Java Virtual-Machine Support for Portable Worst-Case Execution-Time Analysis

The current trend towards the usage of Java in real-time, supported by two specifications (Real-Time Java and RealTime Core extensions for the Java platform) requires adequate schedulability analysis, and consequently, worst case execution time (WCET) analysis techniques for the Java platform. This paper proposes a framework for providing portable WCET analysis for the Java platform. Portability means that the analysis is language and hardware independent. It is achieved by separating the WCET analysis process in three stages and by analysing the Java Byte Code, not the high-level source code, thus enabling the analysis of programs written in other languages (such as Ada and compiled for the Java virtual machine). The three stages are: a Java virtual machine platform dependent (low-level) analysis, a software dependent (high-level) analysis and an on-line integration step.