SpecChecker-ISA: a data sharing analyzer for interrupt-driven embedded software

Concurrency bugs are common in interrupt-driven programs, which are widely used in safety-critical areas. These bugs are often caused by incorrect data sharing among tasks and interrupts. Therefore, data sharing analysis is crucial to reason about the concurrency behaviours of interrupt-driven programs. Due to the variety of data access forms, existing tools suffer from both extensive false positives and false negatives while applying to interrupt-driven programs. This paper presents SpecChecker-ISA, a tool that provides sound and precise data sharing analysis for interrupt-driven embedded software. The tool uses a memory access model parameterized by numerical invariants, which are computed by abstract interpretation based value analysis, to describe data accesses of various kinds, and then uses numerical meet operations to obtain the final result of data sharing. Our experiments on 4 real-world aerospace embedded software show that SpecChecker-ISA can find all shared data accesses with few false positives, significantly outperforming other existing tools. The demo can be accessed at https://github.com/wangilson/specchecker-isa.