Automatic Storage Optimization of Arrays in Affine Loop Nests

154 Pages·2017·0.73 MB·English

Automatic Storage Optimization of Arrays in Affine
Loop Nests
A THESIS
SUBMITTED FOR THE DEGREE OF
Doctor of Philosophy
IN COMPUTER SCIENCE AND ENGINEERING
by
Somashekaracharya G. Bhaskaracharya
Computer Science and Automation
Indian Institute of Science
BANGALORE – 560 012
July 2016

© Somashekaracharya G. Bhaskaracharya
July 2016
All rights reserved

TO
My family, friends and colleagues

ACKNOWLEDGEMENTS
I am deeply indebted to my advisor, Dr. Uday Bondhugula, for guiding me at every stage
of my research work. It has truly been an honour to work with him. I hope I have justified
the trust he invested in me when he agreed to be my advisor, despite the commitment
to academic work only being of a part-time nature from my side. His constant support
and optimism were major factors in helping me juggle both, academic research and office
work at National Instruments, through the various ups and downs in these last five years.
He was ever ready to discuss new ideas, however wild (I still remember a discussion on
the storage optimization problem we had in the Dubai airport terminal, very late into the
night, while waiting for our return flight to Bangalore). And almost invariably, I returned
from such discussions with more ideas to work on. This work would, quite simply, not
have been possible without his tremendous guidance. I offer my sincerest thanks!
IwouldliketoexpressmygratitudetoDr. AlbertCohenforallhisinsightfulcomments
and suggestions. Interactions with him, over email as well as in person every now and
then, helped me immensely in refining the ideas presented here. His belief in their merit
kept me inspired and motivated. I would also like to thank my organizational supervisor,
Dr. Dinesh Nair, who gave me complete freedom in my research work.
I have greatly benefited through help from various other quarters. Firstly, I would like
to thank my labmates Chandan, Roshan, Irshad, Vinay, Raviteja, Aravind, Thejas, Vinayak
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for their generous assistance and suggestions on so many occasions, despite already being
burdened with their own work. I am also very grateful to my friends and colleagues at
NI who went out of their way in helping me pursue my academic goals to the fullest
extent possible – to Anand, Gowrishankar, Rajanikanth for creating this opportunity for
me; to Praveen, Subbaiah and Prashanth for their managerial support; and last but not
theleast, tomy team-matesNikhil, Bharath, Rakesh, ChethanandAshwin. I wouldliketo
acknowledge the monetary assistance provided by NI towards my studies.
As the proverbial dwarf standing on the shoulders of giants, I owe a great deal to
the authors of various tools (such as Clan, GLPK, ISL, Pet, Pluto etc) that I have used to
implement the ideas presented in this work. Valuable feedback from several anonymous
reviewers was also very helpful – my thanks to all these reviewers.
Finally, I would like to dedicate this work to my parents, G. S. Bhaskaracharya and
H. K. Pushpa Latha, who have always encouraged me in all my pursuits; my thanks also
to my brother and sister-in-law. The unflinching moral support at home helped me stay
focused on my work.
PUBLICATIONS BASED ON THIS THESIS
1. Somashekaracharya G. Bhaskaracharya, Uday Bondhugula, PolyGLoT: A Polyhedral
Loop Transformation Framework for a Graphical Dataflow Language, International
conference on Compiler Construction (CC 2013), Rome, Italy, pages 123 - 143,
March 2013.
2. SomashekaracharyaG.Bhaskaracharya,UdayBondhugula,AlbertCohen,Automatic
Storage Optimization for Arrays, ACM Transactions on Programming Languages and
Systems (TOPLAS), vol 38, issue 3, pages 11:1–11:23, April 2016.
3. Somashekaracharya G. Bhaskaracharya, Uday Bondhugula, Albert Cohen, SMO: An
IntegratedApproachtoIntra-ArrayandInter-ArrayStorageOptimization,ACMSIGPLAN-
SIGACTSymposiumonPrinciplesofProgrammingLanguages(POPL),St.Petersberg,
USA, pages 526 - 538, Jan 2016.
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