Optimal Integrated VLIW Code Generation with Integer Linear Programming

  • Andrzej Bednarski
  • Christoph Kessler
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4128)


We give an Integer Linear Programming (ILP) solution that fully integrates all steps of code generation, i.e. instruction selection, register allocation and instruction scheduling, on the basic block level for VLIW processors.

In earlier work, we contributed a dynamic programming (DP) based method for optimal integrated code generation, implemented in our retargetable code generator OPTIMIST. In this paper we give first results to evaluate and compare our ILP formulation with our DP method on a VLIW processor. We also demonstrate how to precondition the ILP model by a heuristic relaxation of the DP method to improve ILP optimization time.


Dynamic Programming Integer Linear Programming Clock Cycle Basic Block Integer Linear Programming Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Andrzej Bednarski
    • 1
  • Christoph Kessler
    • 1
  1. 1.PELAB, Department of Computer and Information ScienceLinköpings universitetLinköpingSweden

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