[compiler] Introduce code stubs for abstract equality.

[compiler] Introduce code stubs for abstract equality.

Add EqualStub and NotEqualStub, based on the CodeStubAssembler, and hook
them up with TurboFan and Ignition. The stubs are a full implementation
of abstract equality for ES6 plus the current SIMD.js draft, unlike the
generic version of the CompareIC, which only implements a subset with
funky runtime fallbacks.

Drive-by-fix: Introduce some common helper methods.

R=epertoso@chromium.org
BUG=chromium:592690
LOG=n

Committed: https://crrev.com/8a809501bd229a707cd001a012f2f65f239439be
Cr-Commit-Position: refs/heads/master@{#34806}

[Benedikt Meurer, 2016-03-13 19:07:42]

Hey Enrico,

Here's the last missing TurboFan code stub to fully implement all comparison
operators. I wrote it based on Object::Equals, with appropriate shortcuts (fast
case for Smi) and using a single loop as Object::Equals does. I think there's
some room for improvement here, but let's first stabilize this not fully
optimized version. Once we figure out what to optimize, I want to split it up
into smaller methods.
Please take a look.

Thanks,
Benedikt

[epertoso, 2016-03-14 15:41:38]

TF code stubs are getting harder to read.

Why did you change e.g. lhs_instance_type to lhs_instancetype? Shouldn't we
prefer the first form?

https://codereview.chromium.org/1795793002/diff/1/src/code-stubs.cc
File src/code-stubs.cc (right):

https://codereview.chromium.org/1795793002/diff/1/src/code-stubs.cc#newcode1163
src/code-stubs.cc:1163: for (int32_t i = 0; i < FIRST_NONSTRING_TYPE; ++i) {
Can you just compare and branch to if_lhsisstring and a new label like
lhs_isnotstring instead?

[Benedikt Meurer, 2016-03-14 18:21:00]

On 2016/03/14 15:41:38, epertoso wrote:
> TF code stubs are getting harder to read.

Yeah, a DSL would be awesome at some point :-)

> Why did you change e.g. lhs_instance_type to lhs_instancetype? Shouldn't we
> prefer the first form?

Good question. I did this for consistency, but I'm fine to rename if you prefer
the other form.

[Benedikt Meurer, 2016-03-14 18:21:08]

https://codereview.chromium.org/1795793002/diff/1/src/code-stubs.cc
File src/code-stubs.cc (right):

https://codereview.chromium.org/1795793002/diff/1/src/code-stubs.cc#newcode1163
src/code-stubs.cc:1163: for (int32_t i = 0; i < FIRST_NONSTRING_TYPE; ++i) {
That way you'd need more conditional branches. This indirect branch is most
efficient.

[Benedikt Meurer, 2016-03-15 10:23:42]

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

[commit-bot: I haz the power, 2016-03-15 10:23:50]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1795793002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1795793002/1

[commit-bot: I haz the power, 2016-03-15 10:46:25]

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

[commit-bot: I haz the power, 2016-03-15 10:46:26]

Dry run: This issue passed the CQ dry run.

[epertoso, 2016-03-16 09:27:57]

lgtm

[Benedikt Meurer, 2016-03-16 09:28:37]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-03-16 09:28:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1795793002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1795793002/20001

[commit-bot: I haz the power, 2016-03-16 09:37:01]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-03-16 09:38:01]

Description was changed from

==========
[compiler] Introduce code stubs for abstract equality.

Add EqualStub and NotEqualStub, based on the CodeStubAssembler, and hook
them up with TurboFan and Ignition. The stubs are a full implementation
of abstract equality for ES6 plus the current SIMD.js draft, unlike the
generic version of the CompareIC, which only implements a subset with
funky runtime fallbacks.

Drive-by-fix: Introduce some common helper methods.

R=epertoso@chromium.org
BUG=chromium:592690
LOG=n
==========

to

==========
[compiler] Introduce code stubs for abstract equality.

Add EqualStub and NotEqualStub, based on the CodeStubAssembler, and hook
them up with TurboFan and Ignition. The stubs are a full implementation
of abstract equality for ES6 plus the current SIMD.js draft, unlike the
generic version of the CompareIC, which only implements a subset with
funky runtime fallbacks.

Drive-by-fix: Introduce some common helper methods.

R=epertoso@chromium.org
BUG=chromium:592690
LOG=n

Committed: https://crrev.com/8a809501bd229a707cd001a012f2f65f239439be
Cr-Commit-Position: refs/heads/master@{#34806}
==========

[commit-bot: I haz the power, 2016-03-16 09:38:02]

Patchset 2 (id:??) landed as
https://crrev.com/8a809501bd229a707cd001a012f2f65f239439be
Cr-Commit-Position: refs/heads/master@{#34806}