dicrease the complexity of CalcDep from exponential to linear

apache · Oct 3, 2019 · f75253c · f75253c
1 parent 7d911f4
commit f75253c
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/src/relay/pass/dead_code.cc b/src/relay/pass/dead_code.cc
@@ -110,7 +110,11 @@ class CalcDep : private ExprVisitor {
   VarMap<size_t> use_map_;
 
   void VisitExpr(const Expr& e) final {
-    return ExprFunctor<void(const Expr& e)>::VisitExpr(e);
+    visit_counter_[e.get()]++;
+    if (visit_counter_[e.get()] <= 2) {
+      using TParent = ExprFunctor<void(const Expr&)>;
+      TParent::VisitExpr(e);
+    }
   }
 
   void VisitExpr_(const LetNode* l) final {