[turbofan] Some strength reduction on Smi/HeapObject checks.

[turbofan] Some strength reduction on Smi/HeapObject checks.

Let the SimplifiedOperatorReducer perform some strength reduction for
certain CheckTaggedSigned and CheckTaggedPointer inputs (reusing the
existing logic for ObjectIsSmi).

R=jarin@chromium.org
BUG=v8:5141
Committed: https://crrev.com/c30b854aa32cf1b242523b565eb19f397f6cb55c
Cr-Commit-Position: refs/heads/master@{#37167}

[Benedikt Meurer, 2016-06-22 07:03:52]

Hey Jaro,

Here's some initial check optimization (essentially what worked for ObjectIsSmi
already).
Please take a look.

Thanks,
Benedikt

[Jarin, 2016-06-22 07:07:55]

lgtm

[Benedikt Meurer, 2016-06-22 07:48:54]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-06-22 07:48:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2080703006/1

[commit-bot: I haz the power, 2016-06-22 07:50:42]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-22 07:52:28]

Description was changed from

==========
[turbofan] Some strength reduction on Smi/HeapObject checks.

Let the SimplifiedOperatorReducer perform some strength reduction for
certain CheckTaggedSigned and CheckTaggedPointer inputs (reusing the
existing logic for ObjectIsSmi).

R=jarin@chromium.org
BUG=v8:5141
==========

to

==========
[turbofan] Some strength reduction on Smi/HeapObject checks.

Let the SimplifiedOperatorReducer perform some strength reduction for
certain CheckTaggedSigned and CheckTaggedPointer inputs (reusing the
existing logic for ObjectIsSmi).

R=jarin@chromium.org
BUG=v8:5141

Committed: https://crrev.com/c30b854aa32cf1b242523b565eb19f397f6cb55c
Cr-Commit-Position: refs/heads/master@{#37167}
==========

[commit-bot: I haz the power, 2016-06-22 07:52:29]

Patchset 1 (id:??) landed as
https://crrev.com/c30b854aa32cf1b242523b565eb19f397f6cb55c
Cr-Commit-Position: refs/heads/master@{#37167}