[serializer] ensure that immortal immovable roots are correctly deserialized.

[serializer] ensure that immortal immovable roots are correctly deserialized.

Immortal immovable roots must be allocated on the first page of the space.
If serializing the root list exceeds the first page, immortal immovable root
objects might end up outside of the first page. That could cause missing
write barriers.

We now iterate the root list twice. The first time we only serialize immortal
immovable root objects. The second time we serialize the rest.

R=mstarzinger@chromium.org

Committed: https://crrev.com/6e8958fff43be37eee4def68a061ab6fb32b7542
Cr-Commit-Position: refs/heads/master@{#34859}

[Michael Starzinger, 2016-03-17 12:27:29]

LGTM.

https://codereview.chromium.org/1811913002/diff/1/src/snapshot/serializer.cc
File src/snapshot/serializer.cc (left):

https://codereview.chromium.org/1811913002/diff/1/src/snapshot/serializer.cc#...
src/snapshot/serializer.cc:100: Object** roots =
isolate()->heap()->roots_array_start();
Woot! I love this, this was one of the last remaining places that references the
roots array directly IIRC. I think this enables one of my cleanups I had in mind
for a long time. Love it!

[Yang, 2016-03-17 12:49:32]

The CQ bit was checked by yangguo@chromium.org

[commit-bot: I haz the power, 2016-03-17 12:49:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1811913002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1811913002/1

[commit-bot: I haz the power, 2016-03-17 13:16:03]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-17 13:16:29]

Description was changed from

==========
[serializer] ensure that immortal immovable roots are correctly deserialized.

Immortal immovable roots must be allocated on the first page of the space.
If serializing the root list exceeds the first page, immortal immovable root
objects might end up outside of the first page. That could cause missing
write barriers.

We now iterate the root list twice. The first time we only serialize immortal
immovable root objects. The second time we serialize the rest.

R=mstarzinger@chromium.org
==========

to

==========
[serializer] ensure that immortal immovable roots are correctly deserialized.

Immortal immovable roots must be allocated on the first page of the space.
If serializing the root list exceeds the first page, immortal immovable root
objects might end up outside of the first page. That could cause missing
write barriers.

We now iterate the root list twice. The first time we only serialize immortal
immovable root objects. The second time we serialize the rest.

R=mstarzinger@chromium.org

Committed: https://crrev.com/6e8958fff43be37eee4def68a061ab6fb32b7542
Cr-Commit-Position: refs/heads/master@{#34859}
==========

[commit-bot: I haz the power, 2016-03-17 13:16:31]

Patchset 1 (id:??) landed as
https://crrev.com/6e8958fff43be37eee4def68a061ab6fb32b7542
Cr-Commit-Position: refs/heads/master@{#34859}