Hash less while hashing def-ids.

Author: cjgillot

compiler/rustc_span/src/def_id.rs

@@ -110,6 +110,7 @@ impl DefPathHash {
 
     /// Builds a new [DefPathHash] with the given [StableCrateId] and
     /// `local_hash`, where `local_hash` must be unique within its crate.
+    #[inline]
     pub fn new(stable_crate_id: StableCrateId, local_hash: Hash64) -> DefPathHash {
         DefPathHash(Fingerprint::new(stable_crate_id.0, local_hash))
     }
@@ -404,21 +405,21 @@ rustc_data_structures::define_id_collections!(
 impl<CTX: HashStableContext> HashStable<CTX> for DefId {
     #[inline]
     fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
-        self.to_stable_hash_key(hcx).hash_stable(hcx, hasher);
+        hcx.def_path_hash(*self).hash_stable(hcx, hasher);
     }
 }
 
 impl<CTX: HashStableContext> HashStable<CTX> for LocalDefId {
     #[inline]
     fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
-        self.to_stable_hash_key(hcx).hash_stable(hcx, hasher);
+        hcx.def_path_hash(self.to_def_id()).local_hash().hash_stable(hcx, hasher);
     }
 }
 
 impl<CTX: HashStableContext> HashStable<CTX> for CrateNum {
     #[inline]
     fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
-        self.to_stable_hash_key(hcx).hash_stable(hcx, hasher);
+        self.as_def_id().to_stable_hash_key(hcx).stable_crate_id().hash_stable(hcx, hasher);
     }
 }