Title :
Data flow partitioning with clock period and latency constraints
Author :
Liu, Lung-Tien ; Shih, Minshine ; Lillis, John ; Cheng, Chung-Kuan
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
fDate :
3/1/1997 12:00:00 AM
Abstract :
We propose an efficient performance-driven two-way partitioning algorithm to take into account clock period and latency with retiming. We model the problem with a quadratic programming formulation to minimize the crossing edge count with nonlinear timing constraints. By using a Lagrangian Approach on Modular Partitioning (LAMP), we merge nonlinear constraints into the objective function. We then decompose the problem into primal and dual subprograms. The primal program is solved by a heuristic quadratic Boolean programming approach and the dual program is solved by a subgradient method using a cycle mean method. Experimental results on seven industrial circuits have demonstrated our algorithm is able to achieve an average of 23.25% clock period and latency reductions compared to the best results produced by 20 rum on each test case using a Fiduccia-Mattheyses algorithm. In terms of the average number of crossing edges, our results are only 1.85% more than those of the Fiduccia-Mattheyses algorithm without timing constraints. Compared with previous network flow based approach, our algorithm reduces the average crossing edge count by 14.59%. Furthermore, an average of 7.70% clock period and latency reductions are achieved,
Keywords :
circuit analysis computing; data flow graphs; digital circuits; iterative methods; logic partitioning; quadratic programming; timing; LAMP; Lagrangian Approach on Modular Partitioning; clock period constraints; crossing edge count reduction; cycle mean method; data flow partitioning; digital circuits; dual subprogram; heuristic quadratic Boolean programming; latency constraints; nonlinear constraints; objective function; performance-driven two-way partitioning algorithm; primal subprogram; quadratic programming formulation; retiming; subgradient method; Circuit optimization; Circuit testing; Clocks; Lagrangian functions; Lamps; Linear programming; Partitioning algorithms; Propagation delay; Quadratic programming; Timing;
Journal_Title :
Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on