1 files changed, 45 insertions, 0 deletions
diff --git a/compiler/rustc_query_system/src/dep_graph/serialized.rs b/compiler/rustc_query_system/src/dep_graph/serialized.rs
new file mode 100644
index 00000000000..932c6d2a2f1
--- /dev/null
+++ b/compiler/rustc_query_system/src/dep_graph/serialized.rs
@@ -0,0 +1,45 @@
+//! The data that we will serialize and deserialize.
+
+use super::{DepKind, DepNode};
+use rustc_data_structures::fingerprint::Fingerprint;
+use rustc_index::vec::IndexVec;
+
+rustc_index::newtype_index! {
+    pub struct SerializedDepNodeIndex { .. }
+}
+
+/// Data for use when recompiling the **current crate**.
+#[derive(Debug, Encodable, Decodable)]
+pub struct SerializedDepGraph<K: DepKind> {
+    /// The set of all DepNodes in the graph
+    pub nodes: IndexVec<SerializedDepNodeIndex, DepNode<K>>,
+    /// The set of all Fingerprints in the graph. Each Fingerprint corresponds to
+    /// the DepNode at the same index in the nodes vector.
+    pub fingerprints: IndexVec<SerializedDepNodeIndex, Fingerprint>,
+    /// For each DepNode, stores the list of edges originating from that
+    /// DepNode. Encoded as a [start, end) pair indexing into edge_list_data,
+    /// which holds the actual DepNodeIndices of the target nodes.
+    pub edge_list_indices: IndexVec<SerializedDepNodeIndex, (u32, u32)>,
+    /// A flattened list of all edge targets in the graph. Edge sources are
+    /// implicit in edge_list_indices.
+    pub edge_list_data: Vec<SerializedDepNodeIndex>,
+}
+
+impl<K: DepKind> Default for SerializedDepGraph<K> {
+    fn default() -> Self {
+        SerializedDepGraph {
+            nodes: Default::default(),
+            fingerprints: Default::default(),
+            edge_list_indices: Default::default(),
+            edge_list_data: Default::default(),
+        }
+    }
+}
+
+impl<K: DepKind> SerializedDepGraph<K> {
+    #[inline]
+    pub fn edge_targets_from(&self, source: SerializedDepNodeIndex) -> &[SerializedDepNodeIndex] {
+        let targets = self.edge_list_indices[source];
+        &self.edge_list_data[targets.0 as usize..targets.1 as usize]
+    }
+}