[cpp-threads] A question about N2153

[Chris Thomasson]

----- Original Message ----- 
From: "Paul E. McKenney" <paulmck at linux.vnet.ibm.com>
To: "C++ threads standardisation" <cpp-threads at decadentplace.org.uk>
Sent: Wednesday, January 17, 2007 11:20 AM
Subject: Re: [cpp-threads] A question about N2153


> On Wed, Jan 17, 2007 at 08:44:00PM +0200, Peter Dimov wrote:
>> What is the reference implementation of acquire_fence for x86, SPARC RMO,
>> PowerPC, IA-64? I'm guessing (no op), #LoadLoad | #LoadStore, lwsync, mf.
>
> Stupid side question...  Why acquire_fence and release_fence?  This is
> the only group I have come across that uses these.  Where I come from,
> we use the following types:

Well, an acquire_"fence" is like this:

// do your atomic operation here
#StoreLoad | #StoreStore



And a release_"fence" is like this:

#LoadStore | #StoreStore
// do your atomic operation here