RFR: 8201647: Make initial clearing of CHeapBitMap optional

[Per Liden]

Thanks Stuart!

/Per

On 04/17/2018 03:17 PM, Stuart Monteith wrote:
> Not that I'm a reviewer, but that looks good to me.
> 
> On 17 April 2018 at 13:38, Per Liden <per.liden at oracle.com> wrote:
>> CHeapBitMap objects will by default clear the underlying bitmap during
>> construction. In ZGC we don't want mark bitmaps to be cleared on
>> construction, since we instead do this lazily during concurrent marking.
>>
>> This patch adds a "bool clear = true" argument to CHeapBitMap's constructor
>> to be able to opt-out of this behavior.
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8201647
>> Webrev: http://cr.openjdk.java.net/~pliden/8201647/webrev.0
>>
>> /Per