From 7ebe8c20e80bcb09ec29082a8e5ebfd40daaf03e Mon Sep 17 00:00:00 2001
From: overlookmotel <557937+overlookmotel@users.noreply.github.com>
Date: Thu, 28 Nov 2024 11:39:14 +0000
Subject: [PATCH] perf(transformer): use `FxDashMap` for browser query cache
 (#7521)

Use `FxDashMap` instead of plain `DashMap` for browser query cache.

Inspired by https://github.com/rolldown/rolldown/pull/2971.
---
 crates/oxc_transformer/src/options/browserslist_query.rs | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/crates/oxc_transformer/src/options/browserslist_query.rs b/crates/oxc_transformer/src/options/browserslist_query.rs
index 84acb91de..1f988b290 100644
--- a/crates/oxc_transformer/src/options/browserslist_query.rs
+++ b/crates/oxc_transformer/src/options/browserslist_query.rs
@@ -1,10 +1,13 @@
 use std::sync::OnceLock;
 
 use dashmap::DashMap;
+use rustc_hash::FxBuildHasher;
 use serde::Deserialize;
 
 use super::EngineTargets;
 
+type FxDashMap<K, V> = DashMap<K, V, FxBuildHasher>;
+
 #[derive(Debug, Clone, Deserialize, Eq, PartialEq, PartialOrd, Ord, Hash)]
 #[serde(untagged)]
 pub enum BrowserslistQuery {
@@ -12,9 +15,9 @@ pub enum BrowserslistQuery {
     Multiple(Vec<String>),
 }
 
-fn cache() -> &'static DashMap<BrowserslistQuery, EngineTargets> {
-    static CACHE: OnceLock<DashMap<BrowserslistQuery, EngineTargets>> = OnceLock::new();
-    CACHE.get_or_init(DashMap::new)
+fn cache() -> &'static FxDashMap<BrowserslistQuery, EngineTargets> {
+    static CACHE: OnceLock<FxDashMap<BrowserslistQuery, EngineTargets>> = OnceLock::new();
+    CACHE.get_or_init(FxDashMap::default)
 }
 
 impl BrowserslistQuery {