@techreport{TR-IC-03-18, number = {IC-03-18}, author = {Nahri Moreano and Guido Araujo and Cid C. de Souza}, title = {{CDFG} Merging for Reconfigurable Architectures}, month = {October}, year = {2003}, institution = {Institute of Computing, University of Campinas}, note = {In English, 9 pages. \par\selectlanguage{english}\textbf{Abstract} Reconfigurable systems have been proved to achieve significant performance speedup through architectures that map the most time-consuming application kernel modules or inner-loops to a reconfigurable datapath. As each portion of the application starts to execute, the system reconfigures the datapath so as to perform the corresponding computation. The reconfigurable datapath should have as few and simple hardware blocks and interconnections as possible, in order to reduce its cost, area, power consumption, and reconfiguration overhead. Thus hardware blocks and interconnections should be reused across the application as much as possible. We represent each piece of the application as a control/data-flow graph (CDFG) and merge them together, synthesizing a single reconfigurable datapath. The CDFG merging process enables the reuse of hardware blocks and interconnections by identifying similarities among the CDFGs, and producing a resulting datapath that can be dynamically reconfigured to work for each CDFG and has a minimum area cost, when considering both hardware blocks and interconnections. In this report we formalize the CDFG merge problem and we present a proof that it is NP-complete, by reducing the subgraph isomorphism problem to it. } }