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      1 //===--- ARCMT.cpp - Migration to ARC mode --------------------------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 
     10 #include "Internals.h"
     11 #include "clang/AST/ASTConsumer.h"
     12 #include "clang/Basic/DiagnosticCategories.h"
     13 #include "clang/Frontend/ASTUnit.h"
     14 #include "clang/Frontend/CompilerInstance.h"
     15 #include "clang/Frontend/FrontendAction.h"
     16 #include "clang/Frontend/TextDiagnosticPrinter.h"
     17 #include "clang/Frontend/Utils.h"
     18 #include "clang/Lex/Preprocessor.h"
     19 #include "clang/Rewrite/Core/Rewriter.h"
     20 #include "clang/Sema/SemaDiagnostic.h"
     21 #include "clang/Serialization/ASTReader.h"
     22 #include "llvm/ADT/Triple.h"
     23 #include "llvm/Support/MemoryBuffer.h"
     24 using namespace clang;
     25 using namespace arcmt;
     26 
     27 bool CapturedDiagList::clearDiagnostic(ArrayRef<unsigned> IDs,
     28                                        SourceRange range) {
     29   if (range.isInvalid())
     30     return false;
     31 
     32   bool cleared = false;
     33   ListTy::iterator I = List.begin();
     34   while (I != List.end()) {
     35     FullSourceLoc diagLoc = I->getLocation();
     36     if ((IDs.empty() || // empty means clear all diagnostics in the range.
     37          std::find(IDs.begin(), IDs.end(), I->getID()) != IDs.end()) &&
     38         !diagLoc.isBeforeInTranslationUnitThan(range.getBegin()) &&
     39         (diagLoc == range.getEnd() ||
     40            diagLoc.isBeforeInTranslationUnitThan(range.getEnd()))) {
     41       cleared = true;
     42       ListTy::iterator eraseS = I++;
     43       if (eraseS->getLevel() != DiagnosticsEngine::Note)
     44         while (I != List.end() && I->getLevel() == DiagnosticsEngine::Note)
     45           ++I;
     46       // Clear the diagnostic and any notes following it.
     47       I = List.erase(eraseS, I);
     48       continue;
     49     }
     50 
     51     ++I;
     52   }
     53 
     54   return cleared;
     55 }
     56 
     57 bool CapturedDiagList::hasDiagnostic(ArrayRef<unsigned> IDs,
     58                                      SourceRange range) const {
     59   if (range.isInvalid())
     60     return false;
     61 
     62   ListTy::const_iterator I = List.begin();
     63   while (I != List.end()) {
     64     FullSourceLoc diagLoc = I->getLocation();
     65     if ((IDs.empty() || // empty means any diagnostic in the range.
     66          std::find(IDs.begin(), IDs.end(), I->getID()) != IDs.end()) &&
     67         !diagLoc.isBeforeInTranslationUnitThan(range.getBegin()) &&
     68         (diagLoc == range.getEnd() ||
     69            diagLoc.isBeforeInTranslationUnitThan(range.getEnd()))) {
     70       return true;
     71     }
     72 
     73     ++I;
     74   }
     75 
     76   return false;
     77 }
     78 
     79 void CapturedDiagList::reportDiagnostics(DiagnosticsEngine &Diags) const {
     80   for (ListTy::const_iterator I = List.begin(), E = List.end(); I != E; ++I)
     81     Diags.Report(*I);
     82 }
     83 
     84 bool CapturedDiagList::hasErrors() const {
     85   for (ListTy::const_iterator I = List.begin(), E = List.end(); I != E; ++I)
     86     if (I->getLevel() >= DiagnosticsEngine::Error)
     87       return true;
     88 
     89   return false;
     90 }
     91 
     92 namespace {
     93 
     94 class CaptureDiagnosticConsumer : public DiagnosticConsumer {
     95   DiagnosticsEngine &Diags;
     96   DiagnosticConsumer &DiagClient;
     97   CapturedDiagList &CapturedDiags;
     98   bool HasBegunSourceFile;
     99 public:
    100   CaptureDiagnosticConsumer(DiagnosticsEngine &diags,
    101                             DiagnosticConsumer &client,
    102                             CapturedDiagList &capturedDiags)
    103     : Diags(diags), DiagClient(client), CapturedDiags(capturedDiags),
    104       HasBegunSourceFile(false) { }
    105 
    106   void BeginSourceFile(const LangOptions &Opts,
    107                        const Preprocessor *PP) override {
    108     // Pass BeginSourceFile message onto DiagClient on first call.
    109     // The corresponding EndSourceFile call will be made from an
    110     // explicit call to FinishCapture.
    111     if (!HasBegunSourceFile) {
    112       DiagClient.BeginSourceFile(Opts, PP);
    113       HasBegunSourceFile = true;
    114     }
    115   }
    116 
    117   void FinishCapture() {
    118     // Call EndSourceFile on DiagClient on completion of capture to
    119     // enable VerifyDiagnosticConsumer to check diagnostics *after*
    120     // it has received the diagnostic list.
    121     if (HasBegunSourceFile) {
    122       DiagClient.EndSourceFile();
    123       HasBegunSourceFile = false;
    124     }
    125   }
    126 
    127   ~CaptureDiagnosticConsumer() override {
    128     assert(!HasBegunSourceFile && "FinishCapture not called!");
    129   }
    130 
    131   void HandleDiagnostic(DiagnosticsEngine::Level level,
    132                         const Diagnostic &Info) override {
    133     if (DiagnosticIDs::isARCDiagnostic(Info.getID()) ||
    134         level >= DiagnosticsEngine::Error || level == DiagnosticsEngine::Note) {
    135       if (Info.getLocation().isValid())
    136         CapturedDiags.push_back(StoredDiagnostic(level, Info));
    137       return;
    138     }
    139 
    140     // Non-ARC warnings are ignored.
    141     Diags.setLastDiagnosticIgnored();
    142   }
    143 };
    144 
    145 } // end anonymous namespace
    146 
    147 static bool HasARCRuntime(CompilerInvocation &origCI) {
    148   // This duplicates some functionality from Darwin::AddDeploymentTarget
    149   // but this function is well defined, so keep it decoupled from the driver
    150   // and avoid unrelated complications.
    151   llvm::Triple triple(origCI.getTargetOpts().Triple);
    152 
    153   if (triple.isiOS())
    154     return triple.getOSMajorVersion() >= 5;
    155 
    156   if (triple.isWatchOS())
    157     return true;
    158 
    159   if (triple.getOS() == llvm::Triple::Darwin)
    160     return triple.getOSMajorVersion() >= 11;
    161 
    162   if (triple.getOS() == llvm::Triple::MacOSX) {
    163     unsigned Major, Minor, Micro;
    164     triple.getOSVersion(Major, Minor, Micro);
    165     return Major > 10 || (Major == 10 && Minor >= 7);
    166   }
    167 
    168   return false;
    169 }
    170 
    171 static CompilerInvocation *
    172 createInvocationForMigration(CompilerInvocation &origCI,
    173                              const PCHContainerReader &PCHContainerRdr) {
    174   std::unique_ptr<CompilerInvocation> CInvok;
    175   CInvok.reset(new CompilerInvocation(origCI));
    176   PreprocessorOptions &PPOpts = CInvok->getPreprocessorOpts();
    177   if (!PPOpts.ImplicitPCHInclude.empty()) {
    178     // We can't use a PCH because it was likely built in non-ARC mode and we
    179     // want to parse in ARC. Include the original header.
    180     FileManager FileMgr(origCI.getFileSystemOpts());
    181     IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    182     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    183         new DiagnosticsEngine(DiagID, &origCI.getDiagnosticOpts(),
    184                               new IgnoringDiagConsumer()));
    185     std::string OriginalFile = ASTReader::getOriginalSourceFile(
    186         PPOpts.ImplicitPCHInclude, FileMgr, PCHContainerRdr, *Diags);
    187     if (!OriginalFile.empty())
    188       PPOpts.Includes.insert(PPOpts.Includes.begin(), OriginalFile);
    189     PPOpts.ImplicitPCHInclude.clear();
    190   }
    191   // FIXME: Get the original header of a PTH as well.
    192   CInvok->getPreprocessorOpts().ImplicitPTHInclude.clear();
    193   std::string define = getARCMTMacroName();
    194   define += '=';
    195   CInvok->getPreprocessorOpts().addMacroDef(define);
    196   CInvok->getLangOpts()->ObjCAutoRefCount = true;
    197   CInvok->getLangOpts()->setGC(LangOptions::NonGC);
    198   CInvok->getDiagnosticOpts().ErrorLimit = 0;
    199   CInvok->getDiagnosticOpts().PedanticErrors = 0;
    200 
    201   // Ignore -Werror flags when migrating.
    202   std::vector<std::string> WarnOpts;
    203   for (std::vector<std::string>::iterator
    204          I = CInvok->getDiagnosticOpts().Warnings.begin(),
    205          E = CInvok->getDiagnosticOpts().Warnings.end(); I != E; ++I) {
    206     if (!StringRef(*I).startswith("error"))
    207       WarnOpts.push_back(*I);
    208   }
    209   WarnOpts.push_back("error=arc-unsafe-retained-assign");
    210   CInvok->getDiagnosticOpts().Warnings = std::move(WarnOpts);
    211 
    212   CInvok->getLangOpts()->ObjCWeakRuntime = HasARCRuntime(origCI);
    213   CInvok->getLangOpts()->ObjCWeak = CInvok->getLangOpts()->ObjCWeakRuntime;
    214 
    215   return CInvok.release();
    216 }
    217 
    218 static void emitPremigrationErrors(const CapturedDiagList &arcDiags,
    219                                    DiagnosticOptions *diagOpts,
    220                                    Preprocessor &PP) {
    221   TextDiagnosticPrinter printer(llvm::errs(), diagOpts);
    222   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    223   IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    224       new DiagnosticsEngine(DiagID, diagOpts, &printer,
    225                             /*ShouldOwnClient=*/false));
    226   Diags->setSourceManager(&PP.getSourceManager());
    227 
    228   printer.BeginSourceFile(PP.getLangOpts(), &PP);
    229   arcDiags.reportDiagnostics(*Diags);
    230   printer.EndSourceFile();
    231 }
    232 
    233 //===----------------------------------------------------------------------===//
    234 // checkForManualIssues.
    235 //===----------------------------------------------------------------------===//
    236 
    237 bool arcmt::checkForManualIssues(
    238     CompilerInvocation &origCI, const FrontendInputFile &Input,
    239     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
    240     DiagnosticConsumer *DiagClient, bool emitPremigrationARCErrors,
    241     StringRef plistOut) {
    242   if (!origCI.getLangOpts()->ObjC1)
    243     return false;
    244 
    245   LangOptions::GCMode OrigGCMode = origCI.getLangOpts()->getGC();
    246   bool NoNSAllocReallocError = origCI.getMigratorOpts().NoNSAllocReallocError;
    247   bool NoFinalizeRemoval = origCI.getMigratorOpts().NoFinalizeRemoval;
    248 
    249   std::vector<TransformFn> transforms = arcmt::getAllTransformations(OrigGCMode,
    250                                                                      NoFinalizeRemoval);
    251   assert(!transforms.empty());
    252 
    253   std::unique_ptr<CompilerInvocation> CInvok;
    254   CInvok.reset(
    255       createInvocationForMigration(origCI, PCHContainerOps->getRawReader()));
    256   CInvok->getFrontendOpts().Inputs.clear();
    257   CInvok->getFrontendOpts().Inputs.push_back(Input);
    258 
    259   CapturedDiagList capturedDiags;
    260 
    261   assert(DiagClient);
    262   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    263   IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    264       new DiagnosticsEngine(DiagID, &origCI.getDiagnosticOpts(),
    265                             DiagClient, /*ShouldOwnClient=*/false));
    266 
    267   // Filter of all diagnostics.
    268   CaptureDiagnosticConsumer errRec(*Diags, *DiagClient, capturedDiags);
    269   Diags->setClient(&errRec, /*ShouldOwnClient=*/false);
    270 
    271   std::unique_ptr<ASTUnit> Unit(ASTUnit::LoadFromCompilerInvocationAction(
    272       CInvok.release(), PCHContainerOps, Diags));
    273   if (!Unit) {
    274     errRec.FinishCapture();
    275     return true;
    276   }
    277 
    278   // Don't filter diagnostics anymore.
    279   Diags->setClient(DiagClient, /*ShouldOwnClient=*/false);
    280 
    281   ASTContext &Ctx = Unit->getASTContext();
    282 
    283   if (Diags->hasFatalErrorOccurred()) {
    284     Diags->Reset();
    285     DiagClient->BeginSourceFile(Ctx.getLangOpts(), &Unit->getPreprocessor());
    286     capturedDiags.reportDiagnostics(*Diags);
    287     DiagClient->EndSourceFile();
    288     errRec.FinishCapture();
    289     return true;
    290   }
    291 
    292   if (emitPremigrationARCErrors)
    293     emitPremigrationErrors(capturedDiags, &origCI.getDiagnosticOpts(),
    294                            Unit->getPreprocessor());
    295   if (!plistOut.empty()) {
    296     SmallVector<StoredDiagnostic, 8> arcDiags;
    297     for (CapturedDiagList::iterator
    298            I = capturedDiags.begin(), E = capturedDiags.end(); I != E; ++I)
    299       arcDiags.push_back(*I);
    300     writeARCDiagsToPlist(plistOut, arcDiags,
    301                          Ctx.getSourceManager(), Ctx.getLangOpts());
    302   }
    303 
    304   // After parsing of source files ended, we want to reuse the
    305   // diagnostics objects to emit further diagnostics.
    306   // We call BeginSourceFile because DiagnosticConsumer requires that
    307   // diagnostics with source range information are emitted only in between
    308   // BeginSourceFile() and EndSourceFile().
    309   DiagClient->BeginSourceFile(Ctx.getLangOpts(), &Unit->getPreprocessor());
    310 
    311   // No macros will be added since we are just checking and we won't modify
    312   // source code.
    313   std::vector<SourceLocation> ARCMTMacroLocs;
    314 
    315   TransformActions testAct(*Diags, capturedDiags, Ctx, Unit->getPreprocessor());
    316   MigrationPass pass(Ctx, OrigGCMode, Unit->getSema(), testAct, capturedDiags,
    317                      ARCMTMacroLocs);
    318   pass.setNoFinalizeRemoval(NoFinalizeRemoval);
    319   if (!NoNSAllocReallocError)
    320     Diags->setSeverity(diag::warn_arcmt_nsalloc_realloc, diag::Severity::Error,
    321                        SourceLocation());
    322 
    323   for (unsigned i=0, e = transforms.size(); i != e; ++i)
    324     transforms[i](pass);
    325 
    326   capturedDiags.reportDiagnostics(*Diags);
    327 
    328   DiagClient->EndSourceFile();
    329   errRec.FinishCapture();
    330 
    331   return capturedDiags.hasErrors() || testAct.hasReportedErrors();
    332 }
    333 
    334 //===----------------------------------------------------------------------===//
    335 // applyTransformations.
    336 //===----------------------------------------------------------------------===//
    337 
    338 static bool
    339 applyTransforms(CompilerInvocation &origCI, const FrontendInputFile &Input,
    340                 std::shared_ptr<PCHContainerOperations> PCHContainerOps,
    341                 DiagnosticConsumer *DiagClient, StringRef outputDir,
    342                 bool emitPremigrationARCErrors, StringRef plistOut) {
    343   if (!origCI.getLangOpts()->ObjC1)
    344     return false;
    345 
    346   LangOptions::GCMode OrigGCMode = origCI.getLangOpts()->getGC();
    347 
    348   // Make sure checking is successful first.
    349   CompilerInvocation CInvokForCheck(origCI);
    350   if (arcmt::checkForManualIssues(CInvokForCheck, Input, PCHContainerOps,
    351                                   DiagClient, emitPremigrationARCErrors,
    352                                   plistOut))
    353     return true;
    354 
    355   CompilerInvocation CInvok(origCI);
    356   CInvok.getFrontendOpts().Inputs.clear();
    357   CInvok.getFrontendOpts().Inputs.push_back(Input);
    358 
    359   MigrationProcess migration(CInvok, PCHContainerOps, DiagClient, outputDir);
    360   bool NoFinalizeRemoval = origCI.getMigratorOpts().NoFinalizeRemoval;
    361 
    362   std::vector<TransformFn> transforms = arcmt::getAllTransformations(OrigGCMode,
    363                                                                      NoFinalizeRemoval);
    364   assert(!transforms.empty());
    365 
    366   for (unsigned i=0, e = transforms.size(); i != e; ++i) {
    367     bool err = migration.applyTransform(transforms[i]);
    368     if (err) return true;
    369   }
    370 
    371   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    372   IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    373       new DiagnosticsEngine(DiagID, &origCI.getDiagnosticOpts(),
    374                             DiagClient, /*ShouldOwnClient=*/false));
    375 
    376   if (outputDir.empty()) {
    377     origCI.getLangOpts()->ObjCAutoRefCount = true;
    378     return migration.getRemapper().overwriteOriginal(*Diags);
    379   } else {
    380     return migration.getRemapper().flushToDisk(outputDir, *Diags);
    381   }
    382 }
    383 
    384 bool arcmt::applyTransformations(
    385     CompilerInvocation &origCI, const FrontendInputFile &Input,
    386     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
    387     DiagnosticConsumer *DiagClient) {
    388   return applyTransforms(origCI, Input, PCHContainerOps, DiagClient,
    389                          StringRef(), false, StringRef());
    390 }
    391 
    392 bool arcmt::migrateWithTemporaryFiles(
    393     CompilerInvocation &origCI, const FrontendInputFile &Input,
    394     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
    395     DiagnosticConsumer *DiagClient, StringRef outputDir,
    396     bool emitPremigrationARCErrors, StringRef plistOut) {
    397   assert(!outputDir.empty() && "Expected output directory path");
    398   return applyTransforms(origCI, Input, PCHContainerOps, DiagClient, outputDir,
    399                          emitPremigrationARCErrors, plistOut);
    400 }
    401 
    402 bool arcmt::getFileRemappings(std::vector<std::pair<std::string,std::string> > &
    403                                   remap,
    404                               StringRef outputDir,
    405                               DiagnosticConsumer *DiagClient) {
    406   assert(!outputDir.empty());
    407 
    408   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    409   IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    410       new DiagnosticsEngine(DiagID, new DiagnosticOptions,
    411                             DiagClient, /*ShouldOwnClient=*/false));
    412 
    413   FileRemapper remapper;
    414   bool err = remapper.initFromDisk(outputDir, *Diags,
    415                                    /*ignoreIfFilesChanged=*/true);
    416   if (err)
    417     return true;
    418 
    419   PreprocessorOptions PPOpts;
    420   remapper.applyMappings(PPOpts);
    421   remap = PPOpts.RemappedFiles;
    422 
    423   return false;
    424 }
    425 
    426 
    427 //===----------------------------------------------------------------------===//
    428 // CollectTransformActions.
    429 //===----------------------------------------------------------------------===//
    430 
    431 namespace {
    432 
    433 class ARCMTMacroTrackerPPCallbacks : public PPCallbacks {
    434   std::vector<SourceLocation> &ARCMTMacroLocs;
    435 
    436 public:
    437   ARCMTMacroTrackerPPCallbacks(std::vector<SourceLocation> &ARCMTMacroLocs)
    438     : ARCMTMacroLocs(ARCMTMacroLocs) { }
    439 
    440   void MacroExpands(const Token &MacroNameTok, const MacroDefinition &MD,
    441                     SourceRange Range, const MacroArgs *Args) override {
    442     if (MacroNameTok.getIdentifierInfo()->getName() == getARCMTMacroName())
    443       ARCMTMacroLocs.push_back(MacroNameTok.getLocation());
    444   }
    445 };
    446 
    447 class ARCMTMacroTrackerAction : public ASTFrontendAction {
    448   std::vector<SourceLocation> &ARCMTMacroLocs;
    449 
    450 public:
    451   ARCMTMacroTrackerAction(std::vector<SourceLocation> &ARCMTMacroLocs)
    452     : ARCMTMacroLocs(ARCMTMacroLocs) { }
    453 
    454   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
    455                                                  StringRef InFile) override {
    456     CI.getPreprocessor().addPPCallbacks(
    457                llvm::make_unique<ARCMTMacroTrackerPPCallbacks>(ARCMTMacroLocs));
    458     return llvm::make_unique<ASTConsumer>();
    459   }
    460 };
    461 
    462 class RewritesApplicator : public TransformActions::RewriteReceiver {
    463   Rewriter &rewriter;
    464   MigrationProcess::RewriteListener *Listener;
    465 
    466 public:
    467   RewritesApplicator(Rewriter &rewriter, ASTContext &ctx,
    468                      MigrationProcess::RewriteListener *listener)
    469     : rewriter(rewriter), Listener(listener) {
    470     if (Listener)
    471       Listener->start(ctx);
    472   }
    473   ~RewritesApplicator() override {
    474     if (Listener)
    475       Listener->finish();
    476   }
    477 
    478   void insert(SourceLocation loc, StringRef text) override {
    479     bool err = rewriter.InsertText(loc, text, /*InsertAfter=*/true,
    480                                    /*indentNewLines=*/true);
    481     if (!err && Listener)
    482       Listener->insert(loc, text);
    483   }
    484 
    485   void remove(CharSourceRange range) override {
    486     Rewriter::RewriteOptions removeOpts;
    487     removeOpts.IncludeInsertsAtBeginOfRange = false;
    488     removeOpts.IncludeInsertsAtEndOfRange = false;
    489     removeOpts.RemoveLineIfEmpty = true;
    490 
    491     bool err = rewriter.RemoveText(range, removeOpts);
    492     if (!err && Listener)
    493       Listener->remove(range);
    494   }
    495 
    496   void increaseIndentation(CharSourceRange range,
    497                             SourceLocation parentIndent) override {
    498     rewriter.IncreaseIndentation(range, parentIndent);
    499   }
    500 };
    501 
    502 } // end anonymous namespace.
    503 
    504 /// \brief Anchor for VTable.
    505 MigrationProcess::RewriteListener::~RewriteListener() { }
    506 
    507 MigrationProcess::MigrationProcess(
    508     const CompilerInvocation &CI,
    509     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
    510     DiagnosticConsumer *diagClient, StringRef outputDir)
    511     : OrigCI(CI), PCHContainerOps(PCHContainerOps), DiagClient(diagClient),
    512       HadARCErrors(false) {
    513   if (!outputDir.empty()) {
    514     IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    515     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    516       new DiagnosticsEngine(DiagID, &CI.getDiagnosticOpts(),
    517                             DiagClient, /*ShouldOwnClient=*/false));
    518     Remapper.initFromDisk(outputDir, *Diags, /*ignoreIfFilesChanges=*/true);
    519   }
    520 }
    521 
    522 bool MigrationProcess::applyTransform(TransformFn trans,
    523                                       RewriteListener *listener) {
    524   std::unique_ptr<CompilerInvocation> CInvok;
    525   CInvok.reset(
    526       createInvocationForMigration(OrigCI, PCHContainerOps->getRawReader()));
    527   CInvok->getDiagnosticOpts().IgnoreWarnings = true;
    528 
    529   Remapper.applyMappings(CInvok->getPreprocessorOpts());
    530 
    531   CapturedDiagList capturedDiags;
    532   std::vector<SourceLocation> ARCMTMacroLocs;
    533 
    534   assert(DiagClient);
    535   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
    536   IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
    537       new DiagnosticsEngine(DiagID, new DiagnosticOptions,
    538                             DiagClient, /*ShouldOwnClient=*/false));
    539 
    540   // Filter of all diagnostics.
    541   CaptureDiagnosticConsumer errRec(*Diags, *DiagClient, capturedDiags);
    542   Diags->setClient(&errRec, /*ShouldOwnClient=*/false);
    543 
    544   std::unique_ptr<ARCMTMacroTrackerAction> ASTAction;
    545   ASTAction.reset(new ARCMTMacroTrackerAction(ARCMTMacroLocs));
    546 
    547   std::unique_ptr<ASTUnit> Unit(ASTUnit::LoadFromCompilerInvocationAction(
    548       CInvok.release(), PCHContainerOps, Diags, ASTAction.get()));
    549   if (!Unit) {
    550     errRec.FinishCapture();
    551     return true;
    552   }
    553   Unit->setOwnsRemappedFileBuffers(false); // FileRemapper manages that.
    554 
    555   HadARCErrors = HadARCErrors || capturedDiags.hasErrors();
    556 
    557   // Don't filter diagnostics anymore.
    558   Diags->setClient(DiagClient, /*ShouldOwnClient=*/false);
    559 
    560   ASTContext &Ctx = Unit->getASTContext();
    561 
    562   if (Diags->hasFatalErrorOccurred()) {
    563     Diags->Reset();
    564     DiagClient->BeginSourceFile(Ctx.getLangOpts(), &Unit->getPreprocessor());
    565     capturedDiags.reportDiagnostics(*Diags);
    566     DiagClient->EndSourceFile();
    567     errRec.FinishCapture();
    568     return true;
    569   }
    570 
    571   // After parsing of source files ended, we want to reuse the
    572   // diagnostics objects to emit further diagnostics.
    573   // We call BeginSourceFile because DiagnosticConsumer requires that
    574   // diagnostics with source range information are emitted only in between
    575   // BeginSourceFile() and EndSourceFile().
    576   DiagClient->BeginSourceFile(Ctx.getLangOpts(), &Unit->getPreprocessor());
    577 
    578   Rewriter rewriter(Ctx.getSourceManager(), Ctx.getLangOpts());
    579   TransformActions TA(*Diags, capturedDiags, Ctx, Unit->getPreprocessor());
    580   MigrationPass pass(Ctx, OrigCI.getLangOpts()->getGC(),
    581                      Unit->getSema(), TA, capturedDiags, ARCMTMacroLocs);
    582 
    583   trans(pass);
    584 
    585   {
    586     RewritesApplicator applicator(rewriter, Ctx, listener);
    587     TA.applyRewrites(applicator);
    588   }
    589 
    590   DiagClient->EndSourceFile();
    591   errRec.FinishCapture();
    592 
    593   if (DiagClient->getNumErrors())
    594     return true;
    595 
    596   for (Rewriter::buffer_iterator
    597         I = rewriter.buffer_begin(), E = rewriter.buffer_end(); I != E; ++I) {
    598     FileID FID = I->first;
    599     RewriteBuffer &buf = I->second;
    600     const FileEntry *file = Ctx.getSourceManager().getFileEntryForID(FID);
    601     assert(file);
    602     std::string newFname = file->getName();
    603     newFname += "-trans";
    604     SmallString<512> newText;
    605     llvm::raw_svector_ostream vecOS(newText);
    606     buf.write(vecOS);
    607     std::unique_ptr<llvm::MemoryBuffer> memBuf(
    608         llvm::MemoryBuffer::getMemBufferCopy(
    609             StringRef(newText.data(), newText.size()), newFname));
    610     SmallString<64> filePath(file->getName());
    611     Unit->getFileManager().FixupRelativePath(filePath);
    612     Remapper.remap(filePath.str(), std::move(memBuf));
    613   }
    614 
    615   return false;
    616 }
    617