[llvm] [llvm-exegesis] Add option to specify the number of measurement repetitions (PR #74276)

[Aiden Grossman via llvm-commits]

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@@ -262,7 +262,8 @@ class ExegesisTarget {
       Benchmark::ModeE Mode, const LLVMState &State,
       BenchmarkPhaseSelectorE BenchmarkPhaseSelector,
       BenchmarkRunner::ExecutionModeE ExecutionMode,
-      Benchmark::ResultAggregationModeE ResultAggMode = Benchmark::Min) const;
+      Benchmark::ResultAggregationModeE ResultAggMode = Benchmark::Min,
+      unsigned BenchmarkRepeatCount = 30) const;
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boomanaiden154 wrote:

Shouldn't be needed. I've removed it.

Also caught that I never plumbed the flag into the call in `llvm-exegesis.cpp`, so I've also added that in this patch.

https://github.com/llvm/llvm-project/pull/74276