Title
Scalar Operand Networks
Abstract
The bypass paths and multiported register files in microprocessors serve as an implicit interconnect to communicate operand values among pipeline stages and multiple ALUs. Previous superscalar designs implemented this interconnect using centralized structures that do not scale with increasing ILP demands. In search of scalability, recent microprocessor designs in industry and academia exhibit a trend toward distributed resources such as partitioned register files, banked caches, multiple independent compute pipelines, and even multiple program counters. Some of these partitioned microprocessor designs have begun to implement bypassing and operand transport using point-to-point interconnects. We call interconnects optimized for scalar data transport, whether centralized or distributed, scalar operand networks. Although these networks share many of the challenges of multiprocessor networks such as scalability and deadlock avoidance, they have many unique requirements, including ultra-low latency (a few cycles versus tens of cycles) and ultra-fast operation-operand matching. This paper discusses the unique properties of scalar operand networks (SONs), examines alternative ways of implementing them, and introduces the AsTrO taxonomy to distinguish between them. It discusses the design of two alternative networks in the context of the Raw microprocessor, and presents timing, area, and energy statistics for a real implementation. The paper also presents a 5-tuple performance model for SONs and analyzes their performance sensitivity to network properties for ILP workloads.
Year
DOI
Venue
2005
10.1109/TPDS.2005.24
IEEE Trans. Parallel Distrib. Syst.
Keywords
Field
DocType
multiple alus,scalar operand network,operand transport,scalar data transport,raw microprocessor,recent microprocessor design,multiple program counter,scalar operand networks,5-tuple performance model,partitioned microprocessor design,operand value,computer architecture,statistics,instruction sets,parallel processing,low latency,logic design,program counter,point to point,register file
Logic synthesis,Computer science,Instruction set,Deadlock,Real-time computing,Distributed computing,Computer architecture,Pipeline transport,Operand,Parallel computing,Microprocessor,Multiprocessing,Scalability
Journal
Volume
Issue
ISSN
16
2
1045-9219
Citations 
PageRank 
References 
26
1.51
20
Authors
4
Name
Order
Citations
PageRank
Michael Bedford Taylor11707154.51
Walter Lee259343.59
Saman P. Amarasinghe34734395.55
Anant Agarwal44258483.35