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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: Boolean array representation question
Date: 1997/11/22
Message-ID: <dewar.880207946@merv>#1/1
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Date: 1997-11-22T00:00:00+00:00
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Matthew says

<<If your compiler optimizes for speed, it's going to use the most
time-efficient way to get the value of a component.  For a Boolean, it
makes the most sense to allocate some integral number of storage elements
for each component.  It could be 8, 16, 32, whatever.  The value 8 seems to
be the best compromise between time and space.>>

No, this misses the point. On almost all architectures, the reason for
choosing a component size of 8 is driven by semantic requirements for
independence. FOr a full discussion of the independence issue for
shared variables, see Norman Schulman's thesis on shared variables
(Robert Dewar advisor, NYU, about ten years ago), or for a summary,
read my Ada 9X paper on shared variables.