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

[Jessica Paquette via cfe-commits]

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@@ -676,41 +679,25 @@ struct MCDCCoverageBuilder {
     return E->getOpcode() == BO_LAnd;
   }
 
-  /// Push an ID onto the corresponding RHS stack.
-  void pushRHS(const BinaryOperator *E) {
-    llvm::SmallVector<MCDCConditionID> &rhs = isLAnd(E) ? AndRHS : OrRHS;
-    rhs.push_back(CondIDs[CodeGenFunction::stripCond(E->getRHS())]);
-  }
-
-  /// Pop an ID from the corresponding RHS stack.
-  void popRHS(const BinaryOperator *E) {
-    llvm::SmallVector<MCDCConditionID> &rhs = isLAnd(E) ? AndRHS : OrRHS;
-    if (!rhs.empty())
-      rhs.pop_back();
-  }
-
-  /// If the expected ID is on top, pop it off the corresponding RHS stack.
-  void popRHSifTop(const BinaryOperator *E) {
-    if (!OrRHS.empty() && CondIDs[E] == OrRHS.back())
-      OrRHS.pop_back();
-    else if (!AndRHS.empty() && CondIDs[E] == AndRHS.back())
-      AndRHS.pop_back();
-  }
-
 public:
   MCDCCoverageBuilder(CodeGenModule &CGM,
                       llvm::DenseMap<const Stmt *, MCDCConditionID> &CondIDMap,
                       llvm::DenseMap<const Stmt *, unsigned> &MCDCBitmapMap)
-      : CGM(CGM), CondIDs(CondIDMap), MCDCBitmapMap(MCDCBitmapMap) {}
+      : CGM(CGM), DecisionStack(1), CondIDs(CondIDMap),
+        MCDCBitmapMap(MCDCBitmapMap) {}
 
-  /// Return the ID of the RHS of the next, upper nest-level logical-OR.
-  MCDCConditionID getNextLOrCondID() const {
-    return OrRHS.empty() ? 0 : OrRHS.back();
-  }
+  /// Return whether the control flow map is not presently being built. This
+  /// can be used to determine whether the flow is at the root node of an
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ornata wrote:

I find the comment here kind of confusing.

I'd assume that `isIdle() == !isBuilding()` from this comment.

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