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llvm-svn: 16400
diff --git a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
index 6e78ff8..7b5def4 100644
--- a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -82,7 +82,7 @@
 bool ArgPromotion::runOnSCC(const std::vector<CallGraphNode *> &SCC) {
   bool Changed = false, LocalChange;
 
-  do {
+  do {  // Iterate until we stop promoting from this SCC.
     LocalChange = false;
     // Attempt to promote arguments from all functions in this SCC.
     for (unsigned i = 0, e = SCC.size(); i != e; ++i)