[llvm] [Coverage] Rework Decision/Expansion/Branch (PR #78969)

[NAKAMURA Takumi via llvm-commits]

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@@ -582,6 +583,87 @@ static unsigned getMaxBitmapSize(const CounterMappingContext &Ctx,
   return MaxBitmapID + (SizeInBits / CHAR_BIT);
 }
 
+/// This holds the DecisionRegion and MCDCBranch(es) under it.
+/// Also traverses Expansion(s).
+struct DecisionRow {
+  /// The subject
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chapuni wrote:

It came from "should-name-everything-syndrome". I think it'd be enough to mention from the class comment.

https://github.com/llvm/llvm-project/pull/78969