beenull/ladybird
1
0
Fork 0
mirror of https://github.com/LadybirdBrowser/ladybird.git synced 2024-09-30 08:41:15 +00:00
Code Issues Actions 5 Packages Projects Releases Wiki Activity

LibJS: Make ObjectEnvironment::get_binding_value() faster in sloppy mode

Browse source 
We can combine HasProperty and Get into just Get in non-strict mode for
non-with object environments.
This commit is contained in:
Andreas Kling 2022-11-10 20:27:53 +01:00 committed by Linus Groh
parent 56abb01ee3
commit 12ceaf3790
Notes: sideshowbarker 2024-07-17 04:35:55 +09:00 
Author: https://github.com/awesomekling
Commit: https://github.com/SerenityOS/serenity/commit/12ceaf3790
Pull-request: https://github.com/SerenityOS/serenity/pull/16017
Reviewed-by: https://github.com/IdanHo
Reviewed-by: https://github.com/linusg ✅
1 changed files with 8 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
Userland/Libraries/LibJS/Runtime/ObjectEnvironment.cpp
View file

@ -127,6 +127,14 @@ ThrowCompletionOr<Value> ObjectEnvironment::get_binding_value(VM&, FlyString con
{
auto& vm = this->vm();
// OPTIMIZATION: For non-with environments in non-strict mode, we don't need the separate HasProperty check
// since Get will return undefined for missing properties anyway. So we take advantage of this
// to avoid doing both HasProperty and Get.
// We can't do this for with environments, since it would be observable (e.g via a Proxy)
// FIXME: We could combine HasProperty and Get in non-strict mode if Get would return a bit more failure information.
if (!m_with_environment && !strict)
return m_binding_object.get(name);
// 1. Let bindingObject be envRec.[[BindingObject]].
// 2. Let value be ? HasProperty(bindingObject, N).
auto value = TRY(m_binding_object.has_property(name));