Use lookup_locally_or_in_crate_store more often

5 files changed, 54 insertions, 88 deletions

diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index e6591789a74..0908ffd249f 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -1215,11 +1215,11 @@ fn encode_info_for_item(ecx: &EncodeContext,
           encode_name(rbml_w, item.ident.name);
           encode_unsafety(rbml_w, unsafety);
 
-          let trait_ref = ty::impl_id_to_trait_ref(tcx, item.id);
+          let trait_ref = ty::impl_trait_ref(tcx, local_def(item.id)).unwrap();
           encode_trait_ref(rbml_w, ecx, trait_ref, tag_item_trait_ref);
           rbml_w.end_tag();
       }
-      ast::ItemImpl(unsafety, polarity, _, ref opt_trait, ref ty, ref ast_items) => {
+      ast::ItemImpl(unsafety, polarity, _, _, ref ty, ref ast_items) => {
         // We need to encode information about the default methods we
         // have inherited, so we drive this based on the impl structure.
         let impl_items = tcx.impl_items.borrow();
@@ -1269,8 +1269,7 @@ fn encode_info_for_item(ecx: &EncodeContext,
             }
             rbml_w.end_tag();
         }
-        if opt_trait.is_some() {
-            let trait_ref = ty::impl_id_to_trait_ref(tcx, item.id);
+        if let Some(trait_ref) = ty::impl_trait_ref(tcx, local_def(item.id)) {
             encode_trait_ref(rbml_w, ecx, trait_ref, tag_item_trait_ref);
         }
         encode_path(rbml_w, path.clone());
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index 64a82fec05c..4a95320b3f7 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -650,9 +650,7 @@ pub struct ctxt<'tcx> {
     /// A cache for the trait_items() routine
     pub trait_items_cache: RefCell<DefIdMap<Rc<Vec<ImplOrTraitItem<'tcx>>>>>,
 
-    pub impl_trait_cache: RefCell<DefIdMap<Option<TraitRef<'tcx>>>>,
-
-    pub impl_trait_refs: RefCell<NodeMap<TraitRef<'tcx>>>,
+    pub impl_trait_refs: RefCell<DefIdMap<Option<TraitRef<'tcx>>>>,
     pub trait_defs: RefCell<DefIdMap<&'tcx TraitDef<'tcx>>>,
 
     /// Maps from the def-id of an item (trait/struct/enum/fn) to its
@@ -675,7 +673,6 @@ pub struct ctxt<'tcx> {
     pub freevars: RefCell<FreevarMap>,
     pub tcache: RefCell<DefIdMap<TypeScheme<'tcx>>>,
     pub rcache: RefCell<FnvHashMap<creader_cache_key, Ty<'tcx>>>,
-    pub short_names_cache: RefCell<FnvHashMap<Ty<'tcx>, String>>,
     pub tc_cache: RefCell<FnvHashMap<Ty<'tcx>, TypeContents>>,
     pub ast_ty_to_ty_cache: RefCell<NodeMap<Ty<'tcx>>>,
     pub enum_var_cache: RefCell<DefIdMap<Rc<Vec<Rc<VariantInfo<'tcx>>>>>>,
@@ -2741,7 +2738,7 @@ pub fn mk_ctxt<'tcx>(s: Session,
         def_map: def_map,
         node_types: RefCell::new(FnvHashMap()),
         item_substs: RefCell::new(NodeMap()),
-        impl_trait_refs: RefCell::new(NodeMap()),
+        impl_trait_refs: RefCell::new(DefIdMap()),
         trait_defs: RefCell::new(DefIdMap()),
         predicates: RefCell::new(DefIdMap()),
         super_predicates: RefCell::new(DefIdMap()),
@@ -2750,14 +2747,12 @@ pub fn mk_ctxt<'tcx>(s: Session,
         freevars: freevars,
         tcache: RefCell::new(DefIdMap()),
         rcache: RefCell::new(FnvHashMap()),
-        short_names_cache: RefCell::new(FnvHashMap()),
         tc_cache: RefCell::new(FnvHashMap()),
         ast_ty_to_ty_cache: RefCell::new(NodeMap()),
         enum_var_cache: RefCell::new(DefIdMap()),
         impl_or_trait_items: RefCell::new(DefIdMap()),
         trait_item_def_ids: RefCell::new(DefIdMap()),
         trait_items_cache: RefCell::new(DefIdMap()),
-        impl_trait_cache: RefCell::new(DefIdMap()),
         ty_param_defs: RefCell::new(NodeMap()),
         adjustments: RefCell::new(NodeMap()),
         normalized_cache: RefCell::new(FnvHashMap()),
@@ -4464,16 +4459,6 @@ pub fn named_element_ty<'tcx>(cx: &ctxt<'tcx>,
     }
 }
 
-pub fn impl_id_to_trait_ref<'tcx>(cx: &ctxt<'tcx>, id: ast::NodeId)
-                                  -> ty::TraitRef<'tcx> {
-    match cx.impl_trait_refs.borrow().get(&id) {
-        Some(ty) => *ty,
-        None => cx.sess.bug(
-            &format!("impl_id_to_trait_ref: no trait ref for impl `{}`",
-                    cx.map.node_to_string(id)))
-    }
-}
-
 pub fn node_id_to_type<'tcx>(cx: &ctxt<'tcx>, id: ast::NodeId) -> Ty<'tcx> {
     match node_id_to_type_opt(cx, id) {
        Some(ty) => ty,
@@ -5268,12 +5253,12 @@ pub fn associated_consts<'tcx>(cx: &ctxt<'tcx>, id: ast::DefId)
 /// the future).
 fn lookup_locally_or_in_crate_store<V, F>(descr: &str,
                                           def_id: ast::DefId,
-                                          map: &mut DefIdMap<V>,
+                                          map: &RefCell<DefIdMap<V>>,
                                           load_external: F) -> V where
     V: Clone,
     F: FnOnce() -> V,
 {
-    match map.get(&def_id).cloned() {
+    match map.borrow().get(&def_id).cloned() {
         Some(v) => { return v; }
         None => { }
     }
@@ -5282,7 +5267,7 @@ fn lookup_locally_or_in_crate_store<V, F>(descr: &str,
         panic!("No def'n found for {:?} in tcx.{}", def_id, descr);
     }
     let v = load_external();
-    map.insert(def_id, v.clone());
+    map.borrow_mut().insert(def_id, v.clone());
     v
 }
 
@@ -5348,13 +5333,9 @@ pub fn custom_coerce_unsized_kind<'tcx>(cx: &ctxt<'tcx>, did: ast::DefId)
 
 pub fn impl_or_trait_item<'tcx>(cx: &ctxt<'tcx>, id: ast::DefId)
                                 -> ImplOrTraitItem<'tcx> {
-    lookup_locally_or_in_crate_store("impl_or_trait_items",
-                                     id,
-                                     &mut *cx.impl_or_trait_items
-                                             .borrow_mut(),
-                                     || {
-        csearch::get_impl_or_trait_item(cx, id)
-    })
+    lookup_locally_or_in_crate_store(
+        "impl_or_trait_items", id, &cx.impl_or_trait_items,
+        || csearch::get_impl_or_trait_item(cx, id))
 }
 
 /// Returns the parameter index that the given associated type corresponds to.
@@ -5881,37 +5862,35 @@ pub fn lookup_item_type<'tcx>(cx: &ctxt<'tcx>,
                               did: ast::DefId)
                               -> TypeScheme<'tcx> {
     lookup_locally_or_in_crate_store(
-        "tcache", did, &mut *cx.tcache.borrow_mut(),
+        "tcache", did, &cx.tcache,
         || csearch::get_type(cx, did))
 }
 
 /// Given the did of a trait, returns its canonical trait ref.
 pub fn lookup_trait_def<'tcx>(cx: &ctxt<'tcx>, did: ast::DefId)
                               -> &'tcx TraitDef<'tcx> {
-    memoized(&cx.trait_defs, did, |did: DefId| {
-        assert!(did.krate != ast::LOCAL_CRATE);
-        cx.arenas.trait_defs.alloc(csearch::get_trait_def(cx, did))
-    })
+    lookup_locally_or_in_crate_store(
+        "trait_defs", did, &cx.trait_defs,
+        || cx.arenas.trait_defs.alloc(csearch::get_trait_def(cx, did))
+    )
 }
 
 /// Given the did of an item, returns its full set of predicates.
 pub fn lookup_predicates<'tcx>(cx: &ctxt<'tcx>, did: ast::DefId)
                                 -> GenericPredicates<'tcx>
 {
-    memoized(&cx.predicates, did, |did: DefId| {
-        assert!(did.krate != ast::LOCAL_CRATE);
-        csearch::get_predicates(cx, did)
-    })
+    lookup_locally_or_in_crate_store(
+        "predicates", did, &cx.predicates,
+        || csearch::get_predicates(cx, did))
 }
 
 /// Given the did of a trait, returns its superpredicates.
 pub fn lookup_super_predicates<'tcx>(cx: &ctxt<'tcx>, did: ast::DefId)
                                      -> GenericPredicates<'tcx>
 {
-    memoized(&cx.super_predicates, did, |did: DefId| {
-        assert!(did.krate != ast::LOCAL_CRATE);
-        csearch::get_super_predicates(cx, did)
-    })
+    lookup_locally_or_in_crate_store(
+        "super_predicates", did, &cx.super_predicates,
+        || csearch::get_super_predicates(cx, did))
 }
 
 pub fn predicates<'tcx>(
@@ -6281,7 +6260,7 @@ pub fn required_region_bounds<'tcx>(tcx: &ctxt<'tcx>,
 
 pub fn item_variances(tcx: &ctxt, item_id: ast::DefId) -> Rc<ItemVariances> {
     lookup_locally_or_in_crate_store(
-        "item_variance_map", item_id, &mut *tcx.item_variance_map.borrow_mut(),
+        "item_variance_map", item_id, &tcx.item_variance_map,
         || Rc::new(csearch::get_item_variances(&tcx.sess.cstore, item_id)))
 }
 
diff --git a/src/librustc_typeck/check/wf.rs b/src/librustc_typeck/check/wf.rs
index 79736c08f37..8ec406ff41b 100644
--- a/src/librustc_typeck/check/wf.rs
+++ b/src/librustc_typeck/check/wf.rs
@@ -81,7 +81,8 @@ impl<'ccx, 'tcx> CheckTypeWellFormedVisitor<'ccx, 'tcx> {
                 self.check_impl(item);
             }
             ast::ItemImpl(_, ast::ImplPolarity::Negative, _, Some(_), _, _) => {
-                let trait_ref = ty::impl_id_to_trait_ref(ccx.tcx, item.id);
+                let trait_ref = ty::impl_trait_ref(ccx.tcx,
+                                                   local_def(item.id)).unwrap();
                 ty::populate_implementations_for_trait_if_necessary(ccx.tcx, trait_ref.def_id);
                 match ccx.tcx.lang_items.to_builtin_kind(trait_ref.def_id) {
                     Some(ty::BoundSend) | Some(ty::BoundSync) => {}
diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs
index 58ad8ce8628..622c116cdb9 100644
--- a/src/librustc_typeck/coherence/mod.rs
+++ b/src/librustc_typeck/coherence/mod.rs
@@ -36,7 +36,7 @@ use std::cell::RefCell;
 use std::rc::Rc;
 use syntax::ast::{Crate, DefId};
 use syntax::ast::{Item, ItemImpl};
-use syntax::ast::{LOCAL_CRATE, TraitRef};
+use syntax::ast::{LOCAL_CRATE};
 use syntax::ast;
 use syntax::ast_map::NodeItem;
 use syntax::ast_map;
@@ -100,11 +100,8 @@ struct CoherenceCheckVisitor<'a, 'tcx: 'a> {
 
 impl<'a, 'tcx, 'v> visit::Visitor<'v> for CoherenceCheckVisitor<'a, 'tcx> {
     fn visit_item(&mut self, item: &Item) {
-
-        //debug!("(checking coherence) item '{}'", token::get_ident(item.ident));
-
-        if let ItemImpl(_, _, _, ref opt_trait, _, _) = item.node {
-            self.cc.check_implementation(item, opt_trait.as_ref())
+        if let ItemImpl(..) = item.node {
+            self.cc.check_implementation(item)
         }
 
         visit::walk_item(self, item);
@@ -141,7 +138,7 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
         self.check_implementations_of_coerce_unsized();
     }
 
-    fn check_implementation(&self, item: &Item, opt_trait: Option<&TraitRef>) {
+    fn check_implementation(&self, item: &Item) {
         let tcx = self.crate_context.tcx;
         let impl_did = local_def(item.id);
         let self_type = ty::lookup_item_type(tcx, impl_did);
@@ -151,8 +148,8 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
 
         let impl_items = self.create_impl_from_item(item);
 
-        if opt_trait.is_some() {
-            let trait_ref = ty::impl_id_to_trait_ref(self.crate_context.tcx, item.id);
+        if let Some(trait_ref) = ty::impl_trait_ref(self.crate_context.tcx,
+                                                    impl_did) {
             debug!("(checking implementation) adding impl for trait '{}', item '{}'",
                    trait_ref.repr(self.crate_context.tcx),
                    token::get_ident(item.ident));
@@ -161,22 +158,13 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
                                                  item.span,
                                                  trait_ref.def_id);
             self.add_trait_impl(trait_ref, impl_did);
-        }
-
-        // Add the implementation to the mapping from implementation to base
-        // type def ID, if there is a base type for this implementation and
-        // the implementation does not have any associated traits.
-        match get_base_type_def_id(&self.inference_context,
-                                   item.span,
-                                   self_type.ty) {
-            None => {
-                // Nothing to do.
-            }
-            Some(base_type_def_id) => {
-                // FIXME: Gather up default methods?
-                if opt_trait.is_none() {
-                    self.add_inherent_impl(base_type_def_id, impl_did);
-                }
+        } else {
+            // Add the implementation to the mapping from implementation to base
+            // type def ID, if there is a base type for this implementation and
+            // the implementation does not have any associated traits.
+            if let Some(base_type_def_id) = get_base_type_def_id(
+                    &self.inference_context, item.span, self_type.ty) {
+                self.add_inherent_impl(base_type_def_id, impl_did);
             }
         }
 
@@ -267,7 +255,7 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
     // Converts an implementation in the AST to a vector of items.
     fn create_impl_from_item(&self, item: &Item) -> Vec<ImplOrTraitItemId> {
         match item.node {
-            ItemImpl(_, _, _, ref opt_trait, _, ref impl_items) => {
+            ItemImpl(_, _, _, _, _, ref impl_items) => {
                 let mut items: Vec<ImplOrTraitItemId> =
                         impl_items.iter().map(|impl_item| {
                     match impl_item.node {
@@ -287,10 +275,8 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
                     }
                 }).collect();
 
-                if opt_trait.is_some() {
-                    let trait_ref = ty::impl_id_to_trait_ref(self.crate_context.tcx,
-                                                             item.id);
-
+                if let Some(trait_ref) = ty::impl_trait_ref(self.crate_context.tcx,
+                                                            local_def(item.id)) {
                     self.instantiate_default_methods(local_def(item.id),
                                                      &trait_ref,
                                                      &mut items);
@@ -453,8 +439,8 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> {
             }
 
             let source = ty::lookup_item_type(tcx, impl_did).ty;
-            let trait_ref = ty::impl_id_to_trait_ref(self.crate_context.tcx,
-                                                     impl_did.node);
+            let trait_ref = ty::impl_trait_ref(self.crate_context.tcx,
+                                               impl_did).unwrap();
             let target = *trait_ref.substs.types.get(subst::TypeSpace, 0);
             debug!("check_implementations_of_coerce_unsized: {} -> {} (bound)",
                    source.repr(tcx), target.repr(tcx));
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 48876c2a188..2fba967b3b2 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -820,7 +820,7 @@ fn convert_item(ccx: &CrateCtxt, it: &ast::Item) {
 
             ty::record_trait_has_default_impl(tcx, trait_ref.def_id);
 
-            tcx.impl_trait_refs.borrow_mut().insert(it.id, trait_ref);
+            tcx.impl_trait_refs.borrow_mut().insert(local_def(it.id), Some(trait_ref));
         }
         ast::ItemImpl(_, _,
                       ref generics,
@@ -828,7 +828,6 @@ fn convert_item(ccx: &CrateCtxt, it: &ast::Item) {
                       ref selfty,
                       ref impl_items) => {
             // Create generics from the generics specified in the impl head.
-
             debug!("convert: ast_generics={:?}", generics);
             let ty_generics = ty_generics_for_type_or_impl(ccx, generics);
             let ty_predicates = ty_generic_predicates_for_type_or_impl(ccx, generics);
@@ -926,14 +925,16 @@ fn convert_item(ccx: &CrateCtxt, it: &ast::Item) {
                 }
             }
 
-            if let Some(ref ast_trait_ref) = *opt_trait_ref {
-                let trait_ref =
-                    astconv::instantiate_mono_trait_ref(&ccx.icx(&ty_predicates),
-                                                        &ExplicitRscope,
-                                                        ast_trait_ref,
-                                                        Some(selfty));
-
-                tcx.impl_trait_refs.borrow_mut().insert(it.id, trait_ref);
+            if let &Some(ref ast_trait_ref) = opt_trait_ref {
+                tcx.impl_trait_refs.borrow_mut().insert(
+                    local_def(it.id),
+                    Some(astconv::instantiate_mono_trait_ref(&ccx.icx(&ty_predicates),
+                                                             &ExplicitRscope,
+                                                             ast_trait_ref,
+                                                             Some(selfty)))
+                        );
+            } else {
+                tcx.impl_trait_refs.borrow_mut().insert(local_def(it.id), None);
             }
 
             enforce_impl_params_are_constrained(tcx,