From Formal Semantics to Verified Slicing : A Modular Framework with Applications in Language Based Security

This book presents a modular framework for slicing in the proof assistant Isabelle/HOL which is based on abstract control flow graphs. Building on such abstract structures renders the correctness results language-independent. To prove that they hold for a specific language, it remains to instantiate the framework with this language, which requires a formal semantics of this language in Isabelle/HOL. We show that formal semantics even for sophisticated high-level languages are realizable

Knowledge Augmented Machine Learning with Applications in Autonomous Driving: A Survey

The existence of representative datasets is a prerequisite of many successful artificial intelligence and machine learning models. However, the subsequent application of these models often involves scenarios that are inadequately represented in the data used for training. The reasons for this are manifold and range from time and cost constraints to ethical considerations. As a consequence, the reliable use of these models, especially in safety-critical applications, is a huge challenge. Leveraging additional, already existing sources of knowledge is key to overcome the limitations of purely data-driven approaches, and eventually to increase the generalization capability of these models. Furthermore, predictions that conform with knowledge are crucial for making trustworthy and safe decisions even in underrepresented scenarios. This work provides an overview of existing techniques and methods in the literature that combine data-based models with existing knowledge. The identified approaches are structured according to the categories integration, extraction and conformity. Special attention is given to applications in the field of autonomous driving

From Formal Semantics to Verified Slicing : A Modular Framework with Applications in Language Based Security

This book presents a modular framework for slicing in the proof assistant Isabelle/HOL which is based on abstract control flow graphs. Building on such abstract structures renders the correctness results language-independent. To prove that they hold for a specific language, it remains to instantiate the framework with this language, which requires a formal semantics of this language in Isabelle/HOL. We show that formal semantics even for sophisticated high-level languages are realizable

Proving information flow noninterference by reusing a machinechecked correctness proof for slicing

We present a machine-checked correctness proof for information flow noninterference based on interprocedural slicing. It reuses a correctness proof of the context-sensitive interprocedural slicing algorithm of Horwitz, Reps, and Binkley. The underlying slicing framework is modular in the programming language used; by instantiating this framework the correctness proofs hold for the respective language, without reproving anything in the correctness proofs for slicing and noninterference. We present instantiations with two different languages to show the applicability of the framework, and thus a verified noninterference algorithm for these languages. The formalization and proofs are conducted in the proof assistant Isabelle/HOL.

An operational semantics and type safety proof for multiple inheritance in C++

We present an operational semantics and type safety proof for multiple inheritance in C++. The semantics models the behaviour of method calls, field accesses, and two forms of casts in C++ class hierarchies exactly, and the type safety proof was formalized and machine-checked in Isabelle/HOL. Our semantics enables one, for the first time, to understand the behaviour of operations on C++ class hierarchies without referring to implementation-level artifacts such as virtual function tables. Moreover, it can—as the semantics is executable—act as a reference for compilers, and it can form the basis for more advanced correctness proofs of, e.g., automated program transformations. The paper presents the semantics and type safety proof, and a discussion of the many subtleties that we encountered in modeling the intricate multiple inheritance model of C++