[llvm] [SelectionDAG] Salvage debuginfo when combining load and z|s ext instrs. (PR #188544)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -14795,6 +14801,9 @@ static SDValue tryToFoldExtOfLoad(SelectionDAG &DAG, DAGCombiner &Combiner,
                                   ISD::LoadExtType ExtLoadType,
                                   ISD::NodeType ExtOpc,
                                   bool NonNegZExt = false) {
+  unsigned Opcode_N = N->getOpcode();
+  bool IsSigned = Opcode_N == ISD::SIGN_EXTEND;
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OCHyams wrote:

nit: Can we sink this bit of code closer to its uses?

https://github.com/llvm/llvm-project/pull/188544