[turbofan] Recognize and optimize flooring integer division.

[turbofan] Recognize and optimize flooring integer division.

Recognize the special

  NumberFloor(NumberDivide(lhs, rhs))

subgraph in TypedOptimization, where both lhs and rhs are in the
Unsigned32 range, and the result is a PlainNumber, and replace the
NumberFloor with a NumberToUint32 truncation.

This could be done in a cleaner way if we have a dedicated type for all
double values in the Unsigned32 range, but that would complicate the
type system quite a bit.

R=jarin@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2614663002
Cr-Commit-Position: refs/heads/master@{#42063}
Committed: https://chromium.googlesource.com/v8/v8/+/2a60fd49db2d787f0dd6a7a731485011ec89d35f

[Benedikt Meurer, 2017-01-04 10:00:07]

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

[commit-bot: I haz the power, 2017-01-04 10:00:18]

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

[Jarin, 2017-01-04 10:04:17]

lgtm

[Benedikt Meurer, 2017-01-04 10:10:58]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2017-01-04 10:11:01]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2017-01-04 10:11:03]

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, 2017-01-04 10:24:49]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1483524661919060, "parent_rev":
"a8b16f44242e701cb9030b86835b58fa7593f4d6", "commit_rev":
"2a60fd49db2d787f0dd6a7a731485011ec89d35f"}

[commit-bot: I haz the power, 2017-01-04 10:24:52]

Description was changed from

==========
[turbofan] Recognize and optimize flooring integer division.

Recognize the special

  NumberFloor(NumberDivide(lhs, rhs))

subgraph in TypedOptimization, where both lhs and rhs are in the
Unsigned32 range, and the result is a PlainNumber, and replace the
NumberFloor with a NumberToUint32 truncation.

This could be done in a cleaner way if we have a dedicated type for all
double values in the Unsigned32 range, but that would complicate the
type system quite a bit.

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

to

==========
[turbofan] Recognize and optimize flooring integer division.

Recognize the special

  NumberFloor(NumberDivide(lhs, rhs))

subgraph in TypedOptimization, where both lhs and rhs are in the
Unsigned32 range, and the result is a PlainNumber, and replace the
NumberFloor with a NumberToUint32 truncation.

This could be done in a cleaner way if we have a dedicated type for all
double values in the Unsigned32 range, but that would complicate the
type system quite a bit.

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

Review-Url: https://codereview.chromium.org/2614663002
Cr-Commit-Position: refs/heads/master@{#42063}
Committed:
https://chromium.googlesource.com/v8/v8/+/2a60fd49db2d787f0dd6a7a731485011ec8...
==========

[commit-bot: I haz the power, 2017-01-04 10:24:53]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/2a60fd49db2d787f0dd6a7a731485011ec8...