Replace FnvHasher use with FxHasher.

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

Author: nnethercote

src/librustc/infer/mod.rs

@@ -39,7 +39,7 @@ use std::fmt;
 use syntax::ast;
 use errors::DiagnosticBuilder;
 use syntax_pos::{self, Span, DUMMY_SP};
-use util::nodemap::{FnvHashMap, FnvHashSet, NodeMap};
+use util::nodemap::{FxHashMap, FxHashSet, NodeMap};
 
 use self::combine::CombineFields;
 use self::higher_ranked::HrMatchResult;
@@ -134,7 +134,7 @@ pub struct InferCtxt<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
 
     // the set of predicates on which errors have been reported, to
     // avoid reporting the same error twice.
-    pub reported_trait_errors: RefCell<FnvHashSet<traits::TraitErrorKey<'tcx>>>,
+    pub reported_trait_errors: RefCell<FxHashSet<traits::TraitErrorKey<'tcx>>>,
 
     // Sadly, the behavior of projection varies a bit depending on the
     // stage of compilation. The specifics are given in the
@@ -170,7 +170,7 @@ pub struct InferCtxt<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
 
 /// A map returned by `skolemize_late_bound_regions()` indicating the skolemized
 /// region that each late-bound region was replaced with.
-pub type SkolemizationMap<'tcx> = FnvHashMap<ty::BoundRegion, &'tcx ty::Region>;
+pub type SkolemizationMap<'tcx> = FxHashMap<ty::BoundRegion, &'tcx ty::Region>;
 
 /// Why did we require that the two types be related?
 ///
@@ -492,7 +492,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'gcx> {
             selection_cache: traits::SelectionCache::new(),
             evaluation_cache: traits::EvaluationCache::new(),
             projection_cache: RefCell::new(traits::ProjectionCache::new()),
-            reported_trait_errors: RefCell::new(FnvHashSet()),
+            reported_trait_errors: RefCell::new(FxHashSet()),
             projection_mode: Reveal::NotSpecializable,
             tainted_by_errors_flag: Cell::new(false),
             err_count_on_creation: self.sess.err_count(),
@@ -531,7 +531,7 @@ impl<'a, 'gcx, 'tcx> InferCtxtBuilder<'a, 'gcx, 'tcx> {
             parameter_environment: param_env,
             selection_cache: traits::SelectionCache::new(),
             evaluation_cache: traits::EvaluationCache::new(),
-            reported_trait_errors: RefCell::new(FnvHashSet()),
+            reported_trait_errors: RefCell::new(FxHashSet()),
             projection_mode: projection_mode,
             tainted_by_errors_flag: Cell::new(false),
             err_count_on_creation: tcx.sess.err_count(),
@@ -1530,7 +1530,7 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
         span: Span,
         lbrct: LateBoundRegionConversionTime,
         value: &ty::Binder<T>)
-        -> (T, FnvHashMap<ty::BoundRegion, &'tcx ty::Region>)
+        -> (T, FxHashMap<ty::BoundRegion, &'tcx ty::Region>)
         where T : TypeFoldable<'tcx>
     {
         self.tcx.replace_late_bound_regions(

src/librustc/infer/region_inference/graphviz.rs

@@ -23,7 +23,7 @@ use middle::region::CodeExtent;
 use super::Constraint;
 use infer::SubregionOrigin;
 use infer::region_inference::RegionVarBindings;
-use util::nodemap::{FnvHashMap, FnvHashSet};
+use util::nodemap::{FxHashMap, FxHashSet};
 
 use std::borrow::Cow;
 use std::collections::hash_map::Entry::Vacant;
@@ -122,8 +122,8 @@ pub fn maybe_print_constraints_for<'a, 'gcx, 'tcx>(
 struct ConstraintGraph<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
     graph_name: String,
-    map: &'a FnvHashMap<Constraint<'tcx>, SubregionOrigin<'tcx>>,
-    node_ids: FnvHashMap<Node, usize>,
+    map: &'a FxHashMap<Constraint<'tcx>, SubregionOrigin<'tcx>>,
+    node_ids: FxHashMap<Node, usize>,
 }
 
 #[derive(Clone, Hash, PartialEq, Eq, Debug, Copy)]
@@ -145,7 +145,7 @@ impl<'a, 'gcx, 'tcx> ConstraintGraph<'a, 'gcx, 'tcx> {
            map: &'a ConstraintMap<'tcx>)
            -> ConstraintGraph<'a, 'gcx, 'tcx> {
         let mut i = 0;
-        let mut node_ids = FnvHashMap();
+        let mut node_ids = FxHashMap();
         {
             let mut add_node = |node| {
                 if let Vacant(e) = node_ids.entry(node) {
@@ -235,7 +235,7 @@ impl<'a, 'gcx, 'tcx> dot::GraphWalk<'a> for ConstraintGraph<'a, 'gcx, 'tcx> {
     type Node = Node;
     type Edge = Edge<'tcx>;
     fn nodes(&self) -> dot::Nodes<Node> {
-        let mut set = FnvHashSet();
+        let mut set = FxHashSet();
         for node in self.node_ids.keys() {
             set.insert(*node);
         }
@@ -261,7 +261,7 @@ impl<'a, 'gcx, 'tcx> dot::GraphWalk<'a> for ConstraintGraph<'a, 'gcx, 'tcx> {
     }
 }
 
-pub type ConstraintMap<'tcx> = FnvHashMap<Constraint<'tcx>, SubregionOrigin<'tcx>>;
+pub type ConstraintMap<'tcx> = FxHashMap<Constraint<'tcx>, SubregionOrigin<'tcx>>;
 
 fn dump_region_constraints_to<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
                                               map: &ConstraintMap<'tcx>,