Rework `rustc_serialize`

- Move the type parameter from `encode` and `decode` methods to
  the trait.
- Remove `UseSpecialized(En|De)codable` traits.
- Remove blanket impls for references.
- Add `RefDecodable` trait to allow deserializing to arena-allocated
  references safely.
- Remove ability to (de)serialize HIR.
- Create proc-macros `(Ty)?(En|De)codable` to help implement these new
  traits.

6 files changed, 9 insertions, 5 deletions

diff --git a/src/librustc_query_system/Cargo.toml b/src/librustc_query_system/Cargo.toml
index 64af9c5f1a1..c1ec452e001 100644
--- a/src/librustc_query_system/Cargo.toml
+++ b/src/librustc_query_system/Cargo.toml
@@ -15,6 +15,7 @@ log = { package = "tracing", version = "0.1" }
 rustc-rayon-core = "0.3.0"
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_errors = { path = "../librustc_errors" }
+rustc_macros = { path = "../librustc_macros" }
 rustc_index = { path = "../librustc_index" }
 rustc_serialize = { path = "../librustc_serialize" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_query_system/dep_graph/dep_node.rs b/src/librustc_query_system/dep_graph/dep_node.rs
index 002b0f9c165..e302784cc3e 100644
--- a/src/librustc_query_system/dep_graph/dep_node.rs
+++ b/src/librustc_query_system/dep_graph/dep_node.rs
@@ -50,7 +50,7 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use std::fmt;
 use std::hash::Hash;
 
-#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Encodable, Decodable)]
 pub struct DepNode<K> {
     pub kind: K,
     pub hash: Fingerprint,
@@ -152,7 +152,8 @@ impl<Ctxt: DepContext> DepNodeParams<Ctxt> for () {
 /// some independent path or string that persists between runs without
 /// the need to be mapped or unmapped. (This ensures we can serialize
 /// them even in the absence of a tcx.)
-#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Encodable, Decodable)]
 pub struct WorkProductId {
     hash: Fingerprint,
 }
diff --git a/src/librustc_query_system/dep_graph/graph.rs b/src/librustc_query_system/dep_graph/graph.rs
index 04a45090b72..d70306b4869 100644
--- a/src/librustc_query_system/dep_graph/graph.rs
+++ b/src/librustc_query_system/dep_graph/graph.rs
@@ -857,7 +857,7 @@ impl<K: DepKind> DepGraph<K> {
 /// may be added -- for example, new monomorphizations -- even if
 /// nothing in P changed!). We will compare that hash against the
 /// previous hash. If it matches up, we can reuse the object file.
-#[derive(Clone, Debug, RustcEncodable, RustcDecodable)]
+#[derive(Clone, Debug, Encodable, Decodable)]
 pub struct WorkProduct {
     pub cgu_name: String,
     /// Saved file associated with this CGU.
diff --git a/src/librustc_query_system/dep_graph/prev.rs b/src/librustc_query_system/dep_graph/prev.rs
index 5cba64cac4b..29357ce9449 100644
--- a/src/librustc_query_system/dep_graph/prev.rs
+++ b/src/librustc_query_system/dep_graph/prev.rs
@@ -3,7 +3,7 @@ use super::{DepKind, DepNode};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
 
-#[derive(Debug, RustcEncodable, RustcDecodable)]
+#[derive(Debug, Encodable, Decodable)]
 pub struct PreviousDepGraph<K: DepKind> {
     data: SerializedDepGraph<K>,
     index: FxHashMap<DepNode<K>, SerializedDepNodeIndex>,
diff --git a/src/librustc_query_system/dep_graph/serialized.rs b/src/librustc_query_system/dep_graph/serialized.rs
index 4a89da23ea6..932c6d2a2f1 100644
--- a/src/librustc_query_system/dep_graph/serialized.rs
+++ b/src/librustc_query_system/dep_graph/serialized.rs
@@ -9,7 +9,7 @@ rustc_index::newtype_index! {
 }
 
 /// Data for use when recompiling the **current crate**.
-#[derive(Debug, RustcEncodable, RustcDecodable)]
+#[derive(Debug, Encodable, Decodable)]
 pub struct SerializedDepGraph<K: DepKind> {
     /// The set of all DepNodes in the graph
     pub nodes: IndexVec<SerializedDepNodeIndex, DepNode<K>>,
diff --git a/src/librustc_query_system/lib.rs b/src/librustc_query_system/lib.rs
index 4bbba7befe9..db104398f16 100644
--- a/src/librustc_query_system/lib.rs
+++ b/src/librustc_query_system/lib.rs
@@ -10,6 +10,8 @@
 extern crate log;
 #[macro_use]
 extern crate rustc_data_structures;
+#[macro_use]
+extern crate rustc_macros;
 
 pub mod cache;
 pub mod dep_graph;