1 files changed, 37 insertions, 11 deletions

diff --git a/include/clang/Basic/SourceManager.h b/include/clang/Basic/SourceManager.h
index 6a4be4609433..7a66117f2076 100644
--- a/include/clang/Basic/SourceManager.h
+++ b/include/clang/Basic/SourceManager.h
@@ -50,13 +50,20 @@ namespace SrcMgr {
     C_User, C_System, C_ExternCSystem
   };
 
-  /// ContentCache - Once instance of this struct is kept for every file
+  /// ContentCache - One instance of this struct is kept for every file
   /// loaded or used.  This object owns the MemoryBuffer object.
   class ContentCache {
+    enum CCFlags {
+      /// \brief Whether the buffer is invalid.
+      InvalidFlag = 0x01,
+      /// \brief Whether the buffer should not be freed on destruction.
+      DoNotFreeFlag = 0x02
+    };
+    
     /// Buffer - The actual buffer containing the characters from the input
     /// file.  This is owned by the ContentCache object.
-    /// The bit indicates whether the buffer is invalid.
-    mutable llvm::PointerIntPair<const llvm::MemoryBuffer *, 1, bool> Buffer;
+    /// The bits indicate indicates whether the buffer is invalid.
+    mutable llvm::PointerIntPair<const llvm::MemoryBuffer *, 2> Buffer;
 
   public:
     /// Reference to the file entry.  This reference does not own
@@ -103,11 +110,27 @@ namespace SrcMgr {
       Buffer.setPointer(B);
       Buffer.setInt(false);
     }
+    
+    /// \brief Get the underlying buffer, returning NULL if the buffer is not
+    /// yet available.
+    const llvm::MemoryBuffer *getRawBuffer() const {
+      return Buffer.getPointer();
+    }
 
     /// \brief Replace the existing buffer (which will be deleted)
     /// with the given buffer.
-    void replaceBuffer(const llvm::MemoryBuffer *B);
+    void replaceBuffer(const llvm::MemoryBuffer *B, bool DoNotFree = false);
 
+    /// \brief Determine whether the buffer itself is invalid.
+    bool isBufferInvalid() const {
+      return Buffer.getInt() & InvalidFlag;
+    }
+    
+    /// \brief Determine whether the buffer should be freed.
+    bool shouldFreeBuffer() const {
+      return (Buffer.getInt() & DoNotFreeFlag) == 0;
+    }
+    
     ContentCache(const FileEntry *Ent = 0)
       : Buffer(0, false), Entry(Ent), SourceLineCache(0), NumLines(0) {}
 
@@ -421,10 +444,9 @@ public:
   FileID getMainFileID() const { return MainFileID; }
 
   /// createMainFileID - Create the FileID for the main source file.
-  FileID createMainFileID(const FileEntry *SourceFile,
-                          SourceLocation IncludePos) {
+  FileID createMainFileID(const FileEntry *SourceFile) {
     assert(MainFileID.isInvalid() && "MainFileID already set!");
-    MainFileID = createFileID(SourceFile, IncludePos, SrcMgr::C_User);
+    MainFileID = createFileID(SourceFile, SourceLocation(), SrcMgr::C_User);
     return MainFileID;
   }
 
@@ -435,7 +457,7 @@ public:
   /// createFileID - Create a new FileID that represents the specified file
   /// being #included from the specified IncludePosition.  This returns 0 on
   /// error and translates NULL into standard input.
-  /// PreallocateID should be non-zero to specify which a pre-allocated,
+  /// PreallocateID should be non-zero to specify which pre-allocated,
   /// lazily computed source location is being filled in by this operation.
   FileID createFileID(const FileEntry *SourceFile, SourceLocation IncludePos,
                       SrcMgr::CharacteristicKind FileCharacter,
@@ -485,14 +507,18 @@ public:
   /// \brief Override the contents of the given source file by providing an
   /// already-allocated buffer.
   ///
-  /// \param SourceFile the source file whose contents will be override.
+  /// \param SourceFile the source file whose contents will be overriden.
   ///
   /// \param Buffer the memory buffer whose contents will be used as the
   /// data in the given source file.
   ///
+  /// \param DoNotFree If true, then the buffer will not be freed when the
+  /// source manager is destroyed.
+  ///
   /// \returns true if an error occurred, false otherwise.
   bool overrideFileContents(const FileEntry *SourceFile,
-                            const llvm::MemoryBuffer *Buffer);
+                            const llvm::MemoryBuffer *Buffer,
+                            bool DoNotFree = false);
 
   //===--------------------------------------------------------------------===//
   // FileID manipulation methods.
@@ -768,7 +794,7 @@ public:
   unsigned sloc_entry_size() const { return SLocEntryTable.size(); }
 
   // FIXME: Exposing this is a little gross; what we want is a good way
-  //  to iterate the entries that were not defined in a PCH file (or
+  //  to iterate the entries that were not defined in an AST file (or
   //  any other external source).
   unsigned sloc_loaded_entry_size() const { return SLocEntryLoaded.size(); }