CGDebugInfo.cpp revision d3651cc24fbcffd8f187c82e6a91e6e3de7fe26e 
1//===--- CGDebugInfo.cpp - Emit Debug Information for a Module ------------===//
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 coordinates the debug information generation while generating code.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CGDebugInfo.h"
15#include "CodeGenFunction.h"
16#include "CodeGenModule.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/DeclObjC.h"
19#include "clang/AST/Expr.h"
20#include "clang/AST/RecordLayout.h"
21#include "clang/Basic/SourceManager.h"
22#include "clang/Basic/FileManager.h"
23#include "clang/Basic/Version.h"
24#include "clang/CodeGen/CodeGenOptions.h"
25#include "llvm/Constants.h"
26#include "llvm/DerivedTypes.h"
27#include "llvm/Instructions.h"
28#include "llvm/Intrinsics.h"
29#include "llvm/Module.h"
30#include "llvm/ADT/StringExtras.h"
31#include "llvm/ADT/SmallVector.h"
32#include "llvm/Support/Dwarf.h"
33#include "llvm/System/Path.h"
34#include "llvm/Target/TargetMachine.h"
35using namespace clang;
36using namespace clang::CodeGen;
37
38CGDebugInfo::CGDebugInfo(CodeGenModule &CGM)
39  : CGM(CGM), DebugFactory(CGM.getModule()),
40    FwdDeclCount(0), BlockLiteralGenericSet(false) {
41  CreateCompileUnit();
42}
43
44CGDebugInfo::~CGDebugInfo() {
45  assert(RegionStack.empty() && "Region stack mismatch, stack not empty!");
46}
47
48void CGDebugInfo::setLocation(SourceLocation Loc) {
49  if (Loc.isValid())
50    CurLoc = CGM.getContext().getSourceManager().getInstantiationLoc(Loc);
51}
52
53/// getContextDescriptor - Get context info for the decl.
54llvm::DIDescriptor CGDebugInfo::getContextDescriptor(const Decl *Context,
55                                              llvm::DIDescriptor &CompileUnit) {
56  if (!Context)
57    return CompileUnit;
58
59  llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator
60    I = RegionMap.find(Context);
61  if (I != RegionMap.end())
62    return llvm::DIDescriptor(dyn_cast_or_null<llvm::MDNode>(I->second));
63
64  // Check namespace.
65  if (const NamespaceDecl *NSDecl = dyn_cast<NamespaceDecl>(Context))
66    return llvm::DIDescriptor(getOrCreateNameSpace(NSDecl, CompileUnit));
67
68  return CompileUnit;
69}
70
71/// getFunctionName - Get function name for the given FunctionDecl. If the
72/// name is constructred on demand (e.g. C++ destructor) then the name
73/// is stored on the side.
74llvm::StringRef CGDebugInfo::getFunctionName(const FunctionDecl *FD) {
75  assert (FD && "Invalid FunctionDecl!");
76  IdentifierInfo *FII = FD->getIdentifier();
77  if (FII)
78    return FII->getName();
79
80  // Otherwise construct human readable name for debug info.
81  std::string NS = FD->getNameAsString();
82
83  // Copy this name on the side and use its reference.
84  char *StrPtr = DebugInfoNames.Allocate<char>(NS.length());
85  memcpy(StrPtr, NS.data(), NS.length());
86  return llvm::StringRef(StrPtr, NS.length());
87}
88
89/// getOrCreateFile - Get the file debug info descriptor for the input location.
90llvm::DIFile CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
91  if (!Loc.isValid())
92    // If Location is not valid then use main input file.
93    return DebugFactory.CreateFile(TheCU.getFilename(), TheCU.getDirectory(),
94                                   TheCU);
95  SourceManager &SM = CGM.getContext().getSourceManager();
96  PresumedLoc PLoc = SM.getPresumedLoc(Loc);
97
98  // Cache the results.
99  const char *fname = PLoc.getFilename();
100  llvm::DenseMap<const char *, llvm::WeakVH>::iterator it =
101    DIFileCache.find(fname);
102
103  if (it != DIFileCache.end()) {
104    // Verify that the information still exists.
105    if (&*it->second)
106      return llvm::DIFile(cast<llvm::MDNode>(it->second));
107  }
108
109  // FIXME: We shouldn't even need to call 'makeAbsolute()' in the cases
110  // where we can consult the FileEntry.
111  llvm::sys::Path AbsFileName(PLoc.getFilename());
112  AbsFileName.makeAbsolute();
113
114  llvm::DIFile F = DebugFactory.CreateFile(AbsFileName.getLast(),
115                                           AbsFileName.getDirname(), TheCU);
116
117  DIFileCache[fname] = F.getNode();
118  return F;
119
120}
121/// CreateCompileUnit - Create new compile unit.
122void CGDebugInfo::CreateCompileUnit() {
123
124  // Get absolute path name.
125  SourceManager &SM = CGM.getContext().getSourceManager();
126  std::string MainFileName = CGM.getCodeGenOpts().MainFileName;
127  if (MainFileName.empty())
128    MainFileName = "<unknown>";
129
130  llvm::sys::Path AbsFileName(MainFileName);
131  AbsFileName.makeAbsolute();
132
133  // The main file name provided via the "-main-file-name" option contains just
134  // the file name itself with no path information. This file name may have had
135  // a relative path, so we look into the actual file entry for the main
136  // file to determine the real absolute path for the file.
137  std::string MainFileDir;
138  if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID()))
139    MainFileDir = MainFile->getDir()->getName();
140  else
141    MainFileDir = AbsFileName.getDirname();
142
143  unsigned LangTag;
144  const LangOptions &LO = CGM.getLangOptions();
145  if (LO.CPlusPlus) {
146    if (LO.ObjC1)
147      LangTag = llvm::dwarf::DW_LANG_ObjC_plus_plus;
148    else
149      LangTag = llvm::dwarf::DW_LANG_C_plus_plus;
150  } else if (LO.ObjC1) {
151    LangTag = llvm::dwarf::DW_LANG_ObjC;
152  } else if (LO.C99) {
153    LangTag = llvm::dwarf::DW_LANG_C99;
154  } else {
155    LangTag = llvm::dwarf::DW_LANG_C89;
156  }
157
158  const char *Producer =
159#ifdef CLANG_VENDOR
160    CLANG_VENDOR
161#endif
162    "clang " CLANG_VERSION_STRING;
163
164  // Figure out which version of the ObjC runtime we have.
165  unsigned RuntimeVers = 0;
166  if (LO.ObjC1)
167    RuntimeVers = LO.ObjCNonFragileABI ? 2 : 1;
168
169  // Create new compile unit.
170  TheCU = DebugFactory.CreateCompileUnit(
171    LangTag, AbsFileName.getLast(), MainFileDir, Producer, true,
172    LO.Optimize, CGM.getCodeGenOpts().DwarfDebugFlags, RuntimeVers);
173}
174
175/// CreateType - Get the Basic type from the cache or create a new
176/// one if necessary.
177llvm::DIType CGDebugInfo::CreateType(const BuiltinType *BT,
178                                     llvm::DIFile Unit) {
179  unsigned Encoding = 0;
180  switch (BT->getKind()) {
181  default:
182  case BuiltinType::Void:
183    return llvm::DIType();
184  case BuiltinType::UChar:
185  case BuiltinType::Char_U: Encoding = llvm::dwarf::DW_ATE_unsigned_char; break;
186  case BuiltinType::Char_S:
187  case BuiltinType::SChar: Encoding = llvm::dwarf::DW_ATE_signed_char; break;
188  case BuiltinType::UShort:
189  case BuiltinType::UInt:
190  case BuiltinType::ULong:
191  case BuiltinType::ULongLong: Encoding = llvm::dwarf::DW_ATE_unsigned; break;
192  case BuiltinType::Short:
193  case BuiltinType::Int:
194  case BuiltinType::Long:
195  case BuiltinType::LongLong:  Encoding = llvm::dwarf::DW_ATE_signed; break;
196  case BuiltinType::Bool:      Encoding = llvm::dwarf::DW_ATE_boolean; break;
197  case BuiltinType::Float:
198  case BuiltinType::LongDouble:
199  case BuiltinType::Double:    Encoding = llvm::dwarf::DW_ATE_float; break;
200  }
201  // Bit size, align and offset of the type.
202  uint64_t Size = CGM.getContext().getTypeSize(BT);
203  uint64_t Align = CGM.getContext().getTypeAlign(BT);
204  uint64_t Offset = 0;
205
206  llvm::DIType DbgTy =
207    DebugFactory.CreateBasicType(Unit,
208                                 BT->getName(CGM.getContext().getLangOptions()),
209                                 Unit, 0, Size, Align,
210                                 Offset, /*flags*/ 0, Encoding);
211  return DbgTy;
212}
213
214llvm::DIType CGDebugInfo::CreateType(const ComplexType *Ty,
215                                     llvm::DIFile Unit) {
216  // Bit size, align and offset of the type.
217  unsigned Encoding = llvm::dwarf::DW_ATE_complex_float;
218  if (Ty->isComplexIntegerType())
219    Encoding = llvm::dwarf::DW_ATE_lo_user;
220
221  uint64_t Size = CGM.getContext().getTypeSize(Ty);
222  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
223  uint64_t Offset = 0;
224
225  llvm::DIType DbgTy =
226    DebugFactory.CreateBasicType(Unit, "complex",
227                                 Unit, 0, Size, Align,
228                                 Offset, /*flags*/ 0, Encoding);
229  return DbgTy;
230}
231
232/// CreateCVRType - Get the qualified type from the cache or create
233/// a new one if necessary.
234llvm::DIType CGDebugInfo::CreateQualifiedType(QualType Ty, llvm::DIFile Unit) {
235  QualifierCollector Qc;
236  const Type *T = Qc.strip(Ty);
237
238  // Ignore these qualifiers for now.
239  Qc.removeObjCGCAttr();
240  Qc.removeAddressSpace();
241
242  // We will create one Derived type for one qualifier and recurse to handle any
243  // additional ones.
244  unsigned Tag;
245  if (Qc.hasConst()) {
246    Tag = llvm::dwarf::DW_TAG_const_type;
247    Qc.removeConst();
248  } else if (Qc.hasVolatile()) {
249    Tag = llvm::dwarf::DW_TAG_volatile_type;
250    Qc.removeVolatile();
251  } else if (Qc.hasRestrict()) {
252    Tag = llvm::dwarf::DW_TAG_restrict_type;
253    Qc.removeRestrict();
254  } else {
255    assert(Qc.empty() && "Unknown type qualifier for debug info");
256    return getOrCreateType(QualType(T, 0), Unit);
257  }
258
259  llvm::DIType FromTy = getOrCreateType(Qc.apply(T), Unit);
260
261  // No need to fill in the Name, Line, Size, Alignment, Offset in case of
262  // CVR derived types.
263  llvm::DIType DbgTy =
264    DebugFactory.CreateDerivedType(Tag, Unit, "", Unit,
265                                   0, 0, 0, 0, 0, FromTy);
266  return DbgTy;
267}
268
269llvm::DIType CGDebugInfo::CreateType(const ObjCObjectPointerType *Ty,
270                                     llvm::DIFile Unit) {
271  llvm::DIType DbgTy =
272    CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
273                          Ty->getPointeeType(), Unit);
274  return DbgTy;
275}
276
277llvm::DIType CGDebugInfo::CreateType(const PointerType *Ty,
278                                     llvm::DIFile Unit) {
279  return CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
280                               Ty->getPointeeType(), Unit);
281}
282
283llvm::DIType CGDebugInfo::CreatePointerLikeType(unsigned Tag,
284                                                const Type *Ty,
285                                                QualType PointeeTy,
286                                                llvm::DIFile Unit) {
287  llvm::DIType EltTy = getOrCreateType(PointeeTy, Unit);
288
289  // Bit size, align and offset of the type.
290
291  // Size is always the size of a pointer. We can't use getTypeSize here
292  // because that does not return the correct value for references.
293  uint64_t Size =
294    CGM.getContext().Target.getPointerWidth(PointeeTy.getAddressSpace());
295  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
296
297  return
298    DebugFactory.CreateDerivedType(Tag, Unit, "", Unit,
299                                   0, Size, Align, 0, 0, EltTy);
300
301}
302
303llvm::DIType CGDebugInfo::CreateType(const BlockPointerType *Ty,
304                                     llvm::DIFile Unit) {
305  if (BlockLiteralGenericSet)
306    return BlockLiteralGeneric;
307
308  unsigned Tag = llvm::dwarf::DW_TAG_structure_type;
309
310  llvm::SmallVector<llvm::DIDescriptor, 5> EltTys;
311
312  llvm::DIType FieldTy;
313
314  QualType FType;
315  uint64_t FieldSize, FieldOffset;
316  unsigned FieldAlign;
317
318  llvm::DIArray Elements;
319  llvm::DIType EltTy, DescTy;
320
321  FieldOffset = 0;
322  FType = CGM.getContext().UnsignedLongTy;
323  EltTys.push_back(CreateMemberType(Unit, FType, "reserved", &FieldOffset));
324  EltTys.push_back(CreateMemberType(Unit, FType, "Size", &FieldOffset));
325
326  Elements = DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
327  EltTys.clear();
328
329  unsigned Flags = llvm::DIType::FlagAppleBlock;
330
331  EltTy = DebugFactory.CreateCompositeType(Tag, Unit, "__block_descriptor",
332                                           Unit, 0, FieldOffset, 0, 0, Flags,
333                                           llvm::DIType(), Elements);
334
335  // Bit size, align and offset of the type.
336  uint64_t Size = CGM.getContext().getTypeSize(Ty);
337  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
338
339  DescTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type,
340                                          Unit, "", Unit,
341                                          0, Size, Align, 0, 0, EltTy);
342
343  FieldOffset = 0;
344  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
345  EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
346  FType = CGM.getContext().IntTy;
347  EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
348  EltTys.push_back(CreateMemberType(Unit, FType, "__reserved", &FieldOffset));
349  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
350  EltTys.push_back(CreateMemberType(Unit, FType, "__FuncPtr", &FieldOffset));
351
352  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
353  FieldTy = DescTy;
354  FieldSize = CGM.getContext().getTypeSize(Ty);
355  FieldAlign = CGM.getContext().getTypeAlign(Ty);
356  FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
357                                           "__descriptor", Unit,
358                                           0, FieldSize, FieldAlign,
359                                           FieldOffset, 0, FieldTy);
360  EltTys.push_back(FieldTy);
361
362  FieldOffset += FieldSize;
363  Elements = DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
364
365  EltTy = DebugFactory.CreateCompositeType(Tag, Unit, "__block_literal_generic",
366                                           Unit, 0, FieldOffset, 0, 0, Flags,
367                                           llvm::DIType(), Elements);
368
369  BlockLiteralGenericSet = true;
370  BlockLiteralGeneric
371    = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type, Unit,
372                                     "", Unit,
373                                     0, Size, Align, 0, 0, EltTy);
374  return BlockLiteralGeneric;
375}
376
377llvm::DIType CGDebugInfo::CreateType(const TypedefType *Ty,
378                                     llvm::DIFile Unit) {
379  // Typedefs are derived from some other type.  If we have a typedef of a
380  // typedef, make sure to emit the whole chain.
381  llvm::DIType Src = getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
382
383  // We don't set size information, but do specify where the typedef was
384  // declared.
385  SourceManager &SM = CGM.getContext().getSourceManager();
386  PresumedLoc PLoc = SM.getPresumedLoc(Ty->getDecl()->getLocation());
387  unsigned Line = PLoc.isInvalid() ? 0 : PLoc.getLine();
388
389  llvm::DIDescriptor TyContext
390    = getContextDescriptor(dyn_cast<Decl>(Ty->getDecl()->getDeclContext()),
391                           Unit);
392  llvm::DIType DbgTy =
393    DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_typedef,
394                                   TyContext,
395                                   Ty->getDecl()->getName(), Unit,
396                                   Line, 0, 0, 0, 0, Src);
397  return DbgTy;
398}
399
400llvm::DIType CGDebugInfo::CreateType(const FunctionType *Ty,
401                                     llvm::DIFile Unit) {
402  llvm::SmallVector<llvm::DIDescriptor, 16> EltTys;
403
404  // Add the result type at least.
405  EltTys.push_back(getOrCreateType(Ty->getResultType(), Unit));
406
407  // Set up remainder of arguments if there is a prototype.
408  // FIXME: IF NOT, HOW IS THIS REPRESENTED?  llvm-gcc doesn't represent '...'!
409  if (const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(Ty)) {
410    for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
411      EltTys.push_back(getOrCreateType(FTP->getArgType(i), Unit));
412  } else {
413    // FIXME: Handle () case in C.  llvm-gcc doesn't do it either.
414  }
415
416  llvm::DIArray EltTypeArray =
417    DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
418
419  llvm::DIType DbgTy =
420    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_subroutine_type,
421                                     Unit, "", Unit,
422                                     0, 0, 0, 0, 0,
423                                     llvm::DIType(), EltTypeArray);
424  return DbgTy;
425}
426
427/// CollectRecordFields - A helper function to collect debug info for
428/// record fields. This is used while creating debug info entry for a Record.
429void CGDebugInfo::
430CollectRecordFields(const RecordDecl *RD, llvm::DIFile Unit,
431                    llvm::SmallVectorImpl<llvm::DIDescriptor> &EltTys) {
432  unsigned FieldNo = 0;
433  SourceManager &SM = CGM.getContext().getSourceManager();
434  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
435  for (RecordDecl::field_iterator I = RD->field_begin(),
436                                  E = RD->field_end();
437       I != E; ++I, ++FieldNo) {
438    FieldDecl *Field = *I;
439    llvm::DIType FieldTy = getOrCreateType(Field->getType(), Unit);
440
441    llvm::StringRef FieldName = Field->getName();
442
443    // Ignore unnamed fields. Do not ignore unnamed records.
444    if (FieldName.empty() && !isa<RecordType>(Field->getType()))
445      continue;
446
447    // Get the location for the field.
448    SourceLocation FieldDefLoc = Field->getLocation();
449    PresumedLoc PLoc = SM.getPresumedLoc(FieldDefLoc);
450    llvm::DIFile FieldDefUnit;
451    unsigned FieldLine = 0;
452
453    if (!PLoc.isInvalid()) {
454      FieldDefUnit = getOrCreateFile(FieldDefLoc);
455      FieldLine = PLoc.getLine();
456    }
457
458    QualType FType = Field->getType();
459    uint64_t FieldSize = 0;
460    unsigned FieldAlign = 0;
461    if (!FType->isIncompleteArrayType()) {
462
463      // Bit size, align and offset of the type.
464      FieldSize = CGM.getContext().getTypeSize(FType);
465      Expr *BitWidth = Field->getBitWidth();
466      if (BitWidth)
467        FieldSize = BitWidth->EvaluateAsInt(CGM.getContext()).getZExtValue();
468
469      FieldAlign =  CGM.getContext().getTypeAlign(FType);
470    }
471
472    uint64_t FieldOffset = RL.getFieldOffset(FieldNo);
473
474    unsigned Flags = 0;
475    AccessSpecifier Access = I->getAccess();
476    if (Access == clang::AS_private)
477      Flags |= llvm::DIType::FlagPrivate;
478    else if (Access == clang::AS_protected)
479      Flags |= llvm::DIType::FlagProtected;
480
481    // Create a DW_TAG_member node to remember the offset of this field in the
482    // struct.  FIXME: This is an absolutely insane way to capture this
483    // information.  When we gut debug info, this should be fixed.
484    FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
485                                             FieldName, FieldDefUnit,
486                                             FieldLine, FieldSize, FieldAlign,
487                                             FieldOffset, Flags, FieldTy);
488    EltTys.push_back(FieldTy);
489  }
490}
491
492/// getOrCreateMethodType - CXXMethodDecl's type is a FunctionType. This
493/// function type is not updated to include implicit "this" pointer. Use this
494/// routine to get a method type which includes "this" pointer.
495llvm::DIType
496CGDebugInfo::getOrCreateMethodType(const CXXMethodDecl *Method,
497                                   llvm::DIFile Unit) {
498  llvm::DIType FnTy = getOrCreateType(Method->getType(), Unit);
499
500  // Static methods do not need "this" pointer argument.
501  if (Method->isStatic())
502    return FnTy;
503
504  // Add "this" pointer.
505
506  llvm::DIArray Args = llvm::DICompositeType(FnTy.getNode()).getTypeArray();
507  assert (Args.getNumElements() && "Invalid number of arguments!");
508
509  llvm::SmallVector<llvm::DIDescriptor, 16> Elts;
510
511  // First element is always return type. For 'void' functions it is NULL.
512  Elts.push_back(Args.getElement(0));
513
514  // "this" pointer is always first argument.
515  ASTContext &Context = CGM.getContext();
516  QualType ThisPtr =
517    Context.getPointerType(Context.getTagDeclType(Method->getParent()));
518  llvm::DIType ThisPtrType =
519    DebugFactory.CreateArtificialType(getOrCreateType(ThisPtr, Unit));
520  TypeCache[ThisPtr.getAsOpaquePtr()] = ThisPtrType.getNode();
521  Elts.push_back(ThisPtrType);
522
523  // Copy rest of the arguments.
524  for (unsigned i = 1, e = Args.getNumElements(); i != e; ++i)
525    Elts.push_back(Args.getElement(i));
526
527  llvm::DIArray EltTypeArray =
528    DebugFactory.GetOrCreateArray(Elts.data(), Elts.size());
529
530  return
531    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_subroutine_type,
532                                     Unit, "", Unit,
533                                     0, 0, 0, 0, 0,
534                                     llvm::DIType(), EltTypeArray);
535}
536
537/// CreateCXXMemberFunction - A helper function to create a DISubprogram for
538/// a single member function GlobalDecl.
539llvm::DISubprogram
540CGDebugInfo::CreateCXXMemberFunction(const CXXMethodDecl *Method,
541                                     llvm::DIFile Unit,
542                                     llvm::DICompositeType &RecordTy) {
543  bool IsCtorOrDtor =
544    isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method);
545
546  llvm::StringRef MethodName = getFunctionName(Method);
547  llvm::DIType MethodTy = getOrCreateMethodType(Method, Unit);
548
549  // Since a single ctor/dtor corresponds to multiple functions, it doesn't
550  // make sense to give a single ctor/dtor a linkage name.
551  MangleBuffer MethodLinkageName;
552  if (!IsCtorOrDtor)
553    CGM.getMangledName(MethodLinkageName, Method);
554
555  SourceManager &SM = CGM.getContext().getSourceManager();
556
557  // Get the location for the method.
558  SourceLocation MethodDefLoc = Method->getLocation();
559  PresumedLoc PLoc = SM.getPresumedLoc(MethodDefLoc);
560  llvm::DIFile MethodDefUnit;
561  unsigned MethodLine = 0;
562
563  if (!PLoc.isInvalid()) {
564    MethodDefUnit = getOrCreateFile(MethodDefLoc);
565    MethodLine = PLoc.getLine();
566  }
567
568  // Collect virtual method info.
569  llvm::DIType ContainingType;
570  unsigned Virtuality = 0;
571  unsigned VIndex = 0;
572
573  if (Method->isVirtual()) {
574    if (Method->isPure())
575      Virtuality = llvm::dwarf::DW_VIRTUALITY_pure_virtual;
576    else
577      Virtuality = llvm::dwarf::DW_VIRTUALITY_virtual;
578
579    // It doesn't make sense to give a virtual destructor a vtable index,
580    // since a single destructor has two entries in the vtable.
581    if (!isa<CXXDestructorDecl>(Method))
582      VIndex = CGM.getVTables().getMethodVTableIndex(Method);
583    ContainingType = RecordTy;
584  }
585
586  llvm::DISubprogram SP =
587    DebugFactory.CreateSubprogram(RecordTy , MethodName, MethodName,
588                                  MethodLinkageName,
589                                  MethodDefUnit, MethodLine,
590                                  MethodTy, /*isLocalToUnit=*/false,
591                                  Method->isThisDeclarationADefinition(),
592                                  Virtuality, VIndex, ContainingType);
593
594  // Don't cache ctors or dtors since we have to emit multiple functions for
595  // a single ctor or dtor.
596  if (!IsCtorOrDtor && Method->isThisDeclarationADefinition())
597    SPCache[Method] = llvm::WeakVH(SP.getNode());
598
599  return SP;
600}
601
602/// CollectCXXMemberFunctions - A helper function to collect debug info for
603/// C++ member functions.This is used while creating debug info entry for
604/// a Record.
605void CGDebugInfo::
606CollectCXXMemberFunctions(const CXXRecordDecl *RD, llvm::DIFile Unit,
607                          llvm::SmallVectorImpl<llvm::DIDescriptor> &EltTys,
608                          llvm::DICompositeType &RecordTy) {
609  for(CXXRecordDecl::method_iterator I = RD->method_begin(),
610        E = RD->method_end(); I != E; ++I) {
611    const CXXMethodDecl *Method = *I;
612
613    if (Method->isImplicit() && !Method->isUsed())
614      continue;
615
616    EltTys.push_back(CreateCXXMemberFunction(Method, Unit, RecordTy));
617  }
618}
619
620/// CollectCXXBases - A helper function to collect debug info for
621/// C++ base classes. This is used while creating debug info entry for
622/// a Record.
623void CGDebugInfo::
624CollectCXXBases(const CXXRecordDecl *RD, llvm::DIFile Unit,
625                llvm::SmallVectorImpl<llvm::DIDescriptor> &EltTys,
626                llvm::DICompositeType &RecordTy) {
627
628  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
629  for (CXXRecordDecl::base_class_const_iterator BI = RD->bases_begin(),
630         BE = RD->bases_end(); BI != BE; ++BI) {
631    unsigned BFlags = 0;
632    uint64_t BaseOffset;
633
634    const CXXRecordDecl *Base =
635      cast<CXXRecordDecl>(BI->getType()->getAs<RecordType>()->getDecl());
636
637    if (BI->isVirtual()) {
638      // virtual base offset offset is -ve. The code generator emits dwarf
639      // expression where it expects +ve number.
640      BaseOffset = 0 - CGM.getVTables().getVirtualBaseOffsetOffset(RD, Base);
641      BFlags = llvm::DIType::FlagVirtual;
642    } else
643      BaseOffset = RL.getBaseClassOffset(Base);
644
645    AccessSpecifier Access = BI->getAccessSpecifier();
646    if (Access == clang::AS_private)
647      BFlags |= llvm::DIType::FlagPrivate;
648    else if (Access == clang::AS_protected)
649      BFlags |= llvm::DIType::FlagProtected;
650
651    llvm::DIType DTy =
652      DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_inheritance,
653                                     RecordTy, llvm::StringRef(),
654                                     Unit, 0, 0, 0,
655                                     BaseOffset, BFlags,
656                                     getOrCreateType(BI->getType(),
657                                                     Unit));
658    EltTys.push_back(DTy);
659  }
660}
661
662/// getOrCreateVTablePtrType - Return debug info descriptor for vtable.
663llvm::DIType CGDebugInfo::getOrCreateVTablePtrType(llvm::DIFile Unit) {
664  if (VTablePtrType.isValid())
665    return VTablePtrType;
666
667  ASTContext &Context = CGM.getContext();
668
669  /* Function type */
670  llvm::DIDescriptor STy = getOrCreateType(Context.IntTy, Unit);
671  llvm::DIArray SElements = DebugFactory.GetOrCreateArray(&STy, 1);
672  llvm::DIType SubTy =
673    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_subroutine_type,
674                                     Unit, "", Unit,
675                                     0, 0, 0, 0, 0, llvm::DIType(), SElements);
676
677  unsigned Size = Context.getTypeSize(Context.VoidPtrTy);
678  llvm::DIType vtbl_ptr_type
679    = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type,
680                                     Unit, "__vtbl_ptr_type", Unit,
681                                     0, Size, 0, 0, 0, SubTy);
682
683  VTablePtrType =
684    DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type,
685                                   Unit, "", Unit,
686                                   0, Size, 0, 0, 0, vtbl_ptr_type);
687  return VTablePtrType;
688}
689
690/// getVTableName - Get vtable name for the given Class.
691llvm::StringRef CGDebugInfo::getVTableName(const CXXRecordDecl *RD) {
692  // Otherwise construct gdb compatible name name.
693  std::string Name = "_vptr$" + RD->getNameAsString();
694
695  // Copy this name on the side and use its reference.
696  char *StrPtr = DebugInfoNames.Allocate<char>(Name.length());
697  memcpy(StrPtr, Name.data(), Name.length());
698  return llvm::StringRef(StrPtr, Name.length());
699}
700
701
702/// CollectVTableInfo - If the C++ class has vtable info then insert appropriate
703/// debug info entry in EltTys vector.
704void CGDebugInfo::
705CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile Unit,
706                  llvm::SmallVectorImpl<llvm::DIDescriptor> &EltTys) {
707  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
708
709  // If there is a primary base then it will hold vtable info.
710  if (RL.getPrimaryBase())
711    return;
712
713  // If this class is not dynamic then there is not any vtable info to collect.
714  if (!RD->isDynamicClass())
715    return;
716
717  unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
718  llvm::DIType VPTR
719    = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
720                                     getVTableName(RD), Unit,
721                                     0, Size, 0, 0, 0,
722                                     getOrCreateVTablePtrType(Unit));
723  EltTys.push_back(VPTR);
724}
725
726/// CreateType - get structure or union type.
727llvm::DIType CGDebugInfo::CreateType(const RecordType *Ty,
728                                     llvm::DIFile Unit) {
729  RecordDecl *RD = Ty->getDecl();
730
731  unsigned Tag;
732  if (RD->isStruct())
733    Tag = llvm::dwarf::DW_TAG_structure_type;
734  else if (RD->isUnion())
735    Tag = llvm::dwarf::DW_TAG_union_type;
736  else {
737    assert(RD->isClass() && "Unknown RecordType!");
738    Tag = llvm::dwarf::DW_TAG_class_type;
739  }
740
741  SourceManager &SM = CGM.getContext().getSourceManager();
742
743  // Get overall information about the record type for the debug info.
744  PresumedLoc PLoc = SM.getPresumedLoc(RD->getLocation());
745  llvm::DIFile DefUnit;
746  unsigned Line = 0;
747  if (!PLoc.isInvalid()) {
748    DefUnit = getOrCreateFile(RD->getLocation());
749    Line = PLoc.getLine();
750  }
751
752  // Records and classes and unions can all be recursive.  To handle them, we
753  // first generate a debug descriptor for the struct as a forward declaration.
754  // Then (if it is a definition) we go through and get debug info for all of
755  // its members.  Finally, we create a descriptor for the complete type (which
756  // may refer to the forward decl if the struct is recursive) and replace all
757  // uses of the forward declaration with the final definition.
758
759  // A RD->getName() is not unique. However, the debug info descriptors
760  // are uniqued so use type name to ensure uniquness.
761  llvm::SmallString<128> FwdDeclName;
762  llvm::raw_svector_ostream(FwdDeclName) << "fwd.type." << FwdDeclCount++;
763  llvm::DIDescriptor FDContext =
764    getContextDescriptor(dyn_cast<Decl>(RD->getDeclContext()), Unit);
765  llvm::DICompositeType FwdDecl =
766    DebugFactory.CreateCompositeType(Tag, FDContext, FwdDeclName,
767                                     DefUnit, Line, 0, 0, 0, 0,
768                                     llvm::DIType(), llvm::DIArray());
769
770  // If this is just a forward declaration, return it.
771  if (!RD->getDefinition())
772    return FwdDecl;
773
774  llvm::TrackingVH<llvm::MDNode> FwdDeclNode = FwdDecl.getNode();
775  // Otherwise, insert it into the TypeCache so that recursive uses will find
776  // it.
777  TypeCache[QualType(Ty, 0).getAsOpaquePtr()] = FwdDecl.getNode();
778  // Push the struct on region stack.
779  RegionStack.push_back(FwdDecl.getNode());
780  RegionMap[Ty->getDecl()] = llvm::WeakVH(FwdDecl.getNode());
781
782  // Convert all the elements.
783  llvm::SmallVector<llvm::DIDescriptor, 16> EltTys;
784
785  const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
786  if (CXXDecl) {
787    CollectCXXBases(CXXDecl, Unit, EltTys, FwdDecl);
788    CollectVTableInfo(CXXDecl, Unit, EltTys);
789  }
790  CollectRecordFields(RD, Unit, EltTys);
791  llvm::MDNode *ContainingType = NULL;
792  if (CXXDecl) {
793    CollectCXXMemberFunctions(CXXDecl, Unit, EltTys, FwdDecl);
794
795    // A class's primary base or the class itself contains the vtable.
796    const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
797    if (const CXXRecordDecl *PBase = RL.getPrimaryBase())
798      ContainingType =
799        getOrCreateType(QualType(PBase->getTypeForDecl(), 0), Unit).getNode();
800    else if (CXXDecl->isDynamicClass())
801      ContainingType = FwdDecl.getNode();
802  }
803
804  llvm::DIArray Elements =
805    DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
806
807  // Bit size, align and offset of the type.
808  uint64_t Size = CGM.getContext().getTypeSize(Ty);
809  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
810
811  RegionStack.pop_back();
812  llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator RI =
813    RegionMap.find(Ty->getDecl());
814  if (RI != RegionMap.end())
815    RegionMap.erase(RI);
816
817  llvm::DIDescriptor RDContext =
818    getContextDescriptor(dyn_cast<Decl>(RD->getDeclContext()), Unit);
819  llvm::DICompositeType RealDecl =
820    DebugFactory.CreateCompositeType(Tag, RDContext,
821                                     RD->getName(),
822                                     DefUnit, Line, Size, Align, 0, 0,
823                                     llvm::DIType(), Elements,
824                                     0, ContainingType);
825
826  // Now that we have a real decl for the struct, replace anything using the
827  // old decl with the new one.  This will recursively update the debug info.
828  llvm::DIDerivedType(FwdDeclNode).replaceAllUsesWith(RealDecl);
829  RegionMap[RD] = llvm::WeakVH(RealDecl.getNode());
830  return RealDecl;
831}
832
833/// CreateType - get objective-c interface type.
834llvm::DIType CGDebugInfo::CreateType(const ObjCInterfaceType *Ty,
835                                     llvm::DIFile Unit) {
836  ObjCInterfaceDecl *ID = Ty->getDecl();
837
838  unsigned Tag = llvm::dwarf::DW_TAG_structure_type;
839  SourceManager &SM = CGM.getContext().getSourceManager();
840
841  // Get overall information about the record type for the debug info.
842  llvm::DIFile DefUnit = getOrCreateFile(ID->getLocation());
843  PresumedLoc PLoc = SM.getPresumedLoc(ID->getLocation());
844  unsigned Line = PLoc.isInvalid() ? 0 : PLoc.getLine();
845
846
847  unsigned RuntimeLang = TheCU.getLanguage();
848
849  // To handle recursive interface, we
850  // first generate a debug descriptor for the struct as a forward declaration.
851  // Then (if it is a definition) we go through and get debug info for all of
852  // its members.  Finally, we create a descriptor for the complete type (which
853  // may refer to the forward decl if the struct is recursive) and replace all
854  // uses of the forward declaration with the final definition.
855  llvm::DICompositeType FwdDecl =
856    DebugFactory.CreateCompositeType(Tag, Unit, ID->getName(),
857                                     DefUnit, Line, 0, 0, 0, 0,
858                                     llvm::DIType(), llvm::DIArray(),
859                                     RuntimeLang);
860
861  // If this is just a forward declaration, return it.
862  if (ID->isForwardDecl())
863    return FwdDecl;
864
865  llvm::TrackingVH<llvm::MDNode> FwdDeclNode = FwdDecl.getNode();
866  // Otherwise, insert it into the TypeCache so that recursive uses will find
867  // it.
868  TypeCache[QualType(Ty, 0).getAsOpaquePtr()] = FwdDecl.getNode();
869  // Push the struct on region stack.
870  RegionStack.push_back(FwdDecl.getNode());
871  RegionMap[Ty->getDecl()] = llvm::WeakVH(FwdDecl.getNode());
872
873  // Convert all the elements.
874  llvm::SmallVector<llvm::DIDescriptor, 16> EltTys;
875
876  ObjCInterfaceDecl *SClass = ID->getSuperClass();
877  if (SClass) {
878    llvm::DIType SClassTy =
879      getOrCreateType(CGM.getContext().getObjCInterfaceType(SClass), Unit);
880    llvm::DIType InhTag =
881      DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_inheritance,
882                                     Unit, "", Unit, 0, 0, 0,
883                                     0 /* offset */, 0, SClassTy);
884    EltTys.push_back(InhTag);
885  }
886
887  const ASTRecordLayout &RL = CGM.getContext().getASTObjCInterfaceLayout(ID);
888
889  unsigned FieldNo = 0;
890  for (ObjCInterfaceDecl::ivar_iterator I = ID->ivar_begin(),
891         E = ID->ivar_end();  I != E; ++I, ++FieldNo) {
892    ObjCIvarDecl *Field = *I;
893    llvm::DIType FieldTy = getOrCreateType(Field->getType(), Unit);
894
895    llvm::StringRef FieldName = Field->getName();
896
897    // Ignore unnamed fields.
898    if (FieldName.empty())
899      continue;
900
901    // Get the location for the field.
902    SourceLocation FieldDefLoc = Field->getLocation();
903    llvm::DIFile FieldDefUnit = getOrCreateFile(FieldDefLoc);
904    PresumedLoc PLoc = SM.getPresumedLoc(FieldDefLoc);
905    unsigned FieldLine = PLoc.isInvalid() ? 0 : PLoc.getLine();
906
907
908    QualType FType = Field->getType();
909    uint64_t FieldSize = 0;
910    unsigned FieldAlign = 0;
911
912    if (!FType->isIncompleteArrayType()) {
913
914      // Bit size, align and offset of the type.
915      FieldSize = CGM.getContext().getTypeSize(FType);
916      Expr *BitWidth = Field->getBitWidth();
917      if (BitWidth)
918        FieldSize = BitWidth->EvaluateAsInt(CGM.getContext()).getZExtValue();
919
920      FieldAlign =  CGM.getContext().getTypeAlign(FType);
921    }
922
923    uint64_t FieldOffset = RL.getFieldOffset(FieldNo);
924
925    unsigned Flags = 0;
926    if (Field->getAccessControl() == ObjCIvarDecl::Protected)
927      Flags = llvm::DIType::FlagProtected;
928    else if (Field->getAccessControl() == ObjCIvarDecl::Private)
929      Flags = llvm::DIType::FlagPrivate;
930
931    // Create a DW_TAG_member node to remember the offset of this field in the
932    // struct.  FIXME: This is an absolutely insane way to capture this
933    // information.  When we gut debug info, this should be fixed.
934    FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
935                                             FieldName, FieldDefUnit,
936                                             FieldLine, FieldSize, FieldAlign,
937                                             FieldOffset, Flags, FieldTy);
938    EltTys.push_back(FieldTy);
939  }
940
941  llvm::DIArray Elements =
942    DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
943
944  RegionStack.pop_back();
945  llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator RI =
946    RegionMap.find(Ty->getDecl());
947  if (RI != RegionMap.end())
948    RegionMap.erase(RI);
949
950  // Bit size, align and offset of the type.
951  uint64_t Size = CGM.getContext().getTypeSize(Ty);
952  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
953
954  llvm::DICompositeType RealDecl =
955    DebugFactory.CreateCompositeType(Tag, Unit, ID->getName(), DefUnit,
956                                     Line, Size, Align, 0, 0, llvm::DIType(),
957                                     Elements, RuntimeLang);
958
959  // Now that we have a real decl for the struct, replace anything using the
960  // old decl with the new one.  This will recursively update the debug info.
961  llvm::DIDerivedType(FwdDeclNode).replaceAllUsesWith(RealDecl);
962  RegionMap[ID] = llvm::WeakVH(RealDecl.getNode());
963
964  return RealDecl;
965}
966
967llvm::DIType CGDebugInfo::CreateType(const EnumType *Ty,
968                                     llvm::DIFile Unit) {
969  EnumDecl *ED = Ty->getDecl();
970
971  llvm::SmallVector<llvm::DIDescriptor, 32> Enumerators;
972
973  // Create DIEnumerator elements for each enumerator.
974  for (EnumDecl::enumerator_iterator
975         Enum = ED->enumerator_begin(), EnumEnd = ED->enumerator_end();
976       Enum != EnumEnd; ++Enum) {
977    Enumerators.push_back(DebugFactory.CreateEnumerator(Enum->getName(),
978                                            Enum->getInitVal().getZExtValue()));
979  }
980
981  // Return a CompositeType for the enum itself.
982  llvm::DIArray EltArray =
983    DebugFactory.GetOrCreateArray(Enumerators.data(), Enumerators.size());
984
985  SourceLocation DefLoc = ED->getLocation();
986  llvm::DIFile DefUnit = getOrCreateFile(DefLoc);
987  SourceManager &SM = CGM.getContext().getSourceManager();
988  PresumedLoc PLoc = SM.getPresumedLoc(DefLoc);
989  unsigned Line = PLoc.isInvalid() ? 0 : PLoc.getLine();
990
991
992  // Size and align of the type.
993  uint64_t Size = 0;
994  unsigned Align = 0;
995  if (!Ty->isIncompleteType()) {
996    Size = CGM.getContext().getTypeSize(Ty);
997    Align = CGM.getContext().getTypeAlign(Ty);
998  }
999
1000  llvm::DIType DbgTy =
1001    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_enumeration_type,
1002                                     Unit, ED->getName(), DefUnit, Line,
1003                                     Size, Align, 0, 0,
1004                                     llvm::DIType(), EltArray);
1005  return DbgTy;
1006}
1007
1008llvm::DIType CGDebugInfo::CreateType(const TagType *Ty,
1009                                     llvm::DIFile Unit) {
1010  if (const RecordType *RT = dyn_cast<RecordType>(Ty))
1011    return CreateType(RT, Unit);
1012  else if (const EnumType *ET = dyn_cast<EnumType>(Ty))
1013    return CreateType(ET, Unit);
1014
1015  return llvm::DIType();
1016}
1017
1018llvm::DIType CGDebugInfo::CreateType(const VectorType *Ty,
1019				     llvm::DIFile Unit) {
1020  llvm::DIType ElementTy = getOrCreateType(Ty->getElementType(), Unit);
1021  uint64_t NumElems = Ty->getNumElements();
1022  if (NumElems > 0)
1023    --NumElems;
1024
1025  llvm::DIDescriptor Subscript = DebugFactory.GetOrCreateSubrange(0, NumElems);
1026  llvm::DIArray SubscriptArray = DebugFactory.GetOrCreateArray(&Subscript, 1);
1027
1028  uint64_t Size = CGM.getContext().getTypeSize(Ty);
1029  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
1030
1031  return
1032    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_vector_type,
1033                                     Unit, "", Unit,
1034                                     0, Size, Align, 0, 0,
1035				     ElementTy,  SubscriptArray);
1036}
1037
1038llvm::DIType CGDebugInfo::CreateType(const ArrayType *Ty,
1039                                     llvm::DIFile Unit) {
1040  uint64_t Size;
1041  uint64_t Align;
1042
1043
1044  // FIXME: make getTypeAlign() aware of VLAs and incomplete array types
1045  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(Ty)) {
1046    Size = 0;
1047    Align =
1048      CGM.getContext().getTypeAlign(CGM.getContext().getBaseElementType(VAT));
1049  } else if (Ty->isIncompleteArrayType()) {
1050    Size = 0;
1051    Align = CGM.getContext().getTypeAlign(Ty->getElementType());
1052  } else {
1053    // Size and align of the whole array, not the element type.
1054    Size = CGM.getContext().getTypeSize(Ty);
1055    Align = CGM.getContext().getTypeAlign(Ty);
1056  }
1057
1058  // Add the dimensions of the array.  FIXME: This loses CV qualifiers from
1059  // interior arrays, do we care?  Why aren't nested arrays represented the
1060  // obvious/recursive way?
1061  llvm::SmallVector<llvm::DIDescriptor, 8> Subscripts;
1062  QualType EltTy(Ty, 0);
1063  while ((Ty = dyn_cast<ArrayType>(EltTy))) {
1064    uint64_t Upper = 0;
1065    if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(Ty))
1066      if (CAT->getSize().getZExtValue())
1067        Upper = CAT->getSize().getZExtValue() - 1;
1068    // FIXME: Verify this is right for VLAs.
1069    Subscripts.push_back(DebugFactory.GetOrCreateSubrange(0, Upper));
1070    EltTy = Ty->getElementType();
1071  }
1072
1073  llvm::DIArray SubscriptArray =
1074    DebugFactory.GetOrCreateArray(Subscripts.data(), Subscripts.size());
1075
1076  llvm::DIType DbgTy =
1077    DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_array_type,
1078                                     Unit, "", Unit,
1079                                     0, Size, Align, 0, 0,
1080                                     getOrCreateType(EltTy, Unit),
1081                                     SubscriptArray);
1082  return DbgTy;
1083}
1084
1085llvm::DIType CGDebugInfo::CreateType(const LValueReferenceType *Ty,
1086                                     llvm::DIFile Unit) {
1087  return CreatePointerLikeType(llvm::dwarf::DW_TAG_reference_type,
1088                               Ty, Ty->getPointeeType(), Unit);
1089}
1090
1091llvm::DIType CGDebugInfo::CreateType(const MemberPointerType *Ty,
1092                                     llvm::DIFile U) {
1093  QualType PointerDiffTy = CGM.getContext().getPointerDiffType();
1094  llvm::DIType PointerDiffDITy = getOrCreateType(PointerDiffTy, U);
1095
1096  if (!Ty->getPointeeType()->isFunctionType()) {
1097    // We have a data member pointer type.
1098    return PointerDiffDITy;
1099  }
1100
1101  // We have a member function pointer type. Treat it as a struct with two
1102  // ptrdiff_t members.
1103  std::pair<uint64_t, unsigned> Info = CGM.getContext().getTypeInfo(Ty);
1104
1105  uint64_t FieldOffset = 0;
1106  llvm::DIDescriptor ElementTypes[2];
1107
1108  // FIXME: This should probably be a function type instead.
1109  ElementTypes[0] =
1110    DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, U,
1111                                   "ptr", U, 0,
1112                                   Info.first, Info.second, FieldOffset, 0,
1113                                   PointerDiffDITy);
1114  FieldOffset += Info.first;
1115
1116  ElementTypes[1] =
1117    DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, U,
1118                                   "ptr", U, 0,
1119                                   Info.first, Info.second, FieldOffset, 0,
1120                                   PointerDiffDITy);
1121
1122  llvm::DIArray Elements =
1123    DebugFactory.GetOrCreateArray(&ElementTypes[0],
1124                                  llvm::array_lengthof(ElementTypes));
1125
1126  return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_structure_type,
1127                                          U, llvm::StringRef("test"),
1128                                          U, 0, FieldOffset,
1129                                          0, 0, 0, llvm::DIType(), Elements);
1130}
1131
1132static QualType UnwrapTypeForDebugInfo(QualType T) {
1133  do {
1134    QualType LastT = T;
1135    switch (T->getTypeClass()) {
1136    default:
1137      return T;
1138    case Type::TemplateSpecialization:
1139      T = cast<TemplateSpecializationType>(T)->desugar();
1140      break;
1141    case Type::TypeOfExpr: {
1142      TypeOfExprType *Ty = cast<TypeOfExprType>(T);
1143      T = Ty->getUnderlyingExpr()->getType();
1144      break;
1145    }
1146    case Type::TypeOf:
1147      T = cast<TypeOfType>(T)->getUnderlyingType();
1148      break;
1149    case Type::Decltype:
1150      T = cast<DecltypeType>(T)->getUnderlyingType();
1151      break;
1152    case Type::QualifiedName:
1153      T = cast<QualifiedNameType>(T)->getNamedType();
1154      break;
1155    case Type::SubstTemplateTypeParm:
1156      T = cast<SubstTemplateTypeParmType>(T)->getReplacementType();
1157      break;
1158    case Type::Elaborated:
1159      T = cast<ElaboratedType>(T)->getUnderlyingType();
1160      break;
1161    }
1162
1163    assert(T != LastT && "Type unwrapping failed to unwrap!");
1164    if (T == LastT)
1165      return T;
1166  } while (true);
1167
1168  return T;
1169}
1170
1171/// getOrCreateType - Get the type from the cache or create a new
1172/// one if necessary.
1173llvm::DIType CGDebugInfo::getOrCreateType(QualType Ty,
1174                                          llvm::DIFile Unit) {
1175  if (Ty.isNull())
1176    return llvm::DIType();
1177
1178  // Unwrap the type as needed for debug information.
1179  Ty = UnwrapTypeForDebugInfo(Ty);
1180
1181  // Check for existing entry.
1182  llvm::DenseMap<void *, llvm::WeakVH>::iterator it =
1183    TypeCache.find(Ty.getAsOpaquePtr());
1184  if (it != TypeCache.end()) {
1185    // Verify that the debug info still exists.
1186    if (&*it->second)
1187      return llvm::DIType(cast<llvm::MDNode>(it->second));
1188  }
1189
1190  // Otherwise create the type.
1191  llvm::DIType Res = CreateTypeNode(Ty, Unit);
1192
1193  // And update the type cache.
1194  TypeCache[Ty.getAsOpaquePtr()] = Res.getNode();
1195  return Res;
1196}
1197
1198/// CreateTypeNode - Create a new debug type node.
1199llvm::DIType CGDebugInfo::CreateTypeNode(QualType Ty,
1200                                         llvm::DIFile Unit) {
1201  // Handle qualifiers, which recursively handles what they refer to.
1202  if (Ty.hasLocalQualifiers())
1203    return CreateQualifiedType(Ty, Unit);
1204
1205  const char *Diag = 0;
1206
1207  // Work out details of type.
1208  switch (Ty->getTypeClass()) {
1209#define TYPE(Class, Base)
1210#define ABSTRACT_TYPE(Class, Base)
1211#define NON_CANONICAL_TYPE(Class, Base)
1212#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1213#include "clang/AST/TypeNodes.def"
1214    assert(false && "Dependent types cannot show up in debug information");
1215
1216  // FIXME: Handle these.
1217  case Type::ExtVector:
1218    return llvm::DIType();
1219
1220  case Type::Vector:
1221    return CreateType(cast<VectorType>(Ty), Unit);
1222  case Type::ObjCObjectPointer:
1223    return CreateType(cast<ObjCObjectPointerType>(Ty), Unit);
1224  case Type::ObjCInterface:
1225    return CreateType(cast<ObjCInterfaceType>(Ty), Unit);
1226  case Type::Builtin: return CreateType(cast<BuiltinType>(Ty), Unit);
1227  case Type::Complex: return CreateType(cast<ComplexType>(Ty), Unit);
1228  case Type::Pointer: return CreateType(cast<PointerType>(Ty), Unit);
1229  case Type::BlockPointer:
1230    return CreateType(cast<BlockPointerType>(Ty), Unit);
1231  case Type::Typedef: return CreateType(cast<TypedefType>(Ty), Unit);
1232  case Type::Record:
1233  case Type::Enum:
1234    return CreateType(cast<TagType>(Ty), Unit);
1235  case Type::FunctionProto:
1236  case Type::FunctionNoProto:
1237    return CreateType(cast<FunctionType>(Ty), Unit);
1238  case Type::ConstantArray:
1239  case Type::VariableArray:
1240  case Type::IncompleteArray:
1241    return CreateType(cast<ArrayType>(Ty), Unit);
1242
1243  case Type::LValueReference:
1244    return CreateType(cast<LValueReferenceType>(Ty), Unit);
1245
1246  case Type::MemberPointer:
1247    return CreateType(cast<MemberPointerType>(Ty), Unit);
1248
1249  case Type::InjectedClassName:
1250  case Type::TemplateSpecialization:
1251  case Type::Elaborated:
1252  case Type::QualifiedName:
1253  case Type::SubstTemplateTypeParm:
1254  case Type::TypeOfExpr:
1255  case Type::TypeOf:
1256  case Type::Decltype:
1257    llvm_unreachable("type should have been unwrapped!");
1258    return llvm::DIType();
1259
1260  case Type::RValueReference:
1261    // FIXME: Implement!
1262    Diag = "rvalue references";
1263    break;
1264  }
1265
1266  assert(Diag && "Fall through without a diagnostic?");
1267  unsigned DiagID = CGM.getDiags().getCustomDiagID(Diagnostic::Error,
1268                               "debug information for %0 is not yet supported");
1269  CGM.getDiags().Report(FullSourceLoc(), DiagID)
1270    << Diag;
1271  return llvm::DIType();
1272}
1273
1274/// CreateMemberType - Create new member and increase Offset by FType's size.
1275llvm::DIType CGDebugInfo::CreateMemberType(llvm::DIFile Unit, QualType FType,
1276                                           llvm::StringRef Name,
1277                                           uint64_t *Offset) {
1278  llvm::DIType FieldTy = CGDebugInfo::getOrCreateType(FType, Unit);
1279  uint64_t FieldSize = CGM.getContext().getTypeSize(FType);
1280  unsigned FieldAlign = CGM.getContext().getTypeAlign(FType);
1281  llvm::DIType Ty = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member,
1282                                                   Unit, Name, Unit, 0,
1283                                                   FieldSize, FieldAlign,
1284                                                   *Offset, 0, FieldTy);
1285  *Offset += FieldSize;
1286  return Ty;
1287}
1288
1289/// EmitFunctionStart - Constructs the debug code for entering a function -
1290/// "llvm.dbg.func.start.".
1291void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, QualType FnType,
1292                                    llvm::Function *Fn,
1293                                    CGBuilderTy &Builder) {
1294
1295  llvm::StringRef Name;
1296  MangleBuffer LinkageName;
1297
1298  const Decl *D = GD.getDecl();
1299  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1300    // If there is a DISubprogram for  this function available then use it.
1301    llvm::DenseMap<const FunctionDecl *, llvm::WeakVH>::iterator
1302      FI = SPCache.find(FD);
1303    if (FI != SPCache.end()) {
1304      llvm::DIDescriptor SP(dyn_cast_or_null<llvm::MDNode>(FI->second));
1305      if (SP.isSubprogram() && llvm::DISubprogram(SP.getNode()).isDefinition()) {
1306        RegionStack.push_back(SP.getNode());
1307        RegionMap[D] = llvm::WeakVH(SP.getNode());
1308        return;
1309      }
1310    }
1311    Name = getFunctionName(FD);
1312    // Use mangled name as linkage name for c/c++ functions.
1313    CGM.getMangledName(LinkageName, GD);
1314  } else {
1315    // Use llvm function name as linkage name.
1316    Name = Fn->getName();
1317    LinkageName.setString(Name);
1318  }
1319  if (!Name.empty() && Name[0] == '\01')
1320    Name = Name.substr(1);
1321
1322  // It is expected that CurLoc is set before using EmitFunctionStart.
1323  // Usually, CurLoc points to the left bracket location of compound
1324  // statement representing function body.
1325  llvm::DIFile Unit = getOrCreateFile(CurLoc);
1326  SourceManager &SM = CGM.getContext().getSourceManager();
1327  unsigned LineNo = SM.getPresumedLoc(CurLoc).getLine();
1328
1329  llvm::DISubprogram SP =
1330    DebugFactory.CreateSubprogram(Unit, Name, Name, LinkageName, Unit, LineNo,
1331                                  getOrCreateType(FnType, Unit),
1332                                  Fn->hasInternalLinkage(), true/*definition*/);
1333
1334  // Push function on region stack.
1335  RegionStack.push_back(SP.getNode());
1336  RegionMap[D] = llvm::WeakVH(SP.getNode());
1337}
1338
1339
1340void CGDebugInfo::EmitStopPoint(llvm::Function *Fn, CGBuilderTy &Builder) {
1341  if (CurLoc.isInvalid() || CurLoc.isMacroID()) return;
1342
1343  // Don't bother if things are the same as last time.
1344  SourceManager &SM = CGM.getContext().getSourceManager();
1345  if (CurLoc == PrevLoc
1346       || (SM.getInstantiationLineNumber(CurLoc) ==
1347           SM.getInstantiationLineNumber(PrevLoc)
1348           && SM.isFromSameFile(CurLoc, PrevLoc)))
1349    // New Builder may not be in sync with CGDebugInfo.
1350    if (!Builder.getCurrentDebugLocation().isUnknown())
1351      return;
1352
1353  // Update last state.
1354  PrevLoc = CurLoc;
1355
1356  // Get the appropriate compile unit.
1357  llvm::DIFile Unit = getOrCreateFile(CurLoc);
1358  PresumedLoc PLoc = SM.getPresumedLoc(CurLoc);
1359
1360  llvm::MDNode *Scope = RegionStack.back();
1361  Builder.SetCurrentDebugLocation(llvm::DebugLoc::get(PLoc.getLine(),
1362                                                      PLoc.getColumn(),
1363                                                      Scope));
1364}
1365
1366/// EmitRegionStart- Constructs the debug code for entering a declarative
1367/// region - "llvm.dbg.region.start.".
1368void CGDebugInfo::EmitRegionStart(llvm::Function *Fn, CGBuilderTy &Builder) {
1369  SourceManager &SM = CGM.getContext().getSourceManager();
1370  PresumedLoc PLoc = SM.getPresumedLoc(CurLoc);
1371  llvm::DIDescriptor D =
1372    DebugFactory.CreateLexicalBlock(RegionStack.empty() ?
1373                                    llvm::DIDescriptor() :
1374                                    llvm::DIDescriptor(RegionStack.back()),
1375                                    PLoc.getLine(), PLoc.getColumn());
1376  RegionStack.push_back(D.getNode());
1377}
1378
1379/// EmitRegionEnd - Constructs the debug code for exiting a declarative
1380/// region - "llvm.dbg.region.end."
1381void CGDebugInfo::EmitRegionEnd(llvm::Function *Fn, CGBuilderTy &Builder) {
1382  assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
1383
1384  // Provide an region stop point.
1385  EmitStopPoint(Fn, Builder);
1386
1387  RegionStack.pop_back();
1388}
1389
1390// EmitTypeForVarWithBlocksAttr - Build up structure info for the byref.
1391// See BuildByRefType.
1392llvm::DIType CGDebugInfo::EmitTypeForVarWithBlocksAttr(const ValueDecl *VD,
1393                                                       uint64_t *XOffset) {
1394
1395  llvm::SmallVector<llvm::DIDescriptor, 5> EltTys;
1396
1397  QualType FType;
1398  uint64_t FieldSize, FieldOffset;
1399  unsigned FieldAlign;
1400
1401  llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
1402  QualType Type = VD->getType();
1403
1404  FieldOffset = 0;
1405  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
1406  EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
1407  EltTys.push_back(CreateMemberType(Unit, FType, "__forwarding", &FieldOffset));
1408  FType = CGM.getContext().IntTy;
1409  EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
1410  EltTys.push_back(CreateMemberType(Unit, FType, "__size", &FieldOffset));
1411
1412  bool HasCopyAndDispose = CGM.BlockRequiresCopying(Type);
1413  if (HasCopyAndDispose) {
1414    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
1415    EltTys.push_back(CreateMemberType(Unit, FType, "__copy_helper",
1416                                      &FieldOffset));
1417    EltTys.push_back(CreateMemberType(Unit, FType, "__destroy_helper",
1418                                      &FieldOffset));
1419  }
1420
1421  CharUnits Align = CGM.getContext().getDeclAlign(VD);
1422  if (Align > CharUnits::fromQuantity(
1423        CGM.getContext().Target.getPointerAlign(0) / 8)) {
1424    unsigned AlignedOffsetInBytes
1425      = llvm::RoundUpToAlignment(FieldOffset/8, Align.getQuantity());
1426    unsigned NumPaddingBytes
1427      = AlignedOffsetInBytes - FieldOffset/8;
1428
1429    if (NumPaddingBytes > 0) {
1430      llvm::APInt pad(32, NumPaddingBytes);
1431      FType = CGM.getContext().getConstantArrayType(CGM.getContext().CharTy,
1432                                                    pad, ArrayType::Normal, 0);
1433      EltTys.push_back(CreateMemberType(Unit, FType, "", &FieldOffset));
1434    }
1435  }
1436
1437  FType = Type;
1438  llvm::DIType FieldTy = CGDebugInfo::getOrCreateType(FType, Unit);
1439  FieldSize = CGM.getContext().getTypeSize(FType);
1440  FieldAlign = Align.getQuantity()*8;
1441
1442  *XOffset = FieldOffset;
1443  FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
1444                                           VD->getName(), Unit,
1445                                           0, FieldSize, FieldAlign,
1446                                           FieldOffset, 0, FieldTy);
1447  EltTys.push_back(FieldTy);
1448  FieldOffset += FieldSize;
1449
1450  llvm::DIArray Elements =
1451    DebugFactory.GetOrCreateArray(EltTys.data(), EltTys.size());
1452
1453  unsigned Flags = llvm::DIType::FlagBlockByrefStruct;
1454
1455  return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_structure_type,
1456                                          Unit, "", Unit,
1457                                          0, FieldOffset, 0, 0, Flags,
1458                                          llvm::DIType(), Elements);
1459
1460}
1461/// EmitDeclare - Emit local variable declaration debug info.
1462void CGDebugInfo::EmitDeclare(const VarDecl *VD, unsigned Tag,
1463                              llvm::Value *Storage, CGBuilderTy &Builder) {
1464  assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
1465
1466  // Do not emit variable debug information while generating optimized code.
1467  // The llvm optimizer and code generator are not yet ready to support
1468  // optimized code debugging.
1469  const CodeGenOptions &CGO = CGM.getCodeGenOpts();
1470  if (CGO.OptimizationLevel)
1471    return;
1472
1473  llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
1474  llvm::DIType Ty;
1475  uint64_t XOffset = 0;
1476  if (VD->hasAttr<BlocksAttr>())
1477    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset);
1478  else
1479    Ty = getOrCreateType(VD->getType(), Unit);
1480
1481  // Get location information.
1482  SourceManager &SM = CGM.getContext().getSourceManager();
1483  PresumedLoc PLoc = SM.getPresumedLoc(VD->getLocation());
1484  unsigned Line = 0;
1485  unsigned Column = 0;
1486  if (PLoc.isInvalid())
1487    PLoc = SM.getPresumedLoc(CurLoc);
1488  if (PLoc.isValid()) {
1489    Line = PLoc.getLine();
1490    Column = PLoc.getColumn();
1491    Unit = getOrCreateFile(CurLoc);
1492  } else {
1493    Unit = llvm::DIFile();
1494  }
1495
1496  // Create the descriptor for the variable.
1497  llvm::DIVariable D =
1498    DebugFactory.CreateVariable(Tag, llvm::DIDescriptor(RegionStack.back()),
1499                                VD->getName(),
1500                                Unit, Line, Ty);
1501  // Insert an llvm.dbg.declare into the current block.
1502  llvm::Instruction *Call =
1503    DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertBlock());
1504
1505  llvm::MDNode *Scope = RegionStack.back();
1506  Call->setDebugLoc(llvm::DebugLoc::get(Line, Column, Scope));
1507}
1508
1509/// EmitDeclare - Emit local variable declaration debug info.
1510void CGDebugInfo::EmitDeclare(const BlockDeclRefExpr *BDRE, unsigned Tag,
1511                              llvm::Value *Storage, CGBuilderTy &Builder,
1512                              CodeGenFunction *CGF) {
1513  const ValueDecl *VD = BDRE->getDecl();
1514  assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
1515
1516  // Do not emit variable debug information while generating optimized code.
1517  // The llvm optimizer and code generator are not yet ready to support
1518  // optimized code debugging.
1519  const CodeGenOptions &CGO = CGM.getCodeGenOpts();
1520  if (CGO.OptimizationLevel || Builder.GetInsertBlock() == 0)
1521    return;
1522
1523  uint64_t XOffset = 0;
1524  llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
1525  llvm::DIType Ty;
1526  if (VD->hasAttr<BlocksAttr>())
1527    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset);
1528  else
1529    Ty = getOrCreateType(VD->getType(), Unit);
1530
1531  // Get location information.
1532  SourceManager &SM = CGM.getContext().getSourceManager();
1533  PresumedLoc PLoc = SM.getPresumedLoc(VD->getLocation());
1534  unsigned Line = 0;
1535  if (!PLoc.isInvalid())
1536    Line = PLoc.getLine();
1537  else
1538    Unit = llvm::DIFile();
1539
1540  CharUnits offset = CGF->BlockDecls[VD];
1541  llvm::SmallVector<llvm::Value *, 9> addr;
1542  const llvm::Type *Int64Ty = llvm::Type::getInt64Ty(CGM.getLLVMContext());
1543  addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpDeref));
1544  addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpPlus));
1545  addr.push_back(llvm::ConstantInt::get(Int64Ty, offset.getQuantity()));
1546  if (BDRE->isByRef()) {
1547    addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpDeref));
1548    addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpPlus));
1549    // offset of __forwarding field
1550    offset = CharUnits::fromQuantity(CGF->LLVMPointerWidth/8);
1551    addr.push_back(llvm::ConstantInt::get(Int64Ty, offset.getQuantity()));
1552    addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpDeref));
1553    addr.push_back(llvm::ConstantInt::get(Int64Ty, llvm::DIFactory::OpPlus));
1554    // offset of x field
1555    offset = CharUnits::fromQuantity(XOffset/8);
1556    addr.push_back(llvm::ConstantInt::get(Int64Ty, offset.getQuantity()));
1557  }
1558
1559  // Create the descriptor for the variable.
1560  llvm::DIVariable D =
1561    DebugFactory.CreateComplexVariable(Tag,
1562                                       llvm::DIDescriptor(RegionStack.back()),
1563                                       VD->getName(), Unit, Line, Ty,
1564                                       addr);
1565  // Insert an llvm.dbg.declare into the current block.
1566  llvm::Instruction *Call =
1567    DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertBlock());
1568
1569  llvm::MDNode *Scope = RegionStack.back();
1570  Call->setDebugLoc(llvm::DebugLoc::get(Line, PLoc.getColumn(), Scope));
1571}
1572
1573void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD,
1574                                            llvm::Value *Storage,
1575                                            CGBuilderTy &Builder) {
1576  EmitDeclare(VD, llvm::dwarf::DW_TAG_auto_variable, Storage, Builder);
1577}
1578
1579void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
1580  const BlockDeclRefExpr *BDRE, llvm::Value *Storage, CGBuilderTy &Builder,
1581  CodeGenFunction *CGF) {
1582  EmitDeclare(BDRE, llvm::dwarf::DW_TAG_auto_variable, Storage, Builder, CGF);
1583}
1584
1585/// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument
1586/// variable declaration.
1587void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
1588                                           CGBuilderTy &Builder) {
1589  EmitDeclare(VD, llvm::dwarf::DW_TAG_arg_variable, AI, Builder);
1590}
1591
1592
1593
1594/// EmitGlobalVariable - Emit information about a global variable.
1595void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
1596                                     const VarDecl *D) {
1597
1598  // Create global variable debug descriptor.
1599  llvm::DIFile Unit = getOrCreateFile(D->getLocation());
1600  SourceManager &SM = CGM.getContext().getSourceManager();
1601  PresumedLoc PLoc = SM.getPresumedLoc(D->getLocation());
1602  unsigned LineNo = PLoc.isInvalid() ? 0 : PLoc.getLine();
1603
1604  QualType T = D->getType();
1605  if (T->isIncompleteArrayType()) {
1606
1607    // CodeGen turns int[] into int[1] so we'll do the same here.
1608    llvm::APSInt ConstVal(32);
1609
1610    ConstVal = 1;
1611    QualType ET = CGM.getContext().getAsArrayType(T)->getElementType();
1612
1613    T = CGM.getContext().getConstantArrayType(ET, ConstVal,
1614                                           ArrayType::Normal, 0);
1615  }
1616  llvm::StringRef DeclName = Var->getName();
1617  llvm::DIDescriptor DContext =
1618    getContextDescriptor(dyn_cast<Decl>(D->getDeclContext()), Unit);
1619  DebugFactory.CreateGlobalVariable(DContext, DeclName,
1620                                    DeclName, llvm::StringRef(), Unit, LineNo,
1621                                    getOrCreateType(T, Unit),
1622                                    Var->hasInternalLinkage(),
1623                                    true/*definition*/, Var);
1624}
1625
1626/// EmitGlobalVariable - Emit information about an objective-c interface.
1627void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
1628                                     ObjCInterfaceDecl *ID) {
1629  // Create global variable debug descriptor.
1630  llvm::DIFile Unit = getOrCreateFile(ID->getLocation());
1631  SourceManager &SM = CGM.getContext().getSourceManager();
1632  PresumedLoc PLoc = SM.getPresumedLoc(ID->getLocation());
1633  unsigned LineNo = PLoc.isInvalid() ? 0 : PLoc.getLine();
1634
1635  llvm::StringRef Name = ID->getName();
1636
1637  QualType T = CGM.getContext().getObjCInterfaceType(ID);
1638  if (T->isIncompleteArrayType()) {
1639
1640    // CodeGen turns int[] into int[1] so we'll do the same here.
1641    llvm::APSInt ConstVal(32);
1642
1643    ConstVal = 1;
1644    QualType ET = CGM.getContext().getAsArrayType(T)->getElementType();
1645
1646    T = CGM.getContext().getConstantArrayType(ET, ConstVal,
1647                                           ArrayType::Normal, 0);
1648  }
1649
1650  DebugFactory.CreateGlobalVariable(Unit, Name, Name, Name, Unit, LineNo,
1651                                    getOrCreateType(T, Unit),
1652                                    Var->hasInternalLinkage(),
1653                                    true/*definition*/, Var);
1654}
1655
1656/// getOrCreateNamesSpace - Return namespace descriptor for the given
1657/// namespace decl.
1658llvm::DINameSpace
1659CGDebugInfo::getOrCreateNameSpace(const NamespaceDecl *NSDecl,
1660                                  llvm::DIDescriptor Unit) {
1661  llvm::DenseMap<const NamespaceDecl *, llvm::WeakVH>::iterator I =
1662    NameSpaceCache.find(NSDecl);
1663  if (I != NameSpaceCache.end())
1664    return llvm::DINameSpace(cast<llvm::MDNode>(I->second));
1665
1666  SourceManager &SM = CGM.getContext().getSourceManager();
1667  PresumedLoc PLoc = SM.getPresumedLoc(NSDecl->getLocation());
1668  unsigned LineNo = PLoc.isInvalid() ? 0 : PLoc.getLine();
1669
1670  llvm::DIDescriptor Context =
1671    getContextDescriptor(dyn_cast<Decl>(NSDecl->getDeclContext()), Unit);
1672  llvm::DINameSpace NS =
1673    DebugFactory.CreateNameSpace(Context, NSDecl->getName(),
1674	llvm::DIFile(Unit.getNode()), LineNo);
1675  NameSpaceCache[NSDecl] = llvm::WeakVH(NS.getNode());
1676  return NS;
1677}
1678