RFR: 8073093: AARCH64: C2 generates poor code for ByteBuffer accesses

[Andrew Haley]

On 02/16/2015 11:02 AM, Alan Bateman wrote:
> On 14/02/2015 22:10, Dean Long wrote:
>>
>> Even if linux-aarch64 always allows unaligned, checking only for 
>> "aarch64" is not future-proof
>> because it doesn't take the OS into account.  However, I really don't 
>> like having to enumerate
>> all relevant platforms in multiple places in shared code, so I 
>> disagree with the existing code
>> and with perpetuating the pattern.  As long as the decision is in 
>> platform-specific code, a build-time
>> decision may be entirely appropriate.
>
> This alignment test in Bits.java has been there for a long time (JDK 
> 1.4). It's technical debt that hasn't surfaces very often as it's so 
> rare to add architectures. If Unsafe gets a method to test the alignment 
> then it would be great to get Bits changed.

Hopefully it's getting less rare to add architectures!

I'll do that as part of my patch.

Andrew.