[turbofan] Remove remaining uses of Class type from the compiler.

[turbofan] Remove remaining uses of Class type from the compiler.

We (mis)used Type::Class to track stable field maps in the past. But
that always more or less unsupport and wrong for various reasons, mostly
because the class types do not really present static information and
thus it is possible to violate fundamental assumptions of the type
system (i.e. intersecting class types and other types produces
"interesting" results).

Now it is possible to finally nuke the class types completely and thus
simplify (and ideally correctify) the type system further.

Note to performance sheriff: We do expect to see some performance
regressions from this change. This is because we do not yet have a sane
replacement mechanism to track known field maps and utilize them during
LoadElimination. This will be accomplished in a follow up CL.

BUG=v8:5270, v8:5267
R=jarin@chromium.org

Committed: https://crrev.com/2b93899057a4c52cf523114b582bbca48b035cb2
Cr-Commit-Position: refs/heads/master@{#39031}

[Benedikt Meurer, 2016-08-31 04:02:37]

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

[commit-bot: I haz the power, 2016-08-31 04:02:54]

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

[Benedikt Meurer, 2016-08-31 04:08:05]

Hey Jaro,

Removing the weird class type completely from the compiler directory. This also
unblocks the TypeGuard CL for LoadElimination.
Please take a look.

Thanks,
Benedikt

[commit-bot: I haz the power, 2016-08-31 04:25:31]

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

[commit-bot: I haz the power, 2016-08-31 04:25:32]

Dry run: This issue passed the CQ dry run.

[Jarin, 2016-08-31 05:41:44]

lgtm

[Benedikt Meurer, 2016-08-31 05:42:17]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-08-31 05:42:22]

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, 2016-08-31 05:44:28]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-31 05:44:46]

Description was changed from

==========
[turbofan] Remove remaining uses of Class type from the compiler.

We (mis)used Type::Class to track stable field maps in the past. But
that always more or less unsupport and wrong for various reasons, mostly
because the class types do not really present static information and
thus it is possible to violate fundamental assumptions of the type
system (i.e. intersecting class types and other types produces
"interesting" results).

Now it is possible to finally nuke the class types completely and thus
simplify (and ideally correctify) the type system further.

Note to performance sheriff: We do expect to see some performance
regressions from this change. This is because we do not yet have a sane
replacement mechanism to track known field maps and utilize them during
LoadElimination. This will be accomplished in a follow up CL.

BUG=v8:5270,v8:5267
R=jarin@chromium.org
==========

to

==========
[turbofan] Remove remaining uses of Class type from the compiler.

We (mis)used Type::Class to track stable field maps in the past. But
that always more or less unsupport and wrong for various reasons, mostly
because the class types do not really present static information and
thus it is possible to violate fundamental assumptions of the type
system (i.e. intersecting class types and other types produces
"interesting" results).

Now it is possible to finally nuke the class types completely and thus
simplify (and ideally correctify) the type system further.

Note to performance sheriff: We do expect to see some performance
regressions from this change. This is because we do not yet have a sane
replacement mechanism to track known field maps and utilize them during
LoadElimination. This will be accomplished in a follow up CL.

BUG=v8:5270,v8:5267
R=jarin@chromium.org

Committed: https://crrev.com/2b93899057a4c52cf523114b582bbca48b035cb2
Cr-Commit-Position: refs/heads/master@{#39031}
==========

[commit-bot: I haz the power, 2016-08-31 05:44:47]

Patchset 1 (id:??) landed as
https://crrev.com/2b93899057a4c52cf523114b582bbca48b035cb2
Cr-Commit-Position: refs/heads/master@{#39031}