diff --git a/compiler/optimizing/graph_visualizer.cc b/compiler/optimizing/graph_visualizer.cc
index cabfa48..49c0d38 100644
--- a/compiler/optimizing/graph_visualizer.cc
+++ b/compiler/optimizing/graph_visualizer.cc
@@ -149,6 +149,8 @@
       codegen_.DumpCoreRegister(output_, location.low());
       output_ << " and ";
       codegen_.DumpCoreRegister(output_, location.high());
+    } else if (location.IsUnallocated()) {
+      output_ << "<U>";
     } else {
       DCHECK(location.IsDoubleStackSlot());
       output_ << "2x" << location.GetStackIndex() << "(sp)";