From 2dbc167294c1a7a4cd7a43f86bff104afd6110e5 Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Mon, 21 Jul 2008 21:04:07 +0000
Subject: [PATCH] After early-lowering the FORMAL_ARGUMENTS node, delete it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53874 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index b500b6ab6b3..12c54c1eeff 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -4686,6 +4686,13 @@ void TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG,
           (Result->getNumValues()+1 == TmpRes.Val->getNumValues() &&
            TmpRes.getValue(Result->getNumValues()).getValueType() == MVT::Flag))
          && "Lowering produced unexpected number of results!");
+
+  // The FORMAL_ARGUMENTS node itself is likely no longer needed.
+  if (Result != TmpRes.Val && Result->use_empty()) {
+    HandleSDNode Dummy(DAG.getRoot());
+    DAG.RemoveDeadNode(Result);
+  }
+
   Result = TmpRes.Val;
   
   unsigned NumArgRegs = Result->getNumValues() - 1;