By David Keppel, Susan J. Eggers and Robert R. Henry.
Traditional compiler optimizations are either data-independent or optimize around common data values while retaining correct behavior for uncommon values. This paper examines "value-specific" data-dependent optimizations (VSO), where code is optimized at runtime around particular input values. Because VSO optimizes for the specific case, the resulting code is more efficient. However, since optimization is performed at runtime, the performance improvement must more than pay for the runtime compile costs. We describe two VSO implementation techniques and compare the performance of applications that have been implemented using both VSO and static code. The results demonstrate that VSO produces better code and often for reasonable input sizes. The machine-independent implementations showed speedups of up to 1.5 over static C code, and the machine-dependent versions showed speedups of up to 4.3 over static assembly code.
%A David Keppel
%A Susan J. Eggers
%A Robert R. Henry
%T Evaluating Runtime-Compiled Value-Specific Optimizations
%R UWCSE 93-11-02
%I University of Washington Department of Computer Science and
Engineering
%D November 1993
@techreport{KEH:93,
author={David Keppel and Susan J. Eggers and Robert R. Henry},
title={Evaluating Runtime-Compiled Value-Specific Optimizations},
number={UWCSE 93-11-02},
institution={University of Washington Department of Computer
Science and Engineering},
month={November},
year={1993}
}