[heap] Reland "Make non-atomic markbit operations consistent with atomic ones."

[heap] Reland "Make non-atomic markbit operations consistent with atomic ones."

Now non-atomic color transition operations return a boolean indicating
whether the transition succeeded or not.

This allows to replace color check and transition operations with a
single transition operation. For example:

if (IsWhite(object)) {
  WhiteToBlack(object);
  Foo();
}

becomes

if (WhiteToBlack(object)) {
  Foo();
}

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2863703004
Cr-Commit-Position: refs/heads/master@{#45136}
Committed: https://chromium.googlesource.com/v8/v8/+/db13d8014fa5a6281b78323aae3636d8b5355b67

[ulan, 2017-05-05 12:00:21]

ulan@chromium.org changed reviewers:
+ mlippautz@chromium.org

[ulan, 2017-05-05 12:00:21]

ptal, the fix is in diff between the patch sets.

[ulan, 2017-05-05 12:06:18]

The CQ bit was checked by ulan@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-05-05 12:06:27]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Michael Lippautz, 2017-05-05 12:28:07]

lgtm

[ulan, 2017-05-05 12:29:41]

The CQ bit was checked by ulan@chromium.org

[ulan, 2017-05-05 12:29:42]

The patchset sent to the CQ was uploaded after l-g-t-m from
mlippautz@chromium.org
Link to the patchset: https://codereview.chromium.org/2863703004/#ps40001
(title: "fix dcheck")

[commit-bot: I haz the power, 2017-05-05 12:29:48]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-05 13:14:03]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1493987381803670,
"parent_rev": "919530ac543e9911daae49683498b78f86b142e9", "commit_rev":
"db13d8014fa5a6281b78323aae3636d8b5355b67"}

[commit-bot: I haz the power, 2017-05-05 13:14:09]

Description was changed from

==========
[heap] Reland "Make non-atomic markbit operations consistent with atomic ones."

Now non-atomic color transition operations return a boolean indicating
whether the transition succeeded or not.

This allows to replace color check and transition operations with a
single transition operation. For example:

if (IsWhite(object)) {
  WhiteToBlack(object);
  Foo();
}

becomes

if (WhiteToBlack(object)) {
  Foo();
}

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng
==========

to

==========
[heap] Reland "Make non-atomic markbit operations consistent with atomic ones."

Now non-atomic color transition operations return a boolean indicating
whether the transition succeeded or not.

This allows to replace color check and transition operations with a
single transition operation. For example:

if (IsWhite(object)) {
  WhiteToBlack(object);
  Foo();
}

becomes

if (WhiteToBlack(object)) {
  Foo();
}

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2863703004
Cr-Commit-Position: refs/heads/master@{#45136}
Committed:
https://chromium.googlesource.com/v8/v8/+/db13d8014fa5a6281b78323aae3636d8b53...
==========

[commit-bot: I haz the power, 2017-05-05 13:14:10]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/v8/v8/+/db13d8014fa5a6281b78323aae3636d8b53...