move the `FreeRegionMap` into `TypeckTables`

2 files changed, 32 insertions, 2 deletions

diff --git a/src/librustc_data_structures/lib.rs b/src/librustc_data_structures/lib.rs
index cf6bf1cf1d4..3dce4398f3b 100644
--- a/src/librustc_data_structures/lib.rs
+++ b/src/librustc_data_structures/lib.rs
@@ -28,6 +28,7 @@
 #![feature(shared)]
 #![feature(collections_range)]
 #![feature(collections_bound)]
+#![cfg_attr(stage0,feature(field_init_shorthand))]
 #![feature(nonzero)]
 #![feature(rustc_private)]
 #![feature(staged_api)]
diff --git a/src/librustc_data_structures/transitive_relation.rs b/src/librustc_data_structures/transitive_relation.rs
index e09e260afc8..2bce7faf08c 100644
--- a/src/librustc_data_structures/transitive_relation.rs
+++ b/src/librustc_data_structures/transitive_relation.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 use bitvec::BitMatrix;
+use rustc_serialize::{Encodable, Encoder, Decodable, Decoder};
 use std::cell::RefCell;
 use std::fmt::Debug;
 use std::mem;
@@ -36,10 +37,10 @@ pub struct TransitiveRelation<T: Debug + PartialEq> {
     closure: RefCell<Option<BitMatrix>>,
 }
 
-#[derive(Clone, PartialEq, PartialOrd)]
+#[derive(Clone, PartialEq, PartialOrd, RustcEncodable, RustcDecodable)]
 struct Index(usize);
 
-#[derive(Clone, PartialEq)]
+#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable)]
 struct Edge {
     source: Index,
     target: Index,
@@ -54,6 +55,10 @@ impl<T: Debug + PartialEq> TransitiveRelation<T> {
         }
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.edges.is_empty()
+    }
+
     fn index(&self, a: &T) -> Option<Index> {
         self.elements.iter().position(|e| *e == *a).map(Index)
     }
@@ -305,6 +310,30 @@ fn pare_down(candidates: &mut Vec<usize>, closure: &BitMatrix) {
     }
 }
 
+impl<T> Encodable for TransitiveRelation<T>
+    where T: Encodable + Debug + PartialEq
+{
+    fn encode<E: Encoder>(&self, s: &mut E) -> Result<(), E::Error> {
+        s.emit_struct("TransitiveRelation", 2, |s| {
+            s.emit_struct_field("elements", 0, |s| self.elements.encode(s))?;
+            s.emit_struct_field("edges", 1, |s| self.edges.encode(s))?;
+            Ok(())
+        })
+    }
+}
+
+impl<T> Decodable for TransitiveRelation<T>
+    where T: Decodable + Debug + PartialEq
+{
+    fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+        d.read_struct("TransitiveRelation", 2, |d| {
+            let elements = d.read_struct_field("elements", 0, |d| Decodable::decode(d))?;
+            let edges = d.read_struct_field("edges", 1, |d| Decodable::decode(d))?;
+            Ok(TransitiveRelation { elements, edges, closure: RefCell::new(None) })
+        })
+    }
+}
+
 #[test]
 fn test_one_step() {
     let mut relation = TransitiveRelation::new();