7168505: (bf) MappedByteBuffer.load does not load buffer's content into memory

[Rémi Forax]

On 05/15/2012 11:33 AM, Alan Bateman wrote:
> On 15/05/2012 08:07, Rémi Forax wrote:
>>
>> I wonder if it's not better to have a fake method recognized by the 
>> VM for that,
>> because if the VM is smart enough, 'unused' is only used in load() so 
>> it doesn't really escape.
>> A VM/JIT that will generate assembly code for the whole class, by 
>> example when module is installed
>> in module repository, will see that easily.

> I suspect the potential for reflection usage will make it harder for 
> prove.

The VM can deoptimize when you ask for a Field on the static field.
I think Cliff Click has played with something like that.

> I think the solution in the webrev is okay for now, but I agree that 
> we might need something special, like a get method that is known to 
> the VM as having potential side effects.

It will be also easier to write micro-benchmarks that are not reduced to 
a constant.

>
> -Alan

Rémi