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Re: Mainline space problem
On Mon, 2004-08-30 at 21:31, Daniel Berlin wrote:
> On Mon, 30 Aug 2004, James E Wilson wrote:
>
> > Bradley Lucier wrote:
> >> It would be nice if someone could try to fix the problem here. I don't
> >> know why it's still marked as UNCONFIRMED when Andrew has noted the
> >> precise allocation that fails.
> >
> > The problem Andrew pointed out isn't something that can be fixed. global
> > builds a conflict matrix that is quadratic in number of pseudos. So if you
> > have 100K+ pseudos, then you need 2GB+ of memory. This can't be fixed, at
> > least not in global.
>
> Only if the conflict matrix is
> 1. Dense.
> 2. Bidirectional.
>
> Otherwise, you could use sparse bitmaps (in case of 1 not being gtrue) ,
> and/or a lower-triangular bitmatrix (in case of 2 not being true).
I don't think we're using a lower triangular bitmap at this point;
see "mirror_conflicts" in global.c
jeff