1 files changed, 4 insertions, 0 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 30d6e7088c..c53ec8a5f1 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -3328,6 +3328,10 @@ ScalarEvolution::getPredecessorWithUniqueSuccessorForBB(BasicBlock *BB) {
 bool ScalarEvolution::isLoopGuardedByCond(const Loop *L,
                                           ICmpInst::Predicate Pred,
                                           const SCEV *LHS, const SCEV *RHS) {
+  // Interpret a null as meaning no loop, where there is obviously no guard
+  // (interprocedural conditions notwithstanding).
+  if (!L) return false;
+
   BasicBlock *Predecessor = getLoopPredecessor(L);
   BasicBlock *PredecessorDest = L->getHeader();