Abstract:
In this paper, a tool for automatically generating test programs for MIPS64 memory management units is described. The solution is based on the MicroTESK framework being developed at the Institute for System Programming of the Russian Academy of Sciences. The tool consists of two parts: an architecture-independent test program generation core and MIPS64 memory subsystem specifications. Such separation is not a new principle in the area: it is applied in a number of industrial test program generators, including IBM's Genesys-Pro. The main distinction is in how specifications are represented, what sort of information is extracted from them, and how that information is exploited. In the suggested approach, specifications comprise descriptions of the memory access instructions, loads and stores, and definition of the memory management mechanisms such as translation lookaside buffers, page tables, table lookup units, and caches. A dedicated problem-oriented language, called mmuSL, is used for the task. The tool analyzes the mmuSL specifications and extracts all possible instruction execution paths as well as all possible inter-path dependencies. The extracted information is used to systematically enumerate test programs for a given user-defined test template and allows exhaustively exercising co-execution of the template instructions, including corner cases. Test data for a particular program are generated by using symbolic execution and constraint solving techniques.
Keywords:microprocessor, memory management unit, caching, address translation, formal specification, test program, test program generation, MIPS64.