[llvm] [llvm-exegesis] Add support for pinning benchmarking process to a CPU (PR #85168)

[Clement Courbet via llvm-commits]

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@@ -175,6 +179,7 @@ class InProcessFunctionExecutorImpl : public BenchmarkRunner::FunctionExecutor {
   const LLVMState &State;
   const ExecutableFunction Function;
   BenchmarkRunner::ScratchSpace *const Scratch;
+  const std::optional<int> BenchmarkProcessCPU;
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legrosbuffle wrote:

Why do we have this member ? It's never read and the feature is not supported in this mode.

https://github.com/llvm/llvm-project/pull/85168