[asmjs] Do constant folding for I32Asmjs(Div|Rem)S to avoid checks of constant divisors

[asmjs] Do constant folding for I32Asmjs(Div|Rem)S to avoid checks of constant divisors

This change makes the embenchen/copy benchmark a factor of 2 faster and
brings back the performance loss through graph trimming.

R=titzer@chromium.org
CC=bradnelson@chromium.org

Committed: https://crrev.com/0ddddcb8629d456c678c1eeb3c1d1e27b8c426f2
Cr-Commit-Position: refs/heads/master@{#40628}

[ahaas, 2016-10-27 12:05:55]

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

[commit-bot: I haz the power, 2016-10-27 12:05:57]

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

[titzer, 2016-10-27 12:07:42]

Can you add specific tests for these in test/mjsunit/wasm/asm-wasm.js (or a
similar file)?

[titzer, 2016-10-27 12:07:52]

On 2016/10/27 12:07:42, titzer wrote:
> Can you add specific tests for these in test/mjsunit/wasm/asm-wasm.js (or a
> similar file)?

lgtm other than missing test

[commit-bot: I haz the power, 2016-10-27 12:36:12]

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

[commit-bot: I haz the power, 2016-10-27 12:36:13]

Dry run: This issue passed the CQ dry run.

[ahaas, 2016-10-27 14:08:00]

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

[commit-bot: I haz the power, 2016-10-27 14:08:07]

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

[ahaas, 2016-10-27 14:08:55]

On 2016/10/27 at 12:07:52, titzer wrote:
> On 2016/10/27 12:07:42, titzer wrote:
> > Can you add specific tests for these in test/mjsunit/wasm/asm-wasm.js (or a
> > similar file)?
> 
> lgtm other than missing test

PTAL, I added test:
cctest/test-run-wasm/RunWasmCompiled_Int32AsmjsDivS_byzero_const
cctest/test-run-wasm/RunWasmCompiled_Int32AsmjsRemS_byzero_const

[commit-bot: I haz the power, 2016-10-27 14:35:33]

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

[commit-bot: I haz the power, 2016-10-27 14:35:35]

Dry run: This issue passed the CQ dry run.

[bradnelson, 2016-10-27 16:00:09]

bradnelson@chromium.org changed reviewers:
+ bradnelson@chromium.org

[bradnelson, 2016-10-27 16:00:10]

The CQ bit was checked by bradnelson@chromium.org

[bradnelson, 2016-10-27 16:00:10]

lgtm

[bradnelson, 2016-10-27 16:00:10]

The patchset sent to the CQ was uploaded after l-g-t-m from titzer@chromium.org
Link to the patchset: https://codereview.chromium.org/2453343002/#ps20001
(title: "Add tests")

[commit-bot: I haz the power, 2016-10-27 16:00:15]

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

[titzer, 2016-10-27 16:02:20]

lgtm

[commit-bot: I haz the power, 2016-10-27 16:02:29]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-17 22:15:51]

Description was changed from

==========
[asmjs] Do constant folding for I32Asmjs(Div|Rem)S to avoid checks of constant
divisors

This change makes the embenchen/copy benchmark a factor of 2 faster and
brings back the performance loss through graph trimming.

R=titzer@chromium.org
CC=bradnelson@chromium.org
==========

to

==========
[asmjs] Do constant folding for I32Asmjs(Div|Rem)S to avoid checks of constant
divisors

This change makes the embenchen/copy benchmark a factor of 2 faster and
brings back the performance loss through graph trimming.

R=titzer@chromium.org
CC=bradnelson@chromium.org

Committed: https://crrev.com/0ddddcb8629d456c678c1eeb3c1d1e27b8c426f2
Cr-Commit-Position: refs/heads/master@{#40628}
==========

[commit-bot: I haz the power, 2016-11-17 22:15:52]

Patchset 2 (id:??) landed as
https://crrev.com/0ddddcb8629d456c678c1eeb3c1d1e27b8c426f2
Cr-Commit-Position: refs/heads/master@{#40628}