[llvm] [Backend] Add clearSubtargetMap API for TargetMachine. (PR #112383)

[weiwei chen via llvm-commits]

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@@ -448,6 +448,9 @@ class LLVMTargetMachine : public TargetMachine {
 
   void initAsmInfo();
 
+  /// Reset internal state.
+  virtual void reset() {};
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weiweichen wrote:

This is a good point! Trying to balance all the review comments I got and I think I'll remove the implementation from the backend that I don't particularly care about and leave them with the default implementation here as a no-op and can always overload with specific implementations should the need arises in the future.

https://github.com/llvm/llvm-project/pull/112383