Title :
Scheduling coarse-grain operations for VLIW processors
Author :
Busá, N.G. ; van der Werf, A. ; Bekooij, M.
Author_Institution :
Philips Res. Lab., Eindhoven, Netherlands
Abstract :
In order to speed up current DSP applications, complex hardware accelerators may be added in DSP architectures. This means that “coarse-grain” operations, characterized by a long latency and by a complex input-output timeshape, may be available to implement the given application. In a traditional scheduling approach, coarse-grain operations are treated as bulky atomic multi-cycle operations, under the worst case assumption that inputs and output are confined at the beginning and at the end of the operation itself. We propose a novel scheduling method for VLIW processors, where coarse-grain operations are decomposed into a number of fine input and output operations. Therefore, each I/O operation is scheduled separately in order to synchronize data communication among operations in a “just in time” fashion. This leads to a higher instruction level parallelism (ILP) in the processor, and decreases the number of registers needed in the architecture. The experiments show that embedding custom hardware accelerators in a VLIW datapath, as proposed in this paper, enhances performance keeping the VLIW controller´s microcode width small
Keywords :
data communication; digital signal processing chips; instruction sets; multiprocessing systems; parallel architectures; performance evaluation; scheduling; DSP applications; VLIW processors; atomic multi-cycle operations; coarse-grain operation scheduling; data communication; experiments; hardware accelerators; input output operation; instruction level parallelism; microcode; performance; registers; Delay; Digital signal processing; Grain size; Hardware; Laboratories; Processor scheduling; Registers; Synchronization; Telecommunication control; VLIW;
Conference_Titel :
System Synthesis, 2000. Proceedings. The 13th International Symposium on
Conference_Location :
Madrid
Print_ISBN :
0-7695-0765-4
DOI :
10.1109/ISSS.2000.874028