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A Comprehensive Analysis of Indirect Branch Prediction

  • Oliverio J. Santana
  • Ayose Falcón
  • Enrique Fernández
  • Pedro Medina
  • Alex Ramírez
  • Mateo Valero
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2327)

Abstract

Indirect branch prediction is a performance limiting factor for current computer systems, preventing superscalar processors from exploiting the available ILP. Indirect branches are responsible for 55.7% of mispredictions in our benchmark set, although they only stand for 15.5% of dynamic branches. Moreover, a 10.8% average IPC speedup is achievable by perfectly predicting all indirect branches.

The Multi-Stage Cascaded Predictor (MSCP) is a mechanism proposed for improving indirect branch prediction. In this paper, we show that a MSCP can replace a BTB and accurately predict the target address of both indirect and non-indirect branches. We do a detailed analysis of MSCP behavior and evaluate it in a realistic setup, showing that a 5.7% average IPC speedup is achievable.

Keywords

microarchitecture branch prediction Branch Target Buffer indirect branch Multi-Stage Cascaded Predictor 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Oliverio J. Santana
    • 1
  • Ayose Falcón
    • 1
  • Enrique Fernández
    • 2
  • Pedro Medina
    • 2
  • Alex Ramírez
    • 1
  • Mateo Valero
    • 1
  1. 1.Dpto. de Arquitectura de ComputadoresUniversidad Politécnica de CataluccñaSpain
  2. 2.Dpto. de Informática y SistemasUniversidad de Las Palmas de Gran CanariaSpain

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