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.

3 files changed, 8 insertions, 5 deletions

diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index 8fa0de37648..ff9dac372ab 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -33,5 +33,6 @@ rustc_fs_util = { path = "../librustc_fs_util" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_incremental = { path = "../librustc_incremental" }
 rustc_index = { path = "../librustc_index" }
+rustc_macros = { path = "../librustc_macros" }
 rustc_target = { path = "../librustc_target" }
 rustc_session = { path = "../librustc_session" }
diff --git a/src/librustc_codegen_ssa/back/linker.rs b/src/librustc_codegen_ssa/back/linker.rs
index f9a782af24c..5100ef8ad4f 100644
--- a/src/librustc_codegen_ssa/back/linker.rs
+++ b/src/librustc_codegen_ssa/back/linker.rs
@@ -35,7 +35,7 @@ pub fn disable_localization(linker: &mut Command) {
 
 /// For all the linkers we support, and information they might
 /// need out of the shared crate context before we get rid of it.
-#[derive(RustcEncodable, RustcDecodable)]
+#[derive(Encodable, Decodable)]
 pub struct LinkerInfo {
     exports: FxHashMap<CrateType, Vec<String>>,
 }
diff --git a/src/librustc_codegen_ssa/lib.rs b/src/librustc_codegen_ssa/lib.rs
index 85260d30a3d..6bfbda0f1d7 100644
--- a/src/librustc_codegen_ssa/lib.rs
+++ b/src/librustc_codegen_ssa/lib.rs
@@ -17,6 +17,8 @@
 //! have to be implemented by each backends.
 
 #[macro_use]
+extern crate rustc_macros;
+#[macro_use]
 extern crate log;
 #[macro_use]
 extern crate rustc_middle;
@@ -74,7 +76,7 @@ impl<M> ModuleCodegen<M> {
     }
 }
 
-#[derive(Debug, RustcEncodable, RustcDecodable)]
+#[derive(Debug, Encodable, Decodable)]
 pub struct CompiledModule {
     pub name: String,
     pub kind: ModuleKind,
@@ -87,7 +89,7 @@ pub struct CachedModuleCodegen {
     pub source: WorkProduct,
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
+#[derive(Copy, Clone, Debug, PartialEq, Encodable, Decodable)]
 pub enum ModuleKind {
     Regular,
     Metadata,
@@ -110,7 +112,7 @@ bitflags::bitflags! {
 /// identifiers (`CrateNum`) to `CrateSource`. The other fields map `CrateNum` to the crate's own
 /// additional properties, so that effectively we can retrieve each dependent crate's `CrateSource`
 /// and the corresponding properties without referencing information outside of a `CrateInfo`.
-#[derive(Debug, RustcEncodable, RustcDecodable)]
+#[derive(Debug, Encodable, Decodable)]
 pub struct CrateInfo {
     pub panic_runtime: Option<CrateNum>,
     pub compiler_builtins: Option<CrateNum>,
@@ -128,7 +130,7 @@ pub struct CrateInfo {
     pub dependency_formats: Lrc<Dependencies>,
 }
 
-#[derive(RustcEncodable, RustcDecodable)]
+#[derive(Encodable, Decodable)]
 pub struct CodegenResults {
     pub crate_name: Symbol,
     pub modules: Vec<CompiledModule>,