[turbofan] Introduce a dedicated ConvertTaggedHoleToUndefined operator.

[turbofan] Introduce a dedicated ConvertTaggedHoleToUndefined operator.

Separate ConvertTaggedHoleToUndefined and CheckTaggedHole into two
separate operators, where the former is pure and just turns into
trivial control flow in the EffectControlLinearizer.

R=jarin@chromium.org

Committed: https://crrev.com/e61bd68ede0a8687ba2c8f59c8483c9ea1e0ce45
Cr-Commit-Position: refs/heads/master@{#38559}

[Benedikt Meurer, 2016-08-10 13:21:31]

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

[commit-bot: I haz the power, 2016-08-10 13:21:38]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Jarin, 2016-08-10 13:31:00]

lgtm

[Benedikt Meurer, 2016-08-10 13:56:09]

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

[commit-bot: I haz the power, 2016-08-10 13:56:15]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Benedikt Meurer, 2016-08-10 13:57:35]

The CQ bit was unchecked by bmeurer@chromium.org

[Michael Starzinger, 2016-08-10 13:59:36]

mstarzinger@chromium.org changed reviewers:
+ mstarzinger@chromium.org

[Michael Starzinger, 2016-08-10 13:59:37]

LGTM (rubber-stamp of "heap" with one nit).

https://codereview.chromium.org/2236443004/diff/20001/src/heap/heap.cc
File src/heap/heap.cc (right):

https://codereview.chromium.org/2236443004/diff/20001/src/heap/heap.cc#newcod...
src/heap/heap.cc:2632: factory->NewHeapNumber(bit_cast<double>(kHoleNanInt64)),
nit: Please pretenure this heap-number to avoid old-to-new reference.

[Benedikt Meurer, 2016-08-10 14:01:00]

https://codereview.chromium.org/2236443004/diff/20001/src/heap/heap.cc
File src/heap/heap.cc (right):

https://codereview.chromium.org/2236443004/diff/20001/src/heap/heap.cc#newcod...
src/heap/heap.cc:2632: factory->NewHeapNumber(bit_cast<double>(kHoleNanInt64)),
On 2016/08/10 13:59:37, Michael Starzinger wrote:
> nit: Please pretenure this heap-number to avoid old-to-new reference.

Done.

[Benedikt Meurer, 2016-08-10 14:01:05]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-08-10 14:01:06]

The patchset sent to the CQ was uploaded after l-g-t-m from jarin@chromium.org,
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/2236443004/#ps40001
(title: "Address comment")

[commit-bot: I haz the power, 2016-08-10 14:01:13]

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, 2016-08-10 14:59:31]

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

[commit-bot: I haz the power, 2016-08-10 14:59:32]

Try jobs failed on following builders:
  v8_linux_dbg_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_dbg_ng/builds/10740)
  v8_linux_dbg_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_dbg_ng_triggered/b...)

[Benedikt Meurer, 2016-08-10 17:43:57]

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

[Benedikt Meurer, 2016-08-10 17:44:08]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-08-10 17:44:13]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-08-10 17:44:14]

The patchset sent to the CQ was uploaded after l-g-t-m from jarin@chromium.org,
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/2236443004/#ps60001
(title: "Fix verify heap.")

[commit-bot: I haz the power, 2016-08-10 17:44:20]

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, 2016-08-10 19:15:34]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-08-10 19:15:59]

Description was changed from

==========
[turbofan] Introduce a dedicated ConvertTaggedHoleToUndefined operator.

Separate ConvertTaggedHoleToUndefined and CheckTaggedHole into two
separate operators, where the former is pure and just turns into
trivial control flow in the EffectControlLinearizer.

R=jarin@chromium.org
==========

to

==========
[turbofan] Introduce a dedicated ConvertTaggedHoleToUndefined operator.

Separate ConvertTaggedHoleToUndefined and CheckTaggedHole into two
separate operators, where the former is pure and just turns into
trivial control flow in the EffectControlLinearizer.

R=jarin@chromium.org

Committed: https://crrev.com/e61bd68ede0a8687ba2c8f59c8483c9ea1e0ce45
Cr-Commit-Position: refs/heads/master@{#38559}
==========

[commit-bot: I haz the power, 2016-08-10 19:16:01]

Patchset 4 (id:??) landed as
https://crrev.com/e61bd68ede0a8687ba2c8f59c8483c9ea1e0ce45
Cr-Commit-Position: refs/heads/master@{#38559}