RFR(M): 8238759: Clones should always keep the base pointer

[Nils Eliasson]

Hi Roman,

Thanks for the review!

// Nils


On 2020-02-28 19:19, Roman Kennke wrote:
> Hi Nils,
>
> This is a welcome change. We've been using the base in Shenandoah and
> required to pull this out of the interior address. This change makes
> this more robust.
>
> The change looks good.
>
> Thanks,
> Roman
>
>> This patch changes how clone uses arraycopy nodes. Normal arraycopy
>> nodes have the base pointer as src. Arraycopys used for cloning have an
>> interior pointer as src, pointing at where the copy should start. It's
>> not ideal that the arraycopy node is used differently, and it introduces
>> extra complexity when the base pointer is needed at a later stage.
>>
>> This patch changes clones to have the base in the src field, and puts
>> the offset to the where we want to start copy, in the pos field.
>>
>> This patch also changes shenandoah code.
>>
>> https://bugs.openjdk.java.net/browse/JDK-8238759
>> http://cr.openjdk.java.net/~neliasso/8238759/webrev.01/
>>
>> Please review,
>> Nils Eliasson
>>