[llvm] [Xtensa] Implement Code Density Option. (PR #119639)

[Andrei Safronov via llvm-commits]

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@@ -193,6 +193,10 @@ struct XtensaOperand : public MCParsedAsmOperand {
 
   bool isImm1_16() const { return isImm(1, 16); }
 
+  bool isImm1n_15() const { return (isImm(1, 15) || isImm(-1, -1)); }
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andreisfr wrote:

Thank you for review. I removed parens and added a comment.

https://github.com/llvm/llvm-project/pull/119639