Parallel Sessions: Compilers Moderator: Quinlan Panelists: Milind Kulkarni (Purdue), David Padua (UIUC), P. Sadayappan (Ohio State), Armando Solar-Lezama (MIT), Olivier Tardieu (IBM), Nicolas Vasilache (Reservoir)

Panel Introductions Miland: memory hierarchy / locality : highly demanded, even with Polyhedral David: how to evaluate quality : compilers react differently to different codes understand more about optimization problems : how to apply them. predict the ultimate performance gain Saday: landscape : architecture, data movement, up-bound analysis, irregular apps, analyze apps publication metrics: new ideas/prototypes vs. compiler work with real impact on apps. Saman: need long term evaluation. Incentives to attract researchers. JMC:finish compilers to deal with millions lines of codes. Armando Compiler fire and forget thing, all or nothing: too conservative → force manual code transformation. solution: give control, give feedback, support to users. Interactive compiler/refinement process

Panel Introductions Saman: reverse/rollback the process to check, need good UI people. funding for UI/visualization Olivier X10 language: ready to support CUDA using the place concept, future work for NUMA Nicolas confirm previous issues: issues, interaction with users. new architecture challenges: parameterized code generation Algorithms: correct representation for loop, communication, data structure synthesis, how to put them together, apply combined transformation.

Panel Questions Panel questions * one rewrite/language: – high level specification like using Matlab – multiple, iterative, localized rewrites. – high level description for app features: locality, etc. – DSL, new general constructs like array loops, goto * new/old compiler techniques: – array region/array section analysis → mulitithreaded, heterogeneous envionment. – Analysis : high level gap SSA – Interactive/feedback