[turbofan] Broaden checkpoint elimination on returns.

[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
Committed: https://crrev.com/a757a62bf5106086250e61eb3a17db888c8a37e3
Cr-Commit-Position: refs/heads/master@{#37480}

[Michael Starzinger, 2016-07-01 13:24:57]

Description was changed from

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholy owned by the return. This also alleviates a
problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
==========

to

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
==========

[Jarin, 2016-07-01 13:41:59]

Neat solution! lgtm.

[Michael Starzinger, 2016-07-01 13:49:45]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2016-07-01 13:49:51]

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, 2016-07-01 13:51:59]

Description was changed from

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
==========

to

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
==========

[commit-bot: I haz the power, 2016-07-01 13:51:59]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-01 13:53:57]

Description was changed from

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747
==========

to

==========
[turbofan] Broaden checkpoint elimination on returns.

This makes the elimination of checkpoints flowing effect-wise into nodes
having the {Return} operator more permissive. We can cut out checkpoints
even when they are not wholly owned by the return. This also alleviates
a problem where TCO no longer applies.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-624747
BUG=chromium:624747

Committed: https://crrev.com/a757a62bf5106086250e61eb3a17db888c8a37e3
Cr-Commit-Position: refs/heads/master@{#37480}
==========

[commit-bot: I haz the power, 2016-07-01 13:53:58]

Patchset 1 (id:??) landed as
https://crrev.com/a757a62bf5106086250e61eb3a17db888c8a37e3
Cr-Commit-Position: refs/heads/master@{#37480}