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Vol: 47(61) No: 2 / June 2002        

Understanding Value Prediction through Complex Simulations
Adrian Florea
University"L. Blaga", Department of Computer Science, Str. E. Cioran, No. 4, Sibiu-2400, ROMANIA, phone: ++40-269-212716, e-mail: aflorea@vectra.ulbsibiu.ro
Lucian N. Vintan
University "L. Blaga", Department of Computer Science, Str. E. Cioran, No. 4, Sibiu-2400, ROMANIA, e-mail: vintan@jupiter.ulbsibiu.ro
Dorin Sima
University "L. Blaga", Department of Computer Science, Str. E. Cioran, No. 4, Sibiu-2400, ROMANIA


Keywords: advanced computer architectures, value locality, value prediction, pipeline, simulation, benchmarking.

Abstract
Through this paper we investigated the value locality degree present in real-worlds program, and extended the value locality concept to all general-purpose registers (MIPS architecture). Also we exploited this concept through a prediction mechanism of load instruction values from two distinct perspectives: producer-centric and memory-centric. To extract the maximum degree of load value locality we performed execution driven simulations on SPEC95 benchmarks with unbounded table sizes. The encouraging obtained results facilitate implementation of much simpler prediction structures (at most 32/64 locations), reducing the hardware cost and complexity.

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