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M. Kirner:
"Automatic Loop Bound Analysis of Programs written in C";
Supervisor: P. Puschner, R. Kirner; Institut für Technische Informatik, 2006; final examination: 2006.

The knowledge about the worst-case execution time is important for the design of real-time systems. Without a save upper bound for the execution time it cannot be guaranteed that the system will meet all its deadlines. As part of the worst-case execution-time calculation, it is important to know how many times the body of a loop will be executed after entering the loop header for the first time. Traditionally, loop bounds had to be provided explicitly, in the form of source-code annotations to support timing analysis of real-time programs. This thesis presents a method that is able to calculate a lower and an upper bound for the number of iterations of different loop types by analyzing the semantics of a source code, written in the high-level language C. Only if the number of iterations of a loop depends on unknown variable values, annotations about the value bounds have to be given in the source code. The analysis of loops is done at the source code level. For every supported loop, the result of the loop-bound calculation is written back into the source file to support the further steps of the WCET analysis.