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

Alejandro E Murillo alejandro.murillo at oracle.com
Tue Jun 23 21:11:15 UTC 2015

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.
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.

I'm working on getting this info on an external wiki



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