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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101248 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index a9a444f..b8bcdd4 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -4634,6 +4634,8 @@
/// getLoopPredecessor - If the given loop's header has exactly one unique
/// predecessor outside the loop, return it. Otherwise return null.
+/// This is less strict that the loop "preheader" concept, which requires
+/// the predecessor to have only one single successor.
///
BasicBlock *ScalarEvolution::getLoopPredecessor(const Loop *L) {
BasicBlock *Header = L->getHeader();