Re: Selective Computation...

Joachim Durchholz <joachim_d@gmx.de>
31 Dec 2002 23:46:39 -0500

          From comp.compilers
Related articles
Selective Computation... saru@jeyan.eclipse.co.uk (Saru) (2002-12-26)
Re: Selective Computation... jeyan@jeyan.eclipse.co.uk (Saru) (2002-12-30)
Re: Selective Computation... saru@jeyan.eclipse.co.uk (Saru) (2002-12-30)
Re: Selective Computation... joachim_d@gmx.de (Joachim Durchholz) (2002-12-31)
Re: Selective Computation... thp@cs.ucr.edu (2003-01-17)
Re: Selective Computation... Patrick.Volteau@st.com (Patrick Volteau) (2003-01-20)
Re: Selective Computation... strohm@airmail.net (John R. Strohm) (2003-01-21)
Re: Selective Computation... andreas.gieriet@externsoft.ch (Andreas Gieriet) (2003-01-21)
Re: Selective Computation... liekweg@freenet.de (Florian Liekweg) (2003-01-21)
Re: Selective Computation... marcov@toad.stack.nl (Marco van de Voort) (2003-02-06)
| List of all articles for this month |
From: Joachim Durchholz <joachim_d@gmx.de>
Newsgroups: comp.compilers
Date: 31 Dec 2002 23:46:39 -0500
Organization: Compilers Central
References: 02-12-116
Keywords: optimize
Posted-Date: 31 Dec 2002 23:46:39 EST

Saru wrote:
> I have a computation which evaluates X as
>
> X=k1*(p+q)+k2*(p+q')+k3*(p'+q);
  >
  > [with k1, k2, k3 in {0,1}]


For me, this translates to


      X := 0
      if k1 = 1 then
          X := X + (p + q)
      end
      if k2 = 1 then
          X := X + (q + q')
      end
      if k3 = 1 then
          X := X + (p' + q)
      end


It doesn't look very "elegant", but doing things in the most
straightforward manner makes it easiest for the optimizer to figure out
what's going on and choose the appropriate optimizations (including
optimizations that we don't think of right now).


Or do I miss something here?


Regards,
Joachim

Post a followup to this message

Return to the comp.compilers page.
Search the comp.compilers archives again.