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 "CGBlocks.h"
16#include "CGCXXABI.h"
17#include "CGObjCRuntime.h"
18#include "CodeGenFunction.h"
19#include "CodeGenModule.h"
20#include "clang/AST/ASTContext.h"
21#include "clang/AST/DeclFriend.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/DeclTemplate.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/RecordLayout.h"
26#include "clang/Basic/FileManager.h"
27#include "clang/Basic/SourceManager.h"
28#include "clang/Basic/Version.h"
29#include "clang/Frontend/CodeGenOptions.h"
30#include "clang/Lex/HeaderSearchOptions.h"
31#include "clang/Lex/ModuleMap.h"
32#include "clang/Lex/PreprocessorOptions.h"
33#include "llvm/ADT/SmallVector.h"
34#include "llvm/ADT/StringExtras.h"
35#include "llvm/IR/Constants.h"
36#include "llvm/IR/DataLayout.h"
37#include "llvm/IR/DerivedTypes.h"
38#include "llvm/IR/Instructions.h"
39#include "llvm/IR/Intrinsics.h"
40#include "llvm/IR/Module.h"
41#include "llvm/Support/FileSystem.h"
42#include "llvm/Support/Path.h"
43using namespace clang;
44using namespace clang::CodeGen;
45
46CGDebugInfo::CGDebugInfo(CodeGenModule &CGM)
47    : CGM(CGM), DebugKind(CGM.getCodeGenOpts().getDebugInfo()),
48      DebugTypeExtRefs(CGM.getCodeGenOpts().DebugTypeExtRefs),
49      DBuilder(CGM.getModule()) {
50  for (const auto &KV : CGM.getCodeGenOpts().DebugPrefixMap)
51    DebugPrefixMap[KV.first] = KV.second;
52  CreateCompileUnit();
53}
54
55CGDebugInfo::~CGDebugInfo() {
56  assert(LexicalBlockStack.empty() &&
57         "Region stack mismatch, stack not empty!");
58}
59
60ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
61                                       SourceLocation TemporaryLocation)
62    : CGF(&CGF) {
63  init(TemporaryLocation);
64}
65
66ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
67                                       bool DefaultToEmpty,
68                                       SourceLocation TemporaryLocation)
69    : CGF(&CGF) {
70  init(TemporaryLocation, DefaultToEmpty);
71}
72
73void ApplyDebugLocation::init(SourceLocation TemporaryLocation,
74                              bool DefaultToEmpty) {
75  auto *DI = CGF->getDebugInfo();
76  if (!DI) {
77    CGF = nullptr;
78    return;
79  }
80
81  OriginalLocation = CGF->Builder.getCurrentDebugLocation();
82  if (TemporaryLocation.isValid()) {
83    DI->EmitLocation(CGF->Builder, TemporaryLocation);
84    return;
85  }
86
87  if (DefaultToEmpty) {
88    CGF->Builder.SetCurrentDebugLocation(llvm::DebugLoc());
89    return;
90  }
91
92  // Construct a location that has a valid scope, but no line info.
93  assert(!DI->LexicalBlockStack.empty());
94  CGF->Builder.SetCurrentDebugLocation(
95      llvm::DebugLoc::get(0, 0, DI->LexicalBlockStack.back()));
96}
97
98ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E)
99    : CGF(&CGF) {
100  init(E->getExprLoc());
101}
102
103ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc)
104    : CGF(&CGF) {
105  if (!CGF.getDebugInfo()) {
106    this->CGF = nullptr;
107    return;
108  }
109  OriginalLocation = CGF.Builder.getCurrentDebugLocation();
110  if (Loc)
111    CGF.Builder.SetCurrentDebugLocation(std::move(Loc));
112}
113
114ApplyDebugLocation::~ApplyDebugLocation() {
115  // Query CGF so the location isn't overwritten when location updates are
116  // temporarily disabled (for C++ default function arguments)
117  if (CGF)
118    CGF->Builder.SetCurrentDebugLocation(std::move(OriginalLocation));
119}
120
121void CGDebugInfo::setLocation(SourceLocation Loc) {
122  // If the new location isn't valid return.
123  if (Loc.isInvalid())
124    return;
125
126  CurLoc = CGM.getContext().getSourceManager().getExpansionLoc(Loc);
127
128  // If we've changed files in the middle of a lexical scope go ahead
129  // and create a new lexical scope with file node if it's different
130  // from the one in the scope.
131  if (LexicalBlockStack.empty())
132    return;
133
134  SourceManager &SM = CGM.getContext().getSourceManager();
135  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
136  PresumedLoc PCLoc = SM.getPresumedLoc(CurLoc);
137
138  if (PCLoc.isInvalid() || Scope->getFilename() == PCLoc.getFilename())
139    return;
140
141  if (auto *LBF = dyn_cast<llvm::DILexicalBlockFile>(Scope)) {
142    LexicalBlockStack.pop_back();
143    LexicalBlockStack.emplace_back(DBuilder.createLexicalBlockFile(
144        LBF->getScope(), getOrCreateFile(CurLoc)));
145  } else if (isa<llvm::DILexicalBlock>(Scope) ||
146             isa<llvm::DISubprogram>(Scope)) {
147    LexicalBlockStack.pop_back();
148    LexicalBlockStack.emplace_back(
149        DBuilder.createLexicalBlockFile(Scope, getOrCreateFile(CurLoc)));
150  }
151}
152
153llvm::DIScope *CGDebugInfo::getDeclContextDescriptor(const Decl *D) {
154  llvm::DIScope *Mod = getParentModuleOrNull(D);
155  return getContextDescriptor(cast<Decl>(D->getDeclContext()),
156                              Mod ? Mod : TheCU);
157}
158
159llvm::DIScope *CGDebugInfo::getContextDescriptor(const Decl *Context,
160                                                 llvm::DIScope *Default) {
161  if (!Context)
162    return Default;
163
164  auto I = RegionMap.find(Context);
165  if (I != RegionMap.end()) {
166    llvm::Metadata *V = I->second;
167    return dyn_cast_or_null<llvm::DIScope>(V);
168  }
169
170  // Check namespace.
171  if (const NamespaceDecl *NSDecl = dyn_cast<NamespaceDecl>(Context))
172    return getOrCreateNameSpace(NSDecl);
173
174  if (const RecordDecl *RDecl = dyn_cast<RecordDecl>(Context))
175    if (!RDecl->isDependentType())
176      return getOrCreateType(CGM.getContext().getTypeDeclType(RDecl),
177                             getOrCreateMainFile());
178  return Default;
179}
180
181StringRef CGDebugInfo::getFunctionName(const FunctionDecl *FD) {
182  assert(FD && "Invalid FunctionDecl!");
183  IdentifierInfo *FII = FD->getIdentifier();
184  FunctionTemplateSpecializationInfo *Info =
185      FD->getTemplateSpecializationInfo();
186
187  if (!Info && FII && !CGM.getCodeGenOpts().EmitCodeView)
188    return FII->getName();
189
190  // Otherwise construct human readable name for debug info.
191  SmallString<128> NS;
192  llvm::raw_svector_ostream OS(NS);
193  PrintingPolicy Policy(CGM.getLangOpts());
194
195  if (CGM.getCodeGenOpts().EmitCodeView) {
196    // Print a fully qualified name like MSVC would.
197    Policy.MSVCFormatting = true;
198    FD->printQualifiedName(OS, Policy);
199  } else {
200    // Print the unqualified name with some template arguments. This is what
201    // DWARF-based debuggers expect.
202    FD->printName(OS);
203    // Add any template specialization args.
204    if (Info) {
205      const TemplateArgumentList *TArgs = Info->TemplateArguments;
206      const TemplateArgument *Args = TArgs->data();
207      unsigned NumArgs = TArgs->size();
208      TemplateSpecializationType::PrintTemplateArgumentList(OS, Args, NumArgs,
209                                                            Policy);
210    }
211  }
212
213  // Copy this name on the side and use its reference.
214  return internString(OS.str());
215}
216
217StringRef CGDebugInfo::getObjCMethodName(const ObjCMethodDecl *OMD) {
218  SmallString<256> MethodName;
219  llvm::raw_svector_ostream OS(MethodName);
220  OS << (OMD->isInstanceMethod() ? '-' : '+') << '[';
221  const DeclContext *DC = OMD->getDeclContext();
222  if (const ObjCImplementationDecl *OID =
223          dyn_cast<const ObjCImplementationDecl>(DC)) {
224    OS << OID->getName();
225  } else if (const ObjCInterfaceDecl *OID =
226                 dyn_cast<const ObjCInterfaceDecl>(DC)) {
227    OS << OID->getName();
228  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(DC)) {
229    if (OC->IsClassExtension()) {
230      OS << OC->getClassInterface()->getName();
231    } else {
232      OS << ((const NamedDecl *)OC)->getIdentifier()->getNameStart() << '('
233         << OC->getIdentifier()->getNameStart() << ')';
234    }
235  } else if (const ObjCCategoryImplDecl *OCD =
236                 dyn_cast<const ObjCCategoryImplDecl>(DC)) {
237    OS << ((const NamedDecl *)OCD)->getIdentifier()->getNameStart() << '('
238       << OCD->getIdentifier()->getNameStart() << ')';
239  } else if (isa<ObjCProtocolDecl>(DC)) {
240    // We can extract the type of the class from the self pointer.
241    if (ImplicitParamDecl *SelfDecl = OMD->getSelfDecl()) {
242      QualType ClassTy =
243          cast<ObjCObjectPointerType>(SelfDecl->getType())->getPointeeType();
244      ClassTy.print(OS, PrintingPolicy(LangOptions()));
245    }
246  }
247  OS << ' ' << OMD->getSelector().getAsString() << ']';
248
249  return internString(OS.str());
250}
251
252StringRef CGDebugInfo::getSelectorName(Selector S) {
253  return internString(S.getAsString());
254}
255
256StringRef CGDebugInfo::getClassName(const RecordDecl *RD) {
257  // quick optimization to avoid having to intern strings that are already
258  // stored reliably elsewhere
259  if (!isa<ClassTemplateSpecializationDecl>(RD))
260    return RD->getName();
261
262  SmallString<128> Name;
263  {
264    llvm::raw_svector_ostream OS(Name);
265    RD->getNameForDiagnostic(OS, CGM.getContext().getPrintingPolicy(),
266                             /*Qualified*/ false);
267  }
268
269  // Copy this name on the side and use its reference.
270  return internString(Name);
271}
272
273llvm::DIFile *CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
274  if (!Loc.isValid())
275    // If Location is not valid then use main input file.
276    return DBuilder.createFile(remapDIPath(TheCU->getFilename()),
277                               remapDIPath(TheCU->getDirectory()));
278
279  SourceManager &SM = CGM.getContext().getSourceManager();
280  PresumedLoc PLoc = SM.getPresumedLoc(Loc);
281
282  if (PLoc.isInvalid() || StringRef(PLoc.getFilename()).empty())
283    // If the location is not valid then use main input file.
284    return DBuilder.createFile(remapDIPath(TheCU->getFilename()),
285                               remapDIPath(TheCU->getDirectory()));
286
287  // Cache the results.
288  const char *fname = PLoc.getFilename();
289  auto it = DIFileCache.find(fname);
290
291  if (it != DIFileCache.end()) {
292    // Verify that the information still exists.
293    if (llvm::Metadata *V = it->second)
294      return cast<llvm::DIFile>(V);
295  }
296
297  llvm::DIFile *F = DBuilder.createFile(remapDIPath(PLoc.getFilename()),
298                                        remapDIPath(getCurrentDirname()));
299
300  DIFileCache[fname].reset(F);
301  return F;
302}
303
304llvm::DIFile *CGDebugInfo::getOrCreateMainFile() {
305  return DBuilder.createFile(remapDIPath(TheCU->getFilename()),
306                             remapDIPath(TheCU->getDirectory()));
307}
308
309std::string CGDebugInfo::remapDIPath(StringRef Path) const {
310  for (const auto &Entry : DebugPrefixMap)
311    if (Path.startswith(Entry.first))
312      return (Twine(Entry.second) + Path.substr(Entry.first.size())).str();
313  return Path.str();
314}
315
316unsigned CGDebugInfo::getLineNumber(SourceLocation Loc) {
317  if (Loc.isInvalid() && CurLoc.isInvalid())
318    return 0;
319  SourceManager &SM = CGM.getContext().getSourceManager();
320  PresumedLoc PLoc = SM.getPresumedLoc(Loc.isValid() ? Loc : CurLoc);
321  return PLoc.isValid() ? PLoc.getLine() : 0;
322}
323
324unsigned CGDebugInfo::getColumnNumber(SourceLocation Loc, bool Force) {
325  // We may not want column information at all.
326  if (!Force && !CGM.getCodeGenOpts().DebugColumnInfo)
327    return 0;
328
329  // If the location is invalid then use the current column.
330  if (Loc.isInvalid() && CurLoc.isInvalid())
331    return 0;
332  SourceManager &SM = CGM.getContext().getSourceManager();
333  PresumedLoc PLoc = SM.getPresumedLoc(Loc.isValid() ? Loc : CurLoc);
334  return PLoc.isValid() ? PLoc.getColumn() : 0;
335}
336
337StringRef CGDebugInfo::getCurrentDirname() {
338  if (!CGM.getCodeGenOpts().DebugCompilationDir.empty())
339    return CGM.getCodeGenOpts().DebugCompilationDir;
340
341  if (!CWDName.empty())
342    return CWDName;
343  SmallString<256> CWD;
344  llvm::sys::fs::current_path(CWD);
345  return CWDName = internString(CWD);
346}
347
348void CGDebugInfo::CreateCompileUnit() {
349
350  // Should we be asking the SourceManager for the main file name, instead of
351  // accepting it as an argument? This just causes the main file name to
352  // mismatch with source locations and create extra lexical scopes or
353  // mismatched debug info (a CU with a DW_AT_file of "-", because that's what
354  // the driver passed, but functions/other things have DW_AT_file of "<stdin>"
355  // because that's what the SourceManager says)
356
357  // Get absolute path name.
358  SourceManager &SM = CGM.getContext().getSourceManager();
359  std::string MainFileName = CGM.getCodeGenOpts().MainFileName;
360  if (MainFileName.empty())
361    MainFileName = "<stdin>";
362
363  // The main file name provided via the "-main-file-name" option contains just
364  // the file name itself with no path information. This file name may have had
365  // a relative path, so we look into the actual file entry for the main
366  // file to determine the real absolute path for the file.
367  std::string MainFileDir;
368  if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
369    MainFileDir = remapDIPath(MainFile->getDir()->getName());
370    if (MainFileDir != ".") {
371      llvm::SmallString<1024> MainFileDirSS(MainFileDir);
372      llvm::sys::path::append(MainFileDirSS, MainFileName);
373      MainFileName = MainFileDirSS.str();
374    }
375  }
376
377  llvm::dwarf::SourceLanguage LangTag;
378  const LangOptions &LO = CGM.getLangOpts();
379  if (LO.CPlusPlus) {
380    if (LO.ObjC1)
381      LangTag = llvm::dwarf::DW_LANG_ObjC_plus_plus;
382    else
383      LangTag = llvm::dwarf::DW_LANG_C_plus_plus;
384  } else if (LO.ObjC1) {
385    LangTag = llvm::dwarf::DW_LANG_ObjC;
386  } else if (LO.C99) {
387    LangTag = llvm::dwarf::DW_LANG_C99;
388  } else {
389    LangTag = llvm::dwarf::DW_LANG_C89;
390  }
391
392  std::string Producer = getClangFullVersion();
393
394  // Figure out which version of the ObjC runtime we have.
395  unsigned RuntimeVers = 0;
396  if (LO.ObjC1)
397    RuntimeVers = LO.ObjCRuntime.isNonFragile() ? 2 : 1;
398
399  // Create new compile unit.
400  // FIXME - Eliminate TheCU.
401  TheCU = DBuilder.createCompileUnit(
402      LangTag, remapDIPath(MainFileName), remapDIPath(getCurrentDirname()),
403      Producer, LO.Optimize, CGM.getCodeGenOpts().DwarfDebugFlags, RuntimeVers,
404      CGM.getCodeGenOpts().SplitDwarfFile,
405      DebugKind <= CodeGenOptions::DebugLineTablesOnly
406          ? llvm::DIBuilder::LineTablesOnly
407          : llvm::DIBuilder::FullDebug,
408      0 /* DWOid */, DebugKind != CodeGenOptions::LocTrackingOnly);
409}
410
411llvm::DIType *CGDebugInfo::CreateType(const BuiltinType *BT) {
412  llvm::dwarf::TypeKind Encoding;
413  StringRef BTName;
414  switch (BT->getKind()) {
415#define BUILTIN_TYPE(Id, SingletonId)
416#define PLACEHOLDER_TYPE(Id, SingletonId) case BuiltinType::Id:
417#include "clang/AST/BuiltinTypes.def"
418  case BuiltinType::Dependent:
419    llvm_unreachable("Unexpected builtin type");
420  case BuiltinType::NullPtr:
421    return DBuilder.createNullPtrType();
422  case BuiltinType::Void:
423    return nullptr;
424  case BuiltinType::ObjCClass:
425    if (!ClassTy)
426      ClassTy = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
427                                           "objc_class", TheCU,
428                                           getOrCreateMainFile(), 0);
429    return ClassTy;
430  case BuiltinType::ObjCId: {
431    // typedef struct objc_class *Class;
432    // typedef struct objc_object {
433    //  Class isa;
434    // } *id;
435
436    if (ObjTy)
437      return ObjTy;
438
439    if (!ClassTy)
440      ClassTy = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
441                                           "objc_class", TheCU,
442                                           getOrCreateMainFile(), 0);
443
444    unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
445
446    auto *ISATy = DBuilder.createPointerType(ClassTy, Size);
447
448    ObjTy =
449        DBuilder.createStructType(TheCU, "objc_object", getOrCreateMainFile(),
450                                  0, 0, 0, 0, nullptr, llvm::DINodeArray());
451
452    DBuilder.replaceArrays(
453        ObjTy,
454        DBuilder.getOrCreateArray(&*DBuilder.createMemberType(
455            ObjTy, "isa", getOrCreateMainFile(), 0, Size, 0, 0, 0, ISATy)));
456    return ObjTy;
457  }
458  case BuiltinType::ObjCSel: {
459    if (!SelTy)
460      SelTy = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
461                                         "objc_selector", TheCU,
462                                         getOrCreateMainFile(), 0);
463    return SelTy;
464  }
465
466  case BuiltinType::OCLImage1d:
467    return getOrCreateStructPtrType("opencl_image1d_t", OCLImage1dDITy);
468  case BuiltinType::OCLImage1dArray:
469    return getOrCreateStructPtrType("opencl_image1d_array_t",
470                                    OCLImage1dArrayDITy);
471  case BuiltinType::OCLImage1dBuffer:
472    return getOrCreateStructPtrType("opencl_image1d_buffer_t",
473                                    OCLImage1dBufferDITy);
474  case BuiltinType::OCLImage2d:
475    return getOrCreateStructPtrType("opencl_image2d_t", OCLImage2dDITy);
476  case BuiltinType::OCLImage2dArray:
477    return getOrCreateStructPtrType("opencl_image2d_array_t",
478                                    OCLImage2dArrayDITy);
479  case BuiltinType::OCLImage2dDepth:
480    return getOrCreateStructPtrType("opencl_image2d_depth_t",
481                                    OCLImage2dDepthDITy);
482  case BuiltinType::OCLImage2dArrayDepth:
483    return getOrCreateStructPtrType("opencl_image2d_array_depth_t",
484                                    OCLImage2dArrayDepthDITy);
485  case BuiltinType::OCLImage2dMSAA:
486    return getOrCreateStructPtrType("opencl_image2d_msaa_t",
487                                    OCLImage2dMSAADITy);
488  case BuiltinType::OCLImage2dArrayMSAA:
489    return getOrCreateStructPtrType("opencl_image2d_array_msaa_t",
490                                    OCLImage2dArrayMSAADITy);
491  case BuiltinType::OCLImage2dMSAADepth:
492    return getOrCreateStructPtrType("opencl_image2d_msaa_depth_t",
493                                    OCLImage2dMSAADepthDITy);
494  case BuiltinType::OCLImage2dArrayMSAADepth:
495    return getOrCreateStructPtrType("opencl_image2d_array_msaa_depth_t",
496                                    OCLImage2dArrayMSAADepthDITy);
497  case BuiltinType::OCLImage3d:
498    return getOrCreateStructPtrType("opencl_image3d_t", OCLImage3dDITy);
499  case BuiltinType::OCLSampler:
500    return DBuilder.createBasicType(
501        "opencl_sampler_t", CGM.getContext().getTypeSize(BT),
502        CGM.getContext().getTypeAlign(BT), llvm::dwarf::DW_ATE_unsigned);
503  case BuiltinType::OCLEvent:
504    return getOrCreateStructPtrType("opencl_event_t", OCLEventDITy);
505  case BuiltinType::OCLClkEvent:
506    return getOrCreateStructPtrType("opencl_clk_event_t", OCLClkEventDITy);
507  case BuiltinType::OCLQueue:
508    return getOrCreateStructPtrType("opencl_queue_t", OCLQueueDITy);
509  case BuiltinType::OCLNDRange:
510    return getOrCreateStructPtrType("opencl_ndrange_t", OCLNDRangeDITy);
511  case BuiltinType::OCLReserveID:
512    return getOrCreateStructPtrType("opencl_reserve_id_t", OCLReserveIDDITy);
513
514  case BuiltinType::UChar:
515  case BuiltinType::Char_U:
516    Encoding = llvm::dwarf::DW_ATE_unsigned_char;
517    break;
518  case BuiltinType::Char_S:
519  case BuiltinType::SChar:
520    Encoding = llvm::dwarf::DW_ATE_signed_char;
521    break;
522  case BuiltinType::Char16:
523  case BuiltinType::Char32:
524    Encoding = llvm::dwarf::DW_ATE_UTF;
525    break;
526  case BuiltinType::UShort:
527  case BuiltinType::UInt:
528  case BuiltinType::UInt128:
529  case BuiltinType::ULong:
530  case BuiltinType::WChar_U:
531  case BuiltinType::ULongLong:
532    Encoding = llvm::dwarf::DW_ATE_unsigned;
533    break;
534  case BuiltinType::Short:
535  case BuiltinType::Int:
536  case BuiltinType::Int128:
537  case BuiltinType::Long:
538  case BuiltinType::WChar_S:
539  case BuiltinType::LongLong:
540    Encoding = llvm::dwarf::DW_ATE_signed;
541    break;
542  case BuiltinType::Bool:
543    Encoding = llvm::dwarf::DW_ATE_boolean;
544    break;
545  case BuiltinType::Half:
546  case BuiltinType::Float:
547  case BuiltinType::LongDouble:
548  case BuiltinType::Double:
549    Encoding = llvm::dwarf::DW_ATE_float;
550    break;
551  }
552
553  switch (BT->getKind()) {
554  case BuiltinType::Long:
555    BTName = "long int";
556    break;
557  case BuiltinType::LongLong:
558    BTName = "long long int";
559    break;
560  case BuiltinType::ULong:
561    BTName = "long unsigned int";
562    break;
563  case BuiltinType::ULongLong:
564    BTName = "long long unsigned int";
565    break;
566  default:
567    BTName = BT->getName(CGM.getLangOpts());
568    break;
569  }
570  // Bit size, align and offset of the type.
571  uint64_t Size = CGM.getContext().getTypeSize(BT);
572  uint64_t Align = CGM.getContext().getTypeAlign(BT);
573  return DBuilder.createBasicType(BTName, Size, Align, Encoding);
574}
575
576llvm::DIType *CGDebugInfo::CreateType(const ComplexType *Ty) {
577  // Bit size, align and offset of the type.
578  llvm::dwarf::TypeKind Encoding = llvm::dwarf::DW_ATE_complex_float;
579  if (Ty->isComplexIntegerType())
580    Encoding = llvm::dwarf::DW_ATE_lo_user;
581
582  uint64_t Size = CGM.getContext().getTypeSize(Ty);
583  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
584  return DBuilder.createBasicType("complex", Size, Align, Encoding);
585}
586
587llvm::DIType *CGDebugInfo::CreateQualifiedType(QualType Ty,
588                                               llvm::DIFile *Unit) {
589  QualifierCollector Qc;
590  const Type *T = Qc.strip(Ty);
591
592  // Ignore these qualifiers for now.
593  Qc.removeObjCGCAttr();
594  Qc.removeAddressSpace();
595  Qc.removeObjCLifetime();
596
597  // We will create one Derived type for one qualifier and recurse to handle any
598  // additional ones.
599  llvm::dwarf::Tag Tag;
600  if (Qc.hasConst()) {
601    Tag = llvm::dwarf::DW_TAG_const_type;
602    Qc.removeConst();
603  } else if (Qc.hasVolatile()) {
604    Tag = llvm::dwarf::DW_TAG_volatile_type;
605    Qc.removeVolatile();
606  } else if (Qc.hasRestrict()) {
607    Tag = llvm::dwarf::DW_TAG_restrict_type;
608    Qc.removeRestrict();
609  } else {
610    assert(Qc.empty() && "Unknown type qualifier for debug info");
611    return getOrCreateType(QualType(T, 0), Unit);
612  }
613
614  auto *FromTy = getOrCreateType(Qc.apply(CGM.getContext(), T), Unit);
615
616  // No need to fill in the Name, Line, Size, Alignment, Offset in case of
617  // CVR derived types.
618  return DBuilder.createQualifiedType(Tag, FromTy);
619}
620
621llvm::DIType *CGDebugInfo::CreateType(const ObjCObjectPointerType *Ty,
622                                      llvm::DIFile *Unit) {
623
624  // The frontend treats 'id' as a typedef to an ObjCObjectType,
625  // whereas 'id<protocol>' is treated as an ObjCPointerType. For the
626  // debug info, we want to emit 'id' in both cases.
627  if (Ty->isObjCQualifiedIdType())
628    return getOrCreateType(CGM.getContext().getObjCIdType(), Unit);
629
630  return CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
631                               Ty->getPointeeType(), Unit);
632}
633
634llvm::DIType *CGDebugInfo::CreateType(const PointerType *Ty,
635                                      llvm::DIFile *Unit) {
636  return CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
637                               Ty->getPointeeType(), Unit);
638}
639
640/// \return whether a C++ mangling exists for the type defined by TD.
641static bool hasCXXMangling(const TagDecl *TD, llvm::DICompileUnit *TheCU) {
642  switch (TheCU->getSourceLanguage()) {
643  case llvm::dwarf::DW_LANG_C_plus_plus:
644    return true;
645  case llvm::dwarf::DW_LANG_ObjC_plus_plus:
646    return isa<CXXRecordDecl>(TD) || isa<EnumDecl>(TD);
647  default:
648    return false;
649  }
650}
651
652/// In C++ mode, types have linkage, so we can rely on the ODR and
653/// on their mangled names, if they're external.
654static SmallString<256> getUniqueTagTypeName(const TagType *Ty,
655                                             CodeGenModule &CGM,
656                                             llvm::DICompileUnit *TheCU) {
657  SmallString<256> FullName;
658  const TagDecl *TD = Ty->getDecl();
659
660  if (!hasCXXMangling(TD, TheCU) || !TD->isExternallyVisible())
661    return FullName;
662
663  // Microsoft Mangler does not have support for mangleCXXRTTIName yet.
664  if (CGM.getTarget().getCXXABI().isMicrosoft())
665    return FullName;
666
667  // TODO: This is using the RTTI name. Is there a better way to get
668  // a unique string for a type?
669  llvm::raw_svector_ostream Out(FullName);
670  CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(QualType(Ty, 0), Out);
671  return FullName;
672}
673
674/// \return the approproate DWARF tag for a composite type.
675static llvm::dwarf::Tag getTagForRecord(const RecordDecl *RD) {
676   llvm::dwarf::Tag Tag;
677  if (RD->isStruct() || RD->isInterface())
678    Tag = llvm::dwarf::DW_TAG_structure_type;
679  else if (RD->isUnion())
680    Tag = llvm::dwarf::DW_TAG_union_type;
681  else {
682    // FIXME: This could be a struct type giving a default visibility different
683    // than C++ class type, but needs llvm metadata changes first.
684    assert(RD->isClass());
685    Tag = llvm::dwarf::DW_TAG_class_type;
686  }
687  return Tag;
688}
689
690llvm::DICompositeType *
691CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty,
692                                      llvm::DIScope *Ctx) {
693  const RecordDecl *RD = Ty->getDecl();
694  if (llvm::DIType *T = getTypeOrNull(CGM.getContext().getRecordType(RD)))
695    return cast<llvm::DICompositeType>(T);
696  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
697  unsigned Line = getLineNumber(RD->getLocation());
698  StringRef RDName = getClassName(RD);
699
700  uint64_t Size = 0;
701  uint64_t Align = 0;
702
703  const RecordDecl *D = RD->getDefinition();
704  if (D && D->isCompleteDefinition()) {
705    Size = CGM.getContext().getTypeSize(Ty);
706    Align = CGM.getContext().getTypeAlign(Ty);
707  }
708
709  // Create the type.
710  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
711  llvm::DICompositeType *RetTy = DBuilder.createReplaceableCompositeType(
712      getTagForRecord(RD), RDName, Ctx, DefUnit, Line, 0, Size, Align,
713      llvm::DINode::FlagFwdDecl, FullName);
714  ReplaceMap.emplace_back(
715      std::piecewise_construct, std::make_tuple(Ty),
716      std::make_tuple(static_cast<llvm::Metadata *>(RetTy)));
717  return RetTy;
718}
719
720llvm::DIType *CGDebugInfo::CreatePointerLikeType(llvm::dwarf::Tag Tag,
721                                                 const Type *Ty,
722                                                 QualType PointeeTy,
723                                                 llvm::DIFile *Unit) {
724  // Bit size, align and offset of the type.
725  // Size is always the size of a pointer. We can't use getTypeSize here
726  // because that does not return the correct value for references.
727  unsigned AS = CGM.getContext().getTargetAddressSpace(PointeeTy);
728  uint64_t Size = CGM.getTarget().getPointerWidth(AS);
729  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
730
731  if (Tag == llvm::dwarf::DW_TAG_reference_type ||
732      Tag == llvm::dwarf::DW_TAG_rvalue_reference_type)
733    return DBuilder.createReferenceType(Tag, getOrCreateType(PointeeTy, Unit),
734                                        Size, Align);
735  else
736    return DBuilder.createPointerType(getOrCreateType(PointeeTy, Unit), Size,
737                                      Align);
738}
739
740llvm::DIType *CGDebugInfo::getOrCreateStructPtrType(StringRef Name,
741                                                    llvm::DIType *&Cache) {
742  if (Cache)
743    return Cache;
744  Cache = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type, Name,
745                                     TheCU, getOrCreateMainFile(), 0);
746  unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
747  Cache = DBuilder.createPointerType(Cache, Size);
748  return Cache;
749}
750
751llvm::DIType *CGDebugInfo::CreateType(const BlockPointerType *Ty,
752                                      llvm::DIFile *Unit) {
753  SmallVector<llvm::Metadata *, 8> EltTys;
754  QualType FType;
755  uint64_t FieldSize, FieldOffset;
756  unsigned FieldAlign;
757  llvm::DINodeArray Elements;
758
759  FieldOffset = 0;
760  FType = CGM.getContext().UnsignedLongTy;
761  EltTys.push_back(CreateMemberType(Unit, FType, "reserved", &FieldOffset));
762  EltTys.push_back(CreateMemberType(Unit, FType, "Size", &FieldOffset));
763
764  Elements = DBuilder.getOrCreateArray(EltTys);
765  EltTys.clear();
766
767  unsigned Flags = llvm::DINode::FlagAppleBlock;
768  unsigned LineNo = 0;
769
770  auto *EltTy =
771      DBuilder.createStructType(Unit, "__block_descriptor", nullptr, LineNo,
772                                FieldOffset, 0, Flags, nullptr, Elements);
773
774  // Bit size, align and offset of the type.
775  uint64_t Size = CGM.getContext().getTypeSize(Ty);
776
777  auto *DescTy = DBuilder.createPointerType(EltTy, Size);
778
779  FieldOffset = 0;
780  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
781  EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
782  FType = CGM.getContext().IntTy;
783  EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
784  EltTys.push_back(CreateMemberType(Unit, FType, "__reserved", &FieldOffset));
785  FType = CGM.getContext().getPointerType(Ty->getPointeeType());
786  EltTys.push_back(CreateMemberType(Unit, FType, "__FuncPtr", &FieldOffset));
787
788  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
789  FieldSize = CGM.getContext().getTypeSize(Ty);
790  FieldAlign = CGM.getContext().getTypeAlign(Ty);
791  EltTys.push_back(DBuilder.createMemberType(Unit, "__descriptor", nullptr, LineNo,
792                                             FieldSize, FieldAlign, FieldOffset,
793                                             0, DescTy));
794
795  FieldOffset += FieldSize;
796  Elements = DBuilder.getOrCreateArray(EltTys);
797
798  // The __block_literal_generic structs are marked with a special
799  // DW_AT_APPLE_BLOCK attribute and are an implementation detail only
800  // the debugger needs to know about. To allow type uniquing, emit
801  // them without a name or a location.
802  EltTy =
803      DBuilder.createStructType(Unit, "", nullptr, LineNo,
804                                FieldOffset, 0, Flags, nullptr, Elements);
805
806  return DBuilder.createPointerType(EltTy, Size);
807}
808
809llvm::DIType *CGDebugInfo::CreateType(const TemplateSpecializationType *Ty,
810                                      llvm::DIFile *Unit) {
811  assert(Ty->isTypeAlias());
812  llvm::DIType *Src = getOrCreateType(Ty->getAliasedType(), Unit);
813
814  SmallString<128> NS;
815  llvm::raw_svector_ostream OS(NS);
816  Ty->getTemplateName().print(OS, CGM.getContext().getPrintingPolicy(),
817                              /*qualified*/ false);
818
819  TemplateSpecializationType::PrintTemplateArgumentList(
820      OS, Ty->getArgs(), Ty->getNumArgs(),
821      CGM.getContext().getPrintingPolicy());
822
823  TypeAliasDecl *AliasDecl = cast<TypeAliasTemplateDecl>(
824      Ty->getTemplateName().getAsTemplateDecl())->getTemplatedDecl();
825
826  SourceLocation Loc = AliasDecl->getLocation();
827  return DBuilder.createTypedef(Src, OS.str(), getOrCreateFile(Loc),
828                                getLineNumber(Loc),
829                                getDeclContextDescriptor(AliasDecl));
830}
831
832llvm::DIType *CGDebugInfo::CreateType(const TypedefType *Ty,
833                                      llvm::DIFile *Unit) {
834  // We don't set size information, but do specify where the typedef was
835  // declared.
836  SourceLocation Loc = Ty->getDecl()->getLocation();
837
838  // Typedefs are derived from some other type.
839  return DBuilder.createTypedef(
840      getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit),
841      Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc),
842      getDeclContextDescriptor(Ty->getDecl()));
843}
844
845llvm::DIType *CGDebugInfo::CreateType(const FunctionType *Ty,
846                                      llvm::DIFile *Unit) {
847  SmallVector<llvm::Metadata *, 16> EltTys;
848
849  // Add the result type at least.
850  EltTys.push_back(getOrCreateType(Ty->getReturnType(), Unit));
851
852  // Set up remainder of arguments if there is a prototype.
853  // otherwise emit it as a variadic function.
854  if (isa<FunctionNoProtoType>(Ty))
855    EltTys.push_back(DBuilder.createUnspecifiedParameter());
856  else if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(Ty)) {
857    for (unsigned i = 0, e = FPT->getNumParams(); i != e; ++i)
858      EltTys.push_back(getOrCreateType(FPT->getParamType(i), Unit));
859    if (FPT->isVariadic())
860      EltTys.push_back(DBuilder.createUnspecifiedParameter());
861  }
862
863  llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(EltTys);
864  return DBuilder.createSubroutineType(EltTypeArray);
865}
866
867/// Convert an AccessSpecifier into the corresponding DINode flag.
868/// As an optimization, return 0 if the access specifier equals the
869/// default for the containing type.
870static unsigned getAccessFlag(AccessSpecifier Access, const RecordDecl *RD) {
871  AccessSpecifier Default = clang::AS_none;
872  if (RD && RD->isClass())
873    Default = clang::AS_private;
874  else if (RD && (RD->isStruct() || RD->isUnion()))
875    Default = clang::AS_public;
876
877  if (Access == Default)
878    return 0;
879
880  switch (Access) {
881  case clang::AS_private:
882    return llvm::DINode::FlagPrivate;
883  case clang::AS_protected:
884    return llvm::DINode::FlagProtected;
885  case clang::AS_public:
886    return llvm::DINode::FlagPublic;
887  case clang::AS_none:
888    return 0;
889  }
890  llvm_unreachable("unexpected access enumerator");
891}
892
893llvm::DIType *CGDebugInfo::createFieldType(
894    StringRef name, QualType type, uint64_t sizeInBitsOverride,
895    SourceLocation loc, AccessSpecifier AS, uint64_t offsetInBits,
896    llvm::DIFile *tunit, llvm::DIScope *scope, const RecordDecl *RD) {
897  llvm::DIType *debugType = getOrCreateType(type, tunit);
898
899  // Get the location for the field.
900  llvm::DIFile *file = getOrCreateFile(loc);
901  unsigned line = getLineNumber(loc);
902
903  uint64_t SizeInBits = 0;
904  unsigned AlignInBits = 0;
905  if (!type->isIncompleteArrayType()) {
906    TypeInfo TI = CGM.getContext().getTypeInfo(type);
907    SizeInBits = TI.Width;
908    AlignInBits = TI.Align;
909
910    if (sizeInBitsOverride)
911      SizeInBits = sizeInBitsOverride;
912  }
913
914  unsigned flags = getAccessFlag(AS, RD);
915  return DBuilder.createMemberType(scope, name, file, line, SizeInBits,
916                                   AlignInBits, offsetInBits, flags, debugType);
917}
918
919void CGDebugInfo::CollectRecordLambdaFields(
920    const CXXRecordDecl *CXXDecl, SmallVectorImpl<llvm::Metadata *> &elements,
921    llvm::DIType *RecordTy) {
922  // For C++11 Lambdas a Field will be the same as a Capture, but the Capture
923  // has the name and the location of the variable so we should iterate over
924  // both concurrently.
925  const ASTRecordLayout &layout = CGM.getContext().getASTRecordLayout(CXXDecl);
926  RecordDecl::field_iterator Field = CXXDecl->field_begin();
927  unsigned fieldno = 0;
928  for (CXXRecordDecl::capture_const_iterator I = CXXDecl->captures_begin(),
929                                             E = CXXDecl->captures_end();
930       I != E; ++I, ++Field, ++fieldno) {
931    const LambdaCapture &C = *I;
932    if (C.capturesVariable()) {
933      VarDecl *V = C.getCapturedVar();
934      llvm::DIFile *VUnit = getOrCreateFile(C.getLocation());
935      StringRef VName = V->getName();
936      uint64_t SizeInBitsOverride = 0;
937      if (Field->isBitField()) {
938        SizeInBitsOverride = Field->getBitWidthValue(CGM.getContext());
939        assert(SizeInBitsOverride && "found named 0-width bitfield");
940      }
941      llvm::DIType *fieldType = createFieldType(
942          VName, Field->getType(), SizeInBitsOverride, C.getLocation(),
943          Field->getAccess(), layout.getFieldOffset(fieldno), VUnit, RecordTy,
944          CXXDecl);
945      elements.push_back(fieldType);
946    } else if (C.capturesThis()) {
947      // TODO: Need to handle 'this' in some way by probably renaming the
948      // this of the lambda class and having a field member of 'this' or
949      // by using AT_object_pointer for the function and having that be
950      // used as 'this' for semantic references.
951      FieldDecl *f = *Field;
952      llvm::DIFile *VUnit = getOrCreateFile(f->getLocation());
953      QualType type = f->getType();
954      llvm::DIType *fieldType = createFieldType(
955          "this", type, 0, f->getLocation(), f->getAccess(),
956          layout.getFieldOffset(fieldno), VUnit, RecordTy, CXXDecl);
957
958      elements.push_back(fieldType);
959    }
960  }
961}
962
963llvm::DIDerivedType *
964CGDebugInfo::CreateRecordStaticField(const VarDecl *Var, llvm::DIType *RecordTy,
965                                     const RecordDecl *RD) {
966  // Create the descriptor for the static variable, with or without
967  // constant initializers.
968  Var = Var->getCanonicalDecl();
969  llvm::DIFile *VUnit = getOrCreateFile(Var->getLocation());
970  llvm::DIType *VTy = getOrCreateType(Var->getType(), VUnit);
971
972  unsigned LineNumber = getLineNumber(Var->getLocation());
973  StringRef VName = Var->getName();
974  llvm::Constant *C = nullptr;
975  if (Var->getInit()) {
976    const APValue *Value = Var->evaluateValue();
977    if (Value) {
978      if (Value->isInt())
979        C = llvm::ConstantInt::get(CGM.getLLVMContext(), Value->getInt());
980      if (Value->isFloat())
981        C = llvm::ConstantFP::get(CGM.getLLVMContext(), Value->getFloat());
982    }
983  }
984
985  unsigned Flags = getAccessFlag(Var->getAccess(), RD);
986  llvm::DIDerivedType *GV = DBuilder.createStaticMemberType(
987      RecordTy, VName, VUnit, LineNumber, VTy, Flags, C);
988  StaticDataMemberCache[Var->getCanonicalDecl()].reset(GV);
989  return GV;
990}
991
992void CGDebugInfo::CollectRecordNormalField(
993    const FieldDecl *field, uint64_t OffsetInBits, llvm::DIFile *tunit,
994    SmallVectorImpl<llvm::Metadata *> &elements, llvm::DIType *RecordTy,
995    const RecordDecl *RD) {
996  StringRef name = field->getName();
997  QualType type = field->getType();
998
999  // Ignore unnamed fields unless they're anonymous structs/unions.
1000  if (name.empty() && !type->isRecordType())
1001    return;
1002
1003  uint64_t SizeInBitsOverride = 0;
1004  if (field->isBitField()) {
1005    SizeInBitsOverride = field->getBitWidthValue(CGM.getContext());
1006    assert(SizeInBitsOverride && "found named 0-width bitfield");
1007  }
1008
1009  llvm::DIType *fieldType =
1010      createFieldType(name, type, SizeInBitsOverride, field->getLocation(),
1011                      field->getAccess(), OffsetInBits, tunit, RecordTy, RD);
1012
1013  elements.push_back(fieldType);
1014}
1015
1016void CGDebugInfo::CollectRecordFields(
1017    const RecordDecl *record, llvm::DIFile *tunit,
1018    SmallVectorImpl<llvm::Metadata *> &elements,
1019    llvm::DICompositeType *RecordTy) {
1020  const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(record);
1021
1022  if (CXXDecl && CXXDecl->isLambda())
1023    CollectRecordLambdaFields(CXXDecl, elements, RecordTy);
1024  else {
1025    const ASTRecordLayout &layout = CGM.getContext().getASTRecordLayout(record);
1026
1027    // Field number for non-static fields.
1028    unsigned fieldNo = 0;
1029
1030    // Static and non-static members should appear in the same order as
1031    // the corresponding declarations in the source program.
1032    for (const auto *I : record->decls())
1033      if (const auto *V = dyn_cast<VarDecl>(I)) {
1034        // Reuse the existing static member declaration if one exists
1035        auto MI = StaticDataMemberCache.find(V->getCanonicalDecl());
1036        if (MI != StaticDataMemberCache.end()) {
1037          assert(MI->second &&
1038                 "Static data member declaration should still exist");
1039          elements.push_back(MI->second);
1040        } else {
1041          auto Field = CreateRecordStaticField(V, RecordTy, record);
1042          elements.push_back(Field);
1043        }
1044      } else if (const auto *field = dyn_cast<FieldDecl>(I)) {
1045        CollectRecordNormalField(field, layout.getFieldOffset(fieldNo), tunit,
1046                                 elements, RecordTy, record);
1047
1048        // Bump field number for next field.
1049        ++fieldNo;
1050      }
1051  }
1052}
1053
1054llvm::DISubroutineType *
1055CGDebugInfo::getOrCreateMethodType(const CXXMethodDecl *Method,
1056                                   llvm::DIFile *Unit) {
1057  const FunctionProtoType *Func = Method->getType()->getAs<FunctionProtoType>();
1058  if (Method->isStatic())
1059    return cast_or_null<llvm::DISubroutineType>(
1060        getOrCreateType(QualType(Func, 0), Unit));
1061  return getOrCreateInstanceMethodType(Method->getThisType(CGM.getContext()),
1062                                       Func, Unit);
1063}
1064
1065llvm::DISubroutineType *CGDebugInfo::getOrCreateInstanceMethodType(
1066    QualType ThisPtr, const FunctionProtoType *Func, llvm::DIFile *Unit) {
1067  // Add "this" pointer.
1068  llvm::DITypeRefArray Args(
1069      cast<llvm::DISubroutineType>(getOrCreateType(QualType(Func, 0), Unit))
1070          ->getTypeArray());
1071  assert(Args.size() && "Invalid number of arguments!");
1072
1073  SmallVector<llvm::Metadata *, 16> Elts;
1074
1075  // First element is always return type. For 'void' functions it is NULL.
1076  Elts.push_back(Args[0]);
1077
1078  // "this" pointer is always first argument.
1079  const CXXRecordDecl *RD = ThisPtr->getPointeeCXXRecordDecl();
1080  if (isa<ClassTemplateSpecializationDecl>(RD)) {
1081    // Create pointer type directly in this case.
1082    const PointerType *ThisPtrTy = cast<PointerType>(ThisPtr);
1083    QualType PointeeTy = ThisPtrTy->getPointeeType();
1084    unsigned AS = CGM.getContext().getTargetAddressSpace(PointeeTy);
1085    uint64_t Size = CGM.getTarget().getPointerWidth(AS);
1086    uint64_t Align = CGM.getContext().getTypeAlign(ThisPtrTy);
1087    llvm::DIType *PointeeType = getOrCreateType(PointeeTy, Unit);
1088    llvm::DIType *ThisPtrType =
1089        DBuilder.createPointerType(PointeeType, Size, Align);
1090    TypeCache[ThisPtr.getAsOpaquePtr()].reset(ThisPtrType);
1091    // TODO: This and the artificial type below are misleading, the
1092    // types aren't artificial the argument is, but the current
1093    // metadata doesn't represent that.
1094    ThisPtrType = DBuilder.createObjectPointerType(ThisPtrType);
1095    Elts.push_back(ThisPtrType);
1096  } else {
1097    llvm::DIType *ThisPtrType = getOrCreateType(ThisPtr, Unit);
1098    TypeCache[ThisPtr.getAsOpaquePtr()].reset(ThisPtrType);
1099    ThisPtrType = DBuilder.createObjectPointerType(ThisPtrType);
1100    Elts.push_back(ThisPtrType);
1101  }
1102
1103  // Copy rest of the arguments.
1104  for (unsigned i = 1, e = Args.size(); i != e; ++i)
1105    Elts.push_back(Args[i]);
1106
1107  llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(Elts);
1108
1109  unsigned Flags = 0;
1110  if (Func->getExtProtoInfo().RefQualifier == RQ_LValue)
1111    Flags |= llvm::DINode::FlagLValueReference;
1112  if (Func->getExtProtoInfo().RefQualifier == RQ_RValue)
1113    Flags |= llvm::DINode::FlagRValueReference;
1114
1115  return DBuilder.createSubroutineType(EltTypeArray, Flags);
1116}
1117
1118/// isFunctionLocalClass - Return true if CXXRecordDecl is defined
1119/// inside a function.
1120static bool isFunctionLocalClass(const CXXRecordDecl *RD) {
1121  if (const CXXRecordDecl *NRD = dyn_cast<CXXRecordDecl>(RD->getDeclContext()))
1122    return isFunctionLocalClass(NRD);
1123  if (isa<FunctionDecl>(RD->getDeclContext()))
1124    return true;
1125  return false;
1126}
1127
1128llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
1129    const CXXMethodDecl *Method, llvm::DIFile *Unit, llvm::DIType *RecordTy) {
1130  bool IsCtorOrDtor =
1131      isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method);
1132
1133  StringRef MethodName = getFunctionName(Method);
1134  llvm::DISubroutineType *MethodTy = getOrCreateMethodType(Method, Unit);
1135
1136  // Since a single ctor/dtor corresponds to multiple functions, it doesn't
1137  // make sense to give a single ctor/dtor a linkage name.
1138  StringRef MethodLinkageName;
1139  if (!IsCtorOrDtor && !isFunctionLocalClass(Method->getParent()))
1140    MethodLinkageName = CGM.getMangledName(Method);
1141
1142  // Get the location for the method.
1143  llvm::DIFile *MethodDefUnit = nullptr;
1144  unsigned MethodLine = 0;
1145  if (!Method->isImplicit()) {
1146    MethodDefUnit = getOrCreateFile(Method->getLocation());
1147    MethodLine = getLineNumber(Method->getLocation());
1148  }
1149
1150  // Collect virtual method info.
1151  llvm::DIType *ContainingType = nullptr;
1152  unsigned Virtuality = 0;
1153  unsigned VIndex = 0;
1154
1155  if (Method->isVirtual()) {
1156    if (Method->isPure())
1157      Virtuality = llvm::dwarf::DW_VIRTUALITY_pure_virtual;
1158    else
1159      Virtuality = llvm::dwarf::DW_VIRTUALITY_virtual;
1160
1161    // It doesn't make sense to give a virtual destructor a vtable index,
1162    // since a single destructor has two entries in the vtable.
1163    // FIXME: Add proper support for debug info for virtual calls in
1164    // the Microsoft ABI, where we may use multiple vptrs to make a vftable
1165    // lookup if we have multiple or virtual inheritance.
1166    if (!isa<CXXDestructorDecl>(Method) &&
1167        !CGM.getTarget().getCXXABI().isMicrosoft())
1168      VIndex = CGM.getItaniumVTableContext().getMethodVTableIndex(Method);
1169    ContainingType = RecordTy;
1170  }
1171
1172  unsigned Flags = 0;
1173  if (Method->isImplicit())
1174    Flags |= llvm::DINode::FlagArtificial;
1175  Flags |= getAccessFlag(Method->getAccess(), Method->getParent());
1176  if (const CXXConstructorDecl *CXXC = dyn_cast<CXXConstructorDecl>(Method)) {
1177    if (CXXC->isExplicit())
1178      Flags |= llvm::DINode::FlagExplicit;
1179  } else if (const CXXConversionDecl *CXXC =
1180                 dyn_cast<CXXConversionDecl>(Method)) {
1181    if (CXXC->isExplicit())
1182      Flags |= llvm::DINode::FlagExplicit;
1183  }
1184  if (Method->hasPrototype())
1185    Flags |= llvm::DINode::FlagPrototyped;
1186  if (Method->getRefQualifier() == RQ_LValue)
1187    Flags |= llvm::DINode::FlagLValueReference;
1188  if (Method->getRefQualifier() == RQ_RValue)
1189    Flags |= llvm::DINode::FlagRValueReference;
1190
1191  llvm::DINodeArray TParamsArray = CollectFunctionTemplateParams(Method, Unit);
1192  llvm::DISubprogram *SP = DBuilder.createMethod(
1193      RecordTy, MethodName, MethodLinkageName, MethodDefUnit, MethodLine,
1194      MethodTy, /*isLocalToUnit=*/false,
1195      /* isDefinition=*/false, Virtuality, VIndex, ContainingType, Flags,
1196      CGM.getLangOpts().Optimize, TParamsArray.get());
1197
1198  SPCache[Method->getCanonicalDecl()].reset(SP);
1199
1200  return SP;
1201}
1202
1203void CGDebugInfo::CollectCXXMemberFunctions(
1204    const CXXRecordDecl *RD, llvm::DIFile *Unit,
1205    SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy) {
1206
1207  // Since we want more than just the individual member decls if we
1208  // have templated functions iterate over every declaration to gather
1209  // the functions.
1210  for (const auto *I : RD->decls()) {
1211    const auto *Method = dyn_cast<CXXMethodDecl>(I);
1212    // If the member is implicit, don't add it to the member list. This avoids
1213    // the member being added to type units by LLVM, while still allowing it
1214    // to be emitted into the type declaration/reference inside the compile
1215    // unit.
1216    // Ditto 'nodebug' methods, for consistency with CodeGenFunction.cpp.
1217    // FIXME: Handle Using(Shadow?)Decls here to create
1218    // DW_TAG_imported_declarations inside the class for base decls brought into
1219    // derived classes. GDB doesn't seem to notice/leverage these when I tried
1220    // it, so I'm not rushing to fix this. (GCC seems to produce them, if
1221    // referenced)
1222    if (!Method || Method->isImplicit() || Method->hasAttr<NoDebugAttr>())
1223      continue;
1224
1225    if (Method->getType()->getAs<FunctionProtoType>()->getContainedAutoType())
1226      continue;
1227
1228    // Reuse the existing member function declaration if it exists.
1229    // It may be associated with the declaration of the type & should be
1230    // reused as we're building the definition.
1231    //
1232    // This situation can arise in the vtable-based debug info reduction where
1233    // implicit members are emitted in a non-vtable TU.
1234    auto MI = SPCache.find(Method->getCanonicalDecl());
1235    EltTys.push_back(MI == SPCache.end()
1236                         ? CreateCXXMemberFunction(Method, Unit, RecordTy)
1237                         : static_cast<llvm::Metadata *>(MI->second));
1238  }
1239}
1240
1241void CGDebugInfo::CollectCXXBases(const CXXRecordDecl *RD, llvm::DIFile *Unit,
1242                                  SmallVectorImpl<llvm::Metadata *> &EltTys,
1243                                  llvm::DIType *RecordTy) {
1244  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
1245  for (const auto &BI : RD->bases()) {
1246    unsigned BFlags = 0;
1247    uint64_t BaseOffset;
1248
1249    const CXXRecordDecl *Base =
1250        cast<CXXRecordDecl>(BI.getType()->getAs<RecordType>()->getDecl());
1251
1252    if (BI.isVirtual()) {
1253      if (CGM.getTarget().getCXXABI().isItaniumFamily()) {
1254        // virtual base offset offset is -ve. The code generator emits dwarf
1255        // expression where it expects +ve number.
1256        BaseOffset = 0 - CGM.getItaniumVTableContext()
1257                             .getVirtualBaseOffsetOffset(RD, Base)
1258                             .getQuantity();
1259      } else {
1260        // In the MS ABI, store the vbtable offset, which is analogous to the
1261        // vbase offset offset in Itanium.
1262        BaseOffset =
1263            4 * CGM.getMicrosoftVTableContext().getVBTableIndex(RD, Base);
1264      }
1265      BFlags = llvm::DINode::FlagVirtual;
1266    } else
1267      BaseOffset = CGM.getContext().toBits(RL.getBaseClassOffset(Base));
1268    // FIXME: Inconsistent units for BaseOffset. It is in bytes when
1269    // BI->isVirtual() and bits when not.
1270
1271    BFlags |= getAccessFlag(BI.getAccessSpecifier(), RD);
1272    llvm::DIType *DTy = DBuilder.createInheritance(
1273        RecordTy, getOrCreateType(BI.getType(), Unit), BaseOffset, BFlags);
1274    EltTys.push_back(DTy);
1275  }
1276}
1277
1278llvm::DINodeArray
1279CGDebugInfo::CollectTemplateParams(const TemplateParameterList *TPList,
1280                                   ArrayRef<TemplateArgument> TAList,
1281                                   llvm::DIFile *Unit) {
1282  SmallVector<llvm::Metadata *, 16> TemplateParams;
1283  for (unsigned i = 0, e = TAList.size(); i != e; ++i) {
1284    const TemplateArgument &TA = TAList[i];
1285    StringRef Name;
1286    if (TPList)
1287      Name = TPList->getParam(i)->getName();
1288    switch (TA.getKind()) {
1289    case TemplateArgument::Type: {
1290      llvm::DIType *TTy = getOrCreateType(TA.getAsType(), Unit);
1291      TemplateParams.push_back(
1292          DBuilder.createTemplateTypeParameter(TheCU, Name, TTy));
1293    } break;
1294    case TemplateArgument::Integral: {
1295      llvm::DIType *TTy = getOrCreateType(TA.getIntegralType(), Unit);
1296      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1297          TheCU, Name, TTy,
1298          llvm::ConstantInt::get(CGM.getLLVMContext(), TA.getAsIntegral())));
1299    } break;
1300    case TemplateArgument::Declaration: {
1301      const ValueDecl *D = TA.getAsDecl();
1302      QualType T = TA.getParamTypeForDecl().getDesugaredType(CGM.getContext());
1303      llvm::DIType *TTy = getOrCreateType(T, Unit);
1304      llvm::Constant *V = nullptr;
1305      const CXXMethodDecl *MD;
1306      // Variable pointer template parameters have a value that is the address
1307      // of the variable.
1308      if (const auto *VD = dyn_cast<VarDecl>(D))
1309        V = CGM.GetAddrOfGlobalVar(VD);
1310      // Member function pointers have special support for building them, though
1311      // this is currently unsupported in LLVM CodeGen.
1312      else if ((MD = dyn_cast<CXXMethodDecl>(D)) && MD->isInstance())
1313        V = CGM.getCXXABI().EmitMemberFunctionPointer(MD);
1314      else if (const auto *FD = dyn_cast<FunctionDecl>(D))
1315        V = CGM.GetAddrOfFunction(FD);
1316      // Member data pointers have special handling too to compute the fixed
1317      // offset within the object.
1318      else if (const auto *MPT = dyn_cast<MemberPointerType>(T.getTypePtr())) {
1319        // These five lines (& possibly the above member function pointer
1320        // handling) might be able to be refactored to use similar code in
1321        // CodeGenModule::getMemberPointerConstant
1322        uint64_t fieldOffset = CGM.getContext().getFieldOffset(D);
1323        CharUnits chars =
1324            CGM.getContext().toCharUnitsFromBits((int64_t)fieldOffset);
1325        V = CGM.getCXXABI().EmitMemberDataPointer(MPT, chars);
1326      }
1327      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1328          TheCU, Name, TTy,
1329          cast_or_null<llvm::Constant>(V->stripPointerCasts())));
1330    } break;
1331    case TemplateArgument::NullPtr: {
1332      QualType T = TA.getNullPtrType();
1333      llvm::DIType *TTy = getOrCreateType(T, Unit);
1334      llvm::Constant *V = nullptr;
1335      // Special case member data pointer null values since they're actually -1
1336      // instead of zero.
1337      if (const MemberPointerType *MPT =
1338              dyn_cast<MemberPointerType>(T.getTypePtr()))
1339        // But treat member function pointers as simple zero integers because
1340        // it's easier than having a special case in LLVM's CodeGen. If LLVM
1341        // CodeGen grows handling for values of non-null member function
1342        // pointers then perhaps we could remove this special case and rely on
1343        // EmitNullMemberPointer for member function pointers.
1344        if (MPT->isMemberDataPointer())
1345          V = CGM.getCXXABI().EmitNullMemberPointer(MPT);
1346      if (!V)
1347        V = llvm::ConstantInt::get(CGM.Int8Ty, 0);
1348      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1349          TheCU, Name, TTy, cast<llvm::Constant>(V)));
1350    } break;
1351    case TemplateArgument::Template:
1352      TemplateParams.push_back(DBuilder.createTemplateTemplateParameter(
1353          TheCU, Name, nullptr,
1354          TA.getAsTemplate().getAsTemplateDecl()->getQualifiedNameAsString()));
1355      break;
1356    case TemplateArgument::Pack:
1357      TemplateParams.push_back(DBuilder.createTemplateParameterPack(
1358          TheCU, Name, nullptr,
1359          CollectTemplateParams(nullptr, TA.getPackAsArray(), Unit)));
1360      break;
1361    case TemplateArgument::Expression: {
1362      const Expr *E = TA.getAsExpr();
1363      QualType T = E->getType();
1364      if (E->isGLValue())
1365        T = CGM.getContext().getLValueReferenceType(T);
1366      llvm::Constant *V = CGM.EmitConstantExpr(E, T);
1367      assert(V && "Expression in template argument isn't constant");
1368      llvm::DIType *TTy = getOrCreateType(T, Unit);
1369      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1370          TheCU, Name, TTy, cast<llvm::Constant>(V->stripPointerCasts())));
1371    } break;
1372    // And the following should never occur:
1373    case TemplateArgument::TemplateExpansion:
1374    case TemplateArgument::Null:
1375      llvm_unreachable(
1376          "These argument types shouldn't exist in concrete types");
1377    }
1378  }
1379  return DBuilder.getOrCreateArray(TemplateParams);
1380}
1381
1382llvm::DINodeArray
1383CGDebugInfo::CollectFunctionTemplateParams(const FunctionDecl *FD,
1384                                           llvm::DIFile *Unit) {
1385  if (FD->getTemplatedKind() ==
1386      FunctionDecl::TK_FunctionTemplateSpecialization) {
1387    const TemplateParameterList *TList = FD->getTemplateSpecializationInfo()
1388                                             ->getTemplate()
1389                                             ->getTemplateParameters();
1390    return CollectTemplateParams(
1391        TList, FD->getTemplateSpecializationArgs()->asArray(), Unit);
1392  }
1393  return llvm::DINodeArray();
1394}
1395
1396llvm::DINodeArray CGDebugInfo::CollectCXXTemplateParams(
1397    const ClassTemplateSpecializationDecl *TSpecial, llvm::DIFile *Unit) {
1398  // Always get the full list of parameters, not just the ones from
1399  // the specialization.
1400  TemplateParameterList *TPList =
1401      TSpecial->getSpecializedTemplate()->getTemplateParameters();
1402  const TemplateArgumentList &TAList = TSpecial->getTemplateArgs();
1403  return CollectTemplateParams(TPList, TAList.asArray(), Unit);
1404}
1405
1406llvm::DIType *CGDebugInfo::getOrCreateVTablePtrType(llvm::DIFile *Unit) {
1407  if (VTablePtrType)
1408    return VTablePtrType;
1409
1410  ASTContext &Context = CGM.getContext();
1411
1412  /* Function type */
1413  llvm::Metadata *STy = getOrCreateType(Context.IntTy, Unit);
1414  llvm::DITypeRefArray SElements = DBuilder.getOrCreateTypeArray(STy);
1415  llvm::DIType *SubTy = DBuilder.createSubroutineType(SElements);
1416  unsigned Size = Context.getTypeSize(Context.VoidPtrTy);
1417  llvm::DIType *vtbl_ptr_type =
1418      DBuilder.createPointerType(SubTy, Size, 0, "__vtbl_ptr_type");
1419  VTablePtrType = DBuilder.createPointerType(vtbl_ptr_type, Size);
1420  return VTablePtrType;
1421}
1422
1423StringRef CGDebugInfo::getVTableName(const CXXRecordDecl *RD) {
1424  // Copy the gdb compatible name on the side and use its reference.
1425  return internString("_vptr$", RD->getNameAsString());
1426}
1427
1428void CGDebugInfo::CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile *Unit,
1429                                    SmallVectorImpl<llvm::Metadata *> &EltTys) {
1430  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
1431
1432  // If there is a primary base then it will hold vtable info.
1433  if (RL.getPrimaryBase())
1434    return;
1435
1436  // If this class is not dynamic then there is not any vtable info to collect.
1437  if (!RD->isDynamicClass())
1438    return;
1439
1440  unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
1441  llvm::DIType *VPTR = DBuilder.createMemberType(
1442      Unit, getVTableName(RD), Unit, 0, Size, 0, 0,
1443      llvm::DINode::FlagArtificial, getOrCreateVTablePtrType(Unit));
1444  EltTys.push_back(VPTR);
1445}
1446
1447llvm::DIType *CGDebugInfo::getOrCreateRecordType(QualType RTy,
1448                                                 SourceLocation Loc) {
1449  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
1450  llvm::DIType *T = getOrCreateType(RTy, getOrCreateFile(Loc));
1451  return T;
1452}
1453
1454llvm::DIType *CGDebugInfo::getOrCreateInterfaceType(QualType D,
1455                                                    SourceLocation Loc) {
1456  return getOrCreateStandaloneType(D, Loc);
1457}
1458
1459llvm::DIType *CGDebugInfo::getOrCreateStandaloneType(QualType D,
1460                                                     SourceLocation Loc) {
1461  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
1462  assert(!D.isNull() && "null type");
1463  llvm::DIType *T = getOrCreateType(D, getOrCreateFile(Loc));
1464  assert(T && "could not create debug info for type");
1465
1466  // Composite types with UIDs were already retained by DIBuilder
1467  // because they are only referenced by name in the IR.
1468  if (auto *CTy = dyn_cast<llvm::DICompositeType>(T))
1469    if (!CTy->getIdentifier().empty())
1470      return T;
1471  RetainedTypes.push_back(D.getAsOpaquePtr());
1472  return T;
1473}
1474
1475void CGDebugInfo::completeType(const EnumDecl *ED) {
1476  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
1477    return;
1478  QualType Ty = CGM.getContext().getEnumType(ED);
1479  void *TyPtr = Ty.getAsOpaquePtr();
1480  auto I = TypeCache.find(TyPtr);
1481  if (I == TypeCache.end() || !cast<llvm::DIType>(I->second)->isForwardDecl())
1482    return;
1483  llvm::DIType *Res = CreateTypeDefinition(Ty->castAs<EnumType>());
1484  assert(!Res->isForwardDecl());
1485  TypeCache[TyPtr].reset(Res);
1486}
1487
1488void CGDebugInfo::completeType(const RecordDecl *RD) {
1489  if (DebugKind > CodeGenOptions::LimitedDebugInfo ||
1490      !CGM.getLangOpts().CPlusPlus)
1491    completeRequiredType(RD);
1492}
1493
1494void CGDebugInfo::completeRequiredType(const RecordDecl *RD) {
1495  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
1496    return;
1497
1498  if (const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD))
1499    if (CXXDecl->isDynamicClass())
1500      return;
1501
1502  if (DebugTypeExtRefs && RD->isFromASTFile())
1503    return;
1504
1505  QualType Ty = CGM.getContext().getRecordType(RD);
1506  llvm::DIType *T = getTypeOrNull(Ty);
1507  if (T && T->isForwardDecl())
1508    completeClassData(RD);
1509}
1510
1511void CGDebugInfo::completeClassData(const RecordDecl *RD) {
1512  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
1513    return;
1514  QualType Ty = CGM.getContext().getRecordType(RD);
1515  void *TyPtr = Ty.getAsOpaquePtr();
1516  auto I = TypeCache.find(TyPtr);
1517  if (I != TypeCache.end() && !cast<llvm::DIType>(I->second)->isForwardDecl())
1518    return;
1519  llvm::DIType *Res = CreateTypeDefinition(Ty->castAs<RecordType>());
1520  assert(!Res->isForwardDecl());
1521  TypeCache[TyPtr].reset(Res);
1522}
1523
1524static bool hasExplicitMemberDefinition(CXXRecordDecl::method_iterator I,
1525                                        CXXRecordDecl::method_iterator End) {
1526  for (; I != End; ++I)
1527    if (FunctionDecl *Tmpl = I->getInstantiatedFromMemberFunction())
1528      if (!Tmpl->isImplicit() && Tmpl->isThisDeclarationADefinition() &&
1529          !I->getMemberSpecializationInfo()->isExplicitSpecialization())
1530        return true;
1531  return false;
1532}
1533
1534static bool shouldOmitDefinition(CodeGenOptions::DebugInfoKind DebugKind,
1535                                 bool DebugTypeExtRefs,
1536                                 const RecordDecl *RD,
1537                                 const LangOptions &LangOpts) {
1538  // Does the type exist in an imported clang module?
1539  if (DebugTypeExtRefs && RD->isFromASTFile() && RD->getDefinition())
1540      return true;
1541
1542  if (DebugKind > CodeGenOptions::LimitedDebugInfo)
1543    return false;
1544
1545  if (!LangOpts.CPlusPlus)
1546    return false;
1547
1548  if (!RD->isCompleteDefinitionRequired())
1549    return true;
1550
1551  const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
1552
1553  if (!CXXDecl)
1554    return false;
1555
1556  if (CXXDecl->hasDefinition() && CXXDecl->isDynamicClass())
1557    return true;
1558
1559  TemplateSpecializationKind Spec = TSK_Undeclared;
1560  if (const ClassTemplateSpecializationDecl *SD =
1561          dyn_cast<ClassTemplateSpecializationDecl>(RD))
1562    Spec = SD->getSpecializationKind();
1563
1564  if (Spec == TSK_ExplicitInstantiationDeclaration &&
1565      hasExplicitMemberDefinition(CXXDecl->method_begin(),
1566                                  CXXDecl->method_end()))
1567    return true;
1568
1569  return false;
1570}
1571
1572llvm::DIType *CGDebugInfo::CreateType(const RecordType *Ty) {
1573  RecordDecl *RD = Ty->getDecl();
1574  llvm::DIType *T = cast_or_null<llvm::DIType>(getTypeOrNull(QualType(Ty, 0)));
1575  if (T || shouldOmitDefinition(DebugKind, DebugTypeExtRefs, RD,
1576                                CGM.getLangOpts())) {
1577    if (!T)
1578      T = getOrCreateRecordFwdDecl(Ty, getDeclContextDescriptor(RD));
1579    return T;
1580  }
1581
1582  return CreateTypeDefinition(Ty);
1583}
1584
1585llvm::DIType *CGDebugInfo::CreateTypeDefinition(const RecordType *Ty) {
1586  RecordDecl *RD = Ty->getDecl();
1587
1588  // Get overall information about the record type for the debug info.
1589  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
1590
1591  // Records and classes and unions can all be recursive.  To handle them, we
1592  // first generate a debug descriptor for the struct as a forward declaration.
1593  // Then (if it is a definition) we go through and get debug info for all of
1594  // its members.  Finally, we create a descriptor for the complete type (which
1595  // may refer to the forward decl if the struct is recursive) and replace all
1596  // uses of the forward declaration with the final definition.
1597  llvm::DICompositeType *FwdDecl = getOrCreateLimitedType(Ty, DefUnit);
1598
1599  const RecordDecl *D = RD->getDefinition();
1600  if (!D || !D->isCompleteDefinition())
1601    return FwdDecl;
1602
1603  if (const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD))
1604    CollectContainingType(CXXDecl, FwdDecl);
1605
1606  // Push the struct on region stack.
1607  LexicalBlockStack.emplace_back(&*FwdDecl);
1608  RegionMap[Ty->getDecl()].reset(FwdDecl);
1609
1610  // Convert all the elements.
1611  SmallVector<llvm::Metadata *, 16> EltTys;
1612  // what about nested types?
1613
1614  // Note: The split of CXXDecl information here is intentional, the
1615  // gdb tests will depend on a certain ordering at printout. The debug
1616  // information offsets are still correct if we merge them all together
1617  // though.
1618  const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
1619  if (CXXDecl) {
1620    CollectCXXBases(CXXDecl, DefUnit, EltTys, FwdDecl);
1621    CollectVTableInfo(CXXDecl, DefUnit, EltTys);
1622  }
1623
1624  // Collect data fields (including static variables and any initializers).
1625  CollectRecordFields(RD, DefUnit, EltTys, FwdDecl);
1626  if (CXXDecl)
1627    CollectCXXMemberFunctions(CXXDecl, DefUnit, EltTys, FwdDecl);
1628
1629  LexicalBlockStack.pop_back();
1630  RegionMap.erase(Ty->getDecl());
1631
1632  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
1633  DBuilder.replaceArrays(FwdDecl, Elements);
1634
1635  if (FwdDecl->isTemporary())
1636    FwdDecl =
1637        llvm::MDNode::replaceWithPermanent(llvm::TempDICompositeType(FwdDecl));
1638
1639  RegionMap[Ty->getDecl()].reset(FwdDecl);
1640  return FwdDecl;
1641}
1642
1643llvm::DIType *CGDebugInfo::CreateType(const ObjCObjectType *Ty,
1644                                      llvm::DIFile *Unit) {
1645  // Ignore protocols.
1646  return getOrCreateType(Ty->getBaseType(), Unit);
1647}
1648
1649/// \return true if Getter has the default name for the property PD.
1650static bool hasDefaultGetterName(const ObjCPropertyDecl *PD,
1651                                 const ObjCMethodDecl *Getter) {
1652  assert(PD);
1653  if (!Getter)
1654    return true;
1655
1656  assert(Getter->getDeclName().isObjCZeroArgSelector());
1657  return PD->getName() ==
1658         Getter->getDeclName().getObjCSelector().getNameForSlot(0);
1659}
1660
1661/// \return true if Setter has the default name for the property PD.
1662static bool hasDefaultSetterName(const ObjCPropertyDecl *PD,
1663                                 const ObjCMethodDecl *Setter) {
1664  assert(PD);
1665  if (!Setter)
1666    return true;
1667
1668  assert(Setter->getDeclName().isObjCOneArgSelector());
1669  return SelectorTable::constructSetterName(PD->getName()) ==
1670         Setter->getDeclName().getObjCSelector().getNameForSlot(0);
1671}
1672
1673llvm::DIType *CGDebugInfo::CreateType(const ObjCInterfaceType *Ty,
1674                                      llvm::DIFile *Unit) {
1675  ObjCInterfaceDecl *ID = Ty->getDecl();
1676  if (!ID)
1677    return nullptr;
1678
1679  // Return a forward declaration if this type was imported from a clang module.
1680  if (DebugTypeExtRefs && ID->isFromASTFile() && ID->getDefinition())
1681    return DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
1682                                      ID->getName(),
1683                                      getDeclContextDescriptor(ID), Unit, 0);
1684
1685  // Get overall information about the record type for the debug info.
1686  llvm::DIFile *DefUnit = getOrCreateFile(ID->getLocation());
1687  unsigned Line = getLineNumber(ID->getLocation());
1688  auto RuntimeLang =
1689      static_cast<llvm::dwarf::SourceLanguage>(TheCU->getSourceLanguage());
1690
1691  // If this is just a forward declaration return a special forward-declaration
1692  // debug type since we won't be able to lay out the entire type.
1693  ObjCInterfaceDecl *Def = ID->getDefinition();
1694  if (!Def || !Def->getImplementation()) {
1695    llvm::DIScope *Mod = getParentModuleOrNull(ID);
1696    llvm::DIType *FwdDecl = DBuilder.createReplaceableCompositeType(
1697        llvm::dwarf::DW_TAG_structure_type, ID->getName(), Mod ? Mod : TheCU,
1698        DefUnit, Line, RuntimeLang);
1699    ObjCInterfaceCache.push_back(ObjCInterfaceCacheEntry(Ty, FwdDecl, Unit));
1700    return FwdDecl;
1701  }
1702
1703  return CreateTypeDefinition(Ty, Unit);
1704}
1705
1706llvm::DIModule *
1707CGDebugInfo::getOrCreateModuleRef(ExternalASTSource::ASTSourceDescriptor Mod,
1708                                  bool CreateSkeletonCU) {
1709  // Use the Module pointer as the key into the cache. This is a
1710  // nullptr if the "Module" is a PCH, which is safe because we don't
1711  // support chained PCH debug info, so there can only be a single PCH.
1712  const Module *M = Mod.getModuleOrNull();
1713  auto ModRef = ModuleCache.find(M);
1714  if (ModRef != ModuleCache.end())
1715    return cast<llvm::DIModule>(ModRef->second);
1716
1717  // Macro definitions that were defined with "-D" on the command line.
1718  SmallString<128> ConfigMacros;
1719  {
1720    llvm::raw_svector_ostream OS(ConfigMacros);
1721    const auto &PPOpts = CGM.getPreprocessorOpts();
1722    unsigned I = 0;
1723    // Translate the macro definitions back into a commmand line.
1724    for (auto &M : PPOpts.Macros) {
1725      if (++I > 1)
1726        OS << " ";
1727      const std::string &Macro = M.first;
1728      bool Undef = M.second;
1729      OS << "\"-" << (Undef ? 'U' : 'D');
1730      for (char c : Macro)
1731        switch (c) {
1732        case '\\' : OS << "\\\\"; break;
1733        case '"'  : OS << "\\\""; break;
1734        default: OS << c;
1735        }
1736      OS << '\"';
1737    }
1738  }
1739
1740  bool IsRootModule = M ? !M->Parent : true;
1741  if (CreateSkeletonCU && IsRootModule) {
1742    llvm::DIBuilder DIB(CGM.getModule());
1743    DIB.createCompileUnit(TheCU->getSourceLanguage(), Mod.getModuleName(),
1744                          Mod.getPath(), TheCU->getProducer(), true,
1745                          StringRef(), 0, Mod.getASTFile(),
1746                          llvm::DIBuilder::FullDebug, Mod.getSignature());
1747    DIB.finalize();
1748  }
1749  llvm::DIModule *Parent =
1750      IsRootModule ? nullptr
1751                   : getOrCreateModuleRef(
1752                         ExternalASTSource::ASTSourceDescriptor(*M->Parent),
1753                         CreateSkeletonCU);
1754  llvm::DIModule *DIMod =
1755      DBuilder.createModule(Parent, Mod.getModuleName(), ConfigMacros,
1756                            Mod.getPath(), CGM.getHeaderSearchOpts().Sysroot);
1757  ModuleCache[M].reset(DIMod);
1758  return DIMod;
1759}
1760
1761llvm::DIType *CGDebugInfo::CreateTypeDefinition(const ObjCInterfaceType *Ty,
1762                                                llvm::DIFile *Unit) {
1763  ObjCInterfaceDecl *ID = Ty->getDecl();
1764  llvm::DIFile *DefUnit = getOrCreateFile(ID->getLocation());
1765  unsigned Line = getLineNumber(ID->getLocation());
1766  unsigned RuntimeLang = TheCU->getSourceLanguage();
1767
1768  // Bit size, align and offset of the type.
1769  uint64_t Size = CGM.getContext().getTypeSize(Ty);
1770  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
1771
1772  unsigned Flags = 0;
1773  if (ID->getImplementation())
1774    Flags |= llvm::DINode::FlagObjcClassComplete;
1775
1776  llvm::DIScope *Mod = getParentModuleOrNull(ID);
1777  llvm::DICompositeType *RealDecl = DBuilder.createStructType(
1778      Mod ? Mod : Unit, ID->getName(), DefUnit, Line, Size, Align, Flags,
1779      nullptr, llvm::DINodeArray(), RuntimeLang);
1780
1781  QualType QTy(Ty, 0);
1782  TypeCache[QTy.getAsOpaquePtr()].reset(RealDecl);
1783
1784  // Push the struct on region stack.
1785  LexicalBlockStack.emplace_back(RealDecl);
1786  RegionMap[Ty->getDecl()].reset(RealDecl);
1787
1788  // Convert all the elements.
1789  SmallVector<llvm::Metadata *, 16> EltTys;
1790
1791  ObjCInterfaceDecl *SClass = ID->getSuperClass();
1792  if (SClass) {
1793    llvm::DIType *SClassTy =
1794        getOrCreateType(CGM.getContext().getObjCInterfaceType(SClass), Unit);
1795    if (!SClassTy)
1796      return nullptr;
1797
1798    llvm::DIType *InhTag = DBuilder.createInheritance(RealDecl, SClassTy, 0, 0);
1799    EltTys.push_back(InhTag);
1800  }
1801
1802  // Create entries for all of the properties.
1803  auto AddProperty = [&](const ObjCPropertyDecl *PD) {
1804    SourceLocation Loc = PD->getLocation();
1805    llvm::DIFile *PUnit = getOrCreateFile(Loc);
1806    unsigned PLine = getLineNumber(Loc);
1807    ObjCMethodDecl *Getter = PD->getGetterMethodDecl();
1808    ObjCMethodDecl *Setter = PD->getSetterMethodDecl();
1809    llvm::MDNode *PropertyNode = DBuilder.createObjCProperty(
1810        PD->getName(), PUnit, PLine,
1811        hasDefaultGetterName(PD, Getter) ? ""
1812                                         : getSelectorName(PD->getGetterName()),
1813        hasDefaultSetterName(PD, Setter) ? ""
1814                                         : getSelectorName(PD->getSetterName()),
1815        PD->getPropertyAttributes(), getOrCreateType(PD->getType(), PUnit));
1816    EltTys.push_back(PropertyNode);
1817  };
1818  {
1819    llvm::SmallPtrSet<const IdentifierInfo*, 16> PropertySet;
1820    for (const ObjCCategoryDecl *ClassExt : ID->known_extensions())
1821      for (auto *PD : ClassExt->properties()) {
1822        PropertySet.insert(PD->getIdentifier());
1823        AddProperty(PD);
1824      }
1825    for (const auto *PD : ID->properties()) {
1826      // Don't emit duplicate metadata for properties that were already in a
1827      // class extension.
1828      if (!PropertySet.insert(PD->getIdentifier()).second)
1829        continue;
1830      AddProperty(PD);
1831    }
1832  }
1833
1834  const ASTRecordLayout &RL = CGM.getContext().getASTObjCInterfaceLayout(ID);
1835  unsigned FieldNo = 0;
1836  for (ObjCIvarDecl *Field = ID->all_declared_ivar_begin(); Field;
1837       Field = Field->getNextIvar(), ++FieldNo) {
1838    llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
1839    if (!FieldTy)
1840      return nullptr;
1841
1842    StringRef FieldName = Field->getName();
1843
1844    // Ignore unnamed fields.
1845    if (FieldName.empty())
1846      continue;
1847
1848    // Get the location for the field.
1849    llvm::DIFile *FieldDefUnit = getOrCreateFile(Field->getLocation());
1850    unsigned FieldLine = getLineNumber(Field->getLocation());
1851    QualType FType = Field->getType();
1852    uint64_t FieldSize = 0;
1853    unsigned FieldAlign = 0;
1854
1855    if (!FType->isIncompleteArrayType()) {
1856
1857      // Bit size, align and offset of the type.
1858      FieldSize = Field->isBitField()
1859                      ? Field->getBitWidthValue(CGM.getContext())
1860                      : CGM.getContext().getTypeSize(FType);
1861      FieldAlign = CGM.getContext().getTypeAlign(FType);
1862    }
1863
1864    uint64_t FieldOffset;
1865    if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
1866      // We don't know the runtime offset of an ivar if we're using the
1867      // non-fragile ABI.  For bitfields, use the bit offset into the first
1868      // byte of storage of the bitfield.  For other fields, use zero.
1869      if (Field->isBitField()) {
1870        FieldOffset =
1871            CGM.getObjCRuntime().ComputeBitfieldBitOffset(CGM, ID, Field);
1872        FieldOffset %= CGM.getContext().getCharWidth();
1873      } else {
1874        FieldOffset = 0;
1875      }
1876    } else {
1877      FieldOffset = RL.getFieldOffset(FieldNo);
1878    }
1879
1880    unsigned Flags = 0;
1881    if (Field->getAccessControl() == ObjCIvarDecl::Protected)
1882      Flags = llvm::DINode::FlagProtected;
1883    else if (Field->getAccessControl() == ObjCIvarDecl::Private)
1884      Flags = llvm::DINode::FlagPrivate;
1885    else if (Field->getAccessControl() == ObjCIvarDecl::Public)
1886      Flags = llvm::DINode::FlagPublic;
1887
1888    llvm::MDNode *PropertyNode = nullptr;
1889    if (ObjCImplementationDecl *ImpD = ID->getImplementation()) {
1890      if (ObjCPropertyImplDecl *PImpD =
1891              ImpD->FindPropertyImplIvarDecl(Field->getIdentifier())) {
1892        if (ObjCPropertyDecl *PD = PImpD->getPropertyDecl()) {
1893          SourceLocation Loc = PD->getLocation();
1894          llvm::DIFile *PUnit = getOrCreateFile(Loc);
1895          unsigned PLine = getLineNumber(Loc);
1896          ObjCMethodDecl *Getter = PD->getGetterMethodDecl();
1897          ObjCMethodDecl *Setter = PD->getSetterMethodDecl();
1898          PropertyNode = DBuilder.createObjCProperty(
1899              PD->getName(), PUnit, PLine,
1900              hasDefaultGetterName(PD, Getter) ? "" : getSelectorName(
1901                                                          PD->getGetterName()),
1902              hasDefaultSetterName(PD, Setter) ? "" : getSelectorName(
1903                                                          PD->getSetterName()),
1904              PD->getPropertyAttributes(),
1905              getOrCreateType(PD->getType(), PUnit));
1906        }
1907      }
1908    }
1909    FieldTy = DBuilder.createObjCIVar(FieldName, FieldDefUnit, FieldLine,
1910                                      FieldSize, FieldAlign, FieldOffset, Flags,
1911                                      FieldTy, PropertyNode);
1912    EltTys.push_back(FieldTy);
1913  }
1914
1915  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
1916  DBuilder.replaceArrays(RealDecl, Elements);
1917
1918  LexicalBlockStack.pop_back();
1919  return RealDecl;
1920}
1921
1922llvm::DIType *CGDebugInfo::CreateType(const VectorType *Ty,
1923                                      llvm::DIFile *Unit) {
1924  llvm::DIType *ElementTy = getOrCreateType(Ty->getElementType(), Unit);
1925  int64_t Count = Ty->getNumElements();
1926  if (Count == 0)
1927    // If number of elements are not known then this is an unbounded array.
1928    // Use Count == -1 to express such arrays.
1929    Count = -1;
1930
1931  llvm::Metadata *Subscript = DBuilder.getOrCreateSubrange(0, Count);
1932  llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscript);
1933
1934  uint64_t Size = CGM.getContext().getTypeSize(Ty);
1935  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
1936
1937  return DBuilder.createVectorType(Size, Align, ElementTy, SubscriptArray);
1938}
1939
1940llvm::DIType *CGDebugInfo::CreateType(const ArrayType *Ty, llvm::DIFile *Unit) {
1941  uint64_t Size;
1942  uint64_t Align;
1943
1944  // FIXME: make getTypeAlign() aware of VLAs and incomplete array types
1945  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(Ty)) {
1946    Size = 0;
1947    Align =
1948        CGM.getContext().getTypeAlign(CGM.getContext().getBaseElementType(VAT));
1949  } else if (Ty->isIncompleteArrayType()) {
1950    Size = 0;
1951    if (Ty->getElementType()->isIncompleteType())
1952      Align = 0;
1953    else
1954      Align = CGM.getContext().getTypeAlign(Ty->getElementType());
1955  } else if (Ty->isIncompleteType()) {
1956    Size = 0;
1957    Align = 0;
1958  } else {
1959    // Size and align of the whole array, not the element type.
1960    Size = CGM.getContext().getTypeSize(Ty);
1961    Align = CGM.getContext().getTypeAlign(Ty);
1962  }
1963
1964  // Add the dimensions of the array.  FIXME: This loses CV qualifiers from
1965  // interior arrays, do we care?  Why aren't nested arrays represented the
1966  // obvious/recursive way?
1967  SmallVector<llvm::Metadata *, 8> Subscripts;
1968  QualType EltTy(Ty, 0);
1969  while ((Ty = dyn_cast<ArrayType>(EltTy))) {
1970    // If the number of elements is known, then count is that number. Otherwise,
1971    // it's -1. This allows us to represent a subrange with an array of 0
1972    // elements, like this:
1973    //
1974    //   struct foo {
1975    //     int x[0];
1976    //   };
1977    int64_t Count = -1; // Count == -1 is an unbounded array.
1978    if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(Ty))
1979      Count = CAT->getSize().getZExtValue();
1980
1981    // FIXME: Verify this is right for VLAs.
1982    Subscripts.push_back(DBuilder.getOrCreateSubrange(0, Count));
1983    EltTy = Ty->getElementType();
1984  }
1985
1986  llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscripts);
1987
1988  return DBuilder.createArrayType(Size, Align, getOrCreateType(EltTy, Unit),
1989                                  SubscriptArray);
1990}
1991
1992llvm::DIType *CGDebugInfo::CreateType(const LValueReferenceType *Ty,
1993                                      llvm::DIFile *Unit) {
1994  return CreatePointerLikeType(llvm::dwarf::DW_TAG_reference_type, Ty,
1995                               Ty->getPointeeType(), Unit);
1996}
1997
1998llvm::DIType *CGDebugInfo::CreateType(const RValueReferenceType *Ty,
1999                                      llvm::DIFile *Unit) {
2000  return CreatePointerLikeType(llvm::dwarf::DW_TAG_rvalue_reference_type, Ty,
2001                               Ty->getPointeeType(), Unit);
2002}
2003
2004llvm::DIType *CGDebugInfo::CreateType(const MemberPointerType *Ty,
2005                                      llvm::DIFile *U) {
2006  uint64_t Size =
2007      !Ty->isIncompleteType() ? CGM.getContext().getTypeSize(Ty) : 0;
2008  llvm::DIType *ClassType = getOrCreateType(QualType(Ty->getClass(), 0), U);
2009  if (Ty->isMemberDataPointerType())
2010    return DBuilder.createMemberPointerType(
2011        getOrCreateType(Ty->getPointeeType(), U), ClassType, Size);
2012
2013  const FunctionProtoType *FPT =
2014      Ty->getPointeeType()->getAs<FunctionProtoType>();
2015  return DBuilder.createMemberPointerType(
2016      getOrCreateInstanceMethodType(CGM.getContext().getPointerType(QualType(
2017                                        Ty->getClass(), FPT->getTypeQuals())),
2018                                    FPT, U),
2019      ClassType, Size);
2020}
2021
2022llvm::DIType *CGDebugInfo::CreateType(const AtomicType *Ty, llvm::DIFile *U) {
2023  // Ignore the atomic wrapping
2024  // FIXME: What is the correct representation?
2025  return getOrCreateType(Ty->getValueType(), U);
2026}
2027
2028llvm::DIType* CGDebugInfo::CreateType(const PipeType *Ty,
2029                                     llvm::DIFile *U) {
2030  return getOrCreateType(Ty->getElementType(), U);
2031}
2032
2033llvm::DIType *CGDebugInfo::CreateEnumType(const EnumType *Ty) {
2034  const EnumDecl *ED = Ty->getDecl();
2035
2036  uint64_t Size = 0;
2037  uint64_t Align = 0;
2038  if (!ED->getTypeForDecl()->isIncompleteType()) {
2039    Size = CGM.getContext().getTypeSize(ED->getTypeForDecl());
2040    Align = CGM.getContext().getTypeAlign(ED->getTypeForDecl());
2041  }
2042
2043  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
2044
2045  bool isImportedFromModule =
2046      DebugTypeExtRefs && ED->isFromASTFile() && ED->getDefinition();
2047
2048  // If this is just a forward declaration, construct an appropriately
2049  // marked node and just return it.
2050  if (isImportedFromModule || !ED->getDefinition()) {
2051    llvm::DIScope *EDContext = getDeclContextDescriptor(ED);
2052    llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
2053    unsigned Line = getLineNumber(ED->getLocation());
2054    StringRef EDName = ED->getName();
2055    llvm::DIType *RetTy = DBuilder.createReplaceableCompositeType(
2056        llvm::dwarf::DW_TAG_enumeration_type, EDName, EDContext, DefUnit, Line,
2057        0, Size, Align, llvm::DINode::FlagFwdDecl, FullName);
2058    ReplaceMap.emplace_back(
2059        std::piecewise_construct, std::make_tuple(Ty),
2060        std::make_tuple(static_cast<llvm::Metadata *>(RetTy)));
2061    return RetTy;
2062  }
2063
2064  return CreateTypeDefinition(Ty);
2065}
2066
2067llvm::DIType *CGDebugInfo::CreateTypeDefinition(const EnumType *Ty) {
2068  const EnumDecl *ED = Ty->getDecl();
2069  uint64_t Size = 0;
2070  uint64_t Align = 0;
2071  if (!ED->getTypeForDecl()->isIncompleteType()) {
2072    Size = CGM.getContext().getTypeSize(ED->getTypeForDecl());
2073    Align = CGM.getContext().getTypeAlign(ED->getTypeForDecl());
2074  }
2075
2076  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
2077
2078  // Create elements for each enumerator.
2079  SmallVector<llvm::Metadata *, 16> Enumerators;
2080  ED = ED->getDefinition();
2081  for (const auto *Enum : ED->enumerators()) {
2082    Enumerators.push_back(DBuilder.createEnumerator(
2083        Enum->getName(), Enum->getInitVal().getSExtValue()));
2084  }
2085
2086  // Return a CompositeType for the enum itself.
2087  llvm::DINodeArray EltArray = DBuilder.getOrCreateArray(Enumerators);
2088
2089  llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
2090  unsigned Line = getLineNumber(ED->getLocation());
2091  llvm::DIScope *EnumContext = getDeclContextDescriptor(ED);
2092  llvm::DIType *ClassTy =
2093      ED->isFixed() ? getOrCreateType(ED->getIntegerType(), DefUnit) : nullptr;
2094  return DBuilder.createEnumerationType(EnumContext, ED->getName(), DefUnit,
2095                                        Line, Size, Align, EltArray, ClassTy,
2096                                        FullName);
2097}
2098
2099static QualType UnwrapTypeForDebugInfo(QualType T, const ASTContext &C) {
2100  Qualifiers Quals;
2101  do {
2102    Qualifiers InnerQuals = T.getLocalQualifiers();
2103    // Qualifiers::operator+() doesn't like it if you add a Qualifier
2104    // that is already there.
2105    Quals += Qualifiers::removeCommonQualifiers(Quals, InnerQuals);
2106    Quals += InnerQuals;
2107    QualType LastT = T;
2108    switch (T->getTypeClass()) {
2109    default:
2110      return C.getQualifiedType(T.getTypePtr(), Quals);
2111    case Type::TemplateSpecialization: {
2112      const auto *Spec = cast<TemplateSpecializationType>(T);
2113      if (Spec->isTypeAlias())
2114        return C.getQualifiedType(T.getTypePtr(), Quals);
2115      T = Spec->desugar();
2116      break;
2117    }
2118    case Type::TypeOfExpr:
2119      T = cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType();
2120      break;
2121    case Type::TypeOf:
2122      T = cast<TypeOfType>(T)->getUnderlyingType();
2123      break;
2124    case Type::Decltype:
2125      T = cast<DecltypeType>(T)->getUnderlyingType();
2126      break;
2127    case Type::UnaryTransform:
2128      T = cast<UnaryTransformType>(T)->getUnderlyingType();
2129      break;
2130    case Type::Attributed:
2131      T = cast<AttributedType>(T)->getEquivalentType();
2132      break;
2133    case Type::Elaborated:
2134      T = cast<ElaboratedType>(T)->getNamedType();
2135      break;
2136    case Type::Paren:
2137      T = cast<ParenType>(T)->getInnerType();
2138      break;
2139    case Type::SubstTemplateTypeParm:
2140      T = cast<SubstTemplateTypeParmType>(T)->getReplacementType();
2141      break;
2142    case Type::Auto:
2143      QualType DT = cast<AutoType>(T)->getDeducedType();
2144      assert(!DT.isNull() && "Undeduced types shouldn't reach here.");
2145      T = DT;
2146      break;
2147    }
2148
2149    assert(T != LastT && "Type unwrapping failed to unwrap!");
2150    (void)LastT;
2151  } while (true);
2152}
2153
2154llvm::DIType *CGDebugInfo::getTypeOrNull(QualType Ty) {
2155
2156  // Unwrap the type as needed for debug information.
2157  Ty = UnwrapTypeForDebugInfo(Ty, CGM.getContext());
2158
2159  auto it = TypeCache.find(Ty.getAsOpaquePtr());
2160  if (it != TypeCache.end()) {
2161    // Verify that the debug info still exists.
2162    if (llvm::Metadata *V = it->second)
2163      return cast<llvm::DIType>(V);
2164  }
2165
2166  return nullptr;
2167}
2168
2169void CGDebugInfo::completeTemplateDefinition(
2170    const ClassTemplateSpecializationDecl &SD) {
2171  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
2172    return;
2173
2174  completeClassData(&SD);
2175  // In case this type has no member function definitions being emitted, ensure
2176  // it is retained
2177  RetainedTypes.push_back(CGM.getContext().getRecordType(&SD).getAsOpaquePtr());
2178}
2179
2180llvm::DIType *CGDebugInfo::getOrCreateType(QualType Ty, llvm::DIFile *Unit) {
2181  if (Ty.isNull())
2182    return nullptr;
2183
2184  // Unwrap the type as needed for debug information.
2185  Ty = UnwrapTypeForDebugInfo(Ty, CGM.getContext());
2186
2187  if (auto *T = getTypeOrNull(Ty))
2188    return T;
2189
2190  llvm::DIType *Res = CreateTypeNode(Ty, Unit);
2191  void* TyPtr = Ty.getAsOpaquePtr();
2192
2193  // And update the type cache.
2194  TypeCache[TyPtr].reset(Res);
2195
2196  return Res;
2197}
2198
2199llvm::DIModule *CGDebugInfo::getParentModuleOrNull(const Decl *D) {
2200  // A forward declaration inside a module header does not belong to the module.
2201  if (isa<RecordDecl>(D) && !cast<RecordDecl>(D)->getDefinition())
2202    return nullptr;
2203  if (DebugTypeExtRefs && D->isFromASTFile()) {
2204    // Record a reference to an imported clang module or precompiled header.
2205    auto *Reader = CGM.getContext().getExternalSource();
2206    auto Idx = D->getOwningModuleID();
2207    auto Info = Reader->getSourceDescriptor(Idx);
2208    if (Info)
2209      return getOrCreateModuleRef(*Info, /*SkeletonCU=*/true);
2210  } else if (ClangModuleMap) {
2211    // We are building a clang module or a precompiled header.
2212    //
2213    // TODO: When D is a CXXRecordDecl or a C++ Enum, the ODR applies
2214    // and it wouldn't be necessary to specify the parent scope
2215    // because the type is already unique by definition (it would look
2216    // like the output of -fno-standalone-debug). On the other hand,
2217    // the parent scope helps a consumer to quickly locate the object
2218    // file where the type's definition is located, so it might be
2219    // best to make this behavior a command line or debugger tuning
2220    // option.
2221    FullSourceLoc Loc(D->getLocation(), CGM.getContext().getSourceManager());
2222    if (Module *M = ClangModuleMap->inferModuleFromLocation(Loc)) {
2223      auto Info = ExternalASTSource::ASTSourceDescriptor(*M);
2224      return getOrCreateModuleRef(Info, /*SkeletonCU=*/false);
2225    }
2226  }
2227
2228  return nullptr;
2229}
2230
2231llvm::DIType *CGDebugInfo::CreateTypeNode(QualType Ty, llvm::DIFile *Unit) {
2232  // Handle qualifiers, which recursively handles what they refer to.
2233  if (Ty.hasLocalQualifiers())
2234    return CreateQualifiedType(Ty, Unit);
2235
2236  // Work out details of type.
2237  switch (Ty->getTypeClass()) {
2238#define TYPE(Class, Base)
2239#define ABSTRACT_TYPE(Class, Base)
2240#define NON_CANONICAL_TYPE(Class, Base)
2241#define DEPENDENT_TYPE(Class, Base) case Type::Class:
2242#include "clang/AST/TypeNodes.def"
2243    llvm_unreachable("Dependent types cannot show up in debug information");
2244
2245  case Type::ExtVector:
2246  case Type::Vector:
2247    return CreateType(cast<VectorType>(Ty), Unit);
2248  case Type::ObjCObjectPointer:
2249    return CreateType(cast<ObjCObjectPointerType>(Ty), Unit);
2250  case Type::ObjCObject:
2251    return CreateType(cast<ObjCObjectType>(Ty), Unit);
2252  case Type::ObjCInterface:
2253    return CreateType(cast<ObjCInterfaceType>(Ty), Unit);
2254  case Type::Builtin:
2255    return CreateType(cast<BuiltinType>(Ty));
2256  case Type::Complex:
2257    return CreateType(cast<ComplexType>(Ty));
2258  case Type::Pointer:
2259    return CreateType(cast<PointerType>(Ty), Unit);
2260  case Type::Adjusted:
2261  case Type::Decayed:
2262    // Decayed and adjusted types use the adjusted type in LLVM and DWARF.
2263    return CreateType(
2264        cast<PointerType>(cast<AdjustedType>(Ty)->getAdjustedType()), Unit);
2265  case Type::BlockPointer:
2266    return CreateType(cast<BlockPointerType>(Ty), Unit);
2267  case Type::Typedef:
2268    return CreateType(cast<TypedefType>(Ty), Unit);
2269  case Type::Record:
2270    return CreateType(cast<RecordType>(Ty));
2271  case Type::Enum:
2272    return CreateEnumType(cast<EnumType>(Ty));
2273  case Type::FunctionProto:
2274  case Type::FunctionNoProto:
2275    return CreateType(cast<FunctionType>(Ty), Unit);
2276  case Type::ConstantArray:
2277  case Type::VariableArray:
2278  case Type::IncompleteArray:
2279    return CreateType(cast<ArrayType>(Ty), Unit);
2280
2281  case Type::LValueReference:
2282    return CreateType(cast<LValueReferenceType>(Ty), Unit);
2283  case Type::RValueReference:
2284    return CreateType(cast<RValueReferenceType>(Ty), Unit);
2285
2286  case Type::MemberPointer:
2287    return CreateType(cast<MemberPointerType>(Ty), Unit);
2288
2289  case Type::Atomic:
2290    return CreateType(cast<AtomicType>(Ty), Unit);
2291
2292  case Type::Pipe:
2293    return CreateType(cast<PipeType>(Ty), Unit);
2294
2295  case Type::TemplateSpecialization:
2296    return CreateType(cast<TemplateSpecializationType>(Ty), Unit);
2297
2298  case Type::Auto:
2299  case Type::Attributed:
2300  case Type::Elaborated:
2301  case Type::Paren:
2302  case Type::SubstTemplateTypeParm:
2303  case Type::TypeOfExpr:
2304  case Type::TypeOf:
2305  case Type::Decltype:
2306  case Type::UnaryTransform:
2307  case Type::PackExpansion:
2308    break;
2309  }
2310
2311  llvm_unreachable("type should have been unwrapped!");
2312}
2313
2314llvm::DICompositeType *CGDebugInfo::getOrCreateLimitedType(const RecordType *Ty,
2315                                                           llvm::DIFile *Unit) {
2316  QualType QTy(Ty, 0);
2317
2318  auto *T = cast_or_null<llvm::DICompositeType>(getTypeOrNull(QTy));
2319
2320  // We may have cached a forward decl when we could have created
2321  // a non-forward decl. Go ahead and create a non-forward decl
2322  // now.
2323  if (T && !T->isForwardDecl())
2324    return T;
2325
2326  // Otherwise create the type.
2327  llvm::DICompositeType *Res = CreateLimitedType(Ty);
2328
2329  // Propagate members from the declaration to the definition
2330  // CreateType(const RecordType*) will overwrite this with the members in the
2331  // correct order if the full type is needed.
2332  DBuilder.replaceArrays(Res, T ? T->getElements() : llvm::DINodeArray());
2333
2334  // And update the type cache.
2335  TypeCache[QTy.getAsOpaquePtr()].reset(Res);
2336  return Res;
2337}
2338
2339// TODO: Currently used for context chains when limiting debug info.
2340llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
2341  RecordDecl *RD = Ty->getDecl();
2342
2343  // Get overall information about the record type for the debug info.
2344  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
2345  unsigned Line = getLineNumber(RD->getLocation());
2346  StringRef RDName = getClassName(RD);
2347
2348  llvm::DIScope *RDContext = getDeclContextDescriptor(RD);
2349
2350  // If we ended up creating the type during the context chain construction,
2351  // just return that.
2352  auto *T = cast_or_null<llvm::DICompositeType>(
2353      getTypeOrNull(CGM.getContext().getRecordType(RD)));
2354  if (T && (!T->isForwardDecl() || !RD->getDefinition()))
2355    return T;
2356
2357  // If this is just a forward or incomplete declaration, construct an
2358  // appropriately marked node and just return it.
2359  const RecordDecl *D = RD->getDefinition();
2360  if (!D || !D->isCompleteDefinition())
2361    return getOrCreateRecordFwdDecl(Ty, RDContext);
2362
2363  uint64_t Size = CGM.getContext().getTypeSize(Ty);
2364  uint64_t Align = CGM.getContext().getTypeAlign(Ty);
2365
2366  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
2367
2368  llvm::DICompositeType *RealDecl = DBuilder.createReplaceableCompositeType(
2369      getTagForRecord(RD), RDName, RDContext, DefUnit, Line, 0, Size, Align, 0,
2370      FullName);
2371
2372  RegionMap[Ty->getDecl()].reset(RealDecl);
2373  TypeCache[QualType(Ty, 0).getAsOpaquePtr()].reset(RealDecl);
2374
2375  if (const ClassTemplateSpecializationDecl *TSpecial =
2376          dyn_cast<ClassTemplateSpecializationDecl>(RD))
2377    DBuilder.replaceArrays(RealDecl, llvm::DINodeArray(),
2378                           CollectCXXTemplateParams(TSpecial, DefUnit));
2379  return RealDecl;
2380}
2381
2382void CGDebugInfo::CollectContainingType(const CXXRecordDecl *RD,
2383                                        llvm::DICompositeType *RealDecl) {
2384  // A class's primary base or the class itself contains the vtable.
2385  llvm::DICompositeType *ContainingType = nullptr;
2386  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
2387  if (const CXXRecordDecl *PBase = RL.getPrimaryBase()) {
2388    // Seek non-virtual primary base root.
2389    while (1) {
2390      const ASTRecordLayout &BRL = CGM.getContext().getASTRecordLayout(PBase);
2391      const CXXRecordDecl *PBT = BRL.getPrimaryBase();
2392      if (PBT && !BRL.isPrimaryBaseVirtual())
2393        PBase = PBT;
2394      else
2395        break;
2396    }
2397    ContainingType = cast<llvm::DICompositeType>(
2398        getOrCreateType(QualType(PBase->getTypeForDecl(), 0),
2399                        getOrCreateFile(RD->getLocation())));
2400  } else if (RD->isDynamicClass())
2401    ContainingType = RealDecl;
2402
2403  DBuilder.replaceVTableHolder(RealDecl, ContainingType);
2404}
2405
2406llvm::DIType *CGDebugInfo::CreateMemberType(llvm::DIFile *Unit, QualType FType,
2407                                            StringRef Name, uint64_t *Offset) {
2408  llvm::DIType *FieldTy = CGDebugInfo::getOrCreateType(FType, Unit);
2409  uint64_t FieldSize = CGM.getContext().getTypeSize(FType);
2410  unsigned FieldAlign = CGM.getContext().getTypeAlign(FType);
2411  llvm::DIType *Ty = DBuilder.createMemberType(Unit, Name, Unit, 0, FieldSize,
2412                                               FieldAlign, *Offset, 0, FieldTy);
2413  *Offset += FieldSize;
2414  return Ty;
2415}
2416
2417void CGDebugInfo::collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
2418                                           StringRef &Name,
2419                                           StringRef &LinkageName,
2420                                           llvm::DIScope *&FDContext,
2421                                           llvm::DINodeArray &TParamsArray,
2422                                           unsigned &Flags) {
2423  const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
2424  Name = getFunctionName(FD);
2425  // Use mangled name as linkage name for C/C++ functions.
2426  if (FD->hasPrototype()) {
2427    LinkageName = CGM.getMangledName(GD);
2428    Flags |= llvm::DINode::FlagPrototyped;
2429  }
2430  // No need to replicate the linkage name if it isn't different from the
2431  // subprogram name, no need to have it at all unless coverage is enabled or
2432  // debug is set to more than just line tables.
2433  if (LinkageName == Name ||
2434      (!CGM.getCodeGenOpts().EmitGcovArcs &&
2435       !CGM.getCodeGenOpts().EmitGcovNotes &&
2436       DebugKind <= CodeGenOptions::DebugLineTablesOnly))
2437    LinkageName = StringRef();
2438
2439  if (DebugKind >= CodeGenOptions::LimitedDebugInfo) {
2440    if (const NamespaceDecl *NSDecl =
2441        dyn_cast_or_null<NamespaceDecl>(FD->getDeclContext()))
2442      FDContext = getOrCreateNameSpace(NSDecl);
2443    else if (const RecordDecl *RDecl =
2444             dyn_cast_or_null<RecordDecl>(FD->getDeclContext())) {
2445      llvm::DIScope *Mod = getParentModuleOrNull(RDecl);
2446      FDContext = getContextDescriptor(RDecl, Mod ? Mod : TheCU);
2447    }
2448    // Collect template parameters.
2449    TParamsArray = CollectFunctionTemplateParams(FD, Unit);
2450  }
2451}
2452
2453void CGDebugInfo::collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
2454                                      unsigned &LineNo, QualType &T,
2455                                      StringRef &Name, StringRef &LinkageName,
2456                                      llvm::DIScope *&VDContext) {
2457  Unit = getOrCreateFile(VD->getLocation());
2458  LineNo = getLineNumber(VD->getLocation());
2459
2460  setLocation(VD->getLocation());
2461
2462  T = VD->getType();
2463  if (T->isIncompleteArrayType()) {
2464    // CodeGen turns int[] into int[1] so we'll do the same here.
2465    llvm::APInt ConstVal(32, 1);
2466    QualType ET = CGM.getContext().getAsArrayType(T)->getElementType();
2467
2468    T = CGM.getContext().getConstantArrayType(ET, ConstVal,
2469                                              ArrayType::Normal, 0);
2470  }
2471
2472  Name = VD->getName();
2473  if (VD->getDeclContext() && !isa<FunctionDecl>(VD->getDeclContext()) &&
2474      !isa<ObjCMethodDecl>(VD->getDeclContext()))
2475    LinkageName = CGM.getMangledName(VD);
2476  if (LinkageName == Name)
2477    LinkageName = StringRef();
2478
2479  // Since we emit declarations (DW_AT_members) for static members, place the
2480  // definition of those static members in the namespace they were declared in
2481  // in the source code (the lexical decl context).
2482  // FIXME: Generalize this for even non-member global variables where the
2483  // declaration and definition may have different lexical decl contexts, once
2484  // we have support for emitting declarations of (non-member) global variables.
2485  const DeclContext *DC = VD->isStaticDataMember() ? VD->getLexicalDeclContext()
2486                                                   : VD->getDeclContext();
2487  // When a record type contains an in-line initialization of a static data
2488  // member, and the record type is marked as __declspec(dllexport), an implicit
2489  // definition of the member will be created in the record context.  DWARF
2490  // doesn't seem to have a nice way to describe this in a form that consumers
2491  // are likely to understand, so fake the "normal" situation of a definition
2492  // outside the class by putting it in the global scope.
2493  if (DC->isRecord())
2494    DC = CGM.getContext().getTranslationUnitDecl();
2495
2496 llvm::DIScope *Mod = getParentModuleOrNull(VD);
2497 VDContext = getContextDescriptor(cast<Decl>(DC), Mod ? Mod : TheCU);
2498}
2499
2500llvm::DISubprogram *
2501CGDebugInfo::getFunctionForwardDeclaration(const FunctionDecl *FD) {
2502  llvm::DINodeArray TParamsArray;
2503  StringRef Name, LinkageName;
2504  unsigned Flags = 0;
2505  SourceLocation Loc = FD->getLocation();
2506  llvm::DIFile *Unit = getOrCreateFile(Loc);
2507  llvm::DIScope *DContext = Unit;
2508  unsigned Line = getLineNumber(Loc);
2509
2510  collectFunctionDeclProps(FD, Unit, Name, LinkageName, DContext,
2511                           TParamsArray, Flags);
2512  // Build function type.
2513  SmallVector<QualType, 16> ArgTypes;
2514  for (const ParmVarDecl *Parm: FD->parameters())
2515    ArgTypes.push_back(Parm->getType());
2516  QualType FnType =
2517    CGM.getContext().getFunctionType(FD->getReturnType(), ArgTypes,
2518                                     FunctionProtoType::ExtProtoInfo());
2519  llvm::DISubprogram *SP = DBuilder.createTempFunctionFwdDecl(
2520      DContext, Name, LinkageName, Unit, Line,
2521      getOrCreateFunctionType(FD, FnType, Unit), !FD->isExternallyVisible(),
2522      /* isDefinition = */ false, 0, Flags, CGM.getLangOpts().Optimize,
2523      TParamsArray.get(), getFunctionDeclaration(FD));
2524  const FunctionDecl *CanonDecl = cast<FunctionDecl>(FD->getCanonicalDecl());
2525  FwdDeclReplaceMap.emplace_back(std::piecewise_construct,
2526                                 std::make_tuple(CanonDecl),
2527                                 std::make_tuple(SP));
2528  return SP;
2529}
2530
2531llvm::DIGlobalVariable *
2532CGDebugInfo::getGlobalVariableForwardDeclaration(const VarDecl *VD) {
2533  QualType T;
2534  StringRef Name, LinkageName;
2535  SourceLocation Loc = VD->getLocation();
2536  llvm::DIFile *Unit = getOrCreateFile(Loc);
2537  llvm::DIScope *DContext = Unit;
2538  unsigned Line = getLineNumber(Loc);
2539
2540  collectVarDeclProps(VD, Unit, Line, T, Name, LinkageName, DContext);
2541  auto *GV = DBuilder.createTempGlobalVariableFwdDecl(
2542      DContext, Name, LinkageName, Unit, Line, getOrCreateType(T, Unit),
2543      !VD->isExternallyVisible(), nullptr, nullptr);
2544  FwdDeclReplaceMap.emplace_back(
2545      std::piecewise_construct,
2546      std::make_tuple(cast<VarDecl>(VD->getCanonicalDecl())),
2547      std::make_tuple(static_cast<llvm::Metadata *>(GV)));
2548  return GV;
2549}
2550
2551llvm::DINode *CGDebugInfo::getDeclarationOrDefinition(const Decl *D) {
2552  // We only need a declaration (not a definition) of the type - so use whatever
2553  // we would otherwise do to get a type for a pointee. (forward declarations in
2554  // limited debug info, full definitions (if the type definition is available)
2555  // in unlimited debug info)
2556  if (const TypeDecl *TD = dyn_cast<TypeDecl>(D))
2557    return getOrCreateType(CGM.getContext().getTypeDeclType(TD),
2558                           getOrCreateFile(TD->getLocation()));
2559  auto I = DeclCache.find(D->getCanonicalDecl());
2560
2561  if (I != DeclCache.end())
2562    return dyn_cast_or_null<llvm::DINode>(I->second);
2563
2564  // No definition for now. Emit a forward definition that might be
2565  // merged with a potential upcoming definition.
2566  if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
2567    return getFunctionForwardDeclaration(FD);
2568  else if (const auto *VD = dyn_cast<VarDecl>(D))
2569    return getGlobalVariableForwardDeclaration(VD);
2570
2571  return nullptr;
2572}
2573
2574llvm::DISubprogram *CGDebugInfo::getFunctionDeclaration(const Decl *D) {
2575  if (!D || DebugKind <= CodeGenOptions::DebugLineTablesOnly)
2576    return nullptr;
2577
2578  const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
2579  if (!FD)
2580    return nullptr;
2581
2582  // Setup context.
2583  auto *S = getDeclContextDescriptor(D);
2584
2585  auto MI = SPCache.find(FD->getCanonicalDecl());
2586  if (MI == SPCache.end()) {
2587    if (const CXXMethodDecl *MD =
2588            dyn_cast<CXXMethodDecl>(FD->getCanonicalDecl())) {
2589      return CreateCXXMemberFunction(MD, getOrCreateFile(MD->getLocation()),
2590                                     cast<llvm::DICompositeType>(S));
2591    }
2592  }
2593  if (MI != SPCache.end()) {
2594    auto *SP = dyn_cast_or_null<llvm::DISubprogram>(MI->second);
2595    if (SP && !SP->isDefinition())
2596      return SP;
2597  }
2598
2599  for (auto NextFD : FD->redecls()) {
2600    auto MI = SPCache.find(NextFD->getCanonicalDecl());
2601    if (MI != SPCache.end()) {
2602      auto *SP = dyn_cast_or_null<llvm::DISubprogram>(MI->second);
2603      if (SP && !SP->isDefinition())
2604        return SP;
2605    }
2606  }
2607  return nullptr;
2608}
2609
2610// getOrCreateFunctionType - Construct type. If it is a c++ method, include
2611// implicit parameter "this".
2612llvm::DISubroutineType *CGDebugInfo::getOrCreateFunctionType(const Decl *D,
2613                                                             QualType FnType,
2614                                                             llvm::DIFile *F) {
2615  if (!D || DebugKind <= CodeGenOptions::DebugLineTablesOnly)
2616    // Create fake but valid subroutine type. Otherwise -verify would fail, and
2617    // subprogram DIE will miss DW_AT_decl_file and DW_AT_decl_line fields.
2618    return DBuilder.createSubroutineType(DBuilder.getOrCreateTypeArray(None));
2619
2620  if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
2621    return getOrCreateMethodType(Method, F);
2622  if (const ObjCMethodDecl *OMethod = dyn_cast<ObjCMethodDecl>(D)) {
2623    // Add "self" and "_cmd"
2624    SmallVector<llvm::Metadata *, 16> Elts;
2625
2626    // First element is always return type. For 'void' functions it is NULL.
2627    QualType ResultTy = OMethod->getReturnType();
2628
2629    // Replace the instancetype keyword with the actual type.
2630    if (ResultTy == CGM.getContext().getObjCInstanceType())
2631      ResultTy = CGM.getContext().getPointerType(
2632          QualType(OMethod->getClassInterface()->getTypeForDecl(), 0));
2633
2634    Elts.push_back(getOrCreateType(ResultTy, F));
2635    // "self" pointer is always first argument.
2636    QualType SelfDeclTy;
2637    if (auto *SelfDecl = OMethod->getSelfDecl())
2638      SelfDeclTy = SelfDecl->getType();
2639    else if (auto *FPT = dyn_cast<FunctionProtoType>(FnType))
2640      if (FPT->getNumParams() > 1)
2641        SelfDeclTy = FPT->getParamType(0);
2642    if (!SelfDeclTy.isNull())
2643      Elts.push_back(CreateSelfType(SelfDeclTy, getOrCreateType(SelfDeclTy, F)));
2644    // "_cmd" pointer is always second argument.
2645    Elts.push_back(DBuilder.createArtificialType(
2646        getOrCreateType(CGM.getContext().getObjCSelType(), F)));
2647    // Get rest of the arguments.
2648    for (const auto *PI : OMethod->params())
2649      Elts.push_back(getOrCreateType(PI->getType(), F));
2650    // Variadic methods need a special marker at the end of the type list.
2651    if (OMethod->isVariadic())
2652      Elts.push_back(DBuilder.createUnspecifiedParameter());
2653
2654    llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(Elts);
2655    return DBuilder.createSubroutineType(EltTypeArray);
2656  }
2657
2658  // Handle variadic function types; they need an additional
2659  // unspecified parameter.
2660  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
2661    if (FD->isVariadic()) {
2662      SmallVector<llvm::Metadata *, 16> EltTys;
2663      EltTys.push_back(getOrCreateType(FD->getReturnType(), F));
2664      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FnType))
2665        for (unsigned i = 0, e = FPT->getNumParams(); i != e; ++i)
2666          EltTys.push_back(getOrCreateType(FPT->getParamType(i), F));
2667      EltTys.push_back(DBuilder.createUnspecifiedParameter());
2668      llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(EltTys);
2669      return DBuilder.createSubroutineType(EltTypeArray);
2670    }
2671
2672  return cast<llvm::DISubroutineType>(getOrCreateType(FnType, F));
2673}
2674
2675void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
2676                                    SourceLocation ScopeLoc, QualType FnType,
2677                                    llvm::Function *Fn, CGBuilderTy &Builder) {
2678
2679  StringRef Name;
2680  StringRef LinkageName;
2681
2682  FnBeginRegionCount.push_back(LexicalBlockStack.size());
2683
2684  const Decl *D = GD.getDecl();
2685  bool HasDecl = (D != nullptr);
2686
2687  unsigned Flags = 0;
2688  llvm::DIFile *Unit = getOrCreateFile(Loc);
2689  llvm::DIScope *FDContext = Unit;
2690  llvm::DINodeArray TParamsArray;
2691  if (!HasDecl) {
2692    // Use llvm function name.
2693    LinkageName = Fn->getName();
2694  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2695    // If there is a subprogram for this function available then use it.
2696    auto FI = SPCache.find(FD->getCanonicalDecl());
2697    if (FI != SPCache.end()) {
2698      auto *SP = dyn_cast_or_null<llvm::DISubprogram>(FI->second);
2699      if (SP && SP->isDefinition()) {
2700        LexicalBlockStack.emplace_back(SP);
2701        RegionMap[D].reset(SP);
2702        return;
2703      }
2704    }
2705    collectFunctionDeclProps(GD, Unit, Name, LinkageName, FDContext,
2706                             TParamsArray, Flags);
2707  } else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) {
2708    Name = getObjCMethodName(OMD);
2709    Flags |= llvm::DINode::FlagPrototyped;
2710  } else {
2711    // Use llvm function name.
2712    Name = Fn->getName();
2713    Flags |= llvm::DINode::FlagPrototyped;
2714  }
2715  if (!Name.empty() && Name[0] == '\01')
2716    Name = Name.substr(1);
2717
2718  if (!HasDecl || D->isImplicit()) {
2719    Flags |= llvm::DINode::FlagArtificial;
2720    // Artificial functions without a location should not silently reuse CurLoc.
2721    if (Loc.isInvalid())
2722      CurLoc = SourceLocation();
2723  }
2724  unsigned LineNo = getLineNumber(Loc);
2725  unsigned ScopeLine = getLineNumber(ScopeLoc);
2726
2727  // FIXME: The function declaration we're constructing here is mostly reusing
2728  // declarations from CXXMethodDecl and not constructing new ones for arbitrary
2729  // FunctionDecls. When/if we fix this we can have FDContext be TheCU/null for
2730  // all subprograms instead of the actual context since subprogram definitions
2731  // are emitted as CU level entities by the backend.
2732  llvm::DISubprogram *SP = DBuilder.createFunction(
2733      FDContext, Name, LinkageName, Unit, LineNo,
2734      getOrCreateFunctionType(D, FnType, Unit), Fn->hasInternalLinkage(),
2735      true /*definition*/, ScopeLine, Flags, CGM.getLangOpts().Optimize,
2736      TParamsArray.get(), getFunctionDeclaration(D));
2737  Fn->setSubprogram(SP);
2738  // We might get here with a VarDecl in the case we're generating
2739  // code for the initialization of globals. Do not record these decls
2740  // as they will overwrite the actual VarDecl Decl in the cache.
2741  if (HasDecl && isa<FunctionDecl>(D))
2742    DeclCache[D->getCanonicalDecl()].reset(static_cast<llvm::Metadata *>(SP));
2743
2744  // Push the function onto the lexical block stack.
2745  LexicalBlockStack.emplace_back(SP);
2746
2747  if (HasDecl)
2748    RegionMap[D].reset(SP);
2749}
2750
2751void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
2752                                   QualType FnType) {
2753  StringRef Name;
2754  StringRef LinkageName;
2755
2756  const Decl *D = GD.getDecl();
2757  if (!D)
2758    return;
2759
2760  unsigned Flags = 0;
2761  llvm::DIFile *Unit = getOrCreateFile(Loc);
2762  llvm::DIScope *FDContext = getDeclContextDescriptor(D);
2763  llvm::DINodeArray TParamsArray;
2764  if (isa<FunctionDecl>(D)) {
2765    // If there is a DISubprogram for this function available then use it.
2766    collectFunctionDeclProps(GD, Unit, Name, LinkageName, FDContext,
2767                             TParamsArray, Flags);
2768  } else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) {
2769    Name = getObjCMethodName(OMD);
2770    Flags |= llvm::DINode::FlagPrototyped;
2771  } else {
2772    llvm_unreachable("not a function or ObjC method");
2773  }
2774  if (!Name.empty() && Name[0] == '\01')
2775    Name = Name.substr(1);
2776
2777  if (D->isImplicit()) {
2778    Flags |= llvm::DINode::FlagArtificial;
2779    // Artificial functions without a location should not silently reuse CurLoc.
2780    if (Loc.isInvalid())
2781      CurLoc = SourceLocation();
2782  }
2783  unsigned LineNo = getLineNumber(Loc);
2784  unsigned ScopeLine = 0;
2785
2786  DBuilder.createFunction(FDContext, Name, LinkageName, Unit, LineNo,
2787                          getOrCreateFunctionType(D, FnType, Unit),
2788                          false /*internalLinkage*/, true /*definition*/,
2789                          ScopeLine, Flags, CGM.getLangOpts().Optimize,
2790                          TParamsArray.get(), getFunctionDeclaration(D));
2791}
2792
2793void CGDebugInfo::EmitLocation(CGBuilderTy &Builder, SourceLocation Loc) {
2794  // Update our current location
2795  setLocation(Loc);
2796
2797  if (CurLoc.isInvalid() || CurLoc.isMacroID())
2798    return;
2799
2800  llvm::MDNode *Scope = LexicalBlockStack.back();
2801  Builder.SetCurrentDebugLocation(llvm::DebugLoc::get(
2802      getLineNumber(CurLoc), getColumnNumber(CurLoc), Scope));
2803}
2804
2805void CGDebugInfo::CreateLexicalBlock(SourceLocation Loc) {
2806  llvm::MDNode *Back = nullptr;
2807  if (!LexicalBlockStack.empty())
2808    Back = LexicalBlockStack.back().get();
2809  LexicalBlockStack.emplace_back(DBuilder.createLexicalBlock(
2810      cast<llvm::DIScope>(Back), getOrCreateFile(CurLoc), getLineNumber(CurLoc),
2811      getColumnNumber(CurLoc)));
2812}
2813
2814void CGDebugInfo::EmitLexicalBlockStart(CGBuilderTy &Builder,
2815                                        SourceLocation Loc) {
2816  // Set our current location.
2817  setLocation(Loc);
2818
2819  // Emit a line table change for the current location inside the new scope.
2820  Builder.SetCurrentDebugLocation(llvm::DebugLoc::get(
2821      getLineNumber(Loc), getColumnNumber(Loc), LexicalBlockStack.back()));
2822
2823  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
2824    return;
2825
2826  // Create a new lexical block and push it on the stack.
2827  CreateLexicalBlock(Loc);
2828}
2829
2830void CGDebugInfo::EmitLexicalBlockEnd(CGBuilderTy &Builder,
2831                                      SourceLocation Loc) {
2832  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
2833
2834  // Provide an entry in the line table for the end of the block.
2835  EmitLocation(Builder, Loc);
2836
2837  if (DebugKind <= CodeGenOptions::DebugLineTablesOnly)
2838    return;
2839
2840  LexicalBlockStack.pop_back();
2841}
2842
2843void CGDebugInfo::EmitFunctionEnd(CGBuilderTy &Builder) {
2844  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
2845  unsigned RCount = FnBeginRegionCount.back();
2846  assert(RCount <= LexicalBlockStack.size() && "Region stack mismatch");
2847
2848  // Pop all regions for this function.
2849  while (LexicalBlockStack.size() != RCount) {
2850    // Provide an entry in the line table for the end of the block.
2851    EmitLocation(Builder, CurLoc);
2852    LexicalBlockStack.pop_back();
2853  }
2854  FnBeginRegionCount.pop_back();
2855}
2856
2857llvm::DIType *CGDebugInfo::EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
2858                                                        uint64_t *XOffset) {
2859
2860  SmallVector<llvm::Metadata *, 5> EltTys;
2861  QualType FType;
2862  uint64_t FieldSize, FieldOffset;
2863  unsigned FieldAlign;
2864
2865  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
2866  QualType Type = VD->getType();
2867
2868  FieldOffset = 0;
2869  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
2870  EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
2871  EltTys.push_back(CreateMemberType(Unit, FType, "__forwarding", &FieldOffset));
2872  FType = CGM.getContext().IntTy;
2873  EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
2874  EltTys.push_back(CreateMemberType(Unit, FType, "__size", &FieldOffset));
2875
2876  bool HasCopyAndDispose = CGM.getContext().BlockRequiresCopying(Type, VD);
2877  if (HasCopyAndDispose) {
2878    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
2879    EltTys.push_back(
2880        CreateMemberType(Unit, FType, "__copy_helper", &FieldOffset));
2881    EltTys.push_back(
2882        CreateMemberType(Unit, FType, "__destroy_helper", &FieldOffset));
2883  }
2884  bool HasByrefExtendedLayout;
2885  Qualifiers::ObjCLifetime Lifetime;
2886  if (CGM.getContext().getByrefLifetime(Type, Lifetime,
2887                                        HasByrefExtendedLayout) &&
2888      HasByrefExtendedLayout) {
2889    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
2890    EltTys.push_back(
2891        CreateMemberType(Unit, FType, "__byref_variable_layout", &FieldOffset));
2892  }
2893
2894  CharUnits Align = CGM.getContext().getDeclAlign(VD);
2895  if (Align > CGM.getContext().toCharUnitsFromBits(
2896                  CGM.getTarget().getPointerAlign(0))) {
2897    CharUnits FieldOffsetInBytes =
2898        CGM.getContext().toCharUnitsFromBits(FieldOffset);
2899    CharUnits AlignedOffsetInBytes =
2900        FieldOffsetInBytes.RoundUpToAlignment(Align);
2901    CharUnits NumPaddingBytes = AlignedOffsetInBytes - FieldOffsetInBytes;
2902
2903    if (NumPaddingBytes.isPositive()) {
2904      llvm::APInt pad(32, NumPaddingBytes.getQuantity());
2905      FType = CGM.getContext().getConstantArrayType(CGM.getContext().CharTy,
2906                                                    pad, ArrayType::Normal, 0);
2907      EltTys.push_back(CreateMemberType(Unit, FType, "", &FieldOffset));
2908    }
2909  }
2910
2911  FType = Type;
2912  llvm::DIType *FieldTy = getOrCreateType(FType, Unit);
2913  FieldSize = CGM.getContext().getTypeSize(FType);
2914  FieldAlign = CGM.getContext().toBits(Align);
2915
2916  *XOffset = FieldOffset;
2917  FieldTy = DBuilder.createMemberType(Unit, VD->getName(), Unit, 0, FieldSize,
2918                                      FieldAlign, FieldOffset, 0, FieldTy);
2919  EltTys.push_back(FieldTy);
2920  FieldOffset += FieldSize;
2921
2922  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
2923
2924  unsigned Flags = llvm::DINode::FlagBlockByrefStruct;
2925
2926  return DBuilder.createStructType(Unit, "", Unit, 0, FieldOffset, 0, Flags,
2927                                   nullptr, Elements);
2928}
2929
2930void CGDebugInfo::EmitDeclare(const VarDecl *VD, llvm::Value *Storage,
2931                              llvm::Optional<unsigned> ArgNo,
2932                              CGBuilderTy &Builder) {
2933  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
2934  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
2935
2936  bool Unwritten =
2937      VD->isImplicit() || (isa<Decl>(VD->getDeclContext()) &&
2938                           cast<Decl>(VD->getDeclContext())->isImplicit());
2939  llvm::DIFile *Unit = nullptr;
2940  if (!Unwritten)
2941    Unit = getOrCreateFile(VD->getLocation());
2942  llvm::DIType *Ty;
2943  uint64_t XOffset = 0;
2944  if (VD->hasAttr<BlocksAttr>())
2945    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset);
2946  else
2947    Ty = getOrCreateType(VD->getType(), Unit);
2948
2949  // If there is no debug info for this type then do not emit debug info
2950  // for this variable.
2951  if (!Ty)
2952    return;
2953
2954  // Get location information.
2955  unsigned Line = 0;
2956  unsigned Column = 0;
2957  if (!Unwritten) {
2958    Line = getLineNumber(VD->getLocation());
2959    Column = getColumnNumber(VD->getLocation());
2960  }
2961  SmallVector<int64_t, 9> Expr;
2962  unsigned Flags = 0;
2963  if (VD->isImplicit())
2964    Flags |= llvm::DINode::FlagArtificial;
2965  // If this is the first argument and it is implicit then
2966  // give it an object pointer flag.
2967  // FIXME: There has to be a better way to do this, but for static
2968  // functions there won't be an implicit param at arg1 and
2969  // otherwise it is 'self' or 'this'.
2970  if (isa<ImplicitParamDecl>(VD) && ArgNo && *ArgNo == 1)
2971    Flags |= llvm::DINode::FlagObjectPointer;
2972  if (llvm::Argument *Arg = dyn_cast<llvm::Argument>(Storage))
2973    if (Arg->getType()->isPointerTy() && !Arg->hasByValAttr() &&
2974        !VD->getType()->isPointerType())
2975      Expr.push_back(llvm::dwarf::DW_OP_deref);
2976
2977  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
2978
2979  StringRef Name = VD->getName();
2980  if (!Name.empty()) {
2981    if (VD->hasAttr<BlocksAttr>()) {
2982      CharUnits offset = CharUnits::fromQuantity(32);
2983      Expr.push_back(llvm::dwarf::DW_OP_plus);
2984      // offset of __forwarding field
2985      offset = CGM.getContext().toCharUnitsFromBits(
2986          CGM.getTarget().getPointerWidth(0));
2987      Expr.push_back(offset.getQuantity());
2988      Expr.push_back(llvm::dwarf::DW_OP_deref);
2989      Expr.push_back(llvm::dwarf::DW_OP_plus);
2990      // offset of x field
2991      offset = CGM.getContext().toCharUnitsFromBits(XOffset);
2992      Expr.push_back(offset.getQuantity());
2993
2994      // Create the descriptor for the variable.
2995      auto *D = ArgNo
2996                    ? DBuilder.createParameterVariable(Scope, VD->getName(),
2997                                                       *ArgNo, Unit, Line, Ty)
2998                    : DBuilder.createAutoVariable(Scope, VD->getName(), Unit,
2999                                                  Line, Ty);
3000
3001      // Insert an llvm.dbg.declare into the current block.
3002      DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(Expr),
3003                             llvm::DebugLoc::get(Line, Column, Scope),
3004                             Builder.GetInsertBlock());
3005      return;
3006    } else if (isa<VariableArrayType>(VD->getType()))
3007      Expr.push_back(llvm::dwarf::DW_OP_deref);
3008  } else if (const RecordType *RT = dyn_cast<RecordType>(VD->getType())) {
3009    // If VD is an anonymous union then Storage represents value for
3010    // all union fields.
3011    const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
3012    if (RD->isUnion() && RD->isAnonymousStructOrUnion()) {
3013      // GDB has trouble finding local variables in anonymous unions, so we emit
3014      // artifical local variables for each of the members.
3015      //
3016      // FIXME: Remove this code as soon as GDB supports this.
3017      // The debug info verifier in LLVM operates based on the assumption that a
3018      // variable has the same size as its storage and we had to disable the check
3019      // for artificial variables.
3020      for (const auto *Field : RD->fields()) {
3021        llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
3022        StringRef FieldName = Field->getName();
3023
3024        // Ignore unnamed fields. Do not ignore unnamed records.
3025        if (FieldName.empty() && !isa<RecordType>(Field->getType()))
3026          continue;
3027
3028        // Use VarDecl's Tag, Scope and Line number.
3029        auto *D = DBuilder.createAutoVariable(
3030            Scope, FieldName, Unit, Line, FieldTy, CGM.getLangOpts().Optimize,
3031            Flags | llvm::DINode::FlagArtificial);
3032
3033        // Insert an llvm.dbg.declare into the current block.
3034        DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(Expr),
3035                               llvm::DebugLoc::get(Line, Column, Scope),
3036                               Builder.GetInsertBlock());
3037      }
3038    }
3039  }
3040
3041  // Create the descriptor for the variable.
3042  auto *D =
3043      ArgNo
3044          ? DBuilder.createParameterVariable(Scope, Name, *ArgNo, Unit, Line,
3045                                             Ty, CGM.getLangOpts().Optimize,
3046                                             Flags)
3047          : DBuilder.createAutoVariable(Scope, Name, Unit, Line, Ty,
3048                                        CGM.getLangOpts().Optimize, Flags);
3049
3050  // Insert an llvm.dbg.declare into the current block.
3051  DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(Expr),
3052                         llvm::DebugLoc::get(Line, Column, Scope),
3053                         Builder.GetInsertBlock());
3054}
3055
3056void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD,
3057                                            llvm::Value *Storage,
3058                                            CGBuilderTy &Builder) {
3059  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3060  EmitDeclare(VD, Storage, llvm::None, Builder);
3061}
3062
3063llvm::DIType *CGDebugInfo::CreateSelfType(const QualType &QualTy,
3064                                          llvm::DIType *Ty) {
3065  llvm::DIType *CachedTy = getTypeOrNull(QualTy);
3066  if (CachedTy)
3067    Ty = CachedTy;
3068  return DBuilder.createObjectPointerType(Ty);
3069}
3070
3071void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
3072    const VarDecl *VD, llvm::Value *Storage, CGBuilderTy &Builder,
3073    const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint) {
3074  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3075  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
3076
3077  if (Builder.GetInsertBlock() == nullptr)
3078    return;
3079
3080  bool isByRef = VD->hasAttr<BlocksAttr>();
3081
3082  uint64_t XOffset = 0;
3083  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
3084  llvm::DIType *Ty;
3085  if (isByRef)
3086    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset);
3087  else
3088    Ty = getOrCreateType(VD->getType(), Unit);
3089
3090  // Self is passed along as an implicit non-arg variable in a
3091  // block. Mark it as the object pointer.
3092  if (isa<ImplicitParamDecl>(VD) && VD->getName() == "self")
3093    Ty = CreateSelfType(VD->getType(), Ty);
3094
3095  // Get location information.
3096  unsigned Line = getLineNumber(VD->getLocation());
3097  unsigned Column = getColumnNumber(VD->getLocation());
3098
3099  const llvm::DataLayout &target = CGM.getDataLayout();
3100
3101  CharUnits offset = CharUnits::fromQuantity(
3102      target.getStructLayout(blockInfo.StructureType)
3103          ->getElementOffset(blockInfo.getCapture(VD).getIndex()));
3104
3105  SmallVector<int64_t, 9> addr;
3106  if (isa<llvm::AllocaInst>(Storage))
3107    addr.push_back(llvm::dwarf::DW_OP_deref);
3108  addr.push_back(llvm::dwarf::DW_OP_plus);
3109  addr.push_back(offset.getQuantity());
3110  if (isByRef) {
3111    addr.push_back(llvm::dwarf::DW_OP_deref);
3112    addr.push_back(llvm::dwarf::DW_OP_plus);
3113    // offset of __forwarding field
3114    offset =
3115        CGM.getContext().toCharUnitsFromBits(target.getPointerSizeInBits(0));
3116    addr.push_back(offset.getQuantity());
3117    addr.push_back(llvm::dwarf::DW_OP_deref);
3118    addr.push_back(llvm::dwarf::DW_OP_plus);
3119    // offset of x field
3120    offset = CGM.getContext().toCharUnitsFromBits(XOffset);
3121    addr.push_back(offset.getQuantity());
3122  }
3123
3124  // Create the descriptor for the variable.
3125  auto *D = DBuilder.createAutoVariable(
3126      cast<llvm::DILocalScope>(LexicalBlockStack.back()), VD->getName(), Unit,
3127      Line, Ty);
3128
3129  // Insert an llvm.dbg.declare into the current block.
3130  auto DL = llvm::DebugLoc::get(Line, Column, LexicalBlockStack.back());
3131  if (InsertPoint)
3132    DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(addr), DL,
3133                           InsertPoint);
3134  else
3135    DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(addr), DL,
3136                           Builder.GetInsertBlock());
3137}
3138
3139void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
3140                                           unsigned ArgNo,
3141                                           CGBuilderTy &Builder) {
3142  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3143  EmitDeclare(VD, AI, ArgNo, Builder);
3144}
3145
3146namespace {
3147struct BlockLayoutChunk {
3148  uint64_t OffsetInBits;
3149  const BlockDecl::Capture *Capture;
3150};
3151bool operator<(const BlockLayoutChunk &l, const BlockLayoutChunk &r) {
3152  return l.OffsetInBits < r.OffsetInBits;
3153}
3154}
3155
3156void CGDebugInfo::EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
3157                                                       llvm::Value *Arg,
3158                                                       unsigned ArgNo,
3159                                                       llvm::Value *LocalAddr,
3160                                                       CGBuilderTy &Builder) {
3161  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3162  ASTContext &C = CGM.getContext();
3163  const BlockDecl *blockDecl = block.getBlockDecl();
3164
3165  // Collect some general information about the block's location.
3166  SourceLocation loc = blockDecl->getCaretLocation();
3167  llvm::DIFile *tunit = getOrCreateFile(loc);
3168  unsigned line = getLineNumber(loc);
3169  unsigned column = getColumnNumber(loc);
3170
3171  // Build the debug-info type for the block literal.
3172  getDeclContextDescriptor(blockDecl);
3173
3174  const llvm::StructLayout *blockLayout =
3175      CGM.getDataLayout().getStructLayout(block.StructureType);
3176
3177  SmallVector<llvm::Metadata *, 16> fields;
3178  fields.push_back(createFieldType("__isa", C.VoidPtrTy, 0, loc, AS_public,
3179                                   blockLayout->getElementOffsetInBits(0),
3180                                   tunit, tunit));
3181  fields.push_back(createFieldType("__flags", C.IntTy, 0, loc, AS_public,
3182                                   blockLayout->getElementOffsetInBits(1),
3183                                   tunit, tunit));
3184  fields.push_back(createFieldType("__reserved", C.IntTy, 0, loc, AS_public,
3185                                   blockLayout->getElementOffsetInBits(2),
3186                                   tunit, tunit));
3187  auto *FnTy = block.getBlockExpr()->getFunctionType();
3188  auto FnPtrType = CGM.getContext().getPointerType(FnTy->desugar());
3189  fields.push_back(createFieldType("__FuncPtr", FnPtrType, 0, loc, AS_public,
3190                                   blockLayout->getElementOffsetInBits(3),
3191                                   tunit, tunit));
3192  fields.push_back(createFieldType(
3193      "__descriptor", C.getPointerType(block.NeedsCopyDispose
3194                                           ? C.getBlockDescriptorExtendedType()
3195                                           : C.getBlockDescriptorType()),
3196      0, loc, AS_public, blockLayout->getElementOffsetInBits(4), tunit, tunit));
3197
3198  // We want to sort the captures by offset, not because DWARF
3199  // requires this, but because we're paranoid about debuggers.
3200  SmallVector<BlockLayoutChunk, 8> chunks;
3201
3202  // 'this' capture.
3203  if (blockDecl->capturesCXXThis()) {
3204    BlockLayoutChunk chunk;
3205    chunk.OffsetInBits =
3206        blockLayout->getElementOffsetInBits(block.CXXThisIndex);
3207    chunk.Capture = nullptr;
3208    chunks.push_back(chunk);
3209  }
3210
3211  // Variable captures.
3212  for (const auto &capture : blockDecl->captures()) {
3213    const VarDecl *variable = capture.getVariable();
3214    const CGBlockInfo::Capture &captureInfo = block.getCapture(variable);
3215
3216    // Ignore constant captures.
3217    if (captureInfo.isConstant())
3218      continue;
3219
3220    BlockLayoutChunk chunk;
3221    chunk.OffsetInBits =
3222        blockLayout->getElementOffsetInBits(captureInfo.getIndex());
3223    chunk.Capture = &capture;
3224    chunks.push_back(chunk);
3225  }
3226
3227  // Sort by offset.
3228  llvm::array_pod_sort(chunks.begin(), chunks.end());
3229
3230  for (SmallVectorImpl<BlockLayoutChunk>::iterator i = chunks.begin(),
3231                                                   e = chunks.end();
3232       i != e; ++i) {
3233    uint64_t offsetInBits = i->OffsetInBits;
3234    const BlockDecl::Capture *capture = i->Capture;
3235
3236    // If we have a null capture, this must be the C++ 'this' capture.
3237    if (!capture) {
3238      const CXXMethodDecl *method =
3239          cast<CXXMethodDecl>(blockDecl->getNonClosureContext());
3240      QualType type = method->getThisType(C);
3241
3242      fields.push_back(createFieldType("this", type, 0, loc, AS_public,
3243                                       offsetInBits, tunit, tunit));
3244      continue;
3245    }
3246
3247    const VarDecl *variable = capture->getVariable();
3248    StringRef name = variable->getName();
3249
3250    llvm::DIType *fieldType;
3251    if (capture->isByRef()) {
3252      TypeInfo PtrInfo = C.getTypeInfo(C.VoidPtrTy);
3253
3254      // FIXME: this creates a second copy of this type!
3255      uint64_t xoffset;
3256      fieldType = EmitTypeForVarWithBlocksAttr(variable, &xoffset);
3257      fieldType = DBuilder.createPointerType(fieldType, PtrInfo.Width);
3258      fieldType =
3259          DBuilder.createMemberType(tunit, name, tunit, line, PtrInfo.Width,
3260                                    PtrInfo.Align, offsetInBits, 0, fieldType);
3261    } else {
3262      fieldType = createFieldType(name, variable->getType(), 0, loc, AS_public,
3263                                  offsetInBits, tunit, tunit);
3264    }
3265    fields.push_back(fieldType);
3266  }
3267
3268  SmallString<36> typeName;
3269  llvm::raw_svector_ostream(typeName) << "__block_literal_"
3270                                      << CGM.getUniqueBlockCount();
3271
3272  llvm::DINodeArray fieldsArray = DBuilder.getOrCreateArray(fields);
3273
3274  llvm::DIType *type = DBuilder.createStructType(
3275      tunit, typeName.str(), tunit, line,
3276      CGM.getContext().toBits(block.BlockSize),
3277      CGM.getContext().toBits(block.BlockAlign), 0, nullptr, fieldsArray);
3278  type = DBuilder.createPointerType(type, CGM.PointerWidthInBits);
3279
3280  // Get overall information about the block.
3281  unsigned flags = llvm::DINode::FlagArtificial;
3282  auto *scope = cast<llvm::DILocalScope>(LexicalBlockStack.back());
3283
3284  // Create the descriptor for the parameter.
3285  auto *debugVar = DBuilder.createParameterVariable(
3286      scope, Arg->getName(), ArgNo, tunit, line, type,
3287      CGM.getLangOpts().Optimize, flags);
3288
3289  if (LocalAddr) {
3290    // Insert an llvm.dbg.value into the current block.
3291    DBuilder.insertDbgValueIntrinsic(
3292        LocalAddr, 0, debugVar, DBuilder.createExpression(),
3293        llvm::DebugLoc::get(line, column, scope), Builder.GetInsertBlock());
3294  }
3295
3296  // Insert an llvm.dbg.declare into the current block.
3297  DBuilder.insertDeclare(Arg, debugVar, DBuilder.createExpression(),
3298                         llvm::DebugLoc::get(line, column, scope),
3299                         Builder.GetInsertBlock());
3300}
3301
3302llvm::DIDerivedType *
3303CGDebugInfo::getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D) {
3304  if (!D->isStaticDataMember())
3305    return nullptr;
3306
3307  auto MI = StaticDataMemberCache.find(D->getCanonicalDecl());
3308  if (MI != StaticDataMemberCache.end()) {
3309    assert(MI->second && "Static data member declaration should still exist");
3310    return MI->second;
3311  }
3312
3313  // If the member wasn't found in the cache, lazily construct and add it to the
3314  // type (used when a limited form of the type is emitted).
3315  auto DC = D->getDeclContext();
3316  auto *Ctxt = cast<llvm::DICompositeType>(getDeclContextDescriptor(D));
3317  return CreateRecordStaticField(D, Ctxt, cast<RecordDecl>(DC));
3318}
3319
3320llvm::DIGlobalVariable *CGDebugInfo::CollectAnonRecordDecls(
3321    const RecordDecl *RD, llvm::DIFile *Unit, unsigned LineNo,
3322    StringRef LinkageName, llvm::GlobalVariable *Var, llvm::DIScope *DContext) {
3323  llvm::DIGlobalVariable *GV = nullptr;
3324
3325  for (const auto *Field : RD->fields()) {
3326    llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
3327    StringRef FieldName = Field->getName();
3328
3329    // Ignore unnamed fields, but recurse into anonymous records.
3330    if (FieldName.empty()) {
3331      const RecordType *RT = dyn_cast<RecordType>(Field->getType());
3332      if (RT)
3333        GV = CollectAnonRecordDecls(RT->getDecl(), Unit, LineNo, LinkageName,
3334                                    Var, DContext);
3335      continue;
3336    }
3337    // Use VarDecl's Tag, Scope and Line number.
3338    GV = DBuilder.createGlobalVariable(DContext, FieldName, LinkageName, Unit,
3339                                       LineNo, FieldTy,
3340                                       Var->hasInternalLinkage(), Var, nullptr);
3341  }
3342  return GV;
3343}
3344
3345void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
3346                                     const VarDecl *D) {
3347  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3348  // Create global variable debug descriptor.
3349  llvm::DIFile *Unit = nullptr;
3350  llvm::DIScope *DContext = nullptr;
3351  unsigned LineNo;
3352  StringRef DeclName, LinkageName;
3353  QualType T;
3354  collectVarDeclProps(D, Unit, LineNo, T, DeclName, LinkageName, DContext);
3355
3356  // Attempt to store one global variable for the declaration - even if we
3357  // emit a lot of fields.
3358  llvm::DIGlobalVariable *GV = nullptr;
3359
3360  // If this is an anonymous union then we'll want to emit a global
3361  // variable for each member of the anonymous union so that it's possible
3362  // to find the name of any field in the union.
3363  if (T->isUnionType() && DeclName.empty()) {
3364    const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
3365    assert(RD->isAnonymousStructOrUnion() &&
3366           "unnamed non-anonymous struct or union?");
3367    GV = CollectAnonRecordDecls(RD, Unit, LineNo, LinkageName, Var, DContext);
3368  } else {
3369    GV = DBuilder.createGlobalVariable(
3370        DContext, DeclName, LinkageName, Unit, LineNo, getOrCreateType(T, Unit),
3371        Var->hasInternalLinkage(), Var,
3372        getOrCreateStaticDataMemberDeclarationOrNull(D));
3373  }
3374  DeclCache[D->getCanonicalDecl()].reset(static_cast<llvm::Metadata *>(GV));
3375}
3376
3377void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD,
3378                                     llvm::Constant *Init) {
3379  assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
3380  // Create the descriptor for the variable.
3381  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
3382  StringRef Name = VD->getName();
3383  llvm::DIType *Ty = getOrCreateType(VD->getType(), Unit);
3384  if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(VD)) {
3385    const EnumDecl *ED = cast<EnumDecl>(ECD->getDeclContext());
3386    assert(isa<EnumType>(ED->getTypeForDecl()) && "Enum without EnumType?");
3387    Ty = getOrCreateType(QualType(ED->getTypeForDecl(), 0), Unit);
3388  }
3389  // Do not use global variables for enums.
3390  //
3391  // FIXME: why not?
3392  if (Ty->getTag() == llvm::dwarf::DW_TAG_enumeration_type)
3393    return;
3394  // Do not emit separate definitions for function local const/statics.
3395  if (isa<FunctionDecl>(VD->getDeclContext()))
3396    return;
3397  VD = cast<ValueDecl>(VD->getCanonicalDecl());
3398  auto *VarD = cast<VarDecl>(VD);
3399  if (VarD->isStaticDataMember()) {
3400    auto *RD = cast<RecordDecl>(VarD->getDeclContext());
3401    getDeclContextDescriptor(VarD);
3402    // Ensure that the type is retained even though it's otherwise unreferenced.
3403    RetainedTypes.push_back(
3404        CGM.getContext().getRecordType(RD).getAsOpaquePtr());
3405    return;
3406  }
3407
3408  llvm::DIScope *DContext = getDeclContextDescriptor(VD);
3409
3410  auto &GV = DeclCache[VD];
3411  if (GV)
3412    return;
3413  GV.reset(DBuilder.createGlobalVariable(
3414      DContext, Name, StringRef(), Unit, getLineNumber(VD->getLocation()), Ty,
3415      true, Init, getOrCreateStaticDataMemberDeclarationOrNull(VarD)));
3416}
3417
3418llvm::DIScope *CGDebugInfo::getCurrentContextDescriptor(const Decl *D) {
3419  if (!LexicalBlockStack.empty())
3420    return LexicalBlockStack.back();
3421  llvm::DIScope *Mod = getParentModuleOrNull(D);
3422  return getContextDescriptor(D, Mod ? Mod : TheCU);
3423}
3424
3425void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
3426  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
3427    return;
3428  const NamespaceDecl *NSDecl = UD.getNominatedNamespace();
3429  if (!NSDecl->isAnonymousNamespace() ||
3430      CGM.getCodeGenOpts().DebugExplicitImport) {
3431    DBuilder.createImportedModule(
3432        getCurrentContextDescriptor(cast<Decl>(UD.getDeclContext())),
3433        getOrCreateNameSpace(NSDecl),
3434        getLineNumber(UD.getLocation()));
3435  }
3436}
3437
3438void CGDebugInfo::EmitUsingDecl(const UsingDecl &UD) {
3439  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
3440    return;
3441  assert(UD.shadow_size() &&
3442         "We shouldn't be codegening an invalid UsingDecl containing no decls");
3443  // Emitting one decl is sufficient - debuggers can detect that this is an
3444  // overloaded name & provide lookup for all the overloads.
3445  const UsingShadowDecl &USD = **UD.shadow_begin();
3446  if (llvm::DINode *Target =
3447          getDeclarationOrDefinition(USD.getUnderlyingDecl()))
3448    DBuilder.createImportedDeclaration(
3449        getCurrentContextDescriptor(cast<Decl>(USD.getDeclContext())), Target,
3450        getLineNumber(USD.getLocation()));
3451}
3452
3453void CGDebugInfo::EmitImportDecl(const ImportDecl &ID) {
3454  if (Module *M = ID.getImportedModule()) {
3455    auto Info = ExternalASTSource::ASTSourceDescriptor(*M);
3456    DBuilder.createImportedDeclaration(
3457        getCurrentContextDescriptor(cast<Decl>(ID.getDeclContext())),
3458        getOrCreateModuleRef(Info, DebugTypeExtRefs),
3459        getLineNumber(ID.getLocation()));
3460  }
3461}
3462
3463llvm::DIImportedEntity *
3464CGDebugInfo::EmitNamespaceAlias(const NamespaceAliasDecl &NA) {
3465  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
3466    return nullptr;
3467  auto &VH = NamespaceAliasCache[&NA];
3468  if (VH)
3469    return cast<llvm::DIImportedEntity>(VH);
3470  llvm::DIImportedEntity *R;
3471  if (const NamespaceAliasDecl *Underlying =
3472          dyn_cast<NamespaceAliasDecl>(NA.getAliasedNamespace()))
3473    // This could cache & dedup here rather than relying on metadata deduping.
3474    R = DBuilder.createImportedDeclaration(
3475        getCurrentContextDescriptor(cast<Decl>(NA.getDeclContext())),
3476        EmitNamespaceAlias(*Underlying), getLineNumber(NA.getLocation()),
3477        NA.getName());
3478  else
3479    R = DBuilder.createImportedDeclaration(
3480        getCurrentContextDescriptor(cast<Decl>(NA.getDeclContext())),
3481        getOrCreateNameSpace(cast<NamespaceDecl>(NA.getAliasedNamespace())),
3482        getLineNumber(NA.getLocation()), NA.getName());
3483  VH.reset(R);
3484  return R;
3485}
3486
3487llvm::DINamespace *
3488CGDebugInfo::getOrCreateNameSpace(const NamespaceDecl *NSDecl) {
3489  NSDecl = NSDecl->getCanonicalDecl();
3490  auto I = NameSpaceCache.find(NSDecl);
3491  if (I != NameSpaceCache.end())
3492    return cast<llvm::DINamespace>(I->second);
3493
3494  unsigned LineNo = getLineNumber(NSDecl->getLocation());
3495  llvm::DIFile *FileD = getOrCreateFile(NSDecl->getLocation());
3496  llvm::DIScope *Context = getDeclContextDescriptor(NSDecl);
3497  llvm::DINamespace *NS =
3498      DBuilder.createNameSpace(Context, NSDecl->getName(), FileD, LineNo);
3499  NameSpaceCache[NSDecl].reset(NS);
3500  return NS;
3501}
3502
3503void CGDebugInfo::setDwoId(uint64_t Signature) {
3504  assert(TheCU && "no main compile unit");
3505  TheCU->setDWOId(Signature);
3506}
3507
3508
3509void CGDebugInfo::finalize() {
3510  // Creating types might create further types - invalidating the current
3511  // element and the size(), so don't cache/reference them.
3512  for (size_t i = 0; i != ObjCInterfaceCache.size(); ++i) {
3513    ObjCInterfaceCacheEntry E = ObjCInterfaceCache[i];
3514    llvm::DIType *Ty = E.Type->getDecl()->getDefinition()
3515                           ? CreateTypeDefinition(E.Type, E.Unit)
3516                           : E.Decl;
3517    DBuilder.replaceTemporary(llvm::TempDIType(E.Decl), Ty);
3518  }
3519
3520  for (auto p : ReplaceMap) {
3521    assert(p.second);
3522    auto *Ty = cast<llvm::DIType>(p.second);
3523    assert(Ty->isForwardDecl());
3524
3525    auto it = TypeCache.find(p.first);
3526    assert(it != TypeCache.end());
3527    assert(it->second);
3528
3529    DBuilder.replaceTemporary(llvm::TempDIType(Ty),
3530                              cast<llvm::DIType>(it->second));
3531  }
3532
3533  for (const auto &p : FwdDeclReplaceMap) {
3534    assert(p.second);
3535    llvm::TempMDNode FwdDecl(cast<llvm::MDNode>(p.second));
3536    llvm::Metadata *Repl;
3537
3538    auto it = DeclCache.find(p.first);
3539    // If there has been no definition for the declaration, call RAUW
3540    // with ourselves, that will destroy the temporary MDNode and
3541    // replace it with a standard one, avoiding leaking memory.
3542    if (it == DeclCache.end())
3543      Repl = p.second;
3544    else
3545      Repl = it->second;
3546
3547    DBuilder.replaceTemporary(std::move(FwdDecl), cast<llvm::MDNode>(Repl));
3548  }
3549
3550  // We keep our own list of retained types, because we need to look
3551  // up the final type in the type cache.
3552  for (auto &RT : RetainedTypes)
3553    if (auto MD = TypeCache[RT])
3554      DBuilder.retainType(cast<llvm::DIType>(MD));
3555
3556  DBuilder.finalize();
3557}
3558
3559void CGDebugInfo::EmitExplicitCastType(QualType Ty) {
3560  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
3561    return;
3562
3563  if (auto *DieTy = getOrCreateType(Ty, getOrCreateMainFile()))
3564    // Don't ignore in case of explicit cast where it is referenced indirectly.
3565    DBuilder.retainType(DieTy);
3566}
3567