Rollup merge of rust-lang#41724 - achernyak:master, r=nikomatsakis

More Queries for Crate Metadata

This covers a little bit of clean up and the following parts of rust-lang#41417:
* `fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute>;`
* `fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name>;`
* `fn trait_of_item(&self, def_id: DefId) -> Option<DefId>;`
* `fn impl_parent(&self, impl_def_id: DefId) -> Option<DefId>;`
* ` fn is_foreign_item(&self, did: DefId) -> bool;`
* `fn is_exported_symbol(&self, def_id: DefId) -> bool;`

r? @nikomatsakis

src/librustc/dep_graph/dep_node.rs

@@ -159,6 +159,14 @@ pub enum DepNode<D: Clone + Debug> {
     DefSpan(D),
     Stability(D),
     Deprecation(D),
+    ItemBodyNestedBodies(D),
+    ConstIsRvaluePromotableToStatic(D),
+    ImplParent(D),
+    TraitOfItem(D),
+    IsExportedSymbol(D),
+    IsMirAvailable(D),
+    ItemAttrs(D),
+    FnArgNames(D),
     FileMap(D, Arc<String>),
 }
 
@@ -273,6 +281,14 @@ impl<D: Clone + Debug> DepNode<D> {
             DefSpan(ref d) => op(d).map(DefSpan),
             Stability(ref d) => op(d).map(Stability),
             Deprecation(ref d) => op(d).map(Deprecation),
+            ItemAttrs(ref d) => op(d).map(ItemAttrs),
+            FnArgNames(ref d) => op(d).map(FnArgNames),
+            ImplParent(ref d) => op(d).map(ImplParent),
+            TraitOfItem(ref d) => op(d).map(TraitOfItem),
+            IsExportedSymbol(ref d) => op(d).map(IsExportedSymbol),
+            ItemBodyNestedBodies(ref d) => op(d).map(ItemBodyNestedBodies),
+            ConstIsRvaluePromotableToStatic(ref d) => op(d).map(ConstIsRvaluePromotableToStatic),
+            IsMirAvailable(ref d) => op(d).map(IsMirAvailable),
             GlobalMetaData(ref d, kind) => op(d).map(|d| GlobalMetaData(d, kind)),
             FileMap(ref d, ref file_name) => op(d).map(|d| FileMap(d, file_name.clone())),
         }

src/librustc/middle/cstore.rs

@@ -210,27 +210,21 @@ pub trait CrateStore {
     fn visibility(&self, def: DefId) -> ty::Visibility;
     fn visible_parent_map<'a>(&'a self) -> ::std::cell::Ref<'a, DefIdMap<DefId>>;
     fn item_generics_cloned(&self, def: DefId) -> ty::Generics;
-    fn item_attrs(&self, def_id: DefId) -> Rc<[ast::Attribute]>;
-    fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name>;
 
     // trait info
     fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId>;
 
     // impl info
     fn impl_defaultness(&self, def: DefId) -> hir::Defaultness;
-    fn impl_parent(&self, impl_def_id: DefId) -> Option<DefId>;
 
     // trait/impl-item info
-    fn trait_of_item(&self, def_id: DefId) -> Option<DefId>;
     fn associated_item_cloned(&self, def: DefId) -> ty::AssociatedItem;
 
     // flags
     fn is_const_fn(&self, did: DefId) -> bool;
     fn is_default_impl(&self, impl_did: DefId) -> bool;
-    fn is_foreign_item(&self, did: DefId) -> bool;
     fn is_dllimport_foreign_item(&self, def: DefId) -> bool;
     fn is_statically_included_foreign_item(&self, def_id: DefId) -> bool;
-    fn is_exported_symbol(&self, def_id: DefId) -> bool;
 
     // crate metadata
     fn dylib_dependency_formats(&self, cnum: CrateNum)
@@ -337,28 +331,22 @@ impl CrateStore for DummyCrateStore {
     }
     fn item_generics_cloned(&self, def: DefId) -> ty::Generics
         { bug!("item_generics_cloned") }
-    fn item_attrs(&self, def_id: DefId) -> Rc<[ast::Attribute]> { bug!("item_attrs") }
-    fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name> { bug!("fn_arg_names") }
 
     // trait info
     fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId> { vec![] }
 
     // impl info
     fn impl_defaultness(&self, def: DefId) -> hir::Defaultness { bug!("impl_defaultness") }
-    fn impl_parent(&self, def: DefId) -> Option<DefId> { bug!("impl_parent") }
 
     // trait/impl-item info
-    fn trait_of_item(&self, def_id: DefId) -> Option<DefId> { bug!("trait_of_item") }
     fn associated_item_cloned(&self, def: DefId) -> ty::AssociatedItem
         { bug!("associated_item_cloned") }
 
     // flags
     fn is_const_fn(&self, did: DefId) -> bool { bug!("is_const_fn") }
     fn is_default_impl(&self, impl_did: DefId) -> bool { bug!("is_default_impl") }
-    fn is_foreign_item(&self, did: DefId) -> bool { bug!("is_foreign_item") }
     fn is_dllimport_foreign_item(&self, id: DefId) -> bool { false }
     fn is_statically_included_foreign_item(&self, def_id: DefId) -> bool { false }
-    fn is_exported_symbol(&self, def_id: DefId) -> bool { false }
 
     // crate metadata
     fn dylib_dependency_formats(&self, cnum: CrateNum)

src/librustc/middle/effect.rs

@@ -205,7 +205,7 @@ impl<'a, 'tcx> Visitor<'tcx> for EffectCheckVisitor<'a, 'tcx> {
                     } else if match self.tcx.hir.get_if_local(def_id) {
                         Some(hir::map::NodeForeignItem(..)) => true,
                         Some(..) => false,
-                        None => self.tcx.sess.cstore.is_foreign_item(def_id),
+                        None => self.tcx.is_foreign_item(def_id),
                     } {
                         self.require_unsafe_ext(expr.id, expr.span, "use of extern static", true);
                     }

src/librustc/ty/maps.rs

@@ -34,6 +34,7 @@ use std::ops::Deref;
 use std::rc::Rc;
 use syntax_pos::{Span, DUMMY_SP};
 use syntax::attr;
+use syntax::ast;
 use syntax::symbol::Symbol;
 
 pub trait Key: Clone + Hash + Eq + Debug {
@@ -340,6 +341,36 @@ impl<'tcx> QueryDescription for queries::deprecation<'tcx> {
     }
 }
 
+impl<'tcx> QueryDescription for queries::item_attrs<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        bug!("item_attrs")
+    }
+}
+
+impl<'tcx> QueryDescription for queries::is_exported_symbol<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        bug!("is_exported_symbol")
+    }
+}
+
+impl<'tcx> QueryDescription for queries::fn_arg_names<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        bug!("fn_arg_names")
+    }
+}
+
+impl<'tcx> QueryDescription for queries::impl_parent<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        bug!("impl_parent")
+    }
+}
+
+impl<'tcx> QueryDescription for queries::trait_of_item<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        bug!("trait_of_item")
+    }
+}
+
 impl<'tcx> QueryDescription for queries::item_body_nested_bodies<'tcx> {
     fn describe(tcx: TyCtxt, def_id: DefId) -> String {
         format!("nested item bodies of `{}`", tcx.item_path_str(def_id))
@@ -781,9 +812,14 @@ define_maps! { <'tcx>
     [] def_span: DefSpan(DefId) -> Span,
     [] stability: Stability(DefId) -> Option<attr::Stability>,
     [] deprecation: Deprecation(DefId) -> Option<attr::Deprecation>,
-    [] item_body_nested_bodies: metadata_dep_node(DefId) -> Rc<BTreeMap<hir::BodyId, hir::Body>>,
-    [] const_is_rvalue_promotable_to_static: metadata_dep_node(DefId) -> bool,
-    [] is_mir_available: metadata_dep_node(DefId) -> bool,
+    [] item_attrs: ItemAttrs(DefId) -> Rc<[ast::Attribute]>,
+    [] fn_arg_names: FnArgNames(DefId) -> Vec<ast::Name>,
+    [] impl_parent: ImplParent(DefId) -> Option<DefId>,
+    [] trait_of_item: TraitOfItem(DefId) -> Option<DefId>,
+    [] is_exported_symbol: IsExportedSymbol(DefId) -> bool,
+    [] item_body_nested_bodies: ItemBodyNestedBodies(DefId) -> Rc<BTreeMap<hir::BodyId, hir::Body>>,
+    [] const_is_rvalue_promotable_to_static: ConstIsRvaluePromotableToStatic(DefId) -> bool,
+    [] is_mir_available: IsMirAvailable(DefId) -> bool,
 }
 
 fn coherent_trait_dep_node((_, def_id): (CrateNum, DefId)) -> DepNode<DefId> {
@@ -798,10 +834,6 @@ fn reachability_dep_node(_: CrateNum) -> DepNode<DefId> {
     DepNode::Reachability
 }
 
-fn metadata_dep_node(def_id: DefId) -> DepNode<DefId> {
-    DepNode::MetaData(def_id)
-}
-
 fn mir_shim_dep_node(instance: ty::InstanceDef) -> DepNode<DefId> {
     instance.dep_node()
 }

src/librustc/ty/mod.rs

@@ -2360,7 +2360,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         if let Some(id) = self.hir.as_local_node_id(did) {
             Attributes::Borrowed(self.hir.attrs(id))
         } else {
-            Attributes::Owned(self.sess.cstore.item_attrs(did))
+            Attributes::Owned(self.item_attrs(did))
         }
     }
 
@@ -2396,7 +2396,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             let trait_ref = self.impl_trait_ref(impl_def_id).unwrap();
 
             // Record the trait->implementation mapping.
-            let parent = self.sess.cstore.impl_parent(impl_def_id).unwrap_or(trait_id);
+            let parent = self.impl_parent(impl_def_id).unwrap_or(trait_id);
             def.record_remote_impl(self, impl_def_id, trait_ref, parent);
         }
 
@@ -2433,22 +2433,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         }
     }
 
-    /// If the given def ID describes an item belonging to a trait,
-    /// return the ID of the trait that the trait item belongs to.
-    /// Otherwise, return `None`.
-    pub fn trait_of_item(self, def_id: DefId) -> Option<DefId> {
-        if def_id.krate != LOCAL_CRATE {
-            return self.sess.cstore.trait_of_item(def_id);
-        }
-        self.opt_associated_item(def_id)
-            .and_then(|associated_item| {
-                match associated_item.container {
-                    TraitContainer(def_id) => Some(def_id),
-                    ImplContainer(_) => None
-                }
-            })
-    }
-
     /// Construct a parameter environment suitable for static contexts or other contexts where there
     /// are no free type/lifetime parameters in scope.
     pub fn empty_parameter_environment(self) -> ParameterEnvironment<'tcx> {
@@ -2688,13 +2672,28 @@ fn def_span<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> Span {
     tcx.hir.span_if_local(def_id).unwrap()
 }
 
+/// If the given def ID describes an item belonging to a trait,
+/// return the ID of the trait that the trait item belongs to.
+/// Otherwise, return `None`.
+fn trait_of_item<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> Option<DefId> {
+    tcx.opt_associated_item(def_id)
+        .and_then(|associated_item| {
+            match associated_item.container {
+                TraitContainer(def_id) => Some(def_id),
+                ImplContainer(_) => None
+            }
+        })
+}
+
+
 pub fn provide(providers: &mut ty::maps::Providers) {
     *providers = ty::maps::Providers {
         associated_item,
         associated_item_def_ids,
         adt_sized_constraint,
         adt_dtorck_constraint,
         def_span,
+        trait_of_item,
         ..*providers
     };
 }

src/librustc_const_eval/eval.rs

@@ -74,7 +74,7 @@ pub fn lookup_const_by_id<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                 // constants, we only try to find the expression for a
                 // trait-associated const if the caller gives us the
                 // substitutions for the reference to it.
-                if tcx.sess.cstore.trait_of_item(def_id).is_some() {
+                if tcx.trait_of_item(def_id).is_some() {
                     resolve_trait_associated_const(tcx, def_id, substs)
                 } else {
                     Some((def_id, substs))

src/librustc_metadata/cstore_impl.rs

@@ -41,8 +41,6 @@ use rustc::hir::svh::Svh;
 use rustc_back::target::Target;
 use rustc::hir;
 
-use std::collections::BTreeMap;
-
 macro_rules! provide {
     (<$lt:tt> $tcx:ident, $def_id:ident, $cdata:ident $($name:ident => $compute:block)*) => {
         pub fn provide<$lt>(providers: &mut Providers<$lt>) {
@@ -113,21 +111,23 @@ provide! { <'tcx> tcx, def_id, cdata
     def_span => { cdata.get_span(def_id.index, &tcx.sess) }
     stability => { cdata.get_stability(def_id.index) }
     deprecation => { cdata.get_deprecation(def_id.index) }
-    item_body_nested_bodies => {
-        let map: BTreeMap<_, _> = cdata.entry(def_id.index).ast.into_iter().flat_map(|ast| {
-            ast.decode(cdata).nested_bodies.decode(cdata).map(|body| (body.id(), body))
-        }).collect();
-
-        Rc::new(map)
-    }
+    item_attrs => { cdata.get_item_attrs(def_id.index, &tcx.dep_graph) }
+    // FIXME(#38501) We've skipped a `read` on the `HirBody` of
+    // a `fn` when encoding, so the dep-tracking wouldn't work.
+    // This is only used by rustdoc anyway, which shouldn't have
+    // incremental recompilation ever enabled.
+    fn_arg_names => { cdata.get_fn_arg_names(def_id.index) }
+    impl_parent => { cdata.get_parent_impl(def_id.index) }
+    trait_of_item => { cdata.get_trait_of_item(def_id.index) }
+    is_exported_symbol => {
+        let dep_node = cdata.metadata_dep_node(GlobalMetaDataKind::ExportedSymbols);
+        cdata.exported_symbols.get(&tcx.dep_graph, dep_node).contains(&def_id.index)
+    }
+    item_body_nested_bodies => { Rc::new(cdata.item_body_nested_bodies(def_id.index)) }
     const_is_rvalue_promotable_to_static => {
-        cdata.entry(def_id.index).ast.expect("const item missing `ast`")
-            .decode(cdata).rvalue_promotable_to_static
-    }
-    is_mir_available => {
-        !cdata.is_proc_macro(def_id.index) &&
-        cdata.maybe_entry(def_id.index).and_then(|item| item.decode(cdata).mir).is_some()
+        cdata.const_is_rvalue_promotable_to_static(def_id.index)
     }
+    is_mir_available => { cdata.is_item_mir_available(def_id.index) }
 }
 
 impl CrateStore for cstore::CStore {
@@ -145,22 +145,6 @@ impl CrateStore for cstore::CStore {
         self.get_crate_data(def.krate).get_generics(def.index)
     }
 
-    fn item_attrs(&self, def_id: DefId) -> Rc<[ast::Attribute]>
-    {
-        self.get_crate_data(def_id.krate)
-            .get_item_attrs(def_id.index, &self.dep_graph)
-    }
-
-    fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name>
-    {
-        // FIXME(#38501) We've skipped a `read` on the `HirBody` of
-        // a `fn` when encoding, so the dep-tracking wouldn't work.
-        // This is only used by rustdoc anyway, which shouldn't have
-        // incremental recompilation ever enabled.
-        assert!(!self.dep_graph.is_fully_enabled());
-        self.get_crate_data(did.krate).get_fn_arg_names(did.index)
-    }
-
     fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId>
     {
         if let Some(def_id) = filter {
@@ -179,16 +163,6 @@ impl CrateStore for cstore::CStore {
         self.get_crate_data(def.krate).get_impl_defaultness(def.index)
     }
 
-    fn impl_parent(&self, impl_def: DefId) -> Option<DefId> {
-        self.dep_graph.read(DepNode::MetaData(impl_def));
-        self.get_crate_data(impl_def.krate).get_parent_impl(impl_def.index)
-    }
-
-    fn trait_of_item(&self, def_id: DefId) -> Option<DefId> {
-        self.dep_graph.read(DepNode::MetaData(def_id));
-        self.get_crate_data(def_id.krate).get_trait_of_item(def_id.index)
-    }
-
     fn associated_item_cloned(&self, def: DefId) -> ty::AssociatedItem
     {
         self.dep_graph.read(DepNode::MetaData(def));
@@ -206,23 +180,11 @@ impl CrateStore for cstore::CStore {
         self.get_crate_data(impl_did.krate).is_default_impl(impl_did.index)
     }
 
-    fn is_foreign_item(&self, did: DefId) -> bool {
-        self.get_crate_data(did.krate).is_foreign_item(did.index)
-    }
-
     fn is_statically_included_foreign_item(&self, def_id: DefId) -> bool
     {
         self.do_is_statically_included_foreign_item(def_id)
     }
 
-    fn is_exported_symbol(&self, def_id: DefId) -> bool {
-        let data = self.get_crate_data(def_id.krate);
-        let dep_node = data.metadata_dep_node(GlobalMetaDataKind::ExportedSymbols);
-        data.exported_symbols
-            .get(&self.dep_graph, dep_node)
-            .contains(&def_id.index)
-    }
-
     fn is_dllimport_foreign_item(&self, def_id: DefId) -> bool {
         if def_id.krate == LOCAL_CRATE {
             self.dllimport_foreign_items.borrow().contains(&def_id.index)