[llvm] [OpenMP] Add optimization to remove the RPC client (PR #70683)

[Joseph Huber via llvm-commits]

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@@ -1507,6 +1510,40 @@ struct OpenMPOpt {
     return Changed;
   }
 
+  /// Tries to remove known runtime symbols that are optional.
+  bool removeRuntimeSymbols() {
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jhuber6 wrote:

I was thinking we might want something for another global in the future. I updated the comment to make it clearer that  'remove' is referring to the symbol table.

https://github.com/llvm/llvm-project/pull/70683