[llvm] [llvm-profgen][SPGO] Support profiles with multiple concurrent processes (PR #169353)

[via llvm-commits]

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@@ -60,6 +60,13 @@ static cl::opt<int> CSProfMaxUnsymbolizedCtxDepth(
              "means no depth limit."),
     cl::cat(ProfGenCategory));
 
+static cl::opt<bool> MultiProcessProfile(
+    "multi-process-profile",
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Heath123 wrote:

See above: this is opt-in for compatibility. We can't use the PID filter argument for this, since it is optional and all PIDs are accepted if it is not passed.

https://github.com/llvm/llvm-project/pull/169353