clang/lib/Frontend/ASTUnit.cpp

   1 //===- ASTUnit.cpp - ASTUnit utility --------------------------------------===//
   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 // ASTUnit Implementation.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "clang/Frontend/ASTUnit.h"
  14 #include "clang/AST/ASTConsumer.h"
  15 #include "clang/AST/ASTContext.h"
  16 #include "clang/AST/CommentCommandTraits.h"
  17 #include "clang/AST/Decl.h"
  18 #include "clang/AST/DeclBase.h"
  19 #include "clang/AST/DeclCXX.h"
  20 #include "clang/AST/DeclGroup.h"
  21 #include "clang/AST/DeclObjC.h"
  22 #include "clang/AST/DeclTemplate.h"
  23 #include "clang/AST/DeclarationName.h"
  24 #include "clang/AST/ExternalASTSource.h"
  25 #include "clang/AST/PrettyPrinter.h"
  26 #include "clang/AST/Type.h"
  27 #include "clang/AST/TypeOrdering.h"
  28 #include "clang/Basic/Diagnostic.h"
  29 #include "clang/Basic/FileManager.h"
  30 #include "clang/Basic/IdentifierTable.h"
  31 #include "clang/Basic/LLVM.h"
  32 #include "clang/Basic/LangOptions.h"
  33 #include "clang/Basic/LangStandard.h"
  34 #include "clang/Basic/Module.h"
  35 #include "clang/Basic/SourceLocation.h"
  36 #include "clang/Basic/SourceManager.h"
  37 #include "clang/Basic/TargetInfo.h"
  38 #include "clang/Basic/TargetOptions.h"
  39 #include "clang/Frontend/CompilerInstance.h"
  40 #include "clang/Frontend/CompilerInvocation.h"
  41 #include "clang/Frontend/FrontendAction.h"
  42 #include "clang/Frontend/FrontendActions.h"
  43 #include "clang/Frontend/FrontendDiagnostic.h"
  44 #include "clang/Frontend/FrontendOptions.h"
  45 #include "clang/Frontend/MultiplexConsumer.h"
  46 #include "clang/Frontend/PrecompiledPreamble.h"
  47 #include "clang/Frontend/Utils.h"
  48 #include "clang/Lex/HeaderSearch.h"
  49 #include "clang/Lex/HeaderSearchOptions.h"
  50 #include "clang/Lex/Lexer.h"
  51 #include "clang/Lex/PPCallbacks.h"
  52 #include "clang/Lex/PreprocessingRecord.h"
  53 #include "clang/Lex/Preprocessor.h"
  54 #include "clang/Lex/PreprocessorOptions.h"
  55 #include "clang/Lex/Token.h"
  56 #include "clang/Sema/CodeCompleteConsumer.h"
  57 #include "clang/Sema/CodeCompleteOptions.h"
  58 #include "clang/Sema/Sema.h"
  59 #include "clang/Serialization/ASTBitCodes.h"
  60 #include "clang/Serialization/ASTReader.h"
  61 #include "clang/Serialization/ASTWriter.h"
  62 #include "clang/Serialization/ContinuousRangeMap.h"
  63 #include "clang/Serialization/InMemoryModuleCache.h"
  64 #include "clang/Serialization/ModuleFile.h"
  65 #include "clang/Serialization/PCHContainerOperations.h"
  66 #include "llvm/ADT/ArrayRef.h"
  67 #include "llvm/ADT/DenseMap.h"
  68 #include "llvm/ADT/IntrusiveRefCntPtr.h"
  69 #include "llvm/ADT/STLExtras.h"
  70 #include "llvm/ADT/ScopeExit.h"
  71 #include "llvm/ADT/SmallVector.h"
  72 #include "llvm/ADT/StringMap.h"
  73 #include "llvm/ADT/StringRef.h"
  74 #include "llvm/ADT/StringSet.h"
  75 #include "llvm/ADT/Twine.h"
  76 #include "llvm/ADT/iterator_range.h"
  77 #include "llvm/Bitstream/BitstreamWriter.h"
  78 #include "llvm/Support/Allocator.h"
  79 #include "llvm/Support/Casting.h"
  80 #include "llvm/Support/CrashRecoveryContext.h"
  81 #include "llvm/Support/DJB.h"
  82 #include "llvm/Support/ErrorHandling.h"
  83 #include "llvm/Support/ErrorOr.h"
  84 #include "llvm/Support/FileSystem.h"
  85 #include "llvm/Support/MemoryBuffer.h"
  86 #include "llvm/Support/SaveAndRestore.h"
  87 #include "llvm/Support/Timer.h"
  88 #include "llvm/Support/VirtualFileSystem.h"
  89 #include "llvm/Support/raw_ostream.h"
  90 #include <algorithm>
  91 #include <atomic>
  92 #include <cassert>
  93 #include <cstdint>
  94 #include <cstdio>
  95 #include <cstdlib>
  96 #include <memory>
  97 #include <mutex>
  98 #include <optional>
  99 #include <string>
 100 #include <tuple>
 101 #include <utility>
 102 #include <vector>
 103
 104 using namespace clang;
 105
 106 using llvm::TimeRecord;
 107
 108 namespace {
 109
 110   class SimpleTimer {
 111     bool WantTiming;
 112     TimeRecord Start;
 113     std::string Output;
 114
 115   public:
 116     explicit SimpleTimer(bool WantTiming) : WantTiming(WantTiming) {
 117       if (WantTiming)
 118         Start = TimeRecord::getCurrentTime();
 119     }
 120
 121     ~SimpleTimer() {
 122       if (WantTiming) {
 123         TimeRecord Elapsed = TimeRecord::getCurrentTime();
 124         Elapsed -= Start;
 125         llvm::errs() << Output << ':';
 126         Elapsed.print(Elapsed, llvm::errs());
 127         llvm::errs() << '\n';
 128       }
 129     }
 130
 131     void setOutput(const Twine &Output) {
 132       if (WantTiming)
 133         this->Output = Output.str();
 134     }
 135   };
 136
 137 } // namespace
 138
 139 template <class T>
 140 static std::unique_ptr<T> valueOrNull(llvm::ErrorOr<std::unique_ptr<T>> Val) {
 141   if (!Val)
 142     return nullptr;
 143   return std::move(*Val);
 144 }
 145
 146 template <class T>
 147 static bool moveOnNoError(llvm::ErrorOr<T> Val, T &Output) {
 148   if (!Val)
 149     return false;
 150   Output = std::move(*Val);
 151   return true;
 152 }
 153
 154 /// Get a source buffer for \p MainFilePath, handling all file-to-file
 155 /// and file-to-buffer remappings inside \p Invocation.
 156 static std::unique_ptr<llvm::MemoryBuffer>
 157 getBufferForFileHandlingRemapping(const CompilerInvocation &Invocation,
 158                                   llvm::vfs::FileSystem *VFS,
 159                                   StringRef FilePath, bool isVolatile) {
 160   const auto &PreprocessorOpts = Invocation.getPreprocessorOpts();
 161
 162   // Try to determine if the main file has been remapped, either from the
 163   // command line (to another file) or directly through the compiler
 164   // invocation (to a memory buffer).
 165   llvm::MemoryBuffer *Buffer = nullptr;
 166   std::unique_ptr<llvm::MemoryBuffer> BufferOwner;
 167   auto FileStatus = VFS->status(FilePath);
 168   if (FileStatus) {
 169     llvm::sys::fs::UniqueID MainFileID = FileStatus->getUniqueID();
 170
 171     // Check whether there is a file-file remapping of the main file
 172     for (const auto &RF : PreprocessorOpts.RemappedFiles) {
 173       std::string MPath(RF.first);
 174       auto MPathStatus = VFS->status(MPath);
 175       if (MPathStatus) {
 176         llvm::sys::fs::UniqueID MID = MPathStatus->getUniqueID();
 177         if (MainFileID == MID) {
 178           // We found a remapping. Try to load the resulting, remapped source.
 179           BufferOwner = valueOrNull(VFS->getBufferForFile(RF.second, -1, true, isVolatile));
 180           if (!BufferOwner)
 181             return nullptr;
 182         }
 183       }
 184     }
 185
 186     // Check whether there is a file-buffer remapping. It supercedes the
 187     // file-file remapping.
 188     for (const auto &RB : PreprocessorOpts.RemappedFileBuffers) {
 189       std::string MPath(RB.first);
 190       auto MPathStatus = VFS->status(MPath);
 191       if (MPathStatus) {
 192         llvm::sys::fs::UniqueID MID = MPathStatus->getUniqueID();
 193         if (MainFileID == MID) {
 194           // We found a remapping.
 195           BufferOwner.reset();
 196           Buffer = const_cast<llvm::MemoryBuffer *>(RB.second);
 197         }
 198       }
 199     }
 200   }
 201
 202   // If the main source file was not remapped, load it now.
 203   if (!Buffer && !BufferOwner) {
 204     BufferOwner = valueOrNull(VFS->getBufferForFile(FilePath, -1, true, isVolatile));
 205     if (!BufferOwner)
 206       return nullptr;
 207   }
 208
 209   if (BufferOwner)
 210     return BufferOwner;
 211   if (!Buffer)
 212     return nullptr;
 213   return llvm::MemoryBuffer::getMemBufferCopy(Buffer->getBuffer(), FilePath);
 214 }
 215
 216 struct ASTUnit::ASTWriterData {
 217   SmallString<128> Buffer;
 218   llvm::BitstreamWriter Stream;
 219   ASTWriter Writer;
 220
 221   ASTWriterData(InMemoryModuleCache &ModuleCache)
 222       : Stream(Buffer), Writer(Stream, Buffer, ModuleCache, {}) {}
 223 };
 224
 225 void ASTUnit::clearFileLevelDecls() {
 226   FileDecls.clear();
 227 }
 228
 229 /// After failing to build a precompiled preamble (due to
 230 /// errors in the source that occurs in the preamble), the number of
 231 /// reparses during which we'll skip even trying to precompile the
 232 /// preamble.
 233 const unsigned DefaultPreambleRebuildInterval = 5;
 234
 235 /// Tracks the number of ASTUnit objects that are currently active.
 236 ///
 237 /// Used for debugging purposes only.
 238 static std::atomic<unsigned> ActiveASTUnitObjects;
 239
 240 ASTUnit::ASTUnit(bool _MainFileIsAST)
 241     : MainFileIsAST(_MainFileIsAST), WantTiming(getenv("LIBCLANG_TIMING")),
 242       ShouldCacheCodeCompletionResults(false),
 243       IncludeBriefCommentsInCodeCompletion(false), UserFilesAreVolatile(false),
 244       UnsafeToFree(false) {
 245   if (getenv("LIBCLANG_OBJTRACKING"))
 246     fprintf(stderr, "+++ %u translation units\n", ++ActiveASTUnitObjects);
 247 }
 248
 249 ASTUnit::~ASTUnit() {
 250   // If we loaded from an AST file, balance out the BeginSourceFile call.
 251   if (MainFileIsAST && getDiagnostics().getClient()) {
 252     getDiagnostics().getClient()->EndSourceFile();
 253   }
 254
 255   clearFileLevelDecls();
 256
 257   // Free the buffers associated with remapped files. We are required to
 258   // perform this operation here because we explicitly request that the
 259   // compiler instance *not* free these buffers for each invocation of the
 260   // parser.
 261   if (Invocation && OwnsRemappedFileBuffers) {
 262     PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
 263     for (const auto &RB : PPOpts.RemappedFileBuffers)
 264       delete RB.second;
 265   }
 266
 267   ClearCachedCompletionResults();
 268
 269   if (getenv("LIBCLANG_OBJTRACKING"))
 270     fprintf(stderr, "--- %u translation units\n", --ActiveASTUnitObjects);
 271 }
 272
 273 void ASTUnit::setPreprocessor(std::shared_ptr<Preprocessor> PP) {
 274   this->PP = std::move(PP);
 275 }
 276
 277 void ASTUnit::enableSourceFileDiagnostics() {
 278   assert(getDiagnostics().getClient() && Ctx &&
 279       "Bad context for source file");
 280   getDiagnostics().getClient()->BeginSourceFile(Ctx->getLangOpts(), PP.get());
 281 }
 282
 283 /// Determine the set of code-completion contexts in which this
 284 /// declaration should be shown.
 285 static uint64_t getDeclShowContexts(const NamedDecl *ND,
 286                                     const LangOptions &LangOpts,
 287                                     bool &IsNestedNameSpecifier) {
 288   IsNestedNameSpecifier = false;
 289
 290   if (isa<UsingShadowDecl>(ND))
 291     ND = ND->getUnderlyingDecl();
 292   if (!ND)
 293     return 0;
 294
 295   uint64_t Contexts = 0;
 296   if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND) ||
 297       isa<ClassTemplateDecl>(ND) || isa<TemplateTemplateParmDecl>(ND) ||
 298       isa<TypeAliasTemplateDecl>(ND)) {
 299     // Types can appear in these contexts.
 300     if (LangOpts.CPlusPlus || !isa<TagDecl>(ND))
 301       Contexts |= (1LL << CodeCompletionContext::CCC_TopLevel)
 302                |  (1LL << CodeCompletionContext::CCC_ObjCIvarList)
 303                |  (1LL << CodeCompletionContext::CCC_ClassStructUnion)
 304                |  (1LL << CodeCompletionContext::CCC_Statement)
 305                |  (1LL << CodeCompletionContext::CCC_Type)
 306                |  (1LL << CodeCompletionContext::CCC_ParenthesizedExpression);
 307
 308     // In C++, types can appear in expressions contexts (for functional casts).
 309     if (LangOpts.CPlusPlus)
 310       Contexts |= (1LL << CodeCompletionContext::CCC_Expression);
 311
 312     // In Objective-C, message sends can send interfaces. In Objective-C++,
 313     // all types are available due to functional casts.
 314     if (LangOpts.CPlusPlus || isa<ObjCInterfaceDecl>(ND))
 315       Contexts |= (1LL << CodeCompletionContext::CCC_ObjCMessageReceiver);
 316
 317     // In Objective-C, you can only be a subclass of another Objective-C class
 318     if (const auto *ID = dyn_cast<ObjCInterfaceDecl>(ND)) {
 319       // Objective-C interfaces can be used in a class property expression.
 320       if (ID->getDefinition())
 321         Contexts |= (1LL << CodeCompletionContext::CCC_Expression);
 322       Contexts |= (1LL << CodeCompletionContext::CCC_ObjCInterfaceName);
 323       Contexts |= (1LL << CodeCompletionContext::CCC_ObjCClassForwardDecl);
 324     }
 325
 326     // Deal with tag names.
 327     if (isa<EnumDecl>(ND)) {
 328       Contexts |= (1LL << CodeCompletionContext::CCC_EnumTag);
 329
 330       // Part of the nested-name-specifier in C++0x.
 331       if (LangOpts.CPlusPlus11)
 332         IsNestedNameSpecifier = true;
 333     } else if (const auto *Record = dyn_cast<RecordDecl>(ND)) {
 334       if (Record->isUnion())
 335         Contexts |= (1LL << CodeCompletionContext::CCC_UnionTag);
 336       else
 337         Contexts |= (1LL << CodeCompletionContext::CCC_ClassOrStructTag);
 338
 339       if (LangOpts.CPlusPlus)
 340         IsNestedNameSpecifier = true;
 341     } else if (isa<ClassTemplateDecl>(ND))
 342       IsNestedNameSpecifier = true;
 343   } else if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) {
 344     // Values can appear in these contexts.
 345     Contexts = (1LL << CodeCompletionContext::CCC_Statement)
 346              | (1LL << CodeCompletionContext::CCC_Expression)
 347              | (1LL << CodeCompletionContext::CCC_ParenthesizedExpression)
 348              | (1LL << CodeCompletionContext::CCC_ObjCMessageReceiver);
 349   } else if (isa<ObjCProtocolDecl>(ND)) {
 350     Contexts = (1LL << CodeCompletionContext::CCC_ObjCProtocolName);
 351   } else if (isa<ObjCCategoryDecl>(ND)) {
 352     Contexts = (1LL << CodeCompletionContext::CCC_ObjCCategoryName);
 353   } else if (isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND)) {
 354     Contexts = (1LL << CodeCompletionContext::CCC_Namespace);
 355
 356     // Part of the nested-name-specifier.
 357     IsNestedNameSpecifier = true;
 358   }
 359
 360   return Contexts;
 361 }
 362
 363 void ASTUnit::CacheCodeCompletionResults() {
 364   if (!TheSema)
 365     return;
 366
 367   SimpleTimer Timer(WantTiming);
 368   Timer.setOutput("Cache global code completions for " + getMainFileName());
 369
 370   // Clear out the previous results.
 371   ClearCachedCompletionResults();
 372
 373   // Gather the set of global code completions.
 374   using Result = CodeCompletionResult;
 375   SmallVector<Result, 8> Results;
 376   CachedCompletionAllocator = std::make_shared<GlobalCodeCompletionAllocator>();
 377   CodeCompletionTUInfo CCTUInfo(CachedCompletionAllocator);
 378   TheSema->GatherGlobalCodeCompletions(*CachedCompletionAllocator,
 379                                        CCTUInfo, Results);
 380
 381   // Translate global code completions into cached completions.
 382   llvm::DenseMap<CanQualType, unsigned> CompletionTypes;
 383   CodeCompletionContext CCContext(CodeCompletionContext::CCC_TopLevel);
 384
 385   for (auto &R : Results) {
 386     switch (R.Kind) {
 387     case Result::RK_Declaration: {
 388       bool IsNestedNameSpecifier = false;
 389       CachedCodeCompletionResult CachedResult;
 390       CachedResult.Completion = R.CreateCodeCompletionString(
 391           *TheSema, CCContext, *CachedCompletionAllocator, CCTUInfo,
 392           IncludeBriefCommentsInCodeCompletion);
 393       CachedResult.ShowInContexts = getDeclShowContexts(
 394           R.Declaration, Ctx->getLangOpts(), IsNestedNameSpecifier);
 395       CachedResult.Priority = R.Priority;
 396       CachedResult.Kind = R.CursorKind;
 397       CachedResult.Availability = R.Availability;
 398
 399       // Keep track of the type of this completion in an ASTContext-agnostic
 400       // way.
 401       QualType UsageType = getDeclUsageType(*Ctx, R.Declaration);
 402       if (UsageType.isNull()) {
 403         CachedResult.TypeClass = STC_Void;
 404         CachedResult.Type = 0;
 405       } else {
 406         CanQualType CanUsageType
 407           = Ctx->getCanonicalType(UsageType.getUnqualifiedType());
 408         CachedResult.TypeClass = getSimplifiedTypeClass(CanUsageType);
 409
 410         // Determine whether we have already seen this type. If so, we save
 411         // ourselves the work of formatting the type string by using the
 412         // temporary, CanQualType-based hash table to find the associated value.
 413         unsigned &TypeValue = CompletionTypes[CanUsageType];
 414         if (TypeValue == 0) {
 415           TypeValue = CompletionTypes.size();
 416           CachedCompletionTypes[QualType(CanUsageType).getAsString()]
 417             = TypeValue;
 418         }
 419
 420         CachedResult.Type = TypeValue;
 421       }
 422
 423       CachedCompletionResults.push_back(CachedResult);
 424
 425       /// Handle nested-name-specifiers in C++.
 426       if (TheSema->Context.getLangOpts().CPlusPlus && IsNestedNameSpecifier &&
 427           !R.StartsNestedNameSpecifier) {
 428         // The contexts in which a nested-name-specifier can appear in C++.
 429         uint64_t NNSContexts
 430           = (1LL << CodeCompletionContext::CCC_TopLevel)
 431           | (1LL << CodeCompletionContext::CCC_ObjCIvarList)
 432           | (1LL << CodeCompletionContext::CCC_ClassStructUnion)
 433           | (1LL << CodeCompletionContext::CCC_Statement)
 434           | (1LL << CodeCompletionContext::CCC_Expression)
 435           | (1LL << CodeCompletionContext::CCC_ObjCMessageReceiver)
 436           | (1LL << CodeCompletionContext::CCC_EnumTag)
 437           | (1LL << CodeCompletionContext::CCC_UnionTag)
 438           | (1LL << CodeCompletionContext::CCC_ClassOrStructTag)
 439           | (1LL << CodeCompletionContext::CCC_Type)
 440           | (1LL << CodeCompletionContext::CCC_SymbolOrNewName)
 441           | (1LL << CodeCompletionContext::CCC_ParenthesizedExpression);
 442
 443         if (isa<NamespaceDecl>(R.Declaration) ||
 444             isa<NamespaceAliasDecl>(R.Declaration))
 445           NNSContexts |= (1LL << CodeCompletionContext::CCC_Namespace);
 446
 447         if (uint64_t RemainingContexts
 448                                 = NNSContexts & ~CachedResult.ShowInContexts) {
 449           // If there any contexts where this completion can be a
 450           // nested-name-specifier but isn't already an option, create a
 451           // nested-name-specifier completion.
 452           R.StartsNestedNameSpecifier = true;
 453           CachedResult.Completion = R.CreateCodeCompletionString(
 454               *TheSema, CCContext, *CachedCompletionAllocator, CCTUInfo,
 455               IncludeBriefCommentsInCodeCompletion);
 456           CachedResult.ShowInContexts = RemainingContexts;
 457           CachedResult.Priority = CCP_NestedNameSpecifier;
 458           CachedResult.TypeClass = STC_Void;
 459           CachedResult.Type = 0;
 460           CachedCompletionResults.push_back(CachedResult);
 461         }
 462       }
 463       break;
 464     }
 465
 466     case Result::RK_Keyword:
 467     case Result::RK_Pattern:
 468       // Ignore keywords and patterns; we don't care, since they are so
 469       // easily regenerated.
 470       break;
 471
 472     case Result::RK_Macro: {
 473       CachedCodeCompletionResult CachedResult;
 474       CachedResult.Completion = R.CreateCodeCompletionString(
 475           *TheSema, CCContext, *CachedCompletionAllocator, CCTUInfo,
 476           IncludeBriefCommentsInCodeCompletion);
 477       CachedResult.ShowInContexts
 478         = (1LL << CodeCompletionContext::CCC_TopLevel)
 479         | (1LL << CodeCompletionContext::CCC_ObjCInterface)
 480         | (1LL << CodeCompletionContext::CCC_ObjCImplementation)
 481         | (1LL << CodeCompletionContext::CCC_ObjCIvarList)
 482         | (1LL << CodeCompletionContext::CCC_ClassStructUnion)
 483         | (1LL << CodeCompletionContext::CCC_Statement)
 484         | (1LL << CodeCompletionContext::CCC_Expression)
 485         | (1LL << CodeCompletionContext::CCC_ObjCMessageReceiver)
 486         | (1LL << CodeCompletionContext::CCC_MacroNameUse)
 487         | (1LL << CodeCompletionContext::CCC_PreprocessorExpression)
 488         | (1LL << CodeCompletionContext::CCC_ParenthesizedExpression)
 489         | (1LL << CodeCompletionContext::CCC_OtherWithMacros);
 490
 491       CachedResult.Priority = R.Priority;
 492       CachedResult.Kind = R.CursorKind;
 493       CachedResult.Availability = R.Availability;
 494       CachedResult.TypeClass = STC_Void;
 495       CachedResult.Type = 0;
 496       CachedCompletionResults.push_back(CachedResult);
 497       break;
 498     }
 499     }
 500   }
 501
 502   // Save the current top-level hash value.
 503   CompletionCacheTopLevelHashValue = CurrentTopLevelHashValue;
 504 }
 505
 506 void ASTUnit::ClearCachedCompletionResults() {
 507   CachedCompletionResults.clear();
 508   CachedCompletionTypes.clear();
 509   CachedCompletionAllocator = nullptr;
 510 }
 511
 512 namespace {
 513
 514 /// Gathers information from ASTReader that will be used to initialize
 515 /// a Preprocessor.
 516 class ASTInfoCollector : public ASTReaderListener {
 517   Preprocessor &PP;
 518   ASTContext *Context;
 519   HeaderSearchOptions &HSOpts;
 520   PreprocessorOptions &PPOpts;
 521   LangOptions &LangOpt;
 522   std::shared_ptr<TargetOptions> &TargetOpts;
 523   IntrusiveRefCntPtr<TargetInfo> &Target;
 524   unsigned &Counter;
 525   bool InitializedLanguage = false;
 526   bool InitializedHeaderSearchPaths = false;
 527
 528 public:
 529   ASTInfoCollector(Preprocessor &PP, ASTContext *Context,
 530                    HeaderSearchOptions &HSOpts, PreprocessorOptions &PPOpts,
 531                    LangOptions &LangOpt,
 532                    std::shared_ptr<TargetOptions> &TargetOpts,
 533                    IntrusiveRefCntPtr<TargetInfo> &Target, unsigned &Counter)
 534       : PP(PP), Context(Context), HSOpts(HSOpts), PPOpts(PPOpts),
 535         LangOpt(LangOpt), TargetOpts(TargetOpts), Target(Target),
 536         Counter(Counter) {}
 537
 538   bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
 539                            bool AllowCompatibleDifferences) override {
 540     if (InitializedLanguage)
 541       return false;
 542
 543     LangOpt = LangOpts;
 544     InitializedLanguage = true;
 545
 546     updated();
 547     return false;
 548   }
 549
 550   bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
 551                                StringRef SpecificModuleCachePath,
 552                                bool Complain) override {
 553     // llvm::SaveAndRestore doesn't support bit field.
 554     auto ForceCheckCXX20ModulesInputFiles =
 555         this->HSOpts.ForceCheckCXX20ModulesInputFiles;
 556     llvm::SaveAndRestore X(this->HSOpts.UserEntries);
 557     llvm::SaveAndRestore Y(this->HSOpts.SystemHeaderPrefixes);
 558     llvm::SaveAndRestore Z(this->HSOpts.VFSOverlayFiles);
 559
 560     this->HSOpts = HSOpts;
 561     this->HSOpts.ForceCheckCXX20ModulesInputFiles =
 562         ForceCheckCXX20ModulesInputFiles;
 563
 564     return false;
 565   }
 566
 567   bool ReadHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
 568                              bool Complain) override {
 569     if (InitializedHeaderSearchPaths)
 570       return false;
 571
 572     this->HSOpts.UserEntries = HSOpts.UserEntries;
 573     this->HSOpts.SystemHeaderPrefixes = HSOpts.SystemHeaderPrefixes;
 574     this->HSOpts.VFSOverlayFiles = HSOpts.VFSOverlayFiles;
 575
 576     // Initialize the FileManager. We can't do this in update(), since that
 577     // performs the initialization too late (once both target and language
 578     // options are read).
 579     PP.getFileManager().setVirtualFileSystem(createVFSFromOverlayFiles(
 580         HSOpts.VFSOverlayFiles, PP.getDiagnostics(),
 581         PP.getFileManager().getVirtualFileSystemPtr()));
 582
 583     InitializedHeaderSearchPaths = true;
 584
 585     return false;
 586   }
 587
 588   bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
 589                                bool ReadMacros, bool Complain,
 590                                std::string &SuggestedPredefines) override {
 591     this->PPOpts = PPOpts;
 592     return false;
 593   }
 594
 595   bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
 596                          bool AllowCompatibleDifferences) override {
 597     // If we've already initialized the target, don't do it again.
 598     if (Target)
 599       return false;
 600
 601     this->TargetOpts = std::make_shared<TargetOptions>(TargetOpts);
 602     Target =
 603         TargetInfo::CreateTargetInfo(PP.getDiagnostics(), this->TargetOpts);
 604
 605     updated();
 606     return false;
 607   }
 608
 609   void ReadCounter(const serialization::ModuleFile &M,
 610                    unsigned Value) override {
 611     Counter = Value;
 612   }
 613
 614 private:
 615   void updated() {
 616     if (!Target || !InitializedLanguage)
 617       return;
 618
 619     // Inform the target of the language options.
 620     //
 621     // FIXME: We shouldn't need to do this, the target should be immutable once
 622     // created. This complexity should be lifted elsewhere.
 623     Target->adjust(PP.getDiagnostics(), LangOpt);
 624
 625     // Initialize the preprocessor.
 626     PP.Initialize(*Target);
 627
 628     if (!Context)
 629       return;
 630
 631     // Initialize the ASTContext
 632     Context->InitBuiltinTypes(*Target);
 633
 634     // Adjust printing policy based on language options.
 635     Context->setPrintingPolicy(PrintingPolicy(LangOpt));
 636
 637     // We didn't have access to the comment options when the ASTContext was
 638     // constructed, so register them now.
 639     Context->getCommentCommandTraits().registerCommentOptions(
 640         LangOpt.CommentOpts);
 641   }
 642 };
 643
 644 /// Diagnostic consumer that saves each diagnostic it is given.
 645 class FilterAndStoreDiagnosticConsumer : public DiagnosticConsumer {
 646   SmallVectorImpl<StoredDiagnostic> *StoredDiags;
 647   SmallVectorImpl<ASTUnit::StandaloneDiagnostic> *StandaloneDiags;
 648   bool CaptureNonErrorsFromIncludes = true;
 649   const LangOptions *LangOpts = nullptr;
 650   SourceManager *SourceMgr = nullptr;
 651
 652 public:
 653   FilterAndStoreDiagnosticConsumer(
 654       SmallVectorImpl<StoredDiagnostic> *StoredDiags,
 655       SmallVectorImpl<ASTUnit::StandaloneDiagnostic> *StandaloneDiags,
 656       bool CaptureNonErrorsFromIncludes)
 657       : StoredDiags(StoredDiags), StandaloneDiags(StandaloneDiags),
 658         CaptureNonErrorsFromIncludes(CaptureNonErrorsFromIncludes) {
 659     assert((StoredDiags || StandaloneDiags) &&
 660            "No output collections were passed to StoredDiagnosticConsumer.");
 661   }
 662
 663   void BeginSourceFile(const LangOptions &LangOpts,
 664                        const Preprocessor *PP = nullptr) override {
 665     this->LangOpts = &LangOpts;
 666     if (PP)
 667       SourceMgr = &PP->getSourceManager();
 668   }
 669
 670   void HandleDiagnostic(DiagnosticsEngine::Level Level,
 671                         const Diagnostic &Info) override;
 672 };
 673
 674 /// RAII object that optionally captures and filters diagnostics, if
 675 /// there is no diagnostic client to capture them already.
 676 class CaptureDroppedDiagnostics {
 677   DiagnosticsEngine &Diags;
 678   FilterAndStoreDiagnosticConsumer Client;
 679   DiagnosticConsumer *PreviousClient = nullptr;
 680   std::unique_ptr<DiagnosticConsumer> OwningPreviousClient;
 681
 682 public:
 683   CaptureDroppedDiagnostics(
 684       CaptureDiagsKind CaptureDiagnostics, DiagnosticsEngine &Diags,
 685       SmallVectorImpl<StoredDiagnostic> *StoredDiags,
 686       SmallVectorImpl<ASTUnit::StandaloneDiagnostic> *StandaloneDiags)
 687       : Diags(Diags),
 688         Client(StoredDiags, StandaloneDiags,
 689                CaptureDiagnostics !=
 690                    CaptureDiagsKind::AllWithoutNonErrorsFromIncludes) {
 691     if (CaptureDiagnostics != CaptureDiagsKind::None ||
 692         Diags.getClient() == nullptr) {
 693       OwningPreviousClient = Diags.takeClient();
 694       PreviousClient = Diags.getClient();
 695       Diags.setClient(&Client, false);
 696     }
 697   }
 698
 699   ~CaptureDroppedDiagnostics() {
 700     if (Diags.getClient() == &Client)
 701       Diags.setClient(PreviousClient, !!OwningPreviousClient.release());
 702   }
 703 };
 704
 705 } // namespace
 706
 707 static ASTUnit::StandaloneDiagnostic
 708 makeStandaloneDiagnostic(const LangOptions &LangOpts,
 709                          const StoredDiagnostic &InDiag);
 710
 711 static bool isInMainFile(const clang::Diagnostic &D) {
 712   if (!D.hasSourceManager() || !D.getLocation().isValid())
 713     return false;
 714
 715   auto &M = D.getSourceManager();
 716   return M.isWrittenInMainFile(M.getExpansionLoc(D.getLocation()));
 717 }
 718
 719 void FilterAndStoreDiagnosticConsumer::HandleDiagnostic(
 720     DiagnosticsEngine::Level Level, const Diagnostic &Info) {
 721   // Default implementation (Warnings/errors count).
 722   DiagnosticConsumer::HandleDiagnostic(Level, Info);
 723
 724   // Only record the diagnostic if it's part of the source manager we know
 725   // about. This effectively drops diagnostics from modules we're building.
 726   // FIXME: In the long run, ee don't want to drop source managers from modules.
 727   if (!Info.hasSourceManager() || &Info.getSourceManager() == SourceMgr) {
 728     if (!CaptureNonErrorsFromIncludes && Level <= DiagnosticsEngine::Warning &&
 729         !isInMainFile(Info)) {
 730       return;
 731     }
 732
 733     StoredDiagnostic *ResultDiag = nullptr;
 734     if (StoredDiags) {
 735       StoredDiags->emplace_back(Level, Info);
 736       ResultDiag = &StoredDiags->back();
 737     }
 738
 739     if (StandaloneDiags) {
 740       std::optional<StoredDiagnostic> StoredDiag;
 741       if (!ResultDiag) {
 742         StoredDiag.emplace(Level, Info);
 743         ResultDiag = &*StoredDiag;
 744       }
 745       StandaloneDiags->push_back(
 746           makeStandaloneDiagnostic(*LangOpts, *ResultDiag));
 747     }
 748   }
 749 }
 750
 751 IntrusiveRefCntPtr<ASTReader> ASTUnit::getASTReader() const {
 752   return Reader;
 753 }
 754
 755 ASTMutationListener *ASTUnit::getASTMutationListener() {
 756   if (WriterData)
 757     return &WriterData->Writer;
 758   return nullptr;
 759 }
 760
 761 ASTDeserializationListener *ASTUnit::getDeserializationListener() {
 762   if (WriterData)
 763     return &WriterData->Writer;
 764   return nullptr;
 765 }
 766
 767 std::unique_ptr<llvm::MemoryBuffer>
 768 ASTUnit::getBufferForFile(StringRef Filename, std::string *ErrorStr) {
 769   assert(FileMgr);
 770   auto Buffer = FileMgr->getBufferForFile(Filename, UserFilesAreVolatile);
 771   if (Buffer)
 772     return std::move(*Buffer);
 773   if (ErrorStr)
 774     *ErrorStr = Buffer.getError().message();
 775   return nullptr;
 776 }
 777
 778 /// Configure the diagnostics object for use with ASTUnit.
 779 void ASTUnit::ConfigureDiags(IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
 780                              ASTUnit &AST,
 781                              CaptureDiagsKind CaptureDiagnostics) {
 782   assert(Diags.get() && "no DiagnosticsEngine was provided");
 783   if (CaptureDiagnostics != CaptureDiagsKind::None)
 784     Diags->setClient(new FilterAndStoreDiagnosticConsumer(
 785         &AST.StoredDiagnostics, nullptr,
 786         CaptureDiagnostics != CaptureDiagsKind::AllWithoutNonErrorsFromIncludes));
 787 }
 788
 789 std::unique_ptr<ASTUnit> ASTUnit::LoadFromASTFile(
 790     const std::string &Filename, const PCHContainerReader &PCHContainerRdr,
 791     WhatToLoad ToLoad, IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
 792     const FileSystemOptions &FileSystemOpts,
 793     std::shared_ptr<HeaderSearchOptions> HSOpts, bool UseDebugInfo,
 794     bool OnlyLocalDecls, CaptureDiagsKind CaptureDiagnostics,
 795     bool AllowASTWithCompilerErrors, bool UserFilesAreVolatile,
 796     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
 797   std::unique_ptr<ASTUnit> AST(new ASTUnit(true));
 798
 799   // Recover resources if we crash before exiting this method.
 800   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
 801     ASTUnitCleanup(AST.get());
 802   llvm::CrashRecoveryContextCleanupRegistrar<DiagnosticsEngine,
 803     llvm::CrashRecoveryContextReleaseRefCleanup<DiagnosticsEngine>>
 804     DiagCleanup(Diags.get());
 805
 806   ConfigureDiags(Diags, *AST, CaptureDiagnostics);
 807
 808   AST->LangOpts = std::make_shared<LangOptions>();
 809   AST->OnlyLocalDecls = OnlyLocalDecls;
 810   AST->CaptureDiagnostics = CaptureDiagnostics;
 811   AST->Diagnostics = Diags;
 812   AST->FileMgr = new FileManager(FileSystemOpts, VFS);
 813   AST->UserFilesAreVolatile = UserFilesAreVolatile;
 814   AST->SourceMgr = new SourceManager(AST->getDiagnostics(),
 815                                      AST->getFileManager(),
 816                                      UserFilesAreVolatile);
 817   AST->ModuleCache = new InMemoryModuleCache;
 818   AST->HSOpts = HSOpts ? HSOpts : std::make_shared<HeaderSearchOptions>();
 819   AST->HSOpts->ModuleFormat = std::string(PCHContainerRdr.getFormats().front());
 820   AST->HeaderInfo.reset(new HeaderSearch(AST->HSOpts,
 821                                          AST->getSourceManager(),
 822                                          AST->getDiagnostics(),
 823                                          AST->getLangOpts(),
 824                                          /*Target=*/nullptr));
 825   AST->PPOpts = std::make_shared<PreprocessorOptions>();
 826
 827   // Gather Info for preprocessor construction later on.
 828
 829   HeaderSearch &HeaderInfo = *AST->HeaderInfo;
 830
 831   AST->PP = std::make_shared<Preprocessor>(
 832       AST->PPOpts, AST->getDiagnostics(), *AST->LangOpts,
 833       AST->getSourceManager(), HeaderInfo, AST->ModuleLoader,
 834       /*IILookup=*/nullptr,
 835       /*OwnsHeaderSearch=*/false);
 836   Preprocessor &PP = *AST->PP;
 837
 838   if (ToLoad >= LoadASTOnly)
 839     AST->Ctx = new ASTContext(*AST->LangOpts, AST->getSourceManager(),
 840                               PP.getIdentifierTable(), PP.getSelectorTable(),
 841                               PP.getBuiltinInfo(),
 842                               AST->getTranslationUnitKind());
 843
 844   DisableValidationForModuleKind disableValid =
 845       DisableValidationForModuleKind::None;
 846   if (::getenv("LIBCLANG_DISABLE_PCH_VALIDATION"))
 847     disableValid = DisableValidationForModuleKind::All;
 848   AST->Reader = new ASTReader(
 849       PP, *AST->ModuleCache, AST->Ctx.get(), PCHContainerRdr, {},
 850       /*isysroot=*/"",
 851       /*DisableValidationKind=*/disableValid, AllowASTWithCompilerErrors);
 852
 853   unsigned Counter = 0;
 854   AST->Reader->setListener(std::make_unique<ASTInfoCollector>(
 855       *AST->PP, AST->Ctx.get(), *AST->HSOpts, *AST->PPOpts, *AST->LangOpts,
 856       AST->TargetOpts, AST->Target, Counter));
 857
 858   // Attach the AST reader to the AST context as an external AST
 859   // source, so that declarations will be deserialized from the
 860   // AST file as needed.
 861   // We need the external source to be set up before we read the AST, because
 862   // eagerly-deserialized declarations may use it.
 863   if (AST->Ctx)
 864     AST->Ctx->setExternalSource(AST->Reader);
 865
 866   switch (AST->Reader->ReadAST(Filename, serialization::MK_MainFile,
 867                                SourceLocation(), ASTReader::ARR_None)) {
 868   case ASTReader::Success:
 869     break;
 870
 871   case ASTReader::Failure:
 872   case ASTReader::Missing:
 873   case ASTReader::OutOfDate:
 874   case ASTReader::VersionMismatch:
 875   case ASTReader::ConfigurationMismatch:
 876   case ASTReader::HadErrors:
 877     AST->getDiagnostics().Report(diag::err_fe_unable_to_load_pch);
 878     return nullptr;
 879   }
 880
 881   AST->OriginalSourceFile = std::string(AST->Reader->getOriginalSourceFile());
 882
 883   PP.setCounterValue(Counter);
 884
 885   Module *M = HeaderInfo.lookupModule(AST->getLangOpts().CurrentModule);
 886   if (M && AST->getLangOpts().isCompilingModule() && M->isModulePurview())
 887     AST->Ctx->setCurrentNamedModule(M);
 888
 889   // Create an AST consumer, even though it isn't used.
 890   if (ToLoad >= LoadASTOnly)
 891     AST->Consumer.reset(new ASTConsumer);
 892
 893   // Create a semantic analysis object and tell the AST reader about it.
 894   if (ToLoad >= LoadEverything) {
 895     AST->TheSema.reset(new Sema(PP, *AST->Ctx, *AST->Consumer));
 896     AST->TheSema->Initialize();
 897     AST->Reader->InitializeSema(*AST->TheSema);
 898   }
 899
 900   // Tell the diagnostic client that we have started a source file.
 901   AST->getDiagnostics().getClient()->BeginSourceFile(PP.getLangOpts(), &PP);
 902
 903   return AST;
 904 }
 905
 906 /// Add the given macro to the hash of all top-level entities.
 907 static void AddDefinedMacroToHash(const Token &MacroNameTok, unsigned &Hash) {
 908   Hash = llvm::djbHash(MacroNameTok.getIdentifierInfo()->getName(), Hash);
 909 }
 910
 911 namespace {
 912
 913 /// Preprocessor callback class that updates a hash value with the names
 914 /// of all macros that have been defined by the translation unit.
 915 class MacroDefinitionTrackerPPCallbacks : public PPCallbacks {
 916   unsigned &Hash;
 917
 918 public:
 919   explicit MacroDefinitionTrackerPPCallbacks(unsigned &Hash) : Hash(Hash) {}
 920
 921   void MacroDefined(const Token &MacroNameTok,
 922                     const MacroDirective *MD) override {
 923     AddDefinedMacroToHash(MacroNameTok, Hash);
 924   }
 925 };
 926
 927 } // namespace
 928
 929 /// Add the given declaration to the hash of all top-level entities.
 930 static void AddTopLevelDeclarationToHash(Decl *D, unsigned &Hash) {
 931   if (!D)
 932     return;
 933
 934   DeclContext *DC = D->getDeclContext();
 935   if (!DC)
 936     return;
 937
 938   if (!(DC->isTranslationUnit() || DC->getLookupParent()->isTranslationUnit()))
 939     return;
 940
 941   if (const auto *ND = dyn_cast<NamedDecl>(D)) {
 942     if (const auto *EnumD = dyn_cast<EnumDecl>(D)) {
 943       // For an unscoped enum include the enumerators in the hash since they
 944       // enter the top-level namespace.
 945       if (!EnumD->isScoped()) {
 946         for (const auto *EI : EnumD->enumerators()) {
 947           if (EI->getIdentifier())
 948             Hash = llvm::djbHash(EI->getIdentifier()->getName(), Hash);
 949         }
 950       }
 951     }
 952
 953     if (ND->getIdentifier())
 954       Hash = llvm::djbHash(ND->getIdentifier()->getName(), Hash);
 955     else if (DeclarationName Name = ND->getDeclName()) {
 956       std::string NameStr = Name.getAsString();
 957       Hash = llvm::djbHash(NameStr, Hash);
 958     }
 959     return;
 960   }
 961
 962   if (const auto *ImportD = dyn_cast<ImportDecl>(D)) {
 963     if (const Module *Mod = ImportD->getImportedModule()) {
 964       std::string ModName = Mod->getFullModuleName();
 965       Hash = llvm::djbHash(ModName, Hash);
 966     }
 967     return;
 968   }
 969 }
 970
 971 namespace {
 972
 973 class TopLevelDeclTrackerConsumer : public ASTConsumer {
 974   ASTUnit &Unit;
 975   unsigned &Hash;
 976
 977 public:
 978   TopLevelDeclTrackerConsumer(ASTUnit &_Unit, unsigned &Hash)
 979       : Unit(_Unit), Hash(Hash) {
 980     Hash = 0;
 981   }
 982
 983   void handleTopLevelDecl(Decl *D) {
 984     if (!D)
 985       return;
 986
 987     // FIXME: Currently ObjC method declarations are incorrectly being
 988     // reported as top-level declarations, even though their DeclContext
 989     // is the containing ObjC @interface/@implementation.  This is a
 990     // fundamental problem in the parser right now.
 991     if (isa<ObjCMethodDecl>(D))
 992       return;
 993
 994     AddTopLevelDeclarationToHash(D, Hash);
 995     Unit.addTopLevelDecl(D);
 996
 997     handleFileLevelDecl(D);
 998   }
 999
1000   void handleFileLevelDecl(Decl *D) {
1001     Unit.addFileLevelDecl(D);
1002     if (auto *NSD = dyn_cast<NamespaceDecl>(D)) {
1003       for (auto *I : NSD->decls())
1004         handleFileLevelDecl(I);
1005     }
1006   }
1007
1008   bool HandleTopLevelDecl(DeclGroupRef D) override {
1009     for (auto *TopLevelDecl : D)
1010       handleTopLevelDecl(TopLevelDecl);
1011     return true;
1012   }
1013
1014   // We're not interested in "interesting" decls.
1015   void HandleInterestingDecl(DeclGroupRef) override {}
1016
1017   void HandleTopLevelDeclInObjCContainer(DeclGroupRef D) override {
1018     for (auto *TopLevelDecl : D)
1019       handleTopLevelDecl(TopLevelDecl);
1020   }
1021
1022   ASTMutationListener *GetASTMutationListener() override {
1023     return Unit.getASTMutationListener();
1024   }
1025
1026   ASTDeserializationListener *GetASTDeserializationListener() override {
1027     return Unit.getDeserializationListener();
1028   }
1029 };
1030
1031 class TopLevelDeclTrackerAction : public ASTFrontendAction {
1032 public:
1033   ASTUnit &Unit;
1034
1035   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
1036                                                  StringRef InFile) override {
1037     CI.getPreprocessor().addPPCallbacks(
1038         std::make_unique<MacroDefinitionTrackerPPCallbacks>(
1039                                            Unit.getCurrentTopLevelHashValue()));
1040     return std::make_unique<TopLevelDeclTrackerConsumer>(
1041         Unit, Unit.getCurrentTopLevelHashValue());
1042   }
1043
1044 public:
1045   TopLevelDeclTrackerAction(ASTUnit &_Unit) : Unit(_Unit) {}
1046
1047   bool hasCodeCompletionSupport() const override { return false; }
1048
1049   TranslationUnitKind getTranslationUnitKind() override {
1050     return Unit.getTranslationUnitKind();
1051   }
1052 };
1053
1054 class ASTUnitPreambleCallbacks : public PreambleCallbacks {
1055 public:
1056   unsigned getHash() const { return Hash; }
1057
1058   std::vector<Decl *> takeTopLevelDecls() { return std::move(TopLevelDecls); }
1059
1060   std::vector<serialization::DeclID> takeTopLevelDeclIDs() {
1061     return std::move(TopLevelDeclIDs);
1062   }
1063
1064   void AfterPCHEmitted(ASTWriter &Writer) override {
1065     TopLevelDeclIDs.reserve(TopLevelDecls.size());
1066     for (const auto *D : TopLevelDecls) {
1067       // Invalid top-level decls may not have been serialized.
1068       if (D->isInvalidDecl())
1069         continue;
1070       TopLevelDeclIDs.push_back(Writer.getDeclID(D));
1071     }
1072   }
1073
1074   void HandleTopLevelDecl(DeclGroupRef DG) override {
1075     for (auto *D : DG) {
1076       // FIXME: Currently ObjC method declarations are incorrectly being
1077       // reported as top-level declarations, even though their DeclContext
1078       // is the containing ObjC @interface/@implementation.  This is a
1079       // fundamental problem in the parser right now.
1080       if (isa<ObjCMethodDecl>(D))
1081         continue;
1082       AddTopLevelDeclarationToHash(D, Hash);
1083       TopLevelDecls.push_back(D);
1084     }
1085   }
1086
1087   std::unique_ptr<PPCallbacks> createPPCallbacks() override {
1088     return std::make_unique<MacroDefinitionTrackerPPCallbacks>(Hash);
1089   }
1090
1091 private:
1092   unsigned Hash = 0;
1093   std::vector<Decl *> TopLevelDecls;
1094   std::vector<serialization::DeclID> TopLevelDeclIDs;
1095   llvm::SmallVector<ASTUnit::StandaloneDiagnostic, 4> PreambleDiags;
1096 };
1097
1098 } // namespace
1099
1100 static bool isNonDriverDiag(const StoredDiagnostic &StoredDiag) {
1101   return StoredDiag.getLocation().isValid();
1102 }
1103
1104 static void
1105 checkAndRemoveNonDriverDiags(SmallVectorImpl<StoredDiagnostic> &StoredDiags) {
1106   // Get rid of stored diagnostics except the ones from the driver which do not
1107   // have a source location.
1108   llvm::erase_if(StoredDiags, isNonDriverDiag);
1109 }
1110
1111 static void checkAndSanitizeDiags(SmallVectorImpl<StoredDiagnostic> &
1112                                                               StoredDiagnostics,
1113                                   SourceManager &SM) {
1114   // The stored diagnostic has the old source manager in it; update
1115   // the locations to refer into the new source manager. Since we've
1116   // been careful to make sure that the source manager's state
1117   // before and after are identical, so that we can reuse the source
1118   // location itself.
1119   for (auto &SD : StoredDiagnostics) {
1120     if (SD.getLocation().isValid()) {
1121       FullSourceLoc Loc(SD.getLocation(), SM);
1122       SD.setLocation(Loc);
1123     }
1124   }
1125 }
1126
1127 /// Parse the source file into a translation unit using the given compiler
1128 /// invocation, replacing the current translation unit.
1129 ///
1130 /// \returns True if a failure occurred that causes the ASTUnit not to
1131 /// contain any translation-unit information, false otherwise.
1132 bool ASTUnit::Parse(std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1133                     std::unique_ptr<llvm::MemoryBuffer> OverrideMainBuffer,
1134                     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
1135   if (!Invocation)
1136     return true;
1137
1138   if (VFS && FileMgr)
1139     assert(VFS == &FileMgr->getVirtualFileSystem() &&
1140            "VFS passed to Parse and VFS in FileMgr are different");
1141
1142   auto CCInvocation = std::make_shared<CompilerInvocation>(*Invocation);
1143   if (OverrideMainBuffer) {
1144     assert(Preamble &&
1145            "No preamble was built, but OverrideMainBuffer is not null");
1146     Preamble->AddImplicitPreamble(*CCInvocation, VFS, OverrideMainBuffer.get());
1147     // VFS may have changed...
1148   }
1149
1150   // Create the compiler instance to use for building the AST.
1151   std::unique_ptr<CompilerInstance> Clang(
1152       new CompilerInstance(std::move(PCHContainerOps)));
1153   Clang->setInvocation(CCInvocation);
1154
1155   // Clean up on error, disengage it if the function returns successfully.
1156   auto CleanOnError = llvm::make_scope_exit([&]() {
1157     // Remove the overridden buffer we used for the preamble.
1158     SavedMainFileBuffer = nullptr;
1159
1160     // Keep the ownership of the data in the ASTUnit because the client may
1161     // want to see the diagnostics.
1162     transferASTDataFromCompilerInstance(*Clang);
1163     FailedParseDiagnostics.swap(StoredDiagnostics);
1164     StoredDiagnostics.clear();
1165     NumStoredDiagnosticsFromDriver = 0;
1166   });
1167
1168   // Ensure that Clang has a FileManager with the right VFS, which may have
1169   // changed above in AddImplicitPreamble.  If VFS is nullptr, rely on
1170   // createFileManager to create one.
1171   if (VFS && FileMgr && &FileMgr->getVirtualFileSystem() == VFS)
1172     Clang->setFileManager(&*FileMgr);
1173   else
1174     FileMgr = Clang->createFileManager(std::move(VFS));
1175
1176   // Recover resources if we crash before exiting this method.
1177   llvm::CrashRecoveryContextCleanupRegistrar<CompilerInstance>
1178     CICleanup(Clang.get());
1179
1180   OriginalSourceFile =
1181       std::string(Clang->getFrontendOpts().Inputs[0].getFile());
1182
1183   // Set up diagnostics, capturing any diagnostics that would
1184   // otherwise be dropped.
1185   Clang->setDiagnostics(&getDiagnostics());
1186
1187   // Create the target instance.
1188   if (!Clang->createTarget())
1189     return true;
1190
1191   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
1192          "Invocation must have exactly one source file!");
1193   assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
1194              InputKind::Source &&
1195          "FIXME: AST inputs not yet supported here!");
1196   assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
1197              Language::LLVM_IR &&
1198          "IR inputs not support here!");
1199
1200   // Configure the various subsystems.
1201   LangOpts = Clang->getInvocation().LangOpts;
1202   FileSystemOpts = Clang->getFileSystemOpts();
1203
1204   ResetForParse();
1205
1206   SourceMgr = new SourceManager(getDiagnostics(), *FileMgr,
1207                                 UserFilesAreVolatile);
1208   if (!OverrideMainBuffer) {
1209     checkAndRemoveNonDriverDiags(StoredDiagnostics);
1210     TopLevelDeclsInPreamble.clear();
1211   }
1212
1213   // Create the source manager.
1214   Clang->setSourceManager(&getSourceManager());
1215
1216   // If the main file has been overridden due to the use of a preamble,
1217   // make that override happen and introduce the preamble.
1218   if (OverrideMainBuffer) {
1219     // The stored diagnostic has the old source manager in it; update
1220     // the locations to refer into the new source manager. Since we've
1221     // been careful to make sure that the source manager's state
1222     // before and after are identical, so that we can reuse the source
1223     // location itself.
1224     checkAndSanitizeDiags(StoredDiagnostics, getSourceManager());
1225
1226     // Keep track of the override buffer;
1227     SavedMainFileBuffer = std::move(OverrideMainBuffer);
1228   }
1229
1230   std::unique_ptr<TopLevelDeclTrackerAction> Act(
1231       new TopLevelDeclTrackerAction(*this));
1232
1233   // Recover resources if we crash before exiting this method.
1234   llvm::CrashRecoveryContextCleanupRegistrar<TopLevelDeclTrackerAction>
1235     ActCleanup(Act.get());
1236
1237   if (!Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0]))
1238     return true;
1239
1240   if (SavedMainFileBuffer)
1241     TranslateStoredDiagnostics(getFileManager(), getSourceManager(),
1242                                PreambleDiagnostics, StoredDiagnostics);
1243   else
1244     PreambleSrcLocCache.clear();
1245
1246   if (llvm::Error Err = Act->Execute()) {
1247     consumeError(std::move(Err)); // FIXME this drops errors on the floor.
1248     return true;
1249   }
1250
1251   transferASTDataFromCompilerInstance(*Clang);
1252
1253   Act->EndSourceFile();
1254
1255   FailedParseDiagnostics.clear();
1256
1257   CleanOnError.release();
1258
1259   return false;
1260 }
1261
1262 static std::pair<unsigned, unsigned>
1263 makeStandaloneRange(CharSourceRange Range, const SourceManager &SM,
1264                     const LangOptions &LangOpts) {
1265   CharSourceRange FileRange = Lexer::makeFileCharRange(Range, SM, LangOpts);
1266   unsigned Offset = SM.getFileOffset(FileRange.getBegin());
1267   unsigned EndOffset = SM.getFileOffset(FileRange.getEnd());
1268   return std::make_pair(Offset, EndOffset);
1269 }
1270
1271 static ASTUnit::StandaloneFixIt makeStandaloneFixIt(const SourceManager &SM,
1272                                                     const LangOptions &LangOpts,
1273                                                     const FixItHint &InFix) {
1274   ASTUnit::StandaloneFixIt OutFix;
1275   OutFix.RemoveRange = makeStandaloneRange(InFix.RemoveRange, SM, LangOpts);
1276   OutFix.InsertFromRange = makeStandaloneRange(InFix.InsertFromRange, SM,
1277                                                LangOpts);
1278   OutFix.CodeToInsert = InFix.CodeToInsert;
1279   OutFix.BeforePreviousInsertions = InFix.BeforePreviousInsertions;
1280   return OutFix;
1281 }
1282
1283 static ASTUnit::StandaloneDiagnostic
1284 makeStandaloneDiagnostic(const LangOptions &LangOpts,
1285                          const StoredDiagnostic &InDiag) {
1286   ASTUnit::StandaloneDiagnostic OutDiag;
1287   OutDiag.ID = InDiag.getID();
1288   OutDiag.Level = InDiag.getLevel();
1289   OutDiag.Message = std::string(InDiag.getMessage());
1290   OutDiag.LocOffset = 0;
1291   if (InDiag.getLocation().isInvalid())
1292     return OutDiag;
1293   const SourceManager &SM = InDiag.getLocation().getManager();
1294   SourceLocation FileLoc = SM.getFileLoc(InDiag.getLocation());
1295   OutDiag.Filename = std::string(SM.getFilename(FileLoc));
1296   if (OutDiag.Filename.empty())
1297     return OutDiag;
1298   OutDiag.LocOffset = SM.getFileOffset(FileLoc);
1299   for (const auto &Range : InDiag.getRanges())
1300     OutDiag.Ranges.push_back(makeStandaloneRange(Range, SM, LangOpts));
1301   for (const auto &FixIt : InDiag.getFixIts())
1302     OutDiag.FixIts.push_back(makeStandaloneFixIt(SM, LangOpts, FixIt));
1303
1304   return OutDiag;
1305 }
1306
1307 /// Attempt to build or re-use a precompiled preamble when (re-)parsing
1308 /// the source file.
1309 ///
1310 /// This routine will compute the preamble of the main source file. If a
1311 /// non-trivial preamble is found, it will precompile that preamble into a
1312 /// precompiled header so that the precompiled preamble can be used to reduce
1313 /// reparsing time. If a precompiled preamble has already been constructed,
1314 /// this routine will determine if it is still valid and, if so, avoid
1315 /// rebuilding the precompiled preamble.
1316 ///
1317 /// \param AllowRebuild When true (the default), this routine is
1318 /// allowed to rebuild the precompiled preamble if it is found to be
1319 /// out-of-date.
1320 ///
1321 /// \param MaxLines When non-zero, the maximum number of lines that
1322 /// can occur within the preamble.
1323 ///
1324 /// \returns If the precompiled preamble can be used, returns a newly-allocated
1325 /// buffer that should be used in place of the main file when doing so.
1326 /// Otherwise, returns a NULL pointer.
1327 std::unique_ptr<llvm::MemoryBuffer>
1328 ASTUnit::getMainBufferWithPrecompiledPreamble(
1329     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1330     CompilerInvocation &PreambleInvocationIn,
1331     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS, bool AllowRebuild,
1332     unsigned MaxLines) {
1333   auto MainFilePath =
1334       PreambleInvocationIn.getFrontendOpts().Inputs[0].getFile();
1335   std::unique_ptr<llvm::MemoryBuffer> MainFileBuffer =
1336       getBufferForFileHandlingRemapping(PreambleInvocationIn, VFS.get(),
1337                                         MainFilePath, UserFilesAreVolatile);
1338   if (!MainFileBuffer)
1339     return nullptr;
1340
1341   PreambleBounds Bounds = ComputePreambleBounds(
1342       PreambleInvocationIn.getLangOpts(), *MainFileBuffer, MaxLines);
1343   if (!Bounds.Size)
1344     return nullptr;
1345
1346   if (Preamble) {
1347     if (Preamble->CanReuse(PreambleInvocationIn, *MainFileBuffer, Bounds,
1348                            *VFS)) {
1349       // Okay! We can re-use the precompiled preamble.
1350
1351       // Set the state of the diagnostic object to mimic its state
1352       // after parsing the preamble.
1353       getDiagnostics().Reset();
1354       ProcessWarningOptions(getDiagnostics(),
1355                             PreambleInvocationIn.getDiagnosticOpts());
1356       getDiagnostics().setNumWarnings(NumWarningsInPreamble);
1357
1358       PreambleRebuildCountdown = 1;
1359       return MainFileBuffer;
1360     } else {
1361       Preamble.reset();
1362       PreambleDiagnostics.clear();
1363       TopLevelDeclsInPreamble.clear();
1364       PreambleSrcLocCache.clear();
1365       PreambleRebuildCountdown = 1;
1366     }
1367   }
1368
1369   // If the preamble rebuild counter > 1, it's because we previously
1370   // failed to build a preamble and we're not yet ready to try
1371   // again. Decrement the counter and return a failure.
1372   if (PreambleRebuildCountdown > 1) {
1373     --PreambleRebuildCountdown;
1374     return nullptr;
1375   }
1376
1377   assert(!Preamble && "No Preamble should be stored at that point");
1378   // If we aren't allowed to rebuild the precompiled preamble, just
1379   // return now.
1380   if (!AllowRebuild)
1381     return nullptr;
1382
1383   ++PreambleCounter;
1384
1385   SmallVector<StandaloneDiagnostic, 4> NewPreambleDiagsStandalone;
1386   SmallVector<StoredDiagnostic, 4> NewPreambleDiags;
1387   ASTUnitPreambleCallbacks Callbacks;
1388   {
1389     std::optional<CaptureDroppedDiagnostics> Capture;
1390     if (CaptureDiagnostics != CaptureDiagsKind::None)
1391       Capture.emplace(CaptureDiagnostics, *Diagnostics, &NewPreambleDiags,
1392                       &NewPreambleDiagsStandalone);
1393
1394     // We did not previously compute a preamble, or it can't be reused anyway.
1395     SimpleTimer PreambleTimer(WantTiming);
1396     PreambleTimer.setOutput("Precompiling preamble");
1397
1398     const bool PreviousSkipFunctionBodies =
1399         PreambleInvocationIn.getFrontendOpts().SkipFunctionBodies;
1400     if (SkipFunctionBodies == SkipFunctionBodiesScope::Preamble)
1401       PreambleInvocationIn.getFrontendOpts().SkipFunctionBodies = true;
1402
1403     llvm::ErrorOr<PrecompiledPreamble> NewPreamble = PrecompiledPreamble::Build(
1404         PreambleInvocationIn, MainFileBuffer.get(), Bounds, *Diagnostics, VFS,
1405         PCHContainerOps, StorePreamblesInMemory, PreambleStoragePath,
1406         Callbacks);
1407
1408     PreambleInvocationIn.getFrontendOpts().SkipFunctionBodies =
1409         PreviousSkipFunctionBodies;
1410
1411     if (NewPreamble) {
1412       Preamble = std::move(*NewPreamble);
1413       PreambleRebuildCountdown = 1;
1414     } else {
1415       switch (static_cast<BuildPreambleError>(NewPreamble.getError().value())) {
1416       case BuildPreambleError::CouldntCreateTempFile:
1417         // Try again next time.
1418         PreambleRebuildCountdown = 1;
1419         return nullptr;
1420       case BuildPreambleError::CouldntCreateTargetInfo:
1421       case BuildPreambleError::BeginSourceFileFailed:
1422       case BuildPreambleError::CouldntEmitPCH:
1423       case BuildPreambleError::BadInputs:
1424         // These erros are more likely to repeat, retry after some period.
1425         PreambleRebuildCountdown = DefaultPreambleRebuildInterval;
1426         return nullptr;
1427       }
1428       llvm_unreachable("unexpected BuildPreambleError");
1429     }
1430   }
1431
1432   assert(Preamble && "Preamble wasn't built");
1433
1434   TopLevelDecls.clear();
1435   TopLevelDeclsInPreamble = Callbacks.takeTopLevelDeclIDs();
1436   PreambleTopLevelHashValue = Callbacks.getHash();
1437
1438   NumWarningsInPreamble = getDiagnostics().getNumWarnings();
1439
1440   checkAndRemoveNonDriverDiags(NewPreambleDiags);
1441   StoredDiagnostics = std::move(NewPreambleDiags);
1442   PreambleDiagnostics = std::move(NewPreambleDiagsStandalone);
1443
1444   // If the hash of top-level entities differs from the hash of the top-level
1445   // entities the last time we rebuilt the preamble, clear out the completion
1446   // cache.
1447   if (CurrentTopLevelHashValue != PreambleTopLevelHashValue) {
1448     CompletionCacheTopLevelHashValue = 0;
1449     PreambleTopLevelHashValue = CurrentTopLevelHashValue;
1450   }
1451
1452   return MainFileBuffer;
1453 }
1454
1455 void ASTUnit::RealizeTopLevelDeclsFromPreamble() {
1456   assert(Preamble && "Should only be called when preamble was built");
1457
1458   std::vector<Decl *> Resolved;
1459   Resolved.reserve(TopLevelDeclsInPreamble.size());
1460   ExternalASTSource &Source = *getASTContext().getExternalSource();
1461   for (const auto TopLevelDecl : TopLevelDeclsInPreamble) {
1462     // Resolve the declaration ID to an actual declaration, possibly
1463     // deserializing the declaration in the process.
1464     if (Decl *D = Source.GetExternalDecl(TopLevelDecl))
1465       Resolved.push_back(D);
1466   }
1467   TopLevelDeclsInPreamble.clear();
1468   TopLevelDecls.insert(TopLevelDecls.begin(), Resolved.begin(), Resolved.end());
1469 }
1470
1471 void ASTUnit::transferASTDataFromCompilerInstance(CompilerInstance &CI) {
1472   // Steal the created target, context, and preprocessor if they have been
1473   // created.
1474   assert(CI.hasInvocation() && "missing invocation");
1475   LangOpts = CI.getInvocation().LangOpts;
1476   TheSema = CI.takeSema();
1477   Consumer = CI.takeASTConsumer();
1478   if (CI.hasASTContext())
1479     Ctx = &CI.getASTContext();
1480   if (CI.hasPreprocessor())
1481     PP = CI.getPreprocessorPtr();
1482   CI.setSourceManager(nullptr);
1483   CI.setFileManager(nullptr);
1484   if (CI.hasTarget())
1485     Target = &CI.getTarget();
1486   Reader = CI.getASTReader();
1487   HadModuleLoaderFatalFailure = CI.hadModuleLoaderFatalFailure();
1488 }
1489
1490 StringRef ASTUnit::getMainFileName() const {
1491   if (Invocation && !Invocation->getFrontendOpts().Inputs.empty()) {
1492     const FrontendInputFile &Input = Invocation->getFrontendOpts().Inputs[0];
1493     if (Input.isFile())
1494       return Input.getFile();
1495     else
1496       return Input.getBuffer().getBufferIdentifier();
1497   }
1498
1499   if (SourceMgr) {
1500     if (OptionalFileEntryRef FE =
1501             SourceMgr->getFileEntryRefForID(SourceMgr->getMainFileID()))
1502       return FE->getName();
1503   }
1504
1505   return {};
1506 }
1507
1508 StringRef ASTUnit::getASTFileName() const {
1509   if (!isMainFileAST())
1510     return {};
1511
1512   serialization::ModuleFile &
1513     Mod = Reader->getModuleManager().getPrimaryModule();
1514   return Mod.FileName;
1515 }
1516
1517 std::unique_ptr<ASTUnit>
1518 ASTUnit::create(std::shared_ptr<CompilerInvocation> CI,
1519                 IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
1520                 CaptureDiagsKind CaptureDiagnostics,
1521                 bool UserFilesAreVolatile) {
1522   std::unique_ptr<ASTUnit> AST(new ASTUnit(false));
1523   ConfigureDiags(Diags, *AST, CaptureDiagnostics);
1524   IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
1525       createVFSFromCompilerInvocation(*CI, *Diags);
1526   AST->Diagnostics = Diags;
1527   AST->FileSystemOpts = CI->getFileSystemOpts();
1528   AST->Invocation = std::move(CI);
1529   AST->FileMgr = new FileManager(AST->FileSystemOpts, VFS);
1530   AST->UserFilesAreVolatile = UserFilesAreVolatile;
1531   AST->SourceMgr = new SourceManager(AST->getDiagnostics(), *AST->FileMgr,
1532                                      UserFilesAreVolatile);
1533   AST->ModuleCache = new InMemoryModuleCache;
1534
1535   return AST;
1536 }
1537
1538 ASTUnit *ASTUnit::LoadFromCompilerInvocationAction(
1539     std::shared_ptr<CompilerInvocation> CI,
1540     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1541     IntrusiveRefCntPtr<DiagnosticsEngine> Diags, FrontendAction *Action,
1542     ASTUnit *Unit, bool Persistent, StringRef ResourceFilesPath,
1543     bool OnlyLocalDecls, CaptureDiagsKind CaptureDiagnostics,
1544     unsigned PrecompilePreambleAfterNParses, bool CacheCodeCompletionResults,
1545     bool UserFilesAreVolatile, std::unique_ptr<ASTUnit> *ErrAST) {
1546   assert(CI && "A CompilerInvocation is required");
1547
1548   std::unique_ptr<ASTUnit> OwnAST;
1549   ASTUnit *AST = Unit;
1550   if (!AST) {
1551     // Create the AST unit.
1552     OwnAST = create(CI, Diags, CaptureDiagnostics, UserFilesAreVolatile);
1553     AST = OwnAST.get();
1554     if (!AST)
1555       return nullptr;
1556   }
1557
1558   if (!ResourceFilesPath.empty()) {
1559     // Override the resources path.
1560     CI->getHeaderSearchOpts().ResourceDir = std::string(ResourceFilesPath);
1561   }
1562   AST->OnlyLocalDecls = OnlyLocalDecls;
1563   AST->CaptureDiagnostics = CaptureDiagnostics;
1564   if (PrecompilePreambleAfterNParses > 0)
1565     AST->PreambleRebuildCountdown = PrecompilePreambleAfterNParses;
1566   AST->TUKind = Action ? Action->getTranslationUnitKind() : TU_Complete;
1567   AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1568   AST->IncludeBriefCommentsInCodeCompletion = false;
1569
1570   // Recover resources if we crash before exiting this method.
1571   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
1572     ASTUnitCleanup(OwnAST.get());
1573   llvm::CrashRecoveryContextCleanupRegistrar<DiagnosticsEngine,
1574     llvm::CrashRecoveryContextReleaseRefCleanup<DiagnosticsEngine>>
1575     DiagCleanup(Diags.get());
1576
1577   // We'll manage file buffers ourselves.
1578   CI->getPreprocessorOpts().RetainRemappedFileBuffers = true;
1579   CI->getFrontendOpts().DisableFree = false;
1580   ProcessWarningOptions(AST->getDiagnostics(), CI->getDiagnosticOpts());
1581
1582   // Create the compiler instance to use for building the AST.
1583   std::unique_ptr<CompilerInstance> Clang(
1584       new CompilerInstance(std::move(PCHContainerOps)));
1585
1586   // Recover resources if we crash before exiting this method.
1587   llvm::CrashRecoveryContextCleanupRegistrar<CompilerInstance>
1588     CICleanup(Clang.get());
1589
1590   Clang->setInvocation(std::move(CI));
1591   AST->OriginalSourceFile =
1592       std::string(Clang->getFrontendOpts().Inputs[0].getFile());
1593
1594   // Set up diagnostics, capturing any diagnostics that would
1595   // otherwise be dropped.
1596   Clang->setDiagnostics(&AST->getDiagnostics());
1597
1598   // Create the target instance.
1599   if (!Clang->createTarget())
1600     return nullptr;
1601
1602   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
1603          "Invocation must have exactly one source file!");
1604   assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
1605              InputKind::Source &&
1606          "FIXME: AST inputs not yet supported here!");
1607   assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
1608              Language::LLVM_IR &&
1609          "IR inputs not support here!");
1610
1611   // Configure the various subsystems.
1612   AST->TheSema.reset();
1613   AST->Ctx = nullptr;
1614   AST->PP = nullptr;
1615   AST->Reader = nullptr;
1616
1617   // Create a file manager object to provide access to and cache the filesystem.
1618   Clang->setFileManager(&AST->getFileManager());
1619
1620   // Create the source manager.
1621   Clang->setSourceManager(&AST->getSourceManager());
1622
1623   FrontendAction *Act = Action;
1624
1625   std::unique_ptr<TopLevelDeclTrackerAction> TrackerAct;
1626   if (!Act) {
1627     TrackerAct.reset(new TopLevelDeclTrackerAction(*AST));
1628     Act = TrackerAct.get();
1629   }
1630
1631   // Recover resources if we crash before exiting this method.
1632   llvm::CrashRecoveryContextCleanupRegistrar<TopLevelDeclTrackerAction>
1633     ActCleanup(TrackerAct.get());
1634
1635   if (!Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0])) {
1636     AST->transferASTDataFromCompilerInstance(*Clang);
1637     if (OwnAST && ErrAST)
1638       ErrAST->swap(OwnAST);
1639
1640     return nullptr;
1641   }
1642
1643   if (Persistent && !TrackerAct) {
1644     Clang->getPreprocessor().addPPCallbacks(
1645         std::make_unique<MacroDefinitionTrackerPPCallbacks>(
1646                                            AST->getCurrentTopLevelHashValue()));
1647     std::vector<std::unique_ptr<ASTConsumer>> Consumers;
1648     if (Clang->hasASTConsumer())
1649       Consumers.push_back(Clang->takeASTConsumer());
1650     Consumers.push_back(std::make_unique<TopLevelDeclTrackerConsumer>(
1651         *AST, AST->getCurrentTopLevelHashValue()));
1652     Clang->setASTConsumer(
1653         std::make_unique<MultiplexConsumer>(std::move(Consumers)));
1654   }
1655   if (llvm::Error Err = Act->Execute()) {
1656     consumeError(std::move(Err)); // FIXME this drops errors on the floor.
1657     AST->transferASTDataFromCompilerInstance(*Clang);
1658     if (OwnAST && ErrAST)
1659       ErrAST->swap(OwnAST);
1660
1661     return nullptr;
1662   }
1663
1664   // Steal the created target, context, and preprocessor.
1665   AST->transferASTDataFromCompilerInstance(*Clang);
1666
1667   Act->EndSourceFile();
1668
1669   if (OwnAST)
1670     return OwnAST.release();
1671   else
1672     return AST;
1673 }
1674
1675 bool ASTUnit::LoadFromCompilerInvocation(
1676     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1677     unsigned PrecompilePreambleAfterNParses,
1678     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
1679   if (!Invocation)
1680     return true;
1681
1682   assert(VFS && "VFS is null");
1683
1684   // We'll manage file buffers ourselves.
1685   Invocation->getPreprocessorOpts().RetainRemappedFileBuffers = true;
1686   Invocation->getFrontendOpts().DisableFree = false;
1687   getDiagnostics().Reset();
1688   ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1689
1690   std::unique_ptr<llvm::MemoryBuffer> OverrideMainBuffer;
1691   if (PrecompilePreambleAfterNParses > 0) {
1692     PreambleRebuildCountdown = PrecompilePreambleAfterNParses;
1693     OverrideMainBuffer =
1694         getMainBufferWithPrecompiledPreamble(PCHContainerOps, *Invocation, VFS);
1695     getDiagnostics().Reset();
1696     ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1697   }
1698
1699   SimpleTimer ParsingTimer(WantTiming);
1700   ParsingTimer.setOutput("Parsing " + getMainFileName());
1701
1702   // Recover resources if we crash before exiting this method.
1703   llvm::CrashRecoveryContextCleanupRegistrar<llvm::MemoryBuffer>
1704     MemBufferCleanup(OverrideMainBuffer.get());
1705
1706   return Parse(std::move(PCHContainerOps), std::move(OverrideMainBuffer), VFS);
1707 }
1708
1709 std::unique_ptr<ASTUnit> ASTUnit::LoadFromCompilerInvocation(
1710     std::shared_ptr<CompilerInvocation> CI,
1711     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1712     IntrusiveRefCntPtr<DiagnosticsEngine> Diags, FileManager *FileMgr,
1713     bool OnlyLocalDecls, CaptureDiagsKind CaptureDiagnostics,
1714     unsigned PrecompilePreambleAfterNParses, TranslationUnitKind TUKind,
1715     bool CacheCodeCompletionResults, bool IncludeBriefCommentsInCodeCompletion,
1716     bool UserFilesAreVolatile) {
1717   // Create the AST unit.
1718   std::unique_ptr<ASTUnit> AST(new ASTUnit(false));
1719   ConfigureDiags(Diags, *AST, CaptureDiagnostics);
1720   AST->Diagnostics = Diags;
1721   AST->OnlyLocalDecls = OnlyLocalDecls;
1722   AST->CaptureDiagnostics = CaptureDiagnostics;
1723   AST->TUKind = TUKind;
1724   AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1725   AST->IncludeBriefCommentsInCodeCompletion
1726     = IncludeBriefCommentsInCodeCompletion;
1727   AST->Invocation = std::move(CI);
1728   AST->FileSystemOpts = FileMgr->getFileSystemOpts();
1729   AST->FileMgr = FileMgr;
1730   AST->UserFilesAreVolatile = UserFilesAreVolatile;
1731
1732   // Recover resources if we crash before exiting this method.
1733   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
1734     ASTUnitCleanup(AST.get());
1735   llvm::CrashRecoveryContextCleanupRegistrar<DiagnosticsEngine,
1736     llvm::CrashRecoveryContextReleaseRefCleanup<DiagnosticsEngine>>
1737     DiagCleanup(Diags.get());
1738
1739   if (AST->LoadFromCompilerInvocation(std::move(PCHContainerOps),
1740                                       PrecompilePreambleAfterNParses,
1741                                       &AST->FileMgr->getVirtualFileSystem()))
1742     return nullptr;
1743   return AST;
1744 }
1745
1746 std::unique_ptr<ASTUnit> ASTUnit::LoadFromCommandLine(
1747     const char **ArgBegin, const char **ArgEnd,
1748     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1749     IntrusiveRefCntPtr<DiagnosticsEngine> Diags, StringRef ResourceFilesPath,
1750     bool StorePreamblesInMemory, StringRef PreambleStoragePath,
1751     bool OnlyLocalDecls, CaptureDiagsKind CaptureDiagnostics,
1752     ArrayRef<RemappedFile> RemappedFiles, bool RemappedFilesKeepOriginalName,
1753     unsigned PrecompilePreambleAfterNParses, TranslationUnitKind TUKind,
1754     bool CacheCodeCompletionResults, bool IncludeBriefCommentsInCodeCompletion,
1755     bool AllowPCHWithCompilerErrors, SkipFunctionBodiesScope SkipFunctionBodies,
1756     bool SingleFileParse, bool UserFilesAreVolatile, bool ForSerialization,
1757     bool RetainExcludedConditionalBlocks, std::optional<StringRef> ModuleFormat,
1758     std::unique_ptr<ASTUnit> *ErrAST,
1759     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
1760   assert(Diags.get() && "no DiagnosticsEngine was provided");
1761
1762   // If no VFS was provided, create one that tracks the physical file system.
1763   // If '-working-directory' was passed as an argument, 'createInvocation' will
1764   // set this as the current working directory of the VFS.
1765   if (!VFS)
1766     VFS = llvm::vfs::createPhysicalFileSystem();
1767
1768   SmallVector<StoredDiagnostic, 4> StoredDiagnostics;
1769
1770   std::shared_ptr<CompilerInvocation> CI;
1771
1772   {
1773     CaptureDroppedDiagnostics Capture(CaptureDiagnostics, *Diags,
1774                                       &StoredDiagnostics, nullptr);
1775
1776     CreateInvocationOptions CIOpts;
1777     CIOpts.VFS = VFS;
1778     CIOpts.Diags = Diags;
1779     CIOpts.ProbePrecompiled = true; // FIXME: historical default. Needed?
1780     CI = createInvocation(llvm::ArrayRef(ArgBegin, ArgEnd), std::move(CIOpts));
1781     if (!CI)
1782       return nullptr;
1783   }
1784
1785   // Override any files that need remapping
1786   for (const auto &RemappedFile : RemappedFiles) {
1787     CI->getPreprocessorOpts().addRemappedFile(RemappedFile.first,
1788                                               RemappedFile.second);
1789   }
1790   PreprocessorOptions &PPOpts = CI->getPreprocessorOpts();
1791   PPOpts.RemappedFilesKeepOriginalName = RemappedFilesKeepOriginalName;
1792   PPOpts.AllowPCHWithCompilerErrors = AllowPCHWithCompilerErrors;
1793   PPOpts.SingleFileParseMode = SingleFileParse;
1794   PPOpts.RetainExcludedConditionalBlocks = RetainExcludedConditionalBlocks;
1795
1796   // Override the resources path.
1797   CI->getHeaderSearchOpts().ResourceDir = std::string(ResourceFilesPath);
1798
1799   CI->getFrontendOpts().SkipFunctionBodies =
1800       SkipFunctionBodies == SkipFunctionBodiesScope::PreambleAndMainFile;
1801
1802   if (ModuleFormat)
1803     CI->getHeaderSearchOpts().ModuleFormat = std::string(*ModuleFormat);
1804
1805   // Create the AST unit.
1806   std::unique_ptr<ASTUnit> AST;
1807   AST.reset(new ASTUnit(false));
1808   AST->NumStoredDiagnosticsFromDriver = StoredDiagnostics.size();
1809   AST->StoredDiagnostics.swap(StoredDiagnostics);
1810   ConfigureDiags(Diags, *AST, CaptureDiagnostics);
1811   AST->Diagnostics = Diags;
1812   AST->FileSystemOpts = CI->getFileSystemOpts();
1813   VFS = createVFSFromCompilerInvocation(*CI, *Diags, VFS);
1814   AST->FileMgr = new FileManager(AST->FileSystemOpts, VFS);
1815   AST->StorePreamblesInMemory = StorePreamblesInMemory;
1816   AST->PreambleStoragePath = PreambleStoragePath;
1817   AST->ModuleCache = new InMemoryModuleCache;
1818   AST->OnlyLocalDecls = OnlyLocalDecls;
1819   AST->CaptureDiagnostics = CaptureDiagnostics;
1820   AST->TUKind = TUKind;
1821   AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1822   AST->IncludeBriefCommentsInCodeCompletion
1823     = IncludeBriefCommentsInCodeCompletion;
1824   AST->UserFilesAreVolatile = UserFilesAreVolatile;
1825   AST->Invocation = CI;
1826   AST->SkipFunctionBodies = SkipFunctionBodies;
1827   if (ForSerialization)
1828     AST->WriterData.reset(new ASTWriterData(*AST->ModuleCache));
1829   // Zero out now to ease cleanup during crash recovery.
1830   CI = nullptr;
1831   Diags = nullptr;
1832
1833   // Recover resources if we crash before exiting this method.
1834   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
1835     ASTUnitCleanup(AST.get());
1836
1837   if (AST->LoadFromCompilerInvocation(std::move(PCHContainerOps),
1838                                       PrecompilePreambleAfterNParses,
1839                                       VFS)) {
1840     // Some error occurred, if caller wants to examine diagnostics, pass it the
1841     // ASTUnit.
1842     if (ErrAST) {
1843       AST->StoredDiagnostics.swap(AST->FailedParseDiagnostics);
1844       ErrAST->swap(AST);
1845     }
1846     return nullptr;
1847   }
1848
1849   return AST;
1850 }
1851
1852 bool ASTUnit::Reparse(std::shared_ptr<PCHContainerOperations> PCHContainerOps,
1853                       ArrayRef<RemappedFile> RemappedFiles,
1854                       IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
1855   if (!Invocation)
1856     return true;
1857
1858   if (!VFS) {
1859     assert(FileMgr && "FileMgr is null on Reparse call");
1860     VFS = &FileMgr->getVirtualFileSystem();
1861   }
1862
1863   clearFileLevelDecls();
1864
1865   SimpleTimer ParsingTimer(WantTiming);
1866   ParsingTimer.setOutput("Reparsing " + getMainFileName());
1867
1868   // Remap files.
1869   PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
1870   for (const auto &RB : PPOpts.RemappedFileBuffers)
1871     delete RB.second;
1872
1873   Invocation->getPreprocessorOpts().clearRemappedFiles();
1874   for (const auto &RemappedFile : RemappedFiles) {
1875     Invocation->getPreprocessorOpts().addRemappedFile(RemappedFile.first,
1876                                                       RemappedFile.second);
1877   }
1878
1879   // If we have a preamble file lying around, or if we might try to
1880   // build a precompiled preamble, do so now.
1881   std::unique_ptr<llvm::MemoryBuffer> OverrideMainBuffer;
1882   if (Preamble || PreambleRebuildCountdown > 0)
1883     OverrideMainBuffer =
1884         getMainBufferWithPrecompiledPreamble(PCHContainerOps, *Invocation, VFS);
1885
1886   // Clear out the diagnostics state.
1887   FileMgr.reset();
1888   getDiagnostics().Reset();
1889   ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1890   if (OverrideMainBuffer)
1891     getDiagnostics().setNumWarnings(NumWarningsInPreamble);
1892
1893   // Parse the sources
1894   bool Result =
1895       Parse(std::move(PCHContainerOps), std::move(OverrideMainBuffer), VFS);
1896
1897   // If we're caching global code-completion results, and the top-level
1898   // declarations have changed, clear out the code-completion cache.
1899   if (!Result && ShouldCacheCodeCompletionResults &&
1900       CurrentTopLevelHashValue != CompletionCacheTopLevelHashValue)
1901     CacheCodeCompletionResults();
1902
1903   // We now need to clear out the completion info related to this translation
1904   // unit; it'll be recreated if necessary.
1905   CCTUInfo.reset();
1906
1907   return Result;
1908 }
1909
1910 void ASTUnit::ResetForParse() {
1911   SavedMainFileBuffer.reset();
1912
1913   SourceMgr.reset();
1914   TheSema.reset();
1915   Ctx.reset();
1916   PP.reset();
1917   Reader.reset();
1918
1919   TopLevelDecls.clear();
1920   clearFileLevelDecls();
1921 }
1922
1923 //----------------------------------------------------------------------------//
1924 // Code completion
1925 //----------------------------------------------------------------------------//
1926
1927 namespace {
1928
1929   /// Code completion consumer that combines the cached code-completion
1930   /// results from an ASTUnit with the code-completion results provided to it,
1931   /// then passes the result on to
1932   class AugmentedCodeCompleteConsumer : public CodeCompleteConsumer {
1933     uint64_t NormalContexts;
1934     ASTUnit &AST;
1935     CodeCompleteConsumer &Next;
1936
1937   public:
1938     AugmentedCodeCompleteConsumer(ASTUnit &AST, CodeCompleteConsumer &Next,
1939                                   const CodeCompleteOptions &CodeCompleteOpts)
1940         : CodeCompleteConsumer(CodeCompleteOpts), AST(AST), Next(Next) {
1941       // Compute the set of contexts in which we will look when we don't have
1942       // any information about the specific context.
1943       NormalContexts
1944         = (1LL << CodeCompletionContext::CCC_TopLevel)
1945         | (1LL << CodeCompletionContext::CCC_ObjCInterface)
1946         | (1LL << CodeCompletionContext::CCC_ObjCImplementation)
1947         | (1LL << CodeCompletionContext::CCC_ObjCIvarList)
1948         | (1LL << CodeCompletionContext::CCC_Statement)
1949         | (1LL << CodeCompletionContext::CCC_Expression)
1950         | (1LL << CodeCompletionContext::CCC_ObjCMessageReceiver)
1951         | (1LL << CodeCompletionContext::CCC_DotMemberAccess)
1952         | (1LL << CodeCompletionContext::CCC_ArrowMemberAccess)
1953         | (1LL << CodeCompletionContext::CCC_ObjCPropertyAccess)
1954         | (1LL << CodeCompletionContext::CCC_ObjCProtocolName)
1955         | (1LL << CodeCompletionContext::CCC_ParenthesizedExpression)
1956         | (1LL << CodeCompletionContext::CCC_Recovery);
1957
1958       if (AST.getASTContext().getLangOpts().CPlusPlus)
1959         NormalContexts |= (1LL << CodeCompletionContext::CCC_EnumTag)
1960                        |  (1LL << CodeCompletionContext::CCC_UnionTag)
1961                        |  (1LL << CodeCompletionContext::CCC_ClassOrStructTag);
1962     }
1963
1964     void ProcessCodeCompleteResults(Sema &S, CodeCompletionContext Context,
1965                                     CodeCompletionResult *Results,
1966                                     unsigned NumResults) override;
1967
1968     void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
1969                                    OverloadCandidate *Candidates,
1970                                    unsigned NumCandidates,
1971                                    SourceLocation OpenParLoc,
1972                                    bool Braced) override {
1973       Next.ProcessOverloadCandidates(S, CurrentArg, Candidates, NumCandidates,
1974                                      OpenParLoc, Braced);
1975     }
1976
1977     CodeCompletionAllocator &getAllocator() override {
1978       return Next.getAllocator();
1979     }
1980
1981     CodeCompletionTUInfo &getCodeCompletionTUInfo() override {
1982       return Next.getCodeCompletionTUInfo();
1983     }
1984   };
1985
1986 } // namespace
1987
1988 /// Helper function that computes which global names are hidden by the
1989 /// local code-completion results.
1990 static void CalculateHiddenNames(const CodeCompletionContext &Context,
1991                                  CodeCompletionResult *Results,
1992                                  unsigned NumResults,
1993                                  ASTContext &Ctx,
1994                           llvm::StringSet<llvm::BumpPtrAllocator> &HiddenNames){
1995   bool OnlyTagNames = false;
1996   switch (Context.getKind()) {
1997   case CodeCompletionContext::CCC_Recovery:
1998   case CodeCompletionContext::CCC_TopLevel:
1999   case CodeCompletionContext::CCC_ObjCInterface:
2000   case CodeCompletionContext::CCC_ObjCImplementation:
2001   case CodeCompletionContext::CCC_ObjCIvarList:
2002   case CodeCompletionContext::CCC_ClassStructUnion:
2003   case CodeCompletionContext::CCC_Statement:
2004   case CodeCompletionContext::CCC_Expression:
2005   case CodeCompletionContext::CCC_ObjCMessageReceiver:
2006   case CodeCompletionContext::CCC_DotMemberAccess:
2007   case CodeCompletionContext::CCC_ArrowMemberAccess:
2008   case CodeCompletionContext::CCC_ObjCPropertyAccess:
2009   case CodeCompletionContext::CCC_Namespace:
2010   case CodeCompletionContext::CCC_Type:
2011   case CodeCompletionContext::CCC_Symbol:
2012   case CodeCompletionContext::CCC_SymbolOrNewName:
2013   case CodeCompletionContext::CCC_ParenthesizedExpression:
2014   case CodeCompletionContext::CCC_ObjCInterfaceName:
2015   case CodeCompletionContext::CCC_TopLevelOrExpression:
2016       break;
2017
2018   case CodeCompletionContext::CCC_EnumTag:
2019   case CodeCompletionContext::CCC_UnionTag:
2020   case CodeCompletionContext::CCC_ClassOrStructTag:
2021     OnlyTagNames = true;
2022     break;
2023
2024   case CodeCompletionContext::CCC_ObjCProtocolName:
2025   case CodeCompletionContext::CCC_MacroName:
2026   case CodeCompletionContext::CCC_MacroNameUse:
2027   case CodeCompletionContext::CCC_PreprocessorExpression:
2028   case CodeCompletionContext::CCC_PreprocessorDirective:
2029   case CodeCompletionContext::CCC_NaturalLanguage:
2030   case CodeCompletionContext::CCC_SelectorName:
2031   case CodeCompletionContext::CCC_TypeQualifiers:
2032   case CodeCompletionContext::CCC_Other:
2033   case CodeCompletionContext::CCC_OtherWithMacros:
2034   case CodeCompletionContext::CCC_ObjCInstanceMessage:
2035   case CodeCompletionContext::CCC_ObjCClassMessage:
2036   case CodeCompletionContext::CCC_ObjCCategoryName:
2037   case CodeCompletionContext::CCC_IncludedFile:
2038   case CodeCompletionContext::CCC_Attribute:
2039   case CodeCompletionContext::CCC_NewName:
2040   case CodeCompletionContext::CCC_ObjCClassForwardDecl:
2041     // We're looking for nothing, or we're looking for names that cannot
2042     // be hidden.
2043     return;
2044   }
2045
2046   using Result = CodeCompletionResult;
2047   for (unsigned I = 0; I != NumResults; ++I) {
2048     if (Results[I].Kind != Result::RK_Declaration)
2049       continue;
2050
2051     unsigned IDNS
2052       = Results[I].Declaration->getUnderlyingDecl()->getIdentifierNamespace();
2053
2054     bool Hiding = false;
2055     if (OnlyTagNames)
2056       Hiding = (IDNS & Decl::IDNS_Tag);
2057     else {
2058       unsigned HiddenIDNS = (Decl::IDNS_Type | Decl::IDNS_Member |
2059                              Decl::IDNS_Namespace | Decl::IDNS_Ordinary |
2060                              Decl::IDNS_NonMemberOperator);
2061       if (Ctx.getLangOpts().CPlusPlus)
2062         HiddenIDNS |= Decl::IDNS_Tag;
2063       Hiding = (IDNS & HiddenIDNS);
2064     }
2065
2066     if (!Hiding)
2067       continue;
2068
2069     DeclarationName Name = Results[I].Declaration->getDeclName();
2070     if (IdentifierInfo *Identifier = Name.getAsIdentifierInfo())
2071       HiddenNames.insert(Identifier->getName());
2072     else
2073       HiddenNames.insert(Name.getAsString());
2074   }
2075 }
2076
2077 void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
2078                                             CodeCompletionContext Context,
2079                                             CodeCompletionResult *Results,
2080                                             unsigned NumResults) {
2081   // Merge the results we were given with the results we cached.
2082   bool AddedResult = false;
2083   uint64_t InContexts =
2084       Context.getKind() == CodeCompletionContext::CCC_Recovery
2085         ? NormalContexts : (1LL << Context.getKind());
2086   // Contains the set of names that are hidden by "local" completion results.
2087   llvm::StringSet<llvm::BumpPtrAllocator> HiddenNames;
2088   using Result = CodeCompletionResult;
2089   SmallVector<Result, 8> AllResults;
2090   for (ASTUnit::cached_completion_iterator
2091             C = AST.cached_completion_begin(),
2092          CEnd = AST.cached_completion_end();
2093        C != CEnd; ++C) {
2094     // If the context we are in matches any of the contexts we are
2095     // interested in, we'll add this result.
2096     if ((C->ShowInContexts & InContexts) == 0)
2097       continue;
2098
2099     // If we haven't added any results previously, do so now.
2100     if (!AddedResult) {
2101       CalculateHiddenNames(Context, Results, NumResults, S.Context,
2102                            HiddenNames);
2103       AllResults.insert(AllResults.end(), Results, Results + NumResults);
2104       AddedResult = true;
2105     }
2106
2107     // Determine whether this global completion result is hidden by a local
2108     // completion result. If so, skip it.
2109     if (C->Kind != CXCursor_MacroDefinition &&
2110         HiddenNames.count(C->Completion->getTypedText()))
2111       continue;
2112
2113     // Adjust priority based on similar type classes.
2114     unsigned Priority = C->Priority;
2115     CodeCompletionString *Completion = C->Completion;
2116     if (!Context.getPreferredType().isNull()) {
2117       if (C->Kind == CXCursor_MacroDefinition) {
2118         Priority = getMacroUsagePriority(C->Completion->getTypedText(),
2119                                          S.getLangOpts(),
2120                                Context.getPreferredType()->isAnyPointerType());
2121       } else if (C->Type) {
2122         CanQualType Expected
2123           = S.Context.getCanonicalType(
2124                                Context.getPreferredType().getUnqualifiedType());
2125         SimplifiedTypeClass ExpectedSTC = getSimplifiedTypeClass(Expected);
2126         if (ExpectedSTC == C->TypeClass) {
2127           // We know this type is similar; check for an exact match.
2128           llvm::StringMap<unsigned> &CachedCompletionTypes
2129             = AST.getCachedCompletionTypes();
2130           llvm::StringMap<unsigned>::iterator Pos
2131             = CachedCompletionTypes.find(QualType(Expected).getAsString());
2132           if (Pos != CachedCompletionTypes.end() && Pos->second == C->Type)
2133             Priority /= CCF_ExactTypeMatch;
2134           else
2135             Priority /= CCF_SimilarTypeMatch;
2136         }
2137       }
2138     }
2139
2140     // Adjust the completion string, if required.
2141     if (C->Kind == CXCursor_MacroDefinition &&
2142         Context.getKind() == CodeCompletionContext::CCC_MacroNameUse) {
2143       // Create a new code-completion string that just contains the
2144       // macro name, without its arguments.
2145       CodeCompletionBuilder Builder(getAllocator(), getCodeCompletionTUInfo(),
2146                                     CCP_CodePattern, C->Availability);
2147       Builder.AddTypedTextChunk(C->Completion->getTypedText());
2148       Priority = CCP_CodePattern;
2149       Completion = Builder.TakeString();
2150     }
2151
2152     AllResults.push_back(Result(Completion, Priority, C->Kind,
2153                                 C->Availability));
2154   }
2155
2156   // If we did not add any cached completion results, just forward the
2157   // results we were given to the next consumer.
2158   if (!AddedResult) {
2159     Next.ProcessCodeCompleteResults(S, Context, Results, NumResults);
2160     return;
2161   }
2162
2163   Next.ProcessCodeCompleteResults(S, Context, AllResults.data(),
2164                                   AllResults.size());
2165 }
2166
2167 void ASTUnit::CodeComplete(
2168     StringRef File, unsigned Line, unsigned Column,
2169     ArrayRef<RemappedFile> RemappedFiles, bool IncludeMacros,
2170     bool IncludeCodePatterns, bool IncludeBriefComments,
2171     CodeCompleteConsumer &Consumer,
2172     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
2173     DiagnosticsEngine &Diag, LangOptions &LangOpts, SourceManager &SourceMgr,
2174     FileManager &FileMgr, SmallVectorImpl<StoredDiagnostic> &StoredDiagnostics,
2175     SmallVectorImpl<const llvm::MemoryBuffer *> &OwnedBuffers,
2176     std::unique_ptr<SyntaxOnlyAction> Act) {
2177   if (!Invocation)
2178     return;
2179
2180   SimpleTimer CompletionTimer(WantTiming);
2181   CompletionTimer.setOutput("Code completion @ " + File + ":" +
2182                             Twine(Line) + ":" + Twine(Column));
2183
2184   auto CCInvocation = std::make_shared<CompilerInvocation>(*Invocation);
2185
2186   FrontendOptions &FrontendOpts = CCInvocation->getFrontendOpts();
2187   CodeCompleteOptions &CodeCompleteOpts = FrontendOpts.CodeCompleteOpts;
2188   PreprocessorOptions &PreprocessorOpts = CCInvocation->getPreprocessorOpts();
2189
2190   CodeCompleteOpts.IncludeMacros = IncludeMacros &&
2191                                    CachedCompletionResults.empty();
2192   CodeCompleteOpts.IncludeCodePatterns = IncludeCodePatterns;
2193   CodeCompleteOpts.IncludeGlobals = CachedCompletionResults.empty();
2194   CodeCompleteOpts.IncludeBriefComments = IncludeBriefComments;
2195   CodeCompleteOpts.LoadExternal = Consumer.loadExternal();
2196   CodeCompleteOpts.IncludeFixIts = Consumer.includeFixIts();
2197
2198   assert(IncludeBriefComments == this->IncludeBriefCommentsInCodeCompletion);
2199
2200   FrontendOpts.CodeCompletionAt.FileName = std::string(File);
2201   FrontendOpts.CodeCompletionAt.Line = Line;
2202   FrontendOpts.CodeCompletionAt.Column = Column;
2203
2204   // Set the language options appropriately.
2205   LangOpts = CCInvocation->getLangOpts();
2206
2207   // Spell-checking and warnings are wasteful during code-completion.
2208   LangOpts.SpellChecking = false;
2209   CCInvocation->getDiagnosticOpts().IgnoreWarnings = true;
2210
2211   std::unique_ptr<CompilerInstance> Clang(
2212       new CompilerInstance(PCHContainerOps));
2213
2214   // Recover resources if we crash before exiting this method.
2215   llvm::CrashRecoveryContextCleanupRegistrar<CompilerInstance>
2216     CICleanup(Clang.get());
2217
2218   auto &Inv = *CCInvocation;
2219   Clang->setInvocation(std::move(CCInvocation));
2220   OriginalSourceFile =
2221       std::string(Clang->getFrontendOpts().Inputs[0].getFile());
2222
2223   // Set up diagnostics, capturing any diagnostics produced.
2224   Clang->setDiagnostics(&Diag);
2225   CaptureDroppedDiagnostics Capture(CaptureDiagsKind::All,
2226                                     Clang->getDiagnostics(),
2227                                     &StoredDiagnostics, nullptr);
2228   ProcessWarningOptions(Diag, Inv.getDiagnosticOpts());
2229
2230   // Create the target instance.
2231   if (!Clang->createTarget()) {
2232     Clang->setInvocation(nullptr);
2233     return;
2234   }
2235
2236   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
2237          "Invocation must have exactly one source file!");
2238   assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
2239              InputKind::Source &&
2240          "FIXME: AST inputs not yet supported here!");
2241   assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
2242              Language::LLVM_IR &&
2243          "IR inputs not support here!");
2244
2245   // Use the source and file managers that we were given.
2246   Clang->setFileManager(&FileMgr);
2247   Clang->setSourceManager(&SourceMgr);
2248
2249   // Remap files.
2250   PreprocessorOpts.clearRemappedFiles();
2251   PreprocessorOpts.RetainRemappedFileBuffers = true;
2252   for (const auto &RemappedFile : RemappedFiles) {
2253     PreprocessorOpts.addRemappedFile(RemappedFile.first, RemappedFile.second);
2254     OwnedBuffers.push_back(RemappedFile.second);
2255   }
2256
2257   // Use the code completion consumer we were given, but adding any cached
2258   // code-completion results.
2259   AugmentedCodeCompleteConsumer *AugmentedConsumer
2260     = new AugmentedCodeCompleteConsumer(*this, Consumer, CodeCompleteOpts);
2261   Clang->setCodeCompletionConsumer(AugmentedConsumer);
2262
2263   auto getUniqueID =
2264       [&FileMgr](StringRef Filename) -> std::optional<llvm::sys::fs::UniqueID> {
2265     if (auto Status = FileMgr.getVirtualFileSystem().status(Filename))
2266       return Status->getUniqueID();
2267     return std::nullopt;
2268   };
2269
2270   auto hasSameUniqueID = [getUniqueID](StringRef LHS, StringRef RHS) {
2271     if (LHS == RHS)
2272       return true;
2273     if (auto LHSID = getUniqueID(LHS))
2274       if (auto RHSID = getUniqueID(RHS))
2275         return *LHSID == *RHSID;
2276     return false;
2277   };
2278
2279   // If we have a precompiled preamble, try to use it. We only allow
2280   // the use of the precompiled preamble if we're if the completion
2281   // point is within the main file, after the end of the precompiled
2282   // preamble.
2283   std::unique_ptr<llvm::MemoryBuffer> OverrideMainBuffer;
2284   if (Preamble && Line > 1 && hasSameUniqueID(File, OriginalSourceFile)) {
2285     OverrideMainBuffer = getMainBufferWithPrecompiledPreamble(
2286         PCHContainerOps, Inv, &FileMgr.getVirtualFileSystem(), false, Line - 1);
2287   }
2288
2289   // If the main file has been overridden due to the use of a preamble,
2290   // make that override happen and introduce the preamble.
2291   if (OverrideMainBuffer) {
2292     assert(Preamble &&
2293            "No preamble was built, but OverrideMainBuffer is not null");
2294
2295     IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
2296         &FileMgr.getVirtualFileSystem();
2297     Preamble->AddImplicitPreamble(Clang->getInvocation(), VFS,
2298                                   OverrideMainBuffer.get());
2299     // FIXME: there is no way to update VFS if it was changed by
2300     // AddImplicitPreamble as FileMgr is accepted as a parameter by this method.
2301     // We use on-disk preambles instead and rely on FileMgr's VFS to ensure the
2302     // PCH files are always readable.
2303     OwnedBuffers.push_back(OverrideMainBuffer.release());
2304   } else {
2305     PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
2306     PreprocessorOpts.PrecompiledPreambleBytes.second = false;
2307   }
2308
2309   // Disable the preprocessing record if modules are not enabled.
2310   if (!Clang->getLangOpts().Modules)
2311     PreprocessorOpts.DetailedRecord = false;
2312
2313   if (!Act)
2314     Act.reset(new SyntaxOnlyAction);
2315
2316   if (Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0])) {
2317     if (llvm::Error Err = Act->Execute()) {
2318       consumeError(std::move(Err)); // FIXME this drops errors on the floor.
2319     }
2320     Act->EndSourceFile();
2321   }
2322 }
2323
2324 bool ASTUnit::Save(StringRef File) {
2325   if (HadModuleLoaderFatalFailure)
2326     return true;
2327
2328   // FIXME: Can we somehow regenerate the stat cache here, or do we need to
2329   // unconditionally create a stat cache when we parse the file?
2330
2331   if (llvm::Error Err = llvm::writeToOutput(
2332           File, [this](llvm::raw_ostream &Out) {
2333             return serialize(Out) ? llvm::make_error<llvm::StringError>(
2334                                         "ASTUnit serialization failed",
2335                                         llvm::inconvertibleErrorCode())
2336                                   : llvm::Error::success();
2337           })) {
2338     consumeError(std::move(Err));
2339     return true;
2340   }
2341   return false;
2342 }
2343
2344 static bool serializeUnit(ASTWriter &Writer, SmallVectorImpl<char> &Buffer,
2345                           Sema &S, raw_ostream &OS) {
2346   Writer.WriteAST(S, std::string(), nullptr, "");
2347
2348   // Write the generated bitstream to "Out".
2349   if (!Buffer.empty())
2350     OS.write(Buffer.data(), Buffer.size());
2351
2352   return false;
2353 }
2354
2355 bool ASTUnit::serialize(raw_ostream &OS) {
2356   if (WriterData)
2357     return serializeUnit(WriterData->Writer, WriterData->Buffer, getSema(), OS);
2358
2359   SmallString<128> Buffer;
2360   llvm::BitstreamWriter Stream(Buffer);
2361   InMemoryModuleCache ModuleCache;
2362   ASTWriter Writer(Stream, Buffer, ModuleCache, {});
2363   return serializeUnit(Writer, Buffer, getSema(), OS);
2364 }
2365
2366 using SLocRemap = ContinuousRangeMap<unsigned, int, 2>;
2367
2368 void ASTUnit::TranslateStoredDiagnostics(
2369                           FileManager &FileMgr,
2370                           SourceManager &SrcMgr,
2371                           const SmallVectorImpl<StandaloneDiagnostic> &Diags,
2372                           SmallVectorImpl<StoredDiagnostic> &Out) {
2373   // Map the standalone diagnostic into the new source manager. We also need to
2374   // remap all the locations to the new view. This includes the diag location,
2375   // any associated source ranges, and the source ranges of associated fix-its.
2376   // FIXME: There should be a cleaner way to do this.
2377   SmallVector<StoredDiagnostic, 4> Result;
2378   Result.reserve(Diags.size());
2379
2380   for (const auto &SD : Diags) {
2381     // Rebuild the StoredDiagnostic.
2382     if (SD.Filename.empty())
2383       continue;
2384     auto FE = FileMgr.getFile(SD.Filename);
2385     if (!FE)
2386       continue;
2387     SourceLocation FileLoc;
2388     auto ItFileID = PreambleSrcLocCache.find(SD.Filename);
2389     if (ItFileID == PreambleSrcLocCache.end()) {
2390       FileID FID = SrcMgr.translateFile(*FE);
2391       FileLoc = SrcMgr.getLocForStartOfFile(FID);
2392       PreambleSrcLocCache[SD.Filename] = FileLoc;
2393     } else {
2394       FileLoc = ItFileID->getValue();
2395     }
2396
2397     if (FileLoc.isInvalid())
2398       continue;
2399     SourceLocation L = FileLoc.getLocWithOffset(SD.LocOffset);
2400     FullSourceLoc Loc(L, SrcMgr);
2401
2402     SmallVector<CharSourceRange, 4> Ranges;
2403     Ranges.reserve(SD.Ranges.size());
2404     for (const auto &Range : SD.Ranges) {
2405       SourceLocation BL = FileLoc.getLocWithOffset(Range.first);
2406       SourceLocation EL = FileLoc.getLocWithOffset(Range.second);
2407       Ranges.push_back(CharSourceRange::getCharRange(BL, EL));
2408     }
2409
2410     SmallVector<FixItHint, 2> FixIts;
2411     FixIts.reserve(SD.FixIts.size());
2412     for (const auto &FixIt : SD.FixIts) {
2413       FixIts.push_back(FixItHint());
2414       FixItHint &FH = FixIts.back();
2415       FH.CodeToInsert = FixIt.CodeToInsert;
2416       SourceLocation BL = FileLoc.getLocWithOffset(FixIt.RemoveRange.first);
2417       SourceLocation EL = FileLoc.getLocWithOffset(FixIt.RemoveRange.second);
2418       FH.RemoveRange = CharSourceRange::getCharRange(BL, EL);
2419     }
2420
2421     Result.push_back(StoredDiagnostic(SD.Level, SD.ID,
2422                                       SD.Message, Loc, Ranges, FixIts));
2423   }
2424   Result.swap(Out);
2425 }
2426
2427 void ASTUnit::addFileLevelDecl(Decl *D) {
2428   assert(D);
2429
2430   // We only care about local declarations.
2431   if (D->isFromASTFile())
2432     return;
2433
2434   SourceManager &SM = *SourceMgr;
2435   SourceLocation Loc = D->getLocation();
2436   if (Loc.isInvalid() || !SM.isLocalSourceLocation(Loc))
2437     return;
2438
2439   // We only keep track of the file-level declarations of each file.
2440   if (!D->getLexicalDeclContext()->isFileContext())
2441     return;
2442
2443   SourceLocation FileLoc = SM.getFileLoc(Loc);
2444   assert(SM.isLocalSourceLocation(FileLoc));
2445   FileID FID;
2446   unsigned Offset;
2447   std::tie(FID, Offset) = SM.getDecomposedLoc(FileLoc);
2448   if (FID.isInvalid())
2449     return;
2450
2451   std::unique_ptr<LocDeclsTy> &Decls = FileDecls[FID];
2452   if (!Decls)
2453     Decls = std::make_unique<LocDeclsTy>();
2454
2455   std::pair<unsigned, Decl *> LocDecl(Offset, D);
2456
2457   if (Decls->empty() || Decls->back().first <= Offset) {
2458     Decls->push_back(LocDecl);
2459     return;
2460   }
2461
2462   LocDeclsTy::iterator I =
2463       llvm::upper_bound(*Decls, LocDecl, llvm::less_first());
2464
2465   Decls->insert(I, LocDecl);
2466 }
2467
2468 void ASTUnit::findFileRegionDecls(FileID File, unsigned Offset, unsigned Length,
2469                                   SmallVectorImpl<Decl *> &Decls) {
2470   if (File.isInvalid())
2471     return;
2472
2473   if (SourceMgr->isLoadedFileID(File)) {
2474     assert(Ctx->getExternalSource() && "No external source!");
2475     return Ctx->getExternalSource()->FindFileRegionDecls(File, Offset, Length,
2476                                                          Decls);
2477   }
2478
2479   FileDeclsTy::iterator I = FileDecls.find(File);
2480   if (I == FileDecls.end())
2481     return;
2482
2483   LocDeclsTy &LocDecls = *I->second;
2484   if (LocDecls.empty())
2485     return;
2486
2487   LocDeclsTy::iterator BeginIt =
2488       llvm::partition_point(LocDecls, [=](std::pair<unsigned, Decl *> LD) {
2489         return LD.first < Offset;
2490       });
2491   if (BeginIt != LocDecls.begin())
2492     --BeginIt;
2493
2494   // If we are pointing at a top-level decl inside an objc container, we need
2495   // to backtrack until we find it otherwise we will fail to report that the
2496   // region overlaps with an objc container.
2497   while (BeginIt != LocDecls.begin() &&
2498          BeginIt->second->isTopLevelDeclInObjCContainer())
2499     --BeginIt;
2500
2501   LocDeclsTy::iterator EndIt = llvm::upper_bound(
2502       LocDecls, std::make_pair(Offset + Length, (Decl *)nullptr),
2503       llvm::less_first());
2504   if (EndIt != LocDecls.end())
2505     ++EndIt;
2506
2507   for (LocDeclsTy::iterator DIt = BeginIt; DIt != EndIt; ++DIt)
2508     Decls.push_back(DIt->second);
2509 }
2510
2511 SourceLocation ASTUnit::getLocation(const FileEntry *File,
2512                                     unsigned Line, unsigned Col) const {
2513   const SourceManager &SM = getSourceManager();
2514   SourceLocation Loc = SM.translateFileLineCol(File, Line, Col);
2515   return SM.getMacroArgExpandedLocation(Loc);
2516 }
2517
2518 SourceLocation ASTUnit::getLocation(const FileEntry *File,
2519                                     unsigned Offset) const {
2520   const SourceManager &SM = getSourceManager();
2521   SourceLocation FileLoc = SM.translateFileLineCol(File, 1, 1);
2522   return SM.getMacroArgExpandedLocation(FileLoc.getLocWithOffset(Offset));
2523 }
2524
2525 /// If \arg Loc is a loaded location from the preamble, returns
2526 /// the corresponding local location of the main file, otherwise it returns
2527 /// \arg Loc.
2528 SourceLocation ASTUnit::mapLocationFromPreamble(SourceLocation Loc) const {
2529   FileID PreambleID;
2530   if (SourceMgr)
2531     PreambleID = SourceMgr->getPreambleFileID();
2532
2533   if (Loc.isInvalid() || !Preamble || PreambleID.isInvalid())
2534     return Loc;
2535
2536   unsigned Offs;
2537   if (SourceMgr->isInFileID(Loc, PreambleID, &Offs) && Offs < Preamble->getBounds().Size) {
2538     SourceLocation FileLoc
2539         = SourceMgr->getLocForStartOfFile(SourceMgr->getMainFileID());
2540     return FileLoc.getLocWithOffset(Offs);
2541   }
2542
2543   return Loc;
2544 }
2545
2546 /// If \arg Loc is a local location of the main file but inside the
2547 /// preamble chunk, returns the corresponding loaded location from the
2548 /// preamble, otherwise it returns \arg Loc.
2549 SourceLocation ASTUnit::mapLocationToPreamble(SourceLocation Loc) const {
2550   FileID PreambleID;
2551   if (SourceMgr)
2552     PreambleID = SourceMgr->getPreambleFileID();
2553
2554   if (Loc.isInvalid() || !Preamble || PreambleID.isInvalid())
2555     return Loc;
2556
2557   unsigned Offs;
2558   if (SourceMgr->isInFileID(Loc, SourceMgr->getMainFileID(), &Offs) &&
2559       Offs < Preamble->getBounds().Size) {
2560     SourceLocation FileLoc = SourceMgr->getLocForStartOfFile(PreambleID);
2561     return FileLoc.getLocWithOffset(Offs);
2562   }
2563
2564   return Loc;
2565 }
2566
2567 bool ASTUnit::isInPreambleFileID(SourceLocation Loc) const {
2568   FileID FID;
2569   if (SourceMgr)
2570     FID = SourceMgr->getPreambleFileID();
2571
2572   if (Loc.isInvalid() || FID.isInvalid())
2573     return false;
2574
2575   return SourceMgr->isInFileID(Loc, FID);
2576 }
2577
2578 bool ASTUnit::isInMainFileID(SourceLocation Loc) const {
2579   FileID FID;
2580   if (SourceMgr)
2581     FID = SourceMgr->getMainFileID();
2582
2583   if (Loc.isInvalid() || FID.isInvalid())
2584     return false;
2585
2586   return SourceMgr->isInFileID(Loc, FID);
2587 }
2588
2589 SourceLocation ASTUnit::getEndOfPreambleFileID() const {
2590   FileID FID;
2591   if (SourceMgr)
2592     FID = SourceMgr->getPreambleFileID();
2593
2594   if (FID.isInvalid())
2595     return {};
2596
2597   return SourceMgr->getLocForEndOfFile(FID);
2598 }
2599
2600 SourceLocation ASTUnit::getStartOfMainFileID() const {
2601   FileID FID;
2602   if (SourceMgr)
2603     FID = SourceMgr->getMainFileID();
2604
2605   if (FID.isInvalid())
2606     return {};
2607
2608   return SourceMgr->getLocForStartOfFile(FID);
2609 }
2610
2611 llvm::iterator_range<PreprocessingRecord::iterator>
2612 ASTUnit::getLocalPreprocessingEntities() const {
2613   if (isMainFileAST()) {
2614     serialization::ModuleFile &
2615       Mod = Reader->getModuleManager().getPrimaryModule();
2616     return Reader->getModulePreprocessedEntities(Mod);
2617   }
2618
2619   if (PreprocessingRecord *PPRec = PP->getPreprocessingRecord())
2620     return llvm::make_range(PPRec->local_begin(), PPRec->local_end());
2621
2622   return llvm::make_range(PreprocessingRecord::iterator(),
2623                           PreprocessingRecord::iterator());
2624 }
2625
2626 bool ASTUnit::visitLocalTopLevelDecls(void *context, DeclVisitorFn Fn) {
2627   if (isMainFileAST()) {
2628     serialization::ModuleFile &
2629       Mod = Reader->getModuleManager().getPrimaryModule();
2630     for (const auto *D : Reader->getModuleFileLevelDecls(Mod)) {
2631       if (!Fn(context, D))
2632         return false;
2633     }
2634
2635     return true;
2636   }
2637
2638   for (ASTUnit::top_level_iterator TL = top_level_begin(),
2639                                 TLEnd = top_level_end();
2640          TL != TLEnd; ++TL) {
2641     if (!Fn(context, *TL))
2642       return false;
2643   }
2644
2645   return true;
2646 }
2647
2648 OptionalFileEntryRef ASTUnit::getPCHFile() {
2649   if (!Reader)
2650     return std::nullopt;
2651
2652   serialization::ModuleFile *Mod = nullptr;
2653   Reader->getModuleManager().visit([&Mod](serialization::ModuleFile &M) {
2654     switch (M.Kind) {
2655     case serialization::MK_ImplicitModule:
2656     case serialization::MK_ExplicitModule:
2657     case serialization::MK_PrebuiltModule:
2658       return true; // skip dependencies.
2659     case serialization::MK_PCH:
2660       Mod = &M;
2661       return true; // found it.
2662     case serialization::MK_Preamble:
2663       return false; // look in dependencies.
2664     case serialization::MK_MainFile:
2665       return false; // look in dependencies.
2666     }
2667
2668     return true;
2669   });
2670   if (Mod)
2671     return Mod->File;
2672
2673   return std::nullopt;
2674 }
2675
2676 bool ASTUnit::isModuleFile() const {
2677   return isMainFileAST() && getLangOpts().isCompilingModule();
2678 }
2679
2680 InputKind ASTUnit::getInputKind() const {
2681   auto &LangOpts = getLangOpts();
2682
2683   Language Lang;
2684   if (LangOpts.OpenCL)
2685     Lang = Language::OpenCL;
2686   else if (LangOpts.CUDA)
2687     Lang = Language::CUDA;
2688   else if (LangOpts.RenderScript)
2689     Lang = Language::RenderScript;
2690   else if (LangOpts.CPlusPlus)
2691     Lang = LangOpts.ObjC ? Language::ObjCXX : Language::CXX;
2692   else
2693     Lang = LangOpts.ObjC ? Language::ObjC : Language::C;
2694
2695   InputKind::Format Fmt = InputKind::Source;
2696   if (LangOpts.getCompilingModule() == LangOptions::CMK_ModuleMap)
2697     Fmt = InputKind::ModuleMap;
2698
2699   // We don't know if input was preprocessed. Assume not.
2700   bool PP = false;
2701
2702   return InputKind(Lang, Fmt, PP);
2703 }
2704
2705 #ifndef NDEBUG
2706 ASTUnit::ConcurrencyState::ConcurrencyState() {
2707   Mutex = new std::recursive_mutex;
2708 }
2709
2710 ASTUnit::ConcurrencyState::~ConcurrencyState() {
2711   delete static_cast<std::recursive_mutex *>(Mutex);
2712 }
2713
2714 void ASTUnit::ConcurrencyState::start() {
2715   bool acquired = static_cast<std::recursive_mutex *>(Mutex)->try_lock();
2716   assert(acquired && "Concurrent access to ASTUnit!");
2717 }
2718
2719 void ASTUnit::ConcurrencyState::finish() {
2720   static_cast<std::recursive_mutex *>(Mutex)->unlock();
2721 }
2722
2723 #else // NDEBUG
2724
2725 ASTUnit::ConcurrencyState::ConcurrencyState() { Mutex = nullptr; }
2726 ASTUnit::ConcurrencyState::~ConcurrencyState() {}
2727 void ASTUnit::ConcurrencyState::start() {}
2728 void ASTUnit::ConcurrencyState::finish() {}
2729
2730 #endif // NDEBUG