Bug Summary

File:clang/lib/Serialization/ModuleManager.cpp
Warning:line 153, column 12
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ModuleManager.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/tools/clang/lib/Serialization -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/lib/Serialization -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/include -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/include -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/tools/clang/lib/Serialization -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2020-11-21-121427-42170-1 -x c++ /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/lib/Serialization/ModuleManager.cpp
1//===- ModuleManager.cpp - Module Manager ---------------------------------===//
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 defines the ModuleManager class, which manages a set of loaded
10// modules for the ASTReader.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Serialization/ModuleManager.h"
15#include "clang/Basic/FileManager.h"
16#include "clang/Basic/LLVM.h"
17#include "clang/Lex/HeaderSearch.h"
18#include "clang/Lex/ModuleMap.h"
19#include "clang/Serialization/GlobalModuleIndex.h"
20#include "clang/Serialization/InMemoryModuleCache.h"
21#include "clang/Serialization/ModuleFile.h"
22#include "clang/Serialization/PCHContainerOperations.h"
23#include "llvm/ADT/STLExtras.h"
24#include "llvm/ADT/SetVector.h"
25#include "llvm/ADT/SmallPtrSet.h"
26#include "llvm/ADT/SmallVector.h"
27#include "llvm/ADT/StringRef.h"
28#include "llvm/ADT/iterator.h"
29#include "llvm/Support/Chrono.h"
30#include "llvm/Support/DOTGraphTraits.h"
31#include "llvm/Support/ErrorOr.h"
32#include "llvm/Support/GraphWriter.h"
33#include "llvm/Support/MemoryBuffer.h"
34#include "llvm/Support/VirtualFileSystem.h"
35#include <algorithm>
36#include <cassert>
37#include <memory>
38#include <string>
39#include <system_error>
40
41using namespace clang;
42using namespace serialization;
43
44ModuleFile *ModuleManager::lookupByFileName(StringRef Name) const {
45 auto Entry = FileMgr.getFile(Name, /*OpenFile=*/false,
46 /*CacheFailure=*/false);
47 if (Entry)
48 return lookup(*Entry);
49
50 return nullptr;
51}
52
53ModuleFile *ModuleManager::lookupByModuleName(StringRef Name) const {
54 if (const Module *Mod = HeaderSearchInfo.getModuleMap().findModule(Name))
55 if (const FileEntry *File = Mod->getASTFile())
56 return lookup(File);
57
58 return nullptr;
59}
60
61ModuleFile *ModuleManager::lookup(const FileEntry *File) const {
62 auto Known = Modules.find(File);
63 if (Known == Modules.end())
64 return nullptr;
65
66 return Known->second;
67}
68
69std::unique_ptr<llvm::MemoryBuffer>
70ModuleManager::lookupBuffer(StringRef Name) {
71 auto Entry = FileMgr.getFile(Name, /*OpenFile=*/false,
72 /*CacheFailure=*/false);
73 if (!Entry)
74 return nullptr;
75 return std::move(InMemoryBuffers[*Entry]);
76}
77
78static bool checkSignature(ASTFileSignature Signature,
79 ASTFileSignature ExpectedSignature,
80 std::string &ErrorStr) {
81 if (!ExpectedSignature || Signature == ExpectedSignature)
82 return false;
83
84 ErrorStr =
85 Signature ? "signature mismatch" : "could not read module signature";
86 return true;
87}
88
89static void updateModuleImports(ModuleFile &MF, ModuleFile *ImportedBy,
90 SourceLocation ImportLoc) {
91 if (ImportedBy) {
92 MF.ImportedBy.insert(ImportedBy);
93 ImportedBy->Imports.insert(&MF);
94 } else {
95 if (!MF.DirectlyImported)
96 MF.ImportLoc = ImportLoc;
97
98 MF.DirectlyImported = true;
99 }
100}
101
102ModuleManager::AddModuleResult
103ModuleManager::addModule(StringRef FileName, ModuleKind Type,
104 SourceLocation ImportLoc, ModuleFile *ImportedBy,
105 unsigned Generation,
106 off_t ExpectedSize, time_t ExpectedModTime,
107 ASTFileSignature ExpectedSignature,
108 ASTFileSignatureReader ReadSignature,
109 ModuleFile *&Module,
110 std::string &ErrorStr) {
111 Module = nullptr;
112
113 // Look for the file entry. This only fails if the expected size or
114 // modification time differ.
115 const FileEntry *Entry;
116 if (Type == MK_ExplicitModule || Type == MK_PrebuiltModule) {
1
Assuming 'Type' is not equal to MK_ExplicitModule
2
Assuming 'Type' is not equal to MK_PrebuiltModule
3
Taking false branch
117 // If we're not expecting to pull this file out of the module cache, it
118 // might have a different mtime due to being moved across filesystems in
119 // a distributed build. The size must still match, though. (As must the
120 // contents, but we can't check that.)
121 ExpectedModTime = 0;
122 }
123 // Note: ExpectedSize and ExpectedModTime will be 0 for MK_ImplicitModule
124 // when using an ASTFileSignature.
125 if (lookupModuleFile(FileName, ExpectedSize, ExpectedModTime, Entry)) {
4
Calling 'ModuleManager::lookupModuleFile'
9
Returning from 'ModuleManager::lookupModuleFile'
10
Taking false branch
126 ErrorStr = "module file out of date";
127 return OutOfDate;
128 }
129
130 if (!Entry
10.1
'Entry' is null
&& FileName != "-") {
11
Taking false branch
131 ErrorStr = "module file not found";
132 return Missing;
133 }
134
135 // The ModuleManager's use of FileEntry nodes as the keys for its map of
136 // loaded modules is less than ideal. Uniqueness for FileEntry nodes is
137 // maintained by FileManager, which in turn uses inode numbers on hosts
138 // that support that. When coupled with the module cache's proclivity for
139 // turning over and deleting stale PCMs, this means entries for different
140 // module files can wind up reusing the same underlying inode. When this
141 // happens, subsequent accesses to the Modules map will disagree on the
142 // ModuleFile associated with a given file. In general, it is not sufficient
143 // to resolve this conundrum with a type like FileEntryRef that stores the
144 // name of the FileEntry node on first access because of path canonicalization
145 // issues. However, the paths constructed for implicit module builds are
146 // fully under Clang's control. We *can*, therefore, rely on their structure
147 // being consistent across operating systems and across subsequent accesses
148 // to the Modules map.
149 auto implicitModuleNamesMatch = [](ModuleKind Kind, const ModuleFile *MF,
150 const FileEntry *Entry) -> bool {
151 if (Kind != MK_ImplicitModule)
16
Assuming 'Kind' is equal to MK_ImplicitModule
17
Taking false branch
152 return true;
153 return Entry->getName() == MF->FileName;
18
Called C++ object pointer is null
154 };
155
156 // Check whether we already loaded this module, before
157 if (ModuleFile *ModuleEntry = Modules.lookup(Entry)) {
12
Assuming 'ModuleEntry' is non-null
13
Taking true branch
158 if (implicitModuleNamesMatch(Type, ModuleEntry, Entry)) {
14
Passing null pointer value via 3rd parameter 'Entry'
15
Calling 'operator()'
159 // Check the stored signature.
160 if (checkSignature(ModuleEntry->Signature, ExpectedSignature, ErrorStr))
161 return OutOfDate;
162
163 Module = ModuleEntry;
164 updateModuleImports(*ModuleEntry, ImportedBy, ImportLoc);
165 return AlreadyLoaded;
166 }
167 }
168
169 // Allocate a new module.
170 auto NewModule = std::make_unique<ModuleFile>(Type, Generation);
171 NewModule->Index = Chain.size();
172 NewModule->FileName = FileName.str();
173 NewModule->File = Entry;
174 NewModule->ImportLoc = ImportLoc;
175 NewModule->InputFilesValidationTimestamp = 0;
176
177 if (NewModule->Kind == MK_ImplicitModule) {
178 std::string TimestampFilename = NewModule->getTimestampFilename();
179 llvm::vfs::Status Status;
180 // A cached stat value would be fine as well.
181 if (!FileMgr.getNoncachedStatValue(TimestampFilename, Status))
182 NewModule->InputFilesValidationTimestamp =
183 llvm::sys::toTimeT(Status.getLastModificationTime());
184 }
185
186 // Load the contents of the module
187 if (std::unique_ptr<llvm::MemoryBuffer> Buffer = lookupBuffer(FileName)) {
188 // The buffer was already provided for us.
189 NewModule->Buffer = &ModuleCache->addBuiltPCM(FileName, std::move(Buffer));
190 // Since the cached buffer is reused, it is safe to close the file
191 // descriptor that was opened while stat()ing the PCM in
192 // lookupModuleFile() above, it won't be needed any longer.
193 Entry->closeFile();
194 } else if (llvm::MemoryBuffer *Buffer =
195 getModuleCache().lookupPCM(FileName)) {
196 NewModule->Buffer = Buffer;
197 // As above, the file descriptor is no longer needed.
198 Entry->closeFile();
199 } else if (getModuleCache().shouldBuildPCM(FileName)) {
200 // Report that the module is out of date, since we tried (and failed) to
201 // import it earlier.
202 Entry->closeFile();
203 return OutOfDate;
204 } else {
205 // Open the AST file.
206 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Buf((std::error_code()));
207 if (FileName == "-") {
208 Buf = llvm::MemoryBuffer::getSTDIN();
209 } else {
210 // Get a buffer of the file and close the file descriptor when done.
211 // The file is volatile because in a parallel build we expect multiple
212 // compiler processes to use the same module file rebuilding it if needed.
213 //
214 // RequiresNullTerminator is false because module files don't need it, and
215 // this allows the file to still be mmapped.
216 Buf = FileMgr.getBufferForFile(NewModule->File,
217 /*IsVolatile=*/true,
218 /*RequiresNullTerminator=*/false);
219 }
220
221 if (!Buf) {
222 ErrorStr = Buf.getError().message();
223 return Missing;
224 }
225
226 NewModule->Buffer = &getModuleCache().addPCM(FileName, std::move(*Buf));
227 }
228
229 // Initialize the stream.
230 NewModule->Data = PCHContainerRdr.ExtractPCH(*NewModule->Buffer);
231
232 // Read the signature eagerly now so that we can check it. Avoid calling
233 // ReadSignature unless there's something to check though.
234 if (ExpectedSignature && checkSignature(ReadSignature(NewModule->Data),
235 ExpectedSignature, ErrorStr))
236 return OutOfDate;
237
238 // We're keeping this module. Store it everywhere.
239 Module = Modules[Entry] = NewModule.get();
240
241 updateModuleImports(*NewModule, ImportedBy, ImportLoc);
242
243 if (!NewModule->isModule())
244 PCHChain.push_back(NewModule.get());
245 if (!ImportedBy)
246 Roots.push_back(NewModule.get());
247
248 Chain.push_back(std::move(NewModule));
249 return NewlyLoaded;
250}
251
252void ModuleManager::removeModules(ModuleIterator First, ModuleMap *modMap) {
253 auto Last = end();
254 if (First == Last)
255 return;
256
257 // Explicitly clear VisitOrder since we might not notice it is stale.
258 VisitOrder.clear();
259
260 // Collect the set of module file pointers that we'll be removing.
261 llvm::SmallPtrSet<ModuleFile *, 4> victimSet(
262 (llvm::pointer_iterator<ModuleIterator>(First)),
263 (llvm::pointer_iterator<ModuleIterator>(Last)));
264
265 auto IsVictim = [&](ModuleFile *MF) {
266 return victimSet.count(MF);
267 };
268 // Remove any references to the now-destroyed modules.
269 for (auto I = begin(); I != First; ++I) {
270 I->Imports.remove_if(IsVictim);
271 I->ImportedBy.remove_if(IsVictim);
272 }
273 Roots.erase(std::remove_if(Roots.begin(), Roots.end(), IsVictim),
274 Roots.end());
275
276 // Remove the modules from the PCH chain.
277 for (auto I = First; I != Last; ++I) {
278 if (!I->isModule()) {
279 PCHChain.erase(llvm::find(PCHChain, &*I), PCHChain.end());
280 break;
281 }
282 }
283
284 // Delete the modules and erase them from the various structures.
285 for (ModuleIterator victim = First; victim != Last; ++victim) {
286 Modules.erase(victim->File);
287
288 if (modMap) {
289 StringRef ModuleName = victim->ModuleName;
290 if (Module *mod = modMap->findModule(ModuleName)) {
291 mod->setASTFile(nullptr);
292 }
293 }
294 }
295
296 // Delete the modules.
297 Chain.erase(Chain.begin() + (First - begin()), Chain.end());
298}
299
300void
301ModuleManager::addInMemoryBuffer(StringRef FileName,
302 std::unique_ptr<llvm::MemoryBuffer> Buffer) {
303 const FileEntry *Entry =
304 FileMgr.getVirtualFile(FileName, Buffer->getBufferSize(), 0);
305 InMemoryBuffers[Entry] = std::move(Buffer);
306}
307
308ModuleManager::VisitState *ModuleManager::allocateVisitState() {
309 // Fast path: if we have a cached state, use it.
310 if (FirstVisitState) {
311 VisitState *Result = FirstVisitState;
312 FirstVisitState = FirstVisitState->NextState;
313 Result->NextState = nullptr;
314 return Result;
315 }
316
317 // Allocate and return a new state.
318 return new VisitState(size());
319}
320
321void ModuleManager::returnVisitState(VisitState *State) {
322 assert(State->NextState == nullptr && "Visited state is in list?")((State->NextState == nullptr && "Visited state is in list?"
) ? static_cast<void> (0) : __assert_fail ("State->NextState == nullptr && \"Visited state is in list?\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/lib/Serialization/ModuleManager.cpp"
, 322, __PRETTY_FUNCTION__))
;
323 State->NextState = FirstVisitState;
324 FirstVisitState = State;
325}
326
327void ModuleManager::setGlobalIndex(GlobalModuleIndex *Index) {
328 GlobalIndex = Index;
329 if (!GlobalIndex) {
330 ModulesInCommonWithGlobalIndex.clear();
331 return;
332 }
333
334 // Notify the global module index about all of the modules we've already
335 // loaded.
336 for (ModuleFile &M : *this)
337 if (!GlobalIndex->loadedModuleFile(&M))
338 ModulesInCommonWithGlobalIndex.push_back(&M);
339}
340
341void ModuleManager::moduleFileAccepted(ModuleFile *MF) {
342 if (!GlobalIndex || GlobalIndex->loadedModuleFile(MF))
343 return;
344
345 ModulesInCommonWithGlobalIndex.push_back(MF);
346}
347
348ModuleManager::ModuleManager(FileManager &FileMgr,
349 InMemoryModuleCache &ModuleCache,
350 const PCHContainerReader &PCHContainerRdr,
351 const HeaderSearch &HeaderSearchInfo)
352 : FileMgr(FileMgr), ModuleCache(&ModuleCache),
353 PCHContainerRdr(PCHContainerRdr), HeaderSearchInfo(HeaderSearchInfo) {}
354
355ModuleManager::~ModuleManager() { delete FirstVisitState; }
356
357void ModuleManager::visit(llvm::function_ref<bool(ModuleFile &M)> Visitor,
358 llvm::SmallPtrSetImpl<ModuleFile *> *ModuleFilesHit) {
359 // If the visitation order vector is the wrong size, recompute the order.
360 if (VisitOrder.size() != Chain.size()) {
361 unsigned N = size();
362 VisitOrder.clear();
363 VisitOrder.reserve(N);
364
365 // Record the number of incoming edges for each module. When we
366 // encounter a module with no incoming edges, push it into the queue
367 // to seed the queue.
368 SmallVector<ModuleFile *, 4> Queue;
369 Queue.reserve(N);
370 llvm::SmallVector<unsigned, 4> UnusedIncomingEdges;
371 UnusedIncomingEdges.resize(size());
372 for (ModuleFile &M : llvm::reverse(*this)) {
373 unsigned Size = M.ImportedBy.size();
374 UnusedIncomingEdges[M.Index] = Size;
375 if (!Size)
376 Queue.push_back(&M);
377 }
378
379 // Traverse the graph, making sure to visit a module before visiting any
380 // of its dependencies.
381 while (!Queue.empty()) {
382 ModuleFile *CurrentModule = Queue.pop_back_val();
383 VisitOrder.push_back(CurrentModule);
384
385 // For any module that this module depends on, push it on the
386 // stack (if it hasn't already been marked as visited).
387 for (auto M = CurrentModule->Imports.rbegin(),
388 MEnd = CurrentModule->Imports.rend();
389 M != MEnd; ++M) {
390 // Remove our current module as an impediment to visiting the
391 // module we depend on. If we were the last unvisited module
392 // that depends on this particular module, push it into the
393 // queue to be visited.
394 unsigned &NumUnusedEdges = UnusedIncomingEdges[(*M)->Index];
395 if (NumUnusedEdges && (--NumUnusedEdges == 0))
396 Queue.push_back(*M);
397 }
398 }
399
400 assert(VisitOrder.size() == N && "Visitation order is wrong?")((VisitOrder.size() == N && "Visitation order is wrong?"
) ? static_cast<void> (0) : __assert_fail ("VisitOrder.size() == N && \"Visitation order is wrong?\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/lib/Serialization/ModuleManager.cpp"
, 400, __PRETTY_FUNCTION__))
;
401
402 delete FirstVisitState;
403 FirstVisitState = nullptr;
404 }
405
406 VisitState *State = allocateVisitState();
407 unsigned VisitNumber = State->NextVisitNumber++;
408
409 // If the caller has provided us with a hit-set that came from the global
410 // module index, mark every module file in common with the global module
411 // index that is *not* in that set as 'visited'.
412 if (ModuleFilesHit && !ModulesInCommonWithGlobalIndex.empty()) {
413 for (unsigned I = 0, N = ModulesInCommonWithGlobalIndex.size(); I != N; ++I)
414 {
415 ModuleFile *M = ModulesInCommonWithGlobalIndex[I];
416 if (!ModuleFilesHit->count(M))
417 State->VisitNumber[M->Index] = VisitNumber;
418 }
419 }
420
421 for (unsigned I = 0, N = VisitOrder.size(); I != N; ++I) {
422 ModuleFile *CurrentModule = VisitOrder[I];
423 // Should we skip this module file?
424 if (State->VisitNumber[CurrentModule->Index] == VisitNumber)
425 continue;
426
427 // Visit the module.
428 assert(State->VisitNumber[CurrentModule->Index] == VisitNumber - 1)((State->VisitNumber[CurrentModule->Index] == VisitNumber
- 1) ? static_cast<void> (0) : __assert_fail ("State->VisitNumber[CurrentModule->Index] == VisitNumber - 1"
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/clang/lib/Serialization/ModuleManager.cpp"
, 428, __PRETTY_FUNCTION__))
;
429 State->VisitNumber[CurrentModule->Index] = VisitNumber;
430 if (!Visitor(*CurrentModule))
431 continue;
432
433 // The visitor has requested that cut off visitation of any
434 // module that the current module depends on. To indicate this
435 // behavior, we mark all of the reachable modules as having been visited.
436 ModuleFile *NextModule = CurrentModule;
437 do {
438 // For any module that this module depends on, push it on the
439 // stack (if it hasn't already been marked as visited).
440 for (llvm::SetVector<ModuleFile *>::iterator
441 M = NextModule->Imports.begin(),
442 MEnd = NextModule->Imports.end();
443 M != MEnd; ++M) {
444 if (State->VisitNumber[(*M)->Index] != VisitNumber) {
445 State->Stack.push_back(*M);
446 State->VisitNumber[(*M)->Index] = VisitNumber;
447 }
448 }
449
450 if (State->Stack.empty())
451 break;
452
453 // Pop the next module off the stack.
454 NextModule = State->Stack.pop_back_val();
455 } while (true);
456 }
457
458 returnVisitState(State);
459}
460
461bool ModuleManager::lookupModuleFile(StringRef FileName,
462 off_t ExpectedSize,
463 time_t ExpectedModTime,
464 const FileEntry *&File) {
465 File = nullptr;
5
Null pointer value stored to 'Entry'
466 if (FileName == "-")
6
Assuming the condition is true
7
Taking true branch
467 return false;
8
Returning zero, which participates in a condition later
468
469 // Open the file immediately to ensure there is no race between stat'ing and
470 // opening the file.
471 auto FileOrErr = FileMgr.getFile(FileName, /*OpenFile=*/true,
472 /*CacheFailure=*/false);
473 if (!FileOrErr)
474 return false;
475
476 File = *FileOrErr;
477
478 if ((ExpectedSize && ExpectedSize != File->getSize()) ||
479 (ExpectedModTime && ExpectedModTime != File->getModificationTime()))
480 // Do not destroy File, as it may be referenced. If we need to rebuild it,
481 // it will be destroyed by removeModules.
482 return true;
483
484 return false;
485}
486
487#ifndef NDEBUG
488namespace llvm {
489
490 template<>
491 struct GraphTraits<ModuleManager> {
492 using NodeRef = ModuleFile *;
493 using ChildIteratorType = llvm::SetVector<ModuleFile *>::const_iterator;
494 using nodes_iterator = pointer_iterator<ModuleManager::ModuleConstIterator>;
495
496 static ChildIteratorType child_begin(NodeRef Node) {
497 return Node->Imports.begin();
498 }
499
500 static ChildIteratorType child_end(NodeRef Node) {
501 return Node->Imports.end();
502 }
503
504 static nodes_iterator nodes_begin(const ModuleManager &Manager) {
505 return nodes_iterator(Manager.begin());
506 }
507
508 static nodes_iterator nodes_end(const ModuleManager &Manager) {
509 return nodes_iterator(Manager.end());
510 }
511 };
512
513 template<>
514 struct DOTGraphTraits<ModuleManager> : public DefaultDOTGraphTraits {
515 explicit DOTGraphTraits(bool IsSimple = false)
516 : DefaultDOTGraphTraits(IsSimple) {}
517
518 static bool renderGraphFromBottomUp() { return true; }
519
520 std::string getNodeLabel(ModuleFile *M, const ModuleManager&) {
521 return M->ModuleName;
522 }
523 };
524
525} // namespace llvm
526
527void ModuleManager::viewGraph() {
528 llvm::ViewGraph(*this, "Modules");
529}
530#endif