<<On Tue, 16 Jan 2001 19:10:10 -0800, Alfred Perlstein <[EMAIL PROTECTED]> said:
> Just wondering, can't you use 'LOCK addl' and then use 'LOCK addc'?
> add longword, add longword with carry? I know it would be pretty
> ugly, but it should work, no?
The two bus cycles are independent, so there is a race condition.
OTOH, it's a fairly *unlikely* race condition, and the worst thing
that can happen is statistics that are obviously off by four billion.
(The race only occurs when there is a carry out of the low-order
longword, which is to say, once in every 2**32 operations.)
-GAWollman
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