SourceManager.cpp revision e23ac65af568ffe611b0990818ac3a57c856a4d8
1//===--- SourceManager.cpp - Track and cache source files -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements the SourceManager interface. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Basic/SourceManager.h" 15#include "clang/Basic/SourceManagerInternals.h" 16#include "clang/Basic/Diagnostic.h" 17#include "clang/Basic/FileManager.h" 18#include "llvm/ADT/StringSwitch.h" 19#include "llvm/ADT/Optional.h" 20#include "llvm/Support/Compiler.h" 21#include "llvm/Support/MemoryBuffer.h" 22#include "llvm/Support/raw_ostream.h" 23#include "llvm/Support/Path.h" 24#include <algorithm> 25#include <string> 26#include <cstring> 27#include <sys/stat.h> 28 29using namespace clang; 30using namespace SrcMgr; 31using llvm::MemoryBuffer; 32 33//===----------------------------------------------------------------------===// 34// SourceManager Helper Classes 35//===----------------------------------------------------------------------===// 36 37ContentCache::~ContentCache() { 38 if (shouldFreeBuffer()) 39 delete Buffer.getPointer(); 40} 41 42/// getSizeBytesMapped - Returns the number of bytes actually mapped for 43/// this ContentCache. This can be 0 if the MemBuffer was not actually 44/// instantiated. 45unsigned ContentCache::getSizeBytesMapped() const { 46 return Buffer.getPointer() ? Buffer.getPointer()->getBufferSize() : 0; 47} 48 49/// getSize - Returns the size of the content encapsulated by this ContentCache. 50/// This can be the size of the source file or the size of an arbitrary 51/// scratch buffer. If the ContentCache encapsulates a source file, that 52/// file is not lazily brought in from disk to satisfy this query. 53unsigned ContentCache::getSize() const { 54 return Buffer.getPointer() ? (unsigned) Buffer.getPointer()->getBufferSize() 55 : (unsigned) ContentsEntry->getSize(); 56} 57 58void ContentCache::replaceBuffer(const llvm::MemoryBuffer *B, 59 bool DoNotFree) { 60 assert(B != Buffer.getPointer()); 61 62 if (shouldFreeBuffer()) 63 delete Buffer.getPointer(); 64 Buffer.setPointer(B); 65 Buffer.setInt(DoNotFree? DoNotFreeFlag : 0); 66} 67 68const llvm::MemoryBuffer *ContentCache::getBuffer(Diagnostic &Diag, 69 const SourceManager &SM, 70 SourceLocation Loc, 71 bool *Invalid) const { 72 // Lazily create the Buffer for ContentCaches that wrap files. If we already 73 // computed it, just return what we have. 74 if (Buffer.getPointer() || ContentsEntry == 0) { 75 if (Invalid) 76 *Invalid = isBufferInvalid(); 77 78 return Buffer.getPointer(); 79 } 80 81 std::string ErrorStr; 82 Buffer.setPointer(SM.getFileManager().getBufferForFile(ContentsEntry, &ErrorStr)); 83 84 // If we were unable to open the file, then we are in an inconsistent 85 // situation where the content cache referenced a file which no longer 86 // exists. Most likely, we were using a stat cache with an invalid entry but 87 // the file could also have been removed during processing. Since we can't 88 // really deal with this situation, just create an empty buffer. 89 // 90 // FIXME: This is definitely not ideal, but our immediate clients can't 91 // currently handle returning a null entry here. Ideally we should detect 92 // that we are in an inconsistent situation and error out as quickly as 93 // possible. 94 if (!Buffer.getPointer()) { 95 const llvm::StringRef FillStr("<<<MISSING SOURCE FILE>>>\n"); 96 Buffer.setPointer(MemoryBuffer::getNewMemBuffer(ContentsEntry->getSize(), 97 "<invalid>")); 98 char *Ptr = const_cast<char*>(Buffer.getPointer()->getBufferStart()); 99 for (unsigned i = 0, e = ContentsEntry->getSize(); i != e; ++i) 100 Ptr[i] = FillStr[i % FillStr.size()]; 101 102 if (Diag.isDiagnosticInFlight()) 103 Diag.SetDelayedDiagnostic(diag::err_cannot_open_file, 104 ContentsEntry->getName(), ErrorStr); 105 else 106 Diag.Report(Loc, diag::err_cannot_open_file) 107 << ContentsEntry->getName() << ErrorStr; 108 109 Buffer.setInt(Buffer.getInt() | InvalidFlag); 110 111 if (Invalid) *Invalid = true; 112 return Buffer.getPointer(); 113 } 114 115 // Check that the file's size is the same as in the file entry (which may 116 // have come from a stat cache). 117 if (getRawBuffer()->getBufferSize() != (size_t)ContentsEntry->getSize()) { 118 if (Diag.isDiagnosticInFlight()) 119 Diag.SetDelayedDiagnostic(diag::err_file_modified, 120 ContentsEntry->getName()); 121 else 122 Diag.Report(Loc, diag::err_file_modified) 123 << ContentsEntry->getName(); 124 125 Buffer.setInt(Buffer.getInt() | InvalidFlag); 126 if (Invalid) *Invalid = true; 127 return Buffer.getPointer(); 128 } 129 130 // If the buffer is valid, check to see if it has a UTF Byte Order Mark 131 // (BOM). We only support UTF-8 with and without a BOM right now. See 132 // http://en.wikipedia.org/wiki/Byte_order_mark for more information. 133 llvm::StringRef BufStr = Buffer.getPointer()->getBuffer(); 134 const char *InvalidBOM = llvm::StringSwitch<const char *>(BufStr) 135 .StartsWith("\xFE\xFF", "UTF-16 (BE)") 136 .StartsWith("\xFF\xFE", "UTF-16 (LE)") 137 .StartsWith("\x00\x00\xFE\xFF", "UTF-32 (BE)") 138 .StartsWith("\xFF\xFE\x00\x00", "UTF-32 (LE)") 139 .StartsWith("\x2B\x2F\x76", "UTF-7") 140 .StartsWith("\xF7\x64\x4C", "UTF-1") 141 .StartsWith("\xDD\x73\x66\x73", "UTF-EBCDIC") 142 .StartsWith("\x0E\xFE\xFF", "SDSU") 143 .StartsWith("\xFB\xEE\x28", "BOCU-1") 144 .StartsWith("\x84\x31\x95\x33", "GB-18030") 145 .Default(0); 146 147 if (InvalidBOM) { 148 Diag.Report(Loc, diag::err_unsupported_bom) 149 << InvalidBOM << ContentsEntry->getName(); 150 Buffer.setInt(Buffer.getInt() | InvalidFlag); 151 } 152 153 if (Invalid) 154 *Invalid = isBufferInvalid(); 155 156 return Buffer.getPointer(); 157} 158 159unsigned LineTableInfo::getLineTableFilenameID(const char *Ptr, unsigned Len) { 160 // Look up the filename in the string table, returning the pre-existing value 161 // if it exists. 162 llvm::StringMapEntry<unsigned> &Entry = 163 FilenameIDs.GetOrCreateValue(Ptr, Ptr+Len, ~0U); 164 if (Entry.getValue() != ~0U) 165 return Entry.getValue(); 166 167 // Otherwise, assign this the next available ID. 168 Entry.setValue(FilenamesByID.size()); 169 FilenamesByID.push_back(&Entry); 170 return FilenamesByID.size()-1; 171} 172 173/// AddLineNote - Add a line note to the line table that indicates that there 174/// is a #line at the specified FID/Offset location which changes the presumed 175/// location to LineNo/FilenameID. 176void LineTableInfo::AddLineNote(unsigned FID, unsigned Offset, 177 unsigned LineNo, int FilenameID) { 178 std::vector<LineEntry> &Entries = LineEntries[FID]; 179 180 assert((Entries.empty() || Entries.back().FileOffset < Offset) && 181 "Adding line entries out of order!"); 182 183 SrcMgr::CharacteristicKind Kind = SrcMgr::C_User; 184 unsigned IncludeOffset = 0; 185 186 if (!Entries.empty()) { 187 // If this is a '#line 4' after '#line 42 "foo.h"', make sure to remember 188 // that we are still in "foo.h". 189 if (FilenameID == -1) 190 FilenameID = Entries.back().FilenameID; 191 192 // If we are after a line marker that switched us to system header mode, or 193 // that set #include information, preserve it. 194 Kind = Entries.back().FileKind; 195 IncludeOffset = Entries.back().IncludeOffset; 196 } 197 198 Entries.push_back(LineEntry::get(Offset, LineNo, FilenameID, Kind, 199 IncludeOffset)); 200} 201 202/// AddLineNote This is the same as the previous version of AddLineNote, but is 203/// used for GNU line markers. If EntryExit is 0, then this doesn't change the 204/// presumed #include stack. If it is 1, this is a file entry, if it is 2 then 205/// this is a file exit. FileKind specifies whether this is a system header or 206/// extern C system header. 207void LineTableInfo::AddLineNote(unsigned FID, unsigned Offset, 208 unsigned LineNo, int FilenameID, 209 unsigned EntryExit, 210 SrcMgr::CharacteristicKind FileKind) { 211 assert(FilenameID != -1 && "Unspecified filename should use other accessor"); 212 213 std::vector<LineEntry> &Entries = LineEntries[FID]; 214 215 assert((Entries.empty() || Entries.back().FileOffset < Offset) && 216 "Adding line entries out of order!"); 217 218 unsigned IncludeOffset = 0; 219 if (EntryExit == 0) { // No #include stack change. 220 IncludeOffset = Entries.empty() ? 0 : Entries.back().IncludeOffset; 221 } else if (EntryExit == 1) { 222 IncludeOffset = Offset-1; 223 } else if (EntryExit == 2) { 224 assert(!Entries.empty() && Entries.back().IncludeOffset && 225 "PPDirectives should have caught case when popping empty include stack"); 226 227 // Get the include loc of the last entries' include loc as our include loc. 228 IncludeOffset = 0; 229 if (const LineEntry *PrevEntry = 230 FindNearestLineEntry(FID, Entries.back().IncludeOffset)) 231 IncludeOffset = PrevEntry->IncludeOffset; 232 } 233 234 Entries.push_back(LineEntry::get(Offset, LineNo, FilenameID, FileKind, 235 IncludeOffset)); 236} 237 238 239/// FindNearestLineEntry - Find the line entry nearest to FID that is before 240/// it. If there is no line entry before Offset in FID, return null. 241const LineEntry *LineTableInfo::FindNearestLineEntry(unsigned FID, 242 unsigned Offset) { 243 const std::vector<LineEntry> &Entries = LineEntries[FID]; 244 assert(!Entries.empty() && "No #line entries for this FID after all!"); 245 246 // It is very common for the query to be after the last #line, check this 247 // first. 248 if (Entries.back().FileOffset <= Offset) 249 return &Entries.back(); 250 251 // Do a binary search to find the maximal element that is still before Offset. 252 std::vector<LineEntry>::const_iterator I = 253 std::upper_bound(Entries.begin(), Entries.end(), Offset); 254 if (I == Entries.begin()) return 0; 255 return &*--I; 256} 257 258/// \brief Add a new line entry that has already been encoded into 259/// the internal representation of the line table. 260void LineTableInfo::AddEntry(unsigned FID, 261 const std::vector<LineEntry> &Entries) { 262 LineEntries[FID] = Entries; 263} 264 265/// getLineTableFilenameID - Return the uniqued ID for the specified filename. 266/// 267unsigned SourceManager::getLineTableFilenameID(const char *Ptr, unsigned Len) { 268 if (LineTable == 0) 269 LineTable = new LineTableInfo(); 270 return LineTable->getLineTableFilenameID(Ptr, Len); 271} 272 273 274/// AddLineNote - Add a line note to the line table for the FileID and offset 275/// specified by Loc. If FilenameID is -1, it is considered to be 276/// unspecified. 277void SourceManager::AddLineNote(SourceLocation Loc, unsigned LineNo, 278 int FilenameID) { 279 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 280 281 bool Invalid = false; 282 const SLocEntry &Entry = getSLocEntry(LocInfo.first, &Invalid); 283 if (!Entry.isFile() || Invalid) 284 return; 285 286 const SrcMgr::FileInfo &FileInfo = Entry.getFile(); 287 288 // Remember that this file has #line directives now if it doesn't already. 289 const_cast<SrcMgr::FileInfo&>(FileInfo).setHasLineDirectives(); 290 291 if (LineTable == 0) 292 LineTable = new LineTableInfo(); 293 LineTable->AddLineNote(LocInfo.first.ID, LocInfo.second, LineNo, FilenameID); 294} 295 296/// AddLineNote - Add a GNU line marker to the line table. 297void SourceManager::AddLineNote(SourceLocation Loc, unsigned LineNo, 298 int FilenameID, bool IsFileEntry, 299 bool IsFileExit, bool IsSystemHeader, 300 bool IsExternCHeader) { 301 // If there is no filename and no flags, this is treated just like a #line, 302 // which does not change the flags of the previous line marker. 303 if (FilenameID == -1) { 304 assert(!IsFileEntry && !IsFileExit && !IsSystemHeader && !IsExternCHeader && 305 "Can't set flags without setting the filename!"); 306 return AddLineNote(Loc, LineNo, FilenameID); 307 } 308 309 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 310 311 bool Invalid = false; 312 const SLocEntry &Entry = getSLocEntry(LocInfo.first, &Invalid); 313 if (!Entry.isFile() || Invalid) 314 return; 315 316 const SrcMgr::FileInfo &FileInfo = Entry.getFile(); 317 318 // Remember that this file has #line directives now if it doesn't already. 319 const_cast<SrcMgr::FileInfo&>(FileInfo).setHasLineDirectives(); 320 321 if (LineTable == 0) 322 LineTable = new LineTableInfo(); 323 324 SrcMgr::CharacteristicKind FileKind; 325 if (IsExternCHeader) 326 FileKind = SrcMgr::C_ExternCSystem; 327 else if (IsSystemHeader) 328 FileKind = SrcMgr::C_System; 329 else 330 FileKind = SrcMgr::C_User; 331 332 unsigned EntryExit = 0; 333 if (IsFileEntry) 334 EntryExit = 1; 335 else if (IsFileExit) 336 EntryExit = 2; 337 338 LineTable->AddLineNote(LocInfo.first.ID, LocInfo.second, LineNo, FilenameID, 339 EntryExit, FileKind); 340} 341 342LineTableInfo &SourceManager::getLineTable() { 343 if (LineTable == 0) 344 LineTable = new LineTableInfo(); 345 return *LineTable; 346} 347 348//===----------------------------------------------------------------------===// 349// Private 'Create' methods. 350//===----------------------------------------------------------------------===// 351 352SourceManager::SourceManager(Diagnostic &Diag, FileManager &FileMgr) 353 : Diag(Diag), FileMgr(FileMgr), OverridenFilesKeepOriginalName(true), 354 ExternalSLocEntries(0), LineTable(0), NumLinearScans(0), 355 NumBinaryProbes(0), FakeBufferForRecovery(0) { 356 clearIDTables(); 357 Diag.setSourceManager(this); 358} 359 360SourceManager::~SourceManager() { 361 delete LineTable; 362 363 // Delete FileEntry objects corresponding to content caches. Since the actual 364 // content cache objects are bump pointer allocated, we just have to run the 365 // dtors, but we call the deallocate method for completeness. 366 for (unsigned i = 0, e = MemBufferInfos.size(); i != e; ++i) { 367 MemBufferInfos[i]->~ContentCache(); 368 ContentCacheAlloc.Deallocate(MemBufferInfos[i]); 369 } 370 for (llvm::DenseMap<const FileEntry*, SrcMgr::ContentCache*>::iterator 371 I = FileInfos.begin(), E = FileInfos.end(); I != E; ++I) { 372 I->second->~ContentCache(); 373 ContentCacheAlloc.Deallocate(I->second); 374 } 375 376 delete FakeBufferForRecovery; 377} 378 379void SourceManager::clearIDTables() { 380 MainFileID = FileID(); 381 SLocEntryTable.clear(); 382 LastLineNoFileIDQuery = FileID(); 383 LastLineNoContentCache = 0; 384 LastFileIDLookup = FileID(); 385 386 if (LineTable) 387 LineTable->clear(); 388 389 // Use up FileID #0 as an invalid instantiation. 390 NextOffset = 0; 391 createInstantiationLoc(SourceLocation(),SourceLocation(),SourceLocation(), 1); 392} 393 394/// getOrCreateContentCache - Create or return a cached ContentCache for the 395/// specified file. 396const ContentCache * 397SourceManager::getOrCreateContentCache(const FileEntry *FileEnt) { 398 assert(FileEnt && "Didn't specify a file entry to use?"); 399 400 // Do we already have information about this file? 401 ContentCache *&Entry = FileInfos[FileEnt]; 402 if (Entry) return Entry; 403 404 // Nope, create a new Cache entry. Make sure it is at least 8-byte aligned 405 // so that FileInfo can use the low 3 bits of the pointer for its own 406 // nefarious purposes. 407 unsigned EntryAlign = llvm::AlignOf<ContentCache>::Alignment; 408 EntryAlign = std::max(8U, EntryAlign); 409 Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign); 410 411 // If the file contents are overridden with contents from another file, 412 // pass that file to ContentCache. 413 llvm::DenseMap<const FileEntry *, const FileEntry *>::iterator 414 overI = OverriddenFiles.find(FileEnt); 415 if (overI == OverriddenFiles.end()) 416 new (Entry) ContentCache(FileEnt); 417 else 418 new (Entry) ContentCache(OverridenFilesKeepOriginalName ? FileEnt 419 : overI->second, 420 overI->second); 421 422 return Entry; 423} 424 425 426/// createMemBufferContentCache - Create a new ContentCache for the specified 427/// memory buffer. This does no caching. 428const ContentCache* 429SourceManager::createMemBufferContentCache(const MemoryBuffer *Buffer) { 430 // Add a new ContentCache to the MemBufferInfos list and return it. Make sure 431 // it is at least 8-byte aligned so that FileInfo can use the low 3 bits of 432 // the pointer for its own nefarious purposes. 433 unsigned EntryAlign = llvm::AlignOf<ContentCache>::Alignment; 434 EntryAlign = std::max(8U, EntryAlign); 435 ContentCache *Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign); 436 new (Entry) ContentCache(); 437 MemBufferInfos.push_back(Entry); 438 Entry->setBuffer(Buffer); 439 return Entry; 440} 441 442void SourceManager::PreallocateSLocEntries(ExternalSLocEntrySource *Source, 443 unsigned NumSLocEntries, 444 unsigned NextOffset) { 445 ExternalSLocEntries = Source; 446 this->NextOffset = NextOffset; 447 unsigned CurPrealloc = SLocEntryLoaded.size(); 448 // If we've ever preallocated, we must not count the dummy entry. 449 if (CurPrealloc) --CurPrealloc; 450 SLocEntryLoaded.resize(NumSLocEntries + 1); 451 SLocEntryLoaded[0] = true; 452 SLocEntryTable.resize(SLocEntryTable.size() + NumSLocEntries - CurPrealloc); 453} 454 455void SourceManager::ClearPreallocatedSLocEntries() { 456 unsigned I = 0; 457 for (unsigned N = SLocEntryLoaded.size(); I != N; ++I) 458 if (!SLocEntryLoaded[I]) 459 break; 460 461 // We've already loaded all preallocated source location entries. 462 if (I == SLocEntryLoaded.size()) 463 return; 464 465 // Remove everything from location I onward. 466 SLocEntryTable.resize(I); 467 SLocEntryLoaded.clear(); 468 ExternalSLocEntries = 0; 469} 470 471/// \brief As part of recovering from missing or changed content, produce a 472/// fake, non-empty buffer. 473const llvm::MemoryBuffer *SourceManager::getFakeBufferForRecovery() const { 474 if (!FakeBufferForRecovery) 475 FakeBufferForRecovery 476 = llvm::MemoryBuffer::getMemBuffer("<<<INVALID BUFFER>>"); 477 478 return FakeBufferForRecovery; 479} 480 481//===----------------------------------------------------------------------===// 482// Methods to create new FileID's and instantiations. 483//===----------------------------------------------------------------------===// 484 485/// createFileID - Create a new FileID for the specified ContentCache and 486/// include position. This works regardless of whether the ContentCache 487/// corresponds to a file or some other input source. 488FileID SourceManager::createFileID(const ContentCache *File, 489 SourceLocation IncludePos, 490 SrcMgr::CharacteristicKind FileCharacter, 491 unsigned PreallocatedID, 492 unsigned Offset) { 493 if (PreallocatedID) { 494 // If we're filling in a preallocated ID, just load in the file 495 // entry and return. 496 assert(PreallocatedID < SLocEntryLoaded.size() && 497 "Preallocate ID out-of-range"); 498 assert(!SLocEntryLoaded[PreallocatedID] && 499 "Source location entry already loaded"); 500 assert(Offset && "Preallocate source location cannot have zero offset"); 501 SLocEntryTable[PreallocatedID] 502 = SLocEntry::get(Offset, FileInfo::get(IncludePos, File, FileCharacter)); 503 SLocEntryLoaded[PreallocatedID] = true; 504 FileID FID = FileID::get(PreallocatedID); 505 return FID; 506 } 507 508 SLocEntryTable.push_back(SLocEntry::get(NextOffset, 509 FileInfo::get(IncludePos, File, 510 FileCharacter))); 511 unsigned FileSize = File->getSize(); 512 assert(NextOffset+FileSize+1 > NextOffset && "Ran out of source locations!"); 513 NextOffset += FileSize+1; 514 515 // Set LastFileIDLookup to the newly created file. The next getFileID call is 516 // almost guaranteed to be from that file. 517 FileID FID = FileID::get(SLocEntryTable.size()-1); 518 return LastFileIDLookup = FID; 519} 520 521/// createInstantiationLoc - Return a new SourceLocation that encodes the fact 522/// that a token from SpellingLoc should actually be referenced from 523/// InstantiationLoc. 524SourceLocation SourceManager::createInstantiationLoc(SourceLocation SpellingLoc, 525 SourceLocation ILocStart, 526 SourceLocation ILocEnd, 527 unsigned TokLength, 528 unsigned PreallocatedID, 529 unsigned Offset) { 530 InstantiationInfo II = InstantiationInfo::get(ILocStart,ILocEnd, SpellingLoc); 531 if (PreallocatedID) { 532 // If we're filling in a preallocated ID, just load in the 533 // instantiation entry and return. 534 assert(PreallocatedID < SLocEntryLoaded.size() && 535 "Preallocate ID out-of-range"); 536 assert(!SLocEntryLoaded[PreallocatedID] && 537 "Source location entry already loaded"); 538 assert(Offset && "Preallocate source location cannot have zero offset"); 539 SLocEntryTable[PreallocatedID] = SLocEntry::get(Offset, II); 540 SLocEntryLoaded[PreallocatedID] = true; 541 return SourceLocation::getMacroLoc(Offset); 542 } 543 SLocEntryTable.push_back(SLocEntry::get(NextOffset, II)); 544 assert(NextOffset+TokLength+1 > NextOffset && "Ran out of source locations!"); 545 NextOffset += TokLength+1; 546 return SourceLocation::getMacroLoc(NextOffset-(TokLength+1)); 547} 548 549const llvm::MemoryBuffer * 550SourceManager::getMemoryBufferForFile(const FileEntry *File, 551 bool *Invalid) { 552 const SrcMgr::ContentCache *IR = getOrCreateContentCache(File); 553 assert(IR && "getOrCreateContentCache() cannot return NULL"); 554 return IR->getBuffer(Diag, *this, SourceLocation(), Invalid); 555} 556 557void SourceManager::overrideFileContents(const FileEntry *SourceFile, 558 const llvm::MemoryBuffer *Buffer, 559 bool DoNotFree) { 560 const SrcMgr::ContentCache *IR = getOrCreateContentCache(SourceFile); 561 assert(IR && "getOrCreateContentCache() cannot return NULL"); 562 563 const_cast<SrcMgr::ContentCache *>(IR)->replaceBuffer(Buffer, DoNotFree); 564} 565 566void SourceManager::overrideFileContents(const FileEntry *SourceFile, 567 const FileEntry *NewFile) { 568 assert(SourceFile->getSize() == NewFile->getSize() && 569 "Different sizes, use the FileManager to create a virtual file with " 570 "the correct size"); 571 assert(FileInfos.count(SourceFile) == 0 && 572 "This function should be called at the initialization stage, before " 573 "any parsing occurs."); 574 OverriddenFiles[SourceFile] = NewFile; 575} 576 577llvm::StringRef SourceManager::getBufferData(FileID FID, bool *Invalid) const { 578 bool MyInvalid = false; 579 const SLocEntry &SLoc = getSLocEntry(FID.ID, &MyInvalid); 580 if (!SLoc.isFile() || MyInvalid) { 581 if (Invalid) 582 *Invalid = true; 583 return "<<<<<INVALID SOURCE LOCATION>>>>>"; 584 } 585 586 const llvm::MemoryBuffer *Buf 587 = SLoc.getFile().getContentCache()->getBuffer(Diag, *this, SourceLocation(), 588 &MyInvalid); 589 if (Invalid) 590 *Invalid = MyInvalid; 591 592 if (MyInvalid) 593 return "<<<<<INVALID SOURCE LOCATION>>>>>"; 594 595 return Buf->getBuffer(); 596} 597 598//===----------------------------------------------------------------------===// 599// SourceLocation manipulation methods. 600//===----------------------------------------------------------------------===// 601 602/// getFileIDSlow - Return the FileID for a SourceLocation. This is a very hot 603/// method that is used for all SourceManager queries that start with a 604/// SourceLocation object. It is responsible for finding the entry in 605/// SLocEntryTable which contains the specified location. 606/// 607FileID SourceManager::getFileIDSlow(unsigned SLocOffset) const { 608 if (!SLocOffset) 609 return FileID::get(0); 610 611 // After the first and second level caches, I see two common sorts of 612 // behavior: 1) a lot of searched FileID's are "near" the cached file location 613 // or are "near" the cached instantiation location. 2) others are just 614 // completely random and may be a very long way away. 615 // 616 // To handle this, we do a linear search for up to 8 steps to catch #1 quickly 617 // then we fall back to a less cache efficient, but more scalable, binary 618 // search to find the location. 619 620 // See if this is near the file point - worst case we start scanning from the 621 // most newly created FileID. 622 std::vector<SrcMgr::SLocEntry>::const_iterator I; 623 624 if (SLocEntryTable[LastFileIDLookup.ID].getOffset() < SLocOffset) { 625 // Neither loc prunes our search. 626 I = SLocEntryTable.end(); 627 } else { 628 // Perhaps it is near the file point. 629 I = SLocEntryTable.begin()+LastFileIDLookup.ID; 630 } 631 632 // Find the FileID that contains this. "I" is an iterator that points to a 633 // FileID whose offset is known to be larger than SLocOffset. 634 unsigned NumProbes = 0; 635 while (1) { 636 --I; 637 if (ExternalSLocEntries) { 638 bool Invalid = false; 639 getSLocEntry(FileID::get(I - SLocEntryTable.begin()), &Invalid); 640 if (Invalid) 641 return FileID::get(0); 642 } 643 644 if (I->getOffset() <= SLocOffset) { 645#if 0 646 printf("lin %d -> %d [%s] %d %d\n", SLocOffset, 647 I-SLocEntryTable.begin(), 648 I->isInstantiation() ? "inst" : "file", 649 LastFileIDLookup.ID, int(SLocEntryTable.end()-I)); 650#endif 651 FileID Res = FileID::get(I-SLocEntryTable.begin()); 652 653 // If this isn't an instantiation, remember it. We have good locality 654 // across FileID lookups. 655 if (!I->isInstantiation()) 656 LastFileIDLookup = Res; 657 NumLinearScans += NumProbes+1; 658 return Res; 659 } 660 if (++NumProbes == 8) 661 break; 662 } 663 664 // Convert "I" back into an index. We know that it is an entry whose index is 665 // larger than the offset we are looking for. 666 unsigned GreaterIndex = I-SLocEntryTable.begin(); 667 // LessIndex - This is the lower bound of the range that we're searching. 668 // We know that the offset corresponding to the FileID is is less than 669 // SLocOffset. 670 unsigned LessIndex = 0; 671 NumProbes = 0; 672 while (1) { 673 bool Invalid = false; 674 unsigned MiddleIndex = (GreaterIndex-LessIndex)/2+LessIndex; 675 unsigned MidOffset = getSLocEntry(FileID::get(MiddleIndex), &Invalid) 676 .getOffset(); 677 if (Invalid) 678 return FileID::get(0); 679 680 ++NumProbes; 681 682 // If the offset of the midpoint is too large, chop the high side of the 683 // range to the midpoint. 684 if (MidOffset > SLocOffset) { 685 GreaterIndex = MiddleIndex; 686 continue; 687 } 688 689 // If the middle index contains the value, succeed and return. 690 if (isOffsetInFileID(FileID::get(MiddleIndex), SLocOffset)) { 691#if 0 692 printf("bin %d -> %d [%s] %d %d\n", SLocOffset, 693 I-SLocEntryTable.begin(), 694 I->isInstantiation() ? "inst" : "file", 695 LastFileIDLookup.ID, int(SLocEntryTable.end()-I)); 696#endif 697 FileID Res = FileID::get(MiddleIndex); 698 699 // If this isn't an instantiation, remember it. We have good locality 700 // across FileID lookups. 701 if (!I->isInstantiation()) 702 LastFileIDLookup = Res; 703 NumBinaryProbes += NumProbes; 704 return Res; 705 } 706 707 // Otherwise, move the low-side up to the middle index. 708 LessIndex = MiddleIndex; 709 } 710} 711 712SourceLocation SourceManager:: 713getInstantiationLocSlowCase(SourceLocation Loc) const { 714 do { 715 // Note: If Loc indicates an offset into a token that came from a macro 716 // expansion (e.g. the 5th character of the token) we do not want to add 717 // this offset when going to the instantiation location. The instatiation 718 // location is the macro invocation, which the offset has nothing to do 719 // with. This is unlike when we get the spelling loc, because the offset 720 // directly correspond to the token whose spelling we're inspecting. 721 Loc = getSLocEntry(getFileID(Loc)).getInstantiation() 722 .getInstantiationLocStart(); 723 } while (!Loc.isFileID()); 724 725 return Loc; 726} 727 728SourceLocation SourceManager::getSpellingLocSlowCase(SourceLocation Loc) const { 729 do { 730 std::pair<FileID, unsigned> LocInfo = getDecomposedLoc(Loc); 731 Loc = getSLocEntry(LocInfo.first).getInstantiation().getSpellingLoc(); 732 Loc = Loc.getFileLocWithOffset(LocInfo.second); 733 } while (!Loc.isFileID()); 734 return Loc; 735} 736 737 738std::pair<FileID, unsigned> 739SourceManager::getDecomposedInstantiationLocSlowCase(const SrcMgr::SLocEntry *E, 740 unsigned Offset) const { 741 // If this is an instantiation record, walk through all the instantiation 742 // points. 743 FileID FID; 744 SourceLocation Loc; 745 do { 746 Loc = E->getInstantiation().getInstantiationLocStart(); 747 748 FID = getFileID(Loc); 749 E = &getSLocEntry(FID); 750 Offset += Loc.getOffset()-E->getOffset(); 751 } while (!Loc.isFileID()); 752 753 return std::make_pair(FID, Offset); 754} 755 756std::pair<FileID, unsigned> 757SourceManager::getDecomposedSpellingLocSlowCase(const SrcMgr::SLocEntry *E, 758 unsigned Offset) const { 759 // If this is an instantiation record, walk through all the instantiation 760 // points. 761 FileID FID; 762 SourceLocation Loc; 763 do { 764 Loc = E->getInstantiation().getSpellingLoc(); 765 766 FID = getFileID(Loc); 767 E = &getSLocEntry(FID); 768 Offset += Loc.getOffset()-E->getOffset(); 769 } while (!Loc.isFileID()); 770 771 return std::make_pair(FID, Offset); 772} 773 774/// getImmediateSpellingLoc - Given a SourceLocation object, return the 775/// spelling location referenced by the ID. This is the first level down 776/// towards the place where the characters that make up the lexed token can be 777/// found. This should not generally be used by clients. 778SourceLocation SourceManager::getImmediateSpellingLoc(SourceLocation Loc) const{ 779 if (Loc.isFileID()) return Loc; 780 std::pair<FileID, unsigned> LocInfo = getDecomposedLoc(Loc); 781 Loc = getSLocEntry(LocInfo.first).getInstantiation().getSpellingLoc(); 782 return Loc.getFileLocWithOffset(LocInfo.second); 783} 784 785 786/// getImmediateInstantiationRange - Loc is required to be an instantiation 787/// location. Return the start/end of the instantiation information. 788std::pair<SourceLocation,SourceLocation> 789SourceManager::getImmediateInstantiationRange(SourceLocation Loc) const { 790 assert(Loc.isMacroID() && "Not an instantiation loc!"); 791 const InstantiationInfo &II = getSLocEntry(getFileID(Loc)).getInstantiation(); 792 return II.getInstantiationLocRange(); 793} 794 795/// getInstantiationRange - Given a SourceLocation object, return the 796/// range of tokens covered by the instantiation in the ultimate file. 797std::pair<SourceLocation,SourceLocation> 798SourceManager::getInstantiationRange(SourceLocation Loc) const { 799 if (Loc.isFileID()) return std::make_pair(Loc, Loc); 800 801 std::pair<SourceLocation,SourceLocation> Res = 802 getImmediateInstantiationRange(Loc); 803 804 // Fully resolve the start and end locations to their ultimate instantiation 805 // points. 806 while (!Res.first.isFileID()) 807 Res.first = getImmediateInstantiationRange(Res.first).first; 808 while (!Res.second.isFileID()) 809 Res.second = getImmediateInstantiationRange(Res.second).second; 810 return Res; 811} 812 813 814 815//===----------------------------------------------------------------------===// 816// Queries about the code at a SourceLocation. 817//===----------------------------------------------------------------------===// 818 819/// getCharacterData - Return a pointer to the start of the specified location 820/// in the appropriate MemoryBuffer. 821const char *SourceManager::getCharacterData(SourceLocation SL, 822 bool *Invalid) const { 823 // Note that this is a hot function in the getSpelling() path, which is 824 // heavily used by -E mode. 825 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(SL); 826 827 // Note that calling 'getBuffer()' may lazily page in a source file. 828 bool CharDataInvalid = false; 829 const SLocEntry &Entry = getSLocEntry(LocInfo.first, &CharDataInvalid); 830 if (CharDataInvalid || !Entry.isFile()) { 831 if (Invalid) 832 *Invalid = true; 833 834 return "<<<<INVALID BUFFER>>>>"; 835 } 836 const llvm::MemoryBuffer *Buffer 837 = Entry.getFile().getContentCache() 838 ->getBuffer(Diag, *this, SourceLocation(), &CharDataInvalid); 839 if (Invalid) 840 *Invalid = CharDataInvalid; 841 return Buffer->getBufferStart() + (CharDataInvalid? 0 : LocInfo.second); 842} 843 844 845/// getColumnNumber - Return the column # for the specified file position. 846/// this is significantly cheaper to compute than the line number. 847unsigned SourceManager::getColumnNumber(FileID FID, unsigned FilePos, 848 bool *Invalid) const { 849 bool MyInvalid = false; 850 const char *Buf = getBuffer(FID, &MyInvalid)->getBufferStart(); 851 if (Invalid) 852 *Invalid = MyInvalid; 853 854 if (MyInvalid) 855 return 1; 856 857 unsigned LineStart = FilePos; 858 while (LineStart && Buf[LineStart-1] != '\n' && Buf[LineStart-1] != '\r') 859 --LineStart; 860 return FilePos-LineStart+1; 861} 862 863// isInvalid - Return the result of calling loc.isInvalid(), and 864// if Invalid is not null, set its value to same. 865static bool isInvalid(SourceLocation Loc, bool *Invalid) { 866 bool MyInvalid = Loc.isInvalid(); 867 if (Invalid) 868 *Invalid = MyInvalid; 869 return MyInvalid; 870} 871 872unsigned SourceManager::getSpellingColumnNumber(SourceLocation Loc, 873 bool *Invalid) const { 874 if (isInvalid(Loc, Invalid)) return 0; 875 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(Loc); 876 return getColumnNumber(LocInfo.first, LocInfo.second, Invalid); 877} 878 879unsigned SourceManager::getInstantiationColumnNumber(SourceLocation Loc, 880 bool *Invalid) const { 881 if (isInvalid(Loc, Invalid)) return 0; 882 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 883 return getColumnNumber(LocInfo.first, LocInfo.second, Invalid); 884} 885 886unsigned SourceManager::getPresumedColumnNumber(SourceLocation Loc, 887 bool *Invalid) const { 888 if (isInvalid(Loc, Invalid)) return 0; 889 return getPresumedLoc(Loc).getColumn(); 890} 891 892static LLVM_ATTRIBUTE_NOINLINE void 893ComputeLineNumbers(Diagnostic &Diag, ContentCache *FI, 894 llvm::BumpPtrAllocator &Alloc, 895 const SourceManager &SM, bool &Invalid); 896static void ComputeLineNumbers(Diagnostic &Diag, ContentCache *FI, 897 llvm::BumpPtrAllocator &Alloc, 898 const SourceManager &SM, bool &Invalid) { 899 // Note that calling 'getBuffer()' may lazily page in the file. 900 const MemoryBuffer *Buffer = FI->getBuffer(Diag, SM, SourceLocation(), 901 &Invalid); 902 if (Invalid) 903 return; 904 905 // Find the file offsets of all of the *physical* source lines. This does 906 // not look at trigraphs, escaped newlines, or anything else tricky. 907 std::vector<unsigned> LineOffsets; 908 909 // Line #1 starts at char 0. 910 LineOffsets.push_back(0); 911 912 const unsigned char *Buf = (const unsigned char *)Buffer->getBufferStart(); 913 const unsigned char *End = (const unsigned char *)Buffer->getBufferEnd(); 914 unsigned Offs = 0; 915 while (1) { 916 // Skip over the contents of the line. 917 // TODO: Vectorize this? This is very performance sensitive for programs 918 // with lots of diagnostics and in -E mode. 919 const unsigned char *NextBuf = (const unsigned char *)Buf; 920 while (*NextBuf != '\n' && *NextBuf != '\r' && *NextBuf != '\0') 921 ++NextBuf; 922 Offs += NextBuf-Buf; 923 Buf = NextBuf; 924 925 if (Buf[0] == '\n' || Buf[0] == '\r') { 926 // If this is \n\r or \r\n, skip both characters. 927 if ((Buf[1] == '\n' || Buf[1] == '\r') && Buf[0] != Buf[1]) 928 ++Offs, ++Buf; 929 ++Offs, ++Buf; 930 LineOffsets.push_back(Offs); 931 } else { 932 // Otherwise, this is a null. If end of file, exit. 933 if (Buf == End) break; 934 // Otherwise, skip the null. 935 ++Offs, ++Buf; 936 } 937 } 938 939 // Copy the offsets into the FileInfo structure. 940 FI->NumLines = LineOffsets.size(); 941 FI->SourceLineCache = Alloc.Allocate<unsigned>(LineOffsets.size()); 942 std::copy(LineOffsets.begin(), LineOffsets.end(), FI->SourceLineCache); 943} 944 945/// getLineNumber - Given a SourceLocation, return the spelling line number 946/// for the position indicated. This requires building and caching a table of 947/// line offsets for the MemoryBuffer, so this is not cheap: use only when 948/// about to emit a diagnostic. 949unsigned SourceManager::getLineNumber(FileID FID, unsigned FilePos, 950 bool *Invalid) const { 951 ContentCache *Content; 952 if (LastLineNoFileIDQuery == FID) 953 Content = LastLineNoContentCache; 954 else { 955 bool MyInvalid = false; 956 const SLocEntry &Entry = getSLocEntry(FID, &MyInvalid); 957 if (MyInvalid || !Entry.isFile()) { 958 if (Invalid) 959 *Invalid = true; 960 return 1; 961 } 962 963 Content = const_cast<ContentCache*>(Entry.getFile().getContentCache()); 964 } 965 966 // If this is the first use of line information for this buffer, compute the 967 /// SourceLineCache for it on demand. 968 if (Content->SourceLineCache == 0) { 969 bool MyInvalid = false; 970 ComputeLineNumbers(Diag, Content, ContentCacheAlloc, *this, MyInvalid); 971 if (Invalid) 972 *Invalid = MyInvalid; 973 if (MyInvalid) 974 return 1; 975 } else if (Invalid) 976 *Invalid = false; 977 978 // Okay, we know we have a line number table. Do a binary search to find the 979 // line number that this character position lands on. 980 unsigned *SourceLineCache = Content->SourceLineCache; 981 unsigned *SourceLineCacheStart = SourceLineCache; 982 unsigned *SourceLineCacheEnd = SourceLineCache + Content->NumLines; 983 984 unsigned QueriedFilePos = FilePos+1; 985 986 // FIXME: I would like to be convinced that this code is worth being as 987 // complicated as it is, binary search isn't that slow. 988 // 989 // If it is worth being optimized, then in my opinion it could be more 990 // performant, simpler, and more obviously correct by just "galloping" outward 991 // from the queried file position. In fact, this could be incorporated into a 992 // generic algorithm such as lower_bound_with_hint. 993 // 994 // If someone gives me a test case where this matters, and I will do it! - DWD 995 996 // If the previous query was to the same file, we know both the file pos from 997 // that query and the line number returned. This allows us to narrow the 998 // search space from the entire file to something near the match. 999 if (LastLineNoFileIDQuery == FID) { 1000 if (QueriedFilePos >= LastLineNoFilePos) { 1001 // FIXME: Potential overflow? 1002 SourceLineCache = SourceLineCache+LastLineNoResult-1; 1003 1004 // The query is likely to be nearby the previous one. Here we check to 1005 // see if it is within 5, 10 or 20 lines. It can be far away in cases 1006 // where big comment blocks and vertical whitespace eat up lines but 1007 // contribute no tokens. 1008 if (SourceLineCache+5 < SourceLineCacheEnd) { 1009 if (SourceLineCache[5] > QueriedFilePos) 1010 SourceLineCacheEnd = SourceLineCache+5; 1011 else if (SourceLineCache+10 < SourceLineCacheEnd) { 1012 if (SourceLineCache[10] > QueriedFilePos) 1013 SourceLineCacheEnd = SourceLineCache+10; 1014 else if (SourceLineCache+20 < SourceLineCacheEnd) { 1015 if (SourceLineCache[20] > QueriedFilePos) 1016 SourceLineCacheEnd = SourceLineCache+20; 1017 } 1018 } 1019 } 1020 } else { 1021 if (LastLineNoResult < Content->NumLines) 1022 SourceLineCacheEnd = SourceLineCache+LastLineNoResult+1; 1023 } 1024 } 1025 1026 // If the spread is large, do a "radix" test as our initial guess, based on 1027 // the assumption that lines average to approximately the same length. 1028 // NOTE: This is currently disabled, as it does not appear to be profitable in 1029 // initial measurements. 1030 if (0 && SourceLineCacheEnd-SourceLineCache > 20) { 1031 unsigned FileLen = Content->SourceLineCache[Content->NumLines-1]; 1032 1033 // Take a stab at guessing where it is. 1034 unsigned ApproxPos = Content->NumLines*QueriedFilePos / FileLen; 1035 1036 // Check for -10 and +10 lines. 1037 unsigned LowerBound = std::max(int(ApproxPos-10), 0); 1038 unsigned UpperBound = std::min(ApproxPos+10, FileLen); 1039 1040 // If the computed lower bound is less than the query location, move it in. 1041 if (SourceLineCache < SourceLineCacheStart+LowerBound && 1042 SourceLineCacheStart[LowerBound] < QueriedFilePos) 1043 SourceLineCache = SourceLineCacheStart+LowerBound; 1044 1045 // If the computed upper bound is greater than the query location, move it. 1046 if (SourceLineCacheEnd > SourceLineCacheStart+UpperBound && 1047 SourceLineCacheStart[UpperBound] >= QueriedFilePos) 1048 SourceLineCacheEnd = SourceLineCacheStart+UpperBound; 1049 } 1050 1051 unsigned *Pos 1052 = std::lower_bound(SourceLineCache, SourceLineCacheEnd, QueriedFilePos); 1053 unsigned LineNo = Pos-SourceLineCacheStart; 1054 1055 LastLineNoFileIDQuery = FID; 1056 LastLineNoContentCache = Content; 1057 LastLineNoFilePos = QueriedFilePos; 1058 LastLineNoResult = LineNo; 1059 return LineNo; 1060} 1061 1062unsigned SourceManager::getSpellingLineNumber(SourceLocation Loc, 1063 bool *Invalid) const { 1064 if (isInvalid(Loc, Invalid)) return 0; 1065 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(Loc); 1066 return getLineNumber(LocInfo.first, LocInfo.second); 1067} 1068unsigned SourceManager::getInstantiationLineNumber(SourceLocation Loc, 1069 bool *Invalid) const { 1070 if (isInvalid(Loc, Invalid)) return 0; 1071 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 1072 return getLineNumber(LocInfo.first, LocInfo.second); 1073} 1074unsigned SourceManager::getPresumedLineNumber(SourceLocation Loc, 1075 bool *Invalid) const { 1076 if (isInvalid(Loc, Invalid)) return 0; 1077 return getPresumedLoc(Loc).getLine(); 1078} 1079 1080/// getFileCharacteristic - return the file characteristic of the specified 1081/// source location, indicating whether this is a normal file, a system 1082/// header, or an "implicit extern C" system header. 1083/// 1084/// This state can be modified with flags on GNU linemarker directives like: 1085/// # 4 "foo.h" 3 1086/// which changes all source locations in the current file after that to be 1087/// considered to be from a system header. 1088SrcMgr::CharacteristicKind 1089SourceManager::getFileCharacteristic(SourceLocation Loc) const { 1090 assert(!Loc.isInvalid() && "Can't get file characteristic of invalid loc!"); 1091 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 1092 bool Invalid = false; 1093 const SLocEntry &SEntry = getSLocEntry(LocInfo.first, &Invalid); 1094 if (Invalid || !SEntry.isFile()) 1095 return C_User; 1096 1097 const SrcMgr::FileInfo &FI = SEntry.getFile(); 1098 1099 // If there are no #line directives in this file, just return the whole-file 1100 // state. 1101 if (!FI.hasLineDirectives()) 1102 return FI.getFileCharacteristic(); 1103 1104 assert(LineTable && "Can't have linetable entries without a LineTable!"); 1105 // See if there is a #line directive before the location. 1106 const LineEntry *Entry = 1107 LineTable->FindNearestLineEntry(LocInfo.first.ID, LocInfo.second); 1108 1109 // If this is before the first line marker, use the file characteristic. 1110 if (!Entry) 1111 return FI.getFileCharacteristic(); 1112 1113 return Entry->FileKind; 1114} 1115 1116/// Return the filename or buffer identifier of the buffer the location is in. 1117/// Note that this name does not respect #line directives. Use getPresumedLoc 1118/// for normal clients. 1119const char *SourceManager::getBufferName(SourceLocation Loc, 1120 bool *Invalid) const { 1121 if (isInvalid(Loc, Invalid)) return "<invalid loc>"; 1122 1123 return getBuffer(getFileID(Loc), Invalid)->getBufferIdentifier(); 1124} 1125 1126 1127/// getPresumedLoc - This method returns the "presumed" location of a 1128/// SourceLocation specifies. A "presumed location" can be modified by #line 1129/// or GNU line marker directives. This provides a view on the data that a 1130/// user should see in diagnostics, for example. 1131/// 1132/// Note that a presumed location is always given as the instantiation point 1133/// of an instantiation location, not at the spelling location. 1134PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc) const { 1135 if (Loc.isInvalid()) return PresumedLoc(); 1136 1137 // Presumed locations are always for instantiation points. 1138 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 1139 1140 bool Invalid = false; 1141 const SLocEntry &Entry = getSLocEntry(LocInfo.first, &Invalid); 1142 if (Invalid || !Entry.isFile()) 1143 return PresumedLoc(); 1144 1145 const SrcMgr::FileInfo &FI = Entry.getFile(); 1146 const SrcMgr::ContentCache *C = FI.getContentCache(); 1147 1148 // To get the source name, first consult the FileEntry (if one exists) 1149 // before the MemBuffer as this will avoid unnecessarily paging in the 1150 // MemBuffer. 1151 const char *Filename; 1152 if (C->OrigEntry) 1153 Filename = C->OrigEntry->getName(); 1154 else 1155 Filename = C->getBuffer(Diag, *this)->getBufferIdentifier(); 1156 1157 unsigned LineNo = getLineNumber(LocInfo.first, LocInfo.second, &Invalid); 1158 if (Invalid) 1159 return PresumedLoc(); 1160 unsigned ColNo = getColumnNumber(LocInfo.first, LocInfo.second, &Invalid); 1161 if (Invalid) 1162 return PresumedLoc(); 1163 1164 SourceLocation IncludeLoc = FI.getIncludeLoc(); 1165 1166 // If we have #line directives in this file, update and overwrite the physical 1167 // location info if appropriate. 1168 if (FI.hasLineDirectives()) { 1169 assert(LineTable && "Can't have linetable entries without a LineTable!"); 1170 // See if there is a #line directive before this. If so, get it. 1171 if (const LineEntry *Entry = 1172 LineTable->FindNearestLineEntry(LocInfo.first.ID, LocInfo.second)) { 1173 // If the LineEntry indicates a filename, use it. 1174 if (Entry->FilenameID != -1) 1175 Filename = LineTable->getFilename(Entry->FilenameID); 1176 1177 // Use the line number specified by the LineEntry. This line number may 1178 // be multiple lines down from the line entry. Add the difference in 1179 // physical line numbers from the query point and the line marker to the 1180 // total. 1181 unsigned MarkerLineNo = getLineNumber(LocInfo.first, Entry->FileOffset); 1182 LineNo = Entry->LineNo + (LineNo-MarkerLineNo-1); 1183 1184 // Note that column numbers are not molested by line markers. 1185 1186 // Handle virtual #include manipulation. 1187 if (Entry->IncludeOffset) { 1188 IncludeLoc = getLocForStartOfFile(LocInfo.first); 1189 IncludeLoc = IncludeLoc.getFileLocWithOffset(Entry->IncludeOffset); 1190 } 1191 } 1192 } 1193 1194 return PresumedLoc(Filename, LineNo, ColNo, IncludeLoc); 1195} 1196 1197//===----------------------------------------------------------------------===// 1198// Other miscellaneous methods. 1199//===----------------------------------------------------------------------===// 1200 1201/// \brief Retrieve the inode for the given file entry, if possible. 1202/// 1203/// This routine involves a system call, and therefore should only be used 1204/// in non-performance-critical code. 1205static llvm::Optional<ino_t> getActualFileInode(const FileEntry *File) { 1206 if (!File) 1207 return llvm::Optional<ino_t>(); 1208 1209 struct stat StatBuf; 1210 if (::stat(File->getName(), &StatBuf)) 1211 return llvm::Optional<ino_t>(); 1212 1213 return StatBuf.st_ino; 1214} 1215 1216/// \brief Get the source location for the given file:line:col triplet. 1217/// 1218/// If the source file is included multiple times, the source location will 1219/// be based upon the first inclusion. 1220SourceLocation SourceManager::getLocation(const FileEntry *SourceFile, 1221 unsigned Line, unsigned Col) { 1222 assert(SourceFile && "Null source file!"); 1223 assert(Line && Col && "Line and column should start from 1!"); 1224 1225 // Find the first file ID that corresponds to the given file. 1226 FileID FirstFID; 1227 1228 // First, check the main file ID, since it is common to look for a 1229 // location in the main file. 1230 llvm::Optional<ino_t> SourceFileInode; 1231 llvm::Optional<llvm::StringRef> SourceFileName; 1232 if (!MainFileID.isInvalid()) { 1233 bool Invalid = false; 1234 const SLocEntry &MainSLoc = getSLocEntry(MainFileID, &Invalid); 1235 if (Invalid) 1236 return SourceLocation(); 1237 1238 if (MainSLoc.isFile()) { 1239 const ContentCache *MainContentCache 1240 = MainSLoc.getFile().getContentCache(); 1241 if (!MainContentCache) { 1242 // Can't do anything 1243 } else if (MainContentCache->OrigEntry == SourceFile) { 1244 FirstFID = MainFileID; 1245 } else { 1246 // Fall back: check whether we have the same base name and inode 1247 // as the main file. 1248 const FileEntry *MainFile = MainContentCache->OrigEntry; 1249 SourceFileName = llvm::sys::path::filename(SourceFile->getName()); 1250 if (*SourceFileName == llvm::sys::path::filename(MainFile->getName())) { 1251 SourceFileInode = getActualFileInode(SourceFile); 1252 if (SourceFileInode) { 1253 if (llvm::Optional<ino_t> MainFileInode 1254 = getActualFileInode(MainFile)) { 1255 if (*SourceFileInode == *MainFileInode) { 1256 FirstFID = MainFileID; 1257 SourceFile = MainFile; 1258 } 1259 } 1260 } 1261 } 1262 } 1263 } 1264 } 1265 1266 if (FirstFID.isInvalid()) { 1267 // The location we're looking for isn't in the main file; look 1268 // through all of the source locations. 1269 for (unsigned I = 0, N = sloc_entry_size(); I != N; ++I) { 1270 bool Invalid = false; 1271 const SLocEntry &SLoc = getSLocEntry(I, &Invalid); 1272 if (Invalid) 1273 return SourceLocation(); 1274 1275 if (SLoc.isFile() && 1276 SLoc.getFile().getContentCache() && 1277 SLoc.getFile().getContentCache()->OrigEntry == SourceFile) { 1278 FirstFID = FileID::get(I); 1279 break; 1280 } 1281 } 1282 } 1283 1284 // If we haven't found what we want yet, try again, but this time stat() 1285 // each of the files in case the files have changed since we originally 1286 // parsed the file. 1287 if (FirstFID.isInvalid() && 1288 (SourceFileName || 1289 (SourceFileName = llvm::sys::path::filename(SourceFile->getName()))) && 1290 (SourceFileInode || 1291 (SourceFileInode = getActualFileInode(SourceFile)))) { 1292 bool Invalid = false; 1293 for (unsigned I = 0, N = sloc_entry_size(); I != N; ++I) { 1294 const SLocEntry &SLoc = getSLocEntry(I, &Invalid); 1295 if (Invalid) 1296 return SourceLocation(); 1297 1298 if (SLoc.isFile()) { 1299 const ContentCache *FileContentCache 1300 = SLoc.getFile().getContentCache(); 1301 const FileEntry *Entry =FileContentCache? FileContentCache->OrigEntry : 0; 1302 if (Entry && 1303 *SourceFileName == llvm::sys::path::filename(Entry->getName())) { 1304 if (llvm::Optional<ino_t> EntryInode = getActualFileInode(Entry)) { 1305 if (*SourceFileInode == *EntryInode) { 1306 FirstFID = FileID::get(I); 1307 SourceFile = Entry; 1308 break; 1309 } 1310 } 1311 } 1312 } 1313 } 1314 } 1315 1316 if (FirstFID.isInvalid()) 1317 return SourceLocation(); 1318 1319 if (Line == 1 && Col == 1) 1320 return getLocForStartOfFile(FirstFID); 1321 1322 ContentCache *Content 1323 = const_cast<ContentCache *>(getOrCreateContentCache(SourceFile)); 1324 if (!Content) 1325 return SourceLocation(); 1326 1327 // If this is the first use of line information for this buffer, compute the 1328 /// SourceLineCache for it on demand. 1329 if (Content->SourceLineCache == 0) { 1330 bool MyInvalid = false; 1331 ComputeLineNumbers(Diag, Content, ContentCacheAlloc, *this, MyInvalid); 1332 if (MyInvalid) 1333 return SourceLocation(); 1334 } 1335 1336 if (Line > Content->NumLines) { 1337 unsigned Size = Content->getBuffer(Diag, *this)->getBufferSize(); 1338 if (Size > 0) 1339 --Size; 1340 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(Size); 1341 } 1342 1343 unsigned FilePos = Content->SourceLineCache[Line - 1]; 1344 const char *Buf = Content->getBuffer(Diag, *this)->getBufferStart() + FilePos; 1345 unsigned BufLength = Content->getBuffer(Diag, *this)->getBufferEnd() - Buf; 1346 unsigned i = 0; 1347 1348 // Check that the given column is valid. 1349 while (i < BufLength-1 && i < Col-1 && Buf[i] != '\n' && Buf[i] != '\r') 1350 ++i; 1351 if (i < Col-1) 1352 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(FilePos + i); 1353 1354 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(FilePos + Col - 1); 1355} 1356 1357/// Given a decomposed source location, move it up the include/instantiation 1358/// stack to the parent source location. If this is possible, return the 1359/// decomposed version of the parent in Loc and return false. If Loc is the 1360/// top-level entry, return true and don't modify it. 1361static bool MoveUpIncludeHierarchy(std::pair<FileID, unsigned> &Loc, 1362 const SourceManager &SM) { 1363 SourceLocation UpperLoc; 1364 const SrcMgr::SLocEntry &Entry = SM.getSLocEntry(Loc.first); 1365 if (Entry.isInstantiation()) 1366 UpperLoc = Entry.getInstantiation().getInstantiationLocStart(); 1367 else 1368 UpperLoc = Entry.getFile().getIncludeLoc(); 1369 1370 if (UpperLoc.isInvalid()) 1371 return true; // We reached the top. 1372 1373 Loc = SM.getDecomposedLoc(UpperLoc); 1374 return false; 1375} 1376 1377 1378/// \brief Determines the order of 2 source locations in the translation unit. 1379/// 1380/// \returns true if LHS source location comes before RHS, false otherwise. 1381bool SourceManager::isBeforeInTranslationUnit(SourceLocation LHS, 1382 SourceLocation RHS) const { 1383 assert(LHS.isValid() && RHS.isValid() && "Passed invalid source location!"); 1384 if (LHS == RHS) 1385 return false; 1386 1387 // If both locations are macro instantiations, the order of their offsets 1388 // reflect the order that the tokens, pointed to by these locations, were 1389 // instantiated (during parsing each token that is instantiated by a macro, 1390 // expands the SLocEntries). 1391 if (LHS.isMacroID() && RHS.isMacroID()) 1392 return LHS.getOffset() < RHS.getOffset(); 1393 1394 std::pair<FileID, unsigned> LOffs = getDecomposedLoc(LHS); 1395 std::pair<FileID, unsigned> ROffs = getDecomposedLoc(RHS); 1396 1397 // If the source locations are in the same file, just compare offsets. 1398 if (LOffs.first == ROffs.first) 1399 return LOffs.second < ROffs.second; 1400 1401 // If we are comparing a source location with multiple locations in the same 1402 // file, we get a big win by caching the result. 1403 if (IsBeforeInTUCache.isCacheValid(LOffs.first, ROffs.first)) 1404 return IsBeforeInTUCache.getCachedResult(LOffs.second, ROffs.second); 1405 1406 // Okay, we missed in the cache, start updating the cache for this query. 1407 IsBeforeInTUCache.setQueryFIDs(LOffs.first, ROffs.first); 1408 1409 // "Traverse" the include/instantiation stacks of both locations and try to 1410 // find a common "ancestor". FileIDs build a tree-like structure that 1411 // reflects the #include hierarchy, and this algorithm needs to find the 1412 // nearest common ancestor between the two locations. For example, if you 1413 // have a.c that includes b.h and c.h, and are comparing a location in b.h to 1414 // a location in c.h, we need to find that their nearest common ancestor is 1415 // a.c, and compare the locations of the two #includes to find their relative 1416 // ordering. 1417 // 1418 // SourceManager assigns FileIDs in order of parsing. This means that an 1419 // includee always has a larger FileID than an includer. While you might 1420 // think that we could just compare the FileID's here, that doesn't work to 1421 // compare a point at the end of a.c with a point within c.h. Though c.h has 1422 // a larger FileID, we have to compare the include point of c.h to the 1423 // location in a.c. 1424 // 1425 // Despite not being able to directly compare FileID's, we can tell that a 1426 // larger FileID is necessarily more deeply nested than a lower one and use 1427 // this information to walk up the tree to the nearest common ancestor. 1428 do { 1429 // If LOffs is larger than ROffs, then LOffs must be more deeply nested than 1430 // ROffs, walk up the #include chain. 1431 if (LOffs.first.ID > ROffs.first.ID) { 1432 if (MoveUpIncludeHierarchy(LOffs, *this)) 1433 break; // We reached the top. 1434 1435 } else { 1436 // Otherwise, ROffs is larger than LOffs, so ROffs must be more deeply 1437 // nested than LOffs, walk up the #include chain. 1438 if (MoveUpIncludeHierarchy(ROffs, *this)) 1439 break; // We reached the top. 1440 } 1441 } while (LOffs.first != ROffs.first); 1442 1443 // If we exited because we found a nearest common ancestor, compare the 1444 // locations within the common file and cache them. 1445 if (LOffs.first == ROffs.first) { 1446 IsBeforeInTUCache.setCommonLoc(LOffs.first, LOffs.second, ROffs.second); 1447 return IsBeforeInTUCache.getCachedResult(LOffs.second, ROffs.second); 1448 } 1449 1450 // There is no common ancestor, most probably because one location is in the 1451 // predefines buffer or an AST file. 1452 // FIXME: We should rearrange the external interface so this simply never 1453 // happens; it can't conceptually happen. Also see PR5662. 1454 IsBeforeInTUCache.setQueryFIDs(FileID(), FileID()); // Don't try caching. 1455 1456 // Zip both entries up to the top level record. 1457 while (!MoveUpIncludeHierarchy(LOffs, *this)) /*empty*/; 1458 while (!MoveUpIncludeHierarchy(ROffs, *this)) /*empty*/; 1459 1460 // If exactly one location is a memory buffer, assume it precedes the other. 1461 1462 // Strip off macro instantation locations, going up to the top-level File 1463 // SLocEntry. 1464 bool LIsMB = getFileEntryForID(LOffs.first) == 0; 1465 bool RIsMB = getFileEntryForID(ROffs.first) == 0; 1466 if (LIsMB != RIsMB) 1467 return LIsMB; 1468 1469 // Otherwise, just assume FileIDs were created in order. 1470 return LOffs.first < ROffs.first; 1471} 1472 1473/// PrintStats - Print statistics to stderr. 1474/// 1475void SourceManager::PrintStats() const { 1476 llvm::errs() << "\n*** Source Manager Stats:\n"; 1477 llvm::errs() << FileInfos.size() << " files mapped, " << MemBufferInfos.size() 1478 << " mem buffers mapped.\n"; 1479 llvm::errs() << SLocEntryTable.size() << " SLocEntry's allocated, " 1480 << NextOffset << "B of Sloc address space used.\n"; 1481 1482 unsigned NumLineNumsComputed = 0; 1483 unsigned NumFileBytesMapped = 0; 1484 for (fileinfo_iterator I = fileinfo_begin(), E = fileinfo_end(); I != E; ++I){ 1485 NumLineNumsComputed += I->second->SourceLineCache != 0; 1486 NumFileBytesMapped += I->second->getSizeBytesMapped(); 1487 } 1488 1489 llvm::errs() << NumFileBytesMapped << " bytes of files mapped, " 1490 << NumLineNumsComputed << " files with line #'s computed.\n"; 1491 llvm::errs() << "FileID scans: " << NumLinearScans << " linear, " 1492 << NumBinaryProbes << " binary.\n"; 1493} 1494 1495ExternalSLocEntrySource::~ExternalSLocEntrySource() { } 1496