Make sure type is not extended or untyped before create a constant of the type. No test case. Found by inspection.

llvm-svn: 159179
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 0bdd8b8..28c3be9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5020,6 +5020,10 @@
   LoadSDNode *LN0 = cast<LoadSDNode>(N0);
   EVT PtrType = N0.getOperand(1).getValueType();
 
+  if (PtrType == MVT::Untyped || PtrType.isExtended())
+    // It's not possible to generate a constant of extended or untyped type.
+    return SDValue();
+
   // For big endian targets, we need to adjust the offset to the pointer to
   // load the correct bytes.
   if (TLI.isBigEndian()) {