[llvm] [llvm-profgen] Infer callsite samples for functions without samples (PR #191572)

[via llvm-commits]

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@@ -1373,6 +1382,102 @@ void CSProfileGenerator::populateBoundarySamplesWithProbes(
   }
 }
 
+void CSProfileGenerator::inferCallsiteSamples() {
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WenleiHe wrote:

Why not do all of this as part of `populateBoundarySamplesWithProbesForAllFunctions`? 

https://github.com/llvm/llvm-project/pull/191572