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

[Matt Arsenault via llvm-commits]

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@@ -190,6 +188,28 @@ static DecodeStatus decodeImm1_16Operand(MCInst &Inst, uint64_t Imm,
   return MCDisassembler::Success;
 }
 
+static DecodeStatus decodeImm1n_15Operand(MCInst &Inst, uint64_t Imm,
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arsenm wrote:

Missing disassembler tests 

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