1//===--- CrossTranslationUnit.cpp - -----------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the CrossTranslationUnit interface.
10//
11//===----------------------------------------------------------------------===//
12#include "clang/CrossTU/CrossTranslationUnit.h"
13#include "clang/AST/ASTImporter.h"
14#include "clang/AST/Decl.h"
15#include "clang/AST/ParentMapContext.h"
16#include "clang/Basic/TargetInfo.h"
17#include "clang/CrossTU/CrossTUDiagnostic.h"
18#include "clang/Frontend/ASTUnit.h"
19#include "clang/Frontend/CompilerInstance.h"
20#include "clang/Frontend/TextDiagnosticPrinter.h"
21#include "clang/Index/USRGeneration.h"
22#include "llvm/ADT/Statistic.h"
23#include "llvm/Option/ArgList.h"
24#include "llvm/Support/ErrorHandling.h"
25#include "llvm/Support/ManagedStatic.h"
26#include "llvm/Support/Path.h"
27#include "llvm/Support/YAMLParser.h"
28#include "llvm/Support/raw_ostream.h"
29#include "llvm/TargetParser/Triple.h"
30#include <algorithm>
31#include <fstream>
32#include <optional>
33#include <sstream>
34#include <tuple>
35
36namespace clang {
37namespace cross_tu {
38
39namespace {
40
41#define DEBUG_TYPE "CrossTranslationUnit"
42STATISTIC(NumGetCTUCalled, "The # of getCTUDefinition function called");
43STATISTIC(
44 NumNotInOtherTU,
45 "The # of getCTUDefinition called but the function is not in any other TU");
46STATISTIC(NumGetCTUSuccess,
47 "The # of getCTUDefinition successfully returned the "
48 "requested function's body");
49STATISTIC(NumUnsupportedNodeFound, "The # of imports when the ASTImporter "
50 "encountered an unsupported AST Node");
51STATISTIC(NumNameConflicts, "The # of imports when the ASTImporter "
52 "encountered an ODR error");
53STATISTIC(NumTripleMismatch, "The # of triple mismatches");
54STATISTIC(NumLangMismatch, "The # of language mismatches");
55STATISTIC(NumLangDialectMismatch, "The # of language dialect mismatches");
56STATISTIC(NumASTLoadThresholdReached,
57 "The # of ASTs not loaded because of threshold");
58
59// Same as Triple's equality operator, but we check a field only if that is
60// known in both instances.
61bool hasEqualKnownFields(const llvm::Triple &Lhs, const llvm::Triple &Rhs) {
62 using llvm::Triple;
63 if (Lhs.getArch() != Triple::UnknownArch &&
64 Rhs.getArch() != Triple::UnknownArch && Lhs.getArch() != Rhs.getArch())
65 return false;
66 if (Lhs.getSubArch() != Triple::NoSubArch &&
67 Rhs.getSubArch() != Triple::NoSubArch &&
68 Lhs.getSubArch() != Rhs.getSubArch())
69 return false;
70 if (Lhs.getVendor() != Triple::UnknownVendor &&
71 Rhs.getVendor() != Triple::UnknownVendor &&
72 Lhs.getVendor() != Rhs.getVendor())
73 return false;
74 if (!Lhs.isOSUnknown() && !Rhs.isOSUnknown() &&
75 Lhs.getOS() != Rhs.getOS())
76 return false;
77 if (Lhs.getEnvironment() != Triple::UnknownEnvironment &&
78 Rhs.getEnvironment() != Triple::UnknownEnvironment &&
79 Lhs.getEnvironment() != Rhs.getEnvironment())
80 return false;
81 if (Lhs.getObjectFormat() != Triple::UnknownObjectFormat &&
82 Rhs.getObjectFormat() != Triple::UnknownObjectFormat &&
83 Lhs.getObjectFormat() != Rhs.getObjectFormat())
84 return false;
85 return true;
86}
87
88// FIXME: This class is will be removed after the transition to llvm::Error.
89class IndexErrorCategory : public std::error_category {
90public:
91 const char *name() const noexcept override { return "clang.index"; }
92
93 std::string message(int Condition) const override {
94 switch (static_cast<index_error_code>(Condition)) {
95 case index_error_code::success:
96 // There should not be a success error. Jump to unreachable directly.
97 // Add this case to make the compiler stop complaining.
98 break;
99 case index_error_code::unspecified:
100 return "An unknown error has occurred.";
101 case index_error_code::missing_index_file:
102 return "The index file is missing.";
103 case index_error_code::invalid_index_format:
104 return "Invalid index file format.";
105 case index_error_code::multiple_definitions:
106 return "Multiple definitions in the index file.";
107 case index_error_code::missing_definition:
108 return "Missing definition from the index file.";
109 case index_error_code::failed_import:
110 return "Failed to import the definition.";
111 case index_error_code::failed_to_get_external_ast:
112 return "Failed to load external AST source.";
113 case index_error_code::failed_to_generate_usr:
114 return "Failed to generate USR.";
115 case index_error_code::triple_mismatch:
116 return "Triple mismatch";
117 case index_error_code::lang_mismatch:
118 return "Language mismatch";
119 case index_error_code::lang_dialect_mismatch:
120 return "Language dialect mismatch";
121 case index_error_code::load_threshold_reached:
122 return "Load threshold reached";
123 case index_error_code::invocation_list_ambiguous:
124 return "Invocation list file contains multiple references to the same "
125 "source file.";
126 case index_error_code::invocation_list_file_not_found:
127 return "Invocation list file is not found.";
128 case index_error_code::invocation_list_empty:
129 return "Invocation list file is empty.";
130 case index_error_code::invocation_list_wrong_format:
131 return "Invocation list file is in wrong format.";
132 case index_error_code::invocation_list_lookup_unsuccessful:
133 return "Invocation list file does not contain the requested source file.";
134 }
135 llvm_unreachable("Unrecognized index_error_code.");
136 }
137};
138
139static llvm::ManagedStatic<IndexErrorCategory> Category;
140} // end anonymous namespace
141
142char IndexError::ID;
143
144void IndexError::log(raw_ostream &OS) const {
145 OS << Category->message(Condition: static_cast<int>(Code)) << '\n';
146}
147
148std::error_code IndexError::convertToErrorCode() const {
149 return std::error_code(static_cast<int>(Code), *Category);
150}
151
152/// Parse one line of the input CTU index file.
153///
154/// @param[in] LineRef The input CTU index item in format
155/// "<USR-Length>:<USR> <File-Path>".
156/// @param[out] LookupName The lookup name in format "<USR-Length>:<USR>".
157/// @param[out] FilePath The file path "<File-Path>".
158static bool parseCrossTUIndexItem(StringRef LineRef, StringRef &LookupName,
159 StringRef &FilePath) {
160 // `LineRef` is "<USR-Length>:<USR> <File-Path>" now.
161
162 size_t USRLength = 0;
163 if (LineRef.consumeInteger(Radix: 10, Result&: USRLength))
164 return false;
165 assert(USRLength && "USRLength should be greater than zero.");
166
167 if (!LineRef.consume_front(Prefix: ":"))
168 return false;
169
170 // `LineRef` is now just "<USR> <File-Path>".
171
172 // Check LookupName length out of bound and incorrect delimiter.
173 if (USRLength >= LineRef.size() || ' ' != LineRef[USRLength])
174 return false;
175
176 LookupName = LineRef.substr(Start: 0, N: USRLength);
177 FilePath = LineRef.substr(Start: USRLength + 1);
178 return true;
179}
180
181llvm::Expected<llvm::StringMap<std::string>>
182parseCrossTUIndex(StringRef IndexPath) {
183 std::ifstream ExternalMapFile{std::string(IndexPath)};
184 if (!ExternalMapFile)
185 return llvm::make_error<IndexError>(Args: index_error_code::missing_index_file,
186 Args: IndexPath.str());
187
188 llvm::StringMap<std::string> Result;
189 std::string Line;
190 unsigned LineNo = 1;
191 while (std::getline(is&: ExternalMapFile, str&: Line)) {
192 // Split lookup name and file path
193 StringRef LookupName, FilePathInIndex;
194 if (!parseCrossTUIndexItem(LineRef: Line, LookupName, FilePath&: FilePathInIndex))
195 return llvm::make_error<IndexError>(
196 Args: index_error_code::invalid_index_format, Args: IndexPath.str(), Args&: LineNo);
197
198 // Store paths with posix-style directory separator.
199 SmallString<32> FilePath(FilePathInIndex);
200 llvm::sys::path::native(path&: FilePath, style: llvm::sys::path::Style::posix);
201
202 bool InsertionOccured;
203 std::tie(args: std::ignore, args&: InsertionOccured) =
204 Result.try_emplace(Key: LookupName, Args: FilePath.begin(), Args: FilePath.end());
205 if (!InsertionOccured)
206 return llvm::make_error<IndexError>(
207 Args: index_error_code::multiple_definitions, Args: IndexPath.str(), Args&: LineNo);
208
209 ++LineNo;
210 }
211 return Result;
212}
213
214std::string
215createCrossTUIndexString(const llvm::StringMap<std::string> &Index) {
216 std::ostringstream Result;
217 for (const auto &E : Index)
218 Result << E.getKey().size() << ':' << E.getKey().str() << ' '
219 << E.getValue() << '\n';
220 return Result.str();
221}
222
223bool shouldImport(const VarDecl *VD, const ASTContext &ACtx) {
224 CanQualType CT = ACtx.getCanonicalType(T: VD->getType());
225 return CT.isConstQualified() && VD->getType().isTrivialType(Context: ACtx);
226}
227
228static bool hasBodyOrInit(const FunctionDecl *D, const FunctionDecl *&DefD) {
229 return D->hasBody(Definition&: DefD);
230}
231static bool hasBodyOrInit(const VarDecl *D, const VarDecl *&DefD) {
232 return D->getAnyInitializer(D&: DefD);
233}
234template <typename T> static bool hasBodyOrInit(const T *D) {
235 const T *Unused;
236 return hasBodyOrInit(D, Unused);
237}
238
239CrossTranslationUnitContext::CrossTranslationUnitContext(CompilerInstance &CI)
240 : Context(CI.getASTContext()), ASTStorage(CI) {}
241
242CrossTranslationUnitContext::~CrossTranslationUnitContext() {}
243
244std::optional<std::string>
245CrossTranslationUnitContext::getLookupName(const NamedDecl *ND) {
246 SmallString<128> DeclUSR;
247 bool Ret = index::generateUSRForDecl(D: ND, Buf&: DeclUSR);
248 if (Ret)
249 return {};
250 return std::string(DeclUSR);
251}
252
253/// Recursively visits the decls of a DeclContext, and returns one with the
254/// given USR.
255template <typename T>
256const T *
257CrossTranslationUnitContext::findDefInDeclContext(const DeclContext *DC,
258 StringRef LookupName) {
259 assert(DC && "Declaration Context must not be null");
260 for (const Decl *D : DC->decls()) {
261 const auto *SubDC = dyn_cast<DeclContext>(Val: D);
262 if (SubDC)
263 if (const auto *ND = findDefInDeclContext<T>(SubDC, LookupName))
264 return ND;
265
266 const auto *ND = dyn_cast<T>(D);
267 const T *ResultDecl;
268 if (!ND || !hasBodyOrInit(ND, ResultDecl))
269 continue;
270 std::optional<std::string> ResultLookupName = getLookupName(ND: ResultDecl);
271 if (!ResultLookupName || *ResultLookupName != LookupName)
272 continue;
273 return ResultDecl;
274 }
275 return nullptr;
276}
277
278template <typename T>
279llvm::Expected<const T *> CrossTranslationUnitContext::getCrossTUDefinitionImpl(
280 const T *D, StringRef CrossTUDir, StringRef IndexName,
281 bool DisplayCTUProgress) {
282 assert(D && "D is missing, bad call to this function!");
283 assert(!hasBodyOrInit(D) &&
284 "D has a body or init in current translation unit!");
285 ++NumGetCTUCalled;
286 const std::optional<std::string> LookupName = getLookupName(ND: D);
287 if (!LookupName)
288 return llvm::make_error<IndexError>(
289 Args: index_error_code::failed_to_generate_usr);
290 llvm::Expected<ASTUnit *> ASTUnitOrError =
291 loadExternalAST(LookupName: *LookupName, CrossTUDir, IndexName, DisplayCTUProgress);
292 if (!ASTUnitOrError)
293 return ASTUnitOrError.takeError();
294 ASTUnit *Unit = *ASTUnitOrError;
295 assert(&Unit->getFileManager() ==
296 &Unit->getASTContext().getSourceManager().getFileManager());
297
298 const llvm::Triple &TripleTo = Context.getTargetInfo().getTriple();
299 const llvm::Triple &TripleFrom =
300 Unit->getASTContext().getTargetInfo().getTriple();
301 // The imported AST had been generated for a different target.
302 // Some parts of the triple in the loaded ASTContext can be unknown while the
303 // very same parts in the target ASTContext are known. Thus we check for the
304 // known parts only.
305 if (!hasEqualKnownFields(Lhs: TripleTo, Rhs: TripleFrom)) {
306 // TODO: Pass the SourceLocation of the CallExpression for more precise
307 // diagnostics.
308 ++NumTripleMismatch;
309 return llvm::make_error<IndexError>(Args: index_error_code::triple_mismatch,
310 Args: std::string(Unit->getMainFileName()),
311 Args: TripleTo.str(), Args: TripleFrom.str());
312 }
313
314 const auto &LangTo = Context.getLangOpts();
315 const auto &LangFrom = Unit->getASTContext().getLangOpts();
316
317 // FIXME: Currenty we do not support CTU across C++ and C and across
318 // different dialects of C++.
319 if (LangTo.CPlusPlus != LangFrom.CPlusPlus) {
320 ++NumLangMismatch;
321 return llvm::make_error<IndexError>(Args: index_error_code::lang_mismatch);
322 }
323
324 // If CPP dialects are different then return with error.
325 //
326 // Consider this STL code:
327 // template<typename _Alloc>
328 // struct __alloc_traits
329 // #if __cplusplus >= 201103L
330 // : std::allocator_traits<_Alloc>
331 // #endif
332 // { // ...
333 // };
334 // This class template would create ODR errors during merging the two units,
335 // since in one translation unit the class template has a base class, however
336 // in the other unit it has none.
337 if (LangTo.CPlusPlus11 != LangFrom.CPlusPlus11 ||
338 LangTo.CPlusPlus14 != LangFrom.CPlusPlus14 ||
339 LangTo.CPlusPlus17 != LangFrom.CPlusPlus17 ||
340 LangTo.CPlusPlus20 != LangFrom.CPlusPlus20) {
341 ++NumLangDialectMismatch;
342 return llvm::make_error<IndexError>(
343 Args: index_error_code::lang_dialect_mismatch);
344 }
345
346 TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
347 if (const T *ResultDecl = findDefInDeclContext<T>(TU, *LookupName))
348 return importDefinition(ResultDecl, Unit);
349 return llvm::make_error<IndexError>(Args: index_error_code::failed_import);
350}
351
352llvm::Expected<const FunctionDecl *>
353CrossTranslationUnitContext::getCrossTUDefinition(const FunctionDecl *FD,
354 StringRef CrossTUDir,
355 StringRef IndexName,
356 bool DisplayCTUProgress) {
357 return getCrossTUDefinitionImpl(D: FD, CrossTUDir, IndexName,
358 DisplayCTUProgress);
359}
360
361llvm::Expected<const VarDecl *>
362CrossTranslationUnitContext::getCrossTUDefinition(const VarDecl *VD,
363 StringRef CrossTUDir,
364 StringRef IndexName,
365 bool DisplayCTUProgress) {
366 return getCrossTUDefinitionImpl(D: VD, CrossTUDir, IndexName,
367 DisplayCTUProgress);
368}
369
370void CrossTranslationUnitContext::emitCrossTUDiagnostics(const IndexError &IE) {
371 switch (IE.getCode()) {
372 case index_error_code::missing_index_file:
373 Context.getDiagnostics().Report(DiagID: diag::err_ctu_error_opening)
374 << IE.getFileName();
375 break;
376 case index_error_code::invalid_index_format:
377 Context.getDiagnostics().Report(DiagID: diag::err_extdefmap_parsing)
378 << IE.getFileName() << IE.getLineNum();
379 break;
380 case index_error_code::multiple_definitions:
381 Context.getDiagnostics().Report(DiagID: diag::err_multiple_def_index)
382 << IE.getLineNum();
383 break;
384 case index_error_code::triple_mismatch:
385 Context.getDiagnostics().Report(DiagID: diag::warn_ctu_incompat_triple)
386 << IE.getFileName() << IE.getTripleToName() << IE.getTripleFromName();
387 break;
388 default:
389 break;
390 }
391}
392
393CrossTranslationUnitContext::ASTUnitStorage::ASTUnitStorage(
394 CompilerInstance &CI)
395 : Loader(CI, CI.getAnalyzerOpts().CTUDir,
396 CI.getAnalyzerOpts().CTUInvocationList),
397 LoadGuard(CI.getASTContext().getLangOpts().CPlusPlus
398 ? CI.getAnalyzerOpts().CTUImportCppThreshold
399 : CI.getAnalyzerOpts().CTUImportThreshold) {}
400
401llvm::Expected<ASTUnit *>
402CrossTranslationUnitContext::ASTUnitStorage::getASTUnitForFile(
403 StringRef FileName, bool DisplayCTUProgress) {
404 // Try the cache first.
405 auto ASTCacheEntry = FileASTUnitMap.find(Key: FileName);
406 if (ASTCacheEntry == FileASTUnitMap.end()) {
407
408 // Do not load if the limit is reached.
409 if (!LoadGuard) {
410 ++NumASTLoadThresholdReached;
411 return llvm::make_error<IndexError>(
412 Args: index_error_code::load_threshold_reached);
413 }
414
415 auto LoadAttempt = Loader.load(Identifier: FileName);
416
417 if (!LoadAttempt)
418 return LoadAttempt.takeError();
419
420 std::unique_ptr<ASTUnit> LoadedUnit = std::move(LoadAttempt.get());
421
422 // Need the raw pointer and the unique_ptr as well.
423 ASTUnit *Unit = LoadedUnit.get();
424
425 // Update the cache.
426 FileASTUnitMap[FileName] = std::move(LoadedUnit);
427
428 LoadGuard.indicateLoadSuccess();
429
430 if (DisplayCTUProgress)
431 llvm::errs() << "CTU loaded AST file: " << FileName << "\n";
432
433 return Unit;
434
435 } else {
436 // Found in the cache.
437 return ASTCacheEntry->second.get();
438 }
439}
440
441llvm::Expected<ASTUnit *>
442CrossTranslationUnitContext::ASTUnitStorage::getASTUnitForFunction(
443 StringRef FunctionName, StringRef CrossTUDir, StringRef IndexName,
444 bool DisplayCTUProgress) {
445 // Try the cache first.
446 auto ASTCacheEntry = NameASTUnitMap.find(Key: FunctionName);
447 if (ASTCacheEntry == NameASTUnitMap.end()) {
448 // Load the ASTUnit from the pre-dumped AST file specified by ASTFileName.
449
450 // Ensure that the Index is loaded, as we need to search in it.
451 if (llvm::Error IndexLoadError =
452 ensureCTUIndexLoaded(CrossTUDir, IndexName))
453 return std::move(IndexLoadError);
454
455 // Check if there is an entry in the index for the function.
456 auto It = NameFileMap.find(Key: FunctionName);
457 if (It == NameFileMap.end()) {
458 ++NumNotInOtherTU;
459 return llvm::make_error<IndexError>(Args: index_error_code::missing_definition);
460 }
461
462 // Search in the index for the filename where the definition of FunctionName
463 // resides.
464 if (llvm::Expected<ASTUnit *> FoundForFile =
465 getASTUnitForFile(FileName: It->second, DisplayCTUProgress)) {
466
467 // Update the cache.
468 NameASTUnitMap[FunctionName] = *FoundForFile;
469 return *FoundForFile;
470
471 } else {
472 return FoundForFile.takeError();
473 }
474 } else {
475 // Found in the cache.
476 return ASTCacheEntry->second;
477 }
478}
479
480llvm::Expected<std::string>
481CrossTranslationUnitContext::ASTUnitStorage::getFileForFunction(
482 StringRef FunctionName, StringRef CrossTUDir, StringRef IndexName) {
483 if (llvm::Error IndexLoadError = ensureCTUIndexLoaded(CrossTUDir, IndexName))
484 return std::move(IndexLoadError);
485 return NameFileMap[FunctionName];
486}
487
488llvm::Error CrossTranslationUnitContext::ASTUnitStorage::ensureCTUIndexLoaded(
489 StringRef CrossTUDir, StringRef IndexName) {
490 // Dont initialize if the map is filled.
491 if (!NameFileMap.empty())
492 return llvm::Error::success();
493
494 // Get the absolute path to the index file.
495 SmallString<256> IndexFile = CrossTUDir;
496 if (llvm::sys::path::is_absolute(path: IndexName))
497 IndexFile = IndexName;
498 else
499 llvm::sys::path::append(path&: IndexFile, a: IndexName);
500
501 if (auto IndexMapping = parseCrossTUIndex(IndexPath: IndexFile)) {
502 // Initialize member map.
503 NameFileMap = *IndexMapping;
504 return llvm::Error::success();
505 } else {
506 // Error while parsing CrossTU index file.
507 return IndexMapping.takeError();
508 };
509}
510
511llvm::Expected<ASTUnit *> CrossTranslationUnitContext::loadExternalAST(
512 StringRef LookupName, StringRef CrossTUDir, StringRef IndexName,
513 bool DisplayCTUProgress) {
514 // FIXME: The current implementation only supports loading decls with
515 // a lookup name from a single translation unit. If multiple
516 // translation units contains decls with the same lookup name an
517 // error will be returned.
518
519 // Try to get the value from the heavily cached storage.
520 llvm::Expected<ASTUnit *> Unit = ASTStorage.getASTUnitForFunction(
521 FunctionName: LookupName, CrossTUDir, IndexName, DisplayCTUProgress);
522
523 if (!Unit)
524 return Unit.takeError();
525
526 // Check whether the backing pointer of the Expected is a nullptr.
527 if (!*Unit)
528 return llvm::make_error<IndexError>(
529 Args: index_error_code::failed_to_get_external_ast);
530
531 return Unit;
532}
533
534CrossTranslationUnitContext::ASTLoader::ASTLoader(
535 CompilerInstance &CI, StringRef CTUDir, StringRef InvocationListFilePath)
536 : CI(CI), CTUDir(CTUDir), InvocationListFilePath(InvocationListFilePath) {}
537
538CrossTranslationUnitContext::LoadResultTy
539CrossTranslationUnitContext::ASTLoader::load(StringRef Identifier) {
540 llvm::SmallString<256> Path;
541 if (llvm::sys::path::is_absolute(path: Identifier, style: PathStyle)) {
542 Path = Identifier;
543 } else {
544 Path = CTUDir;
545 llvm::sys::path::append(path&: Path, style: PathStyle, a: Identifier);
546 }
547
548 // The path is stored in the InvocationList member in posix style. To
549 // successfully lookup an entry based on filepath, it must be converted.
550 llvm::sys::path::native(path&: Path, style: PathStyle);
551
552 // Normalize by removing relative path components.
553 llvm::sys::path::remove_dots(path&: Path, /*remove_dot_dot*/ true, style: PathStyle);
554
555 if (Path.ends_with(Suffix: ".ast"))
556 return loadFromDump(Identifier: Path);
557 else
558 return loadFromSource(Identifier: Path);
559}
560
561CrossTranslationUnitContext::LoadResultTy
562CrossTranslationUnitContext::ASTLoader::loadFromDump(StringRef ASTDumpPath) {
563 auto DiagOpts = std::make_shared<DiagnosticOptions>();
564 TextDiagnosticPrinter *DiagClient =
565 new TextDiagnosticPrinter(llvm::errs(), *DiagOpts);
566 IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
567 IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
568 new DiagnosticsEngine(DiagID, *DiagOpts, DiagClient));
569 return ASTUnit::LoadFromASTFile(
570 Filename: ASTDumpPath, PCHContainerRdr: CI.getPCHContainerOperations()->getRawReader(),
571 ToLoad: ASTUnit::LoadEverything, DiagOpts, Diags, FileSystemOpts: CI.getFileSystemOpts(),
572 HSOpts: CI.getHeaderSearchOpts());
573}
574
575/// Load the AST from a source-file, which is supposed to be located inside the
576/// YAML formatted invocation list file under the filesystem path specified by
577/// \p InvocationList. The invocation list should contain absolute paths.
578/// \p SourceFilePath is the absolute path of the source file that contains the
579/// function definition the analysis is looking for. The Index is built by the
580/// \p clang-extdef-mapping tool, which is also supposed to be generating
581/// absolute paths.
582///
583/// Proper diagnostic emission requires absolute paths, so even if a future
584/// change introduces the handling of relative paths, this must be taken into
585/// consideration.
586CrossTranslationUnitContext::LoadResultTy
587CrossTranslationUnitContext::ASTLoader::loadFromSource(
588 StringRef SourceFilePath) {
589
590 if (llvm::Error InitError = lazyInitInvocationList())
591 return std::move(InitError);
592 assert(InvocationList);
593
594 auto Invocation = InvocationList->find(Key: SourceFilePath);
595 if (Invocation == InvocationList->end())
596 return llvm::make_error<IndexError>(
597 Args: index_error_code::invocation_list_lookup_unsuccessful);
598
599 const InvocationListTy::mapped_type &InvocationCommand = Invocation->second;
600
601 SmallVector<const char *, 32> CommandLineArgs(InvocationCommand.size());
602 std::transform(first: InvocationCommand.begin(), last: InvocationCommand.end(),
603 result: CommandLineArgs.begin(),
604 unary_op: [](auto &&CmdPart) { return CmdPart.c_str(); });
605
606 auto DiagOpts = std::make_shared<DiagnosticOptions>(args&: CI.getDiagnosticOpts());
607 auto *DiagClient = new ForwardingDiagnosticConsumer{CI.getDiagnosticClient()};
608 IntrusiveRefCntPtr<DiagnosticIDs> DiagID{
609 CI.getDiagnostics().getDiagnosticIDs()};
610 IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
611 new DiagnosticsEngine{DiagID, *DiagOpts, DiagClient});
612
613 return ASTUnit::LoadFromCommandLine(
614 ArgBegin: CommandLineArgs.begin(), ArgEnd: (CommandLineArgs.end()),
615 PCHContainerOps: CI.getPCHContainerOperations(), DiagOpts, Diags,
616 ResourceFilesPath: CI.getHeaderSearchOpts().ResourceDir);
617}
618
619llvm::Expected<InvocationListTy>
620parseInvocationList(StringRef FileContent, llvm::sys::path::Style PathStyle) {
621 InvocationListTy InvocationList;
622
623 /// LLVM YAML parser is used to extract information from invocation list file.
624 llvm::SourceMgr SM;
625 llvm::yaml::Stream InvocationFile(FileContent, SM);
626
627 /// Only the first document is processed.
628 llvm::yaml::document_iterator FirstInvocationFile = InvocationFile.begin();
629
630 /// There has to be at least one document available.
631 if (FirstInvocationFile == InvocationFile.end())
632 return llvm::make_error<IndexError>(
633 Args: index_error_code::invocation_list_empty);
634
635 llvm::yaml::Node *DocumentRoot = FirstInvocationFile->getRoot();
636 if (!DocumentRoot)
637 return llvm::make_error<IndexError>(
638 Args: index_error_code::invocation_list_wrong_format);
639
640 /// According to the format specified the document must be a mapping, where
641 /// the keys are paths to source files, and values are sequences of invocation
642 /// parts.
643 auto *Mappings = dyn_cast<llvm::yaml::MappingNode>(Val: DocumentRoot);
644 if (!Mappings)
645 return llvm::make_error<IndexError>(
646 Args: index_error_code::invocation_list_wrong_format);
647
648 for (auto &NextMapping : *Mappings) {
649 /// The keys should be strings, which represent a source-file path.
650 auto *Key = dyn_cast<llvm::yaml::ScalarNode>(Val: NextMapping.getKey());
651 if (!Key)
652 return llvm::make_error<IndexError>(
653 Args: index_error_code::invocation_list_wrong_format);
654
655 SmallString<32> ValueStorage;
656 StringRef SourcePath = Key->getValue(Storage&: ValueStorage);
657
658 // Store paths with PathStyle directory separator.
659 SmallString<32> NativeSourcePath(SourcePath);
660 llvm::sys::path::native(path&: NativeSourcePath, style: PathStyle);
661
662 StringRef InvocationKey = NativeSourcePath;
663
664 if (InvocationList.contains(Key: InvocationKey))
665 return llvm::make_error<IndexError>(
666 Args: index_error_code::invocation_list_ambiguous);
667
668 /// The values should be sequences of strings, each representing a part of
669 /// the invocation.
670 auto *Args = dyn_cast<llvm::yaml::SequenceNode>(Val: NextMapping.getValue());
671 if (!Args)
672 return llvm::make_error<IndexError>(
673 Args: index_error_code::invocation_list_wrong_format);
674
675 for (auto &Arg : *Args) {
676 auto *CmdString = dyn_cast<llvm::yaml::ScalarNode>(Val: &Arg);
677 if (!CmdString)
678 return llvm::make_error<IndexError>(
679 Args: index_error_code::invocation_list_wrong_format);
680 /// Every conversion starts with an empty working storage, as it is not
681 /// clear if this is a requirement of the YAML parser.
682 ValueStorage.clear();
683 InvocationList[InvocationKey].emplace_back(
684 Args: CmdString->getValue(Storage&: ValueStorage));
685 }
686
687 if (InvocationList[InvocationKey].empty())
688 return llvm::make_error<IndexError>(
689 Args: index_error_code::invocation_list_wrong_format);
690 }
691
692 return InvocationList;
693}
694
695llvm::Error CrossTranslationUnitContext::ASTLoader::lazyInitInvocationList() {
696 /// Lazily initialize the invocation list member used for on-demand parsing.
697 if (InvocationList)
698 return llvm::Error::success();
699 if (index_error_code::success != PreviousParsingResult)
700 return llvm::make_error<IndexError>(Args&: PreviousParsingResult);
701
702 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> FileContent =
703 llvm::MemoryBuffer::getFile(Filename: InvocationListFilePath);
704 if (!FileContent) {
705 PreviousParsingResult = index_error_code::invocation_list_file_not_found;
706 return llvm::make_error<IndexError>(Args&: PreviousParsingResult);
707 }
708 std::unique_ptr<llvm::MemoryBuffer> ContentBuffer = std::move(*FileContent);
709 assert(ContentBuffer && "If no error was produced after loading, the pointer "
710 "should not be nullptr.");
711
712 llvm::Expected<InvocationListTy> ExpectedInvocationList =
713 parseInvocationList(FileContent: ContentBuffer->getBuffer(), PathStyle);
714
715 // Handle the error to store the code for next call to this function.
716 if (!ExpectedInvocationList) {
717 llvm::handleAllErrors(
718 E: ExpectedInvocationList.takeError(),
719 Handlers: [&](const IndexError &E) { PreviousParsingResult = E.getCode(); });
720 return llvm::make_error<IndexError>(Args&: PreviousParsingResult);
721 }
722
723 InvocationList = *ExpectedInvocationList;
724
725 return llvm::Error::success();
726}
727
728template <typename T>
729llvm::Expected<const T *>
730CrossTranslationUnitContext::importDefinitionImpl(const T *D, ASTUnit *Unit) {
731 assert(hasBodyOrInit(D) && "Decls to be imported should have body or init.");
732
733 assert(&D->getASTContext() == &Unit->getASTContext() &&
734 "ASTContext of Decl and the unit should match.");
735 ASTImporter &Importer = getOrCreateASTImporter(Unit);
736
737 auto ToDeclOrError = Importer.Import(D);
738 if (!ToDeclOrError) {
739 handleAllErrors(ToDeclOrError.takeError(), [&](const ASTImportError &IE) {
740 switch (IE.Error) {
741 case ASTImportError::NameConflict:
742 ++NumNameConflicts;
743 break;
744 case ASTImportError::UnsupportedConstruct:
745 ++NumUnsupportedNodeFound;
746 break;
747 case ASTImportError::Unknown:
748 llvm_unreachable("Unknown import error happened.");
749 break;
750 }
751 });
752 return llvm::make_error<IndexError>(Args: index_error_code::failed_import);
753 }
754 auto *ToDecl = cast<T>(*ToDeclOrError);
755 assert(hasBodyOrInit(ToDecl) && "Imported Decl should have body or init.");
756 ++NumGetCTUSuccess;
757
758 // Parent map is invalidated after changing the AST.
759 ToDecl->getASTContext().getParentMapContext().clear();
760
761 return ToDecl;
762}
763
764llvm::Expected<const FunctionDecl *>
765CrossTranslationUnitContext::importDefinition(const FunctionDecl *FD,
766 ASTUnit *Unit) {
767 return importDefinitionImpl(D: FD, Unit);
768}
769
770llvm::Expected<const VarDecl *>
771CrossTranslationUnitContext::importDefinition(const VarDecl *VD,
772 ASTUnit *Unit) {
773 return importDefinitionImpl(D: VD, Unit);
774}
775
776void CrossTranslationUnitContext::lazyInitImporterSharedSt(
777 TranslationUnitDecl *ToTU) {
778 if (!ImporterSharedSt)
779 ImporterSharedSt = std::make_shared<ASTImporterSharedState>(args&: *ToTU);
780}
781
782ASTImporter &
783CrossTranslationUnitContext::getOrCreateASTImporter(ASTUnit *Unit) {
784 ASTContext &From = Unit->getASTContext();
785
786 auto I = ASTUnitImporterMap.find(Val: From.getTranslationUnitDecl());
787 if (I != ASTUnitImporterMap.end())
788 return *I->second;
789 lazyInitImporterSharedSt(ToTU: Context.getTranslationUnitDecl());
790 ASTImporter *NewImporter = new ASTImporter(
791 Context, Context.getSourceManager().getFileManager(), From,
792 From.getSourceManager().getFileManager(), false, ImporterSharedSt);
793 ASTUnitImporterMap[From.getTranslationUnitDecl()].reset(p: NewImporter);
794 return *NewImporter;
795}
796
797std::optional<clang::MacroExpansionContext>
798CrossTranslationUnitContext::getMacroExpansionContextForSourceLocation(
799 const clang::SourceLocation &ToLoc) const {
800 // FIXME: Implement: Record such a context for every imported ASTUnit; lookup.
801 return std::nullopt;
802}
803
804bool CrossTranslationUnitContext::isImportedAsNew(const Decl *ToDecl) const {
805 if (!ImporterSharedSt)
806 return false;
807 return ImporterSharedSt->isNewDecl(ToD: const_cast<Decl *>(ToDecl));
808}
809
810bool CrossTranslationUnitContext::hasError(const Decl *ToDecl) const {
811 if (!ImporterSharedSt)
812 return false;
813 return static_cast<bool>(
814 ImporterSharedSt->getImportDeclErrorIfAny(ToD: const_cast<Decl *>(ToDecl)));
815}
816
817} // namespace cross_tu
818} // namespace clang
819