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Re: The bloat sweepstakes...


  In message <20011022003928.E3425@codesourcery.com>you write:
  > On Wed, Oct 17, 2001 at 07:08:32PM -0600, law@redhat.com wrote:
  > >   In message <20011010150953.U9432@codesourcery.com>you write:
  > >   > I think costs never get higher than 10 or so;
  > > They certainly do get higher than 10.  Also remember that costs accumulat
  > e
  > > across the uses of a register.  Making them an unsigned character probabl
  > y
  > > is not a wise idea.
  > 
  > The arrays that are taking up lots of space are the ones in regclass.c
  > (move_cost, may_move_in_cost, may_move_out_cost), and it looks to me
  > like they don't ever get very high.  In fact, 65536 is being used in
  > regclass as infinity, suggesting that it would at least be safe to
  > make them short.
A short may work.  Then again it may not -- we've certainly seen costs overflow
a short in the past on some ports.  When that's happened in the past we have
simply twiddled the costs for the port in question to make overflow less
likely -- certainly with a suitably ugly function we could still overflow.


jeff


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