[llvm] [DAGCombiner] Allow tryToFoldExtOfLoad to use a sextload for zext nneg. (PR #81714)

[Craig Topper via llvm-commits]

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@@ -13170,15 +13177,23 @@ static SDValue tryToFoldExtOfLoad(SelectionDAG &DAG, DAGCombiner &Combiner,
        !TLI.isLoadExtLegal(ExtLoadType, VT, N0.getValueType())))
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topperc wrote:

Good catch. Maybe I'll just pre-scan for signed setccs instead of trying to integrate it into the existing scan so I can do it early.

https://github.com/llvm/llvm-project/pull/81714