[ic] Iterations slow with mv_matchlimit incrementations

[Grant]

I have a somewhat complex chunk of IC code about 500 lines long.  If I
set the mv_matchlimit of the main loop to a small number, each
iteration takes less than a second to execute.  However, as I increase
the mv_matchlimit, each iteration takes longer to execute until it's
quite slow.  I've been over my code again and again but I can't find a
cause for this behavior.  The only clue I have is that each iteration
executes much faster when the loop is almost done with all of its
iterations.

I'm wondering if the problem is "under the hood" of IC.  Does this
scenario ring a bell for anyone?

Thanks,
Grant