[llvm] [LLVM][TableGen] Change DAGISel code to use const RecordKeeper (PR #109038)

[Rahul Joshi via llvm-commits]

================
@@ -132,7 +132,8 @@ struct PatternSortingPredicate {
 } // End anonymous namespace
 
 void DAGISelEmitter::run(raw_ostream &OS) {
-  Records.startTimer("Parse patterns");
+  RecordKeeper &MutableRC = const_cast<RecordKeeper &>(Records);
----------------
jurahul wrote:

Ideally, I am thinking we should end up in a state like:

```
class TGContext {
    const RecordModule &getRecords() const;
    TGTimers &getTimers().
};
```

so we have a TGContext as the TG backend inputs and we rename `RecordKeeper` to `RecordModule`. I might take that up after this current refactor is done (of having better const correctness).

https://github.com/llvm/llvm-project/pull/109038