[llvm] Nvptx port LowerBITCAST to SelectionDAG (PR #120903)

[Simon Pilgrim via llvm-commits]

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@@ -2619,7 +2595,7 @@ NVPTXTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   case ISD::BUILD_VECTOR:
     return LowerBUILD_VECTOR(Op, DAG);
   case ISD::BITCAST:
-    return LowerBITCAST(Op, DAG);
+    return SDValue();
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RKSimon wrote:

DAGTypeLegalizer::ExpandRes_BITCAST already does what you're after (expand bitcast of vector to scalar integer) in a more general form - maybe start there?

https://github.com/llvm/llvm-project/pull/120903