Replace FnvHasher use with FxHasher.

This speeds up compilation by 3--6% across most of rustc-benchmarks.

src/librustdoc/html/render.rs

@@ -59,7 +59,7 @@ use rustc::hir::def_id::{CrateNum, CRATE_DEF_INDEX, DefId, LOCAL_CRATE};
 use rustc::middle::privacy::AccessLevels;
 use rustc::middle::stability;
 use rustc::hir;
-use rustc::util::nodemap::{FnvHashMap, FnvHashSet};
+use rustc::util::nodemap::{FxHashMap, FxHashSet};
 use rustc_data_structures::flock;
 
 use clean::{self, Attributes, GetDefId, SelfTy, Mutability};
@@ -111,9 +111,9 @@ pub struct SharedContext {
     /// `true`.
     pub include_sources: bool,
     /// The local file sources we've emitted and their respective url-paths.
-    pub local_sources: FnvHashMap<PathBuf, String>,
+    pub local_sources: FxHashMap<PathBuf, String>,
     /// All the passes that were run on this crate.
-    pub passes: FnvHashSet<String>,
+    pub passes: FxHashSet<String>,
     /// The base-URL of the issue tracker for when an item has been tagged with
     /// an issue number.
     pub issue_tracker_base_url: Option<String>,
@@ -208,7 +208,7 @@ pub struct Cache {
     /// Mapping of typaram ids to the name of the type parameter. This is used
     /// when pretty-printing a type (so pretty printing doesn't have to
     /// painfully maintain a context like this)
-    pub typarams: FnvHashMap<DefId, String>,
+    pub typarams: FxHashMap<DefId, String>,
 
     /// Maps a type id to all known implementations for that type. This is only
     /// recognized for intra-crate `ResolvedPath` types, and is used to print
@@ -216,35 +216,35 @@ pub struct Cache {
     ///
     /// The values of the map are a list of implementations and documentation
     /// found on that implementation.
-    pub impls: FnvHashMap<DefId, Vec<Impl>>,
+    pub impls: FxHashMap<DefId, Vec<Impl>>,
 
     /// Maintains a mapping of local crate node ids to the fully qualified name
     /// and "short type description" of that node. This is used when generating
     /// URLs when a type is being linked to. External paths are not located in
     /// this map because the `External` type itself has all the information
     /// necessary.
-    pub paths: FnvHashMap<DefId, (Vec<String>, ItemType)>,
+    pub paths: FxHashMap<DefId, (Vec<String>, ItemType)>,
 
     /// Similar to `paths`, but only holds external paths. This is only used for
     /// generating explicit hyperlinks to other crates.
-    pub external_paths: FnvHashMap<DefId, (Vec<String>, ItemType)>,
+    pub external_paths: FxHashMap<DefId, (Vec<String>, ItemType)>,
 
     /// This map contains information about all known traits of this crate.
     /// Implementations of a crate should inherit the documentation of the
     /// parent trait if no extra documentation is specified, and default methods
     /// should show up in documentation about trait implementations.
-    pub traits: FnvHashMap<DefId, clean::Trait>,
+    pub traits: FxHashMap<DefId, clean::Trait>,
 
     /// When rendering traits, it's often useful to be able to list all
     /// implementors of the trait, and this mapping is exactly, that: a mapping
     /// of trait ids to the list of known implementors of the trait
-    pub implementors: FnvHashMap<DefId, Vec<Implementor>>,
+    pub implementors: FxHashMap<DefId, Vec<Implementor>>,
 
     /// Cache of where external crate documentation can be found.
-    pub extern_locations: FnvHashMap<CrateNum, (String, ExternalLocation)>,
+    pub extern_locations: FxHashMap<CrateNum, (String, ExternalLocation)>,
 
     /// Cache of where documentation for primitives can be found.
-    pub primitive_locations: FnvHashMap<clean::PrimitiveType, CrateNum>,
+    pub primitive_locations: FxHashMap<clean::PrimitiveType, CrateNum>,
 
     // Note that external items for which `doc(hidden)` applies to are shown as
     // non-reachable while local items aren't. This is because we're reusing
@@ -257,7 +257,7 @@ pub struct Cache {
     parent_stack: Vec<DefId>,
     parent_is_trait_impl: bool,
     search_index: Vec<IndexItem>,
-    seen_modules: FnvHashSet<DefId>,
+    seen_modules: FxHashSet<DefId>,
     seen_mod: bool,
     stripped_mod: bool,
     deref_trait_did: Option<DefId>,
@@ -275,9 +275,9 @@ pub struct Cache {
 /// Later on moved into `CACHE_KEY`.
 #[derive(Default)]
 pub struct RenderInfo {
-    pub inlined: FnvHashSet<DefId>,
+    pub inlined: FxHashSet<DefId>,
     pub external_paths: ::core::ExternalPaths,
-    pub external_typarams: FnvHashMap<DefId, String>,
+    pub external_typarams: FxHashMap<DefId, String>,
     pub deref_trait_did: Option<DefId>,
     pub deref_mut_trait_did: Option<DefId>,
 }
@@ -376,10 +376,10 @@ impl ToJson for IndexItemFunctionType {
 thread_local!(static CACHE_KEY: RefCell<Arc<Cache>> = Default::default());
 thread_local!(pub static CURRENT_LOCATION_KEY: RefCell<Vec<String>> =
                     RefCell::new(Vec::new()));
-thread_local!(static USED_ID_MAP: RefCell<FnvHashMap<String, usize>> =
+thread_local!(static USED_ID_MAP: RefCell<FxHashMap<String, usize>> =
                     RefCell::new(init_ids()));
 
-fn init_ids() -> FnvHashMap<String, usize> {
+fn init_ids() -> FxHashMap<String, usize> {
     [
      "main",
      "search",
@@ -406,7 +406,7 @@ pub fn reset_ids(embedded: bool) {
         *s.borrow_mut() = if embedded {
             init_ids()
         } else {
-            FnvHashMap()
+            FxHashMap()
         };
     });
 }
@@ -431,7 +431,7 @@ pub fn derive_id(candidate: String) -> String {
 pub fn run(mut krate: clean::Crate,
            external_html: &ExternalHtml,
            dst: PathBuf,
-           passes: FnvHashSet<String>,
+           passes: FxHashSet<String>,
            css_file_extension: Option<PathBuf>,
            renderinfo: RenderInfo) -> Result<(), Error> {
     let src_root = match krate.src.parent() {
@@ -442,7 +442,7 @@ pub fn run(mut krate: clean::Crate,
         src_root: src_root,
         passes: passes,
         include_sources: true,
-        local_sources: FnvHashMap(),
+        local_sources: FxHashMap(),
         issue_tracker_base_url: None,
         layout: layout::Layout {
             logo: "".to_string(),
@@ -510,22 +510,22 @@ pub fn run(mut krate: clean::Crate,
         .collect();
 
     let mut cache = Cache {
-        impls: FnvHashMap(),
+        impls: FxHashMap(),
         external_paths: external_paths,
-        paths: FnvHashMap(),
-        implementors: FnvHashMap(),
+        paths: FxHashMap(),
+        implementors: FxHashMap(),
         stack: Vec::new(),
         parent_stack: Vec::new(),
         search_index: Vec::new(),
         parent_is_trait_impl: false,
-        extern_locations: FnvHashMap(),
-        primitive_locations: FnvHashMap(),
-        seen_modules: FnvHashSet(),
+        extern_locations: FxHashMap(),
+        primitive_locations: FxHashMap(),
+        seen_modules: FxHashSet(),
         seen_mod: false,
         stripped_mod: false,
         access_levels: krate.access_levels.clone(),
         orphan_impl_items: Vec::new(),
-        traits: mem::replace(&mut krate.external_traits, FnvHashMap()),
+        traits: mem::replace(&mut krate.external_traits, FxHashMap()),
         deref_trait_did: deref_trait_did,
         deref_mut_trait_did: deref_mut_trait_did,
         typarams: external_typarams,
@@ -572,7 +572,7 @@ pub fn run(mut krate: clean::Crate,
 
 /// Build the search index from the collected metadata
 fn build_index(krate: &clean::Crate, cache: &mut Cache) -> String {
-    let mut nodeid_to_pathid = FnvHashMap();
+    let mut nodeid_to_pathid = FxHashMap();
     let mut crate_items = Vec::with_capacity(cache.search_index.len());
     let mut crate_paths = Vec::<Json>::new();
 
@@ -2618,7 +2618,7 @@ fn render_union(w: &mut fmt::Formatter, it: &clean::Item,
 #[derive(Copy, Clone)]
 enum AssocItemLink<'a> {
     Anchor(Option<&'a str>),
-    GotoSource(DefId, &'a FnvHashSet<String>),
+    GotoSource(DefId, &'a FxHashSet<String>),
 }
 
 impl<'a> AssocItemLink<'a> {