On Wed, 30 Oct 2024 19:02:05 GMT, Coleen Phillimore <cole...@openjdk.org> wrote:
>> src/hotspot/share/runtime/continuationFreezeThaw.cpp line 1411: >> >>> 1409: // zero out fields (but not the stack) >>> 1410: const size_t hs = oopDesc::header_size(); >>> 1411: oopDesc::set_klass_gap(mem, 0); >> >> Why, bug fix or cleanup? > > This might confuse the change for JEP 450 since with CompactObjectHeaders > there's no klass_gap, so depending on which change goes first, there will be > conditional code here. Good question though, it looks like we only ever want > to copy the payload of the object. If I recall correctly this was a bug where one of the stackChunk fields was allocated in that gap, but since we didn't zeroed it out it would start with some invalid value. I guess the reason why we are not hitting this today is because one of the fields we do initialize (sp/bottom/size) is being allocated there, but with the new fields I added to stackChunk that is not the case anymore. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/21565#discussion_r1823580273
