Conditional resource sharing

Ki Soo Hwang, Albert E. Casavant Martin Dragomirecky, and Manuel A. d Abreu, "Constrained Conditional Resource Sharing in Pipeline Synthesis , Proc. oflCCAD 88, pages 52-55, November 1988. 

K. Hwang, A. Casavant, M. Dragomirecky, and M. d Abreu, Constrained Conditional Resource Sharing in Pipeline Synthesis, in ICCAD-88, pp. 52-55, 1988. 

K. S. Hwang et al., "Constrained Conditional Resource Sharing in Pipeline Synthesis", Proc, of the International Corf, on CAD, Nov. 1988, pp. 52-55. M.C. McFarland, "Reevaluating the Design Space for Register-Transfer Hardware Synthesis", Proc. of ICC AD, Nov. 1987, pp.262-265. 

K. Wakabayshi and T. Yoshimura. A resource sharing and control synthesis method for conditional branches. In Proc. of the ICCAD, Santa Clara, pages 62-65, 1989. 

K. Wakabayashi and T. Yoshimura, A Resource Sharing Control Synthesis Method for Conditional Branches, ICCAD 89, pp. 62-65, Santa Clara, CA, November 1989. 

Some systems consider mutual exclusiveness of some operations in conditional branches[12, 17, 11]. However, most of them search the sharing pairs among operations in each c-step after usual scheduling. Therefore, they cannot produce optimal control for each path, and cannot attain resource sharing globally. 

Compared with the above systems, the most important feature of the Cyber system is to achieve to exploit both potential concurrency and alternation at the same time in a simple and systematical way, by considering data dependencies and control structure in behavioral description. Therefore, it can synthesize more efficient control and more completely resource sharing from description containing nested conditional branchings and loops while maintaining the same ability to exploit potential concurrency with other system, and without incresise of computational complexity. Moreover, all possible paths for conditional branches are scheduled optimally. 

Resource sharing between operations in different c-step are heuristic and greedy now, but sharing between conditional mutual exclusive operaions are accomplish globally. 

The first ready list contains np nq naynb ric Nodes are sorted by the pf value the length from each node to the end node. A conditional operation always has larger priority function, because it is good for resource sharing as described in ACV section. When conditional node Up does not need FUs, ap is [0,0,0]. As node Up is resolved in c-step STl, aq is equal to e ([0,l,lj). Conditional node riq is unresolved in c-step STl, then aa becomes [1,1,1] ( =Ca or Cq ). Similarly, at, and ac becomes [0,1,1] and [0,1,1]. First, nodes np,nqfna,nj, is assigned to c-step STl. In c-step ST2, conditional node Uq is already resolved then ac becomes [0,1,0]. Consequently, it becomes possible that r%d (arf=[l,0,l]) and (ac=[0,l,0]) share one adder. 

Resource allocation refers to the process of sharing an arithmetic-logic-unit (ALU) under mutually-exclusive conditions. Consider the following if statement. 

In yet another case by Samii and Van Wassenhove ([85]), in Afghanistan, they describe a UNJLC website that provided security and weather updates, requests for logistics shipments (similar to a ride board in most campuses), road conditions, and more. The remaining coordination was left to individual agencies who used this information to seek out interested parties to share resources. This minimal coordination is termed coordination by default. 

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