Shrink the CrateStore dynamic interface.

compiler/rustc_interface/src/passes.rs

@@ -18,7 +18,7 @@ use rustc_metadata::creader::CStore;
 use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::DepGraph;
 use rustc_middle::middle;
-use rustc_middle::middle::cstore::{CrateStore, MetadataLoader, MetadataLoaderDyn};
+use rustc_middle::middle::cstore::{MetadataLoader, MetadataLoaderDyn};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, GlobalCtxt, ResolverOutputs, TyCtxt};
 use rustc_mir as mir;
@@ -860,11 +860,7 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
                     tcx.ensure().proc_macro_decls_static(())
                 });
 
-                let cstore = tcx
-                    .cstore_as_any()
-                    .downcast_ref::<CStore>()
-                    .expect("`tcx.cstore` is not a `CStore`");
-                cstore.report_unused_deps(tcx);
+                CStore::from_tcx(tcx).report_unused_deps(tcx);
             },
             {
                 par_iter(&tcx.hir().krate().modules).for_each(|(&module, _)| {

compiler/rustc_metadata/src/creader.rs

@@ -130,7 +130,7 @@ impl<'a> std::fmt::Debug for CrateDump<'a> {
 }
 
 impl CStore {
-    crate fn from_tcx(tcx: TyCtxt<'_>) -> &CStore {
+    pub fn from_tcx(tcx: TyCtxt<'_>) -> &CStore {
         tcx.cstore_as_any().downcast_ref::<CStore>().expect("`tcx.cstore` is not a `CStore`")
     }
 

compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs

@@ -5,7 +5,6 @@ use crate::rmeta::encoder;
 
 use rustc_ast as ast;
 use rustc_data_structures::stable_map::FxHashMap;
-use rustc_data_structures::svh::Svh;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind};
 use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, CRATE_DEF_INDEX, LOCAL_CRATE};
@@ -369,6 +368,7 @@ pub fn provide(providers: &mut Providers) {
             tcx.arena
                 .alloc_slice(&CStore::from_tcx(tcx).crate_dependencies_in_postorder(LOCAL_CRATE))
         },
+        crates: |tcx, ()| tcx.arena.alloc_slice(&CStore::from_tcx(tcx).crates_untracked()),
 
         ..*providers
     };
@@ -451,6 +451,16 @@ impl CStore {
         self.get_crate_data(def_id.krate).get_span(def_id.index, sess)
     }
 
+    pub fn def_kind(&self, def: DefId) -> DefKind {
+        self.get_crate_data(def.krate).def_kind(def.index)
+    }
+
+    pub fn crates_untracked(&self) -> Vec<CrateNum> {
+        let mut result = vec![];
+        self.iter_crate_data(|cnum, _| result.push(cnum));
+        result
+    }
+
     pub fn item_generics_num_lifetimes(&self, def_id: DefId, sess: &Session) -> usize {
         self.get_crate_data(def_id.krate).get_generics(def_id.index, sess).own_counts().lifetimes
     }
@@ -485,29 +495,21 @@ impl CrateStore for CStore {
         self
     }
 
-    fn crate_name_untracked(&self, cnum: CrateNum) -> Symbol {
+    fn crate_name(&self, cnum: CrateNum) -> Symbol {
         self.get_crate_data(cnum).root.name
     }
 
-    fn stable_crate_id_untracked(&self, cnum: CrateNum) -> StableCrateId {
+    fn stable_crate_id(&self, cnum: CrateNum) -> StableCrateId {
         self.get_crate_data(cnum).root.stable_crate_id
     }
 
-    fn crate_hash_untracked(&self, cnum: CrateNum) -> Svh {
-        self.get_crate_data(cnum).root.hash
-    }
-
     /// Returns the `DefKey` for a given `DefId`. This indicates the
     /// parent `DefId` as well as some idea of what kind of data the
     /// `DefId` refers to.
     fn def_key(&self, def: DefId) -> DefKey {
         self.get_crate_data(def.krate).def_key(def.index)
     }
 
-    fn def_kind(&self, def: DefId) -> DefKind {
-        self.get_crate_data(def.krate).def_kind(def.index)
-    }
-
     fn def_path(&self, def: DefId) -> DefPath {
         self.get_crate_data(def.krate).def_path(def.index)
     }
@@ -526,12 +528,6 @@ impl CrateStore for CStore {
         self.get_crate_data(cnum).def_path_hash_to_def_id(cnum, index_guess, hash)
     }
 
-    fn crates_untracked(&self) -> Vec<CrateNum> {
-        let mut result = vec![];
-        self.iter_crate_data(|cnum, _| result.push(cnum));
-        result
-    }
-
     fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata {
         encoder::encode_metadata(tcx)
     }

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1061,10 +1061,7 @@ impl EncodeContext<'a, 'tcx> {
             Lazy::empty()
         };
 
-        let data = ModData {
-            reexports,
-            expansion: tcx.resolutions(()).definitions.expansion_that_defined(local_def_id),
-        };
+        let data = ModData { reexports, expansion: tcx.expn_that_defined(local_def_id) };
 
         record!(self.tables.kind[def_id] <- EntryKind::Mod(self.lazy(data)));
         if self.is_proc_macro {

compiler/rustc_middle/src/hir/map/mod.rs

@@ -1,7 +1,6 @@
 use self::collector::NodeCollector;
 
 use crate::hir::{AttributeMap, IndexedHir};
-use crate::middle::cstore::CrateStore;
 use crate::ty::TyCtxt;
 use rustc_ast as ast;
 use rustc_data_structures::fingerprint::Fingerprint;
@@ -991,7 +990,7 @@ pub(super) fn crate_hash(tcx: TyCtxt<'_>, crate_num: CrateNum) -> Svh {
         },
     );
 
-    let upstream_crates = upstream_crates(&*tcx.untracked_resolutions.cstore);
+    let upstream_crates = upstream_crates(tcx);
 
     // We hash the final, remapped names of all local source files so we
     // don't have to include the path prefix remapping commandline args.
@@ -1021,13 +1020,13 @@ pub(super) fn crate_hash(tcx: TyCtxt<'_>, crate_num: CrateNum) -> Svh {
     Svh::new(crate_hash.to_smaller_hash())
 }
 
-fn upstream_crates(cstore: &dyn CrateStore) -> Vec<(StableCrateId, Svh)> {
-    let mut upstream_crates: Vec<_> = cstore
-        .crates_untracked()
+fn upstream_crates(tcx: TyCtxt<'_>) -> Vec<(StableCrateId, Svh)> {
+    let mut upstream_crates: Vec<_> = tcx
+        .crates(())
         .iter()
         .map(|&cnum| {
-            let stable_crate_id = cstore.stable_crate_id_untracked(cnum);
-            let hash = cstore.crate_hash_untracked(cnum);
+            let stable_crate_id = tcx.resolutions(()).cstore.stable_crate_id(cnum);
+            let hash = tcx.crate_hash(cnum);
             (stable_crate_id, hash)
         })
         .collect();

compiler/rustc_middle/src/middle/cstore.rs

@@ -5,9 +5,7 @@
 use crate::ty::TyCtxt;
 
 use rustc_ast as ast;
-use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::{self, MetadataRef};
-use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash};
 use rustc_macros::HashStable;
@@ -190,27 +188,26 @@ pub type MetadataLoaderDyn = dyn MetadataLoader + Sync;
 pub trait CrateStore: std::fmt::Debug {
     fn as_any(&self) -> &dyn Any;
 
-    // resolve
+    // Foreign definitions.
+    // This information is safe to access, since it's hashed as part of the DefPathHash, which incr.
+    // comp. uses to identify a DefId.
     fn def_key(&self, def: DefId) -> DefKey;
-    fn def_kind(&self, def: DefId) -> DefKind;
     fn def_path(&self, def: DefId) -> DefPath;
     fn def_path_hash(&self, def: DefId) -> DefPathHash;
+
+    // This information is safe to access, since it's hashed as part of the StableCrateId, which
+    // incr.  comp. uses to identify a CrateNum.
+    fn crate_name(&self, cnum: CrateNum) -> Symbol;
+    fn stable_crate_id(&self, cnum: CrateNum) -> StableCrateId;
+
+    /// Fetch a DefId from a DefPathHash for a foreign crate.
     fn def_path_hash_to_def_id(
         &self,
         cnum: CrateNum,
         index_guess: u32,
         hash: DefPathHash,
     ) -> Option<DefId>;
 
-    // "queries" used in resolve that aren't tracked for incremental compilation
-    fn crate_name_untracked(&self, cnum: CrateNum) -> Symbol;
-    fn stable_crate_id_untracked(&self, cnum: CrateNum) -> StableCrateId;
-    fn crate_hash_untracked(&self, cnum: CrateNum) -> Svh;
-
-    // This is basically a 1-based range of ints, which is a little
-    // silly - I may fix that.
-    fn crates_untracked(&self) -> Vec<CrateNum>;
-
     // utility functions
     fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata;
 }

compiler/rustc_middle/src/query/mod.rs

@@ -213,6 +213,8 @@ rustc_queries! {
     }
 
     query expn_that_defined(key: DefId) -> rustc_span::ExpnId {
+        // This query reads from untracked data in definitions.
+        eval_always
         desc { |tcx| "expansion that defined `{}`", tcx.def_path_str(key) }
     }
 
@@ -1446,6 +1448,7 @@ rustc_queries! {
         desc { "calculating the stability index for the local crate" }
     }
     query crates(_: ()) -> &'tcx [CrateNum] {
+        eval_always
         desc { "fetching all foreign CrateNum instances" }
     }
 

compiler/rustc_middle/src/ty/context.rs

@@ -1277,7 +1277,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if crate_num == LOCAL_CRATE {
             self.sess.local_stable_crate_id()
         } else {
-            self.untracked_resolutions.cstore.stable_crate_id_untracked(crate_num)
+            self.untracked_resolutions.cstore.stable_crate_id(crate_num)
         }
     }
 
@@ -1290,10 +1290,7 @@ impl<'tcx> TyCtxt<'tcx> {
             (self.crate_name, self.sess.local_stable_crate_id())
         } else {
             let cstore = &self.untracked_resolutions.cstore;
-            (
-                cstore.crate_name_untracked(def_id.krate),
-                cstore.stable_crate_id_untracked(def_id.krate),
-            )
+            (cstore.crate_name(def_id.krate), cstore.stable_crate_id(def_id.krate))
         };
 
         format!(
@@ -2831,8 +2828,6 @@ pub fn provide(providers: &mut ty::query::Providers) {
     };
     providers.extern_mod_stmt_cnum =
         |tcx, id| tcx.resolutions(()).extern_crate_map.get(&id).cloned();
-    providers.crates =
-        |tcx, ()| tcx.arena.alloc_slice(&tcx.resolutions(()).cstore.crates_untracked());
     providers.output_filenames = |tcx, ()| tcx.output_filenames.clone();
     providers.features_query = |tcx, ()| tcx.sess.features_untracked();
     providers.is_panic_runtime = |tcx, cnum| {

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -128,7 +128,7 @@ impl<'a> Resolver<'a> {
 
         let (name, parent) = if def_id.index == CRATE_DEF_INDEX {
             // This is the crate root
-            (self.cstore().crate_name_untracked(def_id.krate), None)
+            (self.cstore().crate_name(def_id.krate), None)
         } else {
             let def_key = self.cstore().def_key(def_id);
             let name = def_key