[llvm] [AArch64] Combine truncate(buildvector) -> buildvector (PR #223787)

[Sjoerd Meijer via llvm-commits]

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@@ -23992,6 +23992,13 @@ static SDValue performTruncateCombine(SDNode *N, SelectionDAG &DAG,
     return DAG.getExtractVectorElt(DL, VT, Op, ExtractIndex * 2);
   }
 
+  // truncate(buildvector) -> buildvector if we still have it late in the
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sjoerdmeijer wrote:

Nit: maybe rephrase "if we still have it late"?

https://github.com/llvm/llvm-project/pull/223787