[turbofan] Inline ReturnReceiver builtin into TurboFan.

[turbofan] Inline ReturnReceiver builtin into TurboFan.

Builtins::kReturnReceiver is used for the Symbol.iterator function on
iterators, and just returns the iterator itself. For example, for-of
or yield* with a generator will first call generator[Symbol.iterator](),
which simply returns the generator itself. Inlining this particular
builtin into TurboFan is trivial and avoids that call completely,
enabling more possibilities for LoadElimination and EscapeAnalysis
to get rid of even more checks in common generator code.

BUG=v8:6344, v8:6351, v8:6354
R=jgruber@chromium.org

Review-Url: https://codereview.chromium.org/2938683002
Cr-Commit-Position: refs/heads/master@{#45927}
Committed: https://chromium.googlesource.com/v8/v8/+/aea68b5a2601d9a86381d7301515dbc5f9eb4ca7

[Benedikt Meurer, 2017-06-13 19:17:50]

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

[commit-bot: I haz the power, 2017-06-13 19:18:00]

Dry run: CQ is trying da patch.

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

[Benedikt Meurer, 2017-06-13 19:18:26]

Hey Jakob,

Here's another pretty obvious one :-)
Please take a look.

Thanks,
Benedikt

[jgruber, 2017-06-13 19:29:25]

lgtm

[Benedikt Meurer, 2017-06-13 19:29:44]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2017-06-13 19:29:47]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2017-06-13 19:29:57]

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, 2017-06-13 19:47:55]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1497382187333140, "parent_rev":
"223a6f63ea7fba9eabc6e740ef1eb8f0554f9556", "commit_rev":
"aea68b5a2601d9a86381d7301515dbc5f9eb4ca7"}

[commit-bot: I haz the power, 2017-06-13 19:48:21]

Description was changed from

==========
[turbofan] Inline ReturnReceiver builtin into TurboFan.

Builtins::kReturnReceiver is used for the Symbol.iterator function on
iterators, and just returns the iterator itself. For example, for-of
or yield* with a generator will first call generator[Symbol.iterator](),
which simply returns the generator itself. Inlining this particular
builtin into TurboFan is trivial and avoids that call completely,
enabling more possibilities for LoadElimination and EscapeAnalysis
to get rid of even more checks in common generator code.

BUG=v8:6344,v8:6351,v8:6354
R=jgruber@chromium.org
==========

to

==========
[turbofan] Inline ReturnReceiver builtin into TurboFan.

Builtins::kReturnReceiver is used for the Symbol.iterator function on
iterators, and just returns the iterator itself. For example, for-of
or yield* with a generator will first call generator[Symbol.iterator](),
which simply returns the generator itself. Inlining this particular
builtin into TurboFan is trivial and avoids that call completely,
enabling more possibilities for LoadElimination and EscapeAnalysis
to get rid of even more checks in common generator code.

BUG=v8:6344,v8:6351,v8:6354
R=jgruber@chromium.org

Review-Url: https://codereview.chromium.org/2938683002
Cr-Commit-Position: refs/heads/master@{#45927}
Committed:
https://chromium.googlesource.com/v8/v8/+/aea68b5a2601d9a86381d7301515dbc5f9e...
==========

[commit-bot: I haz the power, 2017-06-13 19:48:22]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/aea68b5a2601d9a86381d7301515dbc5f9e...