1//===- DependencyScanningWorker.cpp - Thread-Safe Scanning Worker ---------===//
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#include "clang/DependencyScanning/DependencyScanningWorker.h"
10#include "clang/Basic/Diagnostic.h"
11#include "clang/Basic/DiagnosticFrontend.h"
12#include "clang/Basic/DiagnosticSerialization.h"
13#include "clang/DependencyScanning/DependencyActionController.h"
14#include "clang/DependencyScanning/DependencyConsumer.h"
15#include "clang/DependencyScanning/DependencyScanningFilesystem.h"
16#include "clang/Frontend/FrontendActions.h"
17#include "clang/Lex/Preprocessor.h"
18#include "clang/Sema/SemaOpenACC.h"
19#include "clang/Serialization/ObjectFilePCHContainerReader.h"
20#include "llvm/ADT/IntrusiveRefCntPtr.h"
21#include "llvm/ADT/ScopeExit.h"
22#include "llvm/Option/Option.h"
23#include "llvm/Support/AdvisoryLock.h"
24#include "llvm/Support/CrashRecoveryContext.h"
25#include "llvm/Support/VirtualFileSystem.h"
26#include "llvm/TargetParser/Host.h"
27#include <mutex>
28#include <thread>
29
30using namespace clang;
31using namespace dependencies;
32
33static bool checkHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
34 const HeaderSearchOptions &ExistingHSOpts,
35 DiagnosticsEngine *Diags,
36 const LangOptions &LangOpts) {
37 if (LangOpts.Modules) {
38 if (HSOpts.VFSOverlayFiles != ExistingHSOpts.VFSOverlayFiles) {
39 if (Diags) {
40 Diags->Report(DiagID: diag::warn_pch_vfsoverlay_mismatch);
41 auto VFSNote = [&](int Type, ArrayRef<std::string> VFSOverlays) {
42 if (VFSOverlays.empty()) {
43 Diags->Report(DiagID: diag::note_pch_vfsoverlay_empty) << Type;
44 } else {
45 std::string Files = llvm::join(R&: VFSOverlays, Separator: "\n");
46 Diags->Report(DiagID: diag::note_pch_vfsoverlay_files) << Type << Files;
47 }
48 };
49 VFSNote(0, HSOpts.VFSOverlayFiles);
50 VFSNote(1, ExistingHSOpts.VFSOverlayFiles);
51 }
52 }
53 }
54 return false;
55}
56namespace {
57using PrebuiltModuleFilesT = decltype(HeaderSearchOptions::PrebuiltModuleFiles);
58
59/// A listener that collects the imported modules and the input
60/// files. While visiting, collect vfsoverlays and file inputs that determine
61/// whether prebuilt modules fully resolve in stable directories.
62class PrebuiltModuleListener : public ASTReaderListener {
63public:
64 PrebuiltModuleListener(PrebuiltModuleFilesT &PrebuiltModuleFiles,
65 llvm::SmallVector<std::string> &NewModuleFiles,
66 PrebuiltModulesAttrsMap &PrebuiltModulesASTMap,
67 const HeaderSearchOptions &HSOpts,
68 const LangOptions &LangOpts, DiagnosticsEngine &Diags,
69 const ArrayRef<StringRef> StableDirs)
70 : PrebuiltModuleFiles(PrebuiltModuleFiles),
71 NewModuleFiles(NewModuleFiles),
72 PrebuiltModulesASTMap(PrebuiltModulesASTMap), ExistingHSOpts(HSOpts),
73 ExistingLangOpts(LangOpts), Diags(Diags), StableDirs(StableDirs) {}
74
75 bool needsImportVisitation() const override { return true; }
76 bool needsInputFileVisitation() override { return true; }
77 bool needsSystemInputFileVisitation() override { return true; }
78
79 /// Accumulate the modules are transitively depended on by the initial
80 /// prebuilt module.
81 void visitImport(StringRef ModuleName, StringRef Filename) override {
82 if (PrebuiltModuleFiles.insert(x: {ModuleName.str(), Filename.str()}).second)
83 NewModuleFiles.push_back(Elt: Filename.str());
84
85 auto PrebuiltMapEntry = PrebuiltModulesASTMap.try_emplace(Key: Filename);
86 PrebuiltModuleASTAttrs &PrebuiltModule = PrebuiltMapEntry.first->second;
87 if (PrebuiltMapEntry.second)
88 PrebuiltModule.setInStableDir(!StableDirs.empty());
89
90 if (auto It = PrebuiltModulesASTMap.find(Key: CurrentFile);
91 It != PrebuiltModulesASTMap.end() && CurrentFile != Filename)
92 PrebuiltModule.addDependent(ModuleFile: It->getKey());
93 }
94
95 /// For each input file discovered, check whether it's external path is in a
96 /// stable directory. Traversal is stopped if the current module is not
97 /// considered stable.
98 bool visitInputFileAsRequested(StringRef FilenameAsRequested,
99 StringRef Filename, bool isSystem,
100 bool isOverridden, time_t StoredTime,
101 bool isExplicitModule) override {
102 if (StableDirs.empty())
103 return false;
104 auto PrebuiltEntryIt = PrebuiltModulesASTMap.find(Key: CurrentFile);
105 if ((PrebuiltEntryIt == PrebuiltModulesASTMap.end()) ||
106 (!PrebuiltEntryIt->second.isInStableDir()))
107 return false;
108
109 PrebuiltEntryIt->second.setInStableDir(
110 isPathInStableDir(Directories: StableDirs, Input: Filename));
111 return PrebuiltEntryIt->second.isInStableDir();
112 }
113
114 /// Update which module that is being actively traversed.
115 void visitModuleFile(ModuleFileName Filename, serialization::ModuleKind Kind,
116 bool DirectlyImported) override {
117 // If the CurrentFile is not
118 // considered stable, update any of it's transitive dependents.
119 auto PrebuiltEntryIt = PrebuiltModulesASTMap.find(Key: CurrentFile);
120 if ((PrebuiltEntryIt != PrebuiltModulesASTMap.end()) &&
121 !PrebuiltEntryIt->second.isInStableDir())
122 PrebuiltEntryIt->second.updateDependentsNotInStableDirs(
123 PrebuiltModulesMap&: PrebuiltModulesASTMap);
124 CurrentFile = Filename.str();
125 }
126
127 /// Check the header search options for a given module when considering
128 /// if the module comes from stable directories.
129 bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
130 StringRef ModuleFilename, StringRef ContextHash,
131 bool Complain) override {
132
133 auto PrebuiltMapEntry = PrebuiltModulesASTMap.try_emplace(Key: CurrentFile);
134 PrebuiltModuleASTAttrs &PrebuiltModule = PrebuiltMapEntry.first->second;
135 if (PrebuiltMapEntry.second)
136 PrebuiltModule.setInStableDir(!StableDirs.empty());
137
138 if (PrebuiltModule.isInStableDir())
139 PrebuiltModule.setInStableDir(areOptionsInStableDir(Directories: StableDirs, HSOpts));
140
141 return false;
142 }
143
144 /// Accumulate vfsoverlays used to build these prebuilt modules.
145 bool ReadHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
146 bool Complain) override {
147
148 auto PrebuiltMapEntry = PrebuiltModulesASTMap.try_emplace(Key: CurrentFile);
149 PrebuiltModuleASTAttrs &PrebuiltModule = PrebuiltMapEntry.first->second;
150 if (PrebuiltMapEntry.second)
151 PrebuiltModule.setInStableDir(!StableDirs.empty());
152
153 PrebuiltModule.setVFS(
154 llvm::StringSet<>(llvm::from_range, HSOpts.VFSOverlayFiles));
155
156 return checkHeaderSearchPaths(
157 HSOpts, ExistingHSOpts, Diags: Complain ? &Diags : nullptr, LangOpts: ExistingLangOpts);
158 }
159
160private:
161 PrebuiltModuleFilesT &PrebuiltModuleFiles;
162 llvm::SmallVector<std::string> &NewModuleFiles;
163 PrebuiltModulesAttrsMap &PrebuiltModulesASTMap;
164 const HeaderSearchOptions &ExistingHSOpts;
165 const LangOptions &ExistingLangOpts;
166 DiagnosticsEngine &Diags;
167 std::string CurrentFile;
168 const ArrayRef<StringRef> StableDirs;
169};
170} // namespace
171
172/// Visit the given prebuilt module and collect all of the modules it
173/// transitively imports and contributing input files.
174static bool visitPrebuiltModule(StringRef PrebuiltModuleFilename,
175 CompilerInstance &CI,
176 PrebuiltModuleFilesT &ModuleFiles,
177 PrebuiltModulesAttrsMap &PrebuiltModulesASTMap,
178 DiagnosticsEngine &Diags,
179 const ArrayRef<StringRef> StableDirs) {
180 // List of module files to be processed.
181 llvm::SmallVector<std::string> Worklist;
182
183 PrebuiltModuleListener Listener(ModuleFiles, Worklist, PrebuiltModulesASTMap,
184 CI.getHeaderSearchOpts(), CI.getLangOpts(),
185 Diags, StableDirs);
186
187 Listener.visitModuleFile(Filename: ModuleFileName::makeExplicit(Name: PrebuiltModuleFilename),
188 Kind: serialization::MK_ExplicitModule,
189 /*DirectlyImported=*/true);
190 if (ASTReader::readASTFileControlBlock(
191 Filename: PrebuiltModuleFilename, FileMgr&: CI.getFileManager(), ModCache: CI.getModuleCache(),
192 PCHContainerRdr: CI.getPCHContainerReader(),
193 /*FindModuleFileExtensions=*/false, Listener,
194 /*ValidateDiagnosticOptions=*/false, ClientLoadCapabilities: ASTReader::ARR_OutOfDate))
195 return true;
196
197 while (!Worklist.empty()) {
198 // FIXME: This is assuming the PCH only refers to explicitly-built modules,
199 // which technically is not guaranteed. To remove the assumption, we'd need
200 // to also rework how the module files are handled to the scan, specifically
201 // change the values of HeaderSearchOptions::PrebuiltModuleFiles from plain
202 // paths to ModuleFileName.
203 Listener.visitModuleFile(Filename: ModuleFileName::makeExplicit(Name: Worklist.back()),
204 Kind: serialization::MK_ExplicitModule,
205 /*DirectlyImported=*/false);
206 if (ASTReader::readASTFileControlBlock(
207 Filename: Worklist.pop_back_val(), FileMgr&: CI.getFileManager(), ModCache: CI.getModuleCache(),
208 PCHContainerRdr: CI.getPCHContainerReader(),
209 /*FindModuleFileExtensions=*/false, Listener,
210 /*ValidateDiagnosticOptions=*/false))
211 return true;
212 }
213 return false;
214}
215
216/// Transform arbitrary file name into an object-like file name.
217static std::string makeObjFileName(StringRef FileName) {
218 SmallString<128> ObjFileName(FileName);
219 llvm::sys::path::replace_extension(path&: ObjFileName, extension: "o");
220 return std::string(ObjFileName);
221}
222
223/// Deduce the dependency target based on the output file and input files.
224static std::string
225deduceDepTarget(const std::string &OutputFile,
226 const SmallVectorImpl<FrontendInputFile> &InputFiles) {
227 if (OutputFile != "-")
228 return OutputFile;
229
230 if (InputFiles.empty() || !InputFiles.front().isFile())
231 return "clang-scan-deps\\ dependency";
232
233 return makeObjFileName(FileName: InputFiles.front().getFile());
234}
235
236// Clang implements -D and -U by splatting text into a predefines buffer. This
237// allows constructs such as `-DFඞ=3 "-D F\u{0D9E} 4 3 2”` to be accepted and
238// define the same macro, or adding C++ style comments before the macro name.
239//
240// This function checks that the first non-space characters in the macro
241// obviously form an identifier that can be uniqued on without lexing. Failing
242// to do this could lead to changing the final definition of a macro.
243//
244// We could set up a preprocessor and actually lex the name, but that's very
245// heavyweight for a situation that will almost never happen in practice.
246static std::optional<StringRef> getSimpleMacroName(StringRef Macro) {
247 StringRef Name = Macro.split(Separator: "=").first.ltrim(Chars: " \t");
248 std::size_t I = 0;
249
250 auto FinishName = [&]() -> std::optional<StringRef> {
251 StringRef SimpleName = Name.slice(Start: 0, End: I);
252 if (SimpleName.empty())
253 return std::nullopt;
254 return SimpleName;
255 };
256
257 for (; I != Name.size(); ++I) {
258 switch (Name[I]) {
259 case '(': // Start of macro parameter list
260 case ' ': // End of macro name
261 case '\t':
262 return FinishName();
263 case '_':
264 continue;
265 default:
266 if (llvm::isAlnum(C: Name[I]))
267 continue;
268 return std::nullopt;
269 }
270 }
271 return FinishName();
272}
273
274static void canonicalizeDefines(PreprocessorOptions &PPOpts) {
275 using MacroOpt = std::pair<StringRef, std::size_t>;
276 std::vector<MacroOpt> SimpleNames;
277 SimpleNames.reserve(n: PPOpts.Macros.size());
278 std::size_t Index = 0;
279 for (const auto &M : PPOpts.Macros) {
280 auto SName = getSimpleMacroName(Macro: M.first);
281 // Skip optimizing if we can't guarantee we can preserve relative order.
282 if (!SName)
283 return;
284 SimpleNames.emplace_back(args&: *SName, args&: Index);
285 ++Index;
286 }
287
288 llvm::stable_sort(Range&: SimpleNames, C: llvm::less_first());
289 // Keep the last instance of each macro name by going in reverse
290 auto NewEnd = std::unique(
291 first: SimpleNames.rbegin(), last: SimpleNames.rend(),
292 binary_pred: [](const MacroOpt &A, const MacroOpt &B) { return A.first == B.first; });
293 SimpleNames.erase(first: SimpleNames.begin(), last: NewEnd.base());
294
295 // Apply permutation.
296 decltype(PPOpts.Macros) NewMacros;
297 NewMacros.reserve(n: SimpleNames.size());
298 for (std::size_t I = 0, E = SimpleNames.size(); I != E; ++I) {
299 std::size_t OriginalIndex = SimpleNames[I].second;
300 // We still emit undefines here as they may be undefining a predefined macro
301 NewMacros.push_back(x: std::move(PPOpts.Macros[OriginalIndex]));
302 }
303 std::swap(x&: PPOpts.Macros, y&: NewMacros);
304}
305
306namespace {
307class ScanningDependencyDirectivesGetter : public DependencyDirectivesGetter {
308 DependencyScanningWorkerFilesystem *DepFS;
309
310public:
311 ScanningDependencyDirectivesGetter(FileManager &FileMgr) : DepFS(nullptr) {
312 FileMgr.getVirtualFileSystem().visit(Callback: [&](llvm::vfs::FileSystem &FS) {
313 auto *DFS = llvm::dyn_cast<DependencyScanningWorkerFilesystem>(Val: &FS);
314 if (DFS) {
315 assert(!DepFS && "Found multiple scanning VFSs");
316 DepFS = DFS;
317 }
318 });
319 assert(DepFS && "Did not find scanning VFS");
320 }
321
322 std::unique_ptr<DependencyDirectivesGetter>
323 cloneFor(FileManager &FileMgr) override {
324 return std::make_unique<ScanningDependencyDirectivesGetter>(args&: FileMgr);
325 }
326
327 std::optional<ArrayRef<dependency_directives_scan::Directive>>
328 operator()(FileEntryRef File) override {
329 return DepFS->getDirectiveTokens(Path: File.getName());
330 }
331};
332} // namespace
333
334/// Sanitize diagnostic options for dependency scan.
335static void sanitizeDiagOpts(DiagnosticOptions &DiagOpts) {
336 // Don't print 'X warnings and Y errors generated'.
337 DiagOpts.ShowCarets = false;
338 // Don't write out diagnostic file.
339 DiagOpts.DiagnosticSerializationFile.clear();
340 // Don't emit warnings except for scanning specific warnings.
341 // TODO: It would be useful to add a more principled way to ignore all
342 // warnings that come from source code. The issue is that we need to
343 // ignore warnings that could be surpressed by
344 // `#pragma clang diagnostic`, while still allowing some scanning
345 // warnings for things we're not ready to turn into errors yet.
346 // See `test/ClangScanDeps/diagnostic-pragmas.c` for an example.
347 llvm::erase_if(C&: DiagOpts.Warnings, P: [](StringRef Warning) {
348 return llvm::StringSwitch<bool>(Warning)
349 .Cases(CaseStrings: {"pch-vfs-diff", "error=pch-vfs-diff"}, Value: false)
350 .StartsWith(S: "no-error=", Value: false)
351 .Default(Value: true);
352 });
353}
354
355static std::unique_ptr<CompilerInvocation>
356createCompilerInvocation(ArrayRef<std::string> CommandLine,
357 DiagnosticsEngine &Diags) {
358 llvm::opt::ArgStringList Argv;
359 for (const std::string &Str : ArrayRef(CommandLine).drop_front())
360 Argv.push_back(Elt: Str.c_str());
361
362 auto Invocation = std::make_unique<CompilerInvocation>();
363 if (!CompilerInvocation::CreateFromArgs(Res&: *Invocation, CommandLineArgs: Argv, Diags)) {
364 // FIXME: Should we just go on like cc1_main does?
365 return nullptr;
366 }
367 return Invocation;
368}
369
370static void initializeScanCompilerInstance(
371 CompilerInstance &ScanInstance,
372 IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
373 DiagnosticConsumer *DiagConsumer, DependencyScanningService &Service,
374 IntrusiveRefCntPtr<DependencyScanningWorkerFilesystem> DepFS) {
375 ScanInstance.setBuildingModule(false);
376 ScanInstance.createVirtualFileSystem(BaseFS: FS, DC: DiagConsumer);
377 ScanInstance.createDiagnostics(Client: DiagConsumer, /*ShouldOwnClient=*/false);
378 if (!Service.getOpts().EmitWarnings)
379 ScanInstance.getDiagnostics().setIgnoreAllWarnings(true);
380 ScanInstance.createFileManager();
381 ScanInstance.createSourceManager();
382
383 // Use DepFS for getting the dependency directives if requested to do so.
384 if (Service.getOpts().Mode == ScanningMode::DependencyDirectivesScan)
385 ScanInstance.setDependencyDirectivesGetter(
386 std::make_unique<ScanningDependencyDirectivesGetter>(
387 args&: ScanInstance.getFileManager()));
388}
389
390static std::shared_ptr<CompilerInvocation>
391createScanCompilerInvocation(const CompilerInvocation &Invocation,
392 const DependencyScanningService &Service,
393 DependencyActionController &Controller) {
394 auto ScanInvocation = std::make_shared<CompilerInvocation>(args: Invocation);
395
396 sanitizeDiagOpts(DiagOpts&: ScanInvocation->getDiagnosticOpts());
397
398 ScanInvocation->getPreprocessorOpts().AllowPCHWithDifferentModulesCachePath =
399 true;
400
401 if (ScanInvocation->getHeaderSearchOpts().ModulesValidateOncePerBuildSession)
402 ScanInvocation->getHeaderSearchOpts().BuildSessionTimestamp =
403 Service.getOpts().BuildSessionTimestamp;
404
405 ScanInvocation->getFrontendOpts().DisableFree = false;
406 ScanInvocation->getFrontendOpts().GenerateGlobalModuleIndex = false;
407 ScanInvocation->getFrontendOpts().UseGlobalModuleIndex = false;
408 ScanInvocation->getFrontendOpts().GenReducedBMI = false;
409 ScanInvocation->getFrontendOpts().ModuleOutputPath.clear();
410 // This will prevent us compiling individual modules asynchronously since
411 // FileManager is not thread-safe, but it does improve performance for now.
412 ScanInvocation->getFrontendOpts().ModulesShareFileManager = true;
413 ScanInvocation->getHeaderSearchOpts().ModuleFormat = "raw";
414 ScanInvocation->getHeaderSearchOpts().ModulesIncludeVFSUsage =
415 any(Val: Service.getOpts().OptimizeArgs & ScanningOptimizations::VFS);
416
417 // Consider different header search and diagnostic options to create
418 // different modules. This avoids the unsound aliasing of module PCMs.
419 //
420 // TODO: Implement diagnostic bucketing to reduce the impact of strict
421 // context hashing.
422 ScanInvocation->getHeaderSearchOpts().ModulesStrictContextHash = true;
423 ScanInvocation->getHeaderSearchOpts().ModulesSerializeOnlyPreprocessor = true;
424 ScanInvocation->getHeaderSearchOpts().ModulesSkipDiagnosticOptions = true;
425 ScanInvocation->getHeaderSearchOpts().ModulesSkipHeaderSearchPaths = true;
426 ScanInvocation->getHeaderSearchOpts().ModulesSkipPragmaDiagnosticMappings =
427 true;
428 ScanInvocation->getHeaderSearchOpts().ModulesForceValidateUserHeaders = false;
429
430 // FIXME: Do this even with PCHs by marking the option as something like
431 // "preprocessor benign" in LangOptions.def so that it passes the
432 // compatibility checks in ASTReader.
433 if (ScanInvocation->getPreprocessorOpts().ImplicitPCHInclude.empty()) {
434 // Application extension only affects the handling of availability
435 // attributes, which cannot change the dependencies.
436 ScanInvocation->getLangOpts().AppExt = false;
437 }
438
439 // Ensure that the scanner does not create new dependency collectors,
440 // and thus won't write out the extra '.d' files to disk.
441 ScanInvocation->getDependencyOutputOpts() = {};
442
443 Controller.initializeScanInvocation(ScanInvocation&: *ScanInvocation);
444
445 return ScanInvocation;
446}
447
448static llvm::SmallVector<StringRef>
449getInitialStableDirs(const CompilerInstance &ScanInstance) {
450 // Create a collection of stable directories derived from the ScanInstance
451 // for determining whether module dependencies would fully resolve from
452 // those directories.
453 llvm::SmallVector<StringRef> StableDirs;
454 const StringRef Sysroot = ScanInstance.getHeaderSearchOpts().Sysroot;
455 if (!Sysroot.empty() && (llvm::sys::path::root_directory(path: Sysroot) != Sysroot))
456 StableDirs = {Sysroot, ScanInstance.getHeaderSearchOpts().ResourceDir};
457 return StableDirs;
458}
459
460static std::optional<PrebuiltModulesAttrsMap>
461computePrebuiltModulesASTMap(CompilerInstance &ScanInstance,
462 llvm::SmallVector<StringRef> &StableDirs) {
463 // Store a mapping of prebuilt module files and their properties like header
464 // search options. This will prevent the implicit build to create duplicate
465 // modules and will force reuse of the existing prebuilt module files
466 // instead.
467 PrebuiltModulesAttrsMap PrebuiltModulesASTMap;
468
469 if (!ScanInstance.getPreprocessorOpts().ImplicitPCHInclude.empty())
470 if (visitPrebuiltModule(
471 PrebuiltModuleFilename: ScanInstance.getPreprocessorOpts().ImplicitPCHInclude, CI&: ScanInstance,
472 ModuleFiles&: ScanInstance.getHeaderSearchOpts().PrebuiltModuleFiles,
473 PrebuiltModulesASTMap, Diags&: ScanInstance.getDiagnostics(), StableDirs))
474 return {};
475
476 return PrebuiltModulesASTMap;
477}
478
479static std::unique_ptr<DependencyOutputOptions>
480createDependencyOutputOptions(const CompilerInvocation &Invocation) {
481 auto Opts = std::make_unique<DependencyOutputOptions>(
482 args: Invocation.getDependencyOutputOpts());
483 // We need at least one -MT equivalent for the generator of make dependency
484 // files to work.
485 if (Opts->Targets.empty())
486 Opts->Targets = {deduceDepTarget(OutputFile: Invocation.getFrontendOpts().OutputFile,
487 InputFiles: Invocation.getFrontendOpts().Inputs)};
488 Opts->IncludeSystemHeaders = true;
489
490 return Opts;
491}
492
493static std::shared_ptr<ModuleDepCollector>
494initializeScanInstanceDependencyCollector(
495 CompilerInstance &ScanInstance,
496 std::unique_ptr<DependencyOutputOptions> DepOutputOpts,
497 DependencyScanningService &Service, CompilerInvocation &Inv,
498 DependencyActionController &Controller,
499 PrebuiltModulesAttrsMap PrebuiltModulesASTMap,
500 SmallVector<StringRef> &StableDirs) {
501 auto MDC = std::make_shared<ModuleDepCollector>(
502 args&: Service, args: std::move(DepOutputOpts), args&: ScanInstance, args&: Controller, args&: Inv,
503 args: std::move(PrebuiltModulesASTMap), args&: StableDirs);
504 ScanInstance.addDependencyCollector(Listener: MDC);
505 return MDC;
506}
507
508namespace {
509/// Manages (and terminates) the asynchronous compilation of modules.
510class AsyncModuleCompiles {
511 std::mutex Mutex;
512 bool Stop = false;
513 // FIXME: Have the service own a thread pool and use that instead.
514 std::vector<std::thread> Compiles;
515
516public:
517 /// Registers the module compilation, unless this instance is about to be
518 /// destroyed.
519 void add(llvm::unique_function<void()> Compile) {
520 std::lock_guard<std::mutex> Lock(Mutex);
521 if (!Stop)
522 Compiles.emplace_back(args: std::move(Compile));
523 }
524
525 ~AsyncModuleCompiles() {
526 {
527 std::lock_guard<std::mutex> Lock(Mutex);
528 Stop = true;
529 }
530 for (std::thread &Compile : Compiles)
531 Compile.join();
532 }
533};
534
535struct SingleModuleWithAsyncModuleCompiles : PreprocessOnlyAction {
536 DependencyScanningService &Service;
537 DependencyActionController &Controller;
538 AsyncModuleCompiles &Compiles;
539
540 SingleModuleWithAsyncModuleCompiles(DependencyScanningService &Service,
541 DependencyActionController &Controller,
542 AsyncModuleCompiles &Compiles)
543 : Service(Service), Controller(Controller), Compiles(Compiles) {}
544
545 bool BeginSourceFileAction(CompilerInstance &CI) override;
546};
547
548/// Runs the preprocessor on a TU with single-module-parse-mode and compiles
549/// modules asynchronously without blocking or importing them.
550struct SingleTUWithAsyncModuleCompiles : PreprocessOnlyAction {
551 DependencyScanningService &Service;
552 DependencyActionController &Controller;
553 AsyncModuleCompiles &Compiles;
554
555 SingleTUWithAsyncModuleCompiles(DependencyScanningService &Service,
556 DependencyActionController &Controller,
557 AsyncModuleCompiles &Compiles)
558 : Service(Service), Controller(Controller), Compiles(Compiles) {}
559
560 bool BeginSourceFileAction(CompilerInstance &CI) override;
561};
562
563/// The preprocessor callback that takes care of initiating an asynchronous
564/// module compilation if needed.
565struct AsyncModuleCompile : PPCallbacks {
566 CompilerInstance &CI;
567 DependencyScanningService &Service;
568 DependencyActionController &Controller;
569 AsyncModuleCompiles &Compiles;
570
571 AsyncModuleCompile(CompilerInstance &CI, DependencyScanningService &Service,
572 DependencyActionController &Controller,
573 AsyncModuleCompiles &Compiles)
574 : CI(CI), Service(Service), Controller(Controller), Compiles(Compiles) {}
575
576 void moduleLoadSkipped(Module *M) override {
577 M = M->getTopLevelModule();
578
579 HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
580 ModuleCache &ModCache = CI.getModuleCache();
581 ModuleFileName ModuleFileName = HS.getCachedModuleFileName(Module: M);
582
583 uint64_t Timestamp = ModCache.getModuleTimestamp(ModuleFilename: ModuleFileName);
584 // Someone else already built/validated the PCM.
585 if (Timestamp > CI.getHeaderSearchOpts().BuildSessionTimestamp)
586 return;
587
588 if (!CI.getASTReader())
589 CI.createASTReader();
590 SmallVector<ASTReader::ImportedModule, 0> Imported;
591 // Only calling ReadASTCore() to avoid the expensive eager deserialization
592 // of the clang::Module objects in ReadAST().
593 // FIXME: Consider doing this in the new thread depending on how expensive
594 // the read turns out to be.
595 switch (CI.getASTReader()->ReadASTCore(
596 FileName: ModuleFileName, Type: serialization::MK_ImplicitModule, ImportLoc: SourceLocation(),
597 ImportedBy: nullptr, Loaded&: Imported, ExpectedSize: {}, ExpectedModTime: {}, ExpectedSignature: {},
598 ClientLoadCapabilities: ASTReader::ARR_OutOfDate | ASTReader::ARR_Missing |
599 ASTReader::ARR_TreatModuleWithErrorsAsOutOfDate)) {
600 case ASTReader::Success:
601 // We successfully read a valid, up-to-date PCM.
602 // FIXME: This could update the timestamp. Regular calls to
603 // ASTReader::ReadAST() would do so unless they encountered corrupted
604 // AST block, corrupted extension block, or did not read the expected
605 // top-level module.
606 return;
607 case ASTReader::OutOfDate:
608 case ASTReader::Missing:
609 // The most interesting case.
610 break;
611 default:
612 // Let the regular scan diagnose this.
613 return;
614 }
615
616 auto Lock = ModCache.getLock(ModuleFilename: ModuleFileName);
617 bool Owned;
618 llvm::Error LockErr = Lock->tryLock().moveInto(Value&: Owned);
619 // Someone else is building the PCM right now.
620 if (!LockErr && !Owned)
621 return;
622 // We should build the PCM.
623 IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
624 llvm::makeIntrusiveRefCnt<DependencyScanningWorkerFilesystem>(
625 A&: Service, A: Service.getOpts().MakeVFS());
626 VFS = createVFSFromCompilerInvocation(CI: CI.getInvocation(),
627 Diags&: CI.getDiagnostics(), BaseFS: std::move(VFS));
628 auto DC = std::make_unique<DiagnosticConsumer>();
629 auto MC = makeInProcessModuleCache(Entries&: Service.getModuleCacheEntries(),
630 Logger&: Service.getLogger());
631 CompilerInstance::ThreadSafeCloneConfig CloneConfig(std::move(VFS), *DC,
632 std::move(MC));
633 auto ModCI1 = CI.cloneForModuleCompile(ImportLoc: SourceLocation(), Module: M, ModuleFileName,
634 ThreadSafeConfig: CloneConfig);
635 auto ModCI2 = CI.cloneForModuleCompile(ImportLoc: SourceLocation(), Module: M, ModuleFileName,
636 ThreadSafeConfig: CloneConfig);
637
638 auto ModController = Controller.clone();
639
640 // Note: This lock belongs to a module cache that might not outlive the
641 // thread. This works, because the in-process lock only refers to an object
642 // managed by the service, which does outlive the thread.
643 Compiles.add(Compile: [Lock = std::move(Lock), ModCI1 = std::move(ModCI1),
644 ModCI2 = std::move(ModCI2), DC = std::move(DC),
645 ModController = std::move(ModController), Service = &Service,
646 Compiles = &Compiles] {
647 llvm::CrashRecoveryContext CRC;
648 (void)CRC.RunSafely(Fn: [&] {
649 // Quickly discovers and compiles modules for the real scan below.
650 SingleModuleWithAsyncModuleCompiles Action1(*Service, *ModController,
651 *Compiles);
652 (void)ModCI1->ExecuteAction(Act&: Action1);
653 // The real scan below.
654 ModCI2->getPreprocessorOpts().SingleModuleParseMode = false;
655 GenerateModuleFromModuleMapAction Action2;
656 (void)ModCI2->ExecuteAction(Act&: Action2);
657 });
658 });
659 }
660};
661
662bool SingleModuleWithAsyncModuleCompiles::BeginSourceFileAction(
663 CompilerInstance &CI) {
664 CI.getInvocation().getPreprocessorOpts().SingleModuleParseMode = true;
665 CI.getPreprocessor().addPPCallbacks(
666 C: std::make_unique<AsyncModuleCompile>(args&: CI, args&: Service, args&: Controller, args&: Compiles));
667 return true;
668}
669
670bool SingleTUWithAsyncModuleCompiles::BeginSourceFileAction(
671 CompilerInstance &CI) {
672 CI.getInvocation().getPreprocessorOpts().SingleModuleParseMode = true;
673 CI.getPreprocessor().addPPCallbacks(
674 C: std::make_unique<AsyncModuleCompile>(args&: CI, args&: Service, args&: Controller, args&: Compiles));
675 return true;
676}
677} // namespace
678
679static void runTUModulePrescan(CompilerInstance &PrescanCI,
680 DependencyScanningService &Service,
681 DependencyActionController &Controller,
682 AsyncModuleCompiles &Compiles) {
683 SingleTUWithAsyncModuleCompiles Action(Service, Controller, Compiles);
684 (void)PrescanCI.ExecuteAction(Act&: Action);
685}
686
687namespace clang {
688namespace dependencies {
689
690std::unique_ptr<DiagnosticOptions>
691createScanningDiagOptions(ArrayRef<std::string> CommandLine) {
692 std::vector<const char *> CCommandLine(CommandLine.size(), nullptr);
693 llvm::transform(Range&: CommandLine, d_first: CCommandLine.begin(),
694 F: [](const std::string &Str) { return Str.c_str(); });
695 auto DiagOpts = CreateAndPopulateDiagOpts(Argv: CCommandLine);
696 sanitizeDiagOpts(DiagOpts&: *DiagOpts);
697 return DiagOpts;
698}
699
700class CompilerInstanceWithContext {
701 // Context
702 DependencyScanningWorker &Worker;
703 llvm::StringRef CWD;
704 std::vector<std::string> CommandLine;
705
706 // Context - compiler invocation
707 std::unique_ptr<CompilerInvocation> OriginalInvocation;
708
709 // Context - output options
710 std::unique_ptr<DependencyOutputOptions> OutputOpts;
711
712 // Context - stable directory handling
713 llvm::SmallVector<StringRef> StableDirs;
714 PrebuiltModulesAttrsMap PrebuiltModuleASTMap;
715
716 // Context - used by AsyncScan's prescan pass
717 IntrusiveRefCntPtr<llvm::vfs::FileSystem> ScanFS;
718
719 // Compiler Instance
720 std::unique_ptr<CompilerInstance> CIPtr;
721
722 // Source location offset.
723 int32_t SrcLocOffset = 0;
724
725 CompilerInstanceWithContext(DependencyScanningWorker &Worker, StringRef CWD,
726 ArrayRef<std::string> CMD)
727 : Worker(Worker), CWD(CWD), CommandLine(CMD.begin(), CMD.end()) {}
728
729 bool initialize(DependencyActionController &Controller,
730 DiagnosticsEngine &DiagEngine,
731 IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS) {
732 {
733 auto LogLine = Worker.Service.getLogger().log();
734 LogLine.logArray(Prefix: "init_compiler_instance_with_context:", Sep: " ",
735 Arr: CommandLine);
736 }
737
738 ScanFS = Worker.makeEffectiveVFS(WorkingDirectory: CWD, OverlayFS: std::move(OverlayFS));
739 OriginalInvocation = createCompilerInvocation(CommandLine, Diags&: DiagEngine);
740 if (!OriginalInvocation) {
741 DiagEngine.Report(DiagID: diag::err_fe_expected_compiler_job)
742 << llvm::join(R&: CommandLine, Separator: " ");
743 return false;
744 }
745
746 return initializeScanInstance(Controller, DiagConsumer: DiagEngine.getClient());
747 }
748
749 bool initializeScanInstance(DependencyActionController &Controller,
750 DiagnosticConsumer *DiagConsumer) {
751 assert(OriginalInvocation && ScanFS &&
752 "OriginalInvocation and ScanFS must be set before this call");
753
754 if (any(Val: Worker.Service.getOpts().OptimizeArgs &
755 ScanningOptimizations::Macros))
756 canonicalizeDefines(PPOpts&: OriginalInvocation->getPreprocessorOpts());
757
758 // Create the CompilerInstance.
759 std::shared_ptr<ModuleCache> ModCache = makeInProcessModuleCache(
760 Entries&: Worker.Service.getModuleCacheEntries(), Logger&: Worker.Service.getLogger());
761 CIPtr = std::make_unique<CompilerInstance>(
762 args: createScanCompilerInvocation(Invocation: *OriginalInvocation, Service: Worker.Service,
763 Controller),
764 args&: Worker.PCHContainerOps, args: std::move(ModCache));
765 auto &CI = *CIPtr;
766
767 initializeScanCompilerInstance(ScanInstance&: CI, FS: ScanFS, DiagConsumer, Service&: Worker.Service,
768 DepFS: Worker.DepFS);
769
770 StableDirs = getInitialStableDirs(ScanInstance: CI);
771 auto MaybePrebuiltModulesASTMap =
772 computePrebuiltModulesASTMap(ScanInstance&: CI, StableDirs);
773 if (!MaybePrebuiltModulesASTMap)
774 return false;
775
776 PrebuiltModuleASTMap = std::move(*MaybePrebuiltModulesASTMap);
777 OutputOpts = createDependencyOutputOptions(Invocation: *OriginalInvocation);
778
779 // We do not create the target in initializeScanCompilerInstance because
780 // setting it here is unique for by-name lookups. We create the target only
781 // once here, and the information is reused for all computeDependencies
782 // calls. We do not need to call createTarget explicitly if we go through
783 // CompilerInstance::ExecuteAction to perform scanning.
784 return CI.createTarget();
785 }
786
787 bool prescanModulesAsync(AsyncModuleCompiles &Compiles,
788 DependencyActionController &Controller) {
789 auto ModCache = makeInProcessModuleCache(
790 Entries&: Worker.Service.getModuleCacheEntries(), Logger&: Worker.Service.getLogger());
791 CompilerInstance PrescanCI(
792 std::make_shared<CompilerInvocation>(args&: CIPtr->getInvocation()),
793 Worker.PCHContainerOps, std::move(ModCache));
794
795 DiagnosticConsumer DiagConsumer;
796 initializeScanCompilerInstance(ScanInstance&: PrescanCI, FS: ScanFS, DiagConsumer: &DiagConsumer,
797 Service&: Worker.Service, DepFS: Worker.DepFS);
798
799 // FIXME: reuse the StableDirs/PrebuiltModuleASTMap computed in
800 // initialize().
801 SmallVector<StringRef> PrescanStableDirs = getInitialStableDirs(ScanInstance: PrescanCI);
802 if (!computePrebuiltModulesASTMap(ScanInstance&: PrescanCI, StableDirs&: PrescanStableDirs))
803 return false;
804
805 if (PrescanCI.getFrontendOpts().ProgramAction == frontend::GeneratePCH)
806 PrescanCI.getLangOpts().CompilingPCH = true;
807
808 runTUModulePrescan(PrescanCI, Service&: Worker.Service, Controller, Compiles);
809 return true;
810 }
811
812public:
813 static std::optional<CompilerInstanceWithContext>
814 initializeFromCC1Commandline(
815 DependencyScanningWorker &Worker, StringRef CWD,
816 ArrayRef<std::string> CC1CommandLine, DiagnosticsEngine &DiagEngine,
817 IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS,
818 DependencyActionController &Controller) {
819 CompilerInstanceWithContext CIWC(Worker, CWD, CC1CommandLine);
820 if (!CIWC.initialize(Controller, DiagEngine, OverlayFS: std::move(OverlayFS)))
821 return std::nullopt;
822 return std::move(CIWC);
823 }
824
825 bool computeDependencies(StringRef ModuleName, DependencyConsumer &Consumer,
826 DependencyActionController &Controller) {
827 Worker.Service.getLogger().log() << "start scan_by_name: " << ModuleName;
828 llvm::scope_exit ExitLogging([&] {
829 Worker.Service.getLogger().log() << "finish scan_by_name: " << ModuleName;
830 });
831 if (SrcLocOffset >= DependencyScanningWorker::MaxNumOfByNameQueries)
832 llvm::report_fatal_error(reason: "exceeded maximum by-name scans for worker");
833
834 assert(CIPtr && "CIPtr must be initialized before calling this method");
835 auto &CI = *CIPtr;
836
837 // We need to reset the diagnostics, so that the diagnostics issued
838 // during a previous computeDependencies call do not affect the current
839 // call. If we do not reset, we may inherit fatal errors from a previous
840 // call.
841 CI.getDiagnostics().Reset();
842
843 // We create this cleanup object because computeDependencies may exit
844 // early with errors.
845 llvm::scope_exit CleanUp([&]() {
846 CI.clearDependencyCollectors();
847 // The preprocessor may not be created at the entry of this method,
848 // but it must have been created when this method returns, whether
849 // there are errors during scanning or not.
850 CI.getPreprocessor().removePPCallbacks();
851 });
852
853 auto MDC = initializeScanInstanceDependencyCollector(
854 ScanInstance&: CI, DepOutputOpts: std::make_unique<DependencyOutputOptions>(args&: *OutputOpts),
855 Service&: Worker.Service,
856 /* The MDC's constructor makes a copy of the OriginalInvocation, so
857 we can pass it in without worrying that it might be changed across
858 invocations of computeDependencies. */
859 Inv&: *OriginalInvocation, Controller, PrebuiltModulesASTMap: PrebuiltModuleASTMap, StableDirs);
860
861 CompilerInvocation ModuleInvocation(*OriginalInvocation);
862 if (!Controller.initialize(ScanInstance&: CI, NewInvocation&: ModuleInvocation))
863 return false;
864
865 if (!SrcLocOffset) {
866 // When SrcLocOffset is zero, we are at the beginning of the fake source
867 // file. In this case, we call BeginSourceFile to initialize.
868 std::unique_ptr<FrontendAction> Action =
869 std::make_unique<PreprocessOnlyAction>();
870 auto *InputFile = CI.getFrontendOpts().Inputs.begin();
871 bool ActionBeginSucceeded = Action->BeginSourceFile(CI, Input: *InputFile);
872 assert(ActionBeginSucceeded && "Action BeginSourceFile must succeed");
873 (void)ActionBeginSucceeded;
874 }
875
876 Preprocessor &PP = CI.getPreprocessor();
877 SourceManager &SM = PP.getSourceManager();
878 FileID MainFileID = SM.getMainFileID();
879 SourceLocation FileStart = SM.getLocForStartOfFile(FID: MainFileID);
880 SourceLocation IDLocation = FileStart.getLocWithOffset(Offset: SrcLocOffset);
881 PPCallbacks *CB = nullptr;
882 if (!SrcLocOffset) {
883 // We need to call EnterSourceFile when SrcLocOffset is zero to initialize
884 // the preprocessor.
885 bool PPFailed = PP.EnterSourceFile(FID: MainFileID, Dir: nullptr, Loc: SourceLocation());
886 assert(!PPFailed && "Preprocess must be able to enter the main file.");
887 (void)PPFailed;
888 CB = MDC->getPPCallbacks();
889 } else {
890 // When SrcLocOffset is non-zero, the preprocessor has already been
891 // initialized through a previous call of computeDependencies. We want to
892 // preserve the PP's state, hence we do not call EnterSourceFile again.
893 MDC->attachToPreprocessor(PP);
894 CB = MDC->getPPCallbacks();
895
896 FileID PrevFID;
897 SrcMgr::CharacteristicKind FileType =
898 SM.getFileCharacteristic(Loc: IDLocation);
899 CB->LexedFileChanged(FID: MainFileID,
900 Reason: PPChainedCallbacks::LexedFileChangeReason::EnterFile,
901 FileType, PrevFID, Loc: IDLocation);
902 }
903
904 // FIXME: Scan modules asynchronously here as well.
905
906 SrcLocOffset++;
907 SmallVector<IdentifierLoc, 2> Path;
908 IdentifierInfo *ModuleID = PP.getIdentifierInfo(Name: ModuleName);
909 Path.emplace_back(Args&: IDLocation, Args&: ModuleID);
910 auto ModResult = CI.loadModule(ImportLoc: IDLocation, Path, Visibility: Module::Hidden, IsInclusionDirective: false);
911
912 assert(CB && "Must have PPCallbacks after module loading");
913 CB->moduleImport(ImportLoc: SourceLocation(), Path, Imported: ModResult);
914
915 if (!ModResult)
916 return false;
917
918 if (CI.getDiagnostics().hasErrorOccurred())
919 return false;
920
921 MDC->run(Consumer);
922 MDC->applyDiscoveredDependencies(CI&: ModuleInvocation);
923
924 bool Success = ModuleInvocation.withCowRef<bool>(
925 Fn: [&](CowCompilerInvocation &CowModuleInvocation) {
926 return Controller.finalize(ScanInstance&: CI, NewInvocation&: CowModuleInvocation);
927 });
928 if (!Success)
929 return false;
930
931 Consumer.handleBuildCommand(
932 Cmd: {.Executable: CommandLine[0], .Arguments: ModuleInvocation.getCC1CommandLine()});
933
934 return true;
935 }
936
937 std::shared_ptr<ModuleDepCollector>
938 scanTranslationUnit(DependencyConsumer &Consumer,
939 DependencyActionController &Controller) {
940 assert(CIPtr && "CIPtr must be initialized before calling this method");
941 auto &CI = *CIPtr;
942
943 std::optional<AsyncModuleCompiles> AsyncCompiles;
944 if (Worker.Service.getOpts().AsyncScanModules) {
945 AsyncCompiles.emplace();
946 if (!prescanModulesAsync(Compiles&: *AsyncCompiles, Controller))
947 return nullptr;
948 }
949
950 auto MDC = initializeScanInstanceDependencyCollector(
951 ScanInstance&: CI, DepOutputOpts: std::make_unique<DependencyOutputOptions>(args&: *OutputOpts),
952 Service&: Worker.Service, Inv&: *OriginalInvocation, Controller, PrebuiltModulesASTMap: PrebuiltModuleASTMap,
953 StableDirs);
954
955 if (CI.getDiagnostics().hasErrorOccurred())
956 return nullptr;
957
958 if (!Controller.initialize(ScanInstance&: CI, NewInvocation&: *OriginalInvocation))
959 return nullptr;
960
961 ReadPCHAndPreprocessAction Action;
962 if (!CI.ExecuteAction(Act&: Action))
963 return nullptr;
964
965 MDC->run(Consumer);
966 if (!applyAndReport(MDC&: *MDC, ModuleInvocation&: *OriginalInvocation, Consumer, Controller,
967 Executable: CommandLine[0]))
968 return nullptr;
969 return MDC;
970 }
971
972 bool applyAndReport(ModuleDepCollector &MDC,
973 CompilerInvocation &ModuleInvocation,
974 DependencyConsumer &Consumer,
975 DependencyActionController &Controller,
976 StringRef Executable) {
977 MDC.applyDiscoveredDependencies(CI&: ModuleInvocation);
978 bool Success = ModuleInvocation.withCowRef<bool>(
979 Fn: [&](CowCompilerInvocation &CowModuleInvocation) {
980 return Controller.finalize(ScanInstance&: *CIPtr, NewInvocation&: CowModuleInvocation);
981 });
982 if (!Success)
983 return false;
984 Consumer.handleBuildCommand(
985 Cmd: {.Executable: Executable.str(), .Arguments: ModuleInvocation.getCC1CommandLine()});
986 return true;
987 }
988};
989} // namespace dependencies
990} // namespace clang
991
992DependencyScanningWorker::DependencyScanningWorker(
993 DependencyScanningService &Service)
994 : Service(Service) {
995 PCHContainerOps = std::make_shared<PCHContainerOperations>();
996 // We need to read object files from PCH built outside the scanner.
997 PCHContainerOps->registerReader(
998 Reader: std::make_unique<ObjectFilePCHContainerReader>());
999 // The scanner itself writes only raw ast files.
1000 PCHContainerOps->registerWriter(Writer: std::make_unique<RawPCHContainerWriter>());
1001
1002 auto BaseFS = Service.getOpts().MakeVFS();
1003
1004 if (Service.getOpts().TraceVFS) {
1005 TracingFS = llvm::makeIntrusiveRefCnt<llvm::vfs::TracingFileSystem>(
1006 A: std::move(BaseFS));
1007 BaseFS = TracingFS;
1008 }
1009
1010 DepFS = llvm::makeIntrusiveRefCnt<DependencyScanningWorkerFilesystem>(
1011 A&: Service, A: std::move(BaseFS));
1012}
1013
1014DependencyScanningWorker::~DependencyScanningWorker() = default;
1015
1016IntrusiveRefCntPtr<llvm::vfs::FileSystem>
1017DependencyScanningWorker::makeEffectiveVFS(
1018 StringRef WorkingDirectory,
1019 IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS) const {
1020 IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS = DepFS;
1021 if (OverlayFS) {
1022 auto NewFS =
1023 llvm::makeIntrusiveRefCnt<llvm::vfs::OverlayFileSystem>(A: std::move(FS));
1024 NewFS->pushOverlay(FS: std::move(OverlayFS));
1025 FS = std::move(NewFS);
1026 }
1027 FS->setCurrentWorkingDirectory(WorkingDirectory);
1028 return FS;
1029}
1030
1031bool DependencyScanningWorker::computeDependencies(
1032 StringRef WorkingDirectory, ArrayRef<ArrayRef<std::string>> CommandLines,
1033 DependencyConsumer &DepConsumer, DependencyActionController &Controller,
1034 DiagnosticConsumer &DiagConsumer,
1035 IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS) {
1036 auto FS = makeEffectiveVFS(WorkingDirectory, OverlayFS);
1037
1038 bool Scanned = false;
1039 std::shared_ptr<ModuleDepCollector> MDC;
1040 std::optional<CompilerInstanceWithContext> CIWC;
1041
1042 const bool Success = llvm::all_of(Range&: CommandLines, P: [&](const auto &Cmd) {
1043 if (StringRef(Cmd[1]) != "-cc1") {
1044 // Non-clang command. Just pass through to the dependency consumer.
1045 DepConsumer.handleBuildCommand(
1046 Cmd: {Cmd.front(), {Cmd.begin() + 1, Cmd.end()}});
1047 return true;
1048 }
1049
1050 Service.getLogger().log().logArray("starting scanning command:", " ", Cmd);
1051 llvm::scope_exit ExitLogging([&] {
1052 Service.getLogger().log().logArray("finished scanning command:", " ",
1053 Cmd);
1054 });
1055
1056 auto DiagOpts = createScanningDiagOptions(Cmd);
1057 auto DiagEngine =
1058 CompilerInstance::createDiagnostics(*FS, *DiagOpts, &DiagConsumer,
1059 /*ShouldOwnClient=*/false);
1060 if (!Scanned) {
1061 // Scanning runs once for the first -cc1 invocation in a chain of driver
1062 // jobs.
1063 // For any dependent jobs, reuse the scanning result and just update the
1064 // new invocation.
1065 // FIXME: to support multi-arch builds, each arch requires a separate
1066 // scan.
1067 Scanned = true;
1068 auto Result = CompilerInstanceWithContext::initializeFromCC1Commandline(
1069 Worker&: *this, CWD: WorkingDirectory, CC1CommandLine: Cmd, DiagEngine&: *DiagEngine, OverlayFS, Controller);
1070 if (!Result)
1071 return false;
1072 CIWC.emplace(std::move(*Result));
1073 MDC = CIWC->scanTranslationUnit(Consumer&: DepConsumer, Controller);
1074 return MDC != nullptr;
1075 }
1076
1077 auto Invocation = createCompilerInvocation(Cmd, *DiagEngine);
1078 if (!Invocation)
1079 return false;
1080
1081 // The first cc1 is canonicalized in initializeScanInstance; each sibling
1082 // invocation must likewise be canonicalized before its cc1 command line is
1083 // emitted. This is mostly relevant for multi-arch jobs where we currently
1084 // do not do re-scans.
1085 if (any(Val: Service.getOpts().OptimizeArgs & ScanningOptimizations::Macros))
1086 canonicalizeDefines(Invocation->getPreprocessorOpts());
1087
1088 assert(CIWC && "Must have an initialized CIWC");
1089 return CIWC->applyAndReport(MDC&: *MDC, ModuleInvocation&: *Invocation, Consumer&: DepConsumer, Controller,
1090 Executable: Cmd.front());
1091 });
1092
1093 return Success && Scanned;
1094}
1095
1096bool DependencyScanningWorker::computeDependenciesByName(
1097 StringRef CWD, ArrayRef<std::string> CC1CommandLine,
1098 IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS,
1099 DiagnosticConsumer &DiagConsumer, DependencyActionController &Controller,
1100 llvm::function_ref<std::optional<std::string>()> getNextName,
1101 DependencyConsumer &DepConsumer) {
1102 auto FS = makeEffectiveVFS(WorkingDirectory: CWD, OverlayFS);
1103 auto DiagOpts = createScanningDiagOptions(CommandLine: CC1CommandLine);
1104 auto DiagEngine =
1105 CompilerInstance::createDiagnostics(VFS&: *FS, Opts&: *DiagOpts, Client: &DiagConsumer,
1106 /*ShouldOwnClient=*/false);
1107 std::optional<CompilerInstanceWithContext> CIWC =
1108 CompilerInstanceWithContext::initializeFromCC1Commandline(
1109 Worker&: *this, CWD, CC1CommandLine, DiagEngine&: *DiagEngine, OverlayFS: std::move(OverlayFS),
1110 Controller);
1111 if (!CIWC)
1112 return false;
1113
1114 bool AllScansSucceeded = true;
1115 while (std::optional<std::string> NextName = getNextName()) {
1116 bool Success =
1117 CIWC->computeDependencies(ModuleName: *NextName, Consumer&: DepConsumer, Controller);
1118 DepConsumer.finishQuery(ModuleName: *NextName, Success);
1119 AllScansSucceeded = AllScansSucceeded && Success;
1120 }
1121 return AllScansSucceeded;
1122}
1123