[llvm] [SelectionDAG] Propogate Disjoint flag. (PR #88370)

[Matt Arsenault via llvm-commits]

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@@ -9530,6 +9530,8 @@ static SDValue combineShiftOfShiftedLogic(SDNode *Shift, SelectionDAG &DAG) {
   SDValue ShiftSumC = DAG.getConstant(*C0Val + C1Val, DL, ShiftAmtVT);
   SDValue NewShift1 = DAG.getNode(ShiftOpcode, DL, VT, X, ShiftSumC);
   SDValue NewShift2 = DAG.getNode(ShiftOpcode, DL, VT, Y, C1);
+  // Propogate flags.
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arsenm wrote:

Drop comment 

https://github.com/llvm/llvm-project/pull/88370