Introduce {ConstantElementsPair} struct for type safety.

Introduce {ConstantElementsPair} struct for type safety.

This introduces an explicit struct for the communication channel between
the {ArrayLiteral} AST node and the corresponding runtime methods. Those
methods take a pair of {ElementsKind} as well as an array (can either be
a FixedArray or a FixedDoubleArray) of constant values.

For bonus points it also reduces the size of the involved heap object by
one word (i.e. length field of FixedArray not needed anymore).

R=mvstanton@chromium.org

Review-Url: https://codereview.chromium.org/2581683003
Cr-Commit-Position: refs/heads/master@{#41752}
Committed: https://chromium.googlesource.com/v8/v8/+/92b370ee642743d4d795536900da7715c73152c9

[Michael Starzinger, 2016-12-15 12:21:41]

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

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

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

[Michael Starzinger, 2016-12-15 12:25:25]

As for motivation, this is to avoid bugs like these:
https://codereview.chromium.org/2542633002/

[commit-bot: I haz the power, 2016-12-15 12:28:17]

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

[commit-bot: I haz the power, 2016-12-15 12:28:18]

Dry run: Try jobs failed on following builders:
  v8_android_arm_compile_rel on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_android_arm_compile_rel/...)
  v8_linux_arm_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm_rel_ng/builds/...)

[Michael Starzinger, 2016-12-15 13:05:42]

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

[commit-bot: I haz the power, 2016-12-15 13:05:49]

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, 2016-12-15 13:11:58]

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

[commit-bot: I haz the power, 2016-12-15 13:11:59]

Dry run: Try jobs failed on following builders:
  v8_linux64_gyp_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_gyp_rel_ng/build...)
  v8_linux64_gyp_rel_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_gyp_rel_ng_trigg...)

[Michael Starzinger, 2016-12-15 13:22:38]

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

[commit-bot: I haz the power, 2016-12-15 13:22:49]

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, 2016-12-15 13:47:20]

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

[commit-bot: I haz the power, 2016-12-15 13:47:21]

Dry run: This issue passed the CQ dry run.

[mvstanton, 2016-12-16 09:10:18]

LGTM, just one nit.
Thanks for this cleanup!

https://codereview.chromium.org/2581683003/diff/40001/src/objects-printer.cc
File src/objects-printer.cc (right):

https://codereview.chromium.org/2581683003/diff/40001/src/objects-printer.cc#...
src/objects-printer.cc:1315: HeapObject::PrintHeader(os,
"ContstantElementsPair");
Typo here...

[Michael Starzinger, 2016-12-16 09:13:19]

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

[commit-bot: I haz the power, 2016-12-16 09:13:25]

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

[Michael Starzinger, 2016-12-16 09:19:02]

Thanks! Comments addressed. Landing now-ish.

https://codereview.chromium.org/2581683003/diff/40001/src/objects-printer.cc
File src/objects-printer.cc (right):

https://codereview.chromium.org/2581683003/diff/40001/src/objects-printer.cc#...
src/objects-printer.cc:1315: HeapObject::PrintHeader(os,
"ContstantElementsPair");
On 2016/12/16 09:10:18, mvstanton wrote:
> Typo here...

Done.

[commit-bot: I haz the power, 2016-12-16 09:42:44]

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

[commit-bot: I haz the power, 2016-12-16 09:42:44]

Dry run: This issue passed the CQ dry run.

[Michael Starzinger, 2016-12-16 10:03:10]

The CQ bit was checked by mstarzinger@chromium.org

[Michael Starzinger, 2016-12-16 10:03:10]

The patchset sent to the CQ was uploaded after l-g-t-m from
mvstanton@chromium.org
Link to the patchset: https://codereview.chromium.org/2581683003/#ps60001
(title: "Addressed comments.")

[commit-bot: I haz the power, 2016-12-16 10:03:16]

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, 2016-12-16 10:06:45]

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

[commit-bot: I haz the power, 2016-12-16 10:06:46]

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/30765)

[Toon Verwaest, 2016-12-16 10:20:06]

verwaest@chromium.org changed reviewers:
+ verwaest@chromium.org

[Toon Verwaest, 2016-12-16 10:20:06]

hydrogen.cc lgtm

[Michael Starzinger, 2016-12-16 10:21:41]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2016-12-16 10:21:45]

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, 2016-12-16 10:23:26]

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

[commit-bot: I haz the power, 2016-12-16 10:23:30]

Failed to apply patch for src/objects-inl.h:
While running git apply --index -p1;
  error: patch failed: src/objects-inl.h:5809
  error: src/objects-inl.h: patch does not apply

Patch:       src/objects-inl.h
Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index
b1165b3ae7ea74daef4df6ec236d76fdc3b2eaf7..7eefef94ecd4530b4dfe90b88034b39e61ef684c
100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -5809,6 +5809,10 @@ ACCESSORS(Tuple3, value3, Object, kValue3Offset)
 ACCESSORS(ContextExtension, scope_info, ScopeInfo, kScopeInfoOffset)
 ACCESSORS(ContextExtension, extension, Object, kExtensionOffset)
 
+SMI_ACCESSORS(ConstantElementsPair, elements_kind, kElementsKindOffset)
+ACCESSORS(ConstantElementsPair, constant_values, FixedArrayBase,
+          kConstantValuesOffset)
+
 ACCESSORS(JSModuleNamespace, module, Module, kModuleOffset)
 
 ACCESSORS(JSFixedArrayIterator, array, FixedArray, kArrayOffset)

[Michael Starzinger, 2016-12-16 10:27:18]

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

[commit-bot: I haz the power, 2016-12-16 10:27:24]

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, 2016-12-16 10:54:04]

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

[commit-bot: I haz the power, 2016-12-16 10:54:05]

Dry run: This issue passed the CQ dry run.

[Michael Starzinger, 2016-12-16 10:54:58]

The CQ bit was checked by mstarzinger@chromium.org

[Michael Starzinger, 2016-12-16 10:54:59]

The patchset sent to the CQ was uploaded after l-g-t-m from
mvstanton@chromium.org, verwaest@chromium.org
Link to the patchset: https://codereview.chromium.org/2581683003/#ps70001
(title: "Rebased.")

[commit-bot: I haz the power, 2016-12-16 10:55:06]

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, 2016-12-16 10:57:07]

CQ is committing da patch.

Bot data: {"patchset_id": 70001, "attempt_start_ts": 1481885698848720,
"parent_rev": "cb9d0fe7f4789dc5c471fcb092457efc503bd2e4", "commit_rev":
"92b370ee642743d4d795536900da7715c73152c9"}

[commit-bot: I haz the power, 2016-12-16 10:57:14]

Description was changed from

==========
Introduce {ConstantElementsPair} struct for type safety.

This introduces an explicit struct for the communication channel between
the {ArrayLiteral} AST node and the corresponding runtime methods. Those
methods take a pair of {ElementsKind} as well as an array (can either be
a FixedArray or a FixedDoubleArray) of constant values.

For bonus points it also reduces the size of the involved heap object by
one word (i.e. length field of FixedArray not needed anymore).

R=mvstanton@chromium.org
==========

to

==========
Introduce {ConstantElementsPair} struct for type safety.

This introduces an explicit struct for the communication channel between
the {ArrayLiteral} AST node and the corresponding runtime methods. Those
methods take a pair of {ElementsKind} as well as an array (can either be
a FixedArray or a FixedDoubleArray) of constant values.

For bonus points it also reduces the size of the involved heap object by
one word (i.e. length field of FixedArray not needed anymore).

R=mvstanton@chromium.org

Review-Url: https://codereview.chromium.org/2581683003
Cr-Commit-Position: refs/heads/master@{#41752}
Committed:
https://chromium.googlesource.com/v8/v8/+/92b370ee642743d4d795536900da7715c73...
==========

[commit-bot: I haz the power, 2016-12-16 10:57:15]

Committed patchset #5 (id:70001) as
https://chromium.googlesource.com/v8/v8/+/92b370ee642743d4d795536900da7715c73...