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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 a9a444f93a2b0d7a44abec96dc8539406e5530b4..b8bcdd41654f54054b267a3169b859ac9cdf96f2 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -4634,6 +4634,8 @@ ScalarEvolution::HowFarToNonZero(const SCEV *V, const Loop *L) {
 
 /// 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();