[jmm-dev] Will the real memory read barrier please stand up?
stephan.diestelhorst at arm.com
Mon Nov 24 15:21:42 UTC 2014
On Sunday 23 November 2014 23:58:50 Doug Lea wrote:
> This is a [LoadLoad|LoadStore] fence, also known as
> a "load acquire" fence, which is sometimes (including
> inside hotspot) just called a "load fence" because it is the
> only kind of Load* fence that is ever wanted.
Doug, you are the second person to say that. Is that just common wisdom
or am I missing a fundamental reason, here? Or are all the other
constructs strong enough to not requiring plain LoadLoad? Not really,
since a simpe, non-pointer consumer could still have their flag / data
loads reordered. Or is it rather because every consumer will eventually
produce data (that should be ordered behind the data read if it were
derived from it though)?
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