[clang] [llvm] [clang][CoverageMapping] Refactor when setting MC/DC True/False (PR #78202)

[NAKAMURA Takumi via cfe-commits]

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@@ -1884,20 +1874,28 @@ struct CounterCoverageMappingBuilder
   }
 
   void VisitBinLOr(const BinaryOperator *E) {
-    // Keep track of Binary Operator and assign MCDC condition IDs
+    bool IsRootNode = MCDCBuilder.isIdle();
+
+    // Keep track of Binary Operator and assign MCDC condition IDs.
     MCDCBuilder.pushAndAssignIDs(E);
 
     extendRegion(E->getLHS());
     Counter OutCount = propagateCounts(getRegion().getCounter(), E->getLHS());
     handleFileExit(getEnd(E->getLHS()));
 
+    // Track LHS True/False Decision.
+    auto DecisionLHS = MCDCBuilder.pop();
+
     // Counter tracks the right hand side of a logical or operator.
     extendRegion(E->getRHS());
     propagateCounts(getRegionCounter(E), E->getRHS());
 
-    // Process Binary Operator and create MCDC Decision Region if top-level
+    // Track RHS True/False Decision.
+    const auto DecisionRHS = MCDCBuilder.back();
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chapuni wrote:

You may drop `const`, or add `const` onto `DecisionLHS`. I know this is a nitpick.

https://github.com/llvm/llvm-project/pull/78202