[llvm] [DAG] Fold freeze(shuffle(x,y,m)) -> shuffle(freeze(x),freeze(y),m) (PR #90952)

[Björn Pettersson via llvm-commits]

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@@ -15482,6 +15499,24 @@ SDValue DAGCombiner::visitFREEZE(SDNode *N) {
     }
   }
 
+  // Special case handling for ShuffleVectorSDNode nodes.
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bjope wrote:

Why isn't it enough to add VECTOR_SHUFFLE to AllowMultipleMaybePoisonOperands?

https://github.com/llvm/llvm-project/pull/90952