Ephemerons are based around WeakMember which may just be null at the
time the pair is considered for liveness. Bail out of marking for null
keys, as they write barrier would anyways make the value strong when
marking the key.
Bug: chromium:1056170
Change-Id: If8775a370824b88fc67fa479a0c0893985fbf5f4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2692571
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72714}
Cppgc exposes EphemeronPair that contains a WeakMember key and a Member
value and can be used to denote ephemeron semantics in the standalone
library.
Tracing EphemeronPairs goes through TraceEphemeron that is exposed on
the api for the blink usecase.
Bug: chromium:1056170
Change-Id: I9fbaa284fa2034248cdf36ea8b0cd5be6a55f676
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2467842
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70525}