RFR (S): Ensure BitMaps clearing is done with memset

[Aleksey Shipilev]

On 01/31/2017 07:57 PM, Aleksey Shipilev wrote:
> Not the least reason for this is that we are using per-word cleanup, while we
> should instead use memset. BitMap provides the methods for that, with _large
> suffixes. This patch ensures it:

D'oh. Here it is:
 http://cr.openjdk.java.net/~shade/shenandoah/bitmaps-memset/webrev.01/

Thanks,
-Aleksey