RFR: 8252752: Clear card table for old regions during scan in G1 [v2]

[Thomas Schatzl]

On Fri, 25 Sep 2020 11:17:12 GMT, Ivan Walulya <iwalulya at openjdk.org> wrote:

>> Thomas Schatzl has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Comments by ayang, kbarrett, iwalulya
>
> src/hotspot/share/gc/g1/g1CollectedHeap.cpp line 3956:
> 
>> 3954:     }
>> 3955:
>> 3956:     rem_set()->complete_evac_phase(true /* has_more_than_one_evacuation_phase */);
> 
> I think it would be cleaner with a local variable:
> bool has_more_than_one_evacuation_phase = true;
> rem_set()->complete_evac_phase(has_more_than_one_evacuation_phase);
> 
> Instead of the comment, same with remember_already_scanned_cards comment above

I kept it as is as this is the common hotspot style for "documenting" flag parameters, and this suggestion does not
seem better to me.

> src/hotspot/share/gc/g1/g1CardTable.hpp line 107:
> 
>> 105:   inline size_t mark_region_dirty(size_t start_card_index, size_t num_cards);
>> 106:
>> 107:   // Mark the given range of cards to "which". All of these cards must be Dirty.
> 
> Maybe change the comment to "Mark the given range of dirty cards as..." or the function name to "mark_dirty_to"

I think I fixed that.

-------------

PR: https://git.openjdk.java.net/jdk/pull/343