RFR: JDK-8202016: Use obj+offset in interpreter array access

[Roman Kennke]

Thanks for the reviews, Andrew!

Roman

> On 14/05/18 12:34, Roman Kennke wrote:
>> Am 14.05.2018 um 13:19 schrieb Andrew Dinn:
>    . . .
>>> Well, that x86 code change looks ok/ish/ -- although the need to reload
>>> from the stack is a tad disappointing.
>>>
>>> However, I am left wondering why this is not a problem on other
>>> architectures? Indeed, looking at AArch64 I believe it is actually a
>>> serious headache.
>>
>> It is, and I have a solution here:
>> cr.openjdk.java.net/~rkennke/interp_primitives_aarch64/webrev.0
> 
> Yuck, how repulsive :]
> 
>> I will propose this for upstream soon.
> 
> Ok, so ack the original x86 change.
> 
>> For AArch64 it will basically reshuffle address calculation from
>> currently (base + index) + disp (which we can't resolve) to base +
>> (index + disp) which we can.
>>
>> The alternative would be to explicitely drag the base_obj through all
>> the BarrierSetAssembler calls. So far I could live without it (x86 and
>> aarch64).
> Yes, even more repulsive, I guess.
> 
> regards,
> 
> 
> Andrew Dinn
> -----------
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