Improving the WCET computation time by IPET using control flow graph partitioning
نویسندگان
چکیده
Implicit Path Enumeration Technique (IPET) is currently largely used to compute Worst Case Execution Time (WCET) by modeling control flow and architecture using integer linear programming (ILP). As precise architecture effects requires a lot of constraints, the super-linear complexity of the ILP solver makes computation times bigger and bigger. In this paper, we propose to split the control flow of the program into smaller parts where a local WCET can be computed faster as the resulting ILP system is smaller and to combine these local results to get the overall WCET without loss of precision. The experimentation in our tool OTAWA with lp_solve solver has shown an average computation improvement of 6.5 times.
منابع مشابه
Comparison of Implicit Path Enumeration and Model Checking Based WCET Analysis
In this paper, we present our new worst-case execution time (WCET) analysis tool for Java processors, supporting both implicit path enumeration (IPET) and model checking based execution time estimation. Even though model checking is significantly more expensive than IPET, it simplifies accurate modeling of pipelines and caches. Experimental results using the UPPAAL model checker indicate that m...
متن کاملComparison of ILP and Model Checking based WCET Analysis
In this report, we present our new worst-case execution time (WCET) analysis tool for Java processors, supporting both implicit path enumeration (IPET) and model checking based execution time estimation. Even though model checking is significantly more expensive than IPET, it offers new possibilities, such as modeling pipeline effects. Experimental results using UPPAAL indicate that model check...
متن کاملContext-sensitive Parametric WCET Analysis
In this paper, we propose a WCET analysis that focuses on two aspects. First, it supports contextsensitive hardware and software timing effects, meaning that it is sensitive to the execution history of the program and thus can account for effects like cache persistence, triangular loop, etc. Second, it supports the introduction of parameters in both the software model (e.g. parametric loop boun...
متن کاملFully Automatic, Parametric Worst-Case Execution Time Analysis
Worst-Case Execution Time (WCET) analysis means to compute a safe upper bound to the execution time of a piece of code. Parametric WCET analysis yields symbolic upper bounds: expressions that may contain parameters. These parameters may represent, for instance, values of input parameters to the program, or maximal iteration counts for loops. We describe a technique for fully automatic parametri...
متن کاملOn the sensitivity of WCET estimates to the variability of basic blocks execution times
The Implicit Path Enumeration Technique (IPET) is a very popular approach to evaluate the Worst-Case Execution Time (WCET) of hard real-time applications. It computes the execution time of an execution path as the sum of the execution times of the basic blocks weighted by their respective execution counts. Several techniques to estimate the execution time of a block taking into account every po...
متن کامل