Authors: Yun-Kwan Kim, Won Shin, Tae-Wan Kim and Chun-Hyon Chang
Static execution time analysis is one of the most important approaches in real time system to guarantee timing reliability. Analyzing execution time in static manner is tedious, due to unbounded external inputs in loops and control flow. In the past decades there has been substantial research undergone for single-path programming and user annotation. However, it was hard to take an input dependency away completely, and to analysis varied execution paths caused by fixed user annotations. In this paper we present a methodology to analyze an external input for an execution time analysis that offers more useful information for user and predicts interval of the input. Our proposed method considers constraint conditions from branches caused by the input to restrict to available interval for execution time analysis. It provides information of execution time to user by the restricted interval. And it allows input after analysis that was not possible before. Thus our approach increases effectiveness to analyze inputs and improves usability of static execution time analysis tools.
Keywords: Execution Time Analysis, WCET, Real-time System,Input dependency