WebSocket frame masking: use SIMD for ARM

WebSocket frame masking: use SIMD for ARM

WebSocket frame masking has been using SIMD on X86 for GCC and Clang for
a while. Now that Chrome no longer supports disabling ARM Neon (SIMD)
instructions at runtime, we can also perform the same optimisation for
ARM.

I have verified that this change causes a 128-bit vector XOR instruction
to be used when compiling for ARM7, and a good-quality fallback when
compiling for ARM6.

BUG=539259
Review-Url: https://codereview.chromium.org/2941453002
Cr-Commit-Position: refs/heads/master@{#478966}
Committed: https://chromium.googlesource.com/chromium/src/+/813f94f9d2cb7e696795053bc920276ff15d5ba4

[Adam Rice, 2017-06-13 02:40:47]

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

[Adam Rice, 2017-06-13 02:40:59]

ricea@chromium.org changed reviewers:
+ tyoshino@chromium.org

[commit-bot: I haz the power, 2017-06-13 02:41:11]

Dry run: 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, 2017-06-13 04:41:28]

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

[commit-bot: I haz the power, 2017-06-13 04:41:28]

Dry run: This issue passed the CQ dry run.

[tyoshino (SeeGerritForStatus), 2017-06-13 06:43:48]

lgtm

[Adam Rice, 2017-06-13 11:27:56]

The CQ bit was checked by ricea@chromium.org

[commit-bot: I haz the power, 2017-06-13 11:28:01]

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, 2017-06-13 11:31:58]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1497353276269500, "parent_rev":
"ae1f454f8d4a04265809c76e61e227d0a370008f", "commit_rev":
"813f94f9d2cb7e696795053bc920276ff15d5ba4"}

[commit-bot: I haz the power, 2017-06-13 11:32:11]

Description was changed from

==========
WebSocket frame masking: use SIMD for ARM

WebSocket frame masking has been using SIMD on X86 for GCC and Clang for
a while. Now that Chrome no longer supports disabling ARM Neon (SIMD)
instructions at runtime, we can also perform the same optimisation for
ARM.

I have verified that this change causes a 128-bit vector XOR instruction
to be used when compiling for ARM7, and a good-quality fallback when
compiling for ARM6.

BUG=539259
==========

to

==========
WebSocket frame masking: use SIMD for ARM

WebSocket frame masking has been using SIMD on X86 for GCC and Clang for
a while. Now that Chrome no longer supports disabling ARM Neon (SIMD)
instructions at runtime, we can also perform the same optimisation for
ARM.

I have verified that this change causes a 128-bit vector XOR instruction
to be used when compiling for ARM7, and a good-quality fallback when
compiling for ARM6.

BUG=539259

Review-Url: https://codereview.chromium.org/2941453002
Cr-Commit-Position: refs/heads/master@{#478966}
Committed:
https://chromium.googlesource.com/chromium/src/+/813f94f9d2cb7e696795053bc920...
==========

[commit-bot: I haz the power, 2017-06-13 11:32:12]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/813f94f9d2cb7e696795053bc920...