Auto merge of rust-lang#107644 - Zoxc:query-cache-tweak, r=cjgillot

Remove QueryStorage::store_nocache

This method was added in rust-lang#70674 but it doesn't seem to serve any purpose.

compiler/rustc_query_system/src/query/caches.rs

@@ -23,10 +23,6 @@ pub trait CacheSelector<'tcx, V> {
 pub trait QueryStorage {
     type Value: Debug;
     type Stored: Copy;
-
-    /// Store a value without putting it in the cache.
-    /// This is meant to be used with cycle errors.
-    fn store_nocache(&self, value: Self::Value) -> Self::Stored;
 }
 
 pub trait QueryCache: QueryStorage + Sized {
@@ -68,12 +64,6 @@ impl<K, V> Default for DefaultCache<K, V> {
 impl<K: Eq + Hash, V: Copy + Debug> QueryStorage for DefaultCache<K, V> {
     type Value = V;
     type Stored = V;
-
-    #[inline]
-    fn store_nocache(&self, value: Self::Value) -> Self::Stored {
-        // We have no dedicated storage
-        value
-    }
 }
 
 impl<K, V> QueryCache for DefaultCache<K, V>
@@ -144,13 +134,6 @@ impl<'tcx, K, V> Default for ArenaCache<'tcx, K, V> {
 impl<'tcx, K: Eq + Hash, V: Debug + 'tcx> QueryStorage for ArenaCache<'tcx, K, V> {
     type Value = V;
     type Stored = &'tcx V;
-
-    #[inline]
-    fn store_nocache(&self, value: Self::Value) -> Self::Stored {
-        let value = self.arena.alloc((value, DepNodeIndex::INVALID));
-        let value = unsafe { &*(&value.0 as *const _) };
-        &value
-    }
 }
 
 impl<'tcx, K, V: 'tcx> QueryCache for ArenaCache<'tcx, K, V>
@@ -231,12 +214,6 @@ impl<K: Idx, V> Default for VecCache<K, V> {
 impl<K: Eq + Idx, V: Copy + Debug> QueryStorage for VecCache<K, V> {
     type Value = V;
     type Stored = V;
-
-    #[inline]
-    fn store_nocache(&self, value: Self::Value) -> Self::Stored {
-        // We have no dedicated storage
-        value
-    }
 }
 
 impl<K, V> QueryCache for VecCache<K, V>
@@ -309,13 +286,6 @@ impl<'tcx, K: Idx, V> Default for VecArenaCache<'tcx, K, V> {
 impl<'tcx, K: Eq + Idx, V: Debug + 'tcx> QueryStorage for VecArenaCache<'tcx, K, V> {
     type Value = V;
     type Stored = &'tcx V;
-
-    #[inline]
-    fn store_nocache(&self, value: Self::Value) -> Self::Stored {
-        let value = self.arena.alloc((value, DepNodeIndex::INVALID));
-        let value = unsafe { &*(&value.0 as *const _) };
-        &value
-    }
 }
 
 impl<'tcx, K, V: 'tcx> QueryCache for VecArenaCache<'tcx, K, V>

compiler/rustc_query_system/src/query/plumbing.rs

@@ -121,20 +121,17 @@ where
 
 #[cold]
 #[inline(never)]
-fn mk_cycle<Qcx, V, R, D: DepKind>(
+fn mk_cycle<Qcx, R, D: DepKind>(
     qcx: Qcx,
     cycle_error: CycleError<D>,
     handler: HandleCycleError,
-    cache: &dyn crate::query::QueryStorage<Value = V, Stored = R>,
 ) -> R
 where
     Qcx: QueryContext + crate::query::HasDepContext<DepKind = D>,
-    V: std::fmt::Debug + Value<Qcx::DepContext, Qcx::DepKind>,
-    R: Copy,
+    R: std::fmt::Debug + Value<Qcx::DepContext, Qcx::DepKind>,
 {
     let error = report_cycle(qcx.dep_context().sess(), &cycle_error);
-    let value = handle_cycle_error(*qcx.dep_context(), &cycle_error, error, handler);
-    cache.store_nocache(value)
+    handle_cycle_error(*qcx.dep_context(), &cycle_error, error, handler)
 }
 
 fn handle_cycle_error<Tcx, V>(
@@ -397,7 +394,7 @@ where
             (result, Some(dep_node_index))
         }
         TryGetJob::Cycle(error) => {
-            let result = mk_cycle(qcx, error, Q::HANDLE_CYCLE_ERROR, cache);
+            let result = mk_cycle(qcx, error, Q::HANDLE_CYCLE_ERROR);
             (result, None)
         }
         #[cfg(parallel_compiler)]