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Re: [PATCH, i386]: Implement atomic_fetch_sub
On Fri, Aug 3, 2012 at 9:24 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Fri, Aug 3, 2012 at 8:40 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
>
>> We can implement atomic_fetch_sub with atomic_fetch_add and inverted
>> operand 2. However, we have to prevent overflows with negation, so
>> only const_int operand 2 is allowed in the expander.
Why do you need to prevent overflows?
Richard.
>> 2012-08-02 Uros Bizjak <ubizjak@gmail.com>
>>
>> PR target/54087
>> * config/i386/sync.md (atomic_fetch_sub<mode>): New expander.
>>
>> Tested on x86_64-pc-linux-gnu {,-m32}.
>>
>> I will wait for a day for possible comments.
>
> Patch attached again, this time with a testcase.
>
> 2012-08-02 Uros Bizjak <ubizjak@gmail.com>
>
> PR target/54087
> * gcc.target/i386/pr54087.c: New test.
>
> Uros.