LibJS: Use a premade shape for normal function object prototypes

This avoids one shape allocation per function instantiation.
Author: https://github.com/awesomekling Commit: 8af5f25dd0 Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4119 Reviewed-by: https://github.com/gmta ✅
2025-09-07 18:17:23 +00:00 · 2025-03-25 19:16:11 +00:00 · 2025-03-25 19:16:11 +00:00 · 8af5f25dd0 · 2025-03-27 15:01:47 +00:00
commit 8af5f25dd0
parent dba1798de7
3 changed files with 14 additions and 2 deletions
--- a/Libraries/LibJS/Runtime/Intrinsics.h
+++ b/Libraries/LibJS/Runtime/Intrinsics.h
@ -28,6 +28,9 @@ public:
    [[nodiscard]] u32 iterator_result_object_value_offset() { return m_iterator_result_object_value_offset; }
    [[nodiscard]] u32 iterator_result_object_done_offset() { return m_iterator_result_object_done_offset; }

+    [[nodiscard]] GC::Ref<Shape> normal_function_prototype_shape() { return *m_normal_function_prototype_shape; }
+    [[nodiscard]] u32 normal_function_prototype_constructor_offset() const { return m_normal_function_prototype_constructor_offset; }
+
    // Not included in JS_ENUMERATE_NATIVE_OBJECTS due to missing distinct prototype
    GC::Ref<ProxyConstructor> proxy_constructor() { return *m_proxy_constructor; }

@ -133,6 +136,9 @@ private:
    u32 m_iterator_result_object_value_offset { 0 };
    u32 m_iterator_result_object_done_offset { 0 };

+    GC::Ptr<Shape> m_normal_function_prototype_shape;
+    u32 m_normal_function_prototype_constructor_offset { 0 };
+
    // Not included in JS_ENUMERATE_NATIVE_OBJECTS due to missing distinct prototype
    GC::Ptr<ProxyConstructor> m_proxy_constructor;