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