Remove unnecessary Cache.*_did fields

They can be obtained by accessing the `TyCtxt` where they are needed.

src/librustdoc/clean/utils.rs

@@ -29,10 +29,6 @@ crate fn krate(cx: &mut DocContext<'_>) -> Crate {
     let krate = cx.tcx.hir().krate();
     let module = crate::visit_ast::RustdocVisitor::new(cx).visit(krate);
 
-    cx.cache.deref_trait_did = cx.tcx.lang_items().deref_trait();
-    cx.cache.deref_mut_trait_did = cx.tcx.lang_items().deref_mut_trait();
-    cx.cache.owned_box_did = cx.tcx.lang_items().owned_box();
-
     let mut externs = Vec::new();
     for &cnum in cx.tcx.crates(()).iter() {
         externs.push(ExternalCrate { crate_num: cnum });

src/librustdoc/formats/cache.rs

@@ -98,9 +98,6 @@ crate struct Cache {
     stripped_mod: bool,
 
     crate search_index: Vec<IndexItem>,
-    crate deref_trait_did: Option<DefId>,
-    crate deref_mut_trait_did: Option<DefId>,
-    crate owned_box_did: Option<DefId>,
 
     // In rare case where a structure is defined in one module but implemented
     // in another, if the implementing module is parsed before defining module,

src/librustdoc/html/render/mod.rs

@@ -1069,13 +1069,13 @@ fn render_assoc_items(
         return;
     }
     if !traits.is_empty() {
-        let deref_impl = traits
-            .iter()
-            .find(|t| t.inner_impl().trait_.def_id_full(cache) == cache.deref_trait_did);
+        let deref_impl = traits.iter().find(|t| {
+            t.inner_impl().trait_.def_id_full(cache) == cx.tcx().lang_items().deref_trait()
+        });
         if let Some(impl_) = deref_impl {
-            let has_deref_mut = traits
-                .iter()
-                .any(|t| t.inner_impl().trait_.def_id_full(cache) == cache.deref_mut_trait_did);
+            let has_deref_mut = traits.iter().any(|t| {
+                t.inner_impl().trait_.def_id_full(cache) == cx.tcx().lang_items().deref_mut_trait()
+            });
             render_deref_methods(w, cx, impl_, containing_item, has_deref_mut);
         }
         let (synthetic, concrete): (Vec<&&Impl>, Vec<&&Impl>) =
@@ -1165,7 +1165,7 @@ fn render_deref_methods(
     }
 }
 
-fn should_render_item(item: &clean::Item, deref_mut_: bool, cache: &Cache) -> bool {
+fn should_render_item(item: &clean::Item, deref_mut_: bool, cx: &Context<'_>) -> bool {
     let self_type_opt = match *item.kind {
         clean::MethodItem(ref method, _) => method.decl.self_type(),
         clean::TyMethodItem(ref method) => method.decl.self_type(),
@@ -1179,7 +1179,7 @@ fn should_render_item(item: &clean::Item, deref_mut_: bool, cache: &Cache) -> bo
                 (mutability == Mutability::Mut, false, false)
             }
             SelfTy::SelfExplicit(clean::ResolvedPath { did, .. }) => {
-                (false, Some(did) == cache.owned_box_did, false)
+                (false, Some(did) == cx.tcx().lang_items().owned_box(), false)
             }
             SelfTy::SelfValue => (false, false, true),
             _ => (false, false, false),
@@ -1302,7 +1302,7 @@ fn render_impl(
             && match render_mode {
                 RenderMode::Normal => true,
                 RenderMode::ForDeref { mut_: deref_mut_ } => {
-                    should_render_item(&item, deref_mut_, cx.cache())
+                    should_render_item(&item, deref_mut_, cx)
                 }
             };
 
@@ -1800,13 +1800,13 @@ fn get_methods(
     for_deref: bool,
     used_links: &mut FxHashSet<String>,
     deref_mut: bool,
-    cache: &Cache,
+    cx: &Context<'_>,
 ) -> Vec<String> {
     i.items
         .iter()
         .filter_map(|item| match item.name {
             Some(ref name) if !name.is_empty() && item.is_method() => {
-                if !for_deref || should_render_item(item, deref_mut, cache) {
+                if !for_deref || should_render_item(item, deref_mut, cx) {
                     Some(format!(
                         "<a href=\"#{}\">{}</a>",
                         get_next_url(used_links, format!("method.{}", name)),
@@ -1868,7 +1868,7 @@ fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
             let mut ret = v
                 .iter()
                 .filter(|i| i.inner_impl().trait_.is_none())
-                .flat_map(move |i| get_methods(i.inner_impl(), false, used_links_bor, false, cache))
+                .flat_map(move |i| get_methods(i.inner_impl(), false, used_links_bor, false, cx))
                 .collect::<Vec<_>>();
             if !ret.is_empty() {
                 // We want links' order to be reproducible so we don't use unstable sort.
@@ -1886,11 +1886,9 @@ fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
         }
 
         if v.iter().any(|i| i.inner_impl().trait_.is_some()) {
-            if let Some(impl_) = v
-                .iter()
-                .filter(|i| i.inner_impl().trait_.is_some())
-                .find(|i| i.inner_impl().trait_.def_id_full(cache) == cache.deref_trait_did)
-            {
+            if let Some(impl_) = v.iter().filter(|i| i.inner_impl().trait_.is_some()).find(|i| {
+                i.inner_impl().trait_.def_id_full(cache) == cx.tcx().lang_items().deref_trait()
+            }) {
                 sidebar_deref_methods(cx, out, impl_, v);
             }
 
@@ -1988,10 +1986,9 @@ fn sidebar_deref_methods(cx: &Context<'_>, out: &mut Buffer, impl_: &Impl, v: &V
                 }
             }
         }
-        let deref_mut = v
-            .iter()
-            .filter(|i| i.inner_impl().trait_.is_some())
-            .any(|i| i.inner_impl().trait_.def_id_full(c) == c.deref_mut_trait_did);
+        let deref_mut = v.iter().filter(|i| i.inner_impl().trait_.is_some()).any(|i| {
+            i.inner_impl().trait_.def_id_full(c) == cx.tcx().lang_items().deref_mut_trait()
+        });
         let inner_impl = target
             .def_id_full(c)
             .or_else(|| {
@@ -2004,7 +2001,7 @@ fn sidebar_deref_methods(cx: &Context<'_>, out: &mut Buffer, impl_: &Impl, v: &V
             let mut ret = impls
                 .iter()
                 .filter(|i| i.inner_impl().trait_.is_none())
-                .flat_map(|i| get_methods(i.inner_impl(), true, &mut used_links, deref_mut, c))
+                .flat_map(|i| get_methods(i.inner_impl(), true, &mut used_links, deref_mut, cx))
                 .collect::<Vec<_>>();
             if !ret.is_empty() {
                 write!(