1. CROSSmeeting UM, Fev. 2010 1 T5: Slicing Techniques Applied to OSS Pedro Rangel Henriques Daniela da Cruz Dep. de Informática/CCTC, Universidade do Minho, Braga-Portugal UM Fevereiro de 2010

2. CROSSmeeting UM, Fev. 2010 2Context CROSS (an infrastructure for Certification and Re-engineering of Open-Source Sw) ; Code Analysis for software comprehension (quality assessment, re-use, re-engineering, transformation)

3. CROSSmeeting UM, Fev. 2010 3Motivation To contribute to the portfolio of analysis tools – that will be made available through the OSS Certification Portal (task T7) improving Code Analysis via Slicing Techniques

4. CROSSmeeting UM, Fev. 2010 4 Code Analysis Code Analysis is concerned with the extraction of data from Programs the storage of information, and the visualization of knowledge SWSystem, aiming at its comprehension.

5. CROSSmeeting UM, Fev. 2010 5 Code Analysis To face the growing complexity of software systems, a promising approach for CA is the restriction of the analysis to a program slice.

6. CROSSmeeting UM, Fev. 2010 6 Our main Proposal Semantic slicing applied intra and inter program components increases component understanding/reusing Semantic slicing is based on contracts (pre, post-conditions and invariants)

7. CROSSmeeting UM, Fev. 2010 7Objectives We planned 5 subtasks 1. Test-bed. 2. Semantic Slicing 3. Labeled Control Graph 4. Slicing Specific Software Facets 5. Dynamic slicing techniques

8. CROSSmeeting UM, Fev. 2010 8 Objectives – substask1 Test-bed. Development of a platform (web environment) to support the pragmatic validation of the semantic slicing variants under study.

9. CROSSmeeting UM, Fev. 2010 9 Objectives – substask2 Development of new slicing techniques for annotated programs ( programs whose code is commented with constraints, typically logical expressions capturing pre/post conditions and invariants ). Different perspectives can be considered: ……..

10. CROSSmeeting UM, Fev. 2010 10 Objectives – substask2 a) Given a traditional slicing criterion, perform backward slicing in order to identify all the pre/post conditions involving that variable; b) Given a pre/post condition of a method, perform forward slicing in order to identify all the program statements that depends on that condition;

11. CROSSmeeting UM, Fev. 2010 11 Objectives – substask2 c) Given an annotated procedure, identify all its statements that do not contribute to the verification of the post- condition; d) Given an annotated procedure and set of procedure-calls remove from the procedure all the statements that do not contribute to calling needs;

12. CROSSmeeting UM, Fev. 2010 12 Objectives – substask2 e) Given an annotated procedure, extract and display the annotation in order to aid in its reuse; f) Given an annotated procedure verify the precondition satisfiability at each calling point; g) Given a procedure, infer its annotation

13. CROSSmeeting UM, Fev. 2010 13 Objectives – substask3 Development of new instrument for visualization and manipulation of annotated procedures : Labeled Control Flow Graph Labeled System Dependency Graph

14. CROSSmeeting UM, Fev. 2010 14 Objectives – substask4 Application of slicing techniques to reverse engineering of specific software facets --business logic, user interfaces, architectural issue, etc.-- to assess a given SwSystem. ( verify its compliance with the problem requirements )

15. CROSSmeeting UM, Fev. 2010 15 Objectives – substask4 To attain this objective, it is required to change the traditional definition of slicing criterion in order to deal with the vocabulary of each specific facet.

16. CROSSmeeting UM, Fev. 2010 16 Objectives – substask5 Dynamic slicing techniques to extract specific behavior, dealing with strong dynamic characteristics.

17. CROSSmeeting UM, Fev. 2010 17Conclusion Present Status: Tasks 1, 2, 3 under-development (Ph.D. work + BI / M.Sc.) Future: 2nd BI