Abstract
Loop unwinding is a known technique for reducing loop overhead, exposing parallelism and increasing the efficiency of pipelining. Traditional loop unwinding is limited to the innermost loop in a group of nested loops and the amount of unwinding is either fixed or has to be specified by the user, on a case by case basis. In this paper we present a general technique for automatically unwinding multiply nested loops, explain its advantages over other transformation techniques and illustrate its practical effectiveness. Loop Quantization could be beneficial by itself, or coupled with other loop transformations (e.g., Do-across).
This work is supported in part by NSF grant DCR 8502884, ONR grant N00014-86-K-0215, and the Cornell NSF Supercomputing Center.
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© 1988 Springer-Verlag Berlin Heidelberg
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Nicolau, A. (1988). Loop quantization or unwinding done right. In: Houstis, E.N., Papatheodorou, T.S., Polychronopoulos, C.D. (eds) Supercomputing. ICS 1987. Lecture Notes in Computer Science, vol 297. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-18991-2_17
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DOI: https://doi.org/10.1007/3-540-18991-2_17
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