Split ID maps in two parts: the constant one and the updated one

Author: GuillaumeGomez

src/librustdoc/html/markdown.rs

@@ -32,7 +32,6 @@ use std::iter::Peekable;
 use std::ops::{ControlFlow, Range};
 use std::path::PathBuf;
 use std::str::{self, CharIndices};
-use std::sync::OnceLock;
 
 use pulldown_cmark::{
     BrokenLink, CodeBlockKind, CowStr, Event, LinkType, Options, Parser, Tag, TagEnd, html,
@@ -1886,83 +1885,81 @@ pub(crate) fn rust_code_blocks(md: &str, extra_info: &ExtraInfo<'_>) -> Vec<Rust
 #[derive(Clone, Default, Debug)]
 pub struct IdMap {
     map: FxHashMap<Cow<'static, str>, usize>,
+    defined_ids: FxHashSet<&'static str>,
     existing_footnotes: usize,
 }
 
-// The map is pre-initialized and cloned each time to avoid reinitializing it repeatedly.
-static DEFAULT_ID_MAP: OnceLock<FxHashSet<Cow<'static, str>>> = OnceLock::new();
-
-fn init_id_map() -> FxHashSet<Cow<'static, str>> {
+fn init_id_map() -> FxHashSet<&'static str> {
     let mut map = FxHashSet::default();
     // This is the list of IDs used in JavaScript.
-    map.insert("help".into());
-    map.insert("settings".into());
-    map.insert("not-displayed".into());
-    map.insert("alternative-display".into());
-    map.insert("search".into());
-    map.insert("crate-search".into());
-    map.insert("crate-search-div".into());
+    map.insert("help");
+    map.insert("settings");
+    map.insert("not-displayed");
+    map.insert("alternative-display");
+    map.insert("search");
+    map.insert("crate-search");
+    map.insert("crate-search-div");
     // This is the list of IDs used in HTML generated in Rust (including the ones
     // used in tera template files).
-    map.insert("themeStyle".into());
-    map.insert("settings-menu".into());
-    map.insert("help-button".into());
-    map.insert("sidebar-button".into());
-    map.insert("main-content".into());
-    map.insert("toggle-all-docs".into());
-    map.insert("all-types".into());
-    map.insert("default-settings".into());
-    map.insert("sidebar-vars".into());
-    map.insert("copy-path".into());
-    map.insert("rustdoc-toc".into());
-    map.insert("rustdoc-modnav".into());
+    map.insert("themeStyle");
+    map.insert("settings-menu");
+    map.insert("help-button");
+    map.insert("sidebar-button");
+    map.insert("main-content");
+    map.insert("toggle-all-docs");
+    map.insert("all-types");
+    map.insert("default-settings");
+    map.insert("sidebar-vars");
+    map.insert("copy-path");
+    map.insert("rustdoc-toc");
+    map.insert("rustdoc-modnav");
     // This is the list of IDs used by rustdoc sections (but still generated by
     // rustdoc).
-    map.insert("fields".into());
-    map.insert("variants".into());
-    map.insert("implementors-list".into());
-    map.insert("synthetic-implementors-list".into());
-    map.insert("foreign-impls".into());
-    map.insert("implementations".into());
-    map.insert("trait-implementations".into());
-    map.insert("synthetic-implementations".into());
-    map.insert("blanket-implementations".into());
-    map.insert("required-associated-types".into());
-    map.insert("provided-associated-types".into());
-    map.insert("provided-associated-consts".into());
-    map.insert("required-associated-consts".into());
-    map.insert("required-methods".into());
-    map.insert("provided-methods".into());
-    map.insert("dyn-compatibility".into());
-    map.insert("implementors".into());
-    map.insert("synthetic-implementors".into());
-    map.insert("implementations-list".into());
-    map.insert("trait-implementations-list".into());
-    map.insert("synthetic-implementations-list".into());
-    map.insert("blanket-implementations-list".into());
-    map.insert("deref-methods".into());
-    map.insert("layout".into());
-    map.insert("aliased-type".into());
+    map.insert("fields");
+    map.insert("variants");
+    map.insert("implementors-list");
+    map.insert("synthetic-implementors-list");
+    map.insert("foreign-impls");
+    map.insert("implementations");
+    map.insert("trait-implementations");
+    map.insert("synthetic-implementations");
+    map.insert("blanket-implementations");
+    map.insert("required-associated-types");
+    map.insert("provided-associated-types");
+    map.insert("provided-associated-consts");
+    map.insert("required-associated-consts");
+    map.insert("required-methods");
+    map.insert("provided-methods");
+    map.insert("dyn-compatibility");
+    map.insert("implementors");
+    map.insert("synthetic-implementors");
+    map.insert("implementations-list");
+    map.insert("trait-implementations-list");
+    map.insert("synthetic-implementations-list");
+    map.insert("blanket-implementations-list");
+    map.insert("deref-methods");
+    map.insert("layout");
+    map.insert("aliased-type");
     map
 }
 
 impl IdMap {
     pub fn new() -> Self {
-        let mut id_map = IdMap { map: FxHashMap::default(), existing_footnotes: 0 };
-        id_map.init_map();
-        id_map
-    }
-
-    #[allow(rustc::potential_query_instability)]
-    fn init_map(&mut self) {
-        for key in DEFAULT_ID_MAP.get_or_init(init_id_map).iter() {
-            self.map.insert(key.clone(), 1);
-        }
+        IdMap { map: FxHashMap::default(), defined_ids: init_id_map(), existing_footnotes: 0 }
     }
 
     pub(crate) fn derive<S: AsRef<str> + ToString>(&mut self, candidate: S) -> String {
         let id = match self.map.get_mut(candidate.as_ref()) {
-            None => candidate.to_string(),
+            None => {
+                let candidate = candidate.to_string();
+                if self.defined_ids.contains(candidate.as_str()) {
+                    let id = format!("{}-{}", candidate, 1);
+                    self.map.insert(candidate.into(), 2);
+                    id
+                } else {
+                    candidate.to_string()
+                }
+            }
             Some(a) => {
                 let id = format!("{}-{}", candidate.as_ref(), *a);
                 *a += 1;
@@ -1985,7 +1982,6 @@ impl IdMap {
 
     pub(crate) fn clear(&mut self) {
         self.map.clear();
-        self.init_map();
         self.existing_footnotes = 0;
     }
 }

src/librustdoc/html/render/context.rs

@@ -87,12 +87,6 @@ impl ContextInfo {
     }
 }
 
-// `Context` is cloned a lot, so we don't want the size to grow unexpectedly.
-#[cfg(all(not(windows), target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(Context<'_>, 192);
-#[cfg(all(windows, target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(Context<'_>, 200);
-
 /// Shared mutable state used in [`Context`] and elsewhere.
 pub(crate) struct SharedContext<'tcx> {
     pub(crate) tcx: TyCtxt<'tcx>,