1 files changed, 22 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 98eb1a1bfe7..43a1005d84a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5279,6 +5279,23 @@ SDValue DAGCombiner::visitORLike(SDValue N0, SDValue N1, SDNode *N) {
   return SDValue();
 }
 
+/// OR combines for which the commuted variant will be tried as well.
+static SDValue visitORCommutative(
+    SelectionDAG &DAG, SDValue N0, SDValue N1, SDNode *N) {
+  EVT VT = N0.getValueType();
+  if (N0.getOpcode() == ISD::AND) {
+    // fold (or (and X, (xor Y, -1)), Y) -> (or X, Y)
+    if (isBitwiseNot(N0.getOperand(1)) && N0.getOperand(1).getOperand(0) == N1)
+      return DAG.getNode(ISD::OR, SDLoc(N), VT, N0.getOperand(0), N1);
+
+    // fold (or (and (xor Y, -1), X), Y) -> (or X, Y)
+    if (isBitwiseNot(N0.getOperand(0)) && N0.getOperand(0).getOperand(0) == N1)
+      return DAG.getNode(ISD::OR, SDLoc(N), VT, N0.getOperand(1), N1);
+  }
+
+  return SDValue();
+}
+
 SDValue DAGCombiner::visitOR(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
@@ -5426,6 +5443,11 @@ SDValue DAGCombiner::visitOR(SDNode *N) {
     }
   }
 
+  if (SDValue Combined = visitORCommutative(DAG, N0, N1, N))
+    return Combined;
+  if (SDValue Combined = visitORCommutative(DAG, N1, N0, N))
+    return Combined;
+
   // Simplify: (or (op x...), (op y...))  -> (op (or x, y))
   if (N0.getOpcode() == N1.getOpcode())
     if (SDValue V = hoistLogicOpWithSameOpcodeHands(N))