WCET Analysis of Superscalar Processors Using Simulation With Coloured Petri Nets

Determining a tight WCET of a block of code to be executed on a modern superscalar processor architecture is becoming ever more difficult due to the dynamic behaviour exhibited by current processors, which include dynamic scheduling features such as speculative and out-of-order execution in the context of multiple execution units with deep pipelines. We describe the use of Coloured Petri Nets (CP-nets) in a simulation based approach to this problem. A complex model of a generic processor architecture is described, with emphasis on the modelling strategy for obtaining the WCET and an analysis of the results.