1 files changed, 8 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 290e87a1f0f..f14f0463000 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -7272,6 +7272,14 @@ ScalarEvolution::ExitLimit ScalarEvolution::computeExitLimitFromCondImpl(
         if (EL0.ExactNotTaken == EL1.ExactNotTaken)
           BECount = EL0.ExactNotTaken;
       }
+      // There are cases (e.g. PR26207) where computeExitLimitFromCond is able
+      // to be more aggressive when computing BECount than when computing
+      // MaxBECount.  In these cases it is possible for EL0.ExactNotTaken and
+      // EL1.ExactNotTaken to match, but for EL0.MaxNotTaken and EL1.MaxNotTaken
+      // to not.
+      if (isa<SCEVCouldNotCompute>(MaxBECount) &&
+          !isa<SCEVCouldNotCompute>(BECount))
+        MaxBECount = getConstant(getUnsignedRangeMax(BECount));
 
       return ExitLimit(BECount, MaxBECount, false,
                        {&EL0.Predicates, &EL1.Predicates});