[turbofan] Merge PropertyAccessInfo for compatible field loads.

[turbofan] Merge PropertyAccessInfo for compatible field loads.

For polymorphic loads that refer to the same underlying field, but
differ in either representation or field maps, try harder to merge
them into a simple field load by going to Tagged representation or
throwing away the field maps (this is essentially what Crankshaft
is doing).

R=jarin@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2836893002
Cr-Commit-Position: refs/heads/master@{#44831}
Committed: https://chromium.googlesource.com/v8/v8/+/1c1a884d4f6dbe3c68796f3fd5b46b99aac2b335

[Benedikt Meurer, 2017-04-24 09:03:35]

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

[commit-bot: I haz the power, 2017-04-24 09:03:44]

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, 2017-04-24 09:28:34]

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

[commit-bot: I haz the power, 2017-04-24 09:28:35]

Dry run: This issue passed the CQ dry run.

[Jarin, 2017-04-25 08:20:39]

lgtm

[Benedikt Meurer, 2017-04-25 08:21:10]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2017-04-25 08:21:15]

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, 2017-04-25 08:22:48]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1493108470307360, "parent_rev":
"d081a6f692f0fc7ecbca40f09b07eebbbdb8c43d", "commit_rev":
"1c1a884d4f6dbe3c68796f3fd5b46b99aac2b335"}

[commit-bot: I haz the power, 2017-04-25 08:22:54]

Description was changed from

==========
[turbofan] Merge PropertyAccessInfo for compatible field loads.

For polymorphic loads that refer to the same underlying field, but
differ in either representation or field maps, try harder to merge
them into a simple field load by going to Tagged representation or
throwing away the field maps (this is essentially what Crankshaft
is doing).

R=jarin@chromium.org
BUG=v8:5267
==========

to

==========
[turbofan] Merge PropertyAccessInfo for compatible field loads.

For polymorphic loads that refer to the same underlying field, but
differ in either representation or field maps, try harder to merge
them into a simple field load by going to Tagged representation or
throwing away the field maps (this is essentially what Crankshaft
is doing).

R=jarin@chromium.org
BUG=v8:5267

Review-Url: https://codereview.chromium.org/2836893002
Cr-Commit-Position: refs/heads/master@{#44831}
Committed:
https://chromium.googlesource.com/v8/v8/+/1c1a884d4f6dbe3c68796f3fd5b46b99aac...
==========

[commit-bot: I haz the power, 2017-04-25 08:22:55]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/1c1a884d4f6dbe3c68796f3fd5b46b99aac...