[InstrProf]Merge vtable names from multiple sources in llvm-profdata

[minglotus-6]

This is essentially nfc but added for completeness, since llvm-profdata merge should merge profiles from the same instrumented binary, and the set of vtable names remains fixed for the same instrumented binary.

Otherwise, if value profiles from different instrumented binaries are used, the number of instrumented points for a particular function could be different; this could cause warnings at merge time or profile use time.

[github-actions]

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff 965f3ca3dc5464892e283e176bf058ae04d8b654 a67841bde64236e68fc8be0f30cba51204d2265e -- llvm/lib/ProfileData/InstrProfWriter.cpp

View the diff from clang-format here.

diff --git a/llvm/lib/ProfileData/InstrProfWriter.cpp b/llvm/lib/ProfileData/InstrProfWriter.cpp
index d842cdd278..5fe95d3b51 100644
--- a/llvm/lib/ProfileData/InstrProfWriter.cpp
+++ b/llvm/lib/ProfileData/InstrProfWriter.cpp
@@ -385,7 +385,7 @@ void InstrProfWriter::mergeRecordsFromWriter(InstrProfWriter &&IPW,
   for (auto &I : IPW.BinaryIds)
     addBinaryIds(I);
 
-  for (auto& kv: IPW.VTableNames)
+  for (auto &kv : IPW.VTableNames)
     addVTableName(kv.getKey());
 
   addTemporalProfileTraces(IPW.TemporalProfTraces,

[david-xl]

should we catch inconsistency here instead?