commit e7464ad22749d7ca92db1a4a23acad3ebd1f4dfa
author Michael Lippautz <mlippautz@chromium.org> Tue Nov 20 21:18:18 2018
committer Commit Bot <commit-bot@chromium.org> Tue Nov 20 21:18:18 2018
tree 677f2481dd8a3e266cee83595640294bb453c689
parent 38a06f637c42f6970d4efd359b9d91835ca001b7

heap: Avoid scheduling other garbage collections during unified heap

tl;dr: Write barrier elimination in ctors requires white-allocation of
objects.

Longer: Avoid scheduling GC calls during object allocation
(construction) as they would potentially invoke V8 marking steps. Such a
marking step is problematic if the object that is currently being
constructed has already been published as constructors rely on
white-allocation of objects in order to avoid write barriers for
initializing stores.  A call to V8 may trigger a marking step which in
turn may mark an object black if it already has been published.

Bug: 903790, 843903
Change-Id: I9ede36f34f074f76b563601fd4bd1dcb30f561c4
Reviewed-on: https://chromium-review.googlesource.com/c/1341997
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609806}