1 files changed, 15 insertions, 3 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index bfb0c0dfb60..163e1fe62d6 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -6606,7 +6606,7 @@ const SCEV *ScalarEvolution::getExitCount(const Loop *L,
   case Exact: 
     return getBackedgeTakenInfo(L).getExact(ExitingBlock, this);
   case ConstantMaximum:
-    return getCouldNotCompute();
+    return getBackedgeTakenInfo(L).getMax(ExitingBlock, this);
   };
   llvm_unreachable("Invalid ExitCountKind!");
 }
@@ -6934,6 +6934,16 @@ ScalarEvolution::BackedgeTakenInfo::getExact(BasicBlock *ExitingBlock,
   return SE->getCouldNotCompute();
 }
 
+const SCEV *
+ScalarEvolution::BackedgeTakenInfo::getMax(BasicBlock *ExitingBlock,
+                                           ScalarEvolution *SE) const {
+  for (auto &ENT : ExitNotTaken)
+    if (ENT.ExitingBlock == ExitingBlock && ENT.hasAlwaysTruePredicate())
+      return ENT.MaxNotTaken;
+
+  return SE->getCouldNotCompute();
+}
+
 /// getMax - Get the max backedge taken count for the loop.
 const SCEV *
 ScalarEvolution::BackedgeTakenInfo::getMax(ScalarEvolution *SE) const {
@@ -7025,13 +7035,15 @@ ScalarEvolution::BackedgeTakenInfo::BackedgeTakenInfo(
         BasicBlock *ExitBB = EEI.first;
         const ExitLimit &EL = EEI.second;
         if (EL.Predicates.empty())
-          return ExitNotTakenInfo(ExitBB, EL.ExactNotTaken, nullptr);
+          return ExitNotTakenInfo(ExitBB, EL.ExactNotTaken, EL.MaxNotTaken,
+                                  nullptr);
 
         std::unique_ptr<SCEVUnionPredicate> Predicate(new SCEVUnionPredicate);
         for (auto *Pred : EL.Predicates)
           Predicate->add(Pred);
 
-        return ExitNotTakenInfo(ExitBB, EL.ExactNotTaken, std::move(Predicate));
+        return ExitNotTakenInfo(ExitBB, EL.ExactNotTaken, EL.MaxNotTaken,
+                                std::move(Predicate));
       });
   assert((isa<SCEVCouldNotCompute>(MaxCount) || isa<SCEVConstant>(MaxCount)) &&
          "No point in having a non-constant max backedge taken count!");