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From: john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice)
Newsgroups: comp.parallel
Subject: CM-2 SIMD question
Message-ID: <12515@hubcap.clemson.edu>
Date: 8 Jan 91 13:49:05 GMT
Sender: fpst@hubcap.clemson.edu
Organization: University of New Mexico, Albuquerque, NM
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Approved: parallel@hubcap.clemson.edu

I have a SIMD question motivated by the CM-2.  We are doing finite
difference calculations on a simple structured grid.  It is trivial to
port our code to the CM-2 to do the difference stencil since it is
inherently a SIMD type problem.  However, different nodes in our mesh
use different equations of state.  Some are tabular, some are
analytic, some are iterative.  Clearly you can't perform all these
calculations in lock step.  So, I assume we have to turn off all processors
except those using a specific equation of state, do the EOS calculations for 
those nodes, and then turn those processors off and turn on those for the next
EOS, etc... until we have exhausted all the types of EOS we need.  Is there
a better way to do this?


John K. Prentice
Amparo Corporation
john@unmfys.unm.edu