1 files changed, 4 insertions, 43 deletions

diff --git a/compiler/rustc_span/src/def_id.rs b/compiler/rustc_span/src/def_id.rs
index e397fab5459..b498202dc92 100644
--- a/compiler/rustc_span/src/def_id.rs
+++ b/compiler/rustc_span/src/def_id.rs
@@ -1,11 +1,11 @@
-use crate::{HashStableContext, Symbol};
+use crate::{HashStableContext, SpanDecoder, SpanEncoder, Symbol};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::stable_hasher::{Hash64, HashStable, StableHasher, ToStableHashKey};
 use rustc_data_structures::unhash::Unhasher;
 use rustc_data_structures::AtomicRef;
 use rustc_index::Idx;
 use rustc_macros::HashStable_Generic;
-use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_serialize::{Decodable, Encodable};
 use std::fmt;
 use std::hash::{BuildHasherDefault, Hash, Hasher};
 
@@ -46,20 +46,6 @@ impl fmt::Display for CrateNum {
     }
 }
 
-/// As a local identifier, a `CrateNum` is only meaningful within its context, e.g. within a tcx.
-/// Therefore, make sure to include the context when encode a `CrateNum`.
-impl<E: Encoder> Encodable<E> for CrateNum {
-    default fn encode(&self, s: &mut E) {
-        s.emit_u32(self.as_u32());
-    }
-}
-
-impl<D: Decoder> Decodable<D> for CrateNum {
-    default fn decode(d: &mut D) -> CrateNum {
-        CrateNum::from_u32(d.read_u32())
-    }
-}
-
 /// A `DefPathHash` is a fixed-size representation of a `DefPath` that is
 /// stable across crate and compilation session boundaries. It consists of two
 /// separate 64-bit hashes. The first uniquely identifies the crate this
@@ -220,18 +206,6 @@ rustc_index::newtype_index! {
     }
 }
 
-impl<E: Encoder> Encodable<E> for DefIndex {
-    default fn encode(&self, _: &mut E) {
-        panic!("cannot encode `DefIndex` with `{}`", std::any::type_name::<E>());
-    }
-}
-
-impl<D: Decoder> Decodable<D> for DefIndex {
-    default fn decode(_: &mut D) -> DefIndex {
-        panic!("cannot decode `DefIndex` with `{}`", std::any::type_name::<D>());
-    }
-}
-
 /// A `DefId` identifies a particular *definition*, by combining a crate
 /// index and a def index.
 ///
@@ -347,19 +321,6 @@ impl From<LocalDefId> for DefId {
     }
 }
 
-impl<E: Encoder> Encodable<E> for DefId {
-    default fn encode(&self, s: &mut E) {
-        self.krate.encode(s);
-        self.index.encode(s);
-    }
-}
-
-impl<D: Decoder> Decodable<D> for DefId {
-    default fn decode(d: &mut D) -> DefId {
-        DefId { krate: Decodable::decode(d), index: Decodable::decode(d) }
-    }
-}
-
 pub fn default_def_id_debug(def_id: DefId, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     f.debug_struct("DefId").field("krate", &def_id.krate).field("index", &def_id.index).finish()
 }
@@ -423,13 +384,13 @@ impl fmt::Debug for LocalDefId {
     }
 }
 
-impl<E: Encoder> Encodable<E> for LocalDefId {
+impl<E: SpanEncoder> Encodable<E> for LocalDefId {
     fn encode(&self, s: &mut E) {
         self.to_def_id().encode(s);
     }
 }
 
-impl<D: Decoder> Decodable<D> for LocalDefId {
+impl<D: SpanDecoder> Decodable<D> for LocalDefId {
     fn decode(d: &mut D) -> LocalDefId {
         DefId::decode(d).expect_local()
     }