Spi Alignment and Distribution Is Not (always) Np-hard Alignment and Distribution Is Not (always) Np-hard Alignment and Distribution Is Not (always) Np-hard

نویسندگان

  • Vincent BOUDET
  • Fabrice RASTELLO
  • Yves ROBERT
  • Vincent Boudet
  • Fabrice Rastello
  • Yves Robert
چکیده

In this paper, an eecient algorithm to simultaneously implement array alignment and data/computation distribution is introduced and evaluated. We re-visit previous work of Li and Chen 13, 14], and we show that their alignment step should not be conducted without preserving the potential parallelism. In other words, the optimal alignment may well sequentialize computations, whatever the distribution after-wards. We provide an eecient algorithm that handles alignment and data/computation distribution simultaneously. The good news is that several important instances of the whole alignment/distribution problem have polynomial complexity, while alignment itself is NP-complete 13]. Mots-cl es: techniques de compilation, boucles parall eles, alignement, distribution, r egle du \the owner computes". Abstract In this paper, an eecient algorithm to simultaneously implement array alignment and data/computation distribution is introduced and evaluated. We re-visit previous work of Li and Chen 13, 14], and we show that their alignment step should not be conducted without preserving the potential parallelism. In other words, the optimal alignment may well sequen-tialize computations, whatever the distribution afterwards. We provide an eecient algorithm that handles alignment and data/computation distribution simultaneously. The good news is that several important instances of the whole alignment/distribution problem have polynomial complexity, while alignment itself is NP-complete 13].

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تاریخ انتشار 1998