From 7af8efae2f8ab475653a219db9cbf78f1e22dbaa Mon Sep 17 00:00:00 2001
From: Shunsuke Shibayama <sbym1346@gmail.com>
Date: Thu, 3 Oct 2024 19:35:05 +0900
Subject: [PATCH] perf: use `ahash`

---
 Cargo.lock                   | 51 ++++++++++++++++++++++++++++++++++++
 crates/erg_common/Cargo.toml |  1 +
 crates/erg_common/fxhash.rs  |  6 +++--
 crates/erg_common/lib.rs     |  2 +-
 4 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index d2f4d460..55e97063 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -17,6 +17,19 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "512761e0bb2578dd7380c6baaa0f4ce03e84f95e960231d1dec8bf4d7d6e2627"
 
+[[package]]
+name = "ahash"
+version = "0.8.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e89da841a80418a9b391ebaea17f5c112ffaaa96f621d2c285b5174da76b9011"
+dependencies = [
+ "cfg-if",
+ "getrandom",
+ "once_cell",
+ "version_check",
+ "zerocopy",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.4.0"
@@ -130,6 +143,7 @@ dependencies = [
 name = "erg_common"
 version = "0.6.45"
 dependencies = [
+ "ahash",
  "backtrace-on-stack-overflow",
  "crossterm",
  "erg_proc_macros",
@@ -184,6 +198,17 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c4567c8db10ae91089c99af84c68c38da3ec2f087c3f82960bcdbf3656b6f4d7"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
 [[package]]
 name = "gimli"
 version = "0.31.0"
@@ -666,6 +691,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "version_check"
+version = "0.9.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
+
 [[package]]
 name = "w-boson"
 version = "0.1.0"
@@ -896,3 +927,23 @@ name = "windows_x86_64_msvc"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
+
+[[package]]
+name = "zerocopy"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
+dependencies = [
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.79",
+]
diff --git a/crates/erg_common/Cargo.toml b/crates/erg_common/Cargo.toml
index f9f61c7c..2433ac9e 100644
--- a/crates/erg_common/Cargo.toml
+++ b/crates/erg_common/Cargo.toml
@@ -37,6 +37,7 @@ w-boson = { version = "0.1.0", optional = true }
 crossterm = { optional = true, version = "0.25.0" }
 parking_lot = "0.12"
 thread_local = "1.1"
+ahash = "0.8"
 pyo3 = { workspace = true, optional = true }
 erg_proc_macros = { workspace = true }
 
diff --git a/crates/erg_common/fxhash.rs b/crates/erg_common/fxhash.rs
index a622e32f..95effd52 100644
--- a/crates/erg_common/fxhash.rs
+++ b/crates/erg_common/fxhash.rs
@@ -37,9 +37,11 @@ use core::mem::size_of;
 use core::ops::BitXor;
 use std::collections::{HashMap, HashSet};
 
+use ahash::AHasher;
+
 /// Type alias for a hashmap using the `fx` hash algorithm.
-pub type FxHashMap<K, V> = HashMap<K, V, BuildHasherDefault<FxHasher>>;
-pub type FxHashSet<T> = HashSet<T, BuildHasherDefault<FxHasher>>;
+pub type FxHashMap<K, V> = HashMap<K, V, BuildHasherDefault<AHasher>>;
+pub type FxHashSet<T> = HashSet<T, BuildHasherDefault<AHasher>>;
 
 /// A speedy hash algorithm for use within rustc. The hashmap in liballoc
 /// by default uses SipHash which isn't quite as speedy as we want. In the
diff --git a/crates/erg_common/lib.rs b/crates/erg_common/lib.rs
index 41ae32e3..af3acfb0 100644
--- a/crates/erg_common/lib.rs
+++ b/crates/erg_common/lib.rs
@@ -103,7 +103,7 @@ pub fn fmt_indent(s: String, depth: usize) -> String {
 
 /// If you want to get a hash consisting of multiple objects, pass it as a tuple or array
 pub fn get_hash<T: std::hash::Hash>(t: &T) -> usize {
-    let mut s = fxhash::FxHasher::default();
+    let mut s = ahash::AHasher::default();
     t.hash(&mut s);
     let res = std::hash::Hasher::finish(&s);
     if cfg!(target_pointer_width = "64") {