[turbofan] Fix deopt loop in out-of-bounds string element access.

[turbofan] Fix deopt loop in out-of-bounds string element access.

We need to check the KeyedLoadIC state to guard against potential
deoptimization loops due to out-of-bounds accesses, because the IC
system uses the MEGAMORPHIC state to also signal that there was an
out-of-bounds access already.

R=jarin@chromium.org

Committed: https://crrev.com/6c5fa8b49e5f8c3371ce34118933ea70468b375a
Cr-Commit-Position: refs/heads/master@{#40525}

[Benedikt Meurer, 2016-10-24 09:20:35]

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

[commit-bot: I haz the power, 2016-10-24 09:20:39]

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

[Jarin, 2016-10-24 09:22:03]

lgtm

[Benedikt Meurer, 2016-10-24 09:23:22]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-10-24 09:23:27]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-10-24 09:23:29]

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, 2016-10-24 09:37:48]

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

[commit-bot: I haz the power, 2016-10-24 09:37:49]

Try jobs failed on following builders:
  v8_linux64_avx2_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel_ng/buil...)
  v8_linux64_avx2_rel_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel_ng_trig...)

[Benedikt Meurer, 2016-10-24 09:49:03]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-10-24 09:49:03]

The patchset sent to the CQ was uploaded after l-g-t-m from jarin@chromium.org
Link to the patchset: https://codereview.chromium.org/2443893002/#ps20001
(title: "REBASE")

[commit-bot: I haz the power, 2016-10-24 09:49:08]

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, 2016-10-24 10:32:17]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-17 22:10:44]

Description was changed from

==========
[turbofan] Fix deopt loop in out-of-bounds string element access.

We need to check the KeyedLoadIC state to guard against potential
deoptimization loops due to out-of-bounds accesses, because the IC
system uses the MEGAMORPHIC state to also signal that there was an
out-of-bounds access already.

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

to

==========
[turbofan] Fix deopt loop in out-of-bounds string element access.

We need to check the KeyedLoadIC state to guard against potential
deoptimization loops due to out-of-bounds accesses, because the IC
system uses the MEGAMORPHIC state to also signal that there was an
out-of-bounds access already.

R=jarin@chromium.org

Committed: https://crrev.com/6c5fa8b49e5f8c3371ce34118933ea70468b375a
Cr-Commit-Position: refs/heads/master@{#40525}
==========

[commit-bot: I haz the power, 2016-11-17 22:10:45]

Patchset 2 (id:??) landed as
https://crrev.com/6c5fa8b49e5f8c3371ce34118933ea70468b375a
Cr-Commit-Position: refs/heads/master@{#40525}