feat: add is_cyclic API to the CFG.

crates/oxc_semantic/src/control_flow/mod.rs

@@ -8,7 +8,7 @@ use oxc_syntax::operator::{
 };
 use petgraph::{
     stable_graph::NodeIndex,
-    visit::{Dfs, Walker},
+    visit::{depth_first_search, Dfs, DfsEvent, Walker},
     Graph,
 };
 
@@ -204,6 +204,14 @@ impl ControlFlowGraph {
             })
             .any(|x| x == to)
     }
+
+    pub fn is_cyclic(&self, node: BasicBlockId) -> bool {
+        depth_first_search(&self.graph, Some(node), |event| match event {
+            DfsEvent::BackEdge(_, id) if id == node => Err(()),
+            _ => Ok(()),
+        })
+        .is_err()
+    }
 }
 
 pub enum StatementControlFlowType {