[PR65768] Check rtx_cost when propagating constant

[Kugan]

On 29/05/15 07:31, Jeff Law wrote:
> On 05/13/2015 11:46 PM, Kugan wrote:
>> ping?
>>
>> Thanks,
>> Kugan
>>
>> On 15/04/15 17:53, Kugan wrote:
>>> As mentioned in PR65768, ARM gcc generates suboptimal code for constant
>>> Uses in loop. Part of the reason is cprop is undoing what loop invariant
>>> code motion did.
>>>
>>> Zhenqiang posted a patch at to fix this based on rtx costs:
>>> https://gcc.gnu.org/ml/gcc-patches/2014-06/msg01321.html
>>>
>>> I cleaned it up and bootstrapped, regression tested on x86_64-linux-gnu;
>>> no new regressions. Is this OK for trunk?
>>>
>>> Thanks,
>>> Kugan
>>>
>>> gcc/ChangeLog:
>>>
>>> 2015-04-15  Kugan Vivekanandarajah  <kuganv@linaro.org>
>>>         Zhenqiang Chen  <zhenqiang.chen@linaro.org>
>>>
>>>     PR target/65768
>>>     * cprop.c (try_replace_reg): Check cost of constants before
>>> propagating.
> I should have also noted, fresh bootstrap & regression test is needed too.

Thanks Jeff for the comments. I did a fresh bootstrap and regression
testing on x86_64-linux-gnu with no new regression. I will wait for you ACK.

Thanks,
Kugan