1. Presented by: Sameer Kulkarni
Improving Both the Performance Benefits and Speed of Optimization Phase Sequence Searches- Kulkarni, Jantz and Whalley
Presented by: Sameer Kulkarni
Dept of Computer & Information Sciences
University of Delaware

2. Terms used Phase Ordering Genetic Algorithms Performance measurements
Benchmarks
Search granularity

3. Introduction Function vs. program level Granularity Embedded Systems
Emulation
Cost benefits
Hybrid Search

4. Ideal Solution? Oracle  Perfect sequence at the very start
Wise Man Solution  Given the present code predict the best optimization solution

5. Wise Man
Understand Compilers
Optimizations
Source Code ?

6. Possible Solutions Pruning the search space Genetic Algorithms
Estimating running times
Precompiled choices
Have multiple images of the library and chose the best one depending on the architecture.

7. Genetic Algorithms
Fast Searches for Effective Optimization Phase Sequences, Kulkarni et al. PLDI ‘04

8. Exhaustive vs Heuristic [2]

9. Related Work Genetic Algorithms Other Evolutionary Techniques
HMMs (CGO 06)
Other Statistical methods
Optimization Space Exploration

10. Present work Granularity Function Level File Level Program Level
Hybrid

11. Experimental Setup VPO (Very Portable Optimizer)
Base Genetic Algorithm
Redundancy elimination

12. VPO
Single IR
Simplified phase ordering
Configurable/modifiable

13. Redundancy Elimination
Identical Sequence
Identical Active Sequence
Identical Function instance
Equivalent Function Instance

14. Improvement…?
120 days > 12.5 days

15. Granularities Studied…
Function Level
File Level
Program Level
Hybrid
…all compared to batch compilation

16. Graphs, graphs and more graphs… 

17. Search Requirements

18. Are they any good?

19. Performance ??

20. Future Work Other machine learning algorithms Reduce granularity
Use a cluster to reduce search / learning time

21. Conclusion
Reduced search overhead

22. Questions What is JikesRVM and what it is not bytecode to machine code
Compilation : from website link, untar, run the java config command only once, create .ant.properties file. Run ant
Checking that it is working: rvm check path
How do you optimize, command line parameters.
Different IRs and optimization on the IRs.
For more information please go thru
Some Code snippets
Adding new CommandLine Parameters space sensitive