By Topic

Constraint satisfaction in incremental placement with application to performance optimization under power constraints

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Huan Ren ; Dept. of ECE, University of Illinois-Chicago, USA ; Shantanu Dutt

We present new techniques for explicit constraint satisfaction in the incremental placement process. Our algorithm employs a Lagrangian relaxation (LR) type approach in the analytical global placement stage to solve the constrained optimization problem. We establish theoretical results that prove the optimality of this stage. In the detailed placement stage, we develop a constraint-monitoring and satisfaction mechanism in a network (n/w) flow based detailed placement framework proposed recently, and empirically show its near-optimality. We establish the effectiveness of our general constraint-satisfaction methods by applying them to the problem of timing-driven optimization under power constraints. We overlay our algorithms on a recently developed unconstrained timing-driven incremental placement method flow-place. On a large number of benchmarks with up to 210K cells, our constraint satisfaction algorithms obtain an average timing improvement of 12.4% under a 3% power increase limit (the actual average power increase incurred is only 2.1%), while the original unconstrained method gives an average power increase of 8.4% for a timing improvement of 17.3%. Our techniques thus yield a tradeoff of 75% power improvement to 28% timing deterioration for the given constraint. Our constraint-satisfying incremental placer is also quite fast, e.g., its run time for the 210 K-cell circuit ibm18 is only 1541 secs.

Published in:

Computer Design, 2007. ICCD 2007. 25th International Conference on

Date of Conference:

7-10 Oct. 2007