From: Nirav Dave <niravd@google.com>
Date: Thu, 7 Feb 2019 16:57:50 +0000 (+0000)
Subject: [DAG] Cleanup unused node on failed SELECT Combine.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9aa1395994dcc8a7ea07e5144527761447fb681e;p=llvm

[DAG] Cleanup unused node on failed SELECT Combine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353426 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 9ef4f508ef1..b6023d52d6e 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -7444,6 +7444,9 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
       if (normalizeToSequence || !InnerSelect.use_empty())
         return DAG.getNode(ISD::SELECT, DL, N1.getValueType(), Cond0,
                            InnerSelect, N2);
+      // Cleanup on failure.
+      if (InnerSelect.use_empty())
+        recursivelyDeleteUnusedNodes(InnerSelect.getNode());
     }
     // select (or Cond0, Cond1), X, Y -> select Cond0, X, (select Cond1, X, Y)
     if (N0->getOpcode() == ISD::OR && N0->hasOneUse()) {
@@ -7454,6 +7457,9 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
       if (normalizeToSequence || !InnerSelect.use_empty())
         return DAG.getNode(ISD::SELECT, DL, N1.getValueType(), Cond0, N1,
                            InnerSelect);
+      // Cleanup on failure.
+      if (InnerSelect.use_empty())
+        recursivelyDeleteUnusedNodes(InnerSelect.getNode());
     }
 
     // select Cond0, (select Cond1, X, Y), Y -> select (and Cond0, Cond1), X, Y