SourceManager.cpp revision 669a67760c601a20787d375eb73047763d5adaaa
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/Support/Compiler.h" 19#include "llvm/Support/MemoryBuffer.h" 20#include "llvm/Support/raw_ostream.h" 21#include "llvm/System/Path.h" 22#include <algorithm> 23#include <string> 24#include <cstring> 25 26using namespace clang; 27using namespace SrcMgr; 28using llvm::MemoryBuffer; 29 30//===----------------------------------------------------------------------===// 31// SourceManager Helper Classes 32//===----------------------------------------------------------------------===// 33 34ContentCache::~ContentCache() { 35 delete Buffer.getPointer(); 36} 37 38/// getSizeBytesMapped - Returns the number of bytes actually mapped for 39/// this ContentCache. This can be 0 if the MemBuffer was not actually 40/// instantiated. 41unsigned ContentCache::getSizeBytesMapped() const { 42 return Buffer.getPointer() ? Buffer.getPointer()->getBufferSize() : 0; 43} 44 45/// getSize - Returns the size of the content encapsulated by this ContentCache. 46/// This can be the size of the source file or the size of an arbitrary 47/// scratch buffer. If the ContentCache encapsulates a source file, that 48/// file is not lazily brought in from disk to satisfy this query. 49unsigned ContentCache::getSize() const { 50 return Buffer.getPointer() ? (unsigned) Buffer.getPointer()->getBufferSize() 51 : (unsigned) Entry->getSize(); 52} 53 54void ContentCache::replaceBuffer(const llvm::MemoryBuffer *B) { 55 assert(B != Buffer.getPointer()); 56 57 delete Buffer.getPointer(); 58 Buffer.setPointer(B); 59 Buffer.setInt(false); 60} 61 62const llvm::MemoryBuffer *ContentCache::getBuffer(Diagnostic &Diag, 63 const SourceManager &SM, 64 SourceLocation Loc, 65 bool *Invalid) const { 66 if (Invalid) 67 *Invalid = false; 68 69 // Lazily create the Buffer for ContentCaches that wrap files. 70 if (!Buffer.getPointer() && Entry) { 71 std::string ErrorStr; 72 struct stat FileInfo; 73 Buffer.setPointer(MemoryBuffer::getFile(Entry->getName(), &ErrorStr, 74 Entry->getSize(), &FileInfo)); 75 Buffer.setInt(false); 76 77 // If we were unable to open the file, then we are in an inconsistent 78 // situation where the content cache referenced a file which no longer 79 // exists. Most likely, we were using a stat cache with an invalid entry but 80 // the file could also have been removed during processing. Since we can't 81 // really deal with this situation, just create an empty buffer. 82 // 83 // FIXME: This is definitely not ideal, but our immediate clients can't 84 // currently handle returning a null entry here. Ideally we should detect 85 // that we are in an inconsistent situation and error out as quickly as 86 // possible. 87 if (!Buffer.getPointer()) { 88 const llvm::StringRef FillStr("<<<MISSING SOURCE FILE>>>\n"); 89 Buffer.setPointer(MemoryBuffer::getNewMemBuffer(Entry->getSize(), 90 "<invalid>")); 91 char *Ptr = const_cast<char*>(Buffer.getPointer()->getBufferStart()); 92 for (unsigned i = 0, e = Entry->getSize(); i != e; ++i) 93 Ptr[i] = FillStr[i % FillStr.size()]; 94 95 if (Diag.isDiagnosticInFlight()) 96 Diag.SetDelayedDiagnostic(diag::err_cannot_open_file, 97 Entry->getName(), ErrorStr); 98 else 99 Diag.Report(FullSourceLoc(Loc, SM), diag::err_cannot_open_file) 100 << Entry->getName() << ErrorStr; 101 102 Buffer.setInt(true); 103 104 // FIXME: This conditionalization is horrible, but we see spurious failures 105 // in the test suite due to this warning and no one has had time to hunt it 106 // down. So for now, we just don't emit this diagnostic on Win32, and hope 107 // nothing bad happens. 108 // 109 // PR6812. 110#if !defined(LLVM_ON_WIN32) 111 } else if (FileInfo.st_size != Entry->getSize() || 112 FileInfo.st_mtime != Entry->getModificationTime()) { 113 // Check that the file's size and modification time are the same 114 // as in the file entry (which may have come from a stat cache). 115 if (Diag.isDiagnosticInFlight()) 116 Diag.SetDelayedDiagnostic(diag::err_file_modified, 117 Entry->getName()); 118 else 119 Diag.Report(FullSourceLoc(Loc, SM), diag::err_file_modified) 120 << Entry->getName(); 121 122 Buffer.setInt(true); 123#endif 124 } 125 126 // If the buffer is valid, check to see if it has a UTF Byte Order Mark 127 // (BOM). We only support UTF-8 without a BOM right now. See 128 // http://en.wikipedia.org/wiki/Byte_order_mark for more information. 129 if (!Buffer.getInt()) { 130 llvm::StringRef BufStr = Buffer.getPointer()->getBuffer(); 131 const char *BOM = 0; 132 if (BufStr.startswith("\xFE\xBB\xBF")) 133 BOM = "UTF-8"; 134 else if (BufStr.startswith("\xFE\xFF")) 135 BOM = "UTF-16 (BE)"; 136 else if (BufStr.startswith("\xFF\xFE")) 137 BOM = "UTF-16 (LE)"; 138 else if (BufStr.startswith(llvm::StringRef("\x00\x00\xFE\xFF", 4))) 139 BOM = "UTF-32 (BE)"; 140 else if (BufStr.startswith(llvm::StringRef("\xFF\xFE\x00\x00", 4))) 141 BOM = "UTF-32 (LE)"; 142 else if (BufStr.startswith("\x2B\x2F\x76")) 143 BOM = "UTF-7"; 144 else if (BufStr.startswith("\xF7\x64\x4C")) 145 BOM = "UTF-1"; 146 else if (BufStr.startswith("\xDD\x73\x66\x73")) 147 BOM = "UTF-EBCDIC"; 148 else if (BufStr.startswith("\x0E\xFE\xFF")) 149 BOM = "SDSU"; 150 else if (BufStr.startswith("\xFB\xEE\x28")) 151 BOM = "BOCU-1"; 152 else if (BufStr.startswith("\x84\x31\x95\x33")) 153 BOM = "BOCU-1"; 154 155 if (BOM) { 156 Diag.Report(FullSourceLoc(Loc, SM), diag::err_unsupported_bom) 157 << BOM << Entry->getName(); 158 Buffer.setInt(1); 159 } 160 } 161 } 162 163 if (Invalid) 164 *Invalid = Buffer.getInt(); 165 166 return Buffer.getPointer(); 167} 168 169unsigned LineTableInfo::getLineTableFilenameID(const char *Ptr, unsigned Len) { 170 // Look up the filename in the string table, returning the pre-existing value 171 // if it exists. 172 llvm::StringMapEntry<unsigned> &Entry = 173 FilenameIDs.GetOrCreateValue(Ptr, Ptr+Len, ~0U); 174 if (Entry.getValue() != ~0U) 175 return Entry.getValue(); 176 177 // Otherwise, assign this the next available ID. 178 Entry.setValue(FilenamesByID.size()); 179 FilenamesByID.push_back(&Entry); 180 return FilenamesByID.size()-1; 181} 182 183/// AddLineNote - Add a line note to the line table that indicates that there 184/// is a #line at the specified FID/Offset location which changes the presumed 185/// location to LineNo/FilenameID. 186void LineTableInfo::AddLineNote(unsigned FID, unsigned Offset, 187 unsigned LineNo, int FilenameID) { 188 std::vector<LineEntry> &Entries = LineEntries[FID]; 189 190 assert((Entries.empty() || Entries.back().FileOffset < Offset) && 191 "Adding line entries out of order!"); 192 193 SrcMgr::CharacteristicKind Kind = SrcMgr::C_User; 194 unsigned IncludeOffset = 0; 195 196 if (!Entries.empty()) { 197 // If this is a '#line 4' after '#line 42 "foo.h"', make sure to remember 198 // that we are still in "foo.h". 199 if (FilenameID == -1) 200 FilenameID = Entries.back().FilenameID; 201 202 // If we are after a line marker that switched us to system header mode, or 203 // that set #include information, preserve it. 204 Kind = Entries.back().FileKind; 205 IncludeOffset = Entries.back().IncludeOffset; 206 } 207 208 Entries.push_back(LineEntry::get(Offset, LineNo, FilenameID, Kind, 209 IncludeOffset)); 210} 211 212/// AddLineNote This is the same as the previous version of AddLineNote, but is 213/// used for GNU line markers. If EntryExit is 0, then this doesn't change the 214/// presumed #include stack. If it is 1, this is a file entry, if it is 2 then 215/// this is a file exit. FileKind specifies whether this is a system header or 216/// extern C system header. 217void LineTableInfo::AddLineNote(unsigned FID, unsigned Offset, 218 unsigned LineNo, int FilenameID, 219 unsigned EntryExit, 220 SrcMgr::CharacteristicKind FileKind) { 221 assert(FilenameID != -1 && "Unspecified filename should use other accessor"); 222 223 std::vector<LineEntry> &Entries = LineEntries[FID]; 224 225 assert((Entries.empty() || Entries.back().FileOffset < Offset) && 226 "Adding line entries out of order!"); 227 228 unsigned IncludeOffset = 0; 229 if (EntryExit == 0) { // No #include stack change. 230 IncludeOffset = Entries.empty() ? 0 : Entries.back().IncludeOffset; 231 } else if (EntryExit == 1) { 232 IncludeOffset = Offset-1; 233 } else if (EntryExit == 2) { 234 assert(!Entries.empty() && Entries.back().IncludeOffset && 235 "PPDirectives should have caught case when popping empty include stack"); 236 237 // Get the include loc of the last entries' include loc as our include loc. 238 IncludeOffset = 0; 239 if (const LineEntry *PrevEntry = 240 FindNearestLineEntry(FID, Entries.back().IncludeOffset)) 241 IncludeOffset = PrevEntry->IncludeOffset; 242 } 243 244 Entries.push_back(LineEntry::get(Offset, LineNo, FilenameID, FileKind, 245 IncludeOffset)); 246} 247 248 249/// FindNearestLineEntry - Find the line entry nearest to FID that is before 250/// it. If there is no line entry before Offset in FID, return null. 251const LineEntry *LineTableInfo::FindNearestLineEntry(unsigned FID, 252 unsigned Offset) { 253 const std::vector<LineEntry> &Entries = LineEntries[FID]; 254 assert(!Entries.empty() && "No #line entries for this FID after all!"); 255 256 // It is very common for the query to be after the last #line, check this 257 // first. 258 if (Entries.back().FileOffset <= Offset) 259 return &Entries.back(); 260 261 // Do a binary search to find the maximal element that is still before Offset. 262 std::vector<LineEntry>::const_iterator I = 263 std::upper_bound(Entries.begin(), Entries.end(), Offset); 264 if (I == Entries.begin()) return 0; 265 return &*--I; 266} 267 268/// \brief Add a new line entry that has already been encoded into 269/// the internal representation of the line table. 270void LineTableInfo::AddEntry(unsigned FID, 271 const std::vector<LineEntry> &Entries) { 272 LineEntries[FID] = Entries; 273} 274 275/// getLineTableFilenameID - Return the uniqued ID for the specified filename. 276/// 277unsigned SourceManager::getLineTableFilenameID(const char *Ptr, unsigned Len) { 278 if (LineTable == 0) 279 LineTable = new LineTableInfo(); 280 return LineTable->getLineTableFilenameID(Ptr, Len); 281} 282 283 284/// AddLineNote - Add a line note to the line table for the FileID and offset 285/// specified by Loc. If FilenameID is -1, it is considered to be 286/// unspecified. 287void SourceManager::AddLineNote(SourceLocation Loc, unsigned LineNo, 288 int FilenameID) { 289 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 290 291 const SrcMgr::FileInfo &FileInfo = getSLocEntry(LocInfo.first).getFile(); 292 293 // Remember that this file has #line directives now if it doesn't already. 294 const_cast<SrcMgr::FileInfo&>(FileInfo).setHasLineDirectives(); 295 296 if (LineTable == 0) 297 LineTable = new LineTableInfo(); 298 LineTable->AddLineNote(LocInfo.first.ID, LocInfo.second, LineNo, FilenameID); 299} 300 301/// AddLineNote - Add a GNU line marker to the line table. 302void SourceManager::AddLineNote(SourceLocation Loc, unsigned LineNo, 303 int FilenameID, bool IsFileEntry, 304 bool IsFileExit, bool IsSystemHeader, 305 bool IsExternCHeader) { 306 // If there is no filename and no flags, this is treated just like a #line, 307 // which does not change the flags of the previous line marker. 308 if (FilenameID == -1) { 309 assert(!IsFileEntry && !IsFileExit && !IsSystemHeader && !IsExternCHeader && 310 "Can't set flags without setting the filename!"); 311 return AddLineNote(Loc, LineNo, FilenameID); 312 } 313 314 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 315 const SrcMgr::FileInfo &FileInfo = getSLocEntry(LocInfo.first).getFile(); 316 317 // Remember that this file has #line directives now if it doesn't already. 318 const_cast<SrcMgr::FileInfo&>(FileInfo).setHasLineDirectives(); 319 320 if (LineTable == 0) 321 LineTable = new LineTableInfo(); 322 323 SrcMgr::CharacteristicKind FileKind; 324 if (IsExternCHeader) 325 FileKind = SrcMgr::C_ExternCSystem; 326 else if (IsSystemHeader) 327 FileKind = SrcMgr::C_System; 328 else 329 FileKind = SrcMgr::C_User; 330 331 unsigned EntryExit = 0; 332 if (IsFileEntry) 333 EntryExit = 1; 334 else if (IsFileExit) 335 EntryExit = 2; 336 337 LineTable->AddLineNote(LocInfo.first.ID, LocInfo.second, LineNo, FilenameID, 338 EntryExit, FileKind); 339} 340 341LineTableInfo &SourceManager::getLineTable() { 342 if (LineTable == 0) 343 LineTable = new LineTableInfo(); 344 return *LineTable; 345} 346 347//===----------------------------------------------------------------------===// 348// Private 'Create' methods. 349//===----------------------------------------------------------------------===// 350 351SourceManager::~SourceManager() { 352 delete LineTable; 353 354 // Delete FileEntry objects corresponding to content caches. Since the actual 355 // content cache objects are bump pointer allocated, we just have to run the 356 // dtors, but we call the deallocate method for completeness. 357 for (unsigned i = 0, e = MemBufferInfos.size(); i != e; ++i) { 358 MemBufferInfos[i]->~ContentCache(); 359 ContentCacheAlloc.Deallocate(MemBufferInfos[i]); 360 } 361 for (llvm::DenseMap<const FileEntry*, SrcMgr::ContentCache*>::iterator 362 I = FileInfos.begin(), E = FileInfos.end(); I != E; ++I) { 363 I->second->~ContentCache(); 364 ContentCacheAlloc.Deallocate(I->second); 365 } 366} 367 368void SourceManager::clearIDTables() { 369 MainFileID = FileID(); 370 SLocEntryTable.clear(); 371 LastLineNoFileIDQuery = FileID(); 372 LastLineNoContentCache = 0; 373 LastFileIDLookup = FileID(); 374 375 if (LineTable) 376 LineTable->clear(); 377 378 // Use up FileID #0 as an invalid instantiation. 379 NextOffset = 0; 380 createInstantiationLoc(SourceLocation(),SourceLocation(),SourceLocation(), 1); 381} 382 383/// getOrCreateContentCache - Create or return a cached ContentCache for the 384/// specified file. 385const ContentCache * 386SourceManager::getOrCreateContentCache(const FileEntry *FileEnt) { 387 assert(FileEnt && "Didn't specify a file entry to use?"); 388 389 // Do we already have information about this file? 390 ContentCache *&Entry = FileInfos[FileEnt]; 391 if (Entry) return Entry; 392 393 // Nope, create a new Cache entry. Make sure it is at least 8-byte aligned 394 // so that FileInfo can use the low 3 bits of the pointer for its own 395 // nefarious purposes. 396 unsigned EntryAlign = llvm::AlignOf<ContentCache>::Alignment; 397 EntryAlign = std::max(8U, EntryAlign); 398 Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign); 399 new (Entry) ContentCache(FileEnt); 400 return Entry; 401} 402 403 404/// createMemBufferContentCache - Create a new ContentCache for the specified 405/// memory buffer. This does no caching. 406const ContentCache* 407SourceManager::createMemBufferContentCache(const MemoryBuffer *Buffer) { 408 // Add a new ContentCache to the MemBufferInfos list and return it. Make sure 409 // it is at least 8-byte aligned so that FileInfo can use the low 3 bits of 410 // the pointer for its own nefarious purposes. 411 unsigned EntryAlign = llvm::AlignOf<ContentCache>::Alignment; 412 EntryAlign = std::max(8U, EntryAlign); 413 ContentCache *Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign); 414 new (Entry) ContentCache(); 415 MemBufferInfos.push_back(Entry); 416 Entry->setBuffer(Buffer); 417 return Entry; 418} 419 420void SourceManager::PreallocateSLocEntries(ExternalSLocEntrySource *Source, 421 unsigned NumSLocEntries, 422 unsigned NextOffset) { 423 ExternalSLocEntries = Source; 424 this->NextOffset = NextOffset; 425 SLocEntryLoaded.resize(NumSLocEntries + 1); 426 SLocEntryLoaded[0] = true; 427 SLocEntryTable.resize(SLocEntryTable.size() + NumSLocEntries); 428} 429 430void SourceManager::ClearPreallocatedSLocEntries() { 431 unsigned I = 0; 432 for (unsigned N = SLocEntryLoaded.size(); I != N; ++I) 433 if (!SLocEntryLoaded[I]) 434 break; 435 436 // We've already loaded all preallocated source location entries. 437 if (I == SLocEntryLoaded.size()) 438 return; 439 440 // Remove everything from location I onward. 441 SLocEntryTable.resize(I); 442 SLocEntryLoaded.clear(); 443 ExternalSLocEntries = 0; 444} 445 446 447//===----------------------------------------------------------------------===// 448// Methods to create new FileID's and instantiations. 449//===----------------------------------------------------------------------===// 450 451/// createFileID - Create a new fileID for the specified ContentCache and 452/// include position. This works regardless of whether the ContentCache 453/// corresponds to a file or some other input source. 454FileID SourceManager::createFileID(const ContentCache *File, 455 SourceLocation IncludePos, 456 SrcMgr::CharacteristicKind FileCharacter, 457 unsigned PreallocatedID, 458 unsigned Offset) { 459 if (PreallocatedID) { 460 // If we're filling in a preallocated ID, just load in the file 461 // entry and return. 462 assert(PreallocatedID < SLocEntryLoaded.size() && 463 "Preallocate ID out-of-range"); 464 assert(!SLocEntryLoaded[PreallocatedID] && 465 "Source location entry already loaded"); 466 assert(Offset && "Preallocate source location cannot have zero offset"); 467 SLocEntryTable[PreallocatedID] 468 = SLocEntry::get(Offset, FileInfo::get(IncludePos, File, FileCharacter)); 469 SLocEntryLoaded[PreallocatedID] = true; 470 FileID FID = FileID::get(PreallocatedID); 471 return FID; 472 } 473 474 SLocEntryTable.push_back(SLocEntry::get(NextOffset, 475 FileInfo::get(IncludePos, File, 476 FileCharacter))); 477 unsigned FileSize = File->getSize(); 478 assert(NextOffset+FileSize+1 > NextOffset && "Ran out of source locations!"); 479 NextOffset += FileSize+1; 480 481 // Set LastFileIDLookup to the newly created file. The next getFileID call is 482 // almost guaranteed to be from that file. 483 FileID FID = FileID::get(SLocEntryTable.size()-1); 484 return LastFileIDLookup = FID; 485} 486 487/// createInstantiationLoc - Return a new SourceLocation that encodes the fact 488/// that a token from SpellingLoc should actually be referenced from 489/// InstantiationLoc. 490SourceLocation SourceManager::createInstantiationLoc(SourceLocation SpellingLoc, 491 SourceLocation ILocStart, 492 SourceLocation ILocEnd, 493 unsigned TokLength, 494 unsigned PreallocatedID, 495 unsigned Offset) { 496 InstantiationInfo II = InstantiationInfo::get(ILocStart,ILocEnd, SpellingLoc); 497 if (PreallocatedID) { 498 // If we're filling in a preallocated ID, just load in the 499 // instantiation entry and return. 500 assert(PreallocatedID < SLocEntryLoaded.size() && 501 "Preallocate ID out-of-range"); 502 assert(!SLocEntryLoaded[PreallocatedID] && 503 "Source location entry already loaded"); 504 assert(Offset && "Preallocate source location cannot have zero offset"); 505 SLocEntryTable[PreallocatedID] = SLocEntry::get(Offset, II); 506 SLocEntryLoaded[PreallocatedID] = true; 507 return SourceLocation::getMacroLoc(Offset); 508 } 509 SLocEntryTable.push_back(SLocEntry::get(NextOffset, II)); 510 assert(NextOffset+TokLength+1 > NextOffset && "Ran out of source locations!"); 511 NextOffset += TokLength+1; 512 return SourceLocation::getMacroLoc(NextOffset-(TokLength+1)); 513} 514 515const llvm::MemoryBuffer * 516SourceManager::getMemoryBufferForFile(const FileEntry *File, 517 bool *Invalid) { 518 const SrcMgr::ContentCache *IR = getOrCreateContentCache(File); 519 assert(IR && "getOrCreateContentCache() cannot return NULL"); 520 return IR->getBuffer(Diag, *this, SourceLocation(), Invalid); 521} 522 523bool SourceManager::overrideFileContents(const FileEntry *SourceFile, 524 const llvm::MemoryBuffer *Buffer) { 525 const SrcMgr::ContentCache *IR = getOrCreateContentCache(SourceFile); 526 if (IR == 0) 527 return true; 528 529 const_cast<SrcMgr::ContentCache *>(IR)->replaceBuffer(Buffer); 530 return false; 531} 532 533llvm::StringRef SourceManager::getBufferData(FileID FID, bool *Invalid) const { 534 bool MyInvalid = false; 535 const llvm::MemoryBuffer *Buf = getBuffer(FID, &MyInvalid); 536 if (Invalid) 537 *Invalid = MyInvalid; 538 539 if (MyInvalid) 540 return ""; 541 542 return Buf->getBuffer(); 543} 544 545//===----------------------------------------------------------------------===// 546// SourceLocation manipulation methods. 547//===----------------------------------------------------------------------===// 548 549/// getFileIDSlow - Return the FileID for a SourceLocation. This is a very hot 550/// method that is used for all SourceManager queries that start with a 551/// SourceLocation object. It is responsible for finding the entry in 552/// SLocEntryTable which contains the specified location. 553/// 554FileID SourceManager::getFileIDSlow(unsigned SLocOffset) const { 555 assert(SLocOffset && "Invalid FileID"); 556 557 // After the first and second level caches, I see two common sorts of 558 // behavior: 1) a lot of searched FileID's are "near" the cached file location 559 // or are "near" the cached instantiation location. 2) others are just 560 // completely random and may be a very long way away. 561 // 562 // To handle this, we do a linear search for up to 8 steps to catch #1 quickly 563 // then we fall back to a less cache efficient, but more scalable, binary 564 // search to find the location. 565 566 // See if this is near the file point - worst case we start scanning from the 567 // most newly created FileID. 568 std::vector<SrcMgr::SLocEntry>::const_iterator I; 569 570 if (SLocEntryTable[LastFileIDLookup.ID].getOffset() < SLocOffset) { 571 // Neither loc prunes our search. 572 I = SLocEntryTable.end(); 573 } else { 574 // Perhaps it is near the file point. 575 I = SLocEntryTable.begin()+LastFileIDLookup.ID; 576 } 577 578 // Find the FileID that contains this. "I" is an iterator that points to a 579 // FileID whose offset is known to be larger than SLocOffset. 580 unsigned NumProbes = 0; 581 while (1) { 582 --I; 583 if (ExternalSLocEntries) 584 getSLocEntry(FileID::get(I - SLocEntryTable.begin())); 585 if (I->getOffset() <= SLocOffset) { 586#if 0 587 printf("lin %d -> %d [%s] %d %d\n", SLocOffset, 588 I-SLocEntryTable.begin(), 589 I->isInstantiation() ? "inst" : "file", 590 LastFileIDLookup.ID, int(SLocEntryTable.end()-I)); 591#endif 592 FileID Res = FileID::get(I-SLocEntryTable.begin()); 593 594 // If this isn't an instantiation, remember it. We have good locality 595 // across FileID lookups. 596 if (!I->isInstantiation()) 597 LastFileIDLookup = Res; 598 NumLinearScans += NumProbes+1; 599 return Res; 600 } 601 if (++NumProbes == 8) 602 break; 603 } 604 605 // Convert "I" back into an index. We know that it is an entry whose index is 606 // larger than the offset we are looking for. 607 unsigned GreaterIndex = I-SLocEntryTable.begin(); 608 // LessIndex - This is the lower bound of the range that we're searching. 609 // We know that the offset corresponding to the FileID is is less than 610 // SLocOffset. 611 unsigned LessIndex = 0; 612 NumProbes = 0; 613 while (1) { 614 unsigned MiddleIndex = (GreaterIndex-LessIndex)/2+LessIndex; 615 unsigned MidOffset = getSLocEntry(FileID::get(MiddleIndex)).getOffset(); 616 617 ++NumProbes; 618 619 // If the offset of the midpoint is too large, chop the high side of the 620 // range to the midpoint. 621 if (MidOffset > SLocOffset) { 622 GreaterIndex = MiddleIndex; 623 continue; 624 } 625 626 // If the middle index contains the value, succeed and return. 627 if (isOffsetInFileID(FileID::get(MiddleIndex), SLocOffset)) { 628#if 0 629 printf("bin %d -> %d [%s] %d %d\n", SLocOffset, 630 I-SLocEntryTable.begin(), 631 I->isInstantiation() ? "inst" : "file", 632 LastFileIDLookup.ID, int(SLocEntryTable.end()-I)); 633#endif 634 FileID Res = FileID::get(MiddleIndex); 635 636 // If this isn't an instantiation, remember it. We have good locality 637 // across FileID lookups. 638 if (!I->isInstantiation()) 639 LastFileIDLookup = Res; 640 NumBinaryProbes += NumProbes; 641 return Res; 642 } 643 644 // Otherwise, move the low-side up to the middle index. 645 LessIndex = MiddleIndex; 646 } 647} 648 649SourceLocation SourceManager:: 650getInstantiationLocSlowCase(SourceLocation Loc) const { 651 do { 652 // Note: If Loc indicates an offset into a token that came from a macro 653 // expansion (e.g. the 5th character of the token) we do not want to add 654 // this offset when going to the instantiation location. The instatiation 655 // location is the macro invocation, which the offset has nothing to do 656 // with. This is unlike when we get the spelling loc, because the offset 657 // directly correspond to the token whose spelling we're inspecting. 658 Loc = getSLocEntry(getFileID(Loc)).getInstantiation() 659 .getInstantiationLocStart(); 660 } while (!Loc.isFileID()); 661 662 return Loc; 663} 664 665SourceLocation SourceManager::getSpellingLocSlowCase(SourceLocation Loc) const { 666 do { 667 std::pair<FileID, unsigned> LocInfo = getDecomposedLoc(Loc); 668 Loc = getSLocEntry(LocInfo.first).getInstantiation().getSpellingLoc(); 669 Loc = Loc.getFileLocWithOffset(LocInfo.second); 670 } while (!Loc.isFileID()); 671 return Loc; 672} 673 674 675std::pair<FileID, unsigned> 676SourceManager::getDecomposedInstantiationLocSlowCase(const SrcMgr::SLocEntry *E, 677 unsigned Offset) const { 678 // If this is an instantiation record, walk through all the instantiation 679 // points. 680 FileID FID; 681 SourceLocation Loc; 682 do { 683 Loc = E->getInstantiation().getInstantiationLocStart(); 684 685 FID = getFileID(Loc); 686 E = &getSLocEntry(FID); 687 Offset += Loc.getOffset()-E->getOffset(); 688 } while (!Loc.isFileID()); 689 690 return std::make_pair(FID, Offset); 691} 692 693std::pair<FileID, unsigned> 694SourceManager::getDecomposedSpellingLocSlowCase(const SrcMgr::SLocEntry *E, 695 unsigned Offset) const { 696 // If this is an instantiation record, walk through all the instantiation 697 // points. 698 FileID FID; 699 SourceLocation Loc; 700 do { 701 Loc = E->getInstantiation().getSpellingLoc(); 702 703 FID = getFileID(Loc); 704 E = &getSLocEntry(FID); 705 Offset += Loc.getOffset()-E->getOffset(); 706 } while (!Loc.isFileID()); 707 708 return std::make_pair(FID, Offset); 709} 710 711/// getImmediateSpellingLoc - Given a SourceLocation object, return the 712/// spelling location referenced by the ID. This is the first level down 713/// towards the place where the characters that make up the lexed token can be 714/// found. This should not generally be used by clients. 715SourceLocation SourceManager::getImmediateSpellingLoc(SourceLocation Loc) const{ 716 if (Loc.isFileID()) return Loc; 717 std::pair<FileID, unsigned> LocInfo = getDecomposedLoc(Loc); 718 Loc = getSLocEntry(LocInfo.first).getInstantiation().getSpellingLoc(); 719 return Loc.getFileLocWithOffset(LocInfo.second); 720} 721 722 723/// getImmediateInstantiationRange - Loc is required to be an instantiation 724/// location. Return the start/end of the instantiation information. 725std::pair<SourceLocation,SourceLocation> 726SourceManager::getImmediateInstantiationRange(SourceLocation Loc) const { 727 assert(Loc.isMacroID() && "Not an instantiation loc!"); 728 const InstantiationInfo &II = getSLocEntry(getFileID(Loc)).getInstantiation(); 729 return II.getInstantiationLocRange(); 730} 731 732/// getInstantiationRange - Given a SourceLocation object, return the 733/// range of tokens covered by the instantiation in the ultimate file. 734std::pair<SourceLocation,SourceLocation> 735SourceManager::getInstantiationRange(SourceLocation Loc) const { 736 if (Loc.isFileID()) return std::make_pair(Loc, Loc); 737 738 std::pair<SourceLocation,SourceLocation> Res = 739 getImmediateInstantiationRange(Loc); 740 741 // Fully resolve the start and end locations to their ultimate instantiation 742 // points. 743 while (!Res.first.isFileID()) 744 Res.first = getImmediateInstantiationRange(Res.first).first; 745 while (!Res.second.isFileID()) 746 Res.second = getImmediateInstantiationRange(Res.second).second; 747 return Res; 748} 749 750 751 752//===----------------------------------------------------------------------===// 753// Queries about the code at a SourceLocation. 754//===----------------------------------------------------------------------===// 755 756/// getCharacterData - Return a pointer to the start of the specified location 757/// in the appropriate MemoryBuffer. 758const char *SourceManager::getCharacterData(SourceLocation SL, 759 bool *Invalid) const { 760 // Note that this is a hot function in the getSpelling() path, which is 761 // heavily used by -E mode. 762 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(SL); 763 764 // Note that calling 'getBuffer()' may lazily page in a source file. 765 bool CharDataInvalid = false; 766 const llvm::MemoryBuffer *Buffer 767 = getSLocEntry(LocInfo.first).getFile().getContentCache() 768 ->getBuffer(Diag, *this, SourceLocation(), &CharDataInvalid); 769 if (Invalid) 770 *Invalid = CharDataInvalid; 771 return Buffer->getBufferStart() + (CharDataInvalid? 0 : LocInfo.second); 772} 773 774 775/// getColumnNumber - Return the column # for the specified file position. 776/// this is significantly cheaper to compute than the line number. 777unsigned SourceManager::getColumnNumber(FileID FID, unsigned FilePos, 778 bool *Invalid) const { 779 bool MyInvalid = false; 780 const char *Buf = getBuffer(FID, &MyInvalid)->getBufferStart(); 781 if (Invalid) 782 *Invalid = MyInvalid; 783 784 if (MyInvalid) 785 return 1; 786 787 unsigned LineStart = FilePos; 788 while (LineStart && Buf[LineStart-1] != '\n' && Buf[LineStart-1] != '\r') 789 --LineStart; 790 return FilePos-LineStart+1; 791} 792 793unsigned SourceManager::getSpellingColumnNumber(SourceLocation Loc, 794 bool *Invalid) const { 795 if (Loc.isInvalid()) return 0; 796 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(Loc); 797 return getColumnNumber(LocInfo.first, LocInfo.second, Invalid); 798} 799 800unsigned SourceManager::getInstantiationColumnNumber(SourceLocation Loc, 801 bool *Invalid) const { 802 if (Loc.isInvalid()) return 0; 803 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 804 return getColumnNumber(LocInfo.first, LocInfo.second, Invalid); 805} 806 807static DISABLE_INLINE void 808ComputeLineNumbers(Diagnostic &Diag, ContentCache *FI, 809 llvm::BumpPtrAllocator &Alloc, 810 const SourceManager &SM, bool &Invalid); 811static void ComputeLineNumbers(Diagnostic &Diag, ContentCache *FI, 812 llvm::BumpPtrAllocator &Alloc, 813 const SourceManager &SM, bool &Invalid) { 814 // Note that calling 'getBuffer()' may lazily page in the file. 815 const MemoryBuffer *Buffer = FI->getBuffer(Diag, SM, SourceLocation(), 816 &Invalid); 817 if (Invalid) 818 return; 819 820 // Find the file offsets of all of the *physical* source lines. This does 821 // not look at trigraphs, escaped newlines, or anything else tricky. 822 std::vector<unsigned> LineOffsets; 823 824 // Line #1 starts at char 0. 825 LineOffsets.push_back(0); 826 827 const unsigned char *Buf = (const unsigned char *)Buffer->getBufferStart(); 828 const unsigned char *End = (const unsigned char *)Buffer->getBufferEnd(); 829 unsigned Offs = 0; 830 while (1) { 831 // Skip over the contents of the line. 832 // TODO: Vectorize this? This is very performance sensitive for programs 833 // with lots of diagnostics and in -E mode. 834 const unsigned char *NextBuf = (const unsigned char *)Buf; 835 while (*NextBuf != '\n' && *NextBuf != '\r' && *NextBuf != '\0') 836 ++NextBuf; 837 Offs += NextBuf-Buf; 838 Buf = NextBuf; 839 840 if (Buf[0] == '\n' || Buf[0] == '\r') { 841 // If this is \n\r or \r\n, skip both characters. 842 if ((Buf[1] == '\n' || Buf[1] == '\r') && Buf[0] != Buf[1]) 843 ++Offs, ++Buf; 844 ++Offs, ++Buf; 845 LineOffsets.push_back(Offs); 846 } else { 847 // Otherwise, this is a null. If end of file, exit. 848 if (Buf == End) break; 849 // Otherwise, skip the null. 850 ++Offs, ++Buf; 851 } 852 } 853 854 // Copy the offsets into the FileInfo structure. 855 FI->NumLines = LineOffsets.size(); 856 FI->SourceLineCache = Alloc.Allocate<unsigned>(LineOffsets.size()); 857 std::copy(LineOffsets.begin(), LineOffsets.end(), FI->SourceLineCache); 858} 859 860/// getLineNumber - Given a SourceLocation, return the spelling line number 861/// for the position indicated. This requires building and caching a table of 862/// line offsets for the MemoryBuffer, so this is not cheap: use only when 863/// about to emit a diagnostic. 864unsigned SourceManager::getLineNumber(FileID FID, unsigned FilePos, 865 bool *Invalid) const { 866 ContentCache *Content; 867 if (LastLineNoFileIDQuery == FID) 868 Content = LastLineNoContentCache; 869 else 870 Content = const_cast<ContentCache*>(getSLocEntry(FID) 871 .getFile().getContentCache()); 872 873 // If this is the first use of line information for this buffer, compute the 874 /// SourceLineCache for it on demand. 875 if (Content->SourceLineCache == 0) { 876 bool MyInvalid = false; 877 ComputeLineNumbers(Diag, Content, ContentCacheAlloc, *this, MyInvalid); 878 if (Invalid) 879 *Invalid = MyInvalid; 880 if (MyInvalid) 881 return 1; 882 } else if (Invalid) 883 *Invalid = false; 884 885 // Okay, we know we have a line number table. Do a binary search to find the 886 // line number that this character position lands on. 887 unsigned *SourceLineCache = Content->SourceLineCache; 888 unsigned *SourceLineCacheStart = SourceLineCache; 889 unsigned *SourceLineCacheEnd = SourceLineCache + Content->NumLines; 890 891 unsigned QueriedFilePos = FilePos+1; 892 893 // FIXME: I would like to be convinced that this code is worth being as 894 // complicated as it is, binary search isn't that slow. 895 // 896 // If it is worth being optimized, then in my opinion it could be more 897 // performant, simpler, and more obviously correct by just "galloping" outward 898 // from the queried file position. In fact, this could be incorporated into a 899 // generic algorithm such as lower_bound_with_hint. 900 // 901 // If someone gives me a test case where this matters, and I will do it! - DWD 902 903 // If the previous query was to the same file, we know both the file pos from 904 // that query and the line number returned. This allows us to narrow the 905 // search space from the entire file to something near the match. 906 if (LastLineNoFileIDQuery == FID) { 907 if (QueriedFilePos >= LastLineNoFilePos) { 908 // FIXME: Potential overflow? 909 SourceLineCache = SourceLineCache+LastLineNoResult-1; 910 911 // The query is likely to be nearby the previous one. Here we check to 912 // see if it is within 5, 10 or 20 lines. It can be far away in cases 913 // where big comment blocks and vertical whitespace eat up lines but 914 // contribute no tokens. 915 if (SourceLineCache+5 < SourceLineCacheEnd) { 916 if (SourceLineCache[5] > QueriedFilePos) 917 SourceLineCacheEnd = SourceLineCache+5; 918 else if (SourceLineCache+10 < SourceLineCacheEnd) { 919 if (SourceLineCache[10] > QueriedFilePos) 920 SourceLineCacheEnd = SourceLineCache+10; 921 else if (SourceLineCache+20 < SourceLineCacheEnd) { 922 if (SourceLineCache[20] > QueriedFilePos) 923 SourceLineCacheEnd = SourceLineCache+20; 924 } 925 } 926 } 927 } else { 928 if (LastLineNoResult < Content->NumLines) 929 SourceLineCacheEnd = SourceLineCache+LastLineNoResult+1; 930 } 931 } 932 933 // If the spread is large, do a "radix" test as our initial guess, based on 934 // the assumption that lines average to approximately the same length. 935 // NOTE: This is currently disabled, as it does not appear to be profitable in 936 // initial measurements. 937 if (0 && SourceLineCacheEnd-SourceLineCache > 20) { 938 unsigned FileLen = Content->SourceLineCache[Content->NumLines-1]; 939 940 // Take a stab at guessing where it is. 941 unsigned ApproxPos = Content->NumLines*QueriedFilePos / FileLen; 942 943 // Check for -10 and +10 lines. 944 unsigned LowerBound = std::max(int(ApproxPos-10), 0); 945 unsigned UpperBound = std::min(ApproxPos+10, FileLen); 946 947 // If the computed lower bound is less than the query location, move it in. 948 if (SourceLineCache < SourceLineCacheStart+LowerBound && 949 SourceLineCacheStart[LowerBound] < QueriedFilePos) 950 SourceLineCache = SourceLineCacheStart+LowerBound; 951 952 // If the computed upper bound is greater than the query location, move it. 953 if (SourceLineCacheEnd > SourceLineCacheStart+UpperBound && 954 SourceLineCacheStart[UpperBound] >= QueriedFilePos) 955 SourceLineCacheEnd = SourceLineCacheStart+UpperBound; 956 } 957 958 unsigned *Pos 959 = std::lower_bound(SourceLineCache, SourceLineCacheEnd, QueriedFilePos); 960 unsigned LineNo = Pos-SourceLineCacheStart; 961 962 LastLineNoFileIDQuery = FID; 963 LastLineNoContentCache = Content; 964 LastLineNoFilePos = QueriedFilePos; 965 LastLineNoResult = LineNo; 966 return LineNo; 967} 968 969unsigned SourceManager::getInstantiationLineNumber(SourceLocation Loc, 970 bool *Invalid) const { 971 if (Loc.isInvalid()) return 0; 972 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 973 return getLineNumber(LocInfo.first, LocInfo.second); 974} 975unsigned SourceManager::getSpellingLineNumber(SourceLocation Loc, 976 bool *Invalid) const { 977 if (Loc.isInvalid()) return 0; 978 std::pair<FileID, unsigned> LocInfo = getDecomposedSpellingLoc(Loc); 979 return getLineNumber(LocInfo.first, LocInfo.second); 980} 981 982/// getFileCharacteristic - return the file characteristic of the specified 983/// source location, indicating whether this is a normal file, a system 984/// header, or an "implicit extern C" system header. 985/// 986/// This state can be modified with flags on GNU linemarker directives like: 987/// # 4 "foo.h" 3 988/// which changes all source locations in the current file after that to be 989/// considered to be from a system header. 990SrcMgr::CharacteristicKind 991SourceManager::getFileCharacteristic(SourceLocation Loc) const { 992 assert(!Loc.isInvalid() && "Can't get file characteristic of invalid loc!"); 993 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 994 const SrcMgr::FileInfo &FI = getSLocEntry(LocInfo.first).getFile(); 995 996 // If there are no #line directives in this file, just return the whole-file 997 // state. 998 if (!FI.hasLineDirectives()) 999 return FI.getFileCharacteristic(); 1000 1001 assert(LineTable && "Can't have linetable entries without a LineTable!"); 1002 // See if there is a #line directive before the location. 1003 const LineEntry *Entry = 1004 LineTable->FindNearestLineEntry(LocInfo.first.ID, LocInfo.second); 1005 1006 // If this is before the first line marker, use the file characteristic. 1007 if (!Entry) 1008 return FI.getFileCharacteristic(); 1009 1010 return Entry->FileKind; 1011} 1012 1013/// Return the filename or buffer identifier of the buffer the location is in. 1014/// Note that this name does not respect #line directives. Use getPresumedLoc 1015/// for normal clients. 1016const char *SourceManager::getBufferName(SourceLocation Loc, 1017 bool *Invalid) const { 1018 if (Loc.isInvalid()) return "<invalid loc>"; 1019 1020 return getBuffer(getFileID(Loc), Invalid)->getBufferIdentifier(); 1021} 1022 1023 1024/// getPresumedLoc - This method returns the "presumed" location of a 1025/// SourceLocation specifies. A "presumed location" can be modified by #line 1026/// or GNU line marker directives. This provides a view on the data that a 1027/// user should see in diagnostics, for example. 1028/// 1029/// Note that a presumed location is always given as the instantiation point 1030/// of an instantiation location, not at the spelling location. 1031PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc) const { 1032 if (Loc.isInvalid()) return PresumedLoc(); 1033 1034 // Presumed locations are always for instantiation points. 1035 std::pair<FileID, unsigned> LocInfo = getDecomposedInstantiationLoc(Loc); 1036 1037 const SrcMgr::FileInfo &FI = getSLocEntry(LocInfo.first).getFile(); 1038 const SrcMgr::ContentCache *C = FI.getContentCache(); 1039 1040 // To get the source name, first consult the FileEntry (if one exists) 1041 // before the MemBuffer as this will avoid unnecessarily paging in the 1042 // MemBuffer. 1043 const char *Filename; 1044 if (C->Entry) 1045 Filename = C->Entry->getName(); 1046 else 1047 Filename = C->getBuffer(Diag, *this)->getBufferIdentifier(); 1048 unsigned LineNo = getLineNumber(LocInfo.first, LocInfo.second); 1049 unsigned ColNo = getColumnNumber(LocInfo.first, LocInfo.second); 1050 SourceLocation IncludeLoc = FI.getIncludeLoc(); 1051 1052 // If we have #line directives in this file, update and overwrite the physical 1053 // location info if appropriate. 1054 if (FI.hasLineDirectives()) { 1055 assert(LineTable && "Can't have linetable entries without a LineTable!"); 1056 // See if there is a #line directive before this. If so, get it. 1057 if (const LineEntry *Entry = 1058 LineTable->FindNearestLineEntry(LocInfo.first.ID, LocInfo.second)) { 1059 // If the LineEntry indicates a filename, use it. 1060 if (Entry->FilenameID != -1) 1061 Filename = LineTable->getFilename(Entry->FilenameID); 1062 1063 // Use the line number specified by the LineEntry. This line number may 1064 // be multiple lines down from the line entry. Add the difference in 1065 // physical line numbers from the query point and the line marker to the 1066 // total. 1067 unsigned MarkerLineNo = getLineNumber(LocInfo.first, Entry->FileOffset); 1068 LineNo = Entry->LineNo + (LineNo-MarkerLineNo-1); 1069 1070 // Note that column numbers are not molested by line markers. 1071 1072 // Handle virtual #include manipulation. 1073 if (Entry->IncludeOffset) { 1074 IncludeLoc = getLocForStartOfFile(LocInfo.first); 1075 IncludeLoc = IncludeLoc.getFileLocWithOffset(Entry->IncludeOffset); 1076 } 1077 } 1078 } 1079 1080 return PresumedLoc(Filename, LineNo, ColNo, IncludeLoc); 1081} 1082 1083//===----------------------------------------------------------------------===// 1084// Other miscellaneous methods. 1085//===----------------------------------------------------------------------===// 1086 1087/// \brief Get the source location for the given file:line:col triplet. 1088/// 1089/// If the source file is included multiple times, the source location will 1090/// be based upon the first inclusion. 1091SourceLocation SourceManager::getLocation(const FileEntry *SourceFile, 1092 unsigned Line, unsigned Col) const { 1093 assert(SourceFile && "Null source file!"); 1094 assert(Line && Col && "Line and column should start from 1!"); 1095 1096 fileinfo_iterator FI = FileInfos.find(SourceFile); 1097 if (FI == FileInfos.end()) 1098 return SourceLocation(); 1099 ContentCache *Content = FI->second; 1100 1101 // If this is the first use of line information for this buffer, compute the 1102 /// SourceLineCache for it on demand. 1103 if (Content->SourceLineCache == 0) { 1104 bool MyInvalid = false; 1105 ComputeLineNumbers(Diag, Content, ContentCacheAlloc, *this, MyInvalid); 1106 if (MyInvalid) 1107 return SourceLocation(); 1108 } 1109 1110 // Find the first file ID that corresponds to the given file. 1111 FileID FirstFID; 1112 1113 // First, check the main file ID, since it is common to look for a 1114 // location in the main file. 1115 if (!MainFileID.isInvalid()) { 1116 const SLocEntry &MainSLoc = getSLocEntry(MainFileID); 1117 if (MainSLoc.isFile() && MainSLoc.getFile().getContentCache() == Content) 1118 FirstFID = MainFileID; 1119 } 1120 1121 if (FirstFID.isInvalid()) { 1122 // The location we're looking for isn't in the main file; look 1123 // through all of the source locations. 1124 for (unsigned I = 0, N = sloc_entry_size(); I != N; ++I) { 1125 const SLocEntry &SLoc = getSLocEntry(I); 1126 if (SLoc.isFile() && SLoc.getFile().getContentCache() == Content) { 1127 FirstFID = FileID::get(I); 1128 break; 1129 } 1130 } 1131 } 1132 1133 if (FirstFID.isInvalid()) 1134 return SourceLocation(); 1135 1136 if (Line > Content->NumLines) { 1137 unsigned Size = Content->getBuffer(Diag, *this)->getBufferSize(); 1138 if (Size > 0) 1139 --Size; 1140 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(Size); 1141 } 1142 1143 unsigned FilePos = Content->SourceLineCache[Line - 1]; 1144 const char *Buf = Content->getBuffer(Diag, *this)->getBufferStart() + FilePos; 1145 unsigned BufLength = Content->getBuffer(Diag, *this)->getBufferEnd() - Buf; 1146 unsigned i = 0; 1147 1148 // Check that the given column is valid. 1149 while (i < BufLength-1 && i < Col-1 && Buf[i] != '\n' && Buf[i] != '\r') 1150 ++i; 1151 if (i < Col-1) 1152 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(FilePos + i); 1153 1154 return getLocForStartOfFile(FirstFID).getFileLocWithOffset(FilePos + Col - 1); 1155} 1156 1157/// \brief Determines the order of 2 source locations in the translation unit. 1158/// 1159/// \returns true if LHS source location comes before RHS, false otherwise. 1160bool SourceManager::isBeforeInTranslationUnit(SourceLocation LHS, 1161 SourceLocation RHS) const { 1162 assert(LHS.isValid() && RHS.isValid() && "Passed invalid source location!"); 1163 if (LHS == RHS) 1164 return false; 1165 1166 std::pair<FileID, unsigned> LOffs = getDecomposedLoc(LHS); 1167 std::pair<FileID, unsigned> ROffs = getDecomposedLoc(RHS); 1168 1169 // If the source locations are in the same file, just compare offsets. 1170 if (LOffs.first == ROffs.first) 1171 return LOffs.second < ROffs.second; 1172 1173 // If we are comparing a source location with multiple locations in the same 1174 // file, we get a big win by caching the result. 1175 if (IsBeforeInTUCache.isCacheValid(LOffs.first, ROffs.first)) 1176 return IsBeforeInTUCache.getCachedResult(LOffs.second, ROffs.second); 1177 1178 // Okay, we missed in the cache, start updating the cache for this query. 1179 IsBeforeInTUCache.setQueryFIDs(LOffs.first, ROffs.first); 1180 1181 // "Traverse" the include/instantiation stacks of both locations and try to 1182 // find a common "ancestor". FileIDs build a tree-like structure that 1183 // reflects the #include hierarchy, and this algorithm needs to find the 1184 // nearest common ancestor between the two locations. For example, if you 1185 // have a.c that includes b.h and c.h, and are comparing a location in b.h to 1186 // a location in c.h, we need to find that their nearest common ancestor is 1187 // a.c, and compare the locations of the two #includes to find their relative 1188 // ordering. 1189 // 1190 // SourceManager assigns FileIDs in order of parsing. This means that an 1191 // includee always has a larger FileID than an includer. While you might 1192 // think that we could just compare the FileID's here, that doesn't work to 1193 // compare a point at the end of a.c with a point within c.h. Though c.h has 1194 // a larger FileID, we have to compare the include point of c.h to the 1195 // location in a.c. 1196 // 1197 // Despite not being able to directly compare FileID's, we can tell that a 1198 // larger FileID is necessarily more deeply nested than a lower one and use 1199 // this information to walk up the tree to the nearest common ancestor. 1200 do { 1201 // If LOffs is larger than ROffs, then LOffs must be more deeply nested than 1202 // ROffs, walk up the #include chain. 1203 if (LOffs.first.ID > ROffs.first.ID) { 1204 SourceLocation UpperLoc; 1205 const SrcMgr::SLocEntry &Entry = getSLocEntry(LOffs.first); 1206 if (Entry.isInstantiation()) 1207 UpperLoc = Entry.getInstantiation().getInstantiationLocStart(); 1208 else 1209 UpperLoc = Entry.getFile().getIncludeLoc(); 1210 1211 if (UpperLoc.isInvalid()) 1212 break; // We reached the top. 1213 1214 LOffs = getDecomposedLoc(UpperLoc); 1215 } else { 1216 // Otherwise, ROffs is larger than LOffs, so ROffs must be more deeply 1217 // nested than LOffs, walk up the #include chain. 1218 SourceLocation UpperLoc; 1219 const SrcMgr::SLocEntry &Entry = getSLocEntry(ROffs.first); 1220 if (Entry.isInstantiation()) 1221 UpperLoc = Entry.getInstantiation().getInstantiationLocStart(); 1222 else 1223 UpperLoc = Entry.getFile().getIncludeLoc(); 1224 1225 if (UpperLoc.isInvalid()) 1226 break; // We reached the top. 1227 1228 ROffs = getDecomposedLoc(UpperLoc); 1229 } 1230 } while (LOffs.first != ROffs.first); 1231 1232 // If we exited because we found a nearest common ancestor, compare the 1233 // locations within the common file and cache them. 1234 if (LOffs.first == ROffs.first) { 1235 IsBeforeInTUCache.setCommonLoc(LOffs.first, LOffs.second, ROffs.second); 1236 return IsBeforeInTUCache.getCachedResult(LOffs.second, ROffs.second); 1237 } 1238 1239 // There is no common ancestor, most probably because one location is in the 1240 // predefines buffer. 1241 IsBeforeInTUCache.setQueryFIDs(FileID(), FileID()); // Don't try caching. 1242 1243 // FIXME: We should rearrange the external interface so this simply never 1244 // happens; it can't conceptually happen. Also see PR5662. 1245 1246 // If exactly one location is a memory buffer, assume it preceeds the other. 1247 bool LIsMB = !getSLocEntry(LOffs.first).getFile().getContentCache()->Entry; 1248 bool RIsMB = !getSLocEntry(ROffs.first).getFile().getContentCache()->Entry; 1249 if (LIsMB != RIsMB) 1250 return LIsMB; 1251 1252 // Otherwise, just assume FileIDs were created in order. 1253 return LOffs.first < ROffs.first; 1254} 1255 1256/// PrintStats - Print statistics to stderr. 1257/// 1258void SourceManager::PrintStats() const { 1259 llvm::errs() << "\n*** Source Manager Stats:\n"; 1260 llvm::errs() << FileInfos.size() << " files mapped, " << MemBufferInfos.size() 1261 << " mem buffers mapped.\n"; 1262 llvm::errs() << SLocEntryTable.size() << " SLocEntry's allocated, " 1263 << NextOffset << "B of Sloc address space used.\n"; 1264 1265 unsigned NumLineNumsComputed = 0; 1266 unsigned NumFileBytesMapped = 0; 1267 for (fileinfo_iterator I = fileinfo_begin(), E = fileinfo_end(); I != E; ++I){ 1268 NumLineNumsComputed += I->second->SourceLineCache != 0; 1269 NumFileBytesMapped += I->second->getSizeBytesMapped(); 1270 } 1271 1272 llvm::errs() << NumFileBytesMapped << " bytes of files mapped, " 1273 << NumLineNumsComputed << " files with line #'s computed.\n"; 1274 llvm::errs() << "FileID scans: " << NumLinearScans << " linear, " 1275 << NumBinaryProbes << " binary.\n"; 1276} 1277 1278ExternalSLocEntrySource::~ExternalSLocEntrySource() { } 1279