1//===--- CGDebugInfo.cpp - Emit Debug Information for a Module ------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This coordinates the debug information generation while generating code.
10//
11//===----------------------------------------------------------------------===//
12
13#include "CGDebugInfo.h"
14#include "CGBlocks.h"
15#include "CGCXXABI.h"
16#include "CGObjCRuntime.h"
17#include "CGRecordLayout.h"
18#include "CodeGenFunction.h"
19#include "CodeGenModule.h"
20#include "ConstantEmitter.h"
21#include "clang/AST/ASTContext.h"
22#include "clang/AST/Attr.h"
23#include "clang/AST/DeclFriend.h"
24#include "clang/AST/DeclObjC.h"
25#include "clang/AST/DeclTemplate.h"
26#include "clang/AST/Expr.h"
27#include "clang/AST/RecordLayout.h"
28#include "clang/Basic/CodeGenOptions.h"
29#include "clang/Basic/FileManager.h"
30#include "clang/Basic/SourceManager.h"
31#include "clang/Basic/Version.h"
32#include "clang/Frontend/FrontendOptions.h"
33#include "clang/Lex/HeaderSearchOptions.h"
34#include "clang/Lex/ModuleMap.h"
35#include "clang/Lex/PreprocessorOptions.h"
36#include "llvm/ADT/DenseSet.h"
37#include "llvm/ADT/SmallVector.h"
38#include "llvm/ADT/StringExtras.h"
39#include "llvm/IR/Constants.h"
40#include "llvm/IR/DataLayout.h"
41#include "llvm/IR/DerivedTypes.h"
42#include "llvm/IR/Instructions.h"
43#include "llvm/IR/Intrinsics.h"
44#include "llvm/IR/Metadata.h"
45#include "llvm/IR/Module.h"
46#include "llvm/Support/FileSystem.h"
47#include "llvm/Support/MD5.h"
48#include "llvm/Support/Path.h"
49#include "llvm/Support/TimeProfiler.h"
50using namespace clang;
51using namespace clang::CodeGen;
52
53static uint32_t getTypeAlignIfRequired(const Type *Ty, const ASTContext &Ctx) {
54  auto TI = Ctx.getTypeInfo(Ty);
55  return TI.AlignIsRequired ? TI.Align : 0;
56}
57
58static uint32_t getTypeAlignIfRequired(QualType Ty, const ASTContext &Ctx) {
59  return getTypeAlignIfRequired(Ty.getTypePtr(), Ctx);
60}
61
62static uint32_t getDeclAlignIfRequired(const Decl *D, const ASTContext &Ctx) {
63  return D->hasAttr<AlignedAttr>() ? D->getMaxAlignment() : 0;
64}
65
66CGDebugInfo::CGDebugInfo(CodeGenModule &CGM)
67    : CGM(CGM), DebugKind(CGM.getCodeGenOpts().getDebugInfo()),
68      DebugTypeExtRefs(CGM.getCodeGenOpts().DebugTypeExtRefs),
69      DBuilder(CGM.getModule()) {
70  for (const auto &KV : CGM.getCodeGenOpts().DebugPrefixMap)
71    DebugPrefixMap[KV.first] = KV.second;
72  CreateCompileUnit();
73}
74
75CGDebugInfo::~CGDebugInfo() {
76  assert(LexicalBlockStack.empty() &&
77         "Region stack mismatch, stack not empty!");
78}
79
80ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
81                                       SourceLocation TemporaryLocation)
82    : CGF(&CGF) {
83  init(TemporaryLocation);
84}
85
86ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
87                                       bool DefaultToEmpty,
88                                       SourceLocation TemporaryLocation)
89    : CGF(&CGF) {
90  init(TemporaryLocation, DefaultToEmpty);
91}
92
93void ApplyDebugLocation::init(SourceLocation TemporaryLocation,
94                              bool DefaultToEmpty) {
95  auto *DI = CGF->getDebugInfo();
96  if (!DI) {
97    CGF = nullptr;
98    return;
99  }
100
101  OriginalLocation = CGF->Builder.getCurrentDebugLocation();
102
103  if (OriginalLocation && !DI->CGM.getExpressionLocationsEnabled())
104    return;
105
106  if (TemporaryLocation.isValid()) {
107    DI->EmitLocation(CGF->Builder, TemporaryLocation);
108    return;
109  }
110
111  if (DefaultToEmpty) {
112    CGF->Builder.SetCurrentDebugLocation(llvm::DebugLoc());
113    return;
114  }
115
116  // Construct a location that has a valid scope, but no line info.
117  assert(!DI->LexicalBlockStack.empty());
118  CGF->Builder.SetCurrentDebugLocation(
119      llvm::DILocation::get(DI->LexicalBlockStack.back()->getContext(), 0, 0,
120                            DI->LexicalBlockStack.back(), DI->getInlinedAt()));
121}
122
123ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E)
124    : CGF(&CGF) {
125  init(E->getExprLoc());
126}
127
128ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc)
129    : CGF(&CGF) {
130  if (!CGF.getDebugInfo()) {
131    this->CGF = nullptr;
132    return;
133  }
134  OriginalLocation = CGF.Builder.getCurrentDebugLocation();
135  if (Loc)
136    CGF.Builder.SetCurrentDebugLocation(std::move(Loc));
137}
138
139ApplyDebugLocation::~ApplyDebugLocation() {
140  // Query CGF so the location isn't overwritten when location updates are
141  // temporarily disabled (for C++ default function arguments)
142  if (CGF)
143    CGF->Builder.SetCurrentDebugLocation(std::move(OriginalLocation));
144}
145
146ApplyInlineDebugLocation::ApplyInlineDebugLocation(CodeGenFunction &CGF,
147                                                   GlobalDecl InlinedFn)
148    : CGF(&CGF) {
149  if (!CGF.getDebugInfo()) {
150    this->CGF = nullptr;
151    return;
152  }
153  auto &DI = *CGF.getDebugInfo();
154  SavedLocation = DI.getLocation();
155  assert((DI.getInlinedAt() ==
156          CGF.Builder.getCurrentDebugLocation()->getInlinedAt()) &&
157         "CGDebugInfo and IRBuilder are out of sync");
158
159  DI.EmitInlineFunctionStart(CGF.Builder, InlinedFn);
160}
161
162ApplyInlineDebugLocation::~ApplyInlineDebugLocation() {
163  if (!CGF)
164    return;
165  auto &DI = *CGF->getDebugInfo();
166  DI.EmitInlineFunctionEnd(CGF->Builder);
167  DI.EmitLocation(CGF->Builder, SavedLocation);
168}
169
170void CGDebugInfo::setLocation(SourceLocation Loc) {
171  // If the new location isn't valid return.
172  if (Loc.isInvalid())
173    return;
174
175  CurLoc = CGM.getContext().getSourceManager().getExpansionLoc(Loc);
176
177  // If we've changed files in the middle of a lexical scope go ahead
178  // and create a new lexical scope with file node if it's different
179  // from the one in the scope.
180  if (LexicalBlockStack.empty())
181    return;
182
183  SourceManager &SM = CGM.getContext().getSourceManager();
184  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
185  PresumedLoc PCLoc = SM.getPresumedLoc(CurLoc);
186  if (PCLoc.isInvalid() || Scope->getFile() == getOrCreateFile(CurLoc))
187    return;
188
189  if (auto *LBF = dyn_cast<llvm::DILexicalBlockFile>(Scope)) {
190    LexicalBlockStack.pop_back();
191    LexicalBlockStack.emplace_back(DBuilder.createLexicalBlockFile(
192        LBF->getScope(), getOrCreateFile(CurLoc)));
193  } else if (isa<llvm::DILexicalBlock>(Scope) ||
194             isa<llvm::DISubprogram>(Scope)) {
195    LexicalBlockStack.pop_back();
196    LexicalBlockStack.emplace_back(
197        DBuilder.createLexicalBlockFile(Scope, getOrCreateFile(CurLoc)));
198  }
199}
200
201llvm::DIScope *CGDebugInfo::getDeclContextDescriptor(const Decl *D) {
202  llvm::DIScope *Mod = getParentModuleOrNull(D);
203  return getContextDescriptor(cast<Decl>(D->getDeclContext()),
204                              Mod ? Mod : TheCU);
205}
206
207llvm::DIScope *CGDebugInfo::getContextDescriptor(const Decl *Context,
208                                                 llvm::DIScope *Default) {
209  if (!Context)
210    return Default;
211
212  auto I = RegionMap.find(Context);
213  if (I != RegionMap.end()) {
214    llvm::Metadata *V = I->second;
215    return dyn_cast_or_null<llvm::DIScope>(V);
216  }
217
218  // Check namespace.
219  if (const auto *NSDecl = dyn_cast<NamespaceDecl>(Context))
220    return getOrCreateNamespace(NSDecl);
221
222  if (const auto *RDecl = dyn_cast<RecordDecl>(Context))
223    if (!RDecl->isDependentType())
224      return getOrCreateType(CGM.getContext().getTypeDeclType(RDecl),
225                             TheCU->getFile());
226  return Default;
227}
228
229PrintingPolicy CGDebugInfo::getPrintingPolicy() const {
230  PrintingPolicy PP = CGM.getContext().getPrintingPolicy();
231
232  // If we're emitting codeview, it's important to try to match MSVC's naming so
233  // that visualizers written for MSVC will trigger for our class names. In
234  // particular, we can't have spaces between arguments of standard templates
235  // like basic_string and vector, but we must have spaces between consecutive
236  // angle brackets that close nested template argument lists.
237  if (CGM.getCodeGenOpts().EmitCodeView) {
238    PP.MSVCFormatting = true;
239    PP.SplitTemplateClosers = true;
240  } else {
241    // For DWARF, printing rules are underspecified.
242    // SplitTemplateClosers yields better interop with GCC and GDB (PR46052).
243    PP.SplitTemplateClosers = true;
244  }
245
246  // Apply -fdebug-prefix-map.
247  PP.Callbacks = &PrintCB;
248  return PP;
249}
250
251StringRef CGDebugInfo::getFunctionName(const FunctionDecl *FD) {
252  assert(FD && "Invalid FunctionDecl!");
253  IdentifierInfo *FII = FD->getIdentifier();
254  FunctionTemplateSpecializationInfo *Info =
255      FD->getTemplateSpecializationInfo();
256
257  if (!Info && FII)
258    return FII->getName();
259
260  SmallString<128> NS;
261  llvm::raw_svector_ostream OS(NS);
262  FD->printName(OS);
263
264  // Add any template specialization args.
265  if (Info) {
266    const TemplateArgumentList *TArgs = Info->TemplateArguments;
267    printTemplateArgumentList(OS, TArgs->asArray(), getPrintingPolicy());
268  }
269
270  // Copy this name on the side and use its reference.
271  return internString(OS.str());
272}
273
274StringRef CGDebugInfo::getObjCMethodName(const ObjCMethodDecl *OMD) {
275  SmallString<256> MethodName;
276  llvm::raw_svector_ostream OS(MethodName);
277  OS << (OMD->isInstanceMethod() ? '-' : '+') << '[';
278  const DeclContext *DC = OMD->getDeclContext();
279  if (const auto *OID = dyn_cast<ObjCImplementationDecl>(DC)) {
280    OS << OID->getName();
281  } else if (const auto *OID = dyn_cast<ObjCInterfaceDecl>(DC)) {
282    OS << OID->getName();
283  } else if (const auto *OC = dyn_cast<ObjCCategoryDecl>(DC)) {
284    if (OC->IsClassExtension()) {
285      OS << OC->getClassInterface()->getName();
286    } else {
287      OS << OC->getIdentifier()->getNameStart() << '('
288         << OC->getIdentifier()->getNameStart() << ')';
289    }
290  } else if (const auto *OCD = dyn_cast<ObjCCategoryImplDecl>(DC)) {
291    OS << OCD->getClassInterface()->getName() << '(' << OCD->getName() << ')';
292  }
293  OS << ' ' << OMD->getSelector().getAsString() << ']';
294
295  return internString(OS.str());
296}
297
298StringRef CGDebugInfo::getSelectorName(Selector S) {
299  return internString(S.getAsString());
300}
301
302StringRef CGDebugInfo::getClassName(const RecordDecl *RD) {
303  if (isa<ClassTemplateSpecializationDecl>(RD)) {
304    SmallString<128> Name;
305    llvm::raw_svector_ostream OS(Name);
306    PrintingPolicy PP = getPrintingPolicy();
307    PP.PrintCanonicalTypes = true;
308    PP.SuppressInlineNamespace = false;
309    RD->getNameForDiagnostic(OS, PP,
310                             /*Qualified*/ false);
311
312    // Copy this name on the side and use its reference.
313    return internString(Name);
314  }
315
316  // quick optimization to avoid having to intern strings that are already
317  // stored reliably elsewhere
318  if (const IdentifierInfo *II = RD->getIdentifier())
319    return II->getName();
320
321  // The CodeView printer in LLVM wants to see the names of unnamed types
322  // because they need to have a unique identifier.
323  // These names are used to reconstruct the fully qualified type names.
324  if (CGM.getCodeGenOpts().EmitCodeView) {
325    if (const TypedefNameDecl *D = RD->getTypedefNameForAnonDecl()) {
326      assert(RD->getDeclContext() == D->getDeclContext() &&
327             "Typedef should not be in another decl context!");
328      assert(D->getDeclName().getAsIdentifierInfo() &&
329             "Typedef was not named!");
330      return D->getDeclName().getAsIdentifierInfo()->getName();
331    }
332
333    if (CGM.getLangOpts().CPlusPlus) {
334      StringRef Name;
335
336      ASTContext &Context = CGM.getContext();
337      if (const DeclaratorDecl *DD = Context.getDeclaratorForUnnamedTagDecl(RD))
338        // Anonymous types without a name for linkage purposes have their
339        // declarator mangled in if they have one.
340        Name = DD->getName();
341      else if (const TypedefNameDecl *TND =
342                   Context.getTypedefNameForUnnamedTagDecl(RD))
343        // Anonymous types without a name for linkage purposes have their
344        // associate typedef mangled in if they have one.
345        Name = TND->getName();
346
347      // Give lambdas a display name based on their name mangling.
348      if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
349        if (CXXRD->isLambda())
350          return internString(
351              CGM.getCXXABI().getMangleContext().getLambdaString(CXXRD));
352
353      if (!Name.empty()) {
354        SmallString<256> UnnamedType("<unnamed-type-");
355        UnnamedType += Name;
356        UnnamedType += '>';
357        return internString(UnnamedType);
358      }
359    }
360  }
361
362  return StringRef();
363}
364
365Optional<llvm::DIFile::ChecksumKind>
366CGDebugInfo::computeChecksum(FileID FID, SmallString<32> &Checksum) const {
367  Checksum.clear();
368
369  if (!CGM.getCodeGenOpts().EmitCodeView &&
370      CGM.getCodeGenOpts().DwarfVersion < 5)
371    return None;
372
373  SourceManager &SM = CGM.getContext().getSourceManager();
374  Optional<llvm::MemoryBufferRef> MemBuffer = SM.getBufferOrNone(FID);
375  if (!MemBuffer)
376    return None;
377
378  llvm::MD5 Hash;
379  llvm::MD5::MD5Result Result;
380
381  Hash.update(MemBuffer->getBuffer());
382  Hash.final(Result);
383
384  Hash.stringifyResult(Result, Checksum);
385  return llvm::DIFile::CSK_MD5;
386}
387
388Optional<StringRef> CGDebugInfo::getSource(const SourceManager &SM,
389                                           FileID FID) {
390  if (!CGM.getCodeGenOpts().EmbedSource)
391    return None;
392
393  bool SourceInvalid = false;
394  StringRef Source = SM.getBufferData(FID, &SourceInvalid);
395
396  if (SourceInvalid)
397    return None;
398
399  return Source;
400}
401
402llvm::DIFile *CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
403  SourceManager &SM = CGM.getContext().getSourceManager();
404  StringRef FileName;
405  FileID FID;
406
407  if (Loc.isInvalid()) {
408    // The DIFile used by the CU is distinct from the main source file. Call
409    // createFile() below for canonicalization if the source file was specified
410    // with an absolute path.
411    FileName = TheCU->getFile()->getFilename();
412  } else {
413    PresumedLoc PLoc = SM.getPresumedLoc(Loc);
414    FileName = PLoc.getFilename();
415
416    if (FileName.empty()) {
417      FileName = TheCU->getFile()->getFilename();
418    } else {
419      FileName = PLoc.getFilename();
420    }
421    FID = PLoc.getFileID();
422  }
423
424  // Cache the results.
425  auto It = DIFileCache.find(FileName.data());
426  if (It != DIFileCache.end()) {
427    // Verify that the information still exists.
428    if (llvm::Metadata *V = It->second)
429      return cast<llvm::DIFile>(V);
430  }
431
432  SmallString<32> Checksum;
433
434  Optional<llvm::DIFile::ChecksumKind> CSKind = computeChecksum(FID, Checksum);
435  Optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo;
436  if (CSKind)
437    CSInfo.emplace(*CSKind, Checksum);
438  return createFile(FileName, CSInfo, getSource(SM, SM.getFileID(Loc)));
439}
440
441llvm::DIFile *
442CGDebugInfo::createFile(StringRef FileName,
443                        Optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo,
444                        Optional<StringRef> Source) {
445  StringRef Dir;
446  StringRef File;
447  std::string RemappedFile = remapDIPath(FileName);
448  std::string CurDir = remapDIPath(getCurrentDirname());
449  SmallString<128> DirBuf;
450  SmallString<128> FileBuf;
451  if (llvm::sys::path::is_absolute(RemappedFile)) {
452    // Strip the common prefix (if it is more than just "/") from current
453    // directory and FileName for a more space-efficient encoding.
454    auto FileIt = llvm::sys::path::begin(RemappedFile);
455    auto FileE = llvm::sys::path::end(RemappedFile);
456    auto CurDirIt = llvm::sys::path::begin(CurDir);
457    auto CurDirE = llvm::sys::path::end(CurDir);
458    for (; CurDirIt != CurDirE && *CurDirIt == *FileIt; ++CurDirIt, ++FileIt)
459      llvm::sys::path::append(DirBuf, *CurDirIt);
460    if (std::distance(llvm::sys::path::begin(CurDir), CurDirIt) == 1) {
461      // Don't strip the common prefix if it is only the root "/"
462      // since that would make LLVM diagnostic locations confusing.
463      Dir = {};
464      File = RemappedFile;
465    } else {
466      for (; FileIt != FileE; ++FileIt)
467        llvm::sys::path::append(FileBuf, *FileIt);
468      Dir = DirBuf;
469      File = FileBuf;
470    }
471  } else {
472    Dir = CurDir;
473    File = RemappedFile;
474  }
475  llvm::DIFile *F = DBuilder.createFile(File, Dir, CSInfo, Source);
476  DIFileCache[FileName.data()].reset(F);
477  return F;
478}
479
480std::string CGDebugInfo::remapDIPath(StringRef Path) const {
481  if (DebugPrefixMap.empty())
482    return Path.str();
483
484  SmallString<256> P = Path;
485  for (const auto &Entry : DebugPrefixMap)
486    if (llvm::sys::path::replace_path_prefix(P, Entry.first, Entry.second))
487      break;
488  return P.str().str();
489}
490
491unsigned CGDebugInfo::getLineNumber(SourceLocation Loc) {
492  if (Loc.isInvalid())
493    return 0;
494  SourceManager &SM = CGM.getContext().getSourceManager();
495  return SM.getPresumedLoc(Loc).getLine();
496}
497
498unsigned CGDebugInfo::getColumnNumber(SourceLocation Loc, bool Force) {
499  // We may not want column information at all.
500  if (!Force && !CGM.getCodeGenOpts().DebugColumnInfo)
501    return 0;
502
503  // If the location is invalid then use the current column.
504  if (Loc.isInvalid() && CurLoc.isInvalid())
505    return 0;
506  SourceManager &SM = CGM.getContext().getSourceManager();
507  PresumedLoc PLoc = SM.getPresumedLoc(Loc.isValid() ? Loc : CurLoc);
508  return PLoc.isValid() ? PLoc.getColumn() : 0;
509}
510
511StringRef CGDebugInfo::getCurrentDirname() {
512  if (!CGM.getCodeGenOpts().DebugCompilationDir.empty())
513    return CGM.getCodeGenOpts().DebugCompilationDir;
514
515  if (!CWDName.empty())
516    return CWDName;
517  SmallString<256> CWD;
518  llvm::sys::fs::current_path(CWD);
519  return CWDName = internString(CWD);
520}
521
522void CGDebugInfo::CreateCompileUnit() {
523  SmallString<32> Checksum;
524  Optional<llvm::DIFile::ChecksumKind> CSKind;
525  Optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo;
526
527  // Should we be asking the SourceManager for the main file name, instead of
528  // accepting it as an argument? This just causes the main file name to
529  // mismatch with source locations and create extra lexical scopes or
530  // mismatched debug info (a CU with a DW_AT_file of "-", because that's what
531  // the driver passed, but functions/other things have DW_AT_file of "<stdin>"
532  // because that's what the SourceManager says)
533
534  // Get absolute path name.
535  SourceManager &SM = CGM.getContext().getSourceManager();
536  std::string MainFileName = CGM.getCodeGenOpts().MainFileName;
537  if (MainFileName.empty())
538    MainFileName = "<stdin>";
539
540  // The main file name provided via the "-main-file-name" option contains just
541  // the file name itself with no path information. This file name may have had
542  // a relative path, so we look into the actual file entry for the main
543  // file to determine the real absolute path for the file.
544  std::string MainFileDir;
545  if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
546    MainFileDir = std::string(MainFile->getDir()->getName());
547    if (!llvm::sys::path::is_absolute(MainFileName)) {
548      llvm::SmallString<1024> MainFileDirSS(MainFileDir);
549      llvm::sys::path::append(MainFileDirSS, MainFileName);
550      MainFileName =
551          std::string(llvm::sys::path::remove_leading_dotslash(MainFileDirSS));
552    }
553    // If the main file name provided is identical to the input file name, and
554    // if the input file is a preprocessed source, use the module name for
555    // debug info. The module name comes from the name specified in the first
556    // linemarker if the input is a preprocessed source.
557    if (MainFile->getName() == MainFileName &&
558        FrontendOptions::getInputKindForExtension(
559            MainFile->getName().rsplit('.').second)
560            .isPreprocessed())
561      MainFileName = CGM.getModule().getName().str();
562
563    CSKind = computeChecksum(SM.getMainFileID(), Checksum);
564  }
565
566  llvm::dwarf::SourceLanguage LangTag;
567  const LangOptions &LO = CGM.getLangOpts();
568  if (LO.CPlusPlus) {
569    if (LO.ObjC)
570      LangTag = llvm::dwarf::DW_LANG_ObjC_plus_plus;
571    else if (LO.CPlusPlus14 && CGM.getCodeGenOpts().DwarfVersion >= 5)
572      LangTag = llvm::dwarf::DW_LANG_C_plus_plus_14;
573    else if (LO.CPlusPlus11 && CGM.getCodeGenOpts().DwarfVersion >= 5)
574      LangTag = llvm::dwarf::DW_LANG_C_plus_plus_11;
575    else
576      LangTag = llvm::dwarf::DW_LANG_C_plus_plus;
577  } else if (LO.ObjC) {
578    LangTag = llvm::dwarf::DW_LANG_ObjC;
579  } else if (LO.RenderScript) {
580    LangTag = llvm::dwarf::DW_LANG_GOOGLE_RenderScript;
581  } else if (LO.C99) {
582    LangTag = llvm::dwarf::DW_LANG_C99;
583  } else {
584    LangTag = llvm::dwarf::DW_LANG_C89;
585  }
586
587  std::string Producer = getClangFullVersion();
588
589  // Figure out which version of the ObjC runtime we have.
590  unsigned RuntimeVers = 0;
591  if (LO.ObjC)
592    RuntimeVers = LO.ObjCRuntime.isNonFragile() ? 2 : 1;
593
594  llvm::DICompileUnit::DebugEmissionKind EmissionKind;
595  switch (DebugKind) {
596  case codegenoptions::NoDebugInfo:
597  case codegenoptions::LocTrackingOnly:
598    EmissionKind = llvm::DICompileUnit::NoDebug;
599    break;
600  case codegenoptions::DebugLineTablesOnly:
601    EmissionKind = llvm::DICompileUnit::LineTablesOnly;
602    break;
603  case codegenoptions::DebugDirectivesOnly:
604    EmissionKind = llvm::DICompileUnit::DebugDirectivesOnly;
605    break;
606  case codegenoptions::DebugInfoConstructor:
607  case codegenoptions::LimitedDebugInfo:
608  case codegenoptions::FullDebugInfo:
609  case codegenoptions::UnusedTypeInfo:
610    EmissionKind = llvm::DICompileUnit::FullDebug;
611    break;
612  }
613
614  uint64_t DwoId = 0;
615  auto &CGOpts = CGM.getCodeGenOpts();
616  // The DIFile used by the CU is distinct from the main source
617  // file. Its directory part specifies what becomes the
618  // DW_AT_comp_dir (the compilation directory), even if the source
619  // file was specified with an absolute path.
620  if (CSKind)
621    CSInfo.emplace(*CSKind, Checksum);
622  llvm::DIFile *CUFile = DBuilder.createFile(
623      remapDIPath(MainFileName), remapDIPath(getCurrentDirname()), CSInfo,
624      getSource(SM, SM.getMainFileID()));
625
626  StringRef Sysroot, SDK;
627  if (CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::LLDB) {
628    Sysroot = CGM.getHeaderSearchOpts().Sysroot;
629    auto B = llvm::sys::path::rbegin(Sysroot);
630    auto E = llvm::sys::path::rend(Sysroot);
631    auto It = std::find_if(B, E, [](auto SDK) { return SDK.endswith(".sdk"); });
632    if (It != E)
633      SDK = *It;
634  }
635
636  // Create new compile unit.
637  TheCU = DBuilder.createCompileUnit(
638      LangTag, CUFile, CGOpts.EmitVersionIdentMetadata ? Producer : "",
639      LO.Optimize || CGOpts.PrepareForLTO || CGOpts.PrepareForThinLTO,
640      CGOpts.DwarfDebugFlags, RuntimeVers, CGOpts.SplitDwarfFile, EmissionKind,
641      DwoId, CGOpts.SplitDwarfInlining, CGOpts.DebugInfoForProfiling,
642      CGM.getTarget().getTriple().isNVPTX()
643          ? llvm::DICompileUnit::DebugNameTableKind::None
644          : static_cast<llvm::DICompileUnit::DebugNameTableKind>(
645                CGOpts.DebugNameTable),
646      CGOpts.DebugRangesBaseAddress, remapDIPath(Sysroot), SDK);
647}
648
649llvm::DIType *CGDebugInfo::CreateType(const BuiltinType *BT) {
650  llvm::dwarf::TypeKind Encoding;
651  StringRef BTName;
652  switch (BT->getKind()) {
653#define BUILTIN_TYPE(Id, SingletonId)
654#define PLACEHOLDER_TYPE(Id, SingletonId) case BuiltinType::Id:
655#include "clang/AST/BuiltinTypes.def"
656  case BuiltinType::Dependent:
657    llvm_unreachable("Unexpected builtin type");
658  case BuiltinType::NullPtr:
659    return DBuilder.createNullPtrType();
660  case BuiltinType::Void:
661    return nullptr;
662  case BuiltinType::ObjCClass:
663    if (!ClassTy)
664      ClassTy =
665          DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
666                                     "objc_class", TheCU, TheCU->getFile(), 0);
667    return ClassTy;
668  case BuiltinType::ObjCId: {
669    // typedef struct objc_class *Class;
670    // typedef struct objc_object {
671    //  Class isa;
672    // } *id;
673
674    if (ObjTy)
675      return ObjTy;
676
677    if (!ClassTy)
678      ClassTy =
679          DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
680                                     "objc_class", TheCU, TheCU->getFile(), 0);
681
682    unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
683
684    auto *ISATy = DBuilder.createPointerType(ClassTy, Size);
685
686    ObjTy = DBuilder.createStructType(TheCU, "objc_object", TheCU->getFile(), 0,
687                                      0, 0, llvm::DINode::FlagZero, nullptr,
688                                      llvm::DINodeArray());
689
690    DBuilder.replaceArrays(
691        ObjTy, DBuilder.getOrCreateArray(&*DBuilder.createMemberType(
692                   ObjTy, "isa", TheCU->getFile(), 0, Size, 0, 0,
693                   llvm::DINode::FlagZero, ISATy)));
694    return ObjTy;
695  }
696  case BuiltinType::ObjCSel: {
697    if (!SelTy)
698      SelTy = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
699                                         "objc_selector", TheCU,
700                                         TheCU->getFile(), 0);
701    return SelTy;
702  }
703
704#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \
705  case BuiltinType::Id:                                                        \
706    return getOrCreateStructPtrType("opencl_" #ImgType "_" #Suffix "_t",       \
707                                    SingletonId);
708#include "clang/Basic/OpenCLImageTypes.def"
709  case BuiltinType::OCLSampler:
710    return getOrCreateStructPtrType("opencl_sampler_t", OCLSamplerDITy);
711  case BuiltinType::OCLEvent:
712    return getOrCreateStructPtrType("opencl_event_t", OCLEventDITy);
713  case BuiltinType::OCLClkEvent:
714    return getOrCreateStructPtrType("opencl_clk_event_t", OCLClkEventDITy);
715  case BuiltinType::OCLQueue:
716    return getOrCreateStructPtrType("opencl_queue_t", OCLQueueDITy);
717  case BuiltinType::OCLReserveID:
718    return getOrCreateStructPtrType("opencl_reserve_id_t", OCLReserveIDDITy);
719#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
720  case BuiltinType::Id: \
721    return getOrCreateStructPtrType("opencl_" #ExtType, Id##Ty);
722#include "clang/Basic/OpenCLExtensionTypes.def"
723
724#define SVE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
725#include "clang/Basic/AArch64SVEACLETypes.def"
726    {
727      ASTContext::BuiltinVectorTypeInfo Info =
728          CGM.getContext().getBuiltinVectorTypeInfo(BT);
729      unsigned NumElemsPerVG = (Info.EC.getKnownMinValue() * Info.NumVectors) / 2;
730
731      // Debuggers can't extract 1bit from a vector, so will display a
732      // bitpattern for svbool_t instead.
733      if (Info.ElementType == CGM.getContext().BoolTy) {
734        NumElemsPerVG /= 8;
735        Info.ElementType = CGM.getContext().UnsignedCharTy;
736      }
737
738      auto *LowerBound =
739          llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
740              llvm::Type::getInt64Ty(CGM.getLLVMContext()), 0));
741      SmallVector<int64_t, 9> Expr(
742          {llvm::dwarf::DW_OP_constu, NumElemsPerVG, llvm::dwarf::DW_OP_bregx,
743           /* AArch64::VG */ 46, 0, llvm::dwarf::DW_OP_mul,
744           llvm::dwarf::DW_OP_constu, 1, llvm::dwarf::DW_OP_minus});
745      auto *UpperBound = DBuilder.createExpression(Expr);
746
747      llvm::Metadata *Subscript = DBuilder.getOrCreateSubrange(
748          /*count*/ nullptr, LowerBound, UpperBound, /*stride*/ nullptr);
749      llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscript);
750      llvm::DIType *ElemTy =
751          getOrCreateType(Info.ElementType, TheCU->getFile());
752      auto Align = getTypeAlignIfRequired(BT, CGM.getContext());
753      return DBuilder.createVectorType(/*Size*/ 0, Align, ElemTy,
754                                       SubscriptArray);
755    }
756  // It doesn't make sense to generate debug info for PowerPC MMA vector types.
757  // So we return a safe type here to avoid generating an error.
758#define PPC_VECTOR_TYPE(Name, Id, size) \
759  case BuiltinType::Id:
760#include "clang/Basic/PPCTypes.def"
761    return CreateType(cast<const BuiltinType>(CGM.getContext().IntTy));
762
763#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
764#include "clang/Basic/RISCVVTypes.def"
765    {
766      ASTContext::BuiltinVectorTypeInfo Info =
767          CGM.getContext().getBuiltinVectorTypeInfo(BT);
768
769      unsigned ElementCount = Info.EC.getKnownMinValue();
770      unsigned SEW = CGM.getContext().getTypeSize(Info.ElementType);
771
772      bool Fractional = false;
773      unsigned LMUL;
774      unsigned FixedSize = ElementCount * SEW;
775      if (Info.ElementType == CGM.getContext().BoolTy) {
776        // Mask type only occupies one vector register.
777        LMUL = 1;
778      } else if (FixedSize < 64) {
779        // In RVV scalable vector types, we encode 64 bits in the fixed part.
780        Fractional = true;
781        LMUL = 64 / FixedSize;
782      } else {
783        LMUL = FixedSize / 64;
784      }
785
786      // Element count = (VLENB / SEW) x LMUL
787      SmallVector<int64_t, 9> Expr(
788          // The DW_OP_bregx operation has two operands: a register which is
789          // specified by an unsigned LEB128 number, followed by a signed LEB128
790          // offset.
791          {llvm::dwarf::DW_OP_bregx, // Read the contents of a register.
792           4096 + 0xC22,             // RISC-V VLENB CSR register.
793           0, // Offset for DW_OP_bregx. It is dummy here.
794           llvm::dwarf::DW_OP_constu,
795           SEW / 8, // SEW is in bits.
796           llvm::dwarf::DW_OP_div, llvm::dwarf::DW_OP_constu, LMUL});
797      if (Fractional)
798        Expr.push_back(llvm::dwarf::DW_OP_div);
799      else
800        Expr.push_back(llvm::dwarf::DW_OP_mul);
801
802      auto *LowerBound =
803          llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
804              llvm::Type::getInt64Ty(CGM.getLLVMContext()), 0));
805      auto *UpperBound = DBuilder.createExpression(Expr);
806      llvm::Metadata *Subscript = DBuilder.getOrCreateSubrange(
807          /*count*/ nullptr, LowerBound, UpperBound, /*stride*/ nullptr);
808      llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscript);
809      llvm::DIType *ElemTy =
810          getOrCreateType(Info.ElementType, TheCU->getFile());
811
812      auto Align = getTypeAlignIfRequired(BT, CGM.getContext());
813      return DBuilder.createVectorType(/*Size=*/0, Align, ElemTy,
814                                       SubscriptArray);
815    }
816  case BuiltinType::UChar:
817  case BuiltinType::Char_U:
818    Encoding = llvm::dwarf::DW_ATE_unsigned_char;
819    break;
820  case BuiltinType::Char_S:
821  case BuiltinType::SChar:
822    Encoding = llvm::dwarf::DW_ATE_signed_char;
823    break;
824  case BuiltinType::Char8:
825  case BuiltinType::Char16:
826  case BuiltinType::Char32:
827    Encoding = llvm::dwarf::DW_ATE_UTF;
828    break;
829  case BuiltinType::UShort:
830  case BuiltinType::UInt:
831  case BuiltinType::UInt128:
832  case BuiltinType::ULong:
833  case BuiltinType::WChar_U:
834  case BuiltinType::ULongLong:
835    Encoding = llvm::dwarf::DW_ATE_unsigned;
836    break;
837  case BuiltinType::Short:
838  case BuiltinType::Int:
839  case BuiltinType::Int128:
840  case BuiltinType::Long:
841  case BuiltinType::WChar_S:
842  case BuiltinType::LongLong:
843    Encoding = llvm::dwarf::DW_ATE_signed;
844    break;
845  case BuiltinType::Bool:
846    Encoding = llvm::dwarf::DW_ATE_boolean;
847    break;
848  case BuiltinType::Half:
849  case BuiltinType::Float:
850  case BuiltinType::LongDouble:
851  case BuiltinType::Float16:
852  case BuiltinType::BFloat16:
853  case BuiltinType::Float128:
854  case BuiltinType::Double:
855    // FIXME: For targets where long double and __float128 have the same size,
856    // they are currently indistinguishable in the debugger without some
857    // special treatment. However, there is currently no consensus on encoding
858    // and this should be updated once a DWARF encoding exists for distinct
859    // floating point types of the same size.
860    Encoding = llvm::dwarf::DW_ATE_float;
861    break;
862  case BuiltinType::ShortAccum:
863  case BuiltinType::Accum:
864  case BuiltinType::LongAccum:
865  case BuiltinType::ShortFract:
866  case BuiltinType::Fract:
867  case BuiltinType::LongFract:
868  case BuiltinType::SatShortFract:
869  case BuiltinType::SatFract:
870  case BuiltinType::SatLongFract:
871  case BuiltinType::SatShortAccum:
872  case BuiltinType::SatAccum:
873  case BuiltinType::SatLongAccum:
874    Encoding = llvm::dwarf::DW_ATE_signed_fixed;
875    break;
876  case BuiltinType::UShortAccum:
877  case BuiltinType::UAccum:
878  case BuiltinType::ULongAccum:
879  case BuiltinType::UShortFract:
880  case BuiltinType::UFract:
881  case BuiltinType::ULongFract:
882  case BuiltinType::SatUShortAccum:
883  case BuiltinType::SatUAccum:
884  case BuiltinType::SatULongAccum:
885  case BuiltinType::SatUShortFract:
886  case BuiltinType::SatUFract:
887  case BuiltinType::SatULongFract:
888    Encoding = llvm::dwarf::DW_ATE_unsigned_fixed;
889    break;
890  }
891
892  switch (BT->getKind()) {
893  case BuiltinType::Long:
894    BTName = "long int";
895    break;
896  case BuiltinType::LongLong:
897    BTName = "long long int";
898    break;
899  case BuiltinType::ULong:
900    BTName = "long unsigned int";
901    break;
902  case BuiltinType::ULongLong:
903    BTName = "long long unsigned int";
904    break;
905  default:
906    BTName = BT->getName(CGM.getLangOpts());
907    break;
908  }
909  // Bit size and offset of the type.
910  uint64_t Size = CGM.getContext().getTypeSize(BT);
911  return DBuilder.createBasicType(BTName, Size, Encoding);
912}
913
914llvm::DIType *CGDebugInfo::CreateType(const AutoType *Ty) {
915  return DBuilder.createUnspecifiedType("auto");
916}
917
918llvm::DIType *CGDebugInfo::CreateType(const ExtIntType *Ty) {
919
920  StringRef Name = Ty->isUnsigned() ? "unsigned _ExtInt" : "_ExtInt";
921  llvm::dwarf::TypeKind Encoding = Ty->isUnsigned()
922                                       ? llvm::dwarf::DW_ATE_unsigned
923                                       : llvm::dwarf::DW_ATE_signed;
924
925  return DBuilder.createBasicType(Name, CGM.getContext().getTypeSize(Ty),
926                                  Encoding);
927}
928
929llvm::DIType *CGDebugInfo::CreateType(const ComplexType *Ty) {
930  // Bit size and offset of the type.
931  llvm::dwarf::TypeKind Encoding = llvm::dwarf::DW_ATE_complex_float;
932  if (Ty->isComplexIntegerType())
933    Encoding = llvm::dwarf::DW_ATE_lo_user;
934
935  uint64_t Size = CGM.getContext().getTypeSize(Ty);
936  return DBuilder.createBasicType("complex", Size, Encoding);
937}
938
939llvm::DIType *CGDebugInfo::CreateQualifiedType(QualType Ty,
940                                               llvm::DIFile *Unit) {
941  QualifierCollector Qc;
942  const Type *T = Qc.strip(Ty);
943
944  // Ignore these qualifiers for now.
945  Qc.removeObjCGCAttr();
946  Qc.removeAddressSpace();
947  Qc.removeObjCLifetime();
948
949  // We will create one Derived type for one qualifier and recurse to handle any
950  // additional ones.
951  llvm::dwarf::Tag Tag;
952  if (Qc.hasConst()) {
953    Tag = llvm::dwarf::DW_TAG_const_type;
954    Qc.removeConst();
955  } else if (Qc.hasVolatile()) {
956    Tag = llvm::dwarf::DW_TAG_volatile_type;
957    Qc.removeVolatile();
958  } else if (Qc.hasRestrict()) {
959    Tag = llvm::dwarf::DW_TAG_restrict_type;
960    Qc.removeRestrict();
961  } else {
962    assert(Qc.empty() && "Unknown type qualifier for debug info");
963    return getOrCreateType(QualType(T, 0), Unit);
964  }
965
966  auto *FromTy = getOrCreateType(Qc.apply(CGM.getContext(), T), Unit);
967
968  // No need to fill in the Name, Line, Size, Alignment, Offset in case of
969  // CVR derived types.
970  return DBuilder.createQualifiedType(Tag, FromTy);
971}
972
973llvm::DIType *CGDebugInfo::CreateType(const ObjCObjectPointerType *Ty,
974                                      llvm::DIFile *Unit) {
975
976  // The frontend treats 'id' as a typedef to an ObjCObjectType,
977  // whereas 'id<protocol>' is treated as an ObjCPointerType. For the
978  // debug info, we want to emit 'id' in both cases.
979  if (Ty->isObjCQualifiedIdType())
980    return getOrCreateType(CGM.getContext().getObjCIdType(), Unit);
981
982  return CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
983                               Ty->getPointeeType(), Unit);
984}
985
986llvm::DIType *CGDebugInfo::CreateType(const PointerType *Ty,
987                                      llvm::DIFile *Unit) {
988  return CreatePointerLikeType(llvm::dwarf::DW_TAG_pointer_type, Ty,
989                               Ty->getPointeeType(), Unit);
990}
991
992/// \return whether a C++ mangling exists for the type defined by TD.
993static bool hasCXXMangling(const TagDecl *TD, llvm::DICompileUnit *TheCU) {
994  switch (TheCU->getSourceLanguage()) {
995  case llvm::dwarf::DW_LANG_C_plus_plus:
996  case llvm::dwarf::DW_LANG_C_plus_plus_11:
997  case llvm::dwarf::DW_LANG_C_plus_plus_14:
998    return true;
999  case llvm::dwarf::DW_LANG_ObjC_plus_plus:
1000    return isa<CXXRecordDecl>(TD) || isa<EnumDecl>(TD);
1001  default:
1002    return false;
1003  }
1004}
1005
1006// Determines if the debug info for this tag declaration needs a type
1007// identifier. The purpose of the unique identifier is to deduplicate type
1008// information for identical types across TUs. Because of the C++ one definition
1009// rule (ODR), it is valid to assume that the type is defined the same way in
1010// every TU and its debug info is equivalent.
1011//
1012// C does not have the ODR, and it is common for codebases to contain multiple
1013// different definitions of a struct with the same name in different TUs.
1014// Therefore, if the type doesn't have a C++ mangling, don't give it an
1015// identifer. Type information in C is smaller and simpler than C++ type
1016// information, so the increase in debug info size is negligible.
1017//
1018// If the type is not externally visible, it should be unique to the current TU,
1019// and should not need an identifier to participate in type deduplication.
1020// However, when emitting CodeView, the format internally uses these
1021// unique type name identifers for references between debug info. For example,
1022// the method of a class in an anonymous namespace uses the identifer to refer
1023// to its parent class. The Microsoft C++ ABI attempts to provide unique names
1024// for such types, so when emitting CodeView, always use identifiers for C++
1025// types. This may create problems when attempting to emit CodeView when the MS
1026// C++ ABI is not in use.
1027static bool needsTypeIdentifier(const TagDecl *TD, CodeGenModule &CGM,
1028                                llvm::DICompileUnit *TheCU) {
1029  // We only add a type identifier for types with C++ name mangling.
1030  if (!hasCXXMangling(TD, TheCU))
1031    return false;
1032
1033  // Externally visible types with C++ mangling need a type identifier.
1034  if (TD->isExternallyVisible())
1035    return true;
1036
1037  // CodeView types with C++ mangling need a type identifier.
1038  if (CGM.getCodeGenOpts().EmitCodeView)
1039    return true;
1040
1041  return false;
1042}
1043
1044// Returns a unique type identifier string if one exists, or an empty string.
1045static SmallString<256> getTypeIdentifier(const TagType *Ty, CodeGenModule &CGM,
1046                                          llvm::DICompileUnit *TheCU) {
1047  SmallString<256> Identifier;
1048  const TagDecl *TD = Ty->getDecl();
1049
1050  if (!needsTypeIdentifier(TD, CGM, TheCU))
1051    return Identifier;
1052  if (const auto *RD = dyn_cast<CXXRecordDecl>(TD))
1053    if (RD->getDefinition())
1054      if (RD->isDynamicClass() &&
1055          CGM.getVTableLinkage(RD) == llvm::GlobalValue::ExternalLinkage)
1056        return Identifier;
1057
1058  // TODO: This is using the RTTI name. Is there a better way to get
1059  // a unique string for a type?
1060  llvm::raw_svector_ostream Out(Identifier);
1061  CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(QualType(Ty, 0), Out);
1062  return Identifier;
1063}
1064
1065/// \return the appropriate DWARF tag for a composite type.
1066static llvm::dwarf::Tag getTagForRecord(const RecordDecl *RD) {
1067  llvm::dwarf::Tag Tag;
1068  if (RD->isStruct() || RD->isInterface())
1069    Tag = llvm::dwarf::DW_TAG_structure_type;
1070  else if (RD->isUnion())
1071    Tag = llvm::dwarf::DW_TAG_union_type;
1072  else {
1073    // FIXME: This could be a struct type giving a default visibility different
1074    // than C++ class type, but needs llvm metadata changes first.
1075    assert(RD->isClass());
1076    Tag = llvm::dwarf::DW_TAG_class_type;
1077  }
1078  return Tag;
1079}
1080
1081llvm::DICompositeType *
1082CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty,
1083                                      llvm::DIScope *Ctx) {
1084  const RecordDecl *RD = Ty->getDecl();
1085  if (llvm::DIType *T = getTypeOrNull(CGM.getContext().getRecordType(RD)))
1086    return cast<llvm::DICompositeType>(T);
1087  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
1088  const unsigned Line =
1089      getLineNumber(RD->getLocation().isValid() ? RD->getLocation() : CurLoc);
1090  StringRef RDName = getClassName(RD);
1091
1092  uint64_t Size = 0;
1093  uint32_t Align = 0;
1094
1095  const RecordDecl *D = RD->getDefinition();
1096  if (D && D->isCompleteDefinition())
1097    Size = CGM.getContext().getTypeSize(Ty);
1098
1099  llvm::DINode::DIFlags Flags = llvm::DINode::FlagFwdDecl;
1100
1101  // Add flag to nontrivial forward declarations. To be consistent with MSVC,
1102  // add the flag if a record has no definition because we don't know whether
1103  // it will be trivial or not.
1104  if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1105    if (!CXXRD->hasDefinition() ||
1106        (CXXRD->hasDefinition() && !CXXRD->isTrivial()))
1107      Flags |= llvm::DINode::FlagNonTrivial;
1108
1109  // Create the type.
1110  SmallString<256> Identifier;
1111  // Don't include a linkage name in line tables only.
1112  if (CGM.getCodeGenOpts().hasReducedDebugInfo())
1113    Identifier = getTypeIdentifier(Ty, CGM, TheCU);
1114  llvm::DICompositeType *RetTy = DBuilder.createReplaceableCompositeType(
1115      getTagForRecord(RD), RDName, Ctx, DefUnit, Line, 0, Size, Align, Flags,
1116      Identifier);
1117  if (CGM.getCodeGenOpts().DebugFwdTemplateParams)
1118    if (auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
1119      DBuilder.replaceArrays(RetTy, llvm::DINodeArray(),
1120                             CollectCXXTemplateParams(TSpecial, DefUnit));
1121  ReplaceMap.emplace_back(
1122      std::piecewise_construct, std::make_tuple(Ty),
1123      std::make_tuple(static_cast<llvm::Metadata *>(RetTy)));
1124  return RetTy;
1125}
1126
1127llvm::DIType *CGDebugInfo::CreatePointerLikeType(llvm::dwarf::Tag Tag,
1128                                                 const Type *Ty,
1129                                                 QualType PointeeTy,
1130                                                 llvm::DIFile *Unit) {
1131  // Bit size, align and offset of the type.
1132  // Size is always the size of a pointer. We can't use getTypeSize here
1133  // because that does not return the correct value for references.
1134  unsigned AddressSpace = CGM.getContext().getTargetAddressSpace(PointeeTy);
1135  uint64_t Size = CGM.getTarget().getPointerWidth(AddressSpace);
1136  auto Align = getTypeAlignIfRequired(Ty, CGM.getContext());
1137  Optional<unsigned> DWARFAddressSpace =
1138      CGM.getTarget().getDWARFAddressSpace(AddressSpace);
1139
1140  if (Tag == llvm::dwarf::DW_TAG_reference_type ||
1141      Tag == llvm::dwarf::DW_TAG_rvalue_reference_type)
1142    return DBuilder.createReferenceType(Tag, getOrCreateType(PointeeTy, Unit),
1143                                        Size, Align, DWARFAddressSpace);
1144  else
1145    return DBuilder.createPointerType(getOrCreateType(PointeeTy, Unit), Size,
1146                                      Align, DWARFAddressSpace);
1147}
1148
1149llvm::DIType *CGDebugInfo::getOrCreateStructPtrType(StringRef Name,
1150                                                    llvm::DIType *&Cache) {
1151  if (Cache)
1152    return Cache;
1153  Cache = DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type, Name,
1154                                     TheCU, TheCU->getFile(), 0);
1155  unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
1156  Cache = DBuilder.createPointerType(Cache, Size);
1157  return Cache;
1158}
1159
1160uint64_t CGDebugInfo::collectDefaultElementTypesForBlockPointer(
1161    const BlockPointerType *Ty, llvm::DIFile *Unit, llvm::DIDerivedType *DescTy,
1162    unsigned LineNo, SmallVectorImpl<llvm::Metadata *> &EltTys) {
1163  QualType FType;
1164
1165  // Advanced by calls to CreateMemberType in increments of FType, then
1166  // returned as the overall size of the default elements.
1167  uint64_t FieldOffset = 0;
1168
1169  // Blocks in OpenCL have unique constraints which make the standard fields
1170  // redundant while requiring size and align fields for enqueue_kernel. See
1171  // initializeForBlockHeader in CGBlocks.cpp
1172  if (CGM.getLangOpts().OpenCL) {
1173    FType = CGM.getContext().IntTy;
1174    EltTys.push_back(CreateMemberType(Unit, FType, "__size", &FieldOffset));
1175    EltTys.push_back(CreateMemberType(Unit, FType, "__align", &FieldOffset));
1176  } else {
1177    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
1178    EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
1179    FType = CGM.getContext().IntTy;
1180    EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
1181    EltTys.push_back(CreateMemberType(Unit, FType, "__reserved", &FieldOffset));
1182    FType = CGM.getContext().getPointerType(Ty->getPointeeType());
1183    EltTys.push_back(CreateMemberType(Unit, FType, "__FuncPtr", &FieldOffset));
1184    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
1185    uint64_t FieldSize = CGM.getContext().getTypeSize(Ty);
1186    uint32_t FieldAlign = CGM.getContext().getTypeAlign(Ty);
1187    EltTys.push_back(DBuilder.createMemberType(
1188        Unit, "__descriptor", nullptr, LineNo, FieldSize, FieldAlign,
1189        FieldOffset, llvm::DINode::FlagZero, DescTy));
1190    FieldOffset += FieldSize;
1191  }
1192
1193  return FieldOffset;
1194}
1195
1196llvm::DIType *CGDebugInfo::CreateType(const BlockPointerType *Ty,
1197                                      llvm::DIFile *Unit) {
1198  SmallVector<llvm::Metadata *, 8> EltTys;
1199  QualType FType;
1200  uint64_t FieldOffset;
1201  llvm::DINodeArray Elements;
1202
1203  FieldOffset = 0;
1204  FType = CGM.getContext().UnsignedLongTy;
1205  EltTys.push_back(CreateMemberType(Unit, FType, "reserved", &FieldOffset));
1206  EltTys.push_back(CreateMemberType(Unit, FType, "Size", &FieldOffset));
1207
1208  Elements = DBuilder.getOrCreateArray(EltTys);
1209  EltTys.clear();
1210
1211  llvm::DINode::DIFlags Flags = llvm::DINode::FlagAppleBlock;
1212
1213  auto *EltTy =
1214      DBuilder.createStructType(Unit, "__block_descriptor", nullptr, 0,
1215                                FieldOffset, 0, Flags, nullptr, Elements);
1216
1217  // Bit size, align and offset of the type.
1218  uint64_t Size = CGM.getContext().getTypeSize(Ty);
1219
1220  auto *DescTy = DBuilder.createPointerType(EltTy, Size);
1221
1222  FieldOffset = collectDefaultElementTypesForBlockPointer(Ty, Unit, DescTy,
1223                                                          0, EltTys);
1224
1225  Elements = DBuilder.getOrCreateArray(EltTys);
1226
1227  // The __block_literal_generic structs are marked with a special
1228  // DW_AT_APPLE_BLOCK attribute and are an implementation detail only
1229  // the debugger needs to know about. To allow type uniquing, emit
1230  // them without a name or a location.
1231  EltTy = DBuilder.createStructType(Unit, "", nullptr, 0, FieldOffset, 0,
1232                                    Flags, nullptr, Elements);
1233
1234  return DBuilder.createPointerType(EltTy, Size);
1235}
1236
1237llvm::DIType *CGDebugInfo::CreateType(const TemplateSpecializationType *Ty,
1238                                      llvm::DIFile *Unit) {
1239  assert(Ty->isTypeAlias());
1240  llvm::DIType *Src = getOrCreateType(Ty->getAliasedType(), Unit);
1241
1242  auto *AliasDecl =
1243      cast<TypeAliasTemplateDecl>(Ty->getTemplateName().getAsTemplateDecl())
1244          ->getTemplatedDecl();
1245
1246  if (AliasDecl->hasAttr<NoDebugAttr>())
1247    return Src;
1248
1249  SmallString<128> NS;
1250  llvm::raw_svector_ostream OS(NS);
1251  Ty->getTemplateName().print(OS, getPrintingPolicy(), /*qualified*/ false);
1252  printTemplateArgumentList(OS, Ty->template_arguments(), getPrintingPolicy());
1253
1254  SourceLocation Loc = AliasDecl->getLocation();
1255  return DBuilder.createTypedef(Src, OS.str(), getOrCreateFile(Loc),
1256                                getLineNumber(Loc),
1257                                getDeclContextDescriptor(AliasDecl));
1258}
1259
1260llvm::DIType *CGDebugInfo::CreateType(const TypedefType *Ty,
1261                                      llvm::DIFile *Unit) {
1262  llvm::DIType *Underlying =
1263      getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
1264
1265  if (Ty->getDecl()->hasAttr<NoDebugAttr>())
1266    return Underlying;
1267
1268  // We don't set size information, but do specify where the typedef was
1269  // declared.
1270  SourceLocation Loc = Ty->getDecl()->getLocation();
1271
1272  uint32_t Align = getDeclAlignIfRequired(Ty->getDecl(), CGM.getContext());
1273  // Typedefs are derived from some other type.
1274  return DBuilder.createTypedef(Underlying, Ty->getDecl()->getName(),
1275                                getOrCreateFile(Loc), getLineNumber(Loc),
1276                                getDeclContextDescriptor(Ty->getDecl()), Align);
1277}
1278
1279static unsigned getDwarfCC(CallingConv CC) {
1280  switch (CC) {
1281  case CC_C:
1282    // Avoid emitting DW_AT_calling_convention if the C convention was used.
1283    return 0;
1284
1285  case CC_X86StdCall:
1286    return llvm::dwarf::DW_CC_BORLAND_stdcall;
1287  case CC_X86FastCall:
1288    return llvm::dwarf::DW_CC_BORLAND_msfastcall;
1289  case CC_X86ThisCall:
1290    return llvm::dwarf::DW_CC_BORLAND_thiscall;
1291  case CC_X86VectorCall:
1292    return llvm::dwarf::DW_CC_LLVM_vectorcall;
1293  case CC_X86Pascal:
1294    return llvm::dwarf::DW_CC_BORLAND_pascal;
1295  case CC_Win64:
1296    return llvm::dwarf::DW_CC_LLVM_Win64;
1297  case CC_X86_64SysV:
1298    return llvm::dwarf::DW_CC_LLVM_X86_64SysV;
1299  case CC_AAPCS:
1300  case CC_AArch64VectorCall:
1301    return llvm::dwarf::DW_CC_LLVM_AAPCS;
1302  case CC_AAPCS_VFP:
1303    return llvm::dwarf::DW_CC_LLVM_AAPCS_VFP;
1304  case CC_IntelOclBicc:
1305    return llvm::dwarf::DW_CC_LLVM_IntelOclBicc;
1306  case CC_SpirFunction:
1307    return llvm::dwarf::DW_CC_LLVM_SpirFunction;
1308  case CC_OpenCLKernel:
1309    return llvm::dwarf::DW_CC_LLVM_OpenCLKernel;
1310  case CC_Swift:
1311    return llvm::dwarf::DW_CC_LLVM_Swift;
1312  case CC_PreserveMost:
1313    return llvm::dwarf::DW_CC_LLVM_PreserveMost;
1314  case CC_PreserveAll:
1315    return llvm::dwarf::DW_CC_LLVM_PreserveAll;
1316  case CC_X86RegCall:
1317    return llvm::dwarf::DW_CC_LLVM_X86RegCall;
1318  }
1319  return 0;
1320}
1321
1322llvm::DIType *CGDebugInfo::CreateType(const FunctionType *Ty,
1323                                      llvm::DIFile *Unit) {
1324  SmallVector<llvm::Metadata *, 16> EltTys;
1325
1326  // Add the result type at least.
1327  EltTys.push_back(getOrCreateType(Ty->getReturnType(), Unit));
1328
1329  // Set up remainder of arguments if there is a prototype.
1330  // otherwise emit it as a variadic function.
1331  if (isa<FunctionNoProtoType>(Ty))
1332    EltTys.push_back(DBuilder.createUnspecifiedParameter());
1333  else if (const auto *FPT = dyn_cast<FunctionProtoType>(Ty)) {
1334    for (const QualType &ParamType : FPT->param_types())
1335      EltTys.push_back(getOrCreateType(ParamType, Unit));
1336    if (FPT->isVariadic())
1337      EltTys.push_back(DBuilder.createUnspecifiedParameter());
1338  }
1339
1340  llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(EltTys);
1341  return DBuilder.createSubroutineType(EltTypeArray, llvm::DINode::FlagZero,
1342                                       getDwarfCC(Ty->getCallConv()));
1343}
1344
1345/// Convert an AccessSpecifier into the corresponding DINode flag.
1346/// As an optimization, return 0 if the access specifier equals the
1347/// default for the containing type.
1348static llvm::DINode::DIFlags getAccessFlag(AccessSpecifier Access,
1349                                           const RecordDecl *RD) {
1350  AccessSpecifier Default = clang::AS_none;
1351  if (RD && RD->isClass())
1352    Default = clang::AS_private;
1353  else if (RD && (RD->isStruct() || RD->isUnion()))
1354    Default = clang::AS_public;
1355
1356  if (Access == Default)
1357    return llvm::DINode::FlagZero;
1358
1359  switch (Access) {
1360  case clang::AS_private:
1361    return llvm::DINode::FlagPrivate;
1362  case clang::AS_protected:
1363    return llvm::DINode::FlagProtected;
1364  case clang::AS_public:
1365    return llvm::DINode::FlagPublic;
1366  case clang::AS_none:
1367    return llvm::DINode::FlagZero;
1368  }
1369  llvm_unreachable("unexpected access enumerator");
1370}
1371
1372llvm::DIType *CGDebugInfo::createBitFieldType(const FieldDecl *BitFieldDecl,
1373                                              llvm::DIScope *RecordTy,
1374                                              const RecordDecl *RD) {
1375  StringRef Name = BitFieldDecl->getName();
1376  QualType Ty = BitFieldDecl->getType();
1377  SourceLocation Loc = BitFieldDecl->getLocation();
1378  llvm::DIFile *VUnit = getOrCreateFile(Loc);
1379  llvm::DIType *DebugType = getOrCreateType(Ty, VUnit);
1380
1381  // Get the location for the field.
1382  llvm::DIFile *File = getOrCreateFile(Loc);
1383  unsigned Line = getLineNumber(Loc);
1384
1385  const CGBitFieldInfo &BitFieldInfo =
1386      CGM.getTypes().getCGRecordLayout(RD).getBitFieldInfo(BitFieldDecl);
1387  uint64_t SizeInBits = BitFieldInfo.Size;
1388  assert(SizeInBits > 0 && "found named 0-width bitfield");
1389  uint64_t StorageOffsetInBits =
1390      CGM.getContext().toBits(BitFieldInfo.StorageOffset);
1391  uint64_t Offset = BitFieldInfo.Offset;
1392  // The bit offsets for big endian machines are reversed for big
1393  // endian target, compensate for that as the DIDerivedType requires
1394  // un-reversed offsets.
1395  if (CGM.getDataLayout().isBigEndian())
1396    Offset = BitFieldInfo.StorageSize - BitFieldInfo.Size - Offset;
1397  uint64_t OffsetInBits = StorageOffsetInBits + Offset;
1398  llvm::DINode::DIFlags Flags = getAccessFlag(BitFieldDecl->getAccess(), RD);
1399  return DBuilder.createBitFieldMemberType(
1400      RecordTy, Name, File, Line, SizeInBits, OffsetInBits, StorageOffsetInBits,
1401      Flags, DebugType);
1402}
1403
1404llvm::DIType *
1405CGDebugInfo::createFieldType(StringRef name, QualType type, SourceLocation loc,
1406                             AccessSpecifier AS, uint64_t offsetInBits,
1407                             uint32_t AlignInBits, llvm::DIFile *tunit,
1408                             llvm::DIScope *scope, const RecordDecl *RD) {
1409  llvm::DIType *debugType = getOrCreateType(type, tunit);
1410
1411  // Get the location for the field.
1412  llvm::DIFile *file = getOrCreateFile(loc);
1413  const unsigned line = getLineNumber(loc.isValid() ? loc : CurLoc);
1414
1415  uint64_t SizeInBits = 0;
1416  auto Align = AlignInBits;
1417  if (!type->isIncompleteArrayType()) {
1418    TypeInfo TI = CGM.getContext().getTypeInfo(type);
1419    SizeInBits = TI.Width;
1420    if (!Align)
1421      Align = getTypeAlignIfRequired(type, CGM.getContext());
1422  }
1423
1424  llvm::DINode::DIFlags flags = getAccessFlag(AS, RD);
1425  return DBuilder.createMemberType(scope, name, file, line, SizeInBits, Align,
1426                                   offsetInBits, flags, debugType);
1427}
1428
1429void CGDebugInfo::CollectRecordLambdaFields(
1430    const CXXRecordDecl *CXXDecl, SmallVectorImpl<llvm::Metadata *> &elements,
1431    llvm::DIType *RecordTy) {
1432  // For C++11 Lambdas a Field will be the same as a Capture, but the Capture
1433  // has the name and the location of the variable so we should iterate over
1434  // both concurrently.
1435  const ASTRecordLayout &layout = CGM.getContext().getASTRecordLayout(CXXDecl);
1436  RecordDecl::field_iterator Field = CXXDecl->field_begin();
1437  unsigned fieldno = 0;
1438  for (CXXRecordDecl::capture_const_iterator I = CXXDecl->captures_begin(),
1439                                             E = CXXDecl->captures_end();
1440       I != E; ++I, ++Field, ++fieldno) {
1441    const LambdaCapture &C = *I;
1442    if (C.capturesVariable()) {
1443      SourceLocation Loc = C.getLocation();
1444      assert(!Field->isBitField() && "lambdas don't have bitfield members!");
1445      VarDecl *V = C.getCapturedVar();
1446      StringRef VName = V->getName();
1447      llvm::DIFile *VUnit = getOrCreateFile(Loc);
1448      auto Align = getDeclAlignIfRequired(V, CGM.getContext());
1449      llvm::DIType *FieldType = createFieldType(
1450          VName, Field->getType(), Loc, Field->getAccess(),
1451          layout.getFieldOffset(fieldno), Align, VUnit, RecordTy, CXXDecl);
1452      elements.push_back(FieldType);
1453    } else if (C.capturesThis()) {
1454      // TODO: Need to handle 'this' in some way by probably renaming the
1455      // this of the lambda class and having a field member of 'this' or
1456      // by using AT_object_pointer for the function and having that be
1457      // used as 'this' for semantic references.
1458      FieldDecl *f = *Field;
1459      llvm::DIFile *VUnit = getOrCreateFile(f->getLocation());
1460      QualType type = f->getType();
1461      llvm::DIType *fieldType = createFieldType(
1462          "this", type, f->getLocation(), f->getAccess(),
1463          layout.getFieldOffset(fieldno), VUnit, RecordTy, CXXDecl);
1464
1465      elements.push_back(fieldType);
1466    }
1467  }
1468}
1469
1470llvm::DIDerivedType *
1471CGDebugInfo::CreateRecordStaticField(const VarDecl *Var, llvm::DIType *RecordTy,
1472                                     const RecordDecl *RD) {
1473  // Create the descriptor for the static variable, with or without
1474  // constant initializers.
1475  Var = Var->getCanonicalDecl();
1476  llvm::DIFile *VUnit = getOrCreateFile(Var->getLocation());
1477  llvm::DIType *VTy = getOrCreateType(Var->getType(), VUnit);
1478
1479  unsigned LineNumber = getLineNumber(Var->getLocation());
1480  StringRef VName = Var->getName();
1481  llvm::Constant *C = nullptr;
1482  if (Var->getInit()) {
1483    const APValue *Value = Var->evaluateValue();
1484    if (Value) {
1485      if (Value->isInt())
1486        C = llvm::ConstantInt::get(CGM.getLLVMContext(), Value->getInt());
1487      if (Value->isFloat())
1488        C = llvm::ConstantFP::get(CGM.getLLVMContext(), Value->getFloat());
1489    }
1490  }
1491
1492  llvm::DINode::DIFlags Flags = getAccessFlag(Var->getAccess(), RD);
1493  auto Align = getDeclAlignIfRequired(Var, CGM.getContext());
1494  llvm::DIDerivedType *GV = DBuilder.createStaticMemberType(
1495      RecordTy, VName, VUnit, LineNumber, VTy, Flags, C, Align);
1496  StaticDataMemberCache[Var->getCanonicalDecl()].reset(GV);
1497  return GV;
1498}
1499
1500void CGDebugInfo::CollectRecordNormalField(
1501    const FieldDecl *field, uint64_t OffsetInBits, llvm::DIFile *tunit,
1502    SmallVectorImpl<llvm::Metadata *> &elements, llvm::DIType *RecordTy,
1503    const RecordDecl *RD) {
1504  StringRef name = field->getName();
1505  QualType type = field->getType();
1506
1507  // Ignore unnamed fields unless they're anonymous structs/unions.
1508  if (name.empty() && !type->isRecordType())
1509    return;
1510
1511  llvm::DIType *FieldType;
1512  if (field->isBitField()) {
1513    FieldType = createBitFieldType(field, RecordTy, RD);
1514  } else {
1515    auto Align = getDeclAlignIfRequired(field, CGM.getContext());
1516    FieldType =
1517        createFieldType(name, type, field->getLocation(), field->getAccess(),
1518                        OffsetInBits, Align, tunit, RecordTy, RD);
1519  }
1520
1521  elements.push_back(FieldType);
1522}
1523
1524void CGDebugInfo::CollectRecordNestedType(
1525    const TypeDecl *TD, SmallVectorImpl<llvm::Metadata *> &elements) {
1526  QualType Ty = CGM.getContext().getTypeDeclType(TD);
1527  // Injected class names are not considered nested records.
1528  if (isa<InjectedClassNameType>(Ty))
1529    return;
1530  SourceLocation Loc = TD->getLocation();
1531  llvm::DIType *nestedType = getOrCreateType(Ty, getOrCreateFile(Loc));
1532  elements.push_back(nestedType);
1533}
1534
1535void CGDebugInfo::CollectRecordFields(
1536    const RecordDecl *record, llvm::DIFile *tunit,
1537    SmallVectorImpl<llvm::Metadata *> &elements,
1538    llvm::DICompositeType *RecordTy) {
1539  const auto *CXXDecl = dyn_cast<CXXRecordDecl>(record);
1540
1541  if (CXXDecl && CXXDecl->isLambda())
1542    CollectRecordLambdaFields(CXXDecl, elements, RecordTy);
1543  else {
1544    const ASTRecordLayout &layout = CGM.getContext().getASTRecordLayout(record);
1545
1546    // Field number for non-static fields.
1547    unsigned fieldNo = 0;
1548
1549    // Static and non-static members should appear in the same order as
1550    // the corresponding declarations in the source program.
1551    for (const auto *I : record->decls())
1552      if (const auto *V = dyn_cast<VarDecl>(I)) {
1553        if (V->hasAttr<NoDebugAttr>())
1554          continue;
1555
1556        // Skip variable template specializations when emitting CodeView. MSVC
1557        // doesn't emit them.
1558        if (CGM.getCodeGenOpts().EmitCodeView &&
1559            isa<VarTemplateSpecializationDecl>(V))
1560          continue;
1561
1562        if (isa<VarTemplatePartialSpecializationDecl>(V))
1563          continue;
1564
1565        // Reuse the existing static member declaration if one exists
1566        auto MI = StaticDataMemberCache.find(V->getCanonicalDecl());
1567        if (MI != StaticDataMemberCache.end()) {
1568          assert(MI->second &&
1569                 "Static data member declaration should still exist");
1570          elements.push_back(MI->second);
1571        } else {
1572          auto Field = CreateRecordStaticField(V, RecordTy, record);
1573          elements.push_back(Field);
1574        }
1575      } else if (const auto *field = dyn_cast<FieldDecl>(I)) {
1576        CollectRecordNormalField(field, layout.getFieldOffset(fieldNo), tunit,
1577                                 elements, RecordTy, record);
1578
1579        // Bump field number for next field.
1580        ++fieldNo;
1581      } else if (CGM.getCodeGenOpts().EmitCodeView) {
1582        // Debug info for nested types is included in the member list only for
1583        // CodeView.
1584        if (const auto *nestedType = dyn_cast<TypeDecl>(I))
1585          if (!nestedType->isImplicit() &&
1586              nestedType->getDeclContext() == record)
1587            CollectRecordNestedType(nestedType, elements);
1588      }
1589  }
1590}
1591
1592llvm::DISubroutineType *
1593CGDebugInfo::getOrCreateMethodType(const CXXMethodDecl *Method,
1594                                   llvm::DIFile *Unit, bool decl) {
1595  const FunctionProtoType *Func = Method->getType()->getAs<FunctionProtoType>();
1596  if (Method->isStatic())
1597    return cast_or_null<llvm::DISubroutineType>(
1598        getOrCreateType(QualType(Func, 0), Unit));
1599  return getOrCreateInstanceMethodType(Method->getThisType(), Func, Unit, decl);
1600}
1601
1602llvm::DISubroutineType *
1603CGDebugInfo::getOrCreateInstanceMethodType(QualType ThisPtr,
1604                                           const FunctionProtoType *Func,
1605                                           llvm::DIFile *Unit, bool decl) {
1606  // Add "this" pointer.
1607  llvm::DITypeRefArray Args(
1608      cast<llvm::DISubroutineType>(getOrCreateType(QualType(Func, 0), Unit))
1609          ->getTypeArray());
1610  assert(Args.size() && "Invalid number of arguments!");
1611
1612  SmallVector<llvm::Metadata *, 16> Elts;
1613  // First element is always return type. For 'void' functions it is NULL.
1614  QualType temp = Func->getReturnType();
1615  if (temp->getTypeClass() == Type::Auto && decl)
1616    Elts.push_back(CreateType(cast<AutoType>(temp)));
1617  else
1618    Elts.push_back(Args[0]);
1619
1620  // "this" pointer is always first argument.
1621  const CXXRecordDecl *RD = ThisPtr->getPointeeCXXRecordDecl();
1622  if (isa<ClassTemplateSpecializationDecl>(RD)) {
1623    // Create pointer type directly in this case.
1624    const PointerType *ThisPtrTy = cast<PointerType>(ThisPtr);
1625    QualType PointeeTy = ThisPtrTy->getPointeeType();
1626    unsigned AS = CGM.getContext().getTargetAddressSpace(PointeeTy);
1627    uint64_t Size = CGM.getTarget().getPointerWidth(AS);
1628    auto Align = getTypeAlignIfRequired(ThisPtrTy, CGM.getContext());
1629    llvm::DIType *PointeeType = getOrCreateType(PointeeTy, Unit);
1630    llvm::DIType *ThisPtrType =
1631        DBuilder.createPointerType(PointeeType, Size, Align);
1632    TypeCache[ThisPtr.getAsOpaquePtr()].reset(ThisPtrType);
1633    // TODO: This and the artificial type below are misleading, the
1634    // types aren't artificial the argument is, but the current
1635    // metadata doesn't represent that.
1636    ThisPtrType = DBuilder.createObjectPointerType(ThisPtrType);
1637    Elts.push_back(ThisPtrType);
1638  } else {
1639    llvm::DIType *ThisPtrType = getOrCreateType(ThisPtr, Unit);
1640    TypeCache[ThisPtr.getAsOpaquePtr()].reset(ThisPtrType);
1641    ThisPtrType = DBuilder.createObjectPointerType(ThisPtrType);
1642    Elts.push_back(ThisPtrType);
1643  }
1644
1645  // Copy rest of the arguments.
1646  for (unsigned i = 1, e = Args.size(); i != e; ++i)
1647    Elts.push_back(Args[i]);
1648
1649  llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(Elts);
1650
1651  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
1652  if (Func->getExtProtoInfo().RefQualifier == RQ_LValue)
1653    Flags |= llvm::DINode::FlagLValueReference;
1654  if (Func->getExtProtoInfo().RefQualifier == RQ_RValue)
1655    Flags |= llvm::DINode::FlagRValueReference;
1656
1657  return DBuilder.createSubroutineType(EltTypeArray, Flags,
1658                                       getDwarfCC(Func->getCallConv()));
1659}
1660
1661/// isFunctionLocalClass - Return true if CXXRecordDecl is defined
1662/// inside a function.
1663static bool isFunctionLocalClass(const CXXRecordDecl *RD) {
1664  if (const auto *NRD = dyn_cast<CXXRecordDecl>(RD->getDeclContext()))
1665    return isFunctionLocalClass(NRD);
1666  if (isa<FunctionDecl>(RD->getDeclContext()))
1667    return true;
1668  return false;
1669}
1670
1671llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
1672    const CXXMethodDecl *Method, llvm::DIFile *Unit, llvm::DIType *RecordTy) {
1673  bool IsCtorOrDtor =
1674      isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method);
1675
1676  StringRef MethodName = getFunctionName(Method);
1677  llvm::DISubroutineType *MethodTy = getOrCreateMethodType(Method, Unit, true);
1678
1679  // Since a single ctor/dtor corresponds to multiple functions, it doesn't
1680  // make sense to give a single ctor/dtor a linkage name.
1681  StringRef MethodLinkageName;
1682  // FIXME: 'isFunctionLocalClass' seems like an arbitrary/unintentional
1683  // property to use here. It may've been intended to model "is non-external
1684  // type" but misses cases of non-function-local but non-external classes such
1685  // as those in anonymous namespaces as well as the reverse - external types
1686  // that are function local, such as those in (non-local) inline functions.
1687  if (!IsCtorOrDtor && !isFunctionLocalClass(Method->getParent()))
1688    MethodLinkageName = CGM.getMangledName(Method);
1689
1690  // Get the location for the method.
1691  llvm::DIFile *MethodDefUnit = nullptr;
1692  unsigned MethodLine = 0;
1693  if (!Method->isImplicit()) {
1694    MethodDefUnit = getOrCreateFile(Method->getLocation());
1695    MethodLine = getLineNumber(Method->getLocation());
1696  }
1697
1698  // Collect virtual method info.
1699  llvm::DIType *ContainingType = nullptr;
1700  unsigned VIndex = 0;
1701  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
1702  llvm::DISubprogram::DISPFlags SPFlags = llvm::DISubprogram::SPFlagZero;
1703  int ThisAdjustment = 0;
1704
1705  if (Method->isVirtual()) {
1706    if (Method->isPure())
1707      SPFlags |= llvm::DISubprogram::SPFlagPureVirtual;
1708    else
1709      SPFlags |= llvm::DISubprogram::SPFlagVirtual;
1710
1711    if (CGM.getTarget().getCXXABI().isItaniumFamily()) {
1712      // It doesn't make sense to give a virtual destructor a vtable index,
1713      // since a single destructor has two entries in the vtable.
1714      if (!isa<CXXDestructorDecl>(Method))
1715        VIndex = CGM.getItaniumVTableContext().getMethodVTableIndex(Method);
1716    } else {
1717      // Emit MS ABI vftable information.  There is only one entry for the
1718      // deleting dtor.
1719      const auto *DD = dyn_cast<CXXDestructorDecl>(Method);
1720      GlobalDecl GD = DD ? GlobalDecl(DD, Dtor_Deleting) : GlobalDecl(Method);
1721      MethodVFTableLocation ML =
1722          CGM.getMicrosoftVTableContext().getMethodVFTableLocation(GD);
1723      VIndex = ML.Index;
1724
1725      // CodeView only records the vftable offset in the class that introduces
1726      // the virtual method. This is possible because, unlike Itanium, the MS
1727      // C++ ABI does not include all virtual methods from non-primary bases in
1728      // the vtable for the most derived class. For example, if C inherits from
1729      // A and B, C's primary vftable will not include B's virtual methods.
1730      if (Method->size_overridden_methods() == 0)
1731        Flags |= llvm::DINode::FlagIntroducedVirtual;
1732
1733      // The 'this' adjustment accounts for both the virtual and non-virtual
1734      // portions of the adjustment. Presumably the debugger only uses it when
1735      // it knows the dynamic type of an object.
1736      ThisAdjustment = CGM.getCXXABI()
1737                           .getVirtualFunctionPrologueThisAdjustment(GD)
1738                           .getQuantity();
1739    }
1740    ContainingType = RecordTy;
1741  }
1742
1743  // We're checking for deleted C++ special member functions
1744  // [Ctors,Dtors, Copy/Move]
1745  auto checkAttrDeleted = [&](const auto *Method) {
1746    if (Method->getCanonicalDecl()->isDeleted())
1747      SPFlags |= llvm::DISubprogram::SPFlagDeleted;
1748  };
1749
1750  switch (Method->getKind()) {
1751
1752  case Decl::CXXConstructor:
1753  case Decl::CXXDestructor:
1754    checkAttrDeleted(Method);
1755    break;
1756  case Decl::CXXMethod:
1757    if (Method->isCopyAssignmentOperator() ||
1758        Method->isMoveAssignmentOperator())
1759      checkAttrDeleted(Method);
1760    break;
1761  default:
1762    break;
1763  }
1764
1765  if (Method->isNoReturn())
1766    Flags |= llvm::DINode::FlagNoReturn;
1767
1768  if (Method->isStatic())
1769    Flags |= llvm::DINode::FlagStaticMember;
1770  if (Method->isImplicit())
1771    Flags |= llvm::DINode::FlagArtificial;
1772  Flags |= getAccessFlag(Method->getAccess(), Method->getParent());
1773  if (const auto *CXXC = dyn_cast<CXXConstructorDecl>(Method)) {
1774    if (CXXC->isExplicit())
1775      Flags |= llvm::DINode::FlagExplicit;
1776  } else if (const auto *CXXC = dyn_cast<CXXConversionDecl>(Method)) {
1777    if (CXXC->isExplicit())
1778      Flags |= llvm::DINode::FlagExplicit;
1779  }
1780  if (Method->hasPrototype())
1781    Flags |= llvm::DINode::FlagPrototyped;
1782  if (Method->getRefQualifier() == RQ_LValue)
1783    Flags |= llvm::DINode::FlagLValueReference;
1784  if (Method->getRefQualifier() == RQ_RValue)
1785    Flags |= llvm::DINode::FlagRValueReference;
1786  if (!Method->isExternallyVisible())
1787    SPFlags |= llvm::DISubprogram::SPFlagLocalToUnit;
1788  if (CGM.getLangOpts().Optimize)
1789    SPFlags |= llvm::DISubprogram::SPFlagOptimized;
1790
1791  // In this debug mode, emit type info for a class when its constructor type
1792  // info is emitted.
1793  if (DebugKind == codegenoptions::DebugInfoConstructor)
1794    if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Method))
1795      completeUnusedClass(*CD->getParent());
1796
1797  llvm::DINodeArray TParamsArray = CollectFunctionTemplateParams(Method, Unit);
1798  llvm::DISubprogram *SP = DBuilder.createMethod(
1799      RecordTy, MethodName, MethodLinkageName, MethodDefUnit, MethodLine,
1800      MethodTy, VIndex, ThisAdjustment, ContainingType, Flags, SPFlags,
1801      TParamsArray.get());
1802
1803  SPCache[Method->getCanonicalDecl()].reset(SP);
1804
1805  return SP;
1806}
1807
1808void CGDebugInfo::CollectCXXMemberFunctions(
1809    const CXXRecordDecl *RD, llvm::DIFile *Unit,
1810    SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy) {
1811
1812  // Since we want more than just the individual member decls if we
1813  // have templated functions iterate over every declaration to gather
1814  // the functions.
1815  for (const auto *I : RD->decls()) {
1816    const auto *Method = dyn_cast<CXXMethodDecl>(I);
1817    // If the member is implicit, don't add it to the member list. This avoids
1818    // the member being added to type units by LLVM, while still allowing it
1819    // to be emitted into the type declaration/reference inside the compile
1820    // unit.
1821    // Ditto 'nodebug' methods, for consistency with CodeGenFunction.cpp.
1822    // FIXME: Handle Using(Shadow?)Decls here to create
1823    // DW_TAG_imported_declarations inside the class for base decls brought into
1824    // derived classes. GDB doesn't seem to notice/leverage these when I tried
1825    // it, so I'm not rushing to fix this. (GCC seems to produce them, if
1826    // referenced)
1827    if (!Method || Method->isImplicit() || Method->hasAttr<NoDebugAttr>())
1828      continue;
1829
1830    if (Method->getType()->castAs<FunctionProtoType>()->getContainedAutoType())
1831      continue;
1832
1833    // Reuse the existing member function declaration if it exists.
1834    // It may be associated with the declaration of the type & should be
1835    // reused as we're building the definition.
1836    //
1837    // This situation can arise in the vtable-based debug info reduction where
1838    // implicit members are emitted in a non-vtable TU.
1839    auto MI = SPCache.find(Method->getCanonicalDecl());
1840    EltTys.push_back(MI == SPCache.end()
1841                         ? CreateCXXMemberFunction(Method, Unit, RecordTy)
1842                         : static_cast<llvm::Metadata *>(MI->second));
1843  }
1844}
1845
1846void CGDebugInfo::CollectCXXBases(const CXXRecordDecl *RD, llvm::DIFile *Unit,
1847                                  SmallVectorImpl<llvm::Metadata *> &EltTys,
1848                                  llvm::DIType *RecordTy) {
1849  llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> SeenTypes;
1850  CollectCXXBasesAux(RD, Unit, EltTys, RecordTy, RD->bases(), SeenTypes,
1851                     llvm::DINode::FlagZero);
1852
1853  // If we are generating CodeView debug info, we also need to emit records for
1854  // indirect virtual base classes.
1855  if (CGM.getCodeGenOpts().EmitCodeView) {
1856    CollectCXXBasesAux(RD, Unit, EltTys, RecordTy, RD->vbases(), SeenTypes,
1857                       llvm::DINode::FlagIndirectVirtualBase);
1858  }
1859}
1860
1861void CGDebugInfo::CollectCXXBasesAux(
1862    const CXXRecordDecl *RD, llvm::DIFile *Unit,
1863    SmallVectorImpl<llvm::Metadata *> &EltTys, llvm::DIType *RecordTy,
1864    const CXXRecordDecl::base_class_const_range &Bases,
1865    llvm::DenseSet<CanonicalDeclPtr<const CXXRecordDecl>> &SeenTypes,
1866    llvm::DINode::DIFlags StartingFlags) {
1867  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
1868  for (const auto &BI : Bases) {
1869    const auto *Base =
1870        cast<CXXRecordDecl>(BI.getType()->castAs<RecordType>()->getDecl());
1871    if (!SeenTypes.insert(Base).second)
1872      continue;
1873    auto *BaseTy = getOrCreateType(BI.getType(), Unit);
1874    llvm::DINode::DIFlags BFlags = StartingFlags;
1875    uint64_t BaseOffset;
1876    uint32_t VBPtrOffset = 0;
1877
1878    if (BI.isVirtual()) {
1879      if (CGM.getTarget().getCXXABI().isItaniumFamily()) {
1880        // virtual base offset offset is -ve. The code generator emits dwarf
1881        // expression where it expects +ve number.
1882        BaseOffset = 0 - CGM.getItaniumVTableContext()
1883                             .getVirtualBaseOffsetOffset(RD, Base)
1884                             .getQuantity();
1885      } else {
1886        // In the MS ABI, store the vbtable offset, which is analogous to the
1887        // vbase offset offset in Itanium.
1888        BaseOffset =
1889            4 * CGM.getMicrosoftVTableContext().getVBTableIndex(RD, Base);
1890        VBPtrOffset = CGM.getContext()
1891                          .getASTRecordLayout(RD)
1892                          .getVBPtrOffset()
1893                          .getQuantity();
1894      }
1895      BFlags |= llvm::DINode::FlagVirtual;
1896    } else
1897      BaseOffset = CGM.getContext().toBits(RL.getBaseClassOffset(Base));
1898    // FIXME: Inconsistent units for BaseOffset. It is in bytes when
1899    // BI->isVirtual() and bits when not.
1900
1901    BFlags |= getAccessFlag(BI.getAccessSpecifier(), RD);
1902    llvm::DIType *DTy = DBuilder.createInheritance(RecordTy, BaseTy, BaseOffset,
1903                                                   VBPtrOffset, BFlags);
1904    EltTys.push_back(DTy);
1905  }
1906}
1907
1908llvm::DINodeArray
1909CGDebugInfo::CollectTemplateParams(const TemplateParameterList *TPList,
1910                                   ArrayRef<TemplateArgument> TAList,
1911                                   llvm::DIFile *Unit) {
1912  SmallVector<llvm::Metadata *, 16> TemplateParams;
1913  for (unsigned i = 0, e = TAList.size(); i != e; ++i) {
1914    const TemplateArgument &TA = TAList[i];
1915    StringRef Name;
1916    bool defaultParameter = false;
1917    if (TPList)
1918      Name = TPList->getParam(i)->getName();
1919    switch (TA.getKind()) {
1920    case TemplateArgument::Type: {
1921      llvm::DIType *TTy = getOrCreateType(TA.getAsType(), Unit);
1922
1923      if (TPList)
1924        if (auto *templateType =
1925                dyn_cast_or_null<TemplateTypeParmDecl>(TPList->getParam(i)))
1926          if (templateType->hasDefaultArgument())
1927            defaultParameter =
1928                templateType->getDefaultArgument() == TA.getAsType();
1929
1930      TemplateParams.push_back(DBuilder.createTemplateTypeParameter(
1931          TheCU, Name, TTy, defaultParameter));
1932
1933    } break;
1934    case TemplateArgument::Integral: {
1935      llvm::DIType *TTy = getOrCreateType(TA.getIntegralType(), Unit);
1936      if (TPList && CGM.getCodeGenOpts().DwarfVersion >= 5)
1937        if (auto *templateType =
1938                dyn_cast_or_null<NonTypeTemplateParmDecl>(TPList->getParam(i)))
1939          if (templateType->hasDefaultArgument() &&
1940              !templateType->getDefaultArgument()->isValueDependent())
1941            defaultParameter = llvm::APSInt::isSameValue(
1942                templateType->getDefaultArgument()->EvaluateKnownConstInt(
1943                    CGM.getContext()),
1944                TA.getAsIntegral());
1945
1946      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1947          TheCU, Name, TTy, defaultParameter,
1948          llvm::ConstantInt::get(CGM.getLLVMContext(), TA.getAsIntegral())));
1949    } break;
1950    case TemplateArgument::Declaration: {
1951      const ValueDecl *D = TA.getAsDecl();
1952      QualType T = TA.getParamTypeForDecl().getDesugaredType(CGM.getContext());
1953      llvm::DIType *TTy = getOrCreateType(T, Unit);
1954      llvm::Constant *V = nullptr;
1955      // Skip retrieve the value if that template parameter has cuda device
1956      // attribute, i.e. that value is not available at the host side.
1957      if (!CGM.getLangOpts().CUDA || CGM.getLangOpts().CUDAIsDevice ||
1958          !D->hasAttr<CUDADeviceAttr>()) {
1959        const CXXMethodDecl *MD;
1960        // Variable pointer template parameters have a value that is the address
1961        // of the variable.
1962        if (const auto *VD = dyn_cast<VarDecl>(D))
1963          V = CGM.GetAddrOfGlobalVar(VD);
1964        // Member function pointers have special support for building them,
1965        // though this is currently unsupported in LLVM CodeGen.
1966        else if ((MD = dyn_cast<CXXMethodDecl>(D)) && MD->isInstance())
1967          V = CGM.getCXXABI().EmitMemberFunctionPointer(MD);
1968        else if (const auto *FD = dyn_cast<FunctionDecl>(D))
1969          V = CGM.GetAddrOfFunction(FD);
1970        // Member data pointers have special handling too to compute the fixed
1971        // offset within the object.
1972        else if (const auto *MPT =
1973                     dyn_cast<MemberPointerType>(T.getTypePtr())) {
1974          // These five lines (& possibly the above member function pointer
1975          // handling) might be able to be refactored to use similar code in
1976          // CodeGenModule::getMemberPointerConstant
1977          uint64_t fieldOffset = CGM.getContext().getFieldOffset(D);
1978          CharUnits chars =
1979              CGM.getContext().toCharUnitsFromBits((int64_t)fieldOffset);
1980          V = CGM.getCXXABI().EmitMemberDataPointer(MPT, chars);
1981        } else if (const auto *GD = dyn_cast<MSGuidDecl>(D)) {
1982          V = CGM.GetAddrOfMSGuidDecl(GD).getPointer();
1983        } else if (const auto *TPO = dyn_cast<TemplateParamObjectDecl>(D)) {
1984          if (T->isRecordType())
1985            V = ConstantEmitter(CGM).emitAbstract(
1986                SourceLocation(), TPO->getValue(), TPO->getType());
1987          else
1988            V = CGM.GetAddrOfTemplateParamObject(TPO).getPointer();
1989        }
1990        assert(V && "Failed to find template parameter pointer");
1991        V = V->stripPointerCasts();
1992      }
1993      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
1994          TheCU, Name, TTy, defaultParameter, cast_or_null<llvm::Constant>(V)));
1995    } break;
1996    case TemplateArgument::NullPtr: {
1997      QualType T = TA.getNullPtrType();
1998      llvm::DIType *TTy = getOrCreateType(T, Unit);
1999      llvm::Constant *V = nullptr;
2000      // Special case member data pointer null values since they're actually -1
2001      // instead of zero.
2002      if (const auto *MPT = dyn_cast<MemberPointerType>(T.getTypePtr()))
2003        // But treat member function pointers as simple zero integers because
2004        // it's easier than having a special case in LLVM's CodeGen. If LLVM
2005        // CodeGen grows handling for values of non-null member function
2006        // pointers then perhaps we could remove this special case and rely on
2007        // EmitNullMemberPointer for member function pointers.
2008        if (MPT->isMemberDataPointer())
2009          V = CGM.getCXXABI().EmitNullMemberPointer(MPT);
2010      if (!V)
2011        V = llvm::ConstantInt::get(CGM.Int8Ty, 0);
2012      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
2013          TheCU, Name, TTy, defaultParameter, V));
2014    } break;
2015    case TemplateArgument::Template:
2016      TemplateParams.push_back(DBuilder.createTemplateTemplateParameter(
2017          TheCU, Name, nullptr,
2018          TA.getAsTemplate().getAsTemplateDecl()->getQualifiedNameAsString()));
2019      break;
2020    case TemplateArgument::Pack:
2021      TemplateParams.push_back(DBuilder.createTemplateParameterPack(
2022          TheCU, Name, nullptr,
2023          CollectTemplateParams(nullptr, TA.getPackAsArray(), Unit)));
2024      break;
2025    case TemplateArgument::Expression: {
2026      const Expr *E = TA.getAsExpr();
2027      QualType T = E->getType();
2028      if (E->isGLValue())
2029        T = CGM.getContext().getLValueReferenceType(T);
2030      llvm::Constant *V = ConstantEmitter(CGM).emitAbstract(E, T);
2031      assert(V && "Expression in template argument isn't constant");
2032      llvm::DIType *TTy = getOrCreateType(T, Unit);
2033      TemplateParams.push_back(DBuilder.createTemplateValueParameter(
2034          TheCU, Name, TTy, defaultParameter, V->stripPointerCasts()));
2035    } break;
2036    // And the following should never occur:
2037    case TemplateArgument::TemplateExpansion:
2038    case TemplateArgument::Null:
2039      llvm_unreachable(
2040          "These argument types shouldn't exist in concrete types");
2041    }
2042  }
2043  return DBuilder.getOrCreateArray(TemplateParams);
2044}
2045
2046llvm::DINodeArray
2047CGDebugInfo::CollectFunctionTemplateParams(const FunctionDecl *FD,
2048                                           llvm::DIFile *Unit) {
2049  if (FD->getTemplatedKind() ==
2050      FunctionDecl::TK_FunctionTemplateSpecialization) {
2051    const TemplateParameterList *TList = FD->getTemplateSpecializationInfo()
2052                                             ->getTemplate()
2053                                             ->getTemplateParameters();
2054    return CollectTemplateParams(
2055        TList, FD->getTemplateSpecializationArgs()->asArray(), Unit);
2056  }
2057  return llvm::DINodeArray();
2058}
2059
2060llvm::DINodeArray CGDebugInfo::CollectVarTemplateParams(const VarDecl *VL,
2061                                                        llvm::DIFile *Unit) {
2062  // Always get the full list of parameters, not just the ones from the
2063  // specialization. A partial specialization may have fewer parameters than
2064  // there are arguments.
2065  auto *TS = dyn_cast<VarTemplateSpecializationDecl>(VL);
2066  if (!TS)
2067    return llvm::DINodeArray();
2068  VarTemplateDecl *T = TS->getSpecializedTemplate();
2069  const TemplateParameterList *TList = T->getTemplateParameters();
2070  auto TA = TS->getTemplateArgs().asArray();
2071  return CollectTemplateParams(TList, TA, Unit);
2072}
2073
2074llvm::DINodeArray CGDebugInfo::CollectCXXTemplateParams(
2075    const ClassTemplateSpecializationDecl *TSpecial, llvm::DIFile *Unit) {
2076  // Always get the full list of parameters, not just the ones from the
2077  // specialization. A partial specialization may have fewer parameters than
2078  // there are arguments.
2079  TemplateParameterList *TPList =
2080      TSpecial->getSpecializedTemplate()->getTemplateParameters();
2081  const TemplateArgumentList &TAList = TSpecial->getTemplateArgs();
2082  return CollectTemplateParams(TPList, TAList.asArray(), Unit);
2083}
2084
2085llvm::DIType *CGDebugInfo::getOrCreateVTablePtrType(llvm::DIFile *Unit) {
2086  if (VTablePtrType)
2087    return VTablePtrType;
2088
2089  ASTContext &Context = CGM.getContext();
2090
2091  /* Function type */
2092  llvm::Metadata *STy = getOrCreateType(Context.IntTy, Unit);
2093  llvm::DITypeRefArray SElements = DBuilder.getOrCreateTypeArray(STy);
2094  llvm::DIType *SubTy = DBuilder.createSubroutineType(SElements);
2095  unsigned Size = Context.getTypeSize(Context.VoidPtrTy);
2096  unsigned VtblPtrAddressSpace = CGM.getTarget().getVtblPtrAddressSpace();
2097  Optional<unsigned> DWARFAddressSpace =
2098      CGM.getTarget().getDWARFAddressSpace(VtblPtrAddressSpace);
2099
2100  llvm::DIType *vtbl_ptr_type = DBuilder.createPointerType(
2101      SubTy, Size, 0, DWARFAddressSpace, "__vtbl_ptr_type");
2102  VTablePtrType = DBuilder.createPointerType(vtbl_ptr_type, Size);
2103  return VTablePtrType;
2104}
2105
2106StringRef CGDebugInfo::getVTableName(const CXXRecordDecl *RD) {
2107  // Copy the gdb compatible name on the side and use its reference.
2108  return internString("_vptr$", RD->getNameAsString());
2109}
2110
2111StringRef CGDebugInfo::getDynamicInitializerName(const VarDecl *VD,
2112                                                 DynamicInitKind StubKind,
2113                                                 llvm::Function *InitFn) {
2114  // If we're not emitting codeview, use the mangled name. For Itanium, this is
2115  // arbitrary.
2116  if (!CGM.getCodeGenOpts().EmitCodeView ||
2117      StubKind == DynamicInitKind::GlobalArrayDestructor)
2118    return InitFn->getName();
2119
2120  // Print the normal qualified name for the variable, then break off the last
2121  // NNS, and add the appropriate other text. Clang always prints the global
2122  // variable name without template arguments, so we can use rsplit("::") and
2123  // then recombine the pieces.
2124  SmallString<128> QualifiedGV;
2125  StringRef Quals;
2126  StringRef GVName;
2127  {
2128    llvm::raw_svector_ostream OS(QualifiedGV);
2129    VD->printQualifiedName(OS, getPrintingPolicy());
2130    std::tie(Quals, GVName) = OS.str().rsplit("::");
2131    if (GVName.empty())
2132      std::swap(Quals, GVName);
2133  }
2134
2135  SmallString<128> InitName;
2136  llvm::raw_svector_ostream OS(InitName);
2137  if (!Quals.empty())
2138    OS << Quals << "::";
2139
2140  switch (StubKind) {
2141  case DynamicInitKind::NoStub:
2142  case DynamicInitKind::GlobalArrayDestructor:
2143    llvm_unreachable("not an initializer");
2144  case DynamicInitKind::Initializer:
2145    OS << "`dynamic initializer for '";
2146    break;
2147  case DynamicInitKind::AtExit:
2148    OS << "`dynamic atexit destructor for '";
2149    break;
2150  }
2151
2152  OS << GVName;
2153
2154  // Add any template specialization args.
2155  if (const auto *VTpl = dyn_cast<VarTemplateSpecializationDecl>(VD)) {
2156    printTemplateArgumentList(OS, VTpl->getTemplateArgs().asArray(),
2157                              getPrintingPolicy());
2158  }
2159
2160  OS << '\'';
2161
2162  return internString(OS.str());
2163}
2164
2165void CGDebugInfo::CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile *Unit,
2166                                    SmallVectorImpl<llvm::Metadata *> &EltTys) {
2167  // If this class is not dynamic then there is not any vtable info to collect.
2168  if (!RD->isDynamicClass())
2169    return;
2170
2171  // Don't emit any vtable shape or vptr info if this class doesn't have an
2172  // extendable vfptr. This can happen if the class doesn't have virtual
2173  // methods, or in the MS ABI if those virtual methods only come from virtually
2174  // inherited bases.
2175  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
2176  if (!RL.hasExtendableVFPtr())
2177    return;
2178
2179  // CodeView needs to know how large the vtable of every dynamic class is, so
2180  // emit a special named pointer type into the element list. The vptr type
2181  // points to this type as well.
2182  llvm::DIType *VPtrTy = nullptr;
2183  bool NeedVTableShape = CGM.getCodeGenOpts().EmitCodeView &&
2184                         CGM.getTarget().getCXXABI().isMicrosoft();
2185  if (NeedVTableShape) {
2186    uint64_t PtrWidth =
2187        CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
2188    const VTableLayout &VFTLayout =
2189        CGM.getMicrosoftVTableContext().getVFTableLayout(RD, CharUnits::Zero());
2190    unsigned VSlotCount =
2191        VFTLayout.vtable_components().size() - CGM.getLangOpts().RTTIData;
2192    unsigned VTableWidth = PtrWidth * VSlotCount;
2193    unsigned VtblPtrAddressSpace = CGM.getTarget().getVtblPtrAddressSpace();
2194    Optional<unsigned> DWARFAddressSpace =
2195        CGM.getTarget().getDWARFAddressSpace(VtblPtrAddressSpace);
2196
2197    // Create a very wide void* type and insert it directly in the element list.
2198    llvm::DIType *VTableType = DBuilder.createPointerType(
2199        nullptr, VTableWidth, 0, DWARFAddressSpace, "__vtbl_ptr_type");
2200    EltTys.push_back(VTableType);
2201
2202    // The vptr is a pointer to this special vtable type.
2203    VPtrTy = DBuilder.createPointerType(VTableType, PtrWidth);
2204  }
2205
2206  // If there is a primary base then the artificial vptr member lives there.
2207  if (RL.getPrimaryBase())
2208    return;
2209
2210  if (!VPtrTy)
2211    VPtrTy = getOrCreateVTablePtrType(Unit);
2212
2213  unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
2214  llvm::DIType *VPtrMember =
2215      DBuilder.createMemberType(Unit, getVTableName(RD), Unit, 0, Size, 0, 0,
2216                                llvm::DINode::FlagArtificial, VPtrTy);
2217  EltTys.push_back(VPtrMember);
2218}
2219
2220llvm::DIType *CGDebugInfo::getOrCreateRecordType(QualType RTy,
2221                                                 SourceLocation Loc) {
2222  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
2223  llvm::DIType *T = getOrCreateType(RTy, getOrCreateFile(Loc));
2224  return T;
2225}
2226
2227llvm::DIType *CGDebugInfo::getOrCreateInterfaceType(QualType D,
2228                                                    SourceLocation Loc) {
2229  return getOrCreateStandaloneType(D, Loc);
2230}
2231
2232llvm::DIType *CGDebugInfo::getOrCreateStandaloneType(QualType D,
2233                                                     SourceLocation Loc) {
2234  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
2235  assert(!D.isNull() && "null type");
2236  llvm::DIType *T = getOrCreateType(D, getOrCreateFile(Loc));
2237  assert(T && "could not create debug info for type");
2238
2239  RetainedTypes.push_back(D.getAsOpaquePtr());
2240  return T;
2241}
2242
2243void CGDebugInfo::addHeapAllocSiteMetadata(llvm::CallBase *CI,
2244                                           QualType AllocatedTy,
2245                                           SourceLocation Loc) {
2246  if (CGM.getCodeGenOpts().getDebugInfo() <=
2247      codegenoptions::DebugLineTablesOnly)
2248    return;
2249  llvm::MDNode *node;
2250  if (AllocatedTy->isVoidType())
2251    node = llvm::MDNode::get(CGM.getLLVMContext(), None);
2252  else
2253    node = getOrCreateType(AllocatedTy, getOrCreateFile(Loc));
2254
2255  CI->setMetadata("heapallocsite", node);
2256}
2257
2258void CGDebugInfo::completeType(const EnumDecl *ED) {
2259  if (DebugKind <= codegenoptions::DebugLineTablesOnly)
2260    return;
2261  QualType Ty = CGM.getContext().getEnumType(ED);
2262  void *TyPtr = Ty.getAsOpaquePtr();
2263  auto I = TypeCache.find(TyPtr);
2264  if (I == TypeCache.end() || !cast<llvm::DIType>(I->second)->isForwardDecl())
2265    return;
2266  llvm::DIType *Res = CreateTypeDefinition(Ty->castAs<EnumType>());
2267  assert(!Res->isForwardDecl());
2268  TypeCache[TyPtr].reset(Res);
2269}
2270
2271void CGDebugInfo::completeType(const RecordDecl *RD) {
2272  if (DebugKind > codegenoptions::LimitedDebugInfo ||
2273      !CGM.getLangOpts().CPlusPlus)
2274    completeRequiredType(RD);
2275}
2276
2277/// Return true if the class or any of its methods are marked dllimport.
2278static bool isClassOrMethodDLLImport(const CXXRecordDecl *RD) {
2279  if (RD->hasAttr<DLLImportAttr>())
2280    return true;
2281  for (const CXXMethodDecl *MD : RD->methods())
2282    if (MD->hasAttr<DLLImportAttr>())
2283      return true;
2284  return false;
2285}
2286
2287/// Does a type definition exist in an imported clang module?
2288static bool isDefinedInClangModule(const RecordDecl *RD) {
2289  // Only definitions that where imported from an AST file come from a module.
2290  if (!RD || !RD->isFromASTFile())
2291    return false;
2292  // Anonymous entities cannot be addressed. Treat them as not from module.
2293  if (!RD->isExternallyVisible() && RD->getName().empty())
2294    return false;
2295  if (auto *CXXDecl = dyn_cast<CXXRecordDecl>(RD)) {
2296    if (!CXXDecl->isCompleteDefinition())
2297      return false;
2298    // Check wether RD is a template.
2299    auto TemplateKind = CXXDecl->getTemplateSpecializationKind();
2300    if (TemplateKind != TSK_Undeclared) {
2301      // Unfortunately getOwningModule() isn't accurate enough to find the
2302      // owning module of a ClassTemplateSpecializationDecl that is inside a
2303      // namespace spanning multiple modules.
2304      bool Explicit = false;
2305      if (auto *TD = dyn_cast<ClassTemplateSpecializationDecl>(CXXDecl))
2306        Explicit = TD->isExplicitInstantiationOrSpecialization();
2307      if (!Explicit && CXXDecl->getEnclosingNamespaceContext())
2308        return false;
2309      // This is a template, check the origin of the first member.
2310      if (CXXDecl->field_begin() == CXXDecl->field_end())
2311        return TemplateKind == TSK_ExplicitInstantiationDeclaration;
2312      if (!CXXDecl->field_begin()->isFromASTFile())
2313        return false;
2314    }
2315  }
2316  return true;
2317}
2318
2319void CGDebugInfo::completeClassData(const RecordDecl *RD) {
2320  if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
2321    if (CXXRD->isDynamicClass() &&
2322        CGM.getVTableLinkage(CXXRD) ==
2323            llvm::GlobalValue::AvailableExternallyLinkage &&
2324        !isClassOrMethodDLLImport(CXXRD))
2325      return;
2326
2327  if (DebugTypeExtRefs && isDefinedInClangModule(RD->getDefinition()))
2328    return;
2329
2330  completeClass(RD);
2331}
2332
2333void CGDebugInfo::completeClass(const RecordDecl *RD) {
2334  if (DebugKind <= codegenoptions::DebugLineTablesOnly)
2335    return;
2336  QualType Ty = CGM.getContext().getRecordType(RD);
2337  void *TyPtr = Ty.getAsOpaquePtr();
2338  auto I = TypeCache.find(TyPtr);
2339  if (I != TypeCache.end() && !cast<llvm::DIType>(I->second)->isForwardDecl())
2340    return;
2341  llvm::DIType *Res = CreateTypeDefinition(Ty->castAs<RecordType>());
2342  assert(!Res->isForwardDecl());
2343  TypeCache[TyPtr].reset(Res);
2344}
2345
2346static bool hasExplicitMemberDefinition(CXXRecordDecl::method_iterator I,
2347                                        CXXRecordDecl::method_iterator End) {
2348  for (CXXMethodDecl *MD : llvm::make_range(I, End))
2349    if (FunctionDecl *Tmpl = MD->getInstantiatedFromMemberFunction())
2350      if (!Tmpl->isImplicit() && Tmpl->isThisDeclarationADefinition() &&
2351          !MD->getMemberSpecializationInfo()->isExplicitSpecialization())
2352        return true;
2353  return false;
2354}
2355
2356static bool canUseCtorHoming(const CXXRecordDecl *RD) {
2357  // Constructor homing can be used for classes that cannnot be constructed
2358  // without emitting code for one of their constructors. This is classes that
2359  // don't have trivial or constexpr constructors, or can be created from
2360  // aggregate initialization. Also skip lambda objects because they don't call
2361  // constructors.
2362
2363  // Skip this optimization if the class or any of its methods are marked
2364  // dllimport.
2365  if (isClassOrMethodDLLImport(RD))
2366    return false;
2367
2368  return !RD->isLambda() && !RD->isAggregate() &&
2369         !RD->hasTrivialDefaultConstructor() &&
2370         !RD->hasConstexprNonCopyMoveConstructor();
2371}
2372
2373static bool shouldOmitDefinition(codegenoptions::DebugInfoKind DebugKind,
2374                                 bool DebugTypeExtRefs, const RecordDecl *RD,
2375                                 const LangOptions &LangOpts) {
2376  if (DebugTypeExtRefs && isDefinedInClangModule(RD->getDefinition()))
2377    return true;
2378
2379  if (auto *ES = RD->getASTContext().getExternalSource())
2380    if (ES->hasExternalDefinitions(RD) == ExternalASTSource::EK_Always)
2381      return true;
2382
2383  // Only emit forward declarations in line tables only to keep debug info size
2384  // small. This only applies to CodeView, since we don't emit types in DWARF
2385  // line tables only.
2386  if (DebugKind == codegenoptions::DebugLineTablesOnly)
2387    return true;
2388
2389  if (DebugKind > codegenoptions::LimitedDebugInfo ||
2390      RD->hasAttr<StandaloneDebugAttr>())
2391    return false;
2392
2393  if (!LangOpts.CPlusPlus)
2394    return false;
2395
2396  if (!RD->isCompleteDefinitionRequired())
2397    return true;
2398
2399  const auto *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
2400
2401  if (!CXXDecl)
2402    return false;
2403
2404  // Only emit complete debug info for a dynamic class when its vtable is
2405  // emitted.  However, Microsoft debuggers don't resolve type information
2406  // across DLL boundaries, so skip this optimization if the class or any of its
2407  // methods are marked dllimport. This isn't a complete solution, since objects
2408  // without any dllimport methods can be used in one DLL and constructed in
2409  // another, but it is the current behavior of LimitedDebugInfo.
2410  if (CXXDecl->hasDefinition() && CXXDecl->isDynamicClass() &&
2411      !isClassOrMethodDLLImport(CXXDecl))
2412    return true;
2413
2414  TemplateSpecializationKind Spec = TSK_Undeclared;
2415  if (const auto *SD = dyn_cast<ClassTemplateSpecializationDecl>(RD))
2416    Spec = SD->getSpecializationKind();
2417
2418  if (Spec == TSK_ExplicitInstantiationDeclaration &&
2419      hasExplicitMemberDefinition(CXXDecl->method_begin(),
2420                                  CXXDecl->method_end()))
2421    return true;
2422
2423  // In constructor homing mode, only emit complete debug info for a class
2424  // when its constructor is emitted.
2425  if ((DebugKind == codegenoptions::DebugInfoConstructor) &&
2426      canUseCtorHoming(CXXDecl))
2427    return true;
2428
2429  return false;
2430}
2431
2432void CGDebugInfo::completeRequiredType(const RecordDecl *RD) {
2433  if (shouldOmitDefinition(DebugKind, DebugTypeExtRefs, RD, CGM.getLangOpts()))
2434    return;
2435
2436  QualType Ty = CGM.getContext().getRecordType(RD);
2437  llvm::DIType *T = getTypeOrNull(Ty);
2438  if (T && T->isForwardDecl())
2439    completeClassData(RD);
2440}
2441
2442llvm::DIType *CGDebugInfo::CreateType(const RecordType *Ty) {
2443  RecordDecl *RD = Ty->getDecl();
2444  llvm::DIType *T = cast_or_null<llvm::DIType>(getTypeOrNull(QualType(Ty, 0)));
2445  if (T || shouldOmitDefinition(DebugKind, DebugTypeExtRefs, RD,
2446                                CGM.getLangOpts())) {
2447    if (!T)
2448      T = getOrCreateRecordFwdDecl(Ty, getDeclContextDescriptor(RD));
2449    return T;
2450  }
2451
2452  return CreateTypeDefinition(Ty);
2453}
2454
2455llvm::DIType *CGDebugInfo::CreateTypeDefinition(const RecordType *Ty) {
2456  RecordDecl *RD = Ty->getDecl();
2457
2458  // Get overall information about the record type for the debug info.
2459  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
2460
2461  // Records and classes and unions can all be recursive.  To handle them, we
2462  // first generate a debug descriptor for the struct as a forward declaration.
2463  // Then (if it is a definition) we go through and get debug info for all of
2464  // its members.  Finally, we create a descriptor for the complete type (which
2465  // may refer to the forward decl if the struct is recursive) and replace all
2466  // uses of the forward declaration with the final definition.
2467  llvm::DICompositeType *FwdDecl = getOrCreateLimitedType(Ty);
2468
2469  const RecordDecl *D = RD->getDefinition();
2470  if (!D || !D->isCompleteDefinition())
2471    return FwdDecl;
2472
2473  if (const auto *CXXDecl = dyn_cast<CXXRecordDecl>(RD))
2474    CollectContainingType(CXXDecl, FwdDecl);
2475
2476  // Push the struct on region stack.
2477  LexicalBlockStack.emplace_back(&*FwdDecl);
2478  RegionMap[Ty->getDecl()].reset(FwdDecl);
2479
2480  // Convert all the elements.
2481  SmallVector<llvm::Metadata *, 16> EltTys;
2482  // what about nested types?
2483
2484  // Note: The split of CXXDecl information here is intentional, the
2485  // gdb tests will depend on a certain ordering at printout. The debug
2486  // information offsets are still correct if we merge them all together
2487  // though.
2488  const auto *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
2489  if (CXXDecl) {
2490    CollectCXXBases(CXXDecl, DefUnit, EltTys, FwdDecl);
2491    CollectVTableInfo(CXXDecl, DefUnit, EltTys);
2492  }
2493
2494  // Collect data fields (including static variables and any initializers).
2495  CollectRecordFields(RD, DefUnit, EltTys, FwdDecl);
2496  if (CXXDecl)
2497    CollectCXXMemberFunctions(CXXDecl, DefUnit, EltTys, FwdDecl);
2498
2499  LexicalBlockStack.pop_back();
2500  RegionMap.erase(Ty->getDecl());
2501
2502  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
2503  DBuilder.replaceArrays(FwdDecl, Elements);
2504
2505  if (FwdDecl->isTemporary())
2506    FwdDecl =
2507        llvm::MDNode::replaceWithPermanent(llvm::TempDICompositeType(FwdDecl));
2508
2509  RegionMap[Ty->getDecl()].reset(FwdDecl);
2510  return FwdDecl;
2511}
2512
2513llvm::DIType *CGDebugInfo::CreateType(const ObjCObjectType *Ty,
2514                                      llvm::DIFile *Unit) {
2515  // Ignore protocols.
2516  return getOrCreateType(Ty->getBaseType(), Unit);
2517}
2518
2519llvm::DIType *CGDebugInfo::CreateType(const ObjCTypeParamType *Ty,
2520                                      llvm::DIFile *Unit) {
2521  // Ignore protocols.
2522  SourceLocation Loc = Ty->getDecl()->getLocation();
2523
2524  // Use Typedefs to represent ObjCTypeParamType.
2525  return DBuilder.createTypedef(
2526      getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit),
2527      Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc),
2528      getDeclContextDescriptor(Ty->getDecl()));
2529}
2530
2531/// \return true if Getter has the default name for the property PD.
2532static bool hasDefaultGetterName(const ObjCPropertyDecl *PD,
2533                                 const ObjCMethodDecl *Getter) {
2534  assert(PD);
2535  if (!Getter)
2536    return true;
2537
2538  assert(Getter->getDeclName().isObjCZeroArgSelector());
2539  return PD->getName() ==
2540         Getter->getDeclName().getObjCSelector().getNameForSlot(0);
2541}
2542
2543/// \return true if Setter has the default name for the property PD.
2544static bool hasDefaultSetterName(const ObjCPropertyDecl *PD,
2545                                 const ObjCMethodDecl *Setter) {
2546  assert(PD);
2547  if (!Setter)
2548    return true;
2549
2550  assert(Setter->getDeclName().isObjCOneArgSelector());
2551  return SelectorTable::constructSetterName(PD->getName()) ==
2552         Setter->getDeclName().getObjCSelector().getNameForSlot(0);
2553}
2554
2555llvm::DIType *CGDebugInfo::CreateType(const ObjCInterfaceType *Ty,
2556                                      llvm::DIFile *Unit) {
2557  ObjCInterfaceDecl *ID = Ty->getDecl();
2558  if (!ID)
2559    return nullptr;
2560
2561  // Return a forward declaration if this type was imported from a clang module,
2562  // and this is not the compile unit with the implementation of the type (which
2563  // may contain hidden ivars).
2564  if (DebugTypeExtRefs && ID->isFromASTFile() && ID->getDefinition() &&
2565      !ID->getImplementation())
2566    return DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_structure_type,
2567                                      ID->getName(),
2568                                      getDeclContextDescriptor(ID), Unit, 0);
2569
2570  // Get overall information about the record type for the debug info.
2571  llvm::DIFile *DefUnit = getOrCreateFile(ID->getLocation());
2572  unsigned Line = getLineNumber(ID->getLocation());
2573  auto RuntimeLang =
2574      static_cast<llvm::dwarf::SourceLanguage>(TheCU->getSourceLanguage());
2575
2576  // If this is just a forward declaration return a special forward-declaration
2577  // debug type since we won't be able to lay out the entire type.
2578  ObjCInterfaceDecl *Def = ID->getDefinition();
2579  if (!Def || !Def->getImplementation()) {
2580    llvm::DIScope *Mod = getParentModuleOrNull(ID);
2581    llvm::DIType *FwdDecl = DBuilder.createReplaceableCompositeType(
2582        llvm::dwarf::DW_TAG_structure_type, ID->getName(), Mod ? Mod : TheCU,
2583        DefUnit, Line, RuntimeLang);
2584    ObjCInterfaceCache.push_back(ObjCInterfaceCacheEntry(Ty, FwdDecl, Unit));
2585    return FwdDecl;
2586  }
2587
2588  return CreateTypeDefinition(Ty, Unit);
2589}
2590
2591llvm::DIModule *CGDebugInfo::getOrCreateModuleRef(ASTSourceDescriptor Mod,
2592                                                  bool CreateSkeletonCU) {
2593  // Use the Module pointer as the key into the cache. This is a
2594  // nullptr if the "Module" is a PCH, which is safe because we don't
2595  // support chained PCH debug info, so there can only be a single PCH.
2596  const Module *M = Mod.getModuleOrNull();
2597  auto ModRef = ModuleCache.find(M);
2598  if (ModRef != ModuleCache.end())
2599    return cast<llvm::DIModule>(ModRef->second);
2600
2601  // Macro definitions that were defined with "-D" on the command line.
2602  SmallString<128> ConfigMacros;
2603  {
2604    llvm::raw_svector_ostream OS(ConfigMacros);
2605    const auto &PPOpts = CGM.getPreprocessorOpts();
2606    unsigned I = 0;
2607    // Translate the macro definitions back into a command line.
2608    for (auto &M : PPOpts.Macros) {
2609      if (++I > 1)
2610        OS << " ";
2611      const std::string &Macro = M.first;
2612      bool Undef = M.second;
2613      OS << "\"-" << (Undef ? 'U' : 'D');
2614      for (char c : Macro)
2615        switch (c) {
2616        case '\\':
2617          OS << "\\\\";
2618          break;
2619        case '"':
2620          OS << "\\\"";
2621          break;
2622        default:
2623          OS << c;
2624        }
2625      OS << '\"';
2626    }
2627  }
2628
2629  bool IsRootModule = M ? !M->Parent : true;
2630  // When a module name is specified as -fmodule-name, that module gets a
2631  // clang::Module object, but it won't actually be built or imported; it will
2632  // be textual.
2633  if (CreateSkeletonCU && IsRootModule && Mod.getASTFile().empty() && M)
2634    assert(StringRef(M->Name).startswith(CGM.getLangOpts().ModuleName) &&
2635           "clang module without ASTFile must be specified by -fmodule-name");
2636
2637  // Return a StringRef to the remapped Path.
2638  auto RemapPath = [this](StringRef Path) -> std::string {
2639    std::string Remapped = remapDIPath(Path);
2640    StringRef Relative(Remapped);
2641    StringRef CompDir = TheCU->getDirectory();
2642    if (Relative.consume_front(CompDir))
2643      Relative.consume_front(llvm::sys::path::get_separator());
2644
2645    return Relative.str();
2646  };
2647
2648  if (CreateSkeletonCU && IsRootModule && !Mod.getASTFile().empty()) {
2649    // PCH files don't have a signature field in the control block,
2650    // but LLVM detects skeleton CUs by looking for a non-zero DWO id.
2651    // We use the lower 64 bits for debug info.
2652
2653    uint64_t Signature = 0;
2654    if (const auto &ModSig = Mod.getSignature())
2655      Signature = ModSig.truncatedValue();
2656    else
2657      Signature = ~1ULL;
2658
2659    llvm::DIBuilder DIB(CGM.getModule());
2660    SmallString<0> PCM;
2661    if (!llvm::sys::path::is_absolute(Mod.getASTFile()))
2662      PCM = Mod.getPath();
2663    llvm::sys::path::append(PCM, Mod.getASTFile());
2664    DIB.createCompileUnit(
2665        TheCU->getSourceLanguage(),
2666        // TODO: Support "Source" from external AST providers?
2667        DIB.createFile(Mod.getModuleName(), TheCU->getDirectory()),
2668        TheCU->getProducer(), false, StringRef(), 0, RemapPath(PCM),
2669        llvm::DICompileUnit::FullDebug, Signature);
2670    DIB.finalize();
2671  }
2672
2673  llvm::DIModule *Parent =
2674      IsRootModule ? nullptr
2675                   : getOrCreateModuleRef(ASTSourceDescriptor(*M->Parent),
2676                                          CreateSkeletonCU);
2677  std::string IncludePath = Mod.getPath().str();
2678  llvm::DIModule *DIMod =
2679      DBuilder.createModule(Parent, Mod.getModuleName(), ConfigMacros,
2680                            RemapPath(IncludePath));
2681  ModuleCache[M].reset(DIMod);
2682  return DIMod;
2683}
2684
2685llvm::DIType *CGDebugInfo::CreateTypeDefinition(const ObjCInterfaceType *Ty,
2686                                                llvm::DIFile *Unit) {
2687  ObjCInterfaceDecl *ID = Ty->getDecl();
2688  llvm::DIFile *DefUnit = getOrCreateFile(ID->getLocation());
2689  unsigned Line = getLineNumber(ID->getLocation());
2690  unsigned RuntimeLang = TheCU->getSourceLanguage();
2691
2692  // Bit size, align and offset of the type.
2693  uint64_t Size = CGM.getContext().getTypeSize(Ty);
2694  auto Align = getTypeAlignIfRequired(Ty, CGM.getContext());
2695
2696  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
2697  if (ID->getImplementation())
2698    Flags |= llvm::DINode::FlagObjcClassComplete;
2699
2700  llvm::DIScope *Mod = getParentModuleOrNull(ID);
2701  llvm::DICompositeType *RealDecl = DBuilder.createStructType(
2702      Mod ? Mod : Unit, ID->getName(), DefUnit, Line, Size, Align, Flags,
2703      nullptr, llvm::DINodeArray(), RuntimeLang);
2704
2705  QualType QTy(Ty, 0);
2706  TypeCache[QTy.getAsOpaquePtr()].reset(RealDecl);
2707
2708  // Push the struct on region stack.
2709  LexicalBlockStack.emplace_back(RealDecl);
2710  RegionMap[Ty->getDecl()].reset(RealDecl);
2711
2712  // Convert all the elements.
2713  SmallVector<llvm::Metadata *, 16> EltTys;
2714
2715  ObjCInterfaceDecl *SClass = ID->getSuperClass();
2716  if (SClass) {
2717    llvm::DIType *SClassTy =
2718        getOrCreateType(CGM.getContext().getObjCInterfaceType(SClass), Unit);
2719    if (!SClassTy)
2720      return nullptr;
2721
2722    llvm::DIType *InhTag = DBuilder.createInheritance(RealDecl, SClassTy, 0, 0,
2723                                                      llvm::DINode::FlagZero);
2724    EltTys.push_back(InhTag);
2725  }
2726
2727  // Create entries for all of the properties.
2728  auto AddProperty = [&](const ObjCPropertyDecl *PD) {
2729    SourceLocation Loc = PD->getLocation();
2730    llvm::DIFile *PUnit = getOrCreateFile(Loc);
2731    unsigned PLine = getLineNumber(Loc);
2732    ObjCMethodDecl *Getter = PD->getGetterMethodDecl();
2733    ObjCMethodDecl *Setter = PD->getSetterMethodDecl();
2734    llvm::MDNode *PropertyNode = DBuilder.createObjCProperty(
2735        PD->getName(), PUnit, PLine,
2736        hasDefaultGetterName(PD, Getter) ? ""
2737                                         : getSelectorName(PD->getGetterName()),
2738        hasDefaultSetterName(PD, Setter) ? ""
2739                                         : getSelectorName(PD->getSetterName()),
2740        PD->getPropertyAttributes(), getOrCreateType(PD->getType(), PUnit));
2741    EltTys.push_back(PropertyNode);
2742  };
2743  {
2744    // Use 'char' for the isClassProperty bit as DenseSet requires space for
2745    // empty/tombstone keys in the data type (and bool is too small for that).
2746    typedef std::pair<char, const IdentifierInfo *> IsClassAndIdent;
2747    /// List of already emitted properties. Two distinct class and instance
2748    /// properties can share the same identifier (but not two instance
2749    /// properties or two class properties).
2750    llvm::DenseSet<IsClassAndIdent> PropertySet;
2751    /// Returns the IsClassAndIdent key for the given property.
2752    auto GetIsClassAndIdent = [](const ObjCPropertyDecl *PD) {
2753      return std::make_pair(PD->isClassProperty(), PD->getIdentifier());
2754    };
2755    for (const ObjCCategoryDecl *ClassExt : ID->known_extensions())
2756      for (auto *PD : ClassExt->properties()) {
2757        PropertySet.insert(GetIsClassAndIdent(PD));
2758        AddProperty(PD);
2759      }
2760    for (const auto *PD : ID->properties()) {
2761      // Don't emit duplicate metadata for properties that were already in a
2762      // class extension.
2763      if (!PropertySet.insert(GetIsClassAndIdent(PD)).second)
2764        continue;
2765      AddProperty(PD);
2766    }
2767  }
2768
2769  const ASTRecordLayout &RL = CGM.getContext().getASTObjCInterfaceLayout(ID);
2770  unsigned FieldNo = 0;
2771  for (ObjCIvarDecl *Field = ID->all_declared_ivar_begin(); Field;
2772       Field = Field->getNextIvar(), ++FieldNo) {
2773    llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
2774    if (!FieldTy)
2775      return nullptr;
2776
2777    StringRef FieldName = Field->getName();
2778
2779    // Ignore unnamed fields.
2780    if (FieldName.empty())
2781      continue;
2782
2783    // Get the location for the field.
2784    llvm::DIFile *FieldDefUnit = getOrCreateFile(Field->getLocation());
2785    unsigned FieldLine = getLineNumber(Field->getLocation());
2786    QualType FType = Field->getType();
2787    uint64_t FieldSize = 0;
2788    uint32_t FieldAlign = 0;
2789
2790    if (!FType->isIncompleteArrayType()) {
2791
2792      // Bit size, align and offset of the type.
2793      FieldSize = Field->isBitField()
2794                      ? Field->getBitWidthValue(CGM.getContext())
2795                      : CGM.getContext().getTypeSize(FType);
2796      FieldAlign = getTypeAlignIfRequired(FType, CGM.getContext());
2797    }
2798
2799    uint64_t FieldOffset;
2800    if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
2801      // We don't know the runtime offset of an ivar if we're using the
2802      // non-fragile ABI.  For bitfields, use the bit offset into the first
2803      // byte of storage of the bitfield.  For other fields, use zero.
2804      if (Field->isBitField()) {
2805        FieldOffset =
2806            CGM.getObjCRuntime().ComputeBitfieldBitOffset(CGM, ID, Field);
2807        FieldOffset %= CGM.getContext().getCharWidth();
2808      } else {
2809        FieldOffset = 0;
2810      }
2811    } else {
2812      FieldOffset = RL.getFieldOffset(FieldNo);
2813    }
2814
2815    llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
2816    if (Field->getAccessControl() == ObjCIvarDecl::Protected)
2817      Flags = llvm::DINode::FlagProtected;
2818    else if (Field->getAccessControl() == ObjCIvarDecl::Private)
2819      Flags = llvm::DINode::FlagPrivate;
2820    else if (Field->getAccessControl() == ObjCIvarDecl::Public)
2821      Flags = llvm::DINode::FlagPublic;
2822
2823    llvm::MDNode *PropertyNode = nullptr;
2824    if (ObjCImplementationDecl *ImpD = ID->getImplementation()) {
2825      if (ObjCPropertyImplDecl *PImpD =
2826              ImpD->FindPropertyImplIvarDecl(Field->getIdentifier())) {
2827        if (ObjCPropertyDecl *PD = PImpD->getPropertyDecl()) {
2828          SourceLocation Loc = PD->getLocation();
2829          llvm::DIFile *PUnit = getOrCreateFile(Loc);
2830          unsigned PLine = getLineNumber(Loc);
2831          ObjCMethodDecl *Getter = PImpD->getGetterMethodDecl();
2832          ObjCMethodDecl *Setter = PImpD->getSetterMethodDecl();
2833          PropertyNode = DBuilder.createObjCProperty(
2834              PD->getName(), PUnit, PLine,
2835              hasDefaultGetterName(PD, Getter)
2836                  ? ""
2837                  : getSelectorName(PD->getGetterName()),
2838              hasDefaultSetterName(PD, Setter)
2839                  ? ""
2840                  : getSelectorName(PD->getSetterName()),
2841              PD->getPropertyAttributes(),
2842              getOrCreateType(PD->getType(), PUnit));
2843        }
2844      }
2845    }
2846    FieldTy = DBuilder.createObjCIVar(FieldName, FieldDefUnit, FieldLine,
2847                                      FieldSize, FieldAlign, FieldOffset, Flags,
2848                                      FieldTy, PropertyNode);
2849    EltTys.push_back(FieldTy);
2850  }
2851
2852  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
2853  DBuilder.replaceArrays(RealDecl, Elements);
2854
2855  LexicalBlockStack.pop_back();
2856  return RealDecl;
2857}
2858
2859llvm::DIType *CGDebugInfo::CreateType(const VectorType *Ty,
2860                                      llvm::DIFile *Unit) {
2861  llvm::DIType *ElementTy = getOrCreateType(Ty->getElementType(), Unit);
2862  int64_t Count = Ty->getNumElements();
2863
2864  llvm::Metadata *Subscript;
2865  QualType QTy(Ty, 0);
2866  auto SizeExpr = SizeExprCache.find(QTy);
2867  if (SizeExpr != SizeExprCache.end())
2868    Subscript = DBuilder.getOrCreateSubrange(
2869        SizeExpr->getSecond() /*count*/, nullptr /*lowerBound*/,
2870        nullptr /*upperBound*/, nullptr /*stride*/);
2871  else {
2872    auto *CountNode =
2873        llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
2874            llvm::Type::getInt64Ty(CGM.getLLVMContext()), Count ? Count : -1));
2875    Subscript = DBuilder.getOrCreateSubrange(
2876        CountNode /*count*/, nullptr /*lowerBound*/, nullptr /*upperBound*/,
2877        nullptr /*stride*/);
2878  }
2879  llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscript);
2880
2881  uint64_t Size = CGM.getContext().getTypeSize(Ty);
2882  auto Align = getTypeAlignIfRequired(Ty, CGM.getContext());
2883
2884  return DBuilder.createVectorType(Size, Align, ElementTy, SubscriptArray);
2885}
2886
2887llvm::DIType *CGDebugInfo::CreateType(const ConstantMatrixType *Ty,
2888                                      llvm::DIFile *Unit) {
2889  // FIXME: Create another debug type for matrices
2890  // For the time being, it treats it like a nested ArrayType.
2891
2892  llvm::DIType *ElementTy = getOrCreateType(Ty->getElementType(), Unit);
2893  uint64_t Size = CGM.getContext().getTypeSize(Ty);
2894  uint32_t Align = getTypeAlignIfRequired(Ty, CGM.getContext());
2895
2896  // Create ranges for both dimensions.
2897  llvm::SmallVector<llvm::Metadata *, 2> Subscripts;
2898  auto *ColumnCountNode =
2899      llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
2900          llvm::Type::getInt64Ty(CGM.getLLVMContext()), Ty->getNumColumns()));
2901  auto *RowCountNode =
2902      llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
2903          llvm::Type::getInt64Ty(CGM.getLLVMContext()), Ty->getNumRows()));
2904  Subscripts.push_back(DBuilder.getOrCreateSubrange(
2905      ColumnCountNode /*count*/, nullptr /*lowerBound*/, nullptr /*upperBound*/,
2906      nullptr /*stride*/));
2907  Subscripts.push_back(DBuilder.getOrCreateSubrange(
2908      RowCountNode /*count*/, nullptr /*lowerBound*/, nullptr /*upperBound*/,
2909      nullptr /*stride*/));
2910  llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscripts);
2911  return DBuilder.createArrayType(Size, Align, ElementTy, SubscriptArray);
2912}
2913
2914llvm::DIType *CGDebugInfo::CreateType(const ArrayType *Ty, llvm::DIFile *Unit) {
2915  uint64_t Size;
2916  uint32_t Align;
2917
2918  // FIXME: make getTypeAlign() aware of VLAs and incomplete array types
2919  if (const auto *VAT = dyn_cast<VariableArrayType>(Ty)) {
2920    Size = 0;
2921    Align = getTypeAlignIfRequired(CGM.getContext().getBaseElementType(VAT),
2922                                   CGM.getContext());
2923  } else if (Ty->isIncompleteArrayType()) {
2924    Size = 0;
2925    if (Ty->getElementType()->isIncompleteType())
2926      Align = 0;
2927    else
2928      Align = getTypeAlignIfRequired(Ty->getElementType(), CGM.getContext());
2929  } else if (Ty->isIncompleteType()) {
2930    Size = 0;
2931    Align = 0;
2932  } else {
2933    // Size and align of the whole array, not the element type.
2934    Size = CGM.getContext().getTypeSize(Ty);
2935    Align = getTypeAlignIfRequired(Ty, CGM.getContext());
2936  }
2937
2938  // Add the dimensions of the array.  FIXME: This loses CV qualifiers from
2939  // interior arrays, do we care?  Why aren't nested arrays represented the
2940  // obvious/recursive way?
2941  SmallVector<llvm::Metadata *, 8> Subscripts;
2942  QualType EltTy(Ty, 0);
2943  while ((Ty = dyn_cast<ArrayType>(EltTy))) {
2944    // If the number of elements is known, then count is that number. Otherwise,
2945    // it's -1. This allows us to represent a subrange with an array of 0
2946    // elements, like this:
2947    //
2948    //   struct foo {
2949    //     int x[0];
2950    //   };
2951    int64_t Count = -1; // Count == -1 is an unbounded array.
2952    if (const auto *CAT = dyn_cast<ConstantArrayType>(Ty))
2953      Count = CAT->getSize().getZExtValue();
2954    else if (const auto *VAT = dyn_cast<VariableArrayType>(Ty)) {
2955      if (Expr *Size = VAT->getSizeExpr()) {
2956        Expr::EvalResult Result;
2957        if (Size->EvaluateAsInt(Result, CGM.getContext()))
2958          Count = Result.Val.getInt().getExtValue();
2959      }
2960    }
2961
2962    auto SizeNode = SizeExprCache.find(EltTy);
2963    if (SizeNode != SizeExprCache.end())
2964      Subscripts.push_back(DBuilder.getOrCreateSubrange(
2965          SizeNode->getSecond() /*count*/, nullptr /*lowerBound*/,
2966          nullptr /*upperBound*/, nullptr /*stride*/));
2967    else {
2968      auto *CountNode =
2969          llvm::ConstantAsMetadata::get(llvm::ConstantInt::getSigned(
2970              llvm::Type::getInt64Ty(CGM.getLLVMContext()), Count));
2971      Subscripts.push_back(DBuilder.getOrCreateSubrange(
2972          CountNode /*count*/, nullptr /*lowerBound*/, nullptr /*upperBound*/,
2973          nullptr /*stride*/));
2974    }
2975    EltTy = Ty->getElementType();
2976  }
2977
2978  llvm::DINodeArray SubscriptArray = DBuilder.getOrCreateArray(Subscripts);
2979
2980  return DBuilder.createArrayType(Size, Align, getOrCreateType(EltTy, Unit),
2981                                  SubscriptArray);
2982}
2983
2984llvm::DIType *CGDebugInfo::CreateType(const LValueReferenceType *Ty,
2985                                      llvm::DIFile *Unit) {
2986  return CreatePointerLikeType(llvm::dwarf::DW_TAG_reference_type, Ty,
2987                               Ty->getPointeeType(), Unit);
2988}
2989
2990llvm::DIType *CGDebugInfo::CreateType(const RValueReferenceType *Ty,
2991                                      llvm::DIFile *Unit) {
2992  return CreatePointerLikeType(llvm::dwarf::DW_TAG_rvalue_reference_type, Ty,
2993                               Ty->getPointeeType(), Unit);
2994}
2995
2996llvm::DIType *CGDebugInfo::CreateType(const MemberPointerType *Ty,
2997                                      llvm::DIFile *U) {
2998  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
2999  uint64_t Size = 0;
3000
3001  if (!Ty->isIncompleteType()) {
3002    Size = CGM.getContext().getTypeSize(Ty);
3003
3004    // Set the MS inheritance model. There is no flag for the unspecified model.
3005    if (CGM.getTarget().getCXXABI().isMicrosoft()) {
3006      switch (Ty->getMostRecentCXXRecordDecl()->getMSInheritanceModel()) {
3007      case MSInheritanceModel::Single:
3008        Flags |= llvm::DINode::FlagSingleInheritance;
3009        break;
3010      case MSInheritanceModel::Multiple:
3011        Flags |= llvm::DINode::FlagMultipleInheritance;
3012        break;
3013      case MSInheritanceModel::Virtual:
3014        Flags |= llvm::DINode::FlagVirtualInheritance;
3015        break;
3016      case MSInheritanceModel::Unspecified:
3017        break;
3018      }
3019    }
3020  }
3021
3022  llvm::DIType *ClassType = getOrCreateType(QualType(Ty->getClass(), 0), U);
3023  if (Ty->isMemberDataPointerType())
3024    return DBuilder.createMemberPointerType(
3025        getOrCreateType(Ty->getPointeeType(), U), ClassType, Size, /*Align=*/0,
3026        Flags);
3027
3028  const FunctionProtoType *FPT =
3029      Ty->getPointeeType()->getAs<FunctionProtoType>();
3030  return DBuilder.createMemberPointerType(
3031      getOrCreateInstanceMethodType(
3032          CXXMethodDecl::getThisType(FPT, Ty->getMostRecentCXXRecordDecl()),
3033          FPT, U, false),
3034      ClassType, Size, /*Align=*/0, Flags);
3035}
3036
3037llvm::DIType *CGDebugInfo::CreateType(const AtomicType *Ty, llvm::DIFile *U) {
3038  auto *FromTy = getOrCreateType(Ty->getValueType(), U);
3039  return DBuilder.createQualifiedType(llvm::dwarf::DW_TAG_atomic_type, FromTy);
3040}
3041
3042llvm::DIType *CGDebugInfo::CreateType(const PipeType *Ty, llvm::DIFile *U) {
3043  return getOrCreateType(Ty->getElementType(), U);
3044}
3045
3046llvm::DIType *CGDebugInfo::CreateEnumType(const EnumType *Ty) {
3047  const EnumDecl *ED = Ty->getDecl();
3048
3049  uint64_t Size = 0;
3050  uint32_t Align = 0;
3051  if (!ED->getTypeForDecl()->isIncompleteType()) {
3052    Size = CGM.getContext().getTypeSize(ED->getTypeForDecl());
3053    Align = getDeclAlignIfRequired(ED, CGM.getContext());
3054  }
3055
3056  SmallString<256> Identifier = getTypeIdentifier(Ty, CGM, TheCU);
3057
3058  bool isImportedFromModule =
3059      DebugTypeExtRefs && ED->isFromASTFile() && ED->getDefinition();
3060
3061  // If this is just a forward declaration, construct an appropriately
3062  // marked node and just return it.
3063  if (isImportedFromModule || !ED->getDefinition()) {
3064    // Note that it is possible for enums to be created as part of
3065    // their own declcontext. In this case a FwdDecl will be created
3066    // twice. This doesn't cause a problem because both FwdDecls are
3067    // entered into the ReplaceMap: finalize() will replace the first
3068    // FwdDecl with the second and then replace the second with
3069    // complete type.
3070    llvm::DIScope *EDContext = getDeclContextDescriptor(ED);
3071    llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
3072    llvm::TempDIScope TmpContext(DBuilder.createReplaceableCompositeType(
3073        llvm::dwarf::DW_TAG_enumeration_type, "", TheCU, DefUnit, 0));
3074
3075    unsigned Line = getLineNumber(ED->getLocation());
3076    StringRef EDName = ED->getName();
3077    llvm::DIType *RetTy = DBuilder.createReplaceableCompositeType(
3078        llvm::dwarf::DW_TAG_enumeration_type, EDName, EDContext, DefUnit, Line,
3079        0, Size, Align, llvm::DINode::FlagFwdDecl, Identifier);
3080
3081    ReplaceMap.emplace_back(
3082        std::piecewise_construct, std::make_tuple(Ty),
3083        std::make_tuple(static_cast<llvm::Metadata *>(RetTy)));
3084    return RetTy;
3085  }
3086
3087  return CreateTypeDefinition(Ty);
3088}
3089
3090llvm::DIType *CGDebugInfo::CreateTypeDefinition(const EnumType *Ty) {
3091  const EnumDecl *ED = Ty->getDecl();
3092  uint64_t Size = 0;
3093  uint32_t Align = 0;
3094  if (!ED->getTypeForDecl()->isIncompleteType()) {
3095    Size = CGM.getContext().getTypeSize(ED->getTypeForDecl());
3096    Align = getDeclAlignIfRequired(ED, CGM.getContext());
3097  }
3098
3099  SmallString<256> Identifier = getTypeIdentifier(Ty, CGM, TheCU);
3100
3101  // Create elements for each enumerator.
3102  SmallVector<llvm::Metadata *, 16> Enumerators;
3103  ED = ED->getDefinition();
3104  bool IsSigned = ED->getIntegerType()->isSignedIntegerType();
3105  for (const auto *Enum : ED->enumerators()) {
3106    const auto &InitVal = Enum->getInitVal();
3107    auto Value = IsSigned ? InitVal.getSExtValue() : InitVal.getZExtValue();
3108    Enumerators.push_back(
3109        DBuilder.createEnumerator(Enum->getName(), Value, !IsSigned));
3110  }
3111
3112  // Return a CompositeType for the enum itself.
3113  llvm::DINodeArray EltArray = DBuilder.getOrCreateArray(Enumerators);
3114
3115  llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
3116  unsigned Line = getLineNumber(ED->getLocation());
3117  llvm::DIScope *EnumContext = getDeclContextDescriptor(ED);
3118  llvm::DIType *ClassTy = getOrCreateType(ED->getIntegerType(), DefUnit);
3119  return DBuilder.createEnumerationType(EnumContext, ED->getName(), DefUnit,
3120                                        Line, Size, Align, EltArray, ClassTy,
3121                                        Identifier, ED->isScoped());
3122}
3123
3124llvm::DIMacro *CGDebugInfo::CreateMacro(llvm::DIMacroFile *Parent,
3125                                        unsigned MType, SourceLocation LineLoc,
3126                                        StringRef Name, StringRef Value) {
3127  unsigned Line = LineLoc.isInvalid() ? 0 : getLineNumber(LineLoc);
3128  return DBuilder.createMacro(Parent, Line, MType, Name, Value);
3129}
3130
3131llvm::DIMacroFile *CGDebugInfo::CreateTempMacroFile(llvm::DIMacroFile *Parent,
3132                                                    SourceLocation LineLoc,
3133                                                    SourceLocation FileLoc) {
3134  llvm::DIFile *FName = getOrCreateFile(FileLoc);
3135  unsigned Line = LineLoc.isInvalid() ? 0 : getLineNumber(LineLoc);
3136  return DBuilder.createTempMacroFile(Parent, Line, FName);
3137}
3138
3139static QualType UnwrapTypeForDebugInfo(QualType T, const ASTContext &C) {
3140  Qualifiers Quals;
3141  do {
3142    Qualifiers InnerQuals = T.getLocalQualifiers();
3143    // Qualifiers::operator+() doesn't like it if you add a Qualifier
3144    // that is already there.
3145    Quals += Qualifiers::removeCommonQualifiers(Quals, InnerQuals);
3146    Quals += InnerQuals;
3147    QualType LastT = T;
3148    switch (T->getTypeClass()) {
3149    default:
3150      return C.getQualifiedType(T.getTypePtr(), Quals);
3151    case Type::TemplateSpecialization: {
3152      const auto *Spec = cast<TemplateSpecializationType>(T);
3153      if (Spec->isTypeAlias())
3154        return C.getQualifiedType(T.getTypePtr(), Quals);
3155      T = Spec->desugar();
3156      break;
3157    }
3158    case Type::TypeOfExpr:
3159      T = cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType();
3160      break;
3161    case Type::TypeOf:
3162      T = cast<TypeOfType>(T)->getUnderlyingType();
3163      break;
3164    case Type::Decltype:
3165      T = cast<DecltypeType>(T)->getUnderlyingType();
3166      break;
3167    case Type::UnaryTransform:
3168      T = cast<UnaryTransformType>(T)->getUnderlyingType();
3169      break;
3170    case Type::Attributed:
3171      T = cast<AttributedType>(T)->getEquivalentType();
3172      break;
3173    case Type::Elaborated:
3174      T = cast<ElaboratedType>(T)->getNamedType();
3175      break;
3176    case Type::Paren:
3177      T = cast<ParenType>(T)->getInnerType();
3178      break;
3179    case Type::MacroQualified:
3180      T = cast<MacroQualifiedType>(T)->getUnderlyingType();
3181      break;
3182    case Type::SubstTemplateTypeParm:
3183      T = cast<SubstTemplateTypeParmType>(T)->getReplacementType();
3184      break;
3185    case Type::Auto:
3186    case Type::DeducedTemplateSpecialization: {
3187      QualType DT = cast<DeducedType>(T)->getDeducedType();
3188      assert(!DT.isNull() && "Undeduced types shouldn't reach here.");
3189      T = DT;
3190      break;
3191    }
3192    case Type::Adjusted:
3193    case Type::Decayed:
3194      // Decayed and adjusted types use the adjusted type in LLVM and DWARF.
3195      T = cast<AdjustedType>(T)->getAdjustedType();
3196      break;
3197    }
3198
3199    assert(T != LastT && "Type unwrapping failed to unwrap!");
3200    (void)LastT;
3201  } while (true);
3202}
3203
3204llvm::DIType *CGDebugInfo::getTypeOrNull(QualType Ty) {
3205  assert(Ty == UnwrapTypeForDebugInfo(Ty, CGM.getContext()));
3206  auto It = TypeCache.find(Ty.getAsOpaquePtr());
3207  if (It != TypeCache.end()) {
3208    // Verify that the debug info still exists.
3209    if (llvm::Metadata *V = It->second)
3210      return cast<llvm::DIType>(V);
3211  }
3212
3213  return nullptr;
3214}
3215
3216void CGDebugInfo::completeTemplateDefinition(
3217    const ClassTemplateSpecializationDecl &SD) {
3218  completeUnusedClass(SD);
3219}
3220
3221void CGDebugInfo::completeUnusedClass(const CXXRecordDecl &D) {
3222  if (DebugKind <= codegenoptions::DebugLineTablesOnly)
3223    return;
3224
3225  completeClassData(&D);
3226  // In case this type has no member function definitions being emitted, ensure
3227  // it is retained
3228  RetainedTypes.push_back(CGM.getContext().getRecordType(&D).getAsOpaquePtr());
3229}
3230
3231llvm::DIType *CGDebugInfo::getOrCreateType(QualType Ty, llvm::DIFile *Unit) {
3232  if (Ty.isNull())
3233    return nullptr;
3234
3235  llvm::TimeTraceScope TimeScope("DebugType", [&]() {
3236    std::string Name;
3237    llvm::raw_string_ostream OS(Name);
3238    Ty.print(OS, getPrintingPolicy());
3239    return Name;
3240  });
3241
3242  // Unwrap the type as needed for debug information.
3243  Ty = UnwrapTypeForDebugInfo(Ty, CGM.getContext());
3244
3245  if (auto *T = getTypeOrNull(Ty))
3246    return T;
3247
3248  llvm::DIType *Res = CreateTypeNode(Ty, Unit);
3249  void *TyPtr = Ty.getAsOpaquePtr();
3250
3251  // And update the type cache.
3252  TypeCache[TyPtr].reset(Res);
3253
3254  return Res;
3255}
3256
3257llvm::DIModule *CGDebugInfo::getParentModuleOrNull(const Decl *D) {
3258  // A forward declaration inside a module header does not belong to the module.
3259  if (isa<RecordDecl>(D) && !cast<RecordDecl>(D)->getDefinition())
3260    return nullptr;
3261  if (DebugTypeExtRefs && D->isFromASTFile()) {
3262    // Record a reference to an imported clang module or precompiled header.
3263    auto *Reader = CGM.getContext().getExternalSource();
3264    auto Idx = D->getOwningModuleID();
3265    auto Info = Reader->getSourceDescriptor(Idx);
3266    if (Info)
3267      return getOrCreateModuleRef(*Info, /*SkeletonCU=*/true);
3268  } else if (ClangModuleMap) {
3269    // We are building a clang module or a precompiled header.
3270    //
3271    // TODO: When D is a CXXRecordDecl or a C++ Enum, the ODR applies
3272    // and it wouldn't be necessary to specify the parent scope
3273    // because the type is already unique by definition (it would look
3274    // like the output of -fno-standalone-debug). On the other hand,
3275    // the parent scope helps a consumer to quickly locate the object
3276    // file where the type's definition is located, so it might be
3277    // best to make this behavior a command line or debugger tuning
3278    // option.
3279    if (Module *M = D->getOwningModule()) {
3280      // This is a (sub-)module.
3281      auto Info = ASTSourceDescriptor(*M);
3282      return getOrCreateModuleRef(Info, /*SkeletonCU=*/false);
3283    } else {
3284      // This the precompiled header being built.
3285      return getOrCreateModuleRef(PCHDescriptor, /*SkeletonCU=*/false);
3286    }
3287  }
3288
3289  return nullptr;
3290}
3291
3292llvm::DIType *CGDebugInfo::CreateTypeNode(QualType Ty, llvm::DIFile *Unit) {
3293  // Handle qualifiers, which recursively handles what they refer to.
3294  if (Ty.hasLocalQualifiers())
3295    return CreateQualifiedType(Ty, Unit);
3296
3297  // Work out details of type.
3298  switch (Ty->getTypeClass()) {
3299#define TYPE(Class, Base)
3300#define ABSTRACT_TYPE(Class, Base)
3301#define NON_CANONICAL_TYPE(Class, Base)
3302#define DEPENDENT_TYPE(Class, Base) case Type::Class:
3303#include "clang/AST/TypeNodes.inc"
3304    llvm_unreachable("Dependent types cannot show up in debug information");
3305
3306  case Type::ExtVector:
3307  case Type::Vector:
3308    return CreateType(cast<VectorType>(Ty), Unit);
3309  case Type::ConstantMatrix:
3310    return CreateType(cast<ConstantMatrixType>(Ty), Unit);
3311  case Type::ObjCObjectPointer:
3312    return CreateType(cast<ObjCObjectPointerType>(Ty), Unit);
3313  case Type::ObjCObject:
3314    return CreateType(cast<ObjCObjectType>(Ty), Unit);
3315  case Type::ObjCTypeParam:
3316    return CreateType(cast<ObjCTypeParamType>(Ty), Unit);
3317  case Type::ObjCInterface:
3318    return CreateType(cast<ObjCInterfaceType>(Ty), Unit);
3319  case Type::Builtin:
3320    return CreateType(cast<BuiltinType>(Ty));
3321  case Type::Complex:
3322    return CreateType(cast<ComplexType>(Ty));
3323  case Type::Pointer:
3324    return CreateType(cast<PointerType>(Ty), Unit);
3325  case Type::BlockPointer:
3326    return CreateType(cast<BlockPointerType>(Ty), Unit);
3327  case Type::Typedef:
3328    return CreateType(cast<TypedefType>(Ty), Unit);
3329  case Type::Record:
3330    return CreateType(cast<RecordType>(Ty));
3331  case Type::Enum:
3332    return CreateEnumType(cast<EnumType>(Ty));
3333  case Type::FunctionProto:
3334  case Type::FunctionNoProto:
3335    return CreateType(cast<FunctionType>(Ty), Unit);
3336  case Type::ConstantArray:
3337  case Type::VariableArray:
3338  case Type::IncompleteArray:
3339    return CreateType(cast<ArrayType>(Ty), Unit);
3340
3341  case Type::LValueReference:
3342    return CreateType(cast<LValueReferenceType>(Ty), Unit);
3343  case Type::RValueReference:
3344    return CreateType(cast<RValueReferenceType>(Ty), Unit);
3345
3346  case Type::MemberPointer:
3347    return CreateType(cast<MemberPointerType>(Ty), Unit);
3348
3349  case Type::Atomic:
3350    return CreateType(cast<AtomicType>(Ty), Unit);
3351
3352  case Type::ExtInt:
3353    return CreateType(cast<ExtIntType>(Ty));
3354  case Type::Pipe:
3355    return CreateType(cast<PipeType>(Ty), Unit);
3356
3357  case Type::TemplateSpecialization:
3358    return CreateType(cast<TemplateSpecializationType>(Ty), Unit);
3359
3360  case Type::Auto:
3361  case Type::Attributed:
3362  case Type::Adjusted:
3363  case Type::Decayed:
3364  case Type::DeducedTemplateSpecialization:
3365  case Type::Elaborated:
3366  case Type::Paren:
3367  case Type::MacroQualified:
3368  case Type::SubstTemplateTypeParm:
3369  case Type::TypeOfExpr:
3370  case Type::TypeOf:
3371  case Type::Decltype:
3372  case Type::UnaryTransform:
3373    break;
3374  }
3375
3376  llvm_unreachable("type should have been unwrapped!");
3377}
3378
3379llvm::DICompositeType *
3380CGDebugInfo::getOrCreateLimitedType(const RecordType *Ty) {
3381  QualType QTy(Ty, 0);
3382
3383  auto *T = cast_or_null<llvm::DICompositeType>(getTypeOrNull(QTy));
3384
3385  // We may have cached a forward decl when we could have created
3386  // a non-forward decl. Go ahead and create a non-forward decl
3387  // now.
3388  if (T && !T->isForwardDecl())
3389    return T;
3390
3391  // Otherwise create the type.
3392  llvm::DICompositeType *Res = CreateLimitedType(Ty);
3393
3394  // Propagate members from the declaration to the definition
3395  // CreateType(const RecordType*) will overwrite this with the members in the
3396  // correct order if the full type is needed.
3397  DBuilder.replaceArrays(Res, T ? T->getElements() : llvm::DINodeArray());
3398
3399  // And update the type cache.
3400  TypeCache[QTy.getAsOpaquePtr()].reset(Res);
3401  return Res;
3402}
3403
3404// TODO: Currently used for context chains when limiting debug info.
3405llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
3406  RecordDecl *RD = Ty->getDecl();
3407
3408  // Get overall information about the record type for the debug info.
3409  StringRef RDName = getClassName(RD);
3410  const SourceLocation Loc = RD->getLocation();
3411  llvm::DIFile *DefUnit = nullptr;
3412  unsigned Line = 0;
3413  if (Loc.isValid()) {
3414    DefUnit = getOrCreateFile(Loc);
3415    Line = getLineNumber(Loc);
3416  }
3417
3418  llvm::DIScope *RDContext = getDeclContextDescriptor(RD);
3419
3420  // If we ended up creating the type during the context chain construction,
3421  // just return that.
3422  auto *T = cast_or_null<llvm::DICompositeType>(
3423      getTypeOrNull(CGM.getContext().getRecordType(RD)));
3424  if (T && (!T->isForwardDecl() || !RD->getDefinition()))
3425    return T;
3426
3427  // If this is just a forward or incomplete declaration, construct an
3428  // appropriately marked node and just return it.
3429  const RecordDecl *D = RD->getDefinition();
3430  if (!D || !D->isCompleteDefinition())
3431    return getOrCreateRecordFwdDecl(Ty, RDContext);
3432
3433  uint64_t Size = CGM.getContext().getTypeSize(Ty);
3434  auto Align = getDeclAlignIfRequired(D, CGM.getContext());
3435
3436  SmallString<256> Identifier = getTypeIdentifier(Ty, CGM, TheCU);
3437
3438  // Explicitly record the calling convention and export symbols for C++
3439  // records.
3440  auto Flags = llvm::DINode::FlagZero;
3441  if (auto CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
3442    if (CGM.getCXXABI().getRecordArgABI(CXXRD) == CGCXXABI::RAA_Indirect)
3443      Flags |= llvm::DINode::FlagTypePassByReference;
3444    else
3445      Flags |= llvm::DINode::FlagTypePassByValue;
3446
3447    // Record if a C++ record is non-trivial type.
3448    if (!CXXRD->isTrivial())
3449      Flags |= llvm::DINode::FlagNonTrivial;
3450
3451    // Record exports it symbols to the containing structure.
3452    if (CXXRD->isAnonymousStructOrUnion())
3453        Flags |= llvm::DINode::FlagExportSymbols;
3454  }
3455
3456  llvm::DICompositeType *RealDecl = DBuilder.createReplaceableCompositeType(
3457      getTagForRecord(RD), RDName, RDContext, DefUnit, Line, 0, Size, Align,
3458      Flags, Identifier);
3459
3460  // Elements of composite types usually have back to the type, creating
3461  // uniquing cycles.  Distinct nodes are more efficient.
3462  switch (RealDecl->getTag()) {
3463  default:
3464    llvm_unreachable("invalid composite type tag");
3465
3466  case llvm::dwarf::DW_TAG_array_type:
3467  case llvm::dwarf::DW_TAG_enumeration_type:
3468    // Array elements and most enumeration elements don't have back references,
3469    // so they don't tend to be involved in uniquing cycles and there is some
3470    // chance of merging them when linking together two modules.  Only make
3471    // them distinct if they are ODR-uniqued.
3472    if (Identifier.empty())
3473      break;
3474    LLVM_FALLTHROUGH;
3475
3476  case llvm::dwarf::DW_TAG_structure_type:
3477  case llvm::dwarf::DW_TAG_union_type:
3478  case llvm::dwarf::DW_TAG_class_type:
3479    // Immediately resolve to a distinct node.
3480    RealDecl =
3481        llvm::MDNode::replaceWithDistinct(llvm::TempDICompositeType(RealDecl));
3482    break;
3483  }
3484
3485  RegionMap[Ty->getDecl()].reset(RealDecl);
3486  TypeCache[QualType(Ty, 0).getAsOpaquePtr()].reset(RealDecl);
3487
3488  if (const auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
3489    DBuilder.replaceArrays(RealDecl, llvm::DINodeArray(),
3490                           CollectCXXTemplateParams(TSpecial, DefUnit));
3491  return RealDecl;
3492}
3493
3494void CGDebugInfo::CollectContainingType(const CXXRecordDecl *RD,
3495                                        llvm::DICompositeType *RealDecl) {
3496  // A class's primary base or the class itself contains the vtable.
3497  llvm::DICompositeType *ContainingType = nullptr;
3498  const ASTRecordLayout &RL = CGM.getContext().getASTRecordLayout(RD);
3499  if (const CXXRecordDecl *PBase = RL.getPrimaryBase()) {
3500    // Seek non-virtual primary base root.
3501    while (1) {
3502      const ASTRecordLayout &BRL = CGM.getContext().getASTRecordLayout(PBase);
3503      const CXXRecordDecl *PBT = BRL.getPrimaryBase();
3504      if (PBT && !BRL.isPrimaryBaseVirtual())
3505        PBase = PBT;
3506      else
3507        break;
3508    }
3509    ContainingType = cast<llvm::DICompositeType>(
3510        getOrCreateType(QualType(PBase->getTypeForDecl(), 0),
3511                        getOrCreateFile(RD->getLocation())));
3512  } else if (RD->isDynamicClass())
3513    ContainingType = RealDecl;
3514
3515  DBuilder.replaceVTableHolder(RealDecl, ContainingType);
3516}
3517
3518llvm::DIType *CGDebugInfo::CreateMemberType(llvm::DIFile *Unit, QualType FType,
3519                                            StringRef Name, uint64_t *Offset) {
3520  llvm::DIType *FieldTy = CGDebugInfo::getOrCreateType(FType, Unit);
3521  uint64_t FieldSize = CGM.getContext().getTypeSize(FType);
3522  auto FieldAlign = getTypeAlignIfRequired(FType, CGM.getContext());
3523  llvm::DIType *Ty =
3524      DBuilder.createMemberType(Unit, Name, Unit, 0, FieldSize, FieldAlign,
3525                                *Offset, llvm::DINode::FlagZero, FieldTy);
3526  *Offset += FieldSize;
3527  return Ty;
3528}
3529
3530void CGDebugInfo::collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
3531                                           StringRef &Name,
3532                                           StringRef &LinkageName,
3533                                           llvm::DIScope *&FDContext,
3534                                           llvm::DINodeArray &TParamsArray,
3535                                           llvm::DINode::DIFlags &Flags) {
3536  const auto *FD = cast<FunctionDecl>(GD.getCanonicalDecl().getDecl());
3537  Name = getFunctionName(FD);
3538  // Use mangled name as linkage name for C/C++ functions.
3539  if (FD->hasPrototype()) {
3540    LinkageName = CGM.getMangledName(GD);
3541    Flags |= llvm::DINode::FlagPrototyped;
3542  }
3543  // No need to replicate the linkage name if it isn't different from the
3544  // subprogram name, no need to have it at all unless coverage is enabled or
3545  // debug is set to more than just line tables or extra debug info is needed.
3546  if (LinkageName == Name || (!CGM.getCodeGenOpts().EmitGcovArcs &&
3547                              !CGM.getCodeGenOpts().EmitGcovNotes &&
3548                              !CGM.getCodeGenOpts().DebugInfoForProfiling &&
3549                              DebugKind <= codegenoptions::DebugLineTablesOnly))
3550    LinkageName = StringRef();
3551
3552  // Emit the function scope in line tables only mode (if CodeView) to
3553  // differentiate between function names.
3554  if (CGM.getCodeGenOpts().hasReducedDebugInfo() ||
3555      (DebugKind == codegenoptions::DebugLineTablesOnly &&
3556       CGM.getCodeGenOpts().EmitCodeView)) {
3557    if (const NamespaceDecl *NSDecl =
3558            dyn_cast_or_null<NamespaceDecl>(FD->getDeclContext()))
3559      FDContext = getOrCreateNamespace(NSDecl);
3560    else if (const RecordDecl *RDecl =
3561                 dyn_cast_or_null<RecordDecl>(FD->getDeclContext())) {
3562      llvm::DIScope *Mod = getParentModuleOrNull(RDecl);
3563      FDContext = getContextDescriptor(RDecl, Mod ? Mod : TheCU);
3564    }
3565  }
3566  if (CGM.getCodeGenOpts().hasReducedDebugInfo()) {
3567    // Check if it is a noreturn-marked function
3568    if (FD->isNoReturn())
3569      Flags |= llvm::DINode::FlagNoReturn;
3570    // Collect template parameters.
3571    TParamsArray = CollectFunctionTemplateParams(FD, Unit);
3572  }
3573}
3574
3575void CGDebugInfo::collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
3576                                      unsigned &LineNo, QualType &T,
3577                                      StringRef &Name, StringRef &LinkageName,
3578                                      llvm::MDTuple *&TemplateParameters,
3579                                      llvm::DIScope *&VDContext) {
3580  Unit = getOrCreateFile(VD->getLocation());
3581  LineNo = getLineNumber(VD->getLocation());
3582
3583  setLocation(VD->getLocation());
3584
3585  T = VD->getType();
3586  if (T->isIncompleteArrayType()) {
3587    // CodeGen turns int[] into int[1] so we'll do the same here.
3588    llvm::APInt ConstVal(32, 1);
3589    QualType ET = CGM.getContext().getAsArrayType(T)->getElementType();
3590
3591    T = CGM.getContext().getConstantArrayType(ET, ConstVal, nullptr,
3592                                              ArrayType::Normal, 0);
3593  }
3594
3595  Name = VD->getName();
3596  if (VD->getDeclContext() && !isa<FunctionDecl>(VD->getDeclContext()) &&
3597      !isa<ObjCMethodDecl>(VD->getDeclContext()))
3598    LinkageName = CGM.getMangledName(VD);
3599  if (LinkageName == Name)
3600    LinkageName = StringRef();
3601
3602  if (isa<VarTemplateSpecializationDecl>(VD)) {
3603    llvm::DINodeArray parameterNodes = CollectVarTemplateParams(VD, &*Unit);
3604    TemplateParameters = parameterNodes.get();
3605  } else {
3606    TemplateParameters = nullptr;
3607  }
3608
3609  // Since we emit declarations (DW_AT_members) for static members, place the
3610  // definition of those static members in the namespace they were declared in
3611  // in the source code (the lexical decl context).
3612  // FIXME: Generalize this for even non-member global variables where the
3613  // declaration and definition may have different lexical decl contexts, once
3614  // we have support for emitting declarations of (non-member) global variables.
3615  const DeclContext *DC = VD->isStaticDataMember() ? VD->getLexicalDeclContext()
3616                                                   : VD->getDeclContext();
3617  // When a record type contains an in-line initialization of a static data
3618  // member, and the record type is marked as __declspec(dllexport), an implicit
3619  // definition of the member will be created in the record context.  DWARF
3620  // doesn't seem to have a nice way to describe this in a form that consumers
3621  // are likely to understand, so fake the "normal" situation of a definition
3622  // outside the class by putting it in the global scope.
3623  if (DC->isRecord())
3624    DC = CGM.getContext().getTranslationUnitDecl();
3625
3626  llvm::DIScope *Mod = getParentModuleOrNull(VD);
3627  VDContext = getContextDescriptor(cast<Decl>(DC), Mod ? Mod : TheCU);
3628}
3629
3630llvm::DISubprogram *CGDebugInfo::getFunctionFwdDeclOrStub(GlobalDecl GD,
3631                                                          bool Stub) {
3632  llvm::DINodeArray TParamsArray;
3633  StringRef Name, LinkageName;
3634  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
3635  llvm::DISubprogram::DISPFlags SPFlags = llvm::DISubprogram::SPFlagZero;
3636  SourceLocation Loc = GD.getDecl()->getLocation();
3637  llvm::DIFile *Unit = getOrCreateFile(Loc);
3638  llvm::DIScope *DContext = Unit;
3639  unsigned Line = getLineNumber(Loc);
3640  collectFunctionDeclProps(GD, Unit, Name, LinkageName, DContext, TParamsArray,
3641                           Flags);
3642  auto *FD = cast<FunctionDecl>(GD.getDecl());
3643
3644  // Build function type.
3645  SmallVector<QualType, 16> ArgTypes;
3646  for (const ParmVarDecl *Parm : FD->parameters())
3647    ArgTypes.push_back(Parm->getType());
3648
3649  CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
3650  QualType FnType = CGM.getContext().getFunctionType(
3651      FD->getReturnType(), ArgTypes, FunctionProtoType::ExtProtoInfo(CC));
3652  if (!FD->isExternallyVisible())
3653    SPFlags |= llvm::DISubprogram::SPFlagLocalToUnit;
3654  if (CGM.getLangOpts().Optimize)
3655    SPFlags |= llvm::DISubprogram::SPFlagOptimized;
3656
3657  if (Stub) {
3658    Flags |= getCallSiteRelatedAttrs();
3659    SPFlags |= llvm::DISubprogram::SPFlagDefinition;
3660    return DBuilder.createFunction(
3661        DContext, Name, LinkageName, Unit, Line,
3662        getOrCreateFunctionType(GD.getDecl(), FnType, Unit), 0, Flags, SPFlags,
3663        TParamsArray.get(), getFunctionDeclaration(FD));
3664  }
3665
3666  llvm::DISubprogram *SP = DBuilder.createTempFunctionFwdDecl(
3667      DContext, Name, LinkageName, Unit, Line,
3668      getOrCreateFunctionType(GD.getDecl(), FnType, Unit), 0, Flags, SPFlags,
3669      TParamsArray.get(), getFunctionDeclaration(FD));
3670  const FunctionDecl *CanonDecl = FD->getCanonicalDecl();
3671  FwdDeclReplaceMap.emplace_back(std::piecewise_construct,
3672                                 std::make_tuple(CanonDecl),
3673                                 std::make_tuple(SP));
3674  return SP;
3675}
3676
3677llvm::DISubprogram *CGDebugInfo::getFunctionForwardDeclaration(GlobalDecl GD) {
3678  return getFunctionFwdDeclOrStub(GD, /* Stub = */ false);
3679}
3680
3681llvm::DISubprogram *CGDebugInfo::getFunctionStub(GlobalDecl GD) {
3682  return getFunctionFwdDeclOrStub(GD, /* Stub = */ true);
3683}
3684
3685llvm::DIGlobalVariable *
3686CGDebugInfo::getGlobalVariableForwardDeclaration(const VarDecl *VD) {
3687  QualType T;
3688  StringRef Name, LinkageName;
3689  SourceLocation Loc = VD->getLocation();
3690  llvm::DIFile *Unit = getOrCreateFile(Loc);
3691  llvm::DIScope *DContext = Unit;
3692  unsigned Line = getLineNumber(Loc);
3693  llvm::MDTuple *TemplateParameters = nullptr;
3694
3695  collectVarDeclProps(VD, Unit, Line, T, Name, LinkageName, TemplateParameters,
3696                      DContext);
3697  auto Align = getDeclAlignIfRequired(VD, CGM.getContext());
3698  auto *GV = DBuilder.createTempGlobalVariableFwdDecl(
3699      DContext, Name, LinkageName, Unit, Line, getOrCreateType(T, Unit),
3700      !VD->isExternallyVisible(), nullptr, TemplateParameters, Align);
3701  FwdDeclReplaceMap.emplace_back(
3702      std::piecewise_construct,
3703      std::make_tuple(cast<VarDecl>(VD->getCanonicalDecl())),
3704      std::make_tuple(static_cast<llvm::Metadata *>(GV)));
3705  return GV;
3706}
3707
3708llvm::DINode *CGDebugInfo::getDeclarationOrDefinition(const Decl *D) {
3709  // We only need a declaration (not a definition) of the type - so use whatever
3710  // we would otherwise do to get a type for a pointee. (forward declarations in
3711  // limited debug info, full definitions (if the type definition is available)
3712  // in unlimited debug info)
3713  if (const auto *TD = dyn_cast<TypeDecl>(D))
3714    return getOrCreateType(CGM.getContext().getTypeDeclType(TD),
3715                           getOrCreateFile(TD->getLocation()));
3716  auto I = DeclCache.find(D->getCanonicalDecl());
3717
3718  if (I != DeclCache.end()) {
3719    auto N = I->second;
3720    if (auto *GVE = dyn_cast_or_null<llvm::DIGlobalVariableExpression>(N))
3721      return GVE->getVariable();
3722    return dyn_cast_or_null<llvm::DINode>(N);
3723  }
3724
3725  // No definition for now. Emit a forward definition that might be
3726  // merged with a potential upcoming definition.
3727  if (const auto *FD = dyn_cast<FunctionDecl>(D))
3728    return getFunctionForwardDeclaration(FD);
3729  else if (const auto *VD = dyn_cast<VarDecl>(D))
3730    return getGlobalVariableForwardDeclaration(VD);
3731
3732  return nullptr;
3733}
3734
3735llvm::DISubprogram *CGDebugInfo::getFunctionDeclaration(const Decl *D) {
3736  if (!D || DebugKind <= codegenoptions::DebugLineTablesOnly)
3737    return nullptr;
3738
3739  const auto *FD = dyn_cast<FunctionDecl>(D);
3740  if (!FD)
3741    return nullptr;
3742
3743  // Setup context.
3744  auto *S = getDeclContextDescriptor(D);
3745
3746  auto MI = SPCache.find(FD->getCanonicalDecl());
3747  if (MI == SPCache.end()) {
3748    if (const auto *MD = dyn_cast<CXXMethodDecl>(FD->getCanonicalDecl())) {
3749      return CreateCXXMemberFunction(MD, getOrCreateFile(MD->getLocation()),
3750                                     cast<llvm::DICompositeType>(S));
3751    }
3752  }
3753  if (MI != SPCache.end()) {
3754    auto *SP = dyn_cast_or_null<llvm::DISubprogram>(MI->second);
3755    if (SP && !SP->isDefinition())
3756      return SP;
3757  }
3758
3759  for (auto NextFD : FD->redecls()) {
3760    auto MI = SPCache.find(NextFD->getCanonicalDecl());
3761    if (MI != SPCache.end()) {
3762      auto *SP = dyn_cast_or_null<llvm::DISubprogram>(MI->second);
3763      if (SP && !SP->isDefinition())
3764        return SP;
3765    }
3766  }
3767  return nullptr;
3768}
3769
3770llvm::DISubprogram *CGDebugInfo::getObjCMethodDeclaration(
3771    const Decl *D, llvm::DISubroutineType *FnType, unsigned LineNo,
3772    llvm::DINode::DIFlags Flags, llvm::DISubprogram::DISPFlags SPFlags) {
3773  if (!D || DebugKind <= codegenoptions::DebugLineTablesOnly)
3774    return nullptr;
3775
3776  const auto *OMD = dyn_cast<ObjCMethodDecl>(D);
3777  if (!OMD)
3778    return nullptr;
3779
3780  if (CGM.getCodeGenOpts().DwarfVersion < 5 && !OMD->isDirectMethod())
3781    return nullptr;
3782
3783  if (OMD->isDirectMethod())
3784    SPFlags |= llvm::DISubprogram::SPFlagObjCDirect;
3785
3786  // Starting with DWARF V5 method declarations are emitted as children of
3787  // the interface type.
3788  auto *ID = dyn_cast_or_null<ObjCInterfaceDecl>(D->getDeclContext());
3789  if (!ID)
3790    ID = OMD->getClassInterface();
3791  if (!ID)
3792    return nullptr;
3793  QualType QTy(ID->getTypeForDecl(), 0);
3794  auto It = TypeCache.find(QTy.getAsOpaquePtr());
3795  if (It == TypeCache.end())
3796    return nullptr;
3797  auto *InterfaceType = cast<llvm::DICompositeType>(It->second);
3798  llvm::DISubprogram *FD = DBuilder.createFunction(
3799      InterfaceType, getObjCMethodName(OMD), StringRef(),
3800      InterfaceType->getFile(), LineNo, FnType, LineNo, Flags, SPFlags);
3801  DBuilder.finalizeSubprogram(FD);
3802  ObjCMethodCache[ID].push_back({FD, OMD->isDirectMethod()});
3803  return FD;
3804}
3805
3806// getOrCreateFunctionType - Construct type. If it is a c++ method, include
3807// implicit parameter "this".
3808llvm::DISubroutineType *CGDebugInfo::getOrCreateFunctionType(const Decl *D,
3809                                                             QualType FnType,
3810                                                             llvm::DIFile *F) {
3811  // In CodeView, we emit the function types in line tables only because the
3812  // only way to distinguish between functions is by display name and type.
3813  if (!D || (DebugKind <= codegenoptions::DebugLineTablesOnly &&
3814             !CGM.getCodeGenOpts().EmitCodeView))
3815    // Create fake but valid subroutine type. Otherwise -verify would fail, and
3816    // subprogram DIE will miss DW_AT_decl_file and DW_AT_decl_line fields.
3817    return DBuilder.createSubroutineType(DBuilder.getOrCreateTypeArray(None));
3818
3819  if (const auto *Method = dyn_cast<CXXMethodDecl>(D))
3820    return getOrCreateMethodType(Method, F, false);
3821
3822  const auto *FTy = FnType->getAs<FunctionType>();
3823  CallingConv CC = FTy ? FTy->getCallConv() : CallingConv::CC_C;
3824
3825  if (const auto *OMethod = dyn_cast<ObjCMethodDecl>(D)) {
3826    // Add "self" and "_cmd"
3827    SmallVector<llvm::Metadata *, 16> Elts;
3828
3829    // First element is always return type. For 'void' functions it is NULL.
3830    QualType ResultTy = OMethod->getReturnType();
3831
3832    // Replace the instancetype keyword with the actual type.
3833    if (ResultTy == CGM.getContext().getObjCInstanceType())
3834      ResultTy = CGM.getContext().getPointerType(
3835          QualType(OMethod->getClassInterface()->getTypeForDecl(), 0));
3836
3837    Elts.push_back(getOrCreateType(ResultTy, F));
3838    // "self" pointer is always first argument.
3839    QualType SelfDeclTy;
3840    if (auto *SelfDecl = OMethod->getSelfDecl())
3841      SelfDeclTy = SelfDecl->getType();
3842    else if (auto *FPT = dyn_cast<FunctionProtoType>(FnType))
3843      if (FPT->getNumParams() > 1)
3844        SelfDeclTy = FPT->getParamType(0);
3845    if (!SelfDeclTy.isNull())
3846      Elts.push_back(
3847          CreateSelfType(SelfDeclTy, getOrCreateType(SelfDeclTy, F)));
3848    // "_cmd" pointer is always second argument.
3849    Elts.push_back(DBuilder.createArtificialType(
3850        getOrCreateType(CGM.getContext().getObjCSelType(), F)));
3851    // Get rest of the arguments.
3852    for (const auto *PI : OMethod->parameters())
3853      Elts.push_back(getOrCreateType(PI->getType(), F));
3854    // Variadic methods need a special marker at the end of the type list.
3855    if (OMethod->isVariadic())
3856      Elts.push_back(DBuilder.createUnspecifiedParameter());
3857
3858    llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(Elts);
3859    return DBuilder.createSubroutineType(EltTypeArray, llvm::DINode::FlagZero,
3860                                         getDwarfCC(CC));
3861  }
3862
3863  // Handle variadic function types; they need an additional
3864  // unspecified parameter.
3865  if (const auto *FD = dyn_cast<FunctionDecl>(D))
3866    if (FD->isVariadic()) {
3867      SmallVector<llvm::Metadata *, 16> EltTys;
3868      EltTys.push_back(getOrCreateType(FD->getReturnType(), F));
3869      if (const auto *FPT = dyn_cast<FunctionProtoType>(FnType))
3870        for (QualType ParamType : FPT->param_types())
3871          EltTys.push_back(getOrCreateType(ParamType, F));
3872      EltTys.push_back(DBuilder.createUnspecifiedParameter());
3873      llvm::DITypeRefArray EltTypeArray = DBuilder.getOrCreateTypeArray(EltTys);
3874      return DBuilder.createSubroutineType(EltTypeArray, llvm::DINode::FlagZero,
3875                                           getDwarfCC(CC));
3876    }
3877
3878  return cast<llvm::DISubroutineType>(getOrCreateType(FnType, F));
3879}
3880
3881void CGDebugInfo::emitFunctionStart(GlobalDecl GD, SourceLocation Loc,
3882                                    SourceLocation ScopeLoc, QualType FnType,
3883                                    llvm::Function *Fn, bool CurFuncIsThunk) {
3884  StringRef Name;
3885  StringRef LinkageName;
3886
3887  FnBeginRegionCount.push_back(LexicalBlockStack.size());
3888
3889  const Decl *D = GD.getDecl();
3890  bool HasDecl = (D != nullptr);
3891
3892  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
3893  llvm::DISubprogram::DISPFlags SPFlags = llvm::DISubprogram::SPFlagZero;
3894  llvm::DIFile *Unit = getOrCreateFile(Loc);
3895  llvm::DIScope *FDContext = Unit;
3896  llvm::DINodeArray TParamsArray;
3897  if (!HasDecl) {
3898    // Use llvm function name.
3899    LinkageName = Fn->getName();
3900  } else if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
3901    // If there is a subprogram for this function available then use it.
3902    auto FI = SPCache.find(FD->getCanonicalDecl());
3903    if (FI != SPCache.end()) {
3904      auto *SP = dyn_cast_or_null<llvm::DISubprogram>(FI->second);
3905      if (SP && SP->isDefinition()) {
3906        LexicalBlockStack.emplace_back(SP);
3907        RegionMap[D].reset(SP);
3908        return;
3909      }
3910    }
3911    collectFunctionDeclProps(GD, Unit, Name, LinkageName, FDContext,
3912                             TParamsArray, Flags);
3913  } else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(D)) {
3914    Name = getObjCMethodName(OMD);
3915    Flags |= llvm::DINode::FlagPrototyped;
3916  } else if (isa<VarDecl>(D) &&
3917             GD.getDynamicInitKind() != DynamicInitKind::NoStub) {
3918    // This is a global initializer or atexit destructor for a global variable.
3919    Name = getDynamicInitializerName(cast<VarDecl>(D), GD.getDynamicInitKind(),
3920                                     Fn);
3921  } else {
3922    Name = Fn->getName();
3923
3924    if (isa<BlockDecl>(D))
3925      LinkageName = Name;
3926
3927    Flags |= llvm::DINode::FlagPrototyped;
3928  }
3929  if (Name.startswith("\01"))
3930    Name = Name.substr(1);
3931
3932  if (!HasDecl || D->isImplicit() || D->hasAttr<ArtificialAttr>() ||
3933      (isa<VarDecl>(D) && GD.getDynamicInitKind() != DynamicInitKind::NoStub)) {
3934    Flags |= llvm::DINode::FlagArtificial;
3935    // Artificial functions should not silently reuse CurLoc.
3936    CurLoc = SourceLocation();
3937  }
3938
3939  if (CurFuncIsThunk)
3940    Flags |= llvm::DINode::FlagThunk;
3941
3942  if (Fn->hasLocalLinkage())
3943    SPFlags |= llvm::DISubprogram::SPFlagLocalToUnit;
3944  if (CGM.getLangOpts().Optimize)
3945    SPFlags |= llvm::DISubprogram::SPFlagOptimized;
3946
3947  llvm::DINode::DIFlags FlagsForDef = Flags | getCallSiteRelatedAttrs();
3948  llvm::DISubprogram::DISPFlags SPFlagsForDef =
3949      SPFlags | llvm::DISubprogram::SPFlagDefinition;
3950
3951  const unsigned LineNo = getLineNumber(Loc.isValid() ? Loc : CurLoc);
3952  unsigned ScopeLine = getLineNumber(ScopeLoc);
3953  llvm::DISubroutineType *DIFnType = getOrCreateFunctionType(D, FnType, Unit);
3954  llvm::DISubprogram *Decl = nullptr;
3955  if (D)
3956    Decl = isa<ObjCMethodDecl>(D)
3957               ? getObjCMethodDeclaration(D, DIFnType, LineNo, Flags, SPFlags)
3958               : getFunctionDeclaration(D);
3959
3960  // FIXME: The function declaration we're constructing here is mostly reusing
3961  // declarations from CXXMethodDecl and not constructing new ones for arbitrary
3962  // FunctionDecls. When/if we fix this we can have FDContext be TheCU/null for
3963  // all subprograms instead of the actual context since subprogram definitions
3964  // are emitted as CU level entities by the backend.
3965  llvm::DISubprogram *SP = DBuilder.createFunction(
3966      FDContext, Name, LinkageName, Unit, LineNo, DIFnType, ScopeLine,
3967      FlagsForDef, SPFlagsForDef, TParamsArray.get(), Decl);
3968  Fn->setSubprogram(SP);
3969  // We might get here with a VarDecl in the case we're generating
3970  // code for the initialization of globals. Do not record these decls
3971  // as they will overwrite the actual VarDecl Decl in the cache.
3972  if (HasDecl && isa<FunctionDecl>(D))
3973    DeclCache[D->getCanonicalDecl()].reset(SP);
3974
3975  // Push the function onto the lexical block stack.
3976  LexicalBlockStack.emplace_back(SP);
3977
3978  if (HasDecl)
3979    RegionMap[D].reset(SP);
3980}
3981
3982void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
3983                                   QualType FnType, llvm::Function *Fn) {
3984  StringRef Name;
3985  StringRef LinkageName;
3986
3987  const Decl *D = GD.getDecl();
3988  if (!D)
3989    return;
3990
3991  llvm::TimeTraceScope TimeScope("DebugFunction", [&]() {
3992    std::string Name;
3993    llvm::raw_string_ostream OS(Name);
3994    if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
3995      ND->getNameForDiagnostic(OS, getPrintingPolicy(),
3996                               /*Qualified=*/true);
3997    return Name;
3998  });
3999
4000  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
4001  llvm::DIFile *Unit = getOrCreateFile(Loc);
4002  bool IsDeclForCallSite = Fn ? true : false;
4003  llvm::DIScope *FDContext =
4004      IsDeclForCallSite ? Unit : getDeclContextDescriptor(D);
4005  llvm::DINodeArray TParamsArray;
4006  if (isa<FunctionDecl>(D)) {
4007    // If there is a DISubprogram for this function available then use it.
4008    collectFunctionDeclProps(GD, Unit, Name, LinkageName, FDContext,
4009                             TParamsArray, Flags);
4010  } else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(D)) {
4011    Name = getObjCMethodName(OMD);
4012    Flags |= llvm::DINode::FlagPrototyped;
4013  } else {
4014    llvm_unreachable("not a function or ObjC method");
4015  }
4016  if (!Name.empty() && Name[0] == '\01')
4017    Name = Name.substr(1);
4018
4019  if (D->isImplicit()) {
4020    Flags |= llvm::DINode::FlagArtificial;
4021    // Artificial functions without a location should not silently reuse CurLoc.
4022    if (Loc.isInvalid())
4023      CurLoc = SourceLocation();
4024  }
4025  unsigned LineNo = getLineNumber(Loc);
4026  unsigned ScopeLine = 0;
4027  llvm::DISubprogram::DISPFlags SPFlags = llvm::DISubprogram::SPFlagZero;
4028  if (CGM.getLangOpts().Optimize)
4029    SPFlags |= llvm::DISubprogram::SPFlagOptimized;
4030
4031  llvm::DISubprogram *SP = DBuilder.createFunction(
4032      FDContext, Name, LinkageName, Unit, LineNo,
4033      getOrCreateFunctionType(D, FnType, Unit), ScopeLine, Flags, SPFlags,
4034      TParamsArray.get(), getFunctionDeclaration(D));
4035
4036  if (IsDeclForCallSite)
4037    Fn->setSubprogram(SP);
4038
4039  DBuilder.finalizeSubprogram(SP);
4040}
4041
4042void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
4043                                          QualType CalleeType,
4044                                          const FunctionDecl *CalleeDecl) {
4045  if (!CallOrInvoke)
4046    return;
4047  auto *Func = CallOrInvoke->getCalledFunction();
4048  if (!Func)
4049    return;
4050  if (Func->getSubprogram())
4051    return;
4052
4053  // Do not emit a declaration subprogram for a builtin, a function with nodebug
4054  // attribute, or if call site info isn't required. Also, elide declarations
4055  // for functions with reserved names, as call site-related features aren't
4056  // interesting in this case (& also, the compiler may emit calls to these
4057  // functions without debug locations, which makes the verifier complain).
4058  if (CalleeDecl->getBuiltinID() != 0 || CalleeDecl->hasAttr<NoDebugAttr>() ||
4059      getCallSiteRelatedAttrs() == llvm::DINode::FlagZero)
4060    return;
4061  if (CalleeDecl->isReserved(CGM.getLangOpts()) !=
4062      ReservedIdentifierStatus::NotReserved)
4063    return;
4064
4065  // If there is no DISubprogram attached to the function being called,
4066  // create the one describing the function in order to have complete
4067  // call site debug info.
4068  if (!CalleeDecl->isStatic() && !CalleeDecl->isInlined())
4069    EmitFunctionDecl(CalleeDecl, CalleeDecl->getLocation(), CalleeType, Func);
4070}
4071
4072void CGDebugInfo::EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD) {
4073  const auto *FD = cast<FunctionDecl>(GD.getDecl());
4074  // If there is a subprogram for this function available then use it.
4075  auto FI = SPCache.find(FD->getCanonicalDecl());
4076  llvm::DISubprogram *SP = nullptr;
4077  if (FI != SPCache.end())
4078    SP = dyn_cast_or_null<llvm::DISubprogram>(FI->second);
4079  if (!SP || !SP->isDefinition())
4080    SP = getFunctionStub(GD);
4081  FnBeginRegionCount.push_back(LexicalBlockStack.size());
4082  LexicalBlockStack.emplace_back(SP);
4083  setInlinedAt(Builder.getCurrentDebugLocation());
4084  EmitLocation(Builder, FD->getLocation());
4085}
4086
4087void CGDebugInfo::EmitInlineFunctionEnd(CGBuilderTy &Builder) {
4088  assert(CurInlinedAt && "unbalanced inline scope stack");
4089  EmitFunctionEnd(Builder, nullptr);
4090  setInlinedAt(llvm::DebugLoc(CurInlinedAt).getInlinedAt());
4091}
4092
4093void CGDebugInfo::EmitLocation(CGBuilderTy &Builder, SourceLocation Loc) {
4094  // Update our current location
4095  setLocation(Loc);
4096
4097  if (CurLoc.isInvalid() || CurLoc.isMacroID() || LexicalBlockStack.empty())
4098    return;
4099
4100  llvm::MDNode *Scope = LexicalBlockStack.back();
4101  Builder.SetCurrentDebugLocation(
4102      llvm::DILocation::get(CGM.getLLVMContext(), getLineNumber(CurLoc),
4103                            getColumnNumber(CurLoc), Scope, CurInlinedAt));
4104}
4105
4106void CGDebugInfo::CreateLexicalBlock(SourceLocation Loc) {
4107  llvm::MDNode *Back = nullptr;
4108  if (!LexicalBlockStack.empty())
4109    Back = LexicalBlockStack.back().get();
4110  LexicalBlockStack.emplace_back(DBuilder.createLexicalBlock(
4111      cast<llvm::DIScope>(Back), getOrCreateFile(CurLoc), getLineNumber(CurLoc),
4112      getColumnNumber(CurLoc)));
4113}
4114
4115void CGDebugInfo::AppendAddressSpaceXDeref(
4116    unsigned AddressSpace, SmallVectorImpl<int64_t> &Expr) const {
4117  Optional<unsigned> DWARFAddressSpace =
4118      CGM.getTarget().getDWARFAddressSpace(AddressSpace);
4119  if (!DWARFAddressSpace)
4120    return;
4121
4122  Expr.push_back(llvm::dwarf::DW_OP_constu);
4123  Expr.push_back(DWARFAddressSpace.getValue());
4124  Expr.push_back(llvm::dwarf::DW_OP_swap);
4125  Expr.push_back(llvm::dwarf::DW_OP_xderef);
4126}
4127
4128void CGDebugInfo::EmitLexicalBlockStart(CGBuilderTy &Builder,
4129                                        SourceLocation Loc) {
4130  // Set our current location.
4131  setLocation(Loc);
4132
4133  // Emit a line table change for the current location inside the new scope.
4134  Builder.SetCurrentDebugLocation(llvm::DILocation::get(
4135      CGM.getLLVMContext(), getLineNumber(Loc), getColumnNumber(Loc),
4136      LexicalBlockStack.back(), CurInlinedAt));
4137
4138  if (DebugKind <= codegenoptions::DebugLineTablesOnly)
4139    return;
4140
4141  // Create a new lexical block and push it on the stack.
4142  CreateLexicalBlock(Loc);
4143}
4144
4145void CGDebugInfo::EmitLexicalBlockEnd(CGBuilderTy &Builder,
4146                                      SourceLocation Loc) {
4147  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
4148
4149  // Provide an entry in the line table for the end of the block.
4150  EmitLocation(Builder, Loc);
4151
4152  if (DebugKind <= codegenoptions::DebugLineTablesOnly)
4153    return;
4154
4155  LexicalBlockStack.pop_back();
4156}
4157
4158void CGDebugInfo::EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn) {
4159  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
4160  unsigned RCount = FnBeginRegionCount.back();
4161  assert(RCount <= LexicalBlockStack.size() && "Region stack mismatch");
4162
4163  // Pop all regions for this function.
4164  while (LexicalBlockStack.size() != RCount) {
4165    // Provide an entry in the line table for the end of the block.
4166    EmitLocation(Builder, CurLoc);
4167    LexicalBlockStack.pop_back();
4168  }
4169  FnBeginRegionCount.pop_back();
4170
4171  if (Fn && Fn->getSubprogram())
4172    DBuilder.finalizeSubprogram(Fn->getSubprogram());
4173}
4174
4175CGDebugInfo::BlockByRefType
4176CGDebugInfo::EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
4177                                          uint64_t *XOffset) {
4178  SmallVector<llvm::Metadata *, 5> EltTys;
4179  QualType FType;
4180  uint64_t FieldSize, FieldOffset;
4181  uint32_t FieldAlign;
4182
4183  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
4184  QualType Type = VD->getType();
4185
4186  FieldOffset = 0;
4187  FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
4188  EltTys.push_back(CreateMemberType(Unit, FType, "__isa", &FieldOffset));
4189  EltTys.push_back(CreateMemberType(Unit, FType, "__forwarding", &FieldOffset));
4190  FType = CGM.getContext().IntTy;
4191  EltTys.push_back(CreateMemberType(Unit, FType, "__flags", &FieldOffset));
4192  EltTys.push_back(CreateMemberType(Unit, FType, "__size", &FieldOffset));
4193
4194  bool HasCopyAndDispose = CGM.getContext().BlockRequiresCopying(Type, VD);
4195  if (HasCopyAndDispose) {
4196    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
4197    EltTys.push_back(
4198        CreateMemberType(Unit, FType, "__copy_helper", &FieldOffset));
4199    EltTys.push_back(
4200        CreateMemberType(Unit, FType, "__destroy_helper", &FieldOffset));
4201  }
4202  bool HasByrefExtendedLayout;
4203  Qualifiers::ObjCLifetime Lifetime;
4204  if (CGM.getContext().getByrefLifetime(Type, Lifetime,
4205                                        HasByrefExtendedLayout) &&
4206      HasByrefExtendedLayout) {
4207    FType = CGM.getContext().getPointerType(CGM.getContext().VoidTy);
4208    EltTys.push_back(
4209        CreateMemberType(Unit, FType, "__byref_variable_layout", &FieldOffset));
4210  }
4211
4212  CharUnits Align = CGM.getContext().getDeclAlign(VD);
4213  if (Align > CGM.getContext().toCharUnitsFromBits(
4214                  CGM.getTarget().getPointerAlign(0))) {
4215    CharUnits FieldOffsetInBytes =
4216        CGM.getContext().toCharUnitsFromBits(FieldOffset);
4217    CharUnits AlignedOffsetInBytes = FieldOffsetInBytes.alignTo(Align);
4218    CharUnits NumPaddingBytes = AlignedOffsetInBytes - FieldOffsetInBytes;
4219
4220    if (NumPaddingBytes.isPositive()) {
4221      llvm::APInt pad(32, NumPaddingBytes.getQuantity());
4222      FType = CGM.getContext().getConstantArrayType(
4223          CGM.getContext().CharTy, pad, nullptr, ArrayType::Normal, 0);
4224      EltTys.push_back(CreateMemberType(Unit, FType, "", &FieldOffset));
4225    }
4226  }
4227
4228  FType = Type;
4229  llvm::DIType *WrappedTy = getOrCreateType(FType, Unit);
4230  FieldSize = CGM.getContext().getTypeSize(FType);
4231  FieldAlign = CGM.getContext().toBits(Align);
4232
4233  *XOffset = FieldOffset;
4234  llvm::DIType *FieldTy = DBuilder.createMemberType(
4235      Unit, VD->getName(), Unit, 0, FieldSize, FieldAlign, FieldOffset,
4236      llvm::DINode::FlagZero, WrappedTy);
4237  EltTys.push_back(FieldTy);
4238  FieldOffset += FieldSize;
4239
4240  llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
4241  return {DBuilder.createStructType(Unit, "", Unit, 0, FieldOffset, 0,
4242                                    llvm::DINode::FlagZero, nullptr, Elements),
4243          WrappedTy};
4244}
4245
4246llvm::DILocalVariable *CGDebugInfo::EmitDeclare(const VarDecl *VD,
4247                                                llvm::Value *Storage,
4248                                                llvm::Optional<unsigned> ArgNo,
4249                                                CGBuilderTy &Builder,
4250                                                const bool UsePointerValue) {
4251  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4252  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
4253  if (VD->hasAttr<NoDebugAttr>())
4254    return nullptr;
4255
4256  bool Unwritten =
4257      VD->isImplicit() || (isa<Decl>(VD->getDeclContext()) &&
4258                           cast<Decl>(VD->getDeclContext())->isImplicit());
4259  llvm::DIFile *Unit = nullptr;
4260  if (!Unwritten)
4261    Unit = getOrCreateFile(VD->getLocation());
4262  llvm::DIType *Ty;
4263  uint64_t XOffset = 0;
4264  if (VD->hasAttr<BlocksAttr>())
4265    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset).WrappedType;
4266  else
4267    Ty = getOrCreateType(VD->getType(), Unit);
4268
4269  // If there is no debug info for this type then do not emit debug info
4270  // for this variable.
4271  if (!Ty)
4272    return nullptr;
4273
4274  // Get location information.
4275  unsigned Line = 0;
4276  unsigned Column = 0;
4277  if (!Unwritten) {
4278    Line = getLineNumber(VD->getLocation());
4279    Column = getColumnNumber(VD->getLocation());
4280  }
4281  SmallVector<int64_t, 13> Expr;
4282  llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
4283  if (VD->isImplicit())
4284    Flags |= llvm::DINode::FlagArtificial;
4285
4286  auto Align = getDeclAlignIfRequired(VD, CGM.getContext());
4287
4288  unsigned AddressSpace = CGM.getContext().getTargetAddressSpace(VD->getType());
4289  AppendAddressSpaceXDeref(AddressSpace, Expr);
4290
4291  // If this is implicit parameter of CXXThis or ObjCSelf kind, then give it an
4292  // object pointer flag.
4293  if (const auto *IPD = dyn_cast<ImplicitParamDecl>(VD)) {
4294    if (IPD->getParameterKind() == ImplicitParamDecl::CXXThis ||
4295        IPD->getParameterKind() == ImplicitParamDecl::ObjCSelf)
4296      Flags |= llvm::DINode::FlagObjectPointer;
4297  }
4298
4299  // Note: Older versions of clang used to emit byval references with an extra
4300  // DW_OP_deref, because they referenced the IR arg directly instead of
4301  // referencing an alloca. Newer versions of LLVM don't treat allocas
4302  // differently from other function arguments when used in a dbg.declare.
4303  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
4304  StringRef Name = VD->getName();
4305  if (!Name.empty()) {
4306    // __block vars are stored on the heap if they are captured by a block that
4307    // can escape the local scope.
4308    if (VD->isEscapingByref()) {
4309      // Here, we need an offset *into* the alloca.
4310      CharUnits offset = CharUnits::fromQuantity(32);
4311      Expr.push_back(llvm::dwarf::DW_OP_plus_uconst);
4312      // offset of __forwarding field
4313      offset = CGM.getContext().toCharUnitsFromBits(
4314          CGM.getTarget().getPointerWidth(0));
4315      Expr.push_back(offset.getQuantity());
4316      Expr.push_back(llvm::dwarf::DW_OP_deref);
4317      Expr.push_back(llvm::dwarf::DW_OP_plus_uconst);
4318      // offset of x field
4319      offset = CGM.getContext().toCharUnitsFromBits(XOffset);
4320      Expr.push_back(offset.getQuantity());
4321    }
4322  } else if (const auto *RT = dyn_cast<RecordType>(VD->getType())) {
4323    // If VD is an anonymous union then Storage represents value for
4324    // all union fields.
4325    const RecordDecl *RD = RT->getDecl();
4326    if (RD->isUnion() && RD->isAnonymousStructOrUnion()) {
4327      // GDB has trouble finding local variables in anonymous unions, so we emit
4328      // artificial local variables for each of the members.
4329      //
4330      // FIXME: Remove this code as soon as GDB supports this.
4331      // The debug info verifier in LLVM operates based on the assumption that a
4332      // variable has the same size as its storage and we had to disable the
4333      // check for artificial variables.
4334      for (const auto *Field : RD->fields()) {
4335        llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
4336        StringRef FieldName = Field->getName();
4337
4338        // Ignore unnamed fields. Do not ignore unnamed records.
4339        if (FieldName.empty() && !isa<RecordType>(Field->getType()))
4340          continue;
4341
4342        // Use VarDecl's Tag, Scope and Line number.
4343        auto FieldAlign = getDeclAlignIfRequired(Field, CGM.getContext());
4344        auto *D = DBuilder.createAutoVariable(
4345            Scope, FieldName, Unit, Line, FieldTy, CGM.getLangOpts().Optimize,
4346            Flags | llvm::DINode::FlagArtificial, FieldAlign);
4347
4348        // Insert an llvm.dbg.declare into the current block.
4349        DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(Expr),
4350                               llvm::DILocation::get(CGM.getLLVMContext(), Line,
4351                                                     Column, Scope,
4352                                                     CurInlinedAt),
4353                               Builder.GetInsertBlock());
4354      }
4355    }
4356  }
4357
4358  // Clang stores the sret pointer provided by the caller in a static alloca.
4359  // Use DW_OP_deref to tell the debugger to load the pointer and treat it as
4360  // the address of the variable.
4361  if (UsePointerValue) {
4362    assert(std::find(Expr.begin(), Expr.end(), llvm::dwarf::DW_OP_deref) ==
4363               Expr.end() &&
4364           "Debug info already contains DW_OP_deref.");
4365    Expr.push_back(llvm::dwarf::DW_OP_deref);
4366  }
4367
4368  // Create the descriptor for the variable.
4369  llvm::DILocalVariable *D = nullptr;
4370  if (ArgNo) {
4371    D = DBuilder.createParameterVariable(Scope, Name, *ArgNo, Unit, Line, Ty,
4372                                         CGM.getLangOpts().Optimize, Flags);
4373  } else {
4374    // For normal local variable, we will try to find out whether 'VD' is the
4375    // copy parameter of coroutine.
4376    // If yes, we are going to use DIVariable of the origin parameter instead
4377    // of creating the new one.
4378    // If no, it might be a normal alloc, we just create a new one for it.
4379
4380    // Check whether the VD is move parameters.
4381    auto RemapCoroArgToLocalVar = [&]() -> llvm::DILocalVariable * {
4382      // The scope of parameter and move-parameter should be distinct
4383      // DISubprogram.
4384      if (!isa<llvm::DISubprogram>(Scope) || !Scope->isDistinct())
4385        return nullptr;
4386
4387      auto Iter = llvm::find_if(CoroutineParameterMappings, [&](auto &Pair) {
4388        Stmt *StmtPtr = const_cast<Stmt *>(Pair.second);
4389        if (DeclStmt *DeclStmtPtr = dyn_cast<DeclStmt>(StmtPtr)) {
4390          DeclGroupRef DeclGroup = DeclStmtPtr->getDeclGroup();
4391          Decl *Decl = DeclGroup.getSingleDecl();
4392          if (VD == dyn_cast_or_null<VarDecl>(Decl))
4393            return true;
4394        }
4395        return false;
4396      });
4397
4398      if (Iter != CoroutineParameterMappings.end()) {
4399        ParmVarDecl *PD = const_cast<ParmVarDecl *>(Iter->first);
4400        auto Iter2 = llvm::find_if(ParamDbgMappings, [&](auto &DbgPair) {
4401          return DbgPair.first == PD && DbgPair.second->getScope() == Scope;
4402        });
4403        if (Iter2 != ParamDbgMappings.end())
4404          return const_cast<llvm::DILocalVariable *>(Iter2->second);
4405      }
4406      return nullptr;
4407    };
4408
4409    // If we couldn't find a move param DIVariable, create a new one.
4410    D = RemapCoroArgToLocalVar();
4411    // Or we will create a new DIVariable for this Decl if D dose not exists.
4412    if (!D)
4413      D = DBuilder.createAutoVariable(Scope, Name, Unit, Line, Ty,
4414                                      CGM.getLangOpts().Optimize, Flags, Align);
4415  }
4416  // Insert an llvm.dbg.declare into the current block.
4417  DBuilder.insertDeclare(Storage, D, DBuilder.createExpression(Expr),
4418                         llvm::DILocation::get(CGM.getLLVMContext(), Line,
4419                                               Column, Scope, CurInlinedAt),
4420                         Builder.GetInsertBlock());
4421
4422  return D;
4423}
4424
4425llvm::DILocalVariable *
4426CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD, llvm::Value *Storage,
4427                                       CGBuilderTy &Builder,
4428                                       const bool UsePointerValue) {
4429  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4430  return EmitDeclare(VD, Storage, llvm::None, Builder, UsePointerValue);
4431}
4432
4433void CGDebugInfo::EmitLabel(const LabelDecl *D, CGBuilderTy &Builder) {
4434  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4435  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
4436
4437  if (D->hasAttr<NoDebugAttr>())
4438    return;
4439
4440  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
4441  llvm::DIFile *Unit = getOrCreateFile(D->getLocation());
4442
4443  // Get location information.
4444  unsigned Line = getLineNumber(D->getLocation());
4445  unsigned Column = getColumnNumber(D->getLocation());
4446
4447  StringRef Name = D->getName();
4448
4449  // Create the descriptor for the label.
4450  auto *L =
4451      DBuilder.createLabel(Scope, Name, Unit, Line, CGM.getLangOpts().Optimize);
4452
4453  // Insert an llvm.dbg.label into the current block.
4454  DBuilder.insertLabel(L,
4455                       llvm::DILocation::get(CGM.getLLVMContext(), Line, Column,
4456                                             Scope, CurInlinedAt),
4457                       Builder.GetInsertBlock());
4458}
4459
4460llvm::DIType *CGDebugInfo::CreateSelfType(const QualType &QualTy,
4461                                          llvm::DIType *Ty) {
4462  llvm::DIType *CachedTy = getTypeOrNull(QualTy);
4463  if (CachedTy)
4464    Ty = CachedTy;
4465  return DBuilder.createObjectPointerType(Ty);
4466}
4467
4468void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
4469    const VarDecl *VD, llvm::Value *Storage, CGBuilderTy &Builder,
4470    const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint) {
4471  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4472  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
4473
4474  if (Builder.GetInsertBlock() == nullptr)
4475    return;
4476  if (VD->hasAttr<NoDebugAttr>())
4477    return;
4478
4479  bool isByRef = VD->hasAttr<BlocksAttr>();
4480
4481  uint64_t XOffset = 0;
4482  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
4483  llvm::DIType *Ty;
4484  if (isByRef)
4485    Ty = EmitTypeForVarWithBlocksAttr(VD, &XOffset).WrappedType;
4486  else
4487    Ty = getOrCreateType(VD->getType(), Unit);
4488
4489  // Self is passed along as an implicit non-arg variable in a
4490  // block. Mark it as the object pointer.
4491  if (const auto *IPD = dyn_cast<ImplicitParamDecl>(VD))
4492    if (IPD->getParameterKind() == ImplicitParamDecl::ObjCSelf)
4493      Ty = CreateSelfType(VD->getType(), Ty);
4494
4495  // Get location information.
4496  const unsigned Line =
4497      getLineNumber(VD->getLocation().isValid() ? VD->getLocation() : CurLoc);
4498  unsigned Column = getColumnNumber(VD->getLocation());
4499
4500  const llvm::DataLayout &target = CGM.getDataLayout();
4501
4502  CharUnits offset = CharUnits::fromQuantity(
4503      target.getStructLayout(blockInfo.StructureType)
4504          ->getElementOffset(blockInfo.getCapture(VD).getIndex()));
4505
4506  SmallVector<int64_t, 9> addr;
4507  addr.push_back(llvm::dwarf::DW_OP_deref);
4508  addr.push_back(llvm::dwarf::DW_OP_plus_uconst);
4509  addr.push_back(offset.getQuantity());
4510  if (isByRef) {
4511    addr.push_back(llvm::dwarf::DW_OP_deref);
4512    addr.push_back(llvm::dwarf::DW_OP_plus_uconst);
4513    // offset of __forwarding field
4514    offset =
4515        CGM.getContext().toCharUnitsFromBits(target.getPointerSizeInBits(0));
4516    addr.push_back(offset.getQuantity());
4517    addr.push_back(llvm::dwarf::DW_OP_deref);
4518    addr.push_back(llvm::dwarf::DW_OP_plus_uconst);
4519    // offset of x field
4520    offset = CGM.getContext().toCharUnitsFromBits(XOffset);
4521    addr.push_back(offset.getQuantity());
4522  }
4523
4524  // Create the descriptor for the variable.
4525  auto Align = getDeclAlignIfRequired(VD, CGM.getContext());
4526  auto *D = DBuilder.createAutoVariable(
4527      cast<llvm::DILocalScope>(LexicalBlockStack.back()), VD->getName(), Unit,
4528      Line, Ty, false, llvm::DINode::FlagZero, Align);
4529
4530  // Insert an llvm.dbg.declare into the current block.
4531  auto DL = llvm::DILocation::get(CGM.getLLVMContext(), Line, Column,
4532                                  LexicalBlockStack.back(), CurInlinedAt);
4533  auto *Expr = DBuilder.createExpression(addr);
4534  if (InsertPoint)
4535    DBuilder.insertDeclare(Storage, D, Expr, DL, InsertPoint);
4536  else
4537    DBuilder.insertDeclare(Storage, D, Expr, DL, Builder.GetInsertBlock());
4538}
4539
4540llvm::DILocalVariable *
4541CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
4542                                      unsigned ArgNo, CGBuilderTy &Builder) {
4543  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4544  return EmitDeclare(VD, AI, ArgNo, Builder);
4545}
4546
4547namespace {
4548struct BlockLayoutChunk {
4549  uint64_t OffsetInBits;
4550  const BlockDecl::Capture *Capture;
4551};
4552bool operator<(const BlockLayoutChunk &l, const BlockLayoutChunk &r) {
4553  return l.OffsetInBits < r.OffsetInBits;
4554}
4555} // namespace
4556
4557void CGDebugInfo::collectDefaultFieldsForBlockLiteralDeclare(
4558    const CGBlockInfo &Block, const ASTContext &Context, SourceLocation Loc,
4559    const llvm::StructLayout &BlockLayout, llvm::DIFile *Unit,
4560    SmallVectorImpl<llvm::Metadata *> &Fields) {
4561  // Blocks in OpenCL have unique constraints which make the standard fields
4562  // redundant while requiring size and align fields for enqueue_kernel. See
4563  // initializeForBlockHeader in CGBlocks.cpp
4564  if (CGM.getLangOpts().OpenCL) {
4565    Fields.push_back(createFieldType("__size", Context.IntTy, Loc, AS_public,
4566                                     BlockLayout.getElementOffsetInBits(0),
4567                                     Unit, Unit));
4568    Fields.push_back(createFieldType("__align", Context.IntTy, Loc, AS_public,
4569                                     BlockLayout.getElementOffsetInBits(1),
4570                                     Unit, Unit));
4571  } else {
4572    Fields.push_back(createFieldType("__isa", Context.VoidPtrTy, Loc, AS_public,
4573                                     BlockLayout.getElementOffsetInBits(0),
4574                                     Unit, Unit));
4575    Fields.push_back(createFieldType("__flags", Context.IntTy, Loc, AS_public,
4576                                     BlockLayout.getElementOffsetInBits(1),
4577                                     Unit, Unit));
4578    Fields.push_back(
4579        createFieldType("__reserved", Context.IntTy, Loc, AS_public,
4580                        BlockLayout.getElementOffsetInBits(2), Unit, Unit));
4581    auto *FnTy = Block.getBlockExpr()->getFunctionType();
4582    auto FnPtrType = CGM.getContext().getPointerType(FnTy->desugar());
4583    Fields.push_back(createFieldType("__FuncPtr", FnPtrType, Loc, AS_public,
4584                                     BlockLayout.getElementOffsetInBits(3),
4585                                     Unit, Unit));
4586    Fields.push_back(createFieldType(
4587        "__descriptor",
4588        Context.getPointerType(Block.NeedsCopyDispose
4589                                   ? Context.getBlockDescriptorExtendedType()
4590                                   : Context.getBlockDescriptorType()),
4591        Loc, AS_public, BlockLayout.getElementOffsetInBits(4), Unit, Unit));
4592  }
4593}
4594
4595void CGDebugInfo::EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
4596                                                       StringRef Name,
4597                                                       unsigned ArgNo,
4598                                                       llvm::AllocaInst *Alloca,
4599                                                       CGBuilderTy &Builder) {
4600  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4601  ASTContext &C = CGM.getContext();
4602  const BlockDecl *blockDecl = block.getBlockDecl();
4603
4604  // Collect some general information about the block's location.
4605  SourceLocation loc = blockDecl->getCaretLocation();
4606  llvm::DIFile *tunit = getOrCreateFile(loc);
4607  unsigned line = getLineNumber(loc);
4608  unsigned column = getColumnNumber(loc);
4609
4610  // Build the debug-info type for the block literal.
4611  getDeclContextDescriptor(blockDecl);
4612
4613  const llvm::StructLayout *blockLayout =
4614      CGM.getDataLayout().getStructLayout(block.StructureType);
4615
4616  SmallVector<llvm::Metadata *, 16> fields;
4617  collectDefaultFieldsForBlockLiteralDeclare(block, C, loc, *blockLayout, tunit,
4618                                             fields);
4619
4620  // We want to sort the captures by offset, not because DWARF
4621  // requires this, but because we're paranoid about debuggers.
4622  SmallVector<BlockLayoutChunk, 8> chunks;
4623
4624  // 'this' capture.
4625  if (blockDecl->capturesCXXThis()) {
4626    BlockLayoutChunk chunk;
4627    chunk.OffsetInBits =
4628        blockLayout->getElementOffsetInBits(block.CXXThisIndex);
4629    chunk.Capture = nullptr;
4630    chunks.push_back(chunk);
4631  }
4632
4633  // Variable captures.
4634  for (const auto &capture : blockDecl->captures()) {
4635    const VarDecl *variable = capture.getVariable();
4636    const CGBlockInfo::Capture &captureInfo = block.getCapture(variable);
4637
4638    // Ignore constant captures.
4639    if (captureInfo.isConstant())
4640      continue;
4641
4642    BlockLayoutChunk chunk;
4643    chunk.OffsetInBits =
4644        blockLayout->getElementOffsetInBits(captureInfo.getIndex());
4645    chunk.Capture = &capture;
4646    chunks.push_back(chunk);
4647  }
4648
4649  // Sort by offset.
4650  llvm::array_pod_sort(chunks.begin(), chunks.end());
4651
4652  for (const BlockLayoutChunk &Chunk : chunks) {
4653    uint64_t offsetInBits = Chunk.OffsetInBits;
4654    const BlockDecl::Capture *capture = Chunk.Capture;
4655
4656    // If we have a null capture, this must be the C++ 'this' capture.
4657    if (!capture) {
4658      QualType type;
4659      if (auto *Method =
4660              cast_or_null<CXXMethodDecl>(blockDecl->getNonClosureContext()))
4661        type = Method->getThisType();
4662      else if (auto *RDecl = dyn_cast<CXXRecordDecl>(blockDecl->getParent()))
4663        type = QualType(RDecl->getTypeForDecl(), 0);
4664      else
4665        llvm_unreachable("unexpected block declcontext");
4666
4667      fields.push_back(createFieldType("this", type, loc, AS_public,
4668                                       offsetInBits, tunit, tunit));
4669      continue;
4670    }
4671
4672    const VarDecl *variable = capture->getVariable();
4673    StringRef name = variable->getName();
4674
4675    llvm::DIType *fieldType;
4676    if (capture->isByRef()) {
4677      TypeInfo PtrInfo = C.getTypeInfo(C.VoidPtrTy);
4678      auto Align = PtrInfo.AlignIsRequired ? PtrInfo.Align : 0;
4679      // FIXME: This recomputes the layout of the BlockByRefWrapper.
4680      uint64_t xoffset;
4681      fieldType =
4682          EmitTypeForVarWithBlocksAttr(variable, &xoffset).BlockByRefWrapper;
4683      fieldType = DBuilder.createPointerType(fieldType, PtrInfo.Width);
4684      fieldType = DBuilder.createMemberType(tunit, name, tunit, line,
4685                                            PtrInfo.Width, Align, offsetInBits,
4686                                            llvm::DINode::FlagZero, fieldType);
4687    } else {
4688      auto Align = getDeclAlignIfRequired(variable, CGM.getContext());
4689      fieldType = createFieldType(name, variable->getType(), loc, AS_public,
4690                                  offsetInBits, Align, tunit, tunit);
4691    }
4692    fields.push_back(fieldType);
4693  }
4694
4695  SmallString<36> typeName;
4696  llvm::raw_svector_ostream(typeName)
4697      << "__block_literal_" << CGM.getUniqueBlockCount();
4698
4699  llvm::DINodeArray fieldsArray = DBuilder.getOrCreateArray(fields);
4700
4701  llvm::DIType *type =
4702      DBuilder.createStructType(tunit, typeName.str(), tunit, line,
4703                                CGM.getContext().toBits(block.BlockSize), 0,
4704                                llvm::DINode::FlagZero, nullptr, fieldsArray);
4705  type = DBuilder.createPointerType(type, CGM.PointerWidthInBits);
4706
4707  // Get overall information about the block.
4708  llvm::DINode::DIFlags flags = llvm::DINode::FlagArtificial;
4709  auto *scope = cast<llvm::DILocalScope>(LexicalBlockStack.back());
4710
4711  // Create the descriptor for the parameter.
4712  auto *debugVar = DBuilder.createParameterVariable(
4713      scope, Name, ArgNo, tunit, line, type, CGM.getLangOpts().Optimize, flags);
4714
4715  // Insert an llvm.dbg.declare into the current block.
4716  DBuilder.insertDeclare(Alloca, debugVar, DBuilder.createExpression(),
4717                         llvm::DILocation::get(CGM.getLLVMContext(), line,
4718                                               column, scope, CurInlinedAt),
4719                         Builder.GetInsertBlock());
4720}
4721
4722llvm::DIDerivedType *
4723CGDebugInfo::getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D) {
4724  if (!D || !D->isStaticDataMember())
4725    return nullptr;
4726
4727  auto MI = StaticDataMemberCache.find(D->getCanonicalDecl());
4728  if (MI != StaticDataMemberCache.end()) {
4729    assert(MI->second && "Static data member declaration should still exist");
4730    return MI->second;
4731  }
4732
4733  // If the member wasn't found in the cache, lazily construct and add it to the
4734  // type (used when a limited form of the type is emitted).
4735  auto DC = D->getDeclContext();
4736  auto *Ctxt = cast<llvm::DICompositeType>(getDeclContextDescriptor(D));
4737  return CreateRecordStaticField(D, Ctxt, cast<RecordDecl>(DC));
4738}
4739
4740llvm::DIGlobalVariableExpression *CGDebugInfo::CollectAnonRecordDecls(
4741    const RecordDecl *RD, llvm::DIFile *Unit, unsigned LineNo,
4742    StringRef LinkageName, llvm::GlobalVariable *Var, llvm::DIScope *DContext) {
4743  llvm::DIGlobalVariableExpression *GVE = nullptr;
4744
4745  for (const auto *Field : RD->fields()) {
4746    llvm::DIType *FieldTy = getOrCreateType(Field->getType(), Unit);
4747    StringRef FieldName = Field->getName();
4748
4749    // Ignore unnamed fields, but recurse into anonymous records.
4750    if (FieldName.empty()) {
4751      if (const auto *RT = dyn_cast<RecordType>(Field->getType()))
4752        GVE = CollectAnonRecordDecls(RT->getDecl(), Unit, LineNo, LinkageName,
4753                                     Var, DContext);
4754      continue;
4755    }
4756    // Use VarDecl's Tag, Scope and Line number.
4757    GVE = DBuilder.createGlobalVariableExpression(
4758        DContext, FieldName, LinkageName, Unit, LineNo, FieldTy,
4759        Var->hasLocalLinkage());
4760    Var->addDebugInfo(GVE);
4761  }
4762  return GVE;
4763}
4764
4765void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
4766                                     const VarDecl *D) {
4767  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4768  if (D->hasAttr<NoDebugAttr>())
4769    return;
4770
4771  llvm::TimeTraceScope TimeScope("DebugGlobalVariable", [&]() {
4772    std::string Name;
4773    llvm::raw_string_ostream OS(Name);
4774    D->getNameForDiagnostic(OS, getPrintingPolicy(),
4775                            /*Qualified=*/true);
4776    return Name;
4777  });
4778
4779  // If we already created a DIGlobalVariable for this declaration, just attach
4780  // it to the llvm::GlobalVariable.
4781  auto Cached = DeclCache.find(D->getCanonicalDecl());
4782  if (Cached != DeclCache.end())
4783    return Var->addDebugInfo(
4784        cast<llvm::DIGlobalVariableExpression>(Cached->second));
4785
4786  // Create global variable debug descriptor.
4787  llvm::DIFile *Unit = nullptr;
4788  llvm::DIScope *DContext = nullptr;
4789  unsigned LineNo;
4790  StringRef DeclName, LinkageName;
4791  QualType T;
4792  llvm::MDTuple *TemplateParameters = nullptr;
4793  collectVarDeclProps(D, Unit, LineNo, T, DeclName, LinkageName,
4794                      TemplateParameters, DContext);
4795
4796  // Attempt to store one global variable for the declaration - even if we
4797  // emit a lot of fields.
4798  llvm::DIGlobalVariableExpression *GVE = nullptr;
4799
4800  // If this is an anonymous union then we'll want to emit a global
4801  // variable for each member of the anonymous union so that it's possible
4802  // to find the name of any field in the union.
4803  if (T->isUnionType() && DeclName.empty()) {
4804    const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
4805    assert(RD->isAnonymousStructOrUnion() &&
4806           "unnamed non-anonymous struct or union?");
4807    GVE = CollectAnonRecordDecls(RD, Unit, LineNo, LinkageName, Var, DContext);
4808  } else {
4809    auto Align = getDeclAlignIfRequired(D, CGM.getContext());
4810
4811    SmallVector<int64_t, 4> Expr;
4812    unsigned AddressSpace =
4813        CGM.getContext().getTargetAddressSpace(D->getType());
4814    if (CGM.getLangOpts().CUDA && CGM.getLangOpts().CUDAIsDevice) {
4815      if (D->hasAttr<CUDASharedAttr>())
4816        AddressSpace =
4817            CGM.getContext().getTargetAddressSpace(LangAS::cuda_shared);
4818      else if (D->hasAttr<CUDAConstantAttr>())
4819        AddressSpace =
4820            CGM.getContext().getTargetAddressSpace(LangAS::cuda_constant);
4821    }
4822    AppendAddressSpaceXDeref(AddressSpace, Expr);
4823
4824    GVE = DBuilder.createGlobalVariableExpression(
4825        DContext, DeclName, LinkageName, Unit, LineNo, getOrCreateType(T, Unit),
4826        Var->hasLocalLinkage(), true,
4827        Expr.empty() ? nullptr : DBuilder.createExpression(Expr),
4828        getOrCreateStaticDataMemberDeclarationOrNull(D), TemplateParameters,
4829        Align);
4830    Var->addDebugInfo(GVE);
4831  }
4832  DeclCache[D->getCanonicalDecl()].reset(GVE);
4833}
4834
4835void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
4836  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4837  if (VD->hasAttr<NoDebugAttr>())
4838    return;
4839  llvm::TimeTraceScope TimeScope("DebugConstGlobalVariable", [&]() {
4840    std::string Name;
4841    llvm::raw_string_ostream OS(Name);
4842    VD->getNameForDiagnostic(OS, getPrintingPolicy(),
4843                             /*Qualified=*/true);
4844    return Name;
4845  });
4846
4847  auto Align = getDeclAlignIfRequired(VD, CGM.getContext());
4848  // Create the descriptor for the variable.
4849  llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
4850  StringRef Name = VD->getName();
4851  llvm::DIType *Ty = getOrCreateType(VD->getType(), Unit);
4852
4853  if (const auto *ECD = dyn_cast<EnumConstantDecl>(VD)) {
4854    const auto *ED = cast<EnumDecl>(ECD->getDeclContext());
4855    assert(isa<EnumType>(ED->getTypeForDecl()) && "Enum without EnumType?");
4856
4857    if (CGM.getCodeGenOpts().EmitCodeView) {
4858      // If CodeView, emit enums as global variables, unless they are defined
4859      // inside a class. We do this because MSVC doesn't emit S_CONSTANTs for
4860      // enums in classes, and because it is difficult to attach this scope
4861      // information to the global variable.
4862      if (isa<RecordDecl>(ED->getDeclContext()))
4863        return;
4864    } else {
4865      // If not CodeView, emit DW_TAG_enumeration_type if necessary. For
4866      // example: for "enum { ZERO };", a DW_TAG_enumeration_type is created the
4867      // first time `ZERO` is referenced in a function.
4868      llvm::DIType *EDTy =
4869          getOrCreateType(QualType(ED->getTypeForDecl(), 0), Unit);
4870      assert (EDTy->getTag() == llvm::dwarf::DW_TAG_enumeration_type);
4871      (void)EDTy;
4872      return;
4873    }
4874  }
4875
4876  // Do not emit separate definitions for function local consts.
4877  if (isa<FunctionDecl>(VD->getDeclContext()))
4878    return;
4879
4880  VD = cast<ValueDecl>(VD->getCanonicalDecl());
4881  auto *VarD = dyn_cast<VarDecl>(VD);
4882  if (VarD && VarD->isStaticDataMember()) {
4883    auto *RD = cast<RecordDecl>(VarD->getDeclContext());
4884    getDeclContextDescriptor(VarD);
4885    // Ensure that the type is retained even though it's otherwise unreferenced.
4886    //
4887    // FIXME: This is probably unnecessary, since Ty should reference RD
4888    // through its scope.
4889    RetainedTypes.push_back(
4890        CGM.getContext().getRecordType(RD).getAsOpaquePtr());
4891
4892    return;
4893  }
4894  llvm::DIScope *DContext = getDeclContextDescriptor(VD);
4895
4896  auto &GV = DeclCache[VD];
4897  if (GV)
4898    return;
4899  llvm::DIExpression *InitExpr = nullptr;
4900  if (CGM.getContext().getTypeSize(VD->getType()) <= 64) {
4901    // FIXME: Add a representation for integer constants wider than 64 bits.
4902    if (Init.isInt())
4903      InitExpr =
4904          DBuilder.createConstantValueExpression(Init.getInt().getExtValue());
4905    else if (Init.isFloat())
4906      InitExpr = DBuilder.createConstantValueExpression(
4907          Init.getFloat().bitcastToAPInt().getZExtValue());
4908  }
4909
4910  llvm::MDTuple *TemplateParameters = nullptr;
4911
4912  if (isa<VarTemplateSpecializationDecl>(VD))
4913    if (VarD) {
4914      llvm::DINodeArray parameterNodes = CollectVarTemplateParams(VarD, &*Unit);
4915      TemplateParameters = parameterNodes.get();
4916    }
4917
4918  GV.reset(DBuilder.createGlobalVariableExpression(
4919      DContext, Name, StringRef(), Unit, getLineNumber(VD->getLocation()), Ty,
4920      true, true, InitExpr, getOrCreateStaticDataMemberDeclarationOrNull(VarD),
4921      TemplateParameters, Align));
4922}
4923
4924void CGDebugInfo::EmitExternalVariable(llvm::GlobalVariable *Var,
4925                                       const VarDecl *D) {
4926  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
4927  if (D->hasAttr<NoDebugAttr>())
4928    return;
4929
4930  auto Align = getDeclAlignIfRequired(D, CGM.getContext());
4931  llvm::DIFile *Unit = getOrCreateFile(D->getLocation());
4932  StringRef Name = D->getName();
4933  llvm::DIType *Ty = getOrCreateType(D->getType(), Unit);
4934
4935  llvm::DIScope *DContext = getDeclContextDescriptor(D);
4936  llvm::DIGlobalVariableExpression *GVE =
4937      DBuilder.createGlobalVariableExpression(
4938          DContext, Name, StringRef(), Unit, getLineNumber(D->getLocation()),
4939          Ty, false, false, nullptr, nullptr, nullptr, Align);
4940  Var->addDebugInfo(GVE);
4941}
4942
4943llvm::DIScope *CGDebugInfo::getCurrentContextDescriptor(const Decl *D) {
4944  if (!LexicalBlockStack.empty())
4945    return LexicalBlockStack.back();
4946  llvm::DIScope *Mod = getParentModuleOrNull(D);
4947  return getContextDescriptor(D, Mod ? Mod : TheCU);
4948}
4949
4950void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
4951  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
4952    return;
4953  const NamespaceDecl *NSDecl = UD.getNominatedNamespace();
4954  if (!NSDecl->isAnonymousNamespace() ||
4955      CGM.getCodeGenOpts().DebugExplicitImport) {
4956    auto Loc = UD.getLocation();
4957    if (!Loc.isValid())
4958      Loc = CurLoc;
4959    DBuilder.createImportedModule(
4960        getCurrentContextDescriptor(cast<Decl>(UD.getDeclContext())),
4961        getOrCreateNamespace(NSDecl), getOrCreateFile(Loc), getLineNumber(Loc));
4962  }
4963}
4964
4965void CGDebugInfo::EmitUsingDecl(const UsingDecl &UD) {
4966  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
4967    return;
4968  assert(UD.shadow_size() &&
4969         "We shouldn't be codegening an invalid UsingDecl containing no decls");
4970  // Emitting one decl is sufficient - debuggers can detect that this is an
4971  // overloaded name & provide lookup for all the overloads.
4972  const UsingShadowDecl &USD = **UD.shadow_begin();
4973
4974  // FIXME: Skip functions with undeduced auto return type for now since we
4975  // don't currently have the plumbing for separate declarations & definitions
4976  // of free functions and mismatched types (auto in the declaration, concrete
4977  // return type in the definition)
4978  if (const auto *FD = dyn_cast<FunctionDecl>(USD.getUnderlyingDecl()))
4979    if (const auto *AT =
4980            FD->getType()->castAs<FunctionProtoType>()->getContainedAutoType())
4981      if (AT->getDeducedType().isNull())
4982        return;
4983  if (llvm::DINode *Target =
4984          getDeclarationOrDefinition(USD.getUnderlyingDecl())) {
4985    auto Loc = USD.getLocation();
4986    DBuilder.createImportedDeclaration(
4987        getCurrentContextDescriptor(cast<Decl>(USD.getDeclContext())), Target,
4988        getOrCreateFile(Loc), getLineNumber(Loc));
4989  }
4990}
4991
4992void CGDebugInfo::EmitImportDecl(const ImportDecl &ID) {
4993  if (CGM.getCodeGenOpts().getDebuggerTuning() != llvm::DebuggerKind::LLDB)
4994    return;
4995  if (Module *M = ID.getImportedModule()) {
4996    auto Info = ASTSourceDescriptor(*M);
4997    auto Loc = ID.getLocation();
4998    DBuilder.createImportedDeclaration(
4999        getCurrentContextDescriptor(cast<Decl>(ID.getDeclContext())),
5000        getOrCreateModuleRef(Info, DebugTypeExtRefs), getOrCreateFile(Loc),
5001        getLineNumber(Loc));
5002  }
5003}
5004
5005llvm::DIImportedEntity *
5006CGDebugInfo::EmitNamespaceAlias(const NamespaceAliasDecl &NA) {
5007  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
5008    return nullptr;
5009  auto &VH = NamespaceAliasCache[&NA];
5010  if (VH)
5011    return cast<llvm::DIImportedEntity>(VH);
5012  llvm::DIImportedEntity *R;
5013  auto Loc = NA.getLocation();
5014  if (const auto *Underlying =
5015          dyn_cast<NamespaceAliasDecl>(NA.getAliasedNamespace()))
5016    // This could cache & dedup here rather than relying on metadata deduping.
5017    R = DBuilder.createImportedDeclaration(
5018        getCurrentContextDescriptor(cast<Decl>(NA.getDeclContext())),
5019        EmitNamespaceAlias(*Underlying), getOrCreateFile(Loc),
5020        getLineNumber(Loc), NA.getName());
5021  else
5022    R = DBuilder.createImportedDeclaration(
5023        getCurrentContextDescriptor(cast<Decl>(NA.getDeclContext())),
5024        getOrCreateNamespace(cast<NamespaceDecl>(NA.getAliasedNamespace())),
5025        getOrCreateFile(Loc), getLineNumber(Loc), NA.getName());
5026  VH.reset(R);
5027  return R;
5028}
5029
5030llvm::DINamespace *
5031CGDebugInfo::getOrCreateNamespace(const NamespaceDecl *NSDecl) {
5032  // Don't canonicalize the NamespaceDecl here: The DINamespace will be uniqued
5033  // if necessary, and this way multiple declarations of the same namespace in
5034  // different parent modules stay distinct.
5035  auto I = NamespaceCache.find(NSDecl);
5036  if (I != NamespaceCache.end())
5037    return cast<llvm::DINamespace>(I->second);
5038
5039  llvm::DIScope *Context = getDeclContextDescriptor(NSDecl);
5040  // Don't trust the context if it is a DIModule (see comment above).
5041  llvm::DINamespace *NS =
5042      DBuilder.createNameSpace(Context, NSDecl->getName(), NSDecl->isInline());
5043  NamespaceCache[NSDecl].reset(NS);
5044  return NS;
5045}
5046
5047void CGDebugInfo::setDwoId(uint64_t Signature) {
5048  assert(TheCU && "no main compile unit");
5049  TheCU->setDWOId(Signature);
5050}
5051
5052void CGDebugInfo::finalize() {
5053  // Creating types might create further types - invalidating the current
5054  // element and the size(), so don't cache/reference them.
5055  for (size_t i = 0; i != ObjCInterfaceCache.size(); ++i) {
5056    ObjCInterfaceCacheEntry E = ObjCInterfaceCache[i];
5057    llvm::DIType *Ty = E.Type->getDecl()->getDefinition()
5058                           ? CreateTypeDefinition(E.Type, E.Unit)
5059                           : E.Decl;
5060    DBuilder.replaceTemporary(llvm::TempDIType(E.Decl), Ty);
5061  }
5062
5063  // Add methods to interface.
5064  for (const auto &P : ObjCMethodCache) {
5065    if (P.second.empty())
5066      continue;
5067
5068    QualType QTy(P.first->getTypeForDecl(), 0);
5069    auto It = TypeCache.find(QTy.getAsOpaquePtr());
5070    assert(It != TypeCache.end());
5071
5072    llvm::DICompositeType *InterfaceDecl =
5073        cast<llvm::DICompositeType>(It->second);
5074
5075    auto CurElts = InterfaceDecl->getElements();
5076    SmallVector<llvm::Metadata *, 16> EltTys(CurElts.begin(), CurElts.end());
5077
5078    // For DWARF v4 or earlier, only add objc_direct methods.
5079    for (auto &SubprogramDirect : P.second)
5080      if (CGM.getCodeGenOpts().DwarfVersion >= 5 || SubprogramDirect.getInt())
5081        EltTys.push_back(SubprogramDirect.getPointer());
5082
5083    llvm::DINodeArray Elements = DBuilder.getOrCreateArray(EltTys);
5084    DBuilder.replaceArrays(InterfaceDecl, Elements);
5085  }
5086
5087  for (const auto &P : ReplaceMap) {
5088    assert(P.second);
5089    auto *Ty = cast<llvm::DIType>(P.second);
5090    assert(Ty->isForwardDecl());
5091
5092    auto It = TypeCache.find(P.first);
5093    assert(It != TypeCache.end());
5094    assert(It->second);
5095
5096    DBuilder.replaceTemporary(llvm::TempDIType(Ty),
5097                              cast<llvm::DIType>(It->second));
5098  }
5099
5100  for (const auto &P : FwdDeclReplaceMap) {
5101    assert(P.second);
5102    llvm::TempMDNode FwdDecl(cast<llvm::MDNode>(P.second));
5103    llvm::Metadata *Repl;
5104
5105    auto It = DeclCache.find(P.first);
5106    // If there has been no definition for the declaration, call RAUW
5107    // with ourselves, that will destroy the temporary MDNode and
5108    // replace it with a standard one, avoiding leaking memory.
5109    if (It == DeclCache.end())
5110      Repl = P.second;
5111    else
5112      Repl = It->second;
5113
5114    if (auto *GVE = dyn_cast_or_null<llvm::DIGlobalVariableExpression>(Repl))
5115      Repl = GVE->getVariable();
5116    DBuilder.replaceTemporary(std::move(FwdDecl), cast<llvm::MDNode>(Repl));
5117  }
5118
5119  // We keep our own list of retained types, because we need to look
5120  // up the final type in the type cache.
5121  for (auto &RT : RetainedTypes)
5122    if (auto MD = TypeCache[RT])
5123      DBuilder.retainType(cast<llvm::DIType>(MD));
5124
5125  DBuilder.finalize();
5126}
5127
5128// Don't ignore in case of explicit cast where it is referenced indirectly.
5129void CGDebugInfo::EmitExplicitCastType(QualType Ty) {
5130  if (CGM.getCodeGenOpts().hasReducedDebugInfo())
5131    if (auto *DieTy = getOrCreateType(Ty, TheCU->getFile()))
5132      DBuilder.retainType(DieTy);
5133}
5134
5135void CGDebugInfo::EmitAndRetainType(QualType Ty) {
5136  if (CGM.getCodeGenOpts().hasMaybeUnusedDebugInfo())
5137    if (auto *DieTy = getOrCreateType(Ty, TheCU->getFile()))
5138      DBuilder.retainType(DieTy);
5139}
5140
5141llvm::DebugLoc CGDebugInfo::SourceLocToDebugLoc(SourceLocation Loc) {
5142  if (LexicalBlockStack.empty())
5143    return llvm::DebugLoc();
5144
5145  llvm::MDNode *Scope = LexicalBlockStack.back();
5146  return llvm::DILocation::get(CGM.getLLVMContext(), getLineNumber(Loc),
5147                               getColumnNumber(Loc), Scope);
5148}
5149
5150llvm::DINode::DIFlags CGDebugInfo::getCallSiteRelatedAttrs() const {
5151  // Call site-related attributes are only useful in optimized programs, and
5152  // when there's a possibility of debugging backtraces.
5153  if (!CGM.getLangOpts().Optimize || DebugKind == codegenoptions::NoDebugInfo ||
5154      DebugKind == codegenoptions::LocTrackingOnly)
5155    return llvm::DINode::FlagZero;
5156
5157  // Call site-related attributes are available in DWARF v5. Some debuggers,
5158  // while not fully DWARF v5-compliant, may accept these attributes as if they
5159  // were part of DWARF v4.
5160  bool SupportsDWARFv4Ext =
5161      CGM.getCodeGenOpts().DwarfVersion == 4 &&
5162      (CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::LLDB ||
5163       CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::GDB);
5164
5165  if (!SupportsDWARFv4Ext && CGM.getCodeGenOpts().DwarfVersion < 5)
5166    return llvm::DINode::FlagZero;
5167
5168  return llvm::DINode::FlagAllCallsDescribed;
5169}
5170