[ast] Mark temporaries as maybe-assigned by default.

[ast] Mark temporaries as maybe-assigned by default.

This is in order to prevent accidental bugs in desugarings.

R=adamk@chromium.org
BUG=v8:5636
Review-Url: https://codereview.chromium.org/2693313002
Cr-Commit-Position: refs/heads/master@{#43237}
Committed: https://chromium.googlesource.com/v8/v8/+/503ad143cc659d7be196219f366681b26500890f

[neis, 2017-02-15 13:39:24]

Description was changed from

==========
[parsing] Mark temporaries as maybe-assigned by default.

This is in order to prevent accidental bugs in desugarings.

R=adamk@chromium.org
BUG=v8:5636
==========

to

==========
[ast] Mark temporaries as maybe-assigned by default.

This is in order to prevent accidental bugs in desugarings.

R=adamk@chromium.org
BUG=v8:5636
==========

[neis, 2017-02-15 13:44:33]

https://codereview.chromium.org/2693313002/diff/1/src/parsing/parser.cc
File src/parsing/parser.cc (right):

https://codereview.chromium.org/2693313002/diff/1/src/parsing/parser.cc#newco...
src/parsing/parser.cc:2994: Token::ASSIGN,
factory()->NewVariableProxy(PromiseVariable()),
This was a bug because we potentially assign twice to the promise variable. 
With this CL, the change from INIT to ASSIGN is purely cosmetic since the
temporary is now already marked as assigned.

[neis, 2017-02-15 13:48:46]

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

[commit-bot: I haz the power, 2017-02-15 13:48:55]

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, 2017-02-15 14:15:42]

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

[commit-bot: I haz the power, 2017-02-15 14:15:43]

Dry run: This issue passed the CQ dry run.

[adamk, 2017-02-15 19:03:59]

lgtm, but I wonder if we can tighten up the API a bit more.

https://codereview.chromium.org/2693313002/diff/1/src/ast/scopes.h
File src/ast/scopes.h (right):

https://codereview.chromium.org/2693313002/diff/1/src/ast/scopes.h#newcode213
src/ast/scopes.h:213: // Only pass kNotAssigned if you know what you are doing.
Not sure this comment is helpful. If this is dangerous enough, should the
version that takes a maybe_assigned argument be private?

[neis, 2017-02-16 09:20:04]

Good suggestion, done.

[neis, 2017-02-16 09:22:25]

The CQ bit was checked by neis@chromium.org

[neis, 2017-02-16 09:22:25]

The patchset sent to the CQ was uploaded after l-g-t-m from adamk@chromium.org
Link to the patchset: https://codereview.chromium.org/2693313002/#ps20001
(title: "Make the powerful variant private.")

[commit-bot: I haz the power, 2017-02-16 09:22:31]

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, 2017-02-16 09:57:05]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1487236945587790,
"parent_rev": "754bb9f98e1bf7dc7710bb54d7e9e999e6ee0d7e", "commit_rev":
"503ad143cc659d7be196219f366681b26500890f"}

[commit-bot: I haz the power, 2017-02-16 09:57:10]

Description was changed from

==========
[ast] Mark temporaries as maybe-assigned by default.

This is in order to prevent accidental bugs in desugarings.

R=adamk@chromium.org
BUG=v8:5636
==========

to

==========
[ast] Mark temporaries as maybe-assigned by default.

This is in order to prevent accidental bugs in desugarings.

R=adamk@chromium.org
BUG=v8:5636

Review-Url: https://codereview.chromium.org/2693313002
Cr-Commit-Position: refs/heads/master@{#43237}
Committed:
https://chromium.googlesource.com/v8/v8/+/503ad143cc659d7be196219f366681b2650...
==========

[commit-bot: I haz the power, 2017-02-16 09:57:11]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/503ad143cc659d7be196219f366681b2650...