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

[Andrei Safronov via llvm-commits]

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@@ -90,6 +90,26 @@ XtensaTargetLowering::XtensaTargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::BR_CC, MVT::i64, Expand);
   setOperationAction(ISD::BR_CC, MVT::f32, Expand);
 
+  // Used by legalize types to correctly generate the setcc result.
+  // AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
+  setOperationPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
+  setOperationPromotedToType(ISD::BR_CC, MVT::i1, MVT::i32);
+
+  setOperationAction(ISD::BR_CC, MVT::i32, Legal);
+  setOperationAction(ISD::BR_CC, MVT::i64, Expand);
+
+  setOperationAction(ISD::SELECT, MVT::i32, Expand);
+  setOperationAction(ISD::SELECT, MVT::i64, Expand);
+
+  setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
+  setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
+
+  setOperationAction(ISD::SETCC, MVT::i32, Custom);
+  setOperationAction(ISD::SETCC, MVT::i64, Expand);
+
+  // make BRCOND legal, its actually only legal for a subset of conds
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andreisfr wrote:

I removed code related to BRCOND from this PR, seems it is redundant , I will add it in next patches.

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