Re: RFR (XS): 8212753: Improve oopDesc::forward_to_atomic

On Oct 22, 2018, at 9:02 AM, Thomas Schatzl <thomas.schatzl@oracle.com> wrote:

CR: https://bugs.openjdk.java.net/browse/JDK-8212753 Webrev: http://cr.openjdk.java.net/~tschatzl/8212753/webrev/ Testing: hs-tier1-3

Thanks, Thomas

There’s an additional change to the G1 code here: src/hotspot/share/gc/g1/g1ParScanThreadState.cpp 313 } else if (!obj->is_typeArray()) { which seems unrelated to the described change and unmentioned in the RFR. Is this change intentional here? Is this a measurable optimization? For the CMS-conditionalized asserts in forward_to_atomic, please add a comment that CMS may CAS in a special pseudo-oop value.