fix specialization caching

Author: Ariel Ben-Yehuda

src/librustc/traits/specialize/mod.rs

@@ -150,8 +150,8 @@ pub fn specializes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              impl1_def_id: DefId,
                              impl2_def_id: DefId) -> bool {
     debug!("specializes({:?}, {:?})", impl1_def_id, impl2_def_id);
-
-    if let Some(r) = tcx.specializes_cache.borrow().check(impl1_def_id, impl2_def_id) {
+    if let Some(r) =
+        tcx.global_tcx().specializes_cache.borrow().check(impl1_def_id, impl2_def_id) {
         return r;
     }
 
@@ -203,7 +203,8 @@ pub fn specializes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         fulfill_implication(&infcx, impl1_trait_ref, impl2_def_id).is_ok()
     });
 
-    tcx.specializes_cache.borrow_mut().insert(impl1_def_id, impl2_def_id, result);
+    tcx.global_tcx().specializes_cache.borrow_mut()
+        .insert(impl1_def_id, impl2_def_id, result);
     result
 }
 

src/librustc/ty/maps.rs

@@ -10,6 +10,7 @@
 
 use dep_graph::{DepGraph, DepNode, DepTrackingMap, DepTrackingMapConfig};
 use hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
+use hir;
 use middle::const_val;
 use middle::privacy::AccessLevels;
 use mir;
@@ -391,6 +392,7 @@ define_maps! { <'tcx>
     pub associated_item: AssociatedItems(DefId) -> ty::AssociatedItem,
 
     pub impl_trait_ref: ItemSignature(DefId) -> Option<ty::TraitRef<'tcx>>,
+    pub impl_polarity: ItemSignature(DefId) -> hir::ImplPolarity,
 
     /// Maps a DefId of a type to a list of its inherent impls.
     /// Contains implementations of methods that are inherent to a type.

src/librustc/ty/mod.rs

@@ -2136,14 +2136,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     }
 
     pub fn trait_impl_polarity(self, id: DefId) -> hir::ImplPolarity {
-        if let Some(id) = self.hir.as_local_node_id(id) {
-            match self.hir.expect_item(id).node {
-                hir::ItemImpl(_, polarity, ..) => polarity,
-                ref item => bug!("trait_impl_polarity: {:?} not an impl", item)
-            }
-        } else {
-            self.sess.cstore.impl_polarity(id)
-        }
+        queries::impl_polarity::get(self, DUMMY_SP, id)
     }
 
     pub fn trait_relevant_for_never(self, did: DefId) -> bool {

src/librustc_metadata/cstore_impl.rs

@@ -89,6 +89,7 @@ provide! { <'tcx> tcx, def_id, cdata
     }
     associated_item => { cdata.get_associated_item(def_id.index) }
     impl_trait_ref => { cdata.get_impl_trait(def_id.index, tcx) }
+    impl_polarity => { cdata.get_impl_polarity(def_id.index) }
     coerce_unsized_info => {
         cdata.get_coerce_unsized_info(def_id.index).unwrap_or_else(|| {
             bug!("coerce_unsized_info: `{:?}` is missing its info", def_id);

src/librustc_typeck/collect.rs

@@ -99,6 +99,7 @@ pub fn provide(providers: &mut Providers) {
         trait_def,
         adt_def,
         impl_trait_ref,
+        impl_polarity,
         ..*providers
     };
 }
@@ -1132,6 +1133,16 @@ fn impl_trait_ref<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     }
 }
 
+fn impl_polarity<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                           def_id: DefId)
+                           -> hir::ImplPolarity {
+    let node_id = tcx.hir.as_local_node_id(def_id).unwrap();
+    match tcx.hir.expect_item(node_id).node {
+        hir::ItemImpl(_, polarity, ..) => polarity,
+        ref item => bug!("trait_impl_polarity: {:?} not an impl", item)
+    }
+}
+
 // Is it marked with ?Sized
 fn is_unsized<'gcx: 'tcx, 'tcx>(astconv: &AstConv<'gcx, 'tcx>,
                                 ast_bounds: &[hir::TyParamBound],