Handle loop vs. simple induced clones better

hercules_ir/src/subgraph.rs

@@ -23,6 +23,7 @@ pub struct Subgraph {
     original_num_nodes: u32,
 }
 
+#[derive(Debug, Clone)]
 pub struct SubgraphIterator<'a> {
     nodes: &'a Vec<NodeID>,
     edges: &'a [u32],

juno_samples/implicit_clone/src/implicit_clone.jn

@@ -64,16 +64,32 @@ fn tricky_loop_implicit_clone(a : usize, b : usize) -> i32 {
 fn tricky2_loop_implicit_clone(a : usize, b : usize) -> i32 {
   let x = 0;
   for i = 0 to 3 {
-    let arr : i32[1];
+    let arr1 : i32[1];
+    let arr2 : i32[1];
     if a == b {
-      arr[0] = 6;
+      arr1[0] = 6;
     } else {
-      arr[0] = 9;
+      arr2[0] = 9;
     }
+    arr1[0] = 2;
     for j = 0 to 4 {
-      arr[0] += 1;
+      arr2[0] += 1;
+    }
+    x += arr2[0];
+  }
+  return x;
+}
+
+#[entry]
+fn tricky3_loop_implicit_clone(a : usize, b : usize) -> usize {
+  let x = 0;
+  for i = 0 to b {
+    let arr1 : usize[10];
+    let arr2 : usize[10];
+    arr1[1] = 1;
+    for kk = 0 to 10 {
+      arr2[kk] += arr1[kk];
     }
-    x += arr[0];
   }
   return x;
 }

juno_samples/implicit_clone/src/main.rs

@@ -27,6 +27,10 @@ fn main() {
         println!("{}", output);
         assert_eq!(output, 39);
 
+        let output = tricky3_loop_implicit_clone(5, 7).await;
+        println!("{}", output);
+        assert_eq!(output, 0);
+
         let output = no_implicit_clone(4).await;
         println!("{}", output);
         assert_eq!(output, 13);