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Author: teresajohnson

llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp

@@ -5579,6 +5579,12 @@ void MemProfContextDisambiguation::performICP(
                                  .getCallee());
         }
         DirectCall.setCalledFunction(TargetToUse);
+        // During matching we generate synthetic VP metadata for indirect calls
+        // not already having any, from the memprof profile's callee GUIDs. If
+        // we subsequently promote and inline those callees, we currently lose
+        // the ability to generate this synthetic VP metadata. Optionally apply
+        // a noinline attribute to promoted direct calls, where the threshold is
+        // set to capture synthetic VP metadata targets which get a count of 1.
         if (MemProfICPNoInlineThreshold &&
             Candidate.Count < MemProfICPNoInlineThreshold)
           DirectCall.setIsNoInline();