[ARM64] Support 128 bit moves and swaps in code generator.

[ARM64] Support 128 bit moves and swaps in code generator.

LOG=N
BUG=v8:6020
Review-Url: https://codereview.chromium.org/2928853002
Cr-Commit-Position: refs/heads/master@{#45928}
Committed: https://chromium.googlesource.com/v8/v8/+/a4cf434f5bf4019373460ffd917697167c212501

[bbudge, 2017-06-07 21:21:16]

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

[commit-bot: I haz the power, 2017-06-07 21:21:24]

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, 2017-06-07 21:33:27]

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

[commit-bot: I haz the power, 2017-06-07 21:33:28]

Dry run: Try jobs failed on following builders:
  v8_linux_nodcheck_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel_ng/bu...)

[bbudge, 2017-06-08 01:59:40]

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

[commit-bot: I haz the power, 2017-06-08 01:59:50]

Dry run: CQ is trying da patch.

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

[bbudge, 2017-06-08 02:00:02]

bbudge@chromium.org changed reviewers:
+ martyn.capewell@arm.com

[commit-bot: I haz the power, 2017-06-08 02:26:19]

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

[commit-bot: I haz the power, 2017-06-08 02:26:20]

Dry run: This issue passed the CQ dry run.

[martyn.capewell, 2017-06-08 08:29:13]

https://codereview.chromium.org/2928853002/diff/1/src/compiler/arm64/code-gen...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/2928853002/diff/1/src/compiler/arm64/code-gen...
src/compiler/arm64/code-generator-arm64.cc:2236: __ st1(src, dst);
I'm not sure this will work - I think ToDoubleRegister returns a D-sized
VRegister, so both sides of this conditional store 64 bits from src to dst, but
with different instructions.

On ARM64, the normal Ldr and Str methods support Q registers, so something like
this might work:
VRegister src = (destination->IsSimd128StackSlot) ? g.ToSimd128Register() :
g.ToDoubleRegister();
__ Str(src, dst);

Alternatively, as the way VRegisters overlay is different in ARM64, the size
modifiers could be applied, eg. src.Q().

[bbudge, 2017-06-08 18:45:11]

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

[commit-bot: I haz the power, 2017-06-08 18:45:16]

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, 2017-06-08 19:10:07]

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

[commit-bot: I haz the power, 2017-06-08 19:10:08]

Dry run: This issue passed the CQ dry run.

[bbudge, 2017-06-08 20:16:59]

https://codereview.chromium.org/2928853002/diff/1/src/compiler/arm64/code-gen...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/2928853002/diff/1/src/compiler/arm64/code-gen...
src/compiler/arm64/code-generator-arm64.cc:2236: __ st1(src, dst);
On 2017/06/08 08:29:13, martyn.capewell wrote:
> I'm not sure this will work - I think ToDoubleRegister returns a D-sized
> VRegister, so both sides of this conditional store 64 bits from src to dst,
but
> with different instructions.
> 
> On ARM64, the normal Ldr and Str methods support Q registers, so something
like
> this might work:
> VRegister src = (destination->IsSimd128StackSlot) ? g.ToSimd128Register() :
> g.ToDoubleRegister();
> __ Str(src, dst);
> 
> Alternatively, as the way VRegisters overlay is different in ARM64, the size
> modifiers could be applied, eg. src.Q().

I forgot that VRegisters have a size. I think your alternative solution is the
only one that would work, as ToSimd128Register calls VRegister::from_code, which
assumes it's a d-register. Done here and below.

[martyn.capewell, 2017-06-09 14:29:51]

lgtm

https://codereview.chromium.org/2928853002/diff/20001/src/compiler/arm64/code...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/2928853002/diff/20001/src/compiler/arm64/code...
src/compiler/arm64/code-generator-arm64.cc:2233: if
(!destination->IsSimd128StackSlot()) {
One minor comment - can you switch these clauses? I'm always distracted by
if/else where the if is inverted.

[bbudge, 2017-06-09 15:55:43]

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

[commit-bot: I haz the power, 2017-06-09 15:55:52]

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, 2017-06-09 16:21:22]

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

[commit-bot: I haz the power, 2017-06-09 16:21:23]

Dry run: This issue passed the CQ dry run.

[bbudge, 2017-06-13 21:24:31]

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

[commit-bot: I haz the power, 2017-06-13 21:24:42]

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 21:58:12]

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

[commit-bot: I haz the power, 2017-06-13 21:58:13]

Dry run: This issue passed the CQ dry run.

[bbudge, 2017-06-13 21:58:48]

The CQ bit was checked by bbudge@chromium.org

[bbudge, 2017-06-13 21:58:49]

The patchset sent to the CQ was uploaded after l-g-t-m from
martyn.capewell@arm.com
Link to the patchset: https://codereview.chromium.org/2928853002/#ps60001
(title: "Rebase.")

[commit-bot: I haz the power, 2017-06-13 21:58:51]

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 22:01:31]

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

[commit-bot: I haz the power, 2017-06-13 22:01:32]

Try jobs failed on following builders:
  v8_presubmit on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/43061)

[bbudge, 2017-06-13 22:11:51]

bbudge@chromium.org changed reviewers:
+ mtrofin@chromium.org

[bbudge, 2017-06-13 22:11:51]

+Mircea, for compiler

[Mircea Trofin, 2017-06-13 22:22:15]

lgtm

[bbudge, 2017-06-13 22:25:11]

The CQ bit was checked by bbudge@chromium.org

[commit-bot: I haz the power, 2017-06-13 22:25:21]

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 22:26:55]

CQ is committing da patch.

Bot data: {"patchset_id": 60001, "attempt_start_ts": 1497392711126250,
"parent_rev": "aea68b5a2601d9a86381d7301515dbc5f9eb4ca7", "commit_rev":
"a4cf434f5bf4019373460ffd917697167c212501"}

[commit-bot: I haz the power, 2017-06-13 22:27:02]

Description was changed from

==========
[ARM64] Support 128 bit moves and swaps in code generator.

LOG=N
BUG=v8:6020
==========

to

==========
[ARM64] Support 128 bit moves and swaps in code generator.

LOG=N
BUG=v8:6020

Review-Url: https://codereview.chromium.org/2928853002
Cr-Commit-Position: refs/heads/master@{#45928}
Committed:
https://chromium.googlesource.com/v8/v8/+/a4cf434f5bf4019373460ffd917697167c2...
==========

[commit-bot: I haz the power, 2017-06-13 22:27:04]

Committed patchset #4 (id:60001) as
https://chromium.googlesource.com/v8/v8/+/a4cf434f5bf4019373460ffd917697167c2...