Retire hir::*ItemRef.

Author: cjgillot

compiler/rustc_ast_lowering/src/index.rs

@@ -381,20 +381,12 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
         })
     }
 
-    fn visit_trait_item_ref(&mut self, ii: &'hir TraitItemRef) {
-        // Do not visit the duplicate information in TraitItemRef. We want to
-        // map the actual nodes, not the duplicate ones in the *Ref.
-        let TraitItemRef { id, ident: _, span: _ } = *ii;
-
-        self.visit_nested_trait_item(id);
+    fn visit_trait_item_ref(&mut self, id: &'hir TraitItemId) {
+        self.visit_nested_trait_item(*id);
     }
 
-    fn visit_impl_item_ref(&mut self, ii: &'hir ImplItemRef) {
-        // Do not visit the duplicate information in ImplItemRef. We want to
-        // map the actual nodes, not the duplicate ones in the *Ref.
-        let ImplItemRef { id, ident: _, span: _ } = *ii;
-
-        self.visit_nested_impl_item(id);
+    fn visit_impl_item_ref(&mut self, id: &'hir ImplItemId) {
+        self.visit_nested_impl_item(*id);
     }
 
     fn visit_foreign_item_ref(&mut self, id: &'hir ForeignItemId) {

compiler/rustc_ast_lowering/src/item.rs

@@ -963,13 +963,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
         self.arena.alloc(item)
     }
 
-    fn lower_trait_item_ref(&mut self, i: &AssocItem) -> hir::TraitItemRef {
-        let id = hir::TraitItemId { owner_id: self.owner_id(i.id) };
-        hir::TraitItemRef {
-            id,
-            ident: self.lower_ident(i.kind.ident().unwrap()),
-            span: self.lower_span(i.span),
-        }
+    fn lower_trait_item_ref(&mut self, i: &AssocItem) -> hir::TraitItemId {
+        hir::TraitItemId { owner_id: self.owner_id(i.id) }
     }
 
     /// Construct `ExprKind::Err` for the given `span`.
@@ -1109,14 +1104,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
         self.arena.alloc(item)
     }
 
-    fn lower_impl_item_ref(&mut self, i: &AssocItem) -> hir::ImplItemRef {
-        hir::ImplItemRef {
-            id: hir::ImplItemId { owner_id: self.owner_id(i.id) },
-            // `unwrap` is safe because `AssocItemKind::{MacCall,DelegationMac}` are the only
-            // assoc item kinds without an identifier and they cannot reach here.
-            ident: self.lower_ident(i.kind.ident().unwrap()),
-            span: self.lower_span(i.span),
-        }
+    fn lower_impl_item_ref(&mut self, i: &AssocItem) -> hir::ImplItemId {
+        hir::ImplItemId { owner_id: self.owner_id(i.id) }
     }
 
     fn lower_defaultness(

compiler/rustc_hir/src/hir.rs

@@ -4161,7 +4161,7 @@ impl<'hir> Item<'hir> {
                 Ident,
                 &'hir Generics<'hir>,
                 GenericBounds<'hir>,
-                &'hir [TraitItemRef]
+                &'hir [TraitItemId]
             ),
             ItemKind::Trait(is_auto, safety, ident, generics, bounds, items),
             (*is_auto, *safety, *ident, generics, bounds, items);
@@ -4334,7 +4334,7 @@ pub enum ItemKind<'hir> {
     /// A union definition, e.g., `union Foo<A, B> {x: A, y: B}`.
     Union(Ident, &'hir Generics<'hir>, VariantData<'hir>),
     /// A trait definition.
-    Trait(IsAuto, Safety, Ident, &'hir Generics<'hir>, GenericBounds<'hir>, &'hir [TraitItemRef]),
+    Trait(IsAuto, Safety, Ident, &'hir Generics<'hir>, GenericBounds<'hir>, &'hir [TraitItemId]),
     /// A trait alias.
     TraitAlias(Ident, &'hir Generics<'hir>, GenericBounds<'hir>),
 
@@ -4361,7 +4361,7 @@ pub struct Impl<'hir> {
     pub of_trait: Option<TraitRef<'hir>>,
 
     pub self_ty: &'hir Ty<'hir>,
-    pub items: &'hir [ImplItemRef],
+    pub items: &'hir [ImplItemId],
 }
 
 impl ItemKind<'_> {
@@ -4404,32 +4404,6 @@ impl ItemKind<'_> {
     }
 }
 
-/// A reference from an trait to one of its associated items. This
-/// contains the item's id, naturally, but also the item's name and
-/// some other high-level details (like whether it is an associated
-/// type or method, and whether it is public). This allows other
-/// passes to find the impl they want without loading the ID (which
-/// means fewer edges in the incremental compilation graph).
-#[derive(Debug, Clone, Copy, HashStable_Generic)]
-pub struct TraitItemRef {
-    pub id: TraitItemId,
-    pub ident: Ident,
-    pub span: Span,
-}
-
-/// A reference from an impl to one of its associated items. This
-/// contains the item's ID, naturally, but also the item's name and
-/// some other high-level details (like whether it is an associated
-/// type or method, and whether it is public). This allows other
-/// passes to find the impl they want without loading the ID (which
-/// means fewer edges in the incremental compilation graph).
-#[derive(Debug, Clone, Copy, HashStable_Generic)]
-pub struct ImplItemRef {
-    pub id: ImplItemId,
-    pub ident: Ident,
-    pub span: Span,
-}
-
 // The bodies for items are stored "out of line", in a separate
 // hashmap in the `Crate`. Here we just record the hir-id of the item
 // so it can fetched later.

compiler/rustc_hir/src/intravisit.rs

@@ -435,17 +435,17 @@ pub trait Visitor<'v>: Sized {
     fn visit_trait_item(&mut self, ti: &'v TraitItem<'v>) -> Self::Result {
         walk_trait_item(self, ti)
     }
-    fn visit_trait_item_ref(&mut self, ii: &'v TraitItemRef) -> Self::Result {
-        walk_trait_item_ref(self, ii)
+    fn visit_trait_item_ref(&mut self, ii: &'v TraitItemId) -> Self::Result {
+        walk_trait_item_ref(self, *ii)
     }
     fn visit_impl_item(&mut self, ii: &'v ImplItem<'v>) -> Self::Result {
         walk_impl_item(self, ii)
     }
     fn visit_foreign_item_ref(&mut self, ii: &'v ForeignItemId) -> Self::Result {
         walk_foreign_item_ref(self, *ii)
     }
-    fn visit_impl_item_ref(&mut self, ii: &'v ImplItemRef) -> Self::Result {
-        walk_impl_item_ref(self, ii)
+    fn visit_impl_item_ref(&mut self, ii: &'v ImplItemId) -> Self::Result {
+        walk_impl_item_ref(self, *ii)
     }
     fn visit_trait_ref(&mut self, t: &'v TraitRef<'v>) -> Self::Result {
         walk_trait_ref(self, t)
@@ -1245,13 +1245,8 @@ pub fn walk_trait_item<'v, V: Visitor<'v>>(
     V::Result::output()
 }
 
-pub fn walk_trait_item_ref<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    trait_item_ref: &'v TraitItemRef,
-) -> V::Result {
-    let TraitItemRef { id, ident, span: _ } = *trait_item_ref;
-    try_visit!(visitor.visit_nested_trait_item(id));
-    visitor.visit_ident(ident)
+pub fn walk_trait_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, id: TraitItemId) -> V::Result {
+    visitor.visit_nested_trait_item(id)
 }
 
 pub fn walk_impl_item<'v, V: Visitor<'v>>(
@@ -1294,13 +1289,8 @@ pub fn walk_foreign_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, id: ForeignIte
     visitor.visit_nested_foreign_item(id)
 }
 
-pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    impl_item_ref: &'v ImplItemRef,
-) -> V::Result {
-    let ImplItemRef { id, ident, span: _ } = *impl_item_ref;
-    try_visit!(visitor.visit_nested_impl_item(id));
-    visitor.visit_ident(ident)
+pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, id: ImplItemId) -> V::Result {
+    visitor.visit_nested_impl_item(id)
 }
 
 pub fn walk_trait_ref<'v, V: Visitor<'v>>(

compiler/rustc_hir_analysis/src/collect.rs

@@ -847,11 +847,9 @@ fn adt_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AdtDef<'_> {
 fn trait_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::TraitDef {
     let item = tcx.hir_expect_item(def_id);
 
-    let (is_alias, is_auto, safety, items) = match item.kind {
-        hir::ItemKind::Trait(is_auto, safety, .., items) => {
-            (false, is_auto == hir::IsAuto::Yes, safety, items)
-        }
-        hir::ItemKind::TraitAlias(..) => (true, false, hir::Safety::Safe, &[][..]),
+    let (is_alias, is_auto, safety) = match item.kind {
+        hir::ItemKind::Trait(is_auto, safety, ..) => (false, is_auto == hir::IsAuto::Yes, safety),
+        hir::ItemKind::TraitAlias(..) => (true, false, hir::Safety::Safe),
         _ => span_bug!(item.span, "trait_def_of_item invoked on non-trait"),
     };
 
@@ -912,13 +910,16 @@ fn trait_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::TraitDef {
         // functions in the trait with default implementations
         .and_then(|(list, attr_span)| {
             let errors = list.iter().filter_map(|ident| {
-                let item = items.iter().find(|item| item.ident == *ident);
+                let item = tcx
+                    .associated_items(def_id)
+                    .filter_by_name_unhygienic(ident.name)
+                    .find(|item| item.ident(tcx) == *ident);
 
                 match item {
-                    Some(item) if matches!(tcx.def_kind(item.id.owner_id), DefKind::AssocFn) => {
-                        if !tcx.defaultness(item.id.owner_id).has_value() {
+                    Some(item) if matches!(item.kind, ty::AssocKind::Fn { .. }) => {
+                        if !item.defaultness(tcx).has_value() {
                             tcx.dcx().emit_err(errors::FunctionNotHaveDefaultImplementation {
-                                span: item.span,
+                                span: tcx.def_span(item.def_id),
                                 note_span: attr_span,
                             });
 
@@ -929,7 +930,7 @@ fn trait_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::TraitDef {
                     }
                     Some(item) => {
                         tcx.dcx().emit_err(errors::MustImplementNotFunction {
-                            span: item.span,
+                            span: tcx.def_span(item.def_id),
                             span_note: errors::MustImplementNotFunctionSpanNote { span: attr_span },
                             note: errors::MustImplementNotFunctionNote {},
                         });

compiler/rustc_hir_pretty/src/lib.rs

@@ -730,8 +730,8 @@ impl<'a> State<'a> {
 
                 self.space();
                 self.bopen(ib);
-                for impl_item in items {
-                    self.ann.nested(self, Nested::ImplItem(impl_item.id));
+                for &impl_item in items {
+                    self.ann.nested(self, Nested::ImplItem(impl_item));
                 }
                 self.bclose(item.span, cb);
             }
@@ -746,8 +746,8 @@ impl<'a> State<'a> {
                 self.print_where_clause(generics);
                 self.word(" ");
                 self.bopen(ib);
-                for trait_item in trait_items {
-                    self.ann.nested(self, Nested::TraitItem(trait_item.id));
+                for &trait_item in trait_items {
+                    self.ann.nested(self, Nested::TraitItem(trait_item));
                 }
                 self.bclose(item.span, cb);
             }

compiler/rustc_lint/src/deref_into_dyn_supertrait.rs

@@ -1,7 +1,7 @@
 use rustc_hir::{self as hir, LangItem};
 use rustc_middle::ty;
 use rustc_session::{declare_lint, declare_lint_pass};
-use rustc_span::sym;
+use rustc_span::{Ident, sym};
 use rustc_trait_selection::traits::supertraits;
 
 use crate::lints::{SupertraitAsDerefTarget, SupertraitAsDerefTargetLabel};
@@ -79,11 +79,15 @@ impl<'tcx> LateLintPass<'tcx> for DerefIntoDynSupertrait {
             // erase regions in self type for better diagnostic presentation
             let (self_ty, target_principal, supertrait_principal) =
                 tcx.erase_regions((self_ty, target_principal, supertrait_principal));
-            let label2 = impl_
-                .items
-                .iter()
-                .find_map(|i| (i.ident.name == sym::Target).then_some(i.span))
-                .map(|label| SupertraitAsDerefTargetLabel { label });
+            let label2 = tcx
+                .associated_items(item.owner_id)
+                .find_by_ident_and_kind(
+                    tcx,
+                    Ident::with_dummy_span(sym::Target),
+                    ty::AssocTag::Type,
+                    item.owner_id.to_def_id(),
+                )
+                .map(|label| SupertraitAsDerefTargetLabel { label: tcx.def_span(label.def_id) });
             let span = tcx.def_span(item.owner_id.def_id);
             cx.emit_span_lint(
                 DEREF_INTO_DYN_SUPERTRAIT,

compiler/rustc_passes/src/check_attr.rs

@@ -1096,7 +1096,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             ItemKind::Trait(_, _, _, generics, _, items)
                 if generics.params.len() != 0
                     || items.iter().any(|item| {
-                        matches!(self.tcx.def_kind(item.id.owner_id), DefKind::AssocTy)
+                        matches!(self.tcx.def_kind(item.owner_id), DefKind::AssocTy)
                     }) => {}
             ItemKind::TyAlias(_, generics, _) if generics.params.len() != 0 => {}
             _ => {

compiler/rustc_passes/src/dead.rs

@@ -415,8 +415,8 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
                 hir::ItemKind::Trait(.., trait_item_refs) => {
                     // mark assoc ty live if the trait is live
                     for trait_item in trait_item_refs {
-                        if matches!(self.tcx.def_kind(trait_item.id.owner_id), DefKind::AssocTy) {
-                            self.check_def_id(trait_item.id.owner_id.to_def_id());
+                        if matches!(self.tcx.def_kind(trait_item.owner_id), DefKind::AssocTy) {
+                            self.check_def_id(trait_item.owner_id.to_def_id());
                         }
                     }
                     intravisit::walk_item(self, item)

compiler/rustc_passes/src/input_stats.rs

@@ -467,9 +467,9 @@ impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
         hir_visit::walk_trait_item(self, ti)
     }
 
-    fn visit_trait_item_ref(&mut self, ti: &'v hir::TraitItemRef) {
-        self.record("TraitItemRef", Some(ti.id.hir_id()), ti);
-        hir_visit::walk_trait_item_ref(self, ti)
+    fn visit_trait_item_ref(&mut self, ti: &'v hir::TraitItemId) {
+        self.record("TraitItemId", Some(ti.hir_id()), ti);
+        hir_visit::walk_trait_item_ref(self, *ti)
     }
 
     fn visit_impl_item(&mut self, ii: &'v hir::ImplItem<'v>) {
@@ -485,9 +485,9 @@ impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
         hir_visit::walk_foreign_item_ref(self, *fi)
     }
 
-    fn visit_impl_item_ref(&mut self, ii: &'v hir::ImplItemRef) {
-        self.record("ImplItemRef", Some(ii.id.hir_id()), ii);
-        hir_visit::walk_impl_item_ref(self, ii)
+    fn visit_impl_item_ref(&mut self, ii: &'v hir::ImplItemId) {
+        self.record("ImplItemId", Some(ii.hir_id()), ii);
+        hir_visit::walk_impl_item_ref(self, *ii)
     }
 
     fn visit_param_bound(&mut self, b: &'v hir::GenericBound<'v>) {