Use ARMv8 CRC32 instructions for SkOpts::hash().

Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can roll.

perf.skia.org charts we want to watch: https://perf.skia.org/#5490

Seach for compute_hash in these logs to see the difference:
baseline: https://luci-milo.appspot.com/swarming/task/30ba22f3dfe30e10/steps/nanobench/0/stdout
trybot: https://luci-milo.appspot.com/swarming/task/30bbc406cbf62d10/steps/nanobench/0/stdout

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot

Committed: https://skia.googlesource.com/skia/+/78559a78f9d3e6444f8c0c9443696699703d6531

[mtklein_C, 2016-08-19 12:52:55]

Description was changed from

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

BUG=skia:
==========

to

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
==========

[mtklein_C, 2016-08-19 12:56:09]

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

[commit-bot: I haz the power, 2016-08-19 12:56:19]

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

[mtklein_C, 2016-08-19 13:01:05]

The CQ bit was unchecked by mtklein@chromium.org

[mtklein_C, 2016-08-19 13:08:18]

mtklein@chromium.org changed reviewers:
+ msarett@google.com

[mtklein_C, 2016-08-19 13:29:38]

Description was changed from

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
==========

to

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

perf.skia.org charts we want to watch: https://perf.skia.org/#5490

Seach for compute_hash in these logs to see the difference:
baseline:
https://luci-milo.appspot.com/swarming/task/30ba22f3dfe30e10/steps/nanobench/...
trybot:
https://luci-milo.appspot.com/swarming/task/30bbc406cbf62d10/steps/nanobench/...

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
==========

[msarett, 2016-08-19 13:47:11]

lgtm

[mtklein_C, 2016-08-22 15:15:03]

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

[commit-bot: I haz the power, 2016-08-22 15:15:05]

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, 2016-08-22 15:39:51]

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

[commit-bot: I haz the power, 2016-08-22 15:39:52]

Dry run: This issue passed the CQ dry run.

[mtklein_C, 2016-08-22 15:52:36]

The CQ bit was checked by mtklein@chromium.org

[mtklein_C, 2016-08-22 15:52:36]

The patchset sent to the CQ was uploaded after l-g-t-m from msarett@google.com
Link to the patchset: https://codereview.chromium.org/2260823002/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2016-08-22 15:52:45]

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, 2016-08-22 15:53:47]

Description was changed from

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

perf.skia.org charts we want to watch: https://perf.skia.org/#5490

Seach for compute_hash in these logs to see the difference:
baseline:
https://luci-milo.appspot.com/swarming/task/30ba22f3dfe30e10/steps/nanobench/...
trybot:
https://luci-milo.appspot.com/swarming/task/30bbc406cbf62d10/steps/nanobench/...

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
==========

to

==========
Use ARMv8 CRC32 instructions for SkOpts::hash().

For large inputs, this runs ~11x faster than Murmur3.
My bench drops from 1µs to 88ns.

Like x86-64, this runs fastest if we work in 24 byte chunks.  16 byte chunks
run at about 0.75x this speed, 8 byte chunks at about 0.4x (which would still
be about 5x faster than Murmur3).

This'll require plumbing support for opts_crc32 into Chrome first before it can
roll.

perf.skia.org charts we want to watch: https://perf.skia.org/#5490

Seach for compute_hash in these logs to see the difference:
baseline:
https://luci-milo.appspot.com/swarming/task/30ba22f3dfe30e10/steps/nanobench/...
trybot:
https://luci-milo.appspot.com/swarming/task/30bbc406cbf62d10/steps/nanobench/...

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2260823002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot

Committed:
https://skia.googlesource.com/skia/+/78559a78f9d3e6444f8c0c9443696699703d6531
==========

[commit-bot: I haz the power, 2016-08-22 15:53:48]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/78559a78f9d3e6444f8c0c9443696699703d6531