[llvm] [TableGen] Add support for DefaultMode in per-HwMode encode/decode. (PR #83029)

[Craig Topper via llvm-commits]

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@@ -52,6 +52,11 @@ struct CodeGenHwModes {
     assert(Id != 0 && "Mode id of 0 is reserved for the default mode");
     return Modes[Id - 1];
   }
+  const StringRef getModeName(unsigned Id, bool IncludeDefault = false) const {
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topperc wrote:

Drop `const`. It doesn't do anything since it's returning by value.

https://github.com/llvm/llvm-project/pull/83029