[llvm] [DAG] Remove OneUse restriction on sext when folding (shl (sext (add_nsw x, c1)), c2) (PR #68972)

[Simon Pilgrim via llvm-commits]

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@@ -3304,6 +3304,13 @@ X86TargetLowering::preferredShiftLegalizationStrategy(
                                                             ExpansionFactor);
 }
 
+bool X86TargetLowering::isDesirableToCommuteWithShift(
+    const SDNode *N, CombineLevel Level) const {
+  if (N->getOperand(0)->hasOneUse())
+    return true;
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RKSimon wrote:

This doesn't look like the hasOneUse is being applied to the same operand as the original?

https://github.com/llvm/llvm-project/pull/68972