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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: sub-optimal code for packed boolean arrays -- bug or inherent
 limitation
References: <djnf6f.45b.ln@hunter.axlog.fr>
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Date: 2007-07-04T13:27:17-05:00
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Using -O2 with the old gnat 3.15p on a 3GHz dual core Pentium (but only
programming to use one core) under W2k, I find that the versions with
        B(I) := not B(I);
and
        B(I) := B(I) xor True;
take about 14 nanoseconds, while the version with
        One(i) := True;
        B   := B xor One;
takes about 6.  With 1e9 calls, that's an 8 second difference.