Efficient Runtime Assertion Checking for Properties over Mathematical Numbers

• Published in: Runtime Verification Vol. 12399; pp. 310 - 322
• Main Authors: Kosmatov, Nikolai, Maurica, Fonenantsoa, Signoles, Julien
• Format: Book Chapter
• Language: English
• Published: Switzerland Springer International Publishing AG 2020; Springer International Publishing
• Series: Lecture Notes in Computer Science
• Subjects: Numerical properties; Optimized code generation; Rational numbers; Runtime assertion checking; Typing
• ISBN: 3030605078; 9783030605070
• ISSN: 0302-9743; 1611-3349
• DOI: 10.1007/978-3-030-60508-7_17

Runtime assertion checking is the discipline of detecting at runtime violations of program properties written as formal code annotations. These properties often include numerical properties, which may rely on either (bounded) machine representations or (unbounded) mathematical numbers. The verification of the former is easier to implement and more efficient at runtime, while the latter are more expressive and often more adequate for writing specifications. This short paper explains how the runtime assertion checker E-ACSL reconciles both approaches by presenting a type system that allows the tool to generate efficient machine-number based code when it is safe to do so, while generating arbitrary-precision code when it is necessary. This type system and the code generator not only handle integers but also rational arithmetics. As far as we know, it is the first runtime verification tool that supports the verification of properties over rational numbers.