Rollup merge of #93853 - steffahn:map_by_value, r=wesleywiser

Make all `hir::Map` methods consistently by-value

`hir::Map` only consists of a single reference (as part of the contained `TyCtxt`) anyways, so copying is literally zero overhead compared to passing a reference

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -763,7 +763,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             HirId, ImplItem, ImplItemKind, Item, ItemKind,
         };
 
-        fn maybe_body_id_of_fn(hir_map: &Map<'_>, id: HirId) -> Option<BodyId> {
+        fn maybe_body_id_of_fn(hir_map: Map<'_>, id: HirId) -> Option<BodyId> {
             match hir_map.find(id) {
                 Some(Node::Item(Item { kind: ItemKind::Fn(_, _, body_id), .. }))
                 | Some(Node::ImplItem(ImplItem { kind: ImplItemKind::Fn(_, body_id), .. })) => {
@@ -774,7 +774,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         }
         let hir_map = self.infcx.tcx.hir();
         let mir_body_hir_id = self.mir_hir_id();
-        if let Some(fn_body_id) = maybe_body_id_of_fn(&hir_map, mir_body_hir_id) {
+        if let Some(fn_body_id) = maybe_body_id_of_fn(hir_map, mir_body_hir_id) {
             if let Block(
                 hir::Block {
                     expr:

compiler/rustc_hir/src/intravisit.rs

@@ -141,22 +141,22 @@ pub trait Map<'hir> {
 // Used when no map is actually available, forcing manual implementation of nested visitors.
 impl<'hir> Map<'hir> for ! {
     fn find(&self, _: HirId) -> Option<Node<'hir>> {
-        unreachable!()
+        *self;
     }
     fn body(&self, _: BodyId) -> &'hir Body<'hir> {
-        unreachable!()
+        *self;
     }
     fn item(&self, _: ItemId) -> &'hir Item<'hir> {
-        unreachable!()
+        *self;
     }
     fn trait_item(&self, _: TraitItemId) -> &'hir TraitItem<'hir> {
-        unreachable!()
+        *self;
     }
     fn impl_item(&self, _: ImplItemId) -> &'hir ImplItem<'hir> {
-        unreachable!()
+        *self;
     }
     fn foreign_item(&self, _: ForeignItemId) -> &'hir ForeignItem<'hir> {
-        unreachable!()
+        *self;
     }
 }
 

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -2226,7 +2226,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         bound_kind: GenericKind<'tcx>,
         sub: Region<'tcx>,
     ) -> DiagnosticBuilder<'a> {
-        let hir = &self.tcx.hir();
+        let hir = self.tcx.hir();
         // Attempt to obtain the span of the parameter so we can
         // suggest adding an explicit lifetime bound to it.
         let generics = self

compiler/rustc_middle/src/hir/map/mod.rs

@@ -149,18 +149,18 @@ impl<'hir> Iterator for ParentOwnerIterator<'hir> {
 }
 
 impl<'hir> Map<'hir> {
-    pub fn krate(&self) -> &'hir Crate<'hir> {
+    pub fn krate(self) -> &'hir Crate<'hir> {
         self.tcx.hir_crate(())
     }
 
-    pub fn root_module(&self) -> &'hir Mod<'hir> {
+    pub fn root_module(self) -> &'hir Mod<'hir> {
         match self.tcx.hir_owner(CRATE_DEF_ID).map(|o| o.node) {
             Some(OwnerNode::Crate(item)) => item,
             _ => bug!(),
         }
     }
 
-    pub fn items(&self) -> impl Iterator<Item = &'hir Item<'hir>> + 'hir {
+    pub fn items(self) -> impl Iterator<Item = &'hir Item<'hir>> + 'hir {
         let krate = self.krate();
         krate.owners.iter().filter_map(|owner| match owner.as_owner()?.node() {
             OwnerNode::Item(item) => Some(item),
@@ -168,16 +168,16 @@ impl<'hir> Map<'hir> {
         })
     }
 
-    pub fn def_key(&self, def_id: LocalDefId) -> DefKey {
+    pub fn def_key(self, def_id: LocalDefId) -> DefKey {
         // Accessing the DefKey is ok, since it is part of DefPathHash.
         self.tcx.untracked_resolutions.definitions.def_key(def_id)
     }
 
-    pub fn def_path_from_hir_id(&self, id: HirId) -> Option<DefPath> {
+    pub fn def_path_from_hir_id(self, id: HirId) -> Option<DefPath> {
         self.opt_local_def_id(id).map(|def_id| self.def_path(def_id))
     }
 
-    pub fn def_path(&self, def_id: LocalDefId) -> DefPath {
+    pub fn def_path(self, def_id: LocalDefId) -> DefPath {
         // Accessing the DefPath is ok, since it is part of DefPathHash.
         self.tcx.untracked_resolutions.definitions.def_path(def_id)
     }
@@ -189,7 +189,7 @@ impl<'hir> Map<'hir> {
     }
 
     #[inline]
-    pub fn local_def_id(&self, hir_id: HirId) -> LocalDefId {
+    pub fn local_def_id(self, hir_id: HirId) -> LocalDefId {
         self.opt_local_def_id(hir_id).unwrap_or_else(|| {
             bug!(
                 "local_def_id: no entry for `{:?}`, which has a map of `{:?}`",
@@ -200,7 +200,7 @@ impl<'hir> Map<'hir> {
     }
 
     #[inline]
-    pub fn opt_local_def_id(&self, hir_id: HirId) -> Option<LocalDefId> {
+    pub fn opt_local_def_id(self, hir_id: HirId) -> Option<LocalDefId> {
         if hir_id.local_id == ItemLocalId::new(0) {
             Some(hir_id.owner)
         } else {
@@ -214,18 +214,18 @@ impl<'hir> Map<'hir> {
     }
 
     #[inline]
-    pub fn local_def_id_to_hir_id(&self, def_id: LocalDefId) -> HirId {
+    pub fn local_def_id_to_hir_id(self, def_id: LocalDefId) -> HirId {
         self.tcx.local_def_id_to_hir_id(def_id)
     }
 
-    pub fn iter_local_def_id(&self) -> impl Iterator<Item = LocalDefId> + '_ {
+    pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> + 'hir {
         // Create a dependency to the crate to be sure we reexcute this when the amount of
         // definitions change.
         self.tcx.ensure().hir_crate(());
         self.tcx.untracked_resolutions.definitions.iter_local_def_id()
     }
 
-    pub fn opt_def_kind(&self, local_def_id: LocalDefId) -> Option<DefKind> {
+    pub fn opt_def_kind(self, local_def_id: LocalDefId) -> Option<DefKind> {
         let hir_id = self.local_def_id_to_hir_id(local_def_id);
         let def_kind = match self.find(hir_id)? {
             Node::Item(item) => match item.kind {
@@ -312,12 +312,12 @@ impl<'hir> Map<'hir> {
         Some(def_kind)
     }
 
-    pub fn def_kind(&self, local_def_id: LocalDefId) -> DefKind {
+    pub fn def_kind(self, local_def_id: LocalDefId) -> DefKind {
         self.opt_def_kind(local_def_id)
             .unwrap_or_else(|| bug!("def_kind: unsupported node: {:?}", local_def_id))
     }
 
-    pub fn find_parent_node(&self, id: HirId) -> Option<HirId> {
+    pub fn find_parent_node(self, id: HirId) -> Option<HirId> {
         if id.local_id == ItemLocalId::from_u32(0) {
             Some(self.tcx.hir_owner_parent(id.owner))
         } else {
@@ -328,12 +328,12 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn get_parent_node(&self, hir_id: HirId) -> HirId {
+    pub fn get_parent_node(self, hir_id: HirId) -> HirId {
         self.find_parent_node(hir_id).unwrap()
     }
 
     /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found.
-    pub fn find(&self, id: HirId) -> Option<Node<'hir>> {
+    pub fn find(self, id: HirId) -> Option<Node<'hir>> {
         if id.local_id == ItemLocalId::from_u32(0) {
             let owner = self.tcx.hir_owner(id.owner)?;
             Some(owner.node.into())
@@ -346,26 +346,26 @@ impl<'hir> Map<'hir> {
 
     /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found.
     #[inline]
-    pub fn find_by_def_id(&self, id: LocalDefId) -> Option<Node<'hir>> {
+    pub fn find_by_def_id(self, id: LocalDefId) -> Option<Node<'hir>> {
         self.find(self.local_def_id_to_hir_id(id))
     }
 
     /// Retrieves the `Node` corresponding to `id`, panicking if it cannot be found.
-    pub fn get(&self, id: HirId) -> Node<'hir> {
+    pub fn get(self, id: HirId) -> Node<'hir> {
         self.find(id).unwrap_or_else(|| bug!("couldn't find hir id {} in the HIR map", id))
     }
 
     /// Retrieves the `Node` corresponding to `id`, panicking if it cannot be found.
     #[inline]
-    pub fn get_by_def_id(&self, id: LocalDefId) -> Node<'hir> {
+    pub fn get_by_def_id(self, id: LocalDefId) -> Node<'hir> {
         self.find_by_def_id(id).unwrap_or_else(|| bug!("couldn't find {:?} in the HIR map", id))
     }
 
-    pub fn get_if_local(&self, id: DefId) -> Option<Node<'hir>> {
+    pub fn get_if_local(self, id: DefId) -> Option<Node<'hir>> {
         id.as_local().and_then(|id| self.find(self.local_def_id_to_hir_id(id)))
     }
 
-    pub fn get_generics(&self, id: LocalDefId) -> Option<&'hir Generics<'hir>> {
+    pub fn get_generics(self, id: LocalDefId) -> Option<&'hir Generics<'hir>> {
         let node = self.tcx.hir_owner(id)?;
         match node.node {
             OwnerNode::ImplItem(impl_item) => Some(&impl_item.generics),
@@ -386,27 +386,27 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn item(&self, id: ItemId) -> &'hir Item<'hir> {
+    pub fn item(self, id: ItemId) -> &'hir Item<'hir> {
         self.tcx.hir_owner(id.def_id).unwrap().node.expect_item()
     }
 
-    pub fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir> {
+    pub fn trait_item(self, id: TraitItemId) -> &'hir TraitItem<'hir> {
         self.tcx.hir_owner(id.def_id).unwrap().node.expect_trait_item()
     }
 
-    pub fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> {
+    pub fn impl_item(self, id: ImplItemId) -> &'hir ImplItem<'hir> {
         self.tcx.hir_owner(id.def_id).unwrap().node.expect_impl_item()
     }
 
-    pub fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> {
+    pub fn foreign_item(self, id: ForeignItemId) -> &'hir ForeignItem<'hir> {
         self.tcx.hir_owner(id.def_id).unwrap().node.expect_foreign_item()
     }
 
-    pub fn body(&self, id: BodyId) -> &'hir Body<'hir> {
+    pub fn body(self, id: BodyId) -> &'hir Body<'hir> {
         self.tcx.hir_owner_nodes(id.hir_id.owner).unwrap().bodies[&id.hir_id.local_id]
     }
 
-    pub fn fn_decl_by_hir_id(&self, hir_id: HirId) -> Option<&'hir FnDecl<'hir>> {
+    pub fn fn_decl_by_hir_id(self, hir_id: HirId) -> Option<&'hir FnDecl<'hir>> {
         if let Some(node) = self.find(hir_id) {
             fn_decl(node)
         } else {
@@ -414,7 +414,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn fn_sig_by_hir_id(&self, hir_id: HirId) -> Option<&'hir FnSig<'hir>> {
+    pub fn fn_sig_by_hir_id(self, hir_id: HirId) -> Option<&'hir FnSig<'hir>> {
         if let Some(node) = self.find(hir_id) {
             fn_sig(node)
         } else {
@@ -422,7 +422,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn enclosing_body_owner(&self, hir_id: HirId) -> HirId {
+    pub fn enclosing_body_owner(self, hir_id: HirId) -> HirId {
         for (parent, _) in self.parent_iter(hir_id) {
             if let Some(body) = self.maybe_body_owned_by(parent) {
                 return self.body_owner(body);
@@ -435,24 +435,24 @@ impl<'hir> Map<'hir> {
     /// Returns the `HirId` that corresponds to the definition of
     /// which this is the body of, i.e., a `fn`, `const` or `static`
     /// item (possibly associated), a closure, or a `hir::AnonConst`.
-    pub fn body_owner(&self, BodyId { hir_id }: BodyId) -> HirId {
+    pub fn body_owner(self, BodyId { hir_id }: BodyId) -> HirId {
         let parent = self.get_parent_node(hir_id);
         assert!(self.find(parent).map_or(false, |n| is_body_owner(n, hir_id)));
         parent
     }
 
-    pub fn body_owner_def_id(&self, id: BodyId) -> LocalDefId {
+    pub fn body_owner_def_id(self, id: BodyId) -> LocalDefId {
         self.local_def_id(self.body_owner(id))
     }
 
     /// Given a `HirId`, returns the `BodyId` associated with it,
     /// if the node is a body owner, otherwise returns `None`.
-    pub fn maybe_body_owned_by(&self, hir_id: HirId) -> Option<BodyId> {
+    pub fn maybe_body_owned_by(self, hir_id: HirId) -> Option<BodyId> {
         self.find(hir_id).map(associated_body).flatten()
     }
 
     /// Given a body owner's id, returns the `BodyId` associated with it.
-    pub fn body_owned_by(&self, id: HirId) -> BodyId {
+    pub fn body_owned_by(self, id: HirId) -> BodyId {
         self.maybe_body_owned_by(id).unwrap_or_else(|| {
             span_bug!(
                 self.span(id),
@@ -462,7 +462,7 @@ impl<'hir> Map<'hir> {
         })
     }
 
-    pub fn body_param_names(&self, id: BodyId) -> impl Iterator<Item = Ident> + 'hir {
+    pub fn body_param_names(self, id: BodyId) -> impl Iterator<Item = Ident> + 'hir {
         self.body(id).params.iter().map(|arg| match arg.pat.kind {
             PatKind::Binding(_, _, ident, _) => ident,
             _ => Ident::empty(),
@@ -472,7 +472,7 @@ impl<'hir> Map<'hir> {
     /// Returns the `BodyOwnerKind` of this `LocalDefId`.
     ///
     /// Panics if `LocalDefId` does not have an associated body.
-    pub fn body_owner_kind(&self, id: HirId) -> BodyOwnerKind {
+    pub fn body_owner_kind(self, id: HirId) -> BodyOwnerKind {
         match self.get(id) {
             Node::Item(&Item { kind: ItemKind::Const(..), .. })
             | Node::TraitItem(&TraitItem { kind: TraitItemKind::Const(..), .. })
@@ -495,7 +495,7 @@ impl<'hir> Map<'hir> {
     /// This should only be used for determining the context of a body, a return
     /// value of `Some` does not always suggest that the owner of the body is `const`,
     /// just that it has to be checked as if it were.
-    pub fn body_const_context(&self, did: LocalDefId) -> Option<ConstContext> {
+    pub fn body_const_context(self, did: LocalDefId) -> Option<ConstContext> {
         let hir_id = self.local_def_id_to_hir_id(did);
         let ccx = match self.body_owner_kind(hir_id) {
             BodyOwnerKind::Const => ConstContext::Const,
@@ -549,7 +549,7 @@ impl<'hir> Map<'hir> {
         });
     }
 
-    pub fn ty_param_owner(&self, id: HirId) -> LocalDefId {
+    pub fn ty_param_owner(self, id: HirId) -> LocalDefId {
         match self.get(id) {
             Node::Item(&Item { kind: ItemKind::Trait(..) | ItemKind::TraitAlias(..), .. }) => {
                 id.expect_owner()
@@ -559,7 +559,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn ty_param_name(&self, id: HirId) -> Symbol {
+    pub fn ty_param_name(self, id: HirId) -> Symbol {
         match self.get(id) {
             Node::Item(&Item { kind: ItemKind::Trait(..) | ItemKind::TraitAlias(..), .. }) => {
                 kw::SelfUpper
@@ -569,18 +569,18 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn trait_impls(&self, trait_did: DefId) -> &'hir [LocalDefId] {
+    pub fn trait_impls(self, trait_did: DefId) -> &'hir [LocalDefId] {
         self.tcx.all_local_trait_impls(()).get(&trait_did).map_or(&[], |xs| &xs[..])
     }
 
     /// Gets the attributes on the crate. This is preferable to
     /// invoking `krate.attrs` because it registers a tighter
     /// dep-graph access.
-    pub fn krate_attrs(&self) -> &'hir [ast::Attribute] {
+    pub fn krate_attrs(self) -> &'hir [ast::Attribute] {
         self.attrs(CRATE_HIR_ID)
     }
 
-    pub fn get_module(&self, module: LocalDefId) -> (&'hir Mod<'hir>, Span, HirId) {
+    pub fn get_module(self, module: LocalDefId) -> (&'hir Mod<'hir>, Span, HirId) {
         let hir_id = HirId::make_owner(module);
         match self.tcx.hir_owner(module).map(|o| o.node) {
             Some(OwnerNode::Item(&Item { span, kind: ItemKind::Mod(ref m), .. })) => {
@@ -620,7 +620,7 @@ impl<'hir> Map<'hir> {
     /// follows lexical scoping rules -- then you want a different
     /// approach. You should override `visit_nested_item` in your
     /// visitor and then call `intravisit::walk_crate` instead.
-    pub fn visit_all_item_likes<V>(&self, visitor: &mut V)
+    pub fn visit_all_item_likes<V>(self, visitor: &mut V)
     where
         V: itemlikevisit::ItemLikeVisitor<'hir>,
     {
@@ -637,7 +637,7 @@ impl<'hir> Map<'hir> {
     }
 
     /// A parallel version of `visit_all_item_likes`.
-    pub fn par_visit_all_item_likes<V>(&self, visitor: &V)
+    pub fn par_visit_all_item_likes<V>(self, visitor: &V)
     where
         V: itemlikevisit::ParItemLikeVisitor<'hir> + Sync + Send,
     {
@@ -653,7 +653,7 @@ impl<'hir> Map<'hir> {
         })
     }
 
-    pub fn visit_item_likes_in_module<V>(&self, module: LocalDefId, visitor: &mut V)
+    pub fn visit_item_likes_in_module<V>(self, module: LocalDefId, visitor: &mut V)
     where
         V: ItemLikeVisitor<'hir>,
     {
@@ -676,7 +676,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn for_each_module(&self, f: impl Fn(LocalDefId)) {
+    pub fn for_each_module(self, f: impl Fn(LocalDefId)) {
         let mut queue = VecDeque::new();
         queue.push_back(CRATE_DEF_ID);
 
@@ -689,12 +689,12 @@ impl<'hir> Map<'hir> {
 
     #[cfg(not(parallel_compiler))]
     #[inline]
-    pub fn par_for_each_module(&self, f: impl Fn(LocalDefId)) {
+    pub fn par_for_each_module(self, f: impl Fn(LocalDefId)) {
         self.for_each_module(f)
     }
 
     #[cfg(parallel_compiler)]
-    pub fn par_for_each_module(&self, f: impl Fn(LocalDefId) + Sync) {
+    pub fn par_for_each_module(self, f: impl Fn(LocalDefId) + Sync) {
         use rustc_data_structures::sync::{par_iter, ParallelIterator};
         par_iter_submodules(self.tcx, CRATE_DEF_ID, &f);
 
@@ -721,7 +721,7 @@ impl<'hir> Map<'hir> {
     }
 
     /// Checks if the node is left-hand side of an assignment.
-    pub fn is_lhs(&self, id: HirId) -> bool {
+    pub fn is_lhs(self, id: HirId) -> bool {
         match self.find(self.get_parent_node(id)) {
             Some(Node::Expr(expr)) => match expr.kind {
                 ExprKind::Assign(lhs, _rhs, _span) => lhs.hir_id == id,
@@ -733,7 +733,7 @@ impl<'hir> Map<'hir> {
 
     /// Whether the expression pointed at by `hir_id` belongs to a `const` evaluation context.
     /// Used exclusively for diagnostics, to avoid suggestion function calls.
-    pub fn is_inside_const_context(&self, hir_id: HirId) -> bool {
+    pub fn is_inside_const_context(self, hir_id: HirId) -> bool {
         self.body_const_context(self.local_def_id(self.enclosing_body_owner(hir_id))).is_some()
     }
 
@@ -759,7 +759,7 @@ impl<'hir> Map<'hir> {
     ///     false
     /// }
     /// ```
-    pub fn get_return_block(&self, id: HirId) -> Option<HirId> {
+    pub fn get_return_block(self, id: HirId) -> Option<HirId> {
         let mut iter = self.parent_iter(id).peekable();
         let mut ignore_tail = false;
         if let Some(node) = self.find(id) {
@@ -799,7 +799,7 @@ impl<'hir> Map<'hir> {
     /// parent item is in this map. The "parent item" is the closest parent node
     /// in the HIR which is recorded by the map and is an item, either an item
     /// in a module, trait, or impl.
-    pub fn get_parent_item(&self, hir_id: HirId) -> LocalDefId {
+    pub fn get_parent_item(self, hir_id: HirId) -> LocalDefId {
         if let Some((def_id, _node)) = self.parent_owner_iter(hir_id).next() {
             def_id
         } else {
@@ -809,7 +809,7 @@ impl<'hir> Map<'hir> {
 
     /// Returns the `HirId` of `id`'s nearest module parent, or `id` itself if no
     /// module parent is in this map.
-    pub(super) fn get_module_parent_node(&self, hir_id: HirId) -> LocalDefId {
+    pub(super) fn get_module_parent_node(self, hir_id: HirId) -> LocalDefId {
         for (def_id, node) in self.parent_owner_iter(hir_id) {
             if let OwnerNode::Item(&Item { kind: ItemKind::Mod(_), .. }) = node {
                 return def_id;
@@ -823,7 +823,7 @@ impl<'hir> Map<'hir> {
     ///
     /// Used by error reporting when there's a type error in an if or match arm caused by the
     /// expression needing to be unit.
-    pub fn get_if_cause(&self, hir_id: HirId) -> Option<&'hir Expr<'hir>> {
+    pub fn get_if_cause(self, hir_id: HirId) -> Option<&'hir Expr<'hir>> {
         for (_, node) in self.parent_iter(hir_id) {
             match node {
                 Node::Item(_)
@@ -841,7 +841,7 @@ impl<'hir> Map<'hir> {
     }
 
     /// Returns the nearest enclosing scope. A scope is roughly an item or block.
-    pub fn get_enclosing_scope(&self, hir_id: HirId) -> Option<HirId> {
+    pub fn get_enclosing_scope(self, hir_id: HirId) -> Option<HirId> {
         for (hir_id, node) in self.parent_iter(hir_id) {
             if let Node::Item(Item {
                 kind:
@@ -868,7 +868,7 @@ impl<'hir> Map<'hir> {
     }
 
     /// Returns the defining scope for an opaque type definition.
-    pub fn get_defining_scope(&self, id: HirId) -> HirId {
+    pub fn get_defining_scope(self, id: HirId) -> HirId {
         let mut scope = id;
         loop {
             scope = self.get_enclosing_scope(scope).unwrap_or(CRATE_HIR_ID);
@@ -878,7 +878,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn get_foreign_abi(&self, hir_id: HirId) -> Abi {
+    pub fn get_foreign_abi(self, hir_id: HirId) -> Abi {
         let parent = self.get_parent_item(hir_id);
         if let Some(node) = self.tcx.hir_owner(parent) {
             if let OwnerNode::Item(Item { kind: ItemKind::ForeignMod { abi, .. }, .. }) = node.node
@@ -892,35 +892,35 @@ impl<'hir> Map<'hir> {
         )
     }
 
-    pub fn expect_item(&self, id: LocalDefId) -> &'hir Item<'hir> {
+    pub fn expect_item(self, id: LocalDefId) -> &'hir Item<'hir> {
         match self.tcx.hir_owner(id) {
             Some(Owner { node: OwnerNode::Item(item), .. }) => item,
             _ => bug!("expected item, found {}", self.node_to_string(HirId::make_owner(id))),
         }
     }
 
-    pub fn expect_impl_item(&self, id: LocalDefId) -> &'hir ImplItem<'hir> {
+    pub fn expect_impl_item(self, id: LocalDefId) -> &'hir ImplItem<'hir> {
         match self.tcx.hir_owner(id) {
             Some(Owner { node: OwnerNode::ImplItem(item), .. }) => item,
             _ => bug!("expected impl item, found {}", self.node_to_string(HirId::make_owner(id))),
         }
     }
 
-    pub fn expect_trait_item(&self, id: LocalDefId) -> &'hir TraitItem<'hir> {
+    pub fn expect_trait_item(self, id: LocalDefId) -> &'hir TraitItem<'hir> {
         match self.tcx.hir_owner(id) {
             Some(Owner { node: OwnerNode::TraitItem(item), .. }) => item,
             _ => bug!("expected trait item, found {}", self.node_to_string(HirId::make_owner(id))),
         }
     }
 
-    pub fn expect_variant(&self, id: HirId) -> &'hir Variant<'hir> {
+    pub fn expect_variant(self, id: HirId) -> &'hir Variant<'hir> {
         match self.find(id) {
             Some(Node::Variant(variant)) => variant,
             _ => bug!("expected variant, found {}", self.node_to_string(id)),
         }
     }
 
-    pub fn expect_foreign_item(&self, id: LocalDefId) -> &'hir ForeignItem<'hir> {
+    pub fn expect_foreign_item(self, id: LocalDefId) -> &'hir ForeignItem<'hir> {
         match self.tcx.hir_owner(id) {
             Some(Owner { node: OwnerNode::ForeignItem(item), .. }) => item,
             _ => {
@@ -929,14 +929,14 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn expect_expr(&self, id: HirId) -> &'hir Expr<'hir> {
+    pub fn expect_expr(self, id: HirId) -> &'hir Expr<'hir> {
         match self.find(id) {
             Some(Node::Expr(expr)) => expr,
             _ => bug!("expected expr, found {}", self.node_to_string(id)),
         }
     }
 
-    pub fn opt_name(&self, id: HirId) -> Option<Symbol> {
+    pub fn opt_name(self, id: HirId) -> Option<Symbol> {
         Some(match self.get(id) {
             Node::Item(i) => i.ident.name,
             Node::ForeignItem(fi) => fi.ident.name,
@@ -952,7 +952,7 @@ impl<'hir> Map<'hir> {
         })
     }
 
-    pub fn name(&self, id: HirId) -> Symbol {
+    pub fn name(self, id: HirId) -> Symbol {
         match self.opt_name(id) {
             Some(name) => name,
             None => bug!("no name for {}", self.node_to_string(id)),
@@ -961,18 +961,18 @@ impl<'hir> Map<'hir> {
 
     /// Given a node ID, gets a list of attributes associated with the AST
     /// corresponding to the node-ID.
-    pub fn attrs(&self, id: HirId) -> &'hir [ast::Attribute] {
+    pub fn attrs(self, id: HirId) -> &'hir [ast::Attribute] {
         self.tcx.hir_attrs(id.owner).get(id.local_id)
     }
 
     /// Gets the span of the definition of the specified HIR node.
     /// This is used by `tcx.get_span`
-    pub fn span(&self, hir_id: HirId) -> Span {
+    pub fn span(self, hir_id: HirId) -> Span {
         self.opt_span(hir_id)
             .unwrap_or_else(|| bug!("hir::map::Map::span: id not in map: {:?}", hir_id))
     }
 
-    pub fn opt_span(&self, hir_id: HirId) -> Option<Span> {
+    pub fn opt_span(self, hir_id: HirId) -> Option<Span> {
         let span = match self.find(hir_id)? {
             Node::Param(param) => param.span,
             Node::Item(item) => match &item.kind {
@@ -1021,7 +1021,7 @@ impl<'hir> Map<'hir> {
 
     /// Like `hir.span()`, but includes the body of function items
     /// (instead of just the function header)
-    pub fn span_with_body(&self, hir_id: HirId) -> Span {
+    pub fn span_with_body(self, hir_id: HirId) -> Span {
         match self.find(hir_id) {
             Some(Node::TraitItem(item)) => item.span,
             Some(Node::ImplItem(impl_item)) => impl_item.span,
@@ -1031,11 +1031,11 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn span_if_local(&self, id: DefId) -> Option<Span> {
+    pub fn span_if_local(self, id: DefId) -> Option<Span> {
         id.as_local().and_then(|id| self.opt_span(self.local_def_id_to_hir_id(id)))
     }
 
-    pub fn res_span(&self, res: Res) -> Option<Span> {
+    pub fn res_span(self, res: Res) -> Option<Span> {
         match res {
             Res::Err => None,
             Res::Local(id) => Some(self.span(id)),
@@ -1045,13 +1045,13 @@ impl<'hir> Map<'hir> {
 
     /// Get a representation of this `id` for debugging purposes.
     /// NOTE: Do NOT use this in diagnostics!
-    pub fn node_to_string(&self, id: HirId) -> String {
+    pub fn node_to_string(self, id: HirId) -> String {
         hir_id_to_string(self, id)
     }
 
     /// Returns the HirId of `N` in `struct Foo<const N: usize = { ... }>` when
     /// called with the HirId for the `{ ... }` anon const
-    pub fn opt_const_param_default_param_hir_id(&self, anon_const: HirId) -> Option<HirId> {
+    pub fn opt_const_param_default_param_hir_id(self, anon_const: HirId) -> Option<HirId> {
         match self.get(self.get_parent_node(anon_const)) {
             Node::GenericParam(GenericParam {
                 hir_id: param_id,
@@ -1065,27 +1065,27 @@ impl<'hir> Map<'hir> {
 
 impl<'hir> intravisit::Map<'hir> for Map<'hir> {
     fn find(&self, hir_id: HirId) -> Option<Node<'hir>> {
-        self.find(hir_id)
+        (*self).find(hir_id)
     }
 
     fn body(&self, id: BodyId) -> &'hir Body<'hir> {
-        self.body(id)
+        (*self).body(id)
     }
 
     fn item(&self, id: ItemId) -> &'hir Item<'hir> {
-        self.item(id)
+        (*self).item(id)
     }
 
     fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir> {
-        self.trait_item(id)
+        (*self).trait_item(id)
     }
 
     fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> {
-        self.impl_item(id)
+        (*self).impl_item(id)
     }
 
     fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> {
-        self.foreign_item(id)
+        (*self).foreign_item(id)
     }
 }
 
@@ -1154,7 +1154,7 @@ fn upstream_crates(tcx: TyCtxt<'_>) -> Vec<(StableCrateId, Svh)> {
     upstream_crates
 }
 
-fn hir_id_to_string(map: &Map<'_>, id: HirId) -> String {
+fn hir_id_to_string(map: Map<'_>, id: HirId) -> String {
     let id_str = format!(" (hir_id={})", id);
 
     let path_str = || {

compiler/rustc_resolve/src/late/lifetimes.rs

@@ -41,9 +41,9 @@ pub enum LifetimeUseSet<'tcx> {
 }
 
 trait RegionExt {
-    fn early(hir_map: &Map<'_>, index: &mut u32, param: &GenericParam<'_>) -> (ParamName, Region);
+    fn early(hir_map: Map<'_>, index: &mut u32, param: &GenericParam<'_>) -> (ParamName, Region);
 
-    fn late(index: u32, hir_map: &Map<'_>, param: &GenericParam<'_>) -> (ParamName, Region);
+    fn late(index: u32, hir_map: Map<'_>, param: &GenericParam<'_>) -> (ParamName, Region);
 
     fn late_anon(named_late_bound_vars: u32, index: &Cell<u32>) -> Region;
 
@@ -59,7 +59,7 @@ trait RegionExt {
 }
 
 impl RegionExt for Region {
-    fn early(hir_map: &Map<'_>, index: &mut u32, param: &GenericParam<'_>) -> (ParamName, Region) {
+    fn early(hir_map: Map<'_>, index: &mut u32, param: &GenericParam<'_>) -> (ParamName, Region) {
         let i = *index;
         *index += 1;
         let def_id = hir_map.local_def_id(param.hir_id);
@@ -68,7 +68,7 @@ impl RegionExt for Region {
         (param.name.normalize_to_macros_2_0(), Region::EarlyBound(i, def_id.to_def_id(), origin))
     }
 
-    fn late(idx: u32, hir_map: &Map<'_>, param: &GenericParam<'_>) -> (ParamName, Region) {
+    fn late(idx: u32, hir_map: Map<'_>, param: &GenericParam<'_>) -> (ParamName, Region) {
         let depth = ty::INNERMOST;
         let def_id = hir_map.local_def_id(param.hir_id);
         let origin = LifetimeDefOrigin::from_param(param);
@@ -817,7 +817,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     .iter()
                     .filter_map(|param| match param.kind {
                         GenericParamKind::Lifetime { .. } => {
-                            Some(Region::early(&self.tcx.hir(), &mut index, param))
+                            Some(Region::early(self.tcx.hir(), &mut index, param))
                         }
                         GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {
                             non_lifetime_count += 1;
@@ -888,7 +888,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     .filter(|param| matches!(param.kind, GenericParamKind::Lifetime { .. }))
                     .enumerate()
                     .map(|(late_bound_idx, param)| {
-                        let pair = Region::late(late_bound_idx as u32, &self.tcx.hir(), param);
+                        let pair = Region::late(late_bound_idx as u32, self.tcx.hir(), param);
                         let r = late_region_as_bound_region(self.tcx, &pair.1);
                         (pair, r)
                     })
@@ -1045,7 +1045,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 for param in generics.params {
                     match param.kind {
                         GenericParamKind::Lifetime { .. } => {
-                            let (name, reg) = Region::early(&self.tcx.hir(), &mut index, &param);
+                            let (name, reg) = Region::early(self.tcx.hir(), &mut index, &param);
                             let Region::EarlyBound(_, def_id, _) = reg else {
                                 bug!();
                             };
@@ -1145,7 +1145,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     .iter()
                     .filter_map(|param| match param.kind {
                         GenericParamKind::Lifetime { .. } => {
-                            Some(Region::early(&self.tcx.hir(), &mut index, param))
+                            Some(Region::early(self.tcx.hir(), &mut index, param))
                         }
                         GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {
                             non_lifetime_count += 1;
@@ -1214,7 +1214,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     .iter()
                     .filter_map(|param| match param.kind {
                         GenericParamKind::Lifetime { .. } => {
-                            Some(Region::early(&self.tcx.hir(), &mut index, param))
+                            Some(Region::early(self.tcx.hir(), &mut index, param))
                         }
                         GenericParamKind::Const { .. } | GenericParamKind::Type { .. } => {
                             non_lifetime_count += 1;
@@ -1368,7 +1368,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                                 .enumerate()
                                 .map(|(late_bound_idx, param)| {
                                     let pair =
-                                        Region::late(late_bound_idx as u32, &this.tcx.hir(), param);
+                                        Region::late(late_bound_idx as u32, this.tcx.hir(), param);
                                     let r = late_region_as_bound_region(this.tcx, &pair.1);
                                     (pair, r)
                                 })
@@ -1463,11 +1463,8 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
             .filter(|param| matches!(param.kind, GenericParamKind::Lifetime { .. }))
             .enumerate()
             .map(|(late_bound_idx, param)| {
-                let pair = Region::late(
+                let pair =
-                    initial_bound_vars + late_bound_idx as u32,
+                    Region::late(initial_bound_vars + late_bound_idx as u32, self.tcx.hir(), param);
-                    &self.tcx.hir(),
-                    param,
-                );
                 let r = late_region_as_bound_region(self.tcx, &pair.1);
                 lifetimes.insert(pair.0, pair.1);
                 r
@@ -2194,9 +2191,9 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                     if self.map.late_bound.contains(&param.hir_id) {
                         let late_bound_idx = named_late_bound_vars;
                         named_late_bound_vars += 1;
-                        Some(Region::late(late_bound_idx, &self.tcx.hir(), param))
+                        Some(Region::late(late_bound_idx, self.tcx.hir(), param))
                     } else {
-                        Some(Region::early(&self.tcx.hir(), &mut next_early_index, param))
+                        Some(Region::early(self.tcx.hir(), &mut next_early_index, param))
                     }
                 }
                 GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {
@@ -2216,7 +2213,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
             })
             .enumerate()
             .map(|(late_bound_idx, param)| {
-                let pair = Region::late(late_bound_idx as u32, &self.tcx.hir(), param);
+                let pair = Region::late(late_bound_idx as u32, self.tcx.hir(), param);
                 late_region_as_bound_region(self.tcx, &pair.1)
             })
             .collect();

compiler/rustc_save_analysis/src/dump_visitor.rs

@@ -262,7 +262,7 @@ impl<'tcx> DumpVisitor<'tcx> {
     ) {
         debug!("process_method: {:?}:{}", def_id, ident);
 
-        let map = &self.tcx.hir();
+        let map = self.tcx.hir();
         let hir_id = map.local_def_id_to_hir_id(def_id);
         self.nest_typeck_results(def_id, |v| {
             if let Some(mut method_data) = v.save_ctxt.get_method_data(hir_id, ident, span) {
@@ -361,7 +361,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         ty_params: &'tcx hir::Generics<'tcx>,
         body: hir::BodyId,
     ) {
-        let map = &self.tcx.hir();
+        let map = self.tcx.hir();
         self.nest_typeck_results(item.def_id, |v| {
             let body = map.body(body);
             if let Some(fn_data) = v.save_ctxt.get_item_data(item) {
@@ -626,7 +626,7 @@ impl<'tcx> DumpVisitor<'tcx> {
             }
         }
 
-        let map = &self.tcx.hir();
+        let map = self.tcx.hir();
         self.nest_typeck_results(item.def_id, |v| {
             v.visit_ty(&impl_.self_ty);
             if let Some(trait_ref) = &impl_.of_trait {
@@ -716,7 +716,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         // walk generics and methods
         self.process_generic_params(generics, &qualname, item.hir_id());
         for method in methods {
-            let map = &self.tcx.hir();
+            let map = self.tcx.hir();
             self.process_trait_item(map.trait_item(method.id), item.def_id.to_def_id())
         }
     }

compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs

@@ -77,7 +77,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
     /// Used to set on_unimplemented's `ItemContext`
     /// to be the enclosing (async) block/function/closure
     fn describe_enclosure(&self, hir_id: hir::HirId) -> Option<&'static str> {
-        let hir = &self.tcx.hir();
+        let hir = self.tcx.hir();
         let node = hir.find(hir_id)?;
         match &node {
             hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(sig, _, body_id), .. }) => {

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -1663,7 +1663,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let table_owner = table.borrow().hir_owner;
                 let generics = self.tcx.generics_of(table_owner.to_def_id());
                 let type_param = generics.type_param(param, self.tcx);
-                let hir = &self.tcx.hir();
+                let hir = self.tcx.hir();
                 if let Some(def_id) = type_param.def_id.as_local() {
                     let id = hir.local_def_id_to_hir_id(def_id);
                     // Get the `hir::Param` to verify whether it already has any bounds.