ARM port consolidation

[Magnus Ihse Bursie]

 From a build perspective, it would certainly simplify things if we have 
just a single port, so I'm in favour of this proposal.

/Magnus

On 2018-06-05 06:24, David Holmes wrote:
> Hi Bob,
>
> Looping in porters-dev, aarch32-port-dev and aarch64-port-dev.
>
> I think this is a good idea.
>
> Thanks,
> David
>
> On 5/06/2018 6:34 AM, Bob Vandette wrote:
>> During the JDK 9 time frame, Oracle open sourced its 32-bit and 64-bit
>> ARM ports and contributed them to OpenJDK.  These ports have been 
>> used for
>> years in the embedded and mobile market, making them very stable and
>> having the benefit of a single source base which can produce both 32 and
>> 64-bit binaries.  The downside of this contribution is that it resulted
>> in two 64-bit ARM implementations being available in OpenJDK.
>>
>> I'd like to propose that we eliminate one of the 64-bit ARM ports and
>> encourage everyone to enhance and support the remaining 32 and 64 bit
>> ARM ports. This would avoid the creation of yet another port for 
>> these chip
>> architectures.  The reduction of competing ports will allow everyone
>> to focus their attention on a single 64-bit port rather than diluting
>> our efforts.  This will result in a higher quality and a more performant
>> implementation.
>>
>> The community at large (especially RedHat, BellSoft, Linaro and Cavium)
>> have done a great job of enhancing and keeping the AArch64 port up to
>> date with current and new Hotspot features.  As a result, I propose that
>> we standardize the 64-bit ARM implementation on this port.
>>
>> If there are no objections, I will file a JEP to remove the 64-bit ARM
>> port sources that reside in jdk/open/src/hotspot/src/cpu/arm
>> along with any build logic.  This will leave the Oracle contributed
>> 32-bit ARM port and the AArch64 64-bit ARM port.
>>
>> Let me know what you all think,
>> Bob Vandette
>>
>>