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Re: [PATCH, i386]: Implement atomic_fetch_sub
On 2012-08-03 08:01, Uros Bizjak wrote:
> On Fri, Aug 3, 2012 at 4:40 PM, Richard Henderson <email@example.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?
Yes, since it'll have the same effect on the bits.