- //===- SourceManager.h - Track and cache source files -----------*- C++ -*-===// 
- // 
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
- // See https://llvm.org/LICENSE.txt for license information. 
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
- // 
- //===----------------------------------------------------------------------===// 
- // 
- /// \file 
- /// Defines the SourceManager interface. 
- /// 
- /// There are three different types of locations in a %file: a spelling 
- /// location, an expansion location, and a presumed location. 
- /// 
- /// Given an example of: 
- /// \code 
- /// #define min(x, y) x < y ? x : y 
- /// \endcode 
- /// 
- /// and then later on a use of min: 
- /// \code 
- /// #line 17 
- /// return min(a, b); 
- /// \endcode 
- /// 
- /// The expansion location is the line in the source code where the macro 
- /// was expanded (the return statement), the spelling location is the 
- /// location in the source where the macro was originally defined, 
- /// and the presumed location is where the line directive states that 
- /// the line is 17, or any other line. 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_CLANG_BASIC_SOURCEMANAGER_H 
- #define LLVM_CLANG_BASIC_SOURCEMANAGER_H 
-   
- #include "clang/Basic/Diagnostic.h" 
- #include "clang/Basic/FileEntry.h" 
- #include "clang/Basic/FileManager.h" 
- #include "clang/Basic/SourceLocation.h" 
- #include "llvm/ADT/ArrayRef.h" 
- #include "llvm/ADT/BitVector.h" 
- #include "llvm/ADT/DenseMap.h" 
- #include "llvm/ADT/DenseSet.h" 
- #include "llvm/ADT/IntrusiveRefCntPtr.h" 
- #include "llvm/ADT/PointerIntPair.h" 
- #include "llvm/ADT/SmallVector.h" 
- #include "llvm/ADT/StringRef.h" 
- #include "llvm/Support/Allocator.h" 
- #include "llvm/Support/Compiler.h" 
- #include "llvm/Support/MemoryBuffer.h" 
- #include <cassert> 
- #include <cstddef> 
- #include <map> 
- #include <memory> 
- #include <optional> 
- #include <string> 
- #include <utility> 
- #include <vector> 
-   
- namespace clang { 
-   
- class ASTReader; 
- class ASTWriter; 
- class FileManager; 
- class LineTableInfo; 
- class SourceManager; 
-   
- /// Public enums and private classes that are part of the 
- /// SourceManager implementation. 
- namespace SrcMgr { 
-   
- /// Indicates whether a file or directory holds normal user code, 
- /// system code, or system code which is implicitly 'extern "C"' in C++ mode. 
- /// 
- /// Entire directories can be tagged with this (this is maintained by 
- /// DirectoryLookup and friends) as can specific FileInfos when a \#pragma 
- /// system_header is seen or in various other cases. 
- /// 
- enum CharacteristicKind { 
-   C_User, 
-   C_System, 
-   C_ExternCSystem, 
-   C_User_ModuleMap, 
-   C_System_ModuleMap 
- }; 
-   
- /// Determine whether a file / directory characteristic is for system code. 
- inline bool isSystem(CharacteristicKind CK) { 
-   return CK != C_User && CK != C_User_ModuleMap; 
- } 
-   
- /// Determine whether a file characteristic is for a module map. 
- inline bool isModuleMap(CharacteristicKind CK) { 
-   return CK == C_User_ModuleMap || CK == C_System_ModuleMap; 
- } 
-   
- /// Mapping of line offsets into a source file. This does not own the storage 
- /// for the line numbers. 
- class LineOffsetMapping { 
- public: 
-   explicit operator bool() const { return Storage; } 
-   unsigned size() const { 
-     assert(Storage); 
-     return Storage[0]; 
-   } 
-   ArrayRef<unsigned> getLines() const { 
-     assert(Storage); 
-     return ArrayRef<unsigned>(Storage + 1, Storage + 1 + size()); 
-   } 
-   const unsigned *begin() const { return getLines().begin(); } 
-   const unsigned *end() const { return getLines().end(); } 
-   const unsigned &operator[](int I) const { return getLines()[I]; } 
-   
-   static LineOffsetMapping get(llvm::MemoryBufferRef Buffer, 
-                                llvm::BumpPtrAllocator &Alloc); 
-   
-   LineOffsetMapping() = default; 
-   LineOffsetMapping(ArrayRef<unsigned> LineOffsets, 
-                     llvm::BumpPtrAllocator &Alloc); 
-   
- private: 
-   /// First element is the size, followed by elements at off-by-one indexes. 
-   unsigned *Storage = nullptr; 
- }; 
-   
- /// One instance of this struct is kept for every file loaded or used. 
- /// 
- /// This object owns the MemoryBuffer object. 
- class alignas(8) ContentCache { 
-   /// The actual buffer containing the characters from the input 
-   /// file. 
-   mutable std::unique_ptr<llvm::MemoryBuffer> Buffer; 
-   
- public: 
-   /// Reference to the file entry representing this ContentCache. 
-   /// 
-   /// This reference does not own the FileEntry object. 
-   /// 
-   /// It is possible for this to be NULL if the ContentCache encapsulates 
-   /// an imaginary text buffer. 
-   /// 
-   /// FIXME: Make non-optional using a virtual file as needed, remove \c 
-   /// Filename and use \c OrigEntry.getNameAsRequested() instead. 
-   OptionalFileEntryRefDegradesToFileEntryPtr OrigEntry; 
-   
-   /// References the file which the contents were actually loaded from. 
-   /// 
-   /// Can be different from 'Entry' if we overridden the contents of one file 
-   /// with the contents of another file. 
-   const FileEntry *ContentsEntry; 
-   
-   /// The filename that is used to access OrigEntry. 
-   /// 
-   /// FIXME: Remove this once OrigEntry is a FileEntryRef with a stable name. 
-   StringRef Filename; 
-   
-   /// A bump pointer allocated array of offsets for each source line. 
-   /// 
-   /// This is lazily computed.  The lines are owned by the SourceManager 
-   /// BumpPointerAllocator object. 
-   mutable LineOffsetMapping SourceLineCache; 
-   
-   /// Indicates whether the buffer itself was provided to override 
-   /// the actual file contents. 
-   /// 
-   /// When true, the original entry may be a virtual file that does not 
-   /// exist. 
-   unsigned BufferOverridden : 1; 
-   
-   /// True if this content cache was initially created for a source file 
-   /// considered to be volatile (likely to change between stat and open). 
-   unsigned IsFileVolatile : 1; 
-   
-   /// True if this file may be transient, that is, if it might not 
-   /// exist at some later point in time when this content entry is used, 
-   /// after serialization and deserialization. 
-   unsigned IsTransient : 1; 
-   
-   mutable unsigned IsBufferInvalid : 1; 
-   
-   ContentCache() 
-       : OrigEntry(std::nullopt), ContentsEntry(nullptr), 
-         BufferOverridden(false), IsFileVolatile(false), IsTransient(false), 
-         IsBufferInvalid(false) {} 
-   
-   ContentCache(FileEntryRef Ent) : ContentCache(Ent, Ent) {} 
-   
-   ContentCache(FileEntryRef Ent, const FileEntry *contentEnt) 
-       : OrigEntry(Ent), ContentsEntry(contentEnt), BufferOverridden(false), 
-         IsFileVolatile(false), IsTransient(false), IsBufferInvalid(false) {} 
-   
-   /// The copy ctor does not allow copies where source object has either 
-   /// a non-NULL Buffer or SourceLineCache.  Ownership of allocated memory 
-   /// is not transferred, so this is a logical error. 
-   ContentCache(const ContentCache &RHS) 
-       : BufferOverridden(false), IsFileVolatile(false), IsTransient(false), 
-         IsBufferInvalid(false) { 
-     OrigEntry = RHS.OrigEntry; 
-     ContentsEntry = RHS.ContentsEntry; 
-   
-     assert(!RHS.Buffer && !RHS.SourceLineCache && 
-            "Passed ContentCache object cannot own a buffer."); 
-   } 
-   
-   ContentCache &operator=(const ContentCache &RHS) = delete; 
-   
-   /// Returns the memory buffer for the associated content. 
-   /// 
-   /// \param Diag Object through which diagnostics will be emitted if the 
-   ///   buffer cannot be retrieved. 
-   /// 
-   /// \param Loc If specified, is the location that invalid file diagnostics 
-   ///   will be emitted at. 
-   std::optional<llvm::MemoryBufferRef> 
-   getBufferOrNone(DiagnosticsEngine &Diag, FileManager &FM, 
-                   SourceLocation Loc = SourceLocation()) const; 
-   
-   /// Returns the size of the content encapsulated by this 
-   /// ContentCache. 
-   /// 
-   /// This can be the size of the source file or the size of an 
-   /// arbitrary scratch buffer.  If the ContentCache encapsulates a source 
-   /// file this size is retrieved from the file's FileEntry. 
-   unsigned getSize() const; 
-   
-   /// Returns the number of bytes actually mapped for this 
-   /// ContentCache. 
-   /// 
-   /// This can be 0 if the MemBuffer was not actually expanded. 
-   unsigned getSizeBytesMapped() const; 
-   
-   /// Returns the kind of memory used to back the memory buffer for 
-   /// this content cache.  This is used for performance analysis. 
-   llvm::MemoryBuffer::BufferKind getMemoryBufferKind() const; 
-   
-   /// Return the buffer, only if it has been loaded. 
-   std::optional<llvm::MemoryBufferRef> getBufferIfLoaded() const { 
-     if (Buffer) 
-       return Buffer->getMemBufferRef(); 
-     return std::nullopt; 
-   } 
-   
-   /// Return a StringRef to the source buffer data, only if it has already 
-   /// been loaded. 
-   std::optional<StringRef> getBufferDataIfLoaded() const { 
-     if (Buffer) 
-       return Buffer->getBuffer(); 
-     return std::nullopt; 
-   } 
-   
-   /// Set the buffer. 
-   void setBuffer(std::unique_ptr<llvm::MemoryBuffer> B) { 
-     IsBufferInvalid = false; 
-     Buffer = std::move(B); 
-   } 
-   
-   /// Set the buffer to one that's not owned (or to nullptr). 
-   /// 
-   /// \pre Buffer cannot already be set. 
-   void setUnownedBuffer(std::optional<llvm::MemoryBufferRef> B) { 
-     assert(!Buffer && "Expected to be called right after construction"); 
-     if (B) 
-       setBuffer(llvm::MemoryBuffer::getMemBuffer(*B)); 
-   } 
-   
-   // If BufStr has an invalid BOM, returns the BOM name; otherwise, returns 
-   // nullptr 
-   static const char *getInvalidBOM(StringRef BufStr); 
- }; 
-   
- // Assert that the \c ContentCache objects will always be 8-byte aligned so 
- // that we can pack 3 bits of integer into pointers to such objects. 
- static_assert(alignof(ContentCache) >= 8, 
-               "ContentCache must be 8-byte aligned."); 
-   
- /// Information about a FileID, basically just the logical file 
- /// that it represents and include stack information. 
- /// 
- /// Each FileInfo has include stack information, indicating where it came 
- /// from. This information encodes the \#include chain that a token was 
- /// expanded from. The main include file has an invalid IncludeLoc. 
- /// 
- /// FileInfo should not grow larger than ExpansionInfo. Doing so will 
- /// cause memory to bloat in compilations with many unloaded macro 
- /// expansions, since the two data structurs are stored in a union in 
- /// SLocEntry. Extra fields should instead go in "ContentCache *", which 
- /// stores file contents and other bits on the side. 
- /// 
- class FileInfo { 
-   friend class clang::SourceManager; 
-   friend class clang::ASTWriter; 
-   friend class clang::ASTReader; 
-   
-   /// The location of the \#include that brought in this file. 
-   /// 
-   /// This is an invalid SLOC for the main file (top of the \#include chain). 
-   SourceLocation IncludeLoc; 
-   
-   /// Number of FileIDs (files and macros) that were created during 
-   /// preprocessing of this \#include, including this SLocEntry. 
-   /// 
-   /// Zero means the preprocessor didn't provide such info for this SLocEntry. 
-   unsigned NumCreatedFIDs : 31; 
-   
-   /// Whether this FileInfo has any \#line directives. 
-   unsigned HasLineDirectives : 1; 
-   
-   /// The content cache and the characteristic of the file. 
-   llvm::PointerIntPair<const ContentCache *, 3, CharacteristicKind> 
-       ContentAndKind; 
-   
- public: 
-   /// Return a FileInfo object. 
-   static FileInfo get(SourceLocation IL, ContentCache &Con, 
-                       CharacteristicKind FileCharacter, StringRef Filename) { 
-     FileInfo X; 
-     X.IncludeLoc = IL; 
-     X.NumCreatedFIDs = 0; 
-     X.HasLineDirectives = false; 
-     X.ContentAndKind.setPointer(&Con); 
-     X.ContentAndKind.setInt(FileCharacter); 
-     Con.Filename = Filename; 
-     return X; 
-   } 
-   
-   SourceLocation getIncludeLoc() const { 
-     return IncludeLoc; 
-   } 
-   
-   const ContentCache &getContentCache() const { 
-     return *ContentAndKind.getPointer(); 
-   } 
-   
-   /// Return whether this is a system header or not. 
-   CharacteristicKind getFileCharacteristic() const { 
-     return ContentAndKind.getInt(); 
-   } 
-   
-   /// Return true if this FileID has \#line directives in it. 
-   bool hasLineDirectives() const { return HasLineDirectives; } 
-   
-   /// Set the flag that indicates that this FileID has 
-   /// line table entries associated with it. 
-   void setHasLineDirectives() { HasLineDirectives = true; } 
-   
-   /// Returns the name of the file that was used when the file was loaded from 
-   /// the underlying file system. 
-   StringRef getName() const { return getContentCache().Filename; } 
- }; 
-   
- /// Each ExpansionInfo encodes the expansion location - where 
- /// the token was ultimately expanded, and the SpellingLoc - where the actual 
- /// character data for the token came from. 
- class ExpansionInfo { 
-   // Really these are all SourceLocations. 
-   
-   /// Where the spelling for the token can be found. 
-   SourceLocation SpellingLoc; 
-   
-   /// In a macro expansion, ExpansionLocStart and ExpansionLocEnd 
-   /// indicate the start and end of the expansion. In object-like macros, 
-   /// they will be the same. In a function-like macro expansion, the start 
-   /// will be the identifier and the end will be the ')'. Finally, in 
-   /// macro-argument instantiations, the end will be 'SourceLocation()', an 
-   /// invalid location. 
-   SourceLocation ExpansionLocStart, ExpansionLocEnd; 
-   
-   /// Whether the expansion range is a token range. 
-   bool ExpansionIsTokenRange; 
-   
- public: 
-   SourceLocation getSpellingLoc() const { 
-     return SpellingLoc.isInvalid() ? getExpansionLocStart() : SpellingLoc; 
-   } 
-   
-   SourceLocation getExpansionLocStart() const { 
-     return ExpansionLocStart; 
-   } 
-   
-   SourceLocation getExpansionLocEnd() const { 
-     return ExpansionLocEnd.isInvalid() ? getExpansionLocStart() 
-                                        : ExpansionLocEnd; 
-   } 
-   
-   bool isExpansionTokenRange() const { return ExpansionIsTokenRange; } 
-   
-   CharSourceRange getExpansionLocRange() const { 
-     return CharSourceRange( 
-         SourceRange(getExpansionLocStart(), getExpansionLocEnd()), 
-         isExpansionTokenRange()); 
-   } 
-   
-   bool isMacroArgExpansion() const { 
-     // Note that this needs to return false for default constructed objects. 
-     return getExpansionLocStart().isValid() && ExpansionLocEnd.isInvalid(); 
-   } 
-   
-   bool isMacroBodyExpansion() const { 
-     return getExpansionLocStart().isValid() && ExpansionLocEnd.isValid(); 
-   } 
-   
-   bool isFunctionMacroExpansion() const { 
-     return getExpansionLocStart().isValid() && 
-            getExpansionLocStart() != getExpansionLocEnd(); 
-   } 
-   
-   /// Return a ExpansionInfo for an expansion. 
-   /// 
-   /// Start and End specify the expansion range (where the macro is 
-   /// expanded), and SpellingLoc specifies the spelling location (where 
-   /// the characters from the token come from). All three can refer to 
-   /// normal File SLocs or expansion locations. 
-   static ExpansionInfo create(SourceLocation SpellingLoc, SourceLocation Start, 
-                               SourceLocation End, 
-                               bool ExpansionIsTokenRange = true) { 
-     ExpansionInfo X; 
-     X.SpellingLoc = SpellingLoc; 
-     X.ExpansionLocStart = Start; 
-     X.ExpansionLocEnd = End; 
-     X.ExpansionIsTokenRange = ExpansionIsTokenRange; 
-     return X; 
-   } 
-   
-   /// Return a special ExpansionInfo for the expansion of 
-   /// a macro argument into a function-like macro's body. 
-   /// 
-   /// ExpansionLoc specifies the expansion location (where the macro is 
-   /// expanded). This doesn't need to be a range because a macro is always 
-   /// expanded at a macro parameter reference, and macro parameters are 
-   /// always exactly one token. SpellingLoc specifies the spelling location 
-   /// (where the characters from the token come from). ExpansionLoc and 
-   /// SpellingLoc can both refer to normal File SLocs or expansion locations. 
-   /// 
-   /// Given the code: 
-   /// \code 
-   ///   #define F(x) f(x) 
-   ///   F(42); 
-   /// \endcode 
-   /// 
-   /// When expanding '\c F(42)', the '\c x' would call this with an 
-   /// SpellingLoc pointing at '\c 42' and an ExpansionLoc pointing at its 
-   /// location in the definition of '\c F'. 
-   static ExpansionInfo createForMacroArg(SourceLocation SpellingLoc, 
-                                          SourceLocation ExpansionLoc) { 
-     // We store an intentionally invalid source location for the end of the 
-     // expansion range to mark that this is a macro argument location rather 
-     // than a normal one. 
-     return create(SpellingLoc, ExpansionLoc, SourceLocation()); 
-   } 
-   
-   /// Return a special ExpansionInfo representing a token that ends 
-   /// prematurely. This is used to model a '>>' token that has been split 
-   /// into '>' tokens and similar cases. Unlike for the other forms of 
-   /// expansion, the expansion range in this case is a character range, not 
-   /// a token range. 
-   static ExpansionInfo createForTokenSplit(SourceLocation SpellingLoc, 
-                                            SourceLocation Start, 
-                                            SourceLocation End) { 
-     return create(SpellingLoc, Start, End, false); 
-   } 
- }; 
-   
- // Assert that the \c FileInfo objects are no bigger than \c ExpansionInfo 
- // objects. This controls the size of \c SLocEntry, of which we have one for 
- // each macro expansion. The number of (unloaded) macro expansions can be 
- // very large. Any other fields needed in FileInfo should go in ContentCache. 
- static_assert(sizeof(FileInfo) <= sizeof(ExpansionInfo), 
-               "FileInfo must be no larger than ExpansionInfo."); 
-   
- /// This is a discriminated union of FileInfo and ExpansionInfo. 
- /// 
- /// SourceManager keeps an array of these objects, and they are uniquely 
- /// identified by the FileID datatype. 
- class SLocEntry { 
-   static constexpr int OffsetBits = 8 * sizeof(SourceLocation::UIntTy) - 1; 
-   SourceLocation::UIntTy Offset : OffsetBits; 
-   SourceLocation::UIntTy IsExpansion : 1; 
-   union { 
-     FileInfo File; 
-     ExpansionInfo Expansion; 
-   }; 
-   
- public: 
-   SLocEntry() : Offset(), IsExpansion(), File() {} 
-   
-   SourceLocation::UIntTy getOffset() const { return Offset; } 
-   
-   bool isExpansion() const { return IsExpansion; } 
-   bool isFile() const { return !isExpansion(); } 
-   
-   const FileInfo &getFile() const { 
-     assert(isFile() && "Not a file SLocEntry!"); 
-     return File; 
-   } 
-   
-   const ExpansionInfo &getExpansion() const { 
-     assert(isExpansion() && "Not a macro expansion SLocEntry!"); 
-     return Expansion; 
-   } 
-   
-   static SLocEntry get(SourceLocation::UIntTy Offset, const FileInfo &FI) { 
-     assert(!(Offset & (1ULL << OffsetBits)) && "Offset is too large"); 
-     SLocEntry E; 
-     E.Offset = Offset; 
-     E.IsExpansion = false; 
-     E.File = FI; 
-     return E; 
-   } 
-   
-   static SLocEntry get(SourceLocation::UIntTy Offset, 
-                        const ExpansionInfo &Expansion) { 
-     assert(!(Offset & (1ULL << OffsetBits)) && "Offset is too large"); 
-     SLocEntry E; 
-     E.Offset = Offset; 
-     E.IsExpansion = true; 
-     new (&E.Expansion) ExpansionInfo(Expansion); 
-     return E; 
-   } 
- }; 
-   
- } // namespace SrcMgr 
-   
- /// External source of source location entries. 
- class ExternalSLocEntrySource { 
- public: 
-   virtual ~ExternalSLocEntrySource(); 
-   
-   /// Read the source location entry with index ID, which will always be 
-   /// less than -1. 
-   /// 
-   /// \returns true if an error occurred that prevented the source-location 
-   /// entry from being loaded. 
-   virtual bool ReadSLocEntry(int ID) = 0; 
-   
-   /// Retrieve the module import location and name for the given ID, if 
-   /// in fact it was loaded from a module (rather than, say, a precompiled 
-   /// header). 
-   virtual std::pair<SourceLocation, StringRef> getModuleImportLoc(int ID) = 0; 
- }; 
-   
- /// Holds the cache used by isBeforeInTranslationUnit. 
- /// 
- /// The cache structure is complex enough to be worth breaking out of 
- /// SourceManager. 
- class InBeforeInTUCacheEntry { 
-   /// The FileID's of the cached query. 
-   /// 
-   /// If these match up with a subsequent query, the result can be reused. 
-   FileID LQueryFID, RQueryFID; 
-   
-   /// The relative order of FileIDs that the CommonFID *immediately* includes. 
-   /// 
-   /// This is used to compare macro expansion locations. 
-   bool LChildBeforeRChild; 
-   
-   /// The file found in common between the two \#include traces, i.e., 
-   /// the nearest common ancestor of the \#include tree. 
-   FileID CommonFID; 
-   
-   /// The offset of the previous query in CommonFID. 
-   /// 
-   /// Usually, this represents the location of the \#include for QueryFID, but 
-   /// if LQueryFID is a parent of RQueryFID (or vice versa) then these can be a 
-   /// random token in the parent. 
-   unsigned LCommonOffset, RCommonOffset; 
-   
- public: 
-   InBeforeInTUCacheEntry() = default; 
-   InBeforeInTUCacheEntry(FileID L, FileID R) : LQueryFID(L), RQueryFID(R) { 
-     assert(L != R); 
-   } 
-   
-   /// Return true if the currently cached values match up with 
-   /// the specified LHS/RHS query. 
-   /// 
-   /// If not, we can't use the cache. 
-   bool isCacheValid() const { 
-     return CommonFID.isValid(); 
-   } 
-   
-   /// If the cache is valid, compute the result given the 
-   /// specified offsets in the LHS/RHS FileID's. 
-   bool getCachedResult(unsigned LOffset, unsigned ROffset) const { 
-     // If one of the query files is the common file, use the offset.  Otherwise, 
-     // use the #include loc in the common file. 
-     if (LQueryFID != CommonFID) LOffset = LCommonOffset; 
-     if (RQueryFID != CommonFID) ROffset = RCommonOffset; 
-   
-     // It is common for multiple macro expansions to be "included" from the same 
-     // location (expansion location), in which case use the order of the FileIDs 
-     // to determine which came first. This will also take care the case where 
-     // one of the locations points at the inclusion/expansion point of the other 
-     // in which case its FileID will come before the other. 
-     if (LOffset == ROffset) 
-       return LChildBeforeRChild; 
-   
-     return LOffset < ROffset; 
-   } 
-   
-   /// Set up a new query. 
-   /// If it matches the old query, we can keep the cached answer. 
-   void setQueryFIDs(FileID LHS, FileID RHS) { 
-     assert(LHS != RHS); 
-     if (LQueryFID != LHS || RQueryFID != RHS) { 
-       LQueryFID = LHS; 
-       RQueryFID = RHS; 
-       CommonFID = FileID(); 
-     } 
-   } 
-   
-   void setCommonLoc(FileID commonFID, unsigned lCommonOffset, 
-                     unsigned rCommonOffset, bool LParentBeforeRParent) { 
-     CommonFID = commonFID; 
-     LCommonOffset = lCommonOffset; 
-     RCommonOffset = rCommonOffset; 
-     LChildBeforeRChild = LParentBeforeRParent; 
-   } 
- }; 
-   
- /// The stack used when building modules on demand, which is used 
- /// to provide a link between the source managers of the different compiler 
- /// instances. 
- using ModuleBuildStack = ArrayRef<std::pair<std::string, FullSourceLoc>>; 
-   
- /// This class handles loading and caching of source files into memory. 
- /// 
- /// This object owns the MemoryBuffer objects for all of the loaded 
- /// files and assigns unique FileID's for each unique \#include chain. 
- /// 
- /// The SourceManager can be queried for information about SourceLocation 
- /// objects, turning them into either spelling or expansion locations. Spelling 
- /// locations represent where the bytes corresponding to a token came from and 
- /// expansion locations represent where the location is in the user's view. In 
- /// the case of a macro expansion, for example, the spelling location indicates 
- /// where the expanded token came from and the expansion location specifies 
- /// where it was expanded. 
- class SourceManager : public RefCountedBase<SourceManager> { 
-   /// DiagnosticsEngine object. 
-   DiagnosticsEngine &Diag; 
-   
-   FileManager &FileMgr; 
-   
-   mutable llvm::BumpPtrAllocator ContentCacheAlloc; 
-   
-   /// Memoized information about all of the files tracked by this 
-   /// SourceManager. 
-   /// 
-   /// This map allows us to merge ContentCache entries based 
-   /// on their FileEntry*.  All ContentCache objects will thus have unique, 
-   /// non-null, FileEntry pointers. 
-   llvm::DenseMap<const FileEntry*, SrcMgr::ContentCache*> FileInfos; 
-   
-   /// True if the ContentCache for files that are overridden by other 
-   /// files, should report the original file name. Defaults to true. 
-   bool OverridenFilesKeepOriginalName = true; 
-   
-   /// True if non-system source files should be treated as volatile 
-   /// (likely to change while trying to use them). Defaults to false. 
-   bool UserFilesAreVolatile; 
-   
-   /// True if all files read during this compilation should be treated 
-   /// as transient (may not be present in later compilations using a module 
-   /// file created from this compilation). Defaults to false. 
-   bool FilesAreTransient = false; 
-   
-   struct OverriddenFilesInfoTy { 
-     /// Files that have been overridden with the contents from another 
-     /// file. 
-     llvm::DenseMap<const FileEntry *, FileEntryRef> OverriddenFiles; 
-   
-     /// Files that were overridden with a memory buffer. 
-     llvm::DenseSet<const FileEntry *> OverriddenFilesWithBuffer; 
-   }; 
-   
-   /// Lazily create the object keeping overridden files info, since 
-   /// it is uncommonly used. 
-   std::unique_ptr<OverriddenFilesInfoTy> OverriddenFilesInfo; 
-   
-   OverriddenFilesInfoTy &getOverriddenFilesInfo() { 
-     if (!OverriddenFilesInfo) 
-       OverriddenFilesInfo.reset(new OverriddenFilesInfoTy); 
-     return *OverriddenFilesInfo; 
-   } 
-   
-   /// Information about various memory buffers that we have read in. 
-   /// 
-   /// All FileEntry* within the stored ContentCache objects are NULL, 
-   /// as they do not refer to a file. 
-   std::vector<SrcMgr::ContentCache*> MemBufferInfos; 
-   
-   /// The table of SLocEntries that are local to this module. 
-   /// 
-   /// Positive FileIDs are indexes into this table. Entry 0 indicates an invalid 
-   /// expansion. 
-   SmallVector<SrcMgr::SLocEntry, 0> LocalSLocEntryTable; 
-   
-   /// The table of SLocEntries that are loaded from other modules. 
-   /// 
-   /// Negative FileIDs are indexes into this table. To get from ID to an index, 
-   /// use (-ID - 2). 
-   SmallVector<SrcMgr::SLocEntry, 0> LoadedSLocEntryTable; 
-   
-   /// The starting offset of the next local SLocEntry. 
-   /// 
-   /// This is LocalSLocEntryTable.back().Offset + the size of that entry. 
-   SourceLocation::UIntTy NextLocalOffset; 
-   
-   /// The starting offset of the latest batch of loaded SLocEntries. 
-   /// 
-   /// This is LoadedSLocEntryTable.back().Offset, except that that entry might 
-   /// not have been loaded, so that value would be unknown. 
-   SourceLocation::UIntTy CurrentLoadedOffset; 
-   
-   /// The highest possible offset is 2^31-1 (2^63-1 for 64-bit source 
-   /// locations), so CurrentLoadedOffset starts at 2^31 (2^63 resp.). 
-   static const SourceLocation::UIntTy MaxLoadedOffset = 
-       1ULL << (8 * sizeof(SourceLocation::UIntTy) - 1); 
-   
-   /// A bitmap that indicates whether the entries of LoadedSLocEntryTable 
-   /// have already been loaded from the external source. 
-   /// 
-   /// Same indexing as LoadedSLocEntryTable. 
-   llvm::BitVector SLocEntryLoaded; 
-   
-   /// An external source for source location entries. 
-   ExternalSLocEntrySource *ExternalSLocEntries = nullptr; 
-   
-   /// A one-entry cache to speed up getFileID. 
-   /// 
-   /// LastFileIDLookup records the last FileID looked up or created, because it 
-   /// is very common to look up many tokens from the same file. 
-   mutable FileID LastFileIDLookup; 
-   
-   /// Holds information for \#line directives. 
-   /// 
-   /// This is referenced by indices from SLocEntryTable. 
-   std::unique_ptr<LineTableInfo> LineTable; 
-   
-   /// These ivars serve as a cache used in the getLineNumber 
-   /// method which is used to speedup getLineNumber calls to nearby locations. 
-   mutable FileID LastLineNoFileIDQuery; 
-   mutable const SrcMgr::ContentCache *LastLineNoContentCache; 
-   mutable unsigned LastLineNoFilePos; 
-   mutable unsigned LastLineNoResult; 
-   
-   /// The file ID for the main source file of the translation unit. 
-   FileID MainFileID; 
-   
-   /// The file ID for the precompiled preamble there is one. 
-   FileID PreambleFileID; 
-   
-   // Statistics for -print-stats. 
-   mutable unsigned NumLinearScans = 0; 
-   mutable unsigned NumBinaryProbes = 0; 
-   
-   /// Associates a FileID with its "included/expanded in" decomposed 
-   /// location. 
-   /// 
-   /// Used to cache results from and speed-up \c getDecomposedIncludedLoc 
-   /// function. 
-   mutable llvm::DenseMap<FileID, std::pair<FileID, unsigned>> IncludedLocMap; 
-   
-   /// The key value into the IsBeforeInTUCache table. 
-   using IsBeforeInTUCacheKey = std::pair<FileID, FileID>; 
-   
-   /// The IsBeforeInTranslationUnitCache is a mapping from FileID pairs 
-   /// to cache results. 
-   using InBeforeInTUCache = 
-       llvm::DenseMap<IsBeforeInTUCacheKey, InBeforeInTUCacheEntry>; 
-   
-   /// Cache results for the isBeforeInTranslationUnit method. 
-   mutable InBeforeInTUCache IBTUCache; 
-   mutable InBeforeInTUCacheEntry IBTUCacheOverflow; 
-   
-   /// Return the cache entry for comparing the given file IDs 
-   /// for isBeforeInTranslationUnit. 
-   InBeforeInTUCacheEntry &getInBeforeInTUCache(FileID LFID, FileID RFID) const; 
-   
-   // Cache for the "fake" buffer used for error-recovery purposes. 
-   mutable std::unique_ptr<llvm::MemoryBuffer> FakeBufferForRecovery; 
-   
-   mutable std::unique_ptr<SrcMgr::ContentCache> FakeContentCacheForRecovery; 
-   
-   mutable std::unique_ptr<SrcMgr::SLocEntry> FakeSLocEntryForRecovery; 
-   
-   /// Lazily computed map of macro argument chunks to their expanded 
-   /// source location. 
-   using MacroArgsMap = std::map<unsigned, SourceLocation>; 
-   
-   mutable llvm::DenseMap<FileID, std::unique_ptr<MacroArgsMap>> 
-       MacroArgsCacheMap; 
-   
-   /// The stack of modules being built, which is used to detect 
-   /// cycles in the module dependency graph as modules are being built, as 
-   /// well as to describe why we're rebuilding a particular module. 
-   /// 
-   /// There is no way to set this value from the command line. If we ever need 
-   /// to do so (e.g., if on-demand module construction moves out-of-process), 
-   /// we can add a cc1-level option to do so. 
-   SmallVector<std::pair<std::string, FullSourceLoc>, 2> StoredModuleBuildStack; 
-   
- public: 
-   SourceManager(DiagnosticsEngine &Diag, FileManager &FileMgr, 
-                 bool UserFilesAreVolatile = false); 
-   explicit SourceManager(const SourceManager &) = delete; 
-   SourceManager &operator=(const SourceManager &) = delete; 
-   ~SourceManager(); 
-   
-   void clearIDTables(); 
-   
-   /// Initialize this source manager suitably to replay the compilation 
-   /// described by \p Old. Requires that \p Old outlive \p *this. 
-   void initializeForReplay(const SourceManager &Old); 
-   
-   DiagnosticsEngine &getDiagnostics() const { return Diag; } 
-   
-   FileManager &getFileManager() const { return FileMgr; } 
-   
-   /// Set true if the SourceManager should report the original file name 
-   /// for contents of files that were overridden by other files. Defaults to 
-   /// true. 
-   void setOverridenFilesKeepOriginalName(bool value) { 
-     OverridenFilesKeepOriginalName = value; 
-   } 
-   
-   /// True if non-system source files should be treated as volatile 
-   /// (likely to change while trying to use them). 
-   bool userFilesAreVolatile() const { return UserFilesAreVolatile; } 
-   
-   /// Retrieve the module build stack. 
-   ModuleBuildStack getModuleBuildStack() const { 
-     return StoredModuleBuildStack; 
-   } 
-   
-   /// Set the module build stack. 
-   void setModuleBuildStack(ModuleBuildStack stack) { 
-     StoredModuleBuildStack.clear(); 
-     StoredModuleBuildStack.append(stack.begin(), stack.end()); 
-   } 
-   
-   /// Push an entry to the module build stack. 
-   void pushModuleBuildStack(StringRef moduleName, FullSourceLoc importLoc) { 
-     StoredModuleBuildStack.push_back(std::make_pair(moduleName.str(),importLoc)); 
-   } 
-   
-   //===--------------------------------------------------------------------===// 
-   // MainFileID creation and querying methods. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Returns the FileID of the main source file. 
-   FileID getMainFileID() const { return MainFileID; } 
-   
-   /// Set the file ID for the main source file. 
-   void setMainFileID(FileID FID) { 
-     MainFileID = FID; 
-   } 
-   
-   /// Returns true when the given FileEntry corresponds to the main file. 
-   /// 
-   /// The main file should be set prior to calling this function. 
-   bool isMainFile(const FileEntry &SourceFile); 
-   
-   /// Set the file ID for the precompiled preamble. 
-   void setPreambleFileID(FileID Preamble) { 
-     assert(PreambleFileID.isInvalid() && "PreambleFileID already set!"); 
-     PreambleFileID = Preamble; 
-   } 
-   
-   /// Get the file ID for the precompiled preamble if there is one. 
-   FileID getPreambleFileID() const { return PreambleFileID; } 
-   
-   //===--------------------------------------------------------------------===// 
-   // Methods to create new FileID's and macro expansions. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Create a new FileID that represents the specified file 
-   /// being \#included from the specified IncludePosition. 
-   /// 
-   /// This translates NULL into standard input. 
-   FileID createFileID(const FileEntry *SourceFile, SourceLocation IncludePos, 
-                       SrcMgr::CharacteristicKind FileCharacter, 
-                       int LoadedID = 0, 
-                       SourceLocation::UIntTy LoadedOffset = 0); 
-   
-   FileID createFileID(FileEntryRef SourceFile, SourceLocation IncludePos, 
-                       SrcMgr::CharacteristicKind FileCharacter, 
-                       int LoadedID = 0, 
-                       SourceLocation::UIntTy LoadedOffset = 0); 
-   
-   /// Create a new FileID that represents the specified memory buffer. 
-   /// 
-   /// This does no caching of the buffer and takes ownership of the 
-   /// MemoryBuffer, so only pass a MemoryBuffer to this once. 
-   FileID createFileID(std::unique_ptr<llvm::MemoryBuffer> Buffer, 
-                       SrcMgr::CharacteristicKind FileCharacter = SrcMgr::C_User, 
-                       int LoadedID = 0, SourceLocation::UIntTy LoadedOffset = 0, 
-                       SourceLocation IncludeLoc = SourceLocation()); 
-   
-   /// Create a new FileID that represents the specified memory buffer. 
-   /// 
-   /// This does not take ownership of the MemoryBuffer. The memory buffer must 
-   /// outlive the SourceManager. 
-   FileID createFileID(const llvm::MemoryBufferRef &Buffer, 
-                       SrcMgr::CharacteristicKind FileCharacter = SrcMgr::C_User, 
-                       int LoadedID = 0, SourceLocation::UIntTy LoadedOffset = 0, 
-                       SourceLocation IncludeLoc = SourceLocation()); 
-   
-   /// Get the FileID for \p SourceFile if it exists. Otherwise, create a 
-   /// new FileID for the \p SourceFile. 
-   FileID getOrCreateFileID(const FileEntry *SourceFile, 
-                            SrcMgr::CharacteristicKind FileCharacter); 
-   
-   /// Creates an expansion SLocEntry for the substitution of an argument into a 
-   /// function-like macro's body. Returns the start of the expansion. 
-   /// 
-   /// The macro argument was written at \p SpellingLoc with length \p Length. 
-   /// \p ExpansionLoc is the parameter name in the (expanded) macro body. 
-   SourceLocation createMacroArgExpansionLoc(SourceLocation SpellingLoc, 
-                                             SourceLocation ExpansionLoc, 
-                                             unsigned Length); 
-   
-   /// Creates an expansion SLocEntry for a macro use. Returns its start. 
-   /// 
-   /// The macro body begins at \p SpellingLoc with length \p Length. 
-   /// The macro use spans [ExpansionLocStart, ExpansionLocEnd]. 
-   SourceLocation createExpansionLoc(SourceLocation SpellingLoc, 
-                                     SourceLocation ExpansionLocStart, 
-                                     SourceLocation ExpansionLocEnd, 
-                                     unsigned Length, 
-                                     bool ExpansionIsTokenRange = true, 
-                                     int LoadedID = 0, 
-                                     SourceLocation::UIntTy LoadedOffset = 0); 
-   
-   /// Return a new SourceLocation that encodes that the token starting 
-   /// at \p TokenStart ends prematurely at \p TokenEnd. 
-   SourceLocation createTokenSplitLoc(SourceLocation SpellingLoc, 
-                                      SourceLocation TokenStart, 
-                                      SourceLocation TokenEnd); 
-   
-   /// Retrieve the memory buffer associated with the given file. 
-   /// 
-   /// Returns std::nullopt if the buffer is not valid. 
-   std::optional<llvm::MemoryBufferRef> 
-   getMemoryBufferForFileOrNone(const FileEntry *File); 
-   
-   /// Retrieve the memory buffer associated with the given file. 
-   /// 
-   /// Returns a fake buffer if there isn't a real one. 
-   llvm::MemoryBufferRef getMemoryBufferForFileOrFake(const FileEntry *File) { 
-     if (auto B = getMemoryBufferForFileOrNone(File)) 
-       return *B; 
-     return getFakeBufferForRecovery(); 
-   } 
-   
-   /// Override the contents of the given source file by providing an 
-   /// already-allocated buffer. 
-   /// 
-   /// \param SourceFile the source file whose contents will be overridden. 
-   /// 
-   /// \param Buffer the memory buffer whose contents will be used as the 
-   /// data in the given source file. 
-   void overrideFileContents(const FileEntry *SourceFile, 
-                             const llvm::MemoryBufferRef &Buffer) { 
-     overrideFileContents(SourceFile, llvm::MemoryBuffer::getMemBuffer(Buffer)); 
-   } 
-   
-   /// Override the contents of the given source file by providing an 
-   /// already-allocated buffer. 
-   /// 
-   /// \param SourceFile the source file whose contents will be overridden. 
-   /// 
-   /// \param Buffer the memory buffer whose contents will be used as the 
-   /// data in the given source file. 
-   void overrideFileContents(const FileEntry *SourceFile, 
-                             std::unique_ptr<llvm::MemoryBuffer> Buffer); 
-   void overrideFileContents(FileEntryRef SourceFile, 
-                             std::unique_ptr<llvm::MemoryBuffer> Buffer) { 
-     overrideFileContents(&SourceFile.getFileEntry(), std::move(Buffer)); 
-   } 
-   
-   /// Override the given source file with another one. 
-   /// 
-   /// \param SourceFile the source file which will be overridden. 
-   /// 
-   /// \param NewFile the file whose contents will be used as the 
-   /// data instead of the contents of the given source file. 
-   void overrideFileContents(const FileEntry *SourceFile, FileEntryRef NewFile); 
-   
-   /// Returns true if the file contents have been overridden. 
-   bool isFileOverridden(const FileEntry *File) const { 
-     if (OverriddenFilesInfo) { 
-       if (OverriddenFilesInfo->OverriddenFilesWithBuffer.count(File)) 
-         return true; 
-       if (OverriddenFilesInfo->OverriddenFiles.find(File) != 
-           OverriddenFilesInfo->OverriddenFiles.end()) 
-         return true; 
-     } 
-     return false; 
-   } 
-   
-   /// Bypass the overridden contents of a file.  This creates a new FileEntry 
-   /// and initializes the content cache for it.  Returns std::nullopt if there 
-   /// is no such file in the filesystem. 
-   /// 
-   /// This should be called before parsing has begun. 
-   OptionalFileEntryRef bypassFileContentsOverride(FileEntryRef File); 
-   
-   /// Specify that a file is transient. 
-   void setFileIsTransient(const FileEntry *SourceFile); 
-   
-   /// Specify that all files that are read during this compilation are 
-   /// transient. 
-   void setAllFilesAreTransient(bool Transient) { 
-     FilesAreTransient = Transient; 
-   } 
-   
-   //===--------------------------------------------------------------------===// 
-   // FileID manipulation methods. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Return the buffer for the specified FileID. 
-   /// 
-   /// If there is an error opening this buffer the first time, return 
-   /// std::nullopt. 
-   std::optional<llvm::MemoryBufferRef> 
-   getBufferOrNone(FileID FID, SourceLocation Loc = SourceLocation()) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return Entry->getFile().getContentCache().getBufferOrNone( 
-           Diag, getFileManager(), Loc); 
-     return std::nullopt; 
-   } 
-   
-   /// Return the buffer for the specified FileID. 
-   /// 
-   /// If there is an error opening this buffer the first time, this 
-   /// manufactures a temporary buffer and returns it. 
-   llvm::MemoryBufferRef 
-   getBufferOrFake(FileID FID, SourceLocation Loc = SourceLocation()) const { 
-     if (auto B = getBufferOrNone(FID, Loc)) 
-       return *B; 
-     return getFakeBufferForRecovery(); 
-   } 
-   
-   /// Returns the FileEntry record for the provided FileID. 
-   const FileEntry *getFileEntryForID(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return Entry->getFile().getContentCache().OrigEntry; 
-     return nullptr; 
-   } 
-   
-   /// Returns the FileEntryRef for the provided FileID. 
-   OptionalFileEntryRef getFileEntryRefForID(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return Entry->getFile().getContentCache().OrigEntry; 
-     return std::nullopt; 
-   } 
-   
-   /// Returns the filename for the provided FileID, unless it's a built-in 
-   /// buffer that's not represented by a filename. 
-   /// 
-   /// Returns std::nullopt for non-files and built-in files. 
-   std::optional<StringRef> getNonBuiltinFilenameForID(FileID FID) const; 
-   
-   /// Returns the FileEntry record for the provided SLocEntry. 
-   const FileEntry *getFileEntryForSLocEntry(const SrcMgr::SLocEntry &sloc) const 
-   { 
-     return sloc.getFile().getContentCache().OrigEntry; 
-   } 
-   
-   /// Return a StringRef to the source buffer data for the 
-   /// specified FileID. 
-   /// 
-   /// \param FID The file ID whose contents will be returned. 
-   /// \param Invalid If non-NULL, will be set true if an error occurred. 
-   StringRef getBufferData(FileID FID, bool *Invalid = nullptr) const; 
-   
-   /// Return a StringRef to the source buffer data for the 
-   /// specified FileID, returning std::nullopt if invalid. 
-   /// 
-   /// \param FID The file ID whose contents will be returned. 
-   std::optional<StringRef> getBufferDataOrNone(FileID FID) const; 
-   
-   /// Return a StringRef to the source buffer data for the 
-   /// specified FileID, returning std::nullopt if it's not yet loaded. 
-   /// 
-   /// \param FID The file ID whose contents will be returned. 
-   std::optional<StringRef> getBufferDataIfLoaded(FileID FID) const; 
-   
-   /// Get the number of FileIDs (files and macros) that were created 
-   /// during preprocessing of \p FID, including it. 
-   unsigned getNumCreatedFIDsForFileID(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return Entry->getFile().NumCreatedFIDs; 
-     return 0; 
-   } 
-   
-   /// Set the number of FileIDs (files and macros) that were created 
-   /// during preprocessing of \p FID, including it. 
-   void setNumCreatedFIDsForFileID(FileID FID, unsigned NumFIDs, 
-                                   bool Force = false) const { 
-     auto *Entry = getSLocEntryForFile(FID); 
-     if (!Entry) 
-       return; 
-     assert((Force || Entry->getFile().NumCreatedFIDs == 0) && "Already set!"); 
-     const_cast<SrcMgr::FileInfo &>(Entry->getFile()).NumCreatedFIDs = NumFIDs; 
-   } 
-   
-   //===--------------------------------------------------------------------===// 
-   // SourceLocation manipulation methods. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Return the FileID for a SourceLocation. 
-   /// 
-   /// This is a very hot method that is used for all SourceManager queries 
-   /// that start with a SourceLocation object.  It is responsible for finding 
-   /// the entry in SLocEntryTable which contains the specified location. 
-   /// 
-   FileID getFileID(SourceLocation SpellingLoc) const { 
-     return getFileID(SpellingLoc.getOffset()); 
-   } 
-   
-   /// Return the filename of the file containing a SourceLocation. 
-   StringRef getFilename(SourceLocation SpellingLoc) const; 
-   
-   /// Return the source location corresponding to the first byte of 
-   /// the specified file. 
-   SourceLocation getLocForStartOfFile(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return SourceLocation::getFileLoc(Entry->getOffset()); 
-     return SourceLocation(); 
-   } 
-   
-   /// Return the source location corresponding to the last byte of the 
-   /// specified file. 
-   SourceLocation getLocForEndOfFile(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return SourceLocation::getFileLoc(Entry->getOffset() + 
-                                         getFileIDSize(FID)); 
-     return SourceLocation(); 
-   } 
-   
-   /// Returns the include location if \p FID is a \#include'd file 
-   /// otherwise it returns an invalid location. 
-   SourceLocation getIncludeLoc(FileID FID) const { 
-     if (auto *Entry = getSLocEntryForFile(FID)) 
-       return Entry->getFile().getIncludeLoc(); 
-     return SourceLocation(); 
-   } 
-   
-   // Returns the import location if the given source location is 
-   // located within a module, or an invalid location if the source location 
-   // is within the current translation unit. 
-   std::pair<SourceLocation, StringRef> 
-   getModuleImportLoc(SourceLocation Loc) const { 
-     FileID FID = getFileID(Loc); 
-   
-     // Positive file IDs are in the current translation unit, and -1 is a 
-     // placeholder. 
-     if (FID.ID >= -1) 
-       return std::make_pair(SourceLocation(), ""); 
-   
-     return ExternalSLocEntries->getModuleImportLoc(FID.ID); 
-   } 
-   
-   /// Given a SourceLocation object \p Loc, return the expansion 
-   /// location referenced by the ID. 
-   SourceLocation getExpansionLoc(SourceLocation Loc) const { 
-     // Handle the non-mapped case inline, defer to out of line code to handle 
-     // expansions. 
-     if (Loc.isFileID()) return Loc; 
-     return getExpansionLocSlowCase(Loc); 
-   } 
-   
-   /// Given \p Loc, if it is a macro location return the expansion 
-   /// location or the spelling location, depending on if it comes from a 
-   /// macro argument or not. 
-   SourceLocation getFileLoc(SourceLocation Loc) const { 
-     if (Loc.isFileID()) return Loc; 
-     return getFileLocSlowCase(Loc); 
-   } 
-   
-   /// Return the start/end of the expansion information for an 
-   /// expansion location. 
-   /// 
-   /// \pre \p Loc is required to be an expansion location. 
-   CharSourceRange getImmediateExpansionRange(SourceLocation Loc) const; 
-   
-   /// Given a SourceLocation object, return the range of 
-   /// tokens covered by the expansion in the ultimate file. 
-   CharSourceRange getExpansionRange(SourceLocation Loc) const; 
-   
-   /// Given a SourceRange object, return the range of 
-   /// tokens or characters covered by the expansion in the ultimate file. 
-   CharSourceRange getExpansionRange(SourceRange Range) const { 
-     SourceLocation Begin = getExpansionRange(Range.getBegin()).getBegin(); 
-     CharSourceRange End = getExpansionRange(Range.getEnd()); 
-     return CharSourceRange(SourceRange(Begin, End.getEnd()), 
-                            End.isTokenRange()); 
-   } 
-   
-   /// Given a CharSourceRange object, return the range of 
-   /// tokens or characters covered by the expansion in the ultimate file. 
-   CharSourceRange getExpansionRange(CharSourceRange Range) const { 
-     CharSourceRange Expansion = getExpansionRange(Range.getAsRange()); 
-     if (Expansion.getEnd() == Range.getEnd()) 
-       Expansion.setTokenRange(Range.isTokenRange()); 
-     return Expansion; 
-   } 
-   
-   /// Given a SourceLocation object, return the spelling 
-   /// location referenced by the ID. 
-   /// 
-   /// This is the place where the characters that make up the lexed token 
-   /// can be found. 
-   SourceLocation getSpellingLoc(SourceLocation Loc) const { 
-     // Handle the non-mapped case inline, defer to out of line code to handle 
-     // expansions. 
-     if (Loc.isFileID()) return Loc; 
-     return getSpellingLocSlowCase(Loc); 
-   } 
-   
-   /// Given a SourceLocation object, return the spelling location 
-   /// referenced by the ID. 
-   /// 
-   /// This is the first level down towards the place where the characters 
-   /// that make up the lexed token can be found.  This should not generally 
-   /// be used by clients. 
-   SourceLocation getImmediateSpellingLoc(SourceLocation Loc) const; 
-   
-   /// Form a SourceLocation from a FileID and Offset pair. 
-   SourceLocation getComposedLoc(FileID FID, unsigned Offset) const { 
-     auto *Entry = getSLocEntryOrNull(FID); 
-     if (!Entry) 
-       return SourceLocation(); 
-   
-     SourceLocation::UIntTy GlobalOffset = Entry->getOffset() + Offset; 
-     return Entry->isFile() ? SourceLocation::getFileLoc(GlobalOffset) 
-                            : SourceLocation::getMacroLoc(GlobalOffset); 
-   } 
-   
-   /// Decompose the specified location into a raw FileID + Offset pair. 
-   /// 
-   /// The first element is the FileID, the second is the offset from the 
-   /// start of the buffer of the location. 
-   std::pair<FileID, unsigned> getDecomposedLoc(SourceLocation Loc) const { 
-     FileID FID = getFileID(Loc); 
-     auto *Entry = getSLocEntryOrNull(FID); 
-     if (!Entry) 
-       return std::make_pair(FileID(), 0); 
-     return std::make_pair(FID, Loc.getOffset() - Entry->getOffset()); 
-   } 
-   
-   /// Decompose the specified location into a raw FileID + Offset pair. 
-   /// 
-   /// If the location is an expansion record, walk through it until we find 
-   /// the final location expanded. 
-   std::pair<FileID, unsigned> 
-   getDecomposedExpansionLoc(SourceLocation Loc) const { 
-     FileID FID = getFileID(Loc); 
-     auto *E = getSLocEntryOrNull(FID); 
-     if (!E) 
-       return std::make_pair(FileID(), 0); 
-   
-     unsigned Offset = Loc.getOffset()-E->getOffset(); 
-     if (Loc.isFileID()) 
-       return std::make_pair(FID, Offset); 
-   
-     return getDecomposedExpansionLocSlowCase(E); 
-   } 
-   
-   /// Decompose the specified location into a raw FileID + Offset pair. 
-   /// 
-   /// If the location is an expansion record, walk through it until we find 
-   /// its spelling record. 
-   std::pair<FileID, unsigned> 
-   getDecomposedSpellingLoc(SourceLocation Loc) const { 
-     FileID FID = getFileID(Loc); 
-     auto *E = getSLocEntryOrNull(FID); 
-     if (!E) 
-       return std::make_pair(FileID(), 0); 
-   
-     unsigned Offset = Loc.getOffset()-E->getOffset(); 
-     if (Loc.isFileID()) 
-       return std::make_pair(FID, Offset); 
-     return getDecomposedSpellingLocSlowCase(E, Offset); 
-   } 
-   
-   /// Returns the "included/expanded in" decomposed location of the given 
-   /// FileID. 
-   std::pair<FileID, unsigned> getDecomposedIncludedLoc(FileID FID) const; 
-   
-   /// Returns the offset from the start of the file that the 
-   /// specified SourceLocation represents. 
-   /// 
-   /// This is not very meaningful for a macro ID. 
-   unsigned getFileOffset(SourceLocation SpellingLoc) const { 
-     return getDecomposedLoc(SpellingLoc).second; 
-   } 
-   
-   /// Tests whether the given source location represents a macro 
-   /// argument's expansion into the function-like macro definition. 
-   /// 
-   /// \param StartLoc If non-null and function returns true, it is set to the 
-   /// start location of the macro argument expansion. 
-   /// 
-   /// Such source locations only appear inside of the expansion 
-   /// locations representing where a particular function-like macro was 
-   /// expanded. 
-   bool isMacroArgExpansion(SourceLocation Loc, 
-                            SourceLocation *StartLoc = nullptr) const; 
-   
-   /// Tests whether the given source location represents the expansion of 
-   /// a macro body. 
-   /// 
-   /// This is equivalent to testing whether the location is part of a macro 
-   /// expansion but not the expansion of an argument to a function-like macro. 
-   bool isMacroBodyExpansion(SourceLocation Loc) const; 
-   
-   /// Returns true if the given MacroID location points at the beginning 
-   /// of the immediate macro expansion. 
-   /// 
-   /// \param MacroBegin If non-null and function returns true, it is set to the 
-   /// begin location of the immediate macro expansion. 
-   bool isAtStartOfImmediateMacroExpansion(SourceLocation Loc, 
-                                     SourceLocation *MacroBegin = nullptr) const; 
-   
-   /// Returns true if the given MacroID location points at the character 
-   /// end of the immediate macro expansion. 
-   /// 
-   /// \param MacroEnd If non-null and function returns true, it is set to the 
-   /// character end location of the immediate macro expansion. 
-   bool 
-   isAtEndOfImmediateMacroExpansion(SourceLocation Loc, 
-                                    SourceLocation *MacroEnd = nullptr) const; 
-   
-   /// Returns true if \p Loc is inside the [\p Start, +\p Length) 
-   /// chunk of the source location address space. 
-   /// 
-   /// If it's true and \p RelativeOffset is non-null, it will be set to the 
-   /// relative offset of \p Loc inside the chunk. 
-   bool 
-   isInSLocAddrSpace(SourceLocation Loc, SourceLocation Start, unsigned Length, 
-                     SourceLocation::UIntTy *RelativeOffset = nullptr) const { 
-     assert(((Start.getOffset() < NextLocalOffset && 
-                Start.getOffset()+Length <= NextLocalOffset) || 
-             (Start.getOffset() >= CurrentLoadedOffset && 
-                 Start.getOffset()+Length < MaxLoadedOffset)) && 
-            "Chunk is not valid SLoc address space"); 
-     SourceLocation::UIntTy LocOffs = Loc.getOffset(); 
-     SourceLocation::UIntTy BeginOffs = Start.getOffset(); 
-     SourceLocation::UIntTy EndOffs = BeginOffs + Length; 
-     if (LocOffs >= BeginOffs && LocOffs < EndOffs) { 
-       if (RelativeOffset) 
-         *RelativeOffset = LocOffs - BeginOffs; 
-       return true; 
-     } 
-   
-     return false; 
-   } 
-   
-   /// Return true if both \p LHS and \p RHS are in the local source 
-   /// location address space or the loaded one. 
-   /// 
-   /// If it's true and \p RelativeOffset is non-null, it will be set to the 
-   /// offset of \p RHS relative to \p LHS. 
-   bool isInSameSLocAddrSpace(SourceLocation LHS, SourceLocation RHS, 
-                              SourceLocation::IntTy *RelativeOffset) const { 
-     SourceLocation::UIntTy LHSOffs = LHS.getOffset(), RHSOffs = RHS.getOffset(); 
-     bool LHSLoaded = LHSOffs >= CurrentLoadedOffset; 
-     bool RHSLoaded = RHSOffs >= CurrentLoadedOffset; 
-   
-     if (LHSLoaded == RHSLoaded) { 
-       if (RelativeOffset) 
-         *RelativeOffset = RHSOffs - LHSOffs; 
-       return true; 
-     } 
-   
-     return false; 
-   } 
-   
-   //===--------------------------------------------------------------------===// 
-   // Queries about the code at a SourceLocation. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Return a pointer to the start of the specified location 
-   /// in the appropriate spelling MemoryBuffer. 
-   /// 
-   /// \param Invalid If non-NULL, will be set \c true if an error occurs. 
-   const char *getCharacterData(SourceLocation SL, 
-                                bool *Invalid = nullptr) const; 
-   
-   /// Return the column # for the specified file position. 
-   /// 
-   /// This is significantly cheaper to compute than the line number.  This 
-   /// returns zero if the column number isn't known.  This may only be called 
-   /// on a file sloc, so you must choose a spelling or expansion location 
-   /// before calling this method. 
-   unsigned getColumnNumber(FileID FID, unsigned FilePos, 
-                            bool *Invalid = nullptr) const; 
-   unsigned getSpellingColumnNumber(SourceLocation Loc, 
-                                    bool *Invalid = nullptr) const; 
-   unsigned getExpansionColumnNumber(SourceLocation Loc, 
-                                     bool *Invalid = nullptr) const; 
-   unsigned getPresumedColumnNumber(SourceLocation Loc, 
-                                    bool *Invalid = nullptr) const; 
-   
-   /// Given a SourceLocation, return the spelling line number 
-   /// for the position indicated. 
-   /// 
-   /// This requires building and caching a table of line offsets for the 
-   /// MemoryBuffer, so this is not cheap: use only when about to emit a 
-   /// diagnostic. 
-   unsigned getLineNumber(FileID FID, unsigned FilePos, bool *Invalid = nullptr) const; 
-   unsigned getSpellingLineNumber(SourceLocation Loc, bool *Invalid = nullptr) const; 
-   unsigned getExpansionLineNumber(SourceLocation Loc, bool *Invalid = nullptr) const; 
-   unsigned getPresumedLineNumber(SourceLocation Loc, bool *Invalid = nullptr) const; 
-   
-   /// Return the filename or buffer identifier of the buffer the 
-   /// location is in. 
-   /// 
-   /// Note that this name does not respect \#line directives.  Use 
-   /// getPresumedLoc for normal clients. 
-   StringRef getBufferName(SourceLocation Loc, bool *Invalid = nullptr) const; 
-   
-   /// Return the file characteristic of the specified source 
-   /// location, indicating whether this is a normal file, a system 
-   /// header, or an "implicit extern C" system header. 
-   /// 
-   /// This state can be modified with flags on GNU linemarker directives like: 
-   /// \code 
-   ///   # 4 "foo.h" 3 
-   /// \endcode 
-   /// which changes all source locations in the current file after that to be 
-   /// considered to be from a system header. 
-   SrcMgr::CharacteristicKind getFileCharacteristic(SourceLocation Loc) const; 
-   
-   /// Returns the "presumed" location of a SourceLocation specifies. 
-   /// 
-   /// A "presumed location" can be modified by \#line or GNU line marker 
-   /// directives.  This provides a view on the data that a user should see 
-   /// in diagnostics, for example. 
-   /// 
-   /// Note that a presumed location is always given as the expansion point of 
-   /// an expansion location, not at the spelling location. 
-   /// 
-   /// \returns The presumed location of the specified SourceLocation. If the 
-   /// presumed location cannot be calculated (e.g., because \p Loc is invalid 
-   /// or the file containing \p Loc has changed on disk), returns an invalid 
-   /// presumed location. 
-   PresumedLoc getPresumedLoc(SourceLocation Loc, 
-                              bool UseLineDirectives = true) const; 
-   
-   /// Returns whether the PresumedLoc for a given SourceLocation is 
-   /// in the main file. 
-   /// 
-   /// This computes the "presumed" location for a SourceLocation, then checks 
-   /// whether it came from a file other than the main file. This is different 
-   /// from isWrittenInMainFile() because it takes line marker directives into 
-   /// account. 
-   bool isInMainFile(SourceLocation Loc) const; 
-   
-   /// Returns true if the spelling locations for both SourceLocations 
-   /// are part of the same file buffer. 
-   /// 
-   /// This check ignores line marker directives. 
-   bool isWrittenInSameFile(SourceLocation Loc1, SourceLocation Loc2) const { 
-     return getFileID(Loc1) == getFileID(Loc2); 
-   } 
-   
-   /// Returns true if the spelling location for the given location 
-   /// is in the main file buffer. 
-   /// 
-   /// This check ignores line marker directives. 
-   bool isWrittenInMainFile(SourceLocation Loc) const { 
-     return getFileID(Loc) == getMainFileID(); 
-   } 
-   
-   /// Returns whether \p Loc is located in a <built-in> file. 
-   bool isWrittenInBuiltinFile(SourceLocation Loc) const { 
-     PresumedLoc Presumed = getPresumedLoc(Loc); 
-     if (Presumed.isInvalid()) 
-       return false; 
-     StringRef Filename(Presumed.getFilename()); 
-     return Filename.equals("<built-in>"); 
-   } 
-   
-   /// Returns whether \p Loc is located in a <command line> file. 
-   bool isWrittenInCommandLineFile(SourceLocation Loc) const { 
-     PresumedLoc Presumed = getPresumedLoc(Loc); 
-     if (Presumed.isInvalid()) 
-       return false; 
-     StringRef Filename(Presumed.getFilename()); 
-     return Filename.equals("<command line>"); 
-   } 
-   
-   /// Returns whether \p Loc is located in a <scratch space> file. 
-   bool isWrittenInScratchSpace(SourceLocation Loc) const { 
-     PresumedLoc Presumed = getPresumedLoc(Loc); 
-     if (Presumed.isInvalid()) 
-       return false; 
-     StringRef Filename(Presumed.getFilename()); 
-     return Filename.equals("<scratch space>"); 
-   } 
-   
-   /// Returns if a SourceLocation is in a system header. 
-   bool isInSystemHeader(SourceLocation Loc) const { 
-     if (Loc.isInvalid()) 
-       return false; 
-     return isSystem(getFileCharacteristic(Loc)); 
-   } 
-   
-   /// Returns if a SourceLocation is in an "extern C" system header. 
-   bool isInExternCSystemHeader(SourceLocation Loc) const { 
-     return getFileCharacteristic(Loc) == SrcMgr::C_ExternCSystem; 
-   } 
-   
-   /// Returns whether \p Loc is expanded from a macro in a system header. 
-   bool isInSystemMacro(SourceLocation loc) const { 
-     if (!loc.isMacroID()) 
-       return false; 
-   
-     // This happens when the macro is the result of a paste, in that case 
-     // its spelling is the scratch memory, so we take the parent context. 
-     // There can be several level of token pasting. 
-     if (isWrittenInScratchSpace(getSpellingLoc(loc))) { 
-       do { 
-         loc = getImmediateMacroCallerLoc(loc); 
-       } while (isWrittenInScratchSpace(getSpellingLoc(loc))); 
-       return isInSystemMacro(loc); 
-     } 
-   
-     return isInSystemHeader(getSpellingLoc(loc)); 
-   } 
-   
-   /// The size of the SLocEntry that \p FID represents. 
-   unsigned getFileIDSize(FileID FID) const; 
-   
-   /// Given a specific FileID, returns true if \p Loc is inside that 
-   /// FileID chunk and sets relative offset (offset of \p Loc from beginning 
-   /// of FileID) to \p relativeOffset. 
-   bool isInFileID(SourceLocation Loc, FileID FID, 
-                   unsigned *RelativeOffset = nullptr) const { 
-     SourceLocation::UIntTy Offs = Loc.getOffset(); 
-     if (isOffsetInFileID(FID, Offs)) { 
-       if (RelativeOffset) 
-         *RelativeOffset = Offs - getSLocEntry(FID).getOffset(); 
-       return true; 
-     } 
-   
-     return false; 
-   } 
-   
-   //===--------------------------------------------------------------------===// 
-   // Line Table Manipulation Routines 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Return the uniqued ID for the specified filename. 
-   unsigned getLineTableFilenameID(StringRef Str); 
-   
-   /// Add a line note to the line table for the FileID and offset 
-   /// specified by Loc. 
-   /// 
-   /// If FilenameID is -1, it is considered to be unspecified. 
-   void AddLineNote(SourceLocation Loc, unsigned LineNo, int FilenameID, 
-                    bool IsFileEntry, bool IsFileExit, 
-                    SrcMgr::CharacteristicKind FileKind); 
-   
-   /// Determine if the source manager has a line table. 
-   bool hasLineTable() const { return LineTable != nullptr; } 
-   
-   /// Retrieve the stored line table. 
-   LineTableInfo &getLineTable(); 
-   
-   //===--------------------------------------------------------------------===// 
-   // Queries for performance analysis. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Return the total amount of physical memory allocated by the 
-   /// ContentCache allocator. 
-   size_t getContentCacheSize() const { 
-     return ContentCacheAlloc.getTotalMemory(); 
-   } 
-   
-   struct MemoryBufferSizes { 
-     const size_t malloc_bytes; 
-     const size_t mmap_bytes; 
-   
-     MemoryBufferSizes(size_t malloc_bytes, size_t mmap_bytes) 
-       : malloc_bytes(malloc_bytes), mmap_bytes(mmap_bytes) {} 
-   }; 
-   
-   /// Return the amount of memory used by memory buffers, breaking down 
-   /// by heap-backed versus mmap'ed memory. 
-   MemoryBufferSizes getMemoryBufferSizes() const; 
-   
-   /// Return the amount of memory used for various side tables and 
-   /// data structures in the SourceManager. 
-   size_t getDataStructureSizes() const; 
-   
-   //===--------------------------------------------------------------------===// 
-   // Other miscellaneous methods. 
-   //===--------------------------------------------------------------------===// 
-   
-   /// Get the source location for the given file:line:col triplet. 
-   /// 
-   /// If the source file is included multiple times, the source location will 
-   /// be based upon the first inclusion. 
-   SourceLocation translateFileLineCol(const FileEntry *SourceFile, 
-                                       unsigned Line, unsigned Col) const; 
-   
-   /// Get the FileID for the given file. 
-   /// 
-   /// If the source file is included multiple times, the FileID will be the 
-   /// first inclusion. 
-   FileID translateFile(const FileEntry *SourceFile) const; 
-   FileID translateFile(FileEntryRef SourceFile) const { 
-     return translateFile(&SourceFile.getFileEntry()); 
-   } 
-   
-   /// Get the source location in \p FID for the given line:col. 
-   /// Returns null location if \p FID is not a file SLocEntry. 
-   SourceLocation translateLineCol(FileID FID, 
-                                   unsigned Line, unsigned Col) const; 
-   
-   /// If \p Loc points inside a function macro argument, the returned 
-   /// location will be the macro location in which the argument was expanded. 
-   /// If a macro argument is used multiple times, the expanded location will 
-   /// be at the first expansion of the argument. 
-   /// e.g. 
-   ///   MY_MACRO(foo); 
-   ///             ^ 
-   /// Passing a file location pointing at 'foo', will yield a macro location 
-   /// where 'foo' was expanded into. 
-   SourceLocation getMacroArgExpandedLocation(SourceLocation Loc) const; 
-   
-   /// Determines the order of 2 source locations in the translation unit. 
-   /// 
-   /// \returns true if LHS source location comes before RHS, false otherwise. 
-   bool isBeforeInTranslationUnit(SourceLocation LHS, SourceLocation RHS) const; 
-   
-   /// Determines whether the two decomposed source location is in the 
-   ///        same translation unit. As a byproduct, it also calculates the order 
-   ///        of the source locations in case they are in the same TU. 
-   /// 
-   /// \returns Pair of bools the first component is true if the two locations 
-   ///          are in the same TU. The second bool is true if the first is true 
-   ///          and \p LOffs is before \p ROffs. 
-   std::pair<bool, bool> 
-   isInTheSameTranslationUnit(std::pair<FileID, unsigned> &LOffs, 
-                              std::pair<FileID, unsigned> &ROffs) const; 
-   
-   /// Determines the order of 2 source locations in the "source location 
-   /// address space". 
-   bool isBeforeInSLocAddrSpace(SourceLocation LHS, SourceLocation RHS) const { 
-     return isBeforeInSLocAddrSpace(LHS, RHS.getOffset()); 
-   } 
-   
-   /// Determines the order of a source location and a source location 
-   /// offset in the "source location address space". 
-   /// 
-   /// Note that we always consider source locations loaded from 
-   bool isBeforeInSLocAddrSpace(SourceLocation LHS, 
-                                SourceLocation::UIntTy RHS) const { 
-     SourceLocation::UIntTy LHSOffset = LHS.getOffset(); 
-     bool LHSLoaded = LHSOffset >= CurrentLoadedOffset; 
-     bool RHSLoaded = RHS >= CurrentLoadedOffset; 
-     if (LHSLoaded == RHSLoaded) 
-       return LHSOffset < RHS; 
-   
-     return LHSLoaded; 
-   } 
-   
-   /// Return true if the Point is within Start and End. 
-   bool isPointWithin(SourceLocation Location, SourceLocation Start, 
-                      SourceLocation End) const { 
-     return Location == Start || Location == End || 
-            (isBeforeInTranslationUnit(Start, Location) && 
-             isBeforeInTranslationUnit(Location, End)); 
-   } 
-   
-   // Iterators over FileInfos. 
-   using fileinfo_iterator = 
-       llvm::DenseMap<const FileEntry*, SrcMgr::ContentCache*>::const_iterator; 
-   
-   fileinfo_iterator fileinfo_begin() const { return FileInfos.begin(); } 
-   fileinfo_iterator fileinfo_end() const { return FileInfos.end(); } 
-   bool hasFileInfo(const FileEntry *File) const { 
-     return FileInfos.find(File) != FileInfos.end(); 
-   } 
-   
-   /// Print statistics to stderr. 
-   void PrintStats() const; 
-   
-   void dump() const; 
-   
-   // Produce notes describing the current source location address space usage. 
-   void noteSLocAddressSpaceUsage(DiagnosticsEngine &Diag, 
-                                  std::optional<unsigned> MaxNotes = 32) const; 
-   
-   /// Get the number of local SLocEntries we have. 
-   unsigned local_sloc_entry_size() const { return LocalSLocEntryTable.size(); } 
-   
-   /// Get a local SLocEntry. This is exposed for indexing. 
-   const SrcMgr::SLocEntry &getLocalSLocEntry(unsigned Index) const { 
-     assert(Index < LocalSLocEntryTable.size() && "Invalid index"); 
-     return LocalSLocEntryTable[Index]; 
-   } 
-   
-   /// Get the number of loaded SLocEntries we have. 
-   unsigned loaded_sloc_entry_size() const { return LoadedSLocEntryTable.size();} 
-   
-   /// Get a loaded SLocEntry. This is exposed for indexing. 
-   const SrcMgr::SLocEntry &getLoadedSLocEntry(unsigned Index, 
-                                               bool *Invalid = nullptr) const { 
-     assert(Index < LoadedSLocEntryTable.size() && "Invalid index"); 
-     if (SLocEntryLoaded[Index]) 
-       return LoadedSLocEntryTable[Index]; 
-     return loadSLocEntry(Index, Invalid); 
-   } 
-   
-   const SrcMgr::SLocEntry &getSLocEntry(FileID FID, 
-                                         bool *Invalid = nullptr) const { 
-     if (FID.ID == 0 || FID.ID == -1) { 
-       if (Invalid) *Invalid = true; 
-       return LocalSLocEntryTable[0]; 
-     } 
-     return getSLocEntryByID(FID.ID, Invalid); 
-   } 
-   
-   SourceLocation::UIntTy getNextLocalOffset() const { return NextLocalOffset; } 
-   
-   void setExternalSLocEntrySource(ExternalSLocEntrySource *Source) { 
-     assert(LoadedSLocEntryTable.empty() && 
-            "Invalidating existing loaded entries"); 
-     ExternalSLocEntries = Source; 
-   } 
-   
-   /// Allocate a number of loaded SLocEntries, which will be actually 
-   /// loaded on demand from the external source. 
-   /// 
-   /// NumSLocEntries will be allocated, which occupy a total of TotalSize space 
-   /// in the global source view. The lowest ID and the base offset of the 
-   /// entries will be returned. 
-   std::pair<int, SourceLocation::UIntTy> 
-   AllocateLoadedSLocEntries(unsigned NumSLocEntries, 
-                             SourceLocation::UIntTy TotalSize); 
-   
-   /// Returns true if \p Loc came from a PCH/Module. 
-   bool isLoadedSourceLocation(SourceLocation Loc) const { 
-     return isLoadedOffset(Loc.getOffset()); 
-   } 
-   
-   /// Returns true if \p Loc did not come from a PCH/Module. 
-   bool isLocalSourceLocation(SourceLocation Loc) const { 
-     return isLocalOffset(Loc.getOffset()); 
-   } 
-   
-   /// Returns true if \p FID came from a PCH/Module. 
-   bool isLoadedFileID(FileID FID) const { 
-     assert(FID.ID != -1 && "Using FileID sentinel value"); 
-     return FID.ID < 0; 
-   } 
-   
-   /// Returns true if \p FID did not come from a PCH/Module. 
-   bool isLocalFileID(FileID FID) const { 
-     return !isLoadedFileID(FID); 
-   } 
-   
-   /// Gets the location of the immediate macro caller, one level up the stack 
-   /// toward the initial macro typed into the source. 
-   SourceLocation getImmediateMacroCallerLoc(SourceLocation Loc) const { 
-     if (!Loc.isMacroID()) return Loc; 
-   
-     // When we have the location of (part of) an expanded parameter, its 
-     // spelling location points to the argument as expanded in the macro call, 
-     // and therefore is used to locate the macro caller. 
-     if (isMacroArgExpansion(Loc)) 
-       return getImmediateSpellingLoc(Loc); 
-   
-     // Otherwise, the caller of the macro is located where this macro is 
-     // expanded (while the spelling is part of the macro definition). 
-     return getImmediateExpansionRange(Loc).getBegin(); 
-   } 
-   
-   /// \return Location of the top-level macro caller. 
-   SourceLocation getTopMacroCallerLoc(SourceLocation Loc) const; 
-   
- private: 
-   friend class ASTReader; 
-   friend class ASTWriter; 
-   
-   llvm::MemoryBufferRef getFakeBufferForRecovery() const; 
-   SrcMgr::ContentCache &getFakeContentCacheForRecovery() const; 
-   
-   const SrcMgr::SLocEntry &loadSLocEntry(unsigned Index, bool *Invalid) const; 
-   
-   const SrcMgr::SLocEntry *getSLocEntryOrNull(FileID FID) const { 
-     bool Invalid = false; 
-     const SrcMgr::SLocEntry &Entry = getSLocEntry(FID, &Invalid); 
-     return Invalid ? nullptr : &Entry; 
-   } 
-   
-   const SrcMgr::SLocEntry *getSLocEntryForFile(FileID FID) const { 
-     if (auto *Entry = getSLocEntryOrNull(FID)) 
-       if (Entry->isFile()) 
-         return Entry; 
-     return nullptr; 
-   } 
-   
-   /// Get the entry with the given unwrapped FileID. 
-   /// Invalid will not be modified for Local IDs. 
-   const SrcMgr::SLocEntry &getSLocEntryByID(int ID, 
-                                             bool *Invalid = nullptr) const { 
-     assert(ID != -1 && "Using FileID sentinel value"); 
-     if (ID < 0) 
-       return getLoadedSLocEntryByID(ID, Invalid); 
-     return getLocalSLocEntry(static_cast<unsigned>(ID)); 
-   } 
-   
-   const SrcMgr::SLocEntry & 
-   getLoadedSLocEntryByID(int ID, bool *Invalid = nullptr) const { 
-     return getLoadedSLocEntry(static_cast<unsigned>(-ID - 2), Invalid); 
-   } 
-   
-   FileID getFileID(SourceLocation::UIntTy SLocOffset) const { 
-     // If our one-entry cache covers this offset, just return it. 
-     if (isOffsetInFileID(LastFileIDLookup, SLocOffset)) 
-       return LastFileIDLookup; 
-   
-     return getFileIDSlow(SLocOffset); 
-   } 
-   
-   bool isLocalOffset(SourceLocation::UIntTy SLocOffset) const { 
-     return SLocOffset < CurrentLoadedOffset; 
-   } 
-   
-   bool isLoadedOffset(SourceLocation::UIntTy SLocOffset) const { 
-     return SLocOffset >= CurrentLoadedOffset; 
-   } 
-   
-   /// Implements the common elements of storing an expansion info struct into 
-   /// the SLocEntry table and producing a source location that refers to it. 
-   SourceLocation 
-   createExpansionLocImpl(const SrcMgr::ExpansionInfo &Expansion, 
-                          unsigned Length, int LoadedID = 0, 
-                          SourceLocation::UIntTy LoadedOffset = 0); 
-   
-   /// Return true if the specified FileID contains the 
-   /// specified SourceLocation offset.  This is a very hot method. 
-   inline bool isOffsetInFileID(FileID FID, 
-                                SourceLocation::UIntTy SLocOffset) const { 
-     const SrcMgr::SLocEntry &Entry = getSLocEntry(FID); 
-     // If the entry is after the offset, it can't contain it. 
-     if (SLocOffset < Entry.getOffset()) return false; 
-   
-     // If this is the very last entry then it does. 
-     if (FID.ID == -2) 
-       return true; 
-   
-     // If it is the last local entry, then it does if the location is local. 
-     if (FID.ID+1 == static_cast<int>(LocalSLocEntryTable.size())) 
-       return SLocOffset < NextLocalOffset; 
-   
-     // Otherwise, the entry after it has to not include it. This works for both 
-     // local and loaded entries. 
-     return SLocOffset < getSLocEntryByID(FID.ID+1).getOffset(); 
-   } 
-   
-   /// Returns the previous in-order FileID or an invalid FileID if there 
-   /// is no previous one. 
-   FileID getPreviousFileID(FileID FID) const; 
-   
-   /// Returns the next in-order FileID or an invalid FileID if there is 
-   /// no next one. 
-   FileID getNextFileID(FileID FID) const; 
-   
-   /// Create a new fileID for the specified ContentCache and 
-   /// include position. 
-   /// 
-   /// This works regardless of whether the ContentCache corresponds to a 
-   /// file or some other input source. 
-   FileID createFileIDImpl(SrcMgr::ContentCache &File, StringRef Filename, 
-                           SourceLocation IncludePos, 
-                           SrcMgr::CharacteristicKind DirCharacter, int LoadedID, 
-                           SourceLocation::UIntTy LoadedOffset); 
-   
-   SrcMgr::ContentCache &getOrCreateContentCache(FileEntryRef SourceFile, 
-                                                 bool isSystemFile = false); 
-   
-   /// Create a new ContentCache for the specified  memory buffer. 
-   SrcMgr::ContentCache & 
-   createMemBufferContentCache(std::unique_ptr<llvm::MemoryBuffer> Buf); 
-   
-   FileID getFileIDSlow(SourceLocation::UIntTy SLocOffset) const; 
-   FileID getFileIDLocal(SourceLocation::UIntTy SLocOffset) const; 
-   FileID getFileIDLoaded(SourceLocation::UIntTy SLocOffset) const; 
-   
-   SourceLocation getExpansionLocSlowCase(SourceLocation Loc) const; 
-   SourceLocation getSpellingLocSlowCase(SourceLocation Loc) const; 
-   SourceLocation getFileLocSlowCase(SourceLocation Loc) const; 
-   
-   std::pair<FileID, unsigned> 
-   getDecomposedExpansionLocSlowCase(const SrcMgr::SLocEntry *E) const; 
-   std::pair<FileID, unsigned> 
-   getDecomposedSpellingLocSlowCase(const SrcMgr::SLocEntry *E, 
-                                    unsigned Offset) const; 
-   void computeMacroArgsCache(MacroArgsMap &MacroArgsCache, FileID FID) const; 
-   void associateFileChunkWithMacroArgExp(MacroArgsMap &MacroArgsCache, 
-                                          FileID FID, 
-                                          SourceLocation SpellLoc, 
-                                          SourceLocation ExpansionLoc, 
-                                          unsigned ExpansionLength) const; 
- }; 
-   
- /// Comparison function object. 
- template<typename T> 
- class BeforeThanCompare; 
-   
- /// Compare two source locations. 
- template<> 
- class BeforeThanCompare<SourceLocation> { 
-   SourceManager &SM; 
-   
- public: 
-   explicit BeforeThanCompare(SourceManager &SM) : SM(SM) {} 
-   
-   bool operator()(SourceLocation LHS, SourceLocation RHS) const { 
-     return SM.isBeforeInTranslationUnit(LHS, RHS); 
-   } 
- }; 
-   
- /// Compare two non-overlapping source ranges. 
- template<> 
- class BeforeThanCompare<SourceRange> { 
-   SourceManager &SM; 
-   
- public: 
-   explicit BeforeThanCompare(SourceManager &SM) : SM(SM) {} 
-   
-   bool operator()(SourceRange LHS, SourceRange RHS) const { 
-     return SM.isBeforeInTranslationUnit(LHS.getBegin(), RHS.getBegin()); 
-   } 
- }; 
-   
- /// SourceManager and necessary dependencies (e.g. VFS, FileManager) for a 
- /// single in-memorty file. 
- class SourceManagerForFile { 
- public: 
-   /// Creates SourceManager and necessary dependencies (e.g. VFS, FileManager). 
-   /// The main file in the SourceManager will be \p FileName with \p Content. 
-   SourceManagerForFile(StringRef FileName, StringRef Content); 
-   
-   SourceManager &get() { 
-     assert(SourceMgr); 
-     return *SourceMgr; 
-   } 
-   
- private: 
-   // The order of these fields are important - they should be in the same order 
-   // as they are created in `createSourceManagerForFile` so that they can be 
-   // deleted in the reverse order as they are created. 
-   std::unique_ptr<FileManager> FileMgr; 
-   std::unique_ptr<DiagnosticsEngine> Diagnostics; 
-   std::unique_ptr<SourceManager> SourceMgr; 
- }; 
-   
- } // namespace clang 
-   
- #endif // LLVM_CLANG_BASIC_SOURCEMANAGER_H 
-