[llvm] [TableGen] DecoderEmitter clean-ups and modernization. (PR #84832)

[Jason Eckhardt via llvm-commits]

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@@ -1760,14 +1759,14 @@ bool FilterChooser::filterProcessor(bool AllowMixed, bool Greedy) {
   bool AllUseless = true;
   unsigned BestScore = 0;
 
-  for (unsigned i = 0, e = Filters.size(); i != e; ++i) {
-    unsigned Usefulness = Filters[i].usefulness();
+  for (const auto &[I, TFilter] : enumerate(Filters)) {
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nvjle wrote:

Done. Also `TFilter` renamed to `Filter` (agreed, looks better than the previous which meant "temp" filter).

https://github.com/llvm/llvm-project/pull/84832