[clang] [llvm] [MC/DC] Refactor: Make `MCDCParams` as `std::variant` (PR #81227)

[NAKAMURA Takumi via llvm-commits]

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@@ -264,9 +266,10 @@ class MCDCRecordProcessor {
   MCDCRecordProcessor(const BitVector &Bitmap,
                       const CounterMappingRegion &Region,
                       ArrayRef<const CounterMappingRegion *> Branches)
-      : Bitmap(Bitmap), Region(Region), Branches(Branches),
-        NumConditions(Region.MCDCParams.NumConditions),
-        BitmapIdx(Region.MCDCParams.BitmapIdx * CHAR_BIT),
+      : Bitmap(Bitmap), Region(Region),
+        DecisionParams(Region.getDecisionParams()), Branches(Branches),
+        NumConditions(DecisionParams.NumConditions),
+        BitmapIdx(DecisionParams.BitmapIdx * CHAR_BIT),
         Folded(NumConditions, false), IndependencePairs(NumConditions),
         TestVectors((size_t)1 << NumConditions) {}
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chapuni wrote:

I'll make this mergeable later, possibly tonight.

https://github.com/llvm/llvm-project/pull/81227