Fri 30 Oct 2015 10:30 - 10:52 at Grand Station 1 - 9. Compilation & Dynamic Analysis Chair(s): Frank Tip

To optimize code effectively, compilers must deal with memory dependencies. However, the state-of-the-art heuristics available in the literature to track memory dependencies are inherently imprecise and computationally expensive. Consequently, the most advanced code transformations that compilers have today are ineffective when applied on real-world programs. The goal of this paper is to solve this conundrum through dynamic disambiguation of pointers. We provide different ways to determine at runtime when two memory locations can overlap. We then produce two versions of a code region: one that is aliasing-free - hence, easy to optimize - and another that is not. Our checks let us safely branch to the optimizable region. We have applied these ideas on Polly-LLVM, a loop optimizer built on top of the LLVM compilation infrastructure. Our experiments indicate that our method is precise, effective and useful: we can disambiguate every pair of pointer in the loop intensive Polybench benchmark suite. The result of this precision is code quality: the binaries we generate are 10% faster than those that Polly-LLVM produces without our optimization, at the -O3 optimization level of LLVM.

Fri 30 Oct

oopsla2015
10:30 - 12:00: OOPSLA - 9. Compilation & Dynamic Analysis at Grand Station 1
Chair(s): Frank TipSamsung Research America
oopsla201510:30 - 10:52
Talk
Pericles Rafael AlvesFederal University of Minas Gerais, Brazil, Fabian GruberINRIA, France, Johannes DoerfertSaarland University, Alexandros LabrineasINRIA, France, Tobias GrosserETH Zurich, Switzerland, Fabrice RastelloINRIA, France, Fernando Magno Quintão PereiraFederal University of Minas Gerais, Brazil
Link to publication
oopsla201510:52 - 11:15
Talk
Luca Della ToffolaETH Zurich, Switzerland, Michael PradelTU Darmstadt, Germany, Thomas GrossETH Zurich, Switzerland
DOI
oopsla201511:15 - 11:37
Talk
Wen-Chuan LeePurdue University, USA, Tao BaoPurdue University, USA, Yunhui ZhengPurdue University, USA, Xiangyu ZhangPurdue University, USA, Keval VoraUniversity of California at Riverside, USA, Rajiv GuptaUniversity of California at Riverside, USA
DOI
oopsla201511:37 - 12:00
Talk
Zhoulai FuUniversity of California at Davis, USA, Zhaojun BaiUniversity of California at Davis, USA, Zhendong SuUniversity of California at Davis, USA
DOI