[regexp] Fold repeated assertions

[regexp] Fold repeated assertions

For instance, /\b\b\b\B\B\B/ is folded into the equivalent /\b\B/.

BUG=v8:6126
Review-Url: https://codereview.chromium.org/2768443003
Cr-Commit-Position: refs/heads/master@{#44004}
Committed: https://chromium.googlesource.com/v8/v8/+/c8e4c8b9263b5009716804f06f39225a9dd7fc68

[jgruber, 2017-03-21 14:21:39]

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

[commit-bot: I haz the power, 2017-03-21 14:21:40]

Dry run: 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, 2017-03-21 15:09:42]

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

[commit-bot: I haz the power, 2017-03-21 15:09:43]

Dry run: Try jobs failed on following builders:
  v8_win64_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_win64_rel_ng/builds/24570)
  v8_win64_rel_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_win64_rel_ng_triggered/b...)

[jgruber, 2017-03-21 15:16:54]

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

[commit-bot: I haz the power, 2017-03-21 15:17:03]

Dry run: 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, 2017-03-21 15:41:33]

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

[commit-bot: I haz the power, 2017-03-21 15:41:34]

Dry run: This issue passed the CQ dry run.

[jgruber, 2017-03-21 15:52:48]

jgruber@chromium.org changed reviewers:
+ yangguo@chromium.org

[jgruber, 2017-03-21 15:52:48]

Hi Yang, please take a look. This folds word, line, and input boundary
assertions.

[Yang, 2017-03-22 09:23:38]

On 2017/03/21 15:52:48, jgruber wrote:
> Hi Yang, please take a look. This folds word, line, and input boundary
> assertions.

lgtm.

fwiw \b\B is impossible to match iiuc. So you could match this pattern in
RegExpAlternative::ToNode and return an EndNode with BACK_TRACK.

[jgruber, 2017-03-22 09:27:03]

The CQ bit was checked by jgruber@chromium.org

[commit-bot: I haz the power, 2017-03-22 09:27:11]

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, 2017-03-22 09:28:29]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1490174823974830,
"parent_rev": "da511d3349fbc5f1cbaea804f3082aa2dbf1fe4d", "commit_rev":
"c8e4c8b9263b5009716804f06f39225a9dd7fc68"}

[commit-bot: I haz the power, 2017-03-22 09:28:34]

Description was changed from

==========
[regexp] Fold repeated assertions

For instance, /\b\b\b\B\B\B/ is folded into the equivalent /\b\B/.

BUG=v8:6126
==========

to

==========
[regexp] Fold repeated assertions

For instance, /\b\b\b\B\B\B/ is folded into the equivalent /\b\B/.

BUG=v8:6126

Review-Url: https://codereview.chromium.org/2768443003
Cr-Commit-Position: refs/heads/master@{#44004}
Committed:
https://chromium.googlesource.com/v8/v8/+/c8e4c8b9263b5009716804f06f39225a9dd...
==========

[commit-bot: I haz the power, 2017-03-22 09:28:35]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/c8e4c8b9263b5009716804f06f39225a9dd...