[Syntax Breaking] Rename DefaultImpl to AutoImpl

DefaultImpl is a highly confusing name for what we now call auto impls,
as in `impl Send for ..`. The name auto impl is not formally decided
but for sanity anything is better than `DefaultImpl` which refers
neither to `default impl` nor to `impl Default`.

src/librustc_metadata/cstore_impl.rs

@@ -144,7 +144,7 @@ provide! { <'tcx> tcx, def_id, other, cdata,
     inherent_impls => { Rc::new(cdata.get_inherent_implementations_for_type(def_id.index)) }
     is_const_fn => { cdata.is_const_fn(def_id.index) }
     is_foreign_item => { cdata.is_foreign_item(def_id.index) }
-    is_default_impl => { cdata.is_default_impl(def_id.index) }
+    is_auto_impl => { cdata.is_auto_impl(def_id.index) }
     describe_def => { cdata.get_def(def_id.index) }
     def_span => { cdata.get_span(def_id.index, &tcx.sess) }
     lookup_stability => {

src/librustc_metadata/decoder.rs

@@ -459,7 +459,7 @@ impl<'tcx> EntryKind<'tcx> {
 
             EntryKind::ForeignMod |
             EntryKind::Impl(_) |
-            EntryKind::DefaultImpl(_) |
+            EntryKind::AutoImpl(_) |
             EntryKind::Field |
             EntryKind::Generator(_) |
             EntryKind::Closure(_) => return None,
@@ -529,7 +529,7 @@ impl<'a, 'tcx> CrateMetadata {
         ty::TraitDef::new(self.local_def_id(item_id),
                           data.unsafety,
                           data.paren_sugar,
-                          data.has_default_impl,
+                          data.has_auto_impl,
                           self.def_path_table.def_path_hash(item_id))
     }
 
@@ -735,7 +735,7 @@ impl<'a, 'tcx> CrateMetadata {
                         continue;
                     }
                     EntryKind::Impl(_) |
-                    EntryKind::DefaultImpl(_) => continue,
+                    EntryKind::AutoImpl(_) => continue,
 
                     _ => {}
                 }
@@ -1082,9 +1082,9 @@ impl<'a, 'tcx> CrateMetadata {
         self.dllimport_foreign_items.contains(&id)
     }
 
-    pub fn is_default_impl(&self, impl_id: DefIndex) -> bool {
+    pub fn is_auto_impl(&self, impl_id: DefIndex) -> bool {
         match self.entry(impl_id).kind {
-            EntryKind::DefaultImpl(_) => true,
+            EntryKind::AutoImpl(_) => true,
             _ => false,
         }
     }

src/librustc_metadata/encoder.rs

@@ -919,7 +919,7 @@ impl<'a, 'b: 'a, 'tcx: 'b> IsolatedEncoder<'a, 'b, 'tcx> {
                     ctor_sig: None,
                 }), repr_options)
             }
-            hir::ItemDefaultImpl(..) => {
+            hir::ItemAutoImpl(..) => {
                 let data = ImplData {
                     polarity: hir::ImplPolarity::Positive,
                     defaultness: hir::Defaultness::Final,
@@ -928,7 +928,7 @@ impl<'a, 'b: 'a, 'tcx: 'b> IsolatedEncoder<'a, 'b, 'tcx> {
                     trait_ref: tcx.impl_trait_ref(def_id).map(|trait_ref| self.lazy(&trait_ref)),
                 };
 
-                EntryKind::DefaultImpl(self.lazy(&data))
+                EntryKind::AutoImpl(self.lazy(&data))
             }
             hir::ItemImpl(_, polarity, defaultness, ..) => {
                 let trait_ref = tcx.impl_trait_ref(def_id);
@@ -970,7 +970,7 @@ impl<'a, 'b: 'a, 'tcx: 'b> IsolatedEncoder<'a, 'b, 'tcx> {
                 let data = TraitData {
                     unsafety: trait_def.unsafety,
                     paren_sugar: trait_def.paren_sugar,
-                    has_default_impl: tcx.trait_has_default_impl(def_id),
+                    has_auto_impl: tcx.trait_has_auto_impl(def_id),
                     super_predicates: self.lazy(&tcx.super_predicates_of(def_id)),
                 };
 
@@ -1517,7 +1517,7 @@ impl<'a, 'b, 'tcx> IndexBuilder<'a, 'b, 'tcx> {
             hir::ItemGlobalAsm(..) |
             hir::ItemExternCrate(..) |
             hir::ItemUse(..) |
-            hir::ItemDefaultImpl(..) |
+            hir::ItemAutoImpl(..) |
             hir::ItemTy(..) => {
                 // no sub-item recording needed in these cases
             }

src/librustc_metadata/schema.rs

@@ -303,7 +303,7 @@ pub enum EntryKind<'tcx> {
     Generator(Lazy<GeneratorData<'tcx>>),
     Trait(Lazy<TraitData<'tcx>>),
     Impl(Lazy<ImplData<'tcx>>),
-    DefaultImpl(Lazy<ImplData<'tcx>>),
+    AutoImpl(Lazy<ImplData<'tcx>>),
     Method(Lazy<MethodData<'tcx>>),
     AssociatedType(AssociatedContainer),
     AssociatedConst(AssociatedContainer, u8),
@@ -359,7 +359,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for EntryKind<'gcx> {
             EntryKind::Trait(ref trait_data) => {
                 trait_data.hash_stable(hcx, hasher);
             }
-            EntryKind::DefaultImpl(ref impl_data) |
+            EntryKind::AutoImpl(ref impl_data) |
             EntryKind::Impl(ref impl_data) => {
                 impl_data.hash_stable(hcx, hasher);
             }
@@ -426,14 +426,14 @@ impl_stable_hash_for!(struct VariantData<'tcx> {
 pub struct TraitData<'tcx> {
     pub unsafety: hir::Unsafety,
     pub paren_sugar: bool,
-    pub has_default_impl: bool,
+    pub has_auto_impl: bool,
     pub super_predicates: Lazy<ty::GenericPredicates<'tcx>>,
 }
 
 impl_stable_hash_for!(struct TraitData<'tcx> {
     unsafety,
     paren_sugar,
-    has_default_impl,
+    has_auto_impl,
     super_predicates
 });