[aarch64-port-dev ] RFR: 8129426: aarch64: add support for PopCount in C2

[Alejandro E Murillo]

On 6/24/2015 1:44 PM, Edward Nevill wrote:
> On Wed, 2015-06-24 at 12:54 -0600, Alejandro E Murillo wrote:
>> On 6/24/2015 7:36 AM, Edward Nevill wrote:
>>> On Tue, 2015-06-23 at 15:11 -0600, Alejandro E Murillo wrote:
>>>> On 6/23/2015 7:51 AM, Edward Nevill wrote:
>>>>> On Tue, 2015-06-23 at 11:32 +0100, Andrew Dinn wrote:
>>>>>> On 23/06/15 11:10, Andrew Haley wrote:
>>>>>>> On 22/06/15 17:14, Andrew Dinn wrote:
>>>>>>>> . . .
>>>>>>>> Well, you might not want to take this risk and instead add an explicit
>>>>>>>> zero of the upper half. But I think we need to be clear what risk we are
>>>>>>>> taking.
>>>>>>> It's this: if we don't explicitly zero the upper half we'll have to
>>>>>>> audit all the code which might present a sign-extended value (instead
>>>>>>> of a zero-extended one) in a register that's supposed to contain a
>>>>>>> jint.
>>>>>> Ok, let's play safe. If Ed tweaks the patch to zero the upper word we
>>>>>> can always revise that later if/when we decide we are feeling lucky.
>>>>>>
>>>>> OK. New webrev at
>>>>>
>>>>> http://cr.openjdk.java.net/~enevill/8129426/webrev.02/
>>>>>
>>>>> All the best,
>>>>> Ed.
>>>>>
>>>>>
>>>> Hi,
>>>> to be consistent with similar integrations and to avoid potential
>>>> merging problems,
>>>> going forward please work with  the hs-rt repo for this kind of changes,
>>>> as Volker has been doing.
>>> Hi Alejandro,
>>>
>>> I have rebased the patch on hs-rt. New webrev
>>>
>>> http://cr.openjdk.java.net/~enevill/8129426/webrev.03/
>>>
>>> Does it look OK to push?
>>>
>>> Thanks,
>>> Ed.
>>>
>> Apologies, I thought you had already pushed that to jdk9/dev,
>> but it turns out you had pushed 8129551 , no this one.
>>
>> If this is a follow up to the previous push into jdk9/dev (8129551)
>> or somewhat related, then it's probably better if you pushed
>> this one  to jdk9/dev as well, as to avoid any possible conflict
>> when we merge jdk9/dev with jdk9/hs. If they are completely
>> independent then go ahead and push it to hs-rt, after review of course.
> OK, I was confused when you suggested it should be pushed to hs-rt, since the change is adding PopCount to C2.
>
> Should I base it on hs-comp and move the review over to hotspot-compiler-dev?
>
> All the best,
> Ed.
>
>
As I said, I didn't double checked and thought that was for the
push you had done into jdk9/dev
yes,  this one looks more appropriate for hs-comp.
Depending on the change, going forward, push to the
appropriate hotspot group repo (hs-rt or hs-comp) not to jdk9/dev

cheers

-- 
Alejandro