[llvm] [Instrumentation] Fix EdgeCounts vector size in SetBranchWeights (PR #99064)

[Ellis Hoag via llvm-commits]

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@@ -1624,7 +1624,9 @@ void PGOUseFunc::setBranchWeights() {
 
     // We have a non-zero Branch BB.
     unsigned Size = BBCountInfo.OutEdges.size();
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ellishg wrote:

Could you also rename `Size` so it is more clear how it is different from `SuccessorCount`?

https://github.com/llvm/llvm-project/pull/99064