RFR: 8220411: Remove ScavengeRootsInCode=0 code

[coleen.phillimore at oracle.com]

This is nice.  Shouldn't you remove ScavengeRootsInCode from 
globals.hpp?  As a diagnostic command, I think it goes into the table in 
arguments.cpp?
Thanks,
Coleen


On 3/11/19 6:26 AM, Stefan Karlsson wrote:
> Updated webrev after some offline feedback from ErikÖ:
>
>  http://cr.openjdk.java.net/~stefank/8220411/webrev.02.delta
>  http://cr.openjdk.java.net/~stefank/8220411/webrev.02
>
> - I've removed can_be_constant and updated the code where it was used.
> - Removed and replaced check_oop with oopDesc::is_oop_or_null checks.
>
> Thanks,
> StefanK
>
> On 2019-03-11 09:57, Stefan Karlsson wrote:
>> Hi all,
>>
>> Please review this patch to remove code that checks and acts upon 
>> ScavengeRootsInCode=0.
>>
>> http://cr.openjdk.java.net/~stefank/8220411/webrev.01/
>> https://bugs.openjdk.java.net/browse/JDK-8220411
>>
>> Since a while now, we have not supported -XX:ScavengeRootsInCode=0, 
>> and the code actively sets it to 1 if the user passes in 0. This 
>> patch removes the actual code, there's another RFE to deal with 
>> changing the argument handling to explicitly not support that the 
>> flag is set to 0. See: JDK-8144954.
>>
>> My main motivation for this patch is to get rid of some of the usages 
>> of CollectedHeap::is_scavengable. The intention is that later patches 
>> will completely remove that function.
>>
>> Thanks,
>> StefanK