jayzhan211 commented on code in PR #10386:
URL: https://github.com/apache/datafusion/pull/10386#discussion_r1592109596


##########
datafusion/optimizer/src/simplify_expressions/expr_simplifier.rs:
##########
@@ -1670,17 +1734,106 @@ fn inlist_except(mut l1: InList, l2: InList) -> 
Result<Expr> {
     Ok(Expr::InList(l1))
 }
 
+pub struct RewriteCycle {
+    consecutive_unchanged_count: usize,
+    total_iterations: usize,
+    num_rewriters: usize,
+}
+pub type RewriteCycleResult = ControlFlow<Result<Expr>, Expr>;
+
+impl RewriteCycle {
+    fn new() -> Self {
+        RewriteCycle {
+            // use usize::MAX as default to avoid checking null in is_done() 
comparison
+            // real value is set later by record_num_rewriters
+            num_rewriters: usize::MAX,
+            consecutive_unchanged_count: 0,
+            total_iterations: 0,
+        }
+    }
+
+    pub fn completed_cycles(&self) -> usize {
+        // default value indicates we have not completed a cycle
+        if self.num_rewriters == usize::MAX {
+            0
+        } else {
+            self.total_iterations / self.num_rewriters
+        }
+    }
+
+    pub fn total_iterations(&self) -> usize {
+        self.total_iterations
+    }
+
+    fn record_num_rewriters(&mut self) {
+        self.num_rewriters = self.total_iterations;
+    }
+
+    fn is_done(&self) -> bool {
+        self.consecutive_unchanged_count >= self.num_rewriters

Review Comment:
   > so in this case for example if the const evaluator returns false, simpliy 
could still return true
   
   In this case, transformed is true, so we should run another pass. 
   I think once we found every rules is not transformed, we can stop the passes 



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