[llvm] [llvm-exegesis] Add middle half repetition mode (PR #77020)

[Clement Courbet via llvm-commits]

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@@ -455,6 +466,26 @@ static void runBenchmarkConfigurations(
               Measurement.PerSnippetValue, NewMeasurement.PerSnippetValue);
         }
       }
+    } else if (RepetitionMode ==
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legrosbuffle wrote:

`AggregateResults` and the two agrgegator implementations could be moved to a separate file with unit tests :)

https://github.com/llvm/llvm-project/pull/77020