Speed up clearing of old to new slots in dead objects.

Speed up clearing of old to new slots in dead objects.

Since we clear invalid slots eagerly, there is no need to check if a slot is a valid slot.

BUG=chromium:578883
LOG=NO

Committed: https://crrev.com/4526365f5355ebe06edfb32c1944adb0e1c6f019
Cr-Commit-Position: refs/heads/master@{#34898}

[ulan, 2016-03-18 14:19:42]

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

[ulan, 2016-03-18 14:19:42]

PTAL

https://codereview.chromium.org/1817523002/diff/1/src/heap/mark-compact.cc
File src/heap/mark-compact.cc (left):

https://codereview.chromium.org/1817523002/diff/1/src/heap/mark-compact.cc#ol...
src/heap/mark-compact.cc:2973: return object->IsValidSlot(offset);
This is the main change.

[Hannes Payer (out of office), 2016-03-18 14:52:42]

lgtm

[ulan, 2016-03-18 14:59:01]

The CQ bit was checked by ulan@chromium.org

[commit-bot: I haz the power, 2016-03-18 14:59:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1817523002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1817523002/1

[commit-bot: I haz the power, 2016-03-18 15:02:25]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-03-18 15:02:26]

Try jobs failed on following builders:
  v8_linux64_asan_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_asan_rel/builds/...)
  v8_linux_mips64el_compile_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_mips64el_compile_r...)
  v8_linux_nodcheck_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel/build...)

[ulan, 2016-03-18 15:04:31]

The CQ bit was checked by ulan@chromium.org

[ulan, 2016-03-18 15:04:31]

The patchset sent to the CQ was uploaded after l-g-t-m from hpayer@chromium.org
Link to the patchset: https://codereview.chromium.org/1817523002/#ps20001
(title: "fix compile")

[commit-bot: I haz the power, 2016-03-18 15:04:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1817523002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1817523002/20001

[commit-bot: I haz the power, 2016-03-18 15:27:43]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-03-18 15:28:23]

Description was changed from

==========
Speed up clearing of old to new slots in dead objects.

Since we clear invalid slots eagerly, there is no need to check if a slot is a
valid slot.

BUG=chromium:578883
LOG=NO
==========

to

==========
Speed up clearing of old to new slots in dead objects.

Since we clear invalid slots eagerly, there is no need to check if a slot is a
valid slot.

BUG=chromium:578883
LOG=NO

Committed: https://crrev.com/4526365f5355ebe06edfb32c1944adb0e1c6f019
Cr-Commit-Position: refs/heads/master@{#34898}
==========

[commit-bot: I haz the power, 2016-03-18 15:28:24]

Patchset 2 (id:??) landed as
https://crrev.com/4526365f5355ebe06edfb32c1944adb0e1c6f019
Cr-Commit-Position: refs/heads/master@{#34898}