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Re: [PATCH, i386]: Implement atomic_fetch_sub
On Fri, Aug 3, 2012 at 4:40 PM, Richard Henderson <rth@redhat.com> wrote:
> On 2012-08-03 01:51, Uros Bizjak wrote:
>> The same reasoning goes for dynamic negation: for neg %eax,%eax value
>> 0x80000000 stays the same, but we have changed (x)sub to an (x)add in
>> the code stream.
>
> So? Did you think the xadd will trap?
No, but can we ignore the fact that we changed xsub -0x80000000, mem
to xadd -0x080000000, mem?
Uros.