[turbofan] Implicitly emit eager checkpoint at graph building.

[turbofan] Implicitly emit eager checkpoint at graph building.

This makes preparation of eager checkpoints within the graph builder
implicit. Every sub-expression visitation is now guaranteed to emit
valid checkpoints in AstContext.

R=jarin@chromium.org
BUG=v8:5021
Committed: https://crrev.com/74e328efee7995aeee6d568f9d14f9bbc1087100
Cr-Commit-Position: refs/heads/master@{#37368}

[Michael Starzinger, 2016-06-28 14:48:56]

Patchset #11 (id:200001) has been deleted

[Michael Starzinger, 2016-06-28 18:01:00]

PTAL. This should now be ready for prime time.

[Jarin, 2016-06-28 21:21:16]

lgtm. I love it.

Thanks for fixing the bugs!

[Michael Starzinger, 2016-06-29 08:00:15]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2016-06-29 08:00:28]

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, 2016-06-29 08:42:23]

Committed patchset #13 (id:260001)

[commit-bot: I haz the power, 2016-06-29 08:44:51]

Description was changed from

==========
[turbofan] Implicitly emit eager checkpoint at graph building.

This makes preparation of eager checkpoints within the graph builder
implicit. Every sub-expression visitation is now guaranteed to emit
valid checkpoints in AstContext.

R=jarin@chromium.org
BUG=v8:5021
==========

to

==========
[turbofan] Implicitly emit eager checkpoint at graph building.

This makes preparation of eager checkpoints within the graph builder
implicit. Every sub-expression visitation is now guaranteed to emit
valid checkpoints in AstContext.

R=jarin@chromium.org
BUG=v8:5021

Committed: https://crrev.com/74e328efee7995aeee6d568f9d14f9bbc1087100
Cr-Commit-Position: refs/heads/master@{#37368}
==========

[commit-bot: I haz the power, 2016-06-29 08:44:52]

Patchset 13 (id:??) landed as
https://crrev.com/74e328efee7995aeee6d568f9d14f9bbc1087100
Cr-Commit-Position: refs/heads/master@{#37368}

[Michael Starzinger, 2016-06-29 09:18:21]

A revert of this CL (patchset #13 id:260001) has been created in
https://codereview.chromium.org/2104973004/ by mstarzinger@chromium.org.

The reason for reverting is: Causers flaky failures on the waterfall on Mac with
the following error in the builtin QuickSort method:

#
# Fatal error in Zone
# Allocation failed - process out of memory
#.