On 2013-09-20 16:47:24 +0200, Andres Freund wrote:
> I think we should go through the various implementations and make sure
> they are actual compiler barriers and then change the documented policy.
From a quick look
* S_UNLOCK for PPC isn't a compiler barrier
* S_UNLOCK for MIPS isn't a compiler barrier
* I don't know enough about unixware (do we still support that as a
platform even) to judge
* True64 Alpha I have no clue about
* PA-RISCs tas() might not be a compiler barrier for !GCC
* PA-RISCs S_UNLOCK might not be a compiler barrier
* HP-UX !GCC might not
* IRIX 5 seems to be a compiler barrier
* SINIX - I don't care
* AIX PPC - compiler barrier
* Sun - TAS is implemented in external assembly, normal function call, compiler barrier
* Win(32|64) - compiler barrier
* Generic S_UNLOCK *NOT* necessarily a compiler barrier.
Ok, so I might have been a bit too optimistic...
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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