this massive patch introduces a simple new abstraction: it makes

"FileID" a concept that is now enforced by the compiler's type checker
instead of yet-another-random-unsigned floating around.

This is an important distinction from the "FileID" currently tracked by
SourceLocation.  *That* FileID may refer to the start of a file or to a
chunk within it.  The new FileID *only* refers to the file (and its 
#include stack and eventually #line data), it cannot refer to a chunk.

FileID is a completely opaque datatype to all clients, only SourceManager
is allowed to poke and prod it.

llvm-svn: 62407

1 files changed, 3 insertions, 3 deletions

diff --git a/clang/lib/Lex/ScratchBuffer.cpp b/clang/lib/Lex/ScratchBuffer.cpp
index 99fbdf75654..ec07a71baf6 100644
--- a/clang/lib/Lex/ScratchBuffer.cpp
+++ b/clang/lib/Lex/ScratchBuffer.cpp
@@ -24,7 +24,6 @@ static const unsigned ScratchBufSize = 4060;
 ScratchBuffer::ScratchBuffer(SourceManager &SM) : SourceMgr(SM), CurBuffer(0) {
   // Set BytesUsed so that the first call to getToken will require an alloc.
   BytesUsed = ScratchBufSize;
-  FileID = 0;
 }
 
 /// getToken - Splat the specified text into a temporary MemoryBuffer and
@@ -44,7 +43,7 @@ SourceLocation ScratchBuffer::getToken(const char *Buf, unsigned Len) {
   assert(BytesUsed-Len < (1 << SourceLocation::FilePosBits) &&
          "Out of range file position!");
   
-  return SourceLocation::getFileLoc(FileID, BytesUsed-Len);
+  return BufferStartLoc.getFileLocWithOffset(BytesUsed-Len);
 }
 
 
@@ -66,7 +65,8 @@ void ScratchBuffer::AllocScratchBuffer(unsigned RequestLen) {
   
   llvm::MemoryBuffer *Buf = 
     llvm::MemoryBuffer::getNewMemBuffer(RequestLen, "<scratch space>");
-  FileID = SourceMgr.createFileIDForMemBuffer(Buf);
+  FileID FID = SourceMgr.createFileIDForMemBuffer(Buf);
+  BufferStartLoc = SourceMgr.getLocForStartOfFile(FID);
   CurBuffer = const_cast<char*>(Buf->getBufferStart());
   BytesUsed = 0;
 }