Non-transparent debugging for software-pipelined loops

Abstract

This paper tackles the problem of providing correct information about program variable values in a software-pipelined loop through a non-transparent debugging approach. Since modern processors provide instruction level parallelism, software pipelining techniques have been developed to achieve better performances, especially in the context of embedded systems. Indeed, the effectiveness of software pipelining on such systems has been demonstrated both theoretically and experimentally. As it overlaps iterations and reorders statements, it also makes standard debugging information irrelevant. Hence debugging a loop which has been software-pipelined becomes very difficult. In this paper, we propose a solution relying on selected information to be generated by the compiler and an algorithm for the debugger not to mislead the user.