm::DIType *CreateType(const TemplateSpecializationType *Ty,
175                           llvm::DIFile *Fg);
176  llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F);
177  llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F);
178  llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F);
179  llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F);
180  /// Get structure or union type.
181  llvm::DIType *CreateType(const RecordType *Tyg);
182  llvm::DIType *CreateTypeDefinition(const RecordType *Ty);
183  llvm::DICompositeType *CreateLimitedType(const RecordType *Ty);
184  void CollectContainingType(const CXXRecordDecl *RD,
185                             llvm::DICompositeType *CT);
186  /// Get Objective-C interface type.
187  llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F);
188  llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty,
189                                     llvm::DIFile *F);
190  /// Get Objective-C object type.
191  llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F);
192  llvm::DIType *CreateType(const ObjCTypeParamType *Ty, llvm::DIFile *Unit);
193
194  llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F);
195  llvm::DIType *CreateType(const ConstantMatrixType *Ty, llvm::DIFile *F);
196  llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F);
197  llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F);
198  llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit);
199  llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F);
200  llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F);
201  llvm::DIType *CreateType(const PipeType *Ty, llvm::DIFile *F);
202  /// Get enumeration type.
203  llvm::DIType *CreateEnumType(const EnumType *Ty);
204  llvm::DIType *CreateTypeDefinition(const EnumType *Ty);
205  /// Look up the completed type for a self pointer in the TypeCache and
206  /// create a copy of it with the ObjectPointer and Artificial flags
207  /// set. If the type is not cached, a new one is created. This should
208  /// never happen though, since creating a type for the implicit self
209  /// argument implies that we already parsed the interface definition
210  /// and the ivar declarations in the implementation.
211  llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty);
212  /// @}
213
214  /// Get the type from the cache or return null type if it doesn't
215  /// exist.
216  llvm::DIType *getTypeOrNull(const QualType);
217  /// Return the debug type for a C++ method.
218  /// \arg CXXMethodDecl is of FunctionType. This function type is
219  /// not updated to include implicit \c this pointer. Use this routine
220  /// to get a method type which includes \c this pointer.
221  llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method,
222                                                llvm::DIFile *F, bool decl);
223  llvm::DISubroutineType *
224  getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func,
225                                llvm::DIFile *Unit, bool decl);
226  llvm::DISubroutineType *
227  getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F);
228  /// \return debug info descriptor for vtable.
229  llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F);
230
231  /// \return namespace descriptor for the given namespace decl.
232  llvm::DINamespace *getOrCreateNamespace(const NamespaceDecl *N);
233  llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty,
234                                      QualType PointeeTy, llvm::DIFile *F);
235  llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache);
236
237  /// A helper function to create a subprogram for a single member
238  /// function GlobalDecl.
239  llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method,
240                                              llvm::DIFile *F,
241                                              llvm::DIType *RecordTy);
242
243  /// A helper function to collect debug info for C++ member
244  /// functions. This is used while creating debug info entry for a
245  /// Record.
246  void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F,
247                                 SmallVectorImpl<llvm::Metadata *> &E,
248                                 llvm::DIType *T);
249
250  /// A helper function to collect debug info for C++ base
251  /// classes. This is used while creating debug info entry for a
252  /// Record.
253  void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F,
254                       SmallVectorImpl<llvm::Metadata *> &EltTys,
255                       llvm::DIType *RecordTy);
256
257  /// Helper function for CollectCXXBases.
258  /// Adds debug info entries for types in Bases that are not in SeenTypes.
259  void CollectCXXBasesAux(
260      const CXXRecordDecl *RD, llvm::DIFile *Unit,
261      SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy,
262      const CXXRecordDecl::base_class_const_range &Bases,
263      llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> &SeenTypes,
264      llvm::DINode::DIFlags StartingFlags);
265
266  /// A helper function to collect template parameters.
267  llvm::DINodeArray CollectTemplateParams(const TemplateParameterList *TPList,
268                                          ArrayRef<TemplateArgument> TAList,
269                                          llvm::DIFile *Unit);
270  /// A helper function to collect debug info for function template
271  /// parameters.
272  llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD,
273                                                  llvm::DIFile *Unit);
274
275  /// A helper function to collect debug info for function template
276  /// parameters.
277  llvm::DINodeArray CollectVarTemplateParams(const VarDecl *VD,
278                                             llvm::DIFile *Unit);
279
280  /// A helper function to collect debug info for template
281  /// parameters.
282  llvm::DINodeArray
283  CollectCXXTemplateParams(const ClassTemplateSpecializationDecl *TS,
284                           llvm::DIFile *F);
285
286  llvm::DIType *createFieldType(StringRef name, QualType type,
287                                SourceLocation loc, AccessSpecifier AS,
288                                uint64_t offsetInBits, uint32_t AlignInBits,
289                                llvm::DIFile *tunit, llvm::DIScope *scope,
290                                const RecordDecl *RD = nullptr);
291
292  llvm::DIType *createFieldType(StringRef name, QualType type,
293                                SourceLocation loc, AccessSpecifier AS,
294                                uint64_t offsetInBits, llvm::DIFile *tunit,
295                                llvm::DIScope *scope,
296                                const RecordDecl *RD = nullptr) {
297    return createFieldType(name, type, loc, AS, offsetInBits, 0, tunit, scope,
298                           RD);
299  }
300
301  /// Create new bit field member.
302  llvm::DIType *createBitFieldType(const FieldDecl *BitFieldDecl,
303                                   llvm::DIScope *RecordTy,
304                                   const RecordDecl *RD);
305
306  /// Helpers for collecting fields of a record.
307  /// @{
308  void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,
309                                 SmallVectorImpl<llvm::Metadata *> &E,
310                                 llvm::DIType *RecordTy);
311  llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var,
312                                               llvm::DIType *RecordTy,
313                                               const RecordDecl *RD);
314  void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,
315                                llvm::DIFile *F,
316                                SmallVectorImpl<llvm::Metadata *> &E,
317                                llvm::DIType *RecordTy, const RecordDecl *RD);
318  void CollectRecordNestedType(const TypeDecl *RD,
319                               SmallVectorImpl<llvm::Metadata *> &E);
320  void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F,
321                           SmallVectorImpl<llvm::Metadata *> &E,
322                           llvm::DICompositeType *RecordTy);
323
324  /// If the C++ class has vtable info then insert appropriate debug
325  /// info entry in EltTys vector.
326  void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F,
327                         SmallVectorImpl<llvm::Metadata *> &EltTys,
328                         llvm::DICompositeType *RecordTy);
329  /// @}
330
331  /// Create a new lexical block node and push it on the stack.
332  void CreateLexicalBlock(SourceLocation Loc);
333
334  /// If target-specific LLVM \p AddressSpace directly maps to target-specific
335  /// DWARF address space, appends extended dereferencing mechanism to complex
336  /// expression \p Expr. Otherwise, does nothing.
337  ///
338  /// Extended dereferencing mechanism is has the following format:
339  ///     DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef
340  void AppendAddressSpaceXDeref(unsigned AddressSpace,
341                                SmallVectorImpl<int64_t> &Expr) const;
342
343  /// A helper function to collect debug info for the default elements of a
344  /// block.
345  ///
346  /// \returns The next available field offset after the default elements.
347  uint64_t collectDefaultElementTypesForBlockPointer(
348      const BlockPointerType *Ty, llvm::DIFile *Unit,
349      llvm::DIDerivedType *DescTy, unsigned LineNo,
350      SmallVectorImpl<llvm::Metadata *> &EltTys);
351
352  /// A helper function to collect debug info for the default fields of a
353  /// block.
354  void collectDefaultFieldsForBlockLiteralDeclare(
355      const CGBlockInfo &Block, const ASTContext &Context, SourceLocation Loc,
356      const llvm::StructLayout &BlockLayout, llvm::DIFile *Unit,
357      SmallVectorImpl<llvm::Metadata *> &Fields);
358
359public:
360  CGDebugInfo(CodeGenModule &CGM);
361  ~CGDebugInfo();
362
363  void finalize();
364
365  /// Remap a given path with the current debug prefix map
366  std::string remapDIPath(StringRef) const;
367
368  /// Register VLA size expression debug node with the qualified type.
369  void registerVLASizeExpression(QualType Ty, llvm::Metadata *SizeExpr) {
370    SizeExprCache[Ty] = SizeExpr;
371  }
372
373  /// Module debugging: Support for building PCMs.
374  /// @{
375  /// Set the main CU's DwoId field to \p Signature.
376  void setDwoId(uint64_t Signature);
377
378  /// When generating debug information for a clang module or
379  /// precompiled header, this module map will be used to determine
380  /// the module of origin of each Decl.
381  void setModuleMap(ModuleMap &MMap) { ClangModuleMap = &MMap; }
382
383  /// When generating debug information for a clang module or
384  /// precompiled header, this module map will be used to determine
385  /// the module of origin of each Decl.
386  void setPCHDescriptor(ASTSourceDescriptor PCH) { PCHDescriptor = PCH; }
387  /// @}
388
389  /// Update the current source location. If \arg loc is invalid it is
390  /// ignored.
391  void setLocation(SourceLocation Loc);
392
393  /// Return the current source location. This does not necessarily correspond
394  /// to the IRBuilder's current DebugLoc.
395  SourceLocation getLocation() const { return CurLoc; }
396
397  /// Update the current inline scope. All subsequent calls to \p EmitLocation
398  /// will create a location with this inlinedAt field.
399  void setInlinedAt(llvm::MDNode *InlinedAt) { CurInlinedAt = InlinedAt; }
400
401  /// \return the current inline scope.
402  llvm::MDNode *getInlinedAt() const { return CurInlinedAt; }
403
404  // Converts a SourceLocation to a DebugLoc
405  llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Loc);
406
407  /// Emit metadata to indicate a change in line/column information in
408  /// the source file. If the location is invalid, the previous
409  /// location will be reused.
410  void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc);
411
412  /// Emit a call to llvm.dbg.function.start to indicate
413  /// start of a new function.
414  /// \param Loc       The location of the function header.
415  /// \param ScopeLoc  The location of the function body.
416  void EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
417                         SourceLocation ScopeLoc, QualType FnType,
418                         llvm::Function *Fn, bool CurFnIsThunk,
419                         CGBuilderTy &Builder);
420
421  /// Start a new scope for an inlined function.
422  void EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD);
423  /// End an inlined function scope.
424  void EmitInlineFunctionEnd(CGBuilderTy &Builder);
425
426  /// Emit debug info for a function declaration.
427  /// \p Fn is set only when a declaration for a debug call site gets created.
428  void EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
429                        QualType FnType, llvm::Function *Fn = nullptr);
430
431  /// Emit debug info for an extern function being called.
432  /// This is needed for call site debug info.
433  void EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
434                               QualType CalleeType,
435                               const FunctionDecl *CalleeDecl);
436
437  /// Constructs the debug code for exiting a function.
438  void EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn);
439
440  /// Emit metadata to indicate the beginning of a new lexical block
441  /// and push the block onto the stack.
442  void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);
443
444  /// Emit metadata to indicate the end of a new lexical block and pop
445  /// the current block.
446  void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);
447
448  /// Emit call to \c llvm.dbg.declare for an automatic variable
449  /// declaration.
450  /// Returns a pointer to the DILocalVariable associated with the
451  /// llvm.dbg.declare, or nullptr otherwise.
452  llvm::DILocalVariable *
453  EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,
454                            CGBuilderTy &Builder,
455                            const bool UsePointerValue = false);
456
457  /// Emit call to \c llvm.dbg.label for an label.
458  void EmitLabel(const LabelDecl *D, CGBuilderTy &Builder);
459
460  /// Emit call to \c llvm.dbg.declare for an imported variable
461  /// declaration in a block.
462  void EmitDeclareOfBlockDeclRefVariable(
463      const VarDecl *variable, llvm::Value *storage, CGBuilderTy &Builder,
464      const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint = nullptr);
465
466  /// Emit call to \c llvm.dbg.declare for an argument variable
467  /// declaration.
468  void EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI,
469                                unsigned ArgNo, CGBuilderTy &Builder);
470
471  /// Emit call to \c llvm.dbg.declare for the block-literal argument
472  /// to a block invocation function.
473  void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
474                                            StringRef Name, unsigned ArgNo,
475                                            llvm::AllocaInst *LocalAddr,
476                                            CGBuilderTy &Builder);
477
478  /// Emit information about a global variable.
479  void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
480
481  /// Emit a constant global variable's debug info.
482  void EmitGlobalVariable(const ValueDecl *VD, const APValue &Init);
483
484  /// Emit information about an external variable.
485  void EmitExternalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
486
487  /// Emit C++ using directive.
488  void EmitUsingDirective(const UsingDirectiveDecl &UD);
489
490  /// Emit the type explicitly casted to.
491  void EmitExplicitCastType(QualType Ty);
492
493  /// Emit C++ using declaration.
494  void EmitUsingDecl(const UsingDecl &UD);
495
496  /// Emit an @import declaration.
497  void EmitImportDecl(const ImportDecl &ID);
498
499  /// Emit C++ namespace alias.
500  llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA);
501
502  /// Emit record type's standalone debug info.
503  llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L);
504
505  /// Emit an Objective-C interface type standalone debug info.
506  llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);
507
508  /// Emit standalone debug info for a type.
509  llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);
510
511  /// Add heapallocsite metadata for MSAllocator calls.
512  void addHeapAllocSiteMetadata(llvm::CallBase *CallSite, QualType AllocatedTy,
513                                SourceLocation Loc);
514
515  void completeType(const EnumDecl *ED);
516  void completeType(const RecordDecl *RD);
517  void completeRequiredType(const RecordDecl *RD);
518  void completeClassData(const RecordDecl *RD);
519  void completeClass(const RecordDecl *RD);
520
521  void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);
522  void completeUnusedClass(const CXXRecordDecl &D);
523
524  /// Create debug info for a macro defined by a #define directive or a macro
525  /// undefined by a #undef directive.
526  llvm::DIMacro *CreateMacro(llvm::DIMacroFile *Parent, unsigned MType,
527                             SourceLocation LineLoc, StringRef Name,
528                             StringRef Value);
529
530  /// Create debug info for a file referenced by an #include directive.
531  llvm::DIMacroFile *CreateTempMacroFile(llvm::DIMacroFile *Parent,
532                                         SourceLocation LineLoc,
533                                         SourceLocation FileLoc);
534
535private:
536  /// Emit call to llvm.dbg.declare for a variable declaration.
537  /// Returns a pointer to the DILocalVariable associated with the
538  /// llvm.dbg.declare, or nullptr otherwise.
539  llvm::DILocalVariable *EmitDeclare(const VarDecl *decl, llvm::Value *AI,
540                                     llvm::Optional<unsigned> ArgNo,
541                                     CGBuilderTy &Builder,
542                                     const bool UsePointerValue = false);
543
544  struct BlockByRefType {
545    /// The wrapper struct used inside the __block_literal struct.
546    llvm::DIType *BlockByRefWrapper;
547    /// The type as it appears in the source code.
548    llvm::DIType *WrappedType;
549  };
550
551  /// Build up structure info for the byref.  See \a BuildByRefType.
552  BlockByRefType EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
553                                              uint64_t *OffSet);
554
555  /// Get context info for the DeclContext of \p Decl.
556  llvm::DIScope *getDeclContextDescriptor(const Decl *D);
557  /// Get context info for a given DeclContext \p Decl.
558  llvm::DIScope *getContextDescriptor(const Decl *Context,
559                                      llvm::DIScope *Default);
560
561  llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl);
562
563  /// Create a forward decl for a RecordType in a given context.
564  llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *,
565                                                  llvm::DIScope *);
566
567  /// Return current directory name.
568  StringRef getCurrentDirname();
569
570  /// Create new compile unit.
571  void CreateCompileUnit();
572
573  /// Compute the file checksum debug info for input file ID.
574  Optional<llvm::DIFile::ChecksumKind>
575  computeChecksum(FileID FID, SmallString<32> &Checksum) const;
576
577  /// Get the source of the given file ID.
578  Optional<StringRef> getSource(const SourceManager &SM, FileID FID);
579
580  /// Convenience function to get the file debug info descriptor for the input
581  /// location.
582  llvm::DIFile *getOrCreateFile(SourceLocation Loc);
583
584  /// Create a file debug info descriptor for a source file.
585  llvm::DIFile *
586  createFile(StringRef FileName,
587             Optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo,
588             Optional<StringRef> Source);
589
590  /// Get the type from the cache or create a new type if necessary.
591  llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg);
592
593  /// Get a reference to a clang module.  If \p CreateSkeletonCU is true,
594  /// this also creates a split dwarf skeleton compile unit.
595  llvm::DIModule *getOrCreateModuleRef(ASTSourceDescriptor Mod,
596                                       bool CreateSkeletonCU);
597
598  /// DebugTypeExtRefs: If \p D originated in a clang module, return it.
599  llvm::DIModule *getParentModuleOrNull(const Decl *D);
600
601  /// Get the type from the cache or create a new partial type if
602  /// necessary.
603  llvm::DICompositeType *getOrCreateLimitedType(const RecordType *Ty,
604                                                llvm::DIFile *F);
605
606  /// Create type metadata for a source language type.
607  llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg);
608
609  /// Create new member and increase Offset by FType's size.
610  llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType,
611                                 StringRef Name, uint64_t *Offset);
612
613  /// Retrieve the DIDescriptor, if any, for the canonical form of this
614  /// declaration.
615  llvm::DINode *getDeclarationOrDefinition(const Decl *D);
616
617  /// \return debug info descriptor to describe method
618  /// declaration for the given method definition.
619  llvm::DISubprogram *getFunctionDeclaration(const Decl *D);
620
621  /// \return          debug info descriptor to the describe method declaration
622  ///                  for the given method definition.
623  /// \param FnType    For Objective-C methods, their type.
624  /// \param LineNo    The declaration's line number.
625  /// \param Flags     The DIFlags for the method declaration.
626  /// \param SPFlags   The subprogram-spcific flags for the method declaration.
627  llvm::DISubprogram *
628  getObjCMethodDeclaration(const Decl *D, llvm::DISubroutineType *FnType,
629                           unsigned LineNo, llvm::DINode::DIFlags Flags,
630                           llvm::DISubprogram::DISPFlags SPFlags);
631
632  /// \return debug info descriptor to describe in-class static data
633  /// member declaration for the given out-of-class definition.  If D
634  /// is an out-of-class definition of a static data member of a
635  /// class, find its corresponding in-class declaration.
636  llvm::DIDerivedType *
637  getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);
638
639  /// Helper that either creates a forward declaration or a stub.
640  llvm::DISubprogram *getFunctionFwdDeclOrStub(GlobalDecl GD, bool Stub);
641
642  /// Create a subprogram describing the forward declaration
643  /// represented in the given FunctionDecl wrapped in a GlobalDecl.
644  llvm::DISubprogram *getFunctionForwardDeclaration(GlobalDecl GD);
645
646  /// Create a DISubprogram describing the function
647  /// represented in the given FunctionDecl wrapped in a GlobalDecl.
648  llvm::DISubprogram *getFunctionStub(GlobalDecl GD);
649
650  /// Create a global variable describing the forward declaration
651  /// represented in the given VarDecl.
652  llvm::DIGlobalVariable *
653  getGlobalVariableForwardDeclaration(const VarDecl *VD);
654
655  /// Return a global variable that represents one of the collection of global
656  /// variables created for an anonmyous union.
657  ///
658  /// Recursively collect all of the member fields of a global
659  /// anonymous decl and create static variables for them. The first
660  /// time this is called it needs to be on a union and then from
661  /// there we can have additional unnamed fields.
662  llvm::DIGlobalVariableExpression *
663  CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit,
664                         unsigned LineNo, StringRef LinkageName,
665                         llvm::GlobalVariable *Var, llvm::DIScope *DContext);
666
667
668  /// Return flags which enable debug info emission for call sites, provided
669  /// that it is supported and enabled.
670  llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;
671
672  /// Get the printing policy for producing names for debug info.
673  PrintingPolicy getPrintingPolicy() const;
674
675  /// Get function name for the given FunctionDecl. If the name is
676  /// constructed on demand (e.g., C++ destructor) then the name is
677  /// stored on the side.
678  StringRef getFunctionName(const FunctionDecl *FD);
679
680  /// Returns the unmangled name of an Objective-C method.
681  /// This is the display name for the debugging info.
682  StringRef getObjCMethodName(const ObjCMethodDecl *FD);
683
684  /// Return selector name. This is used for debugging
685  /// info.
686  StringRef getSelectorName(Selector S);
687
688  /// Get class name including template argument list.
689  StringRef getClassName(const RecordDecl *RD);
690
691  /// Get the vtable name for the given class.
692  StringRef getVTableName(const CXXRecordDecl *Decl);
693
694  /// Get the name to use in the debug info for a dynamic initializer or atexit
695  /// stub function.
696  StringRef getDynamicInitializerName(const VarDecl *VD,
697                                      DynamicInitKind StubKind,
698                                      llvm::Function *InitFn);
699
700  /// Get line number for the location. If location is invalid
701  /// then use current location.
702  unsigned getLineNumber(SourceLocation Loc);
703
704  /// Get column number for the location. If location is
705  /// invalid then use current location.
706  /// \param Force  Assume DebugColumnInfo option is true.
707  unsigned getColumnNumber(SourceLocation Loc, bool Force = false);
708
709  /// Collect various properties of a FunctionDecl.
710  /// \param GD  A GlobalDecl whose getDecl() must return a FunctionDecl.
711  void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
712                                StringRef &Name, StringRef &LinkageName,
713                                llvm::DIScope *&FDContext,
714                                llvm::DINodeArray &TParamsArray,
715                                llvm::DINode::DIFlags &Flags);
716
717  /// Collect various properties of a VarDecl.
718  void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
719                           unsigned &LineNo, QualType &T, StringRef &Name,
720                           StringRef &LinkageName,
721                           llvm::MDTuple *&TemplateParameters,
722                           llvm::DIScope *&VDContext);
723
724  /// Allocate a copy of \p A using the DebugInfoNames allocator
725  /// and return a reference to it. If multiple arguments are given the strings
726  /// are concatenated.
727  StringRef internString(StringRef A, StringRef B = StringRef()) {
728    char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());
729    if (!A.empty())
730      std::memcpy(Data, A.data(), A.size());
731    if (!B.empty())
732      std::memcpy(Data + A.size(), B.data(), B.size());
733    return StringRef(Data, A.size() + B.size());
734  }
735};
736
737/// A scoped helper to set the current debug location to the specified
738/// location or preferred location of the specified Expr.
739class ApplyDebugLocation {
740private:
741  void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false);
742  ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty,
743                     SourceLocation TemporaryLocation);
744
745  llvm::DebugLoc OriginalLocation;
746  CodeGenFunction *CGF;
747
748public:
749  /// Set the location to the (valid) TemporaryLocation.
750  ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);
751  ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);
752  ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);
753  ApplyDebugLocation(ApplyDebugLocation &&Other) : CGF(Other.CGF) {
754    Other.CGF = nullptr;
755  }
756  ApplyDebugLocation &operator=(ApplyDebugLocation &&) = default;
757
758  ~ApplyDebugLocation();
759
760  /// Apply TemporaryLocation if it is valid. Otherwise switch
761  /// to an artificial debug location that has a valid scope, but no
762  /// line information.
763  ///
764  /// Artificial locations are useful when emitting compiler-generated
765  /// helper functions that have no source location associated with
766  /// them. The DWARF specification allows the compiler to use the
767  /// special line number 0 to indicate code that can not be
768  /// attributed to any source location. Note that passing an empty
769  /// SourceLocation to CGDebugInfo::setLocation() will result in the
770  /// last valid location being reused.
771  static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) {
772    return ApplyDebugLocation(CGF, false, SourceLocation());
773  }
774  /// Apply TemporaryLocation if it is valid. Otherwise switch
775  /// to an artificial debug location that has a valid scope, but no
776  /// line information.
777  static ApplyDebugLocation
778  CreateDefaultArtificial(CodeGenFunction &CGF,
779                          SourceLocation TemporaryLocation) {
780    return ApplyDebugLocation(CGF, false, TemporaryLocation);
781  }
782
783  /// Set the IRBuilder to not attach debug locations.  Note that
784  /// passing an empty SourceLocation to \a CGDebugInfo::setLocation()
785  /// will result in the last valid location being reused.  Note that
786  /// all instructions that do not have a location at the beginning of
787  /// a function are counted towards to function prologue.
788  static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) {
789    return ApplyDebugLocation(CGF, true, SourceLocation());
790  }
791};
792
793/// A scoped helper to set the current debug location to an inlined location.
794class ApplyInlineDebugLocation {
795  SourceLocation SavedLocation;
796  CodeGenFunction *CGF;
797
798public:
799  /// Set up the CodeGenFunction's DebugInfo to produce inline locations for the
800  /// function \p InlinedFn. The current debug location becomes the inlined call
801  /// site of the inlined function.
802  ApplyInlineDebugLocation(CodeGenFunction &CGF, GlobalDecl InlinedFn);
803  /// Restore everything back to the original state.
804  ~ApplyInlineDebugLocation();
805};
806
807} // namespace CodeGen
808} // namespace clang
809
810#endif // LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H
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