[llvm] [TableGen][DecoderEmitter] Add option to emit type-specialized `decodeToMCInst` (PR #146593)

[Rahul Joshi via llvm-commits]

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@@ -216,6 +217,20 @@ struct EncodingIDAndOpcode {
 using EncodingIDsVec = std::vector<EncodingIDAndOpcode>;
 using NamespacesHwModesMap = std::map<std::string, std::set<StringRef>>;
 
+// A struct to represent the C++ type for the instruction payload.
+struct CPPType {
+  enum TypeKind { TemplateTy, UIntTy, APIntTy, BitsetTy } Kind;
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jurahul wrote:

I am not sure. Custom doesn't convey the intent (i.e., it could a custom concrete type) and won't match with the option name `GenerateTemplatedDecoder` and use of the template terminology throughout the code (GenerateTemplated, emitTemplate etc).

https://github.com/llvm/llvm-project/pull/146593