diff --git a/examples/gemm/gemm_codegen.rs b/examples/gemm/gemm_codegen.rs
index 8aa3c76..fd82123 100644
--- a/examples/gemm/gemm_codegen.rs
+++ b/examples/gemm/gemm_codegen.rs
@@ -25,7 +25,7 @@ fn main() {
 
     global_graph.add_nodes(vec![shared_block_node.clone()]);
 
-    let global_graph = Rc::new(global_graph);
+    let global_graph = Rc::new(RefCell::new(global_graph));
 
     let global_block = ThrillerBlock::new(
         vec![],
diff --git a/examples/gemm/global_block.rs b/examples/gemm/global_block.rs
index 6b1fd09..20296ac 100644
--- a/examples/gemm/global_block.rs
+++ b/examples/gemm/global_block.rs
@@ -25,7 +25,7 @@ fn main() {
 
     global_graph.add_nodes(vec![shared_block_node.clone()]);
 
-    let global_graph = Rc::new(global_graph);
+    let global_graph = Rc::new(RefCell::new(global_graph));
 
     let global_block = ThrillerBlock::new(
         vec![],
diff --git a/examples/gemm/rf_block.rs b/examples/gemm/rf_block.rs
index dd849c0..65a8d33 100644
--- a/examples/gemm/rf_block.rs
+++ b/examples/gemm/rf_block.rs
@@ -89,7 +89,7 @@ fn main() {
         vec![Rc::new(in_edge0), Rc::new(in_edge1)],
         vec![Rc::new(out_edge)],
         MemoryLevel::Register,
-        Rc::new(subgraph),
+        Rc::new(RefCell::new(subgraph)),
         BlockType::Reduce,
     );
 
diff --git a/examples/gemm/shared_block.rs b/examples/gemm/shared_block.rs
index ab69099..42f409c 100644
--- a/examples/gemm/shared_block.rs
+++ b/examples/gemm/shared_block.rs
@@ -87,7 +87,7 @@ fn main() {
         vec![Rc::new(in_edge0), Rc::new(in_edge1)],
         vec![Rc::new(out_edge)],
         MemoryLevel::Shared,
-        Rc::new(subgraph),
+        Rc::new(RefCell::new(subgraph)),
         BlockType::Map,
     );
 
diff --git a/examples/loop/multiloops.rs b/examples/loop/multiloops.rs
index 0090899..30a0a4e 100644
--- a/examples/loop/multiloops.rs
+++ b/examples/loop/multiloops.rs
@@ -1,4 +1,4 @@
-use std::rc::Rc;
+use std::{cell::RefCell, rc::Rc};
 
 use thriller_core::{
     initialize, AccessMap, AccessMatrix, AccessOffset, AttachedEdge, BlockType, IterationBound,
@@ -57,7 +57,7 @@ fn main() {
         vec![Rc::new(in_edge0), Rc::new(in_edge1), Rc::new(in_edge2)],
         vec![],
         MemoryLevel::Register,
-        Rc::new(subgraph),
+        Rc::new(RefCell::new(subgraph)),
         BlockType::Reduce,
     );
 
diff --git a/thriller-core/src/dataflow/block.rs b/thriller-core/src/dataflow/block.rs
index 45238ee..52dc673 100644
--- a/thriller-core/src/dataflow/block.rs
+++ b/thriller-core/src/dataflow/block.rs
@@ -1,3 +1,4 @@
+use std::cell::RefCell;
 use std::rc::Rc;
 use std::vec::Vec;
 
@@ -26,7 +27,7 @@ pub struct ThrillerBlock {
     pub(crate) inputs: Vec<Rc<AttachedEdge>>,
     pub(crate) outputs: Vec<Rc<AttachedEdge>>,
     pub(crate) mem_level: MemoryLevel,
-    pub(crate) subgraph: Rc<ThrillerGraph>,
+    pub(crate) subgraph: Rc<RefCell<ThrillerGraph>>,
     pub(crate) block_type: BlockType,
     pub(crate) unified_access_map: Option<Rc<AccessMap>>,
     pub(crate) loop_groups: Vec<LoopGroup>,
@@ -38,7 +39,7 @@ impl ThrillerBlock {
         inputs: Vec<Rc<AttachedEdge>>,
         outputs: Vec<Rc<AttachedEdge>>,
         mem_level: MemoryLevel,
-        subgraph: Rc<ThrillerGraph>,
+        subgraph: Rc<RefCell<ThrillerGraph>>,
         block_type: BlockType,
     ) -> Self {
         ThrillerBlock {
@@ -228,11 +229,11 @@ impl ThrillerBlock {
             if self.mem_level == MemoryLevel::Shared {
                 inner_code += Sync::emit_copy_async().as_str();
             }
-            inner_code += self.subgraph.emit()?.as_str();
+            inner_code += self.subgraph.borrow().emit()?.as_str();
             code += access_map.gen_loop_access(inner_code)?.as_str();
 
             code += Sync::emit_sync().as_str();
-            if let Some(reduce_outputs) = self.subgraph.reduce_block_outputs() {
+            if let Some(reduce_outputs) = self.subgraph.borrow().reduce_block_outputs() {
                 // self.outputs.extend(reduce_outputs);
                 for output in reduce_outputs {
                     code += &self.emit_store(&output)?;
@@ -244,7 +245,7 @@ impl ThrillerBlock {
         } else {
             // TODO: Handle cases without an unified access map.
             if self.inputs.is_empty() && self.outputs.is_empty() {
-                let code = self.subgraph.emit()?;
+                let code = self.subgraph.borrow().emit()?;
                 Ok(code)
             } else {
                 // unimplemented!();
diff --git a/thriller-core/src/dataflow/node.rs b/thriller-core/src/dataflow/node.rs
index f116283..58aafa9 100644
--- a/thriller-core/src/dataflow/node.rs
+++ b/thriller-core/src/dataflow/node.rs
@@ -68,8 +68,8 @@ impl ThrillerNode {
         &self.nexts
     }
 
-    #[allow(dead_code)]
-    pub(crate) fn get_inner(&self) -> &ThrillerNodeInner {
+    #[doc(hidden)]
+    pub fn get_inner(&self) -> &ThrillerNodeInner {
         &self.inner
     }
 
diff --git a/thriller-utils/src/gemm.rs b/thriller-utils/src/gemm.rs
index 50fd072..d76ee23 100644
--- a/thriller-utils/src/gemm.rs
+++ b/thriller-utils/src/gemm.rs
@@ -91,7 +91,7 @@ impl ThrillerUtils {
             vec![Rc::new(in_edge0), Rc::new(in_edge1)],
             vec![Rc::new(out_edge)],
             MemoryLevel::Register,
-            Rc::new(subgraph),
+            Rc::new(RefCell::new(subgraph)),
             BlockType::Reduce,
         );
 
@@ -176,7 +176,7 @@ impl ThrillerUtils {
             vec![Rc::new(in_edge0), Rc::new(in_edge1)],
             vec![Rc::new(out_edge)],
             MemoryLevel::Shared,
-            Rc::new(subgraph),
+            Rc::new(RefCell::new(subgraph)),
             BlockType::Map,
         );