[llvm] [SelectionDAG] Fix incorrect expansion of `CONVERT_TO_ARBITRARY_FP` (PR #221358)

[Dmitry Sidorov via llvm-commits]

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@@ -9370,6 +9370,21 @@ SDValue TargetLowering::expandCONVERT_TO_ARBITRARY_FP(SDNode *Node,
   // expansion stays vector when ResVT is a vector.
   EVT IntScalarVT = EVT::getIntegerVT(*DAG.getContext(), SrcBits);
   EVT IntVT = ResVT.changeElementType(*DAG.getContext(), IntScalarVT);
+  if (!IntVT.isVector()) {
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MrSidims wrote:

nit: looks like this routine can be outlined in a helper as it's also used few lines below again.

https://github.com/llvm/llvm-project/pull/221358