[WASM] Skip SIMD test values that may result in denormalized numbers.

[WASM] Skip SIMD test values that may result in denormalized numbers.
On ARM Neon at least, denormals flush to zero, which may not match
regular FP behavior.

LOG=N
BUG=v8:4124
Review-Url: https://codereview.chromium.org/2598583002
Cr-Commit-Position: refs/heads/master@{#41895}
Committed: https://chromium.googlesource.com/v8/v8/+/7a6138ae11b7e1108bb3ced923993a3dc2def4eb

[bbudge, 2016-12-21 09:46:21]

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

[commit-bot: I haz the power, 2016-12-21 09:46:31]

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

[bbudge, 2016-12-21 09:56:44]

bbudge@chromium.org changed reviewers:
+ rodolph.perfetta@arm.com, titzer@chromium.org

[bbudge, 2016-12-21 09:57:39]

This is intended to fix test failures on ARM hardware:

https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm%20-%20debug/bu...

[commit-bot: I haz the power, 2016-12-21 10:12:20]

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

[commit-bot: I haz the power, 2016-12-21 10:12:21]

Dry run: This issue passed the CQ dry run.

[titzer, 2016-12-21 10:19:08]

lgtm

https://codereview.chromium.org/2598583002/diff/1/test/cctest/wasm/test-run-w...
File test/cctest/wasm/test-run-wasm-simd.cc (right):

https://codereview.chromium.org/2598583002/diff/1/test/cctest/wasm/test-run-w...
test/cctest/wasm/test-run-wasm-simd.cc:239: float expected = expected_op(*i,
*j);
IIUC, arm does flush-to-zero for sub-normal numbers, so we could make this check
more strict and check against zero.

Can you add a TODO here to that effect?

[bbudge, 2016-12-21 15:03:39]

https://codereview.chromium.org/2598583002/diff/1/test/cctest/wasm/test-run-w...
File test/cctest/wasm/test-run-wasm-simd.cc (right):

https://codereview.chromium.org/2598583002/diff/1/test/cctest/wasm/test-run-w...
test/cctest/wasm/test-run-wasm-simd.cc:239: float expected = expected_op(*i,
*j);
On 2016/12/21 10:19:08, titzer wrote:
> IIUC, arm does flush-to-zero for sub-normal numbers, so we could make this
check
> more strict and check against zero.
> 
> Can you add a TODO here to that effect?

Done.

[bbudge, 2016-12-21 15:03:43]

The CQ bit was checked by bbudge@chromium.org

[bbudge, 2016-12-21 15:03:43]

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/2598583002/#ps20001
(title: "Add a TODO.")

[commit-bot: I haz the power, 2016-12-21 15:03:49]

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, 2016-12-21 15:31:42]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1482332623150920,
"parent_rev": "679b31c21425ecdd86c40a8a02ac131b72f7bc6b", "commit_rev":
"7a6138ae11b7e1108bb3ced923993a3dc2def4eb"}

[commit-bot: I haz the power, 2016-12-21 15:31:45]

Description was changed from

==========
[WASM] Skip SIMD test values that may result in denormalized numbers.
On ARM Neon at least, denormals flush to zero, which may not match
regular FP behavior.

LOG=N
BUG=v8:4124
==========

to

==========
[WASM] Skip SIMD test values that may result in denormalized numbers.
On ARM Neon at least, denormals flush to zero, which may not match
regular FP behavior.

LOG=N
BUG=v8:4124

Review-Url: https://codereview.chromium.org/2598583002
Cr-Commit-Position: refs/heads/master@{#41895}
Committed:
https://chromium.googlesource.com/v8/v8/+/7a6138ae11b7e1108bb3ced923993a3dc2d...
==========

[commit-bot: I haz the power, 2016-12-21 15:31:46]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/7a6138ae11b7e1108bb3ced923993a3dc2d...