Move def_path_hash_to_def_id to rustc_middle.

compiler/rustc_middle/src/dep_graph/dep_node.rs

@@ -338,11 +338,7 @@ impl DepNodeExt for DepNode {
     /// has been removed.
     fn extract_def_id(&self, tcx: TyCtxt<'tcx>) -> Option<DefId> {
         if self.kind.fingerprint_style() == FingerprintStyle::DefPathHash {
-            Some(
-                tcx.on_disk_cache
-                    .as_ref()?
-                    .def_path_hash_to_def_id(tcx, DefPathHash(self.hash.into())),
-            )
+            Some(tcx.def_path_hash_to_def_id(DefPathHash(self.hash.into())))
         } else {
             None
         }

compiler/rustc_middle/src/ty/context.rs

@@ -79,11 +79,6 @@ pub trait OnDiskCache<'tcx>: rustc_data_structures::sync::Sync {
     where
         Self: Sized;
 
-    /// Converts a `DefPathHash` to its corresponding `DefId` in the current compilation
-    /// session, if it still exists. This is used during incremental compilation to
-    /// turn a deserialized `DefPathHash` into its current `DefId`.
-    fn def_path_hash_to_def_id(&self, tcx: TyCtxt<'tcx>, def_path_hash: DefPathHash) -> DefId;
-
     fn drop_serialized_data(&self, tcx: TyCtxt<'tcx>);
 
     fn serialize(&self, tcx: TyCtxt<'tcx>, encoder: &mut FileEncoder) -> FileEncodeResult;
@@ -1301,6 +1296,27 @@ impl<'tcx> TyCtxt<'tcx> {
         }
     }
 
+    /// Converts a `DefPathHash` to its corresponding `DefId` in the current compilation
+    /// session, if it still exists. This is used during incremental compilation to
+    /// turn a deserialized `DefPathHash` into its current `DefId`.
+    pub fn def_path_hash_to_def_id(self, hash: DefPathHash) -> DefId {
+        debug!("def_path_hash_to_def_id({:?})", hash);
+
+        let stable_crate_id = hash.stable_crate_id();
+
+        // If this is a DefPathHash from the local crate, we can look up the
+        // DefId in the tcx's `Definitions`.
+        if stable_crate_id == self.sess.local_stable_crate_id() {
+            self.untracked_resolutions.definitions.local_def_path_hash_to_def_id(hash).to_def_id()
+        } else {
+            // If this is a DefPathHash from an upstream crate, let the CrateStore map
+            // it to a DefId.
+            let cstore = &self.untracked_resolutions.cstore;
+            let cnum = cstore.stable_crate_id_to_crate_num(stable_crate_id);
+            cstore.def_path_hash_to_def_id(cnum, hash)
+        }
+    }
+
     pub fn def_path_debug_str(self, def_id: DefId) -> String {
         // We are explicitly not going through queries here in order to get
         // crate name and stable crate id since this code is called from debug!()

compiler/rustc_query_impl/src/on_disk_cache.rs

@@ -358,23 +358,6 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
             Ok(())
         })
     }
-
-    fn def_path_hash_to_def_id(&self, tcx: TyCtxt<'tcx>, hash: DefPathHash) -> DefId {
-        debug!("def_path_hash_to_def_id({:?})", hash);
-
-        let stable_crate_id = hash.stable_crate_id();
-
-        // If this is a DefPathHash from the local crate, we can look up the
-        // DefId in the tcx's `Definitions`.
-        if stable_crate_id == tcx.sess.local_stable_crate_id() {
-            tcx.definitions_untracked().local_def_path_hash_to_def_id(hash).to_def_id()
-        } else {
-            // If this is a DefPathHash from an upstream crate, let the CrateStore map
-            // it to a DefId.
-            let cnum = tcx.cstore_untracked().stable_crate_id_to_crate_num(stable_crate_id);
-            tcx.cstore_untracked().def_path_hash_to_def_id(cnum, hash)
-        }
-    }
 }
 
 impl<'sess> OnDiskCache<'sess> {
@@ -764,7 +747,7 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefId {
         // If we get to this point, then all of the query inputs were green,
         // which means that the definition with this hash is guaranteed to
         // still exist in the current compilation session.
-        Ok(d.tcx().on_disk_cache.as_ref().unwrap().def_path_hash_to_def_id(d.tcx(), def_path_hash))
+        Ok(d.tcx().def_path_hash_to_def_id(def_path_hash))
     }
 }