Auto merge of rust-lang#88222 - jyn514:shared-cache, r=GuillaumeGomez

bors · bors · commit 3b3ce374d203 · 2021-08-26T08:04:29.000Z
rustdoc: Move Cache from Context to SharedContext

r? `@camelid`
diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs
@@ -62,16 +62,6 @@ crate struct Context<'tcx> {
     ///
     /// [#82381]: https://github.com/rust-lang/rust/issues/82381
     crate shared: Rc<SharedContext<'tcx>>,
-    /// The [`Cache`] used during rendering.
-    ///
-    /// Ideally the cache would be in [`SharedContext`], but it's mutated
-    /// between when the `SharedContext` is created and when `Context`
-    /// is created, so more refactoring would be needed.
-    ///
-    /// It's immutable once in `Context`, so it's not as bad that it's not in
-    /// `SharedContext`.
-    // FIXME: move `cache` to `SharedContext`
-    crate cache: Rc<Cache>,
     /// This flag indicates whether `[src]` links should be generated or not. If
     /// the source files are present in the html rendering, then this will be
     /// `true`.
@@ -80,7 +70,7 @@ crate struct Context<'tcx> {
 
 // `Context` is cloned a lot, so we don't want the size to grow unexpectedly.
 #[cfg(target_arch = "x86_64")]
-rustc_data_structures::static_assert_size!(Context<'_>, 112);
+rustc_data_structures::static_assert_size!(Context<'_>, 104);
 
 /// Shared mutable state used in [`Context`] and elsewhere.
 crate struct SharedContext<'tcx> {
@@ -132,6 +122,8 @@ crate struct SharedContext<'tcx> {
     /// Correspondance map used to link types used in the source code pages to allow to click on
     /// links to jump to the type's definition.
     crate span_correspondance_map: FxHashMap<rustc_span::Span, LinkFromSrc>,
+    /// The [`Cache`] used during rendering.
+    crate cache: Cache,
 }
 
 impl SharedContext<'_> {
@@ -162,7 +154,7 @@ impl<'tcx> Context<'tcx> {
     }
 
     pub(crate) fn cache(&self) -> &Cache {
-        &self.cache
+        &self.shared.cache
     }
 
     pub(super) fn sess(&self) -> &'tcx Session {
@@ -237,7 +229,7 @@ impl<'tcx> Context<'tcx> {
                 &self.shared.style_files,
             )
         } else {
-            if let Some(&(ref names, ty)) = self.cache.paths.get(&it.def_id.expect_def_id()) {
+            if let Some(&(ref names, ty)) = self.cache().paths.get(&it.def_id.expect_def_id()) {
                 let mut path = String::new();
                 for name in &names[..names.len() - 1] {
                     path.push_str(name);
@@ -326,7 +318,7 @@ impl<'tcx> Context<'tcx> {
                 return None;
             }
         } else {
-            let (krate, src_root) = match *self.cache.extern_locations.get(&cnum)? {
+            let (krate, src_root) = match *self.cache().extern_locations.get(&cnum)? {
                 ExternalLocation::Local => {
                     let e = ExternalCrate { crate_num: cnum };
                     (e.name(self.tcx()), e.src_root(self.tcx()))
@@ -487,6 +479,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             show_type_layout,
             templates,
             span_correspondance_map: matches,
+            cache,
         };
 
         // Add the default themes to the `Vec` of stylepaths
@@ -511,7 +504,6 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             render_redirect_pages: false,
             id_map: RefCell::new(id_map),
             shared: Rc::new(scx),
-            cache: Rc::new(cache),
             include_sources,
         };
 
@@ -520,7 +512,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
         }
 
         // Build our search index
-        let index = build_index(&krate, Rc::get_mut(&mut cx.cache).unwrap(), tcx);
+        let index = build_index(&krate, &mut Rc::get_mut(&mut cx.shared).unwrap().cache, tcx);
 
         // Write shared runs within a flock; disable thread dispatching of IO temporarily.
         Rc::get_mut(&mut cx.shared).unwrap().fs.set_sync_only(true);
@@ -536,7 +528,6 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             render_redirect_pages: self.render_redirect_pages,
             id_map: RefCell::new(IdMap::new()),
             shared: Rc::clone(&self.shared),
-            cache: Rc::clone(&self.cache),
             include_sources: self.include_sources,
         }
     }
@@ -561,7 +552,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             extra_scripts: &[],
             static_extra_scripts: &[],
         };
-        let sidebar = if let Some(ref version) = self.cache.crate_version {
+        let sidebar = if let Some(ref version) = self.shared.cache.crate_version {
             format!(
                 "<h2 class=\"location\">Crate {}</h2>\
                      <div class=\"block version\">\
@@ -722,7 +713,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
     }
 
     fn cache(&self) -> &Cache {
-        &self.cache
+        &self.shared.cache
     }
 }
 
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
@@ -1012,11 +1012,11 @@ fn render_assoc_items(
     what: AssocItemRender<'_>,
 ) {
     info!("Documenting associated items of {:?}", containing_item.name);
-    let v = match cx.cache.impls.get(&it) {
+    let cache = cx.cache();
+    let v = match cache.impls.get(&it) {
         Some(v) => v,
         None => return,
     };
-    let cache = cx.cache();
     let (non_trait, traits): (Vec<_>, _) = v.iter().partition(|i| i.inner_impl().trait_.is_none());
     if !non_trait.is_empty() {
         let render_mode = match what {
@@ -1063,11 +1063,11 @@ fn render_assoc_items(
     if !traits.is_empty() {
         let deref_impl = traits
             .iter()
-            .find(|t| t.inner_impl().trait_.def_id_full(cache) == cx.cache.deref_trait_did);
+            .find(|t| t.inner_impl().trait_.def_id_full(cache) == cache.deref_trait_did);
         if let Some(impl_) = deref_impl {
             let has_deref_mut = traits
                 .iter()
-                .any(|t| t.inner_impl().trait_.def_id_full(cache) == cx.cache.deref_mut_trait_did);
+                .any(|t| t.inner_impl().trait_.def_id_full(cache) == cache.deref_mut_trait_did);
             render_deref_methods(w, cx, impl_, containing_item, has_deref_mut);
         }
         let (synthetic, concrete): (Vec<&&Impl>, Vec<&&Impl>) =
@@ -1122,6 +1122,7 @@ fn render_deref_methods(
     container_item: &clean::Item,
     deref_mut: bool,
 ) {
+    let cache = cx.cache();
     let deref_type = impl_.inner_impl().trait_.as_ref().unwrap();
     let (target, real_target) = impl_
         .inner_impl()
@@ -1138,8 +1139,8 @@ fn render_deref_methods(
     debug!("Render deref methods for {:#?}, target {:#?}", impl_.inner_impl().for_, target);
     let what =
         AssocItemRender::DerefFor { trait_: deref_type, type_: real_target, deref_mut_: deref_mut };
-    if let Some(did) = target.def_id_full(cx.cache()) {
-        if let Some(type_did) = impl_.inner_impl().for_.def_id_full(cx.cache()) {
+    if let Some(did) = target.def_id_full(cache) {
+        if let Some(type_did) = impl_.inner_impl().for_.def_id_full(cache) {
             // `impl Deref<Target = S> for S`
             if did == type_did {
                 // Avoid infinite cycles
@@ -1149,7 +1150,7 @@ fn render_deref_methods(
         render_assoc_items(w, cx, container_item, did, what);
     } else {
         if let Some(prim) = target.primitive_type() {
-            if let Some(&did) = cx.cache.primitive_locations.get(&prim) {
+            if let Some(&did) = cache.primitive_locations.get(&prim) {
                 render_assoc_items(w, cx, container_item, did, what);
             }
         }
@@ -1286,7 +1287,7 @@ fn render_impl(
         let render_method_item = 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.cache())
             }
         };
 
@@ -1678,7 +1679,7 @@ fn print_sidebar(cx: &Context<'_>, it: &clean::Item, buffer: &mut Buffer) {
     }
 
     if it.is_crate() {
-        if let Some(ref version) = cx.cache.crate_version {
+        if let Some(ref version) = cx.cache().crate_version {
             write!(
                 buffer,
                 "<div class=\"block version\">\
@@ -1825,18 +1826,16 @@ fn small_url_encode(s: String) -> String {
 
 fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
     let did = it.def_id.expect_def_id();
-    if let Some(v) = cx.cache.impls.get(&did) {
+    let cache = cx.cache();
+    if let Some(v) = cache.impls.get(&did) {
         let mut used_links = FxHashSet::default();
-        let cache = cx.cache();
 
         {
             let used_links_bor = &mut used_links;
             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, &cx.cache)
-                })
+                .flat_map(move |i| get_methods(i.inner_impl(), false, used_links_bor, false, cache))
                 .collect::<Vec<_>>();
             if !ret.is_empty() {
                 // We want links' order to be reproducible so we don't use unstable sort.
@@ -1857,7 +1856,7 @@ fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
             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.cache.deref_trait_did)
+                .find(|i| i.inner_impl().trait_.def_id_full(cache) == cache.deref_trait_did)
             {
                 sidebar_deref_methods(cx, out, impl_, v);
             }
@@ -2117,15 +2116,15 @@ fn sidebar_trait(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, t: &clean
         "</div>",
     );
 
-    if let Some(implementors) = cx.cache.implementors.get(&it.def_id.expect_def_id()) {
-        let cache = cx.cache();
+    let cache = cx.cache();
+    if let Some(implementors) = cache.implementors.get(&it.def_id.expect_def_id()) {
         let mut res = implementors
             .iter()
             .filter(|i| {
                 i.inner_impl()
                     .for_
                     .def_id_full(cache)
-                    .map_or(false, |d| !cx.cache.paths.contains_key(&d))
+                    .map_or(false, |d| !cache.paths.contains_key(&d))
             })
             .filter_map(|i| extract_for_impl_name(&i.impl_item, cx))
             .collect::<Vec<_>>();
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
@@ -690,7 +690,8 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
     // If there are methods directly on this trait object, render them here.
     render_assoc_items(w, cx, it, it.def_id.expect_def_id(), AssocItemRender::All);
 
-    if let Some(implementors) = cx.cache.implementors.get(&it.def_id.expect_def_id()) {
+    let cache = cx.cache();
+    if let Some(implementors) = cache.implementors.get(&it.def_id.expect_def_id()) {
         // The DefId is for the first Type found with that name. The bool is
         // if any Types with the same name but different DefId have been found.
         let mut implementor_dups: FxHashMap<Symbol, (DefId, bool)> = FxHashMap::default();
@@ -712,10 +713,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         }
 
         let (local, foreign) = implementors.iter().partition::<Vec<_>, _>(|i| {
-            i.inner_impl()
-                .for_
-                .def_id_full(cx.cache())
-                .map_or(true, |d| cx.cache.paths.contains_key(&d))
+            i.inner_impl().for_.def_id_full(cache).map_or(true, |d| cache.paths.contains_key(&d))
         });
 
         let (mut synthetic, mut concrete): (Vec<&&Impl>, Vec<&&Impl>) =
@@ -772,7 +770,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
                     it,
                     w,
                     &implementor_dups,
-                    &collect_paths_for_type(implementor.inner_impl().for_.clone(), &cx.cache),
+                    &collect_paths_for_type(implementor.inner_impl().for_.clone(), cache),
                 );
             }
             w.write_str("</div>");
@@ -806,7 +804,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         path = if it.def_id.is_local() {
             cx.current.join("/")
         } else {
-            let (ref path, _) = cx.cache.external_paths[&it.def_id.expect_def_id()];
+            let (ref path, _) = cache.external_paths[&it.def_id.expect_def_id()];
             path[..path.len() - 1].join("/")
         },
         ty = it.type_(),
diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
@@ -518,17 +518,18 @@ pub(super) fn write_shared(
 
     // Update the list of all implementors for traits
     let dst = cx.dst.join("implementors");
-    for (&did, imps) in &cx.cache.implementors {
+    let cache = cx.cache();
+    for (&did, imps) in &cache.implementors {
         // Private modules can leak through to this phase of rustdoc, which
         // could contain implementations for otherwise private types. In some
         // rare cases we could find an implementation for an item which wasn't
         // indexed, so we just skip this step in that case.
         //
         // FIXME: this is a vague explanation for why this can't be a `get`, in
         //        theory it should be...
-        let &(ref remote_path, remote_item_type) = match cx.cache.paths.get(&did) {
+        let &(ref remote_path, remote_item_type) = match cache.paths.get(&did) {
             Some(p) => p,
-            None => match cx.cache.external_paths.get(&did) {
+            None => match cache.external_paths.get(&did) {
                 Some(p) => p,
                 None => continue,
             },
@@ -557,7 +558,7 @@ pub(super) fn write_shared(
                     Some(Implementor {
                         text: imp.inner_impl().print(false, cx).to_string(),
                         synthetic: imp.inner_impl().synthetic,
-                        types: collect_paths_for_type(imp.inner_impl().for_.clone(), cx.cache()),
+                        types: collect_paths_for_type(imp.inner_impl().for_.clone(), cache),
                     })
                 }
             })
@@ -566,7 +567,7 @@ pub(super) fn write_shared(
         // Only create a js file if we have impls to add to it. If the trait is
         // documented locally though we always create the file to avoid dead
         // links.
-        if implementors.is_empty() && !cx.cache.paths.contains_key(&did) {
+        if implementors.is_empty() && !cache.paths.contains_key(&did) {
             continue;
         }
 
