Formal Methods and Theorem Provers
T-VEC is a formal method.
Formal methods are mathematically-based techniques for the specification, development and verification of software and hardware systems.
T-VEC (behind the scenes is a Theorem Prover) - per the wiki taxonomy
Level 2: Theorem provers may be used to undertake fully formal machine-checked proofs. This can be very expensive and is only practically worthwhile if the cost of mistakes is extremely high (e.g., in critical parts of microprocessor design).
IEC61508, ISO26262 have been started to recommend Formal Method.
DO-178B discusses formal methods in a "soft" tone, but DO-178C is discussing it more directly.