Simple type-based alias analysis for a VLIW processor

Abstract

Major C/C++ compilers use their own implements of type-based alias analysis; however, the impact of such algorithms on VLIW (Very Long Instruction Word) processors is not explored. This paper describes an implementation and effects of a simple type-based alias analysis known as strict-aliasing in the C/C++ compiler for Elbrus processor. Elbrus is a general-purpose VLIW microprocessor that relies on compiler optimizations for good performance. This paper demonstrates that strict-aliasing is a fast and scalable alias analysing technique. SPEC CPU2006 benchmarks measurement showed in the mean execution speed improvement of 28.6% for INT tests and 13.3% for FP tests in per module compilation mode. The measurement of whole-program mode showed 4.3% execution speed improvement for FP tests and 1.9% speed improvement for INT tests. These results illustrate that strict-aliasing can serve as a substitute for tradidional analysis in per module build mode and also disambiguate additional pointers in whole-program build mode.