From ad5465d6ce5ea17606a731bd03230e500deb9103 Mon Sep 17 00:00:00 2001
From: Wunkolo <Wunkolo@gmail.com>
Date: Fri, 24 Dec 2021 10:35:08 -0800
Subject: [PATCH] constant_pool: Use `tsl::robin_map` rather than
 `unordered_map`
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Finding a much more drastic improvement with `robin_map`.

`map`:
```
[master] % hyperfine -r 100 "./dynarmic_tests --durations yes"
Benchmark 1: ./dynarmic_tests --durations yes
  Time (mean ± σ):     567.0 ms ±   6.9 ms    [User: 513.1 ms, System: 53.2 ms]
  Range (min … max):   554.4 ms … 588.1 ms    100 runs
```

`unordered_map`:
```
[opt_const_pool] % hyperfine -r 100 "./dynarmic_tests --durations yes"
Benchmark 1: ./dynarmic_tests --durations yes
  Time (mean ± σ):     561.1 ms ±   4.5 ms    [User: 508.1 ms, System: 52.3 ms]
  Range (min … max):   552.6 ms … 574.2 ms    100 runs
```

`tsl::robin_map`:
```
[opt_const_pool] % hyperfine -r 100 "./dynarmic_tests --durations yes"
Benchmark 1: ./dynarmic_tests --durations yes
  Time (mean ± σ):     553.5 ms ±   5.6 ms    [User: 500.7 ms, System: 52.1 ms]
  Range (min … max):   545.7 ms … 569.3 ms    100 runs
```
---
 src/dynarmic/backend/x64/constant_pool.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/dynarmic/backend/x64/constant_pool.h b/src/dynarmic/backend/x64/constant_pool.h
index c7d11df7..04243993 100644
--- a/src/dynarmic/backend/x64/constant_pool.h
+++ b/src/dynarmic/backend/x64/constant_pool.h
@@ -6,9 +6,9 @@
 #pragma once
 
 #include <bit>
-#include <unordered_map>
 #include <utility>
 
+#include <tsl/robin_map.h>
 #include <xbyak/xbyak.h>
 
 #include "dynarmic/common/common_types.h"
@@ -36,7 +36,7 @@ private:
         }
     };
 
-    std::unordered_map<std::pair<u64, u64>, void*, ConstantHash> constant_info;
+    tsl::robin_map<std::pair<u64, u64>, void*, ConstantHash> constant_info;
 
     BlockOfCode& code;
     size_t pool_size;