File: | llvm/include/llvm/Bitstream/BitstreamReader.h |
Warning: | line 220, column 39 The result of the right shift is undefined due to shifting by '64', which is greater or equal to the width of type 'llvm::SimpleBitstreamCursor::word_t' |
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1 | //===--- GlobalModuleIndex.cpp - Global Module Index ------------*- 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 GlobalModuleIndex class. | |||
10 | // | |||
11 | //===----------------------------------------------------------------------===// | |||
12 | ||||
13 | #include "ASTReaderInternals.h" | |||
14 | #include "clang/Basic/FileManager.h" | |||
15 | #include "clang/Lex/HeaderSearch.h" | |||
16 | #include "clang/Serialization/ASTBitCodes.h" | |||
17 | #include "clang/Serialization/GlobalModuleIndex.h" | |||
18 | #include "clang/Serialization/Module.h" | |||
19 | #include "clang/Serialization/PCHContainerOperations.h" | |||
20 | #include "llvm/ADT/DenseMap.h" | |||
21 | #include "llvm/ADT/MapVector.h" | |||
22 | #include "llvm/ADT/SmallString.h" | |||
23 | #include "llvm/ADT/StringRef.h" | |||
24 | #include "llvm/Bitstream/BitstreamReader.h" | |||
25 | #include "llvm/Bitstream/BitstreamWriter.h" | |||
26 | #include "llvm/Support/DJB.h" | |||
27 | #include "llvm/Support/FileSystem.h" | |||
28 | #include "llvm/Support/FileUtilities.h" | |||
29 | #include "llvm/Support/LockFileManager.h" | |||
30 | #include "llvm/Support/MemoryBuffer.h" | |||
31 | #include "llvm/Support/OnDiskHashTable.h" | |||
32 | #include "llvm/Support/Path.h" | |||
33 | #include "llvm/Support/TimeProfiler.h" | |||
34 | #include <cstdio> | |||
35 | using namespace clang; | |||
36 | using namespace serialization; | |||
37 | ||||
38 | //----------------------------------------------------------------------------// | |||
39 | // Shared constants | |||
40 | //----------------------------------------------------------------------------// | |||
41 | namespace { | |||
42 | enum { | |||
43 | /// The block containing the index. | |||
44 | GLOBAL_INDEX_BLOCK_ID = llvm::bitc::FIRST_APPLICATION_BLOCKID | |||
45 | }; | |||
46 | ||||
47 | /// Describes the record types in the index. | |||
48 | enum IndexRecordTypes { | |||
49 | /// Contains version information and potentially other metadata, | |||
50 | /// used to determine if we can read this global index file. | |||
51 | INDEX_METADATA, | |||
52 | /// Describes a module, including its file name and dependencies. | |||
53 | MODULE, | |||
54 | /// The index for identifiers. | |||
55 | IDENTIFIER_INDEX | |||
56 | }; | |||
57 | } | |||
58 | ||||
59 | /// The name of the global index file. | |||
60 | static const char * const IndexFileName = "modules.idx"; | |||
61 | ||||
62 | /// The global index file version. | |||
63 | static const unsigned CurrentVersion = 1; | |||
64 | ||||
65 | //----------------------------------------------------------------------------// | |||
66 | // Global module index reader. | |||
67 | //----------------------------------------------------------------------------// | |||
68 | ||||
69 | namespace { | |||
70 | ||||
71 | /// Trait used to read the identifier index from the on-disk hash | |||
72 | /// table. | |||
73 | class IdentifierIndexReaderTrait { | |||
74 | public: | |||
75 | typedef StringRef external_key_type; | |||
76 | typedef StringRef internal_key_type; | |||
77 | typedef SmallVector<unsigned, 2> data_type; | |||
78 | typedef unsigned hash_value_type; | |||
79 | typedef unsigned offset_type; | |||
80 | ||||
81 | static bool EqualKey(const internal_key_type& a, const internal_key_type& b) { | |||
82 | return a == b; | |||
83 | } | |||
84 | ||||
85 | static hash_value_type ComputeHash(const internal_key_type& a) { | |||
86 | return llvm::djbHash(a); | |||
87 | } | |||
88 | ||||
89 | static std::pair<unsigned, unsigned> | |||
90 | ReadKeyDataLength(const unsigned char*& d) { | |||
91 | using namespace llvm::support; | |||
92 | unsigned KeyLen = endian::readNext<uint16_t, little, unaligned>(d); | |||
93 | unsigned DataLen = endian::readNext<uint16_t, little, unaligned>(d); | |||
94 | return std::make_pair(KeyLen, DataLen); | |||
95 | } | |||
96 | ||||
97 | static const internal_key_type& | |||
98 | GetInternalKey(const external_key_type& x) { return x; } | |||
99 | ||||
100 | static const external_key_type& | |||
101 | GetExternalKey(const internal_key_type& x) { return x; } | |||
102 | ||||
103 | static internal_key_type ReadKey(const unsigned char* d, unsigned n) { | |||
104 | return StringRef((const char *)d, n); | |||
105 | } | |||
106 | ||||
107 | static data_type ReadData(const internal_key_type& k, | |||
108 | const unsigned char* d, | |||
109 | unsigned DataLen) { | |||
110 | using namespace llvm::support; | |||
111 | ||||
112 | data_type Result; | |||
113 | while (DataLen > 0) { | |||
114 | unsigned ID = endian::readNext<uint32_t, little, unaligned>(d); | |||
115 | Result.push_back(ID); | |||
116 | DataLen -= 4; | |||
117 | } | |||
118 | ||||
119 | return Result; | |||
120 | } | |||
121 | }; | |||
122 | ||||
123 | typedef llvm::OnDiskIterableChainedHashTable<IdentifierIndexReaderTrait> | |||
124 | IdentifierIndexTable; | |||
125 | ||||
126 | } | |||
127 | ||||
128 | GlobalModuleIndex::GlobalModuleIndex(std::unique_ptr<llvm::MemoryBuffer> Buffer, | |||
129 | llvm::BitstreamCursor Cursor) | |||
130 | : Buffer(std::move(Buffer)), IdentifierIndex(), NumIdentifierLookups(), | |||
131 | NumIdentifierLookupHits() { | |||
132 | auto Fail = [&Buffer](llvm::Error &&Err) { | |||
133 | report_fatal_error("Module index '" + Buffer->getBufferIdentifier() + | |||
134 | "' failed: " + toString(std::move(Err))); | |||
135 | }; | |||
136 | ||||
137 | llvm::TimeTraceScope TimeScope("Module LoadIndex", StringRef("")); | |||
138 | // Read the global index. | |||
139 | bool InGlobalIndexBlock = false; | |||
140 | bool Done = false; | |||
141 | while (!Done) { | |||
142 | llvm::BitstreamEntry Entry; | |||
143 | if (Expected<llvm::BitstreamEntry> Res = Cursor.advance()) | |||
144 | Entry = Res.get(); | |||
145 | else | |||
146 | Fail(Res.takeError()); | |||
147 | ||||
148 | switch (Entry.Kind) { | |||
149 | case llvm::BitstreamEntry::Error: | |||
150 | return; | |||
151 | ||||
152 | case llvm::BitstreamEntry::EndBlock: | |||
153 | if (InGlobalIndexBlock) { | |||
154 | InGlobalIndexBlock = false; | |||
155 | Done = true; | |||
156 | continue; | |||
157 | } | |||
158 | return; | |||
159 | ||||
160 | ||||
161 | case llvm::BitstreamEntry::Record: | |||
162 | // Entries in the global index block are handled below. | |||
163 | if (InGlobalIndexBlock) | |||
164 | break; | |||
165 | ||||
166 | return; | |||
167 | ||||
168 | case llvm::BitstreamEntry::SubBlock: | |||
169 | if (!InGlobalIndexBlock && Entry.ID == GLOBAL_INDEX_BLOCK_ID) { | |||
170 | if (llvm::Error Err = Cursor.EnterSubBlock(GLOBAL_INDEX_BLOCK_ID)) | |||
171 | Fail(std::move(Err)); | |||
172 | InGlobalIndexBlock = true; | |||
173 | } else if (llvm::Error Err = Cursor.SkipBlock()) | |||
174 | Fail(std::move(Err)); | |||
175 | continue; | |||
176 | } | |||
177 | ||||
178 | SmallVector<uint64_t, 64> Record; | |||
179 | StringRef Blob; | |||
180 | Expected<unsigned> MaybeIndexRecord = | |||
181 | Cursor.readRecord(Entry.ID, Record, &Blob); | |||
182 | if (!MaybeIndexRecord) | |||
183 | Fail(MaybeIndexRecord.takeError()); | |||
184 | IndexRecordTypes IndexRecord = | |||
185 | static_cast<IndexRecordTypes>(MaybeIndexRecord.get()); | |||
186 | switch (IndexRecord) { | |||
187 | case INDEX_METADATA: | |||
188 | // Make sure that the version matches. | |||
189 | if (Record.size() < 1 || Record[0] != CurrentVersion) | |||
190 | return; | |||
191 | break; | |||
192 | ||||
193 | case MODULE: { | |||
194 | unsigned Idx = 0; | |||
195 | unsigned ID = Record[Idx++]; | |||
196 | ||||
197 | // Make room for this module's information. | |||
198 | if (ID == Modules.size()) | |||
199 | Modules.push_back(ModuleInfo()); | |||
200 | else | |||
201 | Modules.resize(ID + 1); | |||
202 | ||||
203 | // Size/modification time for this module file at the time the | |||
204 | // global index was built. | |||
205 | Modules[ID].Size = Record[Idx++]; | |||
206 | Modules[ID].ModTime = Record[Idx++]; | |||
207 | ||||
208 | // File name. | |||
209 | unsigned NameLen = Record[Idx++]; | |||
210 | Modules[ID].FileName.assign(Record.begin() + Idx, | |||
211 | Record.begin() + Idx + NameLen); | |||
212 | Idx += NameLen; | |||
213 | ||||
214 | // Dependencies | |||
215 | unsigned NumDeps = Record[Idx++]; | |||
216 | Modules[ID].Dependencies.insert(Modules[ID].Dependencies.end(), | |||
217 | Record.begin() + Idx, | |||
218 | Record.begin() + Idx + NumDeps); | |||
219 | Idx += NumDeps; | |||
220 | ||||
221 | // Make sure we're at the end of the record. | |||
222 | assert(Idx == Record.size() && "More module info?")((Idx == Record.size() && "More module info?") ? static_cast <void> (0) : __assert_fail ("Idx == Record.size() && \"More module info?\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Serialization/GlobalModuleIndex.cpp" , 222, __PRETTY_FUNCTION__)); | |||
223 | ||||
224 | // Record this module as an unresolved module. | |||
225 | // FIXME: this doesn't work correctly for module names containing path | |||
226 | // separators. | |||
227 | StringRef ModuleName = llvm::sys::path::stem(Modules[ID].FileName); | |||
228 | // Remove the -<hash of ModuleMapPath> | |||
229 | ModuleName = ModuleName.rsplit('-').first; | |||
230 | UnresolvedModules[ModuleName] = ID; | |||
231 | break; | |||
232 | } | |||
233 | ||||
234 | case IDENTIFIER_INDEX: | |||
235 | // Wire up the identifier index. | |||
236 | if (Record[0]) { | |||
237 | IdentifierIndex = IdentifierIndexTable::Create( | |||
238 | (const unsigned char *)Blob.data() + Record[0], | |||
239 | (const unsigned char *)Blob.data() + sizeof(uint32_t), | |||
240 | (const unsigned char *)Blob.data(), IdentifierIndexReaderTrait()); | |||
241 | } | |||
242 | break; | |||
243 | } | |||
244 | } | |||
245 | } | |||
246 | ||||
247 | GlobalModuleIndex::~GlobalModuleIndex() { | |||
248 | delete static_cast<IdentifierIndexTable *>(IdentifierIndex); | |||
249 | } | |||
250 | ||||
251 | std::pair<GlobalModuleIndex *, llvm::Error> | |||
252 | GlobalModuleIndex::readIndex(StringRef Path) { | |||
253 | // Load the index file, if it's there. | |||
254 | llvm::SmallString<128> IndexPath; | |||
255 | IndexPath += Path; | |||
256 | llvm::sys::path::append(IndexPath, IndexFileName); | |||
257 | ||||
258 | llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> BufferOrErr = | |||
259 | llvm::MemoryBuffer::getFile(IndexPath.c_str()); | |||
260 | if (!BufferOrErr) | |||
261 | return std::make_pair(nullptr, | |||
262 | llvm::errorCodeToError(BufferOrErr.getError())); | |||
263 | std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(BufferOrErr.get()); | |||
264 | ||||
265 | /// The main bitstream cursor for the main block. | |||
266 | llvm::BitstreamCursor Cursor(*Buffer); | |||
267 | ||||
268 | // Sniff for the signature. | |||
269 | for (unsigned char C : {'B', 'C', 'G', 'I'}) { | |||
270 | if (Expected<llvm::SimpleBitstreamCursor::word_t> Res = Cursor.Read(8)) { | |||
271 | if (Res.get() != C) | |||
272 | return std::make_pair( | |||
273 | nullptr, llvm::createStringError(std::errc::illegal_byte_sequence, | |||
274 | "expected signature BCGI")); | |||
275 | } else | |||
276 | return std::make_pair(nullptr, Res.takeError()); | |||
277 | } | |||
278 | ||||
279 | return std::make_pair(new GlobalModuleIndex(std::move(Buffer), Cursor), | |||
280 | llvm::Error::success()); | |||
281 | } | |||
282 | ||||
283 | void | |||
284 | GlobalModuleIndex::getKnownModules(SmallVectorImpl<ModuleFile *> &ModuleFiles) { | |||
285 | ModuleFiles.clear(); | |||
286 | for (unsigned I = 0, N = Modules.size(); I != N; ++I) { | |||
287 | if (ModuleFile *MF = Modules[I].File) | |||
288 | ModuleFiles.push_back(MF); | |||
289 | } | |||
290 | } | |||
291 | ||||
292 | void GlobalModuleIndex::getModuleDependencies( | |||
293 | ModuleFile *File, | |||
294 | SmallVectorImpl<ModuleFile *> &Dependencies) { | |||
295 | // Look for information about this module file. | |||
296 | llvm::DenseMap<ModuleFile *, unsigned>::iterator Known | |||
297 | = ModulesByFile.find(File); | |||
298 | if (Known == ModulesByFile.end()) | |||
299 | return; | |||
300 | ||||
301 | // Record dependencies. | |||
302 | Dependencies.clear(); | |||
303 | ArrayRef<unsigned> StoredDependencies = Modules[Known->second].Dependencies; | |||
304 | for (unsigned I = 0, N = StoredDependencies.size(); I != N; ++I) { | |||
305 | if (ModuleFile *MF = Modules[I].File) | |||
306 | Dependencies.push_back(MF); | |||
307 | } | |||
308 | } | |||
309 | ||||
310 | bool GlobalModuleIndex::lookupIdentifier(StringRef Name, HitSet &Hits) { | |||
311 | Hits.clear(); | |||
312 | ||||
313 | // If there's no identifier index, there is nothing we can do. | |||
314 | if (!IdentifierIndex) | |||
315 | return false; | |||
316 | ||||
317 | // Look into the identifier index. | |||
318 | ++NumIdentifierLookups; | |||
319 | IdentifierIndexTable &Table | |||
320 | = *static_cast<IdentifierIndexTable *>(IdentifierIndex); | |||
321 | IdentifierIndexTable::iterator Known = Table.find(Name); | |||
322 | if (Known == Table.end()) { | |||
323 | return true; | |||
324 | } | |||
325 | ||||
326 | SmallVector<unsigned, 2> ModuleIDs = *Known; | |||
327 | for (unsigned I = 0, N = ModuleIDs.size(); I != N; ++I) { | |||
328 | if (ModuleFile *MF = Modules[ModuleIDs[I]].File) | |||
329 | Hits.insert(MF); | |||
330 | } | |||
331 | ||||
332 | ++NumIdentifierLookupHits; | |||
333 | return true; | |||
334 | } | |||
335 | ||||
336 | bool GlobalModuleIndex::loadedModuleFile(ModuleFile *File) { | |||
337 | // Look for the module in the global module index based on the module name. | |||
338 | StringRef Name = File->ModuleName; | |||
339 | llvm::StringMap<unsigned>::iterator Known = UnresolvedModules.find(Name); | |||
340 | if (Known == UnresolvedModules.end()) { | |||
341 | return true; | |||
342 | } | |||
343 | ||||
344 | // Rectify this module with the global module index. | |||
345 | ModuleInfo &Info = Modules[Known->second]; | |||
346 | ||||
347 | // If the size and modification time match what we expected, record this | |||
348 | // module file. | |||
349 | bool Failed = true; | |||
350 | if (File->File->getSize() == Info.Size && | |||
351 | File->File->getModificationTime() == Info.ModTime) { | |||
352 | Info.File = File; | |||
353 | ModulesByFile[File] = Known->second; | |||
354 | ||||
355 | Failed = false; | |||
356 | } | |||
357 | ||||
358 | // One way or another, we have resolved this module file. | |||
359 | UnresolvedModules.erase(Known); | |||
360 | return Failed; | |||
361 | } | |||
362 | ||||
363 | void GlobalModuleIndex::printStats() { | |||
364 | std::fprintf(stderrstderr, "*** Global Module Index Statistics:\n"); | |||
365 | if (NumIdentifierLookups) { | |||
366 | fprintf(stderrstderr, " %u / %u identifier lookups succeeded (%f%%)\n", | |||
367 | NumIdentifierLookupHits, NumIdentifierLookups, | |||
368 | (double)NumIdentifierLookupHits*100.0/NumIdentifierLookups); | |||
369 | } | |||
370 | std::fprintf(stderrstderr, "\n"); | |||
371 | } | |||
372 | ||||
373 | LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void GlobalModuleIndex::dump() { | |||
374 | llvm::errs() << "*** Global Module Index Dump:\n"; | |||
375 | llvm::errs() << "Module files:\n"; | |||
376 | for (auto &MI : Modules) { | |||
377 | llvm::errs() << "** " << MI.FileName << "\n"; | |||
378 | if (MI.File) | |||
379 | MI.File->dump(); | |||
380 | else | |||
381 | llvm::errs() << "\n"; | |||
382 | } | |||
383 | llvm::errs() << "\n"; | |||
384 | } | |||
385 | ||||
386 | //----------------------------------------------------------------------------// | |||
387 | // Global module index writer. | |||
388 | //----------------------------------------------------------------------------// | |||
389 | ||||
390 | namespace { | |||
391 | /// Provides information about a specific module file. | |||
392 | struct ModuleFileInfo { | |||
393 | /// The numberic ID for this module file. | |||
394 | unsigned ID; | |||
395 | ||||
396 | /// The set of modules on which this module depends. Each entry is | |||
397 | /// a module ID. | |||
398 | SmallVector<unsigned, 4> Dependencies; | |||
399 | ASTFileSignature Signature; | |||
400 | }; | |||
401 | ||||
402 | struct ImportedModuleFileInfo { | |||
403 | off_t StoredSize; | |||
404 | time_t StoredModTime; | |||
405 | ASTFileSignature StoredSignature; | |||
406 | ImportedModuleFileInfo(off_t Size, time_t ModTime, ASTFileSignature Sig) | |||
407 | : StoredSize(Size), StoredModTime(ModTime), StoredSignature(Sig) {} | |||
408 | }; | |||
409 | ||||
410 | /// Builder that generates the global module index file. | |||
411 | class GlobalModuleIndexBuilder { | |||
412 | FileManager &FileMgr; | |||
413 | const PCHContainerReader &PCHContainerRdr; | |||
414 | ||||
415 | /// Mapping from files to module file information. | |||
416 | typedef llvm::MapVector<const FileEntry *, ModuleFileInfo> ModuleFilesMap; | |||
417 | ||||
418 | /// Information about each of the known module files. | |||
419 | ModuleFilesMap ModuleFiles; | |||
420 | ||||
421 | /// Mapping from the imported module file to the imported | |||
422 | /// information. | |||
423 | typedef std::multimap<const FileEntry *, ImportedModuleFileInfo> | |||
424 | ImportedModuleFilesMap; | |||
425 | ||||
426 | /// Information about each importing of a module file. | |||
427 | ImportedModuleFilesMap ImportedModuleFiles; | |||
428 | ||||
429 | /// Mapping from identifiers to the list of module file IDs that | |||
430 | /// consider this identifier to be interesting. | |||
431 | typedef llvm::StringMap<SmallVector<unsigned, 2> > InterestingIdentifierMap; | |||
432 | ||||
433 | /// A mapping from all interesting identifiers to the set of module | |||
434 | /// files in which those identifiers are considered interesting. | |||
435 | InterestingIdentifierMap InterestingIdentifiers; | |||
436 | ||||
437 | /// Write the block-info block for the global module index file. | |||
438 | void emitBlockInfoBlock(llvm::BitstreamWriter &Stream); | |||
439 | ||||
440 | /// Retrieve the module file information for the given file. | |||
441 | ModuleFileInfo &getModuleFileInfo(const FileEntry *File) { | |||
442 | llvm::MapVector<const FileEntry *, ModuleFileInfo>::iterator Known | |||
443 | = ModuleFiles.find(File); | |||
444 | if (Known != ModuleFiles.end()) | |||
445 | return Known->second; | |||
446 | ||||
447 | unsigned NewID = ModuleFiles.size(); | |||
448 | ModuleFileInfo &Info = ModuleFiles[File]; | |||
449 | Info.ID = NewID; | |||
450 | return Info; | |||
451 | } | |||
452 | ||||
453 | public: | |||
454 | explicit GlobalModuleIndexBuilder( | |||
455 | FileManager &FileMgr, const PCHContainerReader &PCHContainerRdr) | |||
456 | : FileMgr(FileMgr), PCHContainerRdr(PCHContainerRdr) {} | |||
457 | ||||
458 | /// Load the contents of the given module file into the builder. | |||
459 | llvm::Error loadModuleFile(const FileEntry *File); | |||
460 | ||||
461 | /// Write the index to the given bitstream. | |||
462 | /// \returns true if an error occurred, false otherwise. | |||
463 | bool writeIndex(llvm::BitstreamWriter &Stream); | |||
464 | }; | |||
465 | } | |||
466 | ||||
467 | static void emitBlockID(unsigned ID, const char *Name, | |||
468 | llvm::BitstreamWriter &Stream, | |||
469 | SmallVectorImpl<uint64_t> &Record) { | |||
470 | Record.clear(); | |||
471 | Record.push_back(ID); | |||
472 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, Record); | |||
473 | ||||
474 | // Emit the block name if present. | |||
475 | if (!Name || Name[0] == 0) return; | |||
476 | Record.clear(); | |||
477 | while (*Name) | |||
478 | Record.push_back(*Name++); | |||
479 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, Record); | |||
480 | } | |||
481 | ||||
482 | static void emitRecordID(unsigned ID, const char *Name, | |||
483 | llvm::BitstreamWriter &Stream, | |||
484 | SmallVectorImpl<uint64_t> &Record) { | |||
485 | Record.clear(); | |||
486 | Record.push_back(ID); | |||
487 | while (*Name) | |||
488 | Record.push_back(*Name++); | |||
489 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, Record); | |||
490 | } | |||
491 | ||||
492 | void | |||
493 | GlobalModuleIndexBuilder::emitBlockInfoBlock(llvm::BitstreamWriter &Stream) { | |||
494 | SmallVector<uint64_t, 64> Record; | |||
495 | Stream.EnterBlockInfoBlock(); | |||
496 | ||||
497 | #define BLOCK(X) emitBlockID(X ## _ID, #X, Stream, Record) | |||
498 | #define RECORD(X) emitRecordID(X, #X, Stream, Record) | |||
499 | BLOCK(GLOBAL_INDEX_BLOCK); | |||
500 | RECORD(INDEX_METADATA); | |||
501 | RECORD(MODULE); | |||
502 | RECORD(IDENTIFIER_INDEX); | |||
503 | #undef RECORD | |||
504 | #undef BLOCK | |||
505 | ||||
506 | Stream.ExitBlock(); | |||
507 | } | |||
508 | ||||
509 | namespace { | |||
510 | class InterestingASTIdentifierLookupTrait | |||
511 | : public serialization::reader::ASTIdentifierLookupTraitBase { | |||
512 | ||||
513 | public: | |||
514 | /// The identifier and whether it is "interesting". | |||
515 | typedef std::pair<StringRef, bool> data_type; | |||
516 | ||||
517 | data_type ReadData(const internal_key_type& k, | |||
518 | const unsigned char* d, | |||
519 | unsigned DataLen) { | |||
520 | // The first bit indicates whether this identifier is interesting. | |||
521 | // That's all we care about. | |||
522 | using namespace llvm::support; | |||
523 | unsigned RawID = endian::readNext<uint32_t, little, unaligned>(d); | |||
524 | bool IsInteresting = RawID & 0x01; | |||
525 | return std::make_pair(k, IsInteresting); | |||
526 | } | |||
527 | }; | |||
528 | } | |||
529 | ||||
530 | llvm::Error GlobalModuleIndexBuilder::loadModuleFile(const FileEntry *File) { | |||
531 | // Open the module file. | |||
532 | ||||
533 | auto Buffer = FileMgr.getBufferForFile(File, /*isVolatile=*/true); | |||
534 | if (!Buffer) | |||
| ||||
535 | return llvm::createStringError(Buffer.getError(), | |||
536 | "failed getting buffer for module file"); | |||
537 | ||||
538 | // Initialize the input stream | |||
539 | llvm::BitstreamCursor InStream(PCHContainerRdr.ExtractPCH(**Buffer)); | |||
540 | ||||
541 | // Sniff for the signature. | |||
542 | for (unsigned char C : {'C', 'P', 'C', 'H'}) | |||
543 | if (Expected<llvm::SimpleBitstreamCursor::word_t> Res = InStream.Read(8)) { | |||
544 | if (Res.get() != C) | |||
545 | return llvm::createStringError(std::errc::illegal_byte_sequence, | |||
546 | "expected signature CPCH"); | |||
547 | } else | |||
548 | return Res.takeError(); | |||
549 | ||||
550 | // Record this module file and assign it a unique ID (if it doesn't have | |||
551 | // one already). | |||
552 | unsigned ID = getModuleFileInfo(File).ID; | |||
553 | ||||
554 | // Search for the blocks and records we care about. | |||
555 | enum { Other, ControlBlock, ASTBlock, DiagnosticOptionsBlock } State = Other; | |||
556 | bool Done = false; | |||
557 | while (!Done) { | |||
558 | Expected<llvm::BitstreamEntry> MaybeEntry = InStream.advance(); | |||
559 | if (!MaybeEntry) | |||
560 | return MaybeEntry.takeError(); | |||
561 | llvm::BitstreamEntry Entry = MaybeEntry.get(); | |||
562 | ||||
563 | switch (Entry.Kind) { | |||
564 | case llvm::BitstreamEntry::Error: | |||
565 | Done = true; | |||
566 | continue; | |||
567 | ||||
568 | case llvm::BitstreamEntry::Record: | |||
569 | // In the 'other' state, just skip the record. We don't care. | |||
570 | if (State == Other) { | |||
571 | if (llvm::Expected<unsigned> Skipped = InStream.skipRecord(Entry.ID)) | |||
572 | continue; | |||
573 | else | |||
574 | return Skipped.takeError(); | |||
575 | } | |||
576 | ||||
577 | // Handle potentially-interesting records below. | |||
578 | break; | |||
579 | ||||
580 | case llvm::BitstreamEntry::SubBlock: | |||
581 | if (Entry.ID == CONTROL_BLOCK_ID) { | |||
582 | if (llvm::Error Err = InStream.EnterSubBlock(CONTROL_BLOCK_ID)) | |||
583 | return Err; | |||
584 | ||||
585 | // Found the control block. | |||
586 | State = ControlBlock; | |||
587 | continue; | |||
588 | } | |||
589 | ||||
590 | if (Entry.ID == AST_BLOCK_ID) { | |||
591 | if (llvm::Error Err = InStream.EnterSubBlock(AST_BLOCK_ID)) | |||
592 | return Err; | |||
593 | ||||
594 | // Found the AST block. | |||
595 | State = ASTBlock; | |||
596 | continue; | |||
597 | } | |||
598 | ||||
599 | if (Entry.ID == UNHASHED_CONTROL_BLOCK_ID) { | |||
600 | if (llvm::Error Err = InStream.EnterSubBlock(UNHASHED_CONTROL_BLOCK_ID)) | |||
601 | return Err; | |||
602 | ||||
603 | // Found the Diagnostic Options block. | |||
604 | State = DiagnosticOptionsBlock; | |||
605 | continue; | |||
606 | } | |||
607 | ||||
608 | if (llvm::Error Err = InStream.SkipBlock()) | |||
609 | return Err; | |||
610 | ||||
611 | continue; | |||
612 | ||||
613 | case llvm::BitstreamEntry::EndBlock: | |||
614 | State = Other; | |||
615 | continue; | |||
616 | } | |||
617 | ||||
618 | // Read the given record. | |||
619 | SmallVector<uint64_t, 64> Record; | |||
620 | StringRef Blob; | |||
621 | Expected<unsigned> MaybeCode = InStream.readRecord(Entry.ID, Record, &Blob); | |||
622 | if (!MaybeCode) | |||
623 | return MaybeCode.takeError(); | |||
624 | unsigned Code = MaybeCode.get(); | |||
625 | ||||
626 | // Handle module dependencies. | |||
627 | if (State == ControlBlock && Code == IMPORTS) { | |||
628 | // Load each of the imported PCH files. | |||
629 | unsigned Idx = 0, N = Record.size(); | |||
630 | while (Idx < N) { | |||
631 | // Read information about the AST file. | |||
632 | ||||
633 | // Skip the imported kind | |||
634 | ++Idx; | |||
635 | ||||
636 | // Skip the import location | |||
637 | ++Idx; | |||
638 | ||||
639 | // Load stored size/modification time. | |||
640 | off_t StoredSize = (off_t)Record[Idx++]; | |||
641 | time_t StoredModTime = (time_t)Record[Idx++]; | |||
642 | ||||
643 | // Skip the stored signature. | |||
644 | // FIXME: we could read the signature out of the import and validate it. | |||
645 | ASTFileSignature StoredSignature = { | |||
646 | {{(uint32_t)Record[Idx++], (uint32_t)Record[Idx++], | |||
647 | (uint32_t)Record[Idx++], (uint32_t)Record[Idx++], | |||
648 | (uint32_t)Record[Idx++]}}}; | |||
649 | ||||
650 | // Skip the module name (currently this is only used for prebuilt | |||
651 | // modules while here we are only dealing with cached). | |||
652 | Idx += Record[Idx] + 1; | |||
653 | ||||
654 | // Retrieve the imported file name. | |||
655 | unsigned Length = Record[Idx++]; | |||
656 | SmallString<128> ImportedFile(Record.begin() + Idx, | |||
657 | Record.begin() + Idx + Length); | |||
658 | Idx += Length; | |||
659 | ||||
660 | // Find the imported module file. | |||
661 | auto DependsOnFile | |||
662 | = FileMgr.getFile(ImportedFile, /*OpenFile=*/false, | |||
663 | /*CacheFailure=*/false); | |||
664 | ||||
665 | if (!DependsOnFile) | |||
666 | return llvm::createStringError(std::errc::bad_file_descriptor, | |||
667 | "imported file \"%s\" not found", | |||
668 | ImportedFile.c_str()); | |||
669 | ||||
670 | // Save the information in ImportedModuleFileInfo so we can verify after | |||
671 | // loading all pcms. | |||
672 | ImportedModuleFiles.insert(std::make_pair( | |||
673 | *DependsOnFile, ImportedModuleFileInfo(StoredSize, StoredModTime, | |||
674 | StoredSignature))); | |||
675 | ||||
676 | // Record the dependency. | |||
677 | unsigned DependsOnID = getModuleFileInfo(*DependsOnFile).ID; | |||
678 | getModuleFileInfo(File).Dependencies.push_back(DependsOnID); | |||
679 | } | |||
680 | ||||
681 | continue; | |||
682 | } | |||
683 | ||||
684 | // Handle the identifier table | |||
685 | if (State == ASTBlock && Code == IDENTIFIER_TABLE && Record[0] > 0) { | |||
686 | typedef llvm::OnDiskIterableChainedHashTable< | |||
687 | InterestingASTIdentifierLookupTrait> InterestingIdentifierTable; | |||
688 | std::unique_ptr<InterestingIdentifierTable> Table( | |||
689 | InterestingIdentifierTable::Create( | |||
690 | (const unsigned char *)Blob.data() + Record[0], | |||
691 | (const unsigned char *)Blob.data() + sizeof(uint32_t), | |||
692 | (const unsigned char *)Blob.data())); | |||
693 | for (InterestingIdentifierTable::data_iterator D = Table->data_begin(), | |||
694 | DEnd = Table->data_end(); | |||
695 | D != DEnd; ++D) { | |||
696 | std::pair<StringRef, bool> Ident = *D; | |||
697 | if (Ident.second) | |||
698 | InterestingIdentifiers[Ident.first].push_back(ID); | |||
699 | else | |||
700 | (void)InterestingIdentifiers[Ident.first]; | |||
701 | } | |||
702 | } | |||
703 | ||||
704 | // Get Signature. | |||
705 | if (State == DiagnosticOptionsBlock && Code == SIGNATURE) | |||
706 | getModuleFileInfo(File).Signature = { | |||
707 | {{(uint32_t)Record[0], (uint32_t)Record[1], (uint32_t)Record[2], | |||
708 | (uint32_t)Record[3], (uint32_t)Record[4]}}}; | |||
709 | ||||
710 | // We don't care about this record. | |||
711 | } | |||
712 | ||||
713 | return llvm::Error::success(); | |||
714 | } | |||
715 | ||||
716 | namespace { | |||
717 | ||||
718 | /// Trait used to generate the identifier index as an on-disk hash | |||
719 | /// table. | |||
720 | class IdentifierIndexWriterTrait { | |||
721 | public: | |||
722 | typedef StringRef key_type; | |||
723 | typedef StringRef key_type_ref; | |||
724 | typedef SmallVector<unsigned, 2> data_type; | |||
725 | typedef const SmallVector<unsigned, 2> &data_type_ref; | |||
726 | typedef unsigned hash_value_type; | |||
727 | typedef unsigned offset_type; | |||
728 | ||||
729 | static hash_value_type ComputeHash(key_type_ref Key) { | |||
730 | return llvm::djbHash(Key); | |||
731 | } | |||
732 | ||||
733 | std::pair<unsigned,unsigned> | |||
734 | EmitKeyDataLength(raw_ostream& Out, key_type_ref Key, data_type_ref Data) { | |||
735 | using namespace llvm::support; | |||
736 | endian::Writer LE(Out, little); | |||
737 | unsigned KeyLen = Key.size(); | |||
738 | unsigned DataLen = Data.size() * 4; | |||
739 | LE.write<uint16_t>(KeyLen); | |||
740 | LE.write<uint16_t>(DataLen); | |||
741 | return std::make_pair(KeyLen, DataLen); | |||
742 | } | |||
743 | ||||
744 | void EmitKey(raw_ostream& Out, key_type_ref Key, unsigned KeyLen) { | |||
745 | Out.write(Key.data(), KeyLen); | |||
746 | } | |||
747 | ||||
748 | void EmitData(raw_ostream& Out, key_type_ref Key, data_type_ref Data, | |||
749 | unsigned DataLen) { | |||
750 | using namespace llvm::support; | |||
751 | for (unsigned I = 0, N = Data.size(); I != N; ++I) | |||
752 | endian::write<uint32_t>(Out, Data[I], little); | |||
753 | } | |||
754 | }; | |||
755 | ||||
756 | } | |||
757 | ||||
758 | bool GlobalModuleIndexBuilder::writeIndex(llvm::BitstreamWriter &Stream) { | |||
759 | for (auto MapEntry : ImportedModuleFiles) { | |||
760 | auto *File = MapEntry.first; | |||
761 | ImportedModuleFileInfo &Info = MapEntry.second; | |||
762 | if (getModuleFileInfo(File).Signature) { | |||
763 | if (getModuleFileInfo(File).Signature != Info.StoredSignature) | |||
764 | // Verify Signature. | |||
765 | return true; | |||
766 | } else if (Info.StoredSize != File->getSize() || | |||
767 | Info.StoredModTime != File->getModificationTime()) | |||
768 | // Verify Size and ModTime. | |||
769 | return true; | |||
770 | } | |||
771 | ||||
772 | using namespace llvm; | |||
773 | llvm::TimeTraceScope TimeScope("Module WriteIndex", StringRef("")); | |||
774 | ||||
775 | // Emit the file header. | |||
776 | Stream.Emit((unsigned)'B', 8); | |||
777 | Stream.Emit((unsigned)'C', 8); | |||
778 | Stream.Emit((unsigned)'G', 8); | |||
779 | Stream.Emit((unsigned)'I', 8); | |||
780 | ||||
781 | // Write the block-info block, which describes the records in this bitcode | |||
782 | // file. | |||
783 | emitBlockInfoBlock(Stream); | |||
784 | ||||
785 | Stream.EnterSubblock(GLOBAL_INDEX_BLOCK_ID, 3); | |||
786 | ||||
787 | // Write the metadata. | |||
788 | SmallVector<uint64_t, 2> Record; | |||
789 | Record.push_back(CurrentVersion); | |||
790 | Stream.EmitRecord(INDEX_METADATA, Record); | |||
791 | ||||
792 | // Write the set of known module files. | |||
793 | for (ModuleFilesMap::iterator M = ModuleFiles.begin(), | |||
794 | MEnd = ModuleFiles.end(); | |||
795 | M != MEnd; ++M) { | |||
796 | Record.clear(); | |||
797 | Record.push_back(M->second.ID); | |||
798 | Record.push_back(M->first->getSize()); | |||
799 | Record.push_back(M->first->getModificationTime()); | |||
800 | ||||
801 | // File name | |||
802 | StringRef Name(M->first->getName()); | |||
803 | Record.push_back(Name.size()); | |||
804 | Record.append(Name.begin(), Name.end()); | |||
805 | ||||
806 | // Dependencies | |||
807 | Record.push_back(M->second.Dependencies.size()); | |||
808 | Record.append(M->second.Dependencies.begin(), M->second.Dependencies.end()); | |||
809 | Stream.EmitRecord(MODULE, Record); | |||
810 | } | |||
811 | ||||
812 | // Write the identifier -> module file mapping. | |||
813 | { | |||
814 | llvm::OnDiskChainedHashTableGenerator<IdentifierIndexWriterTrait> Generator; | |||
815 | IdentifierIndexWriterTrait Trait; | |||
816 | ||||
817 | // Populate the hash table. | |||
818 | for (InterestingIdentifierMap::iterator I = InterestingIdentifiers.begin(), | |||
819 | IEnd = InterestingIdentifiers.end(); | |||
820 | I != IEnd; ++I) { | |||
821 | Generator.insert(I->first(), I->second, Trait); | |||
822 | } | |||
823 | ||||
824 | // Create the on-disk hash table in a buffer. | |||
825 | SmallString<4096> IdentifierTable; | |||
826 | uint32_t BucketOffset; | |||
827 | { | |||
828 | using namespace llvm::support; | |||
829 | llvm::raw_svector_ostream Out(IdentifierTable); | |||
830 | // Make sure that no bucket is at offset 0 | |||
831 | endian::write<uint32_t>(Out, 0, little); | |||
832 | BucketOffset = Generator.Emit(Out, Trait); | |||
833 | } | |||
834 | ||||
835 | // Create a blob abbreviation | |||
836 | auto Abbrev = std::make_shared<BitCodeAbbrev>(); | |||
837 | Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_INDEX)); | |||
838 | Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); | |||
839 | Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); | |||
840 | unsigned IDTableAbbrev = Stream.EmitAbbrev(std::move(Abbrev)); | |||
841 | ||||
842 | // Write the identifier table | |||
843 | uint64_t Record[] = {IDENTIFIER_INDEX, BucketOffset}; | |||
844 | Stream.EmitRecordWithBlob(IDTableAbbrev, Record, IdentifierTable); | |||
845 | } | |||
846 | ||||
847 | Stream.ExitBlock(); | |||
848 | return false; | |||
849 | } | |||
850 | ||||
851 | llvm::Error | |||
852 | GlobalModuleIndex::writeIndex(FileManager &FileMgr, | |||
853 | const PCHContainerReader &PCHContainerRdr, | |||
854 | StringRef Path) { | |||
855 | llvm::SmallString<128> IndexPath; | |||
856 | IndexPath += Path; | |||
857 | llvm::sys::path::append(IndexPath, IndexFileName); | |||
858 | ||||
859 | // Coordinate building the global index file with other processes that might | |||
860 | // try to do the same. | |||
861 | llvm::LockFileManager Locked(IndexPath); | |||
862 | switch (Locked) { | |||
863 | case llvm::LockFileManager::LFS_Error: | |||
864 | return llvm::createStringError(std::errc::io_error, "LFS error"); | |||
865 | ||||
866 | case llvm::LockFileManager::LFS_Owned: | |||
867 | // We're responsible for building the index ourselves. Do so below. | |||
868 | break; | |||
869 | ||||
870 | case llvm::LockFileManager::LFS_Shared: | |||
871 | // Someone else is responsible for building the index. We don't care | |||
872 | // when they finish, so we're done. | |||
873 | return llvm::createStringError(std::errc::device_or_resource_busy, | |||
874 | "someone else is building the index"); | |||
875 | } | |||
876 | ||||
877 | // The module index builder. | |||
878 | GlobalModuleIndexBuilder Builder(FileMgr, PCHContainerRdr); | |||
879 | ||||
880 | // Load each of the module files. | |||
881 | std::error_code EC; | |||
882 | for (llvm::sys::fs::directory_iterator D(Path, EC), DEnd; | |||
883 | D != DEnd && !EC; | |||
884 | D.increment(EC)) { | |||
885 | // If this isn't a module file, we don't care. | |||
886 | if (llvm::sys::path::extension(D->path()) != ".pcm") { | |||
887 | // ... unless it's a .pcm.lock file, which indicates that someone is | |||
888 | // in the process of rebuilding a module. They'll rebuild the index | |||
889 | // at the end of that translation unit, so we don't have to. | |||
890 | if (llvm::sys::path::extension(D->path()) == ".pcm.lock") | |||
891 | return llvm::createStringError(std::errc::device_or_resource_busy, | |||
892 | "someone else is building the index"); | |||
893 | ||||
894 | continue; | |||
895 | } | |||
896 | ||||
897 | // If we can't find the module file, skip it. | |||
898 | auto ModuleFile = FileMgr.getFile(D->path()); | |||
899 | if (!ModuleFile) | |||
900 | continue; | |||
901 | ||||
902 | // Load this module file. | |||
903 | if (llvm::Error Err = Builder.loadModuleFile(*ModuleFile)) | |||
904 | return Err; | |||
905 | } | |||
906 | ||||
907 | // The output buffer, into which the global index will be written. | |||
908 | SmallVector<char, 16> OutputBuffer; | |||
909 | { | |||
910 | llvm::BitstreamWriter OutputStream(OutputBuffer); | |||
911 | if (Builder.writeIndex(OutputStream)) | |||
912 | return llvm::createStringError(std::errc::io_error, | |||
913 | "failed writing index"); | |||
914 | } | |||
915 | ||||
916 | return llvm::writeFileAtomically( | |||
917 | (IndexPath + "-%%%%%%%%").str(), IndexPath, | |||
918 | llvm::StringRef(OutputBuffer.data(), OutputBuffer.size())); | |||
919 | } | |||
920 | ||||
921 | namespace { | |||
922 | class GlobalIndexIdentifierIterator : public IdentifierIterator { | |||
923 | /// The current position within the identifier lookup table. | |||
924 | IdentifierIndexTable::key_iterator Current; | |||
925 | ||||
926 | /// The end position within the identifier lookup table. | |||
927 | IdentifierIndexTable::key_iterator End; | |||
928 | ||||
929 | public: | |||
930 | explicit GlobalIndexIdentifierIterator(IdentifierIndexTable &Idx) { | |||
931 | Current = Idx.key_begin(); | |||
932 | End = Idx.key_end(); | |||
933 | } | |||
934 | ||||
935 | StringRef Next() override { | |||
936 | if (Current == End) | |||
937 | return StringRef(); | |||
938 | ||||
939 | StringRef Result = *Current; | |||
940 | ++Current; | |||
941 | return Result; | |||
942 | } | |||
943 | }; | |||
944 | } | |||
945 | ||||
946 | IdentifierIterator *GlobalModuleIndex::createIdentifierIterator() const { | |||
947 | IdentifierIndexTable &Table = | |||
948 | *static_cast<IdentifierIndexTable *>(IdentifierIndex); | |||
949 | return new GlobalIndexIdentifierIterator(Table); | |||
950 | } |
1 | //===- BitstreamReader.h - Low-level bitstream reader interface -*- 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 header defines the BitstreamReader class. This class can be used to | ||||||
10 | // read an arbitrary bitstream, regardless of its contents. | ||||||
11 | // | ||||||
12 | //===----------------------------------------------------------------------===// | ||||||
13 | |||||||
14 | #ifndef LLVM_BITSTREAM_BITSTREAMREADER_H | ||||||
15 | #define LLVM_BITSTREAM_BITSTREAMREADER_H | ||||||
16 | |||||||
17 | #include "llvm/ADT/ArrayRef.h" | ||||||
18 | #include "llvm/ADT/SmallVector.h" | ||||||
19 | #include "llvm/Bitstream/BitCodes.h" | ||||||
20 | #include "llvm/Support/Endian.h" | ||||||
21 | #include "llvm/Support/ErrorHandling.h" | ||||||
22 | #include "llvm/Support/MathExtras.h" | ||||||
23 | #include "llvm/Support/MemoryBuffer.h" | ||||||
24 | #include <algorithm> | ||||||
25 | #include <cassert> | ||||||
26 | #include <climits> | ||||||
27 | #include <cstddef> | ||||||
28 | #include <cstdint> | ||||||
29 | #include <memory> | ||||||
30 | #include <string> | ||||||
31 | #include <utility> | ||||||
32 | #include <vector> | ||||||
33 | |||||||
34 | namespace llvm { | ||||||
35 | |||||||
36 | /// This class maintains the abbreviations read from a block info block. | ||||||
37 | class BitstreamBlockInfo { | ||||||
38 | public: | ||||||
39 | /// This contains information emitted to BLOCKINFO_BLOCK blocks. These | ||||||
40 | /// describe abbreviations that all blocks of the specified ID inherit. | ||||||
41 | struct BlockInfo { | ||||||
42 | unsigned BlockID = 0; | ||||||
43 | std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs; | ||||||
44 | std::string Name; | ||||||
45 | std::vector<std::pair<unsigned, std::string>> RecordNames; | ||||||
46 | }; | ||||||
47 | |||||||
48 | private: | ||||||
49 | std::vector<BlockInfo> BlockInfoRecords; | ||||||
50 | |||||||
51 | public: | ||||||
52 | /// If there is block info for the specified ID, return it, otherwise return | ||||||
53 | /// null. | ||||||
54 | const BlockInfo *getBlockInfo(unsigned BlockID) const { | ||||||
55 | // Common case, the most recent entry matches BlockID. | ||||||
56 | if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID) | ||||||
57 | return &BlockInfoRecords.back(); | ||||||
58 | |||||||
59 | for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size()); | ||||||
60 | i != e; ++i) | ||||||
61 | if (BlockInfoRecords[i].BlockID == BlockID) | ||||||
62 | return &BlockInfoRecords[i]; | ||||||
63 | return nullptr; | ||||||
64 | } | ||||||
65 | |||||||
66 | BlockInfo &getOrCreateBlockInfo(unsigned BlockID) { | ||||||
67 | if (const BlockInfo *BI = getBlockInfo(BlockID)) | ||||||
68 | return *const_cast<BlockInfo*>(BI); | ||||||
69 | |||||||
70 | // Otherwise, add a new record. | ||||||
71 | BlockInfoRecords.emplace_back(); | ||||||
72 | BlockInfoRecords.back().BlockID = BlockID; | ||||||
73 | return BlockInfoRecords.back(); | ||||||
74 | } | ||||||
75 | }; | ||||||
76 | |||||||
77 | /// This represents a position within a bitstream. There may be multiple | ||||||
78 | /// independent cursors reading within one bitstream, each maintaining their | ||||||
79 | /// own local state. | ||||||
80 | class SimpleBitstreamCursor { | ||||||
81 | ArrayRef<uint8_t> BitcodeBytes; | ||||||
82 | size_t NextChar = 0; | ||||||
83 | |||||||
84 | public: | ||||||
85 | /// This is the current data we have pulled from the stream but have not | ||||||
86 | /// returned to the client. This is specifically and intentionally defined to | ||||||
87 | /// follow the word size of the host machine for efficiency. We use word_t in | ||||||
88 | /// places that are aware of this to make it perfectly explicit what is going | ||||||
89 | /// on. | ||||||
90 | using word_t = size_t; | ||||||
91 | |||||||
92 | private: | ||||||
93 | word_t CurWord = 0; | ||||||
94 | |||||||
95 | /// This is the number of bits in CurWord that are valid. This is always from | ||||||
96 | /// [0...bits_of(size_t)-1] inclusive. | ||||||
97 | unsigned BitsInCurWord = 0; | ||||||
98 | |||||||
99 | public: | ||||||
100 | static const constexpr size_t MaxChunkSize = sizeof(word_t) * 8; | ||||||
101 | |||||||
102 | SimpleBitstreamCursor() = default; | ||||||
103 | explicit SimpleBitstreamCursor(ArrayRef<uint8_t> BitcodeBytes) | ||||||
104 | : BitcodeBytes(BitcodeBytes) {} | ||||||
105 | explicit SimpleBitstreamCursor(StringRef BitcodeBytes) | ||||||
106 | : BitcodeBytes(arrayRefFromStringRef(BitcodeBytes)) {} | ||||||
107 | explicit SimpleBitstreamCursor(MemoryBufferRef BitcodeBytes) | ||||||
108 | : SimpleBitstreamCursor(BitcodeBytes.getBuffer()) {} | ||||||
109 | |||||||
110 | bool canSkipToPos(size_t pos) const { | ||||||
111 | // pos can be skipped to if it is a valid address or one byte past the end. | ||||||
112 | return pos <= BitcodeBytes.size(); | ||||||
113 | } | ||||||
114 | |||||||
115 | bool AtEndOfStream() { | ||||||
116 | return BitsInCurWord == 0 && BitcodeBytes.size() <= NextChar; | ||||||
117 | } | ||||||
118 | |||||||
119 | /// Return the bit # of the bit we are reading. | ||||||
120 | uint64_t GetCurrentBitNo() const { | ||||||
121 | return NextChar*CHAR_BIT8 - BitsInCurWord; | ||||||
122 | } | ||||||
123 | |||||||
124 | // Return the byte # of the current bit. | ||||||
125 | uint64_t getCurrentByteNo() const { return GetCurrentBitNo() / 8; } | ||||||
126 | |||||||
127 | ArrayRef<uint8_t> getBitcodeBytes() const { return BitcodeBytes; } | ||||||
128 | |||||||
129 | /// Reset the stream to the specified bit number. | ||||||
130 | Error JumpToBit(uint64_t BitNo) { | ||||||
131 | size_t ByteNo = size_t(BitNo/8) & ~(sizeof(word_t)-1); | ||||||
132 | unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1)); | ||||||
133 | assert(canSkipToPos(ByteNo) && "Invalid location")((canSkipToPos(ByteNo) && "Invalid location") ? static_cast <void> (0) : __assert_fail ("canSkipToPos(ByteNo) && \"Invalid location\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Bitstream/BitstreamReader.h" , 133, __PRETTY_FUNCTION__)); | ||||||
134 | |||||||
135 | // Move the cursor to the right word. | ||||||
136 | NextChar = ByteNo; | ||||||
137 | BitsInCurWord = 0; | ||||||
138 | |||||||
139 | // Skip over any bits that are already consumed. | ||||||
140 | if (WordBitNo) { | ||||||
141 | if (Expected<word_t> Res = Read(WordBitNo)) | ||||||
142 | return Error::success(); | ||||||
143 | else | ||||||
144 | return Res.takeError(); | ||||||
145 | } | ||||||
146 | |||||||
147 | return Error::success(); | ||||||
148 | } | ||||||
149 | |||||||
150 | /// Get a pointer into the bitstream at the specified byte offset. | ||||||
151 | const uint8_t *getPointerToByte(uint64_t ByteNo, uint64_t NumBytes) { | ||||||
152 | return BitcodeBytes.data() + ByteNo; | ||||||
153 | } | ||||||
154 | |||||||
155 | /// Get a pointer into the bitstream at the specified bit offset. | ||||||
156 | /// | ||||||
157 | /// The bit offset must be on a byte boundary. | ||||||
158 | const uint8_t *getPointerToBit(uint64_t BitNo, uint64_t NumBytes) { | ||||||
159 | assert(!(BitNo % 8) && "Expected bit on byte boundary")((!(BitNo % 8) && "Expected bit on byte boundary") ? static_cast <void> (0) : __assert_fail ("!(BitNo % 8) && \"Expected bit on byte boundary\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Bitstream/BitstreamReader.h" , 159, __PRETTY_FUNCTION__)); | ||||||
160 | return getPointerToByte(BitNo / 8, NumBytes); | ||||||
161 | } | ||||||
162 | |||||||
163 | Error fillCurWord() { | ||||||
164 | if (NextChar >= BitcodeBytes.size()) | ||||||
165 | return createStringError(std::errc::io_error, | ||||||
166 | "Unexpected end of file reading %u of %u bytes", | ||||||
167 | NextChar, BitcodeBytes.size()); | ||||||
168 | |||||||
169 | // Read the next word from the stream. | ||||||
170 | const uint8_t *NextCharPtr = BitcodeBytes.data() + NextChar; | ||||||
171 | unsigned BytesRead; | ||||||
172 | if (BitcodeBytes.size() >= NextChar + sizeof(word_t)) { | ||||||
173 | BytesRead = sizeof(word_t); | ||||||
174 | CurWord = | ||||||
175 | support::endian::read<word_t, support::little, support::unaligned>( | ||||||
176 | NextCharPtr); | ||||||
177 | } else { | ||||||
178 | // Short read. | ||||||
179 | BytesRead = BitcodeBytes.size() - NextChar; | ||||||
180 | CurWord = 0; | ||||||
181 | for (unsigned B = 0; B != BytesRead; ++B) | ||||||
182 | CurWord |= uint64_t(NextCharPtr[B]) << (B * 8); | ||||||
183 | } | ||||||
184 | NextChar += BytesRead; | ||||||
185 | BitsInCurWord = BytesRead * 8; | ||||||
186 | return Error::success(); | ||||||
187 | } | ||||||
188 | |||||||
189 | Expected<word_t> Read(unsigned NumBits) { | ||||||
190 | static const unsigned BitsInWord = MaxChunkSize; | ||||||
191 | |||||||
192 | assert(NumBits && NumBits <= BitsInWord &&((NumBits && NumBits <= BitsInWord && "Cannot return zero or more than BitsInWord bits!" ) ? static_cast<void> (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Bitstream/BitstreamReader.h" , 193, __PRETTY_FUNCTION__)) | ||||||
193 | "Cannot return zero or more than BitsInWord bits!")((NumBits && NumBits <= BitsInWord && "Cannot return zero or more than BitsInWord bits!" ) ? static_cast<void> (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Bitstream/BitstreamReader.h" , 193, __PRETTY_FUNCTION__)); | ||||||
194 | |||||||
195 | static const unsigned Mask = sizeof(word_t) > 4 ? 0x3f : 0x1f; | ||||||
196 | |||||||
197 | // If the field is fully contained by CurWord, return it quickly. | ||||||
198 | if (BitsInCurWord >= NumBits) { | ||||||
199 | word_t R = CurWord & (~word_t(0) >> (BitsInWord - NumBits)); | ||||||
200 | |||||||
201 | // Use a mask to avoid undefined behavior. | ||||||
202 | CurWord >>= (NumBits & Mask); | ||||||
203 | |||||||
204 | BitsInCurWord -= NumBits; | ||||||
205 | return R; | ||||||
206 | } | ||||||
207 | |||||||
208 | word_t R = BitsInCurWord
| ||||||
209 | unsigned BitsLeft = NumBits - BitsInCurWord; | ||||||
210 | |||||||
211 | if (Error fillResult = fillCurWord()) | ||||||
212 | return std::move(fillResult); | ||||||
213 | |||||||
214 | // If we run out of data, abort. | ||||||
215 | if (BitsLeft > BitsInCurWord) | ||||||
216 | return createStringError(std::errc::io_error, | ||||||
217 | "Unexpected end of file reading %u of %u bits", | ||||||
218 | BitsInCurWord, BitsLeft); | ||||||
219 | |||||||
220 | word_t R2 = CurWord & (~word_t(0) >> (BitsInWord - BitsLeft)); | ||||||
| |||||||
221 | |||||||
222 | // Use a mask to avoid undefined behavior. | ||||||
223 | CurWord >>= (BitsLeft & Mask); | ||||||
224 | |||||||
225 | BitsInCurWord -= BitsLeft; | ||||||
226 | |||||||
227 | R |= R2 << (NumBits - BitsLeft); | ||||||
228 | |||||||
229 | return R; | ||||||
230 | } | ||||||
231 | |||||||
232 | Expected<uint32_t> ReadVBR(unsigned NumBits) { | ||||||
233 | Expected<unsigned> MaybeRead = Read(NumBits); | ||||||
234 | if (!MaybeRead) | ||||||
235 | return MaybeRead; | ||||||
236 | uint32_t Piece = MaybeRead.get(); | ||||||
237 | |||||||
238 | if ((Piece & (1U << (NumBits-1))) == 0) | ||||||
239 | return Piece; | ||||||
240 | |||||||
241 | uint32_t Result = 0; | ||||||
242 | unsigned NextBit = 0; | ||||||
243 | while (true) { | ||||||
244 | Result |= (Piece & ((1U << (NumBits-1))-1)) << NextBit; | ||||||
245 | |||||||
246 | if ((Piece & (1U << (NumBits-1))) == 0) | ||||||
247 | return Result; | ||||||
248 | |||||||
249 | NextBit += NumBits-1; | ||||||
250 | MaybeRead = Read(NumBits); | ||||||
251 | if (!MaybeRead) | ||||||
252 | return MaybeRead; | ||||||
253 | Piece = MaybeRead.get(); | ||||||
254 | } | ||||||
255 | } | ||||||
256 | |||||||
257 | // Read a VBR that may have a value up to 64-bits in size. The chunk size of | ||||||
258 | // the VBR must still be <= 32 bits though. | ||||||
259 | Expected<uint64_t> ReadVBR64(unsigned NumBits) { | ||||||
260 | Expected<uint64_t> MaybeRead = Read(NumBits); | ||||||
261 | if (!MaybeRead) | ||||||
262 | return MaybeRead; | ||||||
263 | uint32_t Piece = MaybeRead.get(); | ||||||
264 | |||||||
265 | if ((Piece & (1U << (NumBits-1))) == 0) | ||||||
266 | return uint64_t(Piece); | ||||||
267 | |||||||
268 | uint64_t Result = 0; | ||||||
269 | unsigned NextBit = 0; | ||||||
270 | while (true) { | ||||||
271 | Result |= uint64_t(Piece & ((1U << (NumBits-1))-1)) << NextBit; | ||||||
272 | |||||||
273 | if ((Piece & (1U << (NumBits-1))) == 0) | ||||||
274 | return Result; | ||||||
275 | |||||||
276 | NextBit += NumBits-1; | ||||||
277 | MaybeRead = Read(NumBits); | ||||||
278 | if (!MaybeRead) | ||||||
279 | return MaybeRead; | ||||||
280 | Piece = MaybeRead.get(); | ||||||
281 | } | ||||||
282 | } | ||||||
283 | |||||||
284 | void SkipToFourByteBoundary() { | ||||||
285 | // If word_t is 64-bits and if we've read less than 32 bits, just dump | ||||||
286 | // the bits we have up to the next 32-bit boundary. | ||||||
287 | if (sizeof(word_t) > 4 && | ||||||
288 | BitsInCurWord >= 32) { | ||||||
289 | CurWord >>= BitsInCurWord-32; | ||||||
290 | BitsInCurWord = 32; | ||||||
291 | return; | ||||||
292 | } | ||||||
293 | |||||||
294 | BitsInCurWord = 0; | ||||||
295 | } | ||||||
296 | |||||||
297 | /// Return the size of the stream in bytes. | ||||||
298 | size_t SizeInBytes() const { return BitcodeBytes.size(); } | ||||||
299 | |||||||
300 | /// Skip to the end of the file. | ||||||
301 | void skipToEnd() { NextChar = BitcodeBytes.size(); } | ||||||
302 | }; | ||||||
303 | |||||||
304 | /// When advancing through a bitstream cursor, each advance can discover a few | ||||||
305 | /// different kinds of entries: | ||||||
306 | struct BitstreamEntry { | ||||||
307 | enum { | ||||||
308 | Error, // Malformed bitcode was found. | ||||||
309 | EndBlock, // We've reached the end of the current block, (or the end of the | ||||||
310 | // file, which is treated like a series of EndBlock records. | ||||||
311 | SubBlock, // This is the start of a new subblock of a specific ID. | ||||||
312 | Record // This is a record with a specific AbbrevID. | ||||||
313 | } Kind; | ||||||
314 | |||||||
315 | unsigned ID; | ||||||
316 | |||||||
317 | static BitstreamEntry getError() { | ||||||
318 | BitstreamEntry E; E.Kind = Error; return E; | ||||||
319 | } | ||||||
320 | |||||||
321 | static BitstreamEntry getEndBlock() { | ||||||
322 | BitstreamEntry E; E.Kind = EndBlock; return E; | ||||||
323 | } | ||||||
324 | |||||||
325 | static BitstreamEntry getSubBlock(unsigned ID) { | ||||||
326 | BitstreamEntry E; E.Kind = SubBlock; E.ID = ID; return E; | ||||||
327 | } | ||||||
328 | |||||||
329 | static BitstreamEntry getRecord(unsigned AbbrevID) { | ||||||
330 | BitstreamEntry E; E.Kind = Record; E.ID = AbbrevID; return E; | ||||||
331 | } | ||||||
332 | }; | ||||||
333 | |||||||
334 | /// This represents a position within a bitcode file, implemented on top of a | ||||||
335 | /// SimpleBitstreamCursor. | ||||||
336 | /// | ||||||
337 | /// Unlike iterators, BitstreamCursors are heavy-weight objects that should not | ||||||
338 | /// be passed by value. | ||||||
339 | class BitstreamCursor : SimpleBitstreamCursor { | ||||||
340 | // This is the declared size of code values used for the current block, in | ||||||
341 | // bits. | ||||||
342 | unsigned CurCodeSize = 2; | ||||||
343 | |||||||
344 | /// Abbrevs installed at in this block. | ||||||
345 | std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs; | ||||||
346 | |||||||
347 | struct Block { | ||||||
348 | unsigned PrevCodeSize; | ||||||
349 | std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs; | ||||||
350 | |||||||
351 | explicit Block(unsigned PCS) : PrevCodeSize(PCS) {} | ||||||
352 | }; | ||||||
353 | |||||||
354 | /// This tracks the codesize of parent blocks. | ||||||
355 | SmallVector<Block, 8> BlockScope; | ||||||
356 | |||||||
357 | BitstreamBlockInfo *BlockInfo = nullptr; | ||||||
358 | |||||||
359 | public: | ||||||
360 | static const size_t MaxChunkSize = sizeof(word_t) * 8; | ||||||
361 | |||||||
362 | BitstreamCursor() = default; | ||||||
363 | explicit BitstreamCursor(ArrayRef<uint8_t> BitcodeBytes) | ||||||
364 | : SimpleBitstreamCursor(BitcodeBytes) {} | ||||||
365 | explicit BitstreamCursor(StringRef BitcodeBytes) | ||||||
366 | : SimpleBitstreamCursor(BitcodeBytes) {} | ||||||
367 | explicit BitstreamCursor(MemoryBufferRef BitcodeBytes) | ||||||
368 | : SimpleBitstreamCursor(BitcodeBytes) {} | ||||||
369 | |||||||
370 | using SimpleBitstreamCursor::AtEndOfStream; | ||||||
371 | using SimpleBitstreamCursor::canSkipToPos; | ||||||
372 | using SimpleBitstreamCursor::fillCurWord; | ||||||
373 | using SimpleBitstreamCursor::getBitcodeBytes; | ||||||
374 | using SimpleBitstreamCursor::GetCurrentBitNo; | ||||||
375 | using SimpleBitstreamCursor::getCurrentByteNo; | ||||||
376 | using SimpleBitstreamCursor::getPointerToByte; | ||||||
377 | using SimpleBitstreamCursor::JumpToBit; | ||||||
378 | using SimpleBitstreamCursor::Read; | ||||||
379 | using SimpleBitstreamCursor::ReadVBR; | ||||||
380 | using SimpleBitstreamCursor::ReadVBR64; | ||||||
381 | using SimpleBitstreamCursor::SizeInBytes; | ||||||
382 | using SimpleBitstreamCursor::skipToEnd; | ||||||
383 | |||||||
384 | /// Return the number of bits used to encode an abbrev #. | ||||||
385 | unsigned getAbbrevIDWidth() const { return CurCodeSize; } | ||||||
386 | |||||||
387 | /// Flags that modify the behavior of advance(). | ||||||
388 | enum { | ||||||
389 | /// If this flag is used, the advance() method does not automatically pop | ||||||
390 | /// the block scope when the end of a block is reached. | ||||||
391 | AF_DontPopBlockAtEnd = 1, | ||||||
392 | |||||||
393 | /// If this flag is used, abbrev entries are returned just like normal | ||||||
394 | /// records. | ||||||
395 | AF_DontAutoprocessAbbrevs = 2 | ||||||
396 | }; | ||||||
397 | |||||||
398 | /// Advance the current bitstream, returning the next entry in the stream. | ||||||
399 | Expected<BitstreamEntry> advance(unsigned Flags = 0) { | ||||||
400 | while (true) { | ||||||
401 | if (AtEndOfStream()) | ||||||
402 | return BitstreamEntry::getError(); | ||||||
403 | |||||||
404 | Expected<unsigned> MaybeCode = ReadCode(); | ||||||
405 | if (!MaybeCode) | ||||||
406 | return MaybeCode.takeError(); | ||||||
407 | unsigned Code = MaybeCode.get(); | ||||||
408 | |||||||
409 | if (Code == bitc::END_BLOCK) { | ||||||
410 | // Pop the end of the block unless Flags tells us not to. | ||||||
411 | if (!(Flags & AF_DontPopBlockAtEnd) && ReadBlockEnd()) | ||||||
412 | return BitstreamEntry::getError(); | ||||||
413 | return BitstreamEntry::getEndBlock(); | ||||||
414 | } | ||||||
415 | |||||||
416 | if (Code == bitc::ENTER_SUBBLOCK) { | ||||||
417 | if (Expected<unsigned> MaybeSubBlock = ReadSubBlockID()) | ||||||
418 | return BitstreamEntry::getSubBlock(MaybeSubBlock.get()); | ||||||
419 | else | ||||||
420 | return MaybeSubBlock.takeError(); | ||||||
421 | } | ||||||
422 | |||||||
423 | if (Code == bitc::DEFINE_ABBREV && | ||||||
424 | !(Flags & AF_DontAutoprocessAbbrevs)) { | ||||||
425 | // We read and accumulate abbrev's, the client can't do anything with | ||||||
426 | // them anyway. | ||||||
427 | if (Error Err = ReadAbbrevRecord()) | ||||||
428 | return std::move(Err); | ||||||
429 | continue; | ||||||
430 | } | ||||||
431 | |||||||
432 | return BitstreamEntry::getRecord(Code); | ||||||
433 | } | ||||||
434 | } | ||||||
435 | |||||||
436 | /// This is a convenience function for clients that don't expect any | ||||||
437 | /// subblocks. This just skips over them automatically. | ||||||
438 | Expected<BitstreamEntry> advanceSkippingSubblocks(unsigned Flags = 0) { | ||||||
439 | while (true) { | ||||||
440 | // If we found a normal entry, return it. | ||||||
441 | Expected<BitstreamEntry> MaybeEntry = advance(Flags); | ||||||
442 | if (!MaybeEntry) | ||||||
443 | return MaybeEntry; | ||||||
444 | BitstreamEntry Entry = MaybeEntry.get(); | ||||||
445 | |||||||
446 | if (Entry.Kind != BitstreamEntry::SubBlock) | ||||||
447 | return Entry; | ||||||
448 | |||||||
449 | // If we found a sub-block, just skip over it and check the next entry. | ||||||
450 | if (Error Err = SkipBlock()) | ||||||
451 | return std::move(Err); | ||||||
452 | } | ||||||
453 | } | ||||||
454 | |||||||
455 | Expected<unsigned> ReadCode() { return Read(CurCodeSize); } | ||||||
456 | |||||||
457 | // Block header: | ||||||
458 | // [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen] | ||||||
459 | |||||||
460 | /// Having read the ENTER_SUBBLOCK code, read the BlockID for the block. | ||||||
461 | Expected<unsigned> ReadSubBlockID() { return ReadVBR(bitc::BlockIDWidth); } | ||||||
462 | |||||||
463 | /// Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body | ||||||
464 | /// of this block. | ||||||
465 | Error SkipBlock() { | ||||||
466 | // Read and ignore the codelen value. | ||||||
467 | if (Expected<uint32_t> Res = ReadVBR(bitc::CodeLenWidth)) | ||||||
468 | ; // Since we are skipping this block, we don't care what code widths are | ||||||
469 | // used inside of it. | ||||||
470 | else | ||||||
471 | return Res.takeError(); | ||||||
472 | |||||||
473 | SkipToFourByteBoundary(); | ||||||
474 | Expected<unsigned> MaybeNum = Read(bitc::BlockSizeWidth); | ||||||
475 | if (!MaybeNum) | ||||||
476 | return MaybeNum.takeError(); | ||||||
477 | size_t NumFourBytes = MaybeNum.get(); | ||||||
478 | |||||||
479 | // Check that the block wasn't partially defined, and that the offset isn't | ||||||
480 | // bogus. | ||||||
481 | size_t SkipTo = GetCurrentBitNo() + NumFourBytes * 4 * 8; | ||||||
482 | if (AtEndOfStream()) | ||||||
483 | return createStringError(std::errc::illegal_byte_sequence, | ||||||
484 | "can't skip block: already at end of stream"); | ||||||
485 | if (!canSkipToPos(SkipTo / 8)) | ||||||
486 | return createStringError(std::errc::illegal_byte_sequence, | ||||||
487 | "can't skip to bit %zu from %" PRIu64"l" "u", SkipTo, | ||||||
488 | GetCurrentBitNo()); | ||||||
489 | |||||||
490 | if (Error Res = JumpToBit(SkipTo)) | ||||||
491 | return Res; | ||||||
492 | |||||||
493 | return Error::success(); | ||||||
494 | } | ||||||
495 | |||||||
496 | /// Having read the ENTER_SUBBLOCK abbrevid, and enter the block. | ||||||
497 | Error EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = nullptr); | ||||||
498 | |||||||
499 | bool ReadBlockEnd() { | ||||||
500 | if (BlockScope.empty()) return true; | ||||||
501 | |||||||
502 | // Block tail: | ||||||
503 | // [END_BLOCK, <align4bytes>] | ||||||
504 | SkipToFourByteBoundary(); | ||||||
505 | |||||||
506 | popBlockScope(); | ||||||
507 | return false; | ||||||
508 | } | ||||||
509 | |||||||
510 | private: | ||||||
511 | void popBlockScope() { | ||||||
512 | CurCodeSize = BlockScope.back().PrevCodeSize; | ||||||
513 | |||||||
514 | CurAbbrevs = std::move(BlockScope.back().PrevAbbrevs); | ||||||
515 | BlockScope.pop_back(); | ||||||
516 | } | ||||||
517 | |||||||
518 | //===--------------------------------------------------------------------===// | ||||||
519 | // Record Processing | ||||||
520 | //===--------------------------------------------------------------------===// | ||||||
521 | |||||||
522 | public: | ||||||
523 | /// Return the abbreviation for the specified AbbrevId. | ||||||
524 | const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) { | ||||||
525 | unsigned AbbrevNo = AbbrevID - bitc::FIRST_APPLICATION_ABBREV; | ||||||
526 | if (AbbrevNo >= CurAbbrevs.size()) | ||||||
527 | report_fatal_error("Invalid abbrev number"); | ||||||
528 | return CurAbbrevs[AbbrevNo].get(); | ||||||
529 | } | ||||||
530 | |||||||
531 | /// Read the current record and discard it, returning the code for the record. | ||||||
532 | Expected<unsigned> skipRecord(unsigned AbbrevID); | ||||||
533 | |||||||
534 | Expected<unsigned> readRecord(unsigned AbbrevID, | ||||||
535 | SmallVectorImpl<uint64_t> &Vals, | ||||||
536 | StringRef *Blob = nullptr); | ||||||
537 | |||||||
538 | //===--------------------------------------------------------------------===// | ||||||
539 | // Abbrev Processing | ||||||
540 | //===--------------------------------------------------------------------===// | ||||||
541 | Error ReadAbbrevRecord(); | ||||||
542 | |||||||
543 | /// Read and return a block info block from the bitstream. If an error was | ||||||
544 | /// encountered, return None. | ||||||
545 | /// | ||||||
546 | /// \param ReadBlockInfoNames Whether to read block/record name information in | ||||||
547 | /// the BlockInfo block. Only llvm-bcanalyzer uses this. | ||||||
548 | Expected<Optional<BitstreamBlockInfo>> | ||||||
549 | ReadBlockInfoBlock(bool ReadBlockInfoNames = false); | ||||||
550 | |||||||
551 | /// Set the block info to be used by this BitstreamCursor to interpret | ||||||
552 | /// abbreviated records. | ||||||
553 | void setBlockInfo(BitstreamBlockInfo *BI) { BlockInfo = BI; } | ||||||
554 | }; | ||||||
555 | |||||||
556 | } // end llvm namespace | ||||||
557 | |||||||
558 | #endif // LLVM_BITSTREAM_BITSTREAMREADER_H |
1 | //===- llvm/Support/Error.h - Recoverable error handling --------*- 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 defines an API used to report recoverable errors. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_SUPPORT_ERROR_H |
14 | #define LLVM_SUPPORT_ERROR_H |
15 | |
16 | #include "llvm-c/Error.h" |
17 | #include "llvm/ADT/STLExtras.h" |
18 | #include "llvm/ADT/SmallVector.h" |
19 | #include "llvm/ADT/StringExtras.h" |
20 | #include "llvm/ADT/Twine.h" |
21 | #include "llvm/Config/abi-breaking.h" |
22 | #include "llvm/Support/AlignOf.h" |
23 | #include "llvm/Support/Compiler.h" |
24 | #include "llvm/Support/Debug.h" |
25 | #include "llvm/Support/ErrorHandling.h" |
26 | #include "llvm/Support/ErrorOr.h" |
27 | #include "llvm/Support/Format.h" |
28 | #include "llvm/Support/raw_ostream.h" |
29 | #include <algorithm> |
30 | #include <cassert> |
31 | #include <cstdint> |
32 | #include <cstdlib> |
33 | #include <functional> |
34 | #include <memory> |
35 | #include <new> |
36 | #include <string> |
37 | #include <system_error> |
38 | #include <type_traits> |
39 | #include <utility> |
40 | #include <vector> |
41 | |
42 | namespace llvm { |
43 | |
44 | class ErrorSuccess; |
45 | |
46 | /// Base class for error info classes. Do not extend this directly: Extend |
47 | /// the ErrorInfo template subclass instead. |
48 | class ErrorInfoBase { |
49 | public: |
50 | virtual ~ErrorInfoBase() = default; |
51 | |
52 | /// Print an error message to an output stream. |
53 | virtual void log(raw_ostream &OS) const = 0; |
54 | |
55 | /// Return the error message as a string. |
56 | virtual std::string message() const { |
57 | std::string Msg; |
58 | raw_string_ostream OS(Msg); |
59 | log(OS); |
60 | return OS.str(); |
61 | } |
62 | |
63 | /// Convert this error to a std::error_code. |
64 | /// |
65 | /// This is a temporary crutch to enable interaction with code still |
66 | /// using std::error_code. It will be removed in the future. |
67 | virtual std::error_code convertToErrorCode() const = 0; |
68 | |
69 | // Returns the class ID for this type. |
70 | static const void *classID() { return &ID; } |
71 | |
72 | // Returns the class ID for the dynamic type of this ErrorInfoBase instance. |
73 | virtual const void *dynamicClassID() const = 0; |
74 | |
75 | // Check whether this instance is a subclass of the class identified by |
76 | // ClassID. |
77 | virtual bool isA(const void *const ClassID) const { |
78 | return ClassID == classID(); |
79 | } |
80 | |
81 | // Check whether this instance is a subclass of ErrorInfoT. |
82 | template <typename ErrorInfoT> bool isA() const { |
83 | return isA(ErrorInfoT::classID()); |
84 | } |
85 | |
86 | private: |
87 | virtual void anchor(); |
88 | |
89 | static char ID; |
90 | }; |
91 | |
92 | /// Lightweight error class with error context and mandatory checking. |
93 | /// |
94 | /// Instances of this class wrap a ErrorInfoBase pointer. Failure states |
95 | /// are represented by setting the pointer to a ErrorInfoBase subclass |
96 | /// instance containing information describing the failure. Success is |
97 | /// represented by a null pointer value. |
98 | /// |
99 | /// Instances of Error also contains a 'Checked' flag, which must be set |
100 | /// before the destructor is called, otherwise the destructor will trigger a |
101 | /// runtime error. This enforces at runtime the requirement that all Error |
102 | /// instances be checked or returned to the caller. |
103 | /// |
104 | /// There are two ways to set the checked flag, depending on what state the |
105 | /// Error instance is in. For Error instances indicating success, it |
106 | /// is sufficient to invoke the boolean conversion operator. E.g.: |
107 | /// |
108 | /// @code{.cpp} |
109 | /// Error foo(<...>); |
110 | /// |
111 | /// if (auto E = foo(<...>)) |
112 | /// return E; // <- Return E if it is in the error state. |
113 | /// // We have verified that E was in the success state. It can now be safely |
114 | /// // destroyed. |
115 | /// @endcode |
116 | /// |
117 | /// A success value *can not* be dropped. For example, just calling 'foo(<...>)' |
118 | /// without testing the return value will raise a runtime error, even if foo |
119 | /// returns success. |
120 | /// |
121 | /// For Error instances representing failure, you must use either the |
122 | /// handleErrors or handleAllErrors function with a typed handler. E.g.: |
123 | /// |
124 | /// @code{.cpp} |
125 | /// class MyErrorInfo : public ErrorInfo<MyErrorInfo> { |
126 | /// // Custom error info. |
127 | /// }; |
128 | /// |
129 | /// Error foo(<...>) { return make_error<MyErrorInfo>(...); } |
130 | /// |
131 | /// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo. |
132 | /// auto NewE = |
133 | /// handleErrors(E, |
134 | /// [](const MyErrorInfo &M) { |
135 | /// // Deal with the error. |
136 | /// }, |
137 | /// [](std::unique_ptr<OtherError> M) -> Error { |
138 | /// if (canHandle(*M)) { |
139 | /// // handle error. |
140 | /// return Error::success(); |
141 | /// } |
142 | /// // Couldn't handle this error instance. Pass it up the stack. |
143 | /// return Error(std::move(M)); |
144 | /// ); |
145 | /// // Note - we must check or return NewE in case any of the handlers |
146 | /// // returned a new error. |
147 | /// @endcode |
148 | /// |
149 | /// The handleAllErrors function is identical to handleErrors, except |
150 | /// that it has a void return type, and requires all errors to be handled and |
151 | /// no new errors be returned. It prevents errors (assuming they can all be |
152 | /// handled) from having to be bubbled all the way to the top-level. |
153 | /// |
154 | /// *All* Error instances must be checked before destruction, even if |
155 | /// they're moved-assigned or constructed from Success values that have already |
156 | /// been checked. This enforces checking through all levels of the call stack. |
157 | class LLVM_NODISCARD[[clang::warn_unused_result]] Error { |
158 | // Both ErrorList and FileError need to be able to yank ErrorInfoBase |
159 | // pointers out of this class to add to the error list. |
160 | friend class ErrorList; |
161 | friend class FileError; |
162 | |
163 | // handleErrors needs to be able to set the Checked flag. |
164 | template <typename... HandlerTs> |
165 | friend Error handleErrors(Error E, HandlerTs &&... Handlers); |
166 | |
167 | // Expected<T> needs to be able to steal the payload when constructed from an |
168 | // error. |
169 | template <typename T> friend class Expected; |
170 | |
171 | // wrap needs to be able to steal the payload. |
172 | friend LLVMErrorRef wrap(Error); |
173 | |
174 | protected: |
175 | /// Create a success value. Prefer using 'Error::success()' for readability |
176 | Error() { |
177 | setPtr(nullptr); |
178 | setChecked(false); |
179 | } |
180 | |
181 | public: |
182 | /// Create a success value. |
183 | static ErrorSuccess success(); |
184 | |
185 | // Errors are not copy-constructable. |
186 | Error(const Error &Other) = delete; |
187 | |
188 | /// Move-construct an error value. The newly constructed error is considered |
189 | /// unchecked, even if the source error had been checked. The original error |
190 | /// becomes a checked Success value, regardless of its original state. |
191 | Error(Error &&Other) { |
192 | setChecked(true); |
193 | *this = std::move(Other); |
194 | } |
195 | |
196 | /// Create an error value. Prefer using the 'make_error' function, but |
197 | /// this constructor can be useful when "re-throwing" errors from handlers. |
198 | Error(std::unique_ptr<ErrorInfoBase> Payload) { |
199 | setPtr(Payload.release()); |
200 | setChecked(false); |
201 | } |
202 | |
203 | // Errors are not copy-assignable. |
204 | Error &operator=(const Error &Other) = delete; |
205 | |
206 | /// Move-assign an error value. The current error must represent success, you |
207 | /// you cannot overwrite an unhandled error. The current error is then |
208 | /// considered unchecked. The source error becomes a checked success value, |
209 | /// regardless of its original state. |
210 | Error &operator=(Error &&Other) { |
211 | // Don't allow overwriting of unchecked values. |
212 | assertIsChecked(); |
213 | setPtr(Other.getPtr()); |
214 | |
215 | // This Error is unchecked, even if the source error was checked. |
216 | setChecked(false); |
217 | |
218 | // Null out Other's payload and set its checked bit. |
219 | Other.setPtr(nullptr); |
220 | Other.setChecked(true); |
221 | |
222 | return *this; |
223 | } |
224 | |
225 | /// Destroy a Error. Fails with a call to abort() if the error is |
226 | /// unchecked. |
227 | ~Error() { |
228 | assertIsChecked(); |
229 | delete getPtr(); |
230 | } |
231 | |
232 | /// Bool conversion. Returns true if this Error is in a failure state, |
233 | /// and false if it is in an accept state. If the error is in a Success state |
234 | /// it will be considered checked. |
235 | explicit operator bool() { |
236 | setChecked(getPtr() == nullptr); |
237 | return getPtr() != nullptr; |
238 | } |
239 | |
240 | /// Check whether one error is a subclass of another. |
241 | template <typename ErrT> bool isA() const { |
242 | return getPtr() && getPtr()->isA(ErrT::classID()); |
243 | } |
244 | |
245 | /// Returns the dynamic class id of this error, or null if this is a success |
246 | /// value. |
247 | const void* dynamicClassID() const { |
248 | if (!getPtr()) |
249 | return nullptr; |
250 | return getPtr()->dynamicClassID(); |
251 | } |
252 | |
253 | private: |
254 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
255 | // assertIsChecked() happens very frequently, but under normal circumstances |
256 | // is supposed to be a no-op. So we want it to be inlined, but having a bunch |
257 | // of debug prints can cause the function to be too large for inlining. So |
258 | // it's important that we define this function out of line so that it can't be |
259 | // inlined. |
260 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) |
261 | void fatalUncheckedError() const; |
262 | #endif |
263 | |
264 | void assertIsChecked() { |
265 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
266 | if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false)) |
267 | fatalUncheckedError(); |
268 | #endif |
269 | } |
270 | |
271 | ErrorInfoBase *getPtr() const { |
272 | return reinterpret_cast<ErrorInfoBase*>( |
273 | reinterpret_cast<uintptr_t>(Payload) & |
274 | ~static_cast<uintptr_t>(0x1)); |
275 | } |
276 | |
277 | void setPtr(ErrorInfoBase *EI) { |
278 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
279 | Payload = reinterpret_cast<ErrorInfoBase*>( |
280 | (reinterpret_cast<uintptr_t>(EI) & |
281 | ~static_cast<uintptr_t>(0x1)) | |
282 | (reinterpret_cast<uintptr_t>(Payload) & 0x1)); |
283 | #else |
284 | Payload = EI; |
285 | #endif |
286 | } |
287 | |
288 | bool getChecked() const { |
289 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
290 | return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0; |
291 | #else |
292 | return true; |
293 | #endif |
294 | } |
295 | |
296 | void setChecked(bool V) { |
297 | Payload = reinterpret_cast<ErrorInfoBase*>( |
298 | (reinterpret_cast<uintptr_t>(Payload) & |
299 | ~static_cast<uintptr_t>(0x1)) | |
300 | (V ? 0 : 1)); |
301 | } |
302 | |
303 | std::unique_ptr<ErrorInfoBase> takePayload() { |
304 | std::unique_ptr<ErrorInfoBase> Tmp(getPtr()); |
305 | setPtr(nullptr); |
306 | setChecked(true); |
307 | return Tmp; |
308 | } |
309 | |
310 | friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) { |
311 | if (auto P = E.getPtr()) |
312 | P->log(OS); |
313 | else |
314 | OS << "success"; |
315 | return OS; |
316 | } |
317 | |
318 | ErrorInfoBase *Payload = nullptr; |
319 | }; |
320 | |
321 | /// Subclass of Error for the sole purpose of identifying the success path in |
322 | /// the type system. This allows to catch invalid conversion to Expected<T> at |
323 | /// compile time. |
324 | class ErrorSuccess final : public Error {}; |
325 | |
326 | inline ErrorSuccess Error::success() { return ErrorSuccess(); } |
327 | |
328 | /// Make a Error instance representing failure using the given error info |
329 | /// type. |
330 | template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) { |
331 | return Error(std::make_unique<ErrT>(std::forward<ArgTs>(Args)...)); |
332 | } |
333 | |
334 | /// Base class for user error types. Users should declare their error types |
335 | /// like: |
336 | /// |
337 | /// class MyError : public ErrorInfo<MyError> { |
338 | /// .... |
339 | /// }; |
340 | /// |
341 | /// This class provides an implementation of the ErrorInfoBase::kind |
342 | /// method, which is used by the Error RTTI system. |
343 | template <typename ThisErrT, typename ParentErrT = ErrorInfoBase> |
344 | class ErrorInfo : public ParentErrT { |
345 | public: |
346 | using ParentErrT::ParentErrT; // inherit constructors |
347 | |
348 | static const void *classID() { return &ThisErrT::ID; } |
349 | |
350 | const void *dynamicClassID() const override { return &ThisErrT::ID; } |
351 | |
352 | bool isA(const void *const ClassID) const override { |
353 | return ClassID == classID() || ParentErrT::isA(ClassID); |
354 | } |
355 | }; |
356 | |
357 | /// Special ErrorInfo subclass representing a list of ErrorInfos. |
358 | /// Instances of this class are constructed by joinError. |
359 | class ErrorList final : public ErrorInfo<ErrorList> { |
360 | // handleErrors needs to be able to iterate the payload list of an |
361 | // ErrorList. |
362 | template <typename... HandlerTs> |
363 | friend Error handleErrors(Error E, HandlerTs &&... Handlers); |
364 | |
365 | // joinErrors is implemented in terms of join. |
366 | friend Error joinErrors(Error, Error); |
367 | |
368 | public: |
369 | void log(raw_ostream &OS) const override { |
370 | OS << "Multiple errors:\n"; |
371 | for (auto &ErrPayload : Payloads) { |
372 | ErrPayload->log(OS); |
373 | OS << "\n"; |
374 | } |
375 | } |
376 | |
377 | std::error_code convertToErrorCode() const override; |
378 | |
379 | // Used by ErrorInfo::classID. |
380 | static char ID; |
381 | |
382 | private: |
383 | ErrorList(std::unique_ptr<ErrorInfoBase> Payload1, |
384 | std::unique_ptr<ErrorInfoBase> Payload2) { |
385 | assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&((!Payload1->isA<ErrorList>() && !Payload2-> isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors" ) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 386, __PRETTY_FUNCTION__)) |
386 | "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2-> isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors" ) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 386, __PRETTY_FUNCTION__)); |
387 | Payloads.push_back(std::move(Payload1)); |
388 | Payloads.push_back(std::move(Payload2)); |
389 | } |
390 | |
391 | static Error join(Error E1, Error E2) { |
392 | if (!E1) |
393 | return E2; |
394 | if (!E2) |
395 | return E1; |
396 | if (E1.isA<ErrorList>()) { |
397 | auto &E1List = static_cast<ErrorList &>(*E1.getPtr()); |
398 | if (E2.isA<ErrorList>()) { |
399 | auto E2Payload = E2.takePayload(); |
400 | auto &E2List = static_cast<ErrorList &>(*E2Payload); |
401 | for (auto &Payload : E2List.Payloads) |
402 | E1List.Payloads.push_back(std::move(Payload)); |
403 | } else |
404 | E1List.Payloads.push_back(E2.takePayload()); |
405 | |
406 | return E1; |
407 | } |
408 | if (E2.isA<ErrorList>()) { |
409 | auto &E2List = static_cast<ErrorList &>(*E2.getPtr()); |
410 | E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload()); |
411 | return E2; |
412 | } |
413 | return Error(std::unique_ptr<ErrorList>( |
414 | new ErrorList(E1.takePayload(), E2.takePayload()))); |
415 | } |
416 | |
417 | std::vector<std::unique_ptr<ErrorInfoBase>> Payloads; |
418 | }; |
419 | |
420 | /// Concatenate errors. The resulting Error is unchecked, and contains the |
421 | /// ErrorInfo(s), if any, contained in E1, followed by the |
422 | /// ErrorInfo(s), if any, contained in E2. |
423 | inline Error joinErrors(Error E1, Error E2) { |
424 | return ErrorList::join(std::move(E1), std::move(E2)); |
425 | } |
426 | |
427 | /// Tagged union holding either a T or a Error. |
428 | /// |
429 | /// This class parallels ErrorOr, but replaces error_code with Error. Since |
430 | /// Error cannot be copied, this class replaces getError() with |
431 | /// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the |
432 | /// error class type. |
433 | template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected { |
434 | template <class T1> friend class ExpectedAsOutParameter; |
435 | template <class OtherT> friend class Expected; |
436 | |
437 | static const bool isRef = std::is_reference<T>::value; |
438 | |
439 | using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>; |
440 | |
441 | using error_type = std::unique_ptr<ErrorInfoBase>; |
442 | |
443 | public: |
444 | using storage_type = typename std::conditional<isRef, wrap, T>::type; |
445 | using value_type = T; |
446 | |
447 | private: |
448 | using reference = typename std::remove_reference<T>::type &; |
449 | using const_reference = const typename std::remove_reference<T>::type &; |
450 | using pointer = typename std::remove_reference<T>::type *; |
451 | using const_pointer = const typename std::remove_reference<T>::type *; |
452 | |
453 | public: |
454 | /// Create an Expected<T> error value from the given Error. |
455 | Expected(Error Err) |
456 | : HasError(true) |
457 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
458 | // Expected is unchecked upon construction in Debug builds. |
459 | , Unchecked(true) |
460 | #endif |
461 | { |
462 | assert(Err && "Cannot create Expected<T> from Error success value.")((Err && "Cannot create Expected<T> from Error success value." ) ? static_cast<void> (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 462, __PRETTY_FUNCTION__)); |
463 | new (getErrorStorage()) error_type(Err.takePayload()); |
464 | } |
465 | |
466 | /// Forbid to convert from Error::success() implicitly, this avoids having |
467 | /// Expected<T> foo() { return Error::success(); } which compiles otherwise |
468 | /// but triggers the assertion above. |
469 | Expected(ErrorSuccess) = delete; |
470 | |
471 | /// Create an Expected<T> success value from the given OtherT value, which |
472 | /// must be convertible to T. |
473 | template <typename OtherT> |
474 | Expected(OtherT &&Val, |
475 | typename std::enable_if<std::is_convertible<OtherT, T>::value>::type |
476 | * = nullptr) |
477 | : HasError(false) |
478 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
479 | // Expected is unchecked upon construction in Debug builds. |
480 | , Unchecked(true) |
481 | #endif |
482 | { |
483 | new (getStorage()) storage_type(std::forward<OtherT>(Val)); |
484 | } |
485 | |
486 | /// Move construct an Expected<T> value. |
487 | Expected(Expected &&Other) { moveConstruct(std::move(Other)); } |
488 | |
489 | /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT |
490 | /// must be convertible to T. |
491 | template <class OtherT> |
492 | Expected(Expected<OtherT> &&Other, |
493 | typename std::enable_if<std::is_convertible<OtherT, T>::value>::type |
494 | * = nullptr) { |
495 | moveConstruct(std::move(Other)); |
496 | } |
497 | |
498 | /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT |
499 | /// isn't convertible to T. |
500 | template <class OtherT> |
501 | explicit Expected( |
502 | Expected<OtherT> &&Other, |
503 | typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * = |
504 | nullptr) { |
505 | moveConstruct(std::move(Other)); |
506 | } |
507 | |
508 | /// Move-assign from another Expected<T>. |
509 | Expected &operator=(Expected &&Other) { |
510 | moveAssign(std::move(Other)); |
511 | return *this; |
512 | } |
513 | |
514 | /// Destroy an Expected<T>. |
515 | ~Expected() { |
516 | assertIsChecked(); |
517 | if (!HasError) |
518 | getStorage()->~storage_type(); |
519 | else |
520 | getErrorStorage()->~error_type(); |
521 | } |
522 | |
523 | /// Return false if there is an error. |
524 | explicit operator bool() { |
525 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
526 | Unchecked = HasError; |
527 | #endif |
528 | return !HasError; |
529 | } |
530 | |
531 | /// Returns a reference to the stored T value. |
532 | reference get() { |
533 | assertIsChecked(); |
534 | return *getStorage(); |
535 | } |
536 | |
537 | /// Returns a const reference to the stored T value. |
538 | const_reference get() const { |
539 | assertIsChecked(); |
540 | return const_cast<Expected<T> *>(this)->get(); |
541 | } |
542 | |
543 | /// Check that this Expected<T> is an error of type ErrT. |
544 | template <typename ErrT> bool errorIsA() const { |
545 | return HasError && (*getErrorStorage())->template isA<ErrT>(); |
546 | } |
547 | |
548 | /// Take ownership of the stored error. |
549 | /// After calling this the Expected<T> is in an indeterminate state that can |
550 | /// only be safely destructed. No further calls (beside the destructor) should |
551 | /// be made on the Expected<T> value. |
552 | Error takeError() { |
553 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
554 | Unchecked = false; |
555 | #endif |
556 | return HasError ? Error(std::move(*getErrorStorage())) : Error::success(); |
557 | } |
558 | |
559 | /// Returns a pointer to the stored T value. |
560 | pointer operator->() { |
561 | assertIsChecked(); |
562 | return toPointer(getStorage()); |
563 | } |
564 | |
565 | /// Returns a const pointer to the stored T value. |
566 | const_pointer operator->() const { |
567 | assertIsChecked(); |
568 | return toPointer(getStorage()); |
569 | } |
570 | |
571 | /// Returns a reference to the stored T value. |
572 | reference operator*() { |
573 | assertIsChecked(); |
574 | return *getStorage(); |
575 | } |
576 | |
577 | /// Returns a const reference to the stored T value. |
578 | const_reference operator*() const { |
579 | assertIsChecked(); |
580 | return *getStorage(); |
581 | } |
582 | |
583 | private: |
584 | template <class T1> |
585 | static bool compareThisIfSameType(const T1 &a, const T1 &b) { |
586 | return &a == &b; |
587 | } |
588 | |
589 | template <class T1, class T2> |
590 | static bool compareThisIfSameType(const T1 &a, const T2 &b) { |
591 | return false; |
592 | } |
593 | |
594 | template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) { |
595 | HasError = Other.HasError; |
596 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
597 | Unchecked = true; |
598 | Other.Unchecked = false; |
599 | #endif |
600 | |
601 | if (!HasError) |
602 | new (getStorage()) storage_type(std::move(*Other.getStorage())); |
603 | else |
604 | new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage())); |
605 | } |
606 | |
607 | template <class OtherT> void moveAssign(Expected<OtherT> &&Other) { |
608 | assertIsChecked(); |
609 | |
610 | if (compareThisIfSameType(*this, Other)) |
611 | return; |
612 | |
613 | this->~Expected(); |
614 | new (this) Expected(std::move(Other)); |
615 | } |
616 | |
617 | pointer toPointer(pointer Val) { return Val; } |
618 | |
619 | const_pointer toPointer(const_pointer Val) const { return Val; } |
620 | |
621 | pointer toPointer(wrap *Val) { return &Val->get(); } |
622 | |
623 | const_pointer toPointer(const wrap *Val) const { return &Val->get(); } |
624 | |
625 | storage_type *getStorage() { |
626 | assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!" ) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 626, __PRETTY_FUNCTION__)); |
627 | return reinterpret_cast<storage_type *>(TStorage.buffer); |
628 | } |
629 | |
630 | const storage_type *getStorage() const { |
631 | assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!" ) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 631, __PRETTY_FUNCTION__)); |
632 | return reinterpret_cast<const storage_type *>(TStorage.buffer); |
633 | } |
634 | |
635 | error_type *getErrorStorage() { |
636 | assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!" ) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 636, __PRETTY_FUNCTION__)); |
637 | return reinterpret_cast<error_type *>(ErrorStorage.buffer); |
638 | } |
639 | |
640 | const error_type *getErrorStorage() const { |
641 | assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!" ) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 641, __PRETTY_FUNCTION__)); |
642 | return reinterpret_cast<const error_type *>(ErrorStorage.buffer); |
643 | } |
644 | |
645 | // Used by ExpectedAsOutParameter to reset the checked flag. |
646 | void setUnchecked() { |
647 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
648 | Unchecked = true; |
649 | #endif |
650 | } |
651 | |
652 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
653 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) |
654 | LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) |
655 | void fatalUncheckedExpected() const { |
656 | dbgs() << "Expected<T> must be checked before access or destruction.\n"; |
657 | if (HasError) { |
658 | dbgs() << "Unchecked Expected<T> contained error:\n"; |
659 | (*getErrorStorage())->log(dbgs()); |
660 | } else |
661 | dbgs() << "Expected<T> value was in success state. (Note: Expected<T> " |
662 | "values in success mode must still be checked prior to being " |
663 | "destroyed).\n"; |
664 | abort(); |
665 | } |
666 | #endif |
667 | |
668 | void assertIsChecked() { |
669 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
670 | if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false)) |
671 | fatalUncheckedExpected(); |
672 | #endif |
673 | } |
674 | |
675 | union { |
676 | AlignedCharArrayUnion<storage_type> TStorage; |
677 | AlignedCharArrayUnion<error_type> ErrorStorage; |
678 | }; |
679 | bool HasError : 1; |
680 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 |
681 | bool Unchecked : 1; |
682 | #endif |
683 | }; |
684 | |
685 | /// Report a serious error, calling any installed error handler. See |
686 | /// ErrorHandling.h. |
687 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err, |
688 | bool gen_crash_diag = true); |
689 | |
690 | /// Report a fatal error if Err is a failure value. |
691 | /// |
692 | /// This function can be used to wrap calls to fallible functions ONLY when it |
693 | /// is known that the Error will always be a success value. E.g. |
694 | /// |
695 | /// @code{.cpp} |
696 | /// // foo only attempts the fallible operation if DoFallibleOperation is |
697 | /// // true. If DoFallibleOperation is false then foo always returns |
698 | /// // Error::success(). |
699 | /// Error foo(bool DoFallibleOperation); |
700 | /// |
701 | /// cantFail(foo(false)); |
702 | /// @endcode |
703 | inline void cantFail(Error Err, const char *Msg = nullptr) { |
704 | if (Err) { |
705 | if (!Msg) |
706 | Msg = "Failure value returned from cantFail wrapped call"; |
707 | #ifndef NDEBUG |
708 | std::string Str; |
709 | raw_string_ostream OS(Str); |
710 | OS << Msg << "\n" << Err; |
711 | Msg = OS.str().c_str(); |
712 | #endif |
713 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 713); |
714 | } |
715 | } |
716 | |
717 | /// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and |
718 | /// returns the contained value. |
719 | /// |
720 | /// This function can be used to wrap calls to fallible functions ONLY when it |
721 | /// is known that the Error will always be a success value. E.g. |
722 | /// |
723 | /// @code{.cpp} |
724 | /// // foo only attempts the fallible operation if DoFallibleOperation is |
725 | /// // true. If DoFallibleOperation is false then foo always returns an int. |
726 | /// Expected<int> foo(bool DoFallibleOperation); |
727 | /// |
728 | /// int X = cantFail(foo(false)); |
729 | /// @endcode |
730 | template <typename T> |
731 | T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) { |
732 | if (ValOrErr) |
733 | return std::move(*ValOrErr); |
734 | else { |
735 | if (!Msg) |
736 | Msg = "Failure value returned from cantFail wrapped call"; |
737 | #ifndef NDEBUG |
738 | std::string Str; |
739 | raw_string_ostream OS(Str); |
740 | auto E = ValOrErr.takeError(); |
741 | OS << Msg << "\n" << E; |
742 | Msg = OS.str().c_str(); |
743 | #endif |
744 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 744); |
745 | } |
746 | } |
747 | |
748 | /// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and |
749 | /// returns the contained reference. |
750 | /// |
751 | /// This function can be used to wrap calls to fallible functions ONLY when it |
752 | /// is known that the Error will always be a success value. E.g. |
753 | /// |
754 | /// @code{.cpp} |
755 | /// // foo only attempts the fallible operation if DoFallibleOperation is |
756 | /// // true. If DoFallibleOperation is false then foo always returns a Bar&. |
757 | /// Expected<Bar&> foo(bool DoFallibleOperation); |
758 | /// |
759 | /// Bar &X = cantFail(foo(false)); |
760 | /// @endcode |
761 | template <typename T> |
762 | T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) { |
763 | if (ValOrErr) |
764 | return *ValOrErr; |
765 | else { |
766 | if (!Msg) |
767 | Msg = "Failure value returned from cantFail wrapped call"; |
768 | #ifndef NDEBUG |
769 | std::string Str; |
770 | raw_string_ostream OS(Str); |
771 | auto E = ValOrErr.takeError(); |
772 | OS << Msg << "\n" << E; |
773 | Msg = OS.str().c_str(); |
774 | #endif |
775 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 775); |
776 | } |
777 | } |
778 | |
779 | /// Helper for testing applicability of, and applying, handlers for |
780 | /// ErrorInfo types. |
781 | template <typename HandlerT> |
782 | class ErrorHandlerTraits |
783 | : public ErrorHandlerTraits<decltype( |
784 | &std::remove_reference<HandlerT>::type::operator())> {}; |
785 | |
786 | // Specialization functions of the form 'Error (const ErrT&)'. |
787 | template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> { |
788 | public: |
789 | static bool appliesTo(const ErrorInfoBase &E) { |
790 | return E.template isA<ErrT>(); |
791 | } |
792 | |
793 | template <typename HandlerT> |
794 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { |
795 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 795, __PRETTY_FUNCTION__)); |
796 | return H(static_cast<ErrT &>(*E)); |
797 | } |
798 | }; |
799 | |
800 | // Specialization functions of the form 'void (const ErrT&)'. |
801 | template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> { |
802 | public: |
803 | static bool appliesTo(const ErrorInfoBase &E) { |
804 | return E.template isA<ErrT>(); |
805 | } |
806 | |
807 | template <typename HandlerT> |
808 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { |
809 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 809, __PRETTY_FUNCTION__)); |
810 | H(static_cast<ErrT &>(*E)); |
811 | return Error::success(); |
812 | } |
813 | }; |
814 | |
815 | /// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'. |
816 | template <typename ErrT> |
817 | class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> { |
818 | public: |
819 | static bool appliesTo(const ErrorInfoBase &E) { |
820 | return E.template isA<ErrT>(); |
821 | } |
822 | |
823 | template <typename HandlerT> |
824 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { |
825 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 825, __PRETTY_FUNCTION__)); |
826 | std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release())); |
827 | return H(std::move(SubE)); |
828 | } |
829 | }; |
830 | |
831 | /// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'. |
832 | template <typename ErrT> |
833 | class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> { |
834 | public: |
835 | static bool appliesTo(const ErrorInfoBase &E) { |
836 | return E.template isA<ErrT>(); |
837 | } |
838 | |
839 | template <typename HandlerT> |
840 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { |
841 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 841, __PRETTY_FUNCTION__)); |
842 | std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release())); |
843 | H(std::move(SubE)); |
844 | return Error::success(); |
845 | } |
846 | }; |
847 | |
848 | // Specialization for member functions of the form 'RetT (const ErrT&)'. |
849 | template <typename C, typename RetT, typename ErrT> |
850 | class ErrorHandlerTraits<RetT (C::*)(ErrT &)> |
851 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; |
852 | |
853 | // Specialization for member functions of the form 'RetT (const ErrT&) const'. |
854 | template <typename C, typename RetT, typename ErrT> |
855 | class ErrorHandlerTraits<RetT (C::*)(ErrT &) const> |
856 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; |
857 | |
858 | // Specialization for member functions of the form 'RetT (const ErrT&)'. |
859 | template <typename C, typename RetT, typename ErrT> |
860 | class ErrorHandlerTraits<RetT (C::*)(const ErrT &)> |
861 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; |
862 | |
863 | // Specialization for member functions of the form 'RetT (const ErrT&) const'. |
864 | template <typename C, typename RetT, typename ErrT> |
865 | class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const> |
866 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; |
867 | |
868 | /// Specialization for member functions of the form |
869 | /// 'RetT (std::unique_ptr<ErrT>)'. |
870 | template <typename C, typename RetT, typename ErrT> |
871 | class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)> |
872 | : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {}; |
873 | |
874 | /// Specialization for member functions of the form |
875 | /// 'RetT (std::unique_ptr<ErrT>) const'. |
876 | template <typename C, typename RetT, typename ErrT> |
877 | class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const> |
878 | : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {}; |
879 | |
880 | inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) { |
881 | return Error(std::move(Payload)); |
882 | } |
883 | |
884 | template <typename HandlerT, typename... HandlerTs> |
885 | Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload, |
886 | HandlerT &&Handler, HandlerTs &&... Handlers) { |
887 | if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload)) |
888 | return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler), |
889 | std::move(Payload)); |
890 | return handleErrorImpl(std::move(Payload), |
891 | std::forward<HandlerTs>(Handlers)...); |
892 | } |
893 | |
894 | /// Pass the ErrorInfo(s) contained in E to their respective handlers. Any |
895 | /// unhandled errors (or Errors returned by handlers) are re-concatenated and |
896 | /// returned. |
897 | /// Because this function returns an error, its result must also be checked |
898 | /// or returned. If you intend to handle all errors use handleAllErrors |
899 | /// (which returns void, and will abort() on unhandled errors) instead. |
900 | template <typename... HandlerTs> |
901 | Error handleErrors(Error E, HandlerTs &&... Hs) { |
902 | if (!E) |
903 | return Error::success(); |
904 | |
905 | std::unique_ptr<ErrorInfoBase> Payload = E.takePayload(); |
906 | |
907 | if (Payload->isA<ErrorList>()) { |
908 | ErrorList &List = static_cast<ErrorList &>(*Payload); |
909 | Error R; |
910 | for (auto &P : List.Payloads) |
911 | R = ErrorList::join( |
912 | std::move(R), |
913 | handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...)); |
914 | return R; |
915 | } |
916 | |
917 | return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...); |
918 | } |
919 | |
920 | /// Behaves the same as handleErrors, except that by contract all errors |
921 | /// *must* be handled by the given handlers (i.e. there must be no remaining |
922 | /// errors after running the handlers, or llvm_unreachable is called). |
923 | template <typename... HandlerTs> |
924 | void handleAllErrors(Error E, HandlerTs &&... Handlers) { |
925 | cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...)); |
926 | } |
927 | |
928 | /// Check that E is a non-error, then drop it. |
929 | /// If E is an error, llvm_unreachable will be called. |
930 | inline void handleAllErrors(Error E) { |
931 | cantFail(std::move(E)); |
932 | } |
933 | |
934 | /// Handle any errors (if present) in an Expected<T>, then try a recovery path. |
935 | /// |
936 | /// If the incoming value is a success value it is returned unmodified. If it |
937 | /// is a failure value then it the contained error is passed to handleErrors. |
938 | /// If handleErrors is able to handle the error then the RecoveryPath functor |
939 | /// is called to supply the final result. If handleErrors is not able to |
940 | /// handle all errors then the unhandled errors are returned. |
941 | /// |
942 | /// This utility enables the follow pattern: |
943 | /// |
944 | /// @code{.cpp} |
945 | /// enum FooStrategy { Aggressive, Conservative }; |
946 | /// Expected<Foo> foo(FooStrategy S); |
947 | /// |
948 | /// auto ResultOrErr = |
949 | /// handleExpected( |
950 | /// foo(Aggressive), |
951 | /// []() { return foo(Conservative); }, |
952 | /// [](AggressiveStrategyError&) { |
953 | /// // Implicitly conusme this - we'll recover by using a conservative |
954 | /// // strategy. |
955 | /// }); |
956 | /// |
957 | /// @endcode |
958 | template <typename T, typename RecoveryFtor, typename... HandlerTs> |
959 | Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath, |
960 | HandlerTs &&... Handlers) { |
961 | if (ValOrErr) |
962 | return ValOrErr; |
963 | |
964 | if (auto Err = handleErrors(ValOrErr.takeError(), |
965 | std::forward<HandlerTs>(Handlers)...)) |
966 | return std::move(Err); |
967 | |
968 | return RecoveryPath(); |
969 | } |
970 | |
971 | /// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner |
972 | /// will be printed before the first one is logged. A newline will be printed |
973 | /// after each error. |
974 | /// |
975 | /// This function is compatible with the helpers from Support/WithColor.h. You |
976 | /// can pass any of them as the OS. Please consider using them instead of |
977 | /// including 'error: ' in the ErrorBanner. |
978 | /// |
979 | /// This is useful in the base level of your program to allow clean termination |
980 | /// (allowing clean deallocation of resources, etc.), while reporting error |
981 | /// information to the user. |
982 | void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {}); |
983 | |
984 | /// Write all error messages (if any) in E to a string. The newline character |
985 | /// is used to separate error messages. |
986 | inline std::string toString(Error E) { |
987 | SmallVector<std::string, 2> Errors; |
988 | handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) { |
989 | Errors.push_back(EI.message()); |
990 | }); |
991 | return join(Errors.begin(), Errors.end(), "\n"); |
992 | } |
993 | |
994 | /// Consume a Error without doing anything. This method should be used |
995 | /// only where an error can be considered a reasonable and expected return |
996 | /// value. |
997 | /// |
998 | /// Uses of this method are potentially indicative of design problems: If it's |
999 | /// legitimate to do nothing while processing an "error", the error-producer |
1000 | /// might be more clearly refactored to return an Optional<T>. |
1001 | inline void consumeError(Error Err) { |
1002 | handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {}); |
1003 | } |
1004 | |
1005 | /// Convert an Expected to an Optional without doing anything. This method |
1006 | /// should be used only where an error can be considered a reasonable and |
1007 | /// expected return value. |
1008 | /// |
1009 | /// Uses of this method are potentially indicative of problems: perhaps the |
1010 | /// error should be propagated further, or the error-producer should just |
1011 | /// return an Optional in the first place. |
1012 | template <typename T> Optional<T> expectedToOptional(Expected<T> &&E) { |
1013 | if (E) |
1014 | return std::move(*E); |
1015 | consumeError(E.takeError()); |
1016 | return None; |
1017 | } |
1018 | |
1019 | /// Helper for converting an Error to a bool. |
1020 | /// |
1021 | /// This method returns true if Err is in an error state, or false if it is |
1022 | /// in a success state. Puts Err in a checked state in both cases (unlike |
1023 | /// Error::operator bool(), which only does this for success states). |
1024 | inline bool errorToBool(Error Err) { |
1025 | bool IsError = static_cast<bool>(Err); |
1026 | if (IsError) |
1027 | consumeError(std::move(Err)); |
1028 | return IsError; |
1029 | } |
1030 | |
1031 | /// Helper for Errors used as out-parameters. |
1032 | /// |
1033 | /// This helper is for use with the Error-as-out-parameter idiom, where an error |
1034 | /// is passed to a function or method by reference, rather than being returned. |
1035 | /// In such cases it is helpful to set the checked bit on entry to the function |
1036 | /// so that the error can be written to (unchecked Errors abort on assignment) |
1037 | /// and clear the checked bit on exit so that clients cannot accidentally forget |
1038 | /// to check the result. This helper performs these actions automatically using |
1039 | /// RAII: |
1040 | /// |
1041 | /// @code{.cpp} |
1042 | /// Result foo(Error &Err) { |
1043 | /// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set |
1044 | /// // <body of foo> |
1045 | /// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed. |
1046 | /// } |
1047 | /// @endcode |
1048 | /// |
1049 | /// ErrorAsOutParameter takes an Error* rather than Error& so that it can be |
1050 | /// used with optional Errors (Error pointers that are allowed to be null). If |
1051 | /// ErrorAsOutParameter took an Error reference, an instance would have to be |
1052 | /// created inside every condition that verified that Error was non-null. By |
1053 | /// taking an Error pointer we can just create one instance at the top of the |
1054 | /// function. |
1055 | class ErrorAsOutParameter { |
1056 | public: |
1057 | ErrorAsOutParameter(Error *Err) : Err(Err) { |
1058 | // Raise the checked bit if Err is success. |
1059 | if (Err) |
1060 | (void)!!*Err; |
1061 | } |
1062 | |
1063 | ~ErrorAsOutParameter() { |
1064 | // Clear the checked bit. |
1065 | if (Err && !*Err) |
1066 | *Err = Error::success(); |
1067 | } |
1068 | |
1069 | private: |
1070 | Error *Err; |
1071 | }; |
1072 | |
1073 | /// Helper for Expected<T>s used as out-parameters. |
1074 | /// |
1075 | /// See ErrorAsOutParameter. |
1076 | template <typename T> |
1077 | class ExpectedAsOutParameter { |
1078 | public: |
1079 | ExpectedAsOutParameter(Expected<T> *ValOrErr) |
1080 | : ValOrErr(ValOrErr) { |
1081 | if (ValOrErr) |
1082 | (void)!!*ValOrErr; |
1083 | } |
1084 | |
1085 | ~ExpectedAsOutParameter() { |
1086 | if (ValOrErr) |
1087 | ValOrErr->setUnchecked(); |
1088 | } |
1089 | |
1090 | private: |
1091 | Expected<T> *ValOrErr; |
1092 | }; |
1093 | |
1094 | /// This class wraps a std::error_code in a Error. |
1095 | /// |
1096 | /// This is useful if you're writing an interface that returns a Error |
1097 | /// (or Expected) and you want to call code that still returns |
1098 | /// std::error_codes. |
1099 | class ECError : public ErrorInfo<ECError> { |
1100 | friend Error errorCodeToError(std::error_code); |
1101 | |
1102 | virtual void anchor() override; |
1103 | |
1104 | public: |
1105 | void setErrorCode(std::error_code EC) { this->EC = EC; } |
1106 | std::error_code convertToErrorCode() const override { return EC; } |
1107 | void log(raw_ostream &OS) const override { OS << EC.message(); } |
1108 | |
1109 | // Used by ErrorInfo::classID. |
1110 | static char ID; |
1111 | |
1112 | protected: |
1113 | ECError() = default; |
1114 | ECError(std::error_code EC) : EC(EC) {} |
1115 | |
1116 | std::error_code EC; |
1117 | }; |
1118 | |
1119 | /// The value returned by this function can be returned from convertToErrorCode |
1120 | /// for Error values where no sensible translation to std::error_code exists. |
1121 | /// It should only be used in this situation, and should never be used where a |
1122 | /// sensible conversion to std::error_code is available, as attempts to convert |
1123 | /// to/from this error will result in a fatal error. (i.e. it is a programmatic |
1124 | ///error to try to convert such a value). |
1125 | std::error_code inconvertibleErrorCode(); |
1126 | |
1127 | /// Helper for converting an std::error_code to a Error. |
1128 | Error errorCodeToError(std::error_code EC); |
1129 | |
1130 | /// Helper for converting an ECError to a std::error_code. |
1131 | /// |
1132 | /// This method requires that Err be Error() or an ECError, otherwise it |
1133 | /// will trigger a call to abort(). |
1134 | std::error_code errorToErrorCode(Error Err); |
1135 | |
1136 | /// Convert an ErrorOr<T> to an Expected<T>. |
1137 | template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) { |
1138 | if (auto EC = EO.getError()) |
1139 | return errorCodeToError(EC); |
1140 | return std::move(*EO); |
1141 | } |
1142 | |
1143 | /// Convert an Expected<T> to an ErrorOr<T>. |
1144 | template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) { |
1145 | if (auto Err = E.takeError()) |
1146 | return errorToErrorCode(std::move(Err)); |
1147 | return std::move(*E); |
1148 | } |
1149 | |
1150 | /// This class wraps a string in an Error. |
1151 | /// |
1152 | /// StringError is useful in cases where the client is not expected to be able |
1153 | /// to consume the specific error message programmatically (for example, if the |
1154 | /// error message is to be presented to the user). |
1155 | /// |
1156 | /// StringError can also be used when additional information is to be printed |
1157 | /// along with a error_code message. Depending on the constructor called, this |
1158 | /// class can either display: |
1159 | /// 1. the error_code message (ECError behavior) |
1160 | /// 2. a string |
1161 | /// 3. the error_code message and a string |
1162 | /// |
1163 | /// These behaviors are useful when subtyping is required; for example, when a |
1164 | /// specific library needs an explicit error type. In the example below, |
1165 | /// PDBError is derived from StringError: |
1166 | /// |
1167 | /// @code{.cpp} |
1168 | /// Expected<int> foo() { |
1169 | /// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading, |
1170 | /// "Additional information"); |
1171 | /// } |
1172 | /// @endcode |
1173 | /// |
1174 | class StringError : public ErrorInfo<StringError> { |
1175 | public: |
1176 | static char ID; |
1177 | |
1178 | // Prints EC + S and converts to EC |
1179 | StringError(std::error_code EC, const Twine &S = Twine()); |
1180 | |
1181 | // Prints S and converts to EC |
1182 | StringError(const Twine &S, std::error_code EC); |
1183 | |
1184 | void log(raw_ostream &OS) const override; |
1185 | std::error_code convertToErrorCode() const override; |
1186 | |
1187 | const std::string &getMessage() const { return Msg; } |
1188 | |
1189 | private: |
1190 | std::string Msg; |
1191 | std::error_code EC; |
1192 | const bool PrintMsgOnly = false; |
1193 | }; |
1194 | |
1195 | /// Create formatted StringError object. |
1196 | template <typename... Ts> |
1197 | inline Error createStringError(std::error_code EC, char const *Fmt, |
1198 | const Ts &... Vals) { |
1199 | std::string Buffer; |
1200 | raw_string_ostream Stream(Buffer); |
1201 | Stream << format(Fmt, Vals...); |
1202 | return make_error<StringError>(Stream.str(), EC); |
1203 | } |
1204 | |
1205 | Error createStringError(std::error_code EC, char const *Msg); |
1206 | |
1207 | inline Error createStringError(std::error_code EC, const Twine &S) { |
1208 | return createStringError(EC, S.str().c_str()); |
1209 | } |
1210 | |
1211 | template <typename... Ts> |
1212 | inline Error createStringError(std::errc EC, char const *Fmt, |
1213 | const Ts &... Vals) { |
1214 | return createStringError(std::make_error_code(EC), Fmt, Vals...); |
1215 | } |
1216 | |
1217 | /// This class wraps a filename and another Error. |
1218 | /// |
1219 | /// In some cases, an error needs to live along a 'source' name, in order to |
1220 | /// show more detailed information to the user. |
1221 | class FileError final : public ErrorInfo<FileError> { |
1222 | |
1223 | friend Error createFileError(const Twine &, Error); |
1224 | friend Error createFileError(const Twine &, size_t, Error); |
1225 | |
1226 | public: |
1227 | void log(raw_ostream &OS) const override { |
1228 | assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()." ) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 1228, __PRETTY_FUNCTION__)); |
1229 | OS << "'" << FileName << "': "; |
1230 | if (Line.hasValue()) |
1231 | OS << "line " << Line.getValue() << ": "; |
1232 | Err->log(OS); |
1233 | } |
1234 | |
1235 | Error takeError() { return Error(std::move(Err)); } |
1236 | |
1237 | std::error_code convertToErrorCode() const override; |
1238 | |
1239 | // Used by ErrorInfo::classID. |
1240 | static char ID; |
1241 | |
1242 | private: |
1243 | FileError(const Twine &F, Optional<size_t> LineNum, |
1244 | std::unique_ptr<ErrorInfoBase> E) { |
1245 | assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value." ) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 1245, __PRETTY_FUNCTION__)); |
1246 | assert(!F.isTriviallyEmpty() &&((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty." ) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 1247, __PRETTY_FUNCTION__)) |
1247 | "The file name provided to FileError must not be empty.")((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty." ) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/Support/Error.h" , 1247, __PRETTY_FUNCTION__)); |
1248 | FileName = F.str(); |
1249 | Err = std::move(E); |
1250 | Line = std::move(LineNum); |
1251 | } |
1252 | |
1253 | static Error build(const Twine &F, Optional<size_t> Line, Error E) { |
1254 | return Error( |
1255 | std::unique_ptr<FileError>(new FileError(F, Line, E.takePayload()))); |
1256 | } |
1257 | |
1258 | std::string FileName; |
1259 | Optional<size_t> Line; |
1260 | std::unique_ptr<ErrorInfoBase> Err; |
1261 | }; |
1262 | |
1263 | /// Concatenate a source file path and/or name with an Error. The resulting |
1264 | /// Error is unchecked. |
1265 | inline Error createFileError(const Twine &F, Error E) { |
1266 | return FileError::build(F, Optional<size_t>(), std::move(E)); |
1267 | } |
1268 | |
1269 | /// Concatenate a source file path and/or name with line number and an Error. |
1270 | /// The resulting Error is unchecked. |
1271 | inline Error createFileError(const Twine &F, size_t Line, Error E) { |
1272 | return FileError::build(F, Optional<size_t>(Line), std::move(E)); |
1273 | } |
1274 | |
1275 | /// Concatenate a source file path and/or name with a std::error_code |
1276 | /// to form an Error object. |
1277 | inline Error createFileError(const Twine &F, std::error_code EC) { |
1278 | return createFileError(F, errorCodeToError(EC)); |
1279 | } |
1280 | |
1281 | /// Concatenate a source file path and/or name with line number and |
1282 | /// std::error_code to form an Error object. |
1283 | inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) { |
1284 | return createFileError(F, Line, errorCodeToError(EC)); |
1285 | } |
1286 | |
1287 | Error createFileError(const Twine &F, ErrorSuccess) = delete; |
1288 | |
1289 | /// Helper for check-and-exit error handling. |
1290 | /// |
1291 | /// For tool use only. NOT FOR USE IN LIBRARY CODE. |
1292 | /// |
1293 | class ExitOnError { |
1294 | public: |
1295 | /// Create an error on exit helper. |
1296 | ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1) |
1297 | : Banner(std::move(Banner)), |
1298 | GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {} |
1299 | |
1300 | /// Set the banner string for any errors caught by operator(). |
1301 | void setBanner(std::string Banner) { this->Banner = std::move(Banner); } |
1302 | |
1303 | /// Set the exit-code mapper function. |
1304 | void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) { |
1305 | this->GetExitCode = std::move(GetExitCode); |
1306 | } |
1307 | |
1308 | /// Check Err. If it's in a failure state log the error(s) and exit. |
1309 | void operator()(Error Err) const { checkError(std::move(Err)); } |
1310 | |
1311 | /// Check E. If it's in a success state then return the contained value. If |
1312 | /// it's in a failure state log the error(s) and exit. |
1313 | template <typename T> T operator()(Expected<T> &&E) const { |
1314 | checkError(E.takeError()); |
1315 | return std::move(*E); |
1316 | } |
1317 | |
1318 | /// Check E. If it's in a success state then return the contained reference. If |
1319 | /// it's in a failure state log the error(s) and exit. |
1320 | template <typename T> T& operator()(Expected<T&> &&E) const { |
1321 | checkError(E.takeError()); |
1322 | return *E; |
1323 | } |
1324 | |
1325 | private: |
1326 | void checkError(Error Err) const { |
1327 | if (Err) { |
1328 | int ExitCode = GetExitCode(Err); |
1329 | logAllUnhandledErrors(std::move(Err), errs(), Banner); |
1330 | exit(ExitCode); |
1331 | } |
1332 | } |
1333 | |
1334 | std::string Banner; |
1335 | std::function<int(const Error &)> GetExitCode; |
1336 | }; |
1337 | |
1338 | /// Conversion from Error to LLVMErrorRef for C error bindings. |
1339 | inline LLVMErrorRef wrap(Error Err) { |
1340 | return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release()); |
1341 | } |
1342 | |
1343 | /// Conversion from LLVMErrorRef to Error for C error bindings. |
1344 | inline Error unwrap(LLVMErrorRef ErrRef) { |
1345 | return Error(std::unique_ptr<ErrorInfoBase>( |
1346 | reinterpret_cast<ErrorInfoBase *>(ErrRef))); |
1347 | } |
1348 | |
1349 | } // end namespace llvm |
1350 | |
1351 | #endif // LLVM_SUPPORT_ERROR_H |