Interactive debugging system
- 1. SRI RAMANUJAR ENGINEERING COLLEGE DEPARTMENT OF COMPUTER SCIENCE & ENGINEERING SYSTEM SOFTWARE INTERACTIVE DEBUGGING SYSTEM By Florence priyadarshini .W (CSE)
- 3. What is Interactive debugging system? The Interactive debugging system facilitates the programmers in testing and debugging of programs.
- 4. Approaches to debugging Print statements Printing to log files Heap checking Reverse execution
- 5. Debugging functions and capabilities Unit test Functions Tracing and Traceback Program display Capabilities Incremental Aspects Debugging functions and capabilities
- 6. Functions Execution sequencing Break points Conditional expression Gaits Definition It is observation and control flow of program execution. A break point cause the execution to be suspended . Specified conditional expressions cause execution to be suspended. Run the program in various speeds. Conditions Can be halted after a fixed number of instructions are executed. Specific point program When any of the condition become true as defined by user. Runs in good graphical representation of a program Program resumption no yes no no Unit test functions
- 7. Tracing and Traceback Functions Tracing Traceback definitions Used to trace the flow of execution logic and data modifications Shows the path by which the current execution of the statement is reached. Conditions Only after modifications Path of current statement
- 8. Program display capabilities It displays the program being debugged with statement numbers. The user can control the level at which display occurs.
- 9. INCREMENTAL ASPECTS What are the aspects ? 1. Modification during debugging. 2. Recompile incrementally during debugging. What it should do ? 1. Save all the debugging specifications such as break points etc. 2. It must symbolically display or modify the content of variables and constants of a program and then continue execution. How it helps ? Programmer need not reissue all debugging commands.
- 10. Needs for Debugging System 1. Able to determine the language of program in which it is written so it must be language independent 2. It should get its context accordingly When does a context used ? Debugger switches using context when one program written in one language calls a program written in the other language. Each context has its own effect 1.Assignment statements : COBOL : MOV 3.5 TO A FORTRAN : A = 3.5 2.Conditional expression: COBOL : IF A NOT EQUAL TO B FORTRAN : IF (A.NE.B) 3.The notation used is based on the language being debugged.
- 11. Example : Press F12 for Development window Language used : HTML with PHP code
- 12. After clicking Maps button Language used: HTML with JAVA script
- 13. Language translator : 1. Debugger should have access to information collected by language translator. 2. Translators produce the required information in a standard external form regardless of internal form used in translator. 3. Interface modules that can respond to request for information in a standard way regardless of language. Debugger Access Translator C Format JAVA Format COBOL Format TRANSLATOR OUTPUT COBOL Format JAVA Format C Format Translator output Input Debugger Translator output
- 14. Optimized code What is optimized code? The process of modifying the software system to make it to work more efficiently. Uses: 1. Lower memory storage 2. Less power How is it done ? 1. Invariant expressions can be removed form loop. 2. Separate loop can be combined into a single loop. 3. Redundant expressions can be eliminated. 4. Elimination of unnecessary branch instructions. Disadvantages: Due to code arrangement 1. Affect tracing 2. Affect Breakpoints 3. Affect Statement counts
- 15. Relationship with other Parts of the System 1.Runtime environment: Interactive debugger must be a part of runtime environment. When an error is found immediate debugging must be possible. Reason: Impossible to reproduce the failure in other environments. 2. Production environment: User should be able to debug in a production environment. Cause: If a application fails during a program run , work dependent on that application stops. 3. Security and integrity: Specific authorization should be given. Limits: 1. An unauthorized user cannot access any data. 2.Should not be possible to use debuggers to interfere with any aspect of system integrity 4.Language compilers and interpreters: Must co-ordinate its activities with existing and future language compilers and interpreters. Existing : Maintained Future : Install new upgrades
- 16. What are the Criteria for User-interface ? 1. User friendly. 2. Use Full screen display and windowing display 3. Use menu bars a.) Menus should have the heading of the task b.) Possible to go directly to menus and it should not entire hierarchy. 4. Command Language: a.)It must be clear, logical, simple syntax b.)Should minimize punctuations eg : { } , / , etc …. 5. Available Help Facility .