RFR: 8251850: Simplify ResourceMark constructors using delegation

[Thomas Schatzl]

Hi,

On 17.08.20 04:24, Kim Barrett wrote:
>> On Aug 15, 2020, at 8:31 AM, Kim Barrett <kim.barrett at oracle.com> wrote:
>>
>>> On Aug 14, 2020, at 10:29 PM, Kim Barrett <kim.barrett at oracle.com> wrote:
>>>
>>> Please review this simplification of the constructors for ResourceMark,
>>> accomplished using delegating constructors.
>>>
>>> Also made the constructors "explicit" and the class non-copyable.
>>>
>>> CR:
>>> https://bugs.openjdk.java.net/browse/JDK-8251850
>>>
>>> Webrev:
>>> https://cr.openjdk.java.net/~kbarrett/8251850/open.00/
>>>
>>> Testing:
>>> mach5 tier1
>>
>> I should have looked further along in resourceArea.hpp. All the
>> changes I made to ResourceMark? DeoptResourceMark should have similar
>> changes made to it.
>>
>> Well, I have a first round of comments from the ResourceMark changes.  I can
>> take those into account for DeoptResourceMark.
> 
> This ended up engendering a fairly substantial revision.  I've taken at
> least some of Thomas's comments into account along the way.
> 
> Changed ResourceMark and DeoptResourceMark to share ResourceMarkImpl, which
> provides most of the implementation of both, eliminating the copy-paste-modify
> "reuse" that used to be there.
> 
> Moved all of the state capture and rollback support into ResourceArea. The
> mark objects include a captured state object and pass that back to the
> ResourceArea when doing rollbacks.
> 
> Cleaned up the _nesting checking.
> 
> Removed nonsensical ResourceArea::_warned.
> 
> Maybe I should change the bug summary from
> "Simplify ResourceMark constructors using delegation"
> to something like
> "Refactor ResourceMark and DeoptResourceMark for better code sharing"
> 

Please do.

> New webrevs:
> full: https://cr.openjdk.java.net/~kbarrett/8251850/open.01/
> incr: https://cr.openjdk.java.net/~kbarrett/8251850/open.01.inc/
> 
> Testing:
> mach5 tier1-3
> local hotspot:tier1 with -XX:+UseMallocOnly
> local hotspot:tier1 with -XX:+ZapResourceArea
> 
> Note that compiler/loopopts/TestDeepGraphVerifyIterativeGVN.java times out
> when run with -XX:+UseMallocOnly, with or without these changes.
> 
> 

   looks good.

Thomas