RFR: 8228692: BitMap::reallocate might not clear some bits

[Kim Barrett]

> On May 26, 2020, at 9:55 AM, stefan.johansson at oracle.com wrote:
> 
> Hi Kim,
> 
> On 2020-05-22 00:36, Kim Barrett wrote:
>> Please review this change to BitMap reallocation that ensures all
>> newly added bits are cleared when requested.  Previously, there were
>> circumstances where some might not be.  Includes a new gtest for the
>> specific issue.
>> This change also includes a fix for JDK-8235714.  Contrary to previous
>> comments and bug updates, it was not fixed by JDK-8241581 after all.
>> This was noticed while testing the change for JDK-8228692.
>> CR:
>> https://bugs.openjdk.java.net/browse/JDK-8228692
>> https://bugs.openjdk.java.net/browse/JDK-8235714
>> Webrev:
>> https://cr.openjdk.java.net/~kbarrett/8228692/open.00/
> Looks good!

Thanks.

> Thanks,
> Stefan
>> Testing:
>> mach5 tier1
>> Local (linux-x64) BitMap tests, including the new test.  The new test
>> (1) failed before the changes, (2) still failed after either one but
>> not both of the fix for relocate and the fix for count_one_bits, (3)
>> and passes with both fixes.