1//===--- CGDebugInfo.h - DebugInfo for LLVM CodeGen -------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This is the source-level debug info generator for llvm translation.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef CLANG_CODEGEN_CGDEBUGINFO_H
15#define CLANG_CODEGEN_CGDEBUGINFO_H
16
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"
27
28namespace llvm {
29  class MDNode;
30}
31
32namespace clang {
33  class CXXMethodDecl;
34  class VarDecl;
35  class ObjCInterfaceDecl;
36  class ObjCIvarDecl;
37  class ClassTemplateSpecializationDecl;
38  class GlobalDecl;
39  class UsingDecl;
40
41namespace CodeGen {
42  class CodeGenModule;
43  class CodeGenFunction;
44  class CGBlockInfo;
45
46/// CGDebugInfo - This class gathers all debug information during compilation
47/// and is responsible for emitting to llvm globals or pass directly to
48/// the backend.
49class CGDebugInfo {
50  friend class ArtificialLocation;
51  friend class SaveAndRestoreLocation;
52  CodeGenModule &CGM;
53  const CodeGenOptions::DebugInfoKind DebugKind;
54  llvm::DIBuilder DBuilder;
55  llvm::DICompileUnit TheCU;
56  SourceLocation CurLoc, PrevLoc;
57  llvm::DIType VTablePtrType;
58  llvm::DIType ClassTy;
59  llvm::DICompositeType ObjTy;
60  llvm::DIType SelTy;
61  llvm::DIType OCLImage1dDITy, OCLImage1dArrayDITy, OCLImage1dBufferDITy;
62  llvm::DIType OCLImage2dDITy, OCLImage2dArrayDITy;
63  llvm::DIType OCLImage3dDITy;
64  llvm::DIType OCLEventDITy;
65  llvm::DIType BlockLiteralGeneric;
66
67  /// TypeCache - Cache of previously constructed Types.
68  llvm::DenseMap<const void *, llvm::WeakVH> TypeCache;
69
70  struct ObjCInterfaceCacheEntry {
71    const ObjCInterfaceType *Type;
72    llvm::DIType Decl;
73    llvm::DIFile Unit;
74    ObjCInterfaceCacheEntry(const ObjCInterfaceType *Type, llvm::DIType Decl,
75                            llvm::DIFile Unit)
76        : Type(Type), Decl(Decl), Unit(Unit) {}
77  };
78
79  /// ObjCInterfaceCache - Cache of previously constructed interfaces
80  /// which may change.
81  llvm::SmallVector<ObjCInterfaceCacheEntry, 32> ObjCInterfaceCache;
82
83  /// RetainedTypes - list of interfaces we want to keep even if orphaned.
84  std::vector<void *> RetainedTypes;
85
86  /// ReplaceMap - Cache of forward declared types to RAUW at the end of
87  /// compilation.
88  std::vector<std::pair<const TagType *, llvm::WeakVH>> ReplaceMap;
89
90  // LexicalBlockStack - Keep track of our current nested lexical block.
91  std::vector<llvm::TrackingVH<llvm::MDNode> > LexicalBlockStack;
92  llvm::DenseMap<const Decl *, llvm::WeakVH> RegionMap;
93  // FnBeginRegionCount - Keep track of LexicalBlockStack counter at the
94  // beginning of a function. This is used to pop unbalanced regions at
95  // the end of a function.
96  std::vector<unsigned> FnBeginRegionCount;
97
98  /// DebugInfoNames - This is a storage for names that are
99  /// constructed on demand. For example, C++ destructors, C++ operators etc..
100  llvm::BumpPtrAllocator DebugInfoNames;
101  StringRef CWDName;
102
103  llvm::DenseMap<const char *, llvm::WeakVH> DIFileCache;
104  llvm::DenseMap<const FunctionDecl *, llvm::WeakVH> SPCache;
105  /// \brief Cache declarations relevant to DW_TAG_imported_declarations (C++
106  /// using declarations) that aren't covered by other more specific caches.
107  llvm::DenseMap<const Decl *, llvm::WeakVH> DeclCache;
108  llvm::DenseMap<const NamespaceDecl *, llvm::WeakVH> NameSpaceCache;
109  llvm::DenseMap<const NamespaceAliasDecl *, llvm::WeakVH> NamespaceAliasCache;
110  llvm::DenseMap<const Decl *, llvm::WeakVH> StaticDataMemberCache;
111
112  /// Helper functions for getOrCreateType.
113  unsigned Checksum(const ObjCInterfaceDecl *InterfaceDecl);
114  llvm::DIType CreateType(const BuiltinType *Ty);
115  llvm::DIType CreateType(const ComplexType *Ty);
116  llvm::DIType CreateQualifiedType(QualType Ty, llvm::DIFile Fg);
117  llvm::DIType CreateType(const TypedefType *Ty, llvm::DIFile Fg);
118  llvm::DIType CreateType(const TemplateSpecializationType *Ty, llvm::DIFile Fg);
119  llvm::DIType CreateType(const ObjCObjectPointerType *Ty,
120                          llvm::DIFile F);
121  llvm::DIType CreateType(const PointerType *Ty, llvm::DIFile F);
122  llvm::DIType CreateType(const BlockPointerType *Ty, llvm::DIFile F);
123  llvm::DIType CreateType(const FunctionType *Ty, llvm::DIFile F);
124  llvm::DIType CreateType(const RecordType *Tyg);
125  llvm::DIType CreateTypeDefinition(const RecordType *Ty);
126  llvm::DICompositeType CreateLimitedType(const RecordType *Ty);
127  void CollectContainingType(const CXXRecordDecl *RD, llvm::DICompositeType CT);
128  llvm::DIType CreateType(const ObjCInterfaceType *Ty, llvm::DIFile F);
129  llvm::DIType CreateTypeDefinition(const ObjCInterfaceType *Ty, llvm::DIFile F);
130  llvm::DIType CreateType(const ObjCObjectType *Ty, llvm::DIFile F);
131  llvm::DIType CreateType(const VectorType *Ty, llvm::DIFile F);
132  llvm::DIType CreateType(const ArrayType *Ty, llvm::DIFile F);
133  llvm::DIType CreateType(const LValueReferenceType *Ty, llvm::DIFile F);
134  llvm::DIType CreateType(const RValueReferenceType *Ty, llvm::DIFile Unit);
135  llvm::DIType CreateType(const MemberPointerType *Ty, llvm::DIFile F);
136  llvm::DIType CreateType(const AtomicType *Ty, llvm::DIFile F);
137  llvm::DIType CreateEnumType(const EnumType *Ty);
138  llvm::DIType CreateTypeDefinition(const EnumType *Ty);
139  llvm::DIType CreateSelfType(const QualType &QualTy, llvm::DIType Ty);
140  llvm::DIType getTypeOrNull(const QualType);
141  llvm::DICompositeType getOrCreateMethodType(const CXXMethodDecl *Method,
142                                              llvm::DIFile F);
143  llvm::DICompositeType getOrCreateInstanceMethodType(
144      QualType ThisPtr, const FunctionProtoType *Func, llvm::DIFile Unit);
145  llvm::DICompositeType getOrCreateFunctionType(const Decl *D, QualType FnType,
146                                                llvm::DIFile F);
147  llvm::DIType getOrCreateVTablePtrType(llvm::DIFile F);
148  llvm::DINameSpace getOrCreateNameSpace(const NamespaceDecl *N);
149  llvm::DIType getOrCreateTypeDeclaration(QualType PointeeTy, llvm::DIFile F);
150  llvm::DIType CreatePointerLikeType(llvm::dwarf::Tag Tag,
151                                     const Type *Ty, QualType PointeeTy,
152                                     llvm::DIFile F);
153
154  llvm::Value *getCachedInterfaceTypeOrNull(const QualType Ty);
155  llvm::DIType getOrCreateStructPtrType(StringRef Name, llvm::DIType &Cache);
156
157  llvm::DISubprogram CreateCXXMemberFunction(const CXXMethodDecl *Method,
158                                             llvm::DIFile F,
159                                             llvm::DIType RecordTy);
160
161  void CollectCXXMemberFunctions(const CXXRecordDecl *Decl,
162                                 llvm::DIFile F,
163                                 SmallVectorImpl<llvm::Value *> &E,
164                                 llvm::DIType T);
165
166  void CollectCXXBases(const CXXRecordDecl *Decl,
167                       llvm::DIFile F,
168                       SmallVectorImpl<llvm::Value *> &EltTys,
169                       llvm::DIType RecordTy);
170
171  llvm::DIArray
172  CollectTemplateParams(const TemplateParameterList *TPList,
173                        ArrayRef<TemplateArgument> TAList,
174                        llvm::DIFile Unit);
175  llvm::DIArray
176  CollectFunctionTemplateParams(const FunctionDecl *FD, llvm::DIFile Unit);
177  llvm::DIArray
178  CollectCXXTemplateParams(const ClassTemplateSpecializationDecl *TS,
179                           llvm::DIFile F);
180
181  llvm::DIType createFieldType(StringRef name, QualType type,
182                               uint64_t sizeInBitsOverride, SourceLocation loc,
183                               AccessSpecifier AS, uint64_t offsetInBits,
184                               llvm::DIFile tunit,
185                               llvm::DIScope scope);
186
187  // Helpers for collecting fields of a record.
188  void CollectRecordLambdaFields(const CXXRecordDecl *CXXDecl,
189                                 SmallVectorImpl<llvm::Value *> &E,
190                                 llvm::DIType RecordTy);
191  llvm::DIDerivedType CreateRecordStaticField(const VarDecl *Var,
192                                              llvm::DIType RecordTy);
193  void CollectRecordNormalField(const FieldDecl *Field, uint64_t OffsetInBits,
194                                llvm::DIFile F,
195                                SmallVectorImpl<llvm::Value *> &E,
196                                llvm::DIType RecordTy);
197  void CollectRecordFields(const RecordDecl *Decl, llvm::DIFile F,
198                           SmallVectorImpl<llvm::Value *> &E,
199                           llvm::DICompositeType RecordTy);
200
201  void CollectVTableInfo(const CXXRecordDecl *Decl,
202                         llvm::DIFile F,
203                         SmallVectorImpl<llvm::Value *> &EltTys);
204
205  // CreateLexicalBlock - Create a new lexical block node and push it on
206  // the stack.
207  void CreateLexicalBlock(SourceLocation Loc);
208
209public:
210  CGDebugInfo(CodeGenModule &CGM);
211  ~CGDebugInfo();
212
213  void finalize();
214
215  /// setLocation - Update the current source location. If \arg loc is
216  /// invalid it is ignored.
217  void setLocation(SourceLocation Loc);
218
219  /// getLocation - Return the current source location.
220  SourceLocation getLocation() const { return CurLoc; }
221
222  /// EmitLocation - Emit metadata to indicate a change in line/column
223  /// information in the source file.
224  /// \param ForceColumnInfo  Assume DebugColumnInfo option is true.
225  void EmitLocation(CGBuilderTy &Builder, SourceLocation Loc,
226                    bool ForceColumnInfo = false);
227
228  /// EmitFunctionStart - Emit a call to llvm.dbg.function.start to indicate
229  /// start of a new function.
230  /// \param Loc       The location of the function header.
231  /// \param ScopeLoc  The location of the function body.
232  void EmitFunctionStart(GlobalDecl GD,
233                         SourceLocation Loc, SourceLocation ScopeLoc,
234                         QualType FnType, llvm::Function *Fn,
235                         CGBuilderTy &Builder);
236
237  /// EmitFunctionEnd - Constructs the debug code for exiting a function.
238  void EmitFunctionEnd(CGBuilderTy &Builder);
239
240  /// EmitLexicalBlockStart - Emit metadata to indicate the beginning of a
241  /// new lexical block and push the block onto the stack.
242  void EmitLexicalBlockStart(CGBuilderTy &Builder, SourceLocation Loc);
243
244  /// EmitLexicalBlockEnd - Emit metadata to indicate the end of a new lexical
245  /// block and pop the current block.
246  void EmitLexicalBlockEnd(CGBuilderTy &Builder, SourceLocation Loc);
247
248  /// EmitDeclareOfAutoVariable - Emit call to llvm.dbg.declare for an automatic
249  /// variable declaration.
250  void EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *AI,
251                                 CGBuilderTy &Builder);
252
253  /// EmitDeclareOfBlockDeclRefVariable - Emit call to llvm.dbg.declare for an
254  /// imported variable declaration in a block.
255  void EmitDeclareOfBlockDeclRefVariable(const VarDecl *variable,
256                                         llvm::Value *storage,
257                                         CGBuilderTy &Builder,
258                                         const CGBlockInfo &blockInfo);
259
260  /// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument
261  /// variable declaration.
262  void EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI,
263                                unsigned ArgNo, CGBuilderTy &Builder);
264
265  /// EmitDeclareOfBlockLiteralArgVariable - Emit call to
266  /// llvm.dbg.declare for the block-literal argument to a block
267  /// invocation function.
268  void EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
269                                            llvm::Value *Arg,
270                                            llvm::Value *LocalAddr,
271                                            CGBuilderTy &Builder);
272
273  /// EmitGlobalVariable - Emit information about a global variable.
274  void EmitGlobalVariable(llvm::GlobalVariable *GV, const VarDecl *Decl);
275
276  /// EmitGlobalVariable - Emit global variable's debug info.
277  void EmitGlobalVariable(const ValueDecl *VD, llvm::Constant *Init);
278
279  /// \brief - Emit C++ using directive.
280  void EmitUsingDirective(const UsingDirectiveDecl &UD);
281
282  /// \brief - Emit C++ using declaration.
283  void EmitUsingDecl(const UsingDecl &UD);
284
285  /// \brief - Emit C++ namespace alias.
286  llvm::DIImportedEntity EmitNamespaceAlias(const NamespaceAliasDecl &NA);
287
288  /// getOrCreateRecordType - Emit record type's standalone debug info.
289  llvm::DIType getOrCreateRecordType(QualType Ty, SourceLocation L);
290
291  /// getOrCreateInterfaceType - Emit an objective c interface type standalone
292  /// debug info.
293  llvm::DIType getOrCreateInterfaceType(QualType Ty,
294                                        SourceLocation Loc);
295
296  void completeType(const EnumDecl *ED);
297  void completeType(const RecordDecl *RD);
298  void completeRequiredType(const RecordDecl *RD);
299  void completeClassData(const RecordDecl *RD);
300
301  void completeTemplateDefinition(const ClassTemplateSpecializationDecl &SD);
302
303private:
304  /// EmitDeclare - Emit call to llvm.dbg.declare for a variable declaration.
305  /// Tag accepts custom types DW_TAG_arg_variable and DW_TAG_auto_variable,
306  /// otherwise would be of type llvm::dwarf::Tag.
307  void EmitDeclare(const VarDecl *decl, llvm::dwarf::LLVMConstants Tag,
308                   llvm::Value *AI, unsigned ArgNo, CGBuilderTy &Builder);
309
310  // EmitTypeForVarWithBlocksAttr - Build up structure info for the byref.
311  // See BuildByRefType.
312  llvm::DIType EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
313                                            uint64_t *OffSet);
314
315  /// getContextDescriptor - Get context info for the decl.
316  llvm::DIScope getContextDescriptor(const Decl *Decl);
317
318  llvm::DIScope getCurrentContextDescriptor(const Decl *Decl);
319
320  /// \brief Create a forward decl for a RecordType in a given context.
321  llvm::DICompositeType getOrCreateRecordFwdDecl(const RecordType *,
322                                                 llvm::DIDescriptor);
323
324  /// createContextChain - Create a set of decls for the context chain.
325  llvm::DIDescriptor createContextChain(const Decl *Decl);
326
327  /// getCurrentDirname - Return current directory name.
328  StringRef getCurrentDirname();
329
330  /// CreateCompileUnit - Create new compile unit.
331  void CreateCompileUnit();
332
333  /// getOrCreateFile - Get the file debug info descriptor for the input
334  /// location.
335  llvm::DIFile getOrCreateFile(SourceLocation Loc);
336
337  /// getOrCreateMainFile - Get the file info for main compile unit.
338  llvm::DIFile getOrCreateMainFile();
339
340  /// getOrCreateType - Get the type from the cache or create a new type if
341  /// necessary.
342  llvm::DIType getOrCreateType(QualType Ty, llvm::DIFile Fg);
343
344  /// getOrCreateLimitedType - Get the type from the cache or create a new
345  /// partial type if necessary.
346  llvm::DIType getOrCreateLimitedType(const RecordType *Ty, llvm::DIFile F);
347
348  /// CreateTypeNode - Create type metadata for a source language type.
349  llvm::DIType CreateTypeNode(QualType Ty, llvm::DIFile Fg);
350
351  /// getObjCInterfaceDecl - return the underlying ObjCInterfaceDecl
352  /// if Ty is an ObjCInterface or a pointer to one.
353  ObjCInterfaceDecl* getObjCInterfaceDecl(QualType Ty);
354
355  /// CreateMemberType - Create new member and increase Offset by FType's size.
356  llvm::DIType CreateMemberType(llvm::DIFile Unit, QualType FType,
357                                StringRef Name, uint64_t *Offset);
358
359  /// \brief Retrieve the DIScope, if any, for the canonical form of this
360  /// declaration.
361  llvm::DIScope getDeclarationOrDefinition(const Decl *D);
362
363  /// getFunctionDeclaration - Return debug info descriptor to describe method
364  /// declaration for the given method definition.
365  llvm::DISubprogram getFunctionDeclaration(const Decl *D);
366
367  /// Return debug info descriptor to describe in-class static data member
368  /// declaration for the given out-of-class definition.
369  llvm::DIDerivedType
370  getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D);
371
372  /// Return a global variable that represents one of the collection of
373  /// global variables created for an anonmyous union.
374  llvm::DIGlobalVariable
375  CollectAnonRecordDecls(const RecordDecl *RD, llvm::DIFile Unit, unsigned LineNo,
376                         StringRef LinkageName, llvm::GlobalVariable *Var,
377                         llvm::DIDescriptor DContext);
378
379  /// getFunctionName - Get function name for the given FunctionDecl. If the
380  /// name is constructed on demand (e.g. C++ destructor) then the name
381  /// is stored on the side.
382  StringRef getFunctionName(const FunctionDecl *FD);
383
384  /// getObjCMethodName - Returns the unmangled name of an Objective-C method.
385  /// This is the display name for the debugging info.
386  StringRef getObjCMethodName(const ObjCMethodDecl *FD);
387
388  /// getSelectorName - Return selector name. This is used for debugging
389  /// info.
390  StringRef getSelectorName(Selector S);
391
392  /// getClassName - Get class name including template argument list.
393  StringRef getClassName(const RecordDecl *RD);
394
395  /// getVTableName - Get vtable name for the given Class.
396  StringRef getVTableName(const CXXRecordDecl *Decl);
397
398  /// getLineNumber - Get line number for the location. If location is invalid
399  /// then use current location.
400  unsigned getLineNumber(SourceLocation Loc);
401
402  /// getColumnNumber - Get column number for the location. If location is
403  /// invalid then use current location.
404  /// \param Force  Assume DebugColumnInfo option is true.
405  unsigned getColumnNumber(SourceLocation Loc, bool Force=false);
406
407  /// internString - Allocate a copy of \p A using the DebugInfoNames allocator
408  /// and return a reference to it. If multiple arguments are given the strings
409  /// are concatenated.
410  StringRef internString(StringRef A, StringRef B = StringRef()) {
411    char *Data = DebugInfoNames.Allocate<char>(A.size() + B.size());
412    std::memcpy(Data, A.data(), A.size());
413    std::memcpy(Data + A.size(), B.data(), B.size());
414    return StringRef(Data, A.size() + B.size());
415  }
416};
417
418/// SaveAndRestoreLocation - An RAII object saves the current location
419/// and automatically restores it to the original value.
420class SaveAndRestoreLocation {
421protected:
422  SourceLocation SavedLoc;
423  CGDebugInfo *DI;
424  CGBuilderTy &Builder;
425public:
426  SaveAndRestoreLocation(CodeGenFunction &CGF, CGBuilderTy &B);
427  /// Autorestore everything back to normal.
428  ~SaveAndRestoreLocation();
429};
430
431/// NoLocation - An RAII object that temporarily disables debug
432/// locations. This is useful for emitting instructions that should be
433/// counted towards the function prologue.
434class NoLocation : public SaveAndRestoreLocation {
435public:
436  NoLocation(CodeGenFunction &CGF, CGBuilderTy &B);
437  /// Autorestore everything back to normal.
438  ~NoLocation();
439};
440
441/// ArtificialLocation - An RAII object that temporarily switches to
442/// an artificial debug location that has a valid scope, but no line
443/// information. This is useful when emitting compiler-generated
444/// helper functions that have no source location associated with
445/// them. The DWARF specification allows the compiler to use the
446/// special line number 0 to indicate code that can not be attributed
447/// to any source location.
448///
449/// This is necessary because passing an empty SourceLocation to
450/// CGDebugInfo::setLocation() will result in the last valid location
451/// being reused.
452class ArtificialLocation : public SaveAndRestoreLocation {
453public:
454  ArtificialLocation(CodeGenFunction &CGF, CGBuilderTy &B);
455
456  /// Set the current location to line 0, but within the current scope
457  /// (= the top of the LexicalBlockStack).
458  void Emit();
459
460  /// Autorestore everything back to normal.
461  ~ArtificialLocation();
462};
463
464
465} // namespace CodeGen
466} // namespace clang
467
468
469#endif
470