A Case Study in Automated A Case Study in Automated Verification - PowerPoint PPT Presentation

A Case Study in Automated A Case Study in Automated Verification Verification Jason Kirschenbaum Kirschenbaum, , Jason Heather Harton Harton and and Murali Murali Heather Sitaraman Sitaraman

Introduction Introduction Goal is to investigate automatic verification Goal is to investigate automatic verification of extensions to software components of extensions to software components – Including the development process Including the development process – Selection Sort Example Selection Sort Example – Simple Simple – – Theory Development Theory Development – – Specifications Specifications –

Focus of this Work Focus of this Work Full Behavioral Verification Full Behavioral Verification Language with Clean Semantics Language with Clean Semantics Modular Verification Modular Verification Generic Specification and Implementation Generic Specification and Implementation

Resolve Language Resolve Language Design by Contract Parameterized Code Design by Contract Parameterized Code Model Based Value Semantics Model Based Value Semantics Specifications Specifications Alias Avoidance Alias Avoidance Modular Reasoning Modular Reasoning Total Correctness Total Correctness Layered Layered Code Annotation Code Annotation Implementations Implementations Constructs Constructs

Vision of Development Process Vision of Development Process

Isabelle Isabelle Higher Order Higher Order Large Library of Verified Theories Large Library of Verified Theories Both Automated and User- -guided proof guided proof Both Automated and User methods methods

Selection Sort Specification Selection Sort Specification

Challenges Challenges Human Errors Human Errors – Specification bugs Specification bugs – Tool Weaknesses Tool Weaknesses – Lemmas involving permutation Lemmas involving permutation – – Proof is too long for Isabelle to find Proof is too long for Isabelle to find –

Challenge 1: Human Errors Challenge 1: Human Errors

Corrected Implementation Corrected Implementation

Challenge 2: Automation Challenge 2: Automation Verification Condition Proofs Issues Verification Condition Proofs Issues – Permutation Development Permutation Development – – Length of Proof Length of Proof –

First Type of Problem VC First Type of Problem VC

Second Type of Problem VC Second Type of Problem VC

Proposed Theory Development Proposed Theory Development

Updated Implementation Updated Implementation

Questions? Questions?