Rollup merge of #80047 - jyn514:more-symbols, r=GuillaumeGomez

Use more symbols in rustdoc

Builds on #80044 and should not be merged before.

I want to test if this is actually faster before merging it, there was a lot of `to_string()` calls so I'm not sure it will actually help. That means I have to wait for 80044 to get merged before running perf.

r? `@ghost`

Author: GuillaumeGomez

src/librustdoc/clean/mod.rs

@@ -207,7 +207,7 @@ impl Clean<ExternalCrate> for CrateNum {
         };
 
         ExternalCrate {
-            name: cx.tcx.crate_name(*self).to_string(),
+            name: cx.tcx.crate_name(*self),
             src: krate_src,
             attrs: cx.tcx.get_attrs(root).clean(cx),
             primitives,

src/librustdoc/clean/types.rs

@@ -51,7 +51,7 @@ thread_local!(crate static MAX_DEF_ID: RefCell<FxHashMap<CrateNum, DefId>> = Def
 
 #[derive(Clone, Debug)]
 crate struct Crate {
-    crate name: String,
+    crate name: Symbol,
     crate version: Option<String>,
     crate src: FileName,
     crate module: Option<Item>,
@@ -66,7 +66,7 @@ crate struct Crate {
 
 #[derive(Clone, Debug)]
 crate struct ExternalCrate {
-    crate name: String,
+    crate name: Symbol,
     crate src: FileName,
     crate attrs: Attributes,
     crate primitives: Vec<(DefId, PrimitiveType)>,

src/librustdoc/formats/cache.rs

@@ -8,6 +8,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
 use rustc_middle::middle::privacy::AccessLevels;
 use rustc_span::source_map::FileName;
+use rustc_span::Symbol;
 
 use crate::clean::{self, GetDefId};
 use crate::config::RenderInfo;
@@ -74,7 +75,7 @@ crate struct Cache {
     crate implementors: FxHashMap<DefId, Vec<Impl>>,
 
     /// Cache of where external crate documentation can be found.
-    crate extern_locations: FxHashMap<CrateNum, (String, PathBuf, ExternalLocation)>,
+    crate extern_locations: FxHashMap<CrateNum, (Symbol, PathBuf, ExternalLocation)>,
 
     /// Cache of where documentation for primitives can be found.
     crate primitive_locations: FxHashMap<clean::PrimitiveType, DefId>,
@@ -173,10 +174,10 @@ impl Cache {
                 },
                 _ => PathBuf::new(),
             };
-            let extern_url = extern_html_root_urls.get(&e.name).map(|u| &**u);
+            let extern_url = extern_html_root_urls.get(&*e.name.as_str()).map(|u| &**u);
             cache
                 .extern_locations
-                .insert(n, (e.name.clone(), src_root, extern_location(e, extern_url, &dst)));
+                .insert(n, (e.name, src_root, extern_location(e, extern_url, &dst)));
 
             let did = DefId { krate: n, index: CRATE_DEF_INDEX };
             cache.external_paths.insert(did, (vec![e.name.to_string()], ItemType::Module));
@@ -195,7 +196,7 @@ impl Cache {
             cache.primitive_locations.insert(prim, def_id);
         }
 
-        cache.stack.push(krate.name.clone());
+        cache.stack.push(krate.name.to_string());
         krate = cache.fold_crate(krate);
 
         for (trait_did, dids, impl_) in cache.orphan_trait_impls.drain(..) {
@@ -340,7 +341,7 @@ impl DocFolder for Cache {
 
         // Keep track of the fully qualified path for this item.
         let pushed = match item.name {
-            Some(ref n) if !n.is_empty() => {
+            Some(n) if !n.is_empty() => {
                 self.stack.push(n.to_string());
                 true
             }

src/librustdoc/formats/renderer.rs

@@ -3,7 +3,6 @@ use std::sync::Arc;
 use rustc_data_structures::sync::Lrc;
 use rustc_session::Session;
 use rustc_span::edition::Edition;
-use rustc_span::Symbol;
 
 use crate::clean;
 use crate::config::{RenderInfo, RenderOptions};
@@ -76,7 +75,7 @@ crate fn run_format<T: FormatRenderer>(
         None => return Ok(()),
     };
 
-    item.name = Some(Symbol::intern(&krate.name));
+    item.name = Some(krate.name);
 
     // Render the crate documentation
     let mut work = vec![(format_renderer.clone(), item)];

src/librustdoc/html/render/cache.rs

@@ -31,7 +31,7 @@ crate fn extern_location(
 ) -> ExternalLocation {
     use ExternalLocation::*;
     // See if there's documentation generated into the local directory
-    let local_location = dst.join(&e.name);
+    let local_location = dst.join(&*e.name.as_str());
     if local_location.is_dir() {
         return Local;
     }

src/librustdoc/html/render/mod.rs

@@ -418,14 +418,15 @@ impl FormatRenderer for Context {
         // If user passed in `--playground-url` arg, we fill in crate name here
         let mut playground = None;
         if let Some(url) = playground_url {
-            playground = Some(markdown::Playground { crate_name: Some(krate.name.clone()), url });
+            playground =
+                Some(markdown::Playground { crate_name: Some(krate.name.to_string()), url });
         }
         let mut layout = layout::Layout {
             logo: String::new(),
             favicon: String::new(),
             external_html,
             default_settings,
-            krate: krate.name.clone(),
+            krate: krate.name.to_string(),
             css_file_extension: extension_css,
             generate_search_filter,
         };
@@ -445,7 +446,7 @@ impl FormatRenderer for Context {
                     }
                     (sym::html_playground_url, Some(s)) => {
                         playground = Some(markdown::Playground {
-                            crate_name: Some(krate.name.clone()),
+                            crate_name: Some(krate.name.to_string()),
                             url: s.to_string(),
                         });
                     }
@@ -530,7 +531,7 @@ impl FormatRenderer for Context {
     }
 
     fn after_krate(&mut self, krate: &clean::Crate, cache: &Cache) -> Result<(), Error> {
-        let final_file = self.dst.join(&krate.name).join("all.html");
+        let final_file = self.dst.join(&*krate.name.as_str()).join("all.html");
         let settings_file = self.dst.join("settings.html");
         let crate_name = krate.name.clone();
 
@@ -1019,7 +1020,8 @@ themePicker.onblur = handleThemeButtonsBlur;
         }
 
         let dst = cx.dst.join(&format!("source-files{}.js", cx.shared.resource_suffix));
-        let (mut all_sources, _krates) = try_err!(collect(&dst, &krate.name, "sourcesIndex"), &dst);
+        let (mut all_sources, _krates) =
+            try_err!(collect(&dst, &krate.name.as_str(), "sourcesIndex"), &dst);
         all_sources.push(format!(
             "sourcesIndex[\"{}\"] = {};",
             &krate.name,
@@ -1035,7 +1037,7 @@ themePicker.onblur = handleThemeButtonsBlur;
 
     // Update the search index
     let dst = cx.dst.join(&format!("search-index{}.js", cx.shared.resource_suffix));
-    let (mut all_indexes, mut krates) = try_err!(collect_json(&dst, &krate.name), &dst);
+    let (mut all_indexes, mut krates) = try_err!(collect_json(&dst, &krate.name.as_str()), &dst);
     all_indexes.push(search_index);
 
     // Sort the indexes by crate so the file will be generated identically even
@@ -1070,7 +1072,7 @@ themePicker.onblur = handleThemeButtonsBlur;
                 extra_scripts: &[],
                 static_extra_scripts: &[],
             };
-            krates.push(krate.name.clone());
+            krates.push(krate.name.to_string());
             krates.sort();
             krates.dedup();
 
@@ -1162,7 +1164,7 @@ themePicker.onblur = handleThemeButtonsBlur;
         mydst.push(&format!("{}.{}.js", remote_item_type, remote_path[remote_path.len() - 1]));
 
         let (mut all_implementors, _) =
-            try_err!(collect(&mydst, &krate.name, "implementors"), &mydst);
+            try_err!(collect(&mydst, &krate.name.as_str(), "implementors"), &mydst);
         all_implementors.push(implementors);
         // Sort the implementors by crate so the file will be generated
         // identically even with rustdoc running in parallel.
@@ -1648,16 +1650,17 @@ impl Context {
         };
         let file = &file;
 
+        let symbol;
         let (krate, path) = if cnum == LOCAL_CRATE {
             if let Some(path) = self.shared.local_sources.get(file) {
-                (&self.shared.layout.krate, path)
+                (self.shared.layout.krate.as_str(), path)
             } else {
                 return None;
             }
         } else {
             let (krate, src_root) = match *cache.extern_locations.get(&cnum)? {
-                (ref name, ref src, ExternalLocation::Local) => (name, src),
-                (ref name, ref src, ExternalLocation::Remote(ref s)) => {
+                (name, ref src, ExternalLocation::Local) => (name, src),
+                (name, ref src, ExternalLocation::Remote(ref s)) => {
                     root = s.to_string();
                     (name, src)
                 }
@@ -1671,7 +1674,8 @@ impl Context {
             let mut fname = file.file_name().expect("source has no filename").to_os_string();
             fname.push(".html");
             path.push_str(&fname.to_string_lossy());
-            (krate, &path)
+            symbol = krate.as_str();
+            (&*symbol, &path)
         };
 
         let loline = item.source.lo(self.sess()).line;

src/librustdoc/html/sources.rs

@@ -19,7 +19,7 @@ crate fn render(
     krate: clean::Crate,
 ) -> Result<clean::Crate, Error> {
     info!("emitting source files");
-    let dst = dst.join("src").join(&krate.name);
+    let dst = dst.join("src").join(&*krate.name.as_str());
     scx.ensure_dir(&dst)?;
     let mut folder = SourceCollector { dst, scx };
     Ok(folder.fold_crate(krate))

src/librustdoc/json/mod.rs

@@ -223,7 +223,7 @@ impl FormatRenderer for JsonRenderer {
                     (
                         k.as_u32(),
                         types::ExternalCrate {
-                            name: v.0.clone(),
+                            name: v.0.to_string(),
                             html_root_url: match &v.2 {
                                 ExternalLocation::Remote(s) => Some(s.clone()),
                                 _ => None,

src/librustdoc/lib.rs

@@ -519,17 +519,12 @@ fn main_options(options: config::Options) -> MainResult {
     // compiler all the way through the analysis passes. The rustdoc output is
     // then generated from the cleaned AST of the crate. This runs all the
     // plug/cleaning passes.
-    let crate_name = options.crate_name.clone();
     let crate_version = options.crate_version.clone();
     let output_format = options.output_format;
     let (mut krate, renderinfo, renderopts, sess) = core::run_core(options);
 
     info!("finished with rustc");
 
-    if let Some(name) = crate_name {
-        krate.name = name
-    }
-
     krate.version = crate_version;
 
     if show_coverage {