Range Analyzer: An Automatic Tool for Arithmetic Overflow Detection in Model-Based Development

Airborne software is considered safety critical, since a defect in its execution can lead to economic consequences and the loss of human lives. In order to increase the correctness of an embedded software implementing system functions, compliance to the guidelines DO-178C and DO-331 is used to demonstrate that the software was developed according to requirements. Software verification is one of the processes to be performed during software development life cycle, analyzing the files generated during the development process looking for defects that could have been introduced. Absence of arithmetic overflow in one of the variables is a situation to be proved by the verification team because, when there is an overflow, the software calculations could not be trusted anymore. In order to detect this situation, some tools may be used to check source codes or to perform such analysis in model-based software design. The aim of this paper is to present an overview of the airborne software approval process, focusing on the model-based development, and to introduce a preliminary version of the development of the Range Analyzer, a tool with the capability to detect arithmetic overflow occurrences in a model within a SCADE Suite project. This proposed tool is an implementation of a range propagation algorithm, modified for the software analysis needs.