From 361a1b54d75de9fb9b9e04c82f87b58d37f4e2bc Mon Sep 17 00:00:00 2001
From: Sergey Bugaev <bugaevc@serenityos.org>
Date: Thu, 30 Apr 2020 11:50:26 +0300
Subject: [PATCH] AK: Add Checked::addition_would_overflow()

And switch the two-argument version of Checked::multiplication_would_overflow()
to use __builtin_mul_overflow_p(). This helps GCC optimize the code better.
---
 AK/Checked.h | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/AK/Checked.h b/AK/Checked.h
index 9514a8fb9d..ac98519678 100644
--- a/AK/Checked.h
+++ b/AK/Checked.h
@@ -234,13 +234,16 @@ public:
         return *this;
     }
 
+    template<typename U, typename V>
+    static bool addition_would_overflow(U u, V v)
+    {
+        return __builtin_add_overflow_p(u, v, (T)0);
+    }
+
     template<typename U, typename V, typename X>
     static bool multiplication_would_overflow(U u, V v)
     {
-        Checked checked;
-        checked = u;
-        checked *= v;
-        return checked.has_overflow();
+        return __builtin_mul_overflow_p(u, v, (T)0);
     }
 
     template<typename U, typename V, typename X>