CRR (M): 7127697: G1: remove dead code after recent concurrent mark changes

[Tony Printezis]

For completeness, here's the final webrev:

http://cr.openjdk.java.net/~tonyp/7127697/webrev.2/

(I included the removal of the mostly_disjoint_range_union() method as I 
didn't hear any argument against doing so)

I'll do a bit more testing on it and push it asap.

Tony

On 04/02/2012 06:42 AM, Tony Printezis wrote:
> John,
>
> Good catch re: copyright notices. Thanks!
>
> Tony
>
> On 03/28/2012 12:57 PM, John Cuthbertson wrote:
>> Hi Tony,
>>
>> I looked at the two new webrevs and they look good. This is a massive 
>> cleanup. The copyrights in bitMap.hpp and bitMap.cpp need updating.
>>
>> JohnC
>>
>> On 3/27/2012 9:34 AM, Tony Printezis wrote:
>>> Bengt,
>>>
>>> Thanks for looking at it. Inline.
>>>
>>> On 03/27/2012 08:19 AM, Bengt Rutisson wrote:
>>>>
>>>> Hi Tony,
>>>>
>>>> It is always difficult to review removed code, but this looks good 
>>>> to me.
>>>
>>> Thanks.
>>>
>>>> I would like to include your second change as well. It would be 
>>>> good to remove BitMap::mostly_disjoint_range_union(). I realize it 
>>>> is a difficult method to re-implement, but leaving it in without 
>>>> any usage will make it break sooner or later anyway. So, better to 
>>>> re-implement it if we ever need it again.
>>>
>>> Well, re-implementing it is a bit of a waste of time. Maybe, it 
>>> could be revived from the hg history...
>>>
>>>> A couple of minor comments:
>>>>
>>>> concurrentMark.cpp
>>>>
>>>> Comment starting on line 2832 needs to be updated now that 
>>>> drainAllSATBBuffers is gone. Maybe the whole comment is irrelevant?
>>>>
>>>> // This note is for drainAllSATBBuffers and the code in between.
>>>> // In the future we could reuse a task to do this work during an
>>>> // evacuation pause (since now tasks are not active and can be claimed
>>>> // during an evacuation pause). This was a late change to the code and
>>>> // is currently not being taken advantage of.
>>>
>>> Thanks for pointing this out. It turns out that the method is 
>>> actually unused now, so it's also gone along with the comment. ;-)
>>>
>>>> heapRegion.hpp
>>>>
>>>> You removed CompleteMarkCSetClaimValue = 6 from enum ClaimValues. 
>>>> Any reason why you did not renumber the entries following it?
>>>
>>> Laziness? :-)
>>>
>>>> In fact, why do the entries have numbers at all since they are 
>>>> starting on 0 and just increasing by 1. That is the default for an 
>>>> enum, right?
>>>
>>> Not sure why it was done this way. It's nice to have the numbers, 
>>> say, during debugging (so you don't have to count to find out what a 
>>> value of '3' means). I left them as is and I renumbered the last three.
>>>
>>> Thanks again for the code review! The new webrevs are here:
>>>
>>> http://cr.openjdk.java.net/~tonyp/7127697/webrev.1/webrev.0.G1CMCleanup/ 
>>>
>>>
>>> http://cr.openjdk.java.net/~tonyp/7127697/webrev.1/webrev.1.G1CMCleanupExtra/ 
>>>
>>>
>>> Tony
>>>
>>>> Bengt
>>>>
>>>> On 2012-03-27 11:29, Tony Printezis wrote:
>>>>> Hi all,
>>>>>
>>>>> I'd like a couple of code reviews for this set of changes:
>>>>>
>>>>> http://cr.openjdk.java.net/~tonyp/7127697/webrev.0/webrev.0.G1CMCleanup/ 
>>>>>
>>>>>
>>>>> which removes lots code from conc mark that was made unreachable 
>>>>> from a recent set of changes. The changes are mostly code removal 
>>>>> with only a very small number of code actually modified.
>>>>>
>>>>> This is an additional proposed change:
>>>>>
>>>>> http://cr.openjdk.java.net/~tonyp/7127697/webrev.0/webrev.1.G1CMCleanupExtra/ 
>>>>>
>>>>>
>>>>> to remove a method from the bitmap class which is not used any 
>>>>> more (it was only used by the code in G1 conc mark that I'm 
>>>>> removing). I'd like some feedback on whether I should go ahead and 
>>>>> remove it or leave it in in case it's used in the future.
>>>>>
>>>>> Tony
>>>>>
>>>>
>>