[llvm] [Xtensa] Implement Windowed Register Option. (PR #124656)

[Fangrui Song via llvm-commits]

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@@ -73,17 +73,23 @@ static DecodeStatus DecodeARRegisterClass(MCInst &Inst, uint64_t RegNo,
   return MCDisassembler::Success;
 }
 
-static const unsigned SRDecoderTable[] = {Xtensa::SAR, 3};
+static const unsigned SRDecoderTable[] = {
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MaskRay wrote:

can omit `static` since const at a namespace scope by default has the internal linkage

https://github.com/llvm/llvm-project/pull/124656