From 076080f31d69f12d952466c4b5f1d2d3e50fabb8 Mon Sep 17 00:00:00 2001
From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com>
Date: Sun, 2 Jul 2023 15:42:17 +0200
Subject: [PATCH] use fxhash

---
 Cargo.lock  |  7 +++++++
 Cargo.toml  |  4 ++++
 src/main.rs | 11 +++++------
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 4d9aa18..275e54a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -83,6 +83,7 @@ dependencies = [
  "eyre",
  "object",
  "rustc-demangle",
+ "rustc-hash",
  "serde",
  "serde_json",
 ]
@@ -128,6 +129,12 @@ version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d626bb9dae77e28219937af045c257c28bfd3f69333c512553507f5f9798cb76"
 
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
 [[package]]
 name = "ruzstd"
 version = "0.3.1"
diff --git a/Cargo.toml b/Cargo.toml
index c7f3483..5b32a48 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,5 +9,9 @@ edition = "2021"
 eyre = "0.6.8"
 object = "0.31.1"
 rustc-demangle = { version = "0.1.23", features = ["std"] }
+rustc-hash = "1.1.0"
 serde = { version = "1.0.164", features = ["derive"] }
 serde_json = "1.0.99"
+
+[profile.release]
+debug = 1
diff --git a/src/main.rs b/src/main.rs
index 6387560..7d4c5e0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,7 @@
-use std::collections::HashMap;
-
 use eyre::{eyre, Context, ContextCompat, Result};
 use object::{Object, ObjectSection, ObjectSymbol};
 use serde::Serialize;
+use rustc_hash::FxHashMap;
 
 #[derive(serde::Serialize)]
 struct SerGroup {
@@ -17,7 +16,7 @@ fn main() -> Result<()> {
         .nth(1)
         .unwrap_or("./target/debug/my-binary-is-thicc-af".into());
 
-    let limit = 10;
+    let limit = 100;
 
     let data = std::fs::read(&path).wrap_err_with(|| format!("error opening `{path}`"))?;
     let object = object::File::parse(data.as_slice()).context("could not parse object file")?;
@@ -53,7 +52,7 @@ fn main() -> Result<()> {
     symbol_sizes.sort_by_key(|&(_, size)| size);
     symbol_sizes.reverse();
 
-    let mut root_groups = Groups(HashMap::new());
+    let mut root_groups = Groups(FxHashMap::default());
 
     for (sym, size) in symbol_sizes {
         let mut components = symbol_components(sym).with_context(|| sym.to_string())?;
@@ -78,7 +77,7 @@ fn main() -> Result<()> {
 }
 
 #[derive(Debug)]
-struct Groups(HashMap<String, Group>);
+struct Groups(FxHashMap<String, Group>);
 
 #[derive(Debug)]
 struct Group {
@@ -120,7 +119,7 @@ fn add_to_group(mut cur_groups: &mut Groups, components: Vec<String>, sym_size:
     for head in components {
         let grp = cur_groups.0.entry(head).or_insert(Group {
             weight: sym_size, // NOTE: This is a dummy value for everything but the innermost nesting.
-            children: Groups(HashMap::new()),
+            children: Groups(FxHashMap::default()),
         });
         cur_groups = &mut grp.children;
     }