Request for review(M): 6964776: c2 should ensure the polling page is reachable on 64 bit

[Igor Veresov]

On 3/25/11 5:31 PM, Vladimir Kozlov wrote:
> x86_64.ad:
> + // It does it the polling page is more than disp32 away.
> ---
> // It needs it when polling page is more than disp32 away.

Ah, typo, thanks! Actually I meant "it does _if_ the polling page ..." 
be a continuation of the previous comment line.

>
> Usually predicate is first in instructions definitions.

All fixed and updated.

igor

>
> Vladimir
>
> Igor Veresov wrote:
>> C1 and C2 could only use rip-relative addressing when emitting the
>> page-polling code, which limited the distance from the code cache to
>> the polling page is more than 2G (doesn't fit in a signed 32bit
>> displacement). The solution in this case is to materialize the
>> absolute pointer to the polling page in a register first, as we do on
>> SPARC.
>>
>> Webrev: http://cr.openjdk.java.net/~iveresov/6964776/webrev.00/
>>
>> Thanks,
>> igor