Switch lowering: fix APInt overflow causing infinite loop / OOM

[oota-llvm.git] / lib / CodeGen / SelectionDAG / SelectionDAGBuilder.cpp

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 14421834a553a186f131779bb88bc0b2c0dfd026..01419cf8fa1cbf7d88af17bd1dd329f5bb2543fa 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -7236,7 +7236,8 @@ bool SelectionDAGBuilder::buildJumpTable(CaseClusterVector &Clusters,
       for (uint64_t J = 0; J < Gap; J++)
         Table.push_back(DefaultMBB);
     }
-    for (APInt X = Low; X.sle(High); ++X)
+    uint64_t ClusterSize = (High - Low).getLimitedValue() + 1;
+    for (uint64_t J = 0; J < ClusterSize; ++J)
       Table.push_back(Clusters[I].MBB);
     JTWeights[Clusters[I].MBB] += Clusters[I].Weight;
   }