Add a missing check, which broke a bunch of vector tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27374 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5742aef..aacee99 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2756,9 +2756,12 @@
               Ops.back().getOpcode() == ISD::ConstantFP) &&
              "Scalar binop didn't fold!");
     }
-    Ops.push_back(*(LHS.Val->op_end()-2));
-    Ops.push_back(*(LHS.Val->op_end()-1));
-    return DAG.getNode(ISD::VBUILD_VECTOR, MVT::Vector, Ops);
+    
+    if (Ops.size() == LHS.getNumOperands()-2) {
+      Ops.push_back(*(LHS.Val->op_end()-2));
+      Ops.push_back(*(LHS.Val->op_end()-1));
+      return DAG.getNode(ISD::VBUILD_VECTOR, MVT::Vector, Ops);
+    }
   }
   
   return SDOperand();