[llvm] [WIP][DAG] Add legalization handling for AVGCEIL/AVGFLOOR nodes (PR #92096)

[Jay Foad via llvm-commits]

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@@ -5332,6 +5332,11 @@ class TargetLowering : public TargetLoweringBase {
   /// \returns The expansion result or SDValue() if it fails.
   SDValue expandABD(SDNode *N, SelectionDAG &DAG) const;
 
+  /// Expand vector/scalar AVGCEILS/AVGCEILU/AVGFLOOR/AVGFLOORU nodes.
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jayfoad wrote:

```suggestion
  /// Expand vector/scalar AVGCEILS/AVGCEILU/AVGFLOORS/AVGFLOORU nodes.
```

https://github.com/llvm/llvm-project/pull/92096