Abolish QueryVTable in favour of more assoc items on QueryConfig

compiler/rustc_query_impl/src/lib.rs

@@ -34,7 +34,6 @@ use rustc_query_system::query::*;
 pub use rustc_query_system::query::{deadlock, QueryContext};
 
 pub use rustc_query_system::query::QueryConfig;
-pub(crate) use rustc_query_system::query::QueryVTable;
 
 mod on_disk_cache;
 pub use on_disk_cache::OnDiskCache;

compiler/rustc_query_impl/src/plumbing.rs

@@ -493,28 +493,32 @@ macro_rules! define_queries {
                 &tcx.query_caches.$name
             }
 
+            fn execute_query(tcx: TyCtxt<'tcx>, key: Self::Key) -> Self::Stored {
+                tcx.$name(key)
+            }
+
             #[inline]
-            fn make_vtable(tcx: QueryCtxt<'tcx>, key: &Self::Key) ->
-                QueryVTable<QueryCtxt<'tcx>, Self::Key, Self::Value>
-            {
-                let compute = get_provider!([$($modifiers)*][tcx, $name, key]);
-                let cache_on_disk = Self::cache_on_disk(tcx.tcx, key);
-                QueryVTable {
-                    anon: is_anon!([$($modifiers)*]),
-                    eval_always: is_eval_always!([$($modifiers)*]),
-                    depth_limit: depth_limit!([$($modifiers)*]),
-                    feedable: feedable!([$($modifiers)*]),
-                    dep_kind: dep_graph::DepKind::$name,
-                    hash_result: hash_result!([$($modifiers)*]),
-                    handle_cycle_error: handle_cycle_error!([$($modifiers)*]),
-                    compute,
-                    try_load_from_disk: if cache_on_disk { should_ever_cache_on_disk!([$($modifiers)*]) } else { None },
-                }
+            // key is only sometimes used
+            #[allow(unused_variables)]
+            fn compute(qcx: QueryCtxt<'tcx>, key: &Self::Key) -> fn(TyCtxt<'tcx>, Self::Key) -> Self::Value {
+                get_provider!([$($modifiers)*][qcx, $name, key])
             }
 
-            fn execute_query(tcx: TyCtxt<'tcx>, k: Self::Key) -> Self::Stored {
-                tcx.$name(k)
+            #[inline]
+            fn try_load_from_disk(qcx: QueryCtxt<'tcx>, key: &Self::Key) -> rustc_query_system::query::TryLoadFromDisk<QueryCtxt<'tcx>, Self> {
+                let cache_on_disk = Self::cache_on_disk(qcx.tcx, key);
+                if cache_on_disk { should_ever_cache_on_disk!([$($modifiers)*]) } else { None }
             }
+
+            const ANON: bool = is_anon!([$($modifiers)*]);
+            const EVAL_ALWAYS: bool = is_eval_always!([$($modifiers)*]);
+            const DEPTH_LIMIT: bool = depth_limit!([$($modifiers)*]);
+            const FEEDABLE: bool = feedable!([$($modifiers)*]);
+
+            const DEP_KIND: rustc_middle::dep_graph::DepKind = dep_graph::DepKind::$name;
+            const HANDLE_CYCLE_ERROR: rustc_query_system::HandleCycleError = handle_cycle_error!([$($modifiers)*]);
+
+            const HASH_RESULT: rustc_query_system::query::HashResult<QueryCtxt<'tcx>, Self> = hash_result!([$($modifiers)*]);
         })*
 
         #[allow(nonstandard_style)]

compiler/rustc_query_system/src/query/config.rs

@@ -1,7 +1,6 @@
 //! Query configuration and description traits.
 
-use crate::dep_graph::DepNode;
-use crate::dep_graph::SerializedDepNodeIndex;
+use crate::dep_graph::{DepNode, DepNodeParams, SerializedDepNodeIndex};
 use crate::error::HandleCycleError;
 use crate::ich::StableHashingContext;
 use crate::query::caches::QueryCache;
@@ -11,10 +10,16 @@ use rustc_data_structures::fingerprint::Fingerprint;
 use std::fmt::Debug;
 use std::hash::Hash;
 
+pub type HashResult<Qcx, Q> =
+    Option<fn(&mut StableHashingContext<'_>, &<Q as QueryConfig<Qcx>>::Value) -> Fingerprint>;
+
+pub type TryLoadFromDisk<Qcx, Q> =
+    Option<fn(Qcx, SerializedDepNodeIndex) -> Option<<Q as QueryConfig<Qcx>>::Value>>;
+
 pub trait QueryConfig<Qcx: QueryContext> {
     const NAME: &'static str;
 
-    type Key: Eq + Hash + Clone + Debug;
+    type Key: DepNodeParams<Qcx::DepContext> + Eq + Hash + Clone + Debug;
     type Value: Debug;
     type Stored: Debug + Clone + std::borrow::Borrow<Self::Value>;
 
@@ -30,39 +35,27 @@ pub trait QueryConfig<Qcx: QueryContext> {
     where
         Qcx: 'a;
 
-    // Don't use this method to compute query results, instead use the methods on TyCtxt
-    fn make_vtable(tcx: Qcx, key: &Self::Key) -> QueryVTable<Qcx, Self::Key, Self::Value>;
-
     fn cache_on_disk(tcx: Qcx::DepContext, key: &Self::Key) -> bool;
 
     // Don't use this method to compute query results, instead use the methods on TyCtxt
     fn execute_query(tcx: Qcx::DepContext, k: Self::Key) -> Self::Stored;
-}
 
-#[derive(Copy, Clone)]
-pub struct QueryVTable<Qcx: QueryContext, K, V> {
-    pub anon: bool,
-    pub dep_kind: Qcx::DepKind,
-    pub eval_always: bool,
-    pub depth_limit: bool,
-    pub feedable: bool,
-
-    pub compute: fn(Qcx::DepContext, K) -> V,
-    pub hash_result: Option<fn(&mut StableHashingContext<'_>, &V) -> Fingerprint>,
-    pub handle_cycle_error: HandleCycleError,
-    // NOTE: this is also `None` if `cache_on_disk()` returns false, not just if it's unsupported by the query
-    pub try_load_from_disk: Option<fn(Qcx, SerializedDepNodeIndex) -> Option<V>>,
-}
+    fn compute(tcx: Qcx, key: &Self::Key) -> fn(Qcx::DepContext, Self::Key) -> Self::Value;
 
-impl<Qcx: QueryContext, K, V> QueryVTable<Qcx, K, V> {
-    pub(crate) fn to_dep_node(&self, tcx: Qcx::DepContext, key: &K) -> DepNode<Qcx::DepKind>
-    where
-        K: crate::dep_graph::DepNodeParams<Qcx::DepContext>,
-    {
-        DepNode::construct(tcx, self.dep_kind, key)
-    }
+    fn try_load_from_disk(qcx: Qcx, idx: &Self::Key) -> TryLoadFromDisk<Qcx, Self>;
+
+    const ANON: bool;
+    const EVAL_ALWAYS: bool;
+    const DEPTH_LIMIT: bool;
+    const FEEDABLE: bool;
+
+    const DEP_KIND: Qcx::DepKind;
+    const HANDLE_CYCLE_ERROR: HandleCycleError;
+
+    const HASH_RESULT: HashResult<Qcx, Self>;
 
-    pub(crate) fn compute(&self, tcx: Qcx::DepContext, key: K) -> V {
-        (self.compute)(tcx, key)
+    // Just here for convernience and checking that the key matches the kind, don't override this.
+    fn construct_dep_node(tcx: Qcx::DepContext, key: &Self::Key) -> DepNode<Qcx::DepKind> {
+        DepNode::construct(tcx, Self::DEP_KIND, key)
     }
 }

compiler/rustc_query_system/src/query/mod.rs

@@ -12,7 +12,7 @@ pub use self::caches::{
 };
 
 mod config;
-pub use self::config::{QueryConfig, QueryVTable};
+pub use self::config::{HashResult, QueryConfig, TryLoadFromDisk};
 
 use crate::dep_graph::DepKind;
 use crate::dep_graph::{DepNodeIndex, HasDepContext, SerializedDepNodeIndex};