RFR: 8166276: Refactor gen_process_roots to allow simpler fix for 8165949

[Mikael Gerdin]

Hi Stefan,


On 2016-09-20 11:08, Stefan Johansson wrote:
> Hi all,
>
> While working on JDK-8165949 [0] I realized that gen_process_roots
> needed to be cleaned/split up to allow it to be fixed. This work had in
> big parts already been done as part of an enhancement [1] that never got
> pushed. That enhancement included another cleanup as well but I have
> split it out to only include the necessary part in this fix. It splits
> gen_process_roots into two different versions, one used for young
> collections and one for old. This make the two methods much easier to
> follow and removes some special cases. I will post a second review for
> the actual bug-fix.
>
> Webrev:
> http://cr.openjdk.java.net/~sjohanss/8166276/hotspot.00/

Overall I think this looks good but it might be a good idea to have a 
look at the comment just above the definition of enum ScanningOption, it 
describes concepts which you are removing (such as not_older_gens)

/Mikael

>
> Subtask:
> https://bugs.openjdk.java.net/browse/JDK-8166276
>
> Testing:
> * JTREG tests locally
> * RBT on HS-gc tier 2-4
>
> Thanks,
> Stefan
>
> [0] https://bugs.openjdk.java.net/browse/JDK-8165949
> [1] https://bugs.openjdk.java.net/browse/JDK-8072809