[regexp] Avoid runtime call on OOB lastIndex values

[regexp] Avoid runtime call on OOB lastIndex values

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365, v8:6344
Review-Url: https://codereview.chromium.org/2863643004
Cr-Commit-Position: refs/heads/master@{#45143}
Committed: https://chromium.googlesource.com/v8/v8/+/2fd1afc0c8128148b74b3d9ff7b39c084c7dd90b

[jgruber, 2017-05-05 15:04:38]

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

[commit-bot: I haz the power, 2017-05-05 15:04:44]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jgruber, 2017-05-05 15:29:59]

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

[jgruber, 2017-05-05 15:31:17]

Description was changed from

==========
[regexp] Avoid runtime call on OOB lastIndex values

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365,v8:6344
==========

to

==========
[regexp] Avoid runtime call on OOB lastIndex values

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365,v8:6344
==========

[Jakob Kummerow, 2017-05-05 15:35:55]

LGTM with a nit.

https://codereview.chromium.org/2863643004/diff/1/src/builtins/builtins-regex...
File src/builtins/builtins-regexp-gen.cc (right):

https://codereview.chromium.org/2863643004/diff/1/src/builtins/builtins-regex...
src/builtins/builtins-regexp-gen.cc:252: CSA_ASSERT(this, IsNumber(last_index));
nit: you can move the IsNumberNormalized check here to avoid duplication.

[commit-bot: I haz the power, 2017-05-05 15:37:31]

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

[commit-bot: I haz the power, 2017-05-05 15:37:32]

Dry run: This issue passed the CQ dry run.

[jgruber, 2017-05-05 15:46:43]

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

[commit-bot: I haz the power, 2017-05-05 15:46:54]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jgruber, 2017-05-05 15:53:33]

https://codereview.chromium.org/2863643004/diff/1/src/builtins/builtins-regex...
File src/builtins/builtins-regexp-gen.cc (right):

https://codereview.chromium.org/2863643004/diff/1/src/builtins/builtins-regex...
src/builtins/builtins-regexp-gen.cc:252: CSA_ASSERT(this, IsNumber(last_index));
On 2017/05/05 15:35:55, Jakob Kummerow wrote:
> nit: you can move the IsNumberNormalized check here to avoid duplication.

I wanted to keep the assert close to relevant code (if you don't mind). The
latest patchset also adds an IsNumberPositive assertion.

[Jakob Kummerow, 2017-05-05 15:55:51]

lgtm

[commit-bot: I haz the power, 2017-05-05 16:17:59]

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

[commit-bot: I haz the power, 2017-05-05 16:18:00]

Dry run: This issue passed the CQ dry run.

[jgruber, 2017-05-05 16:43:00]

The CQ bit was checked by jgruber@chromium.org

[commit-bot: I haz the power, 2017-05-05 16:43:12]

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, 2017-05-05 16:44:45]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1494002580417970,
"parent_rev": "3f4536894ac3001c53256d08d1e85aa442eb0f02", "commit_rev":
"2fd1afc0c8128148b74b3d9ff7b39c084c7dd90b"}

[commit-bot: I haz the power, 2017-05-05 16:44:51]

Description was changed from

==========
[regexp] Avoid runtime call on OOB lastIndex values

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365,v8:6344
==========

to

==========
[regexp] Avoid runtime call on OOB lastIndex values

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365,v8:6344

Review-Url: https://codereview.chromium.org/2863643004
Cr-Commit-Position: refs/heads/master@{#45143}
Committed:
https://chromium.googlesource.com/v8/v8/+/2fd1afc0c8128148b74b3d9ff7b39c084c7...
==========

[commit-bot: I haz the power, 2017-05-05 16:44:52]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/2fd1afc0c8128148b74b3d9ff7b39c084c7...