This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: PATCH: Add pause intrinsic
On Wed, May 25, 2011 at 3:26 AM, Andrew Haley <aph@redhat.com> wrote:
> On 05/24/2011 07:28 PM, H.J. Lu wrote:
>
>> This patch implements pause intrinsic suggested by Andi. ?OK
>> for trunk?
>
> What does "full memory barrier" here mean?
>
> +@table @code
> +@item void __builtin_ia32_pause (void)
> +Generates the @code{pause} machine instruction with full memory barrier.
> +@end table
>
> There a memory clobber, but no barrier instruction AFAICS. ?The
> doc needs to explain it a bit better.
>
There are read/load memory barrier, write/store memory barrier and full/general
memory barrier. You can find them at
http://www.kernel.org/doc/Documentation/memory-barriers.txt
Should I include a pointer to it?
--
H.J.