1 //===--- CGDebugInfo.h - DebugInfo for LLVM CodeGen -------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This is the source-level debug info generator for llvm translation.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H
15 #define LLVM_CLANG_LIB_CODEGEN_CGDEBUGINFO_H
17 #include "CGBuilder.h"
18 #include "clang/AST/Expr.h"
19 #include "clang/AST/Type.h"
20 #include "clang/Basic/SourceLocation.h"
21 #include "clang/Frontend/CodeGenOptions.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/IR/DIBuilder.h"
24 #include "llvm/IR/DebugInfo.h"
25 #include "llvm/IR/ValueHandle.h"
26 #include "llvm/Support/Allocator.h"
35 class ObjCInterfaceDecl;
37 class ClassTemplateSpecializationDecl;
43 class CodeGenFunction;
46 /// This class gathers all debug information during compilation and is
47 /// responsible for emitting to llvm globals or pass directly to the
50 friend class ApplyDebugLocation;
51 friend class SaveAndRestoreLocation;
53 const CodeGenOptions::DebugInfoKind DebugKind;
54 llvm::DIBuilder DBuilder;
55 llvm::DICompileUnit *TheCU = nullptr;
56 SourceLocation CurLoc;
57 llvm::DIType *VTablePtrType = nullptr;
58 llvm::DIType *ClassTy = nullptr;
59 llvm::DICompositeType *ObjTy = nullptr;
60 llvm::DIType *SelTy = nullptr;
61 llvm::DIType *OCLImage1dDITy = nullptr;
62 llvm::DIType *OCLImage1dArrayDITy = nullptr;
63 llvm::DIType *OCLImage1dBufferDITy = nullptr;
64 llvm::DIType *OCLImage2dDITy = nullptr;
65 llvm::DIType *OCLImage2dArrayDITy = nullptr;
66 llvm::DIType *OCLImage3dDITy = nullptr;
67 llvm::DIType *OCLEventDITy = nullptr;
69 /// Cache of previously constructed Types.
70 llvm::DenseMap<const void *, llvm::TrackingMDRef> TypeCache;
72 struct ObjCInterfaceCacheEntry {
73 const ObjCInterfaceType *Type;
76 ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType *Decl,
78 : Type(Type), Decl(Decl), Unit(Unit) {}
81 /// Cache of previously constructed interfaces which may change.
82 llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;
84 /// Cache of references to AST files such as PCHs or modules.
85 llvm::DenseMap<uint64_t, llvm::DIModule *> ModuleRefCache;
87 /// List of interfaces we want to keep even if orphaned.
88 std::vector<void *> RetainedTypes;
90 /// Cache of forward declared types to RAUW at the end of
92 std::vector<std::pair<const TagType *, llvm::TrackingMDRef>> ReplaceMap;
94 /// Cache of replaceable forward declarartions (functions and
95 /// variables) to RAUW at the end of compilation.
96 std::vector<std::pair<const DeclaratorDecl *, llvm::TrackingMDRef>>
99 /// Keep track of our current nested lexical block.
100 std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;
101 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;
102 /// Keep track of LexicalBlockStack counter at the beginning of a
103 /// function. This is used to pop unbalanced regions at the end of a
105 std::vector<unsigned> FnBeginRegionCount;
107 /// This is a storage for names that are constructed on demand. For
108 /// example, C++ destructors, C++ operators etc..
109 llvm::BumpPtrAllocator DebugInfoNames;
112 llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;
113 llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;
114 /// Cache declarations relevant to DW_TAG_imported_declarations (C++
115 /// using declarations) that aren't covered by other more specific caches.
116 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> DeclCache;
117 llvm::DenseMap<const NamespaceDecl *, llvm::TrackingMDRef> NameSpaceCache;
118 llvm::DenseMap<const NamespaceAliasDecl *, llvm::TrackingMDRef>
120 llvm::DenseMap<const Decl *, llvm::TrackingMDRef> StaticDataMemberCache;
122 /// Helper functions for getOrCreateType.
124 /// Currently the checksum of an interface includes the number of
125 /// ivars and property accessors.
126 unsigned Checksum(const ObjCInterfaceDecl *InterfaceDecl);
127 llvm::DIType *CreateType(const BuiltinType *Ty);
128 llvm::DIType *CreateType(const ComplexType *Ty);
129 llvm::DIType *CreateQualifiedType(QualType Ty, llvm::DIFile *Fg);
130 llvm::DIType *CreateType(const TypedefType *Ty, llvm::DIFile *Fg);
131 llvm::DIType *CreateType(const TemplateSpecializationType *Ty,
133 llvm::DIType *CreateType(const ObjCObjectPointerType *Ty, llvm::DIFile *F);
134 llvm::DIType *CreateType(const PointerType *Ty, llvm::DIFile *F);
135 llvm::DIType *CreateType(const BlockPointerType *Ty, llvm::DIFile *F);
136 llvm::DIType *CreateType(const FunctionType *Ty, llvm::DIFile *F);
137 /// Get structure or union type.
138 llvm::DIType *CreateType(const RecordType *Tyg);
139 llvm::DIType *CreateTypeDefinition(const RecordType *Ty);
140 llvm::DICompositeType *CreateLimitedType(const RecordType *Ty);
141 void CollectContainingType(const CXXRecordDecl *RD,
142 llvm::DICompositeType *CT);
143 /// Get Objective-C interface type.
144 llvm::DIType *CreateType(const ObjCInterfaceType *Ty, llvm::DIFile *F);
145 llvm::DIType *CreateTypeDefinition(const ObjCInterfaceType *Ty,
147 /// Get Objective-C object type.
148 llvm::DIType *CreateType(const ObjCObjectType *Ty, llvm::DIFile *F);
149 llvm::DIType *CreateType(const VectorType *Ty, llvm::DIFile *F);
150 llvm::DIType *CreateType(const ArrayType *Ty, llvm::DIFile *F);
151 llvm::DIType *CreateType(const LValueReferenceType *Ty, llvm::DIFile *F);
152 llvm::DIType *CreateType(const RValueReferenceType *Ty, llvm::DIFile *Unit);
153 llvm::DIType *CreateType(const MemberPointerType *Ty, llvm::DIFile *F);
154 llvm::DIType *CreateType(const AtomicType *Ty, llvm::DIFile *F);
155 /// Get enumeration type.
156 llvm::DIType *CreateEnumType(const EnumType *Ty);
157 llvm::DIType *CreateTypeDefinition(const EnumType *Ty);
158 /// Look up the completed type for a self pointer in the TypeCache and
159 /// create a copy of it with the ObjectPointer and Artificial flags
160 /// set. If the type is not cached, a new one is created. This should
161 /// never happen though, since creating a type for the implicit self
162 /// argument implies that we already parsed the interface definition
163 /// and the ivar declarations in the implementation.
164 llvm::DIType *CreateSelfType(const QualType &QualTy, llvm::DIType *Ty);
167 /// Get the type from the cache or return null type if it doesn't
169 llvm::DIType *getTypeOrNull(const QualType);
170 /// Return the debug type for a C++ method.
171 /// \arg CXXMethodDecl is of FunctionType. This function type is
172 /// not updated to include implicit \c this pointer. Use this routine
173 /// to get a method type which includes \c this pointer.
174 llvm::DISubroutineType *getOrCreateMethodType(const CXXMethodDecl *Method,
176 llvm::DISubroutineType *
177 getOrCreateInstanceMethodType(QualType ThisPtr, const FunctionProtoType *Func,
179 llvm::DISubroutineType *
180 getOrCreateFunctionType(const Decl *D, QualType FnType, llvm::DIFile *F);
181 /// \return debug info descriptor for vtable.
182 llvm::DIType *getOrCreateVTablePtrType(llvm::DIFile *F);
183 /// \return namespace descriptor for the given namespace decl.
184 llvm::DINamespace *getOrCreateNameSpace(const NamespaceDecl *N);
185 llvm::DIType *getOrCreateTypeDeclaration(QualType PointeeTy, llvm::DIFile *F);
186 llvm::DIType *CreatePointerLikeType(llvm::dwarf::Tag Tag, const Type *Ty,
187 QualType PointeeTy, llvm::DIFile *F);
189 llvm::Value *getCachedInterfaceTypeOrNull(const QualType Ty);
190 llvm::DIType *getOrCreateStructPtrType(StringRef Name, llvm::DIType *&Cache);
192 /// A helper function to create a subprogram for a single member
193 /// function GlobalDecl.
194 llvm::DISubprogram *CreateCXXMemberFunction(const CXXMethodDecl *Method,
196 llvm::DIType *RecordTy);
198 /// A helper function to collect debug info for C++ member
199 /// functions. This is used while creating debug info entry for a
201 void CollectCXXMemberFunctions(const CXXRecordDecl *Decl, llvm::DIFile *F,
202 SmallVectorImpl<llvm::Metadata *> &E,
205 /// A helper function to collect debug info for C++ base
206 /// classes. This is used while creating debug info entry for a
208 void CollectCXXBases(const CXXRecordDecl *Decl, llvm::DIFile *F,
209 SmallVectorImpl<llvm::Metadata *> &EltTys,
210 llvm::DIType *RecordTy);
212 /// A helper function to collect template parameters.
213 llvm::DINodeArray CollectTemplateParams(const TemplateParameterList *TPList,
214 ArrayRef<TemplateArgument> TAList,
216 /// A helper function to collect debug info for function template
218 llvm::DINodeArray CollectFunctionTemplateParams(const FunctionDecl *FD,
221 /// A helper function to collect debug info for template
224 CollectCXXTemplateParams(const ClassTemplateSpecializationDecl *TS,
227 llvm::DIType *createFieldType(StringRef name, QualType type,
228 uint64_t sizeInBitsOverride, SourceLocation loc,
229 AccessSpecifier AS, uint64_t offsetInBits,
230 llvm::DIFile *tunit, llvm::DIScope *scope,
231 const RecordDecl *RD = nullptr);
233 /// Helpers for collecting fields of a record.
235 void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,
236 SmallVectorImpl<llvm::Metadata *> &E,
237 llvm::DIType *RecordTy);
238 llvm::DIDerivedType *CreateRecordStaticField(const VarDecl *Var,
239 llvm::DIType *RecordTy,
240 const RecordDecl *RD);
241 void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,
243 SmallVectorImpl<llvm::Metadata *> &E,
244 llvm::DIType *RecordTy, const RecordDecl *RD);
245 void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile *F,
246 SmallVectorImpl<llvm::Metadata *> &E,
247 llvm::DICompositeType *RecordTy);
249 /// If the C++ class has vtable info then insert appropriate debug
250 /// info entry in EltTys vector.
251 void CollectVTableInfo(const CXXRecordDecl *Decl, llvm::DIFile *F,
252 SmallVectorImpl<llvm::Metadata *> &EltTys);
255 /// Create a new lexical block node and push it on the stack.
256 void CreateLexicalBlock(SourceLocation Loc);
259 CGDebugInfo(CodeGenModule &CGM);
264 /// Update the current source location. If \arg loc is invalid it is
266 void setLocation(SourceLocation Loc);
268 /// Emit metadata to indicate a change in line/column information in
269 /// the source file. If the location is invalid, the previous
270 /// location will be reused.
271 void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc);
273 /// Emit a call to llvm.dbg.function.start to indicate
274 /// start of a new function.
275 /// \param Loc The location of the function header.
276 /// \param ScopeLoc The location of the function body.
277 void EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
278 SourceLocation ScopeLoc, QualType FnType,
279 llvm::Function *Fn, CGBuilderTy &Builder);
281 /// Constructs the debug code for exiting a function.
282 void EmitFunctionEnd(CGBuilderTy &Builder);
284 /// Emit metadata to indicate the beginning of a new lexical block
285 /// and push the block onto the stack.
286 void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);
288 /// Emit metadata to indicate the end of a new lexical block and pop
289 /// the current block.
290 void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);
292 /// Emit call to \c llvm.dbg.declare for an automatic variable
294 void EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,
295 CGBuilderTy &Builder);
297 /// Emit call to \c llvm.dbg.declare for an imported variable
298 /// declaration in a block.
299 void EmitDeclareOfBlockDeclRefVariable(const VarDecl *variable,
300 llvm::Value *storage,
301 CGBuilderTy &Builder,
302 const CGBlockInfo &blockInfo,
303 llvm::Instruction *InsertPoint = 0);
305 /// Emit call to \c llvm.dbg.declare for an argument variable
307 void EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI,
308 unsigned ArgNo, CGBuilderTy &Builder);
310 /// Emit call to \c llvm.dbg.declare for the block-literal argument
311 /// to a block invocation function.
312 void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
313 llvm::Value *Arg, unsigned ArgNo,
314 llvm::Value *LocalAddr,
315 CGBuilderTy &Builder);
317 /// Emit information about a global variable.
318 void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
320 /// Emit global variable's debug info.
321 void EmitGlobalVariable(const ValueDecl *VD, llvm::Constant *Init);
323 /// Emit C++ using directive.
324 void EmitUsingDirective(const UsingDirectiveDecl &UD);
326 /// Emit the type explicitly casted to.
327 void EmitExplicitCastType(QualType Ty);
329 /// Emit C++ using declaration.
330 void EmitUsingDecl(const UsingDecl &UD);
332 /// Emit an @import declaration.
333 void EmitImportDecl(const ImportDecl &ID);
335 /// Emit C++ namespace alias.
336 llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA);
338 /// Emit record type's standalone debug info.
339 llvm::DIType *getOrCreateRecordType(QualType Ty, SourceLocation L);
341 /// Emit an Objective-C interface type standalone debug info.
342 llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);
344 void completeType(const EnumDecl *ED);
345 void completeType(const RecordDecl *RD);
346 void completeRequiredType(const RecordDecl *RD);
347 void completeClassData(const RecordDecl *RD);
349 void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);
352 /// Emit call to llvm.dbg.declare for a variable declaration.
353 /// Tag accepts custom types DW_TAG_arg_variable and DW_TAG_auto_variable,
354 /// otherwise would be of type llvm::dwarf::Tag.
355 void EmitDeclare(const VarDecl *decl, llvm::dwarf::Tag Tag, llvm::Value *AI,
356 unsigned ArgNo, CGBuilderTy &Builder);
358 /// Build up structure info for the byref. See \a BuildByRefType.
359 llvm::DIType *EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
362 /// Get context info for the decl.
363 llvm::DIScope *getContextDescriptor(const Decl *Decl);
365 llvm::DIScope *getCurrentContextDescriptor(const Decl *Decl);
367 /// Create a forward decl for a RecordType in a given context.
368 llvm::DICompositeType *getOrCreateRecordFwdDecl(const RecordType *,
371 /// Return current directory name.
372 StringRef getCurrentDirname();
374 /// Create new compile unit.
375 void CreateCompileUnit();
377 /// Get the file debug info descriptor for the input location.
378 llvm::DIFile *getOrCreateFile(SourceLocation Loc);
380 /// Get the file info for main compile unit.
381 llvm::DIFile *getOrCreateMainFile();
383 /// Get the type from the cache or create a new type if necessary.
384 llvm::DIType *getOrCreateType(QualType Ty, llvm::DIFile *Fg);
386 /// Get a reference to a clang module.
388 getOrCreateModuleRef(ExternalASTSource::ASTSourceDescriptor Mod);
390 /// Get the type from the cache or create a new partial type if
392 llvm::DIType *getOrCreateLimitedType(const RecordType *Ty, llvm::DIFile *F);
394 /// Create type metadata for a source language type.
395 llvm::DIType *CreateTypeNode(QualType Ty, llvm::DIFile *Fg);
397 /// Return the underlying ObjCInterfaceDecl if \arg Ty is an
398 /// ObjCInterface or a pointer to one.
399 ObjCInterfaceDecl *getObjCInterfaceDecl(QualType Ty);
401 /// Create new member and increase Offset by FType's size.
402 llvm::DIType *CreateMemberType(llvm::DIFile *Unit, QualType FType,
403 StringRef Name, uint64_t *Offset);
405 /// Retrieve the DIDescriptor, if any, for the canonical form of this
407 llvm::DINode *getDeclarationOrDefinition(const Decl *D);
409 /// \return debug info descriptor to describe method
410 /// declaration for the given method definition.
411 llvm::DISubprogram *getFunctionDeclaration(const Decl *D);
413 /// \return debug info descriptor to describe in-class static data
414 /// member declaration for the given out-of-class definition. If D
415 /// is an out-of-class definition of a static data member of a
416 /// class, find its corresponding in-class declaration.
417 llvm::DIDerivedType *
418 getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);
420 /// Create a subprogram describing the forward declaration
421 /// represented in the given FunctionDecl.
422 llvm::DISubprogram *getFunctionForwardDeclaration(const FunctionDecl *FD);
424 /// Create a global variable describing the forward decalration
425 /// represented in the given VarDecl.
426 llvm::DIGlobalVariable *
427 getGlobalVariableForwardDeclaration(const VarDecl *VD);
429 /// \brief Return a global variable that represents one of the
430 /// collection of global variables created for an anonmyous union.
432 /// Recursively collect all of the member fields of a global
433 /// anonymous decl and create static variables for them. The first
434 /// time this is called it needs to be on a union and then from
435 /// there we can have additional unnamed fields.
436 llvm::DIGlobalVariable *
437 CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile *Unit,
438 unsigned LineNo, StringRef LinkageName,
439 llvm::GlobalVariable *Var, llvm::DIScope *DContext);
441 /// Get function name for the given FunctionDecl. If the name is
442 /// constructed on demand (e.g., C++ destructor) then the name is
443 /// stored on the side.
444 StringRef getFunctionName(const FunctionDecl *FD);
446 /// Returns the unmangled name of an Objective-C method.
447 /// This is the display name for the debugging info.
448 StringRef getObjCMethodName(const ObjCMethodDecl *FD);
450 /// Return selector name. This is used for debugging
452 StringRef getSelectorName(Selector S);
454 /// Get class name including template argument list.
455 StringRef getClassName(const RecordDecl *RD);
457 /// Get the vtable name for the given class.
458 StringRef getVTableName(const CXXRecordDecl *Decl);
460 /// Get line number for the location. If location is invalid
461 /// then use current location.
462 unsigned getLineNumber(SourceLocation Loc);
464 /// Get column number for the location. If location is
465 /// invalid then use current location.
466 /// \param Force Assume DebugColumnInfo option is true.
467 unsigned getColumnNumber(SourceLocation Loc, bool Force = false);
469 /// Collect various properties of a FunctionDecl.
470 /// \param GD A GlobalDecl whose getDecl() must return a FunctionDecl.
471 void collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
472 StringRef &Name, StringRef &LinkageName,
473 llvm::DIScope *&FDContext,
474 llvm::DINodeArray &TParamsArray,
477 /// Collect various properties of a VarDecl.
478 void collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
479 unsigned &LineNo, QualType &T, StringRef &Name,
480 StringRef &LinkageName, llvm::DIScope *&VDContext);
482 /// Allocate a copy of \p A using the DebugInfoNames allocator
483 /// and return a reference to it. If multiple arguments are given the strings
484 /// are concatenated.
485 StringRef internString(StringRef A, StringRef B = StringRef()) {
486 char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());
488 std::memcpy(Data, A.data(), A.size());
490 std::memcpy(Data + A.size(), B.data(), B.size());
491 return StringRef(Data, A.size() + B.size());
495 /// A scoped helper to set the current debug location to the specified
496 /// location or preferred location of the specified Expr.
497 class ApplyDebugLocation {
499 void init(SourceLocation TemporaryLocation, bool DefaultToEmpty = false);
500 ApplyDebugLocation(CodeGenFunction &CGF, bool DefaultToEmpty,
501 SourceLocation TemporaryLocation);
503 llvm::DebugLoc OriginalLocation;
504 CodeGenFunction &CGF;
507 /// Set the location to the (valid) TemporaryLocation.
508 ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);
509 ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);
510 ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);
512 ~ApplyDebugLocation();
514 /// \brief Apply TemporaryLocation if it is valid. Otherwise switch
515 /// to an artificial debug location that has a valid scope, but no
516 /// line information.
518 /// Artificial locations are useful when emitting compiler-generated
519 /// helper functions that have no source location associated with
520 /// them. The DWARF specification allows the compiler to use the
521 /// special line number 0 to indicate code that can not be
522 /// attributed to any source location. Note that passing an empty
523 /// SourceLocation to CGDebugInfo::setLocation() will result in the
524 /// last valid location being reused.
525 static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF) {
526 return ApplyDebugLocation(CGF, false, SourceLocation());
528 /// \brief Apply TemporaryLocation if it is valid. Otherwise switch
529 /// to an artificial debug location that has a valid scope, but no
530 /// line information.
531 static ApplyDebugLocation
532 CreateDefaultArtificial(CodeGenFunction &CGF,
533 SourceLocation TemporaryLocation) {
534 return ApplyDebugLocation(CGF, false, TemporaryLocation);
537 /// Set the IRBuilder to not attach debug locations. Note that
538 /// passing an empty SourceLocation to \a CGDebugInfo::setLocation()
539 /// will result in the last valid location being reused. Note that
540 /// all instructions that do not have a location at the beginning of
541 /// a function are counted towards to funciton prologue.
542 static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF) {
543 return ApplyDebugLocation(CGF, true, SourceLocation());
546 /// \brief Apply TemporaryLocation if it is valid. Otherwise set the IRBuilder
547 /// to not attach debug locations.
548 static ApplyDebugLocation
549 CreateDefaultEmpty(CodeGenFunction &CGF, SourceLocation TemporaryLocation) {
550 return ApplyDebugLocation(CGF, true, TemporaryLocation);
554 } // namespace CodeGen