[llvm] [AMDGPU][SDAG] Legalise v2i32 or/xor/and instructions to make use of 64-bit wide instructions (PR #140694)

[Janek van Oirschot via llvm-commits]

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@@ -12916,13 +12985,39 @@ SDValue SITargetLowering::performXorCombine(SDNode *N,
   if (SDValue RV = reassociateScalarOps(N, DCI.DAG))
     return RV;
 
+  SelectionDAG &DAG = DCI.DAG;
+  EVT VT = N->getValueType(0);
   SDValue LHS = N->getOperand(0);
   SDValue RHS = N->getOperand(1);
 
+  if (VT == MVT::v2i32 && LHS.getNumOperands() > 1) {
+
+    const ConstantSDNode *CRHS_0 = dyn_cast<ConstantSDNode>(RHS.getOperand(0));
+    const ConstantSDNode *CRHS_1 = dyn_cast<ConstantSDNode>(RHS.getOperand(1));
+    SDValue LHS_0 = LHS.getOperand(0);
+    SDValue LHS_1 = LHS.getOperand(1);
+
+    if (LHS.getOpcode() == ISD::VSELECT && VT == MVT::v2i32) {
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JanekvO wrote:

VT already changed in previous `if`

https://github.com/llvm/llvm-project/pull/140694