Functional Validation of System - level Loop Transformations
نویسندگان
چکیده
This paper presents new results for formal validation of system-level loop transformations in the context of power eecient caching. Our main target domain consists of data-dominated applications in the multi-media area, dealing with complex loop nests containing composite data types like (multi-dimensional) arrays and lists. Global transformations applied on such loop nests cannot be formally veriied fully automatically with existing veriication approaches, except by unrolling the loops, which is infeasible in a multi-media context with heavily nested loops and large loop bounds. In this paper, our basic veriication technique dealing with this problem, based on polyhedral modeling is extended to make it eeective also for more complex realistic examples. Experiments on examples which have been translated for power eecient mapping on a processor with a memory and cache hierarchy show that the method is suited for arbitrary (irregularly nested) loop nests with complex conditional clauses. We will also demonstrate the power which can be gained by our transformation methodology for a particular cache memory organisation of the vocoder.
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