Instrumenting Compiler Pipeline to Synthesise Traceable Runtime Memory Layouts in Mixed-critical Applications

Ensuring traceability between software code and its runtime memory is a required design measure in a number of application fields to achieve functional safety targets. For mixed-critical systems, where a code with different levels of criticality may coexist, this aspect is of particular importance. In the course of safety audits for example, this information may serve to build an evidence that safety-critical code/data is sufficiently isolated from non-critical parts. Unfortunately, addressing the evidence for every byte in memory is not supported by modern compilers. In this paper, we introduce a method where the compiler pipeline is instrumented to recover traceability links between the code and runtime memory. We qualify our proposal on a real-world industrial use case in which the C/C++ code is synthesised for ARM Cortex-M3 controllers. Our experimental results suggest that such an accurate traceability support may serve as a solid basis when analysing memories for mixed-critical applications.