[turbofan] Set proper representation for initial arguments length.

[turbofan] Set proper representation for initial arguments length.

The JSArgumentsObject::length representation is initially Smi, so we can
record that on the initial map and use it to optimize the accesses in
TurboFan based on that. Similar for JSSloppyArgumentsObject::caller.

BUG=v8:6262
R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2810333004
Cr-Commit-Position: refs/heads/master@{#44644}
Committed: https://chromium.googlesource.com/v8/v8/+/5eec7df9b319e5b7a8158d82825d61e90a7cfe33

[Benedikt Meurer, 2017-04-13 12:35:59]

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

[commit-bot: I haz the power, 2017-04-13 12:36:05]

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

[Yang, 2017-04-13 12:36:43]

On 2017/04/13 12:35:57, Benedikt Meurer wrote:

lgtm.

[commit-bot: I haz the power, 2017-04-13 13:00:55]

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

[commit-bot: I haz the power, 2017-04-13 13:00:56]

Dry run: This issue passed the CQ dry run.

[Benedikt Meurer, 2017-04-13 13:01:26]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2017-04-13 13:01:34]

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, 2017-04-13 13:03:47]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1492088486229710, "parent_rev":
"c80c0f11f4c14d7ede75b79efccab1d4d1fc86ab", "commit_rev":
"5eec7df9b319e5b7a8158d82825d61e90a7cfe33"}

[commit-bot: I haz the power, 2017-04-13 13:03:52]

Description was changed from

==========
[turbofan] Set proper representation for initial arguments length.

The JSArgumentsObject::length representation is initially Smi, so we can
record that on the initial map and use it to optimize the accesses in
TurboFan based on that. Similar for JSSloppyArgumentsObject::caller.

BUG=v8:6262
R=yangguo@chromium.org
==========

to

==========
[turbofan] Set proper representation for initial arguments length.

The JSArgumentsObject::length representation is initially Smi, so we can
record that on the initial map and use it to optimize the accesses in
TurboFan based on that. Similar for JSSloppyArgumentsObject::caller.

BUG=v8:6262
R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2810333004
Cr-Commit-Position: refs/heads/master@{#44644}
Committed:
https://chromium.googlesource.com/v8/v8/+/5eec7df9b319e5b7a8158d82825d61e90a7...
==========

[commit-bot: I haz the power, 2017-04-13 13:03:54]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/5eec7df9b319e5b7a8158d82825d61e90a7...

[Camillo Bruni, 2017-04-19 12:11:21]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/2825323002/ by cbruni@chromium.org.

The reason for reverting is: Field representation is not preserved.