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Re: Value Range Propagation Patch (Version 4)



  In message <397C8BAA.C17B3DEB@moene.indiv.nluug.nl>you write:
  > There is a interesting irony about value range propagation:  It tends to
  > spend most of its time on routines/code that ultimately will take the
  > least time to execute anyway ;-)
  > [ Mainly because, as the human programmer knows - they won't take long
  >   to execute, so why should _he_ spend any time to optimize them ? ]
  > 
  > I just saw it spend 5:26 minutes on a routine that will take care of the
  > initialisation of some arrays in a split second when executing :-)
  > [ That 5+ minutes is without array bounds checking ]
  > 
  > How do you get it to focus its efforts on code that really matters ?
Profiling :-)  Seriously though we could look at running VRP over subgraphs
and just do it for nested loops.

jeff


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