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Signed-off-by: Ryszard Rozak <rrozak@antmicro.com>

src/V3AstNodeOther.h

@@ -2956,7 +2956,8 @@ public:
 };
 class AstCoverInc final : public AstNodeStmt {
     // Coverage analysis point; increment coverage count
-    // @astgen op1 := toggleExprp : Optional[AstNodeExpr]
+    // @astgen op1 := toggleExprp : Optional[AstNodeExpr]  // [After V3Clock] Expression to which
+    // the node corresponds. Used only in toggle coverage
     //
     // @astgen ptr := m_declp : AstCoverDecl  // [After V3CoverageJoin] Declaration
 public:

src/V3EmitCFunc.h

@@ -640,6 +640,7 @@ public:
     void visit(AstCoverDecl* nodep) override {
         std::vector<string> pointSuffixes;
         if (nodep->isToggle()) {
+            // Changes 0 -> 1 and 1 -> 0 have separate counters
             pointSuffixes = {"_0", "_1"};
         } else {
             pointSuffixes = {""};