Assembler to C migration using the FermaT transformation system

The FermaT transformation system, based on research carried out over the last twelve years at Durham University and Software Migrations Ltd., is an industrial-strength formal transformation engine with many applications in program comprehension and language migration. This paper describes one application of the system: the migration of IBM 370 Assembler code to equivalent, maintainable C code. We present an example of using the tool to migrate a small, but complex, assembler module to C with no manual intervention required. We briefly discuss a mass migration exercise where 1,925 assembler modules were successfully migrated to C code

A parallel transformations framework for cluster environments.

In recent years program transformation technology has matured into a practical solution for many software reengineering and migration tasks. FermaT, an industrial strength program transformation system, has demonstrated that legacy systems can be successfully transformed into efficient and maintainable structured C or COBOL code. Its core, a transformation engine, is based on mathematically proven program transformations and ensures that transformed programs are semantically equivalent to its original state. Its engine facilitates a Wide Spectrum Language (WSL), with low-level as well as high-level constructs, to capture as much information as possible during transformation steps. FermaT’s methodology and technique lack in provision of concurrent migration and analysis. This provision is crucial if the transformation process is to be further automated. As the constraint based program migration theory has demonstrated, it is inefficient and time consuming, trying to satisfy the enormous computation of the generated transformation sequence search-space and its constraints. With the objective to solve the above problems and to extend the operating range of the FermaT transformation system, this thesis proposes a Parallel Transformations Framework which makes parallel transformations processing within the FermaT environment not only possible but also beneficial for its migration process. During a migration process, many thousands of program transformations have to be applied. For example a 1 million line of assembler to C migration takes over 21 hours to be processed on a single PC. Various approaches of search, prediction techniques and a constraint-based approach to address the presented issues already exist but they solve them unsatisfactorily. To remedy this situation, this dissertation proposes a framework to extend transformation processing systems with parallel processing capabilities. The parallel system can analyse specified parallel transformation tasks and produce appropriate parallel transformations processing outlines. To underpin an automated objective, a formal language is introduced. This language can be utilised to describe and outline parallel transformation tasks whereas parallel processing constraints underpin the parallel objective. This thesis addresses and explains how transformation processing steps can be automatically parallelised within a reengineering domain. It presents search and prediction tactics within this field. The decomposition and parallelisation of transformation sequence search-spaces is outlined. At the end, the presented work is evaluated on practical case studies, to demonstrate different parallel transformations processing techniques and conclusions are drawn

Constraint based program transformation theory

Software Migration Lt

Model driven software modernisation

Constant innovation of information technology and ever-changing market requirements relegate more and more existing software to legacy status. Generating software through reusing legacy systems has been a primary solution and software re-engineering has the potential to improve software productivity and quality across the entire software life cycle. The classical re-engineering technology starts at the level of program source code which is the most or only reliable information on a legacy system. The program specification derived from legacy source code will then facilitate the migration of legacy systems in the subsequent forward engineering steps. A recent research trend in re-engineering area carries this idea further and moves into model driven perspective that the specification is presented with models. The thesis focuses on engaging model technology to modernise legacy systems. A unified approach, REMOST (Re-Engineering through MOdel conStruction and Transformation), is proposed in the context of Model Driven Architecture (MDA). The theoretical foundation is the construction of a WSL-based Modelling Language, known as WML, which is an extension of WSL (Wide Spectrum Language). WML is defined to provide a spectrum of models for the system re-engineering, including Common Modelling Language (CML), Architecture Description Language (ADL) and Domain Specific Modelling Language (DSML). 9rtetaWML is designed for model transformation, providing query facilities, action primitives and metrics functions. A set of transformation rules are defined in 9rtetaWML to conduct system abstraction and refactoring. Model transformation for unifying WML and UML is also provided, which can bridge the legacy systems to MDA. The architecture and working flow of the REMOST approach are proposed and a prototype tool environment is developed for testing the approach. A number of case studies are used for experiments with the approach and the prototype tool, which show that the proposed approach is feasible and promising in its domain. Conclusion is drawn based on analysis and further research directions are also discussed

An agent-based service-oriented approach to evolving legacy software systems into a pervasive computing environment.

This thesis focuses on an Agent-Based Service-Oriented approach to evolving legacy system into a Pervasive Computing environment. The methodology consists of multiple phases: using reverse engineering techniques to comprehend and decompose legacy systems, employing XML and Web Services to transform and represent a legacy system as pervasive services, and integrating these pervasive services into pervasive computing environments with agent based integration technology. A legacy intelligent building system is used as a case study for experiments with the approach, which demonstrates that the proposed approach has the ability to evolve legacy systems into pervasive service environments seamlessly. Conclusion is drawn based on analysis and further research directions are also discussed

Provably Correct Derivation of Algorithms Using FermaT

The transformational programming method of algorithm derivation starts with a formal specification of the result to be achieved, plus some informal ideas as to what techniques will be used in the implementation. The formal specification is then transformed into an implementation, by means of correctness-preserving refinement and transformation steps, guided by the informal ideas. The transformation process will typically include the following stages: (1) Formal specification (2) Elaboration of the specification, (3) Divide and conquer to handle the general case (4) Recursion introduction, (5) Recursion removal, if an iterative solution is desired, (6) Optimisation, if required. At any stage in the process, sub-specifications can be extracted and transformed separately. The main difference between this approach and the invariant based programming approach (and similar stepwise refinement methods) is that loops can be introduced and manipulated while maintaining program correctness and with no need to derive loop invariants. Another difference is that at every stage in the process we are working with a correct program: there is never any need for a separate "verification" step. These factors help to ensure that the method is capable of scaling up to the development of large and complex software systems. The method is applied to the derivation of a complex linked list algorithm and produces code which is over twice as fast as the code written by Donald Knuth to solve the same problem

A program transformation step prediction based reengineering approach

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

A general algebra of business rules for heterogeneous systems

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Analytical solutions for selected types of differential equations: software support tool for students in technical fields

Cílem této práce bylo vytvořit počítačovou aplikaci s jednoduchým uživatelským rozhraním, určenou pro řešení vybraných typů diferenciálních rovnic, jejíž výstup není omezen na prosté zobrazení konečného výsledku, nýbrž zahrnuje i kompletní postup výpočtu, a díky tomu může sloužit jako podpůrná výuková pomůcka pro studenty vysokých škol.The aim of this thesis was to create a computer application with a simple user interface for solving selected types of differential equations, whose output is not limited to display a final result only, but also includes a complete calculation procedure and therefore can serve as a supportive teaching aid for university students.

Evolution of batch-oriented COBOL systems into object-oriented systems through unified modelling language.

Throughout the world, there are many legacy systems that fulfil critical business functions but often require new functionality to comply with new business rules or require redeployment to another platform. Legacy systems vary tremendously in size, functionality, type (such as batch-oriented or real-time), programming language source code, and many other factors. Furthermore, many of these legacy systems have missing or obsolete documentation which makes it difficult for developers to re-develop the system to meet any new functionality. Moreover, the high cost of whole scale redevelopment and high switchover costs preclude any replacement systems for these legacy systems. Reengineering is often proposed as a solution to this dilemma of high re-development and switchover costs. However, reengineering a legacy system often entails restructuring and re-documenting a system. Once these restructuring and re-documentation processes have been completed, the developers are better able to redevelop the parts of the systems that are required to meet any new functionality. This thesis introduces a number of methods to restructure a procedurally-structured, batch-oriented COBOL system into an object-oriented, event-driven system through the use of an intermediate mathematical language, the Wide Spectrum Language (WSL), using system source code as the only documentation artefact. This restructuring process is accomplished through the application of several algorithms of object identification, independent task evaluation, and event identification that are provided in the thesis. Once these transformations are complete, method(s) are specified to extract a series of UML diagrams from this code in order to provide documentation of this system. This thesis outlines which of the UML diagrams, as specified in the UML Specifications version 1.5, can be extracted using the specified methods and under what conditions this extraction, using system source code only, can occur in a batch-oriented system. These UML diagrams are first expressed through a WSL-UML notation; a notation which follows the semantics and structure of UML Specifications version 1.5 in order to ensure compatibility with UML but is written as an extension of WSL in order to enable WSL to represent abstract modelling concepts and diagrams. This WSL-UML notation is then imported into a visual UML diagramming tool for the generation of UML diagrams to represent this system. The variety of legacy systems precludes any universal approach to reengineering. Even if a legacy system shares a common programming language, such as COBOL, the large number of COBOL constructs and the huge number of possible dialects prevents any universal translator of the original program code to another. It is hoped that by focusing on one particular type of legacy system with constraints, in this case a batch-oriented COBOL system with its source code its only surviving artefact, and by providing validated algorithms to restructure and re-document these legacy systems in the Unified Modelling Language, an industry system modelling standard, and by determining which of these Unified Modelling Language can be extracted practically from such a system, some of the parameters and uncertainties, such as program understanding of an undocumented system, in reengineering this type of system can be reduced