add a new SourceManager::getInstantiationRange helper method.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64606 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 33b5ef8..a8b09e5 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -471,9 +471,7 @@
     // can matter for a function-like macro that expands to contain __LINE__.
     // Skip down through instantiation points until we find a file loc for the
     // end of the instantiation history.
-    while (!Loc.isFileID())
-      Loc = SourceMgr.getImmediateInstantiationRange(Loc).second;
-    
+    Loc = SourceMgr.getInstantiationRange(Loc).second;
     PresumedLoc PLoc = SourceMgr.getPresumedLoc(Loc);
     
     // __LINE__ expands to a simple numeric value.  Add a space after it so that