RFR JDK-8059510 Compact symbol table layout inside shared archive

[Jiangli Zhou]

Hi Gerard,

Please see the updated webrev: 
http://cr.openjdk.java.net/~jiangli/8059510/webrev.03/.

Thanks,
Jiangli

On 10/21/2014 02:57 PM, Jiangli Zhou wrote:
> Hi Gerard,
>
> On 10/21/2014 02:32 PM, Gerard Ziemski wrote:
>>
>> On 10/21/2014 1:45 PM, Jiangli Zhou wrote:
>>>
>>> There are pros and cons for both dynamically and statically 
>>> allocating the _shared_table. Dynamically allocating the 
>>> _shared_table as you suggested adds overhead of the memory 
>>> allocation and the overhead of the extra NULL check when the 
>>> _shared_table is in use. When doing optimization, we try to have the 
>>> least overhead for the fast case, so we could make the fast case 
>>> faster (that's when CDS is used).
>>>
>>> Maybe we could make _shared_table.lookup() inlined and reduce the 
>>> overhead of the function call when CDS is not used. 
>>
>> I think that would be OK, though it will require a reader of the code 
>> to follow the call through to find out it's cheap NOP when CDS is 
>> off, unless we add a nice comment here?
>
> I'll add some comments. Thanks for the suggestion.
>
> Thanks,
> Jiangli
>
>>
>>
>> cheers
>>
>