[BLACKBOX] INTEGER arithmetic speed

From: Campbell, Robert (SELEX GALILEO, UK) <robert.d.campbell{([at]})nowhere.xy>
Date: Wed, 19 Oct 2011 15:54:12 +0100

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I have developed an algorithm that uses LONGINTs, and for a particular
input takes
3.5 minutes to run.

I don't always need such large numbers, so I cut-and-pasted an INTEGER
version, which gives the same
results for this input, but takes 5 minutes.


Is this a freak result (maybe to do with cache boundaries or something),
or is it a general
situation that INTEGER arithmetic is 50% slower than LONGINT arithmetic
- the algorithm has a
varied mix of MODs, DIVs, adds, PROCEDURE calls, and assigments to &
from ARRAYs?


Regards

Robert
SELEX Galileo Ltd
Registered Office: Sigma House, Christopher Martin Road, Basildon, Essex SS14 3EL
A company registered in England & Wales. Company no. 02426132
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Received on Wed Oct 19 2011 - 16:54:12 UTC