ScholarlyCommons

Title

Encoding Mini-Graphs With Handle Prefix Outlining

Author(s)

Anne W. Bracy, University of Pennsylvania
Amir Roth, University of PennsylvaniaFollow

Document Type

Technical Report

Date of this Version

January 2008

Comments

University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-08-36

Abstract

Recently proposed techniques like mini-graphs, CCA-subgraphs, and static strands exploit application-specific compound or fused instructions to reduce execution time, energy consumption, and/or processor complexity. To achieve their full potential, these techniques rely on static tools to identify common instruction sequences that make good fusion candidates. As a result, they also rely on ISA extension facilities that can encode these chosen instruction groups in a way that supports efficient execution on fusion-enabled hardware as well as compatibility across different implementations, including fusion-agnostic implementations.

This paper describes handle prefix outlining, the ISA extension scheme used by mini-graph processors. Handle prefix outlining can be thought of as a hybrid of the encoding scheme used by three previous instruction aggregation techniques: PRISC, static strands, and CCA-subgraphs. It combines the best features of each scheme to deliver both full compatibility and execution efficiency on fusion-enabled processors.

Keywords

Instruction fusion, ISA extension, outlining

Recommended Citation

Anne W. Bracy and Amir Roth, "Encoding Mini-Graphs With Handle Prefix Outlining", . January 2008.