[turbofan] Eliminate checkpoints before return in common op reducer.

[turbofan] Eliminate checkpoints before return in common op reducer.

This makes sure that we preserve call's tailness even if we have
introduced a loop exit between the call and the return.

BUG=chromium:628773
Committed: https://crrev.com/86110796f6de0013e5ab42509c4e6f72abf38e76
Cr-Commit-Position: refs/heads/master@{#37832}

[Jarin, 2016-07-18 11:19:46]

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

[commit-bot: I haz the power, 2016-07-18 11:19:53]

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

[Jarin, 2016-07-18 11:21:15]

jarin@chromium.org changed reviewers:
+ bmeurer@chromium.org

[Jarin, 2016-07-18 11:21:16]

Could you take a look, please?

[Jarin, 2016-07-18 11:29:41]

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

[commit-bot: I haz the power, 2016-07-18 11:29:53]

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

[Benedikt Meurer, 2016-07-18 11:29:54]

LGTM once comment addressed.

https://codereview.chromium.org/2155123002/diff/1/src/compiler/common-operato...
File src/compiler/common-operator-reducer.cc (right):

https://codereview.chromium.org/2155123002/diff/1/src/compiler/common-operato...
src/compiler/common-operator-reducer.cc:312:
NodeProperties::ReplaceEffectInput(node, effect);
You need to say Changed(node) as you changed some input of the node (but you
also need to make sure to allow the optimization below).

[Jarin, 2016-07-18 11:48:53]

https://codereview.chromium.org/2155123002/diff/1/src/compiler/common-operato...
File src/compiler/common-operator-reducer.cc (right):

https://codereview.chromium.org/2155123002/diff/1/src/compiler/common-operato...
src/compiler/common-operator-reducer.cc:312:
NodeProperties::ReplaceEffectInput(node, effect);
On 2016/07/18 11:29:54, Benedikt Meurer wrote:
> You need to say Changed(node) as you changed some input of the node (but you
> also need to make sure to allow the optimization below).

Good catch! Done.

[commit-bot: I haz the power, 2016-07-18 11:51:43]

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

[commit-bot: I haz the power, 2016-07-18 11:51:44]

Dry run: This issue passed the CQ dry run.

[Jarin, 2016-07-18 11:53:17]

The CQ bit was checked by jarin@chromium.org

[commit-bot: I haz the power, 2016-07-18 11:53:22]

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, 2016-07-18 11:55:40]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-07-18 11:57:01]

Description was changed from

==========
[turbofan] Eliminate checkpoints before return in common op reducer.

This makes sure that we preserve call's tailness even if we have
introduced a loop exit between the call and the return.

BUG=chromium:628773
==========

to

==========
[turbofan] Eliminate checkpoints before return in common op reducer.

This makes sure that we preserve call's tailness even if we have
introduced a loop exit between the call and the return.

BUG=chromium:628773

Committed: https://crrev.com/86110796f6de0013e5ab42509c4e6f72abf38e76
Cr-Commit-Position: refs/heads/master@{#37832}
==========

[commit-bot: I haz the power, 2016-07-18 11:57:02]

Patchset 2 (id:??) landed as
https://crrev.com/86110796f6de0013e5ab42509c4e6f72abf38e76
Cr-Commit-Position: refs/heads/master@{#37832}