[turbofan] Also utilize the string length protector.

[turbofan] Also utilize the string length protector.

Utilize the string length protector to deoptimize if the resulting
string length for string addition overflows. This way we generate
less code here and avoid holding on to the lazy frame state, and
thus potentially reduce the number live ranges.

BUG=v8:5267, v8:5404
R=yangguo@chromium.org

Committed: https://crrev.com/ddba89c433170aa4618bc551da4c18327dfb6a81
Cr-Commit-Position: refs/heads/master@{#40909}

[Benedikt Meurer, 2016-11-11 07:55:32]

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

[commit-bot: I haz the power, 2016-11-11 07:55:40]

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

[Yang, 2016-11-11 08:03:59]

On 2016/11/11 07:55:31, Benedikt Meurer wrote:

lgtm.

[Benedikt Meurer, 2016-11-11 08:04:33]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-11-11 08:08:56]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-11-11 08:08:58]

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, 2016-11-11 08:21:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-17 22:29:59]

Description was changed from

==========
[turbofan] Also utilize the string length protector.

Utilize the string length protector to deoptimize if the resulting
string length for string addition overflows. This way we generate
less code here and avoid holding on to the lazy frame state, and
thus potentially reduce the number live ranges.

BUG=v8:5267,v8:5404
R=yangguo@chromium.org
==========

to

==========
[turbofan] Also utilize the string length protector.

Utilize the string length protector to deoptimize if the resulting
string length for string addition overflows. This way we generate
less code here and avoid holding on to the lazy frame state, and
thus potentially reduce the number live ranges.

BUG=v8:5267,v8:5404
R=yangguo@chromium.org

Committed: https://crrev.com/ddba89c433170aa4618bc551da4c18327dfb6a81
Cr-Commit-Position: refs/heads/master@{#40909}
==========

[commit-bot: I haz the power, 2016-11-17 22:30:00]

Patchset 1 (id:??) landed as
https://crrev.com/ddba89c433170aa4618bc551da4c18327dfb6a81
Cr-Commit-Position: refs/heads/master@{#40909}