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

[Sergei Barannikov via llvm-commits]

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@@ -33,7 +33,14 @@ enum {
   // Wraps a TargetGlobalAddress that should be loaded using PC-relative
   // accesses.  Operand 0 is the address.
   PCREL_WRAPPER,
-  RET
+  RET,
+
+  // Selects between operand 0 and operand 1.  Operand 2 is the
+  // mask of condition-code values for which operand 0 should be
+  // chosen over operand 1; it has the same form as BR_CCMASK.
+  // Operand 3 is the flag operand.
+  SELECT,
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s-barannikov wrote:

SELECT is unused

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