[llvm] [LTO] Add an option to select a pre-link pipeline (PR #82585)

[Arthur Eubanks via llvm-commits]

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@@ -63,6 +63,9 @@ struct Config {
   /// Use the standard optimization pipeline.
   bool UseDefaultPipeline = false;
 
+  /// Use pre-link pipeline.
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aeubanks wrote:

`pre-link optimization pipeline`

https://github.com/llvm/llvm-project/pull/82585