Make sure to expand all nodes, avoiding unintentional node duplication.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21889 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index b8c4315..5cc148a 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -2168,6 +2168,13 @@
 
   TargetLowering::ArgListTy Args;
   const Type *ArgTy = MVT::getTypeForValueType(Source.getValueType());
+
+  // Expand the source, then glue it back together for the call.  We must expand
+  // the source in case it is shared (this pass of legalize must traverse it).
+  SDOperand SrcLo, SrcHi;
+  ExpandOp(Source, SrcLo, SrcHi);
+  Source = DAG.getNode(ISD::BUILD_PAIR, Source.getValueType(), SrcLo, SrcHi);
+
   Args.push_back(std::make_pair(Source, ArgTy));
 
   // We don't care about token chains for libcalls.  We just use the entry