Detect undef value early and save unnecessary NodeMap query.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112864 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 08d2e93..e657445 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4074,6 +4074,17 @@
// absolute, but not relative, values are different depending on whether
// debug info exists.
++SDNodeOrder;
+
+ // Check if address has undef value.
+ if (isa<UndefValue>(Address) ||
+ (Address->use_empty() && !isa<Argument>(Address))) {
+ SDDbgValue*SDV =
+ DAG.getDbgValue(Variable, UndefValue::get(Address->getType()),
+ 0, dl, SDNodeOrder);
+ DAG.AddDbgValue(SDV, 0, false);
+ return 0;
+ }
+
SDValue &N = NodeMap[Address];
if (!N.getNode() && isa<Argument>(Address))
// Check unused arguments map.