Performance Improvement of Kotlin Program in Consideration of JIT Compiler Optimization

Kotlin is a programming language that has high-level interoperability with Java. It was determined as the first-class language for Android application development in 2019 and is expected to increase its importance in client devices, such as smartphones and PCs, in the consumer electronics field. However, this is a newly emerging language and its performance has not been studied enough. In this paper, we focus on a simple program function, which is a for statement, and discuss its performance. First, we evaluate the performance of iteration with for statement written in Kotlin and Java and show that there is a significant performance difference. We then compare the Java virtual machine (JVM) bytecodes delivered from Kotlin and Java source codes and discuss the cause of this performance. Based on this comparison, we propose a method for improving the performance of an application written in Kotlin in Windows JVM with JIT (Just in time) compiler. We then show that our proposed method can improve the performance of processing a for statement of Kotlin.