Automatically assigned DDC number: 00435

Manually assigned DDC number: 00435

Number of references: 8

Title: A Dynamic Approach to Improve the Accuracy of Data Speculation

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Subject: Guri S. Sohi,Andreas I. Moshovos,Scott E. Breach,T. N. Vijaykumar,Gurindar S. Sohi A Dynamic Approach to Improve the Accuracy of Data Speculation

Description: Data speculation is used in instruction-level parallel (ILP) processors to allow early execution of an instruction before a logically preceding instruction on which it may be data dependent. If the instruction is independent, data speculation succeeds; if not, it fails, and the two instructions must be synchronized. This paper considers dynamic techniques to improve the accuracy with which data speculation is carried out. We propose dynamic techniques: (i) to predict if the execution of an instruction is likely to result in a data misspeculation, and (ii) to provide the synchronization needed to avoid a misspeculation. Experimental results evaluating the effectiveness of the proposed techniques are presented within the context of a Multiscalar processor. 1 Introduction Speculative execution is an integral part of modern ILP processors, be they statically- or dynamically-scheduled designs. Speculation takes on two forms: control speculation and data speculation. Control speculation imp...

Contributor: The Pennsylvania State University CiteSeer Archives

Publisher: unknown

Date: 1996-06-24

Pubyear: 1996

Format: ps

Identifier: http://citeseer.ist.psu.edu/169698.html

Source: ftp://ftp.cs.wisc.edu/tech-reports/reports/96/tr1316.ps.Z

Language: en

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Rights: unrestricted

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