8196485: FromCardCache default card index can cause crashes Summary: The default value of -1 for 32 bit card indices is a regular card value at the border of 2TB heap addresses in the from card cache, so G1 may loose remembered set entries. Extend from card cache entries to 64 bits. Reviewed-by: shade, sjohanss Contributed-by: Thomas Schatzl <thomas.schatzl@oracle.com>, Jarkko Miettinen <jarkko.miettinen@relex.fi>

8180415: Rebuild remembered sets during the concurrent cycle Summary: In general maintain remembered sets of old regions only from the start of the concurrent cycle to the mixed gc they are used, at most until the end of the mixed phase. Reviewed-by: sjohanss, sangheki

8197850: Calculate liveness in regions during marking Reviewed-by: sjohanss, sangheki