Private memory allocation analysis for safety-critical java

Safety-critical Java (SCJ) avoids garbage collection and uses a scope based memory model. This memory model is based on a restricted version of RTSJ [2] style scopes. The scopes form a clear hierarchy with different lifetimes. Therefore, references between objects in different scopes are only al- lowed from objects allocated in scopes with a shorter lifetime to objects allocated in scopes with a longer lifetime. To ensure memory safety, programmers are required to either manually annotate the application with complex annotations, rely on a runtime test of each reference assignment, or statically analyze all reference assignments and avoid run- time checks when all assignments are proven to be correct. A violation of the assignment rule at runtime leads to an unchecked exception. For safety-critical code that needs to be certified, runtime exceptions must be avoided and the absence of illegal reference assignments needs to be proven. In this paper we present a static program analysis tool that automates the proof that no illegal assignments occur