Shrink the size of ClosureTypeInfo to fit into 64 bytes again

compiler/rustc_middle/src/query/plumbing.rs

@@ -340,7 +340,8 @@ macro_rules! define_callbacks {
                     <$($K)* as keys::Key>::CacheSelector as CacheSelector<'tcx, Erase<$V>>
                 >::Cache;
 
-                // Ensure that keys grow no larger than 72 bytes
+                // Ensure that keys grow no larger than 72 bytes by accident.
+                // Increase this limit if necessary, but do try to keep the size low if possible
                 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
                 const _: () = {
                     if mem::size_of::<Key<'static>>() > 72 {
@@ -354,10 +355,11 @@ macro_rules! define_callbacks {
                     }
                 };
 
-                // Ensure that values grow no larger than 72 bytes
+                // Ensure that values grow no larger than 64 bytes by accident.
+                // Increase this limit if necessary, but do try to keep the size low if possible
                 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
                 const _: () = {
-                    if mem::size_of::<Value<'static>>() > 72 {
+                    if mem::size_of::<Value<'static>>() > 64 {
                         panic!("{}", concat!(
                             "the query `",
                             stringify!($name),

compiler/rustc_middle/src/ty/closure.rs

@@ -45,7 +45,7 @@ impl UpvarId {
 
 /// Information describing the capture of an upvar. This is computed
 /// during `typeck`, specifically by `regionck`.
-#[derive(PartialEq, Clone, Debug, Copy, TyEncodable, TyDecodable, HashStable)]
+#[derive(Eq, PartialEq, Clone, Debug, Copy, TyEncodable, TyDecodable, HashStable, Hash)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub enum UpvarCapture {
     /// Upvar is captured by value. This is always true when the
@@ -73,7 +73,7 @@ pub type RootVariableMinCaptureList<'tcx> = FxIndexMap<hir::HirId, MinCaptureLis
 pub type MinCaptureList<'tcx> = Vec<CapturedPlace<'tcx>>;
 
 /// A composite describing a `Place` that is captured by a closure.
-#[derive(PartialEq, Clone, Debug, TyEncodable, TyDecodable, HashStable)]
+#[derive(Eq, PartialEq, Clone, Debug, TyEncodable, TyDecodable, HashStable, Hash)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct CapturedPlace<'tcx> {
     /// Name and span where the binding happens.
@@ -192,7 +192,7 @@ impl<'tcx> CapturedPlace<'tcx> {
 #[derive(Copy, Clone, Debug, HashStable)]
 pub struct ClosureTypeInfo<'tcx> {
     user_provided_sig: ty::CanonicalPolyFnSig<'tcx>,
-    captures: &'tcx [&'tcx ty::CapturedPlace<'tcx>],
+    captures: &'tcx ty::List<&'tcx ty::CapturedPlace<'tcx>>,
     kind_origin: Option<&'tcx (Span, HirPlace<'tcx>)>,
 }
 
@@ -201,7 +201,7 @@ fn closure_typeinfo<'tcx>(tcx: TyCtxt<'tcx>, def: LocalDefId) -> ClosureTypeInfo
     let typeck_results = tcx.typeck(def);
     let user_provided_sig = typeck_results.user_provided_sigs[&def];
     let captures = typeck_results.closure_min_captures_flattened(def);
-    let captures = tcx.arena.alloc_from_iter(captures);
+    let captures = tcx.mk_captures_from_iter(captures);
     let hir_id = tcx.local_def_id_to_hir_id(def);
     let kind_origin = typeck_results.closure_kind_origins().get(hir_id);
     ClosureTypeInfo { user_provided_sig, captures, kind_origin }
@@ -253,7 +253,7 @@ pub fn is_ancestor_or_same_capture(
 /// Part of `MinCaptureInformationMap`; describes the capture kind (&, &mut, move)
 /// for a particular capture as well as identifying the part of the source code
 /// that triggered this capture to occur.
-#[derive(PartialEq, Clone, Debug, Copy, TyEncodable, TyDecodable, HashStable)]
+#[derive(Eq, PartialEq, Clone, Debug, Copy, TyEncodable, TyDecodable, HashStable, Hash)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct CaptureInfo {
     /// Expr Id pointing to use that resulted in selecting the current capture kind
@@ -332,7 +332,7 @@ pub fn place_to_string_for_capture<'tcx>(tcx: TyCtxt<'tcx>, place: &HirPlace<'tc
     curr_string
 }
 
-#[derive(Clone, PartialEq, Debug, TyEncodable, TyDecodable, Copy, HashStable)]
+#[derive(Eq, Clone, PartialEq, Debug, TyEncodable, TyDecodable, Copy, HashStable, Hash)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub enum BorrowKind {
     /// Data must be immutable and is aliasable.

compiler/rustc_middle/src/ty/context.rs

@@ -162,6 +162,7 @@ pub struct CtxtInterners<'tcx> {
     predefined_opaques_in_body: InternedSet<'tcx, PredefinedOpaquesData<'tcx>>,
     fields: InternedSet<'tcx, List<FieldIdx>>,
     local_def_ids: InternedSet<'tcx, List<LocalDefId>>,
+    captures: InternedSet<'tcx, List<&'tcx ty::CapturedPlace<'tcx>>>,
     offset_of: InternedSet<'tcx, List<(VariantIdx, FieldIdx)>>,
 }
 
@@ -189,6 +190,7 @@ impl<'tcx> CtxtInterners<'tcx> {
             predefined_opaques_in_body: Default::default(),
             fields: Default::default(),
             local_def_ids: Default::default(),
+            captures: Default::default(),
             offset_of: Default::default(),
         }
     }
@@ -1773,6 +1775,7 @@ slice_interners!(
     bound_variable_kinds: pub mk_bound_variable_kinds(ty::BoundVariableKind),
     fields: pub mk_fields(FieldIdx),
     local_def_ids: intern_local_def_ids(LocalDefId),
+    captures: intern_captures(&'tcx ty::CapturedPlace<'tcx>),
     offset_of: pub mk_offset_of((VariantIdx, FieldIdx)),
 );
 
@@ -2023,6 +2026,17 @@ impl<'tcx> TyCtxt<'tcx> {
         T::collect_and_apply(iter, |xs| self.mk_local_def_ids(xs))
     }
 
+    pub fn mk_captures_from_iter<I, T>(self, iter: I) -> T::Output
+    where
+        I: Iterator<Item = T>,
+        T: CollectAndApply<
+                &'tcx ty::CapturedPlace<'tcx>,
+                &'tcx List<&'tcx ty::CapturedPlace<'tcx>>,
+            >,
+    {
+        T::collect_and_apply(iter, |xs| self.intern_captures(xs))
+    }
+
     pub fn mk_const_list_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,