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Re: Mainline space problem


James E Wilson wrote:

What I said, in both previous messages, is that we have too
many pseudo regs.  The common case is a small enough number of pseudos
such that the quadratic memory allocation here isn't a problem.

I absolutely agree that the problem is too many pseudo-registers. There is no justification for the large number we see here.

When you have performance of N**2/K

increasing K by a small factor is likely to be much less
significant than reducing N or the 2. Now it is true that using
a sparse matrix representation would indeed reduce the 2, but
I agree with JW that this would likely introduce unacceptable
overhead.


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