From d16fab5815f2f7b454c15d5aea36346c511e0eed Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Thu, 24 Nov 2022 15:38:52 +0100
Subject: [PATCH] LibJS: Avoid unnecessary SourceRange construction in
 parse_program()

This takes `test-js` runtime from 4.3 sec to 4.1 sec on my machine.
---
 Userland/Libraries/LibJS/AST.h      | 4 +++-
 Userland/Libraries/LibJS/Parser.cpp | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Userland/Libraries/LibJS/AST.h b/Userland/Libraries/LibJS/AST.h
index 47bd74a9273..f01f6c1917d 100644
--- a/Userland/Libraries/LibJS/AST.h
+++ b/Userland/Libraries/LibJS/AST.h
@@ -53,7 +53,9 @@ public:
     virtual Bytecode::CodeGenerationErrorOr<void> generate_bytecode(Bytecode::Generator&) const;
     virtual void dump(int indent) const;
 
-    SourceRange source_range() const;
+    [[nodiscard]] SourceRange source_range() const;
+
+    void set_end_offset(Badge<Parser>, u32 end_offset) { m_end_offset = end_offset; }
 
     String class_name() const;
 
diff --git a/Userland/Libraries/LibJS/Parser.cpp b/Userland/Libraries/LibJS/Parser.cpp
index ec5387b1fab..0baff40228c 100644
--- a/Userland/Libraries/LibJS/Parser.cpp
+++ b/Userland/Libraries/LibJS/Parser.cpp
@@ -497,7 +497,7 @@ NonnullRefPtr<Program> Parser::parse_program(bool starts_in_strict_mode)
     else
         parse_module(program);
 
-    program->source_range().end = position();
+    program->set_end_offset({}, position().offset);
     return program;
 }