From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: Boolean array representation question
Date: 1997/11/22
Date: 1997-11-22T00:00:00+00:00 [thread overview]
Message-ID: <dewar.880207946@merv> (raw)
In-Reply-To: mheaney-ya023680002211970030030001@news.ni.net
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.
next prev parent reply other threads:[~1997-11-22 0:00 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
1997-11-20 0:00 Boolean array representation question Jerry van Dijk
1997-11-20 0:00 ` Matthew Heaney
1997-11-21 0:00 ` John P. Lippiello
1997-11-22 0:00 ` Jerry van Dijk
1997-11-22 0:00 ` Matthew Heaney
1997-11-22 0:00 ` Robert Dewar [this message]
1997-11-23 0:00 ` Geert Bosch
1997-11-24 0:00 ` Larry Kilgallen
1997-11-24 0:00 ` Robert Dewar
1997-11-22 0:00 ` Robert Dewar
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