From 4e2845847b47bfb2a83d4a6ee2cb97d5e400582b Mon Sep 17 00:00:00 2001
From: Ali Mohammad Pur <ali.mpfard@gmail.com>
Date: Fri, 1 Aug 2025 18:31:39 +0200
Subject: [PATCH] LibJS: Add a fast-path to <Int32>.to_uint8()

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---
 Libraries/LibJS/Runtime/Value.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Libraries/LibJS/Runtime/Value.cpp b/Libraries/LibJS/Runtime/Value.cpp
index f7d7387f78f..681c39853ba 100644
--- a/Libraries/LibJS/Runtime/Value.cpp
+++ b/Libraries/LibJS/Runtime/Value.cpp
@@ -1050,6 +1050,11 @@ ThrowCompletionOr<i8> Value::to_i8(VM& vm) const
 // 7.1.11 ToUint8 ( argument ), https://tc39.es/ecma262/#sec-touint8
 ThrowCompletionOr<u8> Value::to_u8(VM& vm) const
 {
+    // OPTIMIZATION: Fast path for the common case of an int32.
+    if (is_int32()) {
+        return static_cast<u8>(as_i32() & NumericLimits<u8>::max());
+    }
+
     // 1. Let number be ? ToNumber(argument).
     double number = TRY(to_number(vm)).as_double();