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