From: Marcus Shawcroft <marcus.shawcroft@arm.com>
To: gcc-patches@gcc.gnu.org
Subject: Re: [PATCH] Fix for PR55492 : __atomic_load doesn't match ACQUIRE memory model
Date: Fri, 30 Nov 2012 09:37:00 -0000 [thread overview]
Message-ID: <50B87DE7.70803@arm.com> (raw)
In-Reply-To: <CAD57uCc0hVb740SKkdLJf_BQtE=xHJ126zxNtbBeXHCjUn2LGA@mail.gmail.com>
On 29/11/12 15:42, Yvan Roux wrote:
> Hi,
>
> on ARMv7, the code generated for the __atomic_load builtins in the
> __ATOMIC_ACQUIRE memory model, puts a memory barrier before the load, whereas
> the semantic of the acquire memory model implies a barrier after.
>
> The issue seems to be in expand_atomic_load which puts a memory fence before
> the load in any memory model. The attached patch fixes the problem.
>
> Thanks,
> Yvan
>
The same issue exists in the 4.7 branch.
Can the fix be back ported?
/Marcus
next prev parent reply other threads:[~2012-11-30 9:35 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-29 15:42 Yvan Roux
2012-11-29 17:01 ` Andrew MacLeod
2012-11-29 17:10 ` Yvan Roux
2012-11-30 9:37 ` Marcus Shawcroft [this message]
2012-11-30 10:15 ` Yvan Roux
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