3 files changed, 8 insertions, 7 deletions

diff --git a/crates/ra_analysis/Cargo.toml b/crates/ra_analysis/Cargo.toml
index 4481e98d6..233f34e34 100644
--- a/crates/ra_analysis/Cargo.toml
+++ b/crates/ra_analysis/Cargo.toml
@@ -15,7 +15,8 @@ fst = "0.3.1"
 im = "12.0.0"
 ra_syntax = { path = "../ra_syntax" }
 ra_editor = { path = "../ra_editor" }
-salsa = "0.4.1"
+salsa = { git = "https://github.com/salsa-rs/salsa", rev = "20c9fbf" }
+rustc-hash = "1.0"
 
 [dev-dependencies]
 test_utils = { path = "../test_utils" }
diff --git a/crates/ra_analysis/src/db/mod.rs b/crates/ra_analysis/src/db/mod.rs
index c54d50252..c84bfa7a8 100644
--- a/crates/ra_analysis/src/db/mod.rs
+++ b/crates/ra_analysis/src/db/mod.rs
@@ -2,9 +2,9 @@ use std::{
     fmt,
     sync::Arc,
     hash::{Hash, Hasher},
-    collections::HashSet,
 };
 use salsa;
+use rustc_hash::FxHashSet;
 use ra_syntax::File;
 use ra_editor::{LineIndex};
 use crate::{
@@ -63,7 +63,7 @@ salsa::query_group! {
 
 #[derive(Default, Debug)]
 pub(crate) struct FileSet {
-    pub(crate) files: HashSet<FileId>,
+    pub(crate) files: FxHashSet<FileId>,
     pub(crate) resolver: FileResolverImp,
 }
 
diff --git a/crates/ra_analysis/src/roots.rs b/crates/ra_analysis/src/roots.rs
index 908f49b0a..692a07ccd 100644
--- a/crates/ra_analysis/src/roots.rs
+++ b/crates/ra_analysis/src/roots.rs
@@ -1,5 +1,4 @@
 use std::{
-    collections::{HashMap, HashSet},
     sync::Arc,
     panic,
 };
@@ -8,6 +7,7 @@ use parking_lot::RwLock;
 use once_cell::sync::OnceCell;
 use rayon::prelude::*;
 use salsa::Database;
+use rustc_hash::{FxHashMap, FxHashSet};
 use ra_editor::LineIndex;
 use ra_syntax::File;
 
@@ -40,8 +40,8 @@ impl WritableSourceRoot {
         file_resolver: Option<FileResolverImp>,
     ) -> WritableSourceRoot {
         let db = self.db.write();
-        let mut changed = HashSet::new();
-        let mut removed = HashSet::new();
+        let mut changed = FxHashSet::default();
+        let mut removed = FxHashSet::default();
         for (file_id, text) in changes {
             match text {
                 None => {
@@ -55,7 +55,7 @@ impl WritableSourceRoot {
             }
         }
         let file_set = db.file_set(());
-        let mut files: HashSet<FileId> = file_set
+        let mut files: FxHashSet<FileId> = file_set
             .files
             .clone();
         for file_id in removed {