From d8e8293b7e188383b95ca97e88db82e2d7a9bed9 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sat, 2 Mar 2024 11:41:31 +0100
Subject: [PATCH] LibWeb: Add PercentageOr<Length>::to_px() fast path for
 absolute lengths

We can avoid round-tripping through a temporary Length in the simple
case here.
---
 Userland/Libraries/LibWeb/CSS/PercentageOr.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Userland/Libraries/LibWeb/CSS/PercentageOr.h b/Userland/Libraries/LibWeb/CSS/PercentageOr.h
index 77046ac22c6..a6cf565e560 100644
--- a/Userland/Libraries/LibWeb/CSS/PercentageOr.h
+++ b/Userland/Libraries/LibWeb/CSS/PercentageOr.h
@@ -97,6 +97,12 @@ public:
 
     CSSPixels to_px(Layout::Node const& layout_node, CSSPixels reference_value) const
     {
+        if constexpr (IsSame<T, Length>) {
+            if (auto const* length = m_value.template get_pointer<Length>()) {
+                if (length->is_absolute())
+                    return length->absolute_length_to_px();
+            }
+        }
         return resolved(layout_node, reference_value).to_px(layout_node);
     }