[llvm] [BOLT][DWARF][NFC] Add parallelization for processing of DWO debug information (PR #100282)

[Sayhaan Siddiqui via llvm-commits]

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@@ -50,7 +50,7 @@ enum SchedulingPolicy {
 };
 
 /// Return the managed thread pool and initialize it if not initialized.
-ThreadPoolInterface &getThreadPool();
+ThreadPoolInterface &getThreadPool(const int ThreadsCount = opts::ThreadCount);
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sayhaan wrote:

> I meant not for default, but at call site in DWARFRewriter.cpp

So for the default opt value, correct? Instead of cl::init(1).

https://github.com/llvm/llvm-project/pull/100282