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

[Simon Pilgrim via llvm-commits]

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@@ -910,6 +910,96 @@ SDValue DAGTypeLegalizer::CreateStackStoreLoad(SDValue Op,
   return DAG.getLoad(DestVT, dl, Store, StackPtr, MachinePointerInfo(), Align);
 }
 
+SDValue DAGTypeLegalizer::PackBitcastInRegister(SDNode *N) const {
+  assert(N->getOpcode() == ISD::BITCAST && "Unexpected opcode!");
+
+  EVT FromVT = N->getOperand(0)->getValueType(0);
+  EVT ToVT = N->getValueType(0);
+
+  if (!FromVT.isVector() || !ToVT.isInteger())
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RKSimon wrote:

ToVT.isScalarInteger() - otherwise it'll match integer vectors as well

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