X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FAnalysis%2FScalarEvolution.cpp;h=ef1bb3a36c8d4205652560cfa9c04bf112c9e540;hp=34074efd1cebcce7fe41395dd8d3e98c4bed374f;hb=44fb5881d8edf448d6231a5b8df583aecd6bcd42;hpb=4d1ef71f362e014aaaaefeb36abe83c24b578e40

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 34074efd1ce..ef1bb3a36c8 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -5368,6 +5368,14 @@ ScalarEvolution::computeExitLimitFromCond(const Loop *L,
           BECount = EL0.Exact;
       }
 
+      // 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.Exact and EL1.Exact
+      // to match, but for EL0.Max and EL1.Max to not.
+      if (isa<SCEVCouldNotCompute>(MaxBECount) &&
+          !isa<SCEVCouldNotCompute>(BECount))
+        MaxBECount = BECount;
+
       return ExitLimit(BECount, MaxBECount);
     }
     if (BO->getOpcode() == Instruction::Or) {