[compiler] Speculate a little more in SpeculativeShiftRightLogical.

[compiler] Speculate a little more in SpeculativeShiftRightLogical.

If the RHS is 0 and we have Smi feedback, speculate that the result (the LHS)
will continue to be in the Unsigned31 range.  This helps us avoid converting
the result to double when merging with Signed32.

R=jarin@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2709423002
Cr-Commit-Position: refs/heads/master@{#43415}
Committed: https://chromium.googlesource.com/v8/v8/+/42ded33b5babdfc96508664382cd80436ad2d563

[neis, 2017-02-23 08:58:40]

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

[commit-bot: I haz the power, 2017-02-23 08:58:47]

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

[neis, 2017-02-23 09:16:14]

Description was changed from

==========
[compiler] Speculate a little more in SpeculativeShiftRightLogical.

If the RHS is 0 and we have Smi feedback, speculate that the result (the LHS)
will continue to be in the Unsigned31 range.

R=jarin@chromium.org
BUG=
==========

to

==========
[compiler] Speculate a little more in SpeculativeShiftRightLogical.

If the RHS is 0 and we have Smi feedback, speculate that the result (the LHS)
will continue to be in the Unsigned31 range.  This helps us avoid converting
the result to double when merging with Signed32.

R=jarin@chromium.org
BUG=
==========

[neis, 2017-02-23 09:16:28]

PTAL

[commit-bot: I haz the power, 2017-02-23 09:19:24]

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

[commit-bot: I haz the power, 2017-02-23 09:19:25]

Dry run: This issue passed the CQ dry run.

[Jarin, 2017-02-24 10:56:05]

lgtm, thanks!

https://codereview.chromium.org/2709423002/diff/1/src/compiler/simplified-low...
File src/compiler/simplified-lowering.cc (right):

https://codereview.chromium.org/2709423002/diff/1/src/compiler/simplified-low...
src/compiler/simplified-lowering.cc:1994: hint <= NumberOperationHint::kSigned32
&&
In other places, we say "if (hint == NumberOperationHint::kSignedSmall || hint
== NumberOperationHint::kSigned32) ...". Could you keep this consistent?

[neis, 2017-02-24 14:16:57]

On 2017/02/24 10:56:05, Jarin wrote:
> lgtm, thanks!
> 
>
https://codereview.chromium.org/2709423002/diff/1/src/compiler/simplified-low...
> File src/compiler/simplified-lowering.cc (right):
> 
>
https://codereview.chromium.org/2709423002/diff/1/src/compiler/simplified-low...
> src/compiler/simplified-lowering.cc:1994: hint <=
NumberOperationHint::kSigned32
> &&
> In other places, we say "if (hint == NumberOperationHint::kSignedSmall || hint
> == NumberOperationHint::kSigned32) ...". Could you keep this consistent?

done

[neis, 2017-02-24 14:17:28]

The CQ bit was checked by neis@chromium.org

[neis, 2017-02-24 14:17:29]

The patchset sent to the CQ was uploaded after l-g-t-m from jarin@chromium.org
Link to the patchset: https://codereview.chromium.org/2709423002/#ps20001
(title: "Address feedback.")

[commit-bot: I haz the power, 2017-02-24 14:17:33]

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, 2017-02-24 14:39:39]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1487945848387730,
"parent_rev": "2ab2bda50d70a3e2af8c1448c0e8420587d4783e", "commit_rev":
"42ded33b5babdfc96508664382cd80436ad2d563"}

[commit-bot: I haz the power, 2017-02-24 14:39:43]

Description was changed from

==========
[compiler] Speculate a little more in SpeculativeShiftRightLogical.

If the RHS is 0 and we have Smi feedback, speculate that the result (the LHS)
will continue to be in the Unsigned31 range.  This helps us avoid converting
the result to double when merging with Signed32.

R=jarin@chromium.org
BUG=
==========

to

==========
[compiler] Speculate a little more in SpeculativeShiftRightLogical.

If the RHS is 0 and we have Smi feedback, speculate that the result (the LHS)
will continue to be in the Unsigned31 range.  This helps us avoid converting
the result to double when merging with Signed32.

R=jarin@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2709423002
Cr-Commit-Position: refs/heads/master@{#43415}
Committed:
https://chromium.googlesource.com/v8/v8/+/42ded33b5babdfc96508664382cd80436ad...
==========

[commit-bot: I haz the power, 2017-02-24 14:39:44]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/42ded33b5babdfc96508664382cd80436ad...