[llvm] [Xtensa] Implement lowering SELECT_CC, SETCC. (PR #97017)

[Andrei Safronov via llvm-commits]

================
@@ -514,6 +530,38 @@ XtensaTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
   return DAG.getNode(XtensaISD::RET, DL, MVT::Other, RetOps);
 }
 
+SDValue XtensaTargetLowering::LowerSELECT_CC(SDValue Op,
+                                             SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  EVT Ty = Op.getOperand(0).getValueType();
+  SDValue LHS = Op.getOperand(0);
+  SDValue RHS = Op.getOperand(1);
+  SDValue TrueValue = Op.getOperand(2);
+  SDValue FalseValue = Op.getOperand(3);
+  ISD::CondCode CC = cast<CondCodeSDNode>(Op->getOperand(4))->get();
+  SDValue TargetCC = DAG.getConstant(CC, DL, MVT::i32);
+
+  // Wrap select nodes
+  return DAG.getNode(XtensaISD::SELECT_CC, DL, Ty, LHS, RHS, TrueValue,
+                     FalseValue, TargetCC);
+}
+
+SDValue XtensaTargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  EVT Ty = Op.getOperand(0).getValueType();
+  SDValue LHS = Op.getOperand(0);
+  SDValue RHS = Op.getOperand(1);
+  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
+  SDValue TargetCC = DAG.getConstant(CC, DL, MVT::i32);
+
+  // Expand to target SELECT_CC
----------------
andreisfr wrote:

Yes, at current stage it produce the same result, so I removed custom setcc lowering, I will add specific version in next patches. Fixed

https://github.com/llvm/llvm-project/pull/97017